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Sample records for acid mixture polyamine

  1. 40 CFR 721.6220 - Aryl sulfonate of a fatty acid mixture, polyamine condensate.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Aryl sulfonate of a fatty acid mixture... Specific Chemical Substances § 721.6220 Aryl sulfonate of a fatty acid mixture, polyamine condensate. (a... generically as an aryl sulfonate of a fatty acid mixture, polyamine condensate (PMN P-91-584) is subject...

  2. 40 CFR 721.6220 - Aryl sulfonate of a fatty acid mixture, polyamine condensate.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Aryl sulfonate of a fatty acid mixture... Specific Chemical Substances § 721.6220 Aryl sulfonate of a fatty acid mixture, polyamine condensate. (a... generically as an aryl sulfonate of a fatty acid mixture, polyamine condensate (PMN P-91-584) is subject...

  3. 40 CFR 721.6220 - Aryl sulfonate of a fatty acid mixture, polyamine condensate.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Aryl sulfonate of a fatty acid mixture... Specific Chemical Substances § 721.6220 Aryl sulfonate of a fatty acid mixture, polyamine condensate. (a... generically as an aryl sulfonate of a fatty acid mixture, polyamine condensate (PMN P-91-584) is subject...

  4. 40 CFR 721.6220 - Aryl sulfonate of a fatty acid mixture, polyamine condensate.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Aryl sulfonate of a fatty acid mixture... Specific Chemical Substances § 721.6220 Aryl sulfonate of a fatty acid mixture, polyamine condensate. (a... generically as an aryl sulfonate of a fatty acid mixture, polyamine condensate (PMN P-91-584) is subject...

  5. 40 CFR 721.6220 - Aryl sulfonate of a fatty acid mixture, polyamine condensate.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Aryl sulfonate of a fatty acid mixture... Specific Chemical Substances § 721.6220 Aryl sulfonate of a fatty acid mixture, polyamine condensate. (a... generically as an aryl sulfonate of a fatty acid mixture, polyamine condensate (PMN P-91-584) is subject...

  6. Polyamines are Inhibitors of Gastric Acid Secretion

    NASA Astrophysics Data System (ADS)

    Ray, Tushar K.; Nandi, Jyotirmoy; Pidhorodeckyj, Nykolai; Meng-Ai, Zhou

    1982-03-01

    The naturally occurring organic polycations such as spermine and spermidine inhibit histamine-stimulated gastric acid secretion by bullfrog gastric mucosa in vitro; spermine is much more potent than spermidine. Unlike the H2 receptor antagonists, the polyamines are completely ineffective from the nutrient side and are effective only from the secretory side of the chambered mucosa. The polyamine effects could be reversed by increasing K+ concentration in the secretory solution. Studies with isolated gastric microsomal vesicles demonstrate that the polyamines do not inhibit the gastric H+,K+-ATPase but greatly decrease the ATPase-mediated uptake of H+ under appropriate conditions. For the latter effects the presence of polyamine within the vesicle interior was found to be essential. Our data strongly suggest an uncoupling of the gastric H+,K+-ATPase system by the polyamines. The therapeutic potential of these and similar compounds in the treatment of hyperacidity and peptic ulcer is discussed.

  7. Analysis of aromatic polyamine mixtures for formulation of LARC-160 resin

    NASA Technical Reports Server (NTRS)

    Young, P. R.; Sykes, G. F.

    1980-01-01

    An investigation was conducted to identify a potential substitute for the aromatic polyamine mixture, Jeffamine AP-22, currently used to formulate LARC-160 polyimide precursor resin. Jeffamine AP-22 was characterized by high pressure liquid chromatography and mass spectrometry. Eleven different aromatic amines in the mixture were isolated and identified. Subsequent liquid chromatographic analysis of nine additional commercially available aromatic polyamine mixtures identified three candidates that are similar in composition to AP-22.

  8. Polyamines

    NASA Astrophysics Data System (ADS)

    Marton, Laurence J.

    The polyamines spermidine [NH2(CH2)3NH(CH2)4NH2] and spermine [NH2(CH2)3NH(CH2)4NH(CH2)3NH2] and their diamine precursor, putrescine [NH2(CH2)4NH2], have been the subject of intense study relative to their potential as tumor markers during the past decade (1). These compounds have been implicated in numerous biochemical reactions and have been clearly associated with cellular growth processes. A number of publications have reviewed our present knowledge regarding these compounds, including their relationship to human disease (2-6).

  9. 40 CFR 721.6200 - Fatty acid polyamine condensate, phosphoric acid ester salts.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ..., phosphoric acid ester salts. 721.6200 Section 721.6200 Protection of Environment ENVIRONMENTAL PROTECTION... ester salts. (a) Chemical substances and significant new uses subject to reporting. (1) The chemical substances identified as fatty acid polyamine condensate, phosphate ester salts (PMNs P-90-1984 and...

  10. 40 CFR 721.6200 - Fatty acid polyamine condensate, phosphoric acid ester salts.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ..., phosphoric acid ester salts. 721.6200 Section 721.6200 Protection of Environment ENVIRONMENTAL PROTECTION... ester salts. (a) Chemical substances and significant new uses subject to reporting. (1) The chemical substances identified as fatty acid polyamine condensate, phosphate ester salts (PMNs P-90-1984 and...

  11. 40 CFR 721.6200 - Fatty acid polyamine condensate, phosphoric acid ester salts.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ..., phosphoric acid ester salts. 721.6200 Section 721.6200 Protection of Environment ENVIRONMENTAL PROTECTION... ester salts. (a) Chemical substances and significant new uses subject to reporting. (1) The chemical substances identified as fatty acid polyamine condensate, phosphate ester salts (PMNs P-90-1984 and...

  12. 40 CFR 721.6200 - Fatty acid polyamine condensate, phosphoric acid ester salts.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ..., phosphoric acid ester salts. 721.6200 Section 721.6200 Protection of Environment ENVIRONMENTAL PROTECTION... ester salts. (a) Chemical substances and significant new uses subject to reporting. (1) The chemical substances identified as fatty acid polyamine condensate, phosphate ester salts (PMNs P-90-1984 and...

  13. 40 CFR 721.6200 - Fatty acid polyamine condensate, phosphoric acid ester salts.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ..., phosphoric acid ester salts. 721.6200 Section 721.6200 Protection of Environment ENVIRONMENTAL PROTECTION... ester salts. (a) Chemical substances and significant new uses subject to reporting. (1) The chemical substances identified as fatty acid polyamine condensate, phosphate ester salts (PMNs P-90-1984 and...

  14. Fuel and lubricant additives from acid treated mixtures of vegetable oil derived amides and esters

    SciTech Connect

    Bonazza, B.R.; Devault, A.N.

    1981-05-26

    Vegetable oils such as corn oil, peanut oil, and soy oil are reacted with polyamines to form a mixture containing amides, imides, half esters, and glycerol with subsequent treatment with a strong acid such as sulfonic acid to produce a product mix that has good detergent properties in fuels and lubricants.

  15. 40 CFR 721.10188 - Fatty acids, tall-oil, reaction products with 4-methyl-2-pentanone and aliphatic polyamine...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Fatty acids, tall-oil, reaction... Fatty acids, tall-oil, reaction products with 4-methyl-2-pentanone and aliphatic polyamine (generic). (a... generically as fatty acids, tall-oil, reaction products with 4-methyl-2-pentanone and aliphatic polyamine...

  16. 40 CFR 721.10188 - Fatty acids, tall-oil, reaction products with 4-methyl-2-pentanone and aliphatic polyamine...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Fatty acids, tall-oil, reaction... Fatty acids, tall-oil, reaction products with 4-methyl-2-pentanone and aliphatic polyamine (generic). (a... generically as fatty acids, tall-oil, reaction products with 4-methyl-2-pentanone and aliphatic polyamine...

  17. 40 CFR 721.10188 - Fatty acids, tall-oil, reaction products with 4-methyl-2-pentanone and aliphatic polyamine...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Fatty acids, tall-oil, reaction... Fatty acids, tall-oil, reaction products with 4-methyl-2-pentanone and aliphatic polyamine (generic). (a... generically as fatty acids, tall-oil, reaction products with 4-methyl-2-pentanone and aliphatic polyamine...

  18. 40 CFR 721.10188 - Fatty acids, tall-oil, reaction products with 4-methyl-2-pentanone and aliphatic polyamine...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Fatty acids, tall-oil, reaction... Fatty acids, tall-oil, reaction products with 4-methyl-2-pentanone and aliphatic polyamine (generic). (a... generically as fatty acids, tall-oil, reaction products with 4-methyl-2-pentanone and aliphatic polyamine...

  19. 40 CFR 721.10188 - Fatty acids, tall-oil, reaction products with 4-methyl-2-pentanone and aliphatic polyamine...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Fatty acids, tall-oil, reaction... Fatty acids, tall-oil, reaction products with 4-methyl-2-pentanone and aliphatic polyamine (generic). (a... generically as fatty acids, tall-oil, reaction products with 4-methyl-2-pentanone and aliphatic polyamine...

  20. Polyamines are essential for the synthesis of 2-ricinoleoyl phosphatidic acid in developing seeds of castor.

    PubMed

    Tomosugi, Mitsuhiro; Ichihara, Ken'ichi; Saito, Kazumi

    2006-01-01

    The major fatty acid component of castor (Ricinus communis L.) oil is ricinoleic acid (12-hydroxy-cis-9-octadecenoic acid), and unsaturated hydroxy acid accounts for >85% of the total fatty acids in triacylglycerol (TAG). TAG had a higher ricinoleate content at position 2 than at positions 1 and 3. Although lysophosphatidic acid (LPA) acyltransferase (EC 2.3.1.51), which catalyzes acylation of LPA at position 2, was expected to utilize ricinoleoyl-CoA preferentially over other fatty acyl-CoAs, no activity was found for ricinoleoyl-CoA in vitro at concentrations at which other unsaturated acyl-CoAs were incorporated rapidly. However, activity for ricinoleoyl-CoA appeared with addition of polyamines (putrescine, spermidine, and spermine), while polyamines decreased the rates of incorporation of other acyl-CoAs into position 2. The order of effect of polyamines on LPA acyltransferase activity was spermine > spermidine > putrescine. At concentrations of spermine and spermidine of >0.1 mM, ricinoleoyl-CoA served as an effective substrate for LPA acyltransferase reaction. The concentrations of spermine and spermidine in the developing seeds were estimated at approximately 0.09 and approximately 0.63 mM, respectively. These stimulatory effects for incorporation of ricinoleate were specific to polyamines, but basic amino acids were ineffective as cations. In contrast, in microsomes from safflower seeds that do not contain ricinoleic acid, spermine and spermidine stimulated the LPA acyltransferase reaction for all acyl-CoAs tested, including ricinoleoyl-CoA. Although the fatty acid composition of TAG depends on both acyl-CoA composition in the cell and substrate specificity of acyltransferases, castor bean polyamines are crucial for incorporation of ricinoleate into position 2 of LPA. Polyamines are essential for synthesis of 2-ricinoleoyl phosphatidic acid in developing castor seeds.

  1. Nanoparticle strategies for cancer therapeutics: Nucleic acids, polyamines, bovine serum amine oxidase and iron oxide nanoparticles (Review).

    PubMed

    Agostinelli, Enzo; Vianello, Fabio; Magliulo, Giuseppe; Thomas, Thresia; Thomas, T J

    2015-01-01

    Nanotechnology for cancer gene therapy is an emerging field. Nucleic acids, polyamine analogues and cytotoxic products of polyamine oxidation, generated in situ by an enzyme-catalyzed reaction, can be developed for nanotechnology-based cancer therapeutics with reduced systemic toxicity and improved therapeutic efficacy. Nucleic acid-based gene therapy approaches depend on the compaction of DNA/RNA to nanoparticles and polyamine analogues are excellent agents for the condensation of nucleic acids to nanoparticles. Polyamines and amine oxidases are found in higher levels in tumours compared to that of normal tissues. Therefore, the metabolism of polyamines spermidine and spermine, and their diamine precursor, putrescine, can be targets for antineoplastic therapy since these naturally occurring alkylamines are essential for normal mammalian cell growth. Intracellular polyamine concentrations are maintained at a cell type-specific set point through the coordinated and highly regulated interplay between biosynthesis, transport, and catabolism. In particular, polyamine catabolism involves copper-containing amine oxidases. Several studies showed an important role of these enzymes in developmental and disease-related processes in animals through the control of polyamine homeostasis in response to normal cellular signals, drug treatment, and environmental and/or cellular stress. The production of toxic aldehydes and reactive oxygen species (ROS), H2O2 in particular, by these oxidases suggests a mechanism by which amine oxidases can be exploited as antineoplastic drug targets. The combination of bovine serum amine oxidase (BSAO) and polyamines prevents tumour growth, particularly well if the enzyme has been conjugated with a biocompatible hydrogel polymer. The findings described herein suggest that enzymatically formed cytotoxic agents activate stress signal transduction pathways, leading to apoptotic cell death. Consequently, superparamagnetic nanoparticles or other

  2. Abscisic acid signals reorientation of polyamine metabolism to orchestrate stress responses via the polyamine exodus pathway in grapevine.

    PubMed

    Toumi, Imene; Moschou, Panagiotis N; Paschalidis, Konstantinos A; Bouamama, Badra; Ben Salem-Fnayou, Asma; Ghorbel, Abdel Wahed; Mliki, Ahmed; Roubelakis-Angelakis, Kalliopi A

    2010-05-01

    Polyamines (PAs) have been suggested to be implicated in plant responses to abiotic and biotic stress. Grapevine is a model perennial plant species whose cultivars respond differently to osmotic stress. In this study, we used two cultivars, one sensitive (S) and one tolerant (T) to drought. In adult vines subjected to drought under greenhouse conditions, total PAs were significantly lower in the control T- and higher in the control S-genotype and significantly increased or decreased, respectively, post-treatment. Soluble Put and Spd exhibited the greatest increase on d 8 post-treatment in the T- but not in the S-genotype, which accumulated soluble Spm. Abscisic acid (ABA) was differentially accumulated in T- and S-genotypes under drought conditions, and activated the PA biosynthetic pathway, which in turn was correlated with the differential increases in PA titers. In parallel, polyamine oxidases (PAOs) increased primarily in the S-genotype. ABA at least partially induced PA accumulation and exodus into the apoplast, where they were oxidized by the apoplastic amine oxidases (AOs), producing H2O2, which signaled secondary stress responses. The results here show that the ABA signaling pathway integrates PAs and AOs to regulate the generation of H2O2, which signals further stress responses or the PCD syndrome.

  3. Trypanocidal Effect of Isotretinoin through the Inhibition of Polyamine and Amino Acid Transporters in Trypanosoma cruzi.

    PubMed

    Reigada, Chantal; Valera-Vera, Edward A; Sayé, Melisa; Errasti, Andrea E; Avila, Carla C; Miranda, Mariana R; Pereira, Claudio A

    2017-03-01

    Polyamines are essential compounds to all living organisms and in the specific case of Trypanosoma cruzi, the causative agent of Chagas disease, they are exclusively obtained through transport processes since this parasite is auxotrophic for polyamines. Previous works reported that retinol acetate inhibits Leishmania growth and decreases its intracellular polyamine concentration. The present work describes a combined strategy of drug repositioning by virtual screening followed by in vitro assays to find drugs able to inhibit TcPAT12, the only polyamine transporter described in T. cruzi. After a screening of 3000 FDA-approved drugs, 7 retinoids with medical use were retrieved and used for molecular docking assays with TcPAT12. From the docked molecules, isotretinoin, a well-known drug used for acne treatment, showed the best interaction score with TcPAT12 and was selected for further in vitro studies. Isotretinoin inhibited the polyamine transport, as well as other amino acid transporters from the same protein family (TcAAAP), with calculated IC50 values in the range of 4.6-10.3 μM. It also showed a strong inhibition of trypomastigote burst from infected cells, with calculated IC50 of 130 nM (SI = 920) being significantly less effective on the epimastigote stage (IC50 = 30.6 μM). The effect of isotretinoin on the parasites plasma membrane permeability and on mammalian cell viability was tested, and no change was observed. Autophagosomes and apoptotic bodies were detected as part of the mechanisms of isotretinoin-induced death indicating that the inhibition of transporters by isotretinoin causes nutrient starvation that triggers autophagic and apoptotic processes. In conclusion, isotretinoin is a promising trypanocidal drug since it is a multi-target inhibitor of essential metabolites transporters, in addition to being an FDA-approved drug largely used in humans, which could reduce significantly the requirements for its possible application in the treatment of

  4. Trypanocidal Effect of Isotretinoin through the Inhibition of Polyamine and Amino Acid Transporters in Trypanosoma cruzi

    PubMed Central

    Reigada, Chantal; Valera-Vera, Edward A.; Sayé, Melisa; Errasti, Andrea E.; Avila, Carla C.; Miranda, Mariana R.; Pereira, Claudio A.

    2017-01-01

    Polyamines are essential compounds to all living organisms and in the specific case of Trypanosoma cruzi, the causative agent of Chagas disease, they are exclusively obtained through transport processes since this parasite is auxotrophic for polyamines. Previous works reported that retinol acetate inhibits Leishmania growth and decreases its intracellular polyamine concentration. The present work describes a combined strategy of drug repositioning by virtual screening followed by in vitro assays to find drugs able to inhibit TcPAT12, the only polyamine transporter described in T. cruzi. After a screening of 3000 FDA-approved drugs, 7 retinoids with medical use were retrieved and used for molecular docking assays with TcPAT12. From the docked molecules, isotretinoin, a well-known drug used for acne treatment, showed the best interaction score with TcPAT12 and was selected for further in vitro studies. Isotretinoin inhibited the polyamine transport, as well as other amino acid transporters from the same protein family (TcAAAP), with calculated IC50 values in the range of 4.6–10.3 μM. It also showed a strong inhibition of trypomastigote burst from infected cells, with calculated IC50 of 130 nM (SI = 920) being significantly less effective on the epimastigote stage (IC50 = 30.6 μM). The effect of isotretinoin on the parasites plasma membrane permeability and on mammalian cell viability was tested, and no change was observed. Autophagosomes and apoptotic bodies were detected as part of the mechanisms of isotretinoin-induced death indicating that the inhibition of transporters by isotretinoin causes nutrient starvation that triggers autophagic and apoptotic processes. In conclusion, isotretinoin is a promising trypanocidal drug since it is a multi-target inhibitor of essential metabolites transporters, in addition to being an FDA-approved drug largely used in humans, which could reduce significantly the requirements for its possible application in the treatment of

  5. Age dependency of the metabolic conversion of polyamines into amino acids in IMR-90 human embryonic lung diploid fibroblasts

    SciTech Connect

    Chen, K.Y.; Chang, Z.

    1986-07-01

    When radioactive polyamines (putrescine or spermidine) were incubated with mammalian cells in tissue culture, the radioactivity was incorporated into cellular proteins via two different metabolic pathways; one is metabolic labeling of an 18,000-dalton protein via hypusine formation, and the other is general protein synthesis employing radioactive amino acids derived from biodegradation of polyamines via GABA shunt and Krebs cycle. Aminoguanidine, a potent inhibitor of diamine oxidase, blocked the metabolic conversion of polyamines to amino acids but had no effect on the metabolic labeling of the 18,000-dalton protein. The authors have investigated these two polyamine-associated biochemical events in IMR-90 human diploid fibroblasts as a function of their population doubling level (PDL). They found that (1) the metabolic labeling of the 18,000-dalton protein was about two-fold greater in young cells (PDL = 22) than that in old cells (PDL = 48), and (2) the metabolic labeling of other cellular proteins, employing amino acids derived from putrescine via polyamine catabolic pathway, was more than six-fold greater in the old cells (PDL = 48) than in the young cells (PDL = 22). Since the rate of protein synthesis was about 1.4-fold higher in the young cells as compared to the old cells, their data indicated that the activity of catabolic conversion of putrescine (or spermidine) to amino acids in old IMR-90 cells was about eight-fold greater than that in young cells. This remarkable increase of polyamine catabolism and the slight decrease of metabolic labeling of the 18,000-dalton protein were also observed in cell strains derived from patients with premature aging disease.

  6. Polyamine homoeostasis.

    PubMed

    Persson, Lo

    2009-11-04

    The polyamines are essential for a variety of functions in the mammalian cell. Although their specific effects have not been fully elucidated, it is clear that the cellular polyamines have to be kept within certain levels for normal cell function. Polyamine homoeostasis in mammalian cells is achieved by a complex network of regulatory mechanisms affecting synthesis and degradation, as well as membrane transport of polyamines. The two key enzymes in the polyamine biosynthetic pathway, ODC (ornithine decarboxylase) and AdoMetDC (S-adenosylmethionine decarboxylase), are strongly regulated by feedback mechanisms at several levels, including transcriptional, translational and post-translational. Some of these mechanisms have been shown to be truly unique and include upstream reading frames and ribosomal frameshifting, as well as ubiquitin-independent proteasomal degradation. SSAT (spermidine/spermine N1-acetyltransferase), which is a crucial enzyme for degradation and efflux of polyamines, is also highly regulated by polyamines. A cellular excess of polyamines rapidly induces SSAT, resulting in increased degradation/efflux of the polyamines. The polyamines appear to induce both transcription and translation of the SSAT mRNA. However, the major part of the polyamine-induced increase in SSAT is caused by a marked stabilization of the enzyme against degradation by the 26S proteasome. In addition, active transport of extracellular polyamines into the cell contributes to cellular polyamine homoeostasis. Depletion of cellular polyamines rapidly induces an increased uptake of exogenous polyamines, whereas an excess of polyamines down-regulates the polyamine transporter(s). However, the protein(s) involved in polyamine transport and the exact mechanisms by which the polyamines regulate the transporter(s) are not yet known.

  7. Isolation, Amino Acid Sequence and Biological Activities of Novel Long-Chain Polyamine-Associated Peptide Toxins from the Sponge Axinyssa aculeata

    PubMed Central

    Matsunaga, Satoko; Jimbo, Mitsuru; Gill, Martin B.; Lash-Van Wyhe, L. Leanne; Murata, Michio; Nonomura, Ken’ichi; Swanson, Geoffrey T.

    2012-01-01

    A novel family of functionalized peptide toxins, aculeines (ACUs), was isolated from the marine sponge Axinyssa aculeate. ACUs are polypeptides with N-terminal residues that are modified by the addition of long-chain polyamines (LCPA). Aculeines were present in the sponge extract as a complex mixture with differing polyamine chain lengths and peptide structures. ACU-A and B, which were purified in this study, share a common polypeptide chain but differ in their N-terminal residue modifications. The amino acid sequence of the polypeptide portion of ACU-A and B was deduced from 3′ and 5′ RACE, and supported by Edman degradation and mass spectral analysis of peptide fragments. ACU induced convulsions upon intracerebroventricular (i.c.v.) injection in mice, and disrupted neuronal membrane integrity in electrophysiological assays. ACU also lysed erythrocytes with a potency that differed between animal species. Here we describe the isolation, amino acid sequence, and biological activity of this new group of cytotoxic sponge peptides. PMID:21830292

  8. EFFECT OF POLYAMINE STRUCTURE ON GROWTH STIMULATION AND SPERMINE AND SPERMIDINE CONTENT OF LACTIC ACID BACTERIA

    PubMed Central

    Guirard, Beverly M.; Snell, Esmond E.

    1964-01-01

    Guirard, Beverly M. (University of California, Berkeley), and Esmond E. Snell. Effect of polyamine structure on growth and spermine and spermidine content of lactic acid bacteria. J. Bacteriol. 88:72–80. 1964.—Growth from small inocula of six species of lactobacilli was stimulated by addition of spermine or spermidine to a defined medium; none of four streptococcal species showed this effect. Lactobacillus casei was stimulated to the greatest extent. Several homologues and analogues partially duplicated the growth-promoting effects of spermidine; one inactive homologue, N-(3-aminopropyl)-1,6-hexanediamine, competitively inhibited the growth response to spermidine and spermine, and reduced or eliminated the response to several weakly active compounds. A procedure for separation of spermine and spermidine, and their estimation by bioassay with L. casei, was developed and applied to the estimation of these compounds in bacterial cells. Both compounds are present in lactic acid bacteria in amounts much smaller (1 to 5%) than those found in Escherichia coli. Addition of spermine or spermidine to the growth medium results in large accumulations in the cells, and the two amines show limited interconvertibility. Putrescine does not increase the cell content of either spermine or spermidine. Presence of the inhibitor prevents accumulation of the growth-stimulating amines. The polyamines appear to fill at least two valuable roles in the cell, one relatively nonspecific in its structural requirements, and one filled only by spermine and spermidine or their nearest homologues. N-(3-aminopropyl)-1,6-hexanediamine appears to prevent the latter function by competition for an appropriate cellular receptor. PMID:14197908

  9. Salicylic acid differently impacts ethylene and polyamine synthesis in the glycophyte Solanum lycopersicum and the wild-related halophyte Solanum chilense exposed to mild salt stress.

    PubMed

    Gharbi, Emna; Martínez, Juan-Pablo; Benahmed, Hela; Fauconnier, Marie-Laure; Lutts, Stanley; Quinet, Muriel

    2016-10-01

    This study aimed to determine the effects of exogenous application of salicylic acid (SA) on the toxic effects of salt in relation to ethylene and polyamine synthesis, and to correlate these traits with the expression of genes involved in ethylene and polyamine metabolism in two tomato species differing in their sensitivity to salt stress, Solanum lycopersicum cv Ailsa Craig and its wild salt-resistant relative Solanum chilense. In S. chilense, treatment with 125 mM NaCl improved plant growth, increased production of ethylene, endogenous salicylic acid and spermine. The production was related to a modification of expression of genes involved in ethylene and polyamine metabolism. In contrast, salinity decreased plant growth in S. lycopersicum without affecting endogenous ethylene, salicylic or polyamine concentrations. Exogenous application of salicylic acid at 0.01 mM enhanced shoot growth in both species and affected ethylene and polyamine production in S. chilense. Concomitant application of NaCl and salicylic acid improved osmotic adjustment, thus suggesting that salt and SA may act in synergy on osmolyte synthesis. However, the beneficial impact of exogenous application of salicylic acid was mitigated by salt stress since NaCl impaired endogenous SA accumulation in the shoot and salicylic acid did not improve plant growth in salt-treated plants. Our results thus revealed that both species respond differently to salinity and that salicylic acid, ethylene and polyamine metabolisms are involved in salt resistance in S. chilense.

  10. Accumulation of wound-inducible ACC synthase transcript in tomato fruit is inhibited by salicylic acid and polyamines.

    PubMed

    Li, N; Parsons, B L; Liu, D R; Mattoo, A K

    1992-02-01

    Regulation of wound-inducible 1-aminocyclopropane-1-carboxylic acid (ACC) synthase expression was studied in tomato fruit (Lycopersicon esculentum cv. Pik-Red). A 70 base oligonucleotide probe homologous to published ACC synthase cDNA sequences was successfully used to identify and analyze regulation of a wound-inducible transcript. The 1.8 kb ACC synthase transcript increased upon wounding the fruit as well as during fruit ripening. Salicylic acid, an inhibitor of wound-responsive genes in tomato, inhibited the wound-induced accumulation of the ACC synthase transcript. Further, polyamines (putrescine, spermidine and spermine) that have anti-senescence properties and have been shown to inhibit the development of ACC synthase activity, inhibited the accumulation of the wound-inducible ACC synthase transcript. The inhibition by spermine was greater than that caused by putrescine or spermidine. The transcript level of a wound-repressible glycine-rich protein gene and that of the constitutively expressed rRNA were not affected as markedly by either salicylic acid or polyamines. These data suggest that salicylic acid and polyamines may specifically regulate ethylene biosynthesis at the level of ACC synthase transcript accumulation.

  11. Effect of salicylic acid treatment on postharvest quality, antioxidant activities, and free polyamines of asparagus.

    PubMed

    Wei, Yunxiao; Liu, Zhenfeng; Su, Yujing; Liu, Donghong; Ye, Xingqian

    2011-03-01

    The effects of salicylic acid (SA) on the quality and antioxidant activity of asparagus stored at 18 ± 2 °C were investigated by analyzing the color, chlorophyll, shear force, and the activity of antioxidant compounds such as ascorbic acid, phenolics, flavonoids, 1,1-Diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity ferric reducing antioxidant power (FRAP), and polyamines (PAs). The results showed that SA improved the color and maintained the chlorophyll, phenolic, flavonoid, and ascorbic acid content of asparagus. High concentrations of SA caused a deterioration in asparagus would harm to color and had no effect on shear force within 6 d. SA induced the maximum concentration of phenolics in postharvest asparagus, promoted the increase in total flavonoids before 6 to 9 d, affected the antioxidant activity positively as indicated by the resultant increase in FRAP concentration; however, SA was only active with regard to DPPH scavenging activity within 6 d of treatment. Spermidine (Spd) is the most common form of PA in asparagus, and free putrescine (Put) contents increased over the first 3 d following harvest and then decreased. Spd and Spm concentrations evolved in a similar way and decreased during storage. Higher Spd and Spm contents in the SA pre-treatment Put was inhabited and its peaks appeared later.

  12. Polyamine/salt-assembled microspheres coated with hyaluronic acid for targeting and pH sensing.

    PubMed

    Zhang, Pan; Yang, Hui; Wang, Guojun; Tong, Weijun; Gao, Changyou

    2016-06-01

    The poly(allylamine hydrochloride)/trisodium citrate aggregates were fabricated and further covalently crosslinked via the coupling reaction of carboxylic sites on trisodium citrate with the amine groups on polyamine, onto which poly-L-lysine and hyaluronic acid were sequentially assembled, forming stable microspheres. The pH sensitive dye and pH insensitive dye were further labeled to enable the microspheres with pH sensing property. Moreover, these microspheres could be specifically targeted to HeLa tumor cells, since hyaluronic acid can specifically recognize and bind to CD44, a receptor overexpressed on many tumor cells. Quantitative pH measurement by confocal laser scanning microscopy demonstrated that the microspheres were internalized into HeLa cells, and accumulated in acidic compartments. By contrast, only a few microspheres were adhered on the NIH 3T3 cells surface. The microspheres with combined pH sensing property and targeting ability can enhance the insight understanding of the targeted drug vehicles trafficking after cellular internalization.

  13. GABA shunt and polyamine degradation pathway on γ-aminobutyric acid accumulation in germinating fava bean (Vicia faba L.) under hypoxia.

    PubMed

    Yang, Runqiang; Guo, Qianghui; Gu, Zhenxin

    2013-01-01

    GABA shunt and polyamine degradation pathway on γ-aminobutyric acid (GABA) accumulation in germinating fava bean under hypoxia was investigated. GABA content, GAD and DAO activity were significantly increased under hypoxia treatment. Glu and polyamine contents enhanced largely and thus supplied as sufficient substrates for GABA formation. In contrast, GABA content decreased, mainly in the embryo, after removing the hypoxia stress. DAO activity, Glu and polyamines contents decreased, while an increment of GAD activity was observed. This indicated that GAD activity can be not only regulated by hypoxia, but by the rapid growth of embryo after the recovery from hypoxia stress. When treated with AG, DAO activity was almost inhibited completely, and the GABA content decreased by 32.96% and 32.07% after treated for 3 and 5 days, respectively. Hence, it can be inferred that about 30% of GABA formed in germinating fava bean under hypoxia was supplied by polyamine degradation pathway.

  14. Polyamine sensitization in offshore workers handling drilling muds.

    PubMed

    Ormerod, A D; Wakeel, R A; Mann, T A; Main, R A; Aldridge, R D

    1989-11-01

    Oil-based mud, a complex mixture containing amines in emulsifiers, is used in offshore drilling operations. It is a skin irritant that occasionally gives rise to allergic contact sensitivity. In patch testing patients with allergy to drilling mud, we have identified polyamine (diethylenetriamine and triethylenetetramine) sensitivity in 5 patients. All 5 patients were also allergic to emulsifiers. These emulsifiers are cross-linked fatty acid amido-amines, in which unreacted amine groups are thought to cross-sensitize with these constituent polyamines. Cross-reactivity between ethylenediamine, diethylenetetramine and triethylenetetramine was found in 9 subjects.

  15. Polyamine-oligonucleotide conjugates: a promising direction for nucleic acid tools and therapeutics.

    PubMed

    Menzi, Mirjam; Lightfoot, Helen L; Hall, Jonathan

    2015-01-01

    Chemical modification and/or the conjugation of small functional molecules to oligonucleotides have significantly improved their biological and biophysical properties, addressing issues such as poor cell penetration, stability to nucleases and low affinity for their targets. Here, the authors review the literature reporting on the biophysical, biochemical and biological properties of one particular class of modification - polyamine-oligonucleotide conjugates. Naturally derived and synthetic polyamines have been grafted onto a variety of oligonucleotide formats, including antisense oligonucleotides and siRNAs. In many cases this has had beneficial effects on their properties such as target hybridization, nuclease resistance, cellular uptake and activity. Polyamine-oligonucleotide conjugation, therefore, represents a promising direction for the further development of oligonucleotide-based therapeutics and tools.

  16. Polyamines in plant physiology

    NASA Technical Reports Server (NTRS)

    Galston, A. W.; Sawhney, R. K.

    1990-01-01

    The diamine putrescine, the triamine spermidine, and the tetramine spermine are ubiquitous in plant cells, while other polyamines are of more limited occurrence. Their chemistry and pathways of biosynthesis and metabolism are well characterized. They occur in the free form as cations, but are often conjugated to small molecules like phenolic acids and also to various macromolecules. Their titer varies from approximately micromolar to more than millimolar, and depends greatly on environmental conditions, especially stress. In cereals, the activity of one of the major polyamine biosynthetic enzymes, arginine decarboxylase, is rapidly and dramatically increased by almost every studied external stress, leading to 50-fold or greater increases in putrescine titer within a few hours. The physiological significance of this increase is not yet clear, although most recent work suggests an adaptive, protective role. Polyamines produced through the action of ornithine decarboxylase, by contrast, seem essential for DNA replication and cell division. The application of exogenous polyamines produces effects on patterns of senescence and morphogenesis, suggesting but not proving a regulatory role for polyamines in these processes. The evidence for such a regulatory role is growing.

  17. Ornithine decarboxylase, polyamines and CD11b expression in HL-60 cells during differentiation induced by retinoic acid.

    PubMed

    Stabellini, Giordano; Brugnoli, F; Calastrini, C; Vizzotto, L; Vertemati, M; Baroni, T; Caramelli, E; Marinucci, L; Pellati, A; Bertagnolo, V

    2004-01-01

    Polyamines (PA) and retinoic acid affect mammalian cell growth, differentiation and apoptosis. Retinoic acid induces granulocytic differentiation of mieloid cell lines and, during this process, is responsible for the expression of CD11b, a surface antigen. In this study we investigate the effects of retinoic acid on HL-60 cells, monitoring ornithine decarboxylase (ODC) activity (enzyme rate of PA), putrescine (PUT), spermidine (SPD), spermine (SPM) levels, CD11b myeloid surface marker differentiation, cell cycle, and apoptosis. ODC activity and PUT levels are correlated with mieloid cell differentiation induced by retinoic acid treatment. Only the ODC/PUT ratio is connected with retinoic acid treated HL-60 cells. Treated cultures show a decrease of proliferation and a cell block in the G0/G1 phase, with consequent diminished S phase. The G0/G1 and S phases are significantly related to ODC activity and to PUT and SPD behavior, whereas in differentiating condition only the decrease of PUT is related to the S phase. CD11b expression, stimulated by retinoic acid treatment, is associated with the SPM trend. Total PA behavior agrees with apoptotic cell increase after 96 h of stimulation. Our data show that retinoic acid treatment modifies ODC activity and the turnover of PA. PUT, SPD and SPM, therefore, have a different role, and may be involved in the differentiative/apoptotic program of retinoic acid treated HL-60 cells.

  18. Physicochemical properties of pH-controlled polyion complex (PIC) micelles of poly(acrylic acid)-based double hydrophilic block copolymers and various polyamines.

    PubMed

    Warnant, J; Marcotte, N; Reboul, J; Layrac, G; Aqil, A; Jerôme, C; Lerner, D A; Gérardin, C

    2012-05-01

    The physicochemical properties of polyion complex (PIC) micelles were investigated in order to characterize the cores constituted of electrostatic complexes of two oppositely charged polyelectrolytes. The pH-sensitive micelles were obtained with double hydrophilic block copolymers containing a poly(acrylic acid) block linked to a modified poly(ethylene oxide) block and various polyamines (polylysine, linear and branched polyethyleneimine, polyvinylpyridine, and polyallylamine). The pH range of micellization in which both components are ionized was determined for each polyamine. The resulting PIC micelles were characterized using dynamic light scattering and small-angle X-ray scattering experiments (SAXS). The PIC micelles presented a core-corona nanostructure with variable polymer density contrasts between the core and the corona, as revealed by the analysis of the SAXS curves. It was shown that PIC micelle cores constituted by polyacrylate chains and polyamines were more or less dense depending on the nature of the polyamine. It was also determined that the density of the cores of the PIC micelles depended strongly on the nature of the polyamine. These homogeneous cores were surrounded by a large hairy corona of hydrated polyethylene oxide block chains. Auramine O (AO) was successfully entrapped in the PIC micelles, and its fluorescence properties were used to get more insight on the core properties. Fluorescence data confirmed that the cores of such micelles are quite compact and that their microviscosity depended on the nature of the polyamine. The results obtained on these core-shell micelles allow contemplating a wide range of applications in which the AO probe would be replaced by various cationic drugs or other similarly charged species to form drug nanocarriers or new functional nanodevices.

  19. Improvement of plant abiotic stress tolerance through modulation of the polyamine pathway.

    PubMed

    Shi, Haitao; Chan, Zhulong

    2014-02-01

    Polyamines (mainly putrescine (Put), spermidine (Spd), and spermine (Spm)) have been widely found in a range of physiological processes and in almost all diverse environmental stresses. In various plant species, abiotic stresses modulated the accumulation of polyamines and related gene expression. Studies using loss-of-function mutants and transgenic overexpression plants modulating polyamine metabolic pathways confirmed protective roles of polyamines during plant abiotic stress responses, and indicated the possibility to improve plant tolerance through genetic manipulation of the polyamine pathway. Additionally, putative mechanisms of polyamines involved in plant abiotic stress tolerance were thoroughly discussed and crosstalks among polyamine, abscisic acid, and nitric oxide in plant responses to abiotic stress were emphasized. Special attention was paid to the interaction between polyamine and reactive oxygen species, ion channels, amino acid and carbon metabolism, and other adaptive responses. Further studies are needed to elucidate the polyamine signaling pathway, especially polyamine-regulated downstream targets and the connections between polyamines and other stress responsive molecules.

  20. Comparison of polyamine metabolism in tomato plants exposed to different concentrations of salicylic acid under light or dark conditions.

    PubMed

    Takács, Zoltán; Poór, Péter; Tari, Irma

    2016-11-01

    In this study the effect of exogenous 0.1 mM and 1 mM salicylic acid (SA) treatments were investigated on polyamine (PA) metabolism in tomato (Solanum lycopersicum L. cv. Ailsa Craig) leaves in illuminated or dark environments. The former proved to be sublethal and the latter lethal concentration for tomato leaf tissues. While PA biosynthetic genes, arginine- and ornitine decarboxylases or spermidine- and spermine synthases were highly up-regulated by 1 mM SA, the enzymes participating in PA catabolism, diamine- (DAOs, EC 1.4.3.6) and polyamine oxidases (PAOs, EC 1.5.3.3) displayed higher transcript abundance and enzyme activity at 0.1 mM SA. As a result, putrescine and spermine content but not that of spermidine increased after 1 mM SA application, which proved to be higher in the dark than in the light. H2O2 content produced on the effect of 1 mM SA was significantly higher than at 0.1 mM SA in the light. Since there was no coincidence between H2O2 accumulation and terminal PA catabolism, reactive oxygen species produced by photosynthesis and by other sources had more pronounced effect on H2O2 generation at tissue level than DAOs and PAOs. Accordingly, H2O2 in the absence of NO accumulation contributed to the initiation of defence reactions after 0.1 mM SA treatment, while high SA concentration generated simultaneous increase in H2O2 and NO production in the light, which induced cell death within 24 h in illuminated leaves. However, the appearance of necrotic lesions was delayed in the absence of NO if these plants were kept in darkness.

  1. Abscisic acid, H2O2 and nitric oxide interactions mediated cold-induced S-adenosylmethionine synthetase in Medicago sativa subsp. falcata that confers cold tolerance through up-regulating polyamine oxidation.

    PubMed

    Guo, Zhenfei; Tan, Jiali; Zhuo, Chunliu; Wang, Congying; Xiang, Bin; Wang, Zengyu

    2014-06-01

    S-adenosylmethionine synthetase (SAMS) is the key enzyme catalysing the formation of S-adenosylmethionine (SAM), a precursor of polyamines and ethylene. To investigate the potential role of SAMS in cold tolerance, we isolated MfSAMS1 from the cold-tolerant germplasm Medicago sativa subsp. falcata and analysed the association of SAM-derived polyamines with cold tolerance. The expression of MfSAMS1 in leaves was greatly induced by cold, abscisic acid (ABA), H2O2 and nitric oxide (NO). Our data revealed that ABA, H2O2 and NO interactions mediated the cold-induced MfSAMS1 expression and cold acclimation in falcata. SAM, putrescine, spermidine and spermine levels, ethylene production and polyamine oxidation were sequentially altered in response to cold, indicating that SAMS-derived SAM is preferentially used in polyamine synthesis and homeostasis during cold acclimation. Antioxidant enzyme activities were also induced in response to cold and showed correlation with polyamine oxidation. Overexpression of MfSAMS1 in tobacco resulted in elevated SAM levels, but polyamine levels and ethylene production in the transgenic plants were not significantly changed. Compared to the wild type, transgenic plants had increased levels of apoplastic H2O2, higher transcript levels of genes involved in polyamine synthesis and oxidation, and higher activities of polyamine oxidation and antioxidant enzymes. The results showed that overexpression of MfSAMS1 promoted polyamine synthesis and oxidation, which in turn improved H2 O2 -induced antioxidant protection, as a result enhanced tolerance to freezing and chilling stress in transgenic plants. This is the first report demonstrating that SAMS plays an important role in plant tolerance to cold via up-regulating polyamine oxidation.

  2. Polyamine analysis by LC-MS.

    PubMed

    Häkkinen, Merja R

    2011-01-01

    This chapter describes a protocol to analyze polyamines without any derivatization steps utilizing LC-MS/MS. Polyamines are separated by reversed phase LC prior MS analysis using heptafluorobutyric acid as MS compatible volatile ion-pairing agent, and selective and sensitive MS detection is performed using MS/MS in selected reaction monitoring mode.

  3. Polyamine analogues targeting epigenetic gene regulation.

    PubMed

    Huang, Yi; Marton, Laurence J; Woster, Patrick M; Casero, Robert A

    2009-11-04

    Over the past three decades the metabolism and functions of the polyamines have been actively pursued as targets for antineoplastic therapy. Interactions between cationic polyamines and negatively charged nucleic acids play a pivotal role in DNA stabilization and RNA processing that may affect gene expression, translation and protein activity. Our growing understanding of the unique roles that the polyamines play in chromatin regulation, and the discovery of novel proteins homologous with specific regulatory enzymes in polyamine metabolism, have led to our interest in exploring chromatin remodelling enzymes as potential therapeutic targets for specific polyamine analogues. One of our initial efforts focused on utilizing the strong affinity that the polyamines have for chromatin to create a backbone structure, which could be combined with active-site-directed inhibitor moieties of HDACs (histone deacetylases). Specific PAHAs (polyaminohydroxamic acids) and PABAs (polyaminobenzamides) polyamine analogues have demonstrated potent inhibition of the HDACs, re-expression of p21 and significant inhibition of tumour growth. A second means of targeting the chromatin-remodelling enzymes with polyamine analogues was facilitated by the recent identification of flavin-dependent LSD1 (lysine-specific demethylase 1). The existence of this enzyme demonstrated that histone lysine methylation is a dynamic process similar to other histone post-translational modifications. LSD1 specifically catalyses demethylation of mono- and di-methyl Lys4 of histone 3, key positive chromatin marks associated with transcriptional activation. Structural and catalytic similarities between LSD1 and polyamine oxidases facilitated the identification of biguanide, bisguanidine and oligoamine polyamine analogues that are potent inhibitors of LSD1. Cellular inhibition of LSD1 by these unique compounds led to the re-activation of multiple epigenetically silenced genes important in tumorigenesis. The use of

  4. Interaction of Polyamines, Abscisic Acid, Nitric Oxide, and Hydrogen Peroxide under Chilling Stress in Tomato (Lycopersicon esculentum Mill.) Seedlings

    PubMed Central

    Diao, Qiannan; Song, Yongjun; Shi, Dongmei; Qi, Hongyan

    2017-01-01

    Polyamines (PAs) play a vital role in the responses of higher plants to abiotic stresses. However, only a limited number of studies have examined the interplay between PAs and signal molecules. The aim of this study was to elucidate the cross-talk among PAs, abscisic acid (ABA), nitric oxide (NO), and hydrogen peroxide (H2O2) under chilling stress conditions using tomato seedlings [(Lycopersicon esculentum Mill.) cv. Moneymaker]. The study showed that during chilling stress (4°C; 0, 12, and 24 h), the application of spermidine (Spd) and spermine (Spm) elevated NO and H2O2 levels, enhanced nitrite reductase (NR), nitric oxide synthase (NOS)-like, and polyamine oxidase activities, and upregulated LeNR relative expression, but did not influence LeNOS1 expression. In contrast, putrescine (Put) treatment had no obvious impact. During the recovery period (25/15°C, 10 h), the above-mentioned parameters induced by the application of PAs were restored to their control levels. Seedlings pretreated with sodium nitroprusside (SNP, an NO donor) showed elevated Put and Spd levels throughout the treatment period, consistent with increased expression in leaves of genes encoding arginine decarboxylase (LeADC. LeADC1), ornithine decarboxylase (LeODC), and Spd synthase (LeSPDS) expressions in tomato leaves throughout the treatment period. Under chilling stress, the Put content increased first, followed by a rise in the Spd content. Exogenously applied SNP did not increase the expression of genes encoding S-adenosylmethionine decarboxylase (LeSAMDC) and Spm synthase (LeSPMS), consistent with the observation that Spm levels remained constant under chilling stress and during the recovery period. In contrast, exogenous Put significantly increased the ABA content and the 9-cis-epoxycarotenoid dioxygenase (LeNCED1) transcript level. Treatment with ABA could alleviate the electrolyte leakage (EL) induced by D-Arg (an inhibitor of Put). Taken together, it is concluded that, under chilling

  5. Interaction of Polyamines, Abscisic Acid, Nitric Oxide, and Hydrogen Peroxide under Chilling Stress in Tomato (Lycopersicon esculentum Mill.) Seedlings.

    PubMed

    Diao, Qiannan; Song, Yongjun; Shi, Dongmei; Qi, Hongyan

    2017-01-01

    Polyamines (PAs) play a vital role in the responses of higher plants to abiotic stresses. However, only a limited number of studies have examined the interplay between PAs and signal molecules. The aim of this study was to elucidate the cross-talk among PAs, abscisic acid (ABA), nitric oxide (NO), and hydrogen peroxide (H2O2) under chilling stress conditions using tomato seedlings [(Lycopersicon esculentum Mill.) cv. Moneymaker]. The study showed that during chilling stress (4°C; 0, 12, and 24 h), the application of spermidine (Spd) and spermine (Spm) elevated NO and H2O2 levels, enhanced nitrite reductase (NR), nitric oxide synthase (NOS)-like, and polyamine oxidase activities, and upregulated LeNR relative expression, but did not influence LeNOS1 expression. In contrast, putrescine (Put) treatment had no obvious impact. During the recovery period (25/15°C, 10 h), the above-mentioned parameters induced by the application of PAs were restored to their control levels. Seedlings pretreated with sodium nitroprusside (SNP, an NO donor) showed elevated Put and Spd levels throughout the treatment period, consistent with increased expression in leaves of genes encoding arginine decarboxylase (LeADC. LeADC1), ornithine decarboxylase (LeODC), and Spd synthase (LeSPDS) expressions in tomato leaves throughout the treatment period. Under chilling stress, the Put content increased first, followed by a rise in the Spd content. Exogenously applied SNP did not increase the expression of genes encoding S-adenosylmethionine decarboxylase (LeSAMDC) and Spm synthase (LeSPMS), consistent with the observation that Spm levels remained constant under chilling stress and during the recovery period. In contrast, exogenous Put significantly increased the ABA content and the 9-cis-epoxycarotenoid dioxygenase (LeNCED1) transcript level. Treatment with ABA could alleviate the electrolyte leakage (EL) induced by D-Arg (an inhibitor of Put). Taken together, it is concluded that, under chilling

  6. Highly efficient co-removal of copper (II) and phthalic acid with self-synthesized polyamine resin.

    PubMed

    Ling, Chen; Liu, Fu-Qiang; Long, Chao; Wei, Meng-Meng; Li, Aimin

    2014-01-01

    A novel method was proposed for efficient co-removal of Cu (II) and phthalic acid (PA) using self-synthesized polyamine resin (R-NH(2)). The adsorption properties of R-NH(2) were thoroughly investigated by equilibrium, kinetic and dynamic tests in sole and binary systems at pH 5.0. The Freundlich model was a good fit for all the isotherm data, showing higher Kf values in the binary system than the sole system. The pseudo-second-order kinetic equation showed a better correlation to the experimental data in all cases and PA uptake was much faster than that of Cu (II). R-NH(2) showed highest adsorption capacities to both Cu (II) and PA among the five tested resins. Moreover, the presence of PA markedly enhanced the adsorption of Cu (II), being around 3.5 times of that of the sole system. The adsorption of PA was also slightly increased when Cu (II) was coexistent. Furthermore, using Fourier transform infrared spectrometry (FTIR) and species calculations, possible mechanisms were proposed that Cu (II) coordinated with -NH(2) and negative PA species interacted with -NH(3)(+) by electrostatic attraction. [Cu-PA] complex in the binary system possessed a much higher affinity than free Cu (II) to chelating with -NH(2), resulting in mutual enhancement.

  7. Polyamine intake, dietary pattern, and cardiovascular disease.

    PubMed

    Soda, Kuniyasu

    2010-09-01

    In addition to general lifestyle, a number of foods and dietary patterns, such as the Mediterranean diet (MD), are associated with lower incidences of chronic, age-related diseases, and mortality. We have shown that increased polyamine intake decreases age-associated pathology and increases longevity in mice. Several foods in the MD, such as fruits and legumes, are foods containing high amount of polyamines. Among age-associated conditions, cardiovascular diseases (CVD) are the leading cause of mortality worldwide, and individuals who adhere to a MD have a lower incidence of CVD. The possible contribution of increased polyamine intake to CVD prevention is discussed in this manuscript. Polyamines from food are distributed to all organs and tissues, and long-term intake increases polyamine concentration in blood. Because most polyamines are associated with red and white blood cells, they act to suppress synthesis of pro-inflammatory cytokines and of leukocyte function-associated antigen-1. Foods with anti-inflammatory properties such as n-3 polyunsaturated fatty acids are known to help prevent CVD. Additionally, suppression of de novo polyamine synthesis results from increased polyamines intake, normally synthesized from arginine. This in turn increases availability of arginine for synthesis of nitric oxide, which plays an important role in preserving normal vascular physiology.

  8. 40 CFR 721.9460 - Tall oil fatty acids, reaction products with polyamines, alkyl substituted.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Tall oil fatty acids, reaction... SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.9460 Tall oil fatty acids, reaction... reporting. (1) The chemical substance identified generically as tall oil fatty acids, reaction products...

  9. 40 CFR 721.9460 - Tall oil fatty acids, reaction products with polyamines, alkyl substituted.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Tall oil fatty acids, reaction... SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.9460 Tall oil fatty acids, reaction... reporting. (1) The chemical substance identified generically as tall oil fatty acids, reaction products...

  10. 40 CFR 721.9460 - Tall oil fatty acids, reaction products with polyamines, alkyl substituted.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Tall oil fatty acids, reaction... SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.9460 Tall oil fatty acids, reaction... reporting. (1) The chemical substance identified generically as tall oil fatty acids, reaction products...

  11. 40 CFR 721.9460 - Tall oil fatty acids, reaction products with polyamines, alkyl substituted.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Tall oil fatty acids, reaction... SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.9460 Tall oil fatty acids, reaction... reporting. (1) The chemical substance identified generically as tall oil fatty acids, reaction products...

  12. 40 CFR 721.9460 - Tall oil fatty acids, reaction products with polyamines, alkyl substituted.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Tall oil fatty acids, reaction... SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.9460 Tall oil fatty acids, reaction... reporting. (1) The chemical substance identified generically as tall oil fatty acids, reaction products...

  13. Polyamine analogues bind human serum albumin.

    PubMed

    Beauchemin, R; N'soukpoé-Kossi, C N; Thomas, T J; Thomas, T; Carpentier, R; Tajmir-Riahi, H A

    2007-10-01

    Polyamine analogues show antitumor activity in experimental models, and their ability to alter activity of cytotoxic chemotherapeutic agents in breast cancer is well documented. Association of polyamines with nucleic acids and protein is included in their mechanism of action. The aim of this study was to examine the interaction of human serum albumin (HSA) with several polyamine analogues, such as 1,11-diamino-4,8-diazaundecane (333), 3,7,11,15-tetrazaheptadecane.4HCl (BE-333), and 3,7,11,15,19-pentazahenicosane.5HCl (BE-3333), in aqueous solution at physiological conditions using a constant protein concentration and various polyamine contents (microM to mM). FTIR, UV-visible, and CD spectroscopic methods were used to determine the polyamine binding mode and the effects of polyamine complexation on protein stability and secondary structure. Structural analysis showed that polyamines bind nonspecifically (H-bonding) via polypeptide polar groups with binding constants of K333 = 9.30 x 10(3) M(-1), KBE-333 = 5.63 x 10(2) M(-1), and KBE-3333 = 3.66 x 10(2) M(-1). The protein secondary structure showed major alterations with a reduction of alpha-helix from 55% (free protein) to 43-50% and an increase of beta-sheet from 17% (free protein) to 29-36% in the 333, BE-333, and BE-3333 complexes, indicating partial protein unfolding upon polyamine interaction. HSA structure was less perturbed by polyamine analogues compared to those of the biogenic polyamines.

  14. [Influence of abscisic acid and fluridone on the content of phytohormones and polyamines and the level of oxidative stress in plants of Mesembryanthemum crystallinum L. under salinity].

    PubMed

    Stetsenko, L A; Vedenicheva, N P; Likhnevsky, R V; Kuznetsov, V V

    2015-01-01

    The effect of abscisic acid (ABA) and fluridone on the content of endogenous phytohormones and free polyamines and the intensity of oxidative stress was studied in plants of Mesembryanthemum crystallinum L. under salinity. It was shown that the pretreatment of plant roots with 1 μM ABA, followed by the action of 300 mM NaCl, caused a protective effect and improved the physiological state of the plants, which was manifested in increased biomass and content of available cytokinins and reduced values of the indicators of oxidative stress. It was noted that the inhibitor fluridone reduced the effect of ABA and acted as a pro-oxidant.

  15. Osmotic Stress-Induced Polyamine Accumulation in Cereal Leaves : II. Relation to Amino Acid Pools.

    PubMed

    Flores, H E; Galston, A W

    1984-05-01

    Arginine decarboxylase activity increases 2- to 3-fold in osmotically stressed oat leaves in both light and dark, but putrescine accumulation in the dark is only one-third to one-half of that in light-stressed leaves. If arginine or ornithine are supplied to dark-stressed leaves, putrescine rises to levels comparable to those obtained by incubation under light. Thus, precursor amino acid availability is limiting to the stress response. Amino acid levels change rapidly upon osmotic treatment; notably, glutamic acid decreases with a corresponding rise in glutamine. Difluoromethylarginine (0.01-0.1 millimolar), the enzyme-activated irreversible inhibitor of arginine decarboxylase, prevents the stress-induced putrescine rise, as well as the incorporation of label from [(14)C]arginine, with the expected accumulation of free arginine, but has no effect on the rest of the amino acid pool. The use of specific inhibitors such as alpha-difluoromethylarginine is suggested as probes for the physiological significance of stress responses by plant cells.

  16. Enantioenrichment in sublimed amino acid mixtures.

    PubMed

    Viedma, Cristóbal; Ortiz, José E; de Torres, Trinidad; Cintas, Pedro

    2012-04-14

    A real amplification of an initial enantiomeric excess can be detected when two amino acids are sublimed at high temperature, even if one of the components is a racemic compound that does not convert into a conglomerate by sublimation.

  17. Superlubricity achieved with mixtures of polyhydroxy alcohols and acids.

    PubMed

    Li, Jinjin; Zhang, Chenhui; Luo, Jianbin

    2013-04-30

    In the present work, we show that the superlubricity can be achieved when the polyhydroxy alcohol solutions are mixed with acid solutions. The lowest friction coefficients between 0.003 and 0.006 are obtained on a traditional tribometer with a high pressure under the lubrication of these mixtures. Experimental results indicate that the superlubricity mechanism is in accordance with that under the lubrication of the mixture of glycerol and acid solutions in the study by Li et al. (Li , J. J.; Zhang, C. H.; Ma, L. R.; Liu, Y. H.; Luo, J. B. Superlubricity achieved with mixtures of acids and glycerol. Langmuir 2013, 29, 271-275). It is also found that the superlubricity is closely dependent upon the concentration of polyhydroxy alcohol and the number of hydroxyl groups in the molecular structure of polyhydroxy alcohol. However, the number of carbon atoms and the arrangement of hydroxyl groups in the molecular structure almost have no effect on superlubricity.

  18. Determination of substrate specificity of polyamine transporters in roseobacter species

    NASA Astrophysics Data System (ADS)

    Madhuri, S.; Mou, X.

    2012-12-01

    Polyamines, such as cadaverine, putrescine, spermidine, spermine and norspermine are a class of dissolved organic nitrogen (DON) that is ubiquitously found in marine environments. Intracellular polyamines are important in a variety of biological reactions, such as nucleic acid synthesis and protein synthesis. Free polyamines in seawater can be transported into bacterial cells by ABC transporter systems, each of which consists of four components including one substrate binding protein, one ATPase and two permeases. In silico analysis of marine bacterial genomes has revealed that roseobacter, a numerically and ecologically important taxa of marine bacteria, have at least two sets of polyamine transporter genes. This study was to examine the potential preference of roseobacter to different polyamine compounds and the substrate specificity of different polyamine transporters. Eleven roseobacter species, which genomes have been sequenced, were grown in defined media supplied with single polyamine compound as the sole carbon and nitrogen source. Growth assay showed a small number of roseobacter isolates to be generalist showing no preference among the tested polyamines (Ruegeria pomeroyi DSS-3, Roseovarius sp. TM1035, Roseovarius nubinhibens ISM, Jannaschia sp. CCS1 and Sagittula stellata E-37), whereas other isolates were specilists and were specific on polyamine compounds (Roseobacter sp. CCS2 and Roseobacter denitrificans OCh 114). Primers that probe poly-1 and pot-D genes, the two genes that encode common polyamine-binding genes of polyamine transporter systems were designed using net primer and primer design program. The specificity of the primers was validated by PCR followed by amplicon sequencing. Single step reverse transcription quantitative polymerase chain reactions (RT-qPCR) was performed to investigate substrate specificity of poly-1 and pot-D genes. Key-words Roseobacter, polyamine, polyamine transporter, dissolved organic nitrogen

  19. Effects of S-adenosylmethionine decarboxylase, polyamines, amino acids, and weak bases (amines and ammonia) on development and ribosomal RNA synthesis in Xenopus embryos.

    PubMed

    Shiokawa, Koichiro; Aso, Mai; Kondo, Takeshi; Takai, Jun-Ichi; Yoshida, Junki; Mishina, Takamichi; Fuchimukai, Kota; Ogasawara, Tsukasa; Kariya, Taro; Tashiro, Kosuke; Igarashi, Kazuei

    2010-02-01

    We have been studying control mechanisms of gene expression in early embryogenesis in a South African clawed toad Xenopus laevis, especially during the period of midblastula transition (MBT), or the transition from the phase of active cell division (cleavage stage) to the phase of extensive morphogenesis (post-blastular stages). We first found that ribosomal RNA synthesis is initiated shortly after MBT in Xenopus embryos and those weak bases, such as amines and ammonium ion, selectively inhibit the initiation and subsequent activation of rRNA synthesis. We then found that rapidly labeled heterogeneous mRNA-like RNA is synthesized in embryos at pre-MBT stage. We then performed cloning and expression studies of several genes, such as those for activin receptors, follistatin and aldolases, and then reached the studies of S-adenosylmethionine decarboxylase (SAMDC), a key enzyme in polyamine metabolism. Here, we cloned a Xenopus SAMDC cDNA and performed experiments to overexpress the in vitro-synthesized SAMDC mRNA in Xenopus early embryos, and found that the maternally preset program of apoptosis occurs in cleavage stage embryos, which is executed when embryos reach the stage of MBT. In the present article, we first summarize results on SAMDC and the maternal program of apoptosis, and then describe our studies on small-molecular-weight substances like polyamines, amino acids, and amines in Xenopus embryos. Finally, we summarize our studies on weak bases, especially on ammonium ion, as the specific inhibitor of ribosomal RNA synthesis in Xenopus embryonic cells.

  20. Impact of Cell-free Supernatant of Lactic Acid Bacteria on Putrescine and Other Polyamine Formation by Foodborne Pathogens in Ornithine Decarboxylase Broth.

    PubMed

    Ozogul, Fatih; Tabanelli, Giulia; Toy, Nurten; Gardini, Fausto

    2015-06-24

    Conversion of ornithine to putrescine by Salmonella Paratyphi A, Listeria monocytogenes, Staphylococcus aureus, and Escherichia coli was investigated in ornithine decarboxylase broth (ODB) using cell-free supernatants (CFSs) obtained from Leuconostoc mesenterodies subsp. cremoris, Pediococcus acidilactici, Lactococcus lactis subsp. lactis, Streptococcus thermophilus. Two groups of cell-free supernatants (25 or 50%) and control (only ODB) were prepared to investigate putrescine (PUT) and other polyamine formation by foodborne pathogens (FBPs). Significant differences (p < 0.05) were observed among the species for each amine. All of the CFSs reduced the formation of PUT by ≥65%. The production of cadaverine (CAD) was scarcely affected by the presence of CFSs, with the exception of the samples inoculated with L. monocytogenes. The variation in polyamine was found with respect to the control samples. Spermidine (SPD) was produced in lower amount in many samples, especially in Gram-negative FBPs, whereas spermine (SPN) increased drastically in the major part of the samples concerning the control. Histamine (HIS) was characterized by a marked concentration decrease in all of the samples, and tyramine (TYR) was accumulated in very low concentrations in the controls. Therefore, the ability of bacteria to produce certain biogenic amines such as HIS, TYR, PUT, and CAD has been studied to assess their risk and prevent their formation in food products. The results obtained from this study concluded that the lactic acid bacteria (LAB) strains with non-decarboxylase activity are capable of avoiding or limiting biogenic amine formation by FBP.

  1. Exogenous polyamines elicit herbivore-induced volatiles in lima bean leaves: involvement of calcium, H2O2 and Jasmonic acid.

    PubMed

    Ozawa, Rika; Bertea, Cinzia M; Foti, Maria; Narayana, Ravishankar; Arimura, Gen-Ichiro; Muroi, Atsushi; Horiuchi, Jun-Ichiro; Nishioka, Takaaki; Maffei, Massimo E; Takabayashi, Junji

    2009-12-01

    We investigated the role of polyamines (PAs) in lima bean (Phaseolus lunatus) leaves on the production of herbivorous mite (Tetranychus urticae)-induced plant volatiles that attract carnivorous natural enemies of the herbivores. To do this, we focused on the effects of the exogenous PAs [cadaverine, putrescine, spermidine and spermine (Spm)] on the production of volatiles, H(2)O(2) and jasmonic acid (JA) and the levels of defensive genes, cytosolic calcium and reactive oxygen species (ROS). Among the tested PAs, Spm was the most active in inducing the production of volatile terpenoids known to be induced by T. urticae. An increase in JA levels was also found after Spm treatment, indicating that Spm induces the biosynthesis of JA, which has been shown elsewhere to regulate the production of some volatile terpenoids. Further, treatment with JA and Spm together resulted in greater volatile emission than that with JA alone. In a Y-tube olfactometer, leaves treated with Spm + JA attracted more predatory mites (Phytoseiulus persimilis) than those treated with JA alone. After treatment with Spm + JA, no effects were found on the enzyme activity of polyamine oxidase and copper amine oxidase. However, induction of calcium influx and ROS production, and increased enzyme activities and gene expression for NADPH oxidase complex, superoxide dismutase, catalase, ascorbate peroxidase, glutathione reductase and glutathione peroxidase were found after treatment with Spm + JA. These results indicate that Spm plays an important role in the production of T. urticae-induced lima bean leaf volatiles.

  2. Polyamine catabolism and disease.

    PubMed

    Casero, Robert A; Pegg, Anthony E

    2009-07-15

    In addition to polyamine homoeostasis, it has become increasingly clear that polyamine catabolism can play a dominant role in drug response, apoptosis and the response to stressful stimuli, and contribute to the aetiology of several pathological states, including cancer. The highly inducible enzymes SSAT (spermidine/spermine N1-acetyltransferase) and SMO (spermine oxidase) and the generally constitutively expressed APAO (N1-acetylpolyamine oxidase) appear to play critical roles in many normal and disease processes. The dysregulation of polyamine catabolism frequently accompanies several disease states and suggests that such dysregulation may both provide useful insight into disease mechanism and provide unique druggable targets that can be exploited for therapeutic benefit. Each of these enzymes has the potential to alter polyamine homoeostasis in response to multiple cell signals and the two oxidases produce the reactive oxygen species H2O2 and aldehydes, each with the potential to produce pathological states. The activity of SSAT provides substrates for APAO or substrates for the polyamine exporter, thus reducing the intracellular polyamine concentration, the net effect of which depends on the magnitude and rate of any increase in SSAT. SSAT may also influence cellular metabolism via interaction with other proteins and by perturbing the content of acetyl-CoA and ATP. The goal of the present review is to cover those aspects of polyamine catabolism that have an impact on disease aetiology or treatment and to provide a solid background in this ever more exciting aspect of polyamine biology.

  3. Polyamine catabolism and disease

    PubMed Central

    CASERO, Robert A.; PEGG, Anthony E.

    2009-01-01

    In addition to polyamine homeostasis, it has become increasingly clear that polyamine catabolism can play a dominant role in drug response, apoptosis, response to stressful stimuli, and contribute to the etiology of several pathological states, including cancer. The highly inducible enzymes spermidine/spermine N1-acetyltransferase (SSAT) and spermine oxidase (SMO), and, the generally constitutively expressed N1-acetylpolyamine oxidase (APAO), appear to play critical roles in many normal and disease processes. The dysregulation of polyamine catabolism frequently accompanies several disease states and suggests that such dysregulation may both provide useful insight into disease mechanism and provide unique drugable targets that can be exploited for therapeutic benefit. Each of these enzymes has the potential to alter polyamine homeostasis in response to multiple cell signals and the two oxidases produce the reactive oxygen species H2O2 and aldehydes, each with the potential to produce pathologies. The activity of SSAT has the potential to provide substrates for APAO or substrates for the polyamine exporter, thus reducing the intracellular polyamine concentration, the net effect of which depends on the magnitude and rate of any increase in SSAT. SSAT may also influence cellular metabolism via interaction with other proteins and by perturbing the content of acetyl CoA and ATP. The goal of this review is to cover those aspects of polyamine catabolism that have potential to impact disease etiology or treatment and to provide a solid background in this ever more exciting aspect of polyamine biology. PMID:19589128

  4. The Form in Which Nitrogen Is Supplied Affects the Polyamines, Amino Acids, and Mineral Composition of Sweet Pepper Fruit under an Elevated CO2 Concentration.

    PubMed

    Piñero, Maria C; Otálora, Ginés; Porras, Manuel E; Sánchez-Guerrero, Mari C; Lorenzo, Pilar; Medrano, Evangelina; Del Amor, Francisco M

    2017-02-01

    We investigated the effect of supplying nitrogen, as NO3(-) or as NO3(-)/NH4(+), on the composition of fruits of sweet pepper (Capsicum annuum L. cv. Melchor) plants grown with different CO2 concentrations ([CO2]): ambient or elevated (800 μmol mol(-1)). The results show that the application of NH4(+) and high [CO2] affected the chroma related to the concentrations of chlorophylls. The concentrations of Ca, Cu, Mg, P, and Zn were significantly reduced in the fruits of plants nourished with NH4(+), the loss of Fe being more dramatic at increased [CO2], which was also the case with the protein concentration. The concentration of total phenolics was increased by NH4(+), being unaffected by [CO2]. Globally, the NH4(+) was the main factor that affected fruit free amino acid concentrations. Polyamines were affected differently: putrescine was increased by elevated [CO2], while the response of cadaverine depended on the form of N supplied.

  5. Superlubricity achieved with mixtures of acids and glycerol.

    PubMed

    Li, Jinjin; Zhang, Chenhui; Ma, Liran; Liu, Yuhong; Luo, Jianbin

    2013-01-08

    In this work, superlubricity between glass and Si(3)N(4) surfaces lubricated by mixtures of acid solutions and glycerol solutions has been found by using a traditional tribometer. Ultralow friction coefficients of between 0.004 and 0.006 were obtained after a running-in period. Related experiments indicate that the hydrogen ions in the mixtures play an important role in achieving superlubricity. Moreover, the ultralow friction is also closely related to the pH value of the acid and the concentration of glycerol. According to these results, the possible superlubricity mechanism has been revealed, which is attributed to a fluid-hydrated water layer between the hydrogen-bonded networks of glycerol and water molecules on the positively charged surfaces.

  6. Mammalian Polyamine Metabolism and Function

    PubMed Central

    Pegg, Anthony E.

    2009-01-01

    Summary Polyamines are ubiquitous small basic molecules that play multiple essential roles in mammalian physiology. Their cellular content is highly regulated and there is convincing evidence that altered metabolism is involvement in many disease states. Drugs altering polyamine levels may therefore have a variety of important targets. This review will summarize the current state of understanding of polyamine metabolism and function, the regulation of polyamine content, and heritable pathological conditions that may be derived from altered polyamine metabolism. PMID:19603518

  7. Binding of biogenic and synthetic polyamines to β-lactoglobulin.

    PubMed

    Essemine, J; Hasni, I; Carpentier, R; Thomas, T J; Tajmir-Riahi, H A

    2011-08-01

    The bindings of biogenic polyamines spermine (spm), spermidine (spmd) and synthetic polyamines 3,7,11,15-tetrazaheptadecane·4HCl (BE-333) and 3,7,11,15,19-pentazahenicosane·5HCl (BE-3333) with β-lactoglobulin (β-LG) were determined in aqueous solution. FTIR, UV-vis, CD and fluorescence spectroscopic methods as well as molecular modeling were used to determine the polyamine binding sites and the effect of polyamine complexation on protein stability and secondary structure. Structural analysis showed that polyamines bind β-LG via both hydrophilic and hydrophobic contacts. Stronger polyamine-protein complexes formed with synthetic polyamines than biogenic polyamines, with overall binding constants of K(spm-β-LG)=3.2(±0.6)×10(4) M(-1), K(spmd-β-LG)=1.8(±0.5)×10(4) M(-1), K(BE-333-β-LG)=5.8(±0.3)×10(4) M(-1) and K(BE-3333-β-LG)=6.2(±0.05)×10(4) M(-1). Molecular modeling showed the participation of several amino acids in the polyamine complexes with the following order of polyamine-protein binding affinity: BE-3333>BE-333>spermine>spermidine, which correlates with their positively charged amino group content. Alteration of protein conformation was observed with a reduction of β-sheet from 57% (free protein) to 55-51%, and a major increase of turn structure from 13% (free protein) to ∼21% in the polyamine-β-LG complexes, indicating a partial protein unfolding.

  8. Epibrassinolide ameliorates Cr (VI) stress via influencing the levels of indole-3-acetic acid, abscisic acid, polyamines and antioxidant system of radish seedlings.

    PubMed

    Choudhary, Sikander Pal; Kanwar, Mukesh; Bhardwaj, Renu; Gupta, B D; Gupta, R K

    2011-07-01

    The present investigation determined the effects of epibrassinolide (EBL) on the levels of indole-3-acetic acid (IAA), abscisic acid (ABA), and polyamine (PA) and antioxidant potential of 7-d old Raphanus sativus L. cv. 'Pusa chetki' seedlings grown under Cr (VI) metal stress. Reduced titers of free (0.767 μg g(-1) FW) and bound (0.545 μg g(-1) FW) IAA in Cr (VI) stressed seedlings were observed over untreated control. Supplementations of EBL to Cr (VI) stressed seedlings were able to enhance both free (2.14-5.68 μg g(-1) FW) and bound IAA (2.45-7.78 μg g(-1) FW) concentrations in comparison to Cr (VI) metal treatment alone. Significant rise in free (13.49 μg g(-1) FW) and bound (12.17 μg g(-1) FW) ABA contents were noticed for Cr (VI) stressed seedlings when compared to untreated control. No significant increase in ABA contents were recorded for Cr (VI) stressed seedlings upon supplementation with EBL over Cr (VI) treatment alone. A significant increase in Put (18.40 μg g(-1) FW) and Cad (9.08 μg g(-1) FW) contents were found for 10(-9)M EBL plus Cr (VI) metal treatments when compared to Cr (VI) treatment alone. Spermidine (Spd) contents were found to decline significantly for EBL treatment alone or when supplemented with Cr (VI) treatments over untreated controls and Cr (VI) treatment alone. Antioxidant levels were found to enhance, with glutathione (57.98 mg g(-1) FW), proline (4.97 mg g(-1) FW), glycinebetaine (39.01 μmol mL(-1)), ascorbic acid (3.17 mg g(-1) FW) and phytochelatins (65.69 μmol g(-1) FW) contents noted for EBL supplemented to Cr (VI) metal solution over Cr (VI) treatment alone. Reduced activities of guaiacol peroxidase (0.391 U mg(-1) protein) and catalase (0.221 U mg(-1) protein) and enhanced activities of glutathione reductase (7.14 U mg(-1) protein), superoxide dismutase (15.20 U mg(-1) protein) and ascorbate peroxidase (4.31 U mg(-1) protein) were observed in seedlings treated with EBL plus Cr (VI) over Cr metal treatment alone

  9. Control of Meloidogyne incognita Using Mixtures of Organic Acids

    PubMed Central

    Seo, Yunhee; Kim, Young Ho

    2014-01-01

    This study sought to control the root-knot nematode (RKN) Meloidogyne incognita using benign organo-chemicals. Second-stage juveniles (J2) of RKN were exposed to dilutions (1.0%, 0.5%, 0.2%, and 0.1%) of acetic acid (AA), lactic acid (LA), and their mixtures (MX). The nematode bodies were disrupted severely and moderately by vacuolations in 0.5% of MX and single organic acids, respectively, suggesting toxicity of MX may be higher than AA and LA. The mortality of J2 was 100% at all concentrations of AA and MX and only at 1.0% and 0.5% of LA, which lowered slightly at 0.2% and greatly at 0.1% of LA. This suggests the nematicidal activity of MX may be mostly derived from AA together with supplementary LA toxicity. MX was applied to chili pepper plants inoculated with about 1,000 J2, for which root-knot gall formations and plant growths were examined 4 weeks after inoculation. The root gall formation was completely inhibited by 0.5% MX and standard and double concentrations of fosthiazate; and inhibited 92.9% and 57.1% by 0.2% and 0.1% MX, respectively. Shoot height, shoot weight, and root weight were not significantly (P ≤ 0.05) different among all treatments and the untreated and non-inoculated controls. All of these results suggest that the mixture of the organic acids may have a potential to be developed as an eco-friendly nematode control agent that needs to be supported by the more nematode control experiments in fields. PMID:25506312

  10. Benzoic Acid and Chlorobenzoic Acids: Thermodynamic Study of the Pure Compounds and Binary Mixtures With Water.

    PubMed

    Reschke, Thomas; Zherikova, Kseniya V; Verevkin, Sergey P; Held, Christoph

    2016-03-01

    Benzoic acid is a model compound for drug substances in pharmaceutical research. Process design requires information about thermodynamic phase behavior of benzoic acid and its mixtures with water and organic solvents. This work addresses phase equilibria that determine stability and solubility. In this work, Perturbed-Chain Statistical Associating Fluid Theory (PC-SAFT) was used to model the phase behavior of aqueous and organic solutions containing benzoic acid and chlorobenzoic acids. Absolute vapor pressures of benzoic acid and 2-, 3-, and 4-chlorobenzoic acid from literature and from our own measurements were used to determine pure-component PC-SAFT parameters. Two binary interaction parameters between water and/or benzoic acid were used to model vapor-liquid and liquid-liquid equilibria of water and/or benzoic acid between 280 and 413 K. The PC-SAFT parameters and 1 binary interaction parameter were used to model aqueous solubility of the chlorobenzoic acids. Additionally, solubility of benzoic acid in organic solvents was predicted without using binary parameters. All results showed that pure-component parameters for benzoic acid and for the chlorobenzoic acids allowed for satisfying modeling phase equilibria. The modeling approach established in this work is a further step to screen solubility and to predict the whole phase region of mixtures containing pharmaceuticals.

  11. Polyamines and Root Formation in Mung Bean Hypocotyl Cuttings 1

    PubMed Central

    Friedman, Ra'Anan; Altman, Arie; Bachrach, Uriel

    1982-01-01

    The effect of several polyamines (putrescine, spermidine, and spermine), their precursors (l-arginine and l-ornithine), and some analogs and metabolic inhibitors (l-canavanine, l-canaline, and methylglyoxal-bis [guanylhydrazone]) on root formation have been studied in mung bean (Vigna radiata [L.] Wilczek) hypocotyl cuttings. Exogenously applied polyamines did not promote adventitious root formation. Rooting was inhibited by l-canavanine and l-canaline, and this inhibition was reversed by the corresponding amino acids l-arginine and l-ornithine. Methylglyoxal-bis (guanylhydrazone), an inhibitor of S-adenosylmethionine decarboxylase and polyamine biosynthesis, was also found to inhibit root formation. All compounds at concentrations of >10−4 molarity completely inhibited natural root formation, whereas at <10−5 molarity only the indole-butyric acid-induced root formation was inhibited. Indole-butyric acid-induced root formation was accompanied by a considerable increase in polyamine levels, more than 2-fold of the control. Whereas senescing (unrooted) cuttings evinced a rapid decline in polyamine content during 48 hours, indole-butyric acid treatment resulted in elevated levels of putrescine and increased putrescine to spermidine ratio. The changes in polyamines were dependent on indole-butyric acid concentration and were organ specific. Images Fig. 1 PMID:16662586

  12. Polyamines in tea processing.

    PubMed

    Palavan-Unsal, Narcin; Arisan, Elif Damla; Terzioglu, Salih

    2007-06-01

    The distribution of dietary polyamines, putrescine, spermidine and spermine, was determined during processing of Camellia sinensis. Black tea manufacture is carried by a series of processes on fresh tea leaves involving withering, rolling, fermentation, drying and sieving. The aim of this research was to determine the effect of tea processing on the polyamine content in relation with antioxidant enzymes, superoxide dismutase, lipid peroxidase and glutathione peroxidase. Before processing, the spermine content was much higher than the putrescine and spermidine content in green tea leaves. Spermine was significantly decreased during processing while the putrescine and spermine contents increased during withered and rolling and decreased in the following stages. The superoxide dismutase activity increased at the withering stage and declined during processing. The transcript level of the polyamine biosynthesis-responsible enzyme ornithine decarboxylase was reduced during each processing step. This study reveals the importance of protection of nutritional compounds that are essential for health during the manufacturing process.

  13. Aggregation behavior of Brij-35/perfluorononanoic acid mixtures.

    PubMed

    Torres, María Florencia; Sales, Pablo S; de Rossi, Rita H; Fernández, Mariana A

    2010-12-07

    The mixed system of a nonionic hydrocarbon surfactant, polyoxyethylene (23) lauryl ether (Brij-35), and a perfluorinated surfactant, perfluorononanoic acid, was investigated by a combination of methods. The critical micelle concentrations (cmc's) have been determined over a wide range of sample compositions by fluorescence and UV-visible spectrophotometry using pyrene and N-(4-nitrophenyl) perfluorononanamide, respectively, as molecular probes. The values of the cmc's obtained were considerably different with the two techniques employed. Measurements of the (19)F nuclear magnetic resonance chemical shift of the same mixtures showed two breaks in the plots of Δδ(f) versus molar fraction of the perfluorinated surfactant. Conductivity and surface tension measurements also showed two breaks. The behavior is attributed to the formation of mixed micelles that change their composition when the fraction of the fluorinated compound increases and some segregation of the fluorinated compound takes place at a high total surfactant concentration.

  14. 40 CFR 721.10410 - Polyether ester acid compound with a polyamine amide (generic) (P-05-714).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Polyether ester acid compound with a... Significant New Uses for Specific Chemical Substances § 721.10410 Polyether ester acid compound with a.... (1) The chemical substance identified generically as polyether ester acid compound with a...

  15. 40 CFR 721.10410 - Polyether ester acid compound with a polyamine amide (generic) (P-05-714).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Polyether ester acid compound with a... Significant New Uses for Specific Chemical Substances § 721.10410 Polyether ester acid compound with a.... (1) The chemical substance identified generically as polyether ester acid compound with a...

  16. 40 CFR 721.10410 - Polyether ester acid compound with a polyamine amide (generic) (P-05-714).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Polyether ester acid compound with a... Significant New Uses for Specific Chemical Substances § 721.10410 Polyether ester acid compound with a.... (1) The chemical substance identified generically as polyether ester acid compound with a...

  17. Peptoids and polyamines going sweet: Modular synthesis of glycosylated peptoids and polyamines using click chemistry

    PubMed Central

    Fürniss, Daniel; Mack, Timo; Hahn, Frank; Vollrath, Sidonie B L; Koroniak, Katarzyna

    2013-01-01

    Summary Sugar moieties are present in a wide range of bioactive molecules. Thus, having versatile and fast methods for the decoration of biomimetic molecules with sugars is of fundamental importance. The glycosylation of peptoids and polyamines as examples of such biomimetic molecules is reported here. The method uses Cu-catalyzed azide alkyne cycloaddition to promote the reaction of azidosugars with either polyamines or peptoids. In addition, functionalized nucleic acids were attached to polyamines via the same route. Based on a modular solid-phase synthesis of peralkynylated peptoids with up to six alkyne groups, the latter were modified with azidosugar building blocks by using copper-catalyzed azide alkyne cycloadditions. In addition, the up-scaling of some particular azide-modified sugars is described. PMID:23399592

  18. Polyamines and Their Metabolites as Diagnostic Markers of Human Diseases

    PubMed Central

    Park, Myung Hee; Igarashi, Kazuei

    2013-01-01

    Polyamines, putrescine, spermidine and spermine, are ubiquitous in living cells and are essential for eukaryotic cell growth. These polycations interact with negatively charged molecules such as DNA, RNA, acidic proteins and phospholipids and modulate various cellular functions including macromolecular synthesis. Dysregulation of the polyamine pathway leads to pathological conditions including cancer, inflammation, stroke, renal failure and diabetes. Increase in polyamines and polyamine synthesis enzymes is often associated with tumor growth, and urinary and plasma contents of polyamines and their metabolites have been investigated as diagnostic markers for cancers. Of these, diacetylated derivatives of spermidine and spermine are elevated in the urine of cancer patients and present potential markers for early detection. Enhanced catabolism of cellular polyamines by polyamine oxidases (PAO), spermine oxidase (SMO) or acetylpolyamine oxidase (AcPAO), increases cellular oxidative stress and generates hydrogen peroxide and a reactive toxic metabolite, acrolein, which covalently incorporates into lysine residues of cellular proteins. Levels of protein-conjuagated acrolein (PC-Acro) and polyamine oxidizing enzymes were increased in the locus of brain infarction and in plasma in a mouse model of stroke and also in the plasma of stroke patients. When the combined measurements of PC-Acro, interleukin 6 (IL-6), and C-reactive protein (CRP) were evaluated, even silent brain infarction (SBI) was detected with high sensitivity and specificity. Considering that there are no reliable biochemical markers for early stage of stroke, PC-Acro and PAOs present promising markers. Thus the polyamine metabolites in plasma or urine provide useful tools in early diagnosis of cancer and stroke. PMID:24009852

  19. Acid-base titrations by stepwise addition of equal volumes of titrant with special reference to automatic titrations-II Theory of titration of mixtures of acids, polyprotic acids, acids in mixture with weak bases, and ampholytes.

    PubMed

    Pehrsson, L; Ingman, F; Johansson, S

    A general method for evaluating titration data for mixtures of acids and for acids in mixture with weak bases is presented. Procedures are given that do not require absolute [H]-data, i.e., relative [H]-data may be used. In most cases a very rough calibration of the electrode system is enough. Further, for simple systems, very approximate values of the stability constants are sufficient. As examples, the titration of the following are treated in some detail: a mixture of two acids, a diprotic acid, an acid in presence of its conjugate base, and an ampholyte.

  20. Silicon-mediated changes in polyamine and 1-aminocyclopropane-1-carboxylic acid are involved in silicon-induced drought resistance in Sorghum bicolor L.

    PubMed

    Yin, Lina; Wang, Shiwen; Liu, Peng; Wang, Wenhua; Cao, Dan; Deng, Xiping; Zhang, Suiqi

    2014-07-01

    The fact that silicon application alleviates drought stress has been widely reported, but the mechanism it underlying remains unclear. Here, morphologic and physiological changes were investigated in sorghum (Sorghum bicolor L.) seedlings treated with silicon and exposed to PEG-simulated drought stress for seven days. Drought stress dramatically decreased growth parameters (biomass, root/shoot ratio, leaf area, chlorophyll concentration and photosynthetic rate), while silicon application reduced the drought-induced decreases in those parameters. Leaf relative water content and transpiration rate were maintained at high levels compared to those in seedlings without silicon. The soluble sugar contents were increased, but the proline contents and the osmotic potential were decreased, showing that osmotic adjustment did not contribute to the silicon induced-drought resistance. Furthermore, levels of both free and conjugated polyamines (PAs) levels, including putrescine, spermidine and spermine, were all found to be increased by silicon under drought stress both in leaf and root. Meanwhile, 1-aminocyclopropane-1-carboxylic acid (ACC), the precursor of ethylene, was markedly decreased by supplemental silicon. Several key PA synthesis genes were upregulated by silicon under drought stress. These results suggest that silicon improves sorghum drought resistance by mediating the balance of PAs and ethylene levels. In leaf, the increased PAs and decreased ACC help to retard leaf senescence. In root, the balance between PAs and ACC participates in the modulation of root plasticity, increases the root/shoot ratio, and contributes to an increase in water uptake. These results suggest that silicon increases drought resistance through regulating several important physiological processes in plants.

  1. Evolutionary relationship between 5+5 and 7+7 inverted repeat folds within the amino acid-polyamine-organocation superfamily.

    PubMed

    Västermark, Åke; Saier, Milton H

    2014-02-01

    Evidence has been presented that 5+5 TMS and 7+7 TMS inverted repeat fold transporters are members of a single superfamily named the Amino acid-Polyamine-organoCation (APC) superfamily. However, the evolutionary relationship between the 5+5 and the 7+7 topological types has not been established. We have identified a common fold, consisting of a spiny membrane helix/sheet, followed by a U-like structure and a V-like structure that is recurrent between domain duplicated units of 5+5 and 7+7 inverted repeat folds. This fold is found in the following protein structures: AdiC, ApcT, LeuT, Mhp1, BetP, CaiT, and SglT (all 5+5 TMS repeats), as well as UraA and SulP (7+7 TMS repeats). AdiC, LeuT and Mhp1 have two extra TMSs after the second duplicated domain, SglT has four extra C-terminal TMSs, and BetP has two extra TMSs before the first duplicated domain. UraA and SulP on the other hand have two extra TMSs at the N-terminus of each duplicated domain unit. These observations imply that multiple hairpin and domain duplication events occurred during the evolution of the APC superfamily. We suggest that the five TMS architecture was primordial and that families gained two TMSs on either side of this basic structure via dissimilar hairpin duplications either before or after intragenic duplication. Evidence for homology between TMSs 1-2 of AdiC and TMSs 1-2 and 3-4 of UraA suggests that the 7+7 topology arose via an internal duplication of the N-terminal hairpin loop within the five TMS repeat unit followed by duplication of the 7 TMS domain.

  2. Polyamines and nonmelanoma skin cancer

    SciTech Connect

    Gilmour, Susan K.

    2007-11-01

    Elevated levels of polyamines have long been associated with skin tumorigenesis. Tightly regulated metabolism of polyamines is critical for cell survival and normal skin homeostasis, and these controls are dysregulated in skin tumorigenesis. A key enzyme in polyamine biosynthesis, ornithine decarboxylase (ODC) is upregulated in skin tumors compared to normal skin. Use of transgenic mouse models has demonstrated that polyamines play an essential role in the early promotional phase of skin tumorigenesis. The formation of skin tumors in these transgenic mice is dependent upon polyamine biosynthesis, especially putrescine, since treatment with inhibitors of ODC activity blocks the formation of skin tumors and causes the rapid regression of existing tumors. Although the mechanism by which polyamines promote skin tumorigenesis are not well understood, elevated levels of polyamines have been shown to stimulate epidermal proliferation, alter keratinocyte differentiation status, increase neovascularization, and increase synthesis of extracellular matrix proteins in a manner similar to that seen in wound healing. It is becoming increasingly apparent that elevated polyamine levels activate not only epidermal cells but also underlying stromal cells in the skin to promote the development and progression of skin tumors. The inhibition of polyamine biosynthesis has potential to be an effective chemoprevention strategy for nonmelanoma skin cancer.

  3. Kinetic and phylogenetic analysis of plant polyamine uptake transporters.

    PubMed

    Mulangi, Vaishali; Chibucos, Marcus C; Phuntumart, Vipaporn; Morris, Paul F

    2012-10-01

    The rice gene Polyamine Uptake Transporter1 (PUT1) was originally identified based on its homology to the polyamine uptake transporters LmPOT1 and TcPAT12 in Leishmania major and Trypanosoma cruzi, respectively. Here we show that five additional transporters from rice and Arabidopsis that cluster in the same clade as PUT1 all function as high affinity spermidine uptake transporters. Yeast expression assays of these genes confirmed that uptake of spermidine was minimally affected by 166 fold or greater concentrations of amino acids. Characterized polyamine transporters from both Arabidopsis thaliana and Oryza sativa along with the two polyamine transporters from L. major and T. cruzi were aligned and used to generate a hidden Markov model. This model was used to identify significant matches to proteins in other angiosperms, bryophytes, chlorophyta, discicristates, excavates, stramenopiles and amoebozoa. No significant matches were identified in fungal or metazoan genomes. Phylogenic analysis showed that some sequences from the haptophyte, Emiliania huxleyi, as well as sequences from oomycetes and diatoms clustered closer to sequences from plant genomes than from a homologous sequence in the red algal genome Galdieria sulphuraria, consistent with the hypothesis that these polyamine transporters were acquired by horizontal transfer from green algae. Leishmania and Trypansosoma formed a separate cluster with genes from other Discicristates and two Entamoeba species. We surmise that the genes in Entamoeba species were acquired by phagotrophy of Discicristates. In summary, phylogenetic and functional analysis has identified two clades of genes that are predictive of polyamine transport activity.

  4. Polyamine Transporters and Polyamines Increase Furfural Tolerance during Xylose Fermentation with Ethanologenic Escherichia coli Strain LY180

    PubMed Central

    Geddes, Ryan D.; Wang, Xuan; Yomano, Lorraine P.; Miller, Elliot N.; Zheng, Huabao; Shanmugam, Keelnatham T.

    2014-01-01

    Expression of genes encoding polyamine transporters from plasmids and polyamine supplements increased furfural tolerance (growth and ethanol production) in ethanologenic Escherichia coli LY180 (in AM1 mineral salts medium containing xylose). This represents a new approach to increase furfural tolerance and may be useful for other organisms. Microarray comparisons of two furfural-resistant mutants (EMFR9 and EMFR35) provided initial evidence for the importance of polyamine transporters. Each mutant contained a single polyamine transporter gene that was upregulated over 100-fold (microarrays) compared to that in the parent LY180, as well as a mutation that silenced the expression of yqhD. Based on these genetic changes, furfural tolerance was substantially reconstructed in the parent, LY180. Deletion of potE in EMFR9 lowered furfural tolerance to that of the parent. Deletion of potE and puuP in LY180 also decreased furfural tolerance, indicating functional importance of the native genes. Of the 8 polyamine transporters (18 genes) cloned and tested, half were beneficial for furfural tolerance (PotE, PuuP, PlaP, and PotABCD). Supplementing AM1 mineral salts medium with individual polyamines (agmatine, putrescine, and cadaverine) also increased furfural tolerance but to a smaller extent. In pH-controlled fermentations, polyamine transporter plasmids were shown to promote the metabolism of furfural and substantially reduce the time required to complete xylose fermentation. This increase in furfural tolerance is proposed to result from polyamine binding to negatively charged cellular constituents such as nucleic acids and phospholipids, providing protection from damage by furfural. PMID:25063650

  5. Polyamines and Gut Mucosal Homeostasis

    PubMed Central

    Timmons, Jennifer; Chang, Elizabeth T.; Wang, Jian-Ying; Rao, Jaladanki N.

    2012-01-01

    The epithelium of gastrointestinal (GI) mucosa has the most rapid turnover rate of any tissue in the body and its integrity is preserved through the dynamic balance between cell migration, proliferation, growth arrest and apoptosis. To maintain tissue homeostasis of the GI mucosa, the rates of epithelial cell division and apoptosis must be highly regulated by various extracellular and intracellular factors including cellular polyamines. Natural polyamines spermidine, spermine and their precursor putrescine, are organic cations in eukaryotic cells and are implicated in the control of multiple signaling pathways and distinct cellular functions. Normal intestinal epithelial growth depends on the available supply of polyamines to the dividing cells in the crypts, and polyamines also regulate intestinal epithelial cell (IEC) apoptosis. Although the specific molecular processes controlled by polyamines remains to be fully defined, increasing evidence indicates that polyamines regulate intestinal epithelial integrity by modulating the expression of various growth-related genes. In this review, we will extrapolate the current state of scientific knowledge regarding the roles of polyamines in gut mucosal homeostasis and highlight progress in cellular and molecular mechanisms of polyamines and their potential clinical applications. PMID:25237589

  6. Developmental Toxicity of Perfluoroalkyl Acid Mixtures in CD-1 Mice

    EPA Science Inventory

    Perfluorooctanoic acid (PFOA), perfluorooctane sulfonate (PFOS) and perfluorononanoic acid (PFNA) belong to a family of fluoro-organic compounds known as perfluoroalkyl acids (PFAAs). PFAAs have been widely used in industrial and commercial applications, and have been found to be...

  7. Kinetics of sorption of Cu(II)-ethylenediaminetetraacetic acid chelated anions on cross-linked, polyaminated chitosan beads

    SciTech Connect

    Juang, R.S.; Ju, C.Y.

    1998-08-01

    Rates of sorption of Cu(II)-ethylenediaminetetraacetic acid (EDTA) chelated anions from aqueous solutions on cross-linked, poly(ethylenimine) (PEI)-modified chitosan beads were measured in a batch stirred vessel. All experiments were carried out in an equimolar solution of Cu(II) and EDTA (0.47--3.15 mol/m{sup 3}). It was shown that the rates of sorption increased with an increase in the initial concentration of Cu(II), pH, and temperature but decreased with an increase in the molecular weight of PEI introduced in the beads. The widely used homogeneous diffusion model based on Fick`s law and the shrinking core model cannot describe the sorption process. On the contrary, the kinetic data were well fit by the Elovich equation. The apparent activation energies evaluated (3.5--8.4 kcal/mol at pH 3) indicated the combined film and particle diffusion mechanism.

  8. On the reaction of iron oxides and oxyhydroxides with tannic and phosphoric acid and their mixtures

    NASA Astrophysics Data System (ADS)

    Beltrán, J. J.; Novegil, F. J.; García, K. E.; Barrero, C. A.

    2010-01-01

    The actions of tannic acid, phosphoric acid and their mixture on lepidocrocite, goethite, superparamagnetic goethite, akaganeite, magnetite, hematite and maghemite for 1 day and 1 month were explored. It was found that these acids form iron tannates and phosphates. Lepidocrocite and magnetite were the iron phases more easily transformed with the mixture of the acids after 1 month of reaction, whereas hematite was the most resistant phase. In the case of goethite, our results suggest that in order to understand properly the action of these acids, we have to take into account its stoichiometry, surface area and degree of crystallinity.

  9. Dynamical Approach to Multiequilibria Problems for Mixtures of Acids and Their Conjugated Bases

    ERIC Educational Resources Information Center

    Glaser, Rainer E.; Delarosa, Marco A.; Salau, Ahmed Olasunkanmi; Chicone, Carmen

    2014-01-01

    Mathematical methods are described for the determination of steady-state concentrations of all species in multiequilibria systems consisting of several acids and their conjugated bases in aqueous solutions. The main example consists of a mixture of a diprotic acid H[subscript 2]A, a monoprotic acid HB, and their conjugate bases. The reaction…

  10. Lubrication from mixture of boric acid with oils and greases

    SciTech Connect

    Erdemir, A.

    1995-07-11

    Lubricating compositions are disclosed including crystalline boric acid and a base lubricant selected from oils, greases and the like. The lubricity of conventional oils and greases can also be improved by adding concentrates of boric acid.

  11. Lubrication from mixture of boric acid with oils and greases

    SciTech Connect

    Erdemir, Ali

    1995-01-01

    Lubricating compositions including crystalline boric acid and a base lubricant selected from oils, greases and the like. The lubricity of conventional oils and greases can also be improved by adding concentrates of boric acid.

  12. Separation of polyamines, conjugated to DNA, by reversed-phase high-performance liquid chromatography.

    PubMed

    Mateos, J L; Reyes, A; Vicente, C; Legaz, M E

    2000-02-18

    Genomic DNA was isolated from the lichen Evernia prunastri in order to analyze by high-performance liquid chromatography the occurrence of polyamines conjugated to the macromolecule. The acid-insoluble (PH) fraction of this DNA contained mainly conjugated spermidine, although small amounts of free putrescine and spermidine were also present. The PH fraction of DNA also contained conjugated evernic acid, the main phenol produced by this lichen species. Conjugation of polyamines to calf thymus DNA was carried out under in vitro conditions. Conjugation was to spermidine and mainly to spermine and produced DNA compactation. Evernic acid enhanced the action of polyamines in order to produce DNA aggregation.

  13. Polysulfone affinity membranes for the treatment of amino acid mixtures.

    PubMed

    Rodemann, K; Staude, E

    1995-06-20

    Affinity membranes for the treatment of solutions containing amino acids were obtained via lithiating polysulfone that was subsequently converted with glycidylether. From this polymer asymmetric ultrafiltration membranes were cast. The membranes were reacted with iminodiacetic acid yielding membranes fitted out with bidentate chelates. The same reaction path was applied to commercially available symmetric microfiltration membranes. The chelate-bearing membranes were complexed with Cu, Ni, and Zn ions. For the experiments with amino acids only the Cu-complexed membranes were used. The complexation constants for histidine and tryptophan for six different membranes were determined. Because of the affinity of these two amino acids for the complexed Cu ions, they could easily be separated from solutions containing amino acids such as alanine, glycine, and valine. Also, concentrating very dilute amino acid solutions was carried out successfully.

  14. Batch salicylic acid nitration by nitric acid/acetic acid mixture under isothermal, isoperibolic and adiabatic conditions.

    PubMed

    Andreozzi, R; Canterino, M; Caprio, V; Di Somma, I; Sanchirico, R

    2006-12-01

    Runaway phenomena and thermal explosions can originate during the nitration of salicylic acid by means of a nitric acid/acetic acid mixture when the thermal control is lost, mainly as a result of the formation and thermal decomposition of picric acid. The prediction of the behaviour of this system is thus of great importance in view of possible industrial applications and the need to avoid the occurrence of unwanted dangerous events. During a previous investigation a model was developed to simulate its behaviour when the starting concentration of the substrate is too low, thus, preventing the precipitation of poor soluble intermediates. In this work this model is extended to deal with more concentrated systems even in case of a solid phase separating during the process. To this purpose the previously assessed dependence of the solubility of 3-nitro and 5-nitrosalicylic acids upon temperature and nitric acid concentration is included in the model. It is assumed that when 3-nitro and 5-nitrosalicylic acids are partially suspended in the reacting medium a kinetic regime of "dissolution with reaction" is established; that is, the redissolution of these species is a fast process compared to the successive nitration to give dinitroderivatives. Good results are obtained in the comparison of the experimental data with those calculated both in isoperibolic and adiabatic conditions when the revised model is used.

  15. Polyamine Metabolism Changes in Psoriasis

    PubMed Central

    Broshtilova, Valentina; Lozanov, Valentina; Miteva, Ljubka

    2013-01-01

    Introduction: Polyamines – putrescine, spermidine and spermine are polycationic compounds ubiquitous for all living organisms. They are essential for the cell growth and differentiation, the control of cell cycle progress, apoptosis, and cancerogenesis. Accumulated scientific evidence suggests the central role of polyamines in the process of keratinocytic proliferation, differentiation, and regulation. Objective: To elucidate the polyamine metabolic changes that occur in benign keratinocytic proliferation. Fifty eight patients were enrolled in the study, 31 with plaque-form of psoriasis vulgaris, which had been referred to as a model of benign keratinocytic proliferation, and 27-healthy controls. Materials and Methods: An original, innovative chromatographic method was used to detect the levels of putrescine, spermidine, and spermine in all skin samples. Results: Were significantly proven (P < 0.05). No difference was found between the polyamines levels of non-lesional psoriatic skin and healthy controls. Psoriatic lesions showed a two-time higher concentration of all polyamines in lesional, compared to non-lesional skin. Spermine had the highest concentration and highest proliferation trend, which demonstrated the importance of propylamine synthesis in the pathogenesis of psoriasis. Spermine highest concentrations suggested the leading role of adenosine methionine decarboxylase (AMDC) in the pathogenesis of benign keratinocytic proliferations. Conclusions: Non-lesional skin in psoriatic patients did not show latent changes in polyamine metabolism. Psoriatic lesions demontrated two-time higher levels of the most essential biogenic polyamines compared to healthy controls. The highest level of spermine proved the crucial role of AMDC in the polyamine metabolism changes in psoriasis. Future therapeutic approaches should be focused on reduction of exogenic spermine intake, utilizing new spermine blockers, and synthesis of AMDC inhibitors. PMID:23919004

  16. Acid Base Titrations in Nonaqueous Solvents and Solvent Mixtures

    NASA Astrophysics Data System (ADS)

    Barcza, Lajos; Buvári-Barcza, Ágnes

    2003-07-01

    The acid base determination of different substances by nonaqueous titrations is highly preferred in pharmaceutical analyses since the method is quantitative, exact, and reproducible. The modern interpretation of the reactions in nonaqueous solvents started in the last century, but several inconsistencies and unsolved problems can be found in the literature. The acid base theories of Brønsted Lowry and Lewis as well as the so-called solvent theory are outlined first, then the promoting (and leveling) and the differentiating effects are discussed on the basis of the hydrogen-bond concept. Emphasis is put on the properties of formic acid and acetic anhydride since their importance is increasing.

  17. Modulation of protein synthesis by polyamines.

    PubMed

    Igarashi, Kazuei; Kashiwagi, Keiko

    2015-03-01

    Polyamines are ubiquitous small basic molecules that play important roles in cell growth and viability. Since polyamines mainly exist as a polyamine-RNA complex, we looked for proteins whose synthesis is preferentially stimulated by polyamines at the level of translation, and thus far identified 17 proteins in Escherichia coli and 6 proteins in eukaryotes. The mechanisms of polyamine stimulation of synthesis of these proteins were investigated. In addition, the role of eIF5A, containing hypusine formed from spermidine, on protein synthesis is described. These results clearly indicate that polyamines and eIF5A contribute to cell growth and viability through modulation of protein synthesis.

  18. Process monitored spectrophotometric titration coupled with chemometrics for simultaneous determination of mixtures of weak acids.

    PubMed

    Liao, Lifu; Yang, Jing; Yuan, Jintao

    2007-05-15

    A new spectrophotometric titration method coupled with chemometrics for the simultaneous determination of mixtures of weak acids has been developed. In this method, the titrant is a mixture of sodium hydroxide and an acid-base indicator, and the indicator is used to monitor the titration process. In a process of titration, both the added volume of titrant and the solution acidity at each titration point can be obtained simultaneously from an absorption spectrum by least square algorithm, and then the concentration of each component in the mixture can be obtained from the titration curves by principal component regression. The method only needs the information of absorbance spectra to obtain the analytical results, and is free of volumetric measurements. The analyses are independent of titration end point and do not need the accurate values of dissociation constants of the indicator and the acids. The method has been applied to the simultaneous determination of the mixtures of benzoic acid and salicylic acid, and the mixtures of phenol, o-chlorophenol and p-chlorophenol with satisfactory results.

  19. Denatured mammalian protein mixtures exhibit unusually high solubility in nucleic acid-free pure water.

    PubMed

    Futami, Junichiro; Fujiyama, Haruna; Kinoshita, Rie; Nonomura, Hidenori; Honjo, Tomoko; Tada, Hiroko; Matsushita, Hirokazu; Abe, Yoshito; Kakimi, Kazuhiro

    2014-01-01

    Preventing protein aggregation is a major goal of biotechnology. Since protein aggregates are mainly comprised of unfolded proteins, protecting against denaturation is likely to assist solubility in an aqueous medium. Contrary to this concept, we found denatured total cellular protein mixture from mammalian cell kept high solubility in pure water when the mixture was nucleic acids free. The lysates were prepared from total cellular protein pellet extracted by using guanidinium thiocyanate-phenol-chloroform mixture of TRIzol, denatured and reduced total protein mixtures remained soluble after extensive dialysis against pure water. The total cell protein lysates contained fully disordered proteins that readily formed large aggregates upon contact with nucleic acids or salts. These findings suggested that the highly flexible mixtures of disordered proteins, which have fully ionized side chains, are protected against aggregation. Interestingly, this unusual solubility is characteristic of protein mixtures from higher eukaryotes, whereas most prokaryotic protein mixtures were aggregated under identical conditions. This unusual solubility of unfolded protein mixtures could have implications for the study of intrinsically disordered proteins in a variety of cells.

  20. Polyamine conjugates of stigmasterol.

    PubMed

    Vida, Norbert; Svobodová, Hana; Rárová, Lucie; Drašar, Pavel; Saman, David; Cvačka, Josef; Wimmer, Zdeněk

    2012-10-01

    Three new polyamine conjugates with stigmasterol [(3β,22E)-stigmasta-5,22-dien-3-ol] were synthesized and subjected to basic antimicrobial and cytotoxic tests. The conjugate derived from spermine, (3β,22E)-stigmasta-5,22-dien-3-yl 4(12-amino-4,9-diaza-dodecylamino)-4-oxobutanoate (5c), displayed considerable antimicrobial activity on Staphylococcus aureus at low concentration (50 μg mL(-1)). The cytotoxic activity was tested on cells of human T-lymfoblastic leukemia (IC(50)=35.8 ± 10.3 μM (5c) and IC(50)=35.9 ± 5.7 μM (5b)) and normal human fibroblasts (IC(50)=38.0 ± 2.8 μM (5c) and IC(50)=45.5 ± 1.9 μM (5b)). Conjugate 5a displayed no activity in both tests.

  1. AMELIORATION OF ACID MINE DRAINAGE USING REACTIVE MIXTURES IN PERMEABLE REACTIVE BARRIERS

    EPA Science Inventory

    The generation and release of acidic drainage from mine wastes is an environmental problem of international scale. The use of zero-valent iron and/or iron mixtures in subsurface Permeable Reactive Barriers (PRB) presents a possible passive alternative for remediating acidic grou...

  2. Analysis of Steam Heating of a Two-Layer TBP/N-Paraffin/Nitric Acid Mixtures

    SciTech Connect

    Laurinat, J.E.; Hassan, N.M.; Rudisill, T.S.; Askew, N.M.

    1998-07-22

    This report presents an analysis of steam heating of a two-layer tri-n-butyl phosphate (TBP)/n-paraffin-nitric acid mixture.The purpose of this study is to determine if the degree of mixing provided by the steam jet or by bubbles generated by the TBP/nitric acid reaction is sufficient to prevent a runaway reaction.

  3. Dispersion of single-walled carbon nanotubes in alcohol-cholic acid mixtures

    NASA Astrophysics Data System (ADS)

    Dyshin, A. A.; Eliseeva, O. V.; Bondarenko, G. V.; Kolker, A. M.; Zakharov, A. G.; Fedorov, M. V.; Kiselev, M. G.

    2013-12-01

    A procedure for dispersing single-walled carbon nanotubes (SWNTs) for the preparation of suspensions with high concentrations of individual nanotubes in various solvents was described. The most stable suspensions were obtained from a mixture of ethanol with cholic acid at an acid concentration of 0.018 mol/kg.

  4. Identification of glycinin in vivo as a polyamine-conjugated protein via a gamma-glutamyl linkage.

    PubMed Central

    Kang, H; Lee, S G; Cho, Y D

    1998-01-01

    To identify a polyamine-conjugated protein by the action of transglutaminase in the absence of radiolabelled polyamine, extracts prepared from the leaves and developing soybean seeds were investigated for the specific activity of transglutaminase and the content of free polyamines. We identified the major storage protein, glycinin, as a polyamine-conjugated protein. This was established by the following procedures: (1) immunolocalization with antibody against putrescine prepared in rabbit against putrescine-BSA conjugate; (2) immunocross-reactivity on nitrocellulose transblot of the purified glycinin subunits by using antibody against putrescine; (3) identification of polyamines in acid hydrolysates of purified glycinin; (4) release of polyamines in proteolytic digests through the catalytic action of gamma-glutamylamine cyclotransferase, an enzyme specific for the disassembly of gamma-glutamylamines. The activity of gamma-glutamylamine cyclotransferase was also identified in soybean seeds. PMID:9601076

  5. Studies of single aerosol particles containing malonic acid, glutaric acid, and their mixtures with sodium chloride. I. Hygroscopic growth.

    PubMed

    Pope, Francis D; Dennis-Smither, Ben J; Griffiths, Paul T; Clegg, Simon L; Cox, R Anthony

    2010-04-29

    We describe a newly constructed electrodynamic balance with which to measure the relative mass of single aerosol particles at varying relative humidity. Measurements of changing mass with respect to the relative humidity allow mass (m) growth factors (m(aqueous)/m(dry)) and diameter (d) growth factors (d(aqueous)/d(dry)) of the aerosol to be determined. Four aerosol types were investigated: malonic acid, glutaric acid, mixtures of malonic acid and sodium chloride, and mixtures of glutaric acid and sodium chloride. The mass growth factors of the malonic acid and glutaric acid aqueous phase aerosols, at 85% relative humidity, were 2.11 +/- 0.08 and 1.73 +/- 0.19, respectively. The mass growth factors of the mixed organic/inorganic aerosols are dependent upon the molar fraction of the individual components. Results are compared with previous laboratory determinations and theoretical predictions.

  6. Dissociation of equimolar mixtures of aqueous carboxylic acids in ionic liquids: role of specific interactions.

    PubMed

    Shukla, Shashi Kant; Kumar, Anil

    2015-04-30

    Hammett acidity function observes the effect of protonation/deprotonation on the optical density/absorbance of spectrophotometric indicator. In this work, the Hammett acidity, H0, of equimolar mixtures of aqueous HCOOH, CH3COOH, and CH3CH2COOH was measured in 1-methylimidazolium-, 1-methylpyrrolidinium-, and 1-methylpiperidinium-based protic ionic liquids (PILs) and 1-butyl-3-methylimidazolium-based aprotic ionic liquid (AIL) with formate (HCOO(-)) anion. Higher H0 values were observed for the equimolar mixtures of aqueous carboxylic acids in protic ionic liquids compared with those of the aprotic ionic liquid because of the involvement of the stronger specific interactions between the conjugate acid of ionic liquid and conjugate base of carboxylic acids as suggested by the hard-soft acid base (HSAB) theory. The different H0 values for the equimolar mixtures of aqueous carboxylic acids in protic and aprotic ionic liquids were noted to depend on the activation energy of proton transfer (Ea,H(+)). The higher activation energy of proton transfer was obtained in AIL, indicating lower ability to form specific interactions with solute than that of PILs. Thermodynamic parameters determined by the "indicator overlapping method" further confirmed the involvement of the secondary interactions in the dissociation of carboxylic acids. On the basis of the thermodynamic parameter values, the potential of different ionic liquids in the dissociation of carboxylic acids was observed to depend on the hydrogen bond donor acidity (α) and hydrogen bond acceptor basicity (β), characteristics of specific interactions.

  7. Linear titration plots for the analysis of mixtures of three weak acids or bases.

    PubMed

    Midgley, D; McCallum, C

    1984-06-01

    Linearly related functions have been derived which enable mixtures of three weak acids or bases in solution to be analysed by means of pH-titration data. This theory has been tested with data from the titration of a variety of mixtures of acids. The data required for the functions are pH, volume of titrant, the equilibrium constants relevant to the mixture, and an independently determined equivalence volume. This may be the equivalence volume for one of the components of the mixture or the sum of the equivalence volumes for any two or all three of the components. It is immaterial how this equivalence volume is obtained, but it is usually possible to obtain the total equivalence volume from data in another part of the same titration curve (when a large excess of titrant has been added).

  8. Calculations of phase equilibria for mixtures of triglycerides, fatty acids, and their esters in lower alcohols

    NASA Astrophysics Data System (ADS)

    Stepanov, D. A.; Ermakova, A.; Anikeev, V. I.

    2011-01-01

    The objects of study were mixtures containing triglycerides and lower alcohols and also the products of the transesterification of triglycerides, glycerol and fatty acid esters. The Redlich-Kwong-Soave equation of state was used as a thermodynamic model for the phase state of the selected mixtures over wide temperature, pressure, and composition ranges. Group methods were applied to determine the critical parameters of pure substances and their acentric factors. The parameters obtained were used to calculate the phase diagrams and critical parameters of mixtures containing triglycerides and lower alcohols and the products of the transesterification of triglycerides, glycerol and fatty acid esters, at various alcohol/oil ratios. The conditions of triglyceride transesterification in various lower alcohols providing the supercritical state of reaction mixtures were selected.

  9. The coagulation characteristics of humic acid by using acid-soluble chitosan, water-soluble chitosan, and chitosan coagulant mixtures.

    PubMed

    Chen, Chih-Yu; Wu, Chung-Yu; Chung, Ying-Chien

    2015-01-01

    Chitosan is a potential substitute for traditional aluminium salts in water treatment systems. This study compared the characteristics of humic acid (HA) removal by using acid-soluble chitosan, water-soluble chitosan, and coagulant mixtures of chitosan with aluminium sulphate (alum) or polyaluminium chloride (PACl). In addition, we evaluated their respective coagulation efficiencies at various coagulant concentrations, pH values, turbidities, and hardness levels. Furthermore, we determined the size and settling velocity of flocs formed by these coagulants to identify the major factors affecting HA coagulation. The coagulation efficiency of acid- and water-soluble chitosan for 15 mg/l of HA was 74.4% and 87.5%, respectively. The optimal coagulation range of water-soluble chitosan (9-20 mg/l) was broader than that of acid-soluble chitosan (4-8 mg/l). Notably, acid-soluble chitosan/PACl and water-soluble chitosan/alum coagulant mixtures exhibited a higher coagulation efficiency for HA than for PACl or alum alone. Furthermore, these coagulant mixtures yielded an acceptable floc settling velocity and savings in both installation and operational expenses. Based on these results, we confidently assert that coagulant mixtures with a 1:1 mass ratio of acid-soluble chitosan/PACl and water-soluble chitosan/alum provide a substantially more cost-effective alternative to using chitosan alone for removing HA from water.

  10. Thermal Characterization of Lauric-Stearic Acid/Expanded Graphite Eutectic Mixture as Phase Change Materials.

    PubMed

    Zhu, Hua; Zhang, Peng; Meng, Zhaonan; Li, Ming

    2015-04-01

    The eutectic mixture of lauric acid (LA) and stearic acid (SA) is a desirable phase change material (PCM) due to the constant melting temperature and large latent heat. However, its poor thermal conductivity has hampered its broad utilization. In the present study, pure LA, SA and the mixtures with various mass fractions of LA-SA were used as the basic PCMs, and 10 wt% expanded graphite (EG) was added to enhance the thermal conductivities. The phase change behaviors, microstructural analysis, thermal conductivities and thermal stabilities of the mixtures of PCMs were investigated by differential scanning calorimetry (DSC), scanning electronic microscope (SEM), transient plane source (TPS) and thermogravimetric analysis (TGA), respectively. The results show that the LA-SA binary mixture of mixture ratio of 76.3 wt%: 23.7 wt% forms an eutectic mixture, which melts at 38.99 °C and has a latent heat of 159.94 J/g. The melted fatty acids are well absorbed by the porous network of EG and they have a good thermal stability. Furthermore, poor thermal conductivities can be well enhanced by the addition of EG.

  11. Lubricating oil compositions containing hydroxy polyether polyamines

    SciTech Connect

    Campbell, C.B.

    1987-09-29

    This patent describes a hydroxy polyether amine or polyamine additive, and a lubricating oil composition containing a major amount of oil of lubricating viscosity and from about 0.01 to about 10 weight percent of the additive. The additives consist of certain lubricating oil soluble hydroxy polyoxyalkylene polyamines. The compositions may be either mono or polyamines, but polyamines are preferred. The additive compounds have molecular weights of from about 500 to 2000, and preferably from about 700 to 1200.

  12. Serum amino acid concentrations in patients receiving total parenteral nutrition with an amino acid plus dextrose mixture.

    PubMed

    Philcox, J C; Hartley, T F; Worthley, L I; Thomas, D W

    1984-01-01

    The results of monitoring the serum amino acid concentrations during three infusion regimens using a 5:4 mixture of 70% glucose and the synthetic L-amino acid solution, Synthamin 17 (Travasol) are reported. Twelve stabilized patients received continuous total parenteral nutrition (TPN), eight of whom were subsequently placed on a second regimen of cyclical feeding. A separate group of five patients was infused with amino acids, both with and without simultaneous glucose. The serum amino acid concentrations indicated that the supply of valine, leucine, isoleucine, lysine, and histidine, and the synthesis of taurine from the infused methionine was suboptimal, particularly if the period of TPN was prolonged. The synthesis of tyrosine from phenylalanine appeared to be inversely proportional to the infusion rate of the TPN mixture, in particular the glucose component, resulting in depressed tyrosine and increased phenylalanine concentrations in serum during continuous iv nutrition. Cyclical infusions, on the other hand, permitted the tyrosine and phenylalanine concentrations to return to normal during the noninfusion stage of the cycle. Amino acid measurements enabled us to design an amino acids additive mixture which normalized the serum concentrations in three long-term home parenteral nutrition patients. As a result of these investigations serum amino acid measurements are used routinely to monitor the efficacy of TPN and accommodate any specific amino acid requirements of individual patients.

  13. An amino acid mixture improves glucose tolerance and lowers insulin resistance in the obese Zucker rat.

    PubMed

    Bernard, Jeffrey R; Liao, Yi-Hung; Ding, Zhenping; Hara, Daisuke; Kleinert, Maximilian; Nelson, Jeffrey L; Ivy, John L

    2013-07-01

    The purpose of this investigation was to test an amino acid mixture on glucose tolerance in obese Zucker rats [experiment (Exp)-1] and determine whether differences in blood glucose were associated with alterations in muscle glucose uptake [experiment (Exp)-2]. Exp-1 rats were gavaged with either carbohydrate (OB-CHO), carbohydrate plus amino acid mixture (OB-AA-1), carbohydrate plus amino acid mixture with increased leucine concentration (OB-AA-2) or water (OB-PLA). The glucose response in OB-AA-1 and OB-AA-2 were similar, and both were lower compared to OB-CHO. This effect of the amino acid mixtures did not appear to be solely attributable to an increase in plasma insulin. Rats in Exp-2 were gavaged with carbohydrate (OB-CHO), carbohydrate plus amino acid mixture (OB-AA-1) or water (OB-PLA). Lean Zuckers were gavaged with carbohydrate (LN-CHO). Fifteen minutes after gavage, a radiolabeled glucose analog was infused through a catheter previously implanted in the right jugular vein. Blood glucose was significantly lower in OB-AA-1 compared to OB-CHO while the insulin responses were similar. Glucose uptake was greater in OB-AA-1 compared with OB-CHO, and similar to that in LN-CHO in red gastrocnemius muscle (5.15 ± 0.29, 3.8 ± 0.27, 5.18 ± 0.34 µmol/100 g/min, respectively). Western blot analysis showed that Akt substrate of 160 kDa (AS160) phosphorylation was enhanced for OB-AA-1 and LN-CHO compared to OB-CHO. These findings suggest that an amino acid mixture improves glucose tolerance in an insulin resistant model and that these improvements are associated with an increase in skeletal muscle glucose uptake possibly due to improved intracellular signaling.

  14. Toxicokinetics and Oral Bioavailability of Halogenated Acetic Acids Mixtures in Naive and GSTzeta-Depleted Rats

    SciTech Connect

    Saghir, Shakil A.; Schultz, Irv R.

    2005-04-01

    Pharmacokinetics of halogenated acetic acid (HAA) mixtures in native and GSTzeta depleted rats was investigated. Rats were administered orally or i.v. to Mixture-1 (monobromo- dichloro-, chlorodibromo-, tribromo- acetic acids) or Mixture-2 (bromochloro-, dibromo-, trichloro- bromodichloro- acetic acids) at a dose of 25 ?mol/kg HAA and blood samples collected up to 36 h. GSTzeta depleted rats were also orally dosed with each mixture and euthanized at 0.25, 0.5, 1, 2 and 4 h to determine tissue distribution. In Mixture-1, GSTzeta depletion only affected the pharmacokinetics of DCAA, which increased the elimination t? from 9 min to 1.3 h. After oral administration, DCAA exhibited a complex time-course plasma profile with secondary peaks appearing long after completion of the initial absorption phase. This phenomenon coincided with elevated DCA levels in the lower portion of the GI tract compared to CDBAA and TBAA. For Mixture-2, all di-HAAs were eliminated extremely rapidly from plasma in both na?ve and GSTzeta depleted animals (t? was 4-11 min in na?ve and 11-24 min in GSTzeta depleted rats), t? of BDCAA and TCAA was 3.5 and 12 h in na?ve and 2.3 and 7.5 h in GSTzeta depleted rats. The primary difference in the pharmacokinetics among HAAs when administered as mixture was the total body clearance (Clb) which was reduced compared to after individual administration. These results suggest competitive interactions between tri- and di-HAAs beyond what would be predicted from individual HAA studies. For di-HAAs, the total dose is important as clearance is dose dependent due to competition for GSTzeta. When considering HAAs dosimetry, importance should be placed on both the components of the mixture and prior exposure history to di-HAAs.

  15. Analysis of naphthenic acid mixtures as pentafluorobenzyl derivatives by gas chromatography-electron impact mass spectrometry.

    PubMed

    Gutierrez-Villagomez, Juan Manuel; Vázquez-Martínez, Juan; Ramírez-Chávez, Enrique; Molina-Torres, Jorge; Trudeau, Vance L

    2017-01-01

    In this study, we report for the first time the efficiency of pentafluorobenzyl bromide (PFBBr) for naphthenic acid (NA) mixtures derivatization, and the comparison in the optimal conditions to the most common NAs derivatization reagents, BF3/MeOH and N-(t-butyldimethylsilyl)-N-methyltrifluoroacetamide (MTBSTFA). Naphthenic acids are carboxylic acid mixtures of petrochemical origin. These compounds are important for the oil industry because of their corrosive properties, which can damage oil distillation infrastructure. Moreover, NAs are commercially used in a wide range of products such as paint and ink driers, wood and fabric preservatives, fuel additives, emulsifiers, and surfactants. Naphthenic acids have also been found in sediments after major oils spills in the United States and South Korea. Furthermore, the toxicity of the oil sands process-affected water (OSPW), product of the oil sands extraction activities in Canada's oil sands, has largely been attributed to NAs. One of the main challenges for the chromatographic analysis of these mixtures is the resolution of the components. The derivatization optimization was achieved using surface response analysis with molar ratio and time as factors for derivatization signal yield. After gas chromatography-electron impact mass spectrometry (GC/EIMS) analysis of a mixture of NA standards, it was found that the signal produced by PFB-derivatives was 2.3 and 1.4 times higher than the signal produced by methylated and MTBS-derivatives, respectively. The pentafluorobenzyl derivatives have a characteristic fragment ion at 181m/z that is diagnostic for the differentiation of carboxylic and non-carboxylic acid components within mixtures. In the analysis of a Sigma and a Merichem derivatized oil extract NA mixtures, it was found that some peaks lack the characteristic fragment ion; therefore they are not carboxylic acids. Open column chromatography was used to obtain a hexane and a methanol fraction of the Sigma and

  16. Modification of wheat starch with succinic acid/acetanhydride and azelaic acid/acetanhydride mixtures. II. Chemical and physical properties.

    PubMed

    Ačkar, Durđica; Subarić, Drago; Babić, Jurislav; Miličević, Borislav; Jozinović, Antun

    2014-08-01

    The aim of this research was to investigate the influence of modification with succinic acid/acetanhydride and azelaic acid/acetanhydride mixtures on chemical and physical properties of wheat starch. Starch was isolated from two wheat varieties and modified with mixtures of succinic acid and acetanhydride and azelaic acid and acetanhydride in 4, 6 and 8% (w/w). Total starch content, resistant starch content, degree of modification, changes in FT-IR spectra, colour, gel texture and freeze-thaw stability were determined. Results showed that resistant starch content increased by both investigated modifications, and degree of modification increased proportionally to amount of reagents used. FT-IR analysis of modified starches showed peak around 1,740 cm(-1), characteristic for carbonyl group of ester. Total colour difference caused by modifications was detectable by trained people. Adhesiveness significantly increased, while freeze-thaw stability decreased by both investigated modifications.

  17. Probing the acidity of carboxylic acids in protic ionic liquids, water, and their binary mixtures: activation energy of proton transfer.

    PubMed

    Shukla, Shashi Kant; Kumar, Anil

    2013-02-28

    Acidity functions were used to express the ability of a solvent/solution to donate/accept a proton to a solute. The present work accounts for the acidity determination of HCOOH, CH3COOH, and CH3CH2COOH in the alkylimidazolium-based protic ionic liquids (PILs), incorporated with carboxylate anion, water, and in a binary mixture of PIL and water using the Hammett acidity function, H0. A reversal in the acidity trend was observed, when organic acids were transferred from water to PIL. It was emphasized that an increased stabilization offered by PIL cation toward the more basic conjugate anion of organic acid was responsible for this anomalous change in acidity order in PILs, which was absent in water. The greater stabilization of a basic organic anion by PIL cation is discussed in terms of the stable hard–soft acid base (HSAB) pairing. A change in the H0 values of these acids was observed with a change in temperature, and a linear correlation between the ln H0 and 1/T was noted. This relationship points toward the activation energy of proton transfer (E(a,H+)), a barrier provided by the medium during the proton transfer from Brønsted acid to indicator. The H0 function in binary mixtures points to the involvement of pseudosolvent, the behavior of which changes with the nature and concentration of acid. The presence of the maxima/minima in the H0 function is discussed in terms of the synergetic behavior of the pseudosolvent composed of the mixtures of aqueous PILs.

  18. Structure of Prokaryotic Polyamine Deacetylase Reveals Evolutionary Functional Relationships with Eukaryotic Histone Deacetylases

    PubMed Central

    Lombardi, Patrick M.; Angell, Heather D.; Whittington, Douglas A.; Flynn, Erin F.; Rajashankar, Kanagalaghatta R.; Christianson, David W.

    2011-01-01

    Polyamines are a ubiquitous class of polycationic small molecules that can influence gene expression by binding to nucleic acids. Reversible polyamine acetylation regulates nucleic acid binding and is required for normal cell cycle progression and proliferation. Here, we report the structures of Mycoplana ramosa acetylpolyamine amidohydrolase (APAH) complexed with a transition state analogue and a hydroxamate inhibitor, and an inactive mutant complexed with two acetylpolyamine substrates. The structure of APAH is the first of a histone deacetylase-like oligomer and reveals that an 18-residue insert in the L2 loop promotes dimerization and the formation of an 18-Å long “L”-shaped active site tunnel at the dimer interface, accessible only to narrow and flexible substrates. The importance of dimerization for polyamine deacetylase function leads to the suggestion that a comparable dimeric or double-domain histone deacetylase could catalyze polyamine deacetylation reactions in eukaryotes. PMID:21268586

  19. Structure of Prokaryotic Polyamine Deacetylase Reveals Evolutionary Functional Relationships with Eukaryotic Histone Deacetylases

    SciTech Connect

    P Lombardi; H Angell; D Whittington; E Flynn; K Rajashankar; D Christianson

    2011-12-31

    Polyamines are a ubiquitous class of polycationic small molecules that can influence gene expression by binding to nucleic acids. Reversible polyamine acetylation regulates nucleic acid binding and is required for normal cell cycle progression and proliferation. Here, we report the structures of Mycoplana ramosa acetylpolyamine amidohydrolase (APAH) complexed with a transition state analogue and a hydroxamate inhibitor and an inactive mutant complexed with two acetylpolyamine substrates. The structure of APAH is the first of a histone deacetylase-like oligomer and reveals that an 18-residue insert in the L2 loop promotes dimerization and the formation of an 18 {angstrom} long 'L'-shaped active site tunnel at the dimer interface, accessible only to narrow and flexible substrates. The importance of dimerization for polyamine deacetylase function leads to the suggestion that a comparable dimeric or double-domain histone deacetylase could catalyze polyamine deacetylation reactions in eukaryotes.

  20. Universal nucleic acids sample preparation method for cells, spores and their mixture

    DOEpatents

    Bavykin, Sergei [Darien, IL

    2011-01-18

    The present invention relates to a method for extracting nucleic acids from biological samples. More specifically the invention relates to a universal method for extracting nucleic acids from unidentified biological samples. An advantage of the presently invented method is its ability to effectively and efficiently extract nucleic acids from a variety of different cell types including but not limited to prokaryotic or eukaryotic cells and/or recalcitrant organisms (i.e. spores). Unlike prior art methods which are focused on extracting nucleic acids from vegetative cell or spores, the present invention effectively extracts nucleic acids from spores, multiple cell types or mixtures thereof using a single method. Important that the invented method has demonstrated an ability to extract nucleic acids from spores and vegetative bacterial cells with similar levels effectiveness. The invented method employs a multi-step protocol which erodes the cell structure of the biological sample, isolates, labels, fragments nucleic acids and purifies labeled samples from the excess of dye.

  1. Effects of organic acid-surfactant mixtures on levels of bacteria and beef quality traits

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Introduction: Organic acid efficacy as an antimicrobial treatment of beef carcass surfaces may be increased through the addition of surfactants. However, the effects of antimicrobial-surfactant mixtures on beef quality traits such as flavor and color stability may make their use unacceptable. Purp...

  2. Testing for departures from additivity in mixtures of perfluoroalkyl acids (PFAAs)

    EPA Science Inventory

    This study is a follow-up to a paper by Carr, et al. that determined a design structure to optimally test for departures from additivity in a fixed ratio mixture of four perfluoroalkyl acids (PFAAs) using an in vitro transiently-transfected COS- 1 PPARa reporter model with an NHA...

  3. RNA, Proteins and Polyamines During Tube Growth in Germinating Apple Pollen 1

    PubMed Central

    Bagni, Nello; Adamo, Patrizia; Serafini-Fracassini, Donatella; Villanueva, Victor R.

    1981-01-01

    Variations of RNA, protein, and free- and trichloroacetic acid-soluble bound polyamine levels were determined during tube growth in germinating Malus domestica Borkh. cv. Starkrimson pollen. During rehydration of pollen no marked differences were observed, whereas, during germination, RNA, proteins, and polyamines showed parallel decreases. At the same time, there was synthesis of RNA and polyamines as indicated by use of labeled precursors. The data indicate that during germination: (a) the genes for rRNA, tRNA, and probably mRNA are active; (b) the enzymes involved in polyamine biosynthesis are very active. High levels of free arginine during the first 15 minutes were observed, probably in response to a demand for this precursor in polyamine biosynthesis. Moreover, profiles of the variations in the specific activities of RNA and polyamines showed similar patterns. The results indicate that biosynthesis of RNA and polyamines precedes tube emergence. The possible role of these compounds, which are known to be released into the medium in the progamic phase of the fertilization processes, is considered. PMID:16661988

  4. The inhibition of prions through blocking prion conversion by permanently charged branched polyamines of low cytotoxicity.

    PubMed

    Lim, Yong-beom; Mays, Charles E; Kim, Younghwan; Titlow, William B; Ryou, Chongsuk

    2010-03-01

    Branched polyamines are effective in inhibiting prions in a cationic surface charge density dependent manner. However, toxicity associated with branched polyamines, in general, often hampers the successful application of the compounds to treat prion diseases. Here, we report that constitutively maintained cationic properties in branched polyamines reduced the intrinsic toxicity of the compounds while retaining the anti-prion activities. In prion-infected neuroblastoma cells, quaternization of amines in polyethyleneimine (PEI) and polyamidoamine (PAMAM) dendrimers markedly increased the nontoxic concentration ranges of the compounds and still supported, albeit reduced, an appreciable level of anti-prion activity in clearing prions from the infected cells. Furthermore, quaternized PEI was able to degrade prions at acidic pH conditions and inhibit the in vitro prion propagation facilitated by conversion of the normal prion protein isoform to its misfolded counterpart, although such activities were decreased by quaternization. Quaternized PAMAM was least effective in degrading prions but efficiently inhibited prion conversion with the same efficacy as unmodified PAMAM. Our results suggest that quaternization represents an effective strategy for developing nontoxic branched polyamines with potent anti-prion activity. This study highlights the importance of polyamine structural control for developing polyamine-based anti-prion agents and understanding of an action mechanism of quaternized branched polyamines.

  5. Isolation of a gene encoding a putative polyamine transporter from Candida albicans, GPT1.

    PubMed

    McNemar, M D; Gorman, J A; Buckley, H R

    2001-04-01

    A gene encoding a transport protein from the pathogenic yeast, Candida albicans, has been isolated during a complementation experiment utilizing an ornithine decarboxylase-negative (spe1 Delta) strain of Saccharomyces cerevisiae. This gene restores gamma-aminobutyric acid (GABA) transport to a GABA transport-negative mutant of S. cerevisiae and encodes a protein which putatively allows transport of one or more of the polyamines. We have assigned the name GPT1 (GABA/polyamine transporter) to this gene.

  6. Characterization of a Polyamine Microsphere and Its Adsorption for Protein

    PubMed Central

    Wang, Feng; Liu, Pei; Nie, Tingting; Wei, Huixian; Cui, Zhenggang

    2013-01-01

    A novel polyamine microsphere, prepared from the water-in-oil emulsion of polyethylenimine, was characterized. The investigation of scanning electron microscopy showed that the polyamine microsphere is a regular ball with a smooth surface. The diameter distribution of the microsphere is 0.37–4.29 μm. The isoelectric point of the microsphere is 10.6. The microsphere can adsorb proteins through the co-effect of electrostatic and hydrophobic interactions. Among the proteins tested, the highest value of adsorption of microsphere, 127.8 mg·g−1 microsphere, was obtained with lipase. In comparison with other proteins, the hydrophobic force is more important in promoting the adsorption of lipase. The microsphere can preferentially adsorb lipase from an even mixture of proteins. The optimum temperature and pH for the selective adsorption of lipase by the microsphere was 35 °C and pH 7.0. PMID:23344018

  7. Free and conjugated polyamines and phenols in raw and alkaline-clarified sugarcane juices.

    PubMed

    de Armas, R; Martinez, M; Vicente, C; Legaz, M E

    1999-08-01

    Sugarcane juice contains a lot of sucrose associated with several monosaccharides, defined as low molecular mass carbohydrates (LMMC), as well as some polysaccharides and glycoproteins, which are defined as mid and high molecular mass carbohydrates (MMMC and HMMC, respectively). These three categories of carbohydrates can be separated by size-exclusion chromatography through Sephadex G-10 and Sephadex G-50 columns, but elution profiles change drastically after juice clarification performed by adjusting the pH value of the juice to 8.0. In addition, polyamines and some phenolics are currently associated with carbohydrate preparations, and the distribution pattern of these conjugates also changes after clarification. Polyamine levels generally decrease after juice clarification. Cadaverine is completely removed from the different carbohydrate preparations, whereas spermidine is the main polyamine occurring in association with sugarcane carbohydrates, as free or acid-soluble form in LMMC preparation or as acid-soluble and -insoluble forms in both MMMC and HMMC preparations. Polyamines, presumably spermidine, conjugate to p-hydroxybenzoic acid in LMMC, mostly to caffeic acid in MMMC, and to syringic acid in HMMC preparations. HMMC-associated polyamines appear in both acid-soluble and -insoluble fractions. Syringic acid also occurs in the LMMC preparation, but juice clarification changes it from acid-soluble to free form, and it coelutes with sucrose.

  8. Spectrofluorometric analysis of amino acid mixtures: Implications for future space missions

    NASA Astrophysics Data System (ADS)

    Chan, Hoi S.; Martins, Zita; Sephton, Mark A.

    2012-01-01

    Efficient detection of organic molecules is fundamental for the success of future life detection missions. Spectrofluorometric analysis is one of the many techniques that may be used to detect organic molecules in extraterrestrial settings. A particularly important class of organic molecules to target is the amino acids on which all terrestrial life depends. This study aims to identify the optimum fluorescence excitation and emission wavelengths for 17 amino acid standards to examine the effects of amino acid concentrations, mixtures and fluorescence quenching. The results and interpretations can guide the design and operation of life detection protocols on future space missions.

  9. Thermophysical Properties of Energetic Ionic Liquids/Nitric Acid Mixtures: Insights from Molecular Dynamics Simulations

    DTIC Science & Technology

    2013-01-01

    W L. Physical properties of concentrated nitric acid . UNT Digital Library. http://digital.library.unt.edu/ark:/67531/metadc56640/.) 23 M. Engelmann... Nitric Acid Mixtures: Insights from Molecular Dynamics Simulations 5a. CONTRACT NUMBER FA9300-11-C-3012 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER...Rev. 8-98) Prescribed by ANSI Std. 239.18 1     Thermophysical  Properties  of  Energetic  Ionic  Liquids/ Nitric   Acid

  10. Lipid mixtures containing a very high proportion of saturated fatty acids only modestly impair insulin signaling in cultured muscle cells.

    PubMed

    Newsom, Sean A; Everett, Allison C; Park, Sanghee; Van Pelt, Douglas W; Hinko, Alexander; Horowitz, Jeffrey F

    2015-01-01

    In vitro examinations of the effect of saturated fatty acids on skeletal muscle insulin action often use only one or two different fatty acid species, which does not resemble the human plasma fatty acid profile. We compared graded concentrations (0.1-0.8 mM) of 3 different lipid mixtures: 1) a physiologic fatty acid mixture (NORM; 40% saturated fatty acids), 2) a physiologic mixture high in saturated fatty acids (HSFA; 60% saturated fatty acids), and 3) 100% palmitate (PALM) on insulin signaling and fatty acid partitioning into triacylglycerol (TAG) and diacylglycerol (DAG) in cultured muscle cells. As expected, PALM readily impaired insulin-stimulated pAktThr308/Akt and markedly increased intracellular DAG content. In contrast, the fatty acid mixtures only modestly impaired insulin-stimulated pAktThr308M/Akt, and we found no differences between NORM and HSFA. Importantly, NORM and HSFA did not increase DAG content, but instead dose-dependently increased TAG accumulation. Therefore, the robust impairment in insulin signaling found with palmitate exposure was attenuated with physiologic mixtures of fatty acids, even with a very high proportion of saturated fatty acids. This may be explained in part by selective partitioning of fatty acids into neutral lipid (i.e., TAG) when muscle cells were exposed to physiologic lipid mixtures.

  11. Modulation of the NMDA receptor by polyamines

    SciTech Connect

    Williams, K.; Romano, C.; Dichter, M.A.; Molinoff, P.B. )

    1991-01-01

    Results of recent biochemical and electrophysiological studies have suggested that a recognition site for polyamines exists as part of the NMDA receptor complex. The endogenous polyamines spermine and spermidine increase the binding of open-channel blockers and increase NMDA-elicited currents in cultured neutrons. These polyamines have been termed agonists at the polyamine recognition site. Studies of the effects of natural and synthetic polyamines on the binding of ({sup 3}H)MK-801 and on NMDA-elicited currents in cultured neurons have led to the identification of compounds classified as partial agonists, antagonists, and inverse agonists at the polyamine recognition site. Polyamines have also been found to affect the binding of ligands to the recognition sites for glutamate and glycine. However, these effects may be mediated at a site distinct from that at which polyamines act to modulate the binding of open-channel blockers. Endogenous polyamines may modulate excitatory synaptic transmission by acting at the polyamine recognition site of the NMDA receptor. This site could represent a novel therapeutic target for the treatment of ischemia-induced neurotoxicity, epilepsy, and neurodegenerative diseases.

  12. Determination of component concentrations in mixtures of weak and strong acids and bases by linear algebraic methods.

    PubMed

    Ivaska, A; Nagypál, I

    1980-09-01

    A general expression for transforming potentiometric titration curves of mixtures of weak acids into a system of linear equations is derived. The solution of the linear equations gives directly the concentrations of the components. This linear transformation method is illustrated by the analysis of mixtures of weak acids with overlapping dissociation equilibria. The possible presence of a strong acid or strong base in the mixture can also be detected and its concentration simultaneously determined. The method can also be used for analysis of an ampholyte and solutions containing a weak acid and its conjugate base. For example a mixture of hydroxyacetic acid (pK approximately 3.6), acetic acid (pK approximately 4.6) and hydroxylamine hydrochloride (pK approximately 6) was analysed in the presence of strong acid with an average relative error of approximately 2%.

  13. Laboratory study on the hygroscopic behavior of external and internal C2-C4 dicarboxylic acid-NaCl mixtures.

    PubMed

    Ma, Qingxin; Ma, Jinzhu; Liu, Chang; Lai, Chengyue; He, Hong

    2013-09-17

    Atmospheric aerosol is usually found to be a mixture of various inorganic and organic components in field measurements, whereas the effect of this mixing state on the hygroscopicity of aerosol particles has remained unknown. In this study, the hygroscopic behavior of mixtures of C2-C4 dicarboxylic acids and NaCl was investigated. For both externally and internally mixed malonic acid-NaCl and succinic acid-NaCl particles, correlation between water content and chemical composition was observed and the water content of these mixtures at relative humidity (RH) above 80% can be well predicted by the Zdanovskii-Stokes-Robinson (ZSR) method. In contrast, a nonlinear relation between the total water content of the mixtures and the water content of each chemical composition separately was found for oxalic acid-NaCl mixtures. Compared to the values predicted by the ZSR method, the dissolution of oxalic acid in external mixtures resulted in an increase in the total water content, whereas the formation of less hygroscopic disodium oxalate in internal mixtures led to a significant decrease in the total water content. Furthermore, we found that the hygroscopicity of the sodium dicarboxylate plays a critical role in determining the aqueous chemistry of dicarboxylic acid-NaCl mixtures during the humidifying and dehumidifying process. It was also found that the hydration of oxalic acid and the deliquescence of NaCl did not change in external oxalic acid-NaCl mixtures. The deliquescence relative humidity (DRHs) for both malonic acid and NaCl decreased in both external and internal mixtures. These results could help in understanding the conversion processes of dicarboxylic acids to dicarboxylate salts, as well as the substitution of Cl by oxalate in the atmosphere. It was demonstrated that the effect of coexisting components on the hygroscopic behavior of mixed aerosols should not be neglected.

  14. Analysis of a mixture of a known and an unknown weak acid by titration to a preset pH.

    PubMed

    Livaska, A

    1975-12-01

    The preset-pH titration method has been used to indicate the presence of a second acid when the titration curve (pH vs. volume of added titrant) seems to indicate only one acid. By use of the method even small amounts of propionic acid can be detected in an acetic acid solution despite the small value of Delta log K(H)(HA) = 0.18. Binary mixtures of acids may bs analysed when one acid is known, and log k(H)(HA) for the unknown acid may be found. Acetic acid, as the known acid, has been determined together with hydrochloric, mandelic, hydroxyacetic or boric acid or ammonium ion, with an error of about 1%. The method can be used in some cases for titration of ternary mixtures of one known and two unknown acids. Only the sum of the unknown acids can then be determined together with the known acid.

  15. Understanding the synergistic effect of arginine and glutamic acid mixtures on protein solubility.

    PubMed

    Shukla, Diwakar; Trout, Bernhardt L

    2011-10-20

    Understanding protein solubility is a key part of physical chemistry. In particular, solution conditions can have a major effect, and the effect of multiple cosolutes is little understood. It has been shown that the simultaneous addition of L-arginine hydrochloride and L-glutamic acid enhances the maximum achievable solubility of several poorly soluble proteins up to 4-8 times (Golovanov et. al, J. Am. Chem. Soc., 2004, 126, 8933-8939) and reduces the intermolecular interactions between proteins. The observed solubility enhancement is negligible for arginine and glutamic acid solutions as compared to the equimolar mixtures. In this study, we have established the molecular mechanism behind this observed synergistic effect of arginine and glutamic acid mixtures using preferential interaction theory and molecular dynamics simulations of Drosophilia Su(dx) protein (ww34). It was found that the protein solubility enhancement is related to the relative increase in the number of arginine and glutamic acid molecules around the protein in the equimolar mixtures due to additional hydrogen bonding interactions between the excipients on the surface of the protein when both excipients are present. The presence of these additional molecules around the protein leads to enhanced crowding, which suppresses the protein association. These results highlight the role of additive-additive interaction in tuning the protein-protein interactions. Furthermore, this study reports a unique behavior of additive solutions, where the presence of one additive in solution affects the concentration of another on the protein surface.

  16. Reactive airways dysfunction syndrome in housewives due to a bleach-hydrochloric acid mixture.

    PubMed

    Gorguner, Metin; Aslan, Sahin; Inandi, Tacettin; Cakir, Zeynep

    2004-02-01

    The sudden onset of asthmalike symptoms and persistence of airway reactivity following an acute exposure to an irritant gas or vapor has been termed reactive airways dysfunction syndrome (RADS). A mixture of sodium hypochlorite (bleach, 40%) and hydrochloric acid (18%) is commonly used as a household cleaning solution in our region. From this mixture, chlorine gas is produced, which can cause airway damage and ensuing RADS. Here we describe findings of patients with RADS due to this cleaning mixture, and determine factors associated with a favorable outcome. Data were collected retrospectively on 55 symptomatic patients presenting to our emergency department after inhalation exposure to a mixture of bleach and hydrochloric acid. Symptoms, past medical and smoking history, details of the exposure, initial peak expiratory flow rate (PEFR) and oxygenation, and acute reversibility of airways obstruction were documented. All patients met previously defined criteria for the diagnosis of RADS, but did not undergo methacholine challenge testing and bronchoalveolar lavage or histopathologic study. Fifty patients were followed over the course of 3 mo. The majority of exposures (64%) occurred in the bathroom or kitchen. Only 21 of 55 (38%) patients showed an improvement in PEFR of 15% or greater following two beta(2)-agonist inhalation treatments. In follow-up, 48 patients (87%) improved clinically and functionally (FEV(1)). Seven patients (13%) deteriorated, with ARDS developing in two, one of whom died from respiratory failure. Advanced age, initial low PEFR, exposure in a small enclosed area, use immediately after mixing, and prolonged short- and long-term exposures were associated with a poorer prognosis. This descriptive study is the largest case series in the literature of RADS developing after exposure to a bleach-hydrochloric acid mixture. The optimum acute treatment and long-term outcomes for patients with RADS due to this combination still need to be determined.

  17. Polyamines: essential factors for growth and survival.

    PubMed

    Kusano, T; Berberich, T; Tateda, C; Takahashi, Y

    2008-08-01

    Polyamines are low molecular weight, aliphatic polycations found in the cells of all living organisms. Due to their positive charges, polyamines bind to macromolecules such as DNA, RNA, and proteins. They are involved in diverse processes, including regulation of gene expression, translation, cell proliferation, modulation of cell signalling, and membrane stabilization. They also modulate the activities of certain sets of ion channels. Because of these multifaceted functions, the homeostasis of polyamines is crucial and is ensured through regulation of biosynthesis, catabolism, and transport. Through isolation of the genes involved in plant polyamine biosynthesis and loss-of-function experiments on the corresponding genes, their essentiality for growth is reconfirmed. Polyamines are also involved in stress responses and diseases in plants, indicating their importance for plant survival. This review summarizes the recent advances in polyamine research in the field of plant science compared with the knowledge obtained in microorganisms and animal systems.

  18. Improvement of the analysis of dansylated derivatives of polyamines and their conjugates by high-performance liquid chromatography.

    PubMed

    Fontaniella, B; Mateos, J L; Vicente, C; Legaz, M E

    2001-06-15

    The paper described a method for improving the hydrolysis of conjugated polyamines in PH fraction, isolated from the lichen Evernia prunastri, as well as the optimization of dansylation procedure of these polyamines on the basis of the pH value to which derivatization is achieved. Dansylated polyamines have been later separated by high-performance liquid chromatography (HPLC) using a gradient elution. Hydrolysis of conjugates requires acid treatment at room temperature rather than at 110 degrees C, as usually described. Dansylation is improved at high pH values, whereas removal of phenolics (mainly evernic acid), from the conjugates requires low pH values.

  19. Preparation of polyimides from mixtures of monomeric diamines and esters of polycarboxylic acids

    NASA Technical Reports Server (NTRS)

    Serafini, T. T.; Delvigs, P.; Lightsey, G. R. (Inventor)

    1973-01-01

    Polyimides having high thermal and oxidative stability are prepared by the reaction of a mixture of monomers comprising (1) a dialkyl or tetraalkyl ester of an aromatic tetracarboxylic acid; (2) an aromatic diamine; and (3) a monoalkyl or dialkyl ester of a dicarboxylic acid where in the ratio of a:b:c is n:(n+1):2, wherein n has a value from 1 to 20. The mixture of monomers is prepared in a 30 to 70 percent by weight solution of an organic solvent, a substrate impregnated with the solution and heated at 50 to 205 C to remove said solvent and form a low molecular weight prepolymer, and thereafter heated at 275 to 350 C to cure to a high molecular weight polyimide.

  20. Enzymatic synthesis of cocoa butter equivalent from olive oil and palmitic-stearic fatty acid mixture.

    PubMed

    Mohamed, Ibrahim O

    2015-01-01

    The main goal of the present research is to restructure olive oil triacylglycerol (TAG) using enzymatic acidolysis reaction to produce structured lipids that is close to cocoa butter in terms of TAG structure and melting characteristics. Lipase-catalyzed acidolysis of refined olive oil with a mixture of palmitic-stearic acids at different substrate ratios was performed in an agitated batch reactor maintained at constant temperature and agitation speed. The reaction attained steady-state conversion in about 5 h with an overall conversion of 92.6 % for the olive oil major triacylglycerol 1-palmitoy-2,3-dioleoyl glycerol (POO). The five major TAGs of the structured lipids produced with substrate mass ratio of 1:3 (olive oil/palmitic-stearic fatty acid mixture) were close to that of the cocoa butter with melting temperature between 32.6 and 37.7 °C. The proposed kinetics model used fits the experimental data very well.

  1. Charge transport and structural dynamics in carboxylic-acid-based deep eutectic mixtures.

    PubMed

    Griffin, Philip J; Cosby, Tyler; Holt, Adam P; Benson, Roberto S; Sangoro, Joshua R

    2014-08-07

    Charge transport and structural dynamics in the 1:2 mol ratio mixture of lidocaine and decanoic acid (LID-DA), a model deep eutectic mixture (DEM), have been characterized over a wide temperature range using broad-band dielectric spectroscopy and depolarized dynamic light scattering. Additionally, Fourier transform infrared spectroscopy measurements were performed to assess the degree of proton transfer between the neutral parent molecules. From our detailed analysis of the dielectric spectra, we have determined that this carboxylic-acid-based DEM is approximately 25% ionic at room temperature. Furthermore, we have found that the characteristic diffusion rate of mobile charge carriers is practically identical to the rate of structural relaxation at all measured temperatures, indicating that fast proton transport does not occur in LID-DA. Our results demonstrate that while LID-DA exhibits the thermal characteristics of a DEM, its charge transport properties resemble those of a protic ionic liquid.

  2. Use of super acids to digest chrysotile and amosite asbestos in simple mixtures or matrices found in building materials compositions

    SciTech Connect

    Sugama, T.; Petrakis, L.; Webster, R.P.

    1999-12-21

    A composition for converting asbestos-containing material to environmentally benign components is provided. The composition comprises a fluoro acid decomposing agent which can be applied to either amosite-containing thermal insulation or chrysotile-containing fire-proof material or to any asbestos-containing material which includes of chrysotile and amosite asbestos. The fluoro acid decomposing agent includes FP{sub 0}(OH){sub 2}, hexafluorophosphoric acid, a mixture of hydrofluoric and phosphoric acid and a mixture of hexafluorophosphoric acid and phosphoric acid. A method for converting asbestos-containing material to environmentally benign components is also provided.

  3. Polyamines and polyamine biosynthesis in cells exposed to hyperthermia

    SciTech Connect

    Gerner, E.W.; Stickney, D.G.; Herman, T.S.; Fuller, D.J.

    1983-02-01

    The issue of how polyamines act to sensitize cultured cells to the lethal effects of hyperthermia was investigated using Chinese hamster cells which were induced to express thermotolerance. Intracellular levels of these naturally occurring polycations were manipulated in certain situations by treating whole cells with methylglyoxal bis-(guanylhydrazone), an inhibitor of the S-adenosyl-L-methionine decarboxylases. Exogenous spermine as low as 100 ..mu..M in the culture media dramatically sensitized cells expressing thermotolerance to the lethal effects of subsequent 42/sup 0/C exposures. When thermotolerance was differentially induced in cultures exposed to 42.4/sup 0/C by varying the rate of heating from 37 to 42.4/sup 0/C, the most resistant cells and the highest levels of intracellular spermidine and spermine. This finding was explainable in part by the observation that the putrescine-dependent S-adenosyl-L-methionine decarboxylase activity was minimally affected in cells expressng the greatest degree of thermotolerance. When this enzyme activity was inhibited by drug, lowered intracellular polyamine levels did not correspond with subsequent survival responses to heat. Interestingly, cultures treated with methylglyoxal bis-(guanylhydrazone) 24 hr previous to heat exposure showed a reduced capacity to express rate of heating-induced thermotolerance. Together, these results demonstrate that the polyamines, especially spermidine and spermine, enhance hyperthermia-induced cell killing by some mechanism involving the plasma membrane. Further, our data suggest that methylglyoxal bis-(guanylhydrazone) can act to affect thermal responses by a mechanism(s) other than modification of intracellular polyamine levels.

  4. Degradation of hydroxycinnamic acid mixtures in aqueous sucrose solutions by the Fenton process.

    PubMed

    Nguyen, Danny M T; Zhang, Zhanying; Doherty, William O S

    2015-02-11

    The degradation efficiencies and behaviors of caffeic acid (CaA), p-coumaric acid (pCoA), and ferulic acid (FeA) in aqueous sucrose solutions containing the mixture of these hydroxycinnamic acids (HCAs) were studied by the Fenton oxidation process. Central composite design and multiresponse surface methodology were used to evaluate and optimize the interactive effects of process parameters. Four quadratic polynomial models were developed for the degradation of each individual acid in the mixture and the total HCAs degraded. Sucrose was the most influential parameter that significantly affected the total amount of HCA degraded. Under the conditions studied there was a <0.01% loss of sucrose in all reactions. The optimal values of the process parameters for a 200 mg/L HCA mixture in water (pH 4.73, 25.15 °C) and sucrose solution (13 mass %, pH 5.39, 35.98 °C) were 77% and 57%, respectively. Regression analysis showed goodness of fit between the experimental results and the predicted values. The degradation behavior of CaA differed from those of pCoA and FeA, where further CaA degradation is observed at increasing sucrose and decreasing solution pH. The differences (established using UV/vis and ATR-FTIR spectroscopy) were because, unlike the other acids, CaA formed a complex with Fe(III) or with Fe(III) hydrogen-bonded to sucrose and coprecipitated with lepidocrocite, an iron oxyhydroxide.

  5. Polyamines in Eukaryotes, Bacteria, and Archaea.

    PubMed

    Michael, Anthony J

    2016-07-15

    Polyamines are primordial polycations found in most cells and perform different functions in different organisms. Although polyamines are mainly known for their essential roles in cell growth and proliferation, their functions range from a critical role in cellular translation in eukaryotes and archaea, to bacterial biofilm formation and specialized roles in natural product biosynthesis. At first glance, the diversity of polyamine structures in different organisms appears chaotic; however, biosynthetic flexibility and evolutionary and ecological processes largely explain this heterogeneity. In this review, I discuss the biosynthetic, evolutionary, and physiological processes that constrain or expand polyamine structural and functional diversity.

  6. The effect of feeding with a tryptophan-free amino acid mixture on rat liver magnesium ion-activated deoxyribonucleic acid-dependent ribonucleic acid polymerase

    PubMed Central

    Henderson, A. R.

    1970-01-01

    1. The Widnell & Tata (1966) assay method for Mg2+-activated DNA-dependent RNA polymerase was used for initial-velocity determinations of rat liver nuclear RNA polymerase. One unit (U) of RNA polymerase was defined as that amount of enzyme required for 1 mmol of [3H]GMP incorporation/min at 37°C. 2. Colony fed rats were found to have a mean RNA polymerase activity of 65.9μU/mg of DNA and 18h-starved rats had a mean activity of 53.2μU/mg of DNA. Longer periods of starvation did not significantly decrease RNA polymerase activity further. 3. Rats that had been starved for 18h were used for all feeding experiments. Complete and tryptophan-deficient amino acid mixtures were given by stomach tube and the animals were killed 15–120min later. The response of RNA polymerase to the feeding with the complete amino acid mixture was rapid and almost linear over the first hour of feeding, resulting in a doubling of activity. The activity was still elevated above the starvation value at 120min after feeding. The tryptophan-deficient amino acid mixture produced a much less vigorous response about 45min after the feeding, and the activity had returned to the starvation value by 120min after the feeding. 4. The response of RNA polymerase to the feeding with the complete amino acid mixture was shown to occur within a period of less than 5min to about 10min after the feeding. 5. Pretreatment of the animals with puromycin or cycloheximide was found to abolish the 15min RNA polymerase response to the feeding with the complete amino acid mixture, but the activity of the controls was unaffected. 6. The characteristics of the RNA polymerase from 18h-starved animals and animals fed with the complete or incomplete amino acid mixtures for 1h were examined. The effects of Mg2+ ions, pH, actinomycin D and nucleoside triphosphate omissions were determined. The [Mg2+]– and pH–activity profiles of the RNA polymerase from the animal fed with the complete mixture appeared to differ from

  7. Amino acid mixture acutely improves the glucose tolerance of healthy overweight adults.

    PubMed

    Wang, Bei; Kammer, Lynne M; Ding, Zhenping; Lassiter, David G; Hwang, Jungyun; Nelson, Jeffrey L; Ivy, John L

    2012-01-01

    Certain amino acids have been reported to influence carbohydrate metabolism and blood glucose clearance, as well as improve the glucose tolerance in animal models. We hypothesized that an amino acid mixture consisting of isoleucine and 4 additional amino acids would improve the glucose response of healthy overweight men and women to an oral glucose tolerance test (OGTT). Twenty-two overweight healthy subjects completed 2 OGTTs after consuming 2 different test beverages. The amino acid mixture beverage (CHO/AA) consisted of 0.088 g cystine 2HCl, 0.043 g methionine, 0.086 g valine, 12.094 g isoleucine, 0.084 g leucine, and 100 g dextrose. The control beverage (CHO) consisted of 100 g dextrose only. Venous blood samples were drawn 10 minutes before the start of ingesting the drinks and 15, 30, 60, 120, and 180 minutes after the completion of the drinks. During the OGTT, the plasma glucose response for the CHO/AA treatment was significantly lower than that of the CHO treatment (P < .01), as was the plasma glucose area under the curve (CHO/AA 806 ± 31 mmol/L·3 hours vs CHO 942 ± 40 mmol/L·3 hours). Differences in plasma glucose between treatments occurred at 30, 60, 120, and 180 minutes after supplement ingestion. Plasma glucagon during the CHO/AA treatment was significantly higher than during the CHO treatment. However, there were no significant differences in plasma insulin or C-peptide responses between treatments. These results suggest that the amino acid mixture lowers the glucose response to an OGTT in healthy overweight subjects in an insulin-independent manner.

  8. Iodometric microdetermination of boric acid and borax separately or in a mixture.

    PubMed

    Saxena, R; Verma, R M

    1983-05-01

    Boric acid is determined by first treating it with mannitol and then with solid potassium iodate and potassium iodide. The iodine liberated is titrated with thiosulphate. Borax is determined by reacting it with a known and excessive volume of hydrochloric acid and determining the surplus acid by iodometry. From the amount of acid consumed, the quantity of borax is calculated. Mixtures of borax and boric acid are analysed by combination of the two methods. Borax is determined first, then the mannitol procedure is applied to a second sample and the total boric acid (original plus that produced in the borax-HCl reaction) is determined iodometrically. The boric acid content of the sample is obtained by difference. The procedures can be used for determining 0.01-0.1 mmole of these substances with an average deviation of 0.1-0.4%. The end-points obtained are sharper than those for potentiometric acid-base titrations. Furthermore, the procedures are applicable at much lower concentrations.

  9. Protein cross-linking by chlorinated polyamines and transglutamylation stabilizes neutrophil extracellular traps

    PubMed Central

    Csomós, Krisztián; Kristóf, Endre; Jakob, Bernadett; Csomós, István; Kovács, György; Rotem, Omri; Hodrea, Judit; Bagoly, Zsuzsa; Muszbek, Laszlo; Balajthy, Zoltán; Csősz, Éva; Fésüs, László

    2016-01-01

    Neutrophil extracellular trap (NET) ejected from activated dying neutrophils is a highly ordered structure of DNA and selected proteins capable to eliminate pathogenic microorganisms. Biochemical determinants of the non-randomly formed stable NETs have not been revealed so far. Studying the formation of human NETs we have observed that polyamines were incorporated into the NET. Inhibition of myeloperoxidase, which is essential for NET formation and can generate reactive chlorinated polyamines through hypochlorous acid, decreased polyamine incorporation. Addition of exogenous primary amines that similarly to polyamines inhibit reactions catalyzed by the protein cross-linker transglutaminases (TGases) has similar effect. Proteomic analysis of the highly reproducible pattern of NET components revealed cross-linking of NET proteins through chlorinated polyamines and ɛ(γ-glutamyl)lysine as well as bis-γ-glutamyl polyamine bonds catalyzed by the TGases detected in neutrophils. Competitive inhibition of protein cross-linking by monoamines disturbed the cross-linking pattern of NET proteins, which resulted in the loss of the ordered structure of the NET and significantly reduced capacity to trap bacteria. Our findings provide explanation of how NETs are formed in a reproducible and ordered manner to efficiently neutralize microorganisms at the first defense line of the innate immune system. PMID:27512953

  10. Innovative approaches to the use of polyamines for DNA nanoparticle preparation for gene therapy.

    PubMed

    Vijayanathan, Veena; Agostinelli, Enzo; Thomas, Thresia; Thomas, T J

    2014-03-01

    Advances in genomic technologies, such as next generation sequencing and disease specific gene targeting through anti-sense, anti-gene, siRNA and microRNA approaches require the transport of nucleic acid drugs through the cell membrane. Membrane transport of DNA/RNA drugs is an inefficient process, and the mechanism(s) by which this process occurs is not clear. A pre-requisite for effective transport of DNA and RNA in cells is their condensation to nanoparticles of ~100 nm size. Although viral vectors are effective in gene therapy, the immune response elicited by viral proteins poses a major challenge. Multivalent cations, such as natural polyamines are excellent promoters of DNA/RNA condensation to nanoparticles. During the past 20 years, our laboratory has synthesized and tested several analogs of the natural polyamine, spermine, for their efficacy to provoke DNA condensation to nanoparticles. We determined the thermodynamics of polyamine-mediated DNA condensation, measured the structural specificity effects of polyamine analogs in facilitating the cellular uptake of oligonucleotides, and evaluated the gene silencing activity of DNA nanoparticles in breast cancer cells. Polyamine-complexed oligonucleotides showed a synergistic effect on target gene inhibition at the mRNA level compared to the use of polyamines and oligonucleotides as single agents. Ionic and structural specificity effects were evident in DNA condensation and cellular transportation effects of polyamines. In condensed DNA structures, correlation exists between the attractive and repulsive forces with structurally different polyamines and cobalt hexamine, indicating the existence of a common force in stabilizing the condensed structures. Future studies aimed at defining the mechanism(s) of DNA compaction and structural features of DNA nanoparticles might aid in the development of novel gene delivery vehicles.

  11. Hydrophobicity-dependent QSARs to predict the toxicity of perfluorinated carboxylic acids and their mixtures.

    PubMed

    Wang, Ting; Lin, Zhifen; Yin, Daqiang; Tian, Dayong; Zhang, Yalei; Kong, Deyang

    2011-09-01

    Perfluorinated carboxylic acids (PFCAs) have wide industrial applications because of their unique physicochemical characteristics. However, data on the toxicity of much of this chemical class is lacking, particularly with regard to mixture toxicity. In this study, the toxicity of individual PFCAs and their mixtures to Photobacterium phosphoreum were observed. There was a tendency of increasing toxicity from C3 to C14 PFCA and a tendency of decreasing toxicity from C14 to C18 PFCA because of "the maximum tolerance of the cell membrane". Using the equivalent logK(OW) (octanol-water partition coefficient) and logK(SD) (C(18)-Empore™ disks/water partition coefficient), two linear quantitative structure-activity relationship (QSAR) models were formulated. This indicated both K(SD) and K(OW) can describe the hydrophobicity of a single chemical. However, for the PFCA mixtures, K(MD) is the more reasonable parameter than K(owmix) to describe the hydrophobicity because only the equivalent logK(MD) could be used to predict the mixture toxicity.

  12. Thermal properties of phosphoric acid-doped polybenzimidazole membranes in water and methanol-water mixtures

    NASA Astrophysics Data System (ADS)

    Nores-Pondal, Federico J.; Buera, M. Pilar; Corti, Horacio R.

    The thermal properties of phosphoric acid-doped poly[2-2‧-(m-phenylene)-5-5‧ bi-benzimidazole] (PBI) and poly[2,5-benzimidazole] (ABPBI) membranes, ionomeric materials with promising properties to be used as electrolytes in direct methanol and in high temperature polymer electrolyte membrane (PEM) fuel cells, were studied by means of differential scanning calorimetry (DSC) technique in the temperature range from -145 °C to 200 °C. The DSC scans of samples equilibrated in water at different relative humidities (RH) and in liquid water-methanol mixtures were analyzed in relation to glass transition, water crystallization/melting and solvent desorption in different temperature regions. The thermal relaxation observed in the very low temperature region could be ascribed to the glass transition of the H 3PO 4-H 2O mixture confined in the polymeric matrix. After cooling the samples up to -145 °C, frozen water was detected in PBI and ABPBI at different RH, although at 100% RH less amount of water had crystallized than that observed in Nafion membranes under the same conditions. Even more important is the fact that the freezing degree of water is much lower in ABPBI membranes equilibrated in liquid water-methanol mixtures than that observed for PBI and, in a previous study, for Nafion. Thus, apart from other well known properties, acid-doped ABPBI emerges as an excellent ionomer for applications in direct methanol fuel cells working in cold environments.

  13. Significance of targeting polyamine metabolism as an antineoplastic strategy: unique targets for polyamine analogues.

    PubMed

    Casero, Robert A; Frydman, Benjamin; Stewart, Tracy Murray; Woster, Patrick M

    2005-01-01

    The polyamines, putrescine, spermidine, and spermine, are naturally occurring polycationic alkylamines that are absolutely required for eukaryotic cell growth. Importantly, the polyamine metabolic pathway, as well as the requirement of polyamines for cell growth, is frequently dysregulated in cancer cells, thus providing a unique set of targets for therapeutic intervention. Ornithine decarboxylase (ODC), a rate-limiting enzyme in polyamine biosynthesis, is frequently up-regulated in preneoplastic cells, and has been implicated as an oncogene in multiple tumor types. Several model systems have demonstrated that inhibition of ODC's enzymatic activity and down-regulation of its expression are rational strategies for both chemotherapy and chemoprevention. Specific inhibitors of ODC, most notably 2-difluoromethylornithine (DFMO), have been used experimentally to validate polyamine metabolism as an antineoplastic strategy. However, multiple biochemical and clinical limitations to these ODC-targeting strategies minimize their value as therapeutic tools. Included among these limitations are poor bioavailability of the inhibitor, and the compensatory up-regulation of polyamine metabolism and transport that allow tumor cells to escape the growth inhibitory effects of blockers specifically targeting ODC. As a strategy to overcome the limitations of direct enzyme inhibition, several groups have pursued the design of polyamine analogues that specifically target the dysregulated polyamine metabolism found in tumors. These analogues have been developed specifically to target the specific polyamine transporter, thus competing with circulating natural polyamines. Additionally, most of the analogues examined thus far maintain the regulatory function of the natural polyamines, but are unable to functionally substitute for them in promoting growth. Specifically, individual analogues have demonstrated the ability to down-regulate each of the biosynthetic enzymes without causing

  14. Nutritive value of globin-amino acid and complementary globin-cereal mixtures.

    PubMed

    Landmann, W A; Dill, C W; Young, C R

    1980-11-01

    Protein efficiency ratios (PER) were determined using male weanling rats fed diets containing bovine globin alone and with wheat and corn gluten. Simultaneous equations and graphical methods were devised for selecting combinations of globin and cereal proteins to provide optimal and suboptimal profiles of limiting amino acids. Supplementation of the globin with amino acids established isoleucine and methionine as limiting amino acids. Addition of globin, whose amino acid pattern is complementary to that of the cereal proteins, markedly improved the PER values of the proteins. However, growth rates of rats fed various combinations of proteins were not identical, even though PER values differed only slightly. The PER of combined proteins were not predictable from amino acid composition or from correlations between PER and chemical score based on National Research Council (NRC) requirements for essential amino acids. The inability of the optimal mixtures to meet expected nutritional performance clearly indicated that other factors affecting availability of amino acids are implicated. Nevertheless, mutual improvement of two incomplete proteins such as globin and wheat or corn gluten was demonstrated. Addition of globin to widely used diets consisting mainly of corn or wheat can be nutritionally beneficial.

  15. Validating the efficacy of peracetic acid mixture as an antimicrobial in poultry chillers.

    PubMed

    Bauermeister, Laura J; Bowers, Jordan W J; Townsend, Julie C; McKee, Shelly R

    2008-06-01

    Peracetic acid mixture (PAHP), which is a combination of peracetic acid and hydrogen peroxide, has been approved as an antimicrobial for use in poultry chillers. To validate its effectiveness, 85 ppm of PAHP was compared with the 30-ppm chlorine treatment in a commercial setting. In this trial, 100 carcasses were sampled for Salmonella and Campylobacter spp. prior to chilling and 100 carcasses were sampled after chilling. In all, 400 carcasses were sampled using 85 ppm of PAHP in the chiller and 400 carcasses were sampled using the chlorine treatment. PAHP at 85 ppm reduced Salmonella-positive carcasses by 92% exiting the chiller, whereas treatment with 30 ppm of chlorine reduced Salmonella by 57%. Additionally, PAHP reduced Campylobacter species-positive carcasses exiting the chiller by 43% while chlorine resulted in a 13% reduction. These results suggest that peracetic acid in combination with hydrogen peroxide may be an effective antimicrobial in poultry chiller applications.

  16. Effect of volatile fatty acids mixtures on the simultaneous photofermentative production of hydrogen and polyhydroxybutyrate.

    PubMed

    Cardeña, René; Valdez-Vazquez, Idania; Buitrón, Germán

    2017-02-01

    Purple non-sulfur bacteria generate hydrogen and polyhydroxybutyrate (PHB) as a mechanism for disposing of reducing equivalents generated during substrate consumption. However, both pathways compete for the reducing equivalents released from bacteria growing under certain substrates, thus the formation of hydrogen or PHB is detrimental to the formation of each other. The effect of mixtures of acetic, propionic and butyric acids on the formation of H2 and PHB was evaluated using Box-Behnken design. A bacterial community mainly constituted by Rhodopseudomonas palustris was used as inoculum. It was observed that the three volatile fatty acids had a significant effect on the specific PHB production. However, only the propionic acid had a significant effect on the specific H2 production activity and the highest value was observed when acetate was the main component in the mixture. The maximum values for the specific PHB and hydrogen production rates were 16.4 mg-PHB/g-TSS/day and 391 mL-H2/g-TSS/day, respectively.

  17. Simultaneous determination of rutin and ascorbic acid mixture in their pure forms and combined dosage form

    NASA Astrophysics Data System (ADS)

    Attia, Tamer Z.

    2016-12-01

    A simple, rapid, sensitive and selective high performance liquid chromatographic (HPLC) method with ultraviolet detection has been developed for simultaneous determination of ascorbic acid and rutin in pure forms and pharmaceutical dosage form. HPLC separation was performed on Phenomenex C18 analytical column with 0.1% v/v acetic acid in water and acetonitrile (75:25, v/v), as mobile phase. The separation was done at ambient temperature with flow rate of 1 mL·min- 1 in isocratic mode. HPLC measurements were carried out using ultraviolet detection wavelength at 257 nm. The average retention times were 2.72 and 7.00 min for ascorbic acid and rutin, respectively. The calibration plots were constructed over the concentration range of 5.0-30.0 for ascorbic acid and 10.0-60.0 μg·mL- 1 for rutin. The limits of detection were 1.06 and 1.89 μg·mL- 1 and limits of quantification were 3.54 and 6.31 μg·mL- 1 for ascorbic acid and rutin, respectively. The proposed HPLC-UV method was successfully applied for determination of ascorbic acid in its tablets and for simultaneous determination of the studied drugs in their laboratory prepared mixtures and in pharmaceutical formulation. Statistical comparisons of the results with the reference method show an excellent agreement and indicate no significant difference in respect to accuracy and precision.

  18. Amino Acid Mixture Enriched With Arginine, Alanine, and Phenylalanine Stimulates Fat Metabolism During Exercise.

    PubMed

    Ueda, Keisuke; Nakamura, Yutaka; Yamaguchi, Makoto; Mori, Takeshi; Uchida, Masayuki; Fujita, Satoshi

    2016-02-01

    Although there have been many investigations of the beneficial effects of both exercise and amino acids (AAs), little is known about their combined effects on the single-dose ingestion of AAs for lipid metabolism during exercise. We hypothesize that taking a specific combination of AAs implicated in glucagon secretion during exercise may increase fat metabolism. We recently developed a new mixture, d-AA mixture (D-mix), that contains arginine, alanine, and phenylalanine to investigate fat oxidation. In a double-blind, placebo-controlled crossover study, 10 healthy male volunteers were randomized to ingest either D-mix (3 g/dose) or placebo. Subjects in each condition subsequently performed a physical task that included workload trials on a cycle ergometer at 50% of maximal oxygen consumption for 1 hr. After oral intake of D-mix, maximum serum concentrations of glycerol (9.32 ± 6.29 mg/L and 5.22 ± 2.22 mg/L, respectively; p = .028), free fatty acid level (0.77 ± 0.26 mEq/L and 0.63 ± 0.28 mEq/L, respectively; p = .022), and acetoacetic acid levels (37.9 ± 17.7 μmol/L and 30.3 ± 13.9 μmol/L, respectively; p = .040) were significantly higher than in the placebo groups. The area under the curve for glucagon during recovery was numerically higher than placebo (6.61 ± 1.33 μg/L · min and 6.06 ± 1.23 μg/L · min, respectively; p = .099). These results suggest that preexercise ingestion of D-mix may stimulate fat metabolism. Combined with exercise, the administration of AA mixtures could prove to be a useful nutritional strategy to maximize fat metabolism.

  19. Pervaporation separation of ethanol-water mixtures using polyacrylic acid composite membranes

    DOEpatents

    Neidlinger, H.H.

    1985-05-07

    Synthetic, organic, polymeric membranes were prepared from polyacrylic acid salts for use with pervaporation apparatus in the separation of ehthanol-water mixtures. The polymeric material was prepared in dilute aqueous solution and coated onto a polysulfone support film, from which excess polymeric material was subsequently removed. Cross-links were then generated by limited exposure to toluene-2,4-diisocyanata solution, after which the prepared membrane was heat-cured. The resulting membrane structure showed selectivity in permeating water over a wide range of feed concentrations. 4 tabs.

  20. Fuel additives from SO/sub 2/ treated mixtures of amides and esters derived from vegetable oil, tall oil acid, or aralkyl acid

    SciTech Connect

    Efner, H. F.; Schiff, S.

    1985-03-12

    Vegetable oils, particularly soybean oil, tall oil acid, or aralkyl acids, particularly phenylstearic acid, are reacted with multiamines, particularly tetraethylenepentamine, to form a product mixture for subsequent reaction with SO/sub 2/ to produce a product mix that has good detergent properties in fuels.

  1. Ethanol, acetic acid, and water adsorption from binary and ternary liquid mixtures on high-silica zeolites.

    PubMed

    Bowen, Travis C; Vane, Leland M

    2006-04-11

    Adsorption isotherms were measured for ethanol, acetic acid, and water adsorbed on high-silica ZSM-5 zeolite powder from binary and ternary liquid mixtures at room temperature. Ethanol and water adsorption on two high-silica ZSM-5 zeolites with different aluminum contents and a high-silica beta zeolite were also compared. The amounts adsorbed were measured using a recently developed technique that accurately measures the changes in adsorbent/liquid mixture density and liquid concentration. This technique allows the adsorption of each compound in a liquid mixture to be measured. Adsorption data for binary mixtures were fit with the dual-site extended Langmuir model, and the parameters were used to predict ternary adsorption isotherms for each compound with reasonable accuracy. In ternary mixtures, acetic acid competed with ethanol and water for adsorption sites and reduced ethanol adsorption more than it reduced water adsorption.

  2. Sensitization to heat by the polyamines and their analogs

    SciTech Connect

    Fuller, D.J.; Gerner, E.W.

    1983-07-01

    The polyamines putrescine, spermidine, and spermine have been shown to sensitize Chinese hamster ovary (CHO) cells to the cytotoxic effects of elevated temperatures. This sensitization occurs in the order spermine greater than spermidine greater than putrescine. A series of homologs of the diamine putrescine demonstrated little variance in the degree of potentiation until a chain length equivalent to that of spermidine was employed (1,8-diaminooctane). Two compounds bearing structural similarities to spermidine gave rather different results when combined with heat. Methylglyoxal bis(guanylhydrazone) (MGBG), an antiproliferative drug, sensitized cells to heat, while S-2-(3-aminopropylamino)-ethyl phosphoric acid (WR-2721), a radioprotector, had no measureable effect on 43 degrees C-induced cytotoxicity. Together, these results point out the primary importance of two terminal amino groups separated by either carbon, or carbon and nitrogen, atoms in an aliphatic chain in the observed sensitization of heat-induced cytotoxicity by polyamines. These data suggest specific dimensional characteristics of the presumed negatively charged structure(s) with which the polyamines are interacting to elicit this effect.

  3. Experimental densities of binary mixtures: Acetic acid with benzene at several temperatures

    NASA Astrophysics Data System (ADS)

    Bolat, Georgiana; Sutiman, Daniel; Lisa, Gabriela

    2011-03-01

    Hydrocarbons are the most commonly used chemicals in the hydrocarbon processing industries. The knowledge of thermodynamic properties of various binary organic or inorganic mixtures is essential in many practical aspects concerning the mass transport and fluid flow. Such properties are important from the fundamental point of view to understand their mixing behaviour (molecular interactions), as well for practical applications (e.g. in the petrochemical industry). The density of acetic acid-benzene mixtures at several temperatures (T = 296.15, 302.15, 308.15, 314.15 and 319.15 K) were measured over the whole composition range and atmospheric pressure, along with the physical-chemical properties of the pure components (e.g. density, viscosity, refractive index at 298.15 K). The excess molar volumes at the above-mentioned temperatures were calculated from experimental data and fitted by using a new polynomial equation comparing the results with the known equation of Redlich-Kister. The excess volumes for acetic acid with benzene were positive and increase with the temperature. Results were analyzed in terms of molecular interactions. This research was financed by the postdoc grant PERFORM-ERA-ID 57649.

  4. A simple method for the titration of multicomponent acid-base mixtures.

    PubMed

    Moisio, T; Heikonen, M

    1996-01-01

    A titration method has been developed to analyze acid mixtures, in which the pK values differed by 0.5 to 1 pH units. Instead of the use of equivalence points a buffer capacity curve is numerically derived from the titration curve resulting in a presentation similar to chromatograms and spectra. The consumption of the NaOH titrant is determined within pH intervals of 0.2-0.6 units around the pK values of the components. The buffer capacity measured is expressed as the consumption of NaOH over the pH interval. The amounts of compounds are found from these results using simple models of chemometrics. The method has been applied to a mixture of formic and acetic acids with concentrations of 0-3 mmol/20 ml with an error of 0-0.05 mmol. Furthermore a curve-fitting method based on a theoretical equation of buffer capacity can be applied with an error slightly larger than with the previous method. In this case, the pK values were also computed. For titrations beyond the pH range 4-10, the buffer capacity of water has to be subtracted from the titration results. The whole procedure requires including the computations about 3-6 min.

  5. Polyamines and abiotic stress tolerance in plants

    PubMed Central

    Gill, Sarvajeet Singh

    2010-01-01

    Environmental stresses including climate change, especially global warming, are severely affecting plant growth and productivity worldwide. It has been estimated that two-thirds of the yield potential of major crops are routinely lost due to the unfavorable environmental factors. On the other hand, the world population is estimated to reach about 10 billion by 2050, which will witness serious food shortages. Therefore, crops with enhanced vigour and high tolerance to various environmental factors should be developed to feed the increasing world population. Maintaining crop yields under adverse environmental stresses is probably the major challenge facing modern agriculture where polyamines can play important role. Polyamines (PAs)(putrescine, spermidine and spermine) are group of phytohormone-like aliphatic amine natural compounds with aliphatic nitrogen structure and present in almost all living organisms including plants. Evidences showed that polyamines are involved in many physiological processes, such as cell growth and development and respond to stress tolerance to various environmental factors. In many cases the relationship of plant stress tolerance was noted with the production of conjugated and bound polyamines as well as stimulation of polyamine oxidation. Therefore, genetic manipulation of crop plants with genes encoding enzymes of polyamine biosynthetic pathways may provide better stress tolerance to crop plants. Furthermore, the exogenous application of PAs is also another option for increasing the stress tolerance potential in plants. Here, we have described the synthesis and role of various polyamines in abiotic stress tolerance in plants. PMID:20592804

  6. Polyamine biosynthetic diversity in plants and algae.

    PubMed

    Fuell, Christine; Elliott, Katherine A; Hanfrey, Colin C; Franceschetti, Marina; Michael, Anthony J

    2010-07-01

    Polyamine biosynthesis in plants differs from other eukaryotes because of the contribution of genes from the cyanobacterial ancestor of the chloroplast. Plants possess an additional biosynthetic route for putrescine formation from arginine, consisting of the enzymes arginine decarboxylase, agmatine iminohydrolase and N-carbamoylputrescine amidohydrolase, derived from the cyanobacterial ancestor. They also synthesize an unusual tetraamine, thermospermine, that has important developmental roles and which is evolutionarily more ancient than spermine in plants and algae. Single-celled green algae have lost the arginine route and are dependent, like other eukaryotes, on putrescine biosynthesis from the ornithine. Some plants like Arabidopsis thaliana and the moss Physcomitrella patens have lost ornithine decarboxylase and are thus dependent on the arginine route. With its dependence on the arginine route, and the pivotal role of thermospermine in growth and development, Arabidopsis represents the most specifically plant mode of polyamine biosynthesis amongst eukaryotes. A number of plants and algae are also able to synthesize unusual polyamines such as norspermidine, norspermine and longer polyamines, and biosynthesis of these amines likely depends on novel aminopropyltransferases similar to thermospermine synthase, with relaxed substrate specificity. Plants have a rich repertoire of polyamine-based secondary metabolites, including alkaloids and hydroxycinnamic amides, and a number of polyamine-acylating enzymes have been recently characterised. With the genetic tools available for Arabidopsis and other model plants and algae, and the increasing capabilities of comparative genomics, the biological roles of polyamines can now be addressed across the plant evolutionary lineage.

  7. Stabilization of Erythrocyte Membranes by Polyamines

    NASA Astrophysics Data System (ADS)

    Ballas, Samir K.; Mohandas, Narla; Marton, Laurence J.; Shohet, Stephen B.

    1983-04-01

    Using a laser diffraction technique, we have studied the effects of putrescine, spermidine, and spermine, the three physiologic polyamines, on the deformability and mechanical stability of human erythrocyte membranes. Ghosts resealed with polyamines were subjected to high fluid shear stress in an ektacytometer. All polyamines increased the membrane shear modulus (decreased deformability) in a concentration- and time-dependent manner. The order of effectiveness was spermine > spermidine > putrescine. At 10 μ M, spermine appreciably decreased membrane deformability. For the measurement of membrane mechanical stability, resealed ghosts were subjected to constant high shear stress in the ektacytometer and deformability was continuously recorded as the deformable ghosts fragmented into rigid spherical vesicles. Polyamines, especially spermine, caused a noticeable increase in the t1/2 for fragmentation. These effects could not be ascribed to proteolysis or Ca2+-induced transglutamination. That the effects of polyamines were specific and not simply due to their positive charge was demonstrated by the finding that Ca2+ and Mg2+ destabilized the erythrocyte membrane as evidenced by decreasing the t1/2 for fragmentation. Extracellular polyamines were not effective except under conditions that caused significant accumulation inside the cell. The data indicate that intracellular physiologic polyamines, especially spermine, decrease erythrocyte membrane deformability and stabilize the membrane skeleton, making it more resistant to fragmentation.

  8. Current status of the polyamine research field.

    PubMed

    Pegg, Anthony E; Casero, Robert A

    2011-01-01

    This chapter provides an overview of the polyamine field and introduces the 32 other chapters that make up this volume. These chapters provide a wide range of methods, advice, and background relevant to studies of the function of polyamines, the regulation of their content, their role in disease, and the therapeutic potential of drugs targeting polyamine content and function. The methodology provided in this new volume will enable laboratories already working in this area to expand their experimental techniques and facilitate the entry of additional workers into this rapidly expanding field.

  9. Current Status of the Polyamine Research Field

    PubMed Central

    Pegg, Anthony E.; Casero, Robert A.

    2013-01-01

    This chapter provides an overview of the polyamine field and introduces the 32 other chapters that make up this volume. These chapters provide a wide range of methods, advice, and background relevant to studies of the function of polyamines, the regulation of their content, their role in disease, and the therapeutic potential of drugs targeting polyamine content and function. The methodology provided in this new volume will enable laboratories already working in this area to expand their experimental techniques and facilitate the entry of additional workers into this rapidly expanding field. PMID:21318864

  10. The role of polyamines in protein-dependent hypoxic tolerance of Drosophila

    PubMed Central

    Vigne, Paul; Frelin, Christian

    2008-01-01

    Background Chronic hypoxia is a major component of ischemic diseases such as stroke or myocardial infarction. Drosophila is more tolerant to hypoxia than most mammalian species. It is considered as a useful model organism to identify new mechanisms of hypoxic tolerance. The hypoxic tolerance of flies has previously been reported to be enhanced by low protein diets. This study analyses the mechanisms involved. Results Feeding adult Drosophila on a yeast diet dramatically reduced their longevities under chronic hypoxic conditions (5% O2). Mean and maximum longevities became close to the values observed for starving flies. The action of dietary yeast was mimicked by a whole casein hydrolysate and by anyone of the 20 natural amino acids that compose proteins. It was mimicked by amino acid intermediates of the urea cycle such as L-citrulline and L-ornithine, and by polyamines (putrescine, spermidine and spermine). α-difluoromethylornithine, a specific inhibitor of ornithine decarboxylase, partially protected hypoxic flies from amino acid toxicity but not from polyamine toxicity. N1-guanyl-1,7 diaminoheptane, a specific inhibitor of eIF5A hypusination, partially relieved the toxicities of both amino acids and polyamines. Conclusion Dietary amino acids reduced the longevity of chronically hypoxic flies fed on a sucrose diet. Pharmacological evidence suggests that the synthesis of polyamines and the hypusination of eIF5A contributed to the life-shortening effect of dietary amino acids. PMID:19055734

  11. A traceable reference for direct comparative assessment of total naphthenic acid concentrations in commercial and acid extractable organic mixtures derived from oil sands process water.

    PubMed

    Brunswick, Pamela; Hewitt, L Mark; Frank, Richard A; Kim, Marcus; van Aggelen, Graham; Shang, Dayue

    2017-02-23

    The advantage of using naphthenic acid (NA) mixtures for the determination of total NA lies in their chemical characteristics and identification of retention times distinct from isobaric interferences. However, the differing homolog profiles and unknown chemical structures of NA mixtures do not allow them to be considered a traceable reference material. The current study provides a new tool for the comparative assessment of different NA mixtures by direct reference to a single, well-defined and traceable compound, decanoic-d19 acid. The method employed an established liquid chromatography time-of-flight mass spectrometry (LC/QToF) procedure that was applicable both to the classic O2 NA species dominating commercial mixtures and additionally to the O4 species known to be present in acid extractable organics (AEOs) derived from oil sands process water (OSPW). Four different commercial NA mixtures and one OSPW-derived AEOs mixture were comparatively assessed. Results showed significant difference among Merichem Technical, Aldrich, Acros, and Kodak commercial NA mixtures with respect to "equivalent to decanoic-d19 acid" concentration ratios to nominal. Furthermore, different lot numbers of single commercial NA mixtures were found to be inconsistent with respect to their homolog content by percent response. Differences in the observed homolog content varied significantly, particularly at the lower (n = 9-14) and higher (n = 20-23) carbon number ranges. Results highlighted the problem between using NA mixtures from different sources and different lot numbers but offered a solution to the problem from a concentration perspective. It is anticipated that this tool may be utilized in review of historical data in addition to future studies, such as the study of OSPW derived acid extractable organics (AEOs) and fractions employed during toxicological studies.

  12. Polyamines and cancer: implications for chemotherapy and chemoprevention.

    PubMed

    Nowotarski, Shannon L; Woster, Patrick M; Casero, Robert A

    2013-02-22

    Polyamines are small organic cations that are essential for normal cell growth and development in eukaryotes. Under normal physiological conditions, intracellular polyamine concentrations are tightly regulated through a dynamic network of biosynthetic and catabolic enzymes, and a poorly characterised transport system. This precise regulation ensures that the intracellular concentration of polyamines is maintained within strictly controlled limits. It has frequently been observed that the metabolism of, and the requirement for, polyamines in tumours is frequently dysregulated. Elevated levels of polyamines have been associated with breast, colon, lung, prostate and skin cancers, and altered levels of rate-limiting enzymes in both biosynthesis and catabolism have been observed. Based on these observations and the absolute requirement for polyamines in tumour growth, the polyamine pathway is a rational target for chemoprevention and chemotherapeutics. Here we describe the recent advances made in the polyamine field and focus on the roles of polyamines and polyamine metabolism in neoplasia through a discussion of the current animal models for the polyamine pathway, chemotherapeutic strategies that target the polyamine pathway, chemotherapeutic clinical trials for polyamine pathway-specific drugs and ongoing clinical trials targeting polyamine biosynthesis.

  13. Polyamines and cancer: Implications for chemoprevention and chemotherapy

    PubMed Central

    Nowotarski, Shannon L.; Woster, Patrick M.; Casero, Robert A.

    2013-01-01

    Polyamines are small organic cations that are essential for normal cell growth and development in eukaryotes. Under normal physiological conditions, intracellular polyamine concentrations are tightly regulated through a dynamic network of biosynthetic and catabolic enzymes and a poorly characterized transport system. This precise regulation ensures that the intracellular concentration of polyamines is maintained within strictly controlled limits. It has frequently been observed that the metabolism of, and the requirement for, polyamines in tumours is frequently dysregulated. Elevated levels of polyamines have been associated with breast, colon, lung, prostate, and skin cancers, and altered levels of the rate limiting enzymes in both biosynthesis and catabolism have been observed. Based on these observations and the absolute requirement for polyamines in tumour growth, the polyamine pathway is a rational target for chemoprevention and chemotherapeutics. Here we describe the recent advances made in the polyamine field and focus on the roles of polyamines and polyamine metabolism in neoplasia through a discussion of the current animal models for the polyamine pathway, chemotherapeutic strategies that target the polyamine pathway, chemotherapeutic clinical trials for polyamine pathway specific drugs, and ongoing clinical trials targeting polyamine biosynthesis. PMID:23432971

  14. Stress and polyamine metabolism in fungi

    PubMed Central

    Valdés-Santiago, Laura; Ruiz-Herrera, José

    2013-01-01

    Fungi, as well as the rest of living organisms must deal with environmental challenges such as stressful stimuli. Fungi are excellent models to study the general mechanisms of the response to stress, because of their simple, but conserved, signal-transduction and metabolic pathways that are often equivalent to those present in other eukaryotic systems. A factor that has been demonstrated to be involved in these responses is polyamine metabolism, essentially of the three most common polyamines: putrescine, spermidine and spermine. The gathered evidences on this subject suggest that polyamines are able to control cellular signal transduction, as well as to modulate protein-protein interactions. In the present review, we will address the recent advances on the study of fungal metabolism of polyamines, ranging from mutant characterization to potential mechanism of action during different kinds of stress in selected fungal models. PMID:24790970

  15. Polyamines in the male reproductive system.

    PubMed

    Calandra, R S; Rulli, S B; Frungieri, M B; Suescun, M O; González-Calvar, S I

    1996-01-01

    This review covers some common aspects of the biosynthesis, interconversion pathways and biochemical functions of polyamines. A particular emphasis is given in experimental models as well as humans, to their presence in the male gonad, prostate gland, seminal vesicles, epididymis and semen. The interaction between hormones (androgens, LH, FSH and PRL) and the main enzymes involved on the polyamine biosynthesis, and the relationship of these compounds on cell growth and differentiation, are also discussed. In this regard, an attention is offered to the potential role of polyamines during early spermatogenesis stages and the use of some enzymes involved in their biosynthesis as sensitive and specific markers of the action of androgens and antiandrogens in the epididymis. Finally, a special issue is addressed to the controversial information documented on polyamines, their oxidation products and the relationship with male fertility.

  16. Polyamines and regulation of ripening and senescence

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Polyamines (PAs) are small polycationic, biogenic amines that influence many biochemical and physiological processes such as cell division, cell elongation, flowering, fruit set and development, fruit ripening and senescence. Significant information about PA action has emerged from indirect studies ...

  17. Stress and Polyamine Metabolism in Fungi

    NASA Astrophysics Data System (ADS)

    Valdés-Santiago, Laura; Ruiz-Herrera, José

    2013-12-01

    Fungi, as well as the rest of living organisms must deal with environmental challenges such as stressful stimuli. Fungi are excellent models to study the general mechanisms of the response to stress, because of their simple, but conserved, signal-transduction and metabolic pathways that are often equivalent to those present in other eukaryotic systems. A factor that has been demonstrated to be involved in these responses is polyamine metabolism, essentially of the three most common polyamines: putrescine, spermidine and spermine. The gathered evidences on this subject suggest that polyamines are able to control cellular signal transduction, as well as to modulate protein-protein interactions. In the present review, we will address the recent advances on the study of fungal metabolism of polyamines, ranging from mutant characterization to potential mechanism of action during different kinds of stress in selected fungal models.

  18. Derivative-ratio spectrophotometric method for the determination of ternary mixture of aspirin, paracetamol and salicylic acid

    NASA Astrophysics Data System (ADS)

    El-Yazbi, Fawzi A.; Hammud, Hassan H.; Assi, Sulaf A.

    2007-10-01

    A derivative spectrophotometric method was developed for the assay of a ternary mixture of aspirin (ASP), paracetamol (PAR) and salicylic acid (SAL). The method is based on the use of the first and second derivatives of the ratio spectra and measurement at zero-crossing wavelengths. The ratio spectra were obtained by dividing the absorption spectrum of the mixture by that of one of the components. The concentration of the other components are then determined from their respective calibration curves treated similarly. The described method was applied for the determination of these combinations in synthetic mixtures and dosage forms. The results obtained were accurate and precise.

  19. Derivative-ratio spectrophotometric method for the determination of ternary mixture of aspirin, paracetamol and salicylic acid.

    PubMed

    El-Yazbi, Fawzi A; Hammud, Hassan H; Assi, Sulaf A

    2007-10-01

    A derivative spectrophotometric method was developed for the assay of a ternary mixture of aspirin (ASP), paracetamol (PAR) and salicylic acid (SAL). The method is based on the use of the first and second derivatives of the ratio spectra and measurement at zero-crossing wavelengths. The ratio spectra were obtained by dividing the absorption spectrum of the mixture by that of one of the components. The concentration of the other components are then determined from their respective calibration curves treated similarly. The described method was applied for the determination of these combinations in synthetic mixtures and dosage forms. The results obtained were accurate and precise.

  20. Enhanced Biocide Mitigation of Field Biofilm Consortia by a Mixture of D-Amino Acids

    PubMed Central

    Li, Yingchao; Jia, Ru; Al-Mahamedh, Hussain H.; Xu, Dake; Gu, Tingyue

    2016-01-01

    Microbiologically influenced corrosion (MIC) is a major problem in the oil and gas industry as well as in many other industries. Current treatment methods rely mostly on pigging and biocide dosing. Biocide resistance is a growing concern. Thus, it is desirable to use biocide enhancers to improve the efficacy of existing biocides. D-Amino acids are naturally occurring. Our previous work demonstrated that some D-amino acids are biocide enhancers. Under a biocide stress of 50 ppm (w/w) hydroxymethyl phosphonium sulfate (THPS) biocide, 1 ppm D-tyrosine and 100 ppm D-methionine used separately successfully mitigated the Desulfovibrio vulgaris biofilm on carbon steel coupons. The data reported in this work revealed that 50 ppm of an equimolar mixture of D-methionine, D-tyrosine, D-leucine, and D-tryptophan greatly enhanced 50 ppm THPS biocide treatment of two recalcitrant biofilm consortia containing sulfate reducing bacteria (SRB), nitrate reducing bacteria (NRB), and fermentative bacteria, etc., from oil-field operations. The data also indicated that individual D-amino acids were inadequate for the biofilm consortia. PMID:27379039

  1. Enhanced Biocide Mitigation of Field Biofilm Consortia by a Mixture of D-Amino Acids.

    PubMed

    Li, Yingchao; Jia, Ru; Al-Mahamedh, Hussain H; Xu, Dake; Gu, Tingyue

    2016-01-01

    Microbiologically influenced corrosion (MIC) is a major problem in the oil and gas industry as well as in many other industries. Current treatment methods rely mostly on pigging and biocide dosing. Biocide resistance is a growing concern. Thus, it is desirable to use biocide enhancers to improve the efficacy of existing biocides. D-Amino acids are naturally occurring. Our previous work demonstrated that some D-amino acids are biocide enhancers. Under a biocide stress of 50 ppm (w/w) hydroxymethyl phosphonium sulfate (THPS) biocide, 1 ppm D-tyrosine and 100 ppm D-methionine used separately successfully mitigated the Desulfovibrio vulgaris biofilm on carbon steel coupons. The data reported in this work revealed that 50 ppm of an equimolar mixture of D-methionine, D-tyrosine, D-leucine, and D-tryptophan greatly enhanced 50 ppm THPS biocide treatment of two recalcitrant biofilm consortia containing sulfate reducing bacteria (SRB), nitrate reducing bacteria (NRB), and fermentative bacteria, etc., from oil-field operations. The data also indicated that individual D-amino acids were inadequate for the biofilm consortia.

  2. Mixture tetracycline citric acid and detergent – A root canal irrigant. A review

    PubMed Central

    Srikumar, G.P.V.; Sekhar, K.S.; Nischith, K.G.

    2012-01-01

    Background Root canal irrigants play an indispensable role for the complete disinfection of the root canal system, in particular those areas of the root canal that are not accessible for instrumentation. Sodium hypochlorite, ethylene diamine tetra acetic acid, hydrogen peroxide and chlorhexidine are the most commonly used root canal irrigants in endodontic practice, but they do not satisfy all the properties of an ideal root canal irrigant. Mixture tetracycline, citric acid and detergent, a root canal irrigant, is commercially available as BioPure MTAD (Dentsply, Tulsa Dental, Tulsa, OK). Methodology The literature was searched for root canal irrigants used in the last 3 decades in PubMed. Data showed 83 relevant articles, of which 24 were found most suitable on the basis of description of properties, advantages and disadvantages of MTAD, hence were included. The aim of this study was to evaluate the properties of MTAD for its antibacterial efficiency, biocompatibility, chelating action with removal of endodontic smear layer and compare it with other commonly used root canal irrigants like sodium hypochlorite, ethylene diamine tetra acetic acid, hydrogen peroxide, chlorhexidine. Results MTAD was found to be highly effective intracanal irrigant compared to other commonly used root canal irrigants with excellent disinfection of the entire root canal system. Conclusion MTAD is biocompatible with superior antimicrobial efficiency compared to other commonly used root canal irrigants. PMID:25737877

  3. Lewis acid-base adducts: a quantitative Raman analysis of formamide and dimethylsulfoxide mixtures.

    PubMed

    Alves, Wagner A; Antunes, Octavio A C

    2007-07-01

    Raman spectra of pure liquid dimethylsulfoxide (DMSO) and of binary mixtures of formamide (FA) and DMSO in different compositions were obtained. The vibrations involving the SO functional group in the band envelope at ca. 1050 cm(-1) of pure liquid DMSO are assigned to monomers, dimers and higher aggregates of DMSO. The appearance of a new band at 1024 cm(-1), whose intensity shows large dependence on the FA concentration, is assigned to a FA-DMSO adduct. This has been possible due to the two H-bond donor sites of FA and the strong donor character of DMSO that become the environment propitious for the donor-acceptor reaction. Quantitative analysis performed in the SO stretching region in the binary mixtures gives a 1:1 stoichiometry in this adduct in the limit of infinite dilution. This proportion is in full agreement with our previous determination for the FA-ACN adduct. The experimental evidence of the 1:1 FA-DMSO adduct is presented for the first time using Raman spectroscopy. The results described here open new possibilities to study the acid-base reactions nature of FA adducts.

  4. Lewis acid-base adducts: A quantitative Raman analysis of formamide and dimethylsulfoxide mixtures

    NASA Astrophysics Data System (ADS)

    Alves, Wagner A.; Antunes, Octavio A. C.

    2007-07-01

    Raman spectra of pure liquid dimethylsulfoxide (DMSO) and of binary mixtures of formamide (FA) and DMSO in different compositions were obtained. The vibrations involving the SO functional group in the band envelope at ca. 1050 cm -1 of pure liquid DMSO are assigned to monomers, dimers and higher aggregates of DMSO. The appearance of a new band at 1024 cm -1, whose intensity shows large dependence on the FA concentration, is assigned to a FA-DMSO adduct. This has been possible due to the two H-bond donor sites of FA and the strong donor character of DMSO that become the environment propitious for the donor-acceptor reaction. Quantitative analysis performed in the SO stretching region in the binary mixtures gives a 1:1 stoichiometry in this adduct in the limit of infinite dilution. This proportion is in full agreement with our previous determination for the FA-ACN adduct. The experimental evidence of the 1:1 FA-DMSO adduct is presented for the first time using Raman spectroscopy. The results described here open new possibilities to study the acid-base reactions nature of FA adducts.

  5. Pervaporation of Water from Aqueous Hydriodic Acid and Iodine Mixtures Using Nafion (R) Membranes

    SciTech Connect

    Christopher J. Orme; Frederick F. Stewart

    2007-11-01

    The sulfur-iodine (S-I) process for generation of hydrogen has been proposed as a thermochemical cycle for study due to its predicted high efficiencies. Improvements in the cycle that will yield the greatest gain in both operating and capital costs involve chemical separations. To date, membrane processes have been largely unexplored. In this work, a materials compatibility study into the application of Nafion-117® and Nafion-112® as membranes for the pervaporation of water from aqueous mixtures of hydriodic acid (HI) and HI/iodine at 134 ºC was conducted. Significant fluxes of water were measured with respect to feed water concentration and high separation factors were calculated. Most surprisingly, HI and HI/iodine feeds acted very differently in that HI-iodine complexes formed result in higher fluxes and separation factors than what was observed for HI alone.

  6. Docosahexaenoic acid promotes micron scale liquid-ordered domains. A comparison study of docosahexaenoic versus oleic acid containing phosphatidylcholine in raft-like mixtures.

    PubMed

    Georgieva, R; Chachaty, C; Hazarosova, R; Tessier, C; Nuss, P; Momchilova, A; Staneva, G

    2015-06-01

    The understanding of the functional role of the lipid diversity in biological membranes is a major challenge. Lipid models have been developed to address this issue by using lipid mixtures generating liquid-ordered (Lo)/liquid-disordered (Ld) immiscibility. The present study examined mixtures comprising Egg sphingomyelin (SM), cholesterol (chol) and phosphatidylcholine (PC) either containing docosahexaenoic (PDPC) or oleic acid (POPC). The mixtures were examined in terms of their capability to induce phase separation at the micron- and nano-scales. Fluorescence microscopy, electron spin resonance (ESR), X-ray diffraction (XRD) and calorimetry methods were used to analyze the lateral organization of the mixtures. Fluorescence microscopy of giant vesicles could show that the temperature of the micron-scale Lo/Ld miscibility is higher for PDPC than for POPC ternary mixtures. At 37°C, no micron-scale Lo/Ld phase separation could be identified in the POPC containing mixtures while it was evident for PDPC. In contrast, a phase separation was distinguished for both PC mixtures by ESR and XRD, indicative that PDPC and POPC mixtures differed in micron vs nano domain organization. Compared to POPC, the higher line tension of the Lo domains observed in PDPC mixtures is assumed to result from the higher difference in Lo/Ld order parameter rather than hydrophobic mismatch.

  7. Glutamate, Ornithine, Arginine, Proline, and Polyamine Metabolic Interactions: The Pathway Is Regulated at the Post-Transcriptional Level

    PubMed Central

    Majumdar, Rajtilak; Barchi, Boubker; Turlapati, Swathi A.; Gagne, Maegan; Minocha, Rakesh; Long, Stephanie; Minocha, Subhash C.

    2016-01-01

    The metabolism of glutamate into ornithine, arginine, proline, and polyamines is a major network of nitrogen-metabolizing pathways in plants, which also produces intermediates like nitric oxide, and γ-aminobutyric acid (GABA) that play critical roles in plant development and stress. While the accumulations of intermediates and the products of this network depend primarily on nitrogen assimilation, the overall regulation of the interacting sub-pathways is not well understood. We tested the hypothesis that diversion of ornithine into polyamine biosynthesis (by transgenic approach) not only plays a role in regulating its own biosynthesis from glutamate but also affects arginine and proline biosynthesis. Using two high putrescine producing lines of Arabidopsis thaliana (containing a transgenic mouse ornithine decarboxylase gene), we studied the: (1) effects of exogenous supply of carbon and nitrogen on polyamines and pools of soluble amino acids; and, (2) expression of genes encoding key enzymes in the interactive pathways of arginine, proline and GABA biosynthesis as well as the catabolism of polyamines. Our findings suggest that: (1) the overall conversion of glutamate to arginine and polyamines is enhanced by increased utilization of ornithine for polyamine biosynthesis by the transgene product; (2) proline and arginine biosynthesis are regulated independently of polyamines and GABA biosynthesis; (3) the expression of most genes (28 that were studied) that encode enzymes of the interacting sub-pathways of arginine and GABA biosynthesis does not change even though overall biosynthesis of Orn from glutamate is increased several fold; and (4) increased polyamine biosynthesis results in increased assimilation of both nitrogen and carbon by the cells. PMID:26909083

  8. Control of Proton Sensitivity of the NMDA Receptor by RNA Splicing and Polyamines

    NASA Astrophysics Data System (ADS)

    Traynelis, Stephen F.; Hartley, Melissa; Heinemann, Stephen F.

    1995-05-01

    The function of the N-methyl-D-aspartate (NMDA)-preferring glutamate receptor can be regulated by extracellular pH, a process that may be important during ischemia in the brain or during seizures. Protons inhibit NMDA receptor function by 50 percent at pH 7.3 through interactions with the NR1 subunit, and both polyamines and NR1 exon 5 potentiate receptor function through relief of the tonic proton inhibition present at physiological pH. A single amino acid (lysine 211) was identified that mediates the effects of exon 5 in the rat brain. Electroneutral substitutions at this position restored pH sensitivity and, consequently, polyamine relief of tonic inhibition. This effect, together with the structural similarities between polyamines and the surface loop encoded by exon 5, suggest that exon 5 may act as a tethered pH-sensitive constitutive modulator of NMDA receptor function.

  9. On the abiotic formation of amino acids. I - HCN as a precursor of amino acids detected in extracts of lunar samples. II - Formation of HCN and amino acids from simulated mixtures of gases released from lunar samples

    NASA Technical Reports Server (NTRS)

    Yuasa, S.; Flory, D.; Basile, B.; Oro, J.

    1984-01-01

    Two studies on the abiotic formation of amino acids are presented. The first study demonstrates the role of hydrogen cyanide as a precursor of amino acids detected in extracts of lunar samples. The formation of several amino acids, including glycine, alanine, aspartic acid, and glutamic acid, under conditions similar to those used for the analysis of lunar samples is demonstrated. The second study investigates the formation of hydrogen cyanide as well as amino acids from lunar-sample gas mixtures under electrical discharge conditions. These results extend the possibility of synthesis of amino acids to planetary bodies with primordial atmospheres less reducing than a mixture of methane, ammonia, hydrogen and water.

  10. Gibbs ensemble Monte Carlo simulation using an optimized potential model: pure acetic acid and a mixture of it with ethylene.

    PubMed

    Zhang, Minhua; Chen, Lihang; Yang, Huaming; Sha, Xijiang; Ma, Jing

    2016-07-01

    Gibbs ensemble Monte Carlo simulation with configurational bias was employed to study the vapor-liquid equilibrium (VLE) for pure acetic acid and for a mixture of acetic acid and ethylene. An improved united-atom force field for acetic acid based on a Lennard-Jones functional form was proposed. The Lennard-Jones well depth and size parameters for the carboxyl oxygen and hydroxyl oxygen were determined by fitting the interaction energies of acetic acid dimers to the Lennard-Jones potential function. Four different acetic acid dimers and the proportions of them were considered when the force field was optimized. It was found that the new optimized force field provides a reasonable description of the vapor-liquid phase equilibrium for pure acetic acid and for the mixture of acetic acid and ethylene. Accurate values were obtained for the saturated liquid density of the pure compound (average deviation: 0.84 %) and for the critical points. The new optimized force field demonstrated greater accuracy and reliability in calculations of the solubility of the mixture of acetic acid and ethylene as compared with the results obtained with the original TraPPE-UA force field.

  11. Sulfuric acid-methanol electrolytes as an alternative to sulfuric-hydrofluoric acid mixtures for electropolishing of niobium

    SciTech Connect

    Zhao, Xin; Corcoran, Sean G.; Kelley, Michael J.

    2011-06-01

    Attainment of the greatest possible interior surface smoothness is critical to meeting the performance demands placed upon niobium superconducting radiofrequency (SRF) accelerator cavities by next generation projects. Electropolishing with HF-H{sub 2}SO{sub 4} electrolytes yields cavities that meet SRF performance goals, but a less-hazardous, more environmentally-friendly process is desirable. Reported studies of EP on chemically-similar tantalum describe the use of sulfuric acid-methanol electrolytes as an HF-free alternative. Reported here are the results of experiments on niobium samples with this electrolyte. Voltammetry experiments indicate a current plateau whose voltage range expands with increasing acid concentration and decreasing temperature. Impedance spectroscopy indicates that a compact salt film is responsible for the current plateau. Equivalent findings in electropolishing chemically-similar tantalum with this electrolyte were interpreted due to as mass transfer limitation by diffusion of Ta ions away from the anode surface. We infer that a similar mechanism is at work here. Conditions were found that yield leveling and brightening comparable to that obtained with HF-H{sub 2}SO{sub 4} mixtures.

  12. Biogenic and synthetic polyamines bind cationic dendrimers.

    PubMed

    Mandeville, Jean-Sebastian; Bourassa, Phillipe; Thomas, Thekkumkattil John; Tajmir-Riahi, Heidar-Ali

    2012-01-01

    Biogenic polyamines are essential for cell growth and differentiation, while polyamine analogues exert antitumor activity in multiple experimental model systems, including breast and lung cancer. Dendrimers are widely used for drug delivery in vitro and in vivo. We report the bindings of biogenic polyamines, spermine (spm), and spermidine (spmd), and their synthetic analogues, 3,7,11,15-tetrazaheptadecane.4HCl (BE-333) and 3,7,11,15,19-pentazahenicosane.5HCl (BE-3333) to dendrimers of different compositions, mPEG-PAMAM (G3), mPEG-PAMAM (G4) and PAMAM (G4). FTIR and UV-visible spectroscopic methods as well as molecular modeling were used to analyze polyamine binding mode, the binding constant and the effects of polyamine complexation on dendrimer stability and conformation. Structural analysis showed that polyamines bound dendrimers through both hydrophobic and hydrophilic contacts with overall binding constants of K(spm-mPEG-G3) = 7.6 × 10(4) M(-1), K(spm-mPEG-PAMAM-G4) = 4.6 × 10(4) M(-1), K(spm-PAMAM-G4) = 6.6 × 10(4) M(-1), K(spmd-mPEG-G3) = 1.0 × 10(5) M(-1), K(spmd-mPEG-PAMAM-G4) = 5.5 × 10(4) M(-1), K(spmd-PAMAM-G4) = 9.2 × 10(4) M(-1), K(BE-333-mPEG-G3) = 4.2 × 10(4) M(-1), K(Be-333-mPEG-PAMAM-G4) = 3.2 × 10(4) M(-1), K(BE-333-PAMAM-G4) = 3.6 × 10(4) M(-1), K(BE-3333-mPEG-G3) = 2.2 × 10(4) M(-1), K(Be-3333-mPEG-PAMAM-G4) = 2.4 × 10(4) M(-1), K(BE-3333-PAMAM-G4) = 2.3 × 10(4) M(-1). Biogenic polyamines showed stronger affinity toward dendrimers than those of synthetic polyamines, while weaker interaction was observed as polyamine cationic charges increased. The free binding energies calculated from docking studies were: -3.2 (spermine), -3.5 (spermidine) and -3.03 (BE-3333) kcal/mol, with the following order of binding affinity: spermidine-PAMAM-G-4>spermine-PAMMAM-G4>BE-3333-PAMAM-G4 consistent with spectroscopic data. Our results suggest that dendrimers can act as carrier vehicles for delivering antitumor polyamine analogues to target tissues.

  13. Biogenic and Synthetic Polyamines Bind Cationic Dendrimers

    PubMed Central

    Mandeville, Jean-Sebastian; Bourassa, Phillipe; Thomas, Thekkumkattil John; Tajmir-Riahi, Heidar-Ali

    2012-01-01

    Biogenic polyamines are essential for cell growth and differentiation, while polyamine analogues exert antitumor activity in multiple experimental model systems, including breast and lung cancer. Dendrimers are widely used for drug delivery in vitro and in vivo. We report the bindings of biogenic polyamines, spermine (spm), and spermidine (spmd), and their synthetic analogues, 3,7,11,15-tetrazaheptadecane.4HCl (BE-333) and 3,7,11,15,19-pentazahenicosane.5HCl (BE-3333) to dendrimers of different compositions, mPEG-PAMAM (G3), mPEG-PAMAM (G4) and PAMAM (G4). FTIR and UV-visible spectroscopic methods as well as molecular modeling were used to analyze polyamine binding mode, the binding constant and the effects of polyamine complexation on dendrimer stability and conformation. Structural analysis showed that polyamines bound dendrimers through both hydrophobic and hydrophilic contacts with overall binding constants of Kspm-mPEG-G3 = 7.6×104 M−1, Kspm-mPEG-PAMAM-G4 = 4.6×104 M−1, Kspm-PAMAM-G4 = 6.6×104 M−1, Kspmd-mPEG-G3 = 1.0×105 M−1, Kspmd-mPEG-PAMAM-G4 = 5.5×104 M−1, Kspmd-PAMAM-G4 = 9.2×104 M−1, KBE-333-mPEG-G3 = 4.2×104 M−1, KBe-333-mPEG-PAMAM-G4 = 3.2×104 M−1, KBE-333-PAMAM-G4 = 3.6×104 M−1, KBE-3333-mPEG-G3 = 2.2×104 M−1, KBe-3333-mPEG-PAMAM-G4 = 2.4×104 M−1, KBE-3333-PAMAM-G4 = 2.3×104 M−1. Biogenic polyamines showed stronger affinity toward dendrimers than those of synthetic polyamines, while weaker interaction was observed as polyamine cationic charges increased. The free binding energies calculated from docking studies were: −3.2 (spermine), −3.5 (spermidine) and −3.03 (BE-3333) kcal/mol, with the following order of binding affinity: spermidine-PAMAM-G-4>spermine-PAMMAM-G4>BE-3333-PAMAM-G4 consistent with spectroscopic data. Our results suggest that dendrimers can act as carrier vehicles for delivering antitumor polyamine analogues to target tissues. PMID:22558341

  14. DNA interaction with antitumor polyamine analogues: a comparison with biogenic polyamines.

    PubMed

    N'soukpoé-Kossi, C N; Ouameur, A Ahmed; Thomas, T; Shirahata, A; Thomas, T J; Tajmir-Riahi, H A

    2008-10-01

    Biogenic polyamines, putrescine, spermidine, and spermine, are ubiquitous cellular cations and exert multiple biological functions. Polyamine analogues mimic biogenic polyamines at macromolecular level but are unable to substitute for natural polyamines and maintain cell proliferation, indicating biomedical applications. The mechanistic differences in DNA binding mode between natural and synthetic polyamines have not been explored. The aim of this study was to examine the interaction of calf thymus DNA with three polyamine analogues, 1,11-diamino-4,8-diazaundecane (333), 3,7,11,15-tetrazaheptadecane x 4 HCl (BE-333), and 3,7,11,15,19-pentazahenicosane x 5 HCl (BE-3333), using FTIR, UV-visible, and CD spectroscopy. Polyamine analogues bind with guanine and backbone PO2 group as major targets in DNA, whereas biogenic polyamines bind to major and minor grooves as well as to phosphate groups. Weaker interaction with DNA was observed for analogues with respect to biogenic polyamines, with K(333) = 1.90 (+/-0.5) x 10(4) M(-1), K(BE-333) = 6.4 (+/-1.7) x 10(4) M(-1), K(BE-3333) = 4.7 (+/-1.4) x 10(4) M(-1) compared to K(Spm) = 2.3 (+/-1.1) x 10(5) M(-1), K(Spd) = 1.4 (+/-0.6) x 10(5) M(-1), and K(Put) = 1.02 (+/-0.5) x 10(5) M(-1). A partial B- to A-DNA transition was also provoked by analogues. These data suggest distinct differences in the binding of natural and synthetic polyamines with DNA.

  15. Effect of the mixtures of squid ink tyrosinase and tannic acid on properties of sardine surimi gel.

    PubMed

    Vate, Naveen Kumar; Benjakul, Soottawat

    2016-01-01

    Effect of the mixture of squid ink tyrosinase (SIT) at 300 and 500 U/g protein and tannic acid (TA) at 0.5 and 1 % (based on protein) with different reaction times (90 and 180 min) on gel properties of sardine surimi was investigated. Surimi gel incorporated with mixture of SIT (500 U/g protein) and 1 % TA with a reaction time of 90 min had the highest breaking force and deformation (p < 0.05), in which the increases by 29.3 % and 11.9 % were observed, in comparison with the control. However, gels added with SIT/TA mixture had the lower whiteness, compared to the control (p < 0.05). Gel added with SIT/TA mixture showed more compact and finer network with higher connectivity of strands, compared to the control. This was coincidental with decreased expressible moisture content. Based on sensory evaluation, the highest overall likeness score was found in gel added with the mixture of SIT (500 U/g protein) and 1 % TA (p < 0.05). Therefore the mixture of tyrosinase from squid ink and tannic acid could be used as additives to improve the properties of surimi gel.

  16. Modification of wheat starch with succinic acid/acetic anhydride and azelaic acid/acetic anhydride mixtures I. Thermophysical and pasting properties.

    PubMed

    Subarić, Drago; Ačkar, Durđica; Babić, Jurislav; Sakač, Nikola; Jozinović, Antun

    2014-10-01

    The aim of this research was to investigate the influence of modification with succinic acid/acetic anhydride and azelaic acid/acetic anhydride mixtures on thermophysical and pasting properties of wheat starch. Starch was isolated from two wheat varieties and modified with mixtures of succinic acid and acetic anhydride, and azelaic acid and acetic anhydride in 4, 6 and 8 % (w/w). Thermophysical, pasting properties, swelling power, solubility and amylose content of modified starches were determined. The results showed that modifications with mixtures of afore mentioned dicarboxylic acids with acetic anhydride decreased gelatinisation and pasting temperatures. Gelatinisation enthalpy of Golubica starch increased, while of Srpanjka starch decreased by modifications. Retrogradation after 7 and 14 day-storage at 4 °C decreased after modifications of both starches. Maximum, hot and cold paste viscosity of both starches increased, while stability during shearing at high temperatures decreased. % setback of starches modified with azelaic acid/acetic anhydride mixture decreased. Swelling power and solubility of both starches increased by both modifications.

  17. Advanced stability indicating chemometric methods for quantitation of amlodipine and atorvastatin in their quinary mixture with acidic degradation products

    NASA Astrophysics Data System (ADS)

    Darwish, Hany W.; Hassan, Said A.; Salem, Maissa Y.; El-Zeany, Badr A.

    2016-02-01

    Two advanced, accurate and precise chemometric methods are developed for the simultaneous determination of amlodipine besylate (AML) and atorvastatin calcium (ATV) in the presence of their acidic degradation products in tablet dosage forms. The first method was Partial Least Squares (PLS-1) and the second was Artificial Neural Networks (ANN). PLS was compared to ANN models with and without variable selection procedure (genetic algorithm (GA)). For proper analysis, a 5-factor 5-level experimental design was established resulting in 25 mixtures containing different ratios of the interfering species. Fifteen mixtures were used as calibration set and the other ten mixtures were used as validation set to validate the prediction ability of the suggested models. The proposed methods were successfully applied to the analysis of pharmaceutical tablets containing AML and ATV. The methods indicated the ability of the mentioned models to solve the highly overlapped spectra of the quinary mixture, yet using inexpensive and easy to handle instruments like the UV-VIS spectrophotometer.

  18. Synthesis and characterization of poly lactic acid and multiwall carbon nano-tubes mixtures

    NASA Astrophysics Data System (ADS)

    Kumar LG, Santhosh; del A. Cardona, Rocío; Berríos-Soto, Melvin; Santiago-Avilés, Jorge J.

    2011-10-01

    The motivation for this study is to reproduce processing conditions which lead to the formation of photo or photoinduced thermal actuation, combined with inexpensive, environmentally friendly (easily degradable) materials. Commercially available polymer, poly lactic acid (PLA), was used in our studies. PLA is a well know biodegradable polymer naturally obtained from corn. PLA was received as a solid resin in pellet form and dissolved in 1:3 acetone/chloroform solutions, to achieve the proper electrospinning kinematic viscosity. Once in the liquid phase, the material was mixed with commercially available multi-walled carbon nanotubes (MWCNTs) at varying concentrations and dispersed by severe sonication. The mixtures was electrospun at room temperature using a home built electrospinning apparatus capable of depositing randomly oriented fiber mats or oriented fibers onto different substrates, ranging from oxidized silicon wafers, alumina squares or glass microscope slides. The fibers diameters and lengths are statistically distributed following a log-normal distribution and the mean and dispersion are controlled by spinning parameters. Once the fibers were electrospun, they were compositionally, morphologically and structurally characterized by thermal and gravimetric analysis (TGA/DTA), rheology, imaging using a focused Ion Beam Scanning Electron Microscope (IBSEM), and IR /Raman methodologies. These studies can be used to explore PLA-MWCNTs mixtures suitability in applications such as super-capacitor technology, which would enable us to pursue further research in this field, while focusing on improving the electro spinning conditions so as to be able to better anticipate fiber morphology to generate a consistent regime of fibers.

  19. ETHANOL, ACETIC ACID, AND WATER ADSORPTION FROM BINARY AND TERNARY LIQUID MIXTURES ON HIGH-SILICA ZEOLITES

    EPA Science Inventory

    Adsorption isotherms were measured for ethanol, acetic acid, and water adsorbed on high-silica ZSM-5 zeolite powder from binary and ternary liquid mixtures at room temperature. Ethanol and water adsorption on two high-silica ZSM-5 zeolites with different aluminum contents and a h...

  20. Environmentally Realistic Mixtures of the Five Regulated Haloacetic Acids Exhibit Concentration-Dependent Departures from Dose Additivity

    EPA Science Inventory

    Disinfection of water decreases waterborne disease. Disinfection byproducts (DBPs) are formed by the reaction of oxidizing disinfectants with inorganic and organic materials in the source water. The U.S. EPA regulates five haloacetic acid (HAA) DBPs as a mixture. The objective ...

  1. Bacterial flora of skin of processed broiler chickens after successive washings in mixtures of potassium hydroxide and lauric acid

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Changes in the size of the populations of different groups of bacteria in the normal flora of the skin of processed broilers were examined after each of five consecutive washings with mixtures of potassium hydroxide (KOH) and lauric acid (LA). Skin from commercially processed broiler carcasses was ...

  2. Determining a Robust D-Optimal Design for Testing for Departure from Additivity in a Mixture of Four Perfluoroalkyl Acids.

    EPA Science Inventory

    Our objective is to determine an optimal experimental design for a mixture of perfluoroalkyl acids (PFAAs) that is robust to the assumption of additivity. PFAAs are widely used in consumer products and industrial applications. The presence and persistence of PFAAs, especially in ...

  3. Integrated phospholipidomics and transcriptomics analysis of Saccharomyces cerevisiae with enhanced tolerance to a mixture of acetic acid, furfural, and phenol

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A mixture of acetic acid, furfural and phenol (AFP), three representative lignocellulose derived inhibitors, significantly inhibited the growth and bioethanol production of Saccharomyces cerevisiae. In order to uncover mechanisms behind the enhanced tolerance of an inhibitor-tolerant S.cerevisiae s...

  4. Adsorption from n-heptane/benzene liquid mixture on acid leached bentonite powders

    NASA Astrophysics Data System (ADS)

    Sarıkaya, Yüksel; Baykal, Mehmet; Önal, Müşerref; Yener, Nilgün

    2013-10-01

    In this study, adsorption excess isotherms of n-heptane/benzene liquid mixture on hydrochloric acid leached bentonite powders were determined. Adsorptions were conducted at 25 °C for 48 h. Experimental results were evaluated with both Schay-Nagy (SN) and Everett (E) methods. Specific surface areas (SSN and SE) of the powders were calculated regarding monolayer adsorption capacity of the preferentially adsorbed benzene. Adsorption equilibrium constants (K ≫ 1) were obtained by the E-method. The SE and SSN values are closed to each other. SE-values were found much lower than the corresponding Brunauer, Emmett and Teller (BET)-values. This difference was discussed with respect to the interaction of adsorbed molecules with solid surface, their collision diameter, molar cross sectional surface area and orientation in dense monolayer. Even the maximum for the SE was not associated with the maxima for K and nanopore volume (V), their values changed approximately parallel to each other with respect to the HCl% by the leaching.

  5. Multi-generational xenoestrogenic effects of Perfluoroalkyl acids (PFAAs) mixture on Oryzias latipes using a flow-through exposure system.

    PubMed

    Lee, Jin Wuk; Lee, Jae-Woo; Shin, Yu-Jin; Kim, Ji-Eun; Ryu, Tae-Kwon; Ryu, Jisung; Lee, Jaean; Kim, Pilje; Choi, Kyunghee; Park, Kyunghwa

    2017-02-01

    To elucidate the multi-generational estrogenic potential of Perfluoroalkyl acids (PFAAs) mixture, vitellogenin (VTG) expression, growth indices, histological alteration, fecundity, hatching rate, larval survival rate, and sex ratio of Japanese medaka (Oryzias latipes) were investigated by exposing the fish to a mixture of perfluorooctane sulfonate (PFOS), perfluroroctanoic acid (PFOA), perfluorobutane sulfonate (PFBS), and perfluorononanoic acid (PFNA) for three generations (238 days). Mixture composition is in the ratio of 1:1:1:1. In addition, whole body burden for each PFAA was analyzed. According to the results, concentrated levels of the PFAAs in both F1 and F2 generation O. latipes were ordered PFOS > PFNA > PFOA > PFBS at both low concentration (0.5 μg/L) and high concentration (5 μg/L), whereas a significant difference in whole body burden based on sex or generation was not detected. Significant induction of VTG expression in F2 and the decline of the gonad somatic index (GSI) in F1 were observed following PFAAs mixture exposure (p < 0.05, one-way ANOVA). Furthermore, suppression level of reproduction rate relative to the control increased as generation was transferred to the next in response to PFAAs mixture or 17 β-estradiol exposure, with the inhibition of hatchability observed in the F1 generation. The PFAA high concentration caused significant alteration of F1 generation sex ratio, suggesting the adverse effect of PFAA in population level (Chi-square test, P > 0.05). Overall, this study demonstrated that PFAA mixture could have the potential of multi-generational endocrine disruptors in O. latipes.

  6. Polyamine metabolism in Menkes kinky hair disease.

    PubMed

    Rennert, O M; Chan, W Y; Hidalgo, H; Cushing, W; Griesmann, G

    1980-05-09

    Clinical investigations of the urinary excretion of putrescine and the polyamines spermidine and spermine in a patient with Menkes kinky hair disease are reported. This disorder, characterized by intra- and extracellular copper deficiency, is associated with significant depression of diamine oxidase and monoamine oxidase activity. Urinary excretion of diamine and polyamines, monitored over a 2-month interval in a 4-month old patient with Menkes kinky hair disease, documented a 3- to 10-fold increase in the excretion of free putrescine, spermidine and spermine as well as the conjugated derivatives of putrescine and spermidine. These observations suggest that abnormalities in diamine and polyamine concentration occur in disease states in which the metabolic transformation of these compounds is impaired.

  7. Mixture toxicity of the antiviral drug Tamiflu((R)) (oseltamivir ethylester) and its active metabolite oseltamivir acid.

    PubMed

    Escher, Beate I; Bramaz, Nadine; Lienert, Judit; Neuwoehner, Judith; Straub, Jürg Oliver

    2010-02-18

    Tamiflu (oseltamivir ethylester) is an antiviral agent for the treatment of influenza A and B. The pro-drug Tamiflu is converted in the human body to the pharmacologically active metabolite, oseltamivir acid, with a yield of 75%. Oseltamivir acid is indirectly photodegradable and slowly biodegradable in sewage works and sediment/water systems. A previous environmental risk assessment has concluded that there is no bioaccumulation potential of either of the compounds. However, little was known about the ecotoxicity of the metabolite. Ester hydrolysis typically reduces the hydrophobicity and thus the toxicity of a compound. In this case, a zwitterionic, but overall neutral species is formed from the charged parent compound. If the speciation and predicted partitioning into biological membranes is considered, the metabolite may have a relevant contribution to the overall toxicity. These theoretical considerations triggered a study to investigate the toxicity of oseltamivir acid (OA), alone and in binary mixtures with its parent compound oseltamivir ethylester (OE). OE and OA were found to be baseline toxicants in the bioluminescence inhibition test with Vibrio fischeri. Their mixture effect lay between predictions for concentration addition and independent action for the mixture ratio excreted in urine and nine additional mixture ratios of OE and OA. In contrast, OE was an order of magnitude more toxic than OA towards algae, with a more pronounced effect when the direct inhibition of photosystem II was used as toxicity endpoint opposed to the 24h growth rate endpoint. The binary mixtures in this assay yielded experimental mixture effects that agreed with predictions for independent action. This is consistent with the finding that OE exhibits slightly enhanced toxicity, while OA acts as baseline toxicant. Therefore, with respect to mixture classification, the two compounds can be considered as acting according to different modes of toxic action, although there are

  8. Experimental determination and prediction of (solid+liquid) phase equilibria for binary mixtures of heavy alkanes and fatty acids

    NASA Astrophysics Data System (ADS)

    Benziane, Mokhtar; Khimeche, Kamel; Dahmani, Abdellah; Nezar, Sawsen; Trache, Djalal

    2012-06-01

    Solid-liquid equilibria for three binary mixtures, n-Eicosane (1) + Lauric acid (2), n-Tetracosane (1) + Stearic acid (2), and n-Octacosane (1) + Palmitic acid (2), were measured using a differential scanning calorimeter. Simple eutectic behaviour was observed for these systems. The experimental results were correlated by means of the modified UNIFAC (Larsen and Gmehling versions), UNIQUAC and ideal models. The root-mean-square deviations of the solubility temperatures for all measured data vary from 0.26 to 3.15 K and depend on the particular model used. The best solubility correlation was obtained with the UNIQUAC model.

  9. Recovery of fatty acid from a solvated hydrocarbon mixture applicable to the Beaver-Herter solvent extraction process

    SciTech Connect

    Beaver, W.H.; Turpin, J.L.; Babcock, R.E.

    1985-01-01

    The Herter process is a patented solvent extraction enhanced oil recovery process. This process utilizes fatty acid as a solvent to mix with and reduce the viscosity of a heavy reservoir oil or a tar sand. This method differs from other solvent extraction oil recovery methods in that the recovery of the fatty acid solvent for further use, rather than the initial expense of the solvent, is the prime economic consideration. The fatty acid is recovered by saponification of the solvated oil mixture using an aqueous base, followed by migration of the resulting soap into the aqueous phase, and then desaponification of the aqueous phase.

  10. Fed-batch fermentation for enhanced lactic acid production from glucose/xylose mixture without carbon catabolite repression.

    PubMed

    Abdel-Rahman, Mohamed Ali; Xiao, Yaotian; Tashiro, Yukihiro; Wang, Ying; Zendo, Takeshi; Sakai, Kenji; Sonomoto, Kenji

    2015-02-01

    There has been tremendous growth in the production of optically pure l-lactic acid from lignocellulose-derived sugars. In this study, Enterococcus mundtii QU 25 was used to ferment a glucose/xylose mixture to l-lactic acid. Maintenance of the xylose concentration at greater than 10 g/L achieved homo-lactic acid fermentation and reduced the formation of byproducts. Furthermore, carbon catabolite repression (CCR) was avoided by maintaining the glucose concentration below 25 g/L; therefore, initial concentrations of 25 g/L glucose and 50 g/L xylose were selected. Supplementation with 5 g/L yeast extract enhanced the maximum xylose consumption rate and consequently increased lactic acid production and productivity. Finally, a 129 g/L lactic acid without byproducts was obtained with a maximum lactic acid productivity of 5.60 g/(L·h) in fed-batch fermentation with feeding a glucose/xylose mixture using ammonium hydroxide as the neutralizing agent. These results indicate a potential for lactic acid production from glucose and xylose as the main components of lignocellulosic biomasses.

  11. Polyamines and hair: a couple in search of perfection.

    PubMed

    Ramot, Yuval; Pietilä, Marko; Giuliani, Giammaria; Rinaldi, Fabio; Alhonen, Leena; Paus, Ralf

    2010-09-01

    Polyamines (spermidine, putrescine and spermine) are multifunctional cationic amines that are indispensable for cellular proliferation; of key significance in the growth of rapidly regenerating tissues and tumors. Given that the hair follicle (HF) is one of the most highly proliferative organs in mammalian biology, it is not surprising that polyamines are crucial to HF growth. Indeed, growing (anagen) HFs show the highest activity of ornithine decarboxylase (ODC), the rate-limiting enzyme of polyamine biosynthesis, while inhibition of ODC, using eflornithine, results in a decreased rate of excessive facial hair growth in vivo and inhibits human scalp hair growth in organ culture. In sheep, manipulation of dietary intake of polyamines also results in altered wool growth. Polyamine-containing nutraceuticals have therefore been proposed as promoters of human hair growth. Recent progress in polyamine research, coupled with renewed interest in the role of polyamines in skin biology, encourages one to revisit their potential roles in HF biology and highlights the need for a systematic evaluation of their mechanisms of action and clinical applications in the treatment of hair disorders. The present viewpoint essay outlines the key frontiers in polyamine-related hair research and defines the major open questions. Moreover, it argues that a renaissance in polyamine research in hair biology, well beyond the inhibition of ODC activity in hirsutism therapy, is important for the development of novel therapeutic strategies for the manipulation of human hair growth. Such targets could include the manipulation of polyamine biosynthesis and the topical administration of selected polyamines, such as spermidine.

  12. Synthesis of formamide and isocyanic acid after ion irradiation of frozen gas mixtures

    NASA Astrophysics Data System (ADS)

    Kaňuchová, Z.; Urso, R. G.; Baratta, G. A.; Brucato, J. R.; Palumbo, M. E.; Strazzulla, G.

    2016-01-01

    Context. Formamide (NH2HCO) and isocyanic acid (HNCO) have been observed as gaseous species in several astronomical environments such as cometary comae and pre- and proto-stellar objects. A debate is open on the formation route of those molecules, in particular if they are formed by chemical reactions in the gas phase and/or on grains. In this latter case it is relevant to understand if the formation occurs through surface reactions or is induced by energetic processing. Aims: We present arguments that support the formation of formamide in the solid phase by cosmic-ion-induced energetic processing of ices present as mantles of interstellar grains and on comets. Formamides, along with other molecules, are expelled in the gas phase when the physical parameters are appropriate to induce the desorption of ices. Methods: We have performed several laboratory experiments in which ice mixtures (H2O:CH4:N2, H2O:CH4:NH3, and CH3OH:N2) were bombarded with energetic (30-200 keV) ions (H+ or He+). FTIR spectroscopy was performed before, during, and after ion bombardment. In particular, the formation of HNCO and NH2HCO was measured quantiatively. Results: Energetic processing of ice can quantitatively reproduce the amount of NH2HCO observed in cometary comae and in many circumstellar regions. HNCO is also formed, but additional formation mechanisms are requested to quantitatively account for the astronomical observations. Conclusions: We suggest that energetic processing of ices in the pre- and proto-stellar regions and in comets is the main mechanism to produce formamide, which, once it is released in the gas phase because of desorption of ices, is observed in the gas phase in these astrophysical environments.

  13. Some polyphenols inhibit the formation of pentyl radical and octanoic acid radical in the reaction mixture of linoleic acid hydroperoxide with ferrous ions.

    PubMed Central

    Iwahashi, H

    2000-01-01

    Effects of some polyphenols and their related compounds (chlorogenic acid, caffeic acid, quinic acid, ferulic acid, gallic acid, D-(+)-catechin, D-(-)-catechin, 4-hydroxy-3-methoxybenzoic acid, salicylic acid, L-dopa, dopamine, L-adrenaline, L-noradrenaline, o-dihydroxybenzene, m-dihydroxybenzene, and p-dihydroxybenzene) on the formation of 13-hydroperoxide octadecadienoic (13-HPODE) acid-derived radicals (pentyl radical and octanoic acid radical) were examined. The ESR spin trapping showed that chlorogenic acid, caffeic acid, gallic acid, D-(+)-catechin, D-(-)-catechin, L-dopa, dopamine, L-adrenaline, L-noradrenaline, and o-dihydroxybenzene inhibited the overall formation of 13-HPODE acid-derived radicals in the reaction mixture of 13-HPODE with ferrous ions. The ESR peak heights of alpha-(4-pyridyl-1-oxide)-N-tert-butylnitrone (4-POBN)/13-HPODE-derived radical adducts decreased to 46+/-4% (chlorogenic acid), 54+/-2% (caffeic acid), 49+/-2% (gallic acid), 55+/-1% [D-(+)-catechin], 60+/-3% [D-(-)-catechin], 42+/-1% (L-dopa), 30+/-2% (dopamine), 49+/-2% (L-adrenaline), 24+/-2% (L-noradrenaline), and 54+/-5% (o-dihydroxybenzene) of the control, respectively. The high performance liquid chromatography-electron spin resonance (HPLC-ESR) and high performance liquid chromatography-electron spin resonance-mass spectrometries (HPLC-ESR-MS) showed that caffeic acid inhibited the formation of octanoic acid radical and pentyl radical to 42+/-2% and 52+/-7% of the control, respectively. On the other hand, the polyphenols and their related compounds had few inhibitory effects on the radical formation in the presence of EDTA. Visible absorbance measurement revealed that all the polyphenols exhibiting the inhibitory effect chelate ferrous ions. Above results indicated that the chelation of ferrous ion is essential to the inhibitory effects of the polyphenols. PMID:10677343

  14. Effects of a combination of hinokitiol (β-thujaplicin) and an organic acid mixture on ruminal fermentation in heifers fed a high-grain diet.

    PubMed

    Ishii, Junichiro; Omura, Hiroshi; Mitsui, Tadao; Eguchi, Norichika; Ueno, Takashi; Goto, Hisaya; Ito, Hiroshi

    2012-01-01

    This study evaluated the effects of hinokitiol (a natural antibacterial compound extracted from Thujopsis dolabrata var. hondai) and an organic acid mixture (citrate content 50%) on ruminal fermentation. Antibacterial properties were examined by measuring minimal inhibitory concentration. Hinokitiol at 1.56µg/mL or an organic acid mixture at 1600µg/mL inhibited Streptococcus bovis growth. The combination of 0.78µg/mL hinokitiol and 200µg/mL of an organic acid mixture also inhibited S. bovis growth. Both hinokitiol and the hinokitiol and an organic acid mixture combination showed strong antibacterial properties on Gram-positive bacteria such as S. bovis, but relatively weak antibacterial activities on Gram-negative bacteria such as Megasphaera elsdenii. Three ruminally cannulated heifers were fed a bloat-producing diet containing barley, pelleted alfalfa meal, soybean meal and salt without long-cut roughage to investigate the ruminal characteristics in vivo. Feeding to heifers a bloat-producing diet containing 7.8mg/kg hinokitiol and 0.2% of an organic acid mixture significantly decreased the increase in stable ingesta volume. Hinokitiol or an organic acid mixture did not affect ruminal volatile fatty acids, protozoa and bacteria. These results suggest that a combination of hinokitiol and an organic acid mixture might reduce frothy bloat in cattle fed high-grain diets.

  15. Enhanced Photocatalytic Degradation of Salicylic Acid in Water-ethanol Mixtures from Titanium Dioxide Grafted with Hexadecyltrichlorosilane

    NASA Astrophysics Data System (ADS)

    Kassir, Mounir; Roques-Carmes, Thibault; Assaker, Karine; Hamieh, Tayssir; Razafitianamaharavo, Angelina; Toufaily, Joumana; Villiéras, Frédéric

    The aim of this paper is to study the effect of the chemical modification on the photocatalytic properties of TiO2. The TiO2 Degussa-P25 nanoparticles are chemically modified using the hydrophobic organosilane hexadecyltrichlorosilane (HTS). The samples are employed as catalysts for salicylic acid photocatalytic oxidation in water-ethanol mixtures. The kinetics of salicylic acid photodegradation is investigated as a function of ethanol content in water-ethanol mixtures and initial HTS concentrations. The results indicate that the HTS groups are not degraded during the photocatalytic process. The TiO2 grafted by HTS is more efficient than bare TiO2 for the photodegradation process in presence of ethanol. The photodegradation process follows first order kinetics and the apparent rate constant increases linearly with the initial HTS concentration (amount of HTS grafted).

  16. Finding of primitive polyamine toxins in the venom of a joro spider, Nephila clavata.

    PubMed

    Chiba, T; Akizawa, T; Matsukawa, M; Pan-Hou, H; Yoshioka, M

    1994-09-01

    A series of joro spider toxins, novel polyamines sharing a common moiety of 2,4-dihydroxyphenylacetyl cadaverine, have been identified using various bioassays, such as inhibition of a glutamatergic transmission and insecticidal activity. In this paper, we tried to chemically find still unknown polyamine toxins in the venom of a joro spider, N. clavata, by several analytical methods based on the characteristics of the common moiety. An aqueous extract from 3000 venoms was separated by preparative high performance liquid chromatography (HPLC). The polyamine toxins were detected by monitoring the fluorescence produced in an on-line reaction of o-phthalaldehyde with amino groups and UV absorption of the phenol group. Two compounds in minute quantity were purified and analyzed by gas-liquid chromatography (GC) and HPLC, which we specifically developed for the simultaneous determination of amino acids and polyamines of the toxins. Judging from the constituents of the hydrolysate by GC and HPLC and the molecular weights determined by fast atom bombardment mass spectrometry, the two compounds were estimated to be N-(2,4-dihydroxyphenylacetyl-L-asparaginyl)-N'- (3-aminopropyl-beta-alanyl) cadaverine and N-(4-hydroxyphenylacetyl-L-asparaginyl)-N'-(3-aminopropyl-beta-ala nyl) cadaverine. These compounds were small in content and molecular weight compared with hitherto known toxins. Both were presumed to be biochemically primitive toxins and were named spidamine and joramine, respectively.

  17. A Polyamine Twist on Hedgehog Signaling.

    PubMed

    Zhao, Xuesong; Segal, Rosalind A

    2015-10-12

    The Hedgehog pathway plays important roles in embryonic development and oncogenesis, but how it affects metabolism is less clear. D'Amico et al. (2015) now demonstrate that the Hedgehog pathway regulates translation of ornithine decarboxylase, thereby enhancing polyamine biosynthesis and cell proliferation in neural precursor cells and in brain tumors.

  18. Endogenous polyamine function—the RNA perspective

    PubMed Central

    Lightfoot, Helen L.; Hall, Jonathan

    2014-01-01

    Recent progress with techniques for monitoring RNA structure in cells such as ‘DMS-Seq’ and ‘Structure-Seq’ suggests that a new era of RNA structure-function exploration is on the horizon. This will also include systematic investigation of the factors required for the structural integrity of RNA. In this context, much evidence accumulated over 50 years suggests that polyamines play important roles as modulators of RNA structure. Here, we summarize and discuss recent literature relating to the roles of these small endogenous molecules in RNA function. We have included studies directed at understanding the binding interactions of polyamines with polynucleotides, tRNA, rRNA, mRNA and ribozymes using chemical, biochemical and spectroscopic tools. In brief, polyamines bind RNA in a sequence-selective fashion and induce changes in RNA structure in context-dependent manners. In some cases the functional consequences of these interactions have been observed in cells. Most notably, polyamine-mediated effects on RNA are frequently distinct from those of divalent cations (i.e. Mg2+) confirming their roles as independent molecular entities which help drive RNA-mediated processes. PMID:25232095

  19. Lichenysin-geminal amino acid-based surfactants: Synergistic action of an unconventional antimicrobial mixture.

    PubMed

    Coronel-León, Jonathan; Pinazo, Aurora; Pérez, Lourdes; Espuny, Mª José; Marqués, Ana Mª; Manresa, Angeles

    2017-01-01

    Recently it has been demonstrated that catanionic mixtures of oppositely charged surfactants have improved physicochemical-biological properties compared to the individual components. Isotherms of mixtures of an anionic biosurfactant (lichenysin) and a cationic aminoacid surfactant (C3(LA)2) indicate a strong interaction suggesting the formation of a new "pseudo-surfactant". The antimicrobial properties of the mixture lichenysin and C3(LA)2 M80:20, indicate a synergistic effect of the components. The mechanism of action on the bacterial envelope was assessed by flow cytometry and Transmission Electron Microscopy.

  20. Leishmania major lacking arginase are auxotrophic for polyamines but retain infectivity to susceptible BALB/c mice

    PubMed Central

    Reguera, Rosa M.; Balaña-Fouce, Rafael; Showalter, Melissa; Hickerson, Suzanne; Beverley, Stephen M.

    2009-01-01

    Polyamines are essential metabolites in eukaryotes participating in a variety of proliferative processes, and in trypanosomatid protozoa play an additional role in the synthesis of the critical thiol trypanothione. Whereas the polyamine biosynthesis arising from L-ornithine has been well studied in protozoa, the metabolic origin(s) of L-ornithine have received less attention. Arginase (EC 3.5.3.1) catalyzes the enzymatic hydrolysis of L-arginine to L-ornithine and urea, and we tested the role of arginase in polyamine synthesis by the generation of an arg− knockout in Leishmania major by double targeted gene replacement. This mutant lacked arginase activity and required the nutritional provision of polyamines or L-ornithine for growth. A complemented line (arg−/+ARG) expressing arginase from a multicopy expression vector showed 30-fold elevation of arginase activity, similar polyamine and ornithine levels as the wild-type, and resistance to the inhibitors α-difluoromethylornithine (DFMO) and Nω-hydroxy-L-arginine (NOHA). This established that arginase is the major route of polyamine synthesis in promastigotes cultured in vitro. The arg− parasites retained the ability to differentiate normally to the infective metacyclic stage, and were able to induce progressive disease following inoculation into susceptible BALB/c mice, albeit less efficiently than WT parasites. These data suggest that the infective amastigote form of Leishmania, which normally resides within an acidified parasitophorous vacuole, can survive in vivo through salvage of host polyamines and/or other molecules, aided by the tendency of acidic compartments to concentrate basic metabolites. This may thus contribute to the relative resistance of Leishmania to ornithine decarboxylase (ODC) inhibitors. The availability of infective, viable, arginase-deficient parasites should prove useful in dissecting the role of L-arginine metabolism in both pro- and anti-parasitic responses involving host nitric

  1. Nonequimolar Mixture of Organic Acids and Bases: An Exception to the Rule of Thumb for Salt or Cocrystal.

    PubMed

    Pratik, Saied Md; Datta, Ayan

    2016-08-04

    Formation of salt and/or cocrystal from organic acid-base mixtures has significant consequences in the pharmaceutical industry and its related intellectual property rights (IPR). On the basis of calculations using periodic dispersion corrected DFT (DFT-D2) on formic acid-pyridine adduct, we have demonstrated that an equimolar stoichiometric ratio (1:1) exists as a neutral cocrystal. On the other hand, the nonequimolar stoichiometry (4:1) readily forms an ionic salt. While the former result is in agreement with the ΔpKa rule between the base and the acid, the latter is not. Calculations reveal that, within the equimolar manifold (n:n; n = 1-4), the mixture exists as a hydrogen bonded complex in a cocrystal-like environment. However, the nonequimolar mixture in a ratio of 5:1 and above readily forms salt-like structures. Because of the cooperative nature of hydrogen bonding, the strength of the O-H···N hydrogen bond increases and eventually transforms into O(-)···H-N(+) (complete proton transfer) as the ratio of formic acid increases and forms salt as experimentally observed. Clearly, an enhanced polarization of formic acid on aggregation increases its acidity and, hence, facilitates its transfer to pyridine. Motion of the proton from formic acid to pyridine is shown to follow a relay mechanism wherein the proton that is far away from pyridine is ionized and is subsequently transferred to pyridine via hopping across the neutral formic acid molecules (Grotthuss type pathway). The dynamic nature of protons in the condensed phase is also evident for cocrystals as the barrier of intramolecular proton migration in formic acid (leading to tautomerism), ΔH(⧧)tautomer = 17.1 kcal/mol in the presence of pyridine is half of that in free formic acid (cf. ΔH(⧧)tautomer = 34.2 kcal/mol). We show that an acid-base reaction can be altered in the solid state to selectively form a cocrystal or salt depending on the strength and nature of aggregation.

  2. Study of polydimethylsiloxane/aromatic polyamide laminated membranes for separation of acetic acid/water mixtures by pervaporation process

    SciTech Connect

    Deng, S.; Sourirajan, S.; Matsuura, T. )

    1994-06-01

    Separation of acetic acid/water mixtures by pervaporation was attempted over a range of compositions using polydimethylsiloxane (PDMS), aromatic polyamide (PA), and laminated polydimethylsiloxane-aromatic polyamide membranes. PDMS membranes are hydrophobic and acetic acid selective, whereas PA membranes are hydrophilic and water selective. When PDMS and PA membranes were laminated, with PDMS on the top side and in contact with the feed, water selectivity of the bottom PA membrane was intensified. On the other hand, when the PA membrane was on the top side and in contact with the feed, the selectivity was lowered. 10 refs., 4 figs.

  3. Polyamines function in stress tolerance: from synthesis to regulation

    PubMed Central

    Liu, Ji-Hong; Wang, Wei; Wu, Hao; Gong, Xiaoqing; Moriguchi, Takaya

    2015-01-01

    Plants are challenged by a variety of biotic or abiotic stresses, which can affect their growth and development, productivity, and geographic distribution. In order to survive adverse environmental conditions, plants have evolved various adaptive strategies, among which is the accumulation of metabolites that play protective roles. A well-established example of the metabolites that are involved in stress responses, or stress tolerance, is the low-molecular-weight aliphatic polyamines, including putrescine, spermidine, and spermine. The critical role of polyamines in stress tolerance is suggested by several lines of evidence: firstly, the transcript levels of polyamine biosynthetic genes, as well as the activities of the corresponding enzymes, are induced by stresses; secondly, elevation of endogenous polyamine levels by exogenous supply of polyamines, or overexpression of polyamine biosynthetic genes, results in enhanced stress tolerance; and thirdly, a reduction of endogenous polyamines is accompanied by compromised stress tolerance. A number of studies have demonstrated that polyamines function in stress tolerance largely by modulating the homeostasis of reactive oxygen species (ROS) due to their direct, or indirect, roles in regulating antioxidant systems or suppressing ROS production. The transcriptional regulation of polyamine synthesis by transcription factors is also reviewed here. Meanwhile, future perspectives on polyamine research are also suggested. PMID:26528300

  4. The mechanisms by which polyamines accelerate tumor spread.

    PubMed

    Soda, Kuniyasu

    2011-10-11

    Increased polyamine concentrations in the blood and urine of cancer patients reflect the enhanced levels of polyamine synthesis in cancer tissues arising from increased activity of enzymes responsible for polyamine synthesis. In addition to their de novo polyamine synthesis, cells can take up polyamines from extracellular sources, such as cancer tissues, food, and intestinal microbiota. Because polyamines are indispensable for cell growth, increased polyamine availability enhances cell growth. However, the malignant potential of cancer is determined by its capability to invade to surrounding tissues and metastasize to distant organs. The mechanisms by which increased polyamine levels enhance the malignant potential of cancer cells and decrease anti-tumor immunity are reviewed. Cancer cells with a greater capability to synthesize polyamines are associated with increased production of proteinases, such as serine proteinase, matrix metalloproteinases, cathepsins, and plasminogen activator, which can degrade surrounding tissues. Although cancer tissues produce vascular growth factors, their deregulated growth induces hypoxia, which in turn enhances polyamine uptake by cancer cells to further augment cell migration and suppress CD44 expression. Increased polyamine uptake by immune cells also results in reduced cytokine production needed for anti-tumor activities and decreases expression of adhesion molecules involved in anti-tumor immunity, such as CD11a and CD56. Immune cells in an environment with increased polyamine levels lose anti-tumor immune functions, such as lymphokine activated killer activities. Recent investigations revealed that increased polyamine availability enhances the capability of cancer cells to invade and metastasize to new tissues while diminishing immune cells' anti-tumor immune functions.

  5. The selective conversion of glutamic acid in amino acid mixtures using glutamate decarboxylase--a means of separating amino acids for synthesizing biobased chemicals.

    PubMed

    Teng, Yinglai; Scott, Elinor L; Sanders, Johan P M

    2014-01-01

    Amino acids (AAs) derived from hydrolysis of protein rest streams are interesting feedstocks for the chemical industry due to their functionality. However, separation of AAs is required before they can be used for further applications. Electrodialysis may be applied to separate AAs, but its efficiency is limited when separating AAs with similar isoelectric points. To aid the separation, specific conversion of an AA to a useful product with different charge behavior to the remaining compounds is desired. Here the separation of L-aspartic acid (Asp) and L-glutamic acid (Glu) was studied. L-Glutamate α-decarboxylase (GAD, Type I, EC 4.1.1.15) was applied to specifically convert Glu into γ-aminobutyric acid (GABA). GABA has a different charge behavior from Asp therefore allowing a potential separation by electrodialysis. Competitive inhibition and reduced operational stability caused by Asp could be eliminated by maintaining a sufficiently high concentration of Glu. Immobilization of GAD does not reduce the enzyme's initial activity. However, the operational stability was slightly reduced. An initial study on the reaction operating in a continuous mode was performed using a column reactor packed with immobilized GAD. As the reaction mixture was only passed once through the reactor, the conversion of Glu was lower than expected. To complete the conversion of Glu, the stream containing Asp and unreacted Glu might be recirculated back to the reactor after GABA has been removed. Overall, the reaction by GAD is specific to Glu and can be applied to aid the electrodialysis separation of Asp and Glu.

  6. Removal of low concentrations of ammonium and humic acid from simulated groundwater by Vermiculite/Palygorskite mixture.

    PubMed

    Zhang, Xiuli; Lv, Guocheng; Liao, Libing; He, Maoqian; Li, Zhaohui; Wang, Mingshan

    2012-08-01

    Contaminants in water are classified into different types based on their physical and chemical properties. Thus, more than one type of sorbents may be needed for their removal. In this article, a combination of vermiculite with palygorskite was studied for their simultaneous removal of ammonium and humic acid from simulated groundwater. Batch results showed that the Langmuir model described ammonium adsorption well with an adsorption capacity of 22 mg/g while the humic acid adsorption data fitted to the linear adsorption better, suggesting different removal mechanisms of these two types of contaminants. Kinetic studies showed an instantaneous removal of ammonium and humic acid. A column packed with mixture of equal volumes of vermiculite and palygorskite could treat 100 pore volumes for ammonium removal at an initial concentration of 10 mg/L and 500 pore volumes for humic acid removal at an initial concentration of 20 mg/L before the effluent concentrations exceeded the standard.

  7. [Molluscacide activity of a mixture of 6-n-alkyl salicylic acids (anacardic acid) and 2 of its complexes with copper (II) and lead (II)].

    PubMed

    Mendes, N M; de Oliveira, A B; Guimarães, J E; Pereira, J P; Katz, N

    1990-01-01

    The molluscicide activity of hexanic extract from Anacardium occidentale L. (cashew) nut shell, of copper (II) complex, of lead (II) complex and anacardic acid has been compared in the laboratory in an attempt to obtain better stability than anacardic acid. This was obtained from the hexanic extract of the cashew nut shell by precipitation with lead (II) hydroxide or cupric sulfate plus sodium hydroxide or (II) cupric hydroxide followed by treatment of lead (II) complex with a diluted solution of sulfuric acid. Ten products of the mixture obtained were tested on adults snails of Biomphalaria glabrata at 1 to 10 ppm. The most active products were copper (II) complex, obtained by cupric sulfate plus sodium hydroxide, and anacardic acid (sodium hydroxide) which presented activity at 4 ppm. The anacardic acid's lead content was above the limits accepted by the United States standards.

  8. Dissolution behavior of co-amorphous amino acid-indomethacin mixtures: The ability of amino acids to stabilize the supersaturated state of indomethacin.

    PubMed

    Ojarinta, Rami; Heikkinen, Aki T; Sievänen, Elina; Laitinen, Riikka

    2017-03-01

    Arginine, phenylalanine, and tryptophan have been previously shown to improve the solid-state stability of amorphous indomethacin. The present study investigates the ability of these amino acids to prolong the supersaturation of indomethacin in both aqueous and biorelevant conditions either when freely in solution or when formulated as co-amorphous mixtures. The co-amorphous amino acid-indomethacin mixtures (molar ratio 1:1) and amorphous indomethacin were prepared by cryomilling. Dissolution and precipitation tests were performed in buffer solutions (pH 5 and 6.5) and in Fed and Fasted State Simulated Intestinal Fluids (FeSSIF and FaSSIF, respectively). Precipitation tests were conducted with the solvent shift method. The supersaturation stability of indomethacin and the precipitation inhibitory effect of amino acids were evaluated by calculating the supersaturation factor and the excipient gain factor, respectively. Biorelevant media exerted a significant effect on indomethacin solubility but had little effect on the supersaturation stability. Arginine had the most significant impact on the dissolution properties of indomethacin, but also phenylalanine and tryptophan stabilized supersaturation in some media when formulated as co-amorphous mixtures with indomethacin. Only arginine stabilized supersaturation without co-amorphization, an effect only observed in media of pH 6.5. The unique behavior of the arginine-indomethacin mixture was further demonstrated by the abrupt formation of a precipitate, when an excess physical mixture of arginine and indomethacin was added to FeSSIF (pH 6.5). The solid-state investigation of this precipitate indicated that it probably consisted of crystalline arginine-indomethacin salt with possibly some residual crystalline starting materials.

  9. Methylmalonic and propionic acidurias: management without or with a few supplements of specific amino acid mixture.

    PubMed

    Touati, G; Valayannopoulos, V; Mention, K; de Lonlay, P; Jouvet, P; Depondt, E; Assoun, M; Souberbielle, J C; Rabier, D; Ogier de Baulny, H; Saudubray, J-M

    2006-01-01

    In a series of 137 patients with methylmalonic acidaemia (MMA) and propionic acidaemia (PA) diagnosed since the early 1970s, we report in more detail 81 patients (51 MMA and 30 PA) diagnosed between 1988 and 2005. In this series, 14% of patients died at initial access revealing the disease before or despite treatment, 18% died later, and the remainder (68%) are still alive. All patients were treated with the same protocol of enteral feeds with a low-protein diet adjusted to individual tolerance, carnitine, antibiotics, and only occasional use of an amino acid (AA) mixture. There was intensive follow-up and monitoring using measurements of urinary urea. Thirty-nine patients with severe forms, followed for more than 3 years, are analysed in particular detail. Of the 17 PA patients, 6 had moderate disability (all neonatal-onset forms), whereas 11 were normal or slightly delayed in their mental development. Four presented with cardiomyopathy, of whom 2 died. Of the 22 MMA patients, 13 presented in the neonatal period, of whom 3 died later, 2 are in renal failure and only 5 are still alive and have a normal or slightly delayed mental development. In the 9 patients with late-onset forms, there were no deaths and all patients but one have normal mental development. Among the 39 patients, only 40% were given an AA supplement at 3 years, and 50% between 6 and 11 years. The actual intake of natural protein was 0.92, 0.78 and 0.77 g/kg per day at 3, 6 and 11 years, respectively, in patients without AA supplementation, whereas it was 0.75, 0.74 and 0.54 g/kg per day in the group who received small quantities of AA (0.4-0.6 g/kg per day). In both groups, feeding disorders were frequent: 55% at 3 years, 35% at 6 years and 12% at 11 years. Many patients were given a food supplement by tube overnight or were even exclusively tube fed: 60% at 3 years, 48% at 6 years and still 27% at 11 years. Growth velocity was near the normal values. Plasma valine and isoleucine were low to very

  10. An equilibrium model for ligand-modified micellar-enhanced ultrafiltration. Selective separation of metal ions using iminoacetic substituted polyamines and a theoretical model for the titration behavior of polyamines

    SciTech Connect

    Dharmawardana, Udeni Rajaratna

    1992-01-01

    This thesis consists of three chapters. Chapter 1, An equilibrium model for ligand-modified micellar-enhanced ultrafiltration, describes a theoretical model and experimental investigations which used the semi-equilibrium-dialysis method with N-n-dodecyl iminodiacetic acid as the ligand. In Chapter 2, Selective separation of metal ions using iminoacetic substituted polyamines, polyamines with a substituted ligand group are synthesized and used in investigating selective separation of copper ions from aqueous solution. In Chapter 3, A theoretical model for the titration behavior of polyamines, a novel approach to explain the titration behavior of polymeric amines based on the binding behavior of counterions is described. The application of this study is to the investigation of inexpensive and efficient methods of industrial waste water treatment.

  11. Molecular dynamics simulations of triflic acid and triflate ion/water mixtures: a proton conducting electrolytic component in fuel cells.

    PubMed

    Sunda, Anurag Prakash; Venkatnathan, Arun

    2011-11-30

    Triflic acid is a functional group of perflourosulfonated polymer electrolyte membranes where the sulfonate group is responsible for proton conduction. However, even at extremely low hydration, triflic acid exists as a triflate ion. In this work, we have developed a force-field for triflic acid and triflate ion by deriving force-field parameters using ab initio calculations and incorporated these parameters with the Optimized Potentials for Liquid Simulations - All Atom (OPLS-AA) force-field. We have employed classical molecular dynamics (MD) simulations with the developed force field to characterize structural and dynamical properties of triflic acid (270-450 K) and triflate ion/water mixtures (300 K). The radial distribution functions (RDFs) show the hydrophobic nature of CF(3) group and presence of strong hydrogen bonding in triflic acid and temperature has an insignificant effect. Results from our MD simulations show that the diffusion of triflic acid increases with temperature. The RDFs from triflate ion/water mixtures shows that increasing hydration causes water molecules to orient around the SO(3)(-) group of triflate ions, solvate the hydronium ions, and other water molecules. The diffusion of triflate ions, hydronium ion, and water molecules shows an increase with hydration. At λ = 1, the diffusion of triflate ion is 30 times lower than the diffusion of triflic acid due to the formation of stable triflate ion-hydronium ion complex. With increasing hydration, water molecules break the stability of triflate ion-hydronium ion complex leading to enhanced diffusion. The RDFs and diffusion coefficients of triflate ions, hydronium ions and water molecules resemble qualitatively the previous findings using per-fluorosulfonated membranes.

  12. A systematic investigation and insight into the formation mechanism of bilayers of fatty acid/soap mixtures in aqueous solutions.

    PubMed

    Xu, Wenlong; Song, Aixin; Dong, Shuli; Chen, Jingfei; Hao, Jingcheng

    2013-10-08

    Vesicles are the most common form of bilayer structures in fatty acid/soap mixtures in aqueous solutions; however, a peculiar bilayer structure called a "planar sheet" was found for the first time in the mixtures. In the past few decades, considerable research has focused on the formation theory of bilayers in fatty acid/soap mixtures. The hydrogen bond theory has been widely accepted by scientists to explain the formation of bilayers. However, except for the hydrogen bond, no other driving forces were proposed systematically. In this work, three kinds of weak interactions were investigated in detail, which could perfectly demonstrate the formation mechanism of bilayer structures in the fatty acid/soap mixtures in aqueous solutions. (i) The influence of hydrophobic interaction was detected by changing the chain length of fatty acid (C(n)H(2n+1)COOH), in which n = 10 to 18, the phase behavior was investigated, and the phase region was presented. With the help of cryogenic transmission electron microscopy (cryo-TEM) observations, deuterium nuclear magnetic resonance ((2)H NMR), and X-ray diffraction (XRD) measurements, the vesicles and planar sheets were determined. The chain length of C(n)H(2n+1)COOH has an important effect on the physical state of the hydrophobic chain, resulting in an obvious difference in the viscoelasticity of the solution samples. (ii) The existence of hydrogen bonds between fatty acids and their soaps in aqueous solutions was demonstrated by Fourier transform infrared (FT-IR) spectroscopy and molecule dynamical simulation. From the pH measurements, the pH ranges of the bilayer formation were at the pKa values of fatty acids, respectively. (iii) Counterions can be embedded in the stern layer of the bilayers and screen the electrostatic repulsion between the COO(-) anionic headgroups. FT-IR characterization demonstrated a bidentate bridging coordination mode between counterions and carboxylates. The conductivity measurements provided the degree

  13. A Burkholderia sacchari cell factory: production of poly-3-hydroxybutyrate, xylitol and xylonic acid from xylose-rich sugar mixtures.

    PubMed

    Raposo, Rodrigo S; de Almeida, M Catarina M D; de Oliveira, M da Conceição M A; da Fonseca, M Manuela; Cesário, M Teresa

    2017-01-25

    Efficient production of poly-3-hydroxybutyrate (P(3HB)) based on glucose-xylose mixtures simulating different types of lignocellulosic hydrolysate (LCH) was addressed using Burkholderia sacchari, a wild strain capable of metabolizing both sugars and producing P(3HB). Carbon catabolite repression was avoided by maintaining glucose concentration below 10g/L. Xylose concentrations above 30g/L were inhibitory for growth and production. In fed-batch cultivations, pulse size and feed addition rate were controlled in order to reach high productivities and efficient sugar consumptions. High xylose uptake and P(3HB) productivity were attained with glucose-rich mixtures (glucose/xylose ratio in the feed=1.5w/w) using high feeding rates, while with xylose-richer feeds (glucose/xylose=0.8w/w), a lower feeding rate is a robust strategy to avoid xylose build-up in the medium. Xylitol production was observed with xylose concentrations in the medium above 30-40g/L. With sugar mixtures featuring even lower glucose/xylose ratios, i.e. xylose-richer feeds (glucose/xylose=0.5), xylonic acid (a second byproduct) was produced. This is the first report of the ability of Burkholderia sacchari to produce both xylitol and xylonic acid.

  14. Biogenic and synthetic polyamines bind bovine serum albumin.

    PubMed

    Dubeau, S; Bourassa, P; Thomas, T J; Tajmir-Riahi, H A

    2010-06-14

    Biogenic polyamines are found to modulate protein synthesis at different levels, while polyamine analogues have shown major antitumor activity in multiple experimental models, including breast cancer. The aim of this study was to examine the interaction of bovine serum albumin (BSA) with biogenic polyamines, spermine and spermidine, and polyamine analogues 3,7,11,15-tetrazaheptadecane x 4 HCl (BE-333) and 3,7,11,15,19-pentazahenicosane x 5 HCl (BE-3333) in aqueous solution at physiological conditions. FTIR, UV-visible, CD, and fluorescence spectroscopic methods were used to determine the polyamine binding mode and the effects of polyamine complexation on protein stability and secondary structure. Structural analysis showed that polyamines bind BSA via both hydrophilic and hydrophobic interactions. Stronger polyamine-protein complexes formed with biogenic than synthetic polyamines with overall binding constants of K(spm) = 3.56 (+/-0.5) x 10(5) M(-1), K(spmd) = 1.77 (+/-0.4) x 10(5) M(-1), K(BE-333) = 1.11 (+/-0.3) x 10(4) M(-1) and K(BE-3333) = 3.90 (+/-0.7) x 10(4) M(-1) that correlate with their positively charged amino group contents. Major alterations of protein conformation were observed with reduction of alpha-helix from 63% (free protein) to 55-33% and increase of turn 12% (free protein) to 28-16% and random coil from 6% (free protein) to 24-17% in the polyamine-BSA complexes, indicating a partial protein unfolding. These data suggest that serum albumins might act as polyamine carrier proteins in delivering polyamine analogues to target tissues.

  15. Is biodegradation of bitumen a source of recalcitrant naphthenic acid mixtures in oil sands tailing pond waters?

    PubMed

    Quagraine, E K; Headley, J V; Peterson, H G

    2005-01-01

    Carboxylic acids are transient metabolites during the mineralization of petroleum hydrocarbons. Crude oils, however, vary in their proportion of the hydrocarbon components. Depending on structure, some carboxylic acid metabolites resist further biodegradation and persist in aquatic systems. During the extraction of oil sands bitumen, recalcitrant carboxylic acid mixtures, collectively referred to as naphthenic acids (NAs), are released into the wastewaters. These waters also contain unrecovered bitumen from the oil sands. The unextracted bitumen is often overlooked as a possible source of the petroleum acids. The present article discusses the literature data on the biotransformation of hydrocarbons in bitumen from oil sands to the corresponding petroleum carboxylic acids. Some insight is given on the mechanism of the biodegradation process. The susceptibility to biodegradation is affected by differences in alicyclic carboxylic acids such as carbon chain length, chain branching, and the oddness or evenness of carbon chain containing the carboxylic group, positions where alkyl groups are substituted on the cyclic ring, geometrical isomerism, and number of cyclic rings.

  16. Mixture-amount design and response surface modeling to assess the effects of flavonoids and phenolic acids on developmental performance of Anastrepha ludens

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A mixture-amount experimental design and response surface modeling were used to study the effects of three flavonoids and two phenolic acids, alone or in mixtures, in an artificial larval diet on the development and survival of Mexican fruit fly (Anastrepha ludens [Loew]). Pupal weight, percentage o...

  17. Molecular dynamics investigation of separation of hydrogen sulfide from acidic gas mixtures inside metal-doped graphite micropores.

    PubMed

    Huang, Pei-Hsing

    2015-09-21

    The separation of poisonous compounds from various process fluids has long been highly intractable, motivating the present study on the dynamic separation of H2S in acidic-gas-mixture-filled micropores. The molecular dynamics approach, coupled with the isothermal-isochoric ensemble, was used to model the molecular interactions and adsorption of H2S/CO2/CO/H2O mixtures inside metal-doped graphite slits. Due to the difference in the adsorption characteristics between the two distinct adsorbent materials, the metal dopant in the graphitic micropores leads to competitive adsorption, i.e. the Au and graphite walls compete to capture free adsorbates. The effects of competitive adsorption, coupled with changes in the gas temperature, concentration, constituent ratio and slit width on the constituent separation of mixtures were systematically studied. The molecule-wall binding energies calculated in this work (those of H2S, H2O and CO on Au walls and those of H2O, CO and CO2 on graphite walls) show good agreement with those obtained using density functional theory (DFT) and experimental results. The z-directional self-diffusivities (Dz) for adsorbates inside the slit ranged from 10(-9) to 10(-7) m(2) s(-1) as the temperature was increased from 10 to 500 K. The values are comparable with those for a typical microporous fluid (10(-8)-10(-9) m(2) s(-1) in a condensed phase and 10(-6)-10(-7) m(2) s(-1) in the gaseous state). The formation of H-bonding networks and hydrates of H2S is disadvantageous for the separation of mixtures. The results indicate that H2S can be efficiently separated from acidic gas mixtures onto the Au(111) surface by (i) reducing the mole fraction of H2S and H2O in the mixtures, (ii) raising the gas temperature to the high temperature limit (≥400 K), and (iii) lowering the slit width to below the threshold dimension (≤23.26 Å).

  18. Polyamines and α-Carbonic Anhydrases.

    PubMed

    Scozzafava, Andrea; Supuran, Claudiu T; Carta, Fabrizio

    2016-12-15

    Natural products represent a straightforward source for molecular structures bearing a vast array of chemical features and potentially useful for biomedical purposes. Recent examples of this type include the discovery of the coumarins and the polyamine natural products as atypical chemotypes for the inhibition of the metalloenzymes carbonic anhydrases (CAs; EC 4.2.2.1). CA enzymes are established pharmacological targets for important pathologies, which, among others, include glaucoma, hypoxic tumors, and central nervous system (CNS)-affecting diseases. Moreover, they are expressed in many bacteria, fungi and helminths which are the etiological agents of the majority of infectious diseases. In this context, natural products represent the ideal source of new and selective druggable CA modulators for biomedical purposes. Herein we report the state of the art on polyamines of natural origin as well as of synthetic derivatives as inhibitors of human CAs.

  19. Genomic identification and biochemical characterization of the mammalian polyamine oxidase involved in polyamine back-conversion.

    PubMed Central

    Vujcic, Slavoljub; Liang, Ping; Diegelman, Paula; Kramer, Debora L; Porter, Carl W

    2003-01-01

    In the polyamine back-conversion pathway, spermine and spermidine are first acetylated by spermidine/spermine N1 -acetyltransferase (SSAT) and then oxidized by polyamine oxidase (PAO) to produce spermidine and putrescine respectively. Although PAO was first purified more than two decades ago, the protein has not yet been linked to genomic sequences. In the present study, we apply a BLAST search strategy to identify novel oxidase sequences located on human chromosome 10 and mouse chromosome 7. Homologous mammalian cDNAs derived from human brain and mouse mammary tumour were deduced to encode proteins of approx. 55 kDa having 82% sequence identity. When either cDNA was transiently transfected into HEK-293 cells, intracellular spermine pools decreased by approx. 30%, whereas spermidine increased 2-4-fold. Lysates of human PAO cDNA-transfected HEK-293 cells, but not vector-transfected cells, rapidly oxidized N1-acetylspermine to spermidine. Substrate specificity determinations with the lysate assay revealed a preference ranking of N1-acetylspermine= N1-acetylspermidine> N1,N12-diacetylspermine>>spermine; spermidine was not acted upon. This ranking is identical to that reported for purified PAO and distinctly different from the recently identified spermine oxidase (SMO), which prefers spermine over N1-acetylspermine. Monoethyl- and diethylspermine analogues also served as substrates for PAO, and were internally cleaved adjacent to a secondary amine. We deduce that the present oxidase sequences are those of the FAD-dependent PAO involved in the polyamine back-conversion pathway. In Northern blot analysis, PAO mRNA was much less abundant in HEK-293 cells than SMO or SSAT mRNA, and all three were differentially induced in a similar manner by selected polyamine analogues. The identification of PAO sequences, together with the recently identified SMO sequences, provides new opportunities for understanding the dynamics of polyamine homoeostasis and for interpreting metabolic

  20. A Functional Tricarboxylic Acid Cycle Operates during Growth of Bordetella pertussis on Amino Acid Mixtures as Sole Carbon Substrates

    PubMed Central

    Garnier, Dominique; Speck, Denis

    2015-01-01

    It has been claimed that citrate synthase, aconitase and isocitrate dehydrogenase activities are non-functional in Bordetella pertussis and that this might explain why this bacterium’s growth is sometimes associated with accumulation of polyhydroxybutyrate (PHB) and/or free fatty acids. However, the sequenced genome includes the entire citric acid pathway genes. Furthermore, these genes were expressed and the corresponding enzyme activities detected at high levels for the pathway when grown on a defined medium imitating the amino acid content of complex media often used for growth of this pathogenic microorganism. In addition, no significant PHB or fatty acids could be detected. Analysis of the carbon balance and stoichiometric flux analysis based on specific rates of amino acid consumption, and estimated biomass requirements coherent with the observed growth rate, clearly indicate that a fully functional tricarboxylic acid cycle operates in contrast to previous reports. PMID:26684737

  1. A Functional Tricarboxylic Acid Cycle Operates during Growth of Bordetella pertussis on Amino Acid Mixtures as Sole Carbon Substrates.

    PubMed

    Izac, Marie; Garnier, Dominique; Speck, Denis; Lindley, Nic D

    2015-01-01

    It has been claimed that citrate synthase, aconitase and isocitrate dehydrogenase activities are non-functional in Bordetella pertussis and that this might explain why this bacterium's growth is sometimes associated with accumulation of polyhydroxybutyrate (PHB) and/or free fatty acids. However, the sequenced genome includes the entire citric acid pathway genes. Furthermore, these genes were expressed and the corresponding enzyme activities detected at high levels for the pathway when grown on a defined medium imitating the amino acid content of complex media often used for growth of this pathogenic microorganism. In addition, no significant PHB or fatty acids could be detected. Analysis of the carbon balance and stoichiometric flux analysis based on specific rates of amino acid consumption, and estimated biomass requirements coherent with the observed growth rate, clearly indicate that a fully functional tricarboxylic acid cycle operates in contrast to previous reports.

  2. Synergistic effects of perfluoroalkyl acids mixtures with J-shaped concentration-responses on viability of a human liver cell line.

    PubMed

    Hu, Jiayue; Li, Juan; Wang, Jianshe; Zhang, Aiqian; Dai, Jiayin

    2014-02-01

    Some perfluoroalkyl acids (PFAAs) are highly persistent and bioaccumulative, resulting in their broad coexisting distribution in humans and the environment. Our aim was to investigate the individual and joint effects of PFAAs on cellular viability of a human liver cell line (HL-7702) using the MTT assay. Equipartition ray design and equivalent-effect concentration ratio (EECR) mixtures were used to investigate the binary and multiple effects of PFAAs, respectively. All tested PFAAs mixtures and the individuals (except perfluorododecanoic acid (PFDoDA) and perfluorotetradecanoic acid (PFTeDA)) showed obvious non-monotonic J-shaped concentration-response curves (CRC) on HL-7702. The inhibitory effect of individual PFAAs increased with the elongation of the carbon chain and was dominated by their molecular volume. The three binary mixtures (PFOA/S, PFHxA/S and PFBA/S) showed that synergistic effects occurred under effective inhibitory concentrations (IC) of IC0, IC10, and IC50 in mixtures, while for IC-20 the synergistic effect only occurred under higher PFSA proportion in mixtures. Furthermore, EECR mixtures of the nine individual PFAAs with J-shaped CRC also showed synergistic effects. However, mixtures of the eleven individual PFAAs including those with S-shaped CRC resulted in partial addition effects on HL-7702. Our results indicated that the individual stimulatory responses of HL-7702 to PFAA may produce adverse effects in mixtures at relevant dose levels.

  3. Polyamines as Snake Toxins and Their Probable Pharmacological Functions in Envenomation

    PubMed Central

    Aird, Steven D.; Villar Briones, Alejandro; Roy, Michael C.; Mikheyev, Alexander S.

    2016-01-01

    While decades of research have focused on snake venom proteins, far less attention has been paid to small organic venom constituents. Using mostly pooled samples, we surveyed 31 venoms (six elapid, six viperid, and 19 crotalid) for spermine, spermidine, putrescine, and cadaverine. Most venoms contained all four polyamines, although some in essentially trace quantities. Spermine is a potentially significant component of many viperid and crotalid venoms (≤0.16% by mass, or 7.9 µmol/g); however, it is almost completely absent from elapid venoms assayed. All elapid venoms contained larger molar quantities of putrescine and cadaverine than spermine, but still at levels that are likely to be biologically insignificant. As with venom purines, polyamines impact numerous physiological targets in ways that are consistent with the objectives of prey envenomation, prey immobilization via hypotension and paralysis. Most venoms probably do not contain sufficient quantities of polyamines to induce systemic effects in prey; however, local effects seem probable. A review of the pharmacological literature suggests that spermine could contribute to prey hypotension and paralysis by interacting with N-methyl-d-aspartate (NMDA) and α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptors, nicotinic and muscarinic acetylcholine receptors, γ-Aminobutyric acid (GABA) receptors, blood platelets, ryanodine receptors, and Ca2+-ATPase. It also blocks many types of cation-permeable channels by interacting with negatively charged amino acid residues in the channel mouths. The site of envenomation probably determines which physiological targets assume the greatest importance; however, venom-induced liberation of endogenous, intracellular stores of polyamines could potentially have systemic implications and may contribute significantly to envenomation sequelae. PMID:27681740

  4. A probe on the intermolecular forces in diisopropyl ether-n-butyric acid mixture by dielectric, FTIR studies and quantum chemical calculations.

    PubMed

    Arivazhagan, G; Shanmugam, R; Elangovan, A

    2013-03-15

    The results of FTIR spectral measurement on equimolar diisopropyl ether-butyric acid binary mixture and quantum chemical calculations on the complex molecule have been presented. Dielectric studies have been carried out on the binary mixture over the entire composition range and at four different temperatures 303 K, 308 K, 313 K and 318 K. n-Butyric acid seems to prefer less polar ether to interact with it. It appears that the usual interpretation of variation of static dielectric constant and positive deviation of excess permittivity from ideal mixture behavior needs to be relooked.

  5. A class frequency mixture model that adjusts for site-specific amino acid frequencies and improves inference of protein phylogeny

    PubMed Central

    2008-01-01

    Background Widely used substitution models for proteins, such as the Jones-Taylor-Thornton (JTT) or Whelan and Goldman (WAG) models, are based on empirical amino acid interchange matrices estimated from databases of protein alignments that incorporate the average amino acid frequencies of the data set under examination (e.g JTT + F). Variation in the evolutionary process between sites is typically modelled by a rates-across-sites distribution such as the gamma (Γ) distribution. However, sites in proteins also vary in the kinds of amino acid interchanges that are favoured, a feature that is ignored by standard empirical substitution matrices. Here we examine the degree to which the pattern of evolution at sites differs from that expected based on empirical amino acid substitution models and evaluate the impact of these deviations on phylogenetic estimation. Results We analyzed 21 large protein alignments with two statistical tests designed to detect deviation of site-specific amino acid distributions from data simulated under the standard empirical substitution model: JTT+ F + Γ. We found that the number of states at a given site is, on average, smaller and the frequencies of these states are less uniform than expected based on a JTT + F + Γ substitution model. With a four-taxon example, we show that phylogenetic estimation under the JTT + F + Γ model is seriously biased by a long-branch attraction artefact if the data are simulated under a model utilizing the observed site-specific amino acid frequencies from an alignment. Principal components analyses indicate the existence of at least four major site-specific frequency classes in these 21 protein alignments. Using a mixture model with these four separate classes of site-specific state frequencies plus a fifth class of global frequencies (the JTT + cF + Γ model), significant improvements in model fit for real data sets can be achieved. This simple mixture model also reduces the long-branch attraction problem

  6. Fast Fourier Transform IR Characterization of Epoxy GY Systems Crosslinked with Aliphatic and Cycloaliphatic EH Polyamine Adducts

    PubMed Central

    Nikolic, Goran; Zlatkovic, Sasa; Cakic, Milorad; Cakic, Suzana; Lacnjevac, Caslav; Rajic, Zoran

    2010-01-01

    The use of fast FT-IR spectroscopy as a sensitive method to estimate a change of the crosslinking kinetics of epoxy resin with polyamine adducts is described in this study. A new epoxy formulation based on the use of polyamine adducts as the hardeners was analyzed. Crosslinking reactions of the different stoichiometric mixtures of the unmodified GY250 epoxy resin with the aliphatic EH606 and the cycloaliphatic EH637 polyamine adducts were studied using mid FT-IR spectroscopic techniques. As the crosslinking proceeded, the primary amine groups in polyamine adduct are converted to secondary and the tertiary amines. The decrease in the IR band intensity of epoxy groups at about 915 cm−1, as well as at about 3,056 cm−1, was observed due to process. Mid IR spectral analysis was used to calculate the content of the epoxy groups as a function of crosslinking time and the crosslinking degree of resin. The amount of all the epoxy species was estimated from IR spectra to changes during the crosslinking kinetics of epichlorhydrin. PMID:22315562

  7. Polyamines in foods: development of a food database

    PubMed Central

    Ali, Mohamed Atiya; Poortvliet, Eric; Strömberg, Roger; Yngve, Agneta

    2011-01-01

    Background Knowing the levels of polyamines (putrescine, spermidine, and spermine) in different foods is of interest due to the association of these bioactive nutrients to health and diseases. There is a lack of relevant information on their contents in foods. Objective To develop a food polyamine database from published data by which polyamine intake and food contribution to this intake can be estimated, and to determine the levels of polyamines in Swedish dairy products. Design Extensive literature search and laboratory analysis of selected Swedish dairy products. Polyamine contents in foods were collected using an extensive literature search of databases. Polyamines in different types of Swedish dairy products (milk with different fat percentages, yogurt, cheeses, and sour milk) were determined using high performance liquid chromatography (HPLC) equipped with a UV detector. Results Fruits and cheese were the highest sources of putrescine, while vegetables and meat products were found to be rich in spermidine and spermine, respectively. The content of polyamines in cheese varied considerably between studies. In analyzed Swedish dairy products, matured cheese had the highest total polyamine contents with values of 52.3, 1.2, and 2.6 mg/kg for putrescine, spermidine, and spermine, respectively. Low fat milk had higher putrescine and spermidine, 1.2 and 1.0 mg/kg, respectively, than the other types of milk. Conclusions The database aids other researchers in their quest for information regarding polyamine intake from foods. Connecting the polyamine contents in food with the Swedish Food Database allows for estimation of polyamine contents per portion. PMID:21249159

  8. Stability of binary SAMs formed by omega-acid and alcohol functionalized thiol mixtures.

    PubMed

    Tielens, Frederik; Humblot, Vincent; Pradier, Claire-Marie; Calatayud, Monica; Illas, Francesc

    2009-09-01

    A simple model is presented to describe the mixing process of acid- and alcohol-terminated thiol self-assembled monolayers (SAMs) on Au(111). It was found that the low-concentration acid-terminated SAMs are enriched in acid thiol compared with the original solution from which the SAM is made. Due to the relatively strong interaction between acid and alcohol head groups, homogeneously mixed SAMs showing alcohol/acid pairs are preferred when the acid-terminated thiol fraction in solution is below or equal to 50%. This particular behavior affecting the mixing process is explained using atomistic first-principle thermodynamics. The calculated phase diagram has been discussed and interpreted with the help of XPS.

  9. Effects of acidic mixtures on pulmonary macrophage functions: A pilot study. Final report

    SciTech Connect

    Phalen, R.F.; Kikkawa, Y.; Nadziejko, C.; Kleinman, M.T.

    1992-02-01

    Fischer 344 rats were examined for effects of inhaled nitric acid and ozone on macrophage cell function, to evaluate new endpoints for future acid inhalation studies. Pulmonary macrophage respiratory burst activity, production of arachidonic acid metabolites (leukotriene B4 and leukotriene C4) by macrophages, and lavage fluid elastase inhibitory capacity were found to be affected by in vivo exposure to nitric acid vapor, alone or in combination with ozone. These results have implications with respect to the development of lung infections, asthma, and emphysema.

  10. Effect of hardness on acute toxicity of metal mixtures using Daphnia magna: prediction of acid mine drainage toxicity.

    PubMed

    Yim, Jin Hee; Kim, Kyoung W; Kim, Sang D

    2006-11-02

    In this study, the effect of hardness on the combined outcome of metal mixtures was investigated using Daphnia magna. The toxic unit (TU) was calculated using modified LC(50) values based on the hardness (i.e., LC(50-soft) and LC(50-hard)). From a bioassay test, the degree of sensitivity to hardness on the toxicity changes was in the order: Cdmixture toxicity tests, the difference in the test solution hardness was found to clearly cause different toxicities, as determined by the TU calculated by the LC(50-hard), using the toxicity of a standard culture medium as the reference. That is, approximately four to five times higher toxicity was observed in soft (i.e., 44+/-4 mg/L as CaCO(3)) rather than hard water (i.e., 150+/-10mg/L as CaCO(3)) test solutions. In the tests where the modified reference toxicity values (i.e., LC(50-soft) and LC(50-hard) for soft and hard test solution, respectively) obtained from the individual metal toxicity tests with different hardness were used to calculate the TU, the results showed very similar D. magna toxicities to those of the TU from the mixture of soft and hard test solutions, regardless of the hardness. According to the toxicity results of the mixture, the aquatic toxic effects of the acid mine drainage (AMD) collected from mine areas that contained metal mixtures were investigated using Daphnia magna and the modified LC(50) value of the TU hardness function calculated for varying solution hardness. The results of the biological WET test closely matched our overall prediction, with significant correlation, having a p-value of 0.513 in one way ANOVA test (n=19). Therefore, this study revealed that the predicted toxicity of the metal mixture agreed well with the biological toxicity test when the modified LC(50) value was employed as the basis of hardness in the TU calculation.

  11. Electrochemistry for biofuel generation: transformation of fatty acids and triglycerides to diesel-like olefin/ether mixtures and olefins.

    PubMed

    dos Santos, Tatiane R; Harnisch, Falk; Nilges, Peter; Schröder, Uwe

    2015-03-01

    Electroorganic synthesis can be exploited for the production of biofuels from fatty acids and triglycerides. With Coulomb efficiencies (CE) of up to 50 %, the electrochemical decarboxylation of fatty acids in methanolic and ethanolic solutions leads to the formation of diesel-like olefin/ether mixtures. Triglycerides can be directly converted in aqueous solutions by using sonoelectrochemistry, with olefins as the main products (with a CE of more than 20 %). The latter reaction, however, is terminated at around 50 % substrate conversion by the produced side-product glycerol. An energy analysis shows that the electrochemical olefin synthesis can be an energetically competitive, sustainable, and--in comparison with established processes--economically feasible alternative for the exploitation of fats and oils for biofuel production.

  12. Ionotropic Chemosensory Receptors Mediate the Taste and Smell of Polyamines.

    PubMed

    Hussain, Ashiq; Zhang, Mo; Üçpunar, Habibe K; Svensson, Thomas; Quillery, Elsa; Gompel, Nicolas; Ignell, Rickard; Grunwald Kadow, Ilona C

    2016-05-01

    The ability to find and consume nutrient-rich diets for successful reproduction and survival is fundamental to animal life. Among the nutrients important for all animals are polyamines, a class of pungent smelling compounds required in numerous cellular and organismic processes. Polyamine deficiency or excess has detrimental effects on health, cognitive function, reproduction, and lifespan. Here, we show that a diet high in polyamine is beneficial and increases reproductive success of flies, and we unravel the sensory mechanisms that attract Drosophila to polyamine-rich food and egg-laying substrates. Using a combination of behavioral genetics and in vivo calcium imaging, we demonstrate that Drosophila uses multisensory detection to find and evaluate polyamines present in overripe and fermenting fruit, their favored feeding and egg-laying substrate. In the olfactory system, two coexpressed ionotropic receptors (IRs), IR76b and IR41a, mediate the long-range attraction to the odor. In the gustatory system, multimodal taste sensation by IR76b receptor and GR66a bitter receptor neurons is used to evaluate quality and valence of the polyamine providing a mechanism for the fly's high attraction to polyamine-rich and sweet decaying fruit. Given their universal and highly conserved biological roles, we propose that the ability to evaluate food for polyamine content may impact health and reproductive success also of other animals including humans.

  13. Polyamine Metabolism in Fungi with Emphasis on Phytopathogenic Species

    PubMed Central

    Valdés-Santiago, Laura; Cervantes-Chávez, José Antonio; León-Ramírez, Claudia Geraldine; Ruiz-Herrera, José

    2012-01-01

    Polyamines are essential metabolites present in all living organisms, and this subject has attracted the attention of researchers worldwide interested in defining their mode of action in the variable cell functions in which they are involved, from growth to development and differentiation. Although the mechanism of polyamine synthesis is almost universal, different biological groups show interesting differences in this aspect that require to be further analyzed. For these studies, fungi represent interesting models because of their characteristics and facility of analysis. During the last decades fungi have contributed to the understanding of polyamine metabolism. The use of specific inhibitors and the isolation of mutants have allowed the manipulation of the pathway providing information on its regulation. During host-fungus interaction polyamine metabolism suffers striking changes in response to infection, which requires examination. Additionally the role of polyamine transporter is getting importance because of its role in polyamine regulation. In this paper we analyze the metabolism of polyamines in fungi, and the difference of this process with other biological groups. Of particular importance is the difference of polyamine biosynthesis between fungi and plants, which makes this process an attractive target for the control of phytopathogenic fungi. PMID:22957208

  14. Ionotropic Chemosensory Receptors Mediate the Taste and Smell of Polyamines

    PubMed Central

    Üçpunar, Habibe K.; Svensson, Thomas; Quillery, Elsa; Gompel, Nicolas; Ignell, Rickard; Grunwald Kadow, Ilona C.

    2016-01-01

    The ability to find and consume nutrient-rich diets for successful reproduction and survival is fundamental to animal life. Among the nutrients important for all animals are polyamines, a class of pungent smelling compounds required in numerous cellular and organismic processes. Polyamine deficiency or excess has detrimental effects on health, cognitive function, reproduction, and lifespan. Here, we show that a diet high in polyamine is beneficial and increases reproductive success of flies, and we unravel the sensory mechanisms that attract Drosophila to polyamine-rich food and egg-laying substrates. Using a combination of behavioral genetics and in vivo calcium imaging, we demonstrate that Drosophila uses multisensory detection to find and evaluate polyamines present in overripe and fermenting fruit, their favored feeding and egg-laying substrate. In the olfactory system, two coexpressed ionotropic receptors (IRs), IR76b and IR41a, mediate the long-range attraction to the odor. In the gustatory system, multimodal taste sensation by IR76b receptor and GR66a bitter receptor neurons is used to evaluate quality and valence of the polyamine providing a mechanism for the fly’s high attraction to polyamine-rich and sweet decaying fruit. Given their universal and highly conserved biological roles, we propose that the ability to evaluate food for polyamine content may impact health and reproductive success also of other animals including humans. PMID:27145030

  15. Factors influencing inapplicability of cosolvency-induced model on organic acid sorption onto humic substance from methanol mixture.

    PubMed

    Kim, Minhee; Kim, Juhee; Kim, Jeong-Gyu; Hyun, Seunghun

    2015-10-01

    Applicability of cosolvency model for describing the sorption of organic acids to humic substance was investigated by analyzing dataset of sorption (K m) and solubility (S m) of selected solutes (benzoic acid, 1-naphthoic acid, 2,4-dichlorophenoxyacetic acid, and 2,4,6-trichlorophenol (2,4,6-TCP)) as a function of pH(appCME) (apparent pH of liquid phase) and f c (methanol volume fractions). For all solutes, the K m decreased with f c with the K m reduction being less than the S m-based prediction. The slope of log K m-f c plot in the three organic carboxylic acids was well correlated with their cosolvency power, whereas the data of organic phenolic acid (2,4,6-TCP) was placed above the trend, indicating the different actions of functional groups. The occurrence of Ca(2+) bridge between carboxylate and negatively charged humic surface may explain this phenomenon. Normalizing the K m to the corresponding S m (α' = K m/S m) was not in unity over the pH(app)-f c range but decreased with f c, indicating a possible structural modification of sorption domain favoring extra sorption. For a given solute, the α' of neutral species was always greater than that of anionic species, showing that extra interaction will be likely at pH(app) acids by humic substance in methanol/water mixtures. Modification of humic structure and hydrophilic interaction (such as Ca(2+) bridge and same-charge repulsion) is considered a relevant process that possibly restricts the applicability of the cosolvency model.

  16. SA improvement of hyperhydricity reversion in Thymus daenensis shoots culture may be associated with polyamines changes.

    PubMed

    Hassannejad, Sahar; Bernard, Françoise; Mirzajani, Fateme; Gholami, Morteza

    2012-02-01

    In shoot cultures of Thymus daenensis, hyperhydricity syndrome promoted by benzyladenine (BA) is characterised by the development of chlorophyll-deficient shoots with a high water content and reduced growth that is less differentiated. By removing the BA from the culture medium, the hyperhydricity was reversed, and the reversion toward a normal growth in vitro was more efficient in shoots treated with 5 μM of salicylic acid (SA), showing a significant increase in chlorophyll b after 4 weeks of culture. In the present study, the effect of salicylic acid on the reversion of shoot hyperhydricity was investigated at the level of the free, soluble and insoluble conjugated polyamine content. In T. daenensis micropropagated shoots, the level of polyamines was high, with a predominance of putrescine. BA, which triggered hyperhydricity, caused a reduction of the polyamine (PA) content by one-half due to a decrease in the putrescine content and insoluble conjugated PAs that were not detected in the hyperhydric shoots. In the reverted shoots, changes of the free polyamines, spermidine and, more notably, spermine, were shown. The spermine content doubled after 4 weeks of culture, and its amount was the same as that found in normal shoots, suggesting that free spermine could be particularly involved in the reversion of hyperhydricity. In the SA-reverted tissues, the PA pattern was marked with a transient increase of free putrescine, spermidine and spermine and an enhancement of soluble conjugated spermine. This transitory SA-dependent amplification of PAs was concomitant with a remarkable transient increase of H(2)O(2), suggesting that SA may be implicated in PA signalling pathways for tissue differentiation during the reversion of hyperhydricity in T. daenensis.

  17. Interaction of linear polyamines with negatively charged phospholipids: the effect of polyamine charge distance.

    PubMed

    Finger, Sebastian; Schwieger, Christian; Arouri, Ahmad; Kerth, Andreas; Blume, Alfred

    2014-07-01

    The binding of cationic polyamines to negatively charged lipid membranes is driven by electrostatic interactions and additional hydrophobic contributions. We investigated the effect of polyamines with different number of charges and charge separation on the phase transition behavior of vesicles of phosphatidylglycerols (dipalmitoylphosphatidylglycerol and dimyristoylphosphatidylglycerol) to differentiate between effects caused by the number of charges, the charge distance, and the hydrophobicity of the methylene spacer. Using differential scanning calorimetry and Fourier transform infrared spectroscopy complemented with monolayer experiments, we found that the binding constant of polyamines to negatively charged lipid vesicles depends as expected on the number of charges. However, for diamines, the effect of binding on the main phase transition of phosphatidylglycerols (PGs) is also strongly influenced by the charge distance between the ammonium groups in the backbone. Oligoamines with charges separated by two or three methylene groups bind more strongly and have larger stabilizing effects on the lipid gel phase of PGs. With multivalent polyamines, the appearance of several transition peaks points to effects of molecular crowding on the surface, i.e., binding of only two or three charges to the surface in the case of spermine, and possible concomitant domain formation.

  18. Environmentally Realistic Mixtures of Haloacetic Acids Exhibit Concentration-Dependent Departures from Dose Additivity

    EPA Science Inventory

    Disinfection byproducts (DBPs), including haloacetic acids (HAAs), are formed when oxidizing disinfectants react with inorganic and organic matter in water. Drinking water is assayed routinely for 9 HAAs (HAA9): chloro-, dichloro-, trichloro-, bromo-, dibromo-, tribrorno-, bromoc...

  19. Nine and Ten chemical haloacetic acid mixtures exhibit concentration-dependent departure from dose additivity

    EPA Science Inventory

    Disinfection of water greatly decreases waterborne disease. Disinfection byproducts (DBPs), including haloacetic acids (HAAs), are formed when oxidizing disinfectants react with inorganic and organic matter in water. Water providers routinely assay for 9 HAAs in finished drinking...

  20. Total parenteral nutrition-associated cholestasis in rats: comparison of different amino acid mixtures.

    PubMed

    Belli, D C; Fournier, L A; Lepage, G; Yousef, I; Weber, A M; Tuchweber, B; Roy, C C

    1987-01-01

    It has been suggested that the quantity of amino acids perfused is a pathogenetic factor in total parenteral nutrition (TPN)-associated hepatotoxicity. However, the effect of the qualitative pattern of amino acid solutions has not been studied. Rats on parenteral nutrition for 5 days received 10.2 g of dextrose and 3.4 g of amino acids daily. Bile flow (microliter/min/g liver protein) after administration of Vamin was 16.2 +/- 0.8, which was similar to that in controls given chow and dextrose iv, but it was significantly higher (p less than 0.001) than those on Travasol (12.3 +/- 0.8). The decrease in bile flow was not related to the large concentrations of alanine and glycine present in Travasol. However, the addition to Travasol of serine present only in Vamin increased bile flow significantly. Bile acid secretion rate, biliary lipid constituents, calcium, sodium, and glucose showed little change. In contrast, alpha-amino nitrogen was increased (p less than 0.05) in Vamin-perfused animals. Steatosis was noted in only a few animals in the Travasol group, and was not associated with an increase in the triglycerides content of the liver. Glycogen and protein content of the livers did not differ. The data show that the composition of amino acid solutions may be a determinant of TPN-induced cholestasis and suggest that the presence of methyl donor amino acids may have a protective effect.

  1. Analysis of mixtures of fatty acids and fatty alcohols in fermentation broth.

    PubMed

    Liu, Yilan; Chen, Ting; Yang, Maohua; Wang, Caixia; Huo, Weiyan; Yan, Daojiang; Chen, Jinjin; Zhou, Jiemin; Xing, Jianmin

    2014-01-03

    Microbial production of fatty acids and fatty alcohols has attracted increasing concerns because of energy crisis and environmental impact of fossil fuels. Therefore, simple and efficient methods for the extraction and quantification of these compounds become necessary. In this study, a high-performance liquid chromatography-refractive index detection (HPLC-RID) method was developed for the simultaneous quantification of fatty acids and fatty alcohols in these samples. The optimum chromatographic conditions are C18 column eluted with methanol:water:acetic acid (90:9.9:0.1, v/v/v); column temperature, 26°C; flow rate, 1.0mL/min. Calibration curves of all selected analytes showed good linearity (r(2)≥0.9989). The intra-day and inter-day relative standard deviations (RSDs) of the 10 compounds were less than 4.46% and 5.38%, respectively, which indicated that the method had good repeatability and precision. Besides, a method for simultaneous extraction of fatty acids and fatty alcohols from fermentation broth was optimized by orthogonal design. The optimal extraction conditions were as follows: solvent, ethyl acetate; solvent to sample ratio, 0.5:1; rotation speed, 2min at 260rpm; extraction temperature, 10°C. This study provides simple and fast methods to simultaneously extract and quantify fatty acids and fatty alcohols for the first time. It will be useful for the study of microbial production of these products.

  2. Sorption of acidic organic solute onto kaolinitic soils from methanol-water mixtures.

    PubMed

    Kim, Juhee; Kim, Minhee; Hyun, Seunghun; Kim, Jeong-Gyu; Ok, Yong Sik

    2012-01-01

    The fate of the acidic organic solute from the soil-water-solvent system is not well-understood. In this study, the effect of the acidic functional group of organic solute in the sorption from cosolvent system was evaluated. The sorption of naphthalene (NAP) and 1-naphthoic acid (1-NAPA) by three kaolinitic soils and two model sorbents (kaolinite and humic acid) were measured as functions of the methanol volume fractions (f (c) ≤ 0.4) and ionic compositions (CaCl(2) and KCl). The solubility of 1-NAPA was also measured in various ionic compositions. The sorption data were interpreted using the cosolvency-induced sorption model. The K (m) values (= the linear sorption coefficient) of NAP with kaolinitic soil for both ionic compositions was log linearly decreased with f (c). However, the K (m) values of 1-NAPA with both ionic compositions remained relatively constant over the f (c) range. For the model sorbent, the K (m) values of 1-NAPA with kaolinite for the KCl system and with humic acid for both ionic compositions decreased with f (c), while the sorption of 1-NAPA with kaolinite for the CaCl(2) system was increased with f (c). From the solubility data of 1-NAPA with f (c), no significant difference was observed with the different ionic compositions, indicating an insignificant change in the aqueous activity of the liquid phase. In conclusion, the enhanced 1-NAPA sorption, greater than that predicted from the cosolvency-induced model, was due to an untraceable interaction between the carboxylate and hydrophilic soil domain in the methanol-water system. Therefore, in order to accurately predict the environmental fate of acidic pesticides and organic solutes, an effort to quantitatively incorporate the enhanced hydrophilic sorption into the current cosolvency-induced sorption model is required.

  3. Structure and Proton Conductivity in Mixtures of Poly(acrylic acid) and Imidazole

    NASA Astrophysics Data System (ADS)

    Yang, Han-Chang; Griffin, Philip J.; Winey, Karen I.; University of Pennsylvania Team

    2015-03-01

    Proton conductivity in polymer electrolyte membranes (PEMs) typically involves water, which requires that during operation the humidity of the PEM be carefully controlled. In contrast, anhydrous protic polymer membranes promote proton transport by incorporating heterocyclic molecules, such as imidazole and its derivatives, into acid-containing polymers. In this work, we explore the interplay between nanoscale-structure and proton conduction of poly(acrylic acid) (PAA) blended at varying compositions with 2-ethyl-4-methylimidazole (EMI). We present the glass transition temperature from differential scanning calorimetry, morphology characterization from X-ray scattering, and proton conductivity from electrical impedance spectroscopy.

  4. Interaction of polyamines and mTOR signaling in the synthesis of antizyme (AZ)

    PubMed Central

    Ray, Ramesh M.; Bavaria, Mitul; Johnson, Leonard R.

    2015-01-01

    Tissue polyamine levels are largely determined by the activity of ornithine decarboxylase (ODC, EC 4.1.17), which catalyzes the conversion of ornithine to the diamine putrescine. The activity of the enzyme is primarily regulated by a negative feedback mechanism involving ODC antizyme (AZ). Our previous studies demonstrated that AZ synthesis is stimulated by the absence of amino acids, the levels of which are sensed by the mTOR complex containing TORC1, which is stimulated by amino acids and inhibited by their absence, and TORC2 the function of which is not well defined. Polyamines, which cause a +1 ribosomal frameshift during the translation of AZ mRNA are required to increase AZ synthesis in both the presence and absence of amino acids. Amino acid starvation increases TORC2 activity. We have demonstrated that mTORC2 activity is necessary for AZ synthesis in the absence of amino acids. Tuberous sclerosis protein (TSC), a negative regulator of mTOR function regulates the activities of both the TORC1 and TORC2. TSC2 knockdown increased mTORC1 activity with concomitant inhibition of mTORC2 activity eliminating AZ induction in the absence of amino acids as well as that induced by spermidine. Thus, these results clearly demonstrate that in addition to polyamines, mTORC2 activity is necessary for AZ synthesis. Moreover, our results support a role for mTORC2 in the synthesis of a specific protein, AZ, which regulates growth of intestinal epithelial cells. PMID:26093026

  5. Mineralization of 2,4-Dichlorophenoxyacetic Acid (2,4-D) and Mixtures of 2,4-D and 2,4,5-Trichlorophenoxyacetic Acid by Phanerochaete chrysosporium

    PubMed Central

    Yadav, J. S.; Reddy, C. A.

    1993-01-01

    Evidence is presented for mineralization of 2,4-dichlorophenoxyacetic acid (2,4-D) in nutrient-rich media (high-nitrogen and malt extract media) by wild-type Phanerochaete chrysosporium and by a peroxidase-negative mutant of this organism. Mass balance analysis of [U-ring-14C]2,4-D mineralization in malt extract cultures showed 82.7% recovery of radioactivity. Of this, 38.6% was released as 14CO2 and 27.0, 11.2, and 5.9% were present in the aqueous, methylene chloride, and mycelial fractions, respectively. 2,4-D and 2,4,5-trichlorophenoxyacetic acid (2,4,5-T) were simultaneously mineralized when presented as a mixture, and mutual inhibition of degradation was not observed. In contrast, a relatively higher rate of mineralization of 2,4-D and 2,4,5-T was observed when these compounds were tested as mixtures than when they were tested alone. PMID:16349039

  6. Structural Investigations of Silica Polyamine Composites: Surface Coverage, Metal Ion Coordination, and Ligand Modification

    SciTech Connect

    Hughes, Mark; Nielsen, Daniel; Rosenberg, Edward; Gobetto, Roberto; Viale, Alessandra; Burton, Sarah D.; Ferel, Joseph

    2006-09-13

    Silanization of the silica gel surface in the synthesis of silica gel polyamine composites uses (chloropropyl)-trichlorosilane (CPTCS). It is possible to substitute a molar fraction of reagent CPTCS with methyltrichlorosilane (MTCS), creating a mixed silane surface layer. Two types of silica gels were modified with a series of MTCS:CPTCS molar ratios. Solid-state CP/MAS 29Si and 13C NMR spectroscopies were used to evaluate the surface silane composition. Surface silane coverage was markedly improved for the resulting gels. When polyamines were grafted to the resultant MTCS:CPTCS silane layers, it was shown that the decrease in the number of propyl attachments to the polyamine resulted in increased quantities of ''free amines''. Optimum MTCS:CPTCS ratios were determined for three polyamines grafted onto one silica gel. A substantial free amine increase was observed for poly(allylamine) (PAA). Metal uptake studies show increases in Cu(II) capacity and/or an improvement in Cu(II) mass-transfer kinetics. The effect of polymer molecular weight upon Cu(II) capacity was investigated for each polyamine. Substantial differences in Cu(II) capacity between 50,000 MW poly(vinylamine) (PVA) and >1000 MW PVA were evident. Similar differences between 25,000 MW poly(ethyleneimine) (PEI) and 1200 MW PEI were found. The mass-transfer kinetics was shown to be improved for composites prepared using a large fraction of MTCS in the reagent silane mixture. This resulted in substantial improvements in the 10% breakthrough Cu(II) capacity for PVA (50 000 MW). PEI composites were further modified to form an amino-acetate ligand. The impact of the MTCS:CPTCS silane ratio on the acetate ligand loading and ultimately on the Cu(II) capacity at pH 2 was investigated. A ratio of 12.5:1 was shown to result in an acetate modified PEI composite with a Cu(II) capacity 140% of the Cu(II) capacity of the same composite prepared with ''CPTCS only''.

  7. Stabilisation of proteins via mixtures of amino acids during spray drying.

    PubMed

    Ajmera, Ankur; Scherließ, Regina

    2014-03-10

    Biologicals are often formulated as solids in an effort to preserve stability which generally requires stabilising excipients for proper drying. The purpose of this study was to screen amino acids and their combinations for their stabilising effect on proteins during spray drying. Catalase, as model protein, was spray dried in 1+1 or 1+2 ratios with amino acids. Some amino acids namely arginine, glycine and histidine showed good retention of catalase functionality after spray drying and subsequent storage stress. A 1+1 combination of arginine and glycine in a 1+2 ratio with catalase resulted in a tremendously good stabilising effect. Storage at high temperature/humidity also showed beneficial effects of this combination. To evaluate whether this was a general principle, these findings were transferred to an antigenic protein of comparable size and supramolecular structure (haemagglutinin) as well as to a smaller enzyme (lysozyme). Upon spray drying with the combination of amino acids it could be shown that both proteins remain more stable especially after storage compared to the unprotected protein. The combination of arginine and glycine is tailored to the needs of protein stabilisation during spray drying and may hence be utilised in dry powder formulation of biomolecules with superior stability characteristics.

  8. Effects of high-melting methyl esters on crystallization properties of fatty acid methyl ester mixtures

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Biodiesel is a renewable alternative diesel fuel made from vegetable oils and animal fats. The most common form of biodiesel in the United States are fatty acid methyl esters (FAME) from soybean, canola, and used cooking oils, waste greases, and tallow. Cold flow properties of biodiesel depend on th...

  9. Nitric acid-organic mixtures surveyed for use in separation by anion exchange methods

    NASA Technical Reports Server (NTRS)

    Bloomquist, C. A. A.; Faris, J. P.; Stewart, D. C.

    1968-01-01

    Column elution-spectrographic analysis technique compares certain solvents directly to the methanol system, using inert rare earths instead of actinides. Distribution ratios for americium between 90 percent solvent, 10 percent 5 M nitric acid and Dowex 1 nitrate form resin for a large group of organics miscible in water was determined.

  10. Hormones, polyamines, and cell wall metabolism during oil palm fruit mesocarp development and ripening.

    PubMed

    Teh, Huey Fang; Neoh, Bee Keat; Wong, Yick Ching; Kwong, Qi Bin; Ooi, Tony Eng Keong; Ng, Theresa Lee Mei; Tiong, Soon Huat; Low, Jaime Yoke Sum; Danial, Asma Dazni; Ersad, Mohd Amiron; Kulaveerasingam, Harikrishna; Appleton, David R

    2014-08-13

    Oil palm is one of the most productive oil-producing crops and can store up to 90% oil in its fruit mesocarp. Oil palm fruit is a sessile drupe consisting of a fleshy mesocarp from which palm oil is extracted. Biochemical changes in the mesocarp cell walls, polyamines, and hormones at different ripening stages of oil palm fruits were studied, and the relationship between the structural and the biochemical metabolism of oil palm fruits during ripening is discussed. Time-course analysis of the changes in expression of polyamines, hormones, and cell-wall-related genes and metabolites provided insights into the complex processes and interactions involved in fruit development. Overall, a strong reduction in auxin-responsive gene expression was observed from 18 to 22 weeks after pollination. High polyamine concentrations coincided with fruit enlargement during lipid accumulation and latter stages of maturation. The trend of abscisic acid (ABA) concentration was concordant with GA₄ but opposite to the GA₃ profile such that as ABA levels increase the resulting elevated ABA/GA₃ ratio clearly coincides with maturation. Polygalacturonase, expansin, and actin gene expressions were also observed to increase during fruit maturation. The identification of the master regulators of these coordinated processes may allow screening for oil palm variants with altered ripening profiles.

  11. Conjugation with polyamines enhances the antibacterial and anticancer activity of chloramphenicol

    PubMed Central

    Kostopoulou, Ourania N.; Kouvela, Ekaterini C.; Magoulas, George E.; Garnelis, Thomas; Panagoulias, Ioannis; Rodi, Maria; Papadopoulos, Georgios; Mouzaki, Athanasia; Dinos, George P.; Papaioannou, Dionissios; Kalpaxis, Dimitrios L.

    2014-01-01

    Chloramphenicol (CAM) is a broad-spectrum antibiotic, limited to occasional only use in developed countries because of its potential toxicity. To explore the influence of polyamines on the uptake and activity of CAM into cells, a series of polyamine–CAM conjugates were synthesized. Both polyamine architecture and the position of CAM-scaffold substitution were crucial in augmenting the antibacterial and anticancer potency of the synthesized conjugates. Compounds 4 and 5, prepared by replacement of dichloro-acetyl group of CAM with succinic acid attached to N4 and N1 positions of N8,N8-dibenzylspermidine, respectively, exhibited higher activity than CAM in inhibiting the puromycin reaction in a bacterial cell-free system. Kinetic and footprinting analysis revealed that whereas the CAM-scaffold preserved its role in competing with the binding of aminoacyl-tRNA 3′-terminus to ribosomal A-site, the polyamine-tail could interfere with the rotatory motion of aminoacyl-tRNA 3′-terminus toward the P-site. Compared to CAM, compounds 4 and 5 exhibited comparable or improved antibacterial activity, particularly against CAM-resistant strains. Compound 4 also possessed enhanced toxicity against human cancer cells, and lower toxicity against healthy human cells. Thus, the designed conjugates proved to be suitable tools in investigating the ribosomal catalytic center plasticity and some of them exhibited greater efficacy than CAM itself. PMID:24939899

  12. Perturbation of polyamine catabolism affects grape ripening of Vitis vinifera cv. Trincadeira.

    PubMed

    Agudelo-Romero, Patricia; Ali, Kashif; Choi, Young H; Sousa, Lisete; Verpoorte, Rob; Tiburcio, Antonio F; Fortes, Ana M

    2014-01-01

    Grapes are economically the most important fruit worldwide. However, the complexity of biological events that lead to ripening of nonclimacteric fruits is not fully understood, particularly the role of polyamines' catabolism. The transcriptional and metabolic profilings complemented with biochemical data were studied during ripening of Trincadeira grapes submitted to guazatine treatment, a potent inhibitor of polyamine oxidase activity. The mRNA expression profiles of one time point (EL 38) corresponding to harvest stage was compared between mock and guazatine treatments using Affymetrix GrapeGen(®) genome array. A total of 2113 probesets (1880 unigenes) were differentially expressed between these samples. Quantitative RT-PCR validated microarrays results being carried out for EL 35 (véraison berries), EL 36 (ripe berries) and EL 38 (harvest stage berries). Metabolic profiling using HPLC and (1)H NMR spectroscopy showed increase of putrescine, proline, threonine and 1-O-ethyl-β-glucoside in guazatine treated samples. Genes involved in amino acid, carbohydrate and water transport were down-regulated in guazatine treated samples suggesting that the strong dehydrated phenotype obtained in guazatine treated samples may be due to impaired transport mechanisms. Genes involved in terpenes' metabolism were differentially expressed between guazatine and mock treated samples. Altogether, results support an important role of polyamine catabolism in grape ripening namely in cell expansion and aroma development.

  13. Discovery of novel polyamine analogs with anti-protozoal activity by computer guided drug repositioning

    NASA Astrophysics Data System (ADS)

    Alberca, Lucas N.; Sbaraglini, María L.; Balcazar, Darío; Fraccaroli, Laura; Carrillo, Carolina; Medeiros, Andrea; Benitez, Diego; Comini, Marcelo; Talevi, Alan

    2016-04-01

    Chagas disease is a parasitic infection caused by the protozoa Trypanosoma cruzi that affects about 6 million people in Latin America. Despite its sanitary importance, there are currently only two drugs available for treatment: benznidazole and nifurtimox, both exhibiting serious adverse effects and limited efficacy in the chronic stage of the disease. Polyamines are ubiquitous to all living organisms where they participate in multiple basic functions such as biosynthesis of nucleic acids and proteins, proliferation and cell differentiation. T. cruzi is auxotroph for polyamines, which are taken up from the extracellular medium by efficient transporters and, to a large extent, incorporated into trypanothione (bis-glutathionylspermidine), the major redox cosubstrate of trypanosomatids. From a 268-compound database containing polyamine analogs with and without inhibitory effect on T. cruzi we have inferred classificatory models that were later applied in a virtual screening campaign to identify anti-trypanosomal compounds among drugs already used for other therapeutic indications (i.e. computer-guided drug repositioning) compiled in the DrugBank and Sweetlead databases. Five of the candidates identified with this strategy were evaluated in cellular models from different pathogenic trypanosomatids ( T. cruzi wt, T. cruzi PAT12, T. brucei and Leishmania infantum), and in vitro models of aminoacid/polyamine transport assays and trypanothione synthetase inhibition assay. Triclabendazole, sertaconazole and paroxetine displayed inhibitory effects on the proliferation of T. cruzi (epimastigotes) and the uptake of putrescine by the parasite. They also interfered with the uptake of others aminoacids and the proliferation of infective T. brucei and L. infantum (promastigotes). Trypanothione synthetase was ruled out as molecular target for the anti-parasitic activity of these compounds.

  14. Effects of polyamines on prostatic chromatin- and non-histone-protein-associated protein kinase reactions.

    PubMed Central

    Ahmed, K; Wilson, M J; Goueli, S A; Williams-Ashman, H G

    1978-01-01

    Studies are presented on the influence of polyamines on prostatic chromatin- and non-histone-protein-associated protein kinase reactions involving both exogenous and endogenous substrates. The activities toward the model acidic protein substrate, dephosphophosvitin, were maximal at 160--200mM-NaCl (or -KCl or -NH4Cl). Under these conditions, spermidine and spermine added in concentrations up to 2mM were essentially without effect. However, without addition of NaCl to the medium, marked stimulation of these reactions was elicited by these polyamines at 1--2mM concentrations. The stimulatory effects were not due to non-specific changes in the ionic strength or to substitution of spermine for Mg2+, as maximal stimulation by 1 mM-spermine was observed only at optimal (2--4mM) Mg2+ concentrations. Qualitatively similar effects of polyamines were observed with enzyme preparations from the prostates of castrated rats, and with chromatin and non-histone-protein preparations from other tissues besides ventral prostate. When phosphorylation of endogenous non-histone proteins of the chromatin was measured, spermine stimulated both the initial rates and the final extent of transphosphorylation, even in the presence of optimal concentration of NaCl. By contrast, spermine or spermidine had no effect on the chromatin- and non-histone-protein-associated protein kinase reactions determined with lysine-rich histones as substrates. Chemically NN-dimethylated dephosphophosvitin was a less active substrate for the chromatin-associated protein kinase, but its phosphorylation was more markedly stimulated by spermine in comparison with unmodified dephosphophosvitin. These observations hint that the polyamine stimulations of the various protein kinase reactions may be due to effects on the conformations of the non-histone protein substrates rather than on the kinases themselves. PMID:747650

  15. Enhancement of myofibrillar proteolysis following infusion of amino acid mixture correlates positively with elevation of core body temperature in rats.

    PubMed

    Yamaoka, Ippei; Mikura, Mayumi; Nishimura, Masuhiro; Doi, Masako; Kawano, Yuichi; Nakayama, Mitsuo

    2008-12-01

    Administration of an amino acid (AA) mixture stimulates muscle protein synthesis and elevates core body temperature (T(b)), as characteristically found under anesthetic conditions. We tested the hypothesis that not only AA given, but also AA produced by degradation of endogenous muscular protein are provided for muscle protein synthesis, which is further reflected in T(b) modifications. Rats were intravenously administered an AA mixture or saline in combination with the anesthetic propofol or lipid emulsion. We measured plasma 3-methylhistidine (MeHis) concentrations as an index of myofibrillar protein degradation, rectal temperature and mRNA expression of atrogin-1, MuRF-1 and ubiquitin in gastrocnemius and soleus muscles of rats following 3 h infusion of test solutions. T(b) did not differ significantly between conscious groups, but was higher in the AA group than in the saline group among anesthetized rats. Plasma MeHis concentrations were higher in the AA group than in the saline group under both conditions. Plasma MeHis levels correlated positively with T(b) of rats under both conditions. AA administration decreased mRNA levels of atrogin-1 and ubiquitin in gastrocnemius muscle and all mRNA levels in soleus muscle. These results suggest that AA administration enhances myofibrillar protein degradation and that the change is a determinant of T(b) modification by AA administration. However, the mechanisms underlying AA administration-associated enhancement of myofibrillar proteolysis remains yet to be determined.

  16. High-performance liquid chromatographic determination of polyamines in milk as their 9-fluorenylmethoxycarbonyl derivatives using a column-switching technique.

    PubMed

    Bellagamba, F; Moretti, V M; Mentasti, T; Albertini, A; Luzzana, U; Valfrè, F

    1997-12-12

    A high-performance liquid chromatographic method for the determination of polyamines in milk is milk is described. Polyamines were extracted in perchloric acid and derivatized with 9-fluorenylmethoxycarbonyl chloride (FMOC-Cl). The excess of reagent was reacted with aspartic acid before the analysis on a column-switching system. Linearity of derivatization was calculated for each amine and the coefficient of regression ranged from 0.994 to 0.999. Chromatographic separation of FMOC-polyamines was achieved with a gradient elution programme of water-acetonitrile. The correlation coefficients of the standard curves in the concentration range from 0.5 to 5 nmol ml-1 were higher than 0.991. The repeatability of the method, expressed as R.S.D. for each polyamines ranged from 3.0 to 8.6%. The percent mean recoveries at 1 nmol ml-1 spiking level were 49 +/- 3, 58 +/- 5, 61 +/- 5 and 48 +/- 4 for putrescine, cadaverine, spermidine and spermine, respectively. The limit of detection, calculated on the basis of three times signal-to-noise ratio, was 50 pmol ml-1 for each polyamine.

  17. Electrochemical method for producing a biodiesel mixture comprising fatty acid alkyl esters and glycerol

    DOEpatents

    Lin, YuPo J; St. Martin, Edward J

    2013-08-13

    The present invention relates to an integrated method and system for the simultaneous production of biodiesel from free fatty acids (via esterification) and from triglycerides (via transesterification) within the same reaction chamber. More specifically, one preferred embodiment of the invention relates to a method and system for the production of biodiesel using an electrodeionization stack, wherein an ion exchange resin matrix acts as a heterogeneous catalyst for simultaneous esterification and transesterification reactions between a feedstock and a lower alcohol to produce biodiesel, wherein the feedstock contains significant levels of free fatty acid. In addition, because of the use of a heterogeneous catalyst, the glycerol and biodiesel have much lower salt concentrations than raw biodiesel produced by conventional transesterification processes. The present invention makes it much easier to purify glycerol and biodiesel.

  18. Catalytic Hydrotreatment of Humins in Mixtures of Formic Acid/2-Propanol with Supported Ruthenium Catalysts.

    PubMed

    Wang, Yuehu; Agarwal, Shilpa; Kloekhorst, Arjan; Heeres, Hero Jan

    2016-05-10

    The catalytic hydrotreatment of humins, which are the solid byproducts from the conversion of C6 sugars (glucose, fructose) into 5-hydroxymethylfurfural (HMF) and levulinic acid (LA), by using supported ruthenium catalysts has been investigated. Reactions were carried out in a batch setup at elevated temperatures (400 °C) by using a hydrogen donor (formic acid (FA) in isopropanol (IPA) or hydrogen gas), with humins obtained from d-glucose. Humin conversions of up to 69 % were achieved with Ru/C and FA, whereas the performance for Ru on alumina was slightly poorer (59 % humin conversion). Humin oils were characterized by using a range of analytical techniques (GC, GC-MS, GCxGC, gel permeation chromatography) and were shown to consist of monomers, mainly alkyl phenolics (>45 % based on compounds detectable by GC) and higher oligomers. A reaction network for the reaction is proposed based on structural proposals for humins and the main reaction products.

  19. Inhibition of corneal neovascularization with a nutrient mixture containing lysine, proline, ascorbic acid, and green tea extract.

    PubMed

    Shakiba, Yadollah; Mostafaie, Ali

    2007-10-01

    Corneal neovascularization is a significant, sight-threatening complication of many ocular surface disorders. Various growth factors and proteinases are involved in corneal neovascularization. The data supporting a causal role for vascular endothelial growth factor (VEGF) and matrix metalloproteinases (MMPs) are extensive. Inhibition of VEGF and MMPs is a main strategy for treating corneal neovascularization. Several findings have shown that corneal neovascularization can be reduced by using anti-VEGF and anti-MMPs agents. Efficacy of a nutrient mixture (NM) containing lysine, proline, ascorbic acid, and green tea extract has been demonstrated for reducing VEGF and MMPs secretion by various cells. Moreover, NM can inhibit endothelial cell migration and capillary tube formation. We herein note that topical application of NM is potentially useful for inhibiting corneal neovascularization and restoration of corneal clarity. Further investigations in animal models are needed to place NM alongside corneal neovascularization therapeutics.

  20. Soft cutting of single-wall carbon nanotubes by low temperature ultrasonication in a mixture of sulfuric and nitric acids

    NASA Astrophysics Data System (ADS)

    Shuba, M. V.; Paddubskaya, A. G.; Kuzhir, P. P.; Maksimenko, S. A.; Ksenevich, V. K.; Niaura, G.; Seliuta, D.; Kasalynas, I.; Valusis, G.

    2012-12-01

    To decrease single-wall carbon nanotube (SWCNT) lengths to a value of 100-200 nm, aggressive cutting methods, accompanied by a high loss of starting material, are frequently used. We propose a cutting approach based on low temperature intensive ultrasonication in a mixture of sulfuric and nitric acids. The method is nondestructive with a yield close to 100%. It was applied to cut nanotubes produced in three different ways: gas-phase catalysis, chemical vapor deposition, and electric-arc-discharge methods. Raman and Fourier transform infrared spectroscopy were used to demonstrate that the cut carbon nanotubes have a low extent of sidewall degradation and their electronic properties are close to those of the untreated tubes. It was proposed to use the spectral position of the far-infrared absorption peak as a simple criterion for the estimation of SWCNT length distribution in the samples.

  1. Soft cutting of single-wall carbon nanotubes by low temperature ultrasonication in a mixture of sulfuric and nitric acids.

    PubMed

    Shuba, M V; Paddubskaya, A G; Kuzhir, P P; Maksimenko, S A; Ksenevich, V K; Niaura, G; Seliuta, D; Kasalynas, I; Valusis, G

    2012-12-14

    To decrease single-wall carbon nanotube (SWCNT) lengths to a value of 100-200 nm, aggressive cutting methods, accompanied by a high loss of starting material, are frequently used. We propose a cutting approach based on low temperature intensive ultrasonication in a mixture of sulfuric and nitric acids. The method is nondestructive with a yield close to 100%. It was applied to cut nanotubes produced in three different ways: gas-phase catalysis, chemical vapor deposition, and electric-arc-discharge methods. Raman and Fourier transform infrared spectroscopy were used to demonstrate that the cut carbon nanotubes have a low extent of sidewall degradation and their electronic properties are close to those of the untreated tubes. It was proposed to use the spectral position of the far-infrared absorption peak as a simple criterion for the estimation of SWCNT length distribution in the samples.

  2. Growth of Chlorella sorokiniana on a mixture of volatile fatty acids: The effects of light and temperature.

    PubMed

    Turon, V; Trably, E; Fouilland, E; Steyer, J-P

    2015-12-01

    This study investigated the influence of light and temperature on Chlorella sorokiniana grown on a mixture of acetate and butyrate, two of the volatile fatty acids produced by dark fermentation. Exposure to light caused autotrophic biomass production (56% of the final biomass) and reduced the time to reach butyrate exhaustion to 7 days at 25°C from 10 days in the dark. For growth on acetate at the optimum temperature (35°C), the presence of butyrate reduced the growth rate (by 46%) and the carbon yield (by 36%). For successful microalgae growth on dark fermentation effluent, butyrate inhibition may be reduced by setting the temperature to 30°C and providing light.

  3. Voltammetric determination of mixtures of caffeine and chlorogenic acid in beverage samples using a boron-doped diamond electrode.

    PubMed

    Yardım, Yavuz; Keskin, Ertugrul; Şentürk, Zühre

    2013-11-15

    Herein, a boron-doped diamond (BDD) electrode that is anodically pretreated was used for the simultaneous determination of caffeine (CAF) and chlorogenic acid (CGA) by cyclic and adsorptive stripping voltammetry. The dependence of peak current and potential on pH, scan rate, accumulation parameters and other experimental variables were studied. By using square-wave stripping mode after 60 s accumulation under open-circuit voltage, the BDD electrode was able to separate the oxidation peak potentials of CAF and CGA present in binary mixtures by about 0.4V in Britton-Robinson buffer at pH 1.0. The limits of detection were 0.107 µg mL(-1) (5.51×10(-7) M) for CAF, and 0.448 µg mL(-1) (1.26×10(-6) M) for CGA. The practical applicability of this methodology was tested in commercially available beverage samples.

  4. Method and compositions for reducing corrosion in the removal of acidic gases from gaseous mixtures

    SciTech Connect

    DuPart, M.S.; Cringle, D.C.; Oakes, B.D.

    1984-05-01

    A corrosion inhibited composition containing a gas conditioning solution such as an alkanol amine with water or with organic solvents and with small amounts of soluble thiocyanate compounds, soluble trivalent bismuth compounds with or without soluble divalent nickel or cobalt compounds. The compositions are useful to separate acid gases such as carbon dioxide from hydrocarbon feed streams in gas conditioning apparatus with minimum amounts of corrosion of the ferrous surfaces.

  5. Improving enzymatic hydrolysis of corn stover pretreated by ethylene glycol-perchloric acid-water mixture.

    PubMed

    He, Yu-Cai; Liu, Feng; Gong, Lei; Lu, Ting; Ding, Yun; Zhang, Dan-Ping; Qing, Qing; Zhang, Yue

    2015-02-01

    To improve the enzymatic saccharification of lignocellulosic biomass, a mixture of ethylene glycol-HClO4-water (88.8:1.2:10, w/w/w) was used for pretreating corn stover in this study. After the optimization in oil-bath system, the optimum pretreatment temperature and time were 130 °C and 30 min, respectively. After the saccharification of 10 g/L pretreated corn stover for 48 h, the saccharification rate was obtained in the yield of 77.4 %. To decrease pretreatment temperature and shorten pretreatment time, ethylene glycol-HClO4-water (88.8:1.2:10, w/w/w) media under microwave irradiation was employed to pretreat corn stover effectively at 100 °C and 200 W for 5 min. Finally, the recovered hydrolyzates containing glucose obtained from the enzymatic hydrolysis of pretreated corn stovers could be fermented into ethanol efficiently. These results would be helpful for developing a cost-effective pretreatment combined with enzymatic saccharification of cellulosic materials for the production of lignocellulosic ethanol.

  6. Comparison of Intradialytic Parenteral Nutrition with Glucose or Amino Acid Mixtures in Maintenance Hemodialysis Patients

    PubMed Central

    Liu, Yan; Xiao, Xiao; Qin, Dan-Ping; Tan, Rong-Shao; Zhong, Xiao-Shi; Zhou, Dao-Yuan; Liu, Yun; Xiong, Xuan; Zheng, Yuan-Yuan

    2016-01-01

    Many long-term maintenance hemodialysis patients have symptoms of protein-energy wasting caused by malnutrition. Each session of hemodialysis removes about 10 to 12 g of amino acids and 200 to 480 kcal of energy. Patients receiving hemodialysis for chronic kidney disease may be undernourished for energy, protein consumption, or both. Non-diabetic hemodialysis patients were randomized to three treatment groups: oral supplementation, oral supplementation plus high-concentration glucose solution (250 mL containing 50% glucose) and these two interventions plus 8.5% amino acids solution. The post-treatment energy status of the glucose group was significantly higher than its baseline level, whereas the control group’s status was significantly lower. The glucose group had significantly higher concentrations of asparagine, glutamine, glycine, alanine, and lysine after treatment. All treatment groups had significantly increased hemoglobin levels but significantly decreased transferrin levels after treatment compared to baseline. After treatment, the amino acid group had significantly higher albumin level compared to the glucose group (p = 0.001) and significantly higher prealbumin level compared to the control group (p = 0.017). In conclusion, long-term intervention with high-concentration glucose solution at each hemodialysis session is a simple and cheap method that replenished energy stores lost during hemodialysis of non-diabetic patients. PMID:27271658

  7. Comparison of Intradialytic Parenteral Nutrition with Glucose or Amino Acid Mixtures in Maintenance Hemodialysis Patients.

    PubMed

    Liu, Yan; Xiao, Xiao; Qin, Dan-Ping; Tan, Rong-Shao; Zhong, Xiao-Shi; Zhou, Dao-Yuan; Liu, Yun; Xiong, Xuan; Zheng, Yuan-Yuan

    2016-06-02

    Many long-term maintenance hemodialysis patients have symptoms of protein-energy wasting caused by malnutrition. Each session of hemodialysis removes about 10 to 12 g of amino acids and 200 to 480 kcal of energy. Patients receiving hemodialysis for chronic kidney disease may be undernourished for energy, protein consumption, or both. Non-diabetic hemodialysis patients were randomized to three treatment groups: oral supplementation, oral supplementation plus high-concentration glucose solution (250 mL containing 50% glucose) and these two interventions plus 8.5% amino acids solution. The post-treatment energy status of the glucose group was significantly higher than its baseline level, whereas the control group's status was significantly lower. The glucose group had significantly higher concentrations of asparagine, glutamine, glycine, alanine, and lysine after treatment. All treatment groups had significantly increased hemoglobin levels but significantly decreased transferrin levels after treatment compared to baseline. After treatment, the amino acid group had significantly higher albumin level compared to the glucose group (p = 0.001) and significantly higher prealbumin level compared to the control group (p = 0.017). In conclusion, long-term intervention with high-concentration glucose solution at each hemodialysis session is a simple and cheap method that replenished energy stores lost during hemodialysis of non-diabetic patients.

  8. Selective precipitation of ribonucleic acid from a mixture of total cellular nucleic acids extracted from cultured mammalian cells

    PubMed Central

    Harrison, P. R.

    1971-01-01

    A simple and reproducible method is described for precipitating RNA selectively from total mammalian-cell nucleic acids extracted by the phenol–sodium dodecyl sulphate procedure at pH8.0. Under specified conditions bulk RNA is precipitated almost quantitatively whereas bulk DNA remains in solution. Minor components of RNA (detected by pulse-labelling and chromatography on methylated albumin–kieselguhr) and rapidly labelled components of DNA containing single-stranded regions are also precipitated. The usefulness of the method is discussed in the context of isolating separately both RNA and DNA from cultured cells that are difficult to obtain in quantity. PMID:5165620

  9. Polyamines release the let-7b-mediated suppression of initiation codon recognition during the protein synthesis of EXT2

    PubMed Central

    Imamura, Masataka; Higashi, Kyohei; Yamaguchi, Katsutoshi; Asakura, Kiryu; Furihata, Tomomi; Terui, Yusuke; Satake, Toshihiko; Maegawa, Jiro; Yasumura, Kazunori; Ibuki, Ai; Akase, Tomoko; Nishimura, Kazuhiro; Kashiwagi, Keiko; Linhardt, Robert J.; Igarashi, Kazuei; Toida, Toshihiko

    2016-01-01

    Proteoglycans (PGs), a family of glycosaminoglycan (GAG)-protein glycoconjugates, contribute to animal physiology through interactions between their glycan chains and growth factors, chemokines and adhesion molecules. However, it remains unclear how GAG structures are changed during the aging process. Here, we found that polyamine levels are correlated with the expression level of heparan sulfate (HS) in human skin. In cultured cell lines, the EXT1 and EXT2 enzymes, initiating HS biosynthesis, were stimulated at the translational level by polyamines. Interestingly, the initiation codon recognition by 43S preinitiation complex during EXT2 translation is suppressed by let-7b, a member of the let-7 microRNA family, through binding at the N-terminal amino acid coding sequence in EXT2 mRNA. Let-7b-mediated suppression of initiation codon depends on the length of 5′-UTR of EXT2 mRNA and its suppression is inhibited in the presence of polyamines. These findings provide new insights into the HS biosynthesis related to miRNA and polyamines. PMID:27650265

  10. A Nascent Peptide Signal Responsive to Endogenous Levels of Polyamines Acts to Stimulate Regulatory Frameshifting on Antizyme mRNA.

    PubMed

    Yordanova, Martina M; Wu, Cheng; Andreev, Dmitry E; Sachs, Matthew S; Atkins, John F

    2015-07-17

    The protein antizyme is a negative regulator of cellular polyamine concentrations from yeast to mammals. Synthesis of functional antizyme requires programmed +1 ribosomal frameshifting at the 3' end of the first of two partially overlapping ORFs. The frameshift is the sensor and effector in an autoregulatory circuit. Except for Saccharomyces cerevisiae antizyme mRNA, the frameshift site alone only supports low levels of frameshifting. The high levels usually observed depend on the presence of cis-acting stimulatory elements located 5' and 3' of the frameshift site. Antizyme genes from different evolutionary branches have evolved different stimulatory elements. Prior and new multiple alignments of fungal antizyme mRNA sequences from the Agaricomycetes class of Basidiomycota show a distinct pattern of conservation 5' of the frameshift site consistent with a function at the amino acid level. As shown here when tested in Schizosaccharomyces pombe and mammalian HEK293T cells, the 5' part of this conserved sequence acts at the nascent peptide level to stimulate the frameshifting, without involving stalling detectable by toe-printing. However, the peptide is only part of the signal. The 3' part of the stimulator functions largely independently and acts at least mostly at the nucleotide level. When polyamine levels were varied, the stimulatory effect was seen to be especially responsive in the endogenous polyamine concentration range, and this effect may be more general. A conserved RNA secondary structure 3' of the frameshift site has weaker stimulatory and polyamine sensitizing effects on frameshifting.

  11. Antineoplastic Efficacy of Novel Polyamine Analogues in Human Breast Cancer

    DTIC Science & Technology

    2007-06-01

    Principles of Molecular Medicine (2nd ed). Runge, M., and Patterson, WC. (eds), Humana Press, 2006. 2. Huang, Y., Pledgie A.M., Casero , R.A., Davidson...Dunn, V.R., Hacker, A., Frydman, B., Kink J.A., Valasinas, A.L., Reddy, V.K., Marton, L.J., Casero , R.A., and Davidson, N.E. A Novel Polyamine...E.R., Smith, R., Frydman, B., Valasinas, A.L., Reddy, V.K., Marton, L.J., Casero , R.A., and Davidson, N.E. Regulation of polyamine analogue

  12. Effect of Acidic Environment on the Push-Out Bond Strength of Calcium-Enriched Mixture Cement

    PubMed Central

    Sobhnamayan, Fereshte; Sahebi, Safoora; Naderi, Misagh; Shojaee, Nooshin Sadat; Shanbezadeh, Najmeh

    2014-01-01

    Introduction: This laboratory study was performed to evaluate the effect of different acidic pH values on the push-out bond strength of calcium-enriched mixture (CEM) cement. Methods and Materials: Forty-eight root dentin slices were obtained from freshly extracted single rooted human teeth and their lumen were instrumented to achieve a diameter of 1.3 mm. Then, CEM cement was mixed according to manufacturers’ instruction and placed in the lumens with minimal pressure. The specimens were randomly divided into four groups (n=12) which were wrapped in pieces of gauze soaked in either synthetic tissue fluid (STF) (pH=7.4) or butyric acid which was buffered at pH values of 4.4, 5.4 and 6.4. They were then incubated for 4 days at 37°C. The push-out test was performed by means of the universal testing machine. Specimens were then examined under a digital light microscope at 20× magnification to determine the nature of the bond failure. The data were analyzed using the Kruskal-Wallis test followed by Dunn’s test for pairwise comparisons. Results: The highest push-out bond strength (10.19±4.39) was seen in the pH level of 6.4, which was significantly different from the other groups (P<0.05). The values decreased to 2.42±2.25 MPa after exposure to pH value of 4.4. Conclusion: Lower pH value of highly acidic environments (pH=4.4), adversely affects the force needed for displacement of CEM cement; while in higher pH values (pH=6.4) the bond-strength was not affected. CEM cement is recommended in clinical situations where exposure to acidic environment is unavoidable. PMID:25386207

  13. A process for separating acid-sugar mixtures using ion exclusion chromatography

    SciTech Connect

    Hester, R.D.; Hartfield, S.W.; Farina, G.E.

    1994-10-01

    Work using a low-temperature concentrated sulfuric acid hydrolysis process to convert the cellulosic fraction of corn stover to monomeric sugars demonstrated the high conversion efficiencies possible with that process. The TVA work also confirmed the need for a cost-effective acid-sugar separation process. A preparative-scale ion-exclusion chromatography (IEC) system was designed, constructed, and tested with a variety of synthetic solutions and actual hydrolyzates. Although significant dispersion was observed initially, design changes were effective in minimizing this phenomenon. Data collected during the operation of the preparative-scale system were used in the design and construction of an IEC miniplant capable of processing larger volumes of synthetic solutions or hydrolyzates and in the design of an extraction-assisted IEC system. The data were also used to assess the viability of a continuous feed IEC system. This paper includes a discussion of the IEC process, provides overall material balances for various IEC process scenarios, and presents a discussion on process economics.

  14. Effects of polyamines and polyamine biosynthetic inhibitors on mitotic activity of Allium cepa root tips.

    PubMed

    Unal, Meral; Palavan-Unsal, Narcin; Tufekci, M A

    2008-03-01

    The genotoxic and cytotoxic effects of exogenous polyamines (PAs), putrescine (Put), spermidine (Spd), spermine (Spm) and PA biosynthetic inhibitors, alpha-difluoromethylornithine (DFMO), cyclohexilamine (CHA), methylglioxal bis-(guanylhydrazone) (MGBG) were investigated in the root meristems of Allium cepa L. The reduction of mitotic index and the induction of chromosomal aberrations such as bridges, stickiness, c-mitotic anaphases, micronuclei, endoredupliction by PAs and PA biosynthetic inhibitors were observed and these were used as evidence of genotoxicity and cytotoxicity.

  15. Mixture-amount design and response surface modeling to assess the effects of flavonoids and phenolic acids on developmental performance of Anastrepha ludens.

    PubMed

    Pascacio-Villafán, Carlos; Lapointe, Stephen; Williams, Trevor; Sivinski, John; Niedz, Randall; Aluja, Martín

    2014-03-01

    Host plant resistance to insect attack and expansion of insect pests to novel hosts may to be modulated by phenolic compounds in host plants. Many studies have evaluated the role of phenolics in host plant resistance and the effect of phenolics on herbivore performance, but few studies have tested the joint effect of several compounds. Here, we used mixture-amount experimental design and response surface modeling to study the effects of a variety of phenolic compounds on the development and survival of Mexican fruit fly (Anastrepha ludens [Loew]), a notorious polyphagous pest of fruit crops that is likely to expand its distribution range under climate change scenarios. (+)- Catechin, phloridzin, rutin, chlorogenic acid, and p-coumaric acid were added individually or in mixtures at different concentrations to a laboratory diet used to rear individuals of A. ludens. No effect was observed with any mixture or concentration on percent pupation, pupal weight, adult emergence, or survival from neonate larvae to adults. Larval weight, larval and pupal developmental time, and the prevalence of adult deformities were affected by particular mixtures and concentrations of the compounds tested. We suggest that some combinations/concentrations of phenolic compounds could contribute to the management of A. ludens. We also highlight the importance of testing mixtures of plant secondary compounds when exploring their effects upon insect herbivore performance, and we show that mixture-amount design is a useful tool for this type of experiments.

  16. Polyamine interactions with plant hormones: crosstalk at several levels

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Polyamines play important roles in diverse plant growth and development processes including seed germination, tissue lignification, organogenesis, flowering, pollination, embryogenesis, fruit development, ripening, abscission, senescence and stress responses. In all these processes, synergistic and ...

  17. Targeting polyamine metabolism for cancer therapy and prevention.

    PubMed

    Murray-Stewart, Tracy R; Woster, Patrick M; Casero, Robert A

    2016-10-01

    The chemically simple, biologically complex eukaryotic polyamines, spermidine and spermine, are positively charged alkylamines involved in many crucial cellular processes. Along with their diamine precursor putrescine, their normally high intracellular concentrations require fine attenuation by multiple regulatory mechanisms to keep these essential molecules within strict physiologic ranges. Since the metabolism of and requirement for polyamines are frequently dysregulated in neoplastic disease, the metabolic pathway and functions of polyamines provide rational drug targets; however, these targets have been difficult to exploit for chemotherapy. It is the goal of this article to review the latest findings in the field that demonstrate the potential utility of targeting the metabolism and function of polyamines as strategies for both chemotherapy and, possibly more importantly, chemoprevention.

  18. Properties of purified recombinant human polyamine oxidase, PAOh1/SMO.

    PubMed

    Wang, Yanlin; Murray-Stewart, Tracy; Devereux, Wendy; Hacker, Amy; Frydman, Benjamin; Woster, Patrick M; Casero, Robert A

    2003-05-16

    The discovery of an inducible oxidase whose apparent substrate preference is spermine indicates that polyamine catabolism is more complex than that originally proposed. To facilitate the study of this enzyme, the purification and characterization of the recombinant human PAOh1/SMO polyamine oxidase are reported. Purified PAOh1/SMO oxidizes both spermine (K(m)=1.6 microM) and N(1)-acetylspermine (K(m)=51 microM), but does not oxidize spermidine. The purified human enzyme also does not oxidize eight representative antitumor polyamine analogues; however, specific oligamine analogues were found to be potent inhibitors of the oxidation of spermine by PAOh1/SMO. The results of these studies are consistent with the hypothesis that PAOh1/SMO represents a new addition to the polyamine metabolic pathway that may represent a new target for antineoplastic drug development.

  19. Skin Carcinogenesis Studies Using Mouse Models with Altered Polyamines

    PubMed Central

    Nowotarski, Shannon L; Feith, David J; Shantz, Lisa M

    2015-01-01

    Nonmelanoma skin cancer (NMSC) is a major health concern worldwide. With increasing numbers in high-risk groups such as organ transplant recipients and patients taking photosensitizing medications, the incidence of NMSC continues to rise. Mouse models of NMSC allow us to better understand the molecular signaling cascades involved in skin tumor development in order to identify novel therapeutic strategies. Here we review the models designed to determine the role of the polyamines in NMSC development and maintenance. Elevated polyamines are absolutely required for tumor growth, and dysregulation of their biosynthetic and catabolic enzymes has been observed in NMSC. Studies using mice with genetic alterations in epidermal polyamines suggest that they play key roles in tumor promotion and epithelial cell survival pathways, and recent clinical trials indicate that pharmacological inhibitors of polyamine metabolism show promise in individuals at high risk for NMSC. PMID:26380554

  20. Cellular content and biosynthesis of polyamines during rooster spermatogenesis.

    PubMed Central

    Oliva, R; Vidal, S; Mezquita, C

    1982-01-01

    The natural polyamines spermine and spermidine, and the diamine putrescine, were extracted from rooster testis cells separated by sedimentation at unit gravity, and from vas-deferens spermatozoa. The ratios spermine/DNA and spermidine/DNA were kept relatively constant throughout spermatogenesis, whereas the ratio putrescine/DNA rose in elongated spermatids. The cellular content of spermine, spermidine and putrescine decreased markedly in mature spermatozoa. Two rate-limiting enzymes in the biosynthetic pathway of polyamines, ornithine decarboxylase and S-adenosyl-L-methionine decarboxylase, showed their highest activities at the end of spermiogenesis and were not detectable in vas-deferens spermatozoa. A marked reduction in cell volume during spermiogenesis without a parallel decrease in the cellular content of polyamines suggests the possibility that the marked changes in chromatin composition and structure occurring in rooster late spermatids could take place in an ambience of high polyamine concentration. Images PLATE 1 PMID:7159401

  1. Polyamines of primitive apterygotan insects: springtails, silverfish and a bristletail.

    PubMed

    Hamana, Koei; Uemiya, Hideyuki; Niitsu, Masaru

    2004-01-01

    Polyamines extracted from whole bodies of four springtails, Tomocerus ishibashii, Hypogastrura communis, Sinella cruviseta and Folsomia candida, a bristletail, Pedetontus nipponicus, and two silverfish, Lepisma saccharina and Thermobia domestica, were analyzed by high-performance liquid chromatography and gas chromatography. All seven apterous insect species contained putrescine, cadaverine and spermidine as the common major polyamines, detected at the level of micromol/g wet mass. T. ishibashii also contained spermine, S. cruviseta contained norspermidine and norspermine and H. communis, F. candida and P. nipponicus contained diaminopropane, norspermidine and norspermine, as minor polyamines above the detection limit (0.01 micromol/g wet mass). The occurrence of diaminopropane, norspermidine, norspermine, spermine and thermospermine was confirmed in L. saccharina and T. domestica. The novel polyamines norspermidine, norspermine and thermospermine, widespread in higher insects, were also distributed within the primitive apterygotan insects.

  2. EVALUATION OF THE JOINT TOXIC ACTION OF MIXTURES OF HALOACETIC ACIDS CONSTRUCTED USING ENVIRONMENTAL CONCENTRATION/EXPOSURE DATA

    EPA Science Inventory

    Disinfection byproducts (DBPs) are formed by reactions between chemicals used to disinfect water and organic compounds present in source water. The composition of DBP mixtures varies based on a number of factors, including treatment scenario, with different DBP mixtures contain...

  3. Binary mixtures of diclofenac with paracetamol, ibuprofen, naproxen, and acetylsalicylic acid and these pharmaceuticals in isolated form induce oxidative stress on Hyalella azteca.

    PubMed

    Gómez-Oliván, Leobardo Manuel; Neri-Cruz, Nadia; Galar-Martínez, Marcela; Islas-Flores, Hariz; García-Medina, Sandra

    2014-11-01

    Toxicity in natural ecosystems is usually not due to exposure to a single substance, but is rather the result of exposure to mixtures of toxic substances. Knowing the effects of contaminants as a mixture compared to their effects in isolated form is therefore important. This study aimed to evaluate the oxidative stress induced by binary mixtures of diclofenac with paracetamol, ibuprofen, naproxen, and acetylsalicylic acid and by these nonsteroidal anti-inflammatory drugs (NSAIDs) in isolated form, using Hyalella azteca as a bioindicator. The median lethal concentration (LC50) and the lowest observed adverse effect level (LOAEL) of each NSAID were obtained. Amphipods were exposed for 72 h to the latter value in isolated form and as binary mixtures. The following biomarkers were evaluated: lipid peroxidation (LPX), protein carbonyl content (PCC), and activity of the antioxidant enzymes: superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx). Significant increases in LPX and PCC with respect to the control group (p ≤ 0.05) were induced by NSAIDs both in isolated form and as binary mixtures. Changes in SOD, CAT, and GPx activity likewise occurred with NSAIDs in isolated form and as binary mixtures. In conclusion, NSAIDs used in this study induce oxidative stress on H. azteca both in isolated form and as binary mixtures, and the interactions occurring between these pharmaceuticals are probably antagonistic in type.

  4. Dendritic sidebranching with periodic localized perturbations: Directional solidification of pivalic acid--coumarin 152 mixtures

    SciTech Connect

    Williams, L.M.; Muschol, M.; Qian, X.; Losert, W.; Cummins, H.Z. )

    1993-07-01

    We have studied the response of the sidebranches of pivalic acid dendrites, growing by directional solidification, to localized periodic thermal perturbations. The perturbations were generated by a laser beam focused near the tip of a single dendrite growing in a glass capillary, with the pulse duration, repetition rate, and intensity controlled separately. The perturbation dramatically altered the sidebranch structure, producing ordered sidebranches of well-defined wavelength, synchronous with the perturbation, which were strongly correlated on the two sides of the dendrite. The dependencies of the sidebranch amplitude on the frequency of the perturbation and on the distance from the dendrite tip were compared to the predictions of Barber, Barbieri, and Langer [Phys. Rev. A 36, 3340 (1987)] and found to be in qualitative agreement. The value of the selection parameter [sigma] found from these fits to the theory is compared to a value obtained from material parameters also determined in this experiment, and to a value deduced from the initial Mullins-Sekerka instability of the planar crystal-melt interface.

  5. Influence of thermally processed carbohydrate/amino acid mixtures on the fermentation by Saccharomyces cerevisiae.

    PubMed

    Tauer, Andreas; Elss, Sandra; Frischmann, Matthias; Tellez, Patricia; Pischetsrieder, Monika

    2004-04-07

    The production of alcoholic beverages such as Tequila, Mezcal, whiskey, or beer includes the fermentation of a mash containing Maillard reaction products. Because excessive heating of the mash can lead to complications during the following fermentation step, the impact of Maillard products on the metabolism of Saccharomyces cerevisiae was investigated. For this purpose, fermentation was carried out in a model system in the presence and absence of Maillard reaction products and formation of ethanol served as a marker for the progression of fermentation. We found that increasing amounts of Maillard products reduced the formation of ethanol up to 80%. This effect was dependent on the pH value during the Maillard reaction, reaction time, as well as the carbohydrate and amino acid component used for the generation of Maillard reaction products. Another important factor is the pH value during fermentation: The inhibitory effect of Maillard products was not detectable at a pH of 4 and increased with higher pH-values. These findings might be of relevance for the production of above-mentioned beverages.

  6. Food polyamine and cardiovascular disease--an epidemiological study.

    PubMed

    Soda, Kuniyasu; Kano, Yoshihiko; Chiba, Fumihiro

    2012-09-28

    The purpose of this study was to examine the contribution of dietary polyamines toward preventing cardiovascular disease (CVD). Age-standardized mortality rates as well as other relevant information regarding individuals with CVD were gathered from the World Health Organization and the International Monetary Fund in 48 different European and other Western countries. Food supply data were collected from the database of the United Nations, and the amount of dietary polyamines was estimated by using polyamine concentrations in foods from published sources. The association between CVD mortality and the amount of polyamines was investigated by performing a series of multiple linear regression analyses. Analyses using factors known to modulate the risk of CVD including: Gross Domestic Product (GDP) (standardized regression coefficient (r) = -0.786, p < 0.001) and the amount of fruits, vegetable, nuts, and beans (r = -0.183, p = 0.001) but not including polyamines, showed negative associations with CVD, while smoking rate (r = 0.139, p = 0.041) and whole milk amount (r = 0.131, p = 0.028) showed positive associations with CVD. When the amount of polyamines was added to the analyses as a covariate, GDP (r = -0.864, p < 0.001) and polyamines (r = -0.355, p = 0.007) showed negative associations with CVD, while smoking rate (r = 0.183, p = 0.006) and whole milk (r = 0.113, p = 0.041) showed positive associations with CVD. The inverse association between dietary polyamines and CVD mortality revealed by the present study merits further evaluation.

  7. Polyamines Are Required for Virulence in Salmonella enterica Serovar Typhimurium

    PubMed Central

    Jelsbak, Lotte; Thomsen, Line Elnif; Wallrodt, Inke; Jensen, Peter Ruhdal; Olsen, John Elmerdahl

    2012-01-01

    Sensing and responding to environmental cues is a fundamental characteristic of bacterial physiology and virulence. Here we identify polyamines as novel environmental signals essential for virulence of Salmonella enterica serovar Typhimurium, a major intracellular pathogen and a model organism for studying typhoid fever. Central to its virulence are two major virulence loci Salmonella Pathogenicity Island 1 and 2 (SPI1 and SPI2). SPI1 promotes invasion of epithelial cells, whereas SPI2 enables S. Typhimurium to survive and proliferate within specialized compartments inside host cells. In this study, we show that an S. Typhimurium polyamine mutant is defective for invasion, intracellular survival, killing of the nematode Caenorhabditis elegans and systemic infection of the mouse model of typhoid fever. Virulence of the mutant could be restored by genetic complementation, and invasion and intracellular survival could, as well, be complemented by the addition of exogenous putrescine and spermidine to the bacterial cultures prior to infection. Interestingly, intracellular survival of the polyamine mutant was significantly enhanced above the wild type level by the addition of exogenous putrescine and spermidine to the bacterial cultures prior to infection, indicating that these polyamines function as an environmental signal that primes S. Typhimurium for intracellular survival. Accordingly, experiments addressed at elucidating the roles of these polyamines in infection revealed that expression of genes from both of the major virulence loci SPI1 and SPI2 responded to exogenous polyamines and was reduced in the polyamine mutant. Together our data demonstrate that putrescine and spermidine play a critical role in controlling virulence in S. Typhimurium most likely through stimulation of expression of essential virulence loci. Moreover, our data implicate these polyamines as key signals in S. Typhimurium virulence. PMID:22558361

  8. Legionella pneumophilaRequires Polyamines for Optimal Intracellular Growth ▿

    PubMed Central

    Nasrallah, Gheyath K.; Riveroll, Angela L.; Chong, Audrey; Murray, Lois E.; Lewis, P. Jeffrey; Garduño, Rafael A.

    2011-01-01

    The Gram-negative intracellular pathogen Legionella pneumophilareplicates in a membrane-bound compartment known as the Legionella-containing vacuole (LCV), into which it abundantly releases its chaperonin, HtpB. To determine whether HtpB remains within the LCV or reaches the host cell cytoplasm, we infected U937 human macrophages and CHO cells with L. pneumophilaexpressing a translocation reporter consisting of the Bordetella pertussisadenylate cyclase fused to HtpB. These infections led to increased cyclic AMP levels, suggesting that HtpB reaches the host cell cytoplasm. To identify potential functions of cytoplasmic HtpB, we expressed it in the yeast Saccharomyces cerevisiae, where HtpB induced pseudohyphal growth. A yeast-two-hybrid screen showed that HtpB interacted with S-adenosylmethionine decarboxylase (SAMDC), an essential yeast enzyme (encoded by SPE2) that is required for polyamine biosynthesis. Increasing the copy number of SPE2induced pseudohyphal growth in S. cerevisiae; thus, we speculated that (i) HtpB induces pseudohyphal growth by activating polyamine synthesis and (ii) L. pneumophilamay require exogenous polyamines for growth. A pharmacological inhibitor of SAMDC significantly reduced L. pneumophilareplication in L929 mouse cells and U937 macrophages, whereas exogenously added polyamines moderately favored intracellular growth, confirming that polyamines and host SAMDC activity promote L. pneumophilaproliferation. Bioinformatic analysis revealed that most known enzymes required for polyamine biosynthesis in bacteria (including SAMDC) are absent in L. pneumophila, further suggesting a need for exogenous polyamines. We hypothesize that HtpB may function to ensure a supply of polyamines in host cells, which are required for the optimal intracellular growth of L. pneumophila. PMID:21742865

  9. Structural basis of antizyme-mediated regulation of polyamine homeostasis

    PubMed Central

    Wu, Hsiang-Yi; Chen, Shin-Fu; Hsieh, Ju-Yi; Chou, Fang; Wang, Yu-Hsuan; Lin, Wan-Ting; Lee, Pei-Ying; Yu, Yu-Jen; Lin, Li-Ying; Lin, Te-Sheng; Lin, Chieh-Liang; Liu, Guang-Yaw; Tzeng, Shiou-Ru; Hung, Hui-Chih; Chan, Nei-Li

    2015-01-01

    Polyamines are organic polycations essential for cell growth and differentiation; their aberrant accumulation is often associated with diseases, including many types of cancer. To maintain polyamine homeostasis, the catalytic activity and protein abundance of ornithine decarboxylase (ODC), the committed enzyme for polyamine biosynthesis, are reciprocally controlled by the regulatory proteins antizyme isoform 1 (Az1) and antizyme inhibitor (AzIN). Az1 suppresses polyamine production by inhibiting the assembly of the functional ODC homodimer and, most uniquely, by targeting ODC for ubiquitin-independent proteolytic destruction by the 26S proteasome. In contrast, AzIN positively regulates polyamine levels by competing with ODC for Az1 binding. The structural basis of the Az1-mediated regulation of polyamine homeostasis has remained elusive. Here we report crystal structures of human Az1 complexed with either ODC or AzIN. Structural analysis revealed that Az1 sterically blocks ODC homodimerization. Moreover, Az1 binding triggers ODC degradation by inducing the exposure of a cryptic proteasome-interacting surface of ODC, which illustrates how a substrate protein may be primed upon association with Az1 for ubiquitin-independent proteasome recognition. Dynamic and functional analyses further indicated that the Az1-induced binding and degradation of ODC by proteasome can be decoupled, with the intrinsically disordered C-terminal tail fragment of ODC being required only for degradation but not binding. Finally, the AzIN–Az1 structure suggests how AzIN may effectively compete with ODC for Az1 to restore polyamine production. Taken together, our findings offer structural insights into the Az-mediated regulation of polyamine homeostasis and proteasomal degradation. PMID:26305948

  10. Biological treatment of highly contaminated acid mine drainage in batch reactors: Long-term treatment and reactive mixture characterization.

    PubMed

    Neculita, Carmen M; Zagury, Gérald J

    2008-09-15

    Passive bioreactors involving sulphate-reducing bacteria (SRB) are a practical alternative technology to treat acid mine drainage (AMD). Careful selection of the organic carbon source is important to ensure performance and long-term efficiency of the treatment. However, a rigorous and methodical characterization to predict the biodegradability of organic substrates by SRB still needs to be investigated. In the present study, four natural organic materials were thoroughly characterized to assess their ability to serve as substrates and to find a parameter that links organic carbon sources with their biodegradability. Three reactive mixtures were then comparatively evaluated for their performance to treat a highly contaminated AMD in long-term (152 days) batch experiments. All three mixtures were successful for sulphate reduction and metal (Fe, Ni, Cd, Zn, and Mn) removal (91.8-99.8%). Higher efficiencies were observed in the reactors with 30% (w/w) cellulosic wastes (maple wood chips and sawdust) which decreased sulphate concentrations from 5500 mg/L to <1mg/L, than in reactors with 2-3% cellulosic wastes, where final sulphate concentrations were in the range 2000-2750 mg/L. Organic material characterization indicated that higher C/N ratios, chemical oxygen demand (COD)/SO(4)(2-) ratios and dissolved organic carbon (DOC)/SO(4)(2-) ratios were associated with better sulphate-reducing conditions and metal removal. This work suggests that C/N and DOC/SO(4)(2-) ratios considered together are key parameters to assess the biodegradability of natural organic wastes under sulphate-reducing conditions.

  11. Alterations in polyamine levels induced by phorbol diesters and other agents that promote differentiation in human promyelocytic leukemia cells

    SciTech Connect

    Huberman, E.; Weeks, C.; Herrmann, A.; Callaham, M.; Slaga, T.

    1981-02-01

    Polyamine levels were evaluated in human HL-60 promyelocytic leukemia cells after treatment with inducers of terminal differentiation. Differentiation in these cells was determined by increases in the percentage of morphologically mature cells and in lysozyme activity. Treatment of the HL-60 cells with phorbol 12-myristate-13-acetate (PMA), phorbol 12,13-didecanoate or other inducers of terminal differentiation such as dimethylsulfoxide and retinoic acid resulted in increased levels of putrescine. However, no increase in putrescine could be detected after PMA treatment of a HL-60 cell variant that exhibited a decreased susceptibility to PMA-induced terminal differentiation. Similarly, no increase in putrescine was observed with two nontumor-promoters (phorbol 12,13-diacetate and 4-O-methyl-PMA) or with anthralin, a non-phorbol tumor promoter. In addition to enhancing putrescine levels, PMA also increased the amount of spermidine and decreased the amount of spermine. The increase in putrescine and spermidine preceded the expression of the various differentiation markers. Unlike the changes observed in the polyamine levels after PMA treatment, the activities of ornithine and S-adenosylmethionine decarboxylases, which are polyamine biosynthetic enzymes, did not significantly change. ..cap alpha..-Methylornithine and ..cap alpha..-difluoromethylornithine and methylglyoxal bis(guanylhydrazone), which are inhibitors of the polyamine biosynthetic enzymes, did not affect differentiation in control or PMA-treated cells. Because of these observations, we suggest that the change in polyamine levels involve biochemical pathways other than the known biosynthetic ones. By-products of these pathways may perhaps be the controlling factors involved in the induction of terminal differentiation in the HL-60 and other cell types as well.

  12. 3D-Membrane Stacks on Supported Membranes Composed of Diatom Lipids Induced by Long-Chain Polyamines.

    PubMed

    Gräb, Oliver; Abacilar, Maryna; Daus, Fabian; Geyer, Armin; Steinem, Claudia

    2016-10-04

    Long-chain polyamines (LCPAs) are intimately involved in the biomineralization process of diatoms taking place in silica deposition vesicles being acidic compartments surrounded by a lipid bilayer. Here, we addressed the question whether and how LCPAs interact with lipid membranes composed of glycerophospholipids and glyceroglycolipids mimicking the membranes of diatoms and higher plants. Solid supported lipid bilayers and monolayers containing the three major components that are unique in diatoms and higher plants, i.e., monogalactosyldiacylglycerol (MGDG), digalactosyldiacylglycerol (DGDG), and sulfoquinovosyldiacylglycerol (SQDG), were prepared by spreading small unilamellar vesicles. The integrity of the membranes was investigated by fluorescence microscopy and atomic force microscopy showing continuous flat bilayers and monolayers with small protrusions on top of the membrane. The addition of a synthetic polyamine composed of 13 amine groups separated by a propyl spacer (C3N13) results in flat but three-dimensional membrane stacks within minutes. The membrane stacks are connected with the underlying membrane as verified by fluorescence recovery after photobleaching experiments. Membrane stack formation was found to be independent of the lipid composition; i.e., neither glyceroglycolipids nor negatively charged lipids were required. However, the formation process was strongly dependent on the chain length of the polyamine. Whereas short polyamines such as the naturally occurring spermidine, spermine, and the synthetic polyamines C3N4 and C3N5 do not induce stack formation, those containing seven and more amine groups (C3N7, C3N13, and C3N18) do form membrane stacks. The observed stack formation might have implications for the stability and expansion of the silica deposition vesicle during valve and girdle band formation in diatoms.

  13. Thermodynamic origin of the solubility profile of drugs showing one or two maxima against the polarity of aqueous and nonaqueous mixtures: niflumic acid and caffeine.

    PubMed

    Bustamante, Pilar; Navarro, J; Romero, S; Escalera, B

    2002-03-01

    The purpose of this work was to investigate the origin of the different solubility profiles of drugs against the polarity of solvent mixtures with a common cosolvent. Niflumic acid and caffeine where chosen as model drugs. The solubilities were measured at five or six temperatures in aqueous (ethanol-water) and nonaqueous (ethyl acetate-ethanol) mixtures. The enthalpies of solution were obtained at the harmonic mean of the experimental temperature. Solid phase changes were analyzed using differential scanning calorimetry and thermomicroscopy. A single solubility maximum was obtained for niflumic acid against the solubility parameter of both mixtures that is not related to solid phase changes. In contrast, caffeine displays two maxima and anhydrous-hydrate transition occurs at the solubility peak in the amphiprotic mixture. The apparent enthalpies of solution of both drugs show endothermic maxima against solvent composition that are related to hydrophobic hydration. A general explanation for the cosolvent action in aqueous mixtures is proposed. The dominant mechanism shifts from entropy to enthalpy at a certain cosolvent ratio dependent on the hydrophobicity and the solubility parameter of the drug. Niflumic acid and caffeine show enthalpy-entropy compensation in ethanol-water, and this relationship is demonstrated for the first time in nonaqueous mixtures. The results support that enthalpy-entropy compensation is a general effect for the solubility of drugs in solvent mixtures. The shape of the solubility curves is correlated with the compensation plots. The solubility peaks separate different enthalpy-entropy relationships that also differentiate the solubility behavior of the hydrate and the anhydrous forms of caffeine.

  14. Polyamine catabolism in carcinogenesis: potential targets for chemotherapy and chemoprevention.

    PubMed

    Battaglia, Valentina; DeStefano Shields, Christina; Murray-Stewart, Tracy; Casero, Robert A

    2014-03-01

    Polyamines, including spermine, spermidine, and the precursor diamine, putrescine, are naturally occurring polycationic alkylamines that are required for eukaryotic cell growth, differentiation, and survival. This absolute requirement for polyamines and the need to maintain intracellular levels within specific ranges require a highly regulated metabolic pathway primed for rapid changes in response to cellular growth signals, environmental changes, and stress. Although the polyamine metabolic pathway is strictly regulated in normal cells, dysregulation of polyamine metabolism is a frequent event in cancer. Recent studies suggest that the polyamine catabolic pathway may be involved in the etiology of some epithelial cancers. The catabolism of spermine to spermidine utilizes either the one-step enzymatic reaction of spermine oxidase (SMO) or the two-step process of spermidine/spermine N (1)-acetyltransferase (SSAT) coupled with the peroxisomal enzyme N (1)-acetylpolyamine oxidase. Both catabolic pathways produce hydrogen peroxide and a reactive aldehyde that are capable of damaging DNA and other critical cellular components. The catabolic pathway also depletes the intracellular concentrations of spermidine and spermine, which are free radical scavengers. Consequently, the polyamine catabolic pathway in general and specifically SMO and SSAT provide exciting new targets for chemoprevention and/or chemotherapy.

  15. Polyamine catabolism in carcinogenesis: potential targets for chemotherapy and chemoprevention

    PubMed Central

    Battaglia, Valentina; Shields, Christina DeStefano; Murray-Stewart, Tracy; Casero, Robert A.

    2013-01-01

    Polyamines, including spermine, spermidine, and the precursor diamine, putrescine, are naturally occurring polycationic alkylamines that are required for eukaryotic cell growth, differentiation, and survival. This absolute requirement for polyamines and the need to maintain intracellular levels within specific ranges requires a highly regulated metabolic pathway primed for rapid changes in response to cellular growth signals, environmental changes, and stress. Although the polyamine metabolic pathway is strictly regulated in normal cells, dysregulation of polyamine metabolism is a frequent event in cancer. Recent studies suggest that the polyamine catabolic pathway may be involved in the etiology of some epithelial cancers. The catabolism of spermine to spermidine utilizes either the one-step enzymatic reaction of spermine oxidase (SMO) or the two-step process of spermidine/spermine N1-acetyltransferase (SSAT) coupled with the peroxisomal enzyme N1-acetylpolyamine oxidase (APAO). Both catabolic pathways produce hydrogen peroxide (H2O2) and a reactive aldehyde that are capable of damaging DNA and other critical cellular components. The catabolic pathway also depletes the intracellular concentrations of spermidine and spermine, which are free radical scavengers. Consequently, the polyamine catabolic pathway in general and specifically SMO and SSAT provide exciting new targets for chemoprevention and/or chemotherapy. PMID:23771789

  16. Interaction of tRNA with antitumor polyamine analogues.

    PubMed

    N'soukpoé-Kossi, C N; Ahmed Ouameur, A; Thomas, T; Thomas, T J; Tajmir-Riahi, H A

    2009-08-01

    We studied the interaction between tRNA and three polyamine analogues (1,11-diamino-4,8-diazaundecane.4HCl (333), 3,7,11,15-tetrazaheptadecane.4HCl (BE-333), and 3,7,11,15,19-pentazahenicosane.5HCl (BE-3333)) using FTIR, UV-visible, and CD spectroscopic methods. Spectroscopic evidence showed that polyamine analogues bound tRNA via guanine N7, adenine, uracil O2, and the backbone phosphate (PO2-) groups, while the most reactive sites for biogenic polyamines were guanine N7/O6, adenine N7, uracil O2, and sugar 2'-OH groups as well as the backbone phosphate group. The binding constants of polyamine analogue-tRNA recognition were lower than those of the biogenic polyamine-tRNA complexes, with K333 = 2.8 (+/-0.5) x 10(4), K(BE-333) = 3.7 (+/-0.7) x 10(4), K(BE-3333) = 4.0 (+/-0.9) x 10(4), K(spm) = 8.7 (+/-0.9) x 10(5), K(spd) = 6.1 (+/-0.7) x 10(5), and K(put) = 1.0 (+/-0.3) x 10(5) mol/L. tRNA remained in the A-family conformation; however, it aggregated at high polyamine analogue concentrations.

  17. Extensive reduction of cell viability and enhanced matrix production in Pseudomonas aeruginosa PAO1 flow biofilms treated with a D-amino acid mixture.

    PubMed

    Sanchez, Zoe; Tani, Akio; Kimbara, Kazuhide

    2013-02-01

    Treatment of Pseudomonas aeruginosa PAO1 flow biofilms with a D-amino acid mixture caused significant reductions in cell biomass by 75% and cell viability by 71%. No biofilm disassembly occurred, and matrix production increased by 30%, thereby providing a thick protective cover for remaining viable or persister cells.

  18. Evaluation of additivity of binary mixtures of perfluoroalkyl acids (PFAAs) on peroxisome proliferator-activated receptor-alpha (PPARa) activation in vitro

    EPA Science Inventory

    Perfluoroalkyl acids (PFAAs) are found globally in the environment and in animal tissues, and are present as mixtures of PFAA congeners. Mechanistic studies have found that in vivo effects of PFAAs are mediated by PPARL. Our previous studies showed that individual PFAAs activate ...

  19. The effect of Centella asiatica, vitamins, glycolic acid and their mixtures preparations in stimulating collagen and fibronectin synthesis in cultured human skin fibroblast.

    PubMed

    Hashim, Puziah

    2014-03-01

    Centella asiatica (Linn.) Urban is well known in promoting wound healing and provides significant benefits in skin care and therapeutic products formulation. Glycolic acid and vitamins also play a role in the enhancement of collagen and fibronectin synthesis. Here, we evaluate the specific effect of Centella asiatica (CA), vitamins, glycolic acid and their mixture preparations to stimulate collagen and fibronectin synthesis in cultured human fibroblast cells. The fibroblast cells are incubated with CA, glycolic acid, vitamins and their mixture preparations for 48 h. The cell lysates were analyzed for protein content and collagen synthesis by direct binding enzyme immunoassay. The fibronectin of the cultured supernatant was measured by sandwich enzyme immunoassay. The results showed that CA, glycolic acid, vitamins A, E and C significantly stimulate collagen and fibronectin synthesis in the fibroblast. Addition of glycolic acid and vitamins to CA further increased the levels of collagen and fibronectin synthesis to 8.55 and 23.75 μg/100 μg, respectively. CA, glycolic acid, vitamins A, E, and C, and their mixtures demonstrated stimulatory effect on both extra-cellular matrix synthesis of collagen and fibronectin in in vitro studies on human foreskin fibroblasts, which is beneficial to skin care and therapeutic products formulation.

  20. Bacterial flora of processed broiler chicken skin after successive washings in mixtures of potassium hydroxide and lauric acid.

    PubMed

    Hinton, Arthur; Cason, John A

    2008-08-01

    Changes in the size of populations of different groups of bacteria composing the normal flora of processed broiler skin were examined after each of five consecutive washings in mixtures of potassium hydroxide (KOH) and lauric acid (LA). Portions of skin from commercially processed broiler carcasses were washed in distilled water (control) or in mixtures of 0.25% KOH-0.5% LA or 0.5% KOH-1% LA by using a stomacher laboratory blender to agitate the skin in the solutions. After each wash, skin was transferred to fresh solutions, and washing was repeated to provide samples washed one to five times in each solution. Bacteria in rinsates of the washed skin were enumerated on plate count (PC) agar, Staphylococcus (STA) agar, Levine eosin methylene blue (EMB) agar, lactic acid bacteria (LAB) agar, and Perfringens (PER) agar with TSC supplement. Selected isolates recovered on each medium were identified. Overall, no significant differences were observed in numbers of bacteria recovered on PC, STA, or EMB agars from skin after repeated washing in water, but there were significant reductions in the number of bacteria recovered on LAB and PER agars. Repeated washing of skin in 0.25% KOH-0.5% LA or 0.5% KOH-1% LA generally produced significant reductions in the number of bacteria recovered on all media. Furthermore, no bacteria were recovered on PER agar from skin washed five times in 0.25% KOH-0.5% LA. Likewise, no bacteria were recovered on EMB or LAB agars from skin washed three or more times in 0.5% KOH-1% LA or on PER agar from skin washed four or five times in this solution. Staphylococcus spp. were identified as the skin isolates with the highest degree of resistance to the bactericidal activity of KOH-LA. Findings indicate that although bacteria may be continually shed from poultry skin after repeated washings, bactericidal surfactants can be used to remove and kill several types of bacteria found on the surface of the skin of processed broilers.

  1. Pharmacological potential of biogenic amine–polyamine interactions beyond neurotransmission

    PubMed Central

    Sánchez-Jiménez, F; Ruiz-Pérez, M V; Urdiales, J L; Medina, M A

    2013-01-01

    Histamine, serotonin and dopamine are biogenic amines involved in intercellular communication with multiple effects on human pathophysiology. They are products of two highly homologous enzymes, histidine decarboxylase and l-aromatic amino acid decarboxylase, and transmit their signals through different receptors and signal transduction mechanisms. Polyamines derived from ornithine (putrescine, spermidine and spermine) are mainly involved in intracellular effects related to cell proliferation and death mechanisms. This review summarizes structural and functional evidence for interactions between components of all these amine metabolic and signalling networks (decarboxylases, transporters, oxidases, receptors etc.) at cellular and tissue levels, distinct from nervous and neuroendocrine systems, where the crosstalk among these amine-related components can also have important pathophysiological consequences. The discussion highlights aspects that could help to predict and discuss the effects of intervention strategies. Linked Articles This article is part of a themed issue on Histamine Pharmacology Update. To view the other articles in this issue visit http://dx.doi.org/10.1111/bph.2013.170.issue-1 PMID:23347064

  2. The electroplated Pd-Co alloy film on 316 L stainless steel and the corrosion resistance in boiling acetic acid and formic acid mixture with stirring

    NASA Astrophysics Data System (ADS)

    Li, Sirui; Zuo, Yu; Tang, Yuming; Zhao, Xuhui

    2014-12-01

    Pd-Co alloy films were deposited on 316 L stainless steel by electroplating. Scanning electronic microscopy, X-ray photoelectron spectroscopy, X-ray diffraction, weight loss test and polarization test were used to determine the properties of the Pd-Co alloy films. The Pd-Co films show fine grain size, low porosity and obviously high micro-hardness. The Co content in the film can be controlled in a large range from 21.9 at.% to 57.42 at.%. Pd is rich on the Pd-Co film surface, which is benefit to increase the corrosion resistance. In boiling 90% acetic acid plus 10% formic acid mixture with 0.005 M Br- under stirring, the Pd-Co plated stainless steel samples exhibit evidently better corrosion resistance in contrast to Pd plated samples. The good corrosion resistance of the Pd-Co alloy film is explained by the better compactness, the lower porosity, and the obviously higher micro-hardness of the alloy films, which increases the resistance to erosion and retards the development of micro-pores in the film.

  3. Studies of single aerosol particles containing malonic acid, glutaric acid, and their mixtures with sodium chloride. II. Liquid-state vapor pressures of the acids.

    PubMed

    Pope, Francis D; Tong, Hai-Jie; Dennis-Smither, Ben J; Griffiths, Paul T; Clegg, Simon L; Reid, Jonathan P; Cox, R Anthony

    2010-09-23

    The vapor pressures of two dicarboxylic acids, malonic acid and glutaric acid, are determined by the measurement of the evaporation rate of the dicarboxylic acids from single levitated particles. Two laboratory methods were used to isolate single particles, an electrodynamic balance and optical tweezers (glutaric acid only). The declining sizes of individual aerosol particles over time were followed using elastic Mie scattering or cavity enhanced Raman scattering. Experiments were conducted over the temperature range of 280-304 K and a range of relative humidities. The subcooled liquid vapor pressures of malonic and glutaric acid at 298.15 K were found to be 6.7(-1.2)(+2.6) x 10(-4) and 11.2(-4.7)(+9.6) x 10(-4) Pa, respectively, and the standard enthalpies of vaporization were respectively 141.9 ± 19.9 and 100.8 ± 23.9 kJ mol(-1). The vapor pressures of both glutaric acid and malonic acid in single particles composed of mixed inorganic/organic composition were found to be independent of salt concentration within the uncertainty of the measurements. Results are compared with previous laboratory determinations and theoretical predictions.

  4. Nanoparticle self-assembly in mixtures of phospholipids with styrene/maleic acid copolymers or fluorinated surfactants

    NASA Astrophysics Data System (ADS)

    Vargas, Carolyn; Arenas, Rodrigo Cuevas; Frotscher, Erik; Keller, Sandro

    2015-12-01

    Self-assembling nanostructures in aqueous mixtures of bilayer-forming lipids and micelle-forming surfactants are relevant to in vitro studies on biological and synthetic membranes and membrane proteins. Considerable efforts are currently underway to replace conventional detergents by milder alternatives such as styrene/maleic acid (SMA) copolymers and fluorinated surfactants. However, these compounds and their nanosized assemblies remain poorly understood as regards their interactions with lipid membranes, particularly, the thermodynamics of membrane partitioning and solubilisation. Using 19F and 31P nuclear magnetic resonance spectroscopy, static and dynamic light scattering, and isothermal titration calorimetry, we have systematically investigated the aggregational state of a zwitterionic bilayer-forming phospholipid upon exposure to an SMA polymer with a styrene/maleic acid ratio of 3 : 1 or to a fluorinated octyl phosphocholine derivative called F6OPC. The lipid interactions of SMA(3 : 1) and F6OPC can be thermodynamically conceptualised within the framework of a three-stage model that treats bilayer vesicles, discoidal or micellar nanostructures, and the aqueous solution as distinct pseudophases. The exceptional solubilising power of SMA(3 : 1) is reflected in very low membrane-saturating and solubilising polymer/lipid molar ratios of 0.10 and 0.15, respectively. Although F6OPC saturates bilayers at an even lower molar ratio of 0.031, this nondetergent does not solubilise lipids even at >1000-fold molar excess, thus highlighting fundamental differences between these two types of mild membrane-mimetic systems. We rationalise these findings in terms of a new classification of surfactants based on bilayer-to-micelle transfer free energies and discuss practical implications for membrane-protein research.Self-assembling nanostructures in aqueous mixtures of bilayer-forming lipids and micelle-forming surfactants are relevant to in vitro studies on biological and

  5. Critical-point universality in adsorption: The effect of charcoal on a mixture of isobutyric acid and water near the consolute point

    NASA Astrophysics Data System (ADS)

    Giesy, Timothy J.; Chou, Alan S.; McFeeters, Robert L.; Baird, James K.; Barlow, Douglas A.

    2011-06-01

    The mixture of isobutyric acid and water has a consolute point at a temperature of 25.75 °C and mole fraction 0.1148 isobutyric acid. When charcoal is added to this mixture, the concentration of isobutyric acid is reduced by adsorption. We have measured the action of charcoal on solutions of isobutyric acid and water as a function of isobutyric acid mole fraction at temperatures of 25.85 and 32.50 °C. At the higher temperature, the specific adsorption density (y2α/m) satisfies the Freundlich equation (y2α/m)=KX21/n, where y2α is the mass of isobutyric acid adsorbed, m is the mass of charcoal, X2 is the equilibrium mole fraction of isobutyric acid, n is the Freundlich index, and K=K(T) is an amplitude that depends upon the temperature T. At 25.85 °C, a critical endpoint is located at an isobutyric acid mole fraction X2ce=0.09. When compared with the Freundlich equation at this temperature, a plot of the specific adsorption density as a function of X2 in the vicinity of the critical-endpoint composition assumes a shape which is reminiscent of the derivative of a Dirac delta function. Using critical-point scaling theory, we show that this divergent pattern is consistent with the principle of critical point universality.

  6. Critical-point universality in adsorption: the effect of charcoal on a mixture of isobutyric acid and water near the consolute point.

    PubMed

    Giesy, Timothy J; Chou, Alan S; McFeeters, Robert L; Baird, James K; Barlow, Douglas A

    2011-06-01

    The mixture of isobutyric acid and water has a consolute point at a temperature of 25.75 °C and mole fraction 0.1148 isobutyric acid. When charcoal is added to this mixture, the concentration of isobutyric acid is reduced by adsorption. We have measured the action of charcoal on solutions of isobutyric acid and water as a function of isobutyric acid mole fraction at temperatures of 25.85 and 32.50 °C. At the higher temperature, the specific adsorption density (y(2)(α)/m) satisfies the Freundlich equation (y(2)(α)/m)=KX(2)(1/n), where y(2)(α) is the mass of isobutyric acid adsorbed, m is the mass of charcoal, X(2) is the equilibrium mole fraction of isobutyric acid, n is the Freundlich index, and K=K(T) is an amplitude that depends upon the temperature T. At 25.85 °C, a critical endpoint is located at an isobutyric acid mole fraction X(2)(ce)=0.09. When compared with the Freundlich equation at this temperature, a plot of the specific adsorption density as a function of X(2) in the vicinity of the critical-endpoint composition assumes a shape which is reminiscent of the derivative of a Dirac delta function. Using critical-point scaling theory, we show that this divergent pattern is consistent with the principle of critical point universality.

  7. Pharmacopeial compliance of fish oil-containing parenteral lipid emulsion mixtures: Globule size distribution (GSD) and fatty acid analyses.

    PubMed

    Driscoll, David F; Ling, Pei-Ra; Bistrian, Bruce R

    2009-09-08

    Recently, the United States Pharmacopeia (USP) has established Chapter 729 with GSD limits for all lipid emulsions where the mean droplet size (MDS) must be <500 nm and the percent of fat larger than 5 microm (PFAT(5)) must be <0.05%, irrespective of the final lipid concentration. As well, the European Pharmacopeia (EP) Monograph no. 1352 specifies n3-fatty acid (FA) limits (EPA+DHA> or =45%; total n3 or T-n3> or =60%) for fish oil. We assessed compliance with USP physical and EP chemical limits of two fish oil-containing lipid emulsion mixtures. All lipid emulsions passed USP 729 limits. No samples tested had an MDS >302 nm or a PFAT(5) value >0.011%. Only one product met EP limits while the other failed. All emulsions tested were extremely fine dispersions and easily met USP 729 GSD limits. The n3-FAs profiles were lower in one, despite being labeled to contain 50% more fish oil than the other product. This latter finding suggests the n3-FA content of the fish oil source and/or the applied manufacturing processes in these products is different.

  8. A Mixture of Persistent Organic Pollutants and Perfluorooctanesulfonic Acid Induces Similar Behavioural Responses, but Different Gene Expression Profiles in Zebrafish Larvae

    PubMed Central

    Khezri, Abdolrahman; Fraser, Thomas W. K.; Nourizadeh-Lillabadi, Rasoul; Kamstra, Jorke H.; Berg, Vidar; Zimmer, Karin E.; Ropstad, Erik

    2017-01-01

    Persistent organic pollutants (POPs) are widespread in the environment and some may be neurotoxic. As we are exposed to complex mixtures of POPs, we aimed to investigate how a POP mixture based on Scandinavian human blood data affects behaviour and neurodevelopment during early life in zebrafish. Embryos/larvae were exposed to a series of sub-lethal doses and behaviour was examined at 96 h post fertilization (hpf). In order to determine the sensitivity window to the POP mixture, exposure models of 6 to 48 and 48 to 96 hpf were used. The expression of genes related to neurological development was also assessed. Results indicate that the POP mixture increases the swimming speed of larval zebrafish following exposure between 48 to 96 hpf. This behavioural effect was associated with the perfluorinated compounds, and more specifically with perfluorooctanesulfonic acid (PFOS). The expression of genes related to the stress response, GABAergic, dopaminergic, histaminergic, serotoninergic, cholinergic systems and neuronal maintenance, were altered. However, there was little overlap in those genes that were significantly altered by the POP mixture and PFOS. Our findings show that the POP mixture and PFOS can have a similar effect on behaviour, yet alter the expression of genes relevant to neurological development differently. PMID:28146072

  9. Hypolipidemic and hepatoprotective effects of flax and pumpkin seed mixture rich in omega-3 and omega-6 fatty acids in hypercholesterolemic rats.

    PubMed

    Makni, M; Fetoui, H; Gargouri, N K; Garoui, El M; Jaber, H; Makni, J; Boudawara, T; Zeghal, N

    2008-12-01

    Flax and pumpkin seeds are a rich source of unsaturated fatty acids, antioxidants and fibers, known to have anti-atherogenic and hepatoprotective activities. These effects were evaluated in Wistar rats fed with 1% cholesterol diet. The study was performed on 30 male rats divided into three groups: a control group (CD), CD-chol group fed diet with 1% cholesterol and MS-chol group fed diet enriched with flax and pumpkin seed mixture. In CD-chol group, total cholesterol TC, triacylglycerol TG in plasma and liver, plasma LDL-C, atherogenic index AI and LDL/HDL ratio significantly increased. In MS-chol group lipid parameters decreased significantly, plasma and liver fatty acid composition showed an increase of PUFAs (ALA and LA), and MUFAs (oleic and eicosaenoic acid) and a decrease of SFA (palmitic and stearic acid). In plasma and liver of MS-chol group, malondialdehyde levels decreased and the efficiency of antioxidant defense system was improved compared to CD-chol group. Liver histological sections showed lipid storage in hepatocytes of CD-chol group and an improvement was noted in MS-chol group. Our results suggested that flax and pumpkin seed mixture had anti-atherogenic and hepatoprotective effects which were probably mediated by unsaturated fatty acids present in seed mixture.

  10. Genome Wide Association Mapping for the Tolerance to the Polyamine Oxidase Inhibitor Guazatine in Arabidopsis thaliana

    PubMed Central

    Atanasov, Kostadin E.; Barboza-Barquero, Luis; Tiburcio, Antonio F.; Alcázar, Rubén

    2016-01-01

    Guazatine is a potent inhibitor of polyamine oxidase (PAO) activity. In agriculture, guazatine is used as non-systemic contact fungicide efficient in the protection of cereals and citrus fruits against disease. The composition of guazatine is complex, mainly constituted by a mixture of synthetic guanidated polyamines (polyaminoguanidines). Here, we have studied the effects from exposure to guazatine in the weed Arabidopsis thaliana. We report that micromolar concentrations of guazatine are sufficient to inhibit growth of Arabidopsis seedlings and induce chlorosis, whereas germination is barely affected. We observed the occurrence of quantitative variation in the response to guazatine between 107 randomly chosen Arabidopsis accessions. This enabled us to undertake genome-wide association (GWA) mapping that identified a locus on chromosome one associated with guazatine tolerance. CHLOROPHYLLASE 1 (CLH1) within this locus was studied as candidate gene, together with its paralog (CLH2). The analysis of independent clh1-2, clh1-3, clh2-3, clh2-2, and double clh1-2 clh2-3 mutant alleles indicated that CLH1 and/or CLH2 loss-of-function or expression down-regulation promote guazatine tolerance in Arabidopsis. We report a natural mechanism by which Arabidopsis populations can overcome toxicity by the fungicide guazatine. PMID:27092150

  11. Genome Wide Association Mapping for the Tolerance to the Polyamine Oxidase Inhibitor Guazatine in Arabidopsis thaliana.

    PubMed

    Atanasov, Kostadin E; Barboza-Barquero, Luis; Tiburcio, Antonio F; Alcázar, Rubén

    2016-01-01

    Guazatine is a potent inhibitor of polyamine oxidase (PAO) activity. In agriculture, guazatine is used as non-systemic contact fungicide efficient in the protection of cereals and citrus fruits against disease. The composition of guazatine is complex, mainly constituted by a mixture of synthetic guanidated polyamines (polyaminoguanidines). Here, we have studied the effects from exposure to guazatine in the weed Arabidopsis thaliana. We report that micromolar concentrations of guazatine are sufficient to inhibit growth of Arabidopsis seedlings and induce chlorosis, whereas germination is barely affected. We observed the occurrence of quantitative variation in the response to guazatine between 107 randomly chosen Arabidopsis accessions. This enabled us to undertake genome-wide association (GWA) mapping that identified a locus on chromosome one associated with guazatine tolerance. CHLOROPHYLLASE 1 (CLH1) within this locus was studied as candidate gene, together with its paralog (CLH2). The analysis of independent clh1-2, clh1-3, clh2-3, clh2-2, and double clh1-2 clh2-3 mutant alleles indicated that CLH1 and/or CLH2 loss-of-function or expression down-regulation promote guazatine tolerance in Arabidopsis. We report a natural mechanism by which Arabidopsis populations can overcome toxicity by the fungicide guazatine.

  12. Thermodynamic analysis of biogenic and synthetic polyamines conjugation with PAMAM-G4 nanoparticles.

    PubMed

    Chanphai, P; Tajmir-Riahi, H A

    2016-02-01

    We report the thermodynamic analysis of the bindings of poly(amidoamine) (PAMAM-G4) nanoparticles with biogenic polyamines spermine (spm), spermidine (spmd) and synthetic polyamines 3,7,11,15-tetrazaheptadecane·4HCl (BE-333) in aqueous solution at physiological conditions. Multiple spectroscopic methods, thermodynamic parameters and molecular modelling were used to analyse polyamine bindings to PAMAM dendrimers. Thermodynamic parameters ΔS, ΔH and ΔG parameters showed that polyamines bind polymer through H-bonding and van der Waals contacts with biogenic polyamines form more stable conjugates than synthetic polyamines. Modelling showed that polyamines are located at the surface of PAMAM with the free binding energy of -3.56 (spermine), -3.88 (spermidine) and -3.13 kcal/mol (BE-333), indicating spontaneous polyamine-polymer interaction at room temperature.

  13. Naturally occurring branched-chain polyamines induce a crosslinked meshwork structure in a giant DNA

    NASA Astrophysics Data System (ADS)

    Muramatsu, Akira; Shimizu, Yuta; Yoshikawa, Yuko; Fukuda, Wakao; Umezawa, Naoki; Horai, Yuhei; Higuchi, Tsunehiko; Fujiwara, Shinsuke; Imanaka, Tadayuki; Yoshikawa, Kenichi

    2016-12-01

    We studied the effect of branched-chain polyamines on the folding transition of genome-sized DNA molecules in aqueous solution by the use of single-molecule observation with fluorescence microcopy. Detailed morphological features of polyamine/DNA complexes were characterized by atomic force microscopy (AFM). The AFM observations indicated that branched-chain polyamines tend to induce a characteristic change in the higher-order structure of DNA by forming bridges or crosslinks between the segments of a DNA molecule. In contrast, natural linear-chain polyamines cause a parallel alignment between DNA segments. Circular dichroism measurements revealed that branched-chain polyamines induce the A-form in the secondary structure of DNA, while linear-chain polyamines have only a minimum effect. This large difference in the effects of branched- and linear-chain polyamines is discussed in relation to the difference in the manner of binding of these polyamines to negatively charged double-stranded DNA.

  14. Effect of dietary putrescine on whole body growth and polyamine metabolism.

    PubMed

    Smith, T K

    1990-09-01

    Putrescine (1,4-diaminobutane) is the simplest of the mammalian polyamines. These are small, positively charged molecules which are essential for cell growth and are thought to play a role in regulation of anabolic events such as synthesis of DNA, RNA, and protein. Recent reports have indicated the potential for dietary precursor amino acids of putrescine to alter tissue putrescine concentrations. The current study was conducted to determine the physiologic significance of these effects by feeding up to flooding doses of putrescine to determine any influence on whole body growth and polyamine metabolism. A total of 96 chicks were fed purified crystalline amino acid diets containing 0.0, 0.2, 0.4, 0.6, 0.8, or 1.0% purified putrescine (four birds per pen, four pens per diet) for 14 days. The feeding of 0.2% putrescine increased growth rate beyond that of controls while further supplements reduced growth and were toxic when 0.8 and 1.0% putrescine were fed. Hepatic and muscle concentrations of ornithine increased with dietary putrescine while the effect in kidney was much less. Putrescine concentrations in liver, kidney, and muscle rose when 0.4% putrescine or more was fed. This effect was particularly obvious in muscle in which there were also increases in the concentrations of spermidine and spermine. In a subsequent similar experiment, putrescine was fed at 0.0, 0.1, 0.2, 0.3, 0.4, or 0.5% to determine the effect on the activities of the key enzymes regulating polyamine synthesis. The feeding of putrescine at even 0.1% caused a rapid reduction in hepatic ornithine decarboxylase activity while S-adenosylmethionine decarboxylase and arginase activities were not influenced by diet. It was concluded that excess tissue putrescine can be toxic to whole organisms but small, orally administered doses of this metabolite can promote growth.

  15. Dietary arginine affects energy metabolism through polyamine turnover in juvenile Atlantic salmon (Salmo salar).

    PubMed

    Andersen, Synne M; Holen, Elisabeth; Aksnes, Anders; Rønnestad, Ivar; Zerrahn, Jens-Erik; Espe, Marit

    2013-12-14

    In the present study, quadruplicate groups of juvenile Atlantic salmon (Salmo salar) were fed plant protein-based diets with increasing arginine inclusions (range 28·8-37·4 g/kg DM) to investigate whether arginine supplementation affects growth and lipid accumulation through an elevated polyamine turnover. Dietary lysine was held at a constant concentration, just below the requirement. All other amino acids were balanced and equal in the diets. Arginine supplementation increased protein and fat accretion, without affecting the hepatosomatic or visceralsomatic indices. Dietary arginine correlated with putrescine in the liver (R 0·78, P= 0·01) and with ornithine in the muscle, liver and plasma (P= 0·0002, 0·003 and 0·0002, respectively). The mRNA of ornithine decarboxylase, the enzyme producing putrescine, was up-regulated in the white adipose tissue of fish fed the high-arginine inclusion compared with those fed the low-arginine diet. Concomitantly, spermidine/spermine-(N1)-acetyltransferase, the rate-limiting enzyme for polyamine turnover that consumes acetyl-CoA, showed an increased activity in the liver of fish fed the arginine-supplemented diets. In addition, lower acetyl-CoA concentrations were observed in the liver of fish fed the high-arginine diet, while ATP, which is used in the process of synthesising spermidine and spermine, did not show a similar trend. Gene expression of the rate-limiting enzyme for β-oxidation of long-chain fatty acids, carnitine palmitoyl transferase-1, was up-regulated in the liver of fish fed the high-arginine diet. Taken together, the data support that increased dietary arginine activates polyamine turnover and β-oxidation in the liver of juvenile Atlantic salmon and may act to improve the metabolic status of the fish.

  16. Milk Yield, Composition, and Fatty Acid Profile in Dairy Cows Fed a High-concentrate Diet Blended with Oil Mixtures Rich in Polyunsaturated Fatty Acids

    PubMed Central

    Thanh, Lam Phuoc; Suksombat, Wisitiporn

    2015-01-01

    To evaluate the effects of feeding linseed oil or/and sunflower oil mixed with fish oil on milk yield, milk composition and fatty acid (FA) profiles of dairy cows fed a high-concentrate diet, 24 crossbred primiparous lactating dairy cows in early lactation were assigned to a completely randomized design experiment. All cows were fed a high-concentrate basal diet and 0.38 kg dry matter (DM) molasses per day. Treatments were composed of a basal diet without oil supplement (Control), or diets of (DM basis) 3% linseed and fish oils (1:1, w/w, LSO-FO), or 3% sunflower and fish oils (1:1, w/w, SFO-FO), or 3% mixture (1:1:1, w/w) of linseed, sunflower, and fish oils (MIX-O). The animals fed SFO-FO had a 13.12% decrease in total dry matter intake compared with the control diet (p<0.05). No significant change was detected for milk yield; however, the animals fed the diet supplemented with SFO-FO showed a depressed milk fat yield and concentration by 35.42% and 27.20%, respectively, compared to those fed the control diet (p<0.05). Milk c9, t11-conjugated linoleic acid (CLA) proportion increased by 198.11% in the LSO-FO group relative to the control group (p<0.01). Milk C18:3n-3 (ALA) proportion was enhanced by 227.27% supplementing with LSO-FO relative to the control group (p<0.01). The proportions of milk docosahexaenoic acid (DHA) were significantly increased (p<0.01) in the cows fed LSO-FO (0.38%) and MIX-O (0.23%) compared to the control group (0.01%). Dietary inclusion of LSO-FO mainly increased milk c9, t11-CLA, ALA, DHA, and n-3 polyunsaturated fatty acids (PUFA), whereas feeding MIX-O improved preformed FA and unsaturated fatty acids (UFA). While the lowest n-6/n-3 ratio was found in the LSO-FO, the decreased atherogenecity index (AI) and thrombogenicity index (TI) seemed to be more extent in the MIX-O. Therefore, to maximize milk c9, t11-CLA, ALA, DHA, and n-3 PUFA and to minimize milk n-6/n-3 ratio, AI and TI, an ideal supplement would appear to be either LSO-FO or

  17. Structural identification of long-chain polyamines associated with diatom biosilica in a Southern Ocean sediment core

    NASA Astrophysics Data System (ADS)

    Bridoux, Maxime C.; Ingalls, Anitra E.

    2010-07-01

    Long-chain polyamines (LCPAs) constitute a new family of natural organic compounds that have recently been isolated and characterized from the biosilicified cell walls of diatom cultures. To date, diatom-specific polyamines have not been investigated from the marine environment and their fate in the environment is entirely unknown. Here, we report a series of LCPAs in a diatom frustule-rich sediment core (TNO57-13 PC4), originating from the Atlantic sector of the Southern Ocean and spanning from the Holocene to the Last Glacial Maximum (LGM). Liquid chromatography with electrospray ionization mass spectrometry (LC-ESI-MS) revealed a complex mixture of linear polyamines with at least 28 individual molecular species. Ion trap mass fragmentation studies, combined with high resolution Time of Flight (TOF) mass spectrometry showed that the polyamine pool consisted of a series of N-methylated propylamine compounds attached to a putrescine moiety, with individual LCPAs varying in chain length and degree of methylation. The structural similarity between LCPAs extracted from the diatom-rich sediment core and those extracted from the frustules of cultured diatoms suggests that sedimentary LCPAs are derived from diatom frustules. We hypothesize that these intrinsically labile organic molecular fossils are protected from diagenesis by encapsulation within the frustule. These compounds constitute a new class of biomarkers that could potentially be indicators of diatom species distribution. Isotopic analysis of LCPAs could be used to improve age models for sediment cores that lack calcium carbonate and to improve current interpretations of diatom-based paleoproxies, including diatom-bound nitrogen isotopes.

  18. Polyamines and abiotic stress in plants: a complex relationship1

    PubMed Central

    Minocha, Rakesh; Majumdar, Rajtilak; Minocha, Subhash C.

    2014-01-01

    The physiological relationship between abiotic stress in plants and polyamines was reported more than 40 years ago. Ever since there has been a debate as to whether increased polyamines protect plants against abiotic stress (e.g., due to their ability to deal with oxidative radicals) or cause damage to them (perhaps due to hydrogen peroxide produced by their catabolism). The observation that cellular polyamines are typically elevated in plants under both short-term as well as long-term abiotic stress conditions is consistent with the possibility of their dual effects, i.e., being protectors from as well as perpetrators of stress damage to the cells. The observed increase in tolerance of plants to abiotic stress when their cellular contents are elevated by either exogenous treatment with polyamines or through genetic engineering with genes encoding polyamine biosynthetic enzymes is indicative of a protective role for them. However, through their catabolic production of hydrogen peroxide and acrolein, both strong oxidizers, they can potentially be the cause of cellular harm during stress. In fact, somewhat enigmatic but strong positive relationship between abiotic stress and foliar polyamines has been proposed as a potential biochemical marker of persistent environmental stress in forest trees in which phenotypic symptoms of stress are not yet visible. Such markers may help forewarn forest managers to undertake amelioration strategies before the appearance of visual symptoms of stress and damage at which stage it is often too late for implementing strategies for stress remediation and reversal of damage. This review provides a comprehensive and critical evaluation of the published literature on interactions between abiotic stress and polyamines in plants, and examines the experimental strategies used to understand the functional significance of this relationship with the aim of improving plant productivity, especially under conditions of abiotic stress. PMID:24847338

  19. Exogenous polyamines promote osteogenic differentiation by reciprocally regulating osteogenic and adipogenic gene expression.

    PubMed

    Lee, Mon-Juan; Chen, Yuhsin; Huang, Yuan-Pin; Hsu, Yi-Chiang; Chiang, Lan-Hsin; Chen, Tzu-Yu; Wang, Gwo-Jaw

    2013-12-01

    Polyamines are naturally occurring organic polycations that are ubiquitous in all organisms, and are essential for cell proliferation and differentiation. Although polyamines are involved in various cellular processes, their roles in stem cell differentiation are relatively unexplored. In this study, we found that exogenous polyamines, putrescine, spermidine, and spermine, promoted osteogenic differentiation of human bone marrow-derived mesenchymal stem cells (hBMSCs) without inducing cell death or apoptosis. Alkaline phosphatase (ALP) activity and the mRNA level of osteogenic genes, including Runx2, ALP, osteopontin, and osteocalcin, were up-regulated by exogenous polyamines. When hBMSCs were cultured at high cell density favoring adipocyte formation, exogenous polyamines resulted in down-regulation of adipogenic genes such as PPARγ, aP2, and adipsin. Extracellular matrix mineralization, a marker for osteoblast maturation, was enhanced in the presence of exogenous polyamines, while lipid accumulation, an indication of adipogenic differentiation, was attenuated. Exogenous polyamines increased the mRNA expression of polyamine-modulated factor 1 (PMF-1) and its downstream effector, spermidine/spermine N(1)-acetyltransferase (SSAT), while that of ornithine decarboxylase (ODC), the rate-limiting enzyme in polyamine biosynthesis, was suppressed. These results lead to possible connections between polyamine metabolism and osteogenic differentiation pathways. To summarize, this study provides evidence for the involvement of polyamines in osteogenic differentiation of hBMSCs, and is the first to demonstrate that osteogenic and adipogenic differentiation are reciprocally regulated by exogenous polyamines.

  20. Involvement of Polyamine Oxidase in Wound Healing12[W

    PubMed Central

    Angelini, Riccardo; Tisi, Alessandra; Rea, Giuseppina; Chen, Martha M.; Botta, Maurizio; Federico, Rodolfo; Cona, Alessandra

    2008-01-01

    Hydrogen peroxide (H2O2) is involved in plant defense responses that follow mechanical damage, such as those that occur during herbivore or insect attacks, as well as pathogen attack. H2O2 accumulation is induced during wound healing processes as well as by treatment with the wound signal jasmonic acid. Plant polyamine oxidases (PAOs) are H2O2 producing enzymes supposedly involved in cell wall differentiation processes and defense responses. Maize (Zea mays) PAO (ZmPAO) is a developmentally regulated flavoprotein abundant in primary and secondary cell walls of several tissues. In this study, we investigated the effect of wounding on ZmPAO gene expression in the outer tissues of the maize mesocotyl and provide evidence that ZmPAO enzyme activity, protein, and mRNA levels increased in response to wounding as well as jasmonic acid treatment. Histochemically detected ZmPAO activity especially intensified in the epidermis and in the wound periderm, suggesting a tissue-specific involvement of ZmPAO in wound healing. The role played by ZmPAO-derived H2O2 production in peroxidase-mediated wall stiffening events was further investigated by exploiting the in vivo use of N-prenylagmatine (G3), a selective and powerful ZmPAO inhibitor, representing a reliable diagnostic tool in discriminating ZmPAO-mediated H2O2 production from that generated by peroxidase, oxalate oxidase, or by NADPH oxidase activity. Here, we demonstrate that G3 inhibits wound-induced H2O2 production and strongly reduces lignin and suberin polyphenolic domain deposition along the wound, while it is ineffective in inhibiting the deposition of suberin aliphatic domain. Moreover, ZmPAO ectopic expression in the cell wall of transgenic tobacco (Nicotiana tabacum) plants strongly enhanced lignosuberization along the wound periderm, providing evidence for a causal relationship between PAO and peroxidase-mediated events during wound healing. PMID:17993545

  1. Carbonaceous materials water mixtures

    SciTech Connect

    Papalos, J.G.; Sinka, J.V.

    1985-04-30

    Particulate carbonaceous materials water mixtures are prepared by adding a condensate which is a condensation product of an aldehyde having from about 1 to about 7 carbon atoms, a benzene derivative such as benzene sulfonic acid, an alkyl benzene sulfonic acid having at least one alkyl group of from about 1 to about 20 carbon atoms and mixtures thereof, and optionally, and a naphthalene derivative such as naphthalene sulfonic acid, an alkyl naphthalene sulfonic acid having at least one alkyl group of from about 1 to about 12 carbon atoms and mixtures thereof. The condensate is added in an amount sufficient to reduce viscosity of the water mixture of carbonaceous materials, to stabilize carbonaceous materials in the water network and to improve pumpability. An acid form of the condensate or a salt may be added.

  2. Polyamine Catabolism Is Enhanced after Traumatic Brain Injury

    PubMed Central

    Zahedi, Kamyar; Huttinger, Francis; Morrison, Ryan; Murray-Stewart, Tracy; Casero, Robert A.

    2010-01-01

    Abstract Polyamines spermine and spermidine are highly regulated, ubiquitous aliphatic cations that maintain DNA structure and function as immunomodulators and as antioxidants. Polyamine homeostasis is disrupted after brain injuries, with concomitant generation of toxic metabolites that may contribute to secondary injuries. To test the hypothesis of increased brain polyamine catabolism after traumatic brain injury (TBI), we determined changes in catabolic enzymes and polyamine levels in the rat brain after lateral controlled cortical impact TBI. Spermine oxidase (SMO) catalyzes the degradation of spermine to spermidine, generating H2O2 and aminoaldehydes. Spermidine/spermine-N1-acetyltransferase (SSAT) catalyzes acetylation of these polyamines, and both are further oxidized in a reaction that generates putrescine, H2O2, and aminoaldehydes. In a rat cortical impact model of TBI, SSAT mRNA increased subacutely (6–24 h) after TBI in ipsilateral cortex and hippocampus. SMO mRNA levels were elevated late, from 3 to 7 days post-injury. Polyamine catabolism increased as well. Spermine levels were normal at 6 h and decreased slightly at 24 h, but were normal again by 72 h post-injury. Spermidine levels also decreased slightly (6–24 h), then increased by ∼50% at 72 h post-injury. By contrast, normally low putrescine levels increased up to sixfold (6–72 h) after TBI. Moreover, N-acetylspermidine (but not N-acetylspermine) was detectable (24–72 h) near the site of injury, consistent with increased SSAT activity. None of these changes were seen in the contralateral hemisphere. Immunohistochemical confirmation indicated that SSAT and SMO were expressed throughout the brain. SSAT-immunoreactivity (SSAT-ir) increased in both neuronal and nonneuronal (likely glial) populations ipsilateral to injury. Interestingly, bilateral increases in cortical SSAT-ir neurons occurred at 72 h post-injury, whereas hippocampal changes occurred only ipsilaterally

  3. Probing tRNA interaction with biogenic polyamines.

    PubMed

    Ouameur, Amin Ahmed; Bourassa, Philippe; Tajmir-Riahi, Heidar-Ali

    2010-10-01

    Biogenic polyamines are found to modulate protein synthesis at different levels. This effect may be explained by the ability of polyamines to bind and influence the secondary structure of tRNA, mRNA, and rRNA. We report the interaction between tRNA and the three biogenic polyamines putrescine, spermidine, spermine, and cobalt(III)hexamine at physiological conditions, using FTIR spectroscopy, capillary electrophoresis, and molecular modeling. The results indicated that tRNA was stabilized at low biogenic polyamine concentration, as a consequence of polyamine interaction with the backbone phosphate group. The main tRNA reactive sites for biogenic polyamine at low concentration were guanine-N7/O6, uracil-O2/O4, adenine-N3, and 2'OH of the ribose. At high polyamine concentration, the interaction involves guanine-N7/O6, adenine-N7, uracil-O2 reactive sites, and the backbone phosphate group. The participation of the polycation primary amino group, in the interaction and the presence of the hydrophobic contact, are also shown. The binding affinity of biogenic polyamine to tRNA molecule was in the order of spermine > spermidine > putrescine with K(Spm) = 8.7 × 10(5) M(-1), K(Spd) = 6.1 × 10(5) M(-1), and K(Put) = 1.0 × 10(5) M(-1), which correlates with their positively charged amino group content. Hill analysis showed positive cooperativity for the biogenic polyamines and negative cooperativity for cobalt-hexamine. Cobalt(III)hexamine contains high- and low-affinity sites in tRNA with K(1) = 3.2 × 10(5) M(-1) and K(2) = 1.7 × 10(5) M(-1), that have been attributed to the interactions with guanine-N7 sites and the backbone PO(2) group, respectively. This mechanism of tRNA binding could explain the condensation phenomenon observed at high Co(III) content, as previously shown in the Co(III)-DNA complexes.

  4. Contribution of polyamines metabolism and GABA shunt to chilling tolerance induced by nitric oxide in cold-stored banana fruit.

    PubMed

    Wang, Yansheng; Luo, Zisheng; Mao, Linchun; Ying, Tiejin

    2016-04-15

    Effect of exogenous nitric oxide (NO) on polyamines (PAs) catabolism, γ-aminobutyric acid (GABA) shunt, proline accumulation and chilling injury of banana fruit under cold storage was investigated. Banana fruit treated with NO sustained lower chilling injury index than the control. Notably elevated nitric oxide synthetase activity and endogenous NO level were observed in NO-treated banana fruit. PAs contents in treated fruit were significantly higher than control fruit, due to the elevated activities of arginine decarboxylase and ornithine decarboxylase. NO treatment increased the activities of diamine oxidase, polyamine oxidase and glutamate decarboxylase, while reduced GABA transaminase activity to lower levels compared with control fruit, which resulted the accumulation of GABA. Besides, NO treatment upregulated proline content and significantly enhanced the ornithine aminotransferase activity. These results indicated that the chilling tolerance induced by NO treatment might be ascribed to the enhanced catabolism of PAs, GABA and proline.

  5. The Mixture of Salvianolic Acids from Salvia miltiorrhiza and Total Flavonoids from Anemarrhena asphodeloides Attenuate Sulfur Mustard-Induced Injury.

    PubMed

    Li, Jianzhong; Chen, Linlin; Wu, Hongyuan; Lu, Yiming; Hu, Zhenlin; Lu, Bin; Zhang, Liming; Chai, Yifeng; Zhang, Junping

    2015-10-15

    Sulfur mustard (SM) is a vesicating chemical warfare agent used in numerous military conflicts and remains a potential chemical threat to the present day. Exposure to SM causes the depletion of cellular antioxidant thiols, mainly glutathione (GSH), which may lead to a series of SM-associated toxic responses. MSTF is the mixture of salvianolic acids (SA) of Salvia miltiorrhiza and total flavonoids (TFA) of Anemarrhena asphodeloides. SA is the main water-soluble phenolic compound in Salvia miltiorrhiza. TFA mainly includes mangiferin, isomangiferin and neomangiferin. SA and TFA possess diverse activities, including antioxidant and anti-inflammation activities. In this study, we mainly investigated the therapeutic effects of MSTF on SM toxicity in Sprague Dawley rats. Treatment with MSTF 1 h after subcutaneous injection with 3.5 mg/kg (equivalent to 0.7 LD50) SM significantly increased the survival levels of rats and attenuated the SM-induced morphological changes in the testis, small intestine and liver tissues. Treatment with MSTF at doses of 60 and 120 mg/kg caused a significant (p<0.05) reversal in SM-induced GSH depletion. Gene expression profiles revealed that treatment with MSTF had a dramatic effect on gene expression changes caused by SM. Treatment with MSTF prevented SM-induced differential expression of 93.8% (973 genes) of 1037 genes. Pathway enrichment analysis indicated that these genes were mainly involved in a total of 36 pathways, such as the MAPK signaling pathway, pathways in cancer, antigen processing and presentation. These data suggest that MSTF attenuates SM-induced injury by increasing GSH and targeting multiple pathways, including the MAPK signaling pathway, as well as antigen processing and presentation. These results suggest that MSTF has the potential to be used as a potential therapeutic agent against SM injuries.

  6. Urinary Tetrabromobenzoic Acid (TBBA) as a Biomarker of Exposure to the Flame Retardant Mixture Firemaster® 550

    PubMed Central

    Hoffman, Kate; Fang, Mingliang; Horman, Brian; Patisaul, Heather B.; Garantziotis, Stavros; Birnbaum, Linda S.

    2014-01-01

    Background: Firemaster® 550 (FM550) is commonly added to residential furniture to reduce its flammability. Recent toxicological evidence suggests that FM550 may be endocrine disrupting and obesogenic. Objectives: Our objectives were to develop methods to assess exposure to FM550 in human populations and to identify potential routes of exposure. Methods: Using mass spectrometry methods, we developed a method to measure 2,3,4,5-tetrabromobenzoic acid (TBBA), a urinary metabolite of the major brominated FM550 component 2-ethylhexyl-2,3,4,5-tetrabromobenzoate (TBB). The method was applied to a cohort of adult volunteers (n = 64). Participants completed questionnaires, provided urine and handwipe samples, and collected dust samples from their homes. We measured TBB and the other major brominated FM550 component, bis(2-ethylhexyl)-2,3,4,5-tetrabromophthalate (TBPH), in paired dust and handwipe samples. Results: TBBA was detected in 72.4% of urine samples. Although TBBA is a rapidly formed metabolite, analyses indicated moderate temporal reliability (interclass correlation coefficient = 0.56; 95% confidence interval: 0.46, 0.66). TBB and TBPH were detected frequently in dust samples [geometric mean (GM) = 315.1 and 364.7 ng/g, respectively] and in handwipes (GM = 31.4 and 23.4 ng, respectively). Levels of TBB and TBPH in dust were positively correlated with levels in handwipes. In addition, levels of TBB in handwipes were positively correlated with urinary TBBA. Results suggest frequent hand washing may reduce the mass of TBB on participants’ hands and reduce urinary TBBA levels. Conclusions: Cumulatively, our data indicate that exposures to FM550 are widespread and that the home environment may be an important source of exposure. Urinary TBBA provides a potentially useful biomarker of FM550 exposure for epidemiologic studies. Citation: Hoffman K, Fang M, Horman B, Patisaul HB, Garantziotis S, Birnbaum LS, Stapleton HM. 2014. Urinary tetrabromobenzoic acid (TBBA) as a

  7. DNA Interaction Studies of Selected Polyamine Conjugates

    PubMed Central

    Szumilak, Marta; Merecz, Anna; Strek, Malgorzata; Stanczak, Andrzej; Inglot, Tadeusz W.; Karwowski, Boleslaw T.

    2016-01-01

    The interaction of polyamine conjugates with DNA double helix has been studied. Binding properties were examined by ethidium bromide (EtBr) displacement and DNA unwinding/topoisomerase I/II (Topo I/II) activity assays, as well as dsDNA thermal stability studies and circular dichroism spectroscopy. Genotoxicity of the compounds was estimated by a comet assay. It has been shown that only compound 2a can interact with dsDNA via an intercalative binding mode as it displaced EtBr from the dsDNA-dye complex, with Kapp = 4.26 × 106 M−1; caused an increase in melting temperature; changed the circular dichroism spectrum of dsDNA; converted relaxed plasmid DNA into a supercoiled molecule in the presence of Topo I and reduced the amount of short oligonucleotide fragments in the comet tail. Furthermore, preliminary theoretical study has shown that interaction of the discussed compounds with dsDNA depends on molecule linker length and charge distribution over terminal aromatic chromophores. PMID:27657041

  8. Possible prebiotic significance of polyamines in the condensation, protection, encapsulation, and biological properties of DNA

    NASA Technical Reports Server (NTRS)

    Baeza, I.; Ibanez, M.; Wong, C.; Chavez, P.; Gariglio, P.; Oro, J.

    1991-01-01

    Some properties of DNA condensed with spermidine have been compared with the properties of DNA condensed with Co3+(NH3)6 to determine whether condensation of DNA with these trivalent cations protects DNA against the action of DNase I and increases transcription and encapsulation of DNA into liposomes. It was shown that DNA condensed with Co3+(NH3)6 was resistant to the action of the endonuclease DNase I such as DNA condensed with spermidine was. However, DNA condensed with Co3+(NH3)6 was significantly less active in transcription with the E. coli RNA polymerase than DNA-spermidine condensed forms. In addition, it was demonstrated that both compacted forms of DNA were more efficiently encapsulated into neutral liposomes; however, negatively, charged liposomes were scarcely formed in the presence of DNA condensed with Co3+(NH3)6. These experiments and the well documented properties of polyamines increasing the resistance to radiations and hydrolysis of nucleic acids, as well as their biological activities, such as replication, transcription, and translation, together with the low concentration of Co3+ in the environment, lead us to propose spermidine as a plausible prebiotic DNA condensing agent rather than Co3+ and the basic proteins proposed by other authors. Then, we consider the possible role and relevance of the polyamine-nucleic acids complexes in the evolution of life.

  9. Evaluation of five methods for derivatization and GC determination of a mixture of very long chain fatty acids (C24:0-C36:0).

    PubMed

    Antolín, Ernesto Méndez; Delange, David Marrero; Canavaciolo, Víctor González

    2008-01-07

    D003 is a new active ingredient consisting of a mixture of very long chain saturated fatty acids (C(24:0)-C(36:0)) in a definite proportion, which shows antioxidant, antiosteoporotic, antiplatelet and cholesterol-lowering effects in experimental models. Five derivatization methods for determining these fatty acids by gas chromatography (GC), using diazomethane, sulphuric acid-methanol, hydrochloric acid-methanol, boron trifluoride-methanol and N-methyl-N-trimethylsilyltrifluoroacetamide were evaluated. GC analysis was carried out using a BPX-5 wide-bore column and 1-nonadecanoic acid (C(19:0)) as internal standard. Methods were similar on account of the fatty acid content determined (84.2-86.6%). However, whereas the hydrochloric acid-methanol method needed 90 min to complete the derivatization, the other methods only required 10 min. Considering costs, speed, safety and GC response, the method using sulphuric acid-methanol was found the most appropriate for determining these fatty acids. The validation of this method: linearity over a range 40-160%, accuracy assessed through a recovery study, precision within day and inter-day, and specificity, even for samples subject to stress conditions, proved it is suitable for quality control and stability studies of the very long chain fatty acids composing this active ingredient.

  10. Pregnancy loss and eye malformations in offspring of F344 rats following gestational exposure to mixtures of regulated trihalomethanes and haloacetic acids.

    PubMed

    Narotsky, Michael G; Best, Deborah S; McDonald, Anthony; Godin, Elizabeth A; Hunter, E Sidney; Simmons, Jane Ellen

    2011-01-01

    Chlorination of drinking water yields hundreds of disinfection by-products (DBPs). Among the DBPs, four trihalomethanes (THMs; chloroform, bromodichloromethane, chlorodibromomethane, bromoform) and five haloacetic acids (HAAs; chloroacetic, dichloroacetic, trichloroacetic, bromoacetic, and dibromoacetic acid) are U.S. EPA regulated. We assessed the combined toxicity of these DBPs. F344 rats were treated with mixtures of the four THMs (THM4), the five HAAs (HAA5), or nine DBPs (DBP9; THM4+HAA5). Mixtures were administered in 10% Alkamuls(®) EL-620 daily by gavage on gestation days 6-20. Litters were examined postnatally. All three mixtures caused pregnancy loss at ≥ 613 μmol/kg/day. In surviving litters, resorption rates were increased in groups receiving HAA5 at 615 μmol/kg/day and DBP9 at 307 μmol/kg/day. HAA5 caused eye malformations (anophthalmia, microphthalmia) at ≥ 308 μmol/kg/day. Thus, both HAAs and THMs contributed to DBP9-induced pregnancy loss. The presence of THMs in the full mixture, however, appeared to reduce the incidence of HAA-induced eye defects.

  11. BET, thermal degradation, and FTIR spectras of triazine polyamine polymers.

    PubMed

    Can, Mustafa

    2017-04-01

    Here we show effect of the polyamine polymer chain length to BET isotherms. According to IUPAC classification [1], all three polymers are fitting type 1 physical adsorption isotherm with H3 hysteresis (except for EDA having H2 hysteresis). Moreover, TG and TGA analysis of polymers triazine-ethylenediamine (EDA) and triazine-triethylenetetramine (TETA) are provided. Due to the similarities of the structure, main decomposition temperatures are close to each other (between 593 K and 873 K). In order to understand change of FTIR spectra with adsorption and stripping Au(III), fresh, Au(III) adsorbed and recycled spectras of polymers measured. For further discussions about the effect of chain length to adsorption of Au(III) onto triazine polyamine polymer particles "Au (III) Uptake by Triazine Polyamine Polymers: Mechanism, Kinetic and Equilibrium Studies" Can et al. [2] (article in press).

  12. Polyamine content of long-keeping alcobaca tomato fruit.

    PubMed

    Dibble, A R; Davies, P J; Mutschler, M A

    1988-02-01

    Fruit of tomato landrace Alcobaca, containing the recessive allele alc, ripen more slowly, with a reduced level of ethylene production, and have prolonged keeping qualities. The levels of polyamines in pericarp tissues of alc and ;wild type' Alc (cv Rutgers and Alcobaca-red) fruit were measured by HPLC in relation to ripening. Putrescine was the predominant polyamine with a lower content of spermidine, while spermine was just detectable. The level of putrescine was high at the immature green stage and declined in the mature green stage. In Alc fruit the decline persisted but in alc fruit the putrescine level increased during ripening to a level similar to that present at the immature green stage. There was no pronounced change or difference in spermidine levels. The enhanced polyamine level in alc fruit may account for their ripening and storage characteristics.

  13. Targeting polyamine metabolism and function in cancer and other hyperproliferative diseases.

    PubMed

    Casero, Robert A; Marton, Laurence J

    2007-05-01

    The polyamines spermidine and spermine and their diamine precursor putrescine are naturally occurring, polycationic alkylamines that are essential for eukaryotic cell growth. The requirement for and the metabolism of polyamines are frequently dysregulated in cancer and other hyperproliferative diseases, thus making polyamine function and metabolism attractive targets for therapeutic intervention. Recent advances in our understanding of polyamine function, metabolic regulation, and differences between normal cells and tumour cells with respect to polyamine biology, have reinforced the interest in this target-rich pathway for drug development.

  14. The evolution of a superbug: how Staphylococcus aureus overcomes its unique susceptibility to polyamines.

    PubMed

    Anzaldi, Laura L; Skaar, Eric P

    2011-10-01

    Polyamines are ubiquitous compounds thought to be synthesized by and required for all life. The manuscript published in this issue by Joshi and colleagues upsets this dogma by identifying several bacterial species that do not make polyamines, and in some cases do not require polyamines for growth. One such species is the significant human pathogen Staphylococcus aureus, which is shown to be uniquely sensitive to polyamines. By unravelling the mechanisms of staphylococcal polyamine toxicity and tolerance, Joshi et al. (2011) provide insights into how the most virulent strains of S. aureus have evolved to be more fit during infection.

  15. Polyamine Metabolism in Embryogenic Cells of Daucus carota

    PubMed Central

    Montague, Michael J.; Koppenbrink, Joan W.; Jaworski, Ernest G.

    1978-01-01

    Changes in the metabolism of polyamines, which seem to be involved in transcription and translation in animal systems, have been studied in cultured cells of Daucus carota (carrot) undergoing embryogenesis. Putrescine levels were elevated by as much as 2-fold over the control within 24 hours after transfer of the cells to embryogenic medium. Spermidine levels were elevated also but spermine levels appeared to be lower in embryogenic cells. Embryogenic cells incorporated [14C]arginine into putrescine at two times the rate of control cells. These changes suggest that polyamines may be involved in cellular differentiation during embryogenesis. PMID:16660531

  16. General synthesis of β-alanine-containing spider polyamine toxins and discovery of nephila polyamine toxins 1 and 8 as highly potent inhibitors of ionotropic glutamate receptors.

    PubMed

    Lucas, Simon; Poulsen, Mette H; Nørager, Niels G; Barslund, Anne F; Bach, Tinna B; Kristensen, Anders S; Strømgaard, Kristian

    2012-11-26

    Certain spiders contain large pools of polyamine toxins, which are putative pharmacological tools awaiting further discovery. Here we present a general synthesis strategy for this class of toxins and prepare five structurally varied polyamine toxins. Electrophysiological testing at three ionotropic glutamate receptor subtypes reveals that two of these, Nephila polyamine toxins 1 (NPTX-1) and 8 (NPTX-8), comprise intriguing pharmacological activities by having subnanomolar IC(50) values at kainate receptors.

  17. Content of phenolic compounds and free polyamines in black chokeberry (Aronia melanocarpa) after application of polyamine biosynthesis regulators.

    PubMed

    Hudec, Jozef; Bakos, Dusan; Mravec, Dusan; Kobida, L'ubomír; Burdová, Maria; Turianica, Ivan; Hlusek, Jaroslav

    2006-05-17

    The total contents of anthocyanins, flavonoids, and phenolics in 60 samples of black chokeberries (Aronia melanocarpa), after treating with catabolites of polyamine biosynthesis (KPAb) and ornithine decarboxylase inhibitor, were analyzed spectrophotometrically, and quercetin and free polyamine contents were analyzed by RP-HPLC with UV detection. The average total contents of the individual substances and phenolic subgroups in control berries were as follows (mg x kg(-1)): anthocyanines, 6408; flavonoids, 664; phenolics, 37,600; quercetin, 349. KPAb decreased total contents of anthocyanines and phenolics only slightly but significantly increased the content of flavonoids. This caused an important change in the abundance of flavonoids in the pigment complex. The absolute content of quercetin was increased, but its ratio to flavonoids content was decreased. Ornithine decarboxylase inhibitor had a markedly different effect as it significantly increased total content of anthocyanins and total phenolics, inhibited the total content of free polyamines, and stimulated the processes of saccharides transformation to phenolic pigments.

  18. Induction of phase 2 enzymes by serum oxidized polyamines through activation of Nrf2: effect of the polyamine metabolite acrolein.

    PubMed

    Kwak, Mi-Kyoung; Kensler, Thomas W; Casero, Robert A

    2003-06-06

    The naturally occurring polycationic polyamines including putrescine, spermidine, and spermine play an important role in cell growth, differentiation, and gene expression. However, circulating polyamines are potential substrates for several oxidizing enzymes including copper-containing serum amine oxidase. These enzymes are capable of oxidizing serum polyamines to several toxic metabolites including aldehydes and H(2)O(2). In this study, we investigated the effects of polyamines as inducers of phase 2 enzymes and other genes that promote cell survival in a cell culture system in the presence of bovine serum. Spermidine and spermine (50 microM) increased NAD(P)H quinone oxidoreductase (NQO1) activity up to 3-fold in murine keratinocyte PE cells. Transcript levels for glutathione S-transferase (GST) A1, GST M1, NQO1, gamma-glutamylcysteine ligase regulatory subunit, and UDP-glucuronyltransferase 1A6 were significantly increased by spermidine and this effect was mediated through the antioxidant response element (ARE). The ARE from the mouse GST A1 promoter was activated about 9-fold by spermine and 5-fold by spermidine treatment, but could be inhibited by the amine oxidase inhibitor, aminoguanidine, suggesting that acrolein or hydrogen peroxide generated from polyamines by serum amine oxidase may be mediators for phase 2 enzyme induction. Elevations of ARE-luciferase expression and NQO1 enzyme activity by spermidine were not affected by catalase, while both were completely repressed by aldehyde dehydrogenase treatment. Direct addition of acrolein to PE cells induced multiple phase 2 genes and elevated nuclear levels of Nrf2, a transcription factor that binds to the ARE. Expression of mutant Nrf2 repressed the activation of the ARE-luciferase reporter by polyamines and acrolein. These results indicate that spermidine and spermine increase the expression of phase 2 genes in cells grown in culture through activation of the Nrf2-ARE pathway by generating the sulfhydryl

  19. Polyamine metabolism in flax in response to treatment with pathogenic and non–pathogenic Fusarium strains

    PubMed Central

    Wojtasik, Wioleta; Kulma, Anna; Namysł, Katarzyna; Preisner, Marta; Szopa, Jan

    2015-01-01

    Flax crop yield is limited by various environmental stress factors, but the largest crop losses worldwide are caused by Fusarium infection. Polyamines are one of the many plant metabolites possibly involved in the plant response to infection. However, in flax plants the polyamine composition, genes involved in polyamine synthesis, and in particular their regulation, were previously unknown. The aim of this study was to investigate the polyamine synthesis pathway in flax and its involvement in response to pathogen infection. It is well established that polyamines are essential for the growth and development of both plants and fungi, but their role in pathogen infection still remains unknown. In our study we correlated the expression of genes involved in polyamine metabolism with the polyamine levels in plant tissues and compared the results for flax seedlings treated with two pathogenic and one non-pathogenic strains of Fusarium. We observed an increase in the expression of genes participating in polyamine synthesis after fungal infection, and it was reflected in an increase of polyamine content in the plant tissues. The highest level of mRNA was characteristic for ornithine decarboxylase during infection with all tested, pathogenic and non-pathogenic, Fusarium strains and the arginine decarboxylase gene during infection with the pathogenic strain of Fusarium culmorum. The main polyamine identified in the flax seedlings was putrescine, and its level changed the most during infection. Moreover, the considerable increase in the contents of cell wall-bound polyamines compared to the levels of free and conjugated polyamines may indicate that their main role during pathogen infection lies in strengthening of the cell wall. In vitro experiments showed that the polyamines inhibit Fusarium growth, which suggests that they play an important role in plant defense mechanisms. Furthermore, changes in metabolism and content of polyamines indicate different defense mechanisms

  20. The natural polyamines spermidine and spermine prevent bone loss through preferential disruption of osteoclastic activation in ovariectomized mice

    PubMed Central

    Yamamoto, Tomomi; Hinoi, Eiichi; Fujita, Hiroyuki; Iezaki, Takashi; Takahata, Yoshifumi; Takamori, Misa; Yoneda, Yukio

    2012-01-01

    BACKGROUND AND PURPOSE Although naturally occurring polyamines are indispensable for a variety of cellular events in eukaryotic cells, little attention has been paid to their physiological and pathological significance in bone remodelling to date. In this study, we evaluated the pharmacological properties of several natural polyamines on the functionality and integrity of bone in both in vitro and in vivo experiments. EXPERIMENTAL APPROACH Mice were subjected to ovariectomy (OVX) and subsequent oral supplementation with either spermidine or spermine for determination of the bone volume together with different parameters regarding bone formation and resorption by histomorphometric analyses in vivo. Pre-osteoclasts were cultured with receptor activator of NF-κB ligand (RANKL), with or without spermidine and spermine to determine cellular maturation by tartrate-resistant acid phosphatase (TRAP) staining and cellular viability by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide reduction in vitro. KEY RESULTS Spermidine or spermine, given in drinking water for 28 days, significantly prevented the increased osteoclast surface/bone surface ratio and the reduced bone volume following OVX in mice. Either spermidine or spermine significantly inhibited the increased number of multinucleated TRAP-positive cells in osteoclasts cultured with RANKL in a concentration-dependent manner without affecting cell survival. CONCLUSIONS AND IMPLICATIONS The natural polyamines spermidine and spermine prevented OVX-induced bone loss through the disruption of differentiation and maturation of osteoclasts, rather than affecting osteoblasts. The supplementation with these natural polyamines could be beneficial for the prophylaxis as well as therapy of metabolic bone diseases such as post-menopausal osteoporosis. PMID:22250848

  1. A Nascent Peptide Signal Responsive to Endogenous Levels of Polyamines Acts to Stimulate Regulatory Frameshifting on Antizyme mRNA*

    PubMed Central

    Yordanova, Martina M.; Wu, Cheng; Andreev, Dmitry E.; Sachs, Matthew S.; Atkins, John F.

    2015-01-01

    The protein antizyme is a negative regulator of cellular polyamine concentrations from yeast to mammals. Synthesis of functional antizyme requires programmed +1 ribosomal frameshifting at the 3′ end of the first of two partially overlapping ORFs. The frameshift is the sensor and effector in an autoregulatory circuit. Except for Saccharomyces cerevisiae antizyme mRNA, the frameshift site alone only supports low levels of frameshifting. The high levels usually observed depend on the presence of cis-acting stimulatory elements located 5′ and 3′ of the frameshift site. Antizyme genes from different evolutionary branches have evolved different stimulatory elements. Prior and new multiple alignments of fungal antizyme mRNA sequences from the Agaricomycetes class of Basidiomycota show a distinct pattern of conservation 5′ of the frameshift site consistent with a function at the amino acid level. As shown here when tested in Schizosaccharomyces pombe and mammalian HEK293T cells, the 5′ part of this conserved sequence acts at the nascent peptide level to stimulate the frameshifting, without involving stalling detectable by toe-printing. However, the peptide is only part of the signal. The 3′ part of the stimulator functions largely independently and acts at least mostly at the nucleotide level. When polyamine levels were varied, the stimulatory effect was seen to be especially responsive in the endogenous polyamine concentration range, and this effect may be more general. A conserved RNA secondary structure 3′ of the frameshift site has weaker stimulatory and polyamine sensitizing effects on frameshifting. PMID:25998126

  2. Enthalpy-entropy compensation for the solubility of drugs in solvent mixtures: paracetamol, acetanilide, and nalidixic acid in dioxane-water.

    PubMed

    Bustamante, P; Romero, S; Pena, A; Escalera, B; Reillo, A

    1998-12-01

    In earlier work, a nonlinear enthalpy-entropy compensation was observed for the solubility of phenacetin in dioxane-water mixtures. This effect had not been earlier reported for the solubility of drugs in solvent mixtures. To gain insight into the compensation effect, the behavior of the apparent thermodynamic magnitudes for the solubility of paracetamol, acetanilide, and nalidixic acid is studied in this work. The solubility of these drugs was measured at several temperatures in dioxane-water mixtures. DSC analysis was performed on the original powders and on the solid phases after equilibration with the solvent mixture. The thermal properties of the solid phases did not show significant changes. The three drugs display a solubility maximum against the cosolvent ratio. The solubility peaks of acetanilide and nalidixic acid shift to a more polar region at the higher temperatures. Nonlinear van't Hoff plots were observed for nalidixic acid whereas acetanilide and paracetamol show linear behavior at the temperature range studied. The apparent enthalpies of solution are endothermic going through a maximum at 50% dioxane. Two different mechanisms, entropy and enthalpy, are suggested to be the driving forces that increase the solubility of the three drugs. Solubility is entropy controlled at the water-rich region (0-50% dioxane) and enthalpy controlled at the dioxane-rich region (50-100% dioxane). The enthalpy-entropy compensation analysis also suggests that two different mechanisms, dependent on cosolvent ratio, are involved in the solubility enhancement of the three drugs. The plots of deltaH versus deltaG are nonlinear, and the slope changes from positive to negative above 50% dioxane. The compensation effect for the thermodynamic magnitudes of transfer from water to the aqueous mixtures can be described by a common empirical nonlinear relationship, with the exception of paracetamol, which follows a separate linear relationship at dioxane ratios above 50%. The

  3. Photochemical internalization-mediated nonviral gene transfection: polyamine core-shell nanoparticles as gene carrier

    NASA Astrophysics Data System (ADS)

    Zamora, Genesis; Wang, Frederick; Sun, Chung-Ho; Trinidad, Anthony; Kwon, Young Jik; Cho, Soo Kyung; Berg, Kristian; Madsen, Steen J.; Hirschberg, Henry

    2014-10-01

    The overall objective of the research was to investigate the utility of photochemical internalization (PCI) for the enhanced nonviral transfection of genes into glioma cells. The PCI-mediated introduction of the tumor suppressor gene phosphatase and tensin homolog (PTEN) or the cytosine deaminase (CD) pro-drug activating gene into U87 or U251 glioma cell monolayers and multicell tumor spheroids were evaluated. In the study reported here, polyamine-DNA gene polyplexes were encapsulated in a nanoparticle (NP) with an acid degradable polyketal outer shell. These NP synthetically mimic the roles of viral capsid and envelope, which transport and release the gene, respectively. The effects of PCI-mediated suppressor and suicide genes transfection efficiency employing either "naked" polyplex cores alone or as NP-shelled cores were compared. PCI was performed with the photosensitizer AlPcS2a and λ=670-nm laser irradiance. The results clearly demonstrated that the PCI can enhance the delivery of both the PTEN or CD genes in human glioma cell monolayers and multicell tumor spheroids. The transfection efficiency, as measured by cell survival and inhibition of spheroid growth, was found to be significantly greater at suboptimal light and DNA levels for shelled NPs compared with polyamine-DNA polyplexes alone.

  4. Self-assembled microstructures from 1,2-ethanediol suspensions of pure and binary mixtures of neutral and acidic biological galactosylceramides.

    PubMed

    Archibald, D D; Mann, S

    1994-01-01

    Optical and electron microscopy were employed to characterize microstructures formed by thermal mechanical treatment of glycol suspensions of various pure and binary mixtures of the brain-derived galactosphingolipids hydroxy fatty acid cerebroside (HFA-Cer), non-hydroxy fatty acid cerebroside (NFA-Cer) and sulfatide (S-Cer). Negative staining indicated some new features of the neutral cerebroside suspensions in glycol. HFA-Cer formed a small fraction of both unilamellar cylinders (ULCs) (lumina ca. 27 nm) and giant multilamellar cochleates in addition to the typical nonhelical multilamellar cylinders (MLCs) (lumina ca. 10-30 nm). NFA-Cer formed a gel composed of a significant fraction of very long ULCs (lumina ca. 17 nm) without helical substructure, in addition to multilamellar helical structures such as ribbons and cylinders (lumina ca. 70 nm). Anisotropic lamellar micelle-shards of NFA-Cer were also detected by negative staining. S-Cer formed short ULCs (lumina ca. 44 nm) with no obvious helical substructure. Complex mixture data are thought to result from thermodynamic and kinetic factors. HFA-Cer is highly insoluble and promotes a network of rigid intralamellar hydrogen bonding that tends to exclude other lipids. NFA-Cer stabilizes helical defects in the lamellae, and S-Cer enhances disorder or micellization. The processes of microstructure nucleation and lipid phase separation were affected by mixtures such that metastable microstructures were trapped or the length of lamellar cylinders was altered.

  5. S-adenosyl-L-methionine usage during climacteric ripening of tomato in relation to ethylene and polyamine biosynthesis and transmethylation capacity.

    PubMed

    Van de Poel, Bram; Bulens, Inge; Oppermann, Yasmin; Hertog, Marten L A T M; Nicolai, Bart M; Sauter, Margret; Geeraerd, Annemie H

    2013-06-01

    S-adenosyl-L-methionine (SAM) is the major methyl donor in cells and it is also used for the biosynthesis of polyamines and the plant hormone ethylene. During climacteric ripening of tomato (Solanum lycopersicum 'Bonaparte'), ethylene production rises considerably which makes it an ideal object to study SAM involvement. We examined in ripening fruit how a 1-MCP treatment affects SAM usage by the three major SAM-associated pathways. The 1-MCP treatment inhibited autocatalytic ethylene production but did not affect SAM levels. We also observed that 1-(malonylamino)cyclopropane-1-carboxylic acid formation during ripening is ethylene dependent. SAM decarboxylase expression was also found to be upregulated by ethylene. Nonetheless polyamine content was higher in 1-MCP-treated fruit. This leads to the conclusion that the ethylene and polyamine pathway can operate simultaneously. We also observed a higher methylation capacity in 1-MCP-treated fruit. During fruit ripening substantial methylation reactions occur which are gradually inhibited by the methylation product S-adenosyl-L-homocysteine (SAH). SAH accumulation is caused by a drop in adenosine kinase expression, which is not observed in 1-MCP-treated fruit. We can conclude that tomato fruit possesses the capability to simultaneously consume SAM during ripening to ensure a high rate of ethylene and polyamine production and transmethylation reactions. SAM usage during ripening requires a complex cellular regulation mechanism in order to control SAM levels.

  6. Polyamine metabolism and osmotic stress. I. Relation to protoplast viability

    NASA Technical Reports Server (NTRS)

    Tiburcio, A. F.; Masdeu, M. A.; Dumortier, F. M.; Galston, A. W.

    1986-01-01

    Cereal leaves subjected to the osmotica routinely used for protoplast isolation show a rapid increase in arginine decarboxylase activity, a massive accumulation of putrescine, and slow conversion of putrescine to the higher polyamines, spermidine and spermine (HE Flores, AW Galston 1984 Plant Physiol 75: 102). Mesophyll protoplasts from these leaves, which have a high putrescine:polyamine ratio, do not undergo sustained division. By contrast, in Nicotiana, Capsicum, Datura, Trigonella, and Vigna, dicot genera that readily regenerate plants from mesophyll protoplasts, the response of leaves to osmotic stress is opposite to that in cereals. Putrescine titer as well as arginine and ornithine decarboxylase activities decline in these osmotically stressed dicot leaves, while spermidine and spermine titers increase. Thus, the putrescine:polyamine ratio in Vigna protoplasts, which divide readily, is 4-fold lower than in oat protoplasts, which divide poorly. We suggest that this differing response of polyamine metabolism to osmotic stress may account in part for the failure of cereal mesophyll protoplasts to develop readily in vitro.

  7. HIGHER POLYAMINES RESTORE AND INVIGORATE METABOLIC MEMORY IN RIPENING FRUIT

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Polyamines (PAs) are ubiquitous, biogenic amines that have been implicated in diverse cellular functions in most living organisms. Ever since spermine (Spm) phosphate crystals were isolated over three centuries ago, scientists have kept busy in unraveling the mystery behind biological roles of Spm a...

  8. Polyamines and cell proliferation in the sea star Pycnopodia helianthoides.

    PubMed

    Asotra, S; Mladenov, P V; Burke, R D

    1988-01-01

    1. Diamines (putrescine and cadaverine) and polyamines (spermidine and spermine) were extracted from tissues of the sea star Pycnopodia helianthoides, separated and quantitated using reversed-phase high-performance liquid chromatography (RP-HPLC). Simultaneous measurements of levels of protein and DNA and rates of incorporation of 14C-thymidine were carried out. 2. The most abundant polyamine in tissues was spermidine (0.3873-2.5282 nmol/mg tissue) followed by spermine (0.103-1.5517 nmol/mg tissue), putrescine (0.2096-0.5322 nmol/mg tissue) and cadaverine (0.022-0.6064 nmol/mg tissue). 3. An unknown molecule with derivatization and elution behaviour similar to that of polyamine standards was detected in all tissues. 4. Protein levels ranged from 20.47 mg/g tissue in the body wall to 48.44 mg/g tissue in the pyloric caecum. 5. DNA levels were lowest in the ovary (0.25 mg/g tissue) and highest in the testis (5.62 mg/g tissue). 6. Incorporation of 14C-thymidine was highest in the testis. Testicular tissue had the highest spermidine/spermine ratio (5.4). A significant correlation between the spermidine/spermine ratio and 14C-thymidine incorporation (expressed either as DPM/g tissue or DPM/mg protein) suggests that polyamines are implicated in the regulation of cell proliferation in the sea star P. helianthoides.

  9. Polyamine levels and tomato fruit development: possible interaction with ethylene.

    PubMed

    Saftner, R A; Baldi, B G

    1990-02-01

    Fruits of tomato, Lycopersicon esculentum Mill. cv Liberty, ripen slowly and have a prolonged keeping quality. Ethylene production and the levels of polyamines in pericarp of cv Liberty, Pik Red, and Rutgers were measured in relation to fruit development. Depending on the stage of fruit development, Liberty produced between 16 and 38% of the ethylene produced by Pik Red and Rutgers. The polyamines putrescine, spermidine, and spermine were present in all cultivars. Cadaverine was detected only in Rutgers. Levels of putrescine and spermidine declined between the immature and mature green stages of development and prior to the onset of climacteric ethylene production. In Pik Red and Rutgers, the decline persisted, whereas in Liberty, the putrescine level increased during ripening. Ripe pericarp of Liberty contained about three and six times more free (unconjugated) polyamines than Pik Red and Rutgers, respectively. No pronounced changes in spermidine or cadaverine occurred during ripening. The increase in the free polyamine level in ripe pericarp of Liberty may account for the reduction of climacteric ethylene production, and prolonged storage life.

  10. Phase behavior of binary mixture systems of saturated-unsaturated mixed-acid triacylglycerols: effects of glycerol structures and chain-chain interactions.

    PubMed

    Bayés-García, Laura; Calvet, Teresa; Cuevas-Diarte, Miquel Àngel; Ueno, Satoru; Sato, Kiyotaka

    2015-03-26

    We systematically examined the phase behavior of binary mixtures of mixed-acid triacylglycerols (TAGs) containing palmitic and oleic acid moieties 1,3-dioleoyl-2-palmitoyl-glycerol (OPO), 1,2-dipalmitoyl-3-oleoyl-rac-glycerol (PPO), and 1,2-dioleoyl-3-palmitoyl-rac-glycerol (OOP), which are widely present in natural fats and are employed in the food, pharmaceutical, and cosmetic industries. Differential scanning calorimetry and X-ray diffraction methods were applied to observe the mixing behavior of PPO/OPO, OOP/OPO, and PPO/OOP under metastable and stable conditions. The results led to three conclusions: (1) Eutectic behavior was observed in PPO/OPO. (2) Molecular compound (MC) crystals were formed in the mixtures of OOP/OPO and PPO/OOP. (3) However, the MC crystals occurred only under metastable conditions and tended to separate into component TAGs to form eutectic mixture systems after 17 months of incubation. These results were contrary to those of previous studies on 1,3-dipalmitoyl-2-oleoyl glycerol (POP)/OPO and POP/PPO in which the MC crystals were thermodynamically stable. We determined that specific molecular interactions may cause this different phase behavior (stability of POP/OPO and POP/PPO MC crystals and metastability of OOP/OPO and PPO/OOP MC crystals). All results confirm the significant effects of molecular structures of glycerol groups, interactions of fatty acid chains, and polymorphism of the component TAGs on the mixing behavior of mixed-acid TAGs.

  11. Preparation and properties of films cast from mixtures of poly(vinyl alcohol) and submicron particles prepared from amylose-palmitic acid inclusion complexes.

    PubMed

    Fanta, George F; Selling, Gordon W; Felker, Frederick C; Kenar, James A

    2015-05-05

    The use of starch in polymer composites for film production has been studied for increasing biodegradability, improving film properties and reducing cost. In this study, submicron particles were prepared from amylose-sodium palmitate complexes both by rapidly cooling jet-cooked starch-palmitic acid mixtures and by acidifying solutions of starch-sodium palmitate complexes. Films were cast containing poly(vinyl alcohol) (PVOH) with up to 50% starch particles. Tensile strength decreased and Young's modulus increased with starch concentration, but percent elongations remained similar to controls regardless of preparation method or starch content. Microscopy showed particulate starch distribution in films made with rapidly cooled starch-palmitic acid particles but smooth, diffuse starch staining with acidified sodium palmitate complexes. The mild effects on tensile properties suggest that submicron starch particles prepared from amylose-palmitic acid complexes provide a useful, commercially viable approach for PVOH film modification.

  12. [Usefulness of branched-chain amino acid (BCAA)-enriched nutrient mixture for nutritional treatment undergoing endoscopic treatment for esophageal varices].

    PubMed

    Shibata, Naozumi; Matsui, Hidetaka; Takeshita, Eiji; Yokota, Tomoyuki; Higaki, Naoyuki; Murakami, Hidehiro; Ikeda, Yoshiou; Minami, Hisaka; Matsuura, Bunzo; Onji, Morikazu

    2005-07-01

    We investigated the alteration of nutritional status in 144 patients who were treated for the first time with endoscopic sclerotherapy or endoscopic variceal ligation during their therapies. The serum levels of albumin, cholinesterase and total cholesterol were compared before and after treatment. The serum level of cholinesterase declined significantly. To investigate the impact of aging on the changes of nutritional status we divided all patients into two groups: (1) under 65 years, and (2) over 65 years. The decline of serum albumin of elderly patients (n=65) was significantly greater than that of younger patients (n=79). A branched-chain amino acid (BCAA)-enriched nutrient mixture for nutritional treatment significantly suppressed the decline of serum albumin in elderly patients. Nutritional treatment with a BCAA-enriched nutrient mixture should be considered during endoscopic therapy for esophageal varices, especially in elderly patients.

  13. STABILITY OF MFI ZEOLITE-FILLED PDMS MEMBRANES DURING PERVAPORATIVE ETHANOL RECOVERY FROM AQUEOUS MIXTURES CONTAINING ACETIC ACID

    EPA Science Inventory

    Pervaporation is a potential process for recovering bioethanol produced from biomass fermentation. Fermentation broths contain ethanol, water, and a variety of other compounds, often including carboxylic acids. The effects of acetic acid on long-term pervaporation of aqueous et...

  14. Multivalent ion-DNA interaction: Neutron scattering estimates of polyamine distribution

    NASA Astrophysics Data System (ADS)

    Zakharova, S. S.; Egelhaaf, S. U.; Bhuiyan, L. B.; Outhwaite, C. W.; Bratko, D.; van der Maarel, J. R. C.

    1999-12-01

    The partial structure factors pertaining to DNA-DNA, DNA-polyamine, and polyamine-polyamine density correlations in DNA fragment (contour length 54 nm) solutions have been measured with small angle neutron scattering and contrast matching in water. The effect of the polyamines putrescine and spermidine on the DNA molecular structure is gauged from the limiting behavior of the DNA-DNA partial structure factor at high values of momentum transfer. The double layer structure and the extent to which the polyamines can approach the DNA are derived from the DNA-polyamine and polyamine-polyamine partial structure factors. For this purpose, the structure factors are interpreted with the correlation functions derived from the classical Poisson-Boltzmann and the modified Poisson-Boltzmann equations and/or Monte Carlo simulation. For simple salt free DNA with tetramethylammonium or putrescine counterions, spatial fluctuations in the charge density are discussed in terms of the charge structure factor. The structural arrangement of putrescine and spermidine can be fully rationalized in terms of their valence. In the case of spermidine, it is necessary to include ionic correlation effects, but this could be accomplished by modeling the ligands as hard spheres. The polyamines have no detectable effect on the DNA molecular structure and are too large to penetrate the grooves to any significant extent. These results imply that DNA condensation in the presence of polyamines is largely governed by electrostatic interactions, rather than by the binding of the multivalent cation per se.

  15. Mixture Experiments

    SciTech Connect

    Piepel, Gregory F.

    2007-12-01

    A mixture experiment involves combining two or more components in various proportions or amounts and then measuring one or more responses for the resulting end products. Other factors that affect the response(s), such as process variables and/or the total amount of the mixture, may also be studied in the experiment. A mixture experiment design specifies the combinations of mixture components and other experimental factors (if any) to be studied and the response variable(s) to be measured. Mixture experiment data analyses are then used to achieve the desired goals, which may include (i) understanding the effects of components and other factors on the response(s), (ii) identifying components and other factors with significant and nonsignificant effects on the response(s), (iii) developing models for predicting the response(s) as functions of the mixture components and any other factors, and (iv) developing end-products with desired values and uncertainties of the response(s). Given a mixture experiment problem, a practitioner must consider the possible approaches for designing the experiment and analyzing the data, and then select the approach best suited to the problem. Eight possible approaches include 1) component proportions, 2) mathematically independent variables, 3) slack variable, 4) mixture amount, 5) component amounts, 6) mixture process variable, 7) mixture of mixtures, and 8) multi-factor mixture. The article provides an overview of the mixture experiment designs, models, and data analyses for these approaches.

  16. Antizyme (AZ) regulates intestinal cell growth independently of polyamines

    PubMed Central

    Ray, Ramesh M.; Bhattacharya, Sujoy; Bavaria, Mitul N.; Viar, Mary Jane; Johnson, Leonard R.

    2014-01-01

    Since antizyme (AZ) is known to inhibit cell proliferation and to increase apoptosis, the question arises as to whether these effects occur independently of polyamines. Intestinal epithelial cells (IEC-6) were grown in control medium and medium containing 5mM difluoromethylornithine (DFMO) to inhibit ODC, DFMO + 5μM spermidine (SPD), DFMO+ 5μM spermine (SPM), or DFMO+ 10 μM putrescine (PUT) for 4 days and various parameters of growth were measured along with AZ levels. Cell counts were significantly decreased and mean doubling times were significantly increased by DFMO. Putrescine restored growth in the presence of DFMO. However, both SPD and SPM when added with DFMO caused a much greater inhibition of growth than did DFMO alone, and both of these polyamines caused a dramatic increase in AZ. The addition of SPD or SPM to media containing DFMO + PUT significantly inhibited growth and caused a significant increase in AZ. IEC-6 cells transfected with AZ-siRNA grew more than twice as rapidly as either control cells or those incubated with DFMO, indicating that removal of AZ increases growth in cells in which polyamine synthesis is inhibited as well as in control cells. In a separate experiment the addition of SPD increased AZ levels and inhibited growth of cells incubated with DFMO by 50%. The addition of 10 mM asparagine (ASN) prevented the increase in AZ and restored growth to control levels. These results show that cell growth in the presence or absence of ODC activity and in the presence or absence of polyamines depends only on the levels of AZ. Therefore, the effects of AZ on cell growth are independent of polyamines. PMID:24930035

  17. Mixture of polysaccharide and nucleic acid extracted from Bacillus Calmette-Guerin (BCG) enhances immune response of infectious bursal disease virus vaccine in chickens.

    PubMed

    Wang, X B; Liu, Z J; Lv, Y J; Long, Y; Bao, E D

    2016-05-12

    In this study, the immune response induced by a mixture of polysaccharide and nucleic acid extracted from Bacillus Calmette-Guerin (BCG) was evaluated in chickens inoculated with infectious bursal disease virus (IBDV) vaccine. After the mixture was injected intramuscularly at a dose of 0.075, 0.15 or 0.3 mg·kg(-1)·day(-1) for 3 days, the 14-day-old chickens were inoculated with the attenuated IBDV vaccine via intranasal and ocular routes. The relative weight of bursa of Fabricius (BF) and thymus, the serum IBD antibody titer, the CD4+/CD8+ ratio, and the concentrations of IFN-γ, IL-2 and IL-6 in peripheral blood were investigated on days 5, 15 and 25. The IBD antibody titer in BCG-treated groups was higher than in the negative control and only IBD-vaccinated chickens, indicating that the mixture of BCG can significantly enhance chicken humoral response. CD4+/CD8+ and the secretions of IFN-γ, IL-2 and IL-6 were also clearly increased compared with that in the negative control and IBD-vaccinated chickens, indicating that the mixture can also enhance the cell-mediated immune response. The results also showed that the relative weights of BF and thymus increased after chickens were inoculated with BCG, indicating that the BCG mixture can clearly enhance the immunity of IBD-vaccine and can be expected to be viewed as a candidate for a new type of immune adjuvant.

  18. Modelling interactions of acid-base balance and respiratory status in the toxicity of metal mixtures in the American oyster Crassostrea virginica.

    PubMed

    Macey, Brett M; Jenny, Matthew J; Williams, Heidi R; Thibodeaux, Lindy K; Beal, Marion; Almeida, Jonas S; Cunningham, Charles; Mancia, Annalaura; Warr, Gregory W; Burge, Erin J; Holland, A Fred; Gross, Paul S; Hikima, Sonomi; Burnett, Karen G; Burnett, Louis; Chapman, Robert W

    2010-03-01

    Heavy metals, such as copper, zinc and cadmium, represent some of the most common and serious pollutants in coastal estuaries. In the present study, we used a combination of linear and artificial neural network (ANN) modelling to detect and explore interactions among low-dose mixtures of these heavy metals and their impacts on fundamental physiological processes in tissues of the Eastern oyster, Crassostrea virginica. Animals were exposed to Cd (0.001-0.400 microM), Zn (0.001-3.059 microM) or Cu (0.002-0.787 microM), either alone or in combination for 1 to 27 days. We measured indicators of acid-base balance (hemolymph pH and total CO(2)), gas exchange (Po(2)), immunocompetence (total hemocyte counts, numbers of invasive bacteria), antioxidant status (glutathione, GSH), oxidative damage (lipid peroxidation; LPx), and metal accumulation in the gill and the hepatopancreas. Linear analysis showed that oxidative membrane damage from tissue accumulation of environmental metals was correlated with impaired acid-base balance in oysters. ANN analysis revealed interactions of metals with hemolymph acid-base chemistry in predicting oxidative damage that were not evident from linear analyses. These results highlight the usefulness of machine learning approaches, such as ANNs, for improving our ability to recognize and understand the effects of sub-acute exposure to contaminant mixtures.

  19. Effects of prenatal exposure to 2,4-D/2,4,5-T mixture on postnatal changes in rat brain glutamate, GABA protein, and nucleic acid levels

    SciTech Connect

    Mohammad, F.K.; Omer, V.E.V.

    1988-02-01

    The opportunity of maternal exposure to various chemicals in the work place and the general environments have increased, and the fetus and neonate may be at greater risk than the adult. However, the embryotoxic and teratogenic effects of the chlorinated phenoxy herbicides 2,4-dichlorophenoxyacetic acid (2,4-D) and 2,4,5-trichlorophenoxyacetic acid (2,4,5-T), the main chemicals in Agent Orange, are well documented only in laboratory animals. The brain of the developing fetus is vulnerable to the toxic effects of the phenoxy herbicides which readily cross the placental barrier and distribute into fetal tissues, including brain. Although the neurochemical basis for the behavioral teratogenicity of the phenoxy herbicides is not know, it was recently reported that non-teratogenic doses of a 1:1 mixture of 2,4-D and 2,4,5-T delayed the ontogeny of dopamine and serotonin in the brain of the developing rate. This communication provides further descriptive information about the ontogeny of rat brain nucleic acid, protein, glutamate and ..gamma..-aminobutyrate (GABA) following in utero exposure to non-teratogenic levels of a 1:1 mixture of 2,4-D/2,4,5-T.

  20. The source of inoculum plays a defining role in the development of MEC microbial consortia fed with acetic and propionic acid mixtures.

    PubMed

    Ruiz, Vianey; Ilhan, Zehra Esra; Kang, Dae-Wook; Krajmalnik-Brown, Rosa; Buitrón, Germán

    2014-07-20

    Microbial electrolysis cells (MECs) can be used as a downstream process to dark fermentation to further capture electron in volatile fatty acids that remain after fermentation, improving this way the viability of the overall process. Acetic and propionic acid are common products of dark fermentation. The main objective of this work was to investigate the effect of different initial concentrations of a mixture of acetic and propionic acids on MECs microbial ecology and hydrogen production performance. To link microbial structure and function, we characterized the anode respiring biofilm communities using pyrosequencing and quantitative-PCR. The best hydrogen production rates (265mL/d/Lreactor) were obtained in the first block of experiments by MEC fed with 1500mg/L acetic acid and 250mg/L propionic acid. This reactor presents in the anode biofilm an even distribution of Proteobacteria, Firmicutes and Bacteroidetes and Arcobacter was the dominant genera. The above fact also correlated to the highest electron load among all the reactors. It was evidenced that although defined acetic and propionic acid concentrations fed affected the structure of the microbial consortia that developed at the anode, the initial inoculum played a major role in the development of MEC microbial consortia.

  1. [A DNA study of rat liver oligonucleosomes enriched by transcriptionally active genes during induction due to the administration of an amino acid mixture].

    PubMed

    Vardevanian, P O; Davtian, A M; Tiratsuian, S G; Vardevanian, A O

    1990-01-01

    A highly active fraction of rat liver oligonucleosome DNA has been isolated and studied by means of thermal denaturation after induction by amino acid mixture or hydrocortisone. A considerable redistribution of DNA content has been shown in sucrose gradient fractions during these forms of induction. The changes are revealed in melting temperature, differential melting profile of DNA, isolated from actively transcribed chromatine fractions. Analysis of melting profiles shows changes of GC content of oligonucleosome DNA, suggesting that there are differences in activation during two studied forms of induction.

  2. Rapid determination of the equivalence volume in potentiometric acid-base titrations to a preset pH-II Standardizing a solution of a strong base, graphic location of equivalence volume, determination of stability constants of acids and titration of a mixture of two weak acids.

    PubMed

    Ivaska, A

    1974-06-01

    A newly proposed method of titrating weak acids with strong bases is applied to standardize a solution of a strong base, to graphic determination of equivalence volume of acetic acid with an error of 0.2%, to calculate the stability constants of hydroxylammonium ion, boric acid and hydrogen ascorbate ion and to analyse a mixture of acetic acid and ammonium ion with an error of 0.2-0.7%.

  3. Effects of agmatine on secretion of interferon tau and catecholamines and expression of genes related to production of polyamines by ovine trophectoderm cells.

    PubMed

    Lenis, Yasser Y; Wang, Xiaoqiu; Tang, Wanjin; Wu, Guoyao; Bazer, Fuller W

    2016-10-01

    Embryonic survival requires histotrophic nutrition, including molecules secreted or transported into the uterine lumen by uterine epithelia. L-Arginine (Arg) is a common substrate for synthesis of nitric oxide, ornithine, proline, glutamate, creatinine, urea, polyamines and agmatine. Agmatine (Agm) is a product of arginine decarboxylation and it is a substrate for agmatinase for synthesis of putrescine and other polyamines in the ovine conceptus. Polyamines are essential for conceptus development. Therefore, this study compared effects of Arg and Agm on the behavior of ovine trophectoderm (oTr1) cells cultured in vitro. Arg, but not Agm, increased proliferation and migration of oTr1 cells, but neither Arg nor Agm affected cell adhesion. The total amount of IFNT in culture medium of oTr1 cells was increased by Arg, but Agm increased the IFNT production per oTr1 cell. Arg and Agm plus Arg decreased secretion of dopamine and norepinephrine by oTr1 cells. Agm upregulates expression of mRNAs SLC7A1, agmatinase and OAZ2 while the combination of Arg and Agm decreased expression of mRNAs for ODC1, SLC7A1, OAZ1 and OAZ3 by oTr1 cells. Although Agm does not stimulate proliferation, migration or adhesion of oTr1 cells or their secretion of catecholamines, Agm did increase transcription of SLC7A1, agmatinase and OAZ2 genes which would increase the capacity of oTr1 cells to produce polyamines. Collectively, our findings suggest a role for Arg and Agm in the regulation of transport of basic amino acids (including Arg), polyamine synthesis, and secretion of catecholamines by oTr1 cells.

  4. Gamma-radiation-induced grafting of binary mixture of methacrylic acid and 4-vinyl pyridine onto Teflon-FEP film as an effective polar membrane for separation processes

    NASA Astrophysics Data System (ADS)

    Kaur, Inderjeet; Rattan, Sunita; Chauhan, Sandeep; Gupta, Nitika

    2010-05-01

    Ionic bifunctional membranes have been synthesized by grafting binary mixture of methacrylic acid (MAAc) and 4-vinyl pyridine (4-VP) onto Teflon-FEP film by pre-irradiation method. Optimum conditions pertaining to maximum percentage of grafting were evaluated as a function of different reaction parameters. Maximum percentage of grafting of binary mixture (MAAc-co-4-VP) (71.29%) was obtained at an optimum total dose of 54.48 kGy and the total concentration was 9.49 mol/L ([4-VP] = 0.07 mol/L and [MAAc ] = 9.42 mol/L) in 5 ml of water. The effect of alcohols as additives to the reaction medium on percent grafting of the binary mixture has also been studied. The membranes were characterized by FTIR spectroscopy, scanning electron microscopy and thermogravimetric analysis. Swelling studies of the membranes were performed in different solvents such as water, benzene, carbon tetrachloride and dimethyl formamide (DMF). Maximum swelling was observed in DMF with minimum swelling in benzene. Metal ion (Cu 2+, Ni 2+ and Fe 2+) uptake studies show better affinity for Fe 2+ ions. Conductance measurements in different aqueous salt solution showed that these membranes have affinity for Na +/K + ions and Cl - ions and hence can be used in desalination/separation processes for the separation of both type of cationic and anionic ions.

  5. Biochemical passive reactors for treatment of acid mine drainage: Effect of hydraulic retention time on changes in efficiency, composition of reactive mixture, and microbial activity.

    PubMed

    Vasquez, Yaneth; Escobar, Maria C; Neculita, Carmen M; Arbeli, Ziv; Roldan, Fabio

    2016-06-01

    Biochemical passive treatment represents a promising option for the remediation of acid mine drainage. This study determined the effect of three hydraulic retention times (1, 2, and 4 days) on changes in system efficiency, reactive mixture, and microbial activity in bioreactors under upward flow conditions. Bioreactors were sacrificed in the weeks 8, 17 and 36, and the reactive mixture was sampled at the bottom, middle, and top layers. Physicochemical analyses were performed on reactive mixture post-treatment and correlated with sulfate-reducing bacteria and cellulolytic and dehydrogenase activity. All hydraulic retention times were efficient at increasing pH and alkalinity and removing sulfate (>60%) and metals (85-99% for Fe(2+) and 70-100% for Zn(2+)), except for Mn(2+). The longest hydraulic retention time (4 days) increased residual sulfides, deteriorated the quality of treated effluent and negatively impacted sulfate-reducing bacteria. Shortest hydraulic retention time (1 day) washed out biomass and increased input of dissolved oxygen in the reactors, leading to higher redox potential and decreasing metal removal efficiency. Concentrations of iron, zinc and metal sulfides were high in the bottom layer, especially with 2 day of hydraulic retention time. Sulfate-reducing bacteria, cellulolytic and dehydrogenase activity were higher in the middle layer at 4 days of hydraulic retention time. Hydraulic retention time had a strong influence on overall performance of passive reactors.

  6. Methanothermal treatment of carbonated mixtures of PbSO4 and PbO2 to synthesize α-PbO for lead acid batteries

    NASA Astrophysics Data System (ADS)

    Gao, Pengran; Lv, Weixin; Zhang, Rui; Liu, Yi; Li, Guanghua; Bu, Xianfu; Lei, Lixu

    2014-02-01

    We have developed a novel route to make new batteries from spent ones, in which we obtain and regenerate the active materials of positive electrode and negative electrode respectively. For the spent lead acid batteries, the positive electrode active materials contain both PbSO4 and PbO2. To make full use of them, we have to investigate the treatment of the mixtures rather than only PbO2, which we have reported previously. Here we report our investigation on three mixtures of PbSO4 and PbO2 in different mole ratios, as well as the electrode materials directly from the spent batteries. The mixtures are firstly desulphated, and then solvothermally processed in methanol at 140 °C for 24 h. The as-obtained solids contain both PbO·PbCO3 and PbCO3, which have been calcined to form α-PbO. The α-PbO powders are similar irregular particles and highly electrochemically active, which discharge around 170 mAh g-1 at 5 mA g-1, 80 mAh g-1 at 200 mA g-1 and 60 mAh g-1 at 400 mA g-1 with excellent cyclic stability in 50 cycles.

  7. Synthesis of some 1,8-dioxoacridine carboxylic acid derivatives and the determination of their ionization constants in ethanol-water mixtures

    NASA Astrophysics Data System (ADS)

    Saygılı, Rukiye; Ulus, Ramazan; Yeşildağ, İbrahim; Kübra İnal, E.; Kaya, Muharrem; Murat Kalfa, O.; Zeybek, Bülent

    2015-03-01

    Four novel compounds of 1,8-dioxoacridine carboxylic acid derivatives (4-(3,3,6,6-tetramethyl-1,8-dioxo-9-phenyl-1,2,3,4,5,6,7,8-octahydroacridin-10(9H)-yl)benzoic acid, 4-(9-(4-cyanophenyl)-3,3,6,6-tetramethyl-1,8-dioxo-1,2,3,4,5,6,7,8-octahydroacridin-10(9H)-yl)benzoic acid, 4-(9-(4-hydroxyphenyl)-3,3,6,6-tetramethyl-1,8-dioxo-1,2,3,4,5,6,7,8-octahydroacridin-10(9H)-yl)benzoic acid, 4-(9-(2,4-dichlorophenyl)-3,3,6,6-tetramethyl-1,8-dioxo-1,2,3,4,5,6,7,8-octahydroacridin-10(9H)-yl)benzoic acid) were prepared by the reaction of the 4-substitute benzaldehyde (hydrogen, hydroxyl, cyano, and 2,4-dichloro), 4-aminobenzoic acid, and 5,5-dimethylcyclohexane-1,3-dione in the presence of p-dodecylbenzenesulfonic acid. They were characterized by using FT-IR, 1H-NMR, 13C-NMR, GC-MS spectroscopic techniques. The stoichiometric ionization constants of these compounds were determined in ethanol-water mixtures of 50%, 60% and 70% ethanol (v/v) by potentiometric titration method and the ionization constants were calculated with three different ways. The effects of solvent composition and substituent groups on ionization constants of 1,8-dioxoacridine carboxylic acids were also discussed.

  8. Effect of different levels of an ascorbic acid and tea mixture on nonheme iron absorption from a typical Tunisian meal fed to healthy rats.

    PubMed

    Hamdauoui, M; Doghri, T; Tritar, B

    1995-01-01

    The aim of our study was to evaluate the bioavailability of iron from a typical Tunisian meal 'couscous' provided to healthy rats with or without appropriate mixtures of tea plus ascorbic acid and to search for the optimal amount of ascorbic acid able to overcome the inhibitory effect of tea prepared under realistic Tunisian circumstances. Our findings show that a tea decoction (100 mg/ml) reduced nonheme iron absorption from couscous by 50% (16.5 vs. 33.1%; p < 0.01). In contrast, administration of 20 mg ascorbic acid increased nonheme iron absorption from couscous by more than 100% (66.8 vs. 33.1%; p < 0.001). Administration of ascorbic acid (20 mg) in a tea decoction (100 mg/ml) completely counteracted the inhibiting effect of tea and significantly improved the nonheme iron absorption from couscous (34 vs. 33% in the control group; NS). The same effect was shown when 10 mg ascorbic acid was added to the tea decoction; however, 5 mg ascorbic acid was not able to overcome the inhibitory effect of tea on nonheme iron absorption from couscous (33.1 vs. 19.4%; p < 0.01). Our findings demonstrate that a molar ratio of ascorbic acid and tea equal or superior to 0.25 or 0.50 is necessary to overcome the inhibitory effect in rats of tea prepared under Tunisian circumstances. In relation to human nutrition, for Tunisians who regularly drink tea, we suggest a much greater amount of ascorbic acid than that normally recommended for normal subjects.

  9. Role of Polyamine Oxidase (PAOH1/SMO) in Human Breast Cancer

    DTIC Science & Technology

    2005-04-01

    activity in human breast cancer cell lines. Pledgie A, Huang Y, Hacker A, Woster PM, Casero RA, and Davidson NE. Proc AACR. Page 1224, 2004...polyamine metabolism. Biochem J. 376: 1-14, 2003. 2. Huang Y, Pledgie A, Casero RA, and Davidson NE. Molecular mechanisms of polyamine analogs in cancer...Devereux W, Hacker A, Frydman B, Woster PM, and Casero RA. Properties of purified recombinant human polyamine oxidase, PAOh1/SMO. Biochem Biophys Res

  10. Nitrogen Sparing Induced by a Mixture of Essential Amino Acids Given Chiefly as Their Keto-Analogues during Prolonged Starvation in Obese Subjects

    PubMed Central

    Sapir, Daniel G.; Owen, Oliver E.; Pozefsky, Thomas; Walser, Mackenzie

    1974-01-01

    11 normal obese subjects were fasted for 33 days. In five, who served as controls, urine urea nitrogen excretion remained constant for 2 wk thereafter. The other six were given seven daily infusions containing 6-8 mmol each of the α-keto-analogues of valine, leucine, isoleucine, phenylalanine, and methionine (as sodium salts) plus 3-4 mmol each of the remaining essential amino acids (lysine, threonine, tryptophan, and histidine). Rapid amination of the infused ketoacids occurred, as indicated by significant increases in plasma concentrations of valine, leucine, isoleucine, alloisoleucine, phenylalanine, and methionine. Glutamine, glycine, serine, glutamate, and taurine fell significantly. Blood glucose, ketone bodies, plasma free fatty acids, and serum immunoreactive insulin concentrations were unaltered. Urine urea nitrogen fell from 1.46 to 0.89 g/day on the last day of infusions; 5 days later it was still lower (0.63 g/day) and in two subjects studied for 9 and 17 days postinfusion it remained below preinfusion control values. Urine ammonia, creatinine, and uric acid were unaltered. Nitrogen balance became less negative during and after infusions. The results indicate that this mixture of essential amino acids and their keto-analogues facilitates nitrogen sparing during prolonged starvation, in part by conversion of the ketoacids to amino acids and in part by altering mechanisms of nitrogen conservation. The latter effect persists after the ketoacids are metabolized. PMID:4430727

  11. Developmental toxicity of mixtures: the water disinfection by-products dichloro-, dibromo- and bromochloro acetic acid in rat embryo culture

    EPA Science Inventory

    The chlorination of drinking water results in production of numerous disinfection by-products (DBPs). One of the important classes of DBPs is the haloacetic acids. We have previously shown that the haloacetic acids (HAs), dichloro (DCA), dibromo (DBA) and bromochloro (BCA) acetic...

  12. Polyamine formation by arginine decarboxylase as a transducer of hormonal, environmental and stress stimuli in higher plants

    NASA Technical Reports Server (NTRS)

    Galston, A. W.; Flores, H. E.; Kaur-Sawhney, R.

    1982-01-01

    Recent evidence implicates polyamines including putrescine in the regulation of such diverse plant processes as cell division, embryogenesis and senescence. We find that the enzyme arginine decarboxylase, which controls the rate of putrescine formation in some plant systems, is activated by light acting through P(r) phytochrome as a receptor, by the plant hormone gibberellic acid, by osmotic shock and by other stress stimuli. We therefore propose arginine decarboxylase as a possible transducer of the various initially received tropistic stimuli in plants. The putrescine formed could act by affecting cytoskeletal components.

  13. Simplified dietary acute tryptophan depletion: effects of a novel amino acid mixture on the neurochemistry of C57BL/6J mice

    PubMed Central

    Sánchez, Cristina L.; Van Swearingen, Amanda E. D.; Arrant, Andrew E.; Biskup, Caroline S.; Kuhn, Cynthia M.; Zepf, Florian D.

    2015-01-01

    Background Diet and nutrition can impact on the biological processes underpinning neuropsychiatric disorders. Amino acid (AA) mixtures lacking a specific neurotransmitter precursor can change the levels of brain serotonin (5-HT) or dopamine (DA) in the central nervous system. The availability of these substances within the brain is determined by the blood–brain barrier (BBB) that restricts the access of peripheral AA into the brain. AA mixtures lacking tryptophan (TRP) compete with endogenous TRP for uptake into the brain across the BBB, which in turn leads to a decrease in central nervous 5-HT synthesis. Objective The present study compared the effects of a simplified acute tryptophan depletion (SATD) mixture in mice on blood and brain serotonergic and dopaminergic metabolites to those of a commonly used acute tryptophan depletion mixture (ATD Moja-De) and its TRP-balanced control (BAL). Design The SATD formula is composed of only three large neutral AAs: phenylalanine (PHE), leucine (LEU), and isoleucine (ILE). BAL, ATD Moja-De, or SATD formulas were delivered to adult male C57BL/6J mice by gavage. TRP, monoamines, and their metabolites were quantified in blood and brain regions (hippocampus, frontal cortex, amygdala, caudate putamen, and nucleus accumbens). Results Both ATD Moja-De and SATD significantly decreased levels of serum and brain TRP, as well as brain 5-HIAA and 5-HT compared with BAL. SATD reduced HVA levels in caudate but did not alter total DA levels or DOPAC. SATD decreased TRP and serotonergic metabolites comparably to ATD Moja-De administration. Conclusion A simplified and more palatable combination of AAs can manipulate serotonergic function and might be useful to reveal underlying monoamine-related mechanisms contributing to different neuropsychiatric disorders. PMID:26278978

  14. Abnormal urinary excretion of polyamines in HHH syndrome (hyperornithinemia associated with hyperammonemia and homocitrullinuria).

    PubMed

    Shimizu, H; Maekawa, K; Eto, Y

    1990-01-01

    The HHH syndrome (hyperornithinemia associated with hyperammonemia and homocitrullinuria) is characterized by a very rare genetic defect of ornithine transport in mitochondrial membrane. We first demonstrated that a patient with HHH syndrome excreted about 6 times higher amount of polyamines in urine than the control when supplemented with high protein diets and ornithine loading. Each urinary polyamine fraction measured by HPLC method in HHH syndrome appears to be increased, as compared with those of the control. These data suggest that increased urinary excretion of polyamines in this syndrome is closely related to overflowing of plasma polyamine due to an ornithine transport defect in the mitochondrial membrane.

  15. Alterations in repair of alkylating agent-induced DNA damage in polyamine-depleted human cells.

    PubMed

    Snyder, R D; Bhatt, S

    1993-08-16

    Treatment of HeLa cells with the polyamine biosynthesis inhibitors difluoromethylornithine (DFMO) and/or methylglyoxal bis(guanylhydrazone) (MGBG) results in marked depression in levels of the cellular polyamines putrescine, spermidine and spermine. Cells in this polyamine-depleted state exhibited increased sensitivity to monofunctional alkylating agents, manifested as decreased cloning ability and retardation of the DNA excision repair process. DFMO treatment did not alter the initial level of interaction of radiolabeled alkylating agent with cellular DNA, but combined treatment with DFMO and MGBG reduced covalent binding, probably through effects on cell cycling. Polyamine supplementation had no effects on initial yield of DNA single-strand breaks in drug-treated cells. The repair defect appeared similar to that observed previously in polyamine-depleted cells following X-irradiation and UV irradiation, namely retarded sealing of DNA strand breaks. It was not possible to reverse the effects of these inhibitors by short periods of polyamine loading, despite the fact that all three polyamines could be restored to near-normal levels. These findings provide the first demonstration of altered response of polyamine-depleted cells to monofunctional alkylating agents and contribute to our understanding of altered responses of polyamine-depleted cancer cells to a variety of DNA-reactive chemotherapeutic drugs.

  16. Conjugation of biogenic and synthetic polyamines with serum proteins: A comprehensive review.

    PubMed

    Chanphai, P; Thomas, T J; Tajmir-Riahi, H A

    2016-11-01

    We have reviewed the conjugation of biogenic polyamines spermine (spm), spermidine (spmd) and synthetic polyamines 3,7,11,15-tetrazaheptadecane.4HCl (BE-333) and 3,7,11,15,19-pentazahenicosane.5HCl (BE-3333) with human serum albumin (HSA), bovine serum albumin (BSA) and milk beta-lactoglobulin (b-LG) in aqueous solution at physiological pH. The results of multiple spectroscopic methods and molecular modeling were analysed here and correlations between polyamine binding mode and protein structural changes were estabilished. Polyamine-protein bindings are mainly via hydrophilic and H-bonding contacts. BSA forms more stable conjugates than HSA and b-LG. Biogenic polyamines form more stable complexes than synthetic polyamines except in the case of b-LG, where the protein shows more hydrophobic character than HSA and BSA. The loading efficacies were 40-52%. Modeling showed the presence of several H-bonding systems, which stabilized polyamine-protein conjugates. Polyamine conjugation induced major alterations of serum protein conformations. The potential application of serum proteins in delivery of polyamines is evaluated here.

  17. Polyamines control of cation transport across plant membranes: implications for ion homeostasis and abiotic stress signaling

    PubMed Central

    Pottosin, Igor; Shabala, Sergey

    2014-01-01

    Polyamines are unique polycationic metabolites, controlling a variety of vital functions in plants, including growth and stress responses. Over the last two decades a bulk of data was accumulated providing explicit evidence that polyamines play an essential role in regulating plant membrane transport. The most straightforward example is a blockage of the two major vacuolar cation channels, namely slow (SV) and fast (FV) activating ones, by the micromolar concentrations of polyamines. This effect is direct and fully reversible, with a potency descending in a sequence Spm4+ > Spd3+ > Put2+. On the contrary, effects of polyamines on the plasma membrane (PM) cation and K+-selective channels are hardly dependent on polyamine species, display a relatively low affinity, and are likely to be indirect. Polyamines also affect vacuolar and PM H+ pumps and Ca2+ pump of the PM. On the other hand, catabolization of polyamines generates H2O2 and other reactive oxygen species (ROS), including hydroxyl radicals. Export of polyamines to the apoplast and their oxidation there by available amine oxidases results in the induction of a novel ion conductance and confers Ca2+ influx across the PM. This mechanism, initially established for plant responses to pathogen attack (including a hypersensitive response), has been recently shown to mediate plant responses to a variety of abiotic stresses. In this review we summarize the effects of polyamines and their catabolites on cation transport in plants and discuss the implications of these effects for ion homeostasis, signaling, and plant adaptive responses to environment. PMID:24795739

  18. Quantitative analysis of binary polymorphs mixtures of fusidic acid by diffuse reflectance FTIR spectroscopy, diffuse reflectance FT-NIR spectroscopy, Raman spectroscopy and multivariate calibration.

    PubMed

    Guo, Canyong; Luo, Xuefang; Zhou, Xiaohua; Shi, Beijia; Wang, Juanjuan; Zhao, Jinqi; Zhang, Xiaoxia

    2017-03-10

    Vibrational spectroscopic techniques such as infrared, near-infrared and Raman spectroscopy have become popular in detecting and quantifying polymorphism of pharmaceutics since they are fast and non-destructive. This study assessed the ability of three vibrational spectroscopy combined with multivariate analysis to quantify a low-content undesired polymorph within a binary polymorphic mixture. Partial least squares (PLS) regression and support vector machine (SVM) regression were employed to build quantitative models. Fusidic acid, a steroidal antibiotic, was used as the model compound. It was found that PLS regression performed slightly better than SVM regression in all the three spectroscopic techniques. Root mean square errors of prediction (RMSEP) were ranging from 0.48% to 1.17% for diffuse reflectance FTIR spectroscopy and 1.60-1.93% for diffuse reflectance FT-NIR spectroscopy and 1.62-2.31% for Raman spectroscopy. The results indicate that diffuse reflectance FTIR spectroscopy offers significant advantages in providing accurate measurement of polymorphic content in the fusidic acid binary mixtures, while Raman spectroscopy is the least accurate technique for quantitative analysis of polymorphs.

  19. Phase behavior and formation of o/w nano-emulsion in vegetable oil/ mixture of polyglycerol polyricinoleate and polyglycerin fatty acid ester/water systems.

    PubMed

    Wakisaka, Satoshi; Nakanishi, Masami; Gohtani, Shoichi

    2014-01-01

    It is reported that mixing polyglycerol polyricinoleate (PGPR) and polyglycerol laurilester has a great emulsifying capacity, and consequently fine oil-in-water (o/w) emulsions can be formed. However, the role of PGPR is not clear. The objective of this research is to investigate the phase behavior of vegetable oil/mixture of PGPR and polyglycerol fatty acid ester/water systems, and to clarify the role of PGPR in making a fine emulsion. Phase diagrams were constructed to elucidate the optimal process for preparing fine emulsions. In all the systems examined in this study, the phases, including the liquid crystal phase (L(c)) and sponge phase (L(3)), spread widely in the phase diagrams. We examined droplet size of the emulsions prepared from each phase and found that o/w nano-emulsions with droplet sizes as small as 50 nm were formed by emulsifying either from a single L(3) phase or a two-phase region, L(c) + L(3). These results indicate that a sponge phase L(3) or liquid crystal phase L(c) or both is necessary to form an o/w nano-emulsion whose average droplet diameter is less than 50 nm for PGPR and polyglycerin fatty acid ester mixtures used as surfactant.

  20. Changes in the contents and profiles of selected phenolics, soyasapogenols, tocopherols, and amino acids during soybean-rice mixture cooking: Electric rice cooker vs electric pressure rice cooker.

    PubMed

    Kim, Seung-Hyun; Yu, Bo-Ra; Chung, Ill-Min

    2015-06-01

    This study investigated the changes in the contents and profiles of 35 phenolics (including 12 isoflavones), four tocopherols, two soyasapogenols and 20 amino acids when soybean and rice were cooked together (soybean-rice mixture) using either an electric rice cooker (ERC) or an electric pressure rice cooker (EPRC). The contents of the 35 selected phenolics in soybean decreased by 12% and 8% upon cooking by ERC and EPRC, respectively, and their profiles were different from that prior to cooking (P<0.05). Total tocopherol content of soybeans decreased by 7% after cooking in an ERC, but increased by 3% in soybeans cooked by EPRC. Total soyasapogenol content in soybeans cooked by ERC and EPRC decreased by 15% and 6%, respectively. Lastly, the total amino acid content of soybeans increased by 41% and 10% after cooking by ERC and EPRC, respectively. This study extends our knowledge about the effects of heat and pressure on the contents and profiles of bioactive compounds during soybean-rice mixture cooking. These results may be useful for improving the quality of bioactive compounds in soybean and rice depending on cooking conditions.

  1. Maternal and cord blood LC-HRMS metabolomics reveal alterations in energy and polyamine metabolism, and oxidative stress in very-low birth weight infants.

    PubMed

    Alexandre-Gouabau, Marie-Cécile; Courant, Frédérique; Moyon, Thomas; Küster, Alice; Le Gall, Gwénaëlle; Tea, Illa; Antignac, Jean-Philippe; Darmaun, Dominique

    2013-06-07

    To assess the global effect of preterm birth on fetal metabolism and maternal-fetal nutrient transfer, we used a mass spectrometric-based chemical phenotyping approach on cord blood obtained at the time of birth. We sampled umbilical venous, umbilical arterial, and maternal blood from mothers delivering very-low birth weight (VLBW, with a median gestational age and weight of 29 weeks, and 1210 g, respectively) premature or full-term (FT) neonates. In VLBW group, we observed a significant elevation in the levels and maternal-fetal gradients of butyryl-, isovaleryl-, hexanoyl- and octanoyl-carnitines, suggesting enhanced short- and medium chain fatty acid β-oxidation in human preterm feto-placental unit. The significant decrease in glutamine-glutamate in preterm arterial cord blood beside lower levels of amino acid precursors of Krebs cycle suggest increased glutamine utilization in the fast growing tissues of preterm fetus with a deregulation in placental glutamate-glutamine shuttling. Enhanced glutathione utilization is likely to account for the decrease in precursor amino acids (serine, betaine, glutamate and methionine) in arterial cord blood. An increase in both the circulating levels and maternal-fetal gradients of several polyamines in their acetylated form (diacetylspermine and acetylputrescine) suggests an enhanced polyamine metabolic cycling in extreme prematurity. Our metabolomics study allowed the identification of alterations in fetal energy, antioxidant defense, and polyamines and purines flux as a signature of premature birth.

  2. Method for regenerating magnetic polyamine-epichlorohydrin resin

    DOEpatents

    Kochen, R.L.; Navratil, J.D.

    1997-07-29

    Magnetic polymer resins capable of efficient removal of actinides and heavy metals from contaminated water are disclosed together with methods for making, using, and regenerating them. The resins comprise polyamine-epichlorohydrin resin beads with ferrites attached to the surfaces of the beads. Markedly improved water decontamination is demonstrated using these magnetic polymer resins of the invention in the presence of a magnetic field, as compared with water decontamination methods employing ordinary ion exchange resins or ferrites taken separately. 9 figs.

  3. Method for regenerating magnetic polyamine-epichlorohydrin resin

    DOEpatents

    Kochen, Robert L.; Navratil, James D.

    1997-07-29

    Magnetic polymer resins capable of efficient removal of actinides and heavy metals from contaminated water are disclosed together with methods for making, using, and regenerating them. The resins comprise polyamine-epichlorohydrin resin beads with ferrites attached to the surfaces of the beads. Markedly improved water decontamination is demonstrated using these magnetic polymer resins of the invention in the presence of a magnetic field, as compared with water decontamination methods employing ordinary ion exchange resins or ferrites taken separately.

  4. Polyamine depletion inhibits the autophagic response modulating Trypanosoma cruzi infectivity

    PubMed Central

    Vanrell, María C.; Cueto, Juan A.; Barclay, Jeremías J.; Carrillo, Carolina; Colombo, María I.; Gottlieb, Roberta A.; Romano, Patricia S.

    2013-01-01

    Autophagy is a cell process that in normal conditions serves to recycle cytoplasmic components and aged or damaged organelles. The autophagic pathway has been implicated in many physiological and pathological situations, even during the course of infection by intracellular pathogens. Many compounds are currently used to positively or negatively modulate the autophagic response. Recently it was demonstrated that the polyamine spermidine is a physiological inducer of autophagy in eukaryotic cells. We have previously shown that the etiological agent of Chagas disease, the protozoan parasite Trypanosoma cruzi, interacts with autophagic compartments during host cell invasion and that preactivation of autophagy significantly increases host cell colonization by this parasite. In the present report we have analyzed the effect of polyamine depletion on the autophagic response of the host cell and on T. cruzi infectivity. Our data showed that depleting intracellular polyamines by inhibiting the biosynthetic enzyme ornithine decarboxylase with difluoromethylornithine (DFMO) suppressed the induction of autophagy in response to starvation or rapamycin treatment in two cell lines. This effect was associated with a decrease in the levels of LC3 and ATG5, two proteins required for autophagosome formation. As a consequence of inhibiting host cell autophagy, DFMO impaired T. cruzi colonization, indicating that polyamines and autophagy facilitate parasite infection. Thus, our results point to DFMO as a novel autophagy inhibitor. While other autophagy inhibitors such as wortmannin and 3-methyladenine are nonspecific and potentially toxic, DFMO is an FDA-approved drug that may have value in limiting autophagy and the spread of the infection in Chagas disease and possibly other pathological settings. PMID:23697944

  5. Optimization of polyphenol extraction from red grape pomace using aqueous glycerol/tartaric acid mixtures and response surface methodology.

    PubMed

    Makris, Dimitris P; Passalidi, Vassiliki; Kallithraka, Stamatina; Mourtzinos, Ioannis

    2016-01-01

    Grape pomace is a food industry waste containing a high burden of antioxidant polyphenols and several methodologies have been developed for their efficient extraction. However, a sustainable and environmentally friendly process should involve recovery means composed of benign, non-toxic solvents, such as tartaric acid and glycerol, which are natural food constituents. In this line, this study examined the extraction of polyphenols using aqueous tartaric acid/glycerol solutions. The aim was to assess the role of acid and glycerol concentration in the extraction yield, employing a Box-Behnken experimental design and response surface methodology. The results showed that solutions containing only glycerol (20%, w/v) are more suitable for retrieving polyphenols, flavonoids, and pigments from grape pomace, while tartaric acid exerted a negative effect in this regard, when tested at concentrations up to 2% (w/v).

  6. Proboscis conditioning experiments with honeybees, Apis mellifera caucasica, with butyric acid and DEET mixture as conditioned and unconditioned stimuli.

    PubMed

    Abramson, Charles I; Giray, Tugrul; Mixson, T Andrew; Nolf, Sondra L; Wells, Harrington; Kence, Aykut; Kence, Meral

    2010-01-01

    Three experiments are described investigating whether olfactory repellents DEET and butyric acid can support the classical conditioning of proboscis extension in the honeybee, Apis mellifera caucasica (Hymenoptera: Apidae). In the first experiment DEET and butyric acid readily led to standard acquisition and extinction effects, which are comparable to the use of cinnamon as a conditioned stimulus. These results demonstrate that the odor of DEET or butyric acid is not intrinsically repellent to honey bees. In a second experiment, with DEET and butyric acid mixed with sucrose as an unconditioned stimulus, proboscis conditioning was not established. After several trials, few animals responded to the unconditioned stimulus. These results demonstrate that these chemicals are gustatory repellents when in direct contact. In the last experiment a conditioned suppression paradigm was used. Exposing animals to butyric acid or DEET when the proboscis was extended by direct sucrose stimulation or by learning revealed that retraction of the proboscis was similar to another novel odor, lavender, and in all cases greatest when the animal was not permitted to feed. These results again demonstrate that DEET or butyric acid are not olfactory repellents, and in addition, conditioned suppression is influenced by feeding state of the bee.

  7. Polyamines in Relation to Growth in Carrot Cell Cultures 1

    PubMed Central

    Fallon, Kevin M.; Phillips, Richard

    1988-01-01

    Changes in polyamine metabolism were investigated in relation to growth of cell suspension cultures of carrot (Daucus carota, cv Chantenay). Changes in levels of the major amines putrescine and spermidine throughout the culture period correlated poorly with changes in fresh weight, but a closer correlation with the minor component spermine was observed. The arginine decarboxylase (ADC) inhibitor difluoromethylarginine (DFMA) strongly and specifically inhibited ADC activity in the supernatant, reduced the major amine (putrescine) by 95% and the total amine content by 80%. It had no effect on cell number and stimulated fresh weight by over 25% through increased cell expansion. Spermine content, in contrast, increased with DFMA concentration in parallel with fresh weight increases. Difluoromethylornithine strongly inhibited ornithine decarboxylase activity in the pellet, but had little effect on either polyamine levels or culture growth. It was concluded that little evidence for a correlation between free polyamines and cell number in carrot cultures could be detected, but that a possible correlation between spermine content and cell expansion was observed. PMID:16666271

  8. Extraction of Am(III), Eu(III) and U(VI) from perchloric acid and mixtures of acids by dialkyl-(diaryl) [diethylcarbamoylmethyl] phosphine oxides

    SciTech Connect

    Chmutova, M.K.; Litvina, M.N.; Nesterova, N.P.; Myasoedov, B.F.; Kabachnik, M.I.

    1992-07-01

    Extraction of Am(III), and Eu(III) and U(VI) from perchloric acid solutions by dialkyl(diaryl) [diethyl-carbamoylmethyl] phosphine oxides (CMPO) has been investigated. It has been shown that elements are extracted more effectively from perchloric acid solutions than from nitric acid. An `anomalous aryl effect` increases sufficiently in perchloric media as compared with nitric media. Solvate numbers of elements also increase in perchloric acid, they being extremely high for aryl-substituted reagents and not so high for alkyl-substituted compounds. It has been shown that in HNO{sub 3} and HClO{sub 4} solutions the value of `anomalous aryl effect` directly depends on the difference in values of element solvate numbers in complexes with aryl- and alkyl-substituted CMPO. Am(III), Eu(III) and U(VI) are not practically extracted from phosphoric and sulphuric acids by CMPO solutions. 16 refs., 7 figs., 3 tabs.

  9. A preliminary study for removal of heavy metals from acidic synthetic wastewater by using pressmud-rice husk mixtures

    NASA Astrophysics Data System (ADS)

    Ahmad, H.; Ee, C. J.; Baharudin, N. S.

    2016-06-01

    The study was carried out to evaluate the effect of combining pressmud and rice husk in the removal efficiencies of heavy metals in acidic synthetic wastewater. The ratios of pressmud to rice husk were varied at different percentages of weight ratio (0%, 20%, 40%, 60% 80% and 100%) and removal of heavy metals concentrations was observed. The result showed that the removal efficiency was increased with the addition of pressmud by up to almost 100%. Pressmud alone was able to remove 95% to 100% of heavy metals while rice husk alone managed to remove only 10% to 20% of heavy metals. The study also demonstrated that pressmud behaved as a natural acid neutralizer. Hence, the initial pH of the synthetically prepared acidic wastewater which was below 2 also was increased to pH ranging from 6 to 8.

  10. Phase equilibria in four-component system consisting of water, a nonionic surfactant mixture, and oleic acid

    SciTech Connect

    Matveenko, V.N.; Drovetskii, B.Yu.; Kirasanov, E.A.

    1994-05-01

    The phase diagram of the system consisting of water, Tween 20, Span 80, and oleic acid has been obtained; the coexisting phases have been identified; and the character of the equilibrium of microemulsion, liquid crystal, and molecular solution has been described. In the water-Tween 20-oleic acid system, the ratio of the water volume to the surfactant volume is identical in all of the coexisting phases; this proves the existence of a corresponding field variable in a system with a nonionic surfactant.

  11. Effects Of Haloacetic Acid Mixtures in a Mouse Embryonic Stem Cell Adherent Cell Differentiation and Cytotoxicity (ACDC) Assay

    EPA Science Inventory

    The haloacetic acids (HAAs) are a class of chemicals produced as byproducts of drinking water disinfection. Source water characteristics (such as level of bromide) affects which HAAs are present in drinking water and their concentration. For example, high bromide-source water wil...

  12. 40 CFR 721.6440 - Polyamine urea-for-malde-hyde condensate (specific name).

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... condensate (specific name). 721.6440 Section 721.6440 Protection of Environment ENVIRONMENTAL PROTECTION... New Uses for Specific Chemical Substances § 721.6440 Polyamine urea-for-malde-hyde condensate... substance polyamine ureaformaldehyde condensate (PMN P-87-1456) is subject to reporting under this...

  13. 40 CFR 721.6440 - Polyamine urea-for-malde-hyde condensate (specific name).

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... condensate (specific name). 721.6440 Section 721.6440 Protection of Environment ENVIRONMENTAL PROTECTION... New Uses for Specific Chemical Substances § 721.6440 Polyamine urea-for-malde-hyde condensate... substance polyamine ureaformaldehyde condensate (PMN P-87-1456) is subject to reporting under this...

  14. 40 CFR 721.6440 - Polyamine urea-for-malde-hyde condensate (specific name).

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... condensate (specific name). 721.6440 Section 721.6440 Protection of Environment ENVIRONMENTAL PROTECTION... New Uses for Specific Chemical Substances § 721.6440 Polyamine urea-for-malde-hyde condensate... substance polyamine ureaformaldehyde condensate (PMN P-87-1456) is subject to reporting under this...

  15. 40 CFR 721.6440 - Polyamine urea-for-malde-hyde condensate (specific name).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... condensate (specific name). 721.6440 Section 721.6440 Protection of Environment ENVIRONMENTAL PROTECTION... New Uses for Specific Chemical Substances § 721.6440 Polyamine urea-for-malde-hyde condensate... substance polyamine ureaformaldehyde condensate (PMN P-87-1456) is subject to reporting under this...

  16. 40 CFR 721.6440 - Polyamine urea-for-malde-hyde condensate (specific name).

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... condensate (specific name). 721.6440 Section 721.6440 Protection of Environment ENVIRONMENTAL PROTECTION... New Uses for Specific Chemical Substances § 721.6440 Polyamine urea-for-malde-hyde condensate... substance polyamine ureaformaldehyde condensate (PMN P-87-1456) is subject to reporting under this...

  17. Regulation of polyamine synthesis in plants. Final progress report, July 1, 1991--December 31, 1994

    SciTech Connect

    Malmberg, R.L.

    1995-07-01

    This research focused on unusual post-translational modifications occuring in a arginine decarboxylase cDNA clone in oats. A novel regulatory mechanism for polyamines was explored and an attempt was made to characterize it. A plant ornithine decarboxylase cDNA was identified in Arabidopsis. Further work remains on the mechanisms of polyamine regulation and function in plants.

  18. Role of polyamines and phospholipase D in maize (Zea mays L.) response to drought stress

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Hydroponic experiment was conducted to elucidate the role of polyamines and phospholipase D (PLD) in regulating response of maize plants to drought stress (DS). During the early stage of DS, an increase in PLD activity, independent of polyamines contents, was mainly responsible for stomatal closure...

  19. Pacific oyster polyamine oxidase: a protein missing link in invertebrate evolution.

    PubMed

    Cervelli, Manuela; Polticelli, Fabio; Angelucci, Emanuela; Di Muzio, Elena; Stano, Pasquale; Mariottini, Paolo

    2015-05-01

    Polyamine oxidases catalyse the oxidation of polyamines and acetylpolyamines and are responsible for the polyamine interconversion metabolism in animal cells. Polyamine oxidases from yeast can oxidize spermine, N(1)-acetylspermine, and N(1)-acetylspermidine, while in vertebrates two different enzymes, namely spermine oxidase and acetylpolyamine oxidase, specifically catalyse the oxidation of spermine, and N(1)-acetylspermine/N(1)-acetylspermidine, respectively. In this work we proved that the specialized vertebrate spermine and acetylpolyamine oxidases have arisen from an ancestor invertebrate polyamine oxidase with lower specificity for polyamine substrates, as demonstrated by the enzymatic activity of the mollusc polyamine oxidase characterized here. This is the first report of an invertebrate polyamine oxidase, the Pacific oyster Crassostrea gigas (CgiPAO), overexpressed as a recombinant protein. This enzyme was biochemically characterized and demonstrated to be able to oxidase both N(1)-acetylspermine and spermine, albeit with different efficiency. Circular dichroism analysis gave an estimation of the secondary structure content and modelling of the three-dimensional structure of this protein and docking studies highlighted active site features. The availability of this pluripotent enzyme can have applications in crystallographic studies and pharmaceutical biotechnologies, including anticancer therapy as a source of hydrogen peroxide able to induce cancer cell death.

  20. Modulation of oxidative stress by γ-glutamylcysteine (GGC) and conjugated linoleic acid (CLA) isomer mixture in human umbilical vein endothelial cells.

    PubMed

    Nakamura, Yukiko K; Dubick, Michael A; Omaye, Stanley T

    2012-06-01

    Individually, γ-glutamylcysteine (GGC), a dipeptide and precursor of glutathione (GSH), and conjugated linoleic acid (CLA), a trans-fatty acid, exhibit antioxidant properties. The objective of this study was to compare effects of co-administration of GGC and CLA to treatment with GGC alone on oxidative stress and GSH synthesis in human endothelial cells. Changes in levels of 8-epi-PGF2α, thiobarbituric acid reactive substances (TBARS), GSH, total antioxidants, GSH synthetase (GSS) expression, and transcription factor DNA binding were assessed in human umbilical vein endothelial cells (HUVEC) treated with GGC alone (100 μmol/L) or combined with CLA isomer mixture (10, 50, 100 μmol/L) for 24h. Significantly higher levels of TBARS, 8-epi-PGF2α, GSH, and GSS protein were found in cells treated with GGC and 10 μmol/L CLA, compared to cells treated with GGC alone, indicative of prooxidant effects of CLA. Approximately 40% cell death was microscopically observed in cells incubated with GGC and 100 μmol/L CLA. Despite lower levels of GSH, treatment with GGC and 50 μmol/L CLA appeared to be protective from oxidative stress similar to treatment with GGC alone, as indicated by lower levels of TBARS, compared to control cells not treated with GGC and CLA.

  1. Comparative Study of Novel Ratio Spectra and Isoabsorptive Point Based Spectrophotometric Methods: Application on a Binary Mixture of Ascorbic Acid and Rutin

    PubMed Central

    Darwish, Hany W.; Bakheit, Ahmed H.; Naguib, Ibrahim A.

    2016-01-01

    This paper presents novel methods for spectrophotometric determination of ascorbic acid (AA) in presence of rutin (RU) (coformulated drug) in their combined pharmaceutical formulation. The seven methods are ratio difference (RD), isoabsorptive_RD (Iso_RD), amplitude summation (A_Sum), isoabsorptive point, first derivative of the ratio spectra (1DD), mean centering (MCN), and ratio subtraction (RS). On the other hand, RU was determined directly by measuring the absorbance at 358 nm in addition to the two novel Iso_RD and A_Sum methods. The work introduced in this paper aims to compare these different methods, showing the advantages for each and making a comparison of analysis results. The calibration curve is linear over the concentration range of 4–50 μg/mL for AA and RU. The results show the high performance of proposed methods for the analysis of the binary mixture. The optimum assay conditions were established and the proposed methods were successfully applied for the assay of the two drugs in laboratory prepared mixtures and combined pharmaceutical tablets with excellent recoveries. No interference was observed from common pharmaceutical additives. PMID:26885440

  2. Mixture of hyaluronic acid, chondroitin 6 sulphate and dermatan sulphate used to completely regenerate bone in rat critical size defect model.

    PubMed

    Zanchetta, Philippe; Lagarde, Nicole; Uguen, Arnaud; Marcorelles, Pascale

    2012-12-01

    Skeletal bone losses are mainly filled with autologous graft or artificial materials. Osteoblasts are essential to maintain bone homeostasis and bone repair through a matrix synthesis. We have previously demonstrated that adherence and regenerative matrix composition are fundamental to bone healing, even in critical situations. In this work the critical size defect technique was used to evaluate the systemic activity on bone regeneration of a novel mixture of extracellular polysaccharides. A 5mm diameter hole was made in each parietal bone of male Wistar rats. The right parietal bone hole was filled with a mixture of hyaluronic acid, chondroitin 6 sulphate, and dermatan sulphate mixed with 2.5% NaCl solution, while the left hole was left free of material and untreated and considered as control. Twenty-one days after surgery, the holes and surrounding tissues were examined visually, using X-rays, and by histological staining. Using the matrix substitute, bone healing was almost complete after 21 days in the treated hole and always complete in the control side due to some systemic effect. Neovascularization was also observed along with organized trabecular bone on both sides. No abnormal bone growth or connective tissue abnormalities were noted. At the end of the experiment, 95.1% (± 3.2) bone healing (n=20) was observed on the treated side; conversely, healing bone and histological structure were better on the control side.

  3. Anti-obesity effects of a mixture of thiamin, arginine, caffeine, and citric acid in non-insulin dependent diabetic KK mice.

    PubMed

    Muroyama, Koutarou; Murosaki, Shinji; Yamamoto, Yoshihiro; Odaka, Hiroyuki; Chung, Hee Chung; Miyoshi, Masamitsu

    2003-02-01

    Anti-obesity effects of a mixture of thiamin, arginine, caffeine, and citric acid (TACC) were investigated in non-insulin dependent diabetic KK mice. Feeding of either arginine or caffeine significantly suppressed an increase in hepatic lipid contents in fasted-refed KK mice. In addition, each component admixed with a low-calorie diet effectively reduced adipose tissue weight in KK mice previously fed a high-calorie diet. The decrease in adipose tissue weight was greater with a mixture of arginine and caffeine, and much greater with TACC than with arginine or caffeine alone. Moreover, plasma insulin concentration was significantly lower in mice fed TACC than in control mice. The anti-obesity effects of TACC were also shown when it was supplemented with a tea beverage. Adipose tissue weight, hepatic triglyceride contents, and plasma insulin concentration were significantly lower in mice given TACC-supplemented tea than in control mice. These results suggest that TACC is effective in reducing adipose tissue mass as well as improving disorders in lipid metabolism.

  4. Kinetics of moisture-induced hydrolysis in powder blends stored at and below the deliquescence relative humidity: investigation of sucrose-citric acid mixtures.

    PubMed

    Kwok, Kaho; Mauer, Lisa J; Taylor, Lynne S

    2010-11-24

    Previous studies have shown that deliquescent organic compounds frequently exhibit chemical instability when stored in environmental conditions above their deliquescence relative humidity (RH). The goal of the current study was to investigate the effect of atmospheric moisture on the long-term chemical stability of crystalline sucrose-citric acid mixtures following storage at RHs at and below the mutual deliquescence relative humidity (MDRH). Interestingly, it was found that sucrose hydrolysis can occur below the MDRH of 64% and was observed for samples stored at 54% RH. However, hydrolysis was not seen for samples stored at 33 or 43% RH. The rate of sucrose hydrolysis could be modeled by taking into account the rate and extent of moisture uptake, which in turn was dependent on the composition of the powder and the storage RH. A reaction mechanism initiated by capillary condensation and involving additional deliquescence lowering by the degradation products formed as a result of sucrose hydrolysis (glucose and fructose) was proposed.

  5. Solute-solvent interactions of acid-1,4-dioxane mixtures-By dielectric, FTIR, UV-vis and 13C NMR spectrometric methods.

    PubMed

    Arivazhagan, G; Parthipan, G; Thenappan, T

    2009-11-01

    Results of the dielectric studies carried out on the binary mixture of n-butyric and caprylic acids with 1,4-dioxane over the entire composition range and at temperatures 303K, 308K, 313K and 318K, and FTIR, UV-vis and 13C NMR spectral studies are presented in this paper. The excess permittivity and excess free energy were fitted with the Redlich-Kister polynomial. The variation of Kirkwood correlation factors, excess permittivity and excess free energy of mixing with the concentration and temperature has been investigated in view of understanding the ordering of dipoles of solute and solvent molecules. The FTIR, UV-vis and 13C NMR spectral analysis reveals the formation of complex between solute and solvent molecules. The parallel alignment of electric dipoles of the complex predicted by dielectric studies is well supported by UV-vis spectral analysis. The structure of the complex molecule present in the clusters has been deduced.

  6. Mammalian polyamine catabolism: a therapeutic target, a pathological problem, or both?

    PubMed

    Wang, Yanlin; Casero, Robert A

    2006-01-01

    With the recent discovery of the polyamine catabolic enzyme spermine oxidase (SMO/PAOh1), the apparent complexity of the polyamine metabolic pathway has increased considerably. Alone or in combination with the two other known members of human polyamine catabolism, spermidine/spermine N(1)-acetyltransferase, and N(1)-acetylpolyamine oxidase (PAO), SMO/PAOh1 expression has the potential to alter polyamine homeostasis in response to normal cellular signals, drug treatment and environmental and/or cellular stressors. The activity of the oxidases producing toxic aldehydes and the reactive oxygen species (ROS) H(2)O(2), suggest a mechanism by which these oxidases can be exploited as an antineoplastic drug target. However, inappropriate activation of the pathways may also lead to pathological outcomes, including DNA damage that can lead to cellular transformation. The most recent data suggest that the two polyamine catabolic pathways exhibit distinct properties and understanding these properties should aid in their exploitation for therapeutic and/or chemopreventive strategies.

  7. Polyamine homoeostasis as a drug target in pathogenic protozoa: peculiarities and possibilities.

    PubMed

    Birkholtz, Lyn-Marie; Williams, Marni; Niemand, Jandeli; Louw, Abraham I; Persson, Lo; Heby, Olle

    2011-09-01

    New drugs are urgently needed for the treatment of tropical and subtropical parasitic diseases, such as African sleeping sickness, Chagas' disease, leishmaniasis and malaria. Enzymes in polyamine biosynthesis and thiol metabolism, as well as polyamine transporters, are potential drug targets within these organisms. In the present review, the current knowledge of unique properties of polyamine metabolism in these parasites is outlined. These properties include prozyme regulation of AdoMetDC (S-adenosylmethionine decarboxylase) activity in trypanosomatids, co-expression of ODC (ornithine decarboxylase) and AdoMetDC activities in a single protein in plasmodia, and formation of trypanothione, a unique compound linking polyamine and thiol metabolism in trypanosomatids. Particularly interesting features within polyamine metabolism in these parasites are highlighted for their potential in selective therapeutic strategies.

  8. Polyamine homoeostasis as a drug target in pathogenic protozoa: peculiarities and possibilities

    PubMed Central

    Birkholtz, Lyn-Marie; Williams, Marni; Niemand, Jandeli; Louw, Abraham I.; Persson, Lo; Heby, Olle

    2011-01-01

    New drugs are urgently needed for the treatment of tropical and subtropical parasitic diseases, such as African sleeping sickness, Chagas' disease, leishmaniasis and malaria. Enzymes in polyamine biosynthesis and thiol metabolism, as well as polyamine transporters, are potential drug targets within these organisms. In the present review, the current knowledge of unique properties of polyamine metabolism in these parasites is outlined. These properties include prozyme regulation of AdoMetDC (S-adenosylmethionine decarboxylase) activity in trypanosomatids, co-expression of ODC (ornithine decarboxylase) and AdoMetDC activities in a single protein in plasmodia, and formation of trypanothione, a unique compound linking polyamine and thiol metabolism in trypanosomatids. Particularly interesting features within polyamine metabolism in these parasites are highlighted for their potential in selective therapeutic strategies. PMID:21834794

  9. Effect of hindlimb suspension and clenbuterol treatment on polyamine levels in skeletal muscle

    NASA Technical Reports Server (NTRS)

    Abukhalaf, Imad K.; von Deutsch, Daniel A.; Wineski, Lawrence E.; Silvestrov, Natalia A.; Abera, Saare A.; Sahlu, Sinafikish W.; Potter, David E.; Thierry-Palmer, M. (Principal Investigator)

    2002-01-01

    Polyamines are unbiquitous, naturally occurring small aliphatic, polycationic, endogenous compounds. They are involved in many cellular processes and may serve as secondary or tertiary messengers to hormonal regulation. The relationship of polyamines and skeletal muscle mass of adductor longus, extensor digitorum longus, and gastrocnemius under unloading (hindlimb suspension) conditions was investigated. Unloading significantly affected skeletal muscle polyamine levels in a fiber-type-specific fashion. Under loading conditions, clenbuterol treatment increased all polyamine levels, whereas under unloading conditions, only the spermidine levels were consistently increased. Unloading attenuated the anabolic effects of clenbuterol in predominately slow-twitch muscles (adductor longus), but had little impact on clenbuterol's action as a countermeasure in fast- twitch muscles such as the extensor digitorum longus. Spermidine appeared to be the primary polyamine involved in skeletal muscle atrophy/hypertrophy. Copyright 2002 S. Karger AG, Basel.

  10. Real-Time Investigation of Chemical Compositions and Hygroscopic Properties of Aerosols Generated from NaCl and Malonic Acid Mixture Solutions Using in Situ Raman Microspectrometry.

    PubMed

    Li, Xue; Gupta, Dhrubajyoti; Lee, Jisoo; Park, Geonhee; Ro, Chul-Un

    2017-01-03

    Recently, ambient sea spray aerosols (SSAs) have been reported to undergo reactions with dicarboxylic acids (DCAs). Several studies have examined the hygroscopic behavior and chemical reactivity of aerosols generated from NaCl-DCA mixture solutions, but the results have varied, especially for the NaCl-malonic acid (NaCl-MA) mixture system. In this work, in situ Raman microspectrometry (RMS) was used to simultaneously monitor the change in chemical composition, size, and phase as a function of the relative humidity, for individual aerosols generated from NaCl-MA solutions, during two hygroscopic measurement cycles, which were performed first through the dehydration process, followed by a humidification process, in each cycle. In situ RMS analysis for the aerosols showed that the chemical reaction between NaCl and MA occurred rapidly in the time scale of 1 h and considerably in the aqueous phase, mostly during the first dehydration process, and the chemical reaction occurs more rapidly when MA is more enriched in the aerosols. For example, the reaction between NaCl and MA for aerosols generated from solutions of NaCl:MA = 2:1 and 1:2 occurred by 81% and 100% at RH = 42% and 45%, respectively, during the first dehydration process. The aerosols generated from the solution of NaCl:MA = 2:1 revealed single efflorescence and deliquescence transitions repeatedly during two hygroscopic cycles. The aerosols from NaCl:MA = 1:1 and 1:2 solutions showed just an efflorescence transition during the first dehydration process and no efflorescence and deliquescence transition during the hygroscopic cycles, respectively. The observed different hygroscopic behavior was due to the different contents of NaCl, MA, and monosodium malonate in the aerosols, which were monitored real-time by in situ RMS.

  11. Cotton polyamine oxidase is required for spermine and camalexin signalling in the defence response to Verticillium dahliae.

    PubMed

    Mo, Huijuan; Wang, Xingfen; Zhang, Yan; Zhang, Guiyin; Zhang, Jinfa; Ma, Zhiying

    2015-09-01

    Verticillium dahliae is a destructive, soil-borne fungal pathogen that causes vascular wilt disease in many economically important crops worldwide. A polyamine oxidase (PAO) gene was identified and cloned by screening suppression subtractive hybridisation and cDNA libraries of cotton genotypes tolerant to Verticillium wilt and was induced early and strongly by inoculation with V. dahliae and application of plant hormone. Recombinant cotton polyamine oxidase (GhPAO) was found to catalyse the conversion of spermine (Spm) to spermidine (Spd) in vitro. Constitutive expression of GhPAO in Arabidopsis thaliana produced improved resistance to V. dahliae and maintained putrescine, Spd and Spm at high levels. Hydrogen peroxide (H2 O2 ), salicylic acid and camalexin (a phytoalexin) levels were distinctly increased in GhPAO-overexpressing Arabidopsis plants during V. dahliae infection when compared with wild-type plants, and Spm and camalexin efficiently inhibited growth of V. dahliae in vitro. Spermine promoted the accumulation of camalexin by inducing the expression of mitogen-activated protein kinases and cytochrome P450 proteins in Arabidopsis and cotton plants. The three polyamines all showed higher accumulation in tolerant cotton cultivars than in susceptible cotton cultivars after inoculation with V. dahliae. GhPAO silencing in cotton significantly reduced the Spd level and increased the Spm level, leading to enhanced susceptibility to infection by V. dahliae, and the levels of H2 O2 and camalexin were distinctly lower in GhPAO-silenced cotton plants after V. dahliae infection. Together, these results suggest that GhPAO contributes to resistance of the plant against V. dahliae through the mediation of Spm and camalexin signalling.

  12. Dietary polyamine intake and colorectal cancer risk in postmenopausal women12

    PubMed Central

    Vargas, Ashley J; Ashbeck, Erin L; Wertheim, Betsy C; Wallace, Robert B; Neuhouser, Marian L; Thomson, Cynthia A; Thompson, Patricia A

    2015-01-01

    Background: Putrescine, spermidine, and spermine (i.e., polyamines) are small cationic amines synthesized by cells or acquired from the diet or gut bacteria. Polyamines are required for both normal and colorectal cancer (CRC) cell growth. Objective: We investigated the association between dietary polyamines and risk of CRC incidence and mortality. Design: The study was a prospective analysis in 87,602 postmenopausal women in the Women’s Health Initiative Observational Study. Multivariate Cox regression was used to calculate HRs and 95% CIs. Results: Total dietary polyamine intake (mean ± SD: 289.2 ± 127.4 μmol/d) was not positively associated with CRC in fully adjusted models. Instead, intake ≥179.67 μmol/d was associated with reduced risk of CRC [HR (95% CI): 0.82 (0.68, 1.00), 0.81 (0.66, 0.99), 0.91 (0.74, 1.12), and 0.80 (0.62, 1.02) for quintiles 2–5, respectively, compared with quintile 1]. Reduced risk was not significant across all quintiles. Polyamines were not significantly associated with CRC-specific mortality in fully adjusted models. When stratified by risk factors for CRC, only body mass index (BMI) and fiber intake significantly modified the association between polyamine intake and CRC. In women with BMI (in kg/m2) ≤25 or fiber consumption above the median, polyamine intake was associated with significantly lower risk of CRC. Conclusions: No positive association between dietary polyamines and CRC or CRC-specific mortality risk in women was observed. Instead, a protective effect of dietary polyamines was suggested in women with some CRC risk-lowering behaviors in particular. These results are consistent with emerging evidence that exogenous polyamines may be beneficial in colon health and warrant additional study. PMID:26135350

  13. Regulation of estrogenic and nuclear factor kappa B functions by polyamines and their role in polyamine analog-induced apoptosis of breast cancer cells.

    PubMed

    Shah, N; Thomas, T J; Lewis, J S; Klinge, C M; Shirahata, A; Gelinas, C; Thomas, T

    2001-03-29

    The natural polyamines -putrescine, spermidine, and spermine- are essential for cell growth and differentiation. Polyamines are involved in several gene regulatory functions, although their mechanism(s) of action has not been elucidated. We investigated the role of polyamines in the function of NF-kappa B and estrogen receptor-alpha (ER alpha), two transcription factors implicated in breast cancer cell proliferation and cell survival, using MCF-7 breast cancer cells. We found that spermine facilitated the binding of ER alpha and NF-kappa B to estrogen response element (ERE)- and NF-kappa B response element (NRE), respectively, and enhanced ER alpha-mediated transcriptional activation in transient transfection experiments. We also found that the association of the co-regulatory protein CBP/p300 with ER alpha and NF-kappa B was increased by spermine treatment of MCF-7 cells. Spermine also increased the nuclear translocation of NF-kappa B compared to the control. In contrast, treatment of MCF-7 cells with polyamine analogs, BE-3-4-3 and BE-3-3-3, resulted in transcriptional inhibition of both ERE- and NRE-driven reporter plasmids. In addition, polyamine analogs inhibited the association of ER alpha and NF-kappa B with CBP/p300 and were unable to facilitate nuclear translocation of NF-kappa B. APO-BRDU assay demonstrated that polyamine analogs induced apoptosis, with a loss of the anti-apoptotic protein Bcl-2. These data show a gene regulatory function of polyamines involving transcriptional activation of ER alpha and NF-kappa B, potentially leading to the up-regulation of genes involved in breast cancer cell proliferation. Our results with BE-3-4-3 and BE-3-3-3 suggest that down-regulation of ER alpha- and NF-kappa B-regulated genes is a possible mechanism for the action of polyamine analogs in inducing apoptosis of breast cancer cells.

  14. Assessing the bioremediation potential of algal species indigenous to oil sands process-affected waters on mixtures of oil sands acid extractable organics.

    PubMed

    Ruffell, Sarah E; Frank, Richard A; Woodworth, Adam P; Bragg, Leslie M; Bauer, Anthony E; Deeth, Lorna E; Müller, Kirsten M; Farwell, Andrea J; Dixon, D George; Servos, Mark R; McConkey, Brendan J

    2016-11-01

    Surface mining extraction of bitumen from oil sand in Alberta, Canada results in the accumulation of oil sands process-affected water (OSPW). In attempts to maximize water recycling, and because its constituents are recognized as being toxic, OSPW is retained in settling basins. Consequently, research efforts are currently focused on developing remediation strategies capable of detoxifying OSPW to allow for eventual release. One potential bioremediation strategy proposes to utilize phytoplankton native to the Alberta oil sand region to sequester, break down, or modify the complex oil sands acid extractable organic (AEO) mixtures in OSPW. Preliminary attempts to quantify changes in total oil sands AEO concentration in test solutions by ESI-MS following a 14-day algal remediation period revealed the presence of unknown organic acids in control samples, likely released by the phytoplankton strains and often of the same atomic mass range as the oil sands AEO under investigation. To address the presence of these "biogenic" organic acids in test samples, ESI-MS in MRM mode was utilized to identify oil sands AEO "marker ions" that were a) present within the tested oil sands AEO extract and b) unique to the oil sands AEO extract only (e.g. atomic masses different from biogenic organic acids). Using this approach, one of the 21 tested algal strains, Stichococcus sp. 1, proved capable of significantly reducing the AEO marker ion concentration at test concentrations of 10, 30, and 100mgL(-1). This result, along with the accelerated growth rate and recalcitrance of this algal strain with exposure to oil sands AEO, suggests the strong potential for the use of the isolated Stichococcus sp. 1 as a candidate for bioremediation strategies.

  15. Tuning the degradation rate of calcium phosphate cements by incorporating mixtures of polylactic-co-glycolic acid microspheres and glucono-delta-lactone microparticles.

    PubMed

    Sariibrahimoglu, Kemal; An, Jie; van Oirschot, Bart A J A; Nijhuis, Arnold W G; Eman, Rhandy M; Alblas, Jacqueline; Wolke, Joop G C; van den Beucken, Jeroen J J P; Leeuwenburgh, Sander C G; Jansen, John A

    2014-11-01

    Calcium phosphate cements (CPCs) are frequently used as synthetic bone graft materials in view of their excellent osteocompatibility and clinical handling behavior. Hydroxyapatite-forming CPCs, however, degrade at very low rates, thereby limiting complete bone regeneration. The current study has investigated whether degradation of apatite-forming cements can be tuned by incorporating acid-producing slow-resorbing poly(D,L-lactic-co-glycolic) acid (PLGA) porogens, fast-resorbing glucono-delta-lactone (GDL) porogens, or mixtures thereof. The physicochemical, mechanical, and degradation characteristics of these CPC formulations were systematically analyzed upon soaking in phosphate-buffered saline (PBS). In parallel, various CPC formulations were implanted intramuscularly and orthotopically on top of the transverse process of goats followed by analysis of the soft tissue response and bone ingrowth after 12 weeks. In vitro degradation of GDL was almost completed after 2 weeks, as evidenced by characterization of the release of gluconic acid, while PLGA-containing CPCs released glycolic acid throughout the entire study (12 weeks), resulting in a decrease in compression strength of CPC. Extensive in vitro degradation of the CPC matrix was observed upon simultaneous incorporation of 30% PLGA-10% GDL. Histomorphometrical evaluation of the intramuscularly implanted samples revealed that all CPCs exhibited degradation, accompanied by an increase in capsule thickness. In the in vivo goat transverse process model, incorporation of 43% PLGA, 30% PLGA-5% GDL, and 30% PLGA-10% GDL in CPC significantly increased bone formation and resulted in higher bone height compared with both 10% GDL and 20% GDL-containing CPC samples.

  16. Hydroxycarboxylic acids and salts

    DOEpatents

    Kiely, Donald E; Hash, Kirk R; Kramer-Presta, Kylie; Smith, Tyler N

    2015-02-24

    Compositions which inhibit corrosion and alter the physical properties of concrete (admixtures) are prepared from salt mixtures of hydroxycarboxylic acids, carboxylic acids, and nitric acid. The salt mixtures are prepared by neutralizing acid product mixtures from the oxidation of polyols using nitric acid and oxygen as the oxidizing agents. Nitric acid is removed from the hydroxycarboxylic acids by evaporation and diffusion dialysis.

  17. The chemistry of escapin: identification and quantification of the components in the complex mixture generated by an L-amino acid oxidase in the defensive secretion of the sea snail Aplysia californica.

    PubMed

    Kamio, Michiya; Ko, Ko-Chun; Zheng, Shilong; Wang, Binghe; Collins, Stacy L; Gadda, Giovanni; Tai, Phang C; Derby, Charles D

    2009-01-01

    Escapin is an L-amino acid oxidase in the ink of a marine snail, the sea hare Aplysia californica, which oxidizes L-lysine (1) to produce a mixture of chemicals which is antipredatory and antimicrobial. The goal of our study was to determine the identity and relative abundance of the constituents of this mixture, using molecules generated enzymatically with escapin and also using products of organic syntheses. We examined this mixture under the natural range of pH values for ink-from approximately 5 at full strength to approximately 8 when fully diluted in sea water. The enzymatic reaction likely forms an equilibrium mixture containing the linear form alpha-keto-epsilon-aminocaproic acid (2), the cyclic imine Delta(1)-piperidine-2-carboxylic acid (3), the cyclic enamine Delta(2)-piperidine-2-carboxylic acid (4), possibly the linear enol 6-amino-2-hydroxy-hex-2-enoic acid (7), the alpha-dihydroxy acid 6-amino-2,2-dihydroxy-hexanoic acid (8), and the cyclic aminol 2-hydroxy-piperidine-2-carboxylic acid (9). Using NMR and mass spectroscopy, we show that 3 is the major component of this enzymatic product at any pH, but at more basic conditions, the equilibrium shifts to produce relatively more 4, and at acidic conditions, the equilibrium shifts to produce relatively more 2, 7, and/or 9. Studies of escapin's enzyme kinetics demonstrate that because of the high concentrations of escapin and L-lysine in the ink secretion, millimolar concentrations of 3, H(2)O(2), and ammonia are produced, and also lower concentrations of 2, 4, 7, and 9 as a result. We also show that reactions of this mixture with H(2)O(2) produce delta-aminovaleric acid (5) and delta-valerolactam (6), with 6 being the dominant component under the naturally acidic conditions of ink. Thus, the product of escapin's action on L-lysine contains an equilibrium mixture that is more complex than previously known for any L-amino acid oxidase.

  18. Extraction of Lanthanide and Actinide Ions from Aqueous Mixtures Using a Carboxylic Acid-Functionalized Porous Aromatic Framework.

    PubMed

    Demir, Selvan; Brune, Nicholas K; Van Humbeck, Jeffrey F; Mason, Jarad A; Plakhova, Tatiana V; Wang, Shuao; Tian, Guoxin; Minasian, Stefan G; Tyliszczak, Tolek; Yaita, Tsuyoshi; Kobayashi, Tohru; Kalmykov, Stepan N; Shiwaku, Hideaki; Shuh, David K; Long, Jeffrey R

    2016-04-27

    Porous aromatic frameworks (PAFs) incorporating a high concentration of acid functional groups possess characteristics that are promising for use in separating lanthanide and actinide metal ions, as required in the treatment of radioactive waste. These materials have been shown to be indefinitely stable to concentrated acids and bases, potentially allowing for multiple adsorption/stripping cycles. Additionally, the PAFs combine exceptional features from MOFs and inorganic/activated carbons giving rise to tunable pore surfaces and maximum chemical stability. Herein, we present a study of the adsorption of selected metal ions, Sr(2+), Fe(3+), Nd(3+), and Am(3+), from aqueous solutions employing a carbon-based porous aromatic framework, BPP-7 (Berkeley Porous Polymer-7). This material displays high metal loading capacities together with excellent adsorption selectivity for neodymium over strontium based on Langmuir adsorption isotherms and ideal adsorbed solution theory (IAST) calculations. Based in part upon X-ray absorption spectroscopy studies, the stronger adsorption of neodymium is attributed to multiple metal ion and binding site interactions resulting from the densely functionalized and highly interpenetrated structure of BPP-7. Recyclability and combustibility experiments demonstrate that multiple adsorption/stripping cycles can be completed with minimal degradation of the polymer adsorption capacity.

  19. Extraction of Lanthanide and Actinide Ions from Aqueous Mixtures Using a Carboxylic Acid-Functionalized Porous Aromatic Framework

    PubMed Central

    2016-01-01

    Porous aromatic frameworks (PAFs) incorporating a high concentration of acid functional groups possess characteristics that are promising for use in separating lanthanide and actinide metal ions, as required in the treatment of radioactive waste. These materials have been shown to be indefinitely stable to concentrated acids and bases, potentially allowing for multiple adsorption/stripping cycles. Additionally, the PAFs combine exceptional features from MOFs and inorganic/activated carbons giving rise to tunable pore surfaces and maximum chemical stability. Herein, we present a study of the adsorption of selected metal ions, Sr2+, Fe3+, Nd3+, and Am3+, from aqueous solutions employing a carbon-based porous aromatic framework, BPP-7 (Berkeley Porous Polymer-7). This material displays high metal loading capacities together with excellent adsorption selectivity for neodymium over strontium based on Langmuir adsorption isotherms and ideal adsorbed solution theory (IAST) calculations. Based in part upon X-ray absorption spectroscopy studies, the stronger adsorption of neodymium is attributed to multiple metal ion and binding site interactions resulting from the densely functionalized and highly interpenetrated structure of BPP-7. Recyclability and combustibility experiments demonstrate that multiple adsorption/stripping cycles can be completed with minimal degradation of the polymer adsorption capacity. PMID:27163056

  20. The mixture of liquid foam soap, ethanol and citric acid as a new fixative-preservative solution in veterinary anatomy.

    PubMed

    Turan, Erkut; Gules, Ozay; Kilimci, Figen Sevil; Kara, Mehmet Erkut; Dilek, Omer Gurkan; Sabanci, Seyyid Said; Tatar, Musa

    2017-01-01

    The present study investigates the efficiency of liquid foam soap, ethanol, citric acid and benzalkonium chloride as a fixative-preservative solution (a soap-and ethanol-based fixing solution, or SEFS). In this study, ethanol serves as the fixative and preservative, liquid foam soap as the modifying agent, citric acid as the antioxidant and benzalkonium chloride as the disinfectant. The goat cadavers perfused with SEFS (n=8) were evaluated over a period of one year with respect to hardness, colour and odour using objective methods. Colour and hardness were compared between one fresh cadaver and the SEFS-embalmed cadavers. Histological and microbiological examinations were also performed in tissue samples. Additionally, the cadavers were subjectively evaluated after dissection and palpation. The SEFS provided the effectiveness expected over a 1-year embalming period for the animal cadavers. No bacteria or fungi were isolated except for some non-pathogenic Bacillus species. Visible mould was not present on either cadavers or in the surrounding environment. The cadavers maintained an appearance close to their original anatomical appearance, with muscles having good hardness and elasticity for dissection.

  1. Insulinogenic sucrose+amino acid mixture ingestion immediately after resistance exercise has an anabolic effect on bone compared with non-insulinogenic fructose+amino acid mixture in growing rats.

    PubMed

    Notomi, Takuya; Karasaki, Ikuaki; Okazaki, Yuichi; Okimoto, Nobukazu; Kato, Yushi; Ohura, Kiyoshi; Noda, Masaki; Nakamura, Toshitaka; Suzuki, Masashige

    2014-08-01

    Maximizing peak bone mass is an important factor in osteoporosis prevention. Resistance exercise increases bone mass and strength, while nutritional supplements have beneficial effects on bone loss reduction. We have previously shown that the combined intake of sucrose and amino acids (AA), which is strongly insulinogenic, efficiently increased muscle protein synthesis. To investigate the effects of sugar and an AA solution immediately after resistance exercise, we compared insulinogenic sucrose and non-insulinogenic fructose combined with an AA solution with or without resistance exercise. Sucrose intake immediately after resistance exercise increased the trabecular bone mass and compressive maximum load compared with fructose+AA intake after exercise. Additionally, combined sucrose+AA and exercise increased trabecular bone formation and decreased bone resorption more than combined fructose and exercise. Serum insulin levels were greatly increased by sucrose+AA intake with exercise. In culture experiments, neither sugar+AA affected osteoblast and osteoclast differentiation. In a gene expression study, sucrose+AA intake after resistance exercise was shown to upregulate the Runx2 expression level and decrease RANKL/OPG ratio. These results suggest that the combined intake of sucrose and an AA solution immediately after resistance exercise exerts anabolic effects on bone by altering gene expression related to bone remodeling. Although translation of our bone remodeling findings from animal to human studies has been challenging, our findings suggest that exercise with sugar+AA intake may contribute to improved bone health.

  2. Probing TARP modulation of AMPA receptor conductance with polyamine toxins.

    PubMed

    Jackson, Alexander C; Milstein, Aaron D; Soto, David; Farrant, Mark; Cull-Candy, Stuart G; Nicoll, Roger A

    2011-05-18

    The properties of synaptic AMPA receptors (AMPARs) depend on their subunit composition and association with transmembrane AMPAR regulatory proteins (TARPs). Although both GluA2 incorporation and TARP association have been shown to influence AMPAR channel conductance, the manner in which different TARPs modulate the mean channel conductance of GluA2-containing AMPARs is unknown. Using ultrafast agonist application and nonstationary fluctuation analysis, we found that TARP subtypes differentially increase the mean channel conductance, but not the peak open probability, of recombinant GluA2-containing AMPARs. TARP γ-8, in particular, enhances mean channel conductance to a greater degree than γ-2, γ-3, or γ-4. We then examined the action of a use-dependent antagonist of GluA2-containing AMPARs, philanthotoxin-74 (PhTx-74), on recombinant AMPARs and on GluA2-containing AMPARs in cerebellar granule neurons from stargazer mice transfected with TARPs. We found that the rate and extent of channel block varies with TARP subtype, in a manner that correlates linearly with mean channel conductance. Furthermore, block of GluA2-containing AMPARs by polyamine toxins varied depending on whether channels were activated by the full agonist glutamate or the partial agonist kainate, consistent with conductance state-dependent block. Block of GluA2-lacking AMPARs by PhTx-433 is also modulated by TARP association and is a function of agonist efficacy. Our data indicate that channel block by polyamine toxins is sensitive to the mean channel conductance of AMPARs, which varies with TARP subtype and agonist efficacy. Furthermore, our results illustrate the utility of polyamine toxins as sensitive probes of AMPAR channel conductance and suggest the possibility that TARPs may influence their channel properties by selectively stabilizing specific channel conformations, rather than altering the pore structure.

  3. Androgenic control of polyamine concentrations in rat epididymis.

    PubMed

    de las Heras, M A; Gonzalez, S I; Calandra, R S

    1992-09-01

    Unilateral orchidectomy resulted in a significant decrease in tissue content of putrescine and polyamines. However, no differences were detected when the results were expressed in terms of ng g-1 tissue. At 48 h after bilateral orchidectomy, a significant decrease in putrescine content was observed, but spermidine and spermine content were unaffected. The observed decrease in putrescine was prevented by treatment with testosterone propionate, but neither spermidine nor spermine were affected. Bilateral orchidectomy resulted in a significant decrease in the tissue content of putrescine, spermidine and spermine after 7 days. Treatment with testosterone propionate increased the content of putrescine, spermidine and spermine in the epididymis by about 200%, 92% and 34%, respectively. When results were expressed as nmol g-1, a significant decrease after castration in putrescine and spermidine, but not in spermine, was observed. Treatment with testosterone propionate restored putrescine concentration, but had no effect on spermidine and spermine concentrations. In castrated rats treated with testosterone propionate, the anti-androgen flutamide abolished the effect of the androgen on putrescine and spermidine content, but there was no effect on spermine. Acetylputrescine was not detected in the epididymis, while acetylpolyamines were detected at much lower concentrations than polyamines. After bilateral orchidectomy there was a decrease in the tissue content of all acetylpolyamines and an increase in their tissue concentration. The effect of castration on acetylpolyamine content was reversed by testosterone propionate treatment. We conclude that an active synthesis of polyamines occurs in the rat epididymis, and that this process depends upon the androgen environment. Regulation of ornithine decarboxylase activity appears to be the main step that is controlled by androgens.

  4. Liquid chromatography method to determine polyamines in thermosetting polymers.

    PubMed

    Dopico-García, M S; López-Vilariño, J M; Fernández-Martínez, G; González-Rodríguez, M V

    2010-05-14

    A simple, robust and sensitive analytical method to determine three polyamines commonly used as hardeners in epoxy resin systems and in the manufacture of polyurethane is reported. The studied polyamines are: one tetramine, TETA (triethylenetetramine), and two diamines, IPDA (Isophorone diamine) and TCD-diamine (4,7-methano-1H-indene-5,?-dimethanamine, octahydro-). The latter has an incompletely defined structure, and, as far as we know, has not been previously determined by other methods. All three polyamines contain primary amines; TETA also contains secondary amines. The analytical method involves derivatization with 6-aminoquinolyl-N-hydroxysuccinimidyl carbamate, used for the first time for these compounds, followed by high performance liquid chromatography (HPLC) analysis with a fluorescence (FL) detector (lambda excitation 248nm, lambda emision 395nm). The HPLC-DAD-LTQ Orbitrap MS was used in order to provide structural information about the obtained derivatized compounds. The hybrid linear ion trap LTQ Orbitrap mass spectrometer has been introduced in recent years and provides a high mass accuracy. The structures of the derivatized analytes were identified from the protonated molecular ions [M+H](+) and corresponded to the fully labelled analytes. The following analytical parameters were determined for the method using the HPLC-FL: linearity, precision (2.5-10%), instrumental precision intraday (0.8-1.5%) and interday (2.9-6.3%), and detection limits (0.02-0.14mgL(-1)). The stability of stock solutions and derivatized compounds was also investigated. The method was applied to determine the amine free content in epoxy resin dust collected in workplaces.

  5. Comparison of soybean cultivars for enhancement of the polyamine contents in the fermented soybean natto using Bacillus subtilis (natto).

    PubMed

    Kobayashi, Kazuya; Horii, Yuichiro; Watanabe, Satoshi; Kubo, Yuji; Koguchi, Kumiko; Hoshi, Yoshihiro; Matsumoto, Ken-Ichi; Soda, Kuniyasu

    2017-03-01

    Polyamines have beneficial properties to prevent aging-associated diseases. Raw soybean has relatively high polyamine contents; and the fermented soybean natto is a good source of polyamines. However, detailed information of diversity of polyamine content in raw soybean is lacking. The objectives of this study were to evaluate differences of polyamines among raw soybeans and select the high polyamine-containing cultivar for natto production. Polyamine contents were measured chromatographically in 16 samples of soybean, which showed high variation among soybeans as follows: 93-861 nmol/g putrescine, 1055-2306 nmol/g spermidine, and 177-578 nmol/g spermine. We then confirmed the high correlations of polyamine contents between raw soybean and natto (r = 0.96, 0.95, and 0.94 for putrescine, spermidine, and spermine, respectively). Furthermore, comparison of the polyamine contents among 9 Japanese cultivars showed that 'Nakasen-nari' has the highest polyamine contents, suggesting its suitability for enhancement of polyamine contents of natto.

  6. The roles of polyamines during the lifespan of plants: from development to stress.

    PubMed

    Tiburcio, Antonio F; Altabella, Teresa; Bitrián, Marta; Alcázar, Rubén

    2014-07-01

    Compelling evidence indicates that free polyamines (PAs) (mainly putrescine, spermidine, spermine, and its isomer thermospermine), some PA conjugates to hydroxycinnamic acids, and the products of PA oxidation (hydrogen peroxide and γ-aminobutyric acid) are required for different processes in plant development and participate in abiotic and biotic stress responses. A tight regulation of PA homeostasis is required, since depletion or overaccumulation of PAs can be detrimental for cell viability in many organisms. In plants, homeostasis is achieved by modulation of PA biosynthesis, conjugation, catabolism, and transport. However, recent data indicate that such mechanisms are not mere modulators of PA pools but actively participate in PA functions. Examples are found in the spermidine-dependent eiF5A hypusination required for cell division, PA hydroxycinnamic acid conjugates required for pollen development, and the involvement of thermospermine in cell specification. Recent advances also point to implications of PA transport in stress tolerance, PA-dependent transcriptional and translational modulation of genes and transcripts, and posttranslational modifications of proteins. Overall, the molecular mechanisms identified suggest that PAs are intricately coordinated and/or mediate different stress and developmental pathways during the lifespan of plants.

  7. Polyamine Homeostasis in Wild Type and Phenolamide Deficient Arabidopsis thaliana Stamens

    PubMed Central

    Fellenberg, Christin; Ziegler, Jörg; Handrick, Vinzenz; Vogt, Thomas

    2012-01-01

    Polyamines (PAs) like putrescine, spermidine, and spermine are ubiquitous polycationic molecules that occur in all living cells and have a role in a wide variety of biological processes. High amounts of spermidine conjugated to hydroxycinnamic acids are detected in the tryphine of Arabidopsis thaliana pollen grains. Tapetum localized spermidine hydroxycinnamic acid transferase (SHT) is essential for the biosynthesis of these anther specific tris-conjugated spermidine derivatives. Sht knockout lines show a strong reduction of hydroxycinnamic acid amides (HCAAs). The effect of HCAA-deficient anthers on the level of free PAs was measured by a new sensitive and reproducible method using 9-fluorenylmethyl chloroformate (FMOC) and fluorescence detection by HPLC. PA concentrations can be accurately determined even when very limited amounts of plant material, as in the case of A. thaliana stamens, are available. Analysis of free PAs in wild type stamens compared to sht deficient mutants and transcript levels of key PA biosynthetic genes revealed a highly controlled regulation of PA homeostasis in A. thaliana anthers. PMID:22912643

  8. Thermodynamics of aqueous borate solutions I. Mixture of boric acid with sodium or potassium borate and chloride

    SciTech Connect

    Simonson, J.M.; Roy, R.N.; Roy, L.N.; Johnson, D.A.

    1987-10-01

    Potentials for the cell without liquid junction H/sub 2/, Ptlt. slashB(OH)/sub 3/(m/sub 1/),MB(OH)/sub 4/(m/sub 2/),MCl(m/sub 3/)lt. slashAgCl,Ag where M is sodium or potassium are reported over a range of ionic strength to I = 3 mol-kg/sup -1/ at 5 to 55/sup 0/C. Total boron concentration in the solutions was restricted to low levels to minimize formation of polynuclear boron species. Cell potentials are treated with the Pitzer ion interaction treatment for mixed electrolytes, with linear ionic strength dependence assumed for the activity coefficient of undissociated boric acid. Trace activity coefficients of sodium and potassium borates in chloride media are calculated at various temperatures.

  9. Melt crystallization for refinement of triolein and palmitic acid mixture as a model waste oil for biodiesel fuel production

    NASA Astrophysics Data System (ADS)

    Fukui, Keisuke; Maeda, Kouji; Kuramochi, Hidetoshi

    2013-06-01

    Melt crystallization using an annular vessel with two circular cylinders was applied to produce high-quality vegetable oil from waste oil. The inner cylinder was cooled at a constant rate and rotated, and the outer cylinder was heated at a constant temperature. The melt was solidified on the inner cylinder surface. The binary system of triolein and palmitic acid was used as the model waste oil. We measured the distribution coefficient of triolein. Suitable operation conditions were proposed to attain a high yield and a high purity of triolein from waste oil. The distribution coefficient correlated well with the theoretical equation derived on the basis of the "local lever rule" at the interface of the crystal layer and melt [1].

  10. Cell-free expression of the APP transmembrane fragments with Alzheimer's disease mutations using algal amino acid mixture for structural NMR studies.

    PubMed

    Bocharova, Olga V; Urban, Anatoly S; Nadezhdin, Kirill D; Bocharov, Eduard V; Arseniev, Alexander S

    2016-07-01

    Structural investigations need ready supply of the isotope labeled proteins with inserted mutations n the quantities sufficient for the heteronuclear NMR. Though cell-free expression system has been widely used in the past years, high startup cost and complex compound composition prevent many researches from the developing this technique, especially for membrane protein production. Here we demonstrate the utility of a robust, cost-optimized cell-free expression technique for production of the physiologically important transmembrane fragment of amyloid precursor protein, APP686-726, containing Alzheimer's disease mutations in the juxtamembrane (E693G, Arctic form) and the transmembrane parts (V717G, London form, or L723P, Australian form). The protein cost was optimized by varying the FM/RM ratio as well as the amino acid concentration. We obtained the wild-type and mutant transmembrane fragments in the pellet mode of continuous exchange cell-free system consuming only commercial algal mixture of the (13)C,(15)N-labeled amino acids. Scaling up analytical tests, we achieved milligram quantity yields of isotope labeled wild-type and mutant APP686-726 for structural studies by high resolution NMR spectroscopy in membrane mimicking environment. The described approach has from 5 to 23-fold cost advantage over the bacterial expression methods described earlier and 1.5 times exceeds our previous result obtained with the longer APP671-726WT fragment.

  11. Formation of molecular complexes of salicylic acid, acetylsalicylic acid, and methyl salicylate in a mixture of supercritical carbon dioxide with a polar cosolvent

    NASA Astrophysics Data System (ADS)

    Petrenko, V. E.; Antipova, M. L.; Gurina, D. L.; Odintsova, E. G.

    2015-08-01

    The solvate structures formed by salicylic acid, acetylsalicylic acid, and methyl salicylate in supercritical (SC) carbon dioxide with a polar cosolvent (methanol, 0.03 mole fractions) at a density of 0.7 g/cm3 and a temperature of 318 K were studied by the molecular dynamics method. Salicylic and acetylsalicylic acids were found to form highly stable hydrogen-bonded complexes with methanol via the hydrogen atom of the carboxyl group. For methyl salicylate in which the carboxyl hydrogen is substituted by a methyl radical, the formation of stable hydrogen bonds with methanol was not revealed. The contribution of other functional groups of the solute to the interactions with the cosolvent was much smaller. An analysis of correlations between the obtained data and the literature data on the cosolvent effect on the solubility of the compounds in SC CO2 showed that the dissolving ability of SC CO2 with respect to a polar organic substance in the presence of a cosolvent increased only when stable hydrogen-bonded complexes are formed between this substance and the cosolvent.

  12. Low-temperature derivatization followed by vortex-assisted liquid-liquid microextraction for the analysis of polyamines in Nicotiana Tabacum.

    PubMed

    Cai, Kai; Cai, Bin; Xiang, Zhangmin; Zhao, Huina; Rao, Xingyi; Pan, Wenjie; Lei, Bo

    2016-07-01

    Polyamines are ubiquitous polycationic molecules that play a key role in many biological processes such as nucleic acid metabolism, protein synthesis, cell growth, and nicotine synthesis precursors. This work describes a rapid, sensitive, convenient, green, and cost-effective method for the determination of polyamines in Nicotiana tabacum by ultra high performance liquid chromatography with photodiode array detection. The analytes were derivatized with 3,5-dinitrobenzoyl chloride at low temperature (about 4°C) and then extracted with vortex-assisted liquid-liquid microextraction. The experimental designs based on quarter-fractional factorial design and Doehlert design were used to screen and optimize the important factors in microextraction process. Under the optimal conditions, the method was linear over 0.05-8.00 μg/mL with an r(2) ≥ 0.992 and exhibited good repeatability and reproducibility less than 6.0 and 6.9%, respectively. The limit of detection ranged between 0.013 and 0.029 μg/g. The newly developed method was successfully employed to analyze different leaf samples of Nicotiana tabacum, among which the polyamines contents were found to be very different. Moreover, tyramine, 1,3-diaminopropane, homospermidine, and canavalmine were tentatively identified with the electrospray ionization quadrupole time-of-flight mass spectrometry. To our knowledge, this is the first report of identification of canavalmine in Nicotiana Tabacum.

  13. Probiotic viability and storage stability of yogurts and fermented milks prepared with several mixtures of lactic acid bacteria.

    PubMed

    Mani-López, E; Palou, E; López-Malo, A

    2014-05-01

    Currently, the food industry wants to expand the range of probiotic yogurts but each probiotic bacteria offers different and specific health benefits. Little information exists on the influence of probiotic strains on physicochemical properties and sensory characteristics of yogurts and fermented milks. Six probiotic yogurts or fermented milks and 1 control yogurt were prepared, and we evaluated several physicochemical properties (pH, titratable acidity, texture, color, and syneresis), microbial viability of starter cultures (Lactobacillus delbrueckii ssp. bulgaricus and Streptococcus thermophilus) and probiotics (Lactobacillus acidophilus, Lactobacillus casei, and Lactobacillus reuteri) during fermentation and storage (35 d at 5°C), as well as sensory preference among them. Decreases in pH (0.17 to 0.50 units) and increases in titratable acidity (0.09 to 0.29%) were observed during storage. Only the yogurt with S. thermophilus, L. delbrueckii ssp. bulgaricus, and L. reuteri differed in firmness. No differences in adhesiveness were determined among the tested yogurts, fermented milks, and the control. Syneresis was in the range of 45 to 58%. No changes in color during storage were observed and no color differences were detected among the evaluated fermented milk products. Counts of S. thermophilus decreased from 1.8 to 3.5 log during storage. Counts of L. delbrueckii ssp. bulgaricus also decreased in probiotic yogurts and varied from 30 to 50% of initial population. Probiotic bacteria also lost viability throughout storage, although the 3 probiotic fermented milks maintained counts ≥ 10(7)cfu/mL for 3 wk. Probiotic bacteria had variable viability in yogurts, maintaining counts of L. acidophilus ≥ 10(7) cfu/mL for 35 d, of L. casei for 7d, and of L. reuteri for 14 d. We found no significant sensory preference among the 6 probiotic yogurts and fermented milks or the control. However, the yogurt and fermented milk made with L. casei were better accepted. This

  14. A new facile route for synthesizing of graphene oxide using mixture of sulfuric-nitric-phosphoric acids as intercalating agent

    NASA Astrophysics Data System (ADS)

    Panwar, Vinay; Chattree, Ananya; Pal, Kaushik

    2015-09-01

    In this work, graphene oxide (GO) has been prepared through three different processes namely, eco-friendly Hummers method, modification in improved Hummers method and a new approach. This new approach has been designed by changing some processing parameters and intercalating agent for significant reduction in processing time and to improve the quantity of GO in comparison to the other two methods. This has been achieved through better oxidization of graphite using nitric-sulfuric acid (HNO3-H2SO4) as intercalating agent. X-ray diffraction (XRD), Field Emission Scanning Electron Microscopy (FESEM), Energy-dispersive X-ray spectroscopy (EDX), Raman spectroscopy, Atomic Force Microscopy (AFM), X-ray photoelectron spectroscopy (XPS), UV-visible spectroscopy, and Thermogravimetric analysis (TGA) are used to characterize the GO prepared through different processes. These characterizations have confirmed an improved exfoliation of graphite, using addition of HNO3 in intercalating agent, in a short processing time and bring on higher yield of GO via this new process.

  15. The crosslinking of polysaccharides with polyamines and dextran-polyallylamine antibacterial hydrogels.

    PubMed

    O'Connor, Naphtali A; Abugharbieh, Ahmad; Yasmeen, Farzana; Buabeng, Emmanuel; Mathew, Steve; Samaroo, Diana; Cheng, Hai-Ping

    2015-01-01

    A facile modular approach to rapidly prepare pH-responsive hydrogels by crosslinking polysaccharides with polyamines is demonstrated. Hydrogels are prepared by first reacting the less reactive polysaccharides with the cross-linker epichlorohydrin and completed by the addition of polyamines. The crosslinking of polysaccharides with polyamines provides a facile method for incorporating functionality into polysaccharide based hydrogels. This process is demonstrated with the polysaccharides dextran, pullulan and carboxymethyl cellulose and with the polyamines polyallylamine and polyethylene imine. The hydrogels were characterized by FTIR and swelling studies, which showed pH-dependent swelling due to the presence of the polyamine. The hydrogels can also be tailored by varying the mass ratio between the polysaccharide and polyamine. Absorption studies of organic analytes showed the polyamine content affecting the uptake of a charged substrate (methylene blue) and no effect on a neutral substrate (6-methyl coumarin). This synthetic method was also used to prepare hydrogels with antibacterial activity against E. coli and S. aureus by utilizing an amphiphilic polyallylamine.

  16. Polyamines directly promote antizyme-mediated degradation of ornithine decarboxylase by the proteasome

    PubMed Central

    Beenukumar, R. R.; Gödderz, Daniela; Palanimurugan, R.; Dohmen, R. J.

    2015-01-01

    Ornithine decarboxylase (ODC), a ubiquitin-independent substrate of the proteasome, is a homodimeric protein with a rate-limiting function in polyamine biosynthesis. Polyamines regulate ODC levels by a feedback mechanism mediated by ODC antizyme (OAZ). Higher cellular polyamine levels trigger the synthesis of OAZ and also inhibit its ubiquitin-dependent proteasomal degradation. OAZ binds ODC monomers and targets them to the proteasome. Here, we report that polyamines, aside from their role in the control of OAZ synthesis and stability, directly enhance OAZ-mediated ODC degradation by the proteasome. Using a stable mutant of OAZ, we show that polyamines promote ODC degradation in Saccharomyces cerevisiae cells even when OAZ levels are not changed. Furthermore, polyamines stimulated the in vitro degradation of ODC by the proteasome in a reconstituted system using purified components. In these assays, spermine shows a greater effect than spermidine. By contrast, polyamines do not have any stimulatory effect on the degradation of ubiquitin-dependent substrates. PMID:28357293

  17. Arabidopsis thaliana polyamine content is modified by the interaction with different Trichoderma species.

    PubMed

    Salazar-Badillo, Fatima Berenice; Sánchez-Rangel, Diana; Becerra-Flora, Alicia; López-Gómez, Miguel; Nieto-Jacobo, Fernanda; Mendoza-Mendoza, Artemio; Jiménez-Bremont, Juan Francisco

    2015-10-01

    Plants are associated with a wide range of microorganisms throughout their life cycle, and some interactions result on plant benefits. Trichoderma species are plant beneficial fungi that enhance plant growth and development, contribute to plant nutrition and induce defense responses. Nevertheless, the molecules involved in these beneficial effects still need to be identify. Polyamines are ubiquitous molecules implicated in plant growth and development, and in the establishment of plant microbe interactions. In this study, we assessed the polyamine profile in Arabidopsis plants during the interaction with Trichoderma virens and Trichoderma atroviride, using a system that allows direct plant-fungal contact or avoids their physical interaction (split system). The plantlets that grew in the split system exhibited higher biomass than the ones in direct contact with Trichoderma species. After 3 days of interaction, a significant decrease in Arabidopsis polyamine levels was observed in both systems (direct contact and split). After 5 days of interaction polyamine levels were increased. The highest levels were observed with T. atroviride (split system), and with T. virens (direct contact). The expression levels of Arabidopsis ADC1 and ADC2 genes during the interaction with the fungi were also assessed. We observed a time dependent regulation of ADC1 and ADC2 genes, which correlates with polyamine levels. Our data show an evident change in polyamine profile during Arabidopsis - Trichoderma interaction, accompanied by evident alterations in plant root architecture. Polyamines could be involved in the changes undergone by plant during the interaction with this beneficial fungus.

  18. Polyamine inhibitors for treatment of feline oral squamous cell carcinoma: a proof-of-concept study.

    PubMed

    Lewis, John R; O'Brien, Thomas G; Skorupski, Katherine A; Krick, Erika L; Reiter, Alexander M; Jennings, Michael W; Jurney, Carrie H; Shofer, F S

    2013-01-01

    This study assessed proof-of-concept for use of polyamine inhibitor 2-diluoromethylornithine (DFMO) as a treatment for oral squamous cell carcinoma (SCC) in client-owned cats. Polyamine levels in tumor tissue and normal oral mucosa were quantified before and after treatment. DFMO was administered orally to 14 client-owned cats with histologically confirmed oral SCC. Patients were monitored for gastrointestinal, dermatologic, auditory, hematological, and biochemical abnormalities. Total polyamine levels in tumor tissue decreased after treatment, as did the specific polyamine putrescine in both tumor tissue and normal mucosa. Ototoxicity was observed in 5 of 6 cats receiving pre- and post-treatment brainstem auditory evoked potential tests. Subclinical thrombocytopenia was observed in 6 of 14 cats. One cat showed mild post-anesthetic tremors that resolved without treatment. Oral administration of DFMO at doses used in this study resulted in significantly decreased tumor polyamine levels without life-threatening clinical or hematological toxicities. Further studies are warranted to explore pathophysiology of polyamine biochemistry and use of polyamine inhibitors in treatment of cats with oral SCC.

  19. Upper critical solution temperature behavior of cinnamic acid and polyethyleneimine mixture and its effect on temperature-dependent release of liposome.

    PubMed

    Guo, Huangying; Kim, Jin-Chul

    2015-10-15

    The mixture of polyethyleneimine (PEI) and cinnamic acid (CA) in HEPES buffer (pH 7.0) exhibited an upper critical solution temperature in the temperature range of 20-50 °C. CA would be electrostatically conjugated with PEI and the PEI-CA conjugate is thought to act as a thermo-sensitive polymer. On the optical microscope image of PEI/CA mixture, microparticles were found at 25 °C, disappeared when heated to 50 °C, and formed again upon cooling to 25 °C. PEI-CA conjugate was immobilized on the surface of egg phosphatidylcholine (EPC) liposome by adding PEI to the suspension of liposome incorporating CA. The size and the zeta potential of the liposome markedly increased by cooling the liposomal suspension from 50 °C to 20 °C. This could be ascribed to the cooling-induced self-assembling property of PEI-CA conjugate. The release profile of Rhodamine B base from liposome incorporating CA with PEI was investigated while the liposome suspension of 50 °C was exposed to the release medium of 20 °C, 30 °C, 40 °C and 50 °C. The release degree was higher at a lower temperature. When exposed to a lower temperature (20 °C, 30 °C, 40 °C), PEI-CA could be self-assembled and change its configuration on the surface of liposome, promoting the release from the liposome.

  20. Production of lactic acid from the mixture of softwood pre-hydrolysate and paper mill sludge by simultaneous saccharification and fermentation.

    PubMed

    Shi, Suan; Kang, Li; Lee, Y Y

    2015-03-01

    Paper mill sludge is a solid waste material composed of pulp residues and ash generated from pulping and paper making process. The carbohydrate portion of the sludges from Kraft/Recycle paper mill has chemical and physical characteristics similar to those of commercial wood pulp. Because of its high carbohydrate content and well-dispersed structure, the sludge can be biologically converted to value-added products without pretreatment. In bioconversion of solid feedstock such as paper mill sludge, a certain amount of water must be present to attain fluidity. In this study, hemicellulose pre-hydrolysate, in place of water, was added to the sludge to increase the concentration of the final product. Pre-hydrolysate was obtained by hot-water treatment of pine wood in which the total sugar concentration reached 4 wt.%. The mixture was processed by simultaneous saccharification and fermentation (SSF) using enzymes (cellulase and pectinase) and Lactobacillus rhamnosus (ATCC-10863). Pectinase was added to hydrolyze mannose oligomers in the pre-hydrolysate to monomers. During the SSF of the mixture, calcium carbonate in the paper sludge acted as a buffer, yielding calcium lactate as the final product. External pH control was unnecessary due to the buffer action of calcium carbonate that maintained the pH near optimum for the SSF. The lactic acid yield in the range of 80-90 % of the theoretical maximum was obtained. Use of the mixed feed of pre-hydrolysate and pulp mill sludges in the SSF raised the product concentration to 60 g of lactate/L.

  1. Radioprotection of Human Cell Nuclear DNA by Polyamines: Radiosensitivity of Chromatin is Influenced by Tightly Bound Spermine

    NASA Technical Reports Server (NTRS)

    Warters, Raymond L.; Newton, Gerald L.; Olive, Peggy L.; Fahey, Robert C.

    1999-01-01

    The polyamines putrescine (PUT) and spermine (SPM) were examined for their ability to protect human cell Deoxyribonucleic Acid (DNA) against the formation of radiation-induced double-strand breaks (DSBs). As observed previously, under conditions where polyamines were shown to be almost completely absent, association with nuclear matrix protein into a nucleoid, and organization into chromatin structure, protected DNA from induction of DSBs by factors of 4.5 and 95, respectively. At concentrations below 1 mM, PUT or SPM provided equivalent levels of protection to deproteinized nuclear DNA, consistent with their capacity to scavenge radiation-induced radicals. At constant ionic strength, 5 mM SPM protected deproteinized DNA and nucleoid DNA and DNA in nuclear chromatin by factors of 100 and 26, respectively. At 5 mM, SPM provided 15 times greater protection of deproteinized DNA than did PUT. Under physiologically relevant conditions, 5 mM SPM protected DNA in the intact nucleus from the induction of DSBs by a factor of 2 relative to DNA in the absence of SPM. Studies of SPM binding during cellular fractionation revealed that a significant fraction of the cellular SPM is tightly bound in the nucleus but can be removed by extended washing. Thus the association of SPM with nuclear chromatin appears to be a significant contributor to the resistance of the cell's DNA to the induction of DSBs.

  2. Effect of inhibitors of polyamine biosynthesis on gibberellin-induced internode growth in light-grown dwarf peas

    NASA Technical Reports Server (NTRS)

    Kaur-Sawhney, R.; Dai, Y. R.; Galston, A. W.

    1986-01-01

    When gibberellic acid (GA3) is sprayed on 9-day-old light-brown dwarf Progress pea (Pisum sativum) seedlings, arginine decarboxylase (ADC; EC 4.1.1.9) activity increases within 3 h and peaks at about 9 h after GA3 application. This is followed by a second lower peak at about 30 h; both peaks were higher than the corresponding peaks in the controls. In contrast, no appreciable effect of GA3 on internode length was observed until about 12 h, after which time a dramatic increase in growth rate occurred and persisted for about 12 h. Specific (DL-alpha-difluoromethylarginine) and non-specific (D-arginine and L-canavanine) inhibitors of ADC strongly inhibited ADC activity and to a lesser extent internode growth. The inhibition was reversed only slightly by the addition of polyamines. Actinomycin D and cycloheximide inhibited the rise in ADC activity induced by GA3. The half-life of the enzyme was increased by GA3 treatment. The results suggest that part of the GA3-induced increase in internode growth may result from enhanced polyamine biosynthesis through the ADC pathway. Furthermore, the GA3 induced increase in ADC activity probably requires de novo synthesis of both RNA and protein.

  3. Dissecting Rice Polyamine Metabolism under Controlled Long-Term Drought Stress

    PubMed Central

    Do, Phuc Thi; Degenkolbe, Thomas; Erban, Alexander; Heyer, Arnd G.; Kopka, Joachim; Köhl, Karin I.; Hincha, Dirk K.; Zuther, Ellen

    2013-01-01

    A selection of 21 rice cultivars (Oryza sativa L. ssp. indica and japonica) was characterized under moderate long-term drought stress by comprehensive physiological analyses and determination of the contents of polyamines and selected metabolites directly related to polyamine metabolism. To investigate the potential regulation of polyamine biosynthesis at the transcriptional level, the expression of 21 genes encoding enzymes involved in these pathways were analyzed by qRT-PCR. Analysis of the genomic loci revealed that 11 of these genes were located in drought-related QTL regions, in agreement with a proposed role of polyamine metabolism in rice drought tolerance. The cultivars differed widely in their drought tolerance and parameters such as biomass and photosynthetic quantum yield were significantly affected by drought treatment. Under optimal irrigation free putrescine was the predominant polyamine followed by free spermidine and spermine. When exposed to drought putrescine levels decreased markedly and spermine became predominant in all cultivars. There were no correlations between polyamine contents and drought tolerance. GC-MS analysis revealed drought-induced changes of the levels of ornithine/arginine (substrate), substrates of polyamine synthesis, proline, product of a competing pathway and GABA, a potential degradation product. Gene expression analysis indicated that ADC-dependent polyamine biosynthesis responded much more strongly to drought than the ODC-dependent pathway. Nevertheless the fold change in transcript abundance of ODC1 under drought stress was linearly correlated with the drought tolerance of the cultivars. Combining metabolite and gene expression data, we propose a model of the coordinate adjustment of polyamine biosynthesis for the accumulation of spermine under drought conditions. PMID:23577102

  4. Activation of Dbl restores migration in polyamine-depleted intestinal epithelial cells via Rho-GTPases

    PubMed Central

    Bavaria, Mitulkumar N.; Bhattacharya, Sujoy; Johnson, Leonard R.

    2011-01-01

    Integrin binding to the extracellular matrix (ECM) activated Rho GTPases, Src, and focal adhesion kinase in intestinal epithelial cells (IEC)-6. Polyamine depletion inhibited activities of Rac1, RhoA, and Cdc42 and thereby migration. However, constitutively active (CA) Rac1 expression abolished the inhibitory effect of polyamine depletion, indicating that polyamines are involved in a process upstream of Rac1. In the present study, we examined the role of polyamines in the regulation of the guanine nucleotide exchange factor, diffuse B-cell lymphoma (Dbl), for Rho GTPases. Polyamine depletion decreased the level as well as the activation of Dbl protein. Dbl knockdown by siRNA altered cytoskeletal structure and decreased Rac1 activity and migration. Cells expressing CA-Dbl increased migration, Rac1 activity, and proliferation. CA-Dbl restored migration in polyamine-depleted cells by activating RhoA, Rac1, and Cdc42. CA-Dbl caused extensive reorganization of the F-actin cortex into stress fibers. Inhibition of Rac1 by NSC23766 significantly decreased migration of vector-transfected cells and CA-Dbl-transfected cells. However, the inhibition of migration was significantly higher in the vector-transfected cells compared with that seen in the CA-Dbl-transfected cells. Dbl localized in the perinuclear region in polyamine-depleted cells, whereas it localized with the stress fibers in control cells. CA-Dbl localized with stress fibers in both the control and polyamine-depleted cells. These results suggest that polyamines regulate the activation of Dbl, a membrane-proximal process upstream of Rac1. PMID:21372162

  5. Catalytic and mechanistic studies into the epoxidation of styrenes using manganese complexes of structurally similar polyamine ligands.

    PubMed

    Ilyashenko, Gennadiy; De Faveri, Giorgio; Follier, Thomas; Al-Safadi, Rawan; Motevalli, Majid; Watkinson, Michael

    2014-02-21

    Two structurally similar polyamine ligands (7 and 8) have been prepared, which differ only by the presence of either a secondary or tertiary nitrogen donor within their N5 donor set. The ligands, in combination with iron and manganese salts, have been screened for their efficacy as catalysts for the epoxidation of styrene, using both hydrogen peroxide and peracetic acid as oxidants. Clear differences in activity between the two systems were observed, with 7 proving most effective in the presence of MnSO4 with H2O2, whereas ligand 8 proved to be effective with Mn(OTf)2, MnCl2 and Mn(ClO4)2 using peracetic acid as the oxidant. A Hammett analysis of the initial rate kinetics of the optimal systems, combined with analysis by UV-vis spectroscopy, indicates that the small structural differences in the ligands elicit profound changes in the nature of the active species formed.

  6. Polyamine profile in ovine and caprine colostrum and milk.

    PubMed

    Galitsopoulou, Augustina; Michaelidou, Alexandra-Maria; Menexes, George; Alichanidis, Efstathios

    2015-04-15

    The objective of this study was to monitor the post-partum variation of polyamine content, in ovine and caprine milk, from indigenous Greek breeds. Twenty samples of ewe and 20 samples of goat colostrum and milk were collected at the 1st, 2nd, 3rd, 4th, 5th and 15th day post-partum. Putrescine, spermidine and spermine were measured as dansylated derivatives by high-performance liquid chromatography. Putrescine was the least concentrated of these substances in both milk types. Spermidine was the prevailing polyamine in caprine samples, reaching levels up to 4.41 μmol/l on the 3rd day post-partum. In ovine milk, the profile of the mean concentrations showed greater levels of spermine than spermidine, except for the 5th day post-partum. These data suggest that goat colostrum and ewe milk (15th day) could be considered as good natural sources for these bioactive growth factors, and may become useful raw materials for designing tailored dairy products for specific population groups.

  7. STABILIZATION OF PROTOPLASTS AND SPHEROPLASTS BY SPERMINE AND OTHER POLYAMINES

    PubMed Central

    Tabor, Celia W.

    1962-01-01

    Tabor, Celia W. (National Institute of Arthritis and Metabolic Diseases, Bethesda, Md.). Stabilization of protoplasts and spheroplasts by spermine and other polyamines. J. Bacteriol. 83:1101–1111. 1962.—Spermine (10−3m) or spermidine prevents lysis of lysozyme-produced protoplasts of Escherichia coli W, E. coli B, and Micrococcus lysodeikticus in hypotonic media. Spheroplasts prepared by the action of penicillin are also stabilized by these concentrations of spermine and spermidine, but the protection is not as complete. Streptomycin, polylysine, and Ca++ are also effective or partially effective stabilizers, but 1,4-diaminobutane, 1,5-diaminopentane, ornithine, Mg++, and monovalent cations have no protective action at 10−3m concentration, and only a slight effect at higher concentrations. The osmotic stability conferred on protoplasts by spermine is irreversible. However, the protective effect of polyamines against lysis is not accompanied by restoration of viability to lysozyme protoplasts. There is a marked reduction in the loss of ultra-violet-absorbing material from the protoplasts to the medium when 10−3m spermine is present. PMID:16561942

  8. Chlorella viruses contain genes encoding a complete polyamine biosynthetic pathway

    PubMed Central

    Baumann, Sascha; Sander, Adrianne; Gurnon, James R.; Yanai-Balser, Giane; VanEtten, James L.; Piotrowski, Markus

    2007-01-01

    Two genes encoding the putative polyamine biosynthetic enzymes agmatine iminohydrolase (AIH) and N-carbamoylputrescine amidohydrolase (CPA) were cloned from the chloroviruses PBCV-1, NY-2A and MT325. They were expressed in Escherichia coli to form C-terminal (His)6-tagged proteins and the recombinant proteins were purified by Ni2+- binding affinity chromatography. The biochemical properties of the two enzymes are similar to AIH and CPA enzymes from Arabidopsis thaliana and Pseudomonas aeruginosa. Together with the previously known virus genes encoding ornithine/arginine decarboxlyase (ODC/ADC) and homospermidine synthase, the chloroviruses have genes that encode a complete set of functional enzymes that synthesize the rare polyamine homospermidine from arginine via agmatine, N-carbamoylputrescine and putrescine. The PBCV-1 aih and cpa genes are expressed early during virus infection together with the odc/adc gene, suggesting that biosynthesis of putrescine is important in early stages of viral replication. The aih and cpa genes are widespread in the chlorella viruses. PMID:17101165

  9. Posttranslational protein modification by polyamines in intact and regenerating nerves.

    PubMed

    Chakraborty, G; Leach, T; Zanakis, M F; Sturman, J A; Ingoglia, N A

    1987-03-01

    A 150,000-g supernatant from axoplasm of the giant axon of the stellate nerve of the squid and from rat sciatic and goldfish optic nerves was found to be able to incorporate covalently [3H]putrescine and [3H]spermidine into an exogenous protein (N,N'-dimethylcasein). Incorporation of radioactivity was inhibited by CuSO4, a specific inhibitor of transglutaminases, the enzymes mediating these reactions in other tissues. Analysis of pH and temperature range and enzyme kinetics displayed characteristics predicted for transglutaminase-mediated reactions. Transglutaminase activity increased during regeneration of both vertebrate nerves, but greater activity was found in segments of nerve containing no intact axons than in either intact segments or in segments containing regenerating axons. Polyacrylamide gel electrophoresis of endogenous modified proteins (in the absence of N,N'-dimethylcasein) showed labeling of 18-, 46- and 200-kilodalton proteins by both [3H]putrescine and [3H]spermidine. Analysis of the protein-bound radioactivity from intact and regenerating rat sciatic nerves demonstrated it to be predominantly in the form of the parent radioactive polyamine. These experiments demonstrate the covalent modification of proteins by polyamines at low levels in squid axoplasm and at relatively higher levels in rat sciatic and goldfish optic nerves. In the latter two cases, the activity of these modification reactions may be due in part to the modification of axonal proteins, but the majority of the activity occurs in nonneuronal cells of the nerve.

  10. A Polyamine Metabolon Involving Aminopropyl Transferase Complexes in Arabidopsis

    PubMed Central

    Panicot, Mireia; Minguet, Eugenio G.; Ferrando, Alejandro; Alcázar, Rubén; Blázquez, Miguel A.; Carbonell, Juan; Altabella, Teresa; Koncz, Csaba; Tiburcio, Antonio F.

    2002-01-01

    The conversion of putrescine to spermidine in the biosynthetic pathway of plant polyamines is catalyzed by two closely related spermidine synthases, SPDS1 and SPDS2, in Arabidopsis. In the yeast two-hybrid system, SPDS2 was found to interact with SPDS1 and a novel protein, SPMS (spermine synthase), which is homologous with SPDS2 and SPDS1. SPMS interacts with both SPDS1 and SPDS2 in yeast and in vitro. Unlike SPDS1 and SPDS2, SPMS failed to suppress the speΔ3 deficiency of spermidine synthase in yeast. However, SPMS was able to complement the speΔ4 spermine deficiency in yeast, indicating that SPMS is a novel spermine synthase. The SPDS and SPMS proteins showed no homodimerization but formed heterodimers in vitro. Pairwise coexpression of hemagglutinin- and c-Myc epitope–labeled proteins in Arabidopsis cells confirmed the existence of coimmunoprecipitating SPDS1-SPDS2 and SDPS2-SPMS heterodimers in vivo. The epitope-labeled SPDS and SPMS proteins copurified with protein complexes ranging in size from 650 to 750 kD. Our data demonstrate the existence of a metabolon involving at least the last two steps of polyamine biosynthesis in Arabidopsis. PMID:12368503

  11. Surface modification of an epoxy resin with polyamines and polydopamine: Adhesion toward electroless deposited copper

    NASA Astrophysics Data System (ADS)

    Schaubroeck, David; Mader, Lothar; Dubruel, Peter; Vanfleteren, Jan

    2015-10-01

    In this paper the influence of the epoxy roughness, surface modifications and ELD (electroless copper deposition) temperatures on the adhesive strength of the copper is studied. Good adhesion at low roughness values is targeted due to their applicability in high density electronic circuits. Roughened epoxy surfaces are modified with adsorbed polyamines, polydopamine and polyamines grafted to polydopamine. Next the, adhesive strength of ELD copper is determined with peel strength measurements and the interphases are examined with SEM (scanning electron microscopy). Polydopamine and polyamines grafted to polydopamine can lead to increased adhesive strength at lower roughness values compared to the non-modified samples at specific plating temperatures.

  12. Raman study of the effects of polyamines on DNA:spermine and histamine

    NASA Astrophysics Data System (ADS)

    Ruiz-Chica, J.; Medina, M. A.; Sánchez-Jiménez, F.; Ramírez, F. J.

    1999-05-01

    Fourier transform Raman spectroscopy was used to investigate the interaction of spermine and histamine with calf-thymus DNA. Polyamine-DNA solutions at different polyamine concentrations ranging from 5 mM to 75 mM were prepared. For spermine, solutions no higher than 15 mM were prepared because this molecule induces condensation and aggregation on DNA at upper concentrations. Possible sites of bindings for polyamine-DNA complexes were discussed on the basis of the spectral changes observed with respect to the Raman spectra of DNA. The results seem to indicate that one spermine molecule induces on DNA a similar effect to two or more histamine molecules.

  13. Chlorophyll degradation and inhibition of polyamine biosynthesis in the lichen Xanthoria parietina under nitrogen stress.

    PubMed

    Munzi, Silvana; Pirintsos, Stergios Arg; Loppi, Stefano

    2009-02-01

    This study investigated if some nitrogen (N) compounds commonly used as fertilizers (KNO3, NH4NO3, (NH4)2SO4) cause chlorophyll degradation in the N-tolerant lichen Xanthoria parietina and if polyamines are responsible for the N-tolerance of this species. The results showed that N excess does not cause chlorophyll degradation and suggested the absence of kinetics in the mode of action of the N compounds tested. External supply of inhibitors of polyamine biosynthesis prior to N treatments did not cause any change in the response of chlorophyll integrity, suggesting that at least chlorophyll integrity is not controlled by polyamines.

  14. The natural polyamine spermine functions directly as a free radical scavenger

    PubMed Central

    Ha, Hyo Chol; Sirisoma, Nilantha S.; Kuppusamy, Periannan; Zweier, Jay L.; Woster, Patrick M.; Casero, Robert A.

    1998-01-01

    The polyamines are small organic cations that are absolutely required for eukaryotic cell growth. Although their growth requirements are well established, the molecular functions of the polyamines are ill-defined. Oxidative damage to DNA by reactive oxygen species is a continual problem that cells must guard against to survive. The polyamine spermine, which is normally found in millimolar concentrations in the nucleus, is shown here to function directly as a free radical scavenger, and adducts formed as a result of this function are identified. These data suggest that spermine is a major natural intracellular compound capable of protecting DNA from free radical attack. PMID:9736703

  15. Interaction of Brassinosteroids and Polyamines Enhances Copper Stress Tolerance in Raphanus Sativus

    PubMed Central

    Choudhary, Sikander Pal; Yu, Jing-Quan; Tran, Lam-Son Phan

    2012-01-01

    Brassinosteroids (BRs) and polyamines (PAs) regulate various responses to abiotic stress, but their involvement in the regulation of copper (Cu) homeostasis in plants exposed to toxic levels of Cu is poorly understood. This study provides an analysis of the effects of exogenously applied BRs and PAs on radish (Raphanus sativus) plants exposed to toxic concentrations of Cu. The interaction of 24-epibrassinolide (EBR, an active BR) and spermidine (Spd, an active PA) on gene expression and the physiology of radish plants resulted in enhanced tolerance to Cu stress. Results indicated that the combined application of EBR and Spd modulated the expression of genes encoding PA enzymes and genes that impact the metabolism of indole-3-acetic acid (IAA) and abscisic acid (ABA) resulting in enhanced Cu stress tolerance. Altered expression of genes implicated in Cu homeostasis appeared to be the main effect of EBR and Spd leading to Cu stress alleviation in radish. Ion leakage, in vivo imaging of H2O2, comet assay, and improved tolerance of Cu-sensitive yeast strains provided further evidence for the ability of EBR and Spd to improve Cu tolerance significantly. The study indicates that co-application of EBR and Spd is an effective approach for Cu detoxification and the maintenance of Cu homeostasis in plants. Therefore, the use of these compounds in agricultural production systems should be explored. PMID:22915739

  16. Interaction of brassinosteroids and polyamines enhances copper stress tolerance in raphanus sativus.

    PubMed

    Choudhary, Sikander Pal; Oral, H Volkan; Bhardwaj, Renu; Yu, Jing-Quan; Tran, Lam-Son Phan

    2012-09-01

    Brassinosteroids (BRs) and polyamines (PAs) regulate various responses to abiotic stress, but their involvement in the regulation of copper (Cu) homeostasis in plants exposed to toxic levels of Cu is poorly understood. This study provides an analysis of the effects of exogenously applied BRs and PAs on radish (Raphanus sativus) plants exposed to toxic concentrations of Cu. The interaction of 24-epibrassinolide (EBR, an active BR) and spermidine (Spd, an active PA) on gene expression and the physiology of radish plants resulted in enhanced tolerance to Cu stress. Results indicated that the combined application of EBR and Spd modulated the expression of genes encoding PA enzymes and genes that impact the metabolism of indole-3-acetic acid (IAA) and abscisic acid (ABA) resulting in enhanced Cu stress tolerance. Altered expression of genes implicated in Cu homeostasis appeared to be the main effect of EBR and Spd leading to Cu stress alleviation in radish. Ion leakage, in vivo imaging of H(2)O(2), comet assay, and improved tolerance of Cu-sensitive yeast strains provided further evidence for the ability of EBR and Spd to improve Cu tolerance significantly. The study indicates that co-application of EBR and Spd is an effective approach for Cu detoxification and the maintenance of Cu homeostasis in plants. Therefore, the use of these compounds in agricultural production systems should be explored.

  17. Polyamine levels as related to growth, differentiation and senescence in protoplast-derived cultures of Vigna aconitifolia and Avena sativa

    NASA Technical Reports Server (NTRS)

    Kaur Sawhney, R.; Shekhawat, N. S.; Galston, A. W.

    1985-01-01

    We have previously reported that aseptically cultured mesophyll protoplasts of Vigna divide rapidly and regenerate into complete plants, while mesophyll protoplasts of Avena divide only sporadically and senesce rapidly after isolation. We measured polyamine titers in such cultures of Vigna and Avena, to study possible correlations between polyamines and cellular behavior. We also deliberately altered polyamine titer by the use of selective inhibitors of polyamine biosynthesis, noting the effects on internal polyamine titer, cell division activity and regenerative events. In Vigna cultures, levels of free and bound putrescine and spermidine increased dramatically as cell division and differentiation progressed. The increase in bound polyamines was largest in embryoid-forming callus tissue while free polyamine titer was highest in root-forming callus. In Avena cultures, the levels of total polyamines decreased as the protoplast senesced. The presence of the inhibitors alpha-difluoromethyl-arginine (specific inhibitor of arginine decarboxylase), alpha-difluoromethylornithine (specific inhibitor of ornithine decarboxylase) and dicyclohexylamine (inhibitor of spermidine synthase) reduced cell division and organogenesis in Vigna cultures. Addition of low concentration of polyamines to such cultures containing inhibitors or removal of inhibitors from the culture medium restored the progress of growth and differentiation with concomitant increase in polyamine levels.

  18. Methanothermal reduction of mixtures of PbSO4 and PbO2 to synthesize ultrafine α-PbO powders for lead acid batteries

    NASA Astrophysics Data System (ADS)

    Gao, Pengran; Liu, Yi; Lv, Weixin; Zhang, Rui; Liu, Wei; Bu, Xianfu; Li, Guanghua; Lei, Lixu

    2014-11-01

    Three artificial mixtures of PbSO4 and PbO2 as well as the active materials obtained directly from the positive plates of spent batteries have been solvothermally treated in methanol at 140 °C for 24 h, which produce mainly PbO·PbSO4. The PbO·PbSO4 can be easily desulphated with ammonium carbonate to produce PbCO3, which can be calcined to form α-PbO to be used as positive active material of lead acid batteries. The α-PbO powders are irregular particles and highly electrochemically active, which discharges around 165 mAh g-1 at 5 mA g-1, 80 mAh g-1 at 200 mA g-1 and 60 mAh g-1 at 400 mA g-1 with excellent cyclic stability in 50 cycles. SEM investigations show that the as-formed PbO·PbSO4 may inherit and enhance the morphological characteristics of PbSO4, and carbonation of PbO·PbSO4 does not destroy the rod-like characteristics. For the active material from the positive plates of spent lead acid batteries, the discharge capacities are 170 mAh g-1 at the current density of 5 mA g-1, and 60 mAh g-1 at 400 mA g-1, which is also similar. In 50 cycles, its capacity loss is only 5%.

  19. Lack of protective effect of D-003, a mixture of high-molecular-weight primary acids from sugar cane wax, on liver damage induced by galactosamine in rats.

    PubMed

    Noa, Miriam; Mendoza, Sarahí; Mas, Rosa; Mendoza, Nilda

    2005-01-01

    D-003 is a mixture of very-high-molecular-weight aliphatic primary acids purified from sugar cane wax, wherein octacosanoic acid is the most abundant. Experimental and clinical studies have shown that D-003 lowers cholesterol and prevents plasma lipoprotein peroxidation (LP). D-003 has protected against the histological changes characteristic of CCl4- and paracetamol-induced hepatic injury in rats, in which LP plays a pivotal role for explaining the resulting hepatotoxicity. Galactosamine induces hepatotoxicity associated with depressed RNA and protein synthesis, not with LP. The aim of this study was to evaluate whether D-003 could prevent hepatoxicity induced by mechanisms others than increased LP. We investigated the effects on galactosamine hepatotoxicity in rats distributed into five groups: a negative control group, a positive control group, and three groups treated with galactosamine and D-003 (5, 25, and 100 mg/kg). To induce liver damage, galactosamine (800 mg/kg) was injected intraperitoneally 30 minutes after dosing with vehicle or D-003. Twenty-four hours later, rats were sacrificed, and livers were immediately removed for histopathological studies. Livers from positive controls showed the characteristic pattern of galactosamine-induced damage. Galactosamine significantly reduced the percentage of normal hepatocytes, increasing both necrotic or lipid-rich hepatocytes compared with negative controls. D-003, however, did not increase the percentage of normal hepatocytes compared with positive controls, indicating that treatment was not effective for preventing the hepatic injury induced with galactosamine. Likewise, D-003 failed to change the content of necrotic and lipid-rich hepatocytes relative to positive controls. It is concluded that D-003 did not protect against the histological changes of galactosamine-induced hepatotoxicity.

  20. Lipase-catalyzed acidolysis of palm mid fraction oil with palmitic and stearic Fatty Acid mixture for production of cocoa butter equivalent.

    PubMed

    Mohamed, Ibrahim O

    2013-10-01

    Cocoa butter equivalent (CBE) was prepared by enzymatic acidolysis reaction of substrate consisting of refined palm mid fraction oil and palmitic-stearic fatty acid mixture. The reactions were performed in a batch reactor at a temperature of 60 °C in an orbital shaker operated at 160 RPM. Different mass ratios of substrates were explored, and the composition of the five major triacylglycerols (TAGs) of the structured lipids was identified and quantified using cocoa butter certified reference material IRMM-801. The reaction resulted in production of cocoa butter equivalent with the TAGs' composition (1,3-dipalmitoyl-2-oleoyl-glycerol 30.7%, 1-palmitoyl-2-oleoyl-3-stearoyl-rac-glycerol 40.1%, 1-palmitoy-2,3- dioleoyl glycerol 9.0%, 1,3-distearoyl-2-oleoyl-glycerol 14.5 %, and 1-stearoyl-2,3-dioleoyl glycerol 5.7%) and with onset melting temperature of 31.6 °C and peak temperature of 40.4 °C which are close to those of cocoa butter. The proposed kinetics model for the acidolysis reaction presented the experimental data very well. The results of this research showed that palm mid fraction oil TAGs could be restructured to produce value added product such as CBE.

  1. Selection of background electrolyte for CZE analysis by a chemometric approach. Part I. Separation of a mixture of acidic non-steroidal anti-inflammatory drugs.

    PubMed

    Furlanetto, Sandra; Lanteri, Silvia; Orlandini, Serena; Gotti, Roberto; Giannini, Iacopo; Pinzauti, Sergio

    2007-03-12

    This paper is the first part of the presentation of a chemometric approach for the rapid selection of a suitable background electrolyte (BGE) in CZE analysis of small drug molecules. The strategy is based on principal component analysis and experimental design. In this first section, the approach is applied to the analysis of a mixture of six arylpropionic anti-inflammatory drugs. Initially, 222 possible aqueous background electrolytes (objects) were characterized using as descriptors pH, conductivity, ionic strength and relative viscosity. In order to allow the dissociation of the acidic analytes, this original data set was reduced to 154 background electrolytes with pH values higher than or equal to 5. Principal component analysis made it possible to graphically represent the new set of objects, described by the four variables, in a two-dimensional space. Among these electrolytes, Kennard-Stone algorithm selected ten objects to be tested by CZE, covering homogeneously principal component space. CZE analyses were carried out with the selected electrolytes, and 0.1 M borax was identified as the most suitable one for the specified application. Finally, the characteristics of the analysis were finely tuned by means of a response surface study, which allowed the best conditions to be determined: borax concentration, 0.09 M; methanol, 6% (v/v); temperature, 24 degrees C, voltage, 20 kV. Applying these conditions, a baseline resolution among the six compounds was obtained in less than 10 min.

  2. Evaluation of tubular ceramic heat exchanger materials in acidic coal ash from coal-oil-mixture combustion. [Sialon; alumina; CVD, sintered, and siliconized SiC

    SciTech Connect

    Ferber, M.K.; Tennery, V.J.

    1981-12-01

    Tubes of five ceramic materials were exposed to the hot combustion gases from a coal-oil-mixture (COM) fuel in the Ceramic Recuperator Analysis Facility (CRAF) at about 1200/sup 0/C for about 500 h. Siliconized SiC, sintered ..cap alpha..-SiC, and chemically vapor deposited (CVD) SiC survived the long-term exposure with no major visible degradation. The alumina and sialon tubes were cracked extensively. Acidic coal slag deposited extensively on the upstream surface of all tubes. During cooldown, the slag did not strongly bond to any of the silicon carbide tubes, but a strong bond was developed with the alumina and sialon tubes. The silicon carbides corroded by a micropitting oxidation at the carbide-slag interface. The SiC and Si phases of siliconized SiC corroded at essentially the same rate. Exposure to hot coal slag increased the room-temperature helium permeability of all the SiC-based tubes. For KT and CVD SiC, both upstream and downstream sides exhibited expansion increases up to about 17% at 1000/sup 0/C. Sintered ..cap alpha..-SiC had much smaller increases. Al/sub 2/O/sub 3/ had an expansion increase of about 14% on the upstream side at 1000/sup 0/C but the downstream side was unchanged. 65 figures, 22 tables.

  3. Strong Acid Mixture and Sequential Geochemical Arsenic Extractions in Surface Sediments from the Santa Maria La Reforma Coastal Lagoon, Mexico: A Bioavailability Assessment.

    PubMed

    Rivera-Hernández, José R; Green-Ruiz, Carlos

    2016-02-01

    Thirty-three sediment samples were collected from the Santa Maria La Reforma coastal lagoon and digested by way of a strong acid mixture and sequential arsenic (As)-extraction method to determine the arsenic (As) content and bioavailability. The As content was determined by atomic fluorescence spectrometry. In addition, grain-size analyses were performed, and organic carbon, carbonate, and iron (Fe) and manganese (Mn) concentrations were determined. Fe and Mn determination was performed by atomic absorption spectroscopy. A Pearson correlation matrix and As enrichment factors were calculated. Sediment concentrations from Santa Maria La Reforma ranged from 3.6 to 25 µg As g(-1) with an average of 13.4 ± 7.6 µg As g(-1). The highest values were observed in the northern (Playa Colorada), north-central (Mocorito River discharge zone), and southern zones ("El Tule" agricultural drain). Most samples were classified as exhibiting no or minor As enrichment and were lower than the threshold effect level (TEL; 7.24 µg g(-1)) for biota (MacDonald et al. in Ecotoxicology 5:253-278, 1996). Low bioavailable As values (<3 %) were measured in the majority of the sediment. The highest As percentages were associated with the oxyhydroxide fraction (F5). The results indicate that As bioavailability is negligible.

  4. Optimization of strawberry disinfection by fogging of a mixture of peracetic acid and hydrogen peroxide based on microbial reduction, color and phytochemicals retention.

    PubMed

    Van de Velde, Franco; Vaccari, María Celia; Piagentini, Andrea Marcela; Pirovani, María Élida

    2016-09-01

    The fogging of strawberries using a environmentally friendly sanitizer mixture of peracetic acid (5%) and hydrogen peroxide (20%) was performed in a model chamber and modeled as a function of the concentration (3.4, 20.0, 60.0, 100.0 and 116.6 µL sanitizer L(-) (1) air chamber) and the treatment time (5.7, 15.0, 37.5, 60.0 and 69.3 min). The sanitizer fogging was adequate for reducing total mesophilic microbial and yeasts and moulds counts of fruits until seven days of storage at 2℃. However, sanitizer oxidant properties adversely affected the content of total anthocyanins, total phenolics, vitamin C, and antioxidant capacity to various degrees, with some deleterious changes in the fruits color, depending on the fogging conditions. A multiple numeric response optimization was developed based on 2.0 log microbiological reduction, maximum phytochemicals and antioxidant capacity retentions, with no changes in the fruits color, being the optimal fogging conditions achieved: 10.1 µL sanitizer L(-1) air chamber and 29.6 min. The fogging of strawberries at these conditions may represent a promising postharvest treatment option for extending their shelf-life without affecting their sensory quality and bioactive properties.

  5. A modified weighted mixture model for the interpretation of spatial and temporal changes in the microbial communities in drinking water reservoirs using compositional phospholipid fatty acid data.

    PubMed

    Stanimirova, I; Woznica, A; Plociniczak, T; Kwasniewski, M; Karczewski, J

    2016-11-01

    The aim of this work was to check whether a methodology based on the analysis of data that contain the entire phospholipid fatty acid, PLFA, compositions of water samples can be successfully used to interpret spatial and temporal changes in the microbial communities in water reservoirs. The proposed methodology consists of the construction of a modified weighted multivariate mixture model for the PLFA profiles of the water samples collected in a given monitoring campaign and the identification of latent PLFA components through a comparison with the known PLFA profiles of some cultivated or non-cultivated microbial communities. A 16S rDNA analysis of some of the selected water samples in the monitoring campaign was performed in order to verify the results of the PLFA analysis. The results showed that the proposed methodology can be useful for a dynamic and sensitive evaluation of changes in the microbial quality of water before and after flash flooding and can help in taking a decision regarding further risk assessment.

  6. Free polyamine content during algal bloom succession in the East China Sea in spring 2010

    NASA Astrophysics Data System (ADS)

    Liu, Yan; Zhao, Weihong; Li, Caiyan; Miao, Hui

    2017-01-01

    We measured the concentrations and distribution of major polyamines (spermine, putrescine and spermidine) in seawater during successive spring algal blooms in an area of frequent harmful blooms in the East China Sea. Spermine, putrescine, and spermidine concentrations were analyzed by high performance liquid chromatography and ranged from 1-64, 7-81, and 0-19 nmol/L. Spermine was present at the highest concentrations, followed by putrescine and spermidine. In late April, when a diatom bloom dominated by Skeletonema costatum dispersed, polyamine concentrations increased, presumably as a result of diatom decomposition. In early May, when a dinoflagellate bloom dominated by Prorocentrum donghaiense occurred, the polyamine concentration decreased from the level seen in late April. The abundant polyamines that decomposed and were released during the diatom bloom in late April may have promoted the growth of P. donghaiense, resulting in its dominance.

  7. Role of Polyamine Oxidase (PAOh1/SMO) in Human Breast Cancer

    DTIC Science & Technology

    2006-04-01

    Huang Y, Hacker A, Woster PM, Casero RA, and Davidson NE. Proc AACR. Page 1224, 2004 Publications: Spermine oxidase SMO(PAOh1), not N1...Hacker A, Zhang Z, Woster PM, Davidson NE, and Casero RA Jr. J Biol Chem, 280: 39843-41, 2005. Page 8 Presentations: The role of spermine oxidase...perspective of polyamine metabolism. Biochem J. 376: 1-14, 2003. 2. Huang Y, Pledgie A, Casero RA, and Davidson NE. Molecular mechanisms of polyamine