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Sample records for diamyl sulfoxide

  1. A Molecular Dynamics Study of Tributyl Phosphate and Diamyl Amyl Phosphonate Self-Aggregation in Dodecane and Octane.

    PubMed

    Servis, Michael J; Tormey, Caleb A; Wu, David T; Braley, Jenifer C

    2016-03-17

    A molecular dynamics model for tributyl phosphate (TBP) and diamyl amyl phosphonate (DAAP) is presented using the Generalized AMBER Force Field (GAFF) and the AM1-BCC method for calculated atomic charges with a modification to the phosphorus-containing dihedral parameters. The density and average molecular dipole in a neat liquid simulation, and dimerization in dodecane and octane diluents, compare favorably to experimental values. At low extractant concentration, investigation of the dimer structure reveals the offset "head-to-head" orientation as the predominant structure over a range of TBP and DAAP concentrations with a phosphoryl oxygen separation distance between dimerized extractants of 3-5.5 Å. At high extractant concentrations, a graph analysis of extractant aggregates was used to determine concentrations of each aggregate size and the average coordination number, which gives a measure of the linearity of the aggregates. For aggregates up to 7 extractant molecules, the mean free energy of association per molecule was found to be 0.55-0.59 and 0.72 kcal/mol for TBP and DAAP, respectively. In both diluents, TBP formed large aggregates more frequently than DAAP, and those aggregates were more nonlinear than their DAAP equivalents. This finding anticipates differences in aggregation chemistry between TBP and DAAP in PUREX extraction systems. PMID:26886767

  2. p-Chlorophenyl methyl sulfoxide

    Integrated Risk Information System (IRIS)

    p - Chlorophenyl methyl sulfoxide ; CASRN 934 - 73 - 6 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for

  3. Selenium and Methionine Sulfoxide Reduction.

    PubMed

    Gladyshev, Vadim N

    2014-10-01

    Selenium is an essential trace element because it is present in proteins in the form of selenocysteine residue. Functionally characterized selenoproteins are oxidoreductases. Selenoprotein methionine-R-sulfoxide reductase B1 (MsrB1) is a repair enzyme that reduces ROS-oxidized methionine residues in proteins. Here, we explored a possibility that reversible methionine oxidation is also a mechanism that regulates protein function. We found that MsrB1, together with Mical proteins, regulated mammalian actin assembly via stereospecific methionine oxidation and reduction in a reversible, site-specific manner. Two methionine residues in actin were specifically converted to methionine-R-sulfoxide by Mical1 and Mical2 and reduced back to methionine by MsrB1, supporting actin disassembly and assembly, respectively. Macrophages utilized this redox control during cellular activation by stimulating MsrB1 expression and activity. Thus, we identified the regulatory role of MsrB1 as a Mical antagonist in orchestrating actin dynamics and macrophage function. More generally, our study showed that proteins can be regulated by reversible site-specific methionine-R-sulfoxidation and that selenium is involved in this regulation by being a catalytic component of MsrB1. PMID:26461418

  4. Bimolecular photoreduction of aromatic sulfoxides.

    PubMed

    Cubbage, J W; Tetzlaff, T A; Groundwater, H; McCulla, R D; Nag, M; Jenks, W S

    2001-12-14

    Photolysis of aromatic sulfoxides in the presence of alkoxides in alcoholic solvents provides a photochemical route to the corresponding sulfides. Other electron donors also give sulfide with various degrees of success. The reaction could also be carried out using carbazoles as sensitizers, and quantitative yields could be obtained using N-methylcarbazole in methanol. Evidence points toward a hydroxysulfuranyl radical as the key intermediate, and solvent effects point to heterolysis, rather than homolysis, as the step that breaks the S-O bond. PMID:11735547

  5. 21 CFR 524.660a - Dimethyl sulfoxide solution.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Dimethyl sulfoxide solution. 524.660a Section 524... Dimethyl sulfoxide solution. (a) Specifications. Dimethyl sulfoxide contains 90 percent of dimethyl sulfoxide and 10 percent of water. (b) Sponsor. See No. 000856 in § 510.600(c) of this chapter....

  6. 21 CFR 524.660a - Dimethyl sulfoxide solution.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Dimethyl sulfoxide solution. 524.660a Section 524... Dimethyl sulfoxide solution. (a) Specifications. Dimethyl sulfoxide contains 90 percent of dimethyl sulfoxide and 10 percent of water. (b) Sponsor. See No. 000856 in § 510.600(c) of this chapter....

  7. 21 CFR 524.660a - Dimethyl sulfoxide solution.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Dimethyl sulfoxide solution. 524.660a Section 524... Dimethyl sulfoxide solution. (a) Specifications. Dimethyl sulfoxide contains 90 percent of dimethyl sulfoxide and 10 percent of water. (b) Sponsor. See No. 000856 in § 510.600(c) of this chapter....

  8. 21 CFR 524.660a - Dimethyl sulfoxide solution.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Dimethyl sulfoxide solution. 524.660a Section 524... Dimethyl sulfoxide solution. (a) Specifications. Dimethyl sulfoxide contains 90 percent of dimethyl sulfoxide and 10 percent of water. (b) Sponsor. See No. 000856 in § 510.600(c) of this chapter....

  9. 21 CFR 524.660b - Dimethyl sulfoxide gel.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Dimethyl sulfoxide gel. 524.660b Section 524.660b... Dimethyl sulfoxide gel. (a) Specifications. Dimethyl sulfoxide gel, veterinary contains 90 percent dimethyl sulfoxide in an aqueous gel. (b) Sponsor. See No. 000856 in § 510.600(c) of this chapter. (c) Conditions...

  10. Wanted and Wanting: Antibody Against Methionine Sulfoxide

    PubMed Central

    Wehr, Nancy B.; Levine, Rodney L.

    2012-01-01

    Methionine residues in protein can be oxidized by reactive oxygen or nitrogen species to generate methionine sulfoxide. This covalent modification has been implicated in processes ranging from normal cell signaling to neurodegenerative diseases. A general method for detecting methionine sulfoxide in proteins would be of great value in studying these processes, but development of a chemical or immunochemical technique has been elusive. Recently, an antiserum raised against an oxidized corn protein, DZS18, was reported to be specific for methionine sulfoxide in proteins (Arch. Biochem. Biophys. 485:35–40 2009.) However, data included in that report indicate that the antiserum is not specific. Utilizing well-characterized native and methionine-oxidized glutamine synthetase and aprotinin, we confirm that the antiserum does not possess specificity for methionine sulfoxide. PMID:22771451

  11. Dimethyl sulfoxide (DMSO): a review.

    PubMed

    Brayton, C F

    1986-01-01

    Dimethyl sulfoxide (DMSO) is a very simple compound that has stimulated much controversy in the scientific and popular literature. Fig. 1 It is an aprotic solvent. Therapeutic and toxic agents that are not soluble in water are often soluble in DMSO. DMSO has a very strong affinity for water; on exposure to air, pure DMSO is rapidly diluted. DMSO's physiologic and pharmacologic properties and effects are incompletely understood. Properties that are considered to be particularly important to its therapeutic and toxic effects include: its own rapid penetration and enhanced penetration of other substances across biologic membranes; free radical scavenging; effects on coagulation; anticholinesterase activity; and DMSO-induced histamine release by mast cells. DMSO's systemic toxicity is considered to be low. Combinations of DMSO with other toxic agents probably constitute its greatest toxic potential. The scientific literature is reviewed with particular attention to mechanisms underlying DMSO's reported therapeutic and toxic effects. Currently approved, veterinary applications of DMSO are limited. DMSO's potential value in specific, approved and unapproved veterinary applications is discussed. PMID:3510103

  12. Liquid structure of dibutyl sulfoxide.

    PubMed

    Lo Celso, Fabrizio; Aoun, Bachir; Triolo, Alessandro; Russina, Olga

    2016-06-21

    We present experimental (X-ray diffraction) data on the structure of liquid dibutyl sulfoxide at 320 K and rationalise the data by means of molecular dynamics simulations. Not unexpectedly, DBSO bearing a strong dipolar moiety and two medium length, apolar butyl chains, this compound was characterised by a distinct degree of polar vs. apolar structural differentiation at the nm spatial scale, which was fingerprinted by a low Q peak in its X-ray diffraction pattern. Similar to, but to a larger extent than its shorter chain family members (such as DMSO), DBSO was also characterised by an enhanced dipole-dipole correlation, which was responsible for a moderate Kirkwood correlation factor as well as for the self-association detected in this compound. We show, however, that the supposedly relevant hydrogen bonding correlations between oxygen and the butyl chain hydrogens are of a limited extent only, and only in the case of α-hydrogens is an appreciable indication of the existence of such an interaction found, albeit this turned out to be a mere consequence of the strong dipole-dipole correlation. PMID:27241730

  13. Enzymatic reduction of protein-bound methionine sulfoxide.

    PubMed Central

    Brot, N; Weissbach, L; Werth, J; Weissbach, H

    1981-01-01

    An enzyme that catalyzes the reduction of methionine sulfoxide residues in ribosomal protein L12 has been partially purified from Escherichia coli extracts. Methionine sulfoxide present in oxidize [Met]enkephalin is also reduced by the purified enzyme. The enzyme is different from a previously reported E. coli enzyme that catalyzes the reduction of methionine sulfoxide to methionine [Ejiri, S. I., Weissbach, H. & Brot, N. (1980) Anal. Biochem. 102, 393--398]. Extracts of rat tissues, Euglena gracilis, Tetrahymena pyriformis, HeLa cells, and spinach also can catalyze the reduction of methionine sulfoxide residues in protein. PMID:7017726

  14. Two new bicyclic sulfoxides from Welsh onion.

    PubMed

    Nohara, Toshihiro; Fujiwara, Yukio; Ikeda, Tsuyoshi; Murakami, Kotaro; Ono, Masateru; El-Aasr, Mona; Nakano, Daisuke; Kinjo, Junei

    2016-04-01

    Newly identified bicyclic sulfoxides, welsonins A1 (1) and A2 (2), were isolated from acetone extracts of the bulbs of the Welsh onion (Allium fistulosum). In this study, the structures of 1 and 2, which are tetrahydrothiophene-S-oxide derivatives, were characterized by spectroscopic analysis. These compounds appeared to be derived from the coupling of 1-propenyl sulfenic acid and uronic acid. Welsonin A1 (1) showed the potential to suppress tumor-cell proliferation by inhibiting the polarization of alternatively activated M2 macrophages. PMID:26676612

  15. Lithiated sulfoxides: α-sulfinyl functionalized carbanions.

    PubMed

    Ludwig, Gerd; Rüffer, Tobias; Hoppe, André; Walther, Till; Lang, Heinrich; Ebbinghaus, Stefan G; Steinborn, Dirk

    2015-03-28

    Reactions of alkyl aryl sulfoxides H-CRR'S(O)Ar with n-BuLi-TMEDA (TMEDA = N,N,N',N'-tetramethylethylenediamine) afforded α-sulfinyl functionalized alkyl aryl lithium compounds of the type [Li2{CRR'S(O)Ar}2(TMEDA)2] (1, R/R' = H/H, Ar = Ph; 2, R/R' = H/H, Ar = p-Tol; 3, R/R' = Me/Me, Ar = Ph; 4, R/R' = H/Ph, Ar = Ph; 5, R/R' = Me/Ph, Ar = Ph). The compounds were characterized by (1)H, (13)C and (7)Li NMR spectroscopy and, except for 5, by single-crystal X-ray diffraction analyses. In crystals of 1, 2, 3 and 4 ·Et2O dinuclear molecules with four-membered Li2O2 rings were found. There are no LiCα contacts, thus, "free" carbanions are the main structural feature. Reactions of 1-6 (6, R/R' = H/Me, Ar = Ph) with benzaldehyde and benzophenone afforded the corresponding sulfoxides of the type ArS(O)CRR'CHPhOH (1a-6a) and ArS(O)CRR'CPh2OH (1b-6b), respectively. The reactions yielding / and / proceeded with high diastereoselectivities. By X-ray diffractometry it has been shown that in the case of and the diastereomers consisting of the two enantiomers SSRC and RSSC were formed. PMID:25300739

  16. Identification of Methionine Sulfoxide Diastereomers in Immunoglobulin Gamma Antibodies Using Methionine Sulfoxide Reductase enzymes

    SciTech Connect

    Khor, Hui K.; Jacoby, Michael E.; Squier, Thomas C.; Chu, Grace C.; Chelius, Dirk

    2010-06-01

    During prolonged periods of storage methionines in antibodies and other proteins are known to become oxidized to form methionine sulfoxides and sulfones. While these post-translational modifications are commonly identified by peptide mapping, it is currently problematic to identify the relative abundances of the S- and R-diastereomers of methionine sulfoxide (Met(O)) due to their identical polarities and masses. Accordingly, we have developed a separation methodology for the rapid and quantitative determination of the relative abundances of Met(O) diastereomers. Identification of these diastereomers takes advantage of the complementary stereospecificities of methionine sulfoxide reductase (Msr) enzymes MsrA and MsrB, which respectively promote the selective reduction of S- and R-diastereomers of Met(O). In addition, an MsrBA fusion protein that contained both Msr enzyme activities permitted the quantitative reduction of all Met(O). Using these Msr enzymes in combination with peptide mapping we are able to detect and differentiate Met-diastereomers in a monoclonal IgG2 and IgG1 antibody. We also monitored the formation of sulfones and studied the rate of oxidation in the different Met residues in our IgG2 antibody. The reported ability to separate and identify diastereomers of Met(O) permits a more complete characterization of Met oxidation products. All the affected Met residues (M251, M427, M396) in this study are conserved in human IgG sequences and therefore offer predictive potential in characterizing oxidative modification.

  17. Albendazole sulfoxide enantiomers: preparative chiral separation and absolute stereochemistry.

    PubMed

    Lourenço, Tiago C; Batista, João M; Furlan, Maysa; He, Yanan; Nafie, Laurence A; Santana, Cesar C; Cass, Quezia B

    2012-03-23

    The enantiomeric separation of albendazole sulfoxide was carried out by simulated moving bed chromatography with variable zones (VARICOL). An overall recovery of 97% was achieved and enantiomeric ratios of 99.5% for raffinate and 99.0% for extract were attained. A total of 880 mg of (+)-albendazol sulfoxide and 930 mg of its antipode were collected after 55 cycles or 11 h of process, resulting in a mass rate of 2 g/day. Furthermore the absolute configuration of the enantiopure compounds was determined for the first time by vibrational circular dichroism (VCD) with the aid of theoretical calculations as (-)-(S) and (+)-(R)-albendazole sulfoxide. PMID:22341660

  18. Reduction of methionine sulfoxide to methionine by Escherichia coli.

    PubMed Central

    Ejiri, S I; Weissbach, H; Brot, N

    1979-01-01

    L-Methionine-dl-sulfoxide can support the growth of an Escherichia coli methionine auxotroph, suggesting the presence of an enzyme(s) capable of reducing the sulfoxide to methionine. This was verified by showing that a cell-free extract of E. coli catalyzes the conversion of methionine sulfoxide to methionine. This reaction required reduced nicotinamide adenine dinucleotide phosphate and a generating system for this compound. The specific activity of the enzyme increased during logarithmic growth and was maximal when the culture attained a density of about 10(9) cells per ml. PMID:37234

  19. Development of chiral sulfoxide ligands for asymmetric catalysis.

    PubMed

    Trost, Barry M; Rao, Meera

    2015-04-20

    Nitrogen-, phosphorus-, and oxygen-based ligands with chiral backbones have been the historic workhorses of asymmetric transition-metal-catalyzed reactions. On the contrary, sulfoxides containing chirality at the sulfur atom have mainly been used as chiral auxiliaries for diastereoselective reactions. Despite several distinct advantages over traditional ligand scaffolds, such as the proximity of the chiral information to the metal center and the ability to switch between S and O coordination, these compounds have only recently emerged as a versatile class of chiral ligands. In this Review, we detail the history of the development of chiral sulfoxide ligands for asymmetric catalysis. We also provide brief descriptions of metal-sulfoxide bonding and strategies for the synthesis of enantiopure sulfoxides. Finally, insights into the future development of this underutilized ligand class are discussed. PMID:25801825

  20. Facile Diastereoseparation of Glycosyl Sulfoxides by Chiral Stationary Phase.

    PubMed

    Taniguchi, Tohru; Asahata, Mai; Nasu, Akihito; Shichibu, Yukatsu; Konishi, Katsuaki; Monde, Kenji

    2016-07-01

    Separation of the diastereomers of glycosyl sulfoxides differing in the sulfur chirality has been difficult. This article presents a fast and scalable method for their diastereoseparation using a chiral stationary phase. The usefulness of this method was demonstrated in a 500-mg scale separation within 20 min, and in the separation of trisaccharyl sulfoxide diastereomers. Chirality 28:534-539, 2016. © 2016 Wiley Periodicals, Inc. PMID:27296702

  1. Chiral cyclopentadienylruthenium sulfoxide catalysts for asymmetric redox bicycloisomerization

    PubMed Central

    Ryan, Michael C; Rao, Meera

    2016-01-01

    Summary A full account of our efforts toward an asymmetric redox bicycloisomerization reaction is presented in this article. Cyclopentadienylruthenium (CpRu) complexes containing tethered chiral sulfoxides were synthesized via an oxidative [3 + 2] cycloaddition reaction between an alkyne and an allylruthenium complex. Sulfoxide complex 1 containing a p-anisole moiety on its sulfoxide proved to be the most efficient and selective catalyst for the asymmetric redox bicycloisomerization of 1,6- and 1,7-enynes. This complex was used to synthesize a broad array of [3.1.0] and [4.1.0] bicycles. Sulfonamide- and phosphoramidate-containing products could be deprotected under reducing conditions. Catalysis performed with enantiomerically enriched propargyl alcohols revealed a matched/mismatched effect that was strongly dependent on the nature of the solvent. PMID:27559366

  2. Mechanistic Investigations into the Application of Sulfoxides in Carbohydrate Synthesis

    PubMed Central

    Brabham, Robin

    2016-01-01

    Abstract The utility of sulfoxides in a diverse range of transformations in the field of carbohydrate chemistry has seen rapid growth since the first introduction of a sulfoxide as a glycosyl donor in 1989. Sulfoxides have since developed into more than just anomeric leaving groups, and today have multiple roles in glycosylation reactions. These include as activators for thioglycosides, hemiacetals, and glycals, and as precursors to glycosyl triflates, which are essential for stereoselective β‐mannoside synthesis, and bicyclic sulfonium ions that facilitate the stereoselective synthesis of α‐glycosides. In this review we highlight the mechanistic investigations undertaken in this area, often outlining strategies employed to differentiate between multiple proposed reaction pathways, and how the conclusions of these investigations have and continue to inform upon the development of more efficient transformations in sulfoxide‐based carbohydrate synthesis. PMID:26744250

  3. Chiral cyclopentadienylruthenium sulfoxide catalysts for asymmetric redox bicycloisomerization.

    PubMed

    Trost, Barry M; Ryan, Michael C; Rao, Meera

    2016-01-01

    A full account of our efforts toward an asymmetric redox bicycloisomerization reaction is presented in this article. Cyclopentadienylruthenium (CpRu) complexes containing tethered chiral sulfoxides were synthesized via an oxidative [3 + 2] cycloaddition reaction between an alkyne and an allylruthenium complex. Sulfoxide complex 1 containing a p-anisole moiety on its sulfoxide proved to be the most efficient and selective catalyst for the asymmetric redox bicycloisomerization of 1,6- and 1,7-enynes. This complex was used to synthesize a broad array of [3.1.0] and [4.1.0] bicycles. Sulfonamide- and phosphoramidate-containing products could be deprotected under reducing conditions. Catalysis performed with enantiomerically enriched propargyl alcohols revealed a matched/mismatched effect that was strongly dependent on the nature of the solvent. PMID:27559366

  4. Force field development and simulations of senior dialkyl sulfoxides.

    PubMed

    Chaban, Vitaly V

    2016-04-21

    Thermodynamics, structure, and dynamics of diethyl sulfoxide (DESO) and ethyl methyl sulfoxide (EMSO) were investigated using ab initio calculations and non-polarizable potential based molecular dynamics (MD) simulations. The additive pairwise force field (FF) for EMSO and DESO was proposed for the first time, preserving explicit compatibility with their most known homologue, DMSO. The simulations reveal similar structures and thermodynamic properties of DMSO, DESO and EMSO. However, the transport properties are significantly different: DESO and DMSO are less mobile and an order of magnitude more viscous. Furthermore, dipole reorientation in DESO and EMSO occurs ca. 2-4 times slower than in DMSO at room temperature. This observation favors applications of higher sulfoxides as cryoprotectants and provides a microscopic interpretation of the earlier experimental data. PMID:27031577

  5. Molybdenum cofactor requirement for biotin sulfoxide reduction in Escherichia coli.

    PubMed Central

    del Campillo-Campbell, A; Campbell, A

    1982-01-01

    The bisC gene of Escherichia coli is tentatively identified as the structural gene for biotin sulfoxide reductase by the isolation of bisC(Ts) mutants that make thermolabile enzyme. The products of four other E. coli genes (chlA, chlB, chlE and chlG) are also needed for enzymatic activity. Mutations previously assigned to the bisA, bisB, and bisD genes belong to genes chlA, chlE, and chlG, respectively. The biotin sulfoxide reductase deficiency of a chlG, mutant is partially reversed by the addition of 10 mM molybdate to the growth medium. Mutational inactivation of the chlD gene reduces the specific activity of biotin sulfoxide reductase about twofold. This effect is reversed by the addition of 1 mM molybdate to the growth medium. The specific activity of biotin sulfoxide reductase is decreased about 30-fold by the presence of tungstate in the growth medium, an effect that has been observed previously with nitrate reductase and other molybdoenzymes. The specific activity of biotin sulfoxide reductase is not elevated in a lysate prepared by derepressing a lambda cI857 chlG prophage. Whereas biotin sulfoxide reductase prepared by sonic extraction of growing cells is almost completely dependent on the presence of a small heat-stable protein resembling thioredoxin, much of the enzyme obtained from lysates of thermoinduced lambda cI857 lysogens does not require this factor. PMID:6460021

  6. Excited state dynamics and isomerization in ruthenium sulfoxide complexes.

    PubMed

    King, Albert W; Wang, Lei; Rack, Jeffrey J

    2015-04-21

    Molecular photochromic compounds are those that interconvert between two isomeric forms with light. The two isomeric forms display distinct electronic and molecular structures and must not be in equilibrium with one another. These light-activated molecular switch compounds have found wide application in areas of study ranging from chemical biology to materials science, where conversion from one isomeric form to another by light prompts a response in the environment (e.g., protein or polymeric material). Certain ruthenium and osmium polypyridine sulfoxide complexes are photochromic. The mode of action is a phototriggered isomerization of the sulfoxide from S- to O-bonded. The change in ligation drastically alters both the spectroscopic and electrochemical properties of the metal complex. Our laboratory has pioneered the preparation and study of these complexes. In particular, we have applied femtosecond pump-probe spectroscopy to reveal excited state details of the isomerization mechanism. The data from numerous complexes allowed us to predict that the isomerization was nonadiabatic in nature, defined as occurring from a S-bonded triplet excited state (primarily metal-to-ligand charge transfer in character) to an O-bonded singlet ground state potential energy surface. This prediction was corroborated by high-level density functional theory calculations. An intriguing aspect of this reactivity is the coupling of nuclear motion to the electronic wave function and how this coupling affects motions productive for isomerization. In an effort to learn more about this coupling, we designed a project to examine phototriggered isomerization in bis-sulfoxide complexes. The goal of these studies was to determine whether certain complexes could be designed in which a single photon excitation event would prompt two sulfoxide isomerizations. We employed chelating sulfoxides in this study and found that both the nature of the chelate ring and the R group on the sulfoxide affect

  7. 21 CFR 524.981e - Fluocinolone and dimethyl sulfoxide otic solution.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Fluocinolone and dimethyl sulfoxide otic solution... ANIMAL DRUGS § 524.981e Fluocinolone and dimethyl sulfoxide otic solution. (a) Specifications. Each milliliter of solution contains 0.01 percent fluocinolone acetonide and 60 percent dimethyl sulfoxide....

  8. Monitoring methionine sulfoxide with stereospecific mechanism-based fluorescent sensors

    PubMed Central

    Tarrago, Lionel; Péterfi, Zalán; Lee, Byung Cheon; Michel, Thomas; Gladyshev, Vadim N.

    2015-01-01

    Methionine can be reversibly oxidized to methionine sulfoxide (MetO) under physiological and pathophysiological conditions, but its use as a redox marker suffers from the lack of tools to detect and quantify MetO within cells. In this work, we created a pair of complementary stereospecific genetically-encoded mechanism-based ratiometric fluorescent sensors of MetO by inserting a circularly yellow fluorescent protein between yeast methionine sulfoxide reductases and thioredoxins. The two sensors, named MetSOx and MetROx for their ability to detect S and R-forms of MetO, respectively, were utilized for targeted analysis of protein oxidation, regulation and repair, as well as for monitoring MetO in bacterial and mammalian cells, analyzing compartment-specific changes in MetO, and examining responses to physiological stimuli. PMID:25799144

  9. Light-Mediated Sulfenic Acid Generation from Photocaged Cysteine Sulfoxide.

    PubMed

    Pan, Jia; Carroll, Kate S

    2015-12-18

    S-Sulfenylation is a post-translational modification with a crucial role in regulating protein function. However, its analysis has remained challenging due to the lack of facile sulfenic acid models. We report the first photocaged cysteine sulfenic acid with efficient photodeprotection and demonstrate its utility by generating sulfenic acid in a thiol peroxidase after illumination in vitro. These caged sulfoxides should be promising for site-specific incorporation of Cys sulfenic acid in living cells via genetic code expansion. PMID:26641493

  10. Aryne 1,2,3-Trifunctionalization with Aryl Allyl Sulfoxides.

    PubMed

    Li, Yuanyuan; Qiu, Dachuan; Gu, Rongrong; Wang, Junli; Shi, Jiarong; Li, Yang

    2016-08-31

    An aryne 1,2,3-trisubstitution with aryl allyl sulfoxides is accomplished, featuring an incorporation of C-S, C-O, and C-C bonds on the consecutive positions of a benzene ring. The reaction condition is mild with broad substrate scope. Preliminary mechanistic study suggests a cascade formal [2 + 2] reaction of aryne with S═O bond, an allyl S → O migration, and a Claisen rearrangement. PMID:27527334

  11. Aryl sulfoxide radical cations. Generation, spectral properties, and theoretical calculations.

    PubMed

    Baciocchi, Enrico; Del Giacco, Tiziana; Gerini, Maria Francesca; Lanzalunga, Osvaldo

    2006-08-17

    Aromatic sulfoxide radical cations have been generated by pulse radiolysis and laser flash photolysis techniques. In water (pulse radiolysis) the radical cations showed an intense absorption band in the UV region (ca. 300 nm) and a broad less intense band in the visible region (from 500 to 1000 nm) whose position depends on the nature of the ring substituent. At very low pulse energy, the radical cations decayed by first-order kinetics, the decay rate increasing as the pH increases. It is suggested that the decay involves a nucleophilic attack of H(2)O or OH(-) (in basic solutions) to the positively charged sulfur atom to give the radical ArSO(OH)CH(3)(*). By sensitized [N-methylquinolinium tetrafluoborate (NMQ(+))] laser flash photolysis (LFP) the aromatic sulfoxide radical cations were generated in acetonitrile. In these experiments, however, only the band of the radical cation in the visible region could be observed, the UV band being covered by the UV absorption of NMQ(+). The lambda(max) values of the bands in the visible region resulted almost identical to those observed in water for the same radical cations. In the LFP experiments the sulfoxide radical cations decayed by second-order kinetics at a diffusion-controlled rate, and the decay is attributed to the back electron transfer between the radical cation and NMQ(*). DFT calculations were also carried out for a number of 4-X ring substituted (X = H, Me, Br, OMe, CN) aromatic sulfoxide radical cations (and their neutral parents). In all radical cations, the conformation with the S-O bond almost coplanar with the aromatic ring is the only one corresponding to the energy minimum. The maximum of energy corresponds to the conformation where the S-O bond is perpendicular to the aromatic ring. The rotational energy barriers are not very high, ranging from 3.9 to 6.9 kcal/mol. In all radical cations, the major fraction of charge and spin density is localized on the SOMe group. However, a substantial delocalization

  12. C-H Coupling Reactions Directed by Sulfoxides: Teaching an Old Functional Group New Tricks.

    PubMed

    Pulis, Alexander P; Procter, David J

    2016-08-16

    Sulfoxides are classical functional groups for directing the stoichiometric metalation and functionalization of C-H bonds. In recent times, sulfoxides have been given a new lease on life owing to the development of modern synthetic methods that have arisen because of their unique reactivity. They have recently been used in catalytic C-H activation proceeding via coordination of an internal sulfoxide to a metal or through the action of an external sulfoxide ligand. Furthermore, sulfoxides are able to capture nucleophiles and electrophiles to give sulfonium salts, which subsequently enable the formation of C-C bonds at the expense of C-H bonds. This Review summarizes a renaissance period in the application of sulfoxides arising from their versatility in directing C-H functionalization. PMID:27409984

  13. Ineffectiveness of topical idoxuridine in dimethyl sulfoxide for therapy for genital herpes.

    PubMed

    Silvestri, D L; Corey, L; Holmes, K K

    1982-08-27

    The efficacy and toxicity of topical applications of 30% idoxuridine in dimethyl sulfoxide, dimethyl sulfoxide alone, or saline in 96 recurrent and 39 first episodes of genital herpes simplex virus (HSV) infection were compared. Drug was applied to lesions four times daily for seven days. In recurrent episodes, the duration of viral shedding after beginning idoxuridine in dimethyl sulfoxide use was significantly shorter (0.6 days) than with dimethyl sulfoxide (1.4 days) or saline (2.0 days) (P less than .05). In primary episodes, viral shedding lasted 2.6 days with idoxuridine in dimethyl sulfoxide and 8.4 days with dimethyl sulfoxide or saline. Idoxuridine in dimethyl sulfoxide had no effect in recurrent or primary HSV on duration of symptoms, new lesion formation, healing time, or risk of subsequent recurrence. Complications in patients given idoxuridine in dimethyl sulfoxide included local burning, generalized contact dermatitis, and vulvar carcinoma in situ. Thirty percent idoxuridine in dimethyl sulfoxide has no effect on clinical manifestations of genital HSV infection and may be hazardous. PMID:7047788

  14. Tandem rhodium catalysis:Exploiting sulfoxides for asymmetric transition-metal catalysis

    PubMed Central

    Kou, K. G. M.

    2015-01-01

    Sulfoxides are uncommon substrates for transition-metal catalysis due to their propensity to inhibit catalyst turnover. In a collaborative effort with Ken Houk, we developed the first dynamic kinetic resolution (DKR) of allylic sulfoxides using asymmetric rhodium-catalyzed hydrogenation. Detailed mechanistic analysis of this transformation using both experimental and theoretical methods revealed rhodium to be a tandem catalyst that promoted both hydrogenation of the alkene and racemization of the allylic sulfoxide. Using a combination of deuterium labelling and DFT studies, a novel mode of allylic sulfoxide racemization via a Rh(III)-π-allyl intermediate was identified. PMID:25940066

  15. Acidity of Strong Acids in Water and Dimethyl Sulfoxide.

    PubMed

    Trummal, Aleksander; Lipping, Lauri; Kaljurand, Ivari; Koppel, Ilmar A; Leito, Ivo

    2016-05-26

    Careful analysis and comparison of the available acidity data of HCl, HBr, HI, HClO4, and CF3SO3H in water, dimethyl sulfoxide (DMSO), and gas-phase has been carried out. The data include experimental and computational pKa and gas-phase acidity data from the literature, as well as high-level computations using different approaches (including the W1 theory) carried out in this work. As a result of the analysis, for every acid in every medium, a recommended acidity value is presented. In some cases, the currently accepted pKa values were revised by more than 10 orders of magnitude. PMID:27115918

  16. SWELLING OF PEATS IN LIQUID METHYL, TETRAMETHYLENE AND PROPYL SULFOXIDES AND IN LIQUID PROPYL SULFONE

    EPA Science Inventory

    The interactions of methyl, tetramethylene, and propyl sulfoxides and propyl sulfone during sorption onto four de-waxed, acid-form peats have been studied by means of swelling measurements. The results for sulfoxides are displayed as het-eromolecular sorption isotherms, which plo...

  17. 21 CFR 524.660 - Dimethyl sulfoxide ophthalmic and topical dosage forms.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Dimethyl sulfoxide ophthalmic and topical dosage... HUMAN SERVICES (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS OPHTHALMIC AND TOPICAL DOSAGE FORM NEW ANIMAL DRUGS § 524.660 Dimethyl sulfoxide ophthalmic and topical dosage forms....

  18. Determination of the specific activities of methionine sulfoxide reductase A and B by capillary electrophoresis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A capillary electrophoresis (CE) method for the determination of methionine sulfoxide reductase A and methionine sulfoxide reductase B activities in mouse liver is described. The method is based on detection of the 4-(dimethylamino)azobenzene-4’-sulfonyl derivative of L-methionine (dabsyl Met), the ...

  19. FT-IR SOLUTION SPECTRA OF PROPYL SULFIDE, PROPYL SULFOXIDE, AND PROPYL SULFONE

    EPA Science Inventory

    FT-IR spectra were obtained of 0.5% volumetric solutions of propyl sulfide, propyl sulfoxide, and propyl sulfone in hexane, CCl4, CS2, and CHCl3 to assist in the assignment of FT-IR-PAS spectra of propyl sulfoxide sorbed within the structure of several peats and onto cellulose. T...

  20. FTIR SOLUTION SPECTRA OF PROPYL SULFIDE, PROPYL SULFOXIDE, AND PROPYL SULFONE

    EPA Science Inventory

    FTIR spectra were obtained of 0.5% volumetric solutions of propyl sulfide, propyl sulfoxide and propyl sulfone in hexane, CC14, CS2, and CHCl3 to assist in the assignment of FTIR-PAS spectra of propyl sulfoxide sorbed within the structure of several peats and onto cellulose. he C...

  1. Lithium solvation in dimethyl sulfoxide-acetonitrile mixtures.

    PubMed

    Semino, Rocío; Zaldívar, Gervasio; Calvo, Ernesto J; Laria, Daniel

    2014-12-01

    We present molecular dynamics simulation results pertaining to the solvation of Li(+) in dimethyl sulfoxide-acetonitrile binary mixtures. The results are potentially relevant in the design of Li-air batteries that rely on aprotic mixtures as solvent media. To analyze effects derived from differences in ionic size and charge sign, the solvation of Li(+) is compared to the ones observed for infinitely diluted K(+) and Cl(-) species, in similar solutions. At all compositions, the cations are preferentially solvated by dimethyl sulfoxide. Contrasting, the first solvation shell of Cl(-) shows a gradual modification in its composition, which varies linearly with the global concentrations of the two solvents in the mixtures. Moreover, the energetics of the solvation, described in terms of the corresponding solute-solvent coupling, presents a clear non-ideal concentration dependence. Similar nonlinear trends were found for the stabilization of different ionic species in solution, compared to the ones exhibited by their electrically neutral counterparts. These tendencies account for the characteristics of the free energy associated to the stabilization of Li(+)Cl(-), contact-ion-pairs in these solutions. Ionic transport is also analyzed. Dynamical results show concentration trends similar to those recently obtained from direct experimental measurements. PMID:25481154

  2. Lithium solvation in dimethyl sulfoxide-acetonitrile mixtures

    SciTech Connect

    Semino, Rocío; Zaldívar, Gervasio; Calvo, Ernesto J.; Laria, Daniel

    2014-12-07

    We present molecular dynamics simulation results pertaining to the solvation of Li{sup +} in dimethyl sulfoxide-acetonitrile binary mixtures. The results are potentially relevant in the design of Li-air batteries that rely on aprotic mixtures as solvent media. To analyze effects derived from differences in ionic size and charge sign, the solvation of Li{sup +} is compared to the ones observed for infinitely diluted K{sup +} and Cl{sup −} species, in similar solutions. At all compositions, the cations are preferentially solvated by dimethyl sulfoxide. Contrasting, the first solvation shell of Cl{sup −} shows a gradual modification in its composition, which varies linearly with the global concentrations of the two solvents in the mixtures. Moreover, the energetics of the solvation, described in terms of the corresponding solute-solvent coupling, presents a clear non-ideal concentration dependence. Similar nonlinear trends were found for the stabilization of different ionic species in solution, compared to the ones exhibited by their electrically neutral counterparts. These tendencies account for the characteristics of the free energy associated to the stabilization of Li{sup +}Cl{sup −}, contact-ion-pairs in these solutions. Ionic transport is also analyzed. Dynamical results show concentration trends similar to those recently obtained from direct experimental measurements.

  3. Lithium solvation in dimethyl sulfoxide-acetonitrile mixtures

    NASA Astrophysics Data System (ADS)

    Semino, Rocío; Zaldívar, Gervasio; Calvo, Ernesto J.; Laria, Daniel

    2014-12-01

    We present molecular dynamics simulation results pertaining to the solvation of Li+ in dimethyl sulfoxide-acetonitrile binary mixtures. The results are potentially relevant in the design of Li-air batteries that rely on aprotic mixtures as solvent media. To analyze effects derived from differences in ionic size and charge sign, the solvation of Li+ is compared to the ones observed for infinitely diluted K+ and Cl- species, in similar solutions. At all compositions, the cations are preferentially solvated by dimethyl sulfoxide. Contrasting, the first solvation shell of Cl- shows a gradual modification in its composition, which varies linearly with the global concentrations of the two solvents in the mixtures. Moreover, the energetics of the solvation, described in terms of the corresponding solute-solvent coupling, presents a clear non-ideal concentration dependence. Similar nonlinear trends were found for the stabilization of different ionic species in solution, compared to the ones exhibited by their electrically neutral counterparts. These tendencies account for the characteristics of the free energy associated to the stabilization of Li+Cl-, contact-ion-pairs in these solutions. Ionic transport is also analyzed. Dynamical results show concentration trends similar to those recently obtained from direct experimental measurements.

  4. Synthesis of enyne and aryl vinyl sulfoxides: functionalization via Pummerer rearrangement.

    PubMed

    Souza, Frederico B; Shamim, Anwar; Argomedo, Luiz M Z; Pimenta, Daniel C; Stefani, Hélio A

    2015-11-01

    An efficient methodology for the synthesis of aryl-substituted vinyl sulfoxides through direct substitution of aryl-substituted alkynyl grignard reagents on menthyl-p-toluenesulfinate followed by Suzuki-Miyaura cross-coupling reaction has been developed. It has also been described that the reaction of alkyl-substituted and cycloalkyl-substituted alkynyl grignard reagents with menthyl-p-toluenesulfinate led to two products, i.e., alkynyl sulfoxide derivatives, as a result of substitution, and enyne sulfoxide derivatives, which resulted from substitution followed by Michael type addition. It was possible to selectively synthesize the enyne sulfoxide derivatives by changing the concentration of the grignard reagent. These alkenyl sulfoxides were transformed into the corresponding [Formula: see text]-thio aldehydes in high yields via additive Pummerer rearrangement. PMID:26232026

  5. In vitro analysis of albendazole sulfoxide enantiomers shows that (+)-(R)-albendazole sulfoxide is the active enantiomer against Taenia solium.

    PubMed

    Paredes, Adriana; de Campos Lourenço, Tiago; Marzal, Miguel; Rivera, Andrea; Dorny, Pierre; Mahanty, Siddhartha; Guerra-Giraldez, Cristina; García, Hector H; Nash, Theodore E; Cass, Quezia B

    2013-02-01

    Albendazole is an anthelmintic drug widely used in the treatment of neurocysticercosis (NCC), an infection of the brain with Taenia solium cysts. However, drug levels of its active metabolite, albendazole sulfoxide (ABZSO), are erratic, likely resulting in decreased efficacy and suboptimal cure rates in NCC. Racemic albendazole sulfoxide is composed of ABZSO (+)-(R)- and (-)-(S) enantiomers that have been shown to differ in pharmacokinetics and activity against other helminths. The antiparasitic activities of racemic ABZSO and its (+)-(R)- and (-)-(S) enantiomers against T. solium cysts were evaluated in vitro. Parasites were collected from naturally infected pigs, cultured, and exposed to the racemic mixture or to each enantiomer (range, 10 to 500 ng/ml) or to praziquantel as a reference drug. The activity of each compound against cysts was assayed by measuring the ability to evaginate and inhibition of alkaline phosphatase (AP) and parasite antigen release. (+)-(R)-ABZSO was significantly more active than (-)-(S)-ABZSO in suppressing the release of AP and antigen into the supernatant in a dose- and time-dependent manner, indicating that most of the activity of ABZSO resides in the (+)-(R) enantiomer. Use of this enantiomer alone may lead to increased efficacy and/or less toxicity compared to albendazole. PMID:23229490

  6. In Vitro Analysis of Albendazole Sulfoxide Enantiomers Shows that (+)-(R)-Albendazole Sulfoxide Is the Active Enantiomer against Taenia solium

    PubMed Central

    Paredes, Adriana; de Campos Lourenço, Tiago; Marzal, Miguel; Rivera, Andrea; Dorny, Pierre; Mahanty, Siddhartha; Guerra-Giraldez, Cristina; García, Hector H.; Cass, Quezia B.

    2013-01-01

    Albendazole is an anthelmintic drug widely used in the treatment of neurocysticercosis (NCC), an infection of the brain with Taenia solium cysts. However, drug levels of its active metabolite, albendazole sulfoxide (ABZSO), are erratic, likely resulting in decreased efficacy and suboptimal cure rates in NCC. Racemic albendazole sulfoxide is composed of ABZSO (+)-(R)- and (−)-(S) enantiomers that have been shown to differ in pharmacokinetics and activity against other helminths. The antiparasitic activities of racemic ABZSO and its (+)-(R)- and (−)-(S) enantiomers against T. solium cysts were evaluated in vitro. Parasites were collected from naturally infected pigs, cultured, and exposed to the racemic mixture or to each enantiomer (range, 10 to 500 ng/ml) or to praziquantel as a reference drug. The activity of each compound against cysts was assayed by measuring the ability to evaginate and inhibition of alkaline phosphatase (AP) and parasite antigen release. (+)-(R)-ABZSO was significantly more active than (−)-(S)-ABZSO in suppressing the release of AP and antigen into the supernatant in a dose- and time-dependent manner, indicating that most of the activity of ABZSO resides in the (+)-(R) enantiomer. Use of this enantiomer alone may lead to increased efficacy and/or less toxicity compared to albendazole. PMID:23229490

  7. Bacterial dioxygenase- and monooxygenase-catalysed sulfoxidation of benzo[b]thiophenes.

    PubMed

    Boyd, Derek R; Sharma, Narain D; McMurray, Brian; Haughey, Simon A; Allen, Christopher C R; Hamilton, John T G; McRoberts, W Colin; O'Ferrall, Rory A More; Nikodinovic-Runic, Jasmina; Coulombel, Lydie A; O'Connor, Kevin E

    2012-01-28

    Asymmetric heteroatom oxidation of benzo[b]thiophenes to yield the corresponding sulfoxides was catalysed by toluene dioxygenase (TDO), naphthalene dioxygenase (NDO) and styrene monooxygenase (SMO) enzymes present in P. putida mutant and E. coli recombinant whole cells. TDO-catalysed oxidation yielded the relatively unstable benzo[b]thiophene sulfoxide; its dimerization, followed by dehydrogenation, resulted in the isolation of stable tetracyclic sulfoxides as minor products with cis-dihydrodiols being the dominant metabolites. SMO mainly catalysed the formation of enantioenriched benzo[b]thiophene sulfoxide and 2-methyl benzo[b]thiophene sulfoxides which racemized at ambient temperature. The barriers to pyramidal sulfur inversion of 2- and 3-methyl benzo[b]thiophene sulfoxide metabolites, obtained using TDO and NDO as biocatalysts, were found to be ca.: 25-27 kcal mol(-1). The absolute configurations of the benzo[b]thiophene sulfoxides were determined by ECD spectroscopy, X-ray crystallography and stereochemical correlation. A site-directed mutant E. coli strain containing an engineered form of NDO, was found to change the regioselectivity toward preferential oxidation of the thiophene ring rather than the benzene ring. PMID:22134441

  8. Subnanosecond isomerization in an osmium-dimethyl sulfoxide complex.

    PubMed

    Mockus, Nicholas V; Petersen, Jeffrey L; Rack, Jeffrey J

    2006-01-01

    We report the structure, spectroscopy, and electrochemistry of cis-[Os(bpy)(2)(DMSO)(2)](OTf)(2), where bpy is 2,2'-bipyridine, DMSO is dimethyl sulfoxide, and OTf is trifluoromethanesulfonate. Electrochemical measurements are consistent with S-to-O isomerization following the oxidation of Os(2+) (1.8 V vs Ag/AgCl). Visible irradiation of the metal-to-ligand charge-transfer transition (355 nm) of [Os(bpy)(2)(DMSO)(2)](2+) in the solid state and solution yields an emissive S-bonded excited state and S-to-O excited-state isomerization on a subnanosecond time scale. These results and a comparison to the nonphotoactive [Os(bpy)(2)Cl(DMSO)](+) are discussed. PMID:16390034

  9. Trimesic acid dimethyl sulfoxide solvate: space group revision

    PubMed Central

    Bernès, Sylvain; Hernández, Guadalupe; Portillo, Roberto; Gutiérrez, René

    2008-01-01

    The structure of the title solvate, C9H6O6·C2H6OS, was determined 30 years ago [Herbstein, Kapon & Wasserman (1978 ▶). Acta Cryst. B34, 1613–1617], with data collected at room temperature, and refined in the space group P21. The present redetermination, based on high-resolution diffraction data, shows that the actual space group is more likely to be P21/m. The crystal structure contains layers of trimesic acid molecules lying on mirror planes. A mirror plane also passes through the S and O atoms of the solvent molecule. The molecules in each layer are inter­connected through strong O—H⋯O hydrogen bonds, forming a two-dimensional supra­molecular network within each layer. The donor groups are the hydroxyls of the trimesic acid mol­ecules, while the acceptors are the carbonyl or the sulfoxide O atoms. PMID:21202984

  10. Transformation and adsorption of Fenamiphos, f. sulfoxide and f. sulfone in molokai soil and simulated movement with irrigation

    NASA Astrophysics Data System (ADS)

    Lee, Chee-Chow; Green, Richard E.; Apt, Walter J.

    1986-02-01

    The ban of commonly used soil fumigants, DBCP and EDB, for control of nematodes in pineapple fields has prompted investigations into a non-fumigant nematicide, fenamiphos (Nemacur ®). The transformation and adsorption in soil of fenamiphos and its transformation products, f. sulfoxide and f. sulfone were studied in the laboratory. Fenamiphos adsorption on soil exceeded that of f. sulfoxide and f. sulfone. F. sulfoxide, however, was the most persistent. A one-dimensional simulation model was used to assess the impact of transformation and adsorption on the mobility and distribution of fenamiphos and f. sulfoxide in soil. Simulated results showed that fenamiphos stayed in the topsoil and transformed rapidly to f. sulfoxide. Because of the persistence and mobility of f. sulfoxide, this metabolite leached rapidly and significant amounts remained in the soil. This suggests that for times exceeding three weeks, f. sulfoxide may be the dominant compound providing nematode control in drip-irrigated pineapple.

  11. Distribution of zirconium in petroleum sulfoxides during extraction and sorption from nitric and hydrochloric acid solutions

    SciTech Connect

    Turanov, A.N.

    1988-11-20

    Petroleum sulfoxides (PSO) are effective extractants for several metals. We discussed the distribution of petroleum sulfoxides and zirconium between aqueous solutions of hydrochloric and nitric acid and organic solvents, and also the macroporous sorbent impregnated with PSO. For the investigation we used a macroposous copolymer of styrene with divinylbenzene. Our investigation showed a noticeable decrease in the contamination of the raffinates by petroleum sulfoxides and their more complete utilization as extractant of metals from solutions of acids when PSO is deposited on a macroporous copolymer of styrene with divinylbenzene.

  12. Diversity of Plant Methionine Sulfoxide Reductases B and Evolution of a Form Specific for Free Methionine Sulfoxide

    PubMed Central

    Le, Dung Tien; Tarrago, Lionel; Watanabe, Yasuko; Kaya, Alaattin; Lee, Byung Cheon; Tran, Uyen; Nishiyama, Rie; Fomenko, Dmitri E.; Gladyshev, Vadim N.; Tran, Lam-Son Phan

    2013-01-01

    Methionine can be reversibly oxidized to methionine sulfoxide (MetO) under physiological conditions. Organisms evolved two distinct methionine sulfoxide reductase families (MSRA & MSRB) to repair oxidized methionine residues. We found that 5 MSRB genes exist in the soybean genome, including GmMSRB1 and two segmentally duplicated gene pairs (GmMSRB2 and GmMSRB5, GmMSRB3 and GmMSRB4). GmMSRB2 and GmMSRB4 proteins showed MSRB activity toward protein-based MetO with either DTT or thioredoxin (TRX) as reductants, whereas GmMSRB1 was active only with DTT. GmMSRB2 had a typical MSRB mechanism with Cys121 and Cys 68 as catalytic and resolving residues, respectively. Surprisingly, this enzyme also possessed the MSRB activity toward free Met-R-O with kinetic parameters similar to those reported for fRMSR from Escherichia coli, an enzyme specific for free Met-R-O. Overexpression of GmMSRB2 or GmMSRB4 in the yeast cytosol supported the growth of the triple MSRA/MSRB/fRMSR (Δ3MSRs) mutant on MetO and protected cells against H2O2-induced stress. Taken together, our data reveal an unexpected diversity of MSRBs in plants and indicate that, in contrast to mammals that cannot reduce free Met-R-O and microorganisms that use fRMSR for this purpose, plants evolved MSRBs for the reduction of both free and protein-based MetO. PMID:23776515

  13. cis-Bis(2,2'-bipyridine-κN,N')bis-(dimethyl sulfoxide-κO)zinc bis-(tetra-phenyl-borate) dimethyl sulfoxide monosolvate.

    PubMed

    Tomyn, Stefania; Gumienna-Kontecka, Elżbieta; Usenko, Natalia I; Iskenderov, Turganbay S; Prisyazhnaya, Elena V

    2011-12-01

    In the mononuclear title complex, [Zn(C(10)H(8)N(2))(2)(C(2)H(6)OS)(2)](C(24)H(20)B)(2)·C(2)H(6)OS, the Zn(II) ion is coordinated by four N atoms of two bidentate 2,2'-bipyridine mol-ecules and by the O atoms of two cis-disposed dimethyl sulfoxide mol-ecules in a distorted octa-hedral geometry. The S atom and the methyl groups of one of the coordinated dimethyl sulfoxide mol-ecules are disordered in a 0.509 (2):0.491 (2) ratio. The crystal packing is stabilized by C-H⋯O hydrogen bonds between the dimethyl sulfoxide solvent mol-ecules and tetra-phenyl-borate anions. PMID:22199567

  14. Does dimethyl sulfoxide increase protein immunomarking efficiency for dispersal and predation studies?

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Marking biological control agents facilitates studies of dispersal and predation. This study examines the effect of a biological solvent, dimethyl sulfoxide (DMSO), on retention of immunoglobulin G (IgG) protein solutions applied to Diorhabda carinulata (Desbrochers) (Coleoptera: Chrysomelidae) eit...

  15. 21 CFR 524.981e - Fluocinolone acetonide, dimethyl sulfoxide otic solution.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... sensitivity testing, and the use of the appropriate antimicrobial agent. As with any corticosteroid, animals... antimicrobial therapy. Preparations with dimethyl sulfoxide should not be used in pregnant animals. For use...

  16. 21 CFR 524.981e - Fluocinolone acetonide, dimethyl sulfoxide otic solution.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... sensitivity testing, and the use of the appropriate antimicrobial agent. As with any corticosteroid, animals... antimicrobial therapy. Preparations with dimethyl sulfoxide should not be used in pregnant animals. For use...

  17. 21 CFR 524.981e - Fluocinolone acetonide, dimethyl sulfoxide otic solution.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... sensitivity testing, and the use of the appropriate antimicrobial agent. As with any corticosteroid, animals... antimicrobial therapy. Preparations with dimethyl sulfoxide should not be used in pregnant animals. For use...

  18. 21 CFR 524.981e - Fluocinolone acetonide, dimethyl sulfoxide otic solution.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... sensitivity testing, and the use of the appropriate antimicrobial agent. As with any corticosteroid, animals... antimicrobial therapy. Preparations with dimethyl sulfoxide should not be used in pregnant animals. For use...

  19. Stereochemistry of 10-sulfoxidation catalyzed by a soluble delta9 desaturase

    SciTech Connect

    Tremblay, A.E.; Shanklin, J.; Tan, N.; Whittle, E.; Hodgson, D. J.; Dawson, B.; Buist, P. H.

    2010-03-21

    The stereochemistry of castor stearoyl-ACP 9 desaturase-mediated 10-sulfoxidation has been determined. This was accomplished by 19F NMR analysis of a fluorine-tagged product, 18-fluoro-10-thiastearoyl ACP S-oxide, in combination with a chiral solvating agent, (R)-AMA. Sulfoxidation proceeds with the same stereoselectivity as hydrogen removal from the parent stearoyl substrate. These data validate the use of thia probes to determine the stereochemistry and cryptoregiochemistry of desaturase-mediated oxidations.

  20. Chiral sulfoxides in the enantioselective allylation of aldehydes with allyltrichlorosilane: a kinetic study.

    PubMed

    Monaco, Guglielmo; Vignes, Chiara; De Piano, Francesco; Bosco, Assunta; Massa, Antonio

    2012-12-28

    The mechanism of the allylation of aldehydes in the presence of allyltrichlorosilane employing the commercially available (R)-methyl p-tolyl sulfoxide as a Lewis base has been investigated. The combination of kinetic measurements, conductivity analysis and quantum chemical calculations indicates that the reaction proceeds through a dissociative pathway in which an octahedral cationic complex with two sulfoxides is involved. The lack of turnover is ascribed to the formation of neutral sulfurane derivatives. PMID:23139050

  1. Enantiomerization of Allylic Trifluoromethyl Sulfoxides Studied by HPLC Analysis and DFT Calculations.

    PubMed

    Bailly, Laetitia; Petit, Emilie; Maeno, Mayaka; Shibata, Norio; Trapp, Oliver; Cardinael, Pascal; Chataigner, Isabelle; Cahard, Dominique

    2016-02-01

    Enantiomerization of allylic trifluoromethyl sulfoxides occurs spontaneously at room temperature through the corresponding allylic trifluoromethanesulfenates via a [2,3]-sigmatropic rearrangement. Dynamic enantioselective high-performance liquid chromatography (HPLC) analysis revealed the stereodynamics of these sulfoxides ranging from chromatographic resolution to peak coalescence at temperatures between 5 and 53 °C. The rate constant of enantiomerization and activation parameters were determined and compared with Density Functional Theory (DFT) calculations. PMID:26689286

  2. Effect of sulfoxides on the thermal denaturation of hen lysozyme: A calorimetric and Raman study

    NASA Astrophysics Data System (ADS)

    Torreggiani, A.; Di Foggia, M.; Manco, I.; De Maio, A.; Markarian, S. A.; Bonora, S.

    2008-11-01

    A multidisciplinary study of the thermal denaturation of lysozyme in the presence of three sulfoxides with different length in hydrocarbon chain (DMSO, DESO, and DPSO) was carried out by means of DSC, Raman spectroscopy, and SDS-PAGE techniques. In particular, the Td and Δ H values obtained from the calorimetric measurements showed that lysozyme is partially unfolded by sulfoxides but most of the conformation holds native state. The sulfoxide denaturing ability increases in the order DPSO > DESO > DMSO. Moreover, only DMSO and DESO have a real effect in preventing the heat-induced inactivation of the protein and their maximum heat-protective ability is reached when the DMSO and DESO amount is ⩾25% w/w. The sulfoxide ability to act as effective protective agents against the heat-induced inactivation was confirmed by the protein analysis. The enzymatic activity, as well as the SDS-PAGE analysis, suggested that DESO, having a low hydrophobic character and a great ability to stabilise the three-dimensional water structure, is the most heat-protective sulfoxide. An accurate evaluation of the heat-induced conformational changes of the lysozyme structure before and after sulfoxide addition was obtained by the analysis of the Raman spectra. The addition of DMSO or DESO in low concentration resulted to sensitively decrease the heat-induced structural modifications of the protein.

  3. Dimethyl Sulfoxide Induces Both Direct and Indirect Tau Hyperphosphorylation

    PubMed Central

    Julien, Carl; Marcouiller, François; Bretteville, Alexis; El Khoury, Noura B.; Baillargeon, Joanie; Hébert, Sébastien S.; Planel, Emmanuel

    2012-01-01

    Dimethyl sulfoxide (DMSO) is widely used as a solvent or vehicle for biological studies, and for treatment of specific disorders, including traumatic brain injury and several forms of amyloidosis. As Alzheimer’s disease (AD) brains are characterized by deposits of β-amyloid peptides, it has been suggested that DMSO could be used as a treatment for this devastating disease. AD brains are also characterized by aggregates of hyperphosphorylated tau protein, but the effect of DMSO on tau phosphorylation is unknown. We thus investigated the impact of DMSO on tau phosphorylation in vitro and in vivo. One hour following intraperitoneal administration of 1 or 2 ml/kg DMSO in mice, no change was observed in tau phosphorylation. However, at 4 ml/kg, tau was hyperphosphorylated at AT8 (Ser202/Thr205), PHF-1 (Ser396/Ser404) and AT180 (Thr231) epitopes. At this dose, we also noticed that the animals were hypothermic. When the mice were maintained normothermic, the effect of 4 ml/kg DMSO on tau hyperphosphorylation was prevented. On the other hand, in SH-SY5Y cells, 0.1% DMSO induced tau hyperphosphorylation at AT8 and AT180 phosphoepitopes in normothermic conditions. Globally, these findings demonstrate that DMSO can induce tau hyperphosphorylation indirectly via hypothermia in vivo, and directly in vitro. These data should caution researchers working with DMSO as it can induce artifactual results both in vivo and in vitro. PMID:22768202

  4. Photofragment energy distributions and dissociation pathways in dimethyl sulfoxide

    SciTech Connect

    Thorson, G.M.; Cheatum, C.M.; Coffey, M.J.; Fleming Crim, F.

    1999-06-01

    Photolysis of dimethyl sulfoxide in a molecular beam with 210 and 222 nm photons reveals the decomposition mechanism and energy disposal in the products. Using vacuum ultraviolet light and a time-of-flight spectrometer, we identify CH{sub 3} and CH{sub 3}SO as primary fragments and CH{sub 3} and SO as secondary fragments. From CH{sub 3} quantum yield measurements, we find that secondary decomposition is minor for 222 nm photolysis, occurring in only about 10{percent} of the fragments, but it increases to about 30{percent} in the 210 nm photolysis. Laser-induced fluorescence measurements on the B{sup 3}{Sigma}{sup {minus}}{l_arrow}X{sup 3}{Sigma}{sup {minus}} transition of SO in the 235 to 280 nm region determine the internal energy of that photoproduct. We compare our results to a simple statistical model that captures the essential features of the decomposition, predicting both the extent of secondary decomposition and the recoil energy of the primary and secondary methyl fragments. {copyright} {ital 1999 American Institute of Physics.}

  5. Chemical Instability of Dimethyl Sulfoxide in Lithium-Air Batteries.

    PubMed

    Kwabi, David G; Batcho, Thomas P; Amanchukwu, Chibueze V; Ortiz-Vitoriano, Nagore; Hammond, Paula; Thompson, Carl V; Shao-Horn, Yang

    2014-08-21

    Although dimethyl sulfoxide (DMSO) has emerged as a promising solvent for Li-air batteries, enabling reversible oxygen reduction and evolution (2Li + O2 ⇔ Li2O2), DMSO is well known to react with superoxide-like species, which are intermediates in the Li-O2 reaction, and LiOH has been detected upon discharge in addition to Li2O2. Here we show that toroidal Li2O2 particles formed upon discharge gradually convert into flake-like LiOH particles upon prolonged exposure to a DMSO-based electrolyte, and the amount of LiOH detectable increases with increasing rest time in the electrolyte. Such time-dependent electrode changes upon and after discharge are not typically monitored and can explain vastly different amounts of Li2O2 and LiOH reported in oxygen cathodes discharged in DMSO-based electrolytes. The formation of LiOH is attributable to the chemical reactivity of DMSO with Li2O2 and superoxide-like species, which is supported by our findings that commercial Li2O2 powder can decompose DMSO to DMSO2, and that the presence of KO2 accelerates both DMSO decomposition and conversion of Li2O2 into LiOH. PMID:26278088

  6. A new reliable method for dimethyl sulfoxide analysis in wastewater: dimethyl sulfoxide in Philadelphia's three water pollution control plants.

    PubMed

    Cheng, Xianhao; Peterkin, Earl

    2007-05-01

    A simple but reliable procedure was developed to analyze dimethyl sulfoxide (DMSO) in wastewater. The isotope DMSO_d6 was used as the internal standard to ensure accuracy. The DMSO was reduced with stannous chloride and measured as dimethyl sulfide (DMS) with purge-and-trap gas chromatography/mass spectrometry. The method detection limit was at the sub-microgram-per-milliliter level; precision, as measured by standard deviation, was better than +/- 0.5%; and the recoveries were between 95 and 105% at the level of 2 microg/mL. The procedure could use standard analytical instrumentation used for volatile organic compound analysis. A field study was conducted to validate the method and quantify DMSO concentration range in the three water pollution control plants (WPCPs) in the city of Philadelphia, Pennsylvania. Results showed that, when a local chemical facility discharged, DMSO concentration could be as high as 12 mg/L in the influent to a WPCP. This would lead to the formation of a toxic "canned corn" DMS odor during the treatment processes. PMID:17571849

  7. Permeation of dimethyl sulfoxide into articular cartilage at subzero temperatures.

    PubMed

    Zhang, Shao-Zhi; Yu, Xiao-Yi; Chen, Guang-Ming

    2012-03-01

    Osteochondral allografting has been proved to be a useful method to treat diseased or damaged areas of joint surfaces. Operational long-term stocks of grafts which supply a buffer between procurement and utilization would contribute to the commercialization or industrialization of this technology. Vitrification has been thought to be a promising method for successful preservation of articular cartilage (AC), but high concentration cryoprotectants (CPAs) are used which may cause high cellular toxicity. An effective way to reduce CPA toxicity is to increase CPA concentration gradually while the temperature is lowered. Understanding the mechanism of CPA permeation at subzero temperatures is important for designing the cryopreservation protocol. In this research, the permeation of dimethyl sulfoxide (Me(2)SO) in ovine AC at subzero temperatures was studied experimentally. Pretreated AC discs were exposed in Me(2)SO solutions for different time (0, 5, 15, 30, 50, 80, and 120 min) at three temperature levels (-10, -20, and -30 °C). The Me(2)SO concentration within the tissue was determined by ultraviolet (UV) spectrophotometry. The diffusion coefficients were estimated to be 0.85×10(-6), 0.48×10(-6), and 0.27×10(-6) cm(2)/s at -10, -20, and -30 °C, respectively, and the corresponding activation energy was 29.23 kJ/mol. Numerical simulation was performed to compare two Me(2)SO addition protocols, and the results demonstrated that the total loading duration could be effectively reduced with the knowledge of permeation kinetics. PMID:22374614

  8. Luminescence of Lanthanide-Dimethyl Sulfoxide Compound Solutions

    SciTech Connect

    Yao, Mingzhen; Li, Yuebin; Hossu, Marius; Joly, Alan G.; Liu, Zhongxin; Liu, Zuli; Chen, Wei

    2011-08-04

    Dimethyl sulfoxide (DMSO) has the ability to penetrate living tissues without causing significant damage. Of foremost importance to our understanding of the possible functions of DMSO in biological systems is its ability to replace some of the water molecules associated with the cellular constituents, or to affect the structure of the omnipresent water. Luminescence probes have been widely used for biological studies such as labeling, imaging and detection. Luminescence probes formed in DMSO may find new applications. Here, luminescence compounds formed by refluxing lanthanide nitrates of Ce, La, Tb, Yb, Nd, Gd and Eu in DMSO are reported and their luminescence properties investigated. Based on their luminescence spectral properties, the compounds can be classified into four classes. For compounds-I with Yb, Ce, and La, the excitation and emission spectra are very broad and their excitation or emission peaks are shifted to longer wavelengths when the monitored emission or excitation wavelength is longer . For compounds-II with Gd and Nd, both the excitation and emission spectra are very broad but their emission wavelengths change little at different excitation wavelengths. For Tb-DMSO as compound-III, both the typical emissions from the f - f transitions of Tb3+ and a broad emission at 445 nm are observed. At low temperatures of reaction, the f - f emissions are dominant, while at high temperatures such as 180 oC of reaction, the broad emission at 445 nm is dominant. For compound-IV with Eu-DMSO compounds, the dominant emissions are from the f - f transitions of Eu3+ and only a weak broad emission is observed, which is likely from the d - f transition of Eu2+ rather than from the metal to ligand charge transfer states.

  9. Determination of clindamycin and its metabolite clindamycin sulfoxide in diverse sewage samples.

    PubMed

    Oertel, Reinhard; Schubert, Sara; Mühlbauer, Viktoria; Büttner, Bozena; Marx, Conrad; Kirch, Wilhelm

    2014-10-01

    In a research project on risk management of harmful substances in water cycles, clindamycin and 12 further antibiotics were determined in different sewage samples. In contrast to other antibiotics, an increase of the clindamycin concentration in the final effluent in comparison to the influent of the sewage treatment plant (STP) was observed. A back transformation from the main metabolite clindamycin sulfoxide to clindamycin during the denitrification process has been discussed. Therefore, the concentration of this metabolite was measured additionally. Clindamycin sulfoxide was stable in the STP and the assumption of back transformation of the metabolite to clindamycin was confuted. To explain the increasing clindamycin concentration in the STP, the ratio of clindamycin sulfoxide to clindamycin was observed. The ratio increased in dry spells with concentrated samples and with long dwell time in the sewer system. A short hydraulic retention in waste water system and diluted samples in periods of extreme rainfall lead to a lower ratio of clindamycin sulfoxide to clindamycin concentration. A plausible explanation of this behavior could be that clindamycin was adsorbed strongly to a component of the sewage during this long residence time and in the STP, clindamycin was released. In the common sample preparation in the lab, clindamycin was not released. Measurements of clindamycin and clindamycin sulfoxide in the influent and effluent of STP is advised for sewage monitoring. PMID:24310902

  10. Determination of albendazole sulfoxide in human plasma by using liquid chromatography-tandem mass spectrometry.

    PubMed

    Saraner, Nihal; Özkan, Güler Yağmur; Güney, Berrak; Alkan, Erkin; Burul-Bozkurt, Nihan; Sağlam, Onursal; Fikirdeşici, Ezgi; Yıldırım, Mevlüt

    2016-06-01

    A rapid, simple and sensitive method was developed and validated using liquid chromatography-tandem mass spectrometry (LC-MS/MS) for determination of albendazole sulfoxide (ABZOX) in human plasma. The plasma samples were extracted by protein precipitation using albendazole sulfoxide-d3 as internal standard (IS). The chromatographic separation was performed on Waters Xbridge C18Column (100×4.6mm, 3.5μm) with a mobile phase consisting of ammonia solution, water and methanol at a flow rate of 0.70mL/min. ABZOX was detected and identified by mass spectrometry with electrospray ionization (ESI) in positive ion and multiple-reaction monitoring (MRM) mode. The method was linear in the range of 3-1500ng/mL for ABZOX. This method was successfully applied to the bioequivalence study in human plasma samples. PMID:27060508

  11. Inhibitory effects of combinations of oxytetracycline, dimethyl sulfoxide, and EDTA-tromethamine on Escherichia coli.

    PubMed

    Wooley, R E; Gilbert, J P; Shotts, E B

    1981-11-01

    Antibacterial activity against Escherichia coli was obtained with subminimal inhibitory concentrations of oxytetracycline (OTC) and EDTA-tromethamine. Inhibitory effects were not observed using combinations of dimethyl sulfoxide and OTC or dimethyl sulfoxide and EDTA-tromethamine. Neither EDTA-tromethamine nor OTC used alone was capable of the same degree of inhibition. Using a 2-dimensional Microtiter checkerboard technique, the inhibitory activity of these combinations was studied and isobolograms were plotted. A synergistic effect was seen with combinations of OTC and EDTA-tromethamine. Kinetic studies of microbial death, using subminimal inhibitory concentrations of these agents, confirmed these findings. PMID:6802044

  12. Synthesis of Sulfoximine Carbamates by Rhodium-Catalyzed Nitrene Transfer of Carbamates to Sulfoxides.

    PubMed

    Zenzola, Marina; Doran, Robert; Luisi, Renzo; Bull, James A

    2015-06-19

    Sulfoximines are of considerable interest for incorporation into medicinal compounds. A convenient synthesis of N-protected sulfoximines is achieved, under mild conditions, by rhodium-catalyzed transfer of carbamates to sulfoxides. The first examples of 4-membered thietane-oximines are prepared. Sulfoximines bearing Boc and Cbz groups are stable to further cross coupling reactions, and readily deprotected. This method may facilitate the preparation of NH-sulfoximines providing improved (global) deprotection strategies, which is illustrated in the synthesis of methionine sulfoxide (MSO). PMID:25989821

  13. N.m.r. studies of the conformation of analogues of methyl beta-lactoside in methyl sulfoxide-d6.

    PubMed

    Rivera-Sagredo, A; Jiménez-Barbero, J; Martín-Lomas, M

    1991-12-16

    The 1H- and 13C-n.m.r. spectra of solutions of methyl beta-lactoside (1), all of its monodeoxy derivatives (2, 3, 6-10), the 3-O-methyl derivative (4), and methyl 4-O-beta-D-galactopyranosyl-D-xylopyranoside (5) in methyl sulfoxide-d6 have been analysed. The n.O.e.'s and specific desheildings indicate similar distributions of low-energy conformers, comparable to those in aqueous solution. The major conformer has torsion angles phi H and psi H of 49 degrees and 5 degrees, respectively, with contributions of conformers with phi/psi 24 degrees/-59 degrees, 22 degrees/32 degrees, and 6 degrees/44 degrees. PMID:1816924

  14. Enantioselective sulfoxidation reaction catalyzed by a G-quadruplex DNA metalloenzyme.

    PubMed

    Cheng, Mingpan; Li, Yinghao; Zhou, Jun; Jia, Guoqing; Lu, Sheng-Mei; Yang, Yan; Li, Can

    2016-07-26

    Enantioselective sulfoxidation reaction is achieved for the first time by a DNA metalloenzyme assembled with the human telomeric G-quadruplex DNA and Cu(ii)-4,4'-bimethyl-2,2'-bipyridine complex, and the mixed G-quadruplex architectures are responsible for the catalytic enantioselectivity and activity. PMID:27359255

  15. Determination of the specific activities of methionine sulfoxide reductase A and B by capillary electrophoresis.

    PubMed

    Uthus, Eric O

    2010-06-01

    A capillary electrophoresis (CE) method for the determination of methionine sulfoxide reductase A and methionine sulfoxide reductase B activities in mouse liver is described. The method is based on detection of the 4-(dimethylamino)azobenzene-4'-sulfonyl derivative of l-methionine (dabsyl Met), the product of the enzymatic reactions when either dabsyl l-methionine S-sulfoxide or dabsyl l-methionine R-sulfoxide is used as a substrate. The method provides baseline resolution of the substrates and, therefore, can be used to easily determine the purity of the substrates. The method is rapid ( approximately 20min sample to sample), requires no column regeneration, and uses very small amounts of buffers. Separation was performed by using a 75-mum internal diameter polyimide-coated fused silica capillary (no inside coating) with 60cm total length (50cm to the detector window). Samples were separated at 22.5kV, and the separation buffer was 25mM KH(2)PO(4) (pH 8.0) containing 0.9ml of N-lauroylsarcosine (sodium salt, 30% [w/v] solution) per 100ml of buffer. Prior to use, the capillary was conditioned with the same buffer that also contained 25mM sodium dodecyl sulfate. The CE method is compared with high-performance liquid chromatography (HPLC) as determined by comparing results from measurements of hepatic enzyme activities in mice fed either deficient or adequate selenium. PMID:20167203

  16. Triclabendazole Sulfoxide Causes Stage-Dependent Embryolethality in Zebrafish and Mouse In Vitro

    PubMed Central

    Boix, Nuria; Teixido, Elisabet; Vila-Cejudo, Marta; Ortiz, Pedro; Ibáñez, Elena; Llobet, Juan M.; Barenys, Marta

    2015-01-01

    Background Fascioliasis and paragonimiasis are widespread foodborne trematode diseases, affecting millions of people in more than 75 countries. The treatment of choice for these parasitic diseases is based on triclabendazole, a benzimidazole derivative which has been suggested as a promising drug to treat pregnant women and children. However, at the moment, this drug is not approved for human use in most countries. Its potential adverse effects on embryonic development have been scarcely studied, and it has not been assigned a pregnancy category by the FDA. Thus, to help in the process of risk-benefit decision making upon triclabendazole treatment during pregnancy, a better characterization of its risks during gestation is needed. Methodology The zebrafish embryo test, a preimplantation and a postimplantation rodent whole embryo culture were used to investigate the potential embryotoxicity/teratogenicity of triclabendazole and its first metabolite triclabendazole sulfoxide. Albendazole and albendazole sulfoxide were included as positive controls. Principal Findings Triclabendazole was between 10 and 250 times less potent than albendazole in inducing dysmorphogenic effects in zebrafish or postimplantation rodent embryos, respectively. However, during the preimplantation period, both compounds, triclabendazole and triclabendazole sulfoxide, induced a dose-dependent embryolethal effect after only 24 h of exposure in rodent embryos and zebrafish (lowest observed adverse effect concentrations = 10 μM). Conclusions/Significance In humans, after ingestion of the recommended doses of triclabendazole to treat fascioliasis and paragonimiasis (10 mg/kg), the main compound found in plasma is triclabendazole sulfoxide (maximum concentration 38.6 μM), while triclabendazole concentrations are approximately 30 times lower (1.16 μM). From our results it can be concluded that triclabendazole, at concentrations of the same order of magnitude as the clinically relevant ones, does

  17. Identification of the sulfoxide functionality in protonated analytes via ion/molecule reactions in linear quadrupole ion trap mass spectrometry.

    PubMed

    Sheng, Huaming; Williams, Peggy E; Tang, Weijuan; Zhang, Minli; Kenttämaa, Hilkka I

    2014-09-01

    A mass spectrometric method utilizing gas-phase ion/molecule reactions of 2-methoxypropene (MOP) has been developed for the identification of the sulfoxide functionality in protonated analytes in a LQIT mass spectrometer. Protonated sulfoxide analytes react with MOP to yield an abundant addition product (corresponding to 37-99% of the product ions), which is accompanied by a much slower proton transfer. The total efficiency (percent of gas-phase collisions leading to products) of the reaction is moderate (3-14%). A variety of compounds with different functional groups, including sulfone, hydroxylamino, N-oxide, aniline, phenol, keto, ester, amino and hydroxy, were examined to probe the selectivity of this reaction. Most of the protonated compounds with proton affinities lower than that of MOP react mainly via proton transfer to MOP. The formation of adduct-MeOH ions was found to be characteristic for secondary N-hydroxylamines. N-Oxides formed abundant MOP adducts just like sulfoxides, but sulfoxides can be differentiated from N-oxides based on their high reaction efficiencies. The reaction was tested by using the anti-inflammatory drug sulindac (a sulfoxide) and its metabolite sulindac sulfone. The presence of a sulfoxide functionality in the drug but a sulfone functionality in the metabolite was readily demonstrated. The presence of other functionalities in addition to sulfoxide in the analytes was found not to influence the diagnostic reactivity. PMID:24968187

  18. Separability of SO[sub 2] from SO[sub 2]/N[sub 2] mixture through sulfoxide-modified poly(vinyl alcohol) and cellulose membranes

    SciTech Connect

    Imai, Kiyokazu; Shiomi, Tomoo; Tezuka, Yasuyuki; Itamochi, Hiroko; Miya, Masamitsu )

    1993-06-05

    Separability of SO[sub 2] from mixtures of SO[sub 2] and N[sub 2] gases was studied for membranes of poly(vinyl alcohol) (PVA) and cellulose modified with methyl, ethyl, t-butyl, and phenyl vinyl sulfoxides. Of these sulfoxide-modified polymers, the phenyl vinyl sulfoxide-modified PVA membranes were found to give the best separation of SO[sub 2]. In the phenyl vinyl sulfoxide-modified PVA membranes, the permeability coefficient of SO[sub 2] increased with sulfoxide content while separability of SO[sub 2] was maximum at a sulfoxide content of 23.5 mol %; the separation factor of SO[sub 2] was about 170 at this sulfoxide content.

  19. 1,1′:4′,1′′-Terphenyl-2′,5′-dicarb­oxy­lic acid dimethyl sulfoxide-d 6 disolvate

    PubMed Central

    Pop, Lucian C.; Preite, Marcelo; Manriquez, Juan Manuel; Vega, Andrés; Chavez, Ivonne

    2012-01-01

    The asymmetric unit of the title solvate, C20H14O4·2C2D6OS, contains half of the substituted terephthalic acid mol­ecule and one solvent mol­ecule. The centroid of the central benzene ring in the acid mol­ecule is coincident with a crystallographic inversion center. Neither the carboxyl nor the phenyl substituents are coplanar with the central aromatic ring, showing dihedral angles of 53.18 (11) and 47.83 (11)°, respectively. The dimethyl sulfoxide solvent mol­ecules are hydrogen bonded to the carb­oxy­lic acid groups. PMID:22606132

  20. Neuroprotective effects of (E)-3,4-diacetoxystyryl sulfone and sulfoxide derivatives in vitro models of Parkinson's disease.

    PubMed

    Ning, Xianling; Yuan, Mengmeng; Guo, Ying; Tian, Chao; Wang, Xiaowei; Zhang, Zhili; Liu, Junyi

    2016-06-01

    (E)-3,4-dihydroxystyryl aralkyl sulfones and sulfoxides have been reported as novel multifunctional neuroprotective agents in previous studies, which as phenolic compounds display antioxidative and antineuroinflammatory properties. To further enhance the neuroprotective effects and study structure-activity relationship of the derivatives, we synthesized their acetylated derivatives, (E)-3,4-diacetoxystyryl sulfones and sulfoxides, and examined their neuroprotective effects in vitro models of Parkinson's disease. The results indicate that (E)-3,4-diacetoxystyryl sulfones and sulfoxides can significantly inhibit kinds of neuron cell injury induced by toxicities, including 6-OHDA, NO, and H2O2. More important, they show higher antineuroinflammatory properties and similar antioxidative properties to corresponding un-acetylated compounds. Thus, we suggest that (E)-3,4-diacetoxystyryl sulfones and sulfoxides may have potential for the treatment of neurodegenerative disorders, especially Parkinson's disease. PMID:26176683

  1. High-quality life extension by the enzyme peptide methionine sulfoxide reductase

    PubMed Central

    Ruan, Hongyu; Tang, Xiang Dong; Chen, M.-L.; Joiner, M. A.; Sun, Guangrong; Brot, Nathan; Weissbach, Herbert; Heinemann, Stephen H.; Iverson, Linda; Wu, Chun-Fang; Hoshi, Toshinori

    2002-01-01

    Cumulative oxidative damages to cell constituents are considered to contribute to aging and age-related diseases. The enzyme peptide methionine sulfoxide reductase A (MSRA) catalyzes the repair of oxidized methionine in proteins by reducing methionine sulfoxide back to methionine. However, whether MSRA plays a role in the aging process is poorly understood. Here we report that overexpression of the msrA gene predominantly in the nervous system markedly extends the lifespan of the fruit fly Drosophila. The MSRA transgenic animals are more resistant to paraquat-induced oxidative stress, and the onset of senescence-induced decline in the general activity level and reproductive capacity is delayed markedly. The results suggest that oxidative damage is an important determinant of lifespan, and MSRA may be important in increasing the lifespan in other organisms including humans. PMID:11867705

  2. Determination of the impurities in drug products containing montelukast and in silico/in vitro genotoxicological assessments of sulfoxide impurity.

    PubMed

    Emerce, Esra; Cok, Ismet; Degim, I Tuncer

    2015-10-14

    Impurities affecting safety, efficacy, and quality of pharmaceuticals are of increasing concern for regulatory agencies and pharmaceutical industries, since genotoxic impurities are understood to play important role in carcinogenesis. The study aimed to analyse impurities of montelukast chronically used in asthma theraphy and perform genotoxicological assessment considering regulatory approaches. Impurities (sulfoxide, cis-isomer, Michael adducts-I&II, methylketone, methylstyrene) were quantified using RP-HPLC analysis on commercial products available in Turkish market. For sulfoxide impurity, having no toxicity data and found to be above the qualification limit, in silico mutagenicity prediction analysis, miniaturized bacterial gene mutation test, mitotic index determination and in vitro chromosomal aberration test w/wo metabolic activation system were conducted. In the analysis of different batches of 20 commercial drug products from 11 companies, only sulfoxide impurity exceeded qualification limit in pediatric tablets from 2 companies and in adult tablets from 7 companies. Leadscope and ToxTree programs predicted sulfoxide impurity as nonmutagenic. It was also found to be nonmutagenic in Ames MPF Penta I assay. Sulfoxide impurity was dose-dependent cytotoxic in human peripheral lymphocytes, however, it was found to be nongenotoxic. It was concluded that sulfoxide impurity should be considered as nonmutagenic and can be classified as ordinary impurity according to guidelines. PMID:26205398

  3. Thiol–disulfide exchange is involved in the catalytic mechanism of peptide methionine sulfoxide reductase

    PubMed Central

    Lowther, W. Todd; Brot, Nathan; Weissbach, Herbert; Honek, John F.; Matthews, Brian W.

    2000-01-01

    Peptide methionine sulfoxide reductase (MsrA; EC 1.8.4.6) reverses the inactivation of many proteins due to the oxidation of critical methionine residues by reducing methionine sulfoxide, Met(O), to methionine. MsrA activity is independent of bound metal and cofactors but does require reducing equivalents from either DTT or a thioredoxin-regenerating system. In an effort to understand these observations, the four cysteine residues of bovine MsrA were mutated to serine in a series of permutations. An analysis of the enzymatic activity of the variants and their free sulfhydryl states by mass spectrometry revealed that thiol–disulfide exchange occurs during catalysis. In particular, the strictly conserved Cys-72 was found to be essential for activity and could form disulfide bonds, only upon incubation with substrate, with either Cys-218 or Cys-227, located at the C terminus. The significantly decreased activity of the Cys-218 and Cys-227 variants in the presence of thioredoxin suggested that these residues shuttle reducing equivalents from thioredoxin to the active site. A reaction mechanism based on the known reactivities of thiols with sulfoxides and the available data for MsrA was formulated. In this scheme, Cys-72 acts as a nucleophile and attacks the sulfur atom of the sulfoxide moiety, leading to the formation of a covalent, tetracoordinate intermediate. Collapse of the intermediate is facilitated by proton transfer and the concomitant attack of Cys-218 on Cys-72, leading to the formation of a disulfide bond. The active site is returned to the reduced state for another round of catalysis by a series of thiol—disulfide exchange reactions via Cys-227, DTT, or thioredoxin. PMID:10841552

  4. Mutagenicity of the Cysteine S-Conjugate Sulfoxides of Trichloroethylene and Tetrachloroethylene in the Ames Test

    PubMed Central

    Irving, Roy M.; Elfarra, Adnan A.

    2013-01-01

    The nephrotoxicity and nephrocarcinogenicity of trichloroethylene (TCE) and tetrachloroethylene (PCE) are believed to be mediated primarily through the cysteine S-conjugate β-lyase-dependent bioactivation of the corresponding cysteine S-conjugate metabolites S-(1,2-dichlorovinyl)-L-cysteine (DCVC) and S-(1,2,2-trichlorovinyl)-L-cysteine (TCVC), respectively. DCVC and TCVC have previously been demonstrated to be mutagenic by the Ames Salmonella mutagenicity assay, and reduction in mutagenicity was observed upon treatment with the β-lyase inhibitor aminooxyacetic acid (AOAA). Because DCVC and TCVC can also be bioactivated through sulfoxidation to yield the potent nephrotoxicants S-(1,2-dichlorovinyl)-L-cysteine sulfoxide (DCVCS) and S-(1,2,2-trichlorovinyl)-L-cysteine sulfoxide (TCVCS), respectively, the mutagenic potential of these two sulfoxides was investigated using the Ames S. typhimuriumTA100 mutagenicity assay. The results show both DCVCS and TCVCS were mutagenic, and TCVCS exhibited 3-fold higher mutagenicity than DCVCS. However, DCVCS and TCVCS mutagenic activity was approximately 700-fold and 30-fold lower than DCVC and TCVC, respectively. DCVC and DCVCS appeared to induce toxicity in TA100, as evidenced by increased microcolony formation and decreased mutant frequency above threshold concentrations. TCVC and TCVCS were not toxic in TA100. The toxic effects of DCVC limited the sensitivity of TA100 to DCVC mutagenic effects and rendered it difficult to investigate the effects of AOAA on DCVC mutagenic activity. Collectively, these results suggest that DCVCS and TCVCS exerted a definite but weak mutagenicity in the TA100 strain. Therefore, despite their potent nephrotoxicity, DCVCS and TCVCS are not likely to play a major role in DCVC or TCVC mutagenicity in this strain. PMID:23416178

  5. Synthesis and Antiproliferative Activities of Benzimidazole-Based Sulfide and Sulfoxide Derivatives.

    PubMed

    Gaballah, Samir T; El-Nezhawy, Ahmed O H; Amer, Hassan; Ali, Mamdouh Moawad; Mahmoud, Abeer Essam El-Din; Hofinger-Horvath, Andreas

    2016-01-01

    The design, synthesis, and in vitro antiproliferative activity of a novel series of sulfide (4a-i) and sulfoxide (5a-h) derivatives of benzimidazole, in which different aromatic and heteroaromatic acetamides are linked to benzimidazole via sulfide (4a-i) and sulfoxide (5a-h) linker, are reported and the structure-activity relationship is discussed. The new derivatives were prepared by coupling 2-(mercaptomethyl)benzimidazole with 2-bromo-N-(substituted) acetamides in dry acetone in the presence of anhydrous potassium carbonate. With very few exceptions, all of the synthesized compounds showed varying antiprolific activities against HepG2, MCF-7, and A549 cell lines. Compound 5a was very similar in potency to doxorubicin as an anticancer drug, with IC50 values 4.1 ± 0.5, 4.1 ± 0.5, and 5.0 ± 0.6 µg/mL versus 4.2 ± 0.5, 4.9 ± 0.6, and 6.1 ± 0.6 µg/mL against HepG2, MCF-7, and A549 cell lines, respectively. In contrast, none of the compounds showed activity against human prostate PC3 cancer cells. Additionally, the sulfoxide derivatives were more potent than the corresponding sulfides. PMID:27110495

  6. Synthesis and Antiproliferative Activities of Benzimidazole-Based Sulfide and Sulfoxide Derivatives

    PubMed Central

    Gaballah, Samir T.; El-Nezhawy, Ahmed O. H.; Amer, Hassan; Ali, Mamdouh Moawad; Mahmoud, Abeer Essam El-Din; Hofinger-Horvath, Andreas

    2016-01-01

    The design, synthesis, and in vitro antiproliferative activity of a novel series of sulfide (4a–i) and sulfoxide (5a–h) derivatives of benzimidazole, in which different aromatic and heteroaromatic acetamides are linked to benzimidazole via sulfide (4a–i) and sulfoxide (5a–h) linker, are reported and the structure-activity relationship is discussed. The new derivatives were prepared by coupling 2-(mercaptomethyl)benzimidazole with 2-bromo-N-(substituted) acetamides in dry acetone in the presence of anhydrous potassium carbonate. With very few exceptions, all of the synthesized compounds showed varying antiprolific activities against HepG2, MCF-7, and A549 cell lines. Compound 5a was very similar in potency to doxorubicin as an anticancer drug, with IC50 values 4.1 ± 0.5, 4.1 ± 0.5, and 5.0 ± 0.6 µg/mL versus 4.2 ± 0.5, 4.9 ± 0.6, and 6.1 ± 0.6 µg/mL against HepG2, MCF-7, and A549 cell lines, respectively. In contrast, none of the compounds showed activity against human prostate PC3 cancer cells. Additionally, the sulfoxide derivatives were more potent than the corresponding sulfides. PMID:27110495

  7. Overexpression of methionine-R-sulfoxide reductases has no influence on fruit fly aging

    PubMed Central

    Shchedrina, Valentina A.; Vorbrüggen, Gerd; Cheon Lee, Byung; Kim, Hwa-Young; Kabil, Hadise; Harshman, Lawrence G.; Gladyshev, Vadim N.

    2009-01-01

    Methionine sulfoxide reductases (Msrs) are enzymes that repair oxidized methionine residues in proteins. This function implicated Msrs in antioxidant defense and the regulation of aging. There are two known Msr types in animals: MsrA specific for the reduction of methionine-S-sulfoxide, and MsrB that catalyzes the reduction of methionine-R-sulfoxide. In a previous study, overexpression of MsrA in the nervous system of Drosophila was found to extend lifespan by 70%. Overexpression of MsrA in yeast also extended lifespan, whereas MsrB overexpression did so only under calorie restriction conditions. The effect of MsrB overexpression on lifespan has not yet been characterized in any animal model systems. Here, the GAL4-UAS binary system was used to drive overexpression of cytosolic Drosophila MsrB and mitochondrial mouse MsrB2 in whole body, fatbody, and the nervous system of flies. In contrast to MsrA, MsrB overexpression had no consistent effect on the lifespan of fruit flies on both corn meal and sugar yeast diets. Physical activity, fecundity, and stress resistance were also similar in MsrB-overexpressing and control flies. Thus, MsrA and MsrB, the two proteins with identical function in antioxidant protein repair, have different effects on aging in fruit flies. PMID:19409408

  8. Corynebacterium diphtheriae Methionine Sulfoxide Reductase A Exploits a Unique Mycothiol Redox Relay Mechanism*

    PubMed Central

    Tossounian, Maria-Armineh; Pedre, Brandán; Wahni, Khadija; Erdogan, Huriye; Vertommen, Didier; Van Molle, Inge; Messens, Joris

    2015-01-01

    Methionine sulfoxide reductases are conserved enzymes that reduce oxidized methionines in proteins and play a pivotal role in cellular redox signaling. We have unraveled the redox relay mechanisms of methionine sulfoxide reductase A of the pathogen Corynebacterium diphtheriae (Cd-MsrA) and shown that this enzyme is coupled to two independent redox relay pathways. Steady-state kinetics combined with mass spectrometry of Cd-MsrA mutants give a view of the essential cysteine residues for catalysis. Cd-MsrA combines a nucleophilic cysteine sulfenylation reaction with an intramolecular disulfide bond cascade linked to the thioredoxin pathway. Within this cascade, the oxidative equivalents are transferred to the surface of the protein while releasing the reduced substrate. Alternatively, MsrA catalyzes methionine sulfoxide reduction linked to the mycothiol/mycoredoxin-1 pathway. After the nucleophilic cysteine sulfenylation reaction, MsrA forms a mixed disulfide with mycothiol, which is transferred via a thiol disulfide relay mechanism to a second cysteine for reduction by mycoredoxin-1. With x-ray crystallography, we visualize two essential intermediates of the thioredoxin relay mechanism and a cacodylate molecule mimicking the substrate interactions in the active site. The interplay of both redox pathways in redox signaling regulation forms the basis for further research into the oxidative stress response of this pathogen. PMID:25752606

  9. Experimental and theoretical proton affinities of methionine, methionine sulfoxide and their N- and C-terminal derivatives

    NASA Astrophysics Data System (ADS)

    Lioe, Hadi; O'Hair, Richard A. J.; Gronert, Scott; Austin, Allen; Reid, Gavin E.

    2007-11-01

    The proton affinities of methionine, methionine sulfoxide and their derivatives (methionine methyl ester, methionine sulfoxide methyl ester, methionine methyl amide, methionine sulfoxide methyl amide, N-acetyl methionine, N-acetyl methionine sulfoxide, N-acetyl methionine methyl ester, N-acetyl methionine sulfoxide methyl ester, N-acetyl methionine methyl amide and N-acetyl methionine sulfoxide methyl amide) were experimentally determined using the kinetic method, in which proton bound dimers formed via electrospray ionization (ESI) were subjected to collision induced dissociation (CID) in a triple quadrupole mass spectrometer. In addition, theoretical calculations carried out at the MP2/6-311 + G(2d,p)//B3LYP/6-31 + G(d,p) level of theory to determine the global minima of the neutral and protonated species of all derivatives studied, were used to predict theoretical proton affinities. The density function theory calculations not only support the experimental proton affinities, but also provide structural insights into the types of hydrogen bonding that stabilize the neutral and protonated methionine or methionine sulfoxide derivatives. Comparison of the proton affinities of the various methionine and methionine sulfoxide derivatives reveals that: (i) oxidation of methionine derivatives to methionine sulfoxide derivatives results in an increase in proton affinity due to higher intrinsic proton affinity and an increase in the ring size formed through charge complexation of the sulfoxide group, which allows more efficient hydrogen bonding compared to the sulfide group; (ii) C-terminal modification by methyl esterification or methyl amidation increases the proton affinity in the order of methyl amide > methyl ester > carboxylic acid due to improved charge stabilization; (iii) N-terminal modification by N-acetylation decreases proton affinity of the derivatives due to lower intrinsic proton affinity of the N-acetyl group as well as due to stabilization of the attached

  10. Functioning methionine sulfoxide reductases A and B are present in human epidermal melanocytes in the cytosol and in the nucleus

    SciTech Connect

    Schallreuter, Karin U.; Chavan, Bhaven; Gillbro, Johanna M.

    2006-03-31

    Oxidation of methionine residues by reactive oxygen (ROS) in protein structures leads to the formation of methionine sulfoxide which can consequently lead to a plethora of impaired functionality. The generation of methionine sulfoxide yields ultimately a diastereomeric mixture of the S and R sulfoxides. So far two distinct enzyme families have been identified. MSRA reduces methionine S-sulfoxide, while MSRB reduces the R-diastereomer. It has been shown that these enzymes are involved in regulation of protein function and in elimination of ROS via reversible methionine formation besides protein repair. Importantly, both enzymes require coupling to the NADPH/thioredoxin reductase/thioredoxin electron donor system. In this report, we show for First time the expression and function of both sulfoxide reductases together with thioredoxin reductase in the cytosol as well as in the nucleus of epidermal melanocytes which are especially sensitive to ROS. Since this cell resides in the basal layer of the epidermis and its numbers and functions are reduced upon ageing and for instance also in depigmentation processes, we believe that this discovery adds an intricate repair mechanism to melanocyte homeostasis and survival.

  11. Sulfoxide stimulation of chondrogenesis in limb mesenchyme is accompanied by an increase in type II collagen enhancer activity

    SciTech Connect

    Horton, W.E. Jr.; Higginbotham, J.D. )

    1991-05-01

    We have utilized a modification of the limb bud mesenchyme micromass culture system to screen compounds that might stimulate chondrogenesis. Two compounds in the sulfoxide family (methylphenylsulfoxide and p-chlorophenyl methyl sulfoxide) were stimulatory at 10(-2) M and 10(-3) M, respectively; whereas other sulfoxides and organic solvents were not active at these concentrations. In addition, specific growth factors (basic FGF, IGF-I, IGF-II) were not chondroinductive at concentrations that are active in other cell systems. Both sulfoxide compounds stimulated cartilage nodule formation, ({sup 35}S)sulfate incorporation, and activity of the regulatory sequences of the collagen II gene. In contrast, transforming growth factor beta-1 (10 ng/ml) stimulated sulfate incorporation but produced only a diffuse deposition of cartilage matrix and reduced the ability of the cells to utilize the regulatory sequences of the collagen II gene. The sulfoxides appear to promote the differentiation of limb bud cells to chondrocytes and thus exhibit chondroinductive activity.

  12. Three-body dissociations: The photodissociation of dimethyl sulfoxide at 193 nm

    SciTech Connect

    Blank, D.A.; North, S.W.; Stranges, D.

    1997-04-01

    When a molecule with two equivalent chemical bonds is excited above the threshold for dissociation of both bonds, how the rupture of the two bonds is temporally coupled becomes a salient question. Following absorption at 193 nm dimethyl sulfoxide (CH{sub 3}SOCH{sub 3}) contains enough energy to rupture both C-S bonds. This can happen in a stepwise (reaction 1) or concerted (reaction 2) fashion where the authors use rotation of the SOCH{sub 3} intermediate prior to dissociation to define a stepwise dissociation: (1) CH{sub 3}SOCH{sub 3} {r_arrow} 2CH{sub 3} + SO; (2a) CH{sub 3}SOCH{sub 3} {r_arrow} CH{sub 3} + SOCH{sub 3}; and (2b) SOCH{sub 3} {r_arrow} SO + CH{sub 3}. Recently, the dissociation of dimethyl sulfoxide following absorption at 193 nm was suggested to involve simultaneous cleavage of both C-S bonds on an excited electronic surface. This conclusion was inferred from laser induced fluorescence (LIF) and resonant multiphoton ionization (2+1 REMPI) measurements of the internal energy content in the CH{sub 3} and SO photoproducts and a near unity quantum yield measured for SO. Since this type of concerted three body dissociation is very interesting and a rather rare event in photodissociation dynamics, the authors chose to investigate this system using the technique of photofragment translational spectroscopy at beamline 9.0.2.1. The soft photoionization provided by the VUV undulator radiation allowed the authors to probe the SOCH{sub 3} intermediate which had not been previously observed and provided good evidence that the dissociation of dimethyl sulfoxide primarily proceeds via a two step dissociation, reaction 2.

  13. A Methionine Residue Promotes Hyperoxidation of the Catalytic Cysteine of Mouse Methionine Sulfoxide Reductase A.

    PubMed

    Kim, Geumsoo; Levine, Rodney L

    2016-06-28

    Methionine sulfoxide reductase A (msrA) reduces methionine sulfoxide in proteins back to methionine. Its catalytic cysteine (Cys72-SH) has a low pKa that facilitates oxidation by methionine sulfoxide to cysteine sulfenic acid. If the catalytic cycle proceeds efficiently, the sulfenic acid is reduced back to cysteine at the expense of thioredoxin. However, the sulfenic acid is vulnerable to "irreversible" oxidation to cysteine sulfinic acid that inactivates msrA (hyperoxidation). We observed that human msrA is resistant to hyperoxidation while mouse msrA is readily hyperoxidized by micromolar concentrations of hydrogen peroxide. We investigated the basis of this difference in susceptibility to hyperoxidation and established that it is controlled by the presence or absence of a Met residue in the carboxyl-terminal domain of the enzyme, Met229. This residue is Val in human msrA, and when it was mutated to Met, human msrA became sensitive to hyperoxidation. Conversely, mouse msrA was rendered insensitive to hyperoxidation when Met229 was mutated to Val or one of five other residues. Positioning of the methionine at residue 229 is not critical, as hyperoxidation occurred as long as the methionine was located within the group of 14 carboxyl-terminal residues. The carboxyl domain of msrA is known to be flexible and to have access to the active site, and Met residues are known to form stable, noncovalent bonds with aromatic residues through interaction of the sulfur atom with the aromatic ring. We propose that Met229 forms such a bond with Trp74 at the active site, preventing formation of a protective sulfenylamide with Cys72 sulfenic acid. As a consequence, the sulfenic acid is available for facile, irreversible oxidation to cysteine sulfinic acid. PMID:27259041

  14. Increased Catalytic Efficiency Following Gene Fusion of Bifunctional Methionine Sulfoxide Reductase Enzymes from Shewanella oneidensis

    SciTech Connect

    Chen, Baowei; Markillie, Lye Meng; Xiong, Yijia; Mayer, M. Uljana; Squier, Thomas C.

    2007-11-11

    Methionine sulfoxide reductase enzymes MsrA and MsrB have complementary stereospecificies that respectively reduce the S- and R-stereoisomers of methionine sulfoxide (MetSO), and together function as critical antioxidant enzymes. In some pathogenic and metal reducing bacteria these genes are fused to form a bifunctional methionine sulfoxide reductase (i.e., MsrBA) enzyme. To investigate the impact of gene fusion on the substrate specificity and catalytic activities of Msr, we have cloned and expressed the MsrBA enzyme from Shewanella oneidensis, a metal reducing bacterium and fish pathogen. For comparison, we also cloned and expressed the wild-type MsrA enzyme and a genetically engineered MsrB protein. We report that MsrBA is able to completely reduce (i.e., repair) MetSO in the calcium regulatory protein calmodulin; in comparison only partial repair is observed using both MsrA and MsrB enzymes together at 25 °C. MsrBA has a twenty-fold enhanced rate of repair for MetSO in proteins in comparison with the individual MsrA or MsrB enzymes alone and respective 14- and 50-fold increases in catalytic efficiency (i.e., kcat/KM). In comparison, MsrBA and MsrA have similar catalytic efficiencies when free MetSO is used as a substrate. These results indicate that the individual domains within bifunctional MsrBA work cooperatively to selectively recognize and reduce MetSO in highly oxidized proteins. The enhanced catalytic activity of MsrBA against oxidized proteins and its common expression in bacterial pathogens is consistent with an important role for this enzyme activity in promoting bacterial survival under highly oxidizing conditions associated with pathogenesis or bioremediation.

  15. Effect of dimethyl sulfoxide addition on ultrasonic degradation of methylene blue

    NASA Astrophysics Data System (ADS)

    Shimakage, Kaho; Kobayashi, Daisuke; Naya, Masakazu; Matsumoto, Hideyuki; Shimada, Yuichiro; Otake, Katsuto; Shono, Atsushi

    2016-07-01

    The ultrasonic degradation of methylene blue was carried out in the absence and presence of dimethyl sulfoxide (DMSO) as a radical scavenger for various frequencies, and the effects of DMSO addition on the degradation rate constant estimated by assuming first-order kinetics were investigated. The degradation reaction rate decreased with DMSO addition, and hydroxyl radicals were observed to play important roles in the degradation of methylene blue. However, the degradation reaction did not stop with DMSO addition, and the degradation rate constant in the presence of DMSO was not affected by ultrasonic frequency.

  16. Crystal structure of hexa-kis-(dimethyl sulfoxide-κO)manganese(II) diiodide.

    PubMed

    Glatz, Mathias; Schroffenegger, Martina; Weil, Matthias; Kirchner, Karl

    2016-07-01

    The asymmetric unit of the title salt, [Mn(C2H6OS)6]I2, consists of one Mn(II) ion, six O-bound dimethyl sulfoxide (DMSO) ligands and two I(-) counter-anions. The isolated complex cations have an octa-hedral configuration and are grouped in hexa-gonally arranged rows extending parallel to [100]. The two I(-) anions are located between the rows and are linked to the cations through two weak C-H⋯I inter-actions. PMID:27555928

  17. Di-μ-chlorido-bis­[chloridobis(dimethyl sulfoxide)dioxidouranium(VI)

    PubMed Central

    Takao, Koichiro; Ikeda, Yasuhisa

    2008-01-01

    In the crystal structure of the title compound, [U2Cl4O4(C2H6OS)4], the compound has a centrosymmetric dimeric structure bridged by two chloride anions. Each UVI atom is seven-coordinate in a penta­gonal-bipyramidal geometry. In the equatorial plane of the uranyl unit there are two O atoms from non-adjacent dimethyl sulfoxides and three chloride ions (of which two chlorides are bridging). The compound is of inter­est as an anhydrous starting material of the uran­yl(VI) ion. PMID:21200466

  18. Photochromic ruthenium sulfoxide complexes: evidence for isomerization through a conical intersection.

    PubMed

    McClure, Beth Anne; Mockus, Nicholas V; Butcher, Dennis P; Lutterman, Daniel A; Turro, Claudia; Petersen, Jeffrey L; Rack, Jeffrey J

    2009-09-01

    The complexes [Ru(bpy)(2)(OS)](PF(6)) and [Ru(bpy)(2)(OSO)](PF(6)), where bpy is 2,2'-bipyridine, OS is 2-methylthiobenzoate, and OSO is 2-methylsulfinylbenzoate, have been studied. The electrochemical and photochemical reactivity of [Ru(bpy)(2)(OSO)](+) is consistent with an isomerization of the bound sulfoxide from S-bonded (S-) to O-bonded (O-) following irradiation or electrochemical oxidation. Charge transfer excitation of [Ru(bpy)(2)(OSO)](+) in MeOH results in the appearance of two new metal-to-ligand charge transfer (MLCT) maxima at 355 and 496 nm, while the peak at 396 nm diminishes in intensity. The isomerization is reversible at room temperature in alcohol or propylene carbonate solution. In the absence of light, solutions of O-[Ru(bpy)(2)(OSO)](+) revert to S-[Ru(bpy)(2)(OSO)](+). Kinetic analysis reveals a biexponential decay with rate constants of 5.66(3) x 10(-4) s(-1) and 3.1(1) x 10(-5) s(-1). Cyclic voltammograms of S-[Ru(bpy)(2)(OSO)](+) are consistent with electron-transfer-triggered isomerization of the sulfoxide. Analysis of these voltammograms reveal E(S)(o)' = 0.86 V and E(O)(o)' = 0.49 V versus Ag/Ag(+) for the S- and O-bonded Ru(3+/2+) couples, respectively, in propylene carbonate. We found k(S-->O) = 0.090(15) s(-1) in propylene carbonate and k(S-->O) = 0.11(3) s(-1) in acetonitrile on Ru(III), which is considerably slower than has been reported for other sulfoxide isomerizations on ruthenium polypyridyl complexes following oxidation. The photoisomerization quantum yield (Phi(S-->O) = 0.45, methanol) is quite large, indicating a rapid excited state isomerization rate constant. The kinetic trace at 500 nm is monoexponential with tau = 150 ps, which is assigned to the excited S-->O isomerization rate. There is no spectroscopic or kinetic evidence for an O-bonded (3)MLCT excited state in the spectral evolution of S-[Ru(bpy)(2)(OSO)](+) to O-[Ru(bpy)(2)(OSO)](+). Thus, isomerization occurs nonadiabatically from an S-bonded (or eta(2

  19. Transfer of Electrophilic NH Using Convenient Sources of Ammonia: Direct Synthesis of NH Sulfoximines from Sulfoxides.

    PubMed

    Zenzola, Marina; Doran, Robert; Degennaro, Leonardo; Luisi, Renzo; Bull, James A

    2016-06-13

    A new system for NH transfer is developed for the preparation of sulfoximines, which are emerging as valuable motifs for drug discovery. The protocol employs readily available sources of nitrogen without the requirement for either preactivation or for metal catalysts. Mixing ammonium salts with diacetoxyiodobenzene directly converts sulfoxides into sulfoximines. This report describes the first example of using of ammonia sources with diacetoxyiodobenzene to generate an electrophilic nitrogen center. Control and mechanistic studies suggest a short-lived electrophilic intermediate, which is likely to be PhINH or PhIN(+) . PMID:27126053

  20. Crystal structure of hexa­kis­(dimethyl sulfoxide-κO)manganese(II) diiodide

    PubMed Central

    Glatz, Mathias; Schroffenegger, Martina; Weil, Matthias; Kirchner, Karl

    2016-01-01

    The asymmetric unit of the title salt, [Mn(C2H6OS)6]I2, consists of one MnII ion, six O-bound dimethyl sulfoxide (DMSO) ligands and two I− counter-anions. The isolated complex cations have an octa­hedral configuration and are grouped in hexa­gonally arranged rows extending parallel to [100]. The two I− anions are located between the rows and are linked to the cations through two weak C—H⋯I inter­actions. PMID:27555928

  1. Dimethyl Sulfoxide Protects Escherichia coli from Rapid Antimicrobial-Mediated Killing.

    PubMed

    Mi, Hongfei; Wang, Dai; Xue, Yunxin; Zhang, Zhi; Niu, Jianjun; Hong, Yuzhi; Drlica, Karl; Zhao, Xilin

    2016-08-01

    The contribution of reactive oxygen species (ROS) to antimicrobial lethality was examined by treating Escherichia coli with dimethyl sulfoxide (DMSO), an antioxidant solvent frequently used in antimicrobial studies. DMSO inhibited killing by ampicillin, kanamycin, and two quinolones and had little effect on MICs. DMSO-mediated protection correlated with decreased ROS accumulation and provided evidence for ROS-mediated programmed cell death. These data support the contribution of ROS to antimicrobial lethality and suggest caution when using DMSO-dissolved antimicrobials for short-time killing assays. PMID:27246776

  2. Cyclic sulfoxides-garlicnins K1, K2, and H1-extracted from Allium sativum.

    PubMed

    Nohara, Toshihiro; Fujiwara, Yukio; Komota, Yusuke; Kondo, Yoshihiko; Saku, Taiki; Yamaguchi, Koki; Komohara, Yoshihiro; Takeya, Motohiro

    2015-01-01

    Newly identified cyclic sulfoxides-garlicnins K1 (1), K2 (2), and H1 (3)-were isolated from the acetone extracts of the bulbs of garlic, Allium sativum. Garlicnin H1 (3) demonstrated potential to suppress tumor cell proliferation by regulating macrophage activation. The structures of garlicnins K1 and K2, 3,4-dimethyl-5-allyl-tetrahydrothiophen-2-one-S-oxides, and the structure of garlicnin H1, 3-carboxy-3-hydroxy-4-methyl-5-allylsulfoxide-tetrahydrothiophen-2-(ethane-1,2-diol)-S-oxide were characterized by spectroscopic analysis. PMID:25748782

  3. A QSPR study on the solvent-induced frequency shifts of acetone and dimethyl sulfoxide in organic solvents

    NASA Astrophysics Data System (ADS)

    Ou, Yu Heng; Chang, Chia Ming; Chen, Ying Shao

    2016-06-01

    In this study, solvent-induced frequency shifts (SIFS) in the infrared spectrum of acetone and dimethyl sulfoxide in organic solvents were investigated by using four types of quantum-chemical reactivity descriptors. The results showed that the SIFS of acetone is mainly affected by the electron-acceptance chemical potential and the maximum nucleophilic condensed local softness of organic solvents, which represent the electron flow and the polarization between acetone and solvent molecules. On the other hand, the SIFS of dimethyl sulfoxide changes with the maximum positive charge of hydrogen atom and the inverse of apolar surface area of solvent molecules, showing that the electrostatic and hydrophilic interactions are main mechanisms between dimethyl sulfoxide and solvent molecules. The introduction of the four-element theory model-based quantitative structure-property relationship approach improved the assessing quality and provided a basis for interpreting the solute-solvent interactions.

  4. A QSPR study on the solvent-induced frequency shifts of acetone and dimethyl sulfoxide in organic solvents.

    PubMed

    Ou, Yu Heng; Chang, Chia Ming; Chen, Ying Shao

    2016-06-01

    In this study, solvent-induced frequency shifts (SIFS) in the infrared spectrum of acetone and dimethyl sulfoxide in organic solvents were investigated by using four types of quantum-chemical reactivity descriptors. The results showed that the SIFS of acetone is mainly affected by the electron-acceptance chemical potential and the maximum nucleophilic condensed local softness of organic solvents, which represent the electron flow and the polarization between acetone and solvent molecules. On the other hand, the SIFS of dimethyl sulfoxide changes with the maximum positive charge of hydrogen atom and the inverse of apolar surface area of solvent molecules, showing that the electrostatic and hydrophilic interactions are main mechanisms between dimethyl sulfoxide and solvent molecules. The introduction of the four-element theory model-based quantitative structure-property relationship approach improved the assessing quality and provided a basis for interpreting the solute-solvent interactions. PMID:26994584

  5. One-Pot Sulfoxide Synthesis Exploiting a Sulfinyl-Dication Equivalent Generated from a DABSO/Trimethylsilyl Chloride Sequence.

    PubMed

    Lenstra, Danny C; Vedovato, Vincent; Ferrer Flegeau, Emmanuel; Maydom, Jonathan; Willis, Michael C

    2016-05-01

    A one-pot process for the synthesis of unsymmetrical sulfoxides using organometallic nucleophiles is described. Sulfur dioxide, delivered from the surrogate DABSO (DABCO-bis(sulfur dioxide)), acts as the initial electrophile and combines with the first organometallic reagent to generate a sulfinate intermediate. In situ conversion of the sulfinate to a sulfinate silyl ester, using TMS-Cl (trimethylsilyl chloride), generates a second electrophile, allowing addition of a second organometallic reagent. Organolithium or Grignard reagents can be employed, delivering sulfoxides in good to excellent yields. PMID:27082825

  6. A DFT-D study on the electronic and photophysical properties of ruthenium (II) complex with a chelating sulfoxide group

    NASA Astrophysics Data System (ADS)

    Li, Huifang; Zhang, Lisheng; Lin, Hui; Fan, Xiaolin

    2014-06-01

    Electronic and photophysical properties of [Ru(bpy)2(OSO)]+ (bpy = 2,2‧-bipyridine; OSO = methylsulfinylbenzoate) were examined theoretically to better understand the differences between S- and O-linked ruthenium sulfoxide complexes. It is found that the strength of Ru-O1 linkage is significantly larger than that of Ru-S linkage, which makes the charge transfer amount from surrounding ligands to central Ru decreased. The energy gap is closed due to the highest occupied molecular orbital energy increases to a larger extent than the lowest unoccupied molecular orbital energy. Thereby, red shifted absorption and emission maxima in such photochromic ruthenium sulfoxide complexes can be explained.

  7. Molecular interactions between benzimide trichloride (Hoechst 33258) and DNA in dimethyl sulfoxide aqueous solutions, according to spectroscopy data

    NASA Astrophysics Data System (ADS)

    Amirbekyan, K. Yu.; Antonyan, A. P.; Vardevanyan, P. O.; Markarian, Sh. A.

    2013-12-01

    Interaction between benzimide (Hoechst 33258, H33258) and calf thymus DNA in aqueous dimethyl sulfoxide is investigated by means of UV-Vis and fluorescence spectroscopy at a constant ratio ( r) of the number of H33258 molecules and DNA base pairs. Melting curves of the DNA-H33258 complex are obtained from the temperature dependences of the normalized optical density and fluorescence intensity, and the melting temperatures of the complex are determined. It is shown that adding dimethyl sulfoxide (DMSO) lowers the complex's melting temperature. It is concluded that a long wavelength shift of the fluorescence spectra occurs when the temperature is raised.

  8. Apratoxin H and Apratoxin A Sulfoxide from the Red Sea Cyanobacterium Moorea producens

    PubMed Central

    Thornburg, Christopher C.; Cowley, Elise S.; Sikorska, Justyna; Shaala, Lamiaa A.; Ishmael, Jane E.; Youssef, Diaa T.A.; McPhail, Kerry L.

    2014-01-01

    Cultivation of the marine cyanobacterium Moorea producens, collected from the Nabq Mangroves in the Gulf of Aqaba (Red Sea), led to the isolation of new apratoxin analogues, apratoxin H (1) and apratoxin A sulfoxide (2), together with the known apratoxins A-C, lyngbyabellin B and hectochlorin. The absolute configuration of these new potent cytotoxins was determined by chemical degradation, MS, NMR, and CD spectroscopy. Apratoxin H (1) contains pipecolic acid in place of the proline residue present in apratoxin A, expanding the known suite of naturally occurring analogues that display amino acid substitutions within the final module of the apratoxin biosynthetic pathway. The oxidation site of apratoxin A sulfoxide (2) was deduced from MS fragmentation patterns and IR data, and 2 could not be generated experimentally by oxidation of apratoxin A. The cytotoxicity of 1 and 2 to human NCI-H460 lung cancer cells (IC50 = 3.4 and 89.9 nM, respectively) provides further insight into the structure–activity relationships in the apratoxin series. Phylogenetic analysis of the apratoxin-producing cyanobacterial strains belonging to the genus Moorea, coupled with the recently annotated apratoxin biosynthetic pathway, supports the notion that apratoxin production and structural diversity may be specific to their geographical niche. PMID:24016099

  9. The Protein Oxidation Repair Enzyme Methionine Sulfoxide Reductase A Modulates Aβ Aggregation and Toxicity In Vivo

    PubMed Central

    Minniti, Alicia N.; Arrazola, Macarena S.; Bravo-Zehnder, Marcela; Ramos, Francisca; Inestrosa, Nibaldo C.

    2015-01-01

    Abstract Aims: To examine the role of the enzyme methionine sulfoxide reductase A-1 (MSRA-1) in amyloid-β peptide (Aβ)-peptide aggregation and toxicity in vivo, using a Caenorhabditis elegans model of the human amyloidogenic disease inclusion body myositis. Results: MSRA-1 specifically reduces oxidized methionines in proteins. Therefore, a deletion of the msra-1 gene was introduced into transgenic C. elegans worms that express the Aβ-peptide in muscle cells to prevent the reduction of oxidized methionines in proteins. In a constitutive transgenic Aβ strain that lacks MSRA-1, the number of amyloid aggregates decreases while the number of oligomeric Aβ species increases. These results correlate with enhanced synaptic dysfunction and mislocalization of the nicotinic acetylcholine receptor ACR-16 at the neuromuscular junction (NMJ). Innovation: This approach aims at modulating the oxidation of Aβ in vivo indirectly by dismantling the methionine sulfoxide repair system. The evidence presented here shows that the absence of MSRA-1 influences Aβ aggregation and aggravates locomotor behavior and NMJ dysfunction. The results suggest that therapies which boost the activity of the Msr system could have a beneficial effect in managing amyloidogenic pathologies. Conclusion: The absence of MSRA-1 modulates Aβ-peptide aggregation and increments its deleterious effects in vivo. Antioxid. Redox Signal. 22, 48–62. PMID:24988428

  10. Hepatic overexpression of methionine sulfoxide reductase A reduces atherosclerosis in apolipoprotein E-deficient mice.

    PubMed

    Xu, Yan-Yong; Du, Fen; Meng, Bing; Xie, Guang-Hui; Cao, Jia; Fan, Daping; Yu, Hong

    2015-10-01

    Methionine sulfoxide reductase A (MsrA), a specific enzyme that converts methionine-S-sulfoxide to methionine, plays an important role in the regulation of protein function and the maintenance of redox homeostasis. In this study, we examined the impact of hepatic MsrA overexpression on lipid metabolism and atherosclerosis in apoE-deficient (apoE(-/-)) mice. In vitro study showed that in HepG2 cells, lentivirus-mediated human MsrA (hMsrA) overexpression upregulated the expression levels of several key lipoprotein-metabolism-related genes such as liver X receptor α, scavenger receptor class B type I, and ABCA1. ApoE(-/-) mice were intravenously injected with lentivirus to achieve high-level hMsrA expression predominantly in the liver. We found that hepatic hMsrA expression significantly reduced plasma VLDL/LDL levels, improved plasma superoxide dismutase, and paraoxonase-1 activities, and decreased plasma serum amyloid A level in apoE(-/-) mice fed a Western diet, by significantly altering the expression of several genes in the liver involving cholesterol selective uptake, conversion and excretion into bile, TG biosynthesis, and inflammation. Moreover, overexpression of hMsrA resulted in reduced hepatic steatosis and aortic atherosclerosis. These results suggest that hepatic MsrA may be an effective therapeutic target for ameliorating dyslipidemia and reducing atherosclerosis-related cardiovascular diseases. PMID:26318157

  11. Characterisation, solubility and intrinsic dissolution behaviour of benzamide: dibenzyl sulfoxide cocrystal.

    PubMed

    Grossjohann, Christine; Eccles, Kevin S; Maguire, Anita R; Lawrence, Simon E; Tajber, Lidia; Corrigan, Owen I; Healy, Anne Marie

    2012-01-17

    This study examined the 1:1 cocrystal benzamide:dibenzyl sulfoxide, comprising the poorly water soluble dibenzyl sulfoxide (DBSO) and the more soluble benzamide (BA), to establish if this cocrystal shows advantages in terms of solubility and dissolution in comparison to its pure components and to a physical mixture. Solubility studies were performed by measuring DBSO solubility as a function of BA concentration, and a ternary phase diagram was constructed. Dissolution was examined through intrinsic dissolution studies. Solid-state characterisation was carried out by powder X-ray diffraction (PXRD), energy-dispersive X-ray diffraction (EDX), infra-red spectroscopy (ATR-FTIR) and thermal analysis. DBSO solubility was increased by means of complexation with BA. For the cocrystal, the solubility of both components was decreased in comparison to pure components. The cocrystal was identified as metastable and incongruently saturating. Dissolution studies revealed that dissolution of DBSO from the cocrystal was not enhanced in comparison to the pure compound or a physical mix, while BA release was retarded and followed square root of time kinetics. At the disk surface a layer of DBSO was found. The extent of complexation in solution can change the stability of the complex substantially. Incongruent solubility and dissolution behaviour of a cocrystal can result in no enhancement in the dissolution of the less soluble component and retardation of release of the more soluble component. PMID:22020274

  12. Dimethyl sulfoxide can initiate cell divisions of arrested callus protoplasts by promoting cortical microtuble assembly

    SciTech Connect

    Hahne, G.; Hoffmann, F.

    1984-09-01

    A serious problem in the technology of plant cell culture is that isolated protoplasts from many species are reluctant to divide. We have succeeded in inducing consecutive divisions in a naturally arrested system i.e., protoplasts from a hibiscus cell line, which do not divide under standard conditions and in an artificially arrested system i.e., colchicine-inhibited callus protoplasts of Nicotiana glutinosa, which do readily divide in the absence of colchicine. In both cases, the reinstallation of a net of cortical microtubules, which had been affected either by colchicine or by the protoplast isolation procedure, resulted in continuous divisions of the formerly arrested protoplasts. Several compounds known to support microtubule assembly in vitro were tested for their ability to promote microtubule assembly in vivo. Best results were obtained by addition of dimethyl sulfoxide to the culture medium. Unlimited amounts of callus could be produced with the dimethyl sulfoxide method from protoplasts which never developed a single callus in control experiments. 30 references, 3 figures.

  13. Echinococcus granulosus: membrane permeability of secondary hydatid cysts to albendazole sulfoxide.

    PubMed

    García-Llamazares, J L; Alvarez-de-Felipe, A I; Redondo-Cardeña, P A; Prieto-Fernández, J G

    1998-05-01

    The objectives of the present study were, first, to establish a methodology for evaluation of the permeability in vitro of hydatid cysts to different drugs and, second, to compare the permeability to albendazole sulfoxide of cysts from untreated animals, cysts from animals treated with 50 mg/kg netobimin for 5 days, and cysts from animals treated with 50 mg/kg netobimin plus 1.1 mg/kg fenbendazole for 5 days. The drug flow follows the Fick law, i.e., the uptake occurs by simple diffusion. We calculated the permeability constant of the cyst membrane by taking into account the disappearance velocity constant, the cyst area, and the incubation solution volume. The permeability value obtained for albendazole sulfoxide was 8.06+/-2.30 x 10(-6) cm s(-1) in cysts from untreated animals, 5.56+/-2.53 x l0(-6) cm s(-1) in cysts from animals treated with netobimin, and 7.05+/-3.04 x 10(-6) cm s(-1) in cysts from animals treated with netobimin +/- fenbendazole. These permeability values show significant differences (P < 0.05). PMID:9610641

  14. Structural Insights into Interaction between Mammalian Methionine Sulfoxide Reductase B1 and Thioredoxin

    PubMed Central

    Dobrovolska, Olena; Rychkov, Georgy; Shumilina, Elena; Nerinovski, Kirill; Schmidt, Alexander; Shabalin, Konstantin; Yakimov, Alexander; Dikiy, Alexander

    2012-01-01

    Maintenance of the cellular redox balance has vital importance for correcting organism functioning. Methionine sulfoxide reductases (Msrs) are among the key members of the cellular antioxidant defence system. To work properly, methionine sulfoxide reductases need to be reduced by their biological partner, thioredoxin (Trx). This process, according to the available kinetic data, represents the slowest step in the Msrs catalytic cycle. In the present paper, we investigated structural aspects of the intermolecular complex formation between mammalian MsrB1 and Trx. NMR spectroscopy and biocomputing were the two mostly used through the research approaches. The formation of NMR detectable MsrB1/Trx complex was monitored and studied in attempt to understand MsrB1 reduction mechanism. Using NMR data, molecular mechanics, protein docking, and molecular dynamics simulations, it was found that intermediate MsrB1/Trx complex is stabilized by interprotein β-layer. The complex formation accompanied by distortion of disulfide bond within MsrB1 facilitates the reduction of oxidized MsrB1 as it is evidenced by the obtained data. PMID:22505815

  15. Methionine sulfoxide reductase regulates brain catechol-O-methyl transferase activity.

    PubMed

    Moskovitz, Jackob; Walss-Bass, Consuelo; Cruz, Dianne A; Thompson, Peter M; Bortolato, Marco

    2014-10-01

    Catechol-O-methyl transferase (COMT) plays a key role in the degradation of brain dopamine (DA). Specifically, low COMT activity results in higher DA levels in the prefrontal cortex (PFC), thereby reducing the vulnerability for attentional and cognitive deficits in both psychotic and healthy individuals. COMT activity is markedly reduced by a non-synonymous single-nucleotide polymorphism (SNP) that generates a valine-to-methionine substitution on the residue 108/158, by means of as-yet incompletely understood post-translational mechanisms. One post-translational modification is methionine sulfoxide, which can be reduced by the methionine sulfoxide reductase (Msr) A and B enzymes. We used recombinant COMT proteins (Val/Met108) and mice (wild-type (WT) and MsrA knockout) to determine the effect of methionine oxidation on COMT activity and COMT interaction with Msr, through a combination of enzymatic activity and Western blot assays. Recombinant COMT activity is positively regulated by MsrA, especially under oxidative conditions, whereas brains of MsrA knockout mice exhibited lower COMT activity (as compared with their WT counterparts). These results suggest that COMT activity may be reduced by methionine oxidation, and point to Msr as a key molecular determinant for the modulation of COMT activity in the brain. The role of Msr in modulating cognitive functions in healthy individuals and schizophrenia patients is yet to be determined. PMID:24735585

  16. An enantioselective central-axial-central chiral element transfer process leading to a concise synthesis of (+)-sterpurene: Intramolecular Diels-Alder reactions of vinylallene sulfoxides

    SciTech Connect

    Gibbs, R.A.; Bartels, K.; Lee, R.W.K.; Okamura, W.H. )

    1989-05-10

    The intramolecular Diels-Alder (IMDA) reaction of vinylallene sulfoxide 19 as the diene component occurs in a rapid and stereoselective manner at room temperature to give tricyclic 20 in good yield. Sulfoxide 19 cyclizes {approximately} 140 times faster than the corresponding hydrocarbon 15a. It was also shown that gem-dimethyl substitution on the tether linking the vinylallene and vinyl group accelerates the rate of cyclization by only a factor of {approximately} 2.6. Treatment of enantiomerically enriched diene propargyl alcohol 6 with benzenesulfenyl chloride gave vinyallene sulfoxide 4 which cyclized in a highly enantio- and diastereoselective fashion to afford optically active tricyclic sulfoxide 5. Sulfoxide 5 was converted in two steps to the novel sesquiterpene fungal metabolite (+)-sterpurene, thus establishing its absolute configuration. By use of 2D NMR techniques, most of the proton and carbon signals in the {sup 1}H and {sup 13}C NMR spectra of sterpurene (8) and the precursor diene 33 were assigned.

  17. Increased Catalytic Efficiency Following Gene Fusion of Bifunctional Methionine Sulfoxide Reductase Enzymes from Shewanella oneidensis

    PubMed Central

    Chen, Baowei; Markillie, Lye Meng; Xiong, Yijia; Mayer, M. Uljana; Squier, Thomas C.

    2008-01-01

    Methionine sulfoxide reductase enzymes MsrA and MsrB have complementary stereospecificies that respectively reduce the S- and R-stereoisomers of methionine sulfoxide (MetSO), and together function as critical antioxidant enzymes. In some pathogenic and metal -reducing bacteria these genes are fused to form a bifunctional methionine sulfoxide reductase (i.e., MsrBA) enzyme. To investigate how gene fusion affects the substrate specificity and catalytic activities of Msr, we have cloned and expressed the MsrBA enzyme from Shewanella oneidensis, a metal-reducing bacterium and fish pathogen. For comparison, we also cloned and expressed the wild-type MsrA enzyme from Shewanella oneidensis and a genetically engineered MsrB protein. MsrBA is able to completely reduce (i.e., repair) MetSO in the calcium regulatory protein calmodulin (CaM); while only partial repair is observed using both MsrA and MsrB enzymes together at 25 °C. A restoration of the normal protein fold is observed coincident with the repair of MetSO in oxidized CaM by MsrBA, as monitored by the time-dependent increases in the anisotropy associated with the rigidly bound multiuse affinity probe 4′5′-bis(1,3,2-dithoarsolan-2yl)fluorescein (FlAsH). Underlying the efficient repair of MetSO in oxidized CaM is the coordinate activity of the two catalytic domains in the MsrBA fusion protein, which results in an order of magnitude rate enhancement in comparison to the individual MsrA or MsrB enzymes alone. The coordinate binding of both domains of MsrBA permits the full repair of all MetSO in CaMox. The common expression of Msr fusion proteins in bacterial pathogens is consistent with an important role for this enzyme activity in the maintenance of protein function necessary for bacterial survival under highly oxidizing conditions associated with pathogenesis or bioremediation. PMID:17997579

  18. Electrical conductivity of solutions of copper(II) nitrate crystalohydrate in dimethyl sulfoxide

    NASA Astrophysics Data System (ADS)

    Mamyrbekova, Aigul K.; Mamitova, A. D.; Mamyrbekova, Aizhan K.

    2016-06-01

    Conductometry is used to investigate the electric conductivity of Cu(NO3)2 ṡ 3H2O solutions in dimethyl sulfoxide in the 0.01-2.82 M range of concentrations and at temperatures of 288-318 K. The limiting molar conductivity of the electrolyte and the mobility of Cu2+ and NO 3 - ions, the effective coefficients of diffusion of copper(II) ions and nitrate ions, and the degree and constant of electrolytic dissociation are calculated for different temperatures from the experimental results. It is established that solutions containing 0.1-0.6 M copper nitrate trihydrate in DMSO having low viscosity and high electrical conductivity can be used in electrochemical deposition.

  19. Solvatomer dynamics of aluminium sulfate in dimethyl sulfoxide/water mixtures

    NASA Astrophysics Data System (ADS)

    Kaatze, U.; Telgmann, T.; Miecznik, P.

    1999-08-01

    The ultrasonic absorption spectra between about 200 kHz and 2 GHz have been measured for 0.1 mol l -1 solutions of Al 2(SO 4) 3 in several mixtures of dimethyl sulfoxide (DMSO) and water at 25°C. A suitable description of the spectra is obtained with a sum of two Debye-type spectral terms and a term reflecting correlated non-critical fluctuations in ion concentration. The outer-outer-sphere/outer-sphere ion complex equilibrium of the electrolyte seems to be reflected by the low-frequency Debye term, the formation/dissociation of outer-outer-sphere complexes by the concentration fluctuation term. DMSO exchange from solvatomers appears to be the mechanism behind the high-frequency Debye term.

  20. Lack of effect of deferoxamine, dimethyl sulfoxide, and catalase on monocrotaline pyrrole pulmonary injury

    SciTech Connect

    Bruner, L.H.; Johnson, K.; Carpenter, L.J.; Roth, R.A.

    1987-01-01

    Monocrotaline pyrrole (MCTP) is a reactive metabolite of the pyrrolizidine alkaloid monocrotaline. MCTP given intravenously to rats causes pulmonary hypertension and right ventricular hypertrophy. Lesions in lungs after MCTP treatment contain macrophages and neutrophils, which may contribute to the damage by generation of reactive oxygen metabolites. Rats were treated with MCTP and agents known to protect against oxygen radical-mediated damage in acute models of neutrophil-dependent lung injury. Rats received MCTP and deferoxamine mesylate (DF), dimethyl sulfoxide (DMSO), or polyethylene glycol-coupled catalase (PEG-CAT). MCTP/vehicle-treated controls developed lung injury manifested as increased lung weight, release of lactate dehydrogenase into the airway, and sequestration of SVI-labeled bovine serum albumin in the lungs. Cotreatment of rats with DF, DMSO, or PEG-CAT did not protect against the injury due to MCTP. These results suggest that toxic oxygen metabolites do not play an important role in the pathogenesis of MCTP-induced pulmonary injury.

  1. Syntheses and Antituberculosis Activity of 1,3-Benzothiazinone Sulfoxide and Sulfone Derived from BTZ043

    PubMed Central

    2014-01-01

    The discovery of 1,3-benzothiazin-4-ones (BTZs), especially BTZ043 and PBTZ-169 as potent agents for the treatment of tuberculosis, prompted intensive research related to development of potential antituberculosis agents based on electron deficient nitroaromatic scaffolds. Herein we report the syntheses, computational and NMR studies and anti-TB activity of oxidation products, 1,3-benzothiazinone sulfoxide (BTZ-SO) and 1,3-benzothiazinone sulfone (BTZ-SO2) derived from BTZ043. The combined computational and NMR work revealed differences in the total charge densities and molecular shapes of the oxidation products. While docking studies still suggested similar interactions and binding patterns for both products with the target DprE1 enzyme, antituberculosis assays indicated remarkable differences in their activity. Interestingly, BTZ-SO possesses potent activity against nonpathogenic and pathogenic mycobacterial strains, but BTZ-SO2 is only weakly active. PMID:25699139

  2. Thermal characterization of ZnO-DMSO (dimethyl sulfoxide) colloidal dispersions using the inverse photopyroelectric technique.

    PubMed

    Marín, E; Calderón, A; Díaz, D

    2009-05-01

    Nanofluids, i.e., colloidal dispersions of nanoparticles in a base liquid (solvent), have received considerable attention in the last years due to their potential applications. One attractive feature of these systems is that their thermal conductivity can exceed the corresponding values of the base fluid and of the fluid with large particles of the same chemical composition. However, there is a lack of agreement between published results and the suggested mechanisms which explain the thermal conductivity enhancement. Here we show the possibilities of the inverse photopyroelectric method for the determination of the effective thermal effusivity of the system constituted by small ZnO nanoparticles dispersed in dimethyl sulfoxide, as a function of the nanoparticles volumetric fraction. Using a phenomenological model we estimated the thermal conductivity of these colloidal samples without observing any significant enhancement of this parameter above effective medium predictions. PMID:19430157

  3. Syntheses and Antituberculosis Activity of 1,3-Benzothiazinone Sulfoxide and Sulfone Derived from BTZ043.

    PubMed

    Tiwari, Rohit; Miller, Patricia A; Cho, Sanghyun; Franzblau, Scott G; Miller, Marvin J

    2015-02-12

    The discovery of 1,3-benzothiazin-4-ones (BTZs), especially BTZ043 and PBTZ-169 as potent agents for the treatment of tuberculosis, prompted intensive research related to development of potential antituberculosis agents based on electron deficient nitroaromatic scaffolds. Herein we report the syntheses, computational and NMR studies and anti-TB activity of oxidation products, 1,3-benzothiazinone sulfoxide (BTZ-SO) and 1,3-benzothiazinone sulfone (BTZ-SO2) derived from BTZ043. The combined computational and NMR work revealed differences in the total charge densities and molecular shapes of the oxidation products. While docking studies still suggested similar interactions and binding patterns for both products with the target DprE1 enzyme, antituberculosis assays indicated remarkable differences in their activity. Interestingly, BTZ-SO possesses potent activity against nonpathogenic and pathogenic mycobacterial strains, but BTZ-SO2 is only weakly active. PMID:25699139

  4. Dual inhibitory effects of dimethyl sulfoxide on poly(ADP-ribose) synthetase.

    PubMed

    Banasik, M; Ueda, K

    1999-01-01

    Dimethyl sulfoxide (DMSO), a solvent popularly used for dissolving water-insoluble compounds, is a weak inhibitor of poly(ADP-ribose) synthetase, that is a nuclear enzyme producing (ADP-ribose)n from NAD+. The inhibitory mode and potency depend on the concentration of substrate, NAD+, as well as the temperature of the reaction; at micromolar concentrations of NAD+, the inhibition by DMSO is biphasic at 37 degrees C, but is monophasic and apparently competitive with NAD+ at 25 degrees C. DMSO, on the other hand, diminishes dose-dependently and markedly the inhibitory potency of benzamide and other inhibitors. Other organic solvents, ethanol and methanol, also show a biphasic effect on the synthetase activity at different concentrations. PMID:10445046

  5. Dimethyl Sulfoxide Enhances Effectiveness of Skin Antiseptics and Reduces Contamination Rates of Blood Cultures

    PubMed Central

    LaSala, Paul R.; Han, Xiang-Yang; Rolston, Kenneth V.; Kontoyiannis, Dimitrios P.

    2012-01-01

    Effective skin antisepsis is of central importance in the prevention of wound infections, colonization of medical devices, and nosocomial transmission of microorganisms. Current antiseptics have a suboptimal efficacy resulting in substantial infectious morbidity, mortality, and increased health care costs. Here, we introduce an in vitro method for antiseptic testing and a novel alcohol-based antiseptic containing 4 to 5% of the polar aprotic solvent dimethyl sulfoxide (DMSO). The DMSO-containing antiseptic resulted in a 1- to 2-log enhanced killing of Staphylococcus epidermidis and other microbes in vitro compared to the same antiseptic without DMSO. In a prospective clinical validation, blood culture contamination rates were reduced from 3.04% for 70% isopropanol–1% iodine (control antiseptic) to 1.04% for 70% isopropanol–1% iodine–5% DMSO (P < 0.01). Our results predict that improved skin antisepsis is possible using new formulations of antiseptics containing strongly polarized but nonionizing (polar aprotic) solvents. PMID:22378911

  6. The extraction of water, nitric acid, and uranyl nitrate by di-2-ethylhexyl sulfoxide in dodecane

    SciTech Connect

    Moyer, B.A.; Baes, C.F. Jr.; McDowell, W.J.; Caley, C.E.; Case, G.N. )

    1989-01-01

    The extraction of water, nitric acid, and uranyl nitrate by di-2-ethylhexyl sulfoxide (DEHSO) in dodecane has been measured. Using the program SXLSQA, the data were modeled with correction for nonideality effects (treatments of Hildebrand and Scott and of Pitzer) in terms of the organic-phase species (DEHSO)(H{sub 2}O), (DEHSO){sub 2}(H{sub 2}O), (DEHSO)(HNO{sub 3}), (DEHSO){sub 2}(HNO{sub 3})(H{sub 2}O), (DEHSO)(HNO{sub 3}){sub 2}(H{sub 2}O), and UO{sub 2}(NO{sub 3}){sub 2}(DEHSO){sub 2}(H{sub 2}O){sub w}. 11 refs., 4 figs.

  7. [Fluorescence enhancement character of terbium perchlorate and thulium perchlorate with phenylcarboxymethyl sulfoxide coordination compounds].

    PubMed

    Li, Wen-xian; Wu, Guo-jiun; Liu, Zhong-shi; Han, Feng-mei

    2002-12-01

    (Tb1-x Tmx).L2.(ClO4).2H2O(x = 0.000 to 0.200, L = C6H5SOCH2COO-) have been synthesized. The coordination compounds have been studied by means of composition analysis, molar conductivity, IR, and the condition of coordination have been inferred. In the fluorescent spectra it was found that Tm3+ has a strongly sensitization effect to the fluorescence of Tb3+. The fluorescent emission intensity of Terbium perchlorate with phenylcarboxymethyl sulfoxide coordination compounds would be enhanced by Tm3+ in mixing. Tm3+ has a sensitization to the fluorescence of Tb3+ in the ratio of Tb3+:Tm3+ = 0.999:0.001-0.900:0.100. In the solubility experiment it was found that the complexes have high solubility in ethanol. PMID:12914160

  8. Preferential solvation of lysozyme in dimethyl sulfoxide/water binary mixture probed by terahertz spectroscopy.

    PubMed

    Das, Dipak Kumar; Patra, Animesh; Mitra, Rajib Kumar

    2016-09-01

    We report the changes in the hydration dynamics around a model protein hen egg white lysozyme (HEWL) in water-dimethyl sulfoxide (DMSO) binary mixture using THz time domain spectroscopy (TTDS) technique. DMSO molecules get preferentially solvated at the protein surface, as indicated by circular dichroism (CD) and Fourier transform infrared (FTIR) study in the mid-infrared region, resulting in a conformational change in the protein, which consequently modifies the associated hydration dynamics. As a control we also study the collective hydration dynamics of water-DMSO binary mixture and it is found that it follows a non-ideal behavior owing to the formation of DMSO-water clusters. It is observed that the cooperative dynamics of water at the protein surface does follow the DMSO-mediated conformational modulation of the protein. PMID:27372901

  9. Onychomycosis treated with a dilute povidone–iodine/dimethyl sulfoxide preparation

    PubMed Central

    Capriotti, Kara; Capriotti, Joseph A

    2015-01-01

    Background Povidone–iodine (PVP-I) 10% aqueous solution is a well-known, nontoxic, commonly used topical antiseptic with no reported incidence of fungal resistance. We have been using a low-dose formulation of 1% PVP-I (w/w) in a solution containing dimethyl sulfoxide (DMSO) in our clinical practice for a variety of indications. Presented here is our clinical experience with this novel formulation in a severe case of onychomycosis that was resistant to any other treatment. Findings A 49-year-old woman who had been suffering from severe onychomycosis for years presented after failing to find any remedy including over the counter (OTC), topical, and systemic oral prescribed therapies. Conclusion The topical povidone–iodine/DMSO system was very effective in this case at alleviating the signs and symptoms of onychomycosis. This novel combination warrants further investigation in randomized, controlled trials to further elucidate its clinical utility. PMID:26491374

  10. A sulfonium cation intermediate in the mechanism of methionine sulfoxide reductase B: a DFT study.

    PubMed

    Robinet, Jesse J; Dokainish, Hisham M; Paterson, David J; Gauld, James W

    2011-07-28

    The hybrid density functional theory method B3LYP in combination with three systematically larger active site models has been used to investigate the substrate binding and catalytic mechanism by which Neisseria gonorrhoeae methionine sulfoxide reductase B (MsrB) reduces methionine-R-sulfoxide (Met-R-SO) to methionine. The first step in the overall mechanism is nucleophilic attack of an active site thiolate at the sulfur of Met-R-SO to form an enzyme-substrate sulfurane. This occurs with concomitant proton transfer from an active site histidine (His480) residue to the substrates oxygen center. The barrier for this step, calculated using our largest most complete active site model, is 17.2 kJ mol(-1). A subsequent conformational rearrangement and intramolecular -OH transfer to form an enzyme-derived sulfenic acid ((Cys495)S-OH) is not enzymatically feasible. Instead, transfer of a second proton from a second histidyl active site residue (His477) to the sulfurane's oxygen center to give water and a sulfonium cation intermediate is found to be greatly preferred, occurring with a quite low barrier of just 1.2 kJ mol(-1). Formation of the final product complex in which an intraprotein disulfide bond is formed with generation of methionine preferably occurs in one step via nucleophilic attack of the sulfur of a second enzyme thiolate ((Cys440)S(-)) at the S(Cys495) center of the sulfonium intermediate with a barrier of 23.8 kJ mol(-1). An alternate pathway for formation of the products via a sulfenic acid intermediate involves enzymatically feasible, but higher energy barriers. The role and impact of hydrogen bonding and active site residues on the properties and stability of substrate and mechanism intermediates and the affects of mutating His477 are also examined and discussed. PMID:21721538

  11. Regeneration Mechanisms of Arabidopsis thaliana Methionine Sulfoxide Reductases B by Glutaredoxins and Thioredoxins*

    PubMed Central

    Tarrago, Lionel; Laugier, Edith; Zaffagnini, Mirko; Marchand, Christophe; Le Maréchal, Pierre; Rouhier, Nicolas; Lemaire, Stéphane D.; Rey, Pascal

    2009-01-01

    Methionine oxidation leads to the formation of S- and R-diastereomers of methionine sulfoxide (MetSO), which are reduced back to methionine by methionine sulfoxide reductases (MSRs) A and B, respectively. MSRBs are classified in two groups depending on the conservation of one or two redox-active Cys; 2-Cys MSRBs possess a catalytic Cys-reducing MetSO and a resolving Cys, allowing regeneration by thioredoxins. The second type, 1-Cys MSRBs, possess only the catalytic Cys. The biochemical mechanisms involved in activity regeneration of 1-Cys MSRBs remain largely elusive. In the present work we used recombinant plastidial Arabidopsis thaliana MSRB1 and MSRB2 as models for 1-Cys and 2-Cys MSRBs, respectively, to delineate the Trx- and glutaredoxin-dependent reduction mechanisms. Activity assays carried out using a series of cysteine mutants and various reductants combined with measurements of free thiols under distinct oxidation conditions and mass spectrometry experiments show that the 2-Cys MSRB2 is reduced by Trx through a dithiol-disulfide exchange involving both redox-active Cys of the two partners. Regarding 1-Cys MSRB1, oxidation of the enzyme after substrate reduction leads to the formation of a stable sulfenic acid on the catalytic Cys, which is subsequently glutathionylated. The deglutathionylation of MSRB1 is achieved by both mono- and dithiol glutaredoxins and involves only their N-terminal conserved catalytic Cys. This study proposes a detailed mechanism of the regeneration of 1-Cys MSRB activity by glutaredoxins, which likely constitute physiological reductants for this type of MSR. PMID:19457862

  12. Methionine Sulfoxide Reductases Preferentially Reduce Unfolded Oxidized Proteins and Protect Cells from Oxidative Protein Unfolding*

    PubMed Central

    Tarrago, Lionel; Kaya, Alaattin; Weerapana, Eranthie; Marino, Stefano M.; Gladyshev, Vadim N.

    2012-01-01

    Reduction of methionine sulfoxide (MetO) residues in proteins is catalyzed by methionine sulfoxide reductases A (MSRA) and B (MSRB), which act in a stereospecific manner. Catalytic properties of these enzymes were previously established mostly using low molecular weight MetO-containing compounds, whereas little is known about the catalysis of MetO reduction in proteins, the physiological substrates of MSRA and MSRB. In this work we exploited an NADPH-dependent thioredoxin system and determined the kinetic parameters of yeast MSRA and MSRB using three different MetO-containing proteins. Both enzymes showed Michaelis-Menten kinetics with the Km lower for protein than for small MetO-containing substrates. MSRA reduced both oxidized proteins and low molecular weight MetO-containing compounds with similar catalytic efficiencies, whereas MSRB was specialized for the reduction of MetO in proteins. Using oxidized glutathione S-transferase as a model substrate, we showed that both MSR types were more efficient in reducing MetO in unfolded than in folded proteins and that their activities increased with the unfolding state. Biochemical quantification and identification of MetO reduced in the substrates by mass spectrometry revealed that the increased activity was due to better access to oxidized MetO in unfolded proteins; it also showed that MSRA was intrinsically more active with unfolded proteins regardless of MetO availability. Moreover, MSRs most efficiently protected cells from oxidative stress that was accompanied by protein unfolding. Overall, this study indicates that MSRs serve a critical function in the folding process by repairing oxidatively damaged nascent polypeptides and unfolded proteins. PMID:22628550

  13. Antibacterial action of combinations of oxytetracycline, dimethyl sulfoxide, and EDTA-tromethamine on Proteus, Salmonella, and Aeromonas.

    PubMed

    Wooley, R E; Gilbert, J P; Shotts, E B

    1982-01-01

    Antibacterial effects against Proteus mirabilis, Salmonella typhimurium, and Aeromonas hydrophila were obtained with subminimal inhibitory concentrations of oxytetracycline and EDTA-tromethamine. Antibacterial effects were not observed with subminimal inhibitory concentrations of dimethyl sulfoxide plus oxytetracycline or with dimethyl sulfoxide plus EDTA-tromethamine. Using a 2-dimensional Microtiter checkerboard technique, inhibitory activities of the various combinations of solutions were studied, and isobolograms were plotted. A synergistic effect was seen with combinations of oxytetracycline and EDTA-tromethamine. The greatest synergistic effect was observed when the mixture was caused to react with P mirabilis. These findings were confirmed by kinetic studies of microbial death, using one-fourth minimal inhibitory concentrations of these preparations. PMID:6807142

  14. Iodine-Catalyzed Cross Dehydrogenative Coupling Reaction: A Regioselective Sulfenylation of Imidazoheterocycles Using Dimethyl Sulfoxide as an Oxidant.

    PubMed

    Siddaraju, Yogesh; Prabhu, Kandikere Ramaiah

    2016-09-01

    A regioselective formation of C-S bonds has been achieved using a cross dehydrogenative coupling (CDC) protocol using iodine as a catalyst and dimethyl sulfoxide as an oxidant under green chemistry conditions. This strategy employs the reaction of easily available heterocyclic thiols or thiones with imidazoheterocycles. This protocol provides an efficient, mild, and inexpensive method for sulfenylation of imidazoheterocycles with a diverse range of heterocyclic thiols and heterocyclic thiones. PMID:27490357

  15. Enantioselective Allylic C-H Oxidation of Terminal Olefins to Isochromans by Palladium(II)/Chiral Sulfoxide Catalysis.

    PubMed

    Ammann, Stephen E; Liu, Wei; White, M Christina

    2016-08-01

    The enantioselective synthesis of isochroman motifs has been accomplished by palladium(II)-catalyzed allylic C-H oxidation from terminal olefin precursors. Critical to the success of this goal was the development and utilization of a novel chiral aryl sulfoxide-oxazoline (ArSOX) ligand. The allylic C-H oxidation reaction proceeds with the broadest scope and highest levels of asymmetric induction reported to date (avg. 92 % ee, 13 examples with greater than 90 % ee). PMID:27376625

  16. Charge-transfer complexation and photoreduction of viologen derivatives bearing the para-substituted benzophenone group in dimethyl sulfoxide

    SciTech Connect

    Tanaka, Chiho; Nambu, Yoko; Endo, Takeshi

    1992-08-20

    New viologen derivatives having the various para-substituted benzophenone groups connected with a -(CH{sub 2}){sub 3}-linkage were effectively photoreduced by dimethyl sulfoxide by the intramolecular charge transfer complex formation between the viologen and benzophenone groups through effective stacking. The photoreduction was enhanced by the introduction of electron-donating para-substituents on the benzophenone units which were favorable for the intramolecular charge transfer complexation. 6 refs., 5 figs.

  17. Cloning the expression of a mammalian gene involved in the reduction of methionine sulfoxide residues in proteins.

    PubMed Central

    Moskovitz, J; Weissbach, H; Brot, N

    1996-01-01

    An enzyme that reduces methionine sulfoxide [Met(O)] residues in proteins [peptide Met(O) reductase (MsrA), EC 1.8.4.6; originally identified in Escherichia coli] was purified from bovine liver, and the cDNA encoding this enzyme was cloned and sequenced. The mammalian homologue of E. coli msrA (also called pmsR) cDNA encodes a protein of 255 amino acids with a calculated molecular mass of 25,846 Da. This protein has 61% identity with the E. coli MsrA throughout a region encompassing a 199-amino acid overlap. The protein has been overexpressed in E. coli and purified to homogeneity. The mammalian recombinant MsrA can use as substrate, proteins containing Met(O) as well as other organic compounds that contain an alkyl sulfoxide group such as N-acetylMet(O), Met(O), and dimethyl sulfoxide. Northern analysis of rat tissue extracts showed that rat msrA mRNA is present in a variety of organs with the highest level found in kidney. This is consistent with the observation that kidney extracts also contained the highest level of enzyme activity. Images Fig. 3 Fig. 5 PMID:8700890

  18. Methionine sulfoxide profiling of milk proteins to assess the influence of lipids on protein oxidation in milk.

    PubMed

    Wüst, Johannes; Pischetsrieder, Monika

    2016-06-15

    Thermal treatment of milk and milk products leads to protein oxidation, mainly the formation of methionine sulfoxide. Reactive oxygen species, responsible for the oxidation, can be generated by Maillard reaction, autoxidation of sugars, or lipid peroxidation. The present study investigated the influence of milk fat on methionine oxidation in milk. For this purpose, quantitative methionine sulfoxide profiling of all ten methionine residues of β-lactoglobulin, α-lactalbumin, and αs1-casein was carried out by ultrahigh-performance liquid chromatography-electrospray ionization tandem mass spectrometry with scheduled multiple reaction monitoring (UHPLC-ESI-MS/MS-sMRM). Analysis of defatted and regular raw milk samples after heating for up to 8 min at 120 °C and analysis of ultrahigh-temperature milk samples with 0.1%, 1.5%, and 3.5% fat revealed that methionine oxidation of the five residues of the whey proteins and of residues M 123, M 135, and M 196 of αs1-casein was not affected or even suppressed in the presence of milk fat. Only the oxidation of residues M 54 and M 60 of αs1-casein was promoted by lipids. In evaporated milk samples, formation of methionine sulfoxide was hardly influenced by the fat content of the samples. Thus, it can be concluded that lipid oxidation products are not the major cause of methionine oxidation in milk. PMID:26927981

  19. Determination of methiocarb and its degradation products, methiocarb sulfoxide and methiocarb sulfone, in bananas using QuEChERS extraction.

    PubMed

    Plácido, Alexandra; Paíga, Paula; Lopes, David H; Correia, Manuela; Delerue-Matos, Cristina

    2013-01-16

    The present work describes the development of an analytical method for the determination of methiocarb and its degradation products (methiocarb sulfoxide and methiocarb sulfone) in banana samples, using the QuEChERS (quick, easy, cheap, effective, rugged, and safe) procedure followed by liquid chromatography coupled to photodiode array detector (LC-PAD). Calibration curves were linear in the range of 0.5-10 mg L⁻¹ for all compounds studied. The average recoveries, measured at 0.1 mg kg⁻¹ wet weight, were 92.0 (RSD = 1.8%, n = 3), 84.0 (RSD = 3.9%, n = 3), and 95.2% (RSD = 1.9%, n = 3) for methiocarb sulfoxide, methiocarb sulfone, and methiocarb, respectively. Banana samples treated with methiocarb were collected from an experimental field. The developed method was applied to the analysis of 24 samples (peel and pulp) and to 5 banana pulp samples. Generally, the highest levels were found for methiocarb sulfoxide and methiocarb. Methiocarb sulfone levels were below the limit of quantification, except in one sample (not detected). PMID:23252625

  20. Dimethyl sulfoxide at high concentrations inhibits non-selective cation channels in human erythrocytes.

    PubMed

    Nardid, Oleg A; Schetinskey, Miroslav I; Kucherenko, Yuliya V

    2013-03-01

    Dimethyl sulfoxide (DMSO), a by-product of the pulping industry, is widely used in biological research, cryobiology and medicine. On cellular level DMSO was shown to suppress NMDA-AMPA channels activation, blocks Na+ channel activation and attenuates Ca2+ influx (Lu and Mattson 2001). In the present study we explored the whole-cell patch-clamp to examine the acute effect of high concentrations of DMSO (0.1-2 mol/l) on cation channels activity in human erythrocytes. Acute application of DMSO (0.1-2 mol/l) dissolved in Cl--containing saline buffer solution significantly inhibited cation conductance in human erythrocytes. Inhibition was concentration-dependent and had an exponential decay profile. DMSO (2 mol/l) induced cation inhibition in Cl-- containing saline solutions of: 40.3 ± 3.9% for K+, 35.4 ± 3.1% for Ca2+ and 47.4 ± 1.9% for NMDG+. Substitution of Cl- with gluconate- increased the inhibitory effect of DMSO on the Na+ current. Inhibitory effect of DMSO was neither due to high permeability of erythrocytes to DMSO nor to an increased tonicity of the bath media since no effect was observed in 2 mol/l glycerol solution. In conclusion, we have shown that high concentrations of DMSO inhibit the non-selective cation channels in human erythrocytes and thus protect the cells against Na+ and Ca2+ overload. Possible mechanisms of DMSO effect on cation conductance are discussed. PMID:23531832

  1. Multinuclear NMR spectroscopy for differentiation of molecular configurations and solvent properties between acetone and dimethyl sulfoxide

    NASA Astrophysics Data System (ADS)

    Wen, Yuan-Chun; Kuo, Hsiao-Ching; Jia, Hsi-Wei

    2016-04-01

    The differences in molecular configuration and solvent properties between acetone and dimethyl sulfoxide (DMSO) were investigated using the developed technique of 1H, 13C, 17O, and 1H self-diffusion liquid state nuclear magnetic resonance (NMR) spectroscopy. Acetone and DMSO samples in the forms of pure solution, ionic salt-added solution were used to deduce their active sites, relative dipole moments, dielectric constants, and charge separations. The NMR results suggest that acetone is a trigonal planar molecule with a polarized carbonyl double bond, whereas DMSO is a trigonal pyramidal-like molecule with a highly polarized S-O single bond. Both molecules use their oxygen atoms as the active sites to interact other molecules. These different molecular models explain the differences their physical and chemical properties between the two molecules and explain why DMSO is classified as an aprotic but highly dipolar solvent. The results are also in agreement with data obtained using X-ray diffraction, neutron diffraction, and theoretical calculations.

  2. Methionine Sulfoxide Reductases Protect against Oxidative Stress in Staphylococcus aureus Encountering Exogenous Oxidants and Human Neutrophils

    PubMed Central

    Pang, Yun Yun; Schwartz, Jamie; Bloomberg, Sarah; Boyd, Jeffrey M; Horswill, Alexander R.; Nauseef, William M.

    2013-01-01

    To establish infection successfully, S. aureus must evade clearance by polymorphonuclear neutrophils (PMN). We studied the expression and regulation of the methionine sulfoxide reductases (Msr) that are involved in the repair of oxidized staphylococcal proteins and investigated their influence over the fate of S. aureus exposed to oxidants or PMN. We evaluated a mutant deficient in msrA1 and msrB for susceptibility to hydrogen peroxide, hypochlorous acid and PMN. The expression of msrA1 in wild-type bacteria ingested by human PMN was assessed by real-time PCR. The regulation of msr was studied by screening a library of two-component regulatory system (TCS) mutants for altered msr responses. Relative to the wild-type, bacteria deficient in Msr were more susceptible to oxidants and to PMN. Upregulation of staphylococcal msrA1 occurred within the phagosomes of normal PMN and PMN deficient in NADPH oxidase activity. Furthermore, PMN granule-rich extract stimulated the upregulation of msrA1. Modulation of msrA1 within PMN was shown to be partly dependent on the VraSR TCS. Msr contributes to staphylococcal responses to oxidative attack and PMN. Our study highlights a novel interaction between the oxidative protein repair pathway and the VraSR TCS that is involved in cell wall homeostasis. PMID:24247266

  3. Methionine sulfoxide reductase: chemistry, substrate binding, recycling process and oxidase activity.

    PubMed

    Boschi-Muller, Sandrine; Branlant, Guy

    2014-12-01

    Three classes of methionine sulfoxide reductases are known: MsrA and MsrB which are implicated stereo-selectively in the repair of protein oxidized on their methionine residues; and fRMsr, discovered more recently, which binds and reduces selectively free L-Met-R-O. It is now well established that the chemical mechanism of the reductase step passes through formation of a sulfenic acid intermediate. The oxidized catalytic cysteine can then be recycled by either Trx when a recycling cysteine is operative or a reductant like glutathione in the absence of recycling cysteine which is the case for 30% of the MsrBs. Recently, it was shown that a subclass of MsrAs with two recycling cysteines displays an oxidase activity. This reverse activity needs the accumulation of the sulfenic acid intermediate. The present review focuses on recent insights into the catalytic mechanism of action of the Msrs based on kinetic studies, theoretical chemistry investigations and new structural data. Major attention is placed on how the sulfenic acid intermediate can be formed and the oxidized catalytic cysteine returns back to its reduced form. PMID:25108804

  4. Synthesis of ZnO nanoparticles on a clay mineral surface in dimethyl sulfoxide medium.

    PubMed

    Németh, József; Rodríguez-Gattorno, Geonel; Díaz, David; Vázquez-Olmos, América R; Dékány, Imre

    2004-03-30

    Nanocrystalline ZnO particles have been prepared with different methods using zinc cyclohexanebutyrate as precursor in dimethyl sulfoxide (DMSO) medium via alkaline hydrolysis. A series of preparations were carried out in the presence of layered silicates (kaolinite and montmorillonite). It was revealed by different measurement techniques that the presence of the clay minerals has a stabilization influence on the size of the ZnO nanocrystals. UV-vis absorption spectra show a blue shift when the nanoparticles are prepared in the presence of the clay minerals. The average particle diameters calculated from the Brus equation ranged from 2.6 to 13.0 nm. The UV-vis spectra of the synthesized nanoparticles did not show any red shift after 2-3 days, demonstrating that stable ZnO nanocrystals are present in the dispersions. The presence of the ZnO nanoparticles was also proven by fluorescence measurements. A number of the nanoparticles are incorporated into the interlamellar space of the clays, and an intercalated structure is formed as proven by X-ray diffraction (XRD) measurements. The size of the nanoparticles in the interlamellar space is in the range of 1-2 nm according to the XRD patterns. Transmission electron microscopy and high-resolution transmission electron microscopy investigations were applied to determine directly the particle size and the size distribution of the nanoparticles. PMID:15835163

  5. Solvation structure and transport properties of alkali cations in dimethyl sulfoxide under exogenous static electric fields

    SciTech Connect

    Kerisit, Sebastien; Vijayakumar, M. E-mail: karl.mueller@pnnl.gov; Han, Kee Sung; Mueller, Karl T. E-mail: karl.mueller@pnnl.gov

    2015-06-14

    A combination of molecular dynamics simulations and pulsed field gradient nuclear magnetic resonance spectroscopy is used to investigate the role of exogenous electric fields on the solvation structure and dynamics of alkali ions in dimethyl sulfoxide (DMSO) and as a function of temperature. Good agreement was obtained, for select alkali ions in the absence of an electric field, between calculated and experimentally determined diffusion coefficients normalized to that of pure DMSO. Our results indicate that temperatures of up to 400 K and external electric fields of up to 1 V nm{sup −1} have minimal effects on the solvation structure of the smaller alkali cations (Li{sup +} and Na{sup +}) due to their relatively strong ion-solvent interactions, whereas the solvation structures of the larger alkali cations (K{sup +}, Rb{sup +}, and Cs{sup +}) are significantly affected. In addition, although the DMSO exchange dynamics in the first solvation shell differ markedly for the two groups, the drift velocities and mobilities are not significantly affected by the nature of the alkali ion. Overall, although exogenous electric fields induce a drift displacement, their presence does not significantly affect the random diffusive displacement of the alkali ions in DMSO. System temperature is found to have generally a stronger influence on dynamical properties, such as the DMSO exchange dynamics and the ion mobilities, than the presence of electric fields.

  6. Arabidopsis Peptide Methionine Sulfoxide Reductase2 Prevents Cellular Oxidative Damage in Long NightsW⃞

    PubMed Central

    Bechtold, Ulrike; Murphy, Denis J.; Mullineaux, Philip M.

    2004-01-01

    Peptide methionine sulfoxide reductase (PMSR) is a ubiquitous enzyme that repairs oxidatively damaged proteins. In Arabidopsis (Arabidopsis thaliana), a null mutation in PMSR2 (pmsr2-1), encoding a cytosolic isoform of the enzyme, exhibited reduced growth in short-day conditions. In wild-type plants, a diurnally regulated peak of total PMSR activity occurred at the end of the 16-h dark period that was absent in pmsr2-1 plants. This PMSR activity peak in the wild-type plant coincided with increased oxidative stress late in the dark period in the mutant. In pmsr2-1, the inability to repair proteins resulted in higher levels of their turnover, which in turn placed an increased burden on cellular metabolism. This caused increased respiration rates, leading to the observed higher levels of oxidative stress. In wild-type plants, the repair of damaged proteins by PMSR2 at the end of the night in a short-day diurnal cycle alleviates this potential burden on metabolism. Although PMSR2 is not absolutely required for viability of plants, the observation of increased damage to proteins in these long nights suggests the timing of expression of PMSR2 is an important adaptation for conservation of their resources. PMID:15031406

  7. Solvent stimulated actuation of polyurethane-based shape memory polymer foams using dimethyl sulfoxide and ethanol

    NASA Astrophysics Data System (ADS)

    Boyle, A. J.; Weems, A. C.; Hasan, S. M.; Nash, L. D.; Monroe, M. B. B.; Maitland, D. J.

    2016-07-01

    Solvent exposure has been investigated to trigger actuation of shape memory polymers (SMPs) as an alternative to direct heating. This study aimed to investigate the feasibility of using dimethyl sulfoxide (DMSO) and ethanol (EtOH) to stimulate polyurethane-based SMP foam actuation and the required solvent concentrations in water for rapid actuation of hydrophobic SMP foams. SMP foams exhibited decreased T g when submerged in DMSO and EtOH when compared to water submersion. Kinetic DMA experiments showed minimal or no relaxation for all SMP foams in water within 30 min, while SMP foams submerged in EtOH exhibited rapid relaxation within 1 min of submersion. SMP foams expanded rapidly in high concentrations of DMSO and EtOH solutions, where complete recovery over 30 min was observed in DMSO concentrations greater than 90% and in EtOH concentrations greater than 20%. This study demonstrates that both DMSO and EtOH are effective at triggering volume recovery of polyurethane-based SMP foams, including in aqueous environments, and provides promise for use of this actuation technique in various applications.

  8. Dimethyl Sulfoxide Perturbs Cell Cycle Progression and Spindle Organization in Porcine Meiotic Oocytes

    PubMed Central

    Li, Xuan; Wang, Yan-Kui; Song, Zhi-Qiang; Du, Zhi-Qiang; Yang, Cai-Xia

    2016-01-01

    Meiotic maturation of mammalian oocytes is a precisely orchestrated and complex process. Dimethyl sulfoxide (DMSO), a widely used solvent, drug, and cryoprotectant, is capable of disturbing asymmetric cytokinesis of oocyte meiosis in mice. However, in pigs, DMSO’s effect on oocyte meiosis still remains unknown. We aimed to evaluate if DMSO treatment will affect porcine oocyte meiosis and the underlying molecular changes as well. Interestingly, we did not observe the formation of the large first polar body and symmetric division for porcine oocytes treated with DMSO, contrary to findings reported in mice. 3% DMSO treatment could inhibit cumulus expansion, increase nuclear abnormality, disturb spindle organization, decrease reactive oxygen species level, and elevate mitochondrial membrane potential of porcine oocytes. There was no effect on germinal vesicle breakdown rate regardless of DMSO concentration. 3% DMSO treatment did not affect expression of genes involved in spindle organization (Bub1 and Mad2) and apoptosis (NF-κB, Pten, Bcl2, Caspase3 and Caspase9), however, it significantly decreased expression levels of pluripotency genes (Oct4, Sox2 and Lin28) in mature oocytes. Therefore, we demonstrated that disturbed cumulus expansion, chromosome alignment, spindle organization and pluripotency gene expression could be responsible for DMSO-induced porcine oocyte meiotic arrest and the lower capacity of subsequent embryo development. Our results provide new insights on DMSO’s effect on porcine oocyte meiosis and raise safety concerns over DMSO’s usage on female reproduction in both farm animals and humans. PMID:27348312

  9. Some insight into the physical basis of the cryoprotective action of dimethyl sulfoxide and ethylene glycol.

    PubMed

    Murthy, S S

    1998-03-01

    In the determination of the solid-liquid phase equilibria in the aqueous mixtures of dimethyl sulfoxide (Me2SO) and ethylene glycol (EG) one often encounters the problem of equilibrium crystallization. In the present report the above aqueous solutions are equilibrated for crystallization in a dielectric cell during which the dielectric method is used for monitoring the extent of crystallization. The melting temperatures are then measured by using the dielectric technique in combination with the differential scanning calorimeter. The equilibrium phase diagram of Me2SO is found to be eutectic with two compounds formed of water and Me2SO in the ratio of 3:1 and 2:1. In the case of EG solutions it is eutectic with a 1:1 compound formation. It is suggested that the greater depression of the freezing point of water due to the complex formation and hence the attendant increase in the viscosity near the freezing point is the reason for the sluggish crystallization in these solutions. The variation of the glass transition temperature with composition is also examined in the above solutions along with the aqueous solutions of a number of other cryoprotectants. The glass-forming tendency of these solutions is discussed in terms of complex formation. An attempt is made to distinguish between good and bad glass-forming additives in terms of complex formation and ice clathrate formation. PMID:9527870

  10. Methionine sulfoxide reductase A regulates cell growth through the p53-p21 pathway

    SciTech Connect

    Choi, Seung Hee; Kim, Hwa-Young

    2011-12-09

    Highlights: Black-Right-Pointing-Pointer Down-regulation of MsrA inhibits normal cell proliferation. Black-Right-Pointing-Pointer MsrA deficiency leads to an increase in p21 by enhanced p53 acetylation. Black-Right-Pointing-Pointer Down-regulation of MsrA causes cell cycle arrest at the G{sub 2}/M stage. Black-Right-Pointing-Pointer MsrA is a regulator of cell growth that mediates the p53-p21 pathway. -- Abstract: MsrA is an oxidoreductase that catalyzes the stereospecific reduction of methionine-S-sulfoxide to methionine. Although MsrA is well-characterized as an antioxidant and has been implicated in the aging process and cellular senescence, its roles in cell proliferation are poorly understood. Here, we report a critical role of MsrA in normal cell proliferation and describe the regulation mechanism of cell growth by this protein. Down-regulation of MsrA inhibited cell proliferation, but MsrA overexpression did not promote it. MsrA deficiency led to an increase in p21, a major cyclin-dependent kinase inhibitor, thereby causing cell cycle arrest at the G{sub 2}/M stage. While protein levels of p53 were not altered upon MsrA deficiency, its acetylation level was significantly elevated, which subsequently activated p21 transcription. The data suggest that MsrA is a regulator of cell growth that mediates the p53-p21 pathway.

  11. Characteristics of Lithium Ions and Superoxide Anions in EMI-TFSI and Dimethyl Sulfoxide.

    PubMed

    Jung, Sun-ho; Federici Canova, Filippo; Akagi, Kazuto

    2016-01-28

    To clarify the microscopic effects of solvents on the formation of the Li(+)-O2(–) process of a Li–O2 battery, we studied the kinetics and thermodynamics of these ions in dimethyl sulfoxide (DMSO) and 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide (EMI-TFSI) using classical molecular dynamics simulation. The force field for ions–solvents interactions was parametrized by force matching first-principles calculations. Despite the solvation energies of the ions are similar in both solvents, their mobility is much higher in DMSO. The free-energy profiles also confirm that the formation and decomposition rates of Li(+)-O2(–) pairs are greater in DMSO than in EMI-TFSI. Our atomistic simulations point out that the strong structuring of EMI-TFSI around the ions is responsible for these differences, and it explains why the LiO2 clusters formed in DMSO during the battery discharge are larger than those in EMI-TFSI. Understanding the origin of such properties is crucial to aid the optimization of electrolytes for Li–O2 batteries. PMID:26689893

  12. Ion transport properties of magnesium bromide/dimethyl sulfoxide non-aqueous liquid electrolyte

    PubMed Central

    Sheha, E.

    2015-01-01

    Nonaqueous liquid electrolyte system based dimethyl sulfoxide DMSO and magnesium bromide (MgBr2) is synthesized via ‘Solvent-in-Salt’ method for the application in magnesium battery. Optimized composition of MgBr2/DMSO electrolyte exhibits high ionic conductivity of 10−2 S/cm at ambient temperature. This study discusses different concentrations from 0 to 5.4 M of magnesium salt, representing low, intermediate and high concentrations of magnesium salt which are examined in frequency dependence conductivity studies. The temperature dependent conductivity measurements have also been carried out to compute activation energy (Ea) by least square linear fitting of Arrhenius plot: ‘log σ − 1/T. The transport number of Mg2+ ion determined by means of a combination of d.c. and a.c. techniques is ∼0.7. A prototype cell was constructed using nonaqueous liquid electrolyte with Mg anode and graphite cathode. The Mg/graphite cell shows promising cycling. PMID:26843967

  13. Effects of Dimethyl Sulfoxide on Neuronal Response Characteristics in Deep Layers of Rat Barrel Cortex

    PubMed Central

    Soltani, Narjes; Mohammadi, Elham; Allahtavakoli, Mohammad; Shamsizadeh, Ali; Roohbakhsh, Ali; Haghparast, Abbas

    2016-01-01

    Introduction: Dimethyl sulfoxide (DMSO) is a chemical often used as a solvent for water-insoluble drugs. In this study, we evaluated the effect of intracerebroventricular (ICV) administration of DMSO on neural response characteristics (in 1200–1500 μm depth) of the rat barrel cortex. Methods: DMSO solution was prepared in 10% v/v concentration and injected into the lateral ventricle of rats. Neuronal spontaneous activity and neuronal responses to deflection of the principal whisker (PW) and adjacent whisker (AW) were recorded in barrel cortex. A condition test ratio (CTR) was used to measure inhibitory receptive fields in barrel cortex. Results: The results showed that both PW and AW evoked ON and OFF responses, neuronal spontaneous activity and inhibitory receptive fields did not change following ICV administration of DMSO. Conclusion: Results of this study suggest that acute ICV administration of 10% DMSO did not modulate the electrophysiological characteristics of neurons in the l deep ayers of rat barrel cortex. PMID:27563414

  14. Per-O-acetylation of cellulose in dimethyl sulfoxide with catalyzed transesterification.

    PubMed

    Chen, Chao-Yi; Chen, Ming-Jie; Zhang, Xue-Qin; Liu, Chuan-Fu; Sun, Run-Cang

    2014-04-16

    Cellulose acetylation was investigated in dimethyl sulfoxide (DMSO) with isopropenyl acetate (IPA) as acetylating reagent and 1,8-diazabicyclo[5,4,0]undec-7-ene (DBU) as catalyst at 70-130 °C for 3-12 h. The degree of substitution (DS) of acetylated cellulose was comparatively determined by titration and ¹H NMR and confirmed by FT-IR analysis. The results indicated that per-O-acetylation was achieved at >90 °C for a relatively long duration. The three well-resolved peaks of carbonyl carbons in ¹³C NMR spectra also provided evidence of per-O-acetylation. The solubility of cellulose acetates in common organic solvents was examined, and the result showed that chloroform can be an alternative choice as a solvent for fully acetylated cellulose formed in this study besides DMSO. The intrinsic viscosity of acetylated cellulose solution implied almost no degradation of cellulose during acetylation in DMSO except at higher temperature (130 °C) for a long time. PMID:24678805

  15. Mechanism of 1-Cys type methionine sulfoxide reductase A regeneration by glutaredoxin.

    PubMed

    Kim, Moon-Jung; Jeong, Jaeho; Jeong, Jihye; Hwang, Kwang Yeon; Lee, Kong-Joo; Kim, Hwa-Young

    2015-02-20

    Glutaredoxin (Grx), a major redox regulator, can act as a reductant of methionine sulfoxide reductase A (MsrA). However, the biochemical mechanisms involved in MsrA activity regeneration by Grx remain largely unknown. In this study, we investigated the regeneration mechanism of 1-Cys type Clostridium oremlandii MsrA (cMsrA) lacking a resolving Cys residue in a Grx-dependent assay. Kinetic analysis showed that cMsrA could be reduced by both monothiol and dithiol Grxs as efficiently as by in vitro reductant dithiothreitol. Our data revealed that the catalytic Cys sulfenic acid intermediate is not glutathionylated in the presence of the substrate, and that Grx instead directly formed a complex with cMsrA. Mass spectrometry analysis identified a disulfide bond between the N-terminal catalytic Cys of the active site of Grx and the catalytic Cys of cMsrA. This mixed disulfide bond could be resolved by glutathione. Based on these findings, we propose a model for regeneration of 1-Cys type cMsrA by Grx that involves no glutathionylation on the catalytic Cys of cMsrA. This mechanism contrasts with that of the previously known 1-Cys type MsrB. PMID:25600814

  16. QUANTIFICATION OF RESERVE POOL DOPAMINE IN METHIONINE SULFOXIDE REDUCTASE A NULL MICE

    PubMed Central

    Ortiz, Andrea N.; Oien, Derek B.; Moskovitz, Jackob; Johnson, Michael A.

    2012-01-01

    Methionine sulfoxide reductase A knockout (MsrA−/−) mice, which serve as a potential model for neurodegeneration, suffer from increased oxidative stress and have previously been found to have chronically elevated brain dopamine content levels relative to control mice. Additionally, these high levels parallel increased presynaptic dopamine release. In this work, fast-scan cyclic voltammetry at carbon-fiber microelectrodes was used to quantify striatal reserve pool dopamine in knockout mice and wild-type control mice. Reserve pool dopamine efflux, induced by amphetamine, was measured in brain slices from knockout and wild type mice in the presence of α-methyl-p-tyrosine, a dopamine synthesis inhibitor. Additionally, the stimulated release of reserve pool dopamine, mobilized by cocaine, was measured. Both efflux and stimulated release measurements were enhanced in slices from knockout mice, suggesting that these mice have greater reserve pool dopamine stores than wild-type and that these stores are effectively mobilized. Moreover, dopamine transporter labeling data indicate that the difference in measured dopamine efflux was likely not caused by altered dopamine transporter protein expression. Additionally, slices from MsrA−/− and wild-type mice were equally responsive to increasing extracellular calcium concentrations, suggesting that potential differences in either calcium entry or intracellular calcium handling are not responsible for increased reserve pool dopamine release. Collectively, these results demonstrate that MsrA−/− knockout mice maintain a larger dopamine reserve pool than wild-type control mice, and that this pool is readily mobilized. PMID:21219974

  17. Dissolution of brominated epoxy resins by dimethyl sulfoxide to separate waste printed circuit boards.

    PubMed

    Zhu, Ping; Chen, Yan; Wang, Liangyou; Qian, Guangren; Zhang, Wei Jie; Zhou, Ming; Zhou, Jin

    2013-03-19

    Improved methods are required for the recycling of waste printed circuit boards (WPCBs). In this study, WPCBs (1-1.5 cm(2)) were separated into their components using dimethyl sulfoxide (DMSO) at 60 °C for 45 min and a metallographic microscope was used to verify their delamination. An increased incubation time of 210 min yielded a complete separation of WPCBs into their components, and copper foils and glass fibers were obtained. The separation time decreased with increasing temperature. When the WPCB size was increased to 2-3 cm(2), the temperature required for complete separation increased to 90 °C. When the temperature was increased to 135 °C, liquid photo solder resists could be removed from the copper foil surfaces. The DMSO was regenerated by rotary decompression evaporation, and residues were obtained. Fourier transform infrared spectroscopy (FT-IR), thermal analysis, nuclear magnetic resonance, scanning electron microscopy, and energy-dispersive X-ray spectroscopy were used to verify that these residues were brominated epoxy resins. From FT-IR analysis after the dissolution of brominated epoxy resins in DMSO it was deduced that hydrogen bonding may play an important role in the dissolution mechanism. This novel technology offers a method for separating valuable materials and preventing environmental pollution from WPCBs. PMID:23398278

  18. Heterogeneity in binary mixtures of dimethyl sulfoxide and glycerol: fluorescence correlation spectroscopy.

    PubMed

    Chattoraj, Shyamtanu; Chowdhury, Rajdeep; Ghosh, Shirsendu; Bhattacharyya, Kankan

    2013-06-01

    Diffusion of four coumarin dyes in a binary mixture of dimethyl sulfoxide (DMSO) and glycerol is studied using fluorescence correlation spectroscopy (FCS). The coumarin dyes are C151, C152, C480, and C481. In pure DMSO, all the four dyes exhibit a very narrow (almost uni-modal) distribution of diffusion coefficient (Dt). In contrast, in the binary mixtures all of them display a bimodal distribution of Dt with broadly two components. One of the components of D(t) corresponds to the bulk viscosity. The other one is similar to that in pure DMSO. This clearly indicates the presence of two distinctly different nano-domains inside the binary mixture. In the first, the micro-environment of the solute consists of both DMSO and glycerol approximately at the bulk composition. The other corresponds to a situation where the first layer of the solute consists of DMSO only. The burst integrated fluorescence lifetime (BIFL) analysis also indicates presence of two micro-environments one of which resembles DMSO. The relative contribution of the DMSO-like environment obtained from the BIFL analysis is much larger than that obtained from FCS measurements. It is proposed that BIFL corresponds to an instantaneous environment in a small region (a few nm) around the probe. FCS, on the contrary, describes the long time trajectory of the probes in a region of dimension ~200 nm. The results are explained in terms of the theory of binary mixtures and recent simulations of binary mixtures containing DMSO. PMID:23758388

  19. Heterogeneity in binary mixtures of dimethyl sulfoxide and glycerol: Fluorescence correlation spectroscopy

    NASA Astrophysics Data System (ADS)

    Chattoraj, Shyamtanu; Chowdhury, Rajdeep; Ghosh, Shirsendu; Bhattacharyya, Kankan

    2013-06-01

    Diffusion of four coumarin dyes in a binary mixture of dimethyl sulfoxide (DMSO) and glycerol is studied using fluorescence correlation spectroscopy (FCS). The coumarin dyes are C151, C152, C480, and C481. In pure DMSO, all the four dyes exhibit a very narrow (almost uni-modal) distribution of diffusion coefficient (Dt). In contrast, in the binary mixtures all of them display a bimodal distribution of Dt with broadly two components. One of the components of Dt corresponds to the bulk viscosity. The other one is similar to that in pure DMSO. This clearly indicates the presence of two distinctly different nano-domains inside the binary mixture. In the first, the micro-environment of the solute consists of both DMSO and glycerol approximately at the bulk composition. The other corresponds to a situation where the first layer of the solute consists of DMSO only. The burst integrated fluorescence lifetime (BIFL) analysis also indicates presence of two micro-environments one of which resembles DMSO. The relative contribution of the DMSO-like environment obtained from the BIFL analysis is much larger than that obtained from FCS measurements. It is proposed that BIFL corresponds to an instantaneous environment in a small region (a few nm) around the probe. FCS, on the contrary, describes the long time trajectory of the probes in a region of dimension ˜200 nm. The results are explained in terms of the theory of binary mixtures and recent simulations of binary mixtures containing DMSO.

  20. Electrochemical machining of gold microstructures in LiCl/dimethyl sulfoxide.

    PubMed

    Ma, Xinzhou; Bán, Andreas; Schuster, Rolf

    2010-02-22

    LiCl/dimethyl sulfoxide (DMSO) electrolytes were applied for the electrochemical micromachining of Au. Upon the application of short potential pulses in the nanosecond range to a small carbon-fiber electrode, three-dimensional microstructures with high aspect ratios were fabricated. We achieved machining resolutions down to about 100 nm. In order to find appropriate machining parameters, that is, tool and workpiece rest potentials, the electrochemical behavior of Au in LiCl/DMSO solutions with and without addition of water was studied by cyclic voltammetry. In waterless electrolyte Au dissolves predominantly as Au(I), whereas upon the addition of water the formation of Au(III) becomes increasingly important. Because of the low conductivity of LiCl/DMSO compared with aqueous electrolytes, high machining precision is obtained with moderately short pulses. Furthermore, the redeposition of dissolved Au can be effectively avoided, since Au dissolution in LiCl/DMSO is highly irreversible. Both observations render LiCl/DMSO an appropriate electrolyte for the routine electrochemical micromachining of Au. PMID:20017182

  1. Covalent Immobilization of Polyoxotungstate on Alumina and Its Catalytic Generation of Sulfoxides.

    PubMed

    Hong, Lanlan; Win, Pyaesone; Zhang, Xuan; Chen, Wei; Miras, Haralampos N; Song, Yu-Fei

    2016-08-01

    The structural and chemical stabilities of immobilized polyoxometalate (POM)-containing catalysts are crucial factors for their industrial application. An alumina supported POM catalyst is prepared by using a facile condensation reaction between the trilacunary POM Na12 [α-P2 W15 O56 ]⋅24 H2 O (P2 W15 ) and the hydroxy groups on the surface of γ-Al2 O3 spheres under acidic conditions. The heterogeneous catalyst P2 W15 -Al2 O3 is characterized by a wide variety of techniques and shows excellent stability and highly efficient reactivity and selectivity for the oxygenation of thioethers to sulfoxides, which are a very useful intermediate in organic synthesis and the industrial preparation of drugs. Furthermore, P2 W15 -Al2 O3 can be recycled and reused at least ten times without any observable loss of its catalytic efficiency, mainly due to the covalent immobilization and high dispersion of P2 W15 on the γ-Al2 O3 surface. PMID:27400134

  2. A model to predict the permeation kinetics of dimethyl sulfoxide in articular cartilage.

    PubMed

    Yu, Xiaoyi; Chen, Guangming; Zhang, Shaozhi

    2013-02-01

    Cryopreservation of articular cartilage (AC) has excited great interest due to the practical surgical importance of this tissue. Characterization of permeation kinetics of cryoprotective agents (CPA) in AC is important for designing optimal CPA addition/removal protocols to achieve successful cryopreservation. Permeation is predominantly a mass diffusion process. Since the diffusivity is a function of temperature and concentration, analysis of the permeation problem would be greatly facilitated if a predictive method were available. This article describes, a model that was developed to predict the permeation kinetics of dimethyl sulfoxide (DMSO) in AC. The cartilage was assumed as a porous medium, and the effect(s) of composition and thermodynamic nonideality of the DMSO solution were considered in model development. The diffusion coefficient was correlated to the infinite dilution coefficients through a binary diffusion thermodynamic model. The UNIFAC model was used to evaluate the activity coefficient, the Vignes equation was employed to estimate the composition dependence of the diffusion coefficient, and the Siddiqi-Lucas correlation was applied to determine the diffusion coefficients at infinite dilution. Comparisons of the predicted overall DMSO uptake by AC with the experimental data over wide temperature and concentration ranges [1~37°C, 10~47% (w/w)] show that the model can accurately describe the permeation kinetics of DMSO in AC [coefficient of determination (R(2)): 0.961~0.996, mean relative error (MRE): 2.2~9.1%]. PMID:24845255

  3. Peptide methionine sulfoxide reductase contributes to the maintenance of adhesins in three major pathogens.

    PubMed Central

    Wizemann, T M; Moskovitz, J; Pearce, B J; Cundell, D; Arvidson, C G; So, M; Weissbach, H; Brot, N; Masure, H R

    1996-01-01

    Pathogenic bacteria rely on adhesins to bind to host tissues. Therefore, the maintenance of the functional properties of these extracellular macromolecules is essential for the pathogenicity of these microorganisms. We report that peptide methionine sulfoxide reductase (MsrA), a repair enzyme, contributes to the maintenance of adhesins in Streptococcus pneumoniae, Neisseria gonorrhoeae, and Escherichia coli. A screen of a library of pneumococcal mutants for loss of adherence uncovered a MsrA mutant with 75% reduced binding to GalNAcbeta1-4Gal containing eukaryotic cell receptors that are present on type II lung cells and vascular endothelial cells. Subsequently, it was shown that an E. coli msrA mutant displayed decreased type I fimbriae-mediated, mannose-dependent, agglutination of erythrocytes. Previous work [Taha, M. K., So, M., Seifert, H. S., Billyard, E. & Marchal, C. (1988) EMBO J. 7, 4367-4378] has shown that mutants with defects in the pilA-pilB locus from N. gonorrhoeae were altered in their production of type IV pili. We show that pneumococcal MsrA and gonococcal PilB expressed in E. coli have MsrA activity. Together these data suggest that MsrA is required for the proper expression or maintenance of functional adhesins on the surfaces of these three major pathogenic bacteria. Images Fig. 2 Fig. 3 Fig. 4 PMID:8755589

  4. X-Ray Absorption Spectroscopic Characterization of the Molybdenum Site of 'Escherichia Coli' Dimethyl Sulfoxide Reductase

    SciTech Connect

    George, G.N.; Doonan, C.J.; Rothery, R.A.; Boroumand, N.; Weiner, J.H.; /Saskatchewan U. /Alberta U.

    2007-07-09

    Structural studies of dimethyl sulfoxide (DMSO) reductases were hampered by modification of the active site during purification. We report an X-ray absorption spectroscopic analysis of the molybdenum active site of Escherichia coli DMSO reductase contained within its native membranes. The enzyme in these preparations is expected to be very close to the form found in vivo. The oxidized active site was found to have four Mo-S ligands at 2.43 angstroms, one Mo=O at 1.71 angstroms, and a longer Mo-O at 1.90 angstroms. We conclude that the oxidized enzyme is a monooxomolybdenum(VI) species coordinated by two molybdopterin dithiolenes and a serine. The bond lengths determined for E. coli DMSO reductase are very similar to those determined for the well-characterized Rhodobacter sphaeroides DMSO reductase, suggesting similar active site structures for the two enzymes. Furthermore, our results suggest that the form found in vivo is the monooxobis(molybdopterin) species.

  5. Molecular structure and adsorption of dimethyl sulfoxide at the surface of aqueous solutions

    SciTech Connect

    Allen, H.C.; Gragson, D.E.; Richmond, G.L.

    1999-01-28

    Surface vibrational sum frequency generation (VSFG) spectroscopy complemented with surface tension measurements has been utilized to probe the air/dimethyl sulfoxide (DMSO) interface as a function of DMSO concentration in water. For the neat DMSO surface, the DMSO methyl groups extend away from the liquid phase and VSFG polarization studies show that the methyl transition dipole moments of pure DMSO are on average oriented a maximum of 55{degree} from the surface normal. A blue shift of the methyl symmetric stretch is observed with decreasing DMSO concentration and attributed to an electronic interaction between the sulfur and the methyl groups of DMSO. From surface tension data of the aqueous DMSO system, it is shown the DMSO number densities are higher at the surface of DMSO-water solutions relative to bulk DMSO concentrations revealing surface partitioning effects. Structural changes of surface DMSO are discussed in terms of monomers, dimers, and clusters which could account for the large differences in VSFG intensities and surface number densities. From surface tension measurements and utilizing DMSO activities, {Delta}G{sub ads}{sup 0} is calculated to be {minus}19.8 ({+-}0.4) kJ/mol.

  6. Investigation of the interaction of dimethyl sulfoxide with lipid membranes by small-angle neutron scattering

    SciTech Connect

    Gorshkova, J. E. Gordeliy, V. I.

    2007-05-15

    The influence of dimethyl sulfoxide (CH{sub 3}){sub 2}SO (DMSO) on the structure of membranes of 1,2-dimiristoyl-sn-glycero-3-phosphatidylcholine (DMPC) in an excess of a water-DMSO solvent is investigated over a wide range of DMSO molar concentrations 0.0 {<=} X{sub DMSO} {<=} 1.0 at temperatures T = 12.5 and 55 deg. C. The dependences of the repeat distance d of multilamellar membranes and the thickness d{sub b} of single vesicles on the molar concentration X{sub DMSO} in the L{sub {beta}}{sub '} gel and L{sub {alpha}} liquid-crystalline phases are determined by small-angle neutron scattering. The intermembrane distance d{sub s} is determined from the repeat distance d and the membrane thickness d{sub b}. It is shown that an increase in the molar concentration X{sub DMSO} leads to a considerable decrease in the intermembrane distance and that, at X{sub DMSO} = 0.4, the neighboring membranes are virtually in steric contact with each other. The use of the deuterated phospholipid (DMSO-D6) and the contrast variation method makes it possible, for the first time, to determine the number of DMSO molecules strongly bound to the membrane.

  7. Endothelium-Dependent and -Independent Vasodilator Effects of Dimethyl Sulfoxide in Rat Aorta.

    PubMed

    Kaneda, Takeharu; Sasaki, Noriyasu; Urakawa, Norimoto; Shimizu, Kazumasa

    2016-01-01

    This study examined the mechanism of vasorelaxation induced by dimethyl sulfoxide (DMSO) in endothelium-intact and -denuded rat aorta. DMSO (0.1-3%) inhibited phenylephrine (PE, 1 μmol/l)-induced contraction in a dose-dependent manner. However, this relaxation was lower in the absence of the endothelium. Increase in DMSO-induced relaxation in the presence of the endothelium was attenuated by preincubation in L-NG-nitroarginine methyl ester (L-NAME, 100 μmol/l) and by the removal of the endothelium. In the aorta with endothelium, DMSO (3%) and CCh (3 μmol/l) increased cGMP contents, significantly and L-NAME (100 μmol/l) inhibited the DMSO-induced increases of cGMP. In fura 2-loaded endothelium-denuded aorta, cumulative application of DMSO (1-3%) inhibited PE-induced muscle tension; however, this application did not affect the [Ca2+]i level. In PE-precontracted endothelium-denuded aorta, relaxation responses to fasudil were significantly less in the presence of DMSO compared to the control. These results suggest that DMSO causes relaxation by increasing the cGMP content in correlation with the release of NO from endothelial cells and by decreasing the Ca2+ sensitivity of contractile elements partly via inhibiting Rho-kinase in rat aorta. PMID:26836124

  8. A catalase-peroxidase for oxidation of β-lactams to their (R)-sulfoxides.

    PubMed

    Sangar, Shefali; Pal, Mohan; Moon, Lomary S; Jolly, Ravinder S

    2012-07-01

    In this communication we report for the first time a biocatalytic method for stereoselective oxidation of β-lactams, represented by penicillin-G, penicillin-V and cephalosporin-G to their (R)-sulfoxides. The method involves use of a bacterium, identified as Bacillus pumilis as biocatalyst. The enzyme responsible for oxidase activity has been purified and characterized as catalase-peroxidase (KatG). KatG of B. pumilis is a heme containing protein showing characteristic heme spectra with soret peak at 406 nm and visible peaks at 503 and 635 nm. The major properties that distinguish B. pumilis KatG from other bacterial KatGs are (i) it is a monomer and contains one heme per monomer, whereas KatGs of other bacteria are dimers or tetramers and have low heme content of about one per dimer or two per tetramer and (ii) its 12-residue, N-terminal sequence obtained by Edman degradation did not show significant similarity with any of known KatGs. PMID:21996477

  9. Specific reduction of N,N-dimethylnitrosamine mutagenicity in Drosophila melanogaster by dimethyl sulfoxide

    SciTech Connect

    Brodberg, R.K.; Mitchell, M.J.; Smith, S.L.; Woodruff, R.C.

    1988-01-01

    Dimethyl sulfoxide (DMSO) used as a solvent has been observed to complicate mutagenicity screens by interacting with tested chemicals to yield false positive or negatives. The authors have used DMSO as a solvent in the Drosophila melanogaster recessive sex-linked lethal mutation assay and find that it reduces, but does not abolish, the detectable mutagenicity of N,N-dimethylnitrosamine (DMN). Its use as a solvent with procarbazine, another promutagen, shows no effect on mutagenicity in Drosophila. DMSO does not exhibit a general inhibitory action on microsome activity when ecdysone 20-monooxygenase activity is used as a measure of cytochrome P-450 activity. They were unable to detect the low DMN demethylase activity in the strain used. Hence, the inhibitory effect of DMSO in Drosophila at both the physiological and biological level appears to be limited and not general in action. Because DMN and DMSO are similar in structure, it is possible that DMSO is interacting with a DMN demethylase in Drosophila. This might lead to a reduction in the conversion of DMN to a mutagen. Consequently, from the results of this study and others DMSO should be used cautiously as a solvent in Drosophila mutagen screening.

  10. Dimethyl Sulfoxide (DMSO) Exacerbates Cisplatin-induced Sensory Hair Cell Death in Zebrafish (Danio rerio)

    PubMed Central

    Gleichman, Julia S.; Kramer, Matthew D.; Wang, Qi; Sibrian-Vazquez, Martha; Strongin, Robert M.; Steyger, Peter S.; Cotanche, Douglas A.; Matsui, Jonathan I.

    2013-01-01

    Inner ear sensory hair cells die following exposure to aminoglycoside antibiotics or chemotherapeutics like cisplatin, leading to permanent auditory and/or balance deficits in humans. Zebrafish (Danio rerio) are used to study drug-induced sensory hair cell death since their hair cells are similar in structure and function to those found in humans. We developed a cisplatin dose-response curve using a transgenic line of zebrafish that expresses membrane-targeted green fluorescent protein under the control of the Brn3c promoter/enhancer. Recently, several small molecule screens have been conducted using zebrafish to identify potential pharmacological agents that could be used to protect sensory hair cells in the presence of ototoxic drugs. Dimethyl sulfoxide (DMSO) is typically used as a solvent for many pharmacological agents in sensory hair cell cytotoxicity assays. Serendipitously, we found that DMSO potentiated the effects of cisplatin and killed more sensory hair cells than treatment with cisplatin alone. Yet, DMSO alone did not kill hair cells. We did not observe the synergistic effects of DMSO with the ototoxic aminoglycoside antibiotic neomycin. Cisplatin treatment with other commonly used organic solvents (i.e. ethanol, methanol, and polyethylene glycol 400) also did not result in increased cell death compared to cisplatin treatment alone. Thus, caution should be exercised when interpreting data generated from small molecule screens since many compounds are dissolved in DMSO. PMID:23383324

  11. Dipole-bound anions of carbonyl, nitrile, and sulfoxide containing molecules

    NASA Astrophysics Data System (ADS)

    Hammer, Nathan I.; Diri, Kadir; Jordan, Kenneth D.; Desfrançois, Charles; Compton, Robert N.

    2003-08-01

    Dipole-bound anions of 27 molecules containing either a carbonyl, nitrile, or sulfoxide group were studied using Rydberg electron transfer (RET) reactions with rubidium atoms excited to ns 2S and nd 2D excited states. The electron affinity of each molecule was obtained from the Rydberg state, nmax*, that gave the largest negative ion yield using the empirical relationship electron affinity=23/nmax*2.8 eV as well as from fitting the charge exchange profile to a theoretical curve crossing model. Electron affinities for the low dipole moment molecules (carbonyls) were also deduced from measurements of the electric field required to detach the electron from the anion. Calculations of the electron affinities for some of the nitriles at the coupled-cluster level of theory were performed. The dependencies of the electron affinity upon dipole moment, polarizability, dispersion interaction, conformation, and geometry of the molecules were investigated. It was found that a higher dipole moment generally results in a higher electron affinity. However, for molecules with similar dipole moments, other factors such as polarizability and the dispersion interaction play an important role. The effect of collision velocity on the creation of these anions is also studied through the use of different carrier gases (H2, He, Ne, Ar, Kr, Xe) in the nozzle jet expansion. Competition between RET and collisional detachment is observed and discussed qualitatively.

  12. The Effect of Dimethyl Sulfoxide on Supercoiled DNA Relaxation Catalyzed by Type I Topoisomerases

    PubMed Central

    Lv, Bei; Dai, Yunjia; Liu, Ju; Zhuge, Qiang; Li, Dawei

    2015-01-01

    The effects of dimethyl sulfoxide (DMSO) on supercoiled plasmid DNA relaxation catalyzed by two typical type I topoisomerases were investigated in our studies. It is shown that DMSO in a low concentration (less than 20%, v/v) can induce a dose-related enhancement of the relaxation efficiency of Escherichia coli topoisomerase I (type IA). Conversely, obvious inhibitory effect on the activity of calf thymus topoisomerase I (type IB) was observed when the same concentration of DMSO is used. In addition, our studies demonstrate that 20% DMSO has an ability to reduce the inhibitory effect on EcTopo I, which was induced by double-stranded oligodeoxyribonucleotides while the same effect cannot be found in the case of CtTopo I. Moreover, our AFM examinations suggested that DMSO can change the conformation of negatively supercoiled plasmid by creating some locally loose regions in DNA molecules. Combining all the lines of evidence, we proposed that DMSO enhanced EcTopo I relaxation activity by (1) increasing the single-stranded DNA regions for the activities of EcTopo I in the early and middle stages of the reaction and (2) preventing the formation of double-stranded DNA-enzyme complex in the later stage, which can elevate the effective concentration of the topoisomerase in the reaction solution. PMID:26682217

  13. Dimethyl sulfoxide and sodium bicarbonate in the treatment of refractory cancer pain.

    PubMed

    Hoang, Ba X; Tran, Dao M; Tran, Hung Q; Nguyen, Phuong T M; Pham, Tuan D; Dang, Hong V T; Ha, Trung V; Tran, Hau D; Hoang, Cuong; Luong, Khue N; Shaw, D Graeme

    2011-01-01

    Pain is a major concern of cancer patients and a significant problem for therapy. Pain can become a predominant symptom in advanced cancers. In this open-label clinical study, the authors have treated 26 cancer patients who have been declared as terminal without the option of conventional treatment. These patients suffered from high levels of pain that was poorly managed by all available interventional approaches recommended by World Health Organization (WHO) guideline. The results indicate that intravenous infusion of dimethyl sulfoxide (DMSO) and sodium bicarbonate (SB) solution can be a viable, effective, and safe treatment for refractory pain in cancer patients. These patients had pain due to the disease progression and complication of chemotherapy and radiation. Moreover, the preliminary clinical outcome of 96-day follow-up suggests that the application of DMSO and SB solution intravenously could lead to better quality of life for patients with nontreatable terminal cancers. The data of this clinical observation indicates that further research and application of the DMSO and SB combination may help the development of an effective, safe, and inexpensive therapy to manage cancer pain. PMID:21426213

  14. Swelling behavior of halthane 73-18 polyurethane adhesive in dimethyl sulfoxide (DMSO)

    SciTech Connect

    LeMay, J. D., LLNL

    1996-06-01

    To insure safe performance during the launch and flight of the W79 Artillery Fired Atomic Projectile (AFAP), the assembly gaps in the high explosive assembly were filled with a continuous film of polyurethane elastomer adhesive called Halthane 73-18. To disassemble bonded weapons like the W79, Lawrence Livermore and Mason & Hanger, Pantex Plant have developed a chemical dissolution process that safely removes the high explosive, thereby facilitating the recovery of the pit. The solvent of choice for the W79 AFAP was dimethyl sulfoxide (DMSO). In the W79 dissolution process, a continuous spray of DMSO is emitted through nozzles mounted in manifold assembly that encircles the HE assembly. The operating pressure and temperature of the DMSO are less than 100 psig and less than 160{degrees}F. Although warm DMSO readily dissolves the LX-10{sup 1} explosive, it cannot dissolve the Halthane 73-18 adhesive due to its chemically crosslinked structure. DMSO does, however, swell the Halthane adhesive. The resulting swollen films are soft and unable to support their own weight, yet they are not necessarily so fragile that they will tear or shred readily under the force of the DMSO spray. Indeed, the swollen Halthane films encountered in several W79 Type 6B 2048 units tested in the Pantex Workstation proved to be quite tenacious. They remained intact under the action of DMSO spray and became an encapsulating barrier that shielded the remaining undissolved HE. This effectively stopped the dissolution process, forcing manual removal in order to complete the dissolution process. By comparison, the swollen Halthane film was readily shredded and eliminated under the action of the DMSO spray nozzles in tests at LLNL in workstation of a different design. This apparent difference in response is the subject of this report.

  15. Combined experimental and theoretical investigation of interactions between kaolinite inner surface and intercalated dimethyl sulfoxide

    NASA Astrophysics Data System (ADS)

    Zhang, Shuai; Liu, Qinfu; Cheng, Hongfei; Zeng, Fangui

    2015-03-01

    Kaolinite intercalation complex with dimethyl sulfoxide (DMSO) was investigated by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and thermogravimetry-differential scanning calorimetry (TG-DSC) combined with molecular dynamics simulation. The bands assigned to the OH stretching of inner surface of kaolinite were significantly perturbed after intercalation of DMSO into kaolinite. Additionally, the bands attributed to the vibration of gibbsite-like layers of kaolinite shifted to the lower wave number, indicating that the intercalated DMSO were strongly hydrogen bonded to the alumina octahedral surface of kaolinite. The slightly decreased intensity of 1031 cm-1 and 1016 cm-1 band due to the in-plane vibration of Sisbnd O of kaolinite revealed that some DMSO molecules formed weak hydrogen bonds with the silicon tetrahedral surface of kaolinite. Based on the TG result of kaolinite-DMSO intercalation complex, the formula of A12Si2O5(OH)4(DMSO)0.7 was obtained, with which the kaolinite-DMSO complex model was constructed. The molecular dynamics simulation of kaolinite-DMSO complex directly confirmed the monolayer structure of DMSO in interlayer space of kaolinite, where the DMSO arranged almost parallel with kaolinite basal surface with all methyl groups being distributed near the interlayer midplane and oxygen atoms orienting toward to the alumina octahedral surface. The radial distribution function between kaolinite and intercalated DMSO verified the strong hydrogen bonds forming between hydroxyl hydrogen atoms of alumina octahedral surface and oxygen atoms of DMSO. Moreover, some methyl groups of DMSO were weakly hydrogen bonded to the oxygen atoms of silicon tetrahedral surface through the hydrogen atoms. The mean square displacement of DMSO oxygen atoms and hydrogen atoms in z direction kept unchanged during the simulation time because of the hydrogen-bond interaction between inner surface of kaolinite and DMSO, which constrained the mobility

  16. Characterization of methionine oxidation and methionine sulfoxide reduction using methionine-rich cysteine-free proteins

    PubMed Central

    2012-01-01

    Background Methionine (Met) residues in proteins can be readily oxidized by reactive oxygen species to Met sulfoxide (MetO). MetO is a promising physiological marker of oxidative stress and its inefficient repair by MetO reductases (Msrs) has been linked to neurodegeneration and aging. Conventional methods of assaying MetO formation and reduction rely on chromatographic or mass spectrometry procedures, but the use of Met-rich proteins (MRPs) may offer a more streamlined alternative. Results We carried out a computational search of completely sequenced genomes for MRPs deficient in cysteine (Cys) residues and identified several proteins containing 20% or more Met residues. We used these MRPs to examine Met oxidation and MetO reduction by in-gel shift assays and immunoblot assays with antibodies generated against various oxidized MRPs. The oxidation of Cys-free MRPs by hydrogen peroxide could be conveniently monitored by SDS-PAGE and was specific for Met, as evidenced by quantitative reduction of these proteins with Msrs in DTT- and thioredoxin-dependent assays. We found that hypochlorite was especially efficient in oxidizing MRPs. Finally, we further developed a procedure wherein antibodies made against oxidized MRPs were isolated on affinity resins containing same or other oxidized or reduced MRPs. This procedure yielded reagents specific for MetO in these proteins, but proved to be ineffective in developing antibodies with broad MetO specificity. Conclusion Our data show that MRPs provide a convenient tool for characterization of Met oxidation, MetO reduction and Msr activities, and could be used for various aspects of redox biology involving reversible Met oxidation. PMID:23088625

  17. Morphological study of rat skin flaps treated with subcutaneous dimethyl sulfoxide combined with hyperbaric oxygen therapy.

    PubMed

    Almeida, K G; Oliveira, R J; Dourado, D M; Filho, E A; Fernandes, W S; Souza, A S; Araújo, F H S

    2015-01-01

    This study investigated the effects of hyperbaric oxygen therapy (HBOT) and dimethyl sulfoxide (DMSO) in tissue necrosis, genotoxicity, and cell apoptosis. Random skin flaps were made in 50 male Wistar rats, randomly divided into the following groups. Control group (CT), wherein a rectangular skin section (2 x 8 cm) was dissected from the dorsal muscle layer, preserving the cranial vessels, lifted, and refixed to the bed; distilled water (DW) group, in which DW was injected into the distal half of the skin flap; DMSO group, wherein 5% DMSO was injected; HBOT group, comprising animals treated only with HBOT; and HBOT + DMSO group, comprising animals treated with 100% oxygen at 2.5 atmospheres absolute for 1 h, 2 h after the experiment, daily for 10 consecutive days. A skinflap specimen investigated by microscopy. The percentage of necrosis was not significantly different between groups. The cell viability index was significantly different between groups (P < 0.001): 87.40% (CT), 86.20% (DW), 84.60% (DMSO), 86.60% (DMSO + HBO), and 91% (HBO) (P < 0.001), as was the cell apoptosis index of 12.60 (CT), 12.00 (DW), 15.40 (DMSO), 9.00 (HBO), and 12.00 (DMSO + HBO) (P < 0.001). The genotoxicity test revealed the percentage of cells with DNA damage to be 22.80 (CT), 22.60 (DW), 26.00 (DMSO), 8.80 (DMSO + HBO), and 7.20 (HBO) (P < 0.001). Although the necrotic area was not different between groups, there was a significant reduction in the cellular DNA damage and apoptosis index in the HBOT group. PMID:26782463

  18. Gene expression and physiological role of Pseudomonas aeruginosa methionine sulfoxide reductases during oxidative stress.

    PubMed

    Romsang, Adisak; Atichartpongkul, Sopapan; Trinachartvanit, Wachareeporn; Vattanaviboon, Paiboon; Mongkolsuk, Skorn

    2013-08-01

    Pseudomonas aeruginosa PAO1 has two differentially expressed methionine sulfoxide reductase genes: msrA (PA5018) and msrB (PA2827). The msrA gene is expressed constitutively at a high level throughout all growth phases, whereas msrB expression is highly induced by oxidative stress, such as sodium hypochlorite (NaOCl) treatment. Inactivation of either msrA or msrB or both genes (msrA msrB mutant) rendered the mutants less resistant than the parental PAO1 strain to oxidants such as NaOCl and H2O2. Unexpectedly, msr mutants have disparate resistance patterns when exposed to paraquat, a superoxide generator. The msrA mutant had a higher paraquat resistance level than the msrB mutant, which had a lower paraquat resistance level than the PAO1 strain. The expression levels of msrA showed an inverse correlation with the paraquat resistance level, and this atypical paraquat resistance pattern was not observed with msrB. Virulence testing using a Drosophila melanogaster model revealed that the msrA, msrB, and, to a greater extent, msrA msrB double mutants had an attenuated virulence phenotype. The data indicate that msrA and msrB are essential genes for oxidative stress protection and bacterial virulence. The pattern of expression and mutant phenotypes of P. aeruginosa msrA and msrB differ from previously characterized msr genes from other bacteria. Thus, as highly conserved genes, the msrA and msrB have diverse expression patterns and physiological roles that depend on the environmental niche where the bacteria thrive. PMID:23687271

  19. Effect of Dimethyl Sulfoxide and Melatonin on the Isolation of Human Primary Hepatocytes.

    PubMed

    Solanas, Estela; Sostres, Carlos; Serrablo, Alejandro; García-Gil, Agustín; García, Joaquín J; Aranguren, Francisco J; Jiménez, Pilar; Hughes, Robin D; Serrano, María T

    2014-01-01

    The availability of fully functional human hepatocytes is critical for progress in human hepatocyte transplantation and the development of bioartificial livers and in vitro liver systems. However, the cell isolation process impairs the hepatocyte status and determines the number of viable cells that can be obtained. This study aimed to evaluate the effects of using dimethyl sulfoxide (DMSO) and melatonin in the human hepatocyte isolation protocol. Human hepatocytes were isolated from liver pieces resected from 10 patients undergoing partial hepatectomy. Each piece was dissected into 2 equally sized pieces and randomized, in 5 of 10 isolations, to perfusion with 1% DMSO-containing perfusion buffer or buffer also containing 5 mM melatonin using the 2-step collagenase perfusion technique (experiment 1), and in the other 5 isolations to standard perfusion or perfusion including 1% DMSO (experiment 2). Tissues perfused with DMSO yielded 70.6% more viable hepatocytes per gram of tissue (p = 0.076), with a 26.1% greater albumin production (p < 0.05) than those perfused with control buffer. Melatonin did not significantly affect (p > 0.05) any of the studied parameters, but cell viability, dehydrogenase activity, albumin production, urea secretion, and 7-ethoxycoumarin O-deethylase activity were slightly higher in cells isolated with melatonin-containing perfusion buffer compared to those isolated with DMSO. In conclusion, addition of 1% DMSO to the hepatocyte isolation protocol could improve the availability and functionality of hepatocytes for transplantation, but further studies are needed to clarify the mechanisms involved. PMID:26381499

  20. Structure and hydrogen bond dynamics of water-dimethyl sulfoxide mixtures by computer simulations

    NASA Astrophysics Data System (ADS)

    Luzar, Alenka; Chandler, David

    1993-05-01

    We have used two different force field models to study concentrated dimethyl sulfoxide (DMSO)-water solutions by molecular dynamics. The results of these simulations are shown to compare well with recent neutron diffraction experiments using H/D isotope substitution [A. K. Soper and A. Luzar, J. Chem. Phys. 97, 1320 (1992)]. Even for the highly concentrated 1 DMSO : 2 H2O solution, the water hydrogen-hydrogen radial distribution function, gHH(r), exhibits the characteristic tetrahedral ordering of water-water hydrogen bonds. Structural information is further obtained from various partial atom-atom distribution functions, not accessible experimentally. The behavior of water radial distribution functions, gOO(r) and gOH(r) indicate that the nearest neighbor correlations among remaining water molecules in the mixture increase with increasing DMSO concentration. No preferential association of methyl groups on DMSO is detected. The pattern of hydrogen bonding and the distribution of hydrogen bond lifetimes in the simulated mixtures is further investigated. Molecular dynamics results show that DMSO typically forms two hydrogen bonds with water molecules. Hydrogen bonds between DMSO and water molecules are longer lived than water-water hydrogen bonds. The hydrogen bond lifetimes determined by reactive flux correlation function approach are about 5 and 3 ps for water-DMSO and water-water pairs, respectively, in 1 DMSO : 2 H2O mixture. In contrast, for pure water, the hydrogen bond lifetime is about 1 ps. We discuss these times in light of experimentally determined rotational relaxation times. The relative values of the hydrogen bond lifetimes are consistent with a statistical (i.e., transition state theory) interpretation.

  1. Thermodynamic and Spectroscopic Studies of Lanthanides(III) Complexation with Polyamines in Dimethyl Sulfoxide

    SciTech Connect

    Di Bernardo, Plinio; Zanonato, Pier Luigi; Melchior, Andrea; Portanova, Roberto; Tolazzi, Marilena; Choppin, Gregory R.; Wang, Zheming

    2008-01-01

    The thermodynamic parameters of complexation of Ln(III) cations with tris(2-aminoethyl)amine (tren) and tetraethylenepentamine (tetren) were determined in dimethyl sulfoxide (DMSO) by potentiometry and calorimetry. The excitation and emission spectra and luminescence decay constants of Eu3+ and Tb3+ complexed by tren and tetren, as well as those of the same lanthanides(III) complexed with diethylenetriamine (dien) and triethylenetetramine (trien), were also obtained in the same solvent. The combination of thermodynamic and spectroscopic data showed that, in the 1:1 complexes, all nitrogens of the ligands bound to the lanthanides except in the case of tren, in which only pendant N bound. For the larger ligands (trien, tren, tetren) in the higher complexes (ML2), there was less complete binding by available donors, presumably due to steric crowding. FT-IR studies were carried out in an acetonitrile/DMSO mixture, suitably chosen in order to follow the changes in the primary solvation sphere of lanthanide(III) due to complexation of amine ligands. Results show that the mean number of molecules of DMSO removed from the inner coordination sphere of lanthanides(III) is lower than ligand denticity and that the coordination number of the metal ions increases with amine complexation from ~8 to ~10. Independently of the number and structure of the amines, linear trends, similar for all lanthanides, were obtained by plotting the values of ΔGj°, ΔHj° and TΔSj° for the complexation of ethylenediamine (en), dien, trien, tren and tetren as a function of the number of amine metal-coordinated nitrogen atoms. The main factors on which the thermodynamic functions of lanthanide(III) complexation reactions in DMSO depend are discussed.

  2. Sulfoxides, Analogues of L-Methionine and L-Cysteine As Pro-Drugs against Gram-Positive and Gram-Negative Bacteria.

    PubMed

    Anufrieva, N V; Morozova, E A; Kulikova, V V; Bazhulina, N P; Manukhov, I V; Degtev, D I; Gnuchikh, E Yu; Rodionov, A N; Zavilgelsky, G B; Demidkina, T V

    2015-01-01

    The problem of resistance to antibiotics requires the development of new classes of broad-spectrum antimicrobial drugs. The concept of pro-drugs allows researchers to look for new approaches to obtain effective drugs with improved pharmacokinetic and pharmacodynamic properties. Thiosulfinates, formed enzymatically from amino acid sulfoxides upon crushing cells of genus Allium plants, are known as antimicrobial compounds. The instability and high reactivity of thiosulfinates complicate their use as individual antimicrobial compounds. We propose a pharmacologically complementary pair: an amino acid sulfoxide pro-drug and vitamin B6 - dependent methionine γ-lyase, which metabolizes it in the patient's body. The enzyme catalyzes the γ- and β-elimination reactions of sulfoxides, analogues of L-methionine and L-cysteine, which leads to the formation of thiosulfinates. In the present work, we cloned the enzyme gene from Clostridium sporogenes. Ionic and tautomeric forms of the internal aldimine were determined by lognormal deconvolution of the holoenzyme spectrum and the catalytic parameters of the recombinant enzyme in the γ- and β-elimination reactions of amino acids, and some sulfoxides of amino acids were obtained. For the first time, the possibility of usage of the enzyme for effective conversion of sulfoxides was established and the antimicrobial activity of thiosulfinates against Gram-negative and Gram-positive bacteria in situ was shown. PMID:26798500

  3. Sulfoxides, Analogues of L-Methionine and L-Cysteine As Pro-Drugs against Gram-Positive and Gram-Negative Bacteria

    PubMed Central

    Anufrieva, N. V.; Morozova, E. A.; Kulikova, V. V.; Bazhulina, N. P.; Manukhov, I. V.; Degtev, D. I.; Gnuchikh, E. Yu.; Rodionov, A. N.; Zavilgelsky, G. B.; Demidkina, T. V.

    2015-01-01

    The problem of resistance to antibiotics requires the development of new classes of broad-spectrum antimicrobial drugs. The concept of pro-drugs allows researchers to look for new approaches to obtain effective drugs with improved pharmacokinetic and pharmacodynamic properties. Thiosulfinates, formed enzymatically from amino acid sulfoxides upon crushing cells of genus Allium plants, are known as antimicrobial compounds. The instability and high reactivity of thiosulfinates complicate their use as individual antimicrobial compounds. We propose a pharmacologically complementary pair: an amino acid sulfoxide pro-drug and vitamin B6 – dependent methionine γ-lyase, which metabolizes it in the patient’s body. The enzyme catalyzes the γ- and β-elimination reactions of sulfoxides, analogues of L-methionine and L-cysteine, which leads to the formation of thiosulfinates. In the present work, we cloned the enzyme gene from Clostridium sporogenes. Ionic and tautomeric forms of the internal aldimine were determined by lognormal deconvolution of the holoenzyme spectrum and the catalytic parameters of the recombinant enzyme in the γ- and β-elimination reactions of amino acids, and some sulfoxides of amino acids were obtained. For the first time, the possibility of usage of the enzyme for effective conversion of sulfoxides was established and the antimicrobial activity of thiosulfinates against Gram-negative and Gram-positive bacteria in situ was shown. PMID:26798500

  4. Versatile C(sp(2) )-C(sp(3) ) Ligand Couplings of Sulfoxides for the Enantioselective Synthesis of Diarylalkanes.

    PubMed

    Dean, William M; Šiaučiulis, Mindaugas; Storr, Thomas E; Lewis, William; Stockman, Robert A

    2016-08-16

    The reaction of chiral (hetero)aryl benzyl sulfoxides with Grignard reagents affords enantiomerically pure diarylalkanes in up to 98 % yield and greater than 99.5 % enantiomeric excess. This ligand coupling reaction is tolerant to multiple substitution patterns and provides access to diverse areas of chemical space in three operationally simple steps from commercially available reagents. This strategy provides orthogonal access to electron-deficient heteroaromatic compounds, which are traditionally synthesized by transition metal catalyzed cross-couplings, and circumvents common issues associated with proto-demetalation and β-hydride elimination. PMID:27435802

  5. Freezing of Apheresis Platelet Concentrates in 6% Dimethyl Sulfoxide: The First Preliminary Study in Turkey

    PubMed Central

    Yılmaz, Soner; Çetinkaya, Rıza Aytaç; Eker, İbrahim; Ünlü, Aytekin; Uyanık, Metin; Tapan, Serkan; Pekoğlu, Ahmet; Pekel, Aysel; Erkmen, Birgül; Muşabak, Uğur; Yılmaz, Sebahattin; Avcı, İsmail Yaşar; Avcu, Ferit; Kürekçi, Emin; Eyigün, Can Polat

    2016-01-01

    Objective: Transfusion of platelet suspensions is an essential part of patient care for certain clinical indications. In this pioneering study in Turkey, we aimed to assess the in vitro hemostatic functions of platelets after cryopreservation. Materials and Methods: Seven units of platelet concentrates were obtained by apheresis. Each apheresis platelet concentrate (APC) was divided into 2 equal volumes and frozen with 6% dimethyl sulfoxide (DMSO). The 14 frozen units of APCs were kept at -80 °C for 1 day. APCs were thawed at 37 °C and diluted either with autologous plasma or 0.9% NaCl. The volume and residual numbers of leukocytes and platelets were tested in both before-freezing and post-thawing periods. Aggregation and thrombin generation tests were used to analyze the in vitro hemostatic functions of platelets. Flow-cytometric analysis was used to assess the presence of frozen treated platelets and their viability. Results: The residual number of leukocytes in both dilution groups was <1x106. The mean platelet recovery rate in the plasma-diluted group (88.1±9.5%) was higher than that in the 0.9% NaCl-diluted group (63±10%). These results were compatible with the European Directorate for the Quality of Medicines quality criteria. Expectedly, there was no aggregation response to platelet aggregation test. The mean thrombin generation potential of post-thaw APCs was higher in the plasma-diluted group (2411 nmol/L per minute) when compared to both the 0.9% NaCl-diluted group (1913 nmol/L per minute) and the before-freezing period (1681 nmol/L per minute). The flow-cytometric analysis results for the viability of APCs after cryopreservation were 94.9% and 96.6% in the plasma and 0.9% NaCl groups, respectively. Conclusion: Cryopreservation of platelets with 6% DMSO and storage at -80 °C increases their shelf life from 7 days to 2 years. Besides the increase in hemostatic functions of platelets, the cryopreservation process also does not affect their viability

  6. Protocol to cryopreserve and isolate nuclei from adipose tissue without dimethyl sulfoxide.

    PubMed

    Almeida, M M; Caires, L C J; Musso, C M; Campos, J M S; Maranduba, C M C; Macedo, G C; Mendonça, J P R F; Garcia, R M G

    2014-01-01

    Cryopreservation injuries involve nuclear DNA damage. A protocol for cryopreserving and isolating adipocyte nuclei is proposed. Adipose tissue samples were directly analyzed (NoCRYO-0h), or stored at -196°C for 7 days without 10% dimethyl sulfoxide (DMSO) (CRYO-WO-DMSO) or with DMSO (CRYO-W-DMSO). To determine the effect of DMSO on cryopreservation treatment, adipose tissue samples were stored at 4°C for 24 h with 10% DMSO (NoCRYO-W-DMSO-24h) and without (NoCRYO-WO-DMSO-24h). Samples were processed in isolation buffer, and nuclear integrity was measured by flow cytometry. The coefficient of variation, forward scatter, side scatter, and number of nuclei analyzed were evaluated. Pea (Pisum sativum) was used to measure the amount of DNA. All groups contained similar amounts of DNA to previously reported values and a satisfactory number of nuclei were analyzed. CRYO-W-DMSO presented a higher coefficient of variation (3.19 ± 0.09) compared to NoCRYO-0h (1.85 ± 0.09) and CRYO-WO-DMSO (2.02 ± 0.02). The coefficient of variation was increased in NoCRYO-W-DMSO-24h (3.80 ± 0.01) compared to NoCRYO-WO-DMSO-24h (2.46 ± 0.03). These results relate DMSO presence to DNA damage independently of the cryopreservation process. CRYO-W-DMSO showed increased side scatter (93.46 ± 5.03) compared to NoCRYO-0h (41.13 ± 3.19) and CRYO-WO-DMSO (48.01 ± 2.28), indicating that cryopreservation with DMSO caused chromatin condensation and/or nuclear fragmentation. CRYO-W-DMSO and CRYO-WO-DMSO presented lower forward scatter (186.33 ± 9.33 and 196.89 ± 26.86, respectively) compared to NoCRYO-0h (322.80 ± 3.36), indicating that cryopreservation reduced nuclei size. Thus, a simple method for cryopreservation and isolation of adipocyte nuclei causing less damage to DNA integrity was proposed. PMID:25526213

  7. Dimethyl sulfoxide inhibits zymosan-induced intestinal inflammation and barrier dysfunction

    PubMed Central

    Li, Yu-Meng; Wang, Hai-Bin; Zheng, Jin-Guang; Bai, Xiao-Dong; Zhao, Zeng-Kai; Li, Jing-Yuan; Hu, Sen

    2015-01-01

    AIM: To investigate whether dimethyl sulfoxide (DMSO) inhibits gut inflammation and barrier dysfunction following zymosan-induced systemic inflammatory response syndrome and multiple organ dysfunction syndrome. METHODS: Sprague-Dawley rats were randomly divided into four groups: sham with administration of normal saline (SS group); sham with administration of DMSO (SD group); zymosan with administration of normal saline (ZS group); and zymosan with administration of DMSO (ZD group). Each group contained three subgroups according to 4 h, 8 h, and 24 h after surgery. At 4 h, 8 h, and 24 h after intraperitoneal injection of zymosan (750 mg/kg), the levels of intestinal inflammatory cytokines [tumor necrosis factor-alpha (TNF-α) and interleukin (IL)-10] and oxides (myeloperoxidase, malonaldehyde, and superoxide dismutase) were examined. The levels of diamine oxidase (DAO) in plasma and intestinal mucosal blood flow (IMBF) were determined. Intestinal injury was also evaluated using an intestinal histological score and apoptosis of intestinal epithelial cells was determined by deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay. The intestinal epithelial tight junction protein, ZO-1, was observed by immunofluorescence. RESULTS: DMSO decreased TNF-α and increased IL-10 levels in the intestine compared with the ZS group at the corresponding time points. The activity of intestinal myeloperoxidase in the ZS group was higher than that in the ZD group 24 h after zymosan administration (P < 0.05). DMSO decreased the content of malondialdehyde (MDA) and increased the activity of superoxide dehydrogenase (SOD) 24 h after zymosan administration. The IMBF was lowest at 24 h and was 49.34% and 58.26% in the ZS group and ZD group, respectively (P < 0.05). DMSO alleviated injury in intestinal villi, and the gut injury score was significantly lower than the ZS group (3.6 ± 0.2 vs 4.2 ± 0.3, P < 0.05). DMSO decreased the level of DAO in plasma compared with the ZS

  8. Fluorine-18 radiolabeling of a nitrophenyl sulfoxide and its evaluation in an SK-RC-52 model of tumor hypoxia.

    PubMed

    Laurens, Evelyn; Yeoh, Shinn Dee; Rigopoulos, Angela; O'Keefe, Graeme J; Tochon-Danguy, Henri J; Chong, Lee Wenn; White, Jonathan M; Scott, Andrew M; Ackermann, Uwe

    2016-08-01

    The significance of imaging hypoxia with the positron emission tomography ligand [(18) F]FMISO has been demonstrated in a variety of cancers. However, the slow kinetics of [(18) F]FMISO require a 2-h delay between tracer administration and patient scanning. Labeled chloroethyl sulfoxides have shown faster kinetics and higher contrast than [(18) F]FMISO in a rat model of ischemic stroke. However, these nitrogen mustard analogues are unsuitable for routine production and use in humans. Here, we report on the synthesis and in vitro and in vivo evaluation of a novel sulfoxide, which contains an ester moiety for hydrolysis and subsequent trapping in hypoxic cells. Non-decay corrected yields of radioactivity were 1.18 ± 0.24% (n = 27, 2.5 ± 0.5% decay corrected radiochemical yield) based on K[(18) F]F. The radiotracer did not show any defluorination and did not undergo metabolism in an in vitro assay using S9 liver fractions. Imaging studies using an SK-RC-52 tumor model in BALB/c nude mice have revealed that [(18) F]1 is retained in hypoxic tumors and has similar hypoxia selectivity to [(18) F]FMISO. Because of a three times faster clearance rate than [(18) F]FMISO from normoxic tissue, [(18) F]1 has emerged as a promising new radiotracer for hypoxia imaging. PMID:27435268

  9. Detection of oxidized methionine in selected proteins, cellular extracts, and blood serums by novel anti-methionine sulfoxide antibodies

    PubMed Central

    Oien, Derek B.; Canello, Tamar; Gabizon, Ruth; Gasset, Maria; Lundquist, Brandi L.; Burns, Jeff M; Moskovitz, Jackob

    2009-01-01

    Methionine sulfoxide (MetO) is a common posttranslational modification to proteins occurring in vivo. These modifications are prevalent when reactive oxygen species levels are increased. To enable the detection of MetO in pure and extracted proteins from various sources, we have developed novel antibodies that can recognize MetO-proteins. These antibodies are polyclonal antibodies raised against an oxidized methionine-rich zein protein (MetO-DZS18) that are shown to recognize methionine oxidation in pure proteins and mouse and yeast extracts. Furthermore, mouse serum albumin and immunoglobulin (IgG) were shown to accumulate MetO as function of age especially in serums of methionine sulfoxide reductase A knockout mice. Interestingly, high levels of methionine-oxidized IgG in serums of subjects diagnosed with Alzheimer’s disease were detected by western blot analysis using these antibodies. It is suggested that anti-MetO-DZS18 antibodies can be applied in the identification of proteins that undergo methionine oxidation under oxidative stress, aging, or disease state conditions. PMID:19388147

  10. Methionine Sulfoxide Reductase B2 is Highly Expressed in the Retina and Protects Retinal Pigmented Epithelium Cells from Oxidative Damage

    PubMed Central

    Pascual, Iranzu; Larrayoz, Ignacio M.; Campos, Maria M.; Rodriguez, Ignacio R.

    2010-01-01

    Methionine sulfoxide reductase B2 (MSRB2) is a mitochondrial enzyme that converts methionine sulfoxide (R) enantiomer back to methionine. This enzyme is suspected of functioning to protect mitochondrial proteins from oxidative damage. In this study we report that the retina is one of the human tissues with highest levels of MSRB2 mRNA expression. Other tissues with high expression were heart, kidney and skeletal muscle. Over-expression of a MSRB2-GFP fusion protein increased the MSR enzymatic activity three-fold in stably transfected cultured RPE cells. This overexpression augmented the resistance of these cells to the toxicity induced by 7-ketocholesterol, tert-butyl hydroperoxide and all-trans retinoic acid. By contrast, knockdown of MSRB2 by a miRNA in stably transfected cells did not convey increased sensitivity to the oxidative stress. In the monkey retina MSRB2 localized to the ganglion cell layer (GLC), the outer plexiform layer (OPL) and the retinal pigment epithelium (RPE). MSRB2 expression is most pronounced in the OPL of the macula and foveal regions suggesting an association with the cone synaptic mitochondria. Our data suggests that MSRB2 plays an important function in protecting cones from multiple type of oxidative stress and may be critical in preserving central vision. PMID:20026324

  11. Influence of ligand and environment substitution on photo-triggered linkage isomerization of photochromic ruthenium sulfoxide complexes

    NASA Astrophysics Data System (ADS)

    Springfeld, Kristin; Dieckmann, Volker; Eicke, Sebastian; Imlau, Mirco

    2012-02-01

    The group of ruthenium polypyridine sulfoxides features a pronounced photochromism in the UV/VIS spectral range based on an ultrafast photo-triggered linkage isomerization located at the SO-ligand. This isomerization exhibits a tremendous photosensitivity and a high thermal stability of the two metastable structural isomers. Here, we discuss the characteristic photochromic properties of the compounds in the frame of ligand substitution and the replacement of the dielectric environment. The complex [Ru(bpy)2(ROSO)].PF6 [1] (with OSO: 2-methylsulfinylbenzoate) has been modified with the groups R = H, Bn, BnCl and BnMe [2] and studied in different solvents as well as in polydimethylsiloxane. The analysis is performed by cw-pump-probe technique as a function of temperature and exposure. Our results reveal a selective adjustability of the thermal stability in the compounds, while the photosensitivity and the characteristic absorption spectra remain unchanged. We discuss the impact of sulfoxide compounds with the desired features in view of application in molecular photonic devices.[4pt] [1] V. Dieckmann et al., Opt. Express 17, 15052 (2009)[2] V. Dieckmann et al., Opt. Express 18, 23495 (2010)

  12. Methionine sulfoxide reductase A (MsrA) contributes to Salmonella Typhimurium survival against oxidative attack of neutrophils.

    PubMed

    Trivedi, Raj Narayan; Agarwal, Pranjali; Kumawat, Manoj; Pesingi, Pavan Kumar; Gupta, Vivek Kumar; Goswami, Tapas Kumar; Mahawar, Manish

    2015-12-01

    Salmonella Typhimurium (ST) must evade neutrophil assault for infection establishment in the host. Myeloperoxidase generated HOCl is the key antimicrobial agent produced by the neutrophils; and methionine (Met) residues are the primary targets of this oxidant. Oxidation of Mets leads to methionine sulfoxide (Met-SO) formation and consequently compromises the protein function(s). Methionine sulfoxide reductase A (MsrA) reductively repairs Met-SO to Mets. In this manner, MsrA maintains the function(s) of key proteins which are important for virulence of ST and enhance the survival of this bacterium under oxidative stress. We constructed msrA gene deletion strain (ΔmsrA). The primers located in the flanking regions to ΔmsrA gene amplified 850 and 300 bp amplicons in ST and ΔmsrA strains, respectively. The ΔmsrA strain grew normally in in vitro broth culture. However, ΔmsrA strain showed high susceptibility (p<0.001) to very low concentrations of HOCl which was restored (at least in part) by plasmid based complementation. ΔmsrA strain was hypersensitive (than ST) to the granules isolated from neutrophils. Further, the ΔmsrA strain was significantly (p<0.05) more susceptible to neutrophil mediated killing. PMID:26224245

  13. Corynebacterium glutamicum methionine sulfoxide reductase A uses both mycoredoxin and thioredoxin for regeneration and oxidative stress resistance.

    PubMed

    Si, Meiru; Zhang, Lei; Chaudhry, Muhammad Tausif; Ding, Wei; Xu, Yixiang; Chen, Can; Akbar, Ali; Shen, Xihui; Liu, Shuang-Jiang

    2015-04-01

    Oxidation of methionine leads to the formation of the S and R diastereomers of methionine sulfoxide (MetO), which can be reversed by the actions of two structurally unrelated classes of methionine sulfoxide reductase (Msr), MsrA and MsrB, respectively. Although MsrAs have long been demonstrated in numerous bacteria, their physiological and biochemical functions remain largely unknown in Actinomycetes. Here, we report that a Corynebacterium glutamicum methionine sulfoxide reductase A (CgMsrA) that belongs to the 3-Cys family of MsrAs plays important roles in oxidative stress resistance. Deletion of the msrA gene in C. glutamicum resulted in decrease of cell viability, increase of ROS production, and increase of protein carbonylation levels under various stress conditions. The physiological roles of CgMsrA in resistance to oxidative stresses were corroborated by its induced expression under various stresses, regulated directly by the stress-responsive extracytoplasmic-function (ECF) sigma factor SigH. Activity assays performed with various regeneration pathways showed that CgMsrA can reduce MetO via both the thioredoxin/thioredoxin reductase (Trx/TrxR) and mycoredoxin 1/mycothione reductase/mycothiol (Mrx1/Mtr/MSH) pathways. Site-directed mutagenesis confirmed that Cys56 is the peroxidatic cysteine that is oxidized to sulfenic acid, while Cys204 and Cys213 are the resolving Cys residues that form an intramolecular disulfide bond. Mrx1 reduces the sulfenic acid intermediate via the formation of an S-mycothiolated MsrA intermediate (MsrA-SSM) which is then recycled by mycoredoxin and the second molecule of mycothiol, similarly to the glutathione/glutaredoxin/glutathione reductase (GSH/Grx/GR) system. However, Trx reduces the Cys204-Cys213 disulfide bond in CgMsrA produced during MetO reduction via the formation of a transient intermolecular disulfide bond between Trx and CgMsrA. While both the Trx/TrxR and Mrx1/Mtr/MSH pathways are operative in reducing CgMsrA under

  14. Novel mechanism for scavenging of hypochlorite involving a periplasmic methionine-rich peptide and methionine sulfoxide reductase

    DOE PAGESBeta

    Melnyk, Ryan A.; Youngblut, Matthew D.; Clark, Iain C.; Carlson, Hans K.; Wetmore, Kelly M.; Price, Morgan N.; Lavarone, Anthony T.; Deutschbauer, Adam M.; Arkin, Adam P.; Coates, John D.

    2015-05-12

    Reactive chlorine species (RCS) defense mechanisms are important for bacterial fitness in diverse environments. In addition to the anthropogenic use of RCS in the form of bleach, these compounds are also produced naturally through photochemical reactions of natural organic matter and in vivo by the mammalian immune system in response to invading microorganisms. To gain insight into bacterial RCS defense mechanisms, we investigated Azospira suillum strain PS, which produces periplasmic RCS as an intermediate of perchlorate respiration. Our studies identified an RCS response involving an RCS stress-sensing sigma/anti-sigma factor system (SigF/NrsF), a soluble hypochlorite-scavenging methionine-rich periplasmic protein (MrpX), and amore » putative periplasmic methionine sulfoxide reductase (YedY1). We investigated the underlying mechanism by phenotypic characterization of appropriate gene deletions, chemogenomic profiling of barcoded transposon pools, transcriptome sequencing, and biochemical assessment of methionine oxidation. Our results demonstrated that SigF was specifically activated by RCS and initiated the transcription of a small regulon centering around yedY1 and mrpX. A yedY1 paralog (yedY2) was found to have a similar fitness to yedY1 despite not being regulated by SigF. Markerless deletions of yedY2 confirmed its synergy with the SigF regulon. MrpX was strongly induced and rapidly oxidized by RCS, especially hypochlorite. Our results suggest a mechanism involving hypochlorite scavenging by sacrificial oxidation of the MrpX in the periplasm. Reduced MrpX is regenerated by the YedY methionine sulfoxide reductase activity. The phylogenomic distribution of this system revealed conservation in several Proteobacteria of clinical importance, including uropathogenic Escherichia coli and Brucella spp., implying a putative role in immune response evasion in vivo. In addition, bacteria are often stressed in the environment by reactive chlorine species (RCS) of

  15. Novel mechanism for scavenging of hypochlorite involving a periplasmic methionine-rich peptide and methionine sulfoxide reductase

    SciTech Connect

    Melnyk, Ryan A.; Youngblut, Matthew D.; Clark, Iain C.; Carlson, Hans K.; Wetmore, Kelly M.; Price, Morgan N.; Lavarone, Anthony T.; Deutschbauer, Adam M.; Arkin, Adam P.; Coates, John D.

    2015-05-12

    Reactive chlorine species (RCS) defense mechanisms are important for bacterial fitness in diverse environments. In addition to the anthropogenic use of RCS in the form of bleach, these compounds are also produced naturally through photochemical reactions of natural organic matter and in vivo by the mammalian immune system in response to invading microorganisms. To gain insight into bacterial RCS defense mechanisms, we investigated Azospira suillum strain PS, which produces periplasmic RCS as an intermediate of perchlorate respiration. Our studies identified an RCS response involving an RCS stress-sensing sigma/anti-sigma factor system (SigF/NrsF), a soluble hypochlorite-scavenging methionine-rich periplasmic protein (MrpX), and a putative periplasmic methionine sulfoxide reductase (YedY1). We investigated the underlying mechanism by phenotypic characterization of appropriate gene deletions, chemogenomic profiling of barcoded transposon pools, transcriptome sequencing, and biochemical assessment of methionine oxidation. Our results demonstrated that SigF was specifically activated by RCS and initiated the transcription of a small regulon centering around yedY1 and mrpX. A yedY1 paralog (yedY2) was found to have a similar fitness to yedY1 despite not being regulated by SigF. Markerless deletions of yedY2 confirmed its synergy with the SigF regulon. MrpX was strongly induced and rapidly oxidized by RCS, especially hypochlorite. Our results suggest a mechanism involving hypochlorite scavenging by sacrificial oxidation of the MrpX in the periplasm. Reduced MrpX is regenerated by the YedY methionine sulfoxide reductase activity. The phylogenomic distribution of this system revealed conservation in several Proteobacteria of clinical importance, including uropathogenic Escherichia coli and Brucella spp., implying a putative role in immune response evasion in vivo. In addition, bacteria are often

  16. Developing an Acidic Residue Reactive and Sulfoxide-Containing MS-Cleavable Homobifunctional Cross-Linker for Probing Protein-Protein Interactions.

    PubMed

    Gutierrez, Craig B; Yu, Clinton; Novitsky, Eric J; Huszagh, Alexander S; Rychnovsky, Scott D; Huang, Lan

    2016-08-16

    Cross-linking mass spectrometry (XL-MS) has become a powerful strategy for defining protein-protein interactions and elucidating architectures of large protein complexes. However, one of the inherent challenges in MS analysis of cross-linked peptides is their unambiguous identification. To facilitate this process, we have previously developed a series of amine-reactive sulfoxide-containing MS-cleavable cross-linkers. These MS-cleavable reagents have allowed us to establish a common robust XL-MS workflow that enables fast and accurate identification of cross-linked peptides using multistage tandem mass spectrometry (MS(n)). Although amine-reactive reagents targeting lysine residues have been successful, it remains difficult to characterize protein interaction interfaces with little or no lysine residues. To expand the coverage of protein interaction regions, we present here the development of a new acidic residue-targeting sulfoxide-containing MS-cleavable homobifunctional cross-linker, dihydrazide sulfoxide (DHSO). We demonstrate that DHSO cross-linked peptides display the same predictable and characteristic fragmentation pattern during collision induced dissociation as amine-reactive sulfoxide-containing MS-cleavable cross-linked peptides, thus permitting their simplified analysis and unambiguous identification by MS(n). Additionally, we show that DHSO can provide complementary data to amine-reactive reagents. Collectively, this work not only enlarges the range of the application of XL-MS approaches but also further demonstrates the robustness and applicability of sulfoxide-based MS-cleavability in conjunction with various cross-linking chemistries. PMID:27417384

  17. Developing an Acidic Residue Reactive and Sulfoxide-Containing MS-Cleavable Homobifunctional Cross-Linker for Probing Protein–Protein Interactions

    PubMed Central

    2016-01-01

    Cross-linking mass spectrometry (XL-MS) has become a powerful strategy for defining protein–protein interactions and elucidating architectures of large protein complexes. However, one of the inherent challenges in MS analysis of cross-linked peptides is their unambiguous identification. To facilitate this process, we have previously developed a series of amine-reactive sulfoxide-containing MS-cleavable cross-linkers. These MS-cleavable reagents have allowed us to establish a common robust XL-MS workflow that enables fast and accurate identification of cross-linked peptides using multistage tandem mass spectrometry (MSn). Although amine-reactive reagents targeting lysine residues have been successful, it remains difficult to characterize protein interaction interfaces with little or no lysine residues. To expand the coverage of protein interaction regions, we present here the development of a new acidic residue-targeting sulfoxide-containing MS-cleavable homobifunctional cross-linker, dihydrazide sulfoxide (DHSO). We demonstrate that DHSO cross-linked peptides display the same predictable and characteristic fragmentation pattern during collision induced dissociation as amine-reactive sulfoxide-containing MS-cleavable cross-linked peptides, thus permitting their simplified analysis and unambiguous identification by MSn. Additionally, we show that DHSO can provide complementary data to amine-reactive reagents. Collectively, this work not only enlarges the range of the application of XL-MS approaches but also further demonstrates the robustness and applicability of sulfoxide-based MS-cleavability in conjunction with various cross-linking chemistries. PMID:27417384

  18. Modification of electrical properties of PEDOT:PSS/p-Si heterojunction diodes by doping with dimethyl sulfoxide

    NASA Astrophysics Data System (ADS)

    Pathak, C. S.; Singh, J. P.; Singh, R.

    2016-05-01

    We report about the fabrication and electrical characterization of heterojunction diodes between poly (3,4-ethylenedioxythiophene) poly(styrenesulfonate) (PEDOT:PSS) doped with dimethyl sulfoxide (DMSO) and p-Si. Electrical characterization of the heterojunction diodes was performed using current-voltage (I-V) measurements. The heterojunction diodes showed good rectifying behavior. Interestingly, for 5 vol.% doping concentration of DMSO, the heterojunction diode showed the best diode characteristics with an ideality factor of 1.9. The doping of DMSO into PEDOT:PSS solution resulted in an increase in the conductivity of films by two orders of magnitude and the films showed high optical transmission (>85%) in the visible region.

  19. Dipolar Self-Assembling in Mixtures of Propylene Carbonate and Dimethyl Sulfoxide as Revealed by the Orientational Entropy.

    PubMed

    Płowaś, Iwona; Świergiel, Jolanta; Jadżyn, Jan

    2016-08-18

    This article presents the results of static dielectric studies performed on mixtures of two strongly polar liquids important from a technological point of view: propylene carbonate (PC) and dimethyl sulfoxide (DMSO). The dielectric data were analyzed in terms of the molar orientational entropy increment induced by the probing electric field. It was found that the two polar liquids in the neat state reveal quite different molecular organization in terms of dipole-dipole self-assembling: PC exhibits a dipolar coupling of the head-to-tail type, whereas in DMSO one observes extreme restriction of dipolar association in any form. In PC + DMSO mixtures, the disintegration of the dipolar ensembles of PC molecules takes place and the progress of that process is strictly proportional to the concentration of DMSO. The static permittivity of mixtures of such differently self-organized liquids exhibits a positive deviation from the additive rule and the deviation develops symmetrically within the concentration scale. PMID:27458791

  20. High cell density cultivation of Pseudomonas putida strain HKT554 and its application for optically active sulfoxide production.

    PubMed

    Ramadhan, Said Hamad; Matsui, Toru; Nakano, Kazuma; Minami, Hirofumi

    2013-03-01

    Culture conditions with Pseudomonas putida strain HKT554, expressing naphthalene dioxygenase, known as the biocatalyst showing wide substrate specificity, were optimized for high cell density cultivation (HCDC). Culture in a medium TK-B modified from that for HCDC of Escherichia coli with glucose fed-batch and dissolved oxygen stat resulted in a high cell density growth of 114 g dry cell/l at 40 h of cultivation. This system was further applied for S-(+)-methyl phenyl sulfoxide (MPSO) production from methyl phenyl sulfide. Addition of nonpolar organic solvent, such as n-hexadecane, greatly enhanced the MPSO production due to the prevention of substrate evaporation, resulting in a MPSO production up to 39 mM in 30 h with a conversion rate of 95.7 mol%. PMID:23053095

  1. Bovine serum albumin-cobalt(ii) Schiff base complex hybrid: an efficient artificial metalloenzyme for enantioselective sulfoxidation using hydrogen peroxide.

    PubMed

    Tang, Jie; Huang, Fuping; Wei, Yi; Bian, Hedong; Zhang, Wei; Liang, Hong

    2016-05-10

    An artificial metalloenzyme (BSA-CoL) based on the incorporation of a cobalt(ii) Schiff base complex {CoL, H2L = 2,2'-[(1,2-ethanediyl)bis(nitrilopropylidyne)]bisphenol} with bovine serum albumin (BSA) has been synthesized and characterized. Attention is focused on the catalytic activity of this artificial metalloenzyme for enantioselective oxidation of a variety of sulfides with H2O2. The influences of parameters such as pH, temperature, and the concentration of catalyst and oxidant on thioanisole as a model are investigated. Under optimum conditions, BSA-CoL as a hybrid biocatalyst is efficient for the enantioselective oxidation of a series of sulfides, producing the corresponding sulfoxides with excellent conversion (up to 100%), chemoselectivity (up to 100%) and good enantiomeric purity (up to 87% ee) in certain cases. PMID:27075699

  2. Importance of Reaction Kinetics and Oxygen Crossover in aprotic Li-O2 Batteries Based on a Dimethyl Sulfoxide Electrolyte.

    PubMed

    Marinaro, M; Balasubramanian, P; Gucciardi, E; Theil, S; Jörissen, L; Wohlfahrt-Mehrens, M

    2015-09-21

    Although still in their embryonic state, aprotic rechargeable Li-O2 batteries have, theoretically, the capabilities of reaching higher specific energy densities than Li-ion batteries. There are, however, significant drawbacks that must be addressed to allow stable electrochemical performance; these will ultimately be solved by a deeper understanding of the chemical and electrochemical processes occurring during battery operations. We report a study on the electrochemical and chemical stability of Li-O2 batteries comprising Au-coated carbon cathodes, a dimethyl sulfoxide (DMSO)-based electrolyte and Li metal negative electrodes. The use of the aforementioned Au-coated cathodes in combination with a 1 M lithium bis(trifluoromethane)sulfonimide (LiTFSI)-DMSO electrolyte guarantees very good cycling stability (>300 cycles) by minimizing eventual side reactions. The main drawbacks arise from the high reactivity of the Li metal electrode when in contact with the O2 -saturated DMSO-based electrolyte. PMID:26249807

  3. Effect of dimethyl sulfoxide on ionic liquid 1-ethyl-3-methylimidazolium acetate pretreatment of eucalyptus wood for enzymatic hydrolysis.

    PubMed

    Wu, Long; Lee, Seung-Hwan; Endo, Takashi

    2013-07-01

    Ground eucalyptus wood was pretreated with 1-ethyl-3-methylimidazolium acetate ([EMIM]OAc)-dimethyl sulfoxide (DMSO) solutions with different mixing ratios under various conditions. The changes in the composition and structure of the biomass were investigated; and the enzymatic hydrolysis performance of the pretreated biomass was evaluated. [EMIM]OAc-DMSO pretreatment had a relatively mild effect on the composition of the biomass, but excessively high pretreatment temperatures led to massive loss of xylan after pretreatment. The enzymatic digestibility of the biomass was significantly improved with increased pretreatment temperature. X-ray diffraction analysis revealed that the disruption of cellulose crystal structure by [EMIM]OAc at a sufficiently high temperature was primarily responsible for the remarkable improvement in the digestibility. Appropriate addition of DMSO could help minimize the consumption of [EMIM]OAc without impairing the performance of the ionic liquid, and contribute to the improvement in pretreatment efficiency due to the viscosity reduction effect on the pretreatment liquor. PMID:23685645

  4. Stereospecific capillary electrophoresis assays using pentapeptide substrates for the study of Aspergillus nidulans methionine sulfoxide reductase A and mutant enzymes.

    PubMed

    Zhu, Qingfu; El-Mergawy, Rabab G; Zhou, Yuzhen; Chen, Chunyang; Heinemann, Stefan H; Schönherr, Roland; Robaa, Dina; Sippl, Wolfgang; Scriba, Gerhard K E

    2016-07-01

    Stereospecific capillary electrophoresis-based methods for the analysis of methionine sulfoxide [Met(O)]-containing pentapeptides were developed in order to investigate the reduction of Met(O)-containing peptide substrates by recombinant Aspergillus nidulans methionine sulfoxide reductase A (MsrA) as well as enzymes carrying mutations in position Glu99 and Asp134. The separation of the diastereomers of the N-acetylated, C-terminally 2,4-dinitrophenyl (Dnp)-labeled pentapeptides ac-Lys-Phe-Met(O)-Lys-Lys-Dnp, ac-Lys-Asp-Met(O)-Asn-Lys-Dnp and ac-Lys-Asn-Met(O)-Asp-Lys-Dnp was achieved in 50 mM Tris-HCl buffers containing sulfated β-CD in fused-silica capillaries, while the diastereomer separation of ac-Lys-Asp-Met(O)-Asp-Lys-Dnp was achieved by sulfated β-CD-mediated MEKC. The methods were validated with regard to range, linearity, accuracy, limits of detection and quantitation as well as precision. Subsequently, the substrates were incubated with wild-type MsrA and three mutants in the presence of dithiothreitol as reductant. Wild-type MsrA displayed the highest activity towards all substrates compared to the mutants. Substitution of Glu99 by Gln resulted in the mutant with the lowest activity towards all substrates except for ac-Lys-Asn-Met(O)-Asp-Lys-Dnp, while replacement Asn for Asp134 lead to a higher activity towards ac-Lys-Asp-Met(O)-Asn-Lys-Dnp compared with the Glu99 mutant. The mutant with Glu instead of Asp134 was the most active among the mutant enzymes. Molecular modeling indicated that the conserved Glu99 residue is buried in the Met-S-(O) groove, which might contribute to the correct placing of substrates and, consequently, to the catalytic activity of MsrA, while Asp134 did not form hydrogen bonds with the substrates but only within the enzyme. PMID:27145186

  5. Plant Thioredoxin CDSP32 Regenerates 1-Cys Methionine Sulfoxide Reductase B Activity through the Direct Reduction of Sulfenic Acid*

    PubMed Central

    Tarrago, Lionel; Laugier, Edith; Zaffagnini, Mirko; Marchand, Christophe H.; Le Maréchal, Pierre; Lemaire, Stéphane D.; Rey, Pascal

    2010-01-01

    Thioredoxins (Trxs) are ubiquitous enzymes catalyzing the reduction of disulfide bonds, thanks to a CXXC active site. Among their substrates, 2-Cys methionine sulfoxide reductases B (2-Cys MSRBs) reduce the R diastereoisomer of methionine sulfoxide (MetSO) and possess two redox-active Cys as follows: a catalytic Cys reducing MetSO and a resolving one, involved in disulfide bridge formation. The other MSRB type, 1-Cys MSRBs, possesses only the catalytic Cys, and their regeneration mechanisms by Trxs remain unclear. The plant plastidial Trx CDSP32 is able to provide 1-Cys MSRB with electrons. CDSP32 includes two Trx modules with one potential active site 219CGPC222 and three extra Cys. Here, we investigated the redox properties of recombinant Arabidopsis CDSP32 and delineated the biochemical mechanisms of MSRB regeneration by CDSP32. Free thiol titration and 4-acetamido-4′-maleimidyldistilbene-2,2′-disulfonic acid alkylation assays indicated that the Trx possesses only two redox-active Cys, very likely the Cys219 and Cys222. Protein electrophoresis analyses coupled to mass spectrometry revealed that CDSP32 forms a heterodimeric complex with MSRB1 via reduction of the sulfenic acid formed on MSRB1 catalytic Cys after MetSO reduction. MSR activity assays using variable CDSP32 amounts revealed that MSRB1 reduction proceeds with a 1:1 stoichiometry, and redox titrations indicated that CDSP32 and MSRB1 possess midpoints potentials of −337 and −328 mV at pH 7.9, respectively, indicating that regeneration of MSRB1 activity by the Trx through sulfenic acid reduction is thermodynamically feasible in physiological conditions. PMID:20236937

  6. Novel Mechanism for Scavenging of Hypochlorite Involving a Periplasmic Methionine-Rich Peptide and Methionine Sulfoxide Reductase

    PubMed Central

    Melnyk, Ryan A.; Youngblut, Matthew D.; Clark, Iain C.; Carlson, Hans K.; Wetmore, Kelly M.; Price, Morgan N.; Iavarone, Anthony T.; Deutschbauer, Adam M.; Arkin, Adam P.

    2015-01-01

    ABSTRACT Reactive chlorine species (RCS) defense mechanisms are important for bacterial fitness in diverse environments. In addition to the anthropogenic use of RCS in the form of bleach, these compounds are also produced naturally through photochemical reactions of natural organic matter and in vivo by the mammalian immune system in response to invading microorganisms. To gain insight into bacterial RCS defense mechanisms, we investigated Azospira suillum strain PS, which produces periplasmic RCS as an intermediate of perchlorate respiration. Our studies identified an RCS response involving an RCS stress-sensing sigma/anti-sigma factor system (SigF/NrsF), a soluble hypochlorite-scavenging methionine-rich periplasmic protein (MrpX), and a putative periplasmic methionine sulfoxide reductase (YedY1). We investigated the underlying mechanism by phenotypic characterization of appropriate gene deletions, chemogenomic profiling of barcoded transposon pools, transcriptome sequencing, and biochemical assessment of methionine oxidation. Our results demonstrated that SigF was specifically activated by RCS and initiated the transcription of a small regulon centering around yedY1 and mrpX. A yedY1 paralog (yedY2) was found to have a similar fitness to yedY1 despite not being regulated by SigF. Markerless deletions of yedY2 confirmed its synergy with the SigF regulon. MrpX was strongly induced and rapidly oxidized by RCS, especially hypochlorite. Our results suggest a mechanism involving hypochlorite scavenging by sacrificial oxidation of the MrpX in the periplasm. Reduced MrpX is regenerated by the YedY methionine sulfoxide reductase activity. The phylogenomic distribution of this system revealed conservation in several Proteobacteria of clinical importance, including uropathogenic Escherichia coli and Brucella spp., implying a putative role in immune response evasion in vivo. PMID:25968643

  7. Depression of the ice-nucleation temperature of rapidly cooled mouse embryos by glycerol and dimethyl sulfoxide.

    PubMed Central

    Rall, W F; Mazur, P; McGrath, J J

    1983-01-01

    The temperature at which ice formation occurs in supercooled cytoplasm is an important element in predicting the likelihood of intracellular freezing of cells cooled by various procedures to subzero temperatures. We have confirmed and extended prior indications that permeating cryoprotective additives decrease the ice nucleation temperature of cells, and have determined some possible mechanisms for the decrease. Our experiments were carried out on eight-cell mouse embryos equilibrated with various concentrations (0-2.0 M) of dimethyl sulfoxide or glycerol and then cooled rapidly. Two methods were used to assess the nucleation temperature. The first, indirect, method was to determine the in vitro survival of the rapidly cooled embryos as a function of temperature. The temperatures over which an abrupt drop in survival occurs are generally diagnostic of the temperature range for intracellular freezing. The second, direct, method was to observe the microscopic appearance during rapid cooling and note the temperature at which nucleation occurred. Both methods showed that the nucleation temperature decreased from - 10 to - 15 degrees C in saline alone to between - 38 degrees and - 44 degrees C in 1.0-2.0 M glycerol and dimethyl sulfoxide. The latter two temperatures are close to the homogeneous nucleation temperatures of the solutions in the embryo cytoplasm, and suggest that embryos equilibrated in these solutions do not contain heterogeneous nucleating agents and are not accessible to any extracellular nucleating agents, such as extracellular ice. The much higher freezing temperatures of cells in saline or in low concentrations of additive indicate that they are being nucleated by heterogeneous agents or, more likely, by extracellular ice. Images FIGURE 5 FIGURE 6 PMID:6824748

  8. 6-(2-Chloro­benzyl­amino)purinium tetra­chlorido(dimethyl sulfoxide-κO)(nitrosyl-κN)ruthenate(III) monohydrate

    PubMed Central

    Trávníček, Zdeněk; Matiková-Maľarová, Miroslava; Štěpánková, Kamila

    2008-01-01

    The asymmetric unit of the title complex salt, (C12H11ClN5)[RuCl4(NO)(C2H6OS)]·H2O, contains a 6-(2-chloro­benzyl­amino)purinium cation, a tetra­chlorido(dimethyl sulfoxide)nitro­sylruthenate(III) anion and one solvent water mol­ecule. The RuIII atom is octa­hedrally coordinated by four Cl atoms in the equatorial plane, and by a dimethyl sulfoxide O atom and a nitrosyl N atom in axial positions. The cation is an N3-protonated N7 tautomer. Inter­molecular N–H⋯N hydrogen bonds connect two cations into centrosymmetric dimers, with an N⋯N distance of 2.821 (4) Å. The crystal structure also involves N—H⋯O, N—H⋯Cl and O—H⋯Cl hydrogen bonds. PMID:21202003

  9. Gene overexpression, purification, and identification of a desulfurization enzyme from Rhodococcus sp. strain IGTS8 as a sulfide/sulfoxide monooxygenase.

    PubMed Central

    Lei, B; Tu, S C

    1996-01-01

    The oxidation of dibenzothiophene to dibenzothiophene sulfone has been linked to the enzyme encoded by the sox/dszC gene from Rhodococcus sp. strain IGTS8 (S. A. Denome, C. Oldfield, L. J. Nash, and K. D. Young, J. Bacteriol. 176:6707-6717, 1994; C. S. Piddington, B. R. Kovacevich, and J. Rambosek, Appl. Environ. Microbiol. 61:468-475, 1995). However, this enzyme has not been characterized, and the type of its catalytic activity remains unclassified. In this work, the sox/dszC gene was overexpressed in Escherichia coli, a procedure for the purification of the expressed enzyme was developed, and the properties of and the reactions catalyzed by the purified enzyme were characterized. This enzyme binds one flavin mononucleotide (Kd, 7 micrometers) or reduced flavin mononucleotide (FMNH2) (Kd < 10(-8) M) per 90,200-Da homodimer, and FMNH2 is an essential cosubstrate for its activity. Patterns of product formation were examined under different FMNH2 availabilities, and results indicate that this enzyme catalyzes a stepwise conversion of dibenzothiophene to the corresponding sulfoxide and subsequently to the sulfone. On the basis of isotope labeling patterns with H2(18)O and 18O2, dibenzothiophene sulfoxide and sulfone obtained their oxygen atom(s) from molecular oxygen rather than water in their formation from dibenzothiophene. The enzyme also utilizes benzyl sulfide and benzyl sulfoxide as substrates. Hence, it is identified as a sulfide/sulfoxide monooxygenase. This monooxygenase is similar to the microsomal flavin-containing monooxygenase but is unique among microbial flavomonooxygenases in its ability to catalyze two consecutive monooxygenation reactions. PMID:8824615

  10. N-acetyl-5-N,4-O-oxazolidinone-protected sialyl sulfoxide: an α-selective sialyl donor with Tf2O/(Tol)2SO in dichloromethane.

    PubMed

    Gu, Zhen-yuan; Zhang, Jia-xin; Xing, Guo-wen

    2012-06-01

    Sweet as sugar: Sialyl sulfoxide protected by N-acetyl-5-N,4-O-oxazolidinone was readily prepared, and its coupling to various sugar acceptors was investigated. When the reaction was promoted by Tf(2)O/(Tol)(2)SO, efficient and highly α-selective sialylation yielded α(2,6), α(2,3), and α(2,4) glycosidic linkages between sialic acid and glucose/glacotose. PMID:22488903

  11. Poly[di-μ2-chlorido-dichlorido(μ3-di­methyl sulfoxide-κ3 O:O:S)(μ2-di­methyl sulfoxide-κ2 O:S)ruthenium(III)sodium

    PubMed Central

    Trávníček, Zdeněk; Matiková-Maľarová, Miroslava

    2010-01-01

    The structure of the title compound, [NaRuCl4(C2H6OS)2]n, comprises centrosymmetric [RuCl2(DMSO)Na(DMSO)Cl2Ru] units (DMSO is dimethyl sulfoxide, C2H6OS), with two Ru atoms, each lying on a crystallographic centre of inversion, connected via Na atoms, DMSO and chloride ligands into a two-dimensional (110) array. Both RuIII atoms are octa­hedrally coordinated by four chloride ligands in the equatorial plane and by two DMSO mol­ecules in apical positions within a RuCl4S2 donor set. The Na atom is surrounded by three chloride anions and three O atoms derived from three DMSO mol­ecules, with the resulting Cl3O3 donor set defining an octa­hedron. The crystal structure is further stabilized by inter­atomic inter­actions of the types C⋯Cl [C—Cl = 3.284 (2) Å], C—H⋯Cl [C⋯Cl = 3.903 (3) Å] and C—H⋯O [C⋯O = 3.376 (3) Å]. PMID:21580464

  12. Synthesis Of [2h, 13c]M [2h2m 13c], And [2h3,, 13c] Methyl Aryl Sulfones And Sulfoxides

    DOEpatents

    Martinez, Rodolfo A.; Alvarez, Marc A.; Silks, III, Louis A.; Unkefer, Clifford J.; Schmidt, Jurgen G.

    2004-07-20

    The present invention is directed to labeled compounds, [.sup.2 H.sub.1, .sup.13 C], [.sup.2 H.sub.2, .sup.13 C] and [.sup.2 H.sub.3, .sup.13 C]methyl aryl sulfones and [.sup.2 H.sub.1, .sup.13 C], [.sup.2 H.sub.2, .sup.13 C] and [.sup.2 H.sub.3, .sup.13 C]methyl aryl sulfoxides, wherein the .sup.13 C methyl group attached to the sulfur of the sulfone or sulfoxide includes exactly one, two or three deuterium atoms and the aryl group is selected from the group consisting of 1-naphthyl, substituted 1-naphthyl, 2-naphthyl, substituted 2-naphthyl, and phenyl groups with the structure: ##STR1## wherein R.sub.1, R.sub.2, R.sub.3, R.sub.4 and R.sub.5 are each independently, hydrogen, a C.sub.1 -C.sub.4 lower alkyl, a halogen, an amino group from the group consisting of NH.sub.2, NHR and NRR' where R and R' are each a C.sub.1 -C.sub.4 lower alkyl, a phenyl, or an alkoxy group. The present invention is also directed to processes of preparing methyl aryl sulfones and methyl aryl sulfoxides.

  13. Overexpression of peptide-methionine sulfoxide reductase in Saccharomyces cerevisiae and human T cells provides them with high resistance to oxidative stress

    PubMed Central

    Moskovitz, Jackob; Flescher, Eliezer; Berlett, Barbara S.; Azare, Janeen; Poston, J. Michael; Stadtman, Earl R.

    1998-01-01

    The yeast peptide-methionine sulfoxide reductase (MsrA) was overexpressed in a Saccharomyces cerevisiae null mutant of msrA by using a high-copy plasmid harboring the msrA gene and its promoter. The resulting strain had about 25-fold higher MsrA activity than its parent strain. When exposed to either hydrogen peroxide, paraquat, or 2,2′-azobis-(2-amidinopropane) dihydrochloride treatment, the MsrA overexpressed strain grew better, had lower free and protein-bound methionine sulfoxide and had a better survival rate under these conditions than did the msrA mutant and its parent strain. Substitution of methionine with methionine sulfoxide in a medium lacking hydrogen peroxide had little effect on the growth pattern, which suggests that the oxidation of free methionine in the growth medium was not the main cause of growth inhibition of the msrA mutant. Ultraviolet A radiation did not result in obvious differences in survival rates among the three strains. An enhanced resistance to hydrogen peroxide treatment was shown in human T lymphocyte cells (Molt-4) that were stably transfected with the bovine msrA and exposed to hydrogen peroxide. The survival rate of the transfected strain was much better than its parent strain when grown in the presence of hydrogen peroxide. These results support the proposition that the msrA gene is involved in the resistance of yeast and mammalian cells to oxidative stress. PMID:9826655

  14. Quantum Mechanics/Molecular Mechanics Studies on the Sulfoxidation of Dimethyl Sulfide by Compound I and Compound 0 of Cytochrome P450: Which Is the Better Oxidant?

    NASA Astrophysics Data System (ADS)

    Porro, Cristina S.; Sutcliffe, Michael J.; de Visser, Sam P.

    2009-06-01

    The cytochromes P450 are ubiquitous enzymes that are involved in key metabolizing processes in the body through the monoxygenation of substrates; however, their active oxidant is elusive. There have been reports that implicate that two oxidants, namely, the iron(IV)-oxo porphyrin cation radical (compound I) and the iron(III)-hydroperoxo complex (compound 0), both act as oxidants of sulfoxidation reactions, which contrasts theoretical studies on alkene epoxidation by compounds I and 0 that implicated compound 0 as a sluggish oxidant. To resolve this controversy and to establish the potency of compound I and compound 0 in sulfoxidation reactions, we have studied dimethyl sulfide sulfoxidation by both oxidants using the quantum mechanics/molecular mechanics (QM/MM) technique on cytochrome P450 enzymes and have set up a model of two P450 isozymes: P450cam and P450BM3. The calculations support earlier gas-phase density functional theory modeling and show that compound 0 is a sluggish oxidant that is unable to compete with compound I. Furthermore, compound I is shown to react with dimethyl sulfide via single-state reactivity on a dominant quartet spin state surface.

  15. Absolute solvation free energy of Li{sup +} and Na{sup +} ions in dimethyl sulfoxide solution: A theoretical ab initio and cluster-continuum model study

    SciTech Connect

    Westphal, Eduard; Pliego, Josefredo R. Jr.

    2005-08-15

    The solvation of the lithium and sodium ions in dimethyl sulfoxide solution was theoretically investigated using ab initio calculations coupled with the hybrid cluster-continuum model, a quasichemical theory of solvation. We have investigated clusters of ions with up to five dimethyl sulfoxide (DMSO) molecules, and the bulk solvent was described by a dielectric continuum model. Our results show that the lithium and sodium ions have four and five DMSO molecules into the first coordination shell, and the calculated solvation free energies are -135.5 and -108.6 kcal mol{sup -1}, respectively. These data suggest a solvation free energy value of -273.2 kcal mol{sup -1} for the proton in dimethyl sulfoxide solution, a value that is more negative than the present uncertain experimental value. This and previous studies on the solvation of ions in water solution indicate that the tetraphenylarsonium tetraphenylborate assumption is flawed and the absolute value of the free energy of transfer of ions from water to DMSO solution is higher than the present experimental values.

  16. Palliative treatment for advanced biliary adenocarcinomas with combination dimethyl sulfoxide-sodium bicarbonate infusion and S-adenosyl-L-methionine.

    PubMed

    Hoang, Ba X; Tran, Hung Q; Vu, Ut V; Pham, Quynh T; Shaw, D Graeme

    2014-09-01

    Adenocarcinoma of the gallbladder and cholangiocarcinoma account for 4% and 3%, respectively, of all gastrointestinal cancers. Advanced biliary tract carcinoma has a very poor prognosis with all current available modalities of treatment. In this pilot open-label study, the authors investigated the efficacy and safety of a combination of dimethyl sulfoxide-sodium bicarbonate (DMSO-SB) infusion and S-adenosyl-L-methionine (ademetionine) oral supplementation as palliative pharmacotherapy in nine patients with advanced nonresectable biliary tract carcinomas (ABTCs). Patients with evidence of biliary obstruction with a total serum bilirubin ≤300 μmol/L were allowed to join the study. The results of this 6-month study and follow-up of all nine patients with ABTC indicated that the investigated combination treatment improved pain control, blood biochemical parameters, and quality of life for the patients. Moreover, this method of treatment has led to a 6-month progression-free survival for all investigated patients. The treatment was well tolerated for all patients without major adverse reactions. Given that ABTC is a highly fatal malignancy with poor response to chemotherapy and targeted drugs, the authors consider that the combination of DMSO-SB and ademetionine deserves further research and application as a palliative care and survival-enhancing treatment for this group of patients. PMID:25102038

  17. Kinetic evidence that methionine sulfoxide reductase A can reveal its oxidase activity in the presence of thioredoxin.

    PubMed

    Kriznik, Alexandre; Boschi-Muller, Sandrine; Branlant, Guy

    2014-04-15

    The mouse methionine sulfoxide reductase A (MsrA) belongs to the subclass of MsrAs with one catalytic and two recycling Cys corresponding to Cys51, Cys198 and Cys206 in Escherichia coli MsrA, respectively. It was previously shown that in the absence of thioredoxin, the mouse and the E. coli MsrAs, which reduce two mol of methionine-O substrate per mol of enzyme, displays an in vitro S-stereospecific methionine oxidase activity. In the present study carried out with E. coli MsrA, kinetic evidence are presented which show that formation of the second mol of Ac-L-Met-NHMe is rate-limiting in the absence of thioredoxin. In the presence of thioredoxin, the overall rate-limiting step is associated with the thioredoxin-recycling process. Kinetic arguments are presented which support the accumulation of the E. coli MsrA under Cys51 sulfenic acid state in the presence of Trx. Thus, the methionine oxidase activity could be operative in vivo without the action of a regulatory protein in order to block the action of Trx as previously proposed. PMID:24632144

  18. Effects of Dimethyl Sulfoxide in Cholesterol-Containing Lipid Membranes: A Comparative Study of Experiments In Silico and with Cells

    PubMed Central

    de Ménorval, Marie-Amélie; Mir, Lluis M.; Fernández, M. Laura; Reigada, Ramon

    2012-01-01

    Dimethyl sulfoxide (DMSO) has been known to enhance cell membrane permeability of drugs or DNA. Molecular dynamics (MD) simulations with single-component lipid bilayers predicted the existence of three regimes of action of DMSO: membrane loosening, pore formation and bilayer collapse. We show here that these modes of action are also reproduced in the presence of cholesterol in the bilayer, and we provide a description at the atomic detail of the DMSO-mediated process of pore formation in cholesterol-containing lipid membranes. We also successfully explore the applicability of DMSO to promote plasma membrane permeability to water, calcium ions (Ca2+) and Yo-Pro-1 iodide (Yo-Pro-1) in living cell membranes. The experimental results on cells in culture can be easily explained according to the three expected regimes: in the presence of low doses of DMSO, the membrane of the cells exhibits undulations but no permeability increase can be detected, while at intermediate DMSO concentrations cells are permeabilized to water and calcium but not to larger molecules as Yo-Pro-1. These two behaviors can be associated to the MD-predicted consequences of the effects of the DMSO at low and intermediate DMSO concentrations. At larger DMSO concentrations, permeabilization is larger, as even Yo-Pro-1 can enter the cells as predicted by the DMSO-induced membrane-destructuring effects described in the MD simulations. PMID:22848583

  19. Time-resolved chemiluminescence of firefly luciferin generated by dissolving oxygen in deoxygenated dimethyl sulfoxide containing potassium tert-butoxide

    PubMed Central

    Yanagisawa, Yuki; Hasegawa, Kosuke; Wada, Naohisa; Tanaka, Masatoshi; Sekiya, Takao

    2015-01-01

    Chemiluminescence (CL) of firefly luciferin (Ln) consisting of red and green emission peaks can be generated by dissolving oxygen (O2) gas in deoxygenated dimethyl sulfoxide containing potassium tert-butoxide (t-BuOK) even without the enzyme luciferase. In this study, the characteristics of CL of Ln are examined by varying the concentrations of both Ln ([Ln]) and t-BuOK ([t-BuOK]). The time courses of the green and the red luminescence signals are also measured using a 32-channel photo sensor module. Interestingly, addition of 18-crown-6 ether (18-crown-6), a good clathrate for K+, to the reaction solution before exposure to O2 changes the luminescence from green to red when [t-BuOK] = 20 mM and [18-crown-6] = 80 mM. Based on our experimental results, we propose a two-pathway model where K+ plays an important role in the regulation of Ln CL to explain the two-color luminescence observed from electronically excited oxyluciferin via dioxetanone. PMID:27493856

  20. Methylperoxyl radicals as intermediates in the damage to DNA irradiated in aqueous dimethyl sulfoxide with gamma rays

    SciTech Connect

    Milligan, J.R.; Ng, J.Y.Y.; Wu, C.C.L.

    1996-10-01

    Using agarose gel electrophoresis, we have measured the yields of DNA single-strand breaks (SSBs) for plasmid DNA {gamma}-irradiated in aerobic aqueous solution. Incubation after irradiation with the base damage repair endonucleases formamidopyrimidine-DNA N-glycosylase (FPG) or endonuclease III (endo III) results in an increase in the yield of SSBs. In the absence of dimethyl sulfoxide (DMSO) during irradiation, this increase is consistent with the yields of known substrates for FPG and endo III as determined by gas chromatography/mass spectrometry. After irradiation in the presence of 1 mol dm{sup {minus}3} DMSO, the increase in the yield of SSBs after enzyme incubation was further enhanced by a factor of about 5 to 7. The magnitude of this effect, the inability of acrylamide or oxygen to suppress it, and its attenuation by N,N,N{prime}, N{prime}-tetramethylphenylenediamine (TMPD) or glycerol all suggest that the methylperoxyl radical (derived from DMSO) is involved as an intermediate. Reactions of the methylperoxyl radical (or some other species derived from it) do not result in strand break damage, but are responsible for DNA base damages which which are recognized by FPG and endo III. 41 refs., 5 figs.

  1. Recovery of Leptospires in Short- and Medium-Term Cryopreservation Using Different Glycerol and Dimethyl Sulfoxide Concentrations.

    PubMed

    Narduche, Lorena; Hamond, Camila; Martins, Gabriel M S; Medeiros, Marco A; Lilenbaum, Walter

    2016-02-01

    Cryopreservation is a recognized method for the maintenance of Leptospira collections. Although cryoprotectants are commonly used in order to prevent or reduce the adverse effects of freezing, there is no consensus regarding the protocols of cryopreservation. This study aimed to compare cryopreservation protocols for Leptospira using different glycerol and dimethyl sulfoxide (DMSO) concentrations. Leptospira interrogans serovar Icterohaemorrhagiae, L. interrogans serovar Bratislava, and L. borgpetersenii serovar Hardjo were used as the experimental strains. For each strain, three protocols were tested using 5% and 10% glycerol and 2.5% DMSO. For each protocol, 12 tubes containing 1.5 mL of serovar were frozen at -70°C on the same day. An aliquot of each serovar/protocol was thawed once a month throughout 1 year. The viability of leptospires was evaluated by the recovery of those at days 7, 14, and 21 after thawing. Although no significant difference was found among the leptospiral recovery rates for the 9 serovar/protocols tested, DMSO (2.5%) was shown to be slightly better than glycerol, and its use should be encouraged as a cryoprotectant for leptospires. PMID:26808330

  2. Effect of Calcium Chloride on the Permeation of the Cryoprotectant Dimethyl Sulfoxide to Japanese Whiting Sillago japonica Embryos

    NASA Astrophysics Data System (ADS)

    Rahman, Sk. Mustafizur; Majhi, Sullip Kumar; Suzuki, Toru; Strussmann, Carlos Augusto; Watanabe, Manabu

    Cryopreservation of fish eggs and embryos is a highly desired tool to promote aquaculture production and fisheries resource management, but it is still not technically feasible. The failure to develop successful cryopreservation protocols for fish embryos is largely attributed to poor cryoprotectant permeability. The purpose of this study was to test the effectiveness of CaCl2 to enhance cryoprotectant uptake by fish embryos. In this study, embryos (somites and tail elongation stages) of Japanese whiting Sillago japonica were exposed to 10 and 15% dimethyl sulfoxide (DMSO) in artificial sea water (ASW) or a solution of 0.125M CaCl2 in distilled water for 20 min at 24°C. The toxicity of all solutions was estimated from the hatching rates of the embryos and High Performance Liquid Chromatography was used to determine the amount of DMSO taken up during impregnation. The results showed that DMSO incorporation into the embryos was greatly (›50%) enhanced in the presence of CaCl2 compared to ASW. CaCl2 itself was not toxic to the embryos but, probably as a result of the enhanced DMSO uptake, caused decreases in survival of about 14-44% relative to ASW. Somites stage embryos were more tolerant than tail elongation ones to DMSO both as ASW and CaCl2 solutions. The use of CaCl2 as a vehicle for DMSO impregnation could be a promising aid for the successful cryopreservation of fish embryos.

  3. Effect of dimethyl sulfoxide on bond durability of fiber posts cemented with etch-and-rinse adhesives

    PubMed Central

    Shafiei, Fereshteh; Sarafraz, Zahra

    2016-01-01

    PURPOSE This study was undertaken to investigate whether use of an adhesive penetration enhancer, dimethyl sulfoxide (DMSO), improves bond stability of fiber posts to root dentin using two two-step etch-and-rinse resin cements. MATERIALS AND METHODS Forty human maxillary central incisor roots were randomly divided into 4 groups after endodontic treatment and post space preparation, based on the fiber post/cement used with and without DMSO pretreatment. Acid-etched root dentin was treated with 5% DMSO aqueous solution for 60 seconds or with distilled water (control) prior to the application of Excite DSC/Variolink II or One-Step Plus/Duo-link for post cementation. After micro-slicing the bonded root dentin, push-out bond strength (P-OBS) test was performed immediately or after 1-year of water storage in each group. Data were analyzed using three-way ANOVA and Student's t-test (α=.05). RESULTS A significant effect of time, DMSO treatment, and treatment × time interaction were observed (P<.001). DMSO did not affect immediate bonding of the two cements. Aging significantly reduced P-OBS in control groups (P<.001), while in DMSO-treated groups, no difference in P-OBS was observed after aging (P>.05). CONCLUSION DMSO-wet bonding might be a beneficial method in preserving the stability of resin-dentin bond strength over time when fiber post is cemented with the tested etch-and-rinse adhesive cements. PMID:27555893

  4. Amelioration of Radiation-Induced Pulmonary Fibrosis by a Water-Soluble Bifunctional Sulfoxide Radiation Mitigator (MMS350)

    PubMed Central

    Kalash, Ronny; Epperly, Michael W.; Goff, Julie; Dixon, Tracy; Sprachman, Melissa M.; Zhang, Xichen; Shields, Donna; Cao, Shaonan; Franicola, Darcy; Wipf, Peter; Berhane, Hebist; Wang, Hong; Au, Jeremiah; Greenberger, Joel S.

    2014-01-01

    A water-soluble ionizing radiation mitigator would have considerable advantages for the management of acute and chronic effects of ionizing radiation. We report that a novel oxetanyl sulfoxide (MMS350) is effective both as a protector and a mitigator of clonal mouse bone marrow stromal cell lines in vitro, and is an effective in vivo mitigator when administered 24 h after 9.5 Gy (LD100/30) total-body irradiation of C57BL/6NHsd mice, significantly improving survival (P =0.0097). Furthermore, MMS350 (400 μM) added weekly to drinking water after 20 Gy thoracic irradiation significantly decreased: expression of pulmonary inflammatory and profibrotic gene transcripts and proteins; migration into the lungs of bone marrow origin luciferase+/GFP+ (luc+/GFP+) fibroblast progenitors (in both luc+ marrow chimeric and luc+ stromal cell line injected mouse models) and decreased radiation-induced pulmonary fibrosis (P < 0.0001). This nontoxic and orally administered small molecule may be an effective therapeutic in clinical radiotherapy and as a counter measure against the acute and chronic effects of ionizing radiation. PMID:24125487

  5. A theoretical investigation of the interactions between hydroxyl-functionalized ionic liquid and water/methanol/dimethyl sulfoxide.

    PubMed

    Zhao, Shuang; Tian, XinZhe; Ren, YunLai; Wang, JianJi; Liu, JunNa; Ren, YunLi

    2016-08-01

    Density functional calculations have been used to investigate the interactions of 1-(2-hydroxyethyl)-3-methylimidazolium ([C2OHmim](+))-based ionic liquids (hydroxyl ILs) with water (H2O), methanol (CH3OH), and dimethyl sulfoxide (DMSO). It was found that the cosolvent molecules interact with the anion and cation of each ionic liquid through different atoms, i.e., H and O atoms, respectively. The interactions between the cosolvent molecules and 1-ethyl-3-methylimizolium ([C2mim](+))-based ionic liquids (nonhydroxyl ILs) were also studied for comparison. In the cosolvent-[nonhydroxyl ILs] systems, a furcated H-bond was formed between the O atom of the cosolvent molecule and the C2-H and C6-H, while there were always H-bonds involving the OH group of the cation in the cosolvent-[hydroxyl ILs] systems. Introducing an OH group on the ethyl side of the imidazolium ring may change the order of solubility of the molecular liquids. PMID:27480880

  6. Viscosities of the ternary solution dimethyl sulfoxide/water/sodium chloride at subzero temperatures and their application in cryopreservation.

    PubMed

    Zhang, Shaozhi; Yu, Xiaoyi; Chen, Zhaojie; Chen, Guangming

    2013-04-01

    Vitrification is considered as the most promising method for long-term storage of tissues and organs. An effective way to reduce the accompanied cryoprotectant (CPA) toxicity, during CPA addition/removal, is to operate at low temperatures. The permeation process of CPA into/out of biomaterials is affected by the viscosity of CPA solution, especially at low temperatures. The objective of the present study is to measure the viscosity of the ternary solution, dimethyl sulfoxide (Me2SO)/water/sodium chloride (NaCl), at low temperatures and in a wide range of concentrations. A rotary viscometer coupled with a low temperature thermostat bath was used. The measurement was carried out at temperatures from -10 to -50°C. The highest mass fraction of Me2SO was 75% (w/w) and the lowest mass fraction of Me2SO was the value that kept the solution unfrozen at the measurement temperature. The concentration of NaCl was kept as a constant [0.85% (w/w), the normal salt content of extracellular fluids]. The Williams-Landel-Ferry (WLF) model was employed to fit the obtained viscosity data. As an example, the effect of solution viscosity on modeling the permeation of Me2SO into articular cartilage was qualitatively analyzed. PMID:23376371

  7. Formation and Luminescence Phenomena of LaF3:Ce3+ Nanoparticles and Lanthanide-Organic Compounds in Dimethyl Sulfoxide

    SciTech Connect

    Yao, Mingzhen; Joly, Alan G.; Chen, Wei

    2010-01-21

    LaF3:Ce3+ doped nanoparticles were synthesized at different temperatures in dimethyl sulfoxide by the chemical reaction of lanthanum nitrate hydrate and cerium nitrate hexahydrate with ammonium fluoride. The formation of Ce3+ doped LaF3 nanoparticles is confirmed by X-ray diffraction and high resolution transmission electron microscopy. An intense emission at around 310 nm from the d - f transition of Ce3+ was observed from the LaF3:Ce3+ powder samples. However, in solution samples, the ultraviolet emission from Ce3+ is mostly absent, but intense luminescence is observed in the visible range from blue to red. The emission wavelength of the solution samples is dependent on the reaction time and temperature. More interestingly, the emission wavelength varies with the excitation wavelength. Most likely, this emission is from the metalorganic compounds of Ce3+ or La3+ and DMSO as similar phenomena are also observed when lanthanum nitrate hydrate or cerium nitrate hexahydrate are heated in DMSO.

  8. Positive and negative ion formation in deep-core excited molecules: S 1s excitation in dimethyl sulfoxide

    SciTech Connect

    Coutinho, L. H.; Gardenghi, D. J.; Schlachter, A. S.; Souza, G. G. B. de; Stolte, W. C.

    2014-01-14

    The photo-fragmentation of the dimethyl sulfoxide (DMSO) molecule was studied using synchrotron radiation and a magnetic mass spectrometer. The total cationic yield spectrum was recorded in the photon energy region around the sulfur K edge. The sulfur composition of the highest occupied molecular orbital's and lowest unoccupied molecular orbital's in the DMSO molecule has been obtained using both ab initio and density functional theory methods. Partial cation and anion-yield measurements were obtained in the same energy range. An intense resonance is observed at 2475.4 eV. Sulfur atomic ions present a richer structure around this resonant feature, as compared to other fragment ions. The yield curves are similar for most of the other ionic species, which we interpret as due to cascade Auger processes leading to multiply charged species which then undergo Coulomb explosion. The anions S{sup −}, C{sup −}, and O{sup −} are observed for the first time in deep-core-level excitation of DMSO.

  9. Cloning and expression of the sulfoxide/sulfone/sulfonate/sulfate genes in Pseudomonads and Thiobacillae. Tenth quarterly report

    SciTech Connect

    Krawiec, S.

    1992-02-07

    The original conception of the work was that genetic determinants of the sulfoxide/sulfone/sulfonate/sulfate (``4S``) pathway in Pseudomonas spp. would be cloned in vivo and then transferred to Thiobacillus spp. This ambition remains an appealing prospect; however, fulfilling that ambition has been confounded by an instability observed in the DbtS{sup +} phenotype in Pseudomonas spp. But the persisting interest in the phenotype has lead to isolation of fresh strains which have a DbtS{sup +} phenotype. One strain in particular, N1-36, has been the focus of extensive characterizations in long-term cultures. During the present quarter, seven cultures maintained in a ``fermentor`` for a week or longer have been run to determine rate and extent of growth, extent of conversion of dibenzothiophene (DBT) or dibenzosulfone (DBTO{sub 2}) to monohydroxybiphenyl (OH-BP), effect of pH maintained at 6.0, and the effect of adding glucose to cultures in which the amount of glucose had been diminished by bacterial consumption. In addition, a study of the effectiveness of using R68.445 as a vehicle for in vivo cloning of genes was completed this semester, and introduction of DbtS{sup +} determinants into Thiobacillus spp. continues to be an important goal.

  10. Cloning and expression of the sulfoxide/sulfone/sulfonate/sulfate genes in Pseudomonads and Thiobacillae. [Pseudomonas, Thiobacillus, Rhodococcus

    SciTech Connect

    Krawiec, S.

    1992-02-07

    The original conception of the work was that genetic determinants of the sulfoxide/sulfone/sulfonate/sulfate ( 4S'') pathway in Pseudomonas spp. would be cloned in vivo and then transferred to Thiobacillus spp. This ambition remains an appealing prospect; however, fulfilling that ambition has been confounded by an instability observed in the DbtS{sup +} phenotype in Pseudomonas spp. But the persisting interest in the phenotype has lead to isolation of fresh strains which have a DbtS{sup +} phenotype. One strain in particular, N1-36, has been the focus of extensive characterizations in long-term cultures. During the present quarter, seven cultures maintained in a fermentor'' for a week or longer have been run to determine rate and extent of growth, extent of conversion of dibenzothiophene (DBT) or dibenzosulfone (DBTO{sub 2}) to monohydroxybiphenyl (OH-BP), effect of pH maintained at 6.0, and the effect of adding glucose to cultures in which the amount of glucose had been diminished by bacterial consumption. In addition, a study of the effectiveness of using R68.445 as a vehicle for in vivo cloning of genes was completed this semester, and introduction of DbtS{sup +} determinants into Thiobacillus spp. continues to be an important goal.

  11. Dimethyl sulfoxide-sodium bicarbonate infusion for palliative care and pain relief in patients with metastatic prostate cancer.

    PubMed

    Hoang, Ba X; Le, Bao T; Tran, Hau D; Hoang, Cuong; Tran, Hung Q; Tran, Dao M; Pham, Cu Q; Pham, Tuan D; Ha, Trung V; Bui, Nga T; Shaw, D Graeme

    2011-01-01

    Prostate cancer (adenocarcinoma of the prostate) is the most widespread cancer in men. It causes significant suffering and mortality due to metastatic disease. The main therapy for metastatic prostate cancer (MPC) includes androgen manipulation, chemotherapy, and radiotherapy and/or radioisotopes. However, these therapeutic approaches are considered palliative at this stage, and their significant side effects can cause further decline in patients' quality of life and increase non-cancer-related morbidity/mortality. In this study, the authors have used the infusion of dimethyl sulfoxide-sodium bicarbonate (DMSO-SB) to treat 18 patients with MPC. The 90-day follow-up of the patients having undergone the proposed therapeutic regimen showed significant improvement in clinical symptoms, blood and biochemistry tests, and quality of life. There were no major side effects from the treatment. In searching for new and better methods for palliative treatment and pain relief, this study strongly suggested therapy with DMSO-SB infusions could provide a rational alternative to conventional treatment for patients with MPC. PMID:21936635

  12. Amelioration of radiation-induced pulmonary fibrosis by a water-soluble bifunctional sulfoxide radiation mitigator (MMS350).

    PubMed

    Kalash, Ronny; Epperly, Michael W; Goff, Julie; Dixon, Tracy; Sprachman, Melissa M; Zhang, Xichen; Shields, Donna; Cao, Shaonan; Franicola, Darcy; Wipf, Peter; Berhane, Hebist; Wang, Hong; Au, Jeremiah; Greenberger, Joel S

    2013-11-01

    A water-soluble ionizing radiation mitigator would have considerable advantages for the management of acute and chronic effects of ionizing radiation. We report that a novel oxetanyl sulfoxide (MMS350) is effective both as a protector and a mitigator of clonal mouse bone marrow stromal cell lines in vitro, and is an effective in vivo mitigator when administered 24 h after 9.5 Gy (LD100/30) total-body irradiation of C57BL/6NHsd mice, significantly improving survival (P = 0.0097). Furthermore, MMS350 (400 μM) added weekly to drinking water after 20 Gy thoracic irradiation significantly decreased: expression of pulmonary inflammatory and profibrotic gene transcripts and proteins; migration into the lungs of bone marrow origin luciferase+/GFP+ (luc+/GFP+) fibroblast progenitors (in both luc+ marrow chimeric and luc+ stromal cell line injected mouse models) and decreased radiation-induced pulmonary fibrosis (P < 0.0001). This nontoxic and orally administered small molecule may be an effective therapeutic in clinical radiotherapy and as a counter measure against the acute and chronic effects of ionizing radiation. PMID:24125487

  13. Deficiency of methionine sulfoxide reductase A causes cellular dysfunction and mitochondrial damage in cardiac myocytes under physical and oxidative stresses

    SciTech Connect

    Nan, Changlong; Li, Yuejin; Jean-Charles, Pierre-Yves; Chen, Guozhen; Kreymerman, Alexander; Prentice, Howard; Weissbach, Herbert; Huang, Xupei

    2010-11-26

    Research highlights: {yields} Deficiency of MsrA in the heart renders myocardial cells more sensitive to oxidative stress. {yields} Mitochondrial damage happens in the heart lacking MsrA. {yields} More protein oxidation in myocardial cells lacking MsrA. {yields} MsrA protects the heart against oxidative stress. -- Abstract: Methionine sulfoxide reductase A (MsrA) is an enzyme that reverses oxidation of methionine in proteins. Using a MsrA gene knockout (MsrA{sup -/-}) mouse model, we have investigated the role of MsrA in the heart. Our data indicate that cellular contractility and cardiac function are not significantly changed in MsrA{sup -/-} mice if the hearts are not stressed. However, the cellular contractility, when stressed using a higher stimulation frequency (2 Hz), is significantly reduced in MsrA{sup -/-} cardiac myocytes. MsrA{sup -/-} cardiac myocytes also show a significant decrease in contractility after oxidative stress using H{sub 2}O{sub 2}. Corresponding changes in Ca{sup 2+} transients are observed in MsrA{sup -/-} cardiomyocytes treated with 2 Hz stimulation or with H{sub 2}O{sub 2}. Electron microscope analyses reveal a dramatic morphological change of mitochondria in MsrA{sup -/-} mouse hearts. Further biochemical measurements indicate that protein oxidation levels in MsrA{sup -/-} mouse hearts are significantly higher than those in wild type controls. Our study demonstrates that the lack of MsrA in cardiac myocytes reduces myocardial cell's capability against stress stimulations resulting in a cellular dysfunction in the heart.

  14. Regulatory effect of Dimethyl Sulfoxide (DMSO) on astrocytic reactivity in a murine model of cerebral infarction by arterial embolization

    PubMed Central

    Rengifo Valbuena, Carlos Augusto; Ávila Rodríguez, Marco Fidel; Céspedes Rubio, Angel

    2013-01-01

    Introduction: The pathophysiology of cerebral ischemia is essential for early diagnosis, neurologic recovery, the early onset of drug treatment and the prognosis of ischemic events. Experimental models of cerebral ischemia can be used to evaluate the cellular response phenomena and possible neurological protection by drugs. Objective: To characterize the cellular changes in the neuronal population and astrocytic response by the effect of Dimethyl Sulfoxide (DMSO) on a model of ischemia caused by cerebral embolism. Methods: Twenty Wistar rats were divided into four groups (n= 5). The infarct was induced with α-bovine thrombin (40 NIH/Unit.). The treated group received 90 mg (100 μL) of DMSO in saline (1:1 v/v) intraperitoneally for 5 days; ischemic controls received only NaCl (placebo) and two non-ischemic groups (simulated) received NaCl and DMSO respectively. We evaluated the neuronal (anti-NeuN) and astrocytic immune-reactivity (anti-GFAP). The results were analyzed by densitometry (NIH Image J-Fiji 1.45 software) and analysis of variance (ANOVA) with the Graph pad software (Prism 5). Results: Cerebral embolism induced reproducible and reliable lesions in the cortex and hippocampus (CA1)., similar to those of focal models. DMSO did not reverse the loss of post-ischemia neuronal immune-reactivity, but prevented the morphological damage of neurons, and significantly reduced astrocytic hyperactivity in the somato-sensory cortex and CA1 (p <0.001). Conclusions: The regulatory effect of DMSO on astrocyte hyperreactivity and neuronal-astroglial cytoarchitecture , gives it potential neuroprotective properties for the treatment of thromboembolic cerebral ischemia in the acute phase. PMID:24892319

  15. Evaluation of the cytotoxicity effect of dimethyl sulfoxide (DMSO) on Caco2/TC7 colon tumor cell cultures.

    PubMed

    Da Violante, Georges; Zerrouk, Naima; Richard, Isabelle; Provot, Gérard; Chaumeil, Jean Claude; Arnaud, Philippe

    2002-12-01

    Dimethyl sulfoxide (DMSO) is usually used to solubilize poorly soluble drugs in permeation assays such as that using Caco2 enterocyte-like cells. The objective of this study was to evaluate the toxicity of DMSO on Caco2/TC7 cells and determinate the maximal concentration usable in permeation experiments. Caco2/TC7 cells were cultured for 21 d on 96-well plates for evaluation of toxicity. The determination of lactate dehydrogenase (LDH) release in cell supernatant and the measurement of Neutral Red (NR) uptake are used for cytotoxicity assays. DMSO solutions (0-100%) in Hank's balanced salt solution containing HEPES (25 mM), pH 7.4, were incubated with Caco-2/TC7 cells on 96 well plates. Caco2/TC7 cells were cultured on Transwell-Clear inserts to evaluate the influence of DMSO on the apparent permeability of the paracellular marker mannitol. DMSO 10% did not induce any significant increase in LDH release whereas a significant increase in LDH activity (ANOVA, p<0.05) occurred at a DMSO concentration of 20 to 50%. NR incorporation in viable cells was statistically reduced by 27 to 36% at DMSO concentration of 20% up to 100% (ANOVA, p>0.05). No statistical difference (p<0.05) in apparent mannitol permeability was observed between the control and 10% DMSO groups. In conclusion, at concentrations of up to 10%, DMSO did not produce any significant alteration in apical membrane permeability or on cell-to-cell tight junctional complexes. PMID:12499647

  16. Determination of S-methyl-, S-propyl-, and S-propenyl-L-cysteine sulfoxides by gas chromatography-mass spectrometry after tert-butyldimethylsilylation.

    PubMed

    Tsuge, Kouichiro; Kataoka, Mieko; Seto, Yasuo

    2002-07-31

    A gas chromatographic-mass spectrometric method for the determination of S-methyl-L-cysteine sulfoxide (1), S-propyl-L-cysteine sulfoxide (2), and S-propenyl-L-cysteine sulfoxide (3), specific marker compounds in the genus Allium, is described. The target amino acids were converted to the tert-butyldimethylsilyl derivatives. The products were silylated on the amino and carboxyl groups and on an additional oxygen atom and were separated on a nonpolar capillary column. That incorporation of three tert-butyldimethylsilyl groups had occurred was verified by mass spectrometry, which gave an m/z 302 fragment as base peak (amino acid side chain eliminated ion) and m/z 436 (1), 464 (2), or 462 (3) as major peaks (tert-butyl function eliminated ion), by electron impact ionization. The detection limits for 1 and 2 under selected ion monitoring at m/z 436 (1) and m/z 464 (2), respectively, were determined to be 0.3 and 1.8 ng per injection. To clean up the analytes from the solvent extract of onion, as a representative food material, onion, the sample solution was subjected to combined solid phase extraction. The eluate from a Sep-Pak C(18) cartridge was applied to a Bond Elut SCX cartridge (H(+) form), followed by washing with 0.1 M hydrochloric acid and elution with 0.5 M ammonia. From a simulated matrix solution containing 5% sucrose, 1 and 2 were extracted quantitatively, and the detection yield was approximately 75%. The contents of 1, 2, and 3 in commercial onion were estimated to be 0.3, 3.1, and 3.0 mg, respectively, per gram of fresh weight. PMID:12137458

  17. Enantiomeric resolution of albendazole sulfoxide by semipreparative HPLC and in vitro study of growth inhibitory effects on human cancer cell lines.

    PubMed

    Belaz, Kátia Roberta A; Denadai, Marina; Almeida, Ana Paula; Lima, Raquel T; Vasconcelos, M Helena; Pinto, M Madalena; Cass, Quezia B; Oliveira, Regina V

    2012-07-01

    Analytical and semipreparative high performance liquid chromatography methods using polysaccharide-based chiral stationary phases were developed for the enantiomeric resolution of albendazol sulfoxide. The enantioseparation of this compound was evaluated with four chiral stationary phases: cellulose and amylose tris(3,5-dimethylphenylcarbamate), amylose tris[(S)-1-phenylethylcarbamate] and amylose tris(3,5-dimethoxyphenylcarbamate), under three elution conditions: normal, reversed-phase and polar organic mode. The influences of the mobile phase and of the structure of the chiral stationary phase on the enantiomeric separation are discussed. The best chiral performances were achieved on an amylose tris(3,5-dimethylphenylcarbamate) phase under normal (R(s)=4.96) and polar organic mode (R(s)=2.60 and 3.09). A polar organic condition using methanol as mobile phase offered shorter retention factors (k(1)=0.34) and was scaled up to semipreparative HPLC to obtain milligram quantities of both albendazole sulfoxide enantiomers for further in vitro studies. Optical rotation and circular dichroism of both enantiomers of albendazole sulfoxide was determined. The compounds ABZ, ABZ-SO, (R)-(+)-ABZ-SO and (S)-(-)-ABZ-SO were all evaluated regarding their capacity to inhibit the in vitro growth of three human tumor cell lines: MCF-7 (breast adenocarcinoma), NCI-H460 (non-small cell lung cancer) and A375-C5 (melanoma). In addition, the effect of the (R)-(+)-ABZ-SO compound in the cell cycle profile and apoptosis of MCF-7 cells were also studied. Results indicated that compound ABZ was the most potent regarding cell growth inhibition and that the (+)-(R)-ABZ was a more potent inhibitor of cell growth than the (S)-(-)-ABZ-SO, particularly in the MCF-7 cell line. In addition, the (R)-(+)-ABZ-SO significantly increased the levels of apoptosis of the MCF-7 cells. PMID:22487592

  18. Volumetric Properties of the Mixture Dimethyl sulfoxide C2H6OS + C3H6O3 Dimethyl carbonate (VMSD1212, LB5136_V)

    NASA Astrophysics Data System (ADS)

    Cibulka, I.; Fontaine, J.-C.; Sosnkowska-Kehiaian, K.; Kehiaian, H. V.

    This document is part of Subvolume C 'Binary Liquid Systems of Nonelectrolytes III' of Volume 26 'Heats of Mixing, Vapor-Liquid Equilibrium, and Volumetric Properties of Mixtures and Solutions' of Landolt-Börnstein Group IV 'Physical Chemistry'. It contains the Chapter 'Volumetric Properties of the Mixture Dimethyl sulfoxide C2H6OS + C3H6O3 Dimethyl carbonate (VMSD1212, LB5136_V)' providing data by calculation of molar excess volume from low-pressure density measurements at variable mole fraction and constant temperature.

  19. Heat of Mixing and Solution of Dimethyl sulfoxide C2H6OS + C3H6O3 Dimethyl carbonate (HMSD1111, LB4314_H)

    NASA Astrophysics Data System (ADS)

    Cibulka, I.; Fontaine, J.-C.; Sosnkowska-Kehiaian, K.; Kehiaian, H. V.

    This document is part of Subvolume C 'Binary Liquid Systems of Nonelectrolytes III' of Volume 26 'Heats of Mixing, Vapor-Liquid Equilibrium, and Volumetric Properties of Mixtures and Solutions' of Landolt-Börnstein Group IV 'Physical Chemistry'. It contains the Chapter 'heat of Mixing and Solution of Dimethyl sulfoxide C2H6OS + C3H6O3 Dimethyl carbonate (HMSD1111, LB4314_H)' providing data from direct low-pressure calorimetric measurement of molar excess enthalpy at variable mole fraction and constant temperature.

  20. Volumetric Properties of the Mixture Dimethyl sulfoxide C2H6OS + C5H10O3 Diethyl carbonate (VMSD1212, LB5137_V)

    NASA Astrophysics Data System (ADS)

    Cibulka, I.; Fontaine, J.-C.; Sosnkowska-Kehiaian, K.; Kehiaian, H. V.

    This document is part of Subvolume C 'Binary Liquid Systems of Nonelectrolytes III' of Volume 26 'Heats of Mixing, Vapor-Liquid Equilibrium, and Volumetric Properties of Mixtures and Solutions' of Landolt-Börnstein Group IV 'Physical Chemistry'. It contains the Chapter 'Volumetric Properties of the Mixture Dimethyl sulfoxide C2H6OS + C5H10O3 Diethyl carbonate (VMSD1212, LB5137_V)' providing data by calculation of molar excess volume from low-pressure density measurements at variable mole fraction and constant temperature.

  1. Volumetric Properties of the Mixture Dimethyl sulfoxide C2H6OS + C5H10O3 Diethyl carbonate (VMSD1111, LB5134_V)

    NASA Astrophysics Data System (ADS)

    Cibulka, I.; Fontaine, J.-C.; Sosnkowska-Kehiaian, K.; Kehiaian, H. V.

    This document is part of Subvolume C 'Binary Liquid Systems of Nonelectrolytes III' of Volume 26 'Heats of Mixing, Vapor-Liquid Equilibrium, and Volumetric Properties of Mixtures and Solutions' of Landolt-Börnstein Group IV 'Physical Chemistry'. It contains the Chapter 'Volumetric Properties of the Mixture Dimethyl sulfoxide C2H6OS + C5H10O3 Diethyl carbonate (VMSD1111, LB5134_V)' providing data from direct low-pressure measurement of mass density at variable mole fraction and constant temperature, in the single-phase region(s).

  2. Volumetric Properties of the Mixture Dimethyl sulfoxide C2H6OS + C3H6O3 Dimethyl carbonate (VMSD1111, LB5133_V)

    NASA Astrophysics Data System (ADS)

    Cibulka, I.; Fontaine, J.-C.; Sosnkowska-Kehiaian, K.; Kehiaian, H. V.

    This document is part of Subvolume C 'Binary Liquid Systems of Nonelectrolytes III' of Volume 26 'Heats of Mixing, Vapor-Liquid Equilibrium, and Volumetric Properties of Mixtures and Solutions' of Landolt-Börnstein Group IV 'Physical Chemistry'. It contains the Chapter 'Volumetric Properties of the Mixture Dimethyl sulfoxide C2H6OS + C3H6O3 Dimethyl carbonate (VMSD1111, LB5133_V)' providing data from direct low-pressure measurement of mass density at variable mole fraction and constant temperature, in the single-phase region(s).

  3. Heat of Mixing and Solution of Dimethyl sulfoxide C2H6OS + C5H10O3 Diethyl carbonate (HMSD1111, LB4315_H)

    NASA Astrophysics Data System (ADS)

    Cibulka, I.; Fontaine, J.-C.; Sosnkowska-Kehiaian, K.; Kehiaian, H. V.

    This document is part of Subvolume C 'Binary Liquid Systems of Nonelectrolytes III' of Volume 26 'Heats of Mixing, Vapor-Liquid Equilibrium, and Volumetric Properties of Mixtures and Solutions' of Landolt-Börnstein Group IV 'Physical Chemistry'. It contains the Chapter 'heat of Mixing and Solution of Dimethyl sulfoxide C2H6OS + C5H10O3 Diethyl carbonate (HMSD1111, LB4315_H)' providing data from direct low-pressure calorimetric measurement of molar excess enthalpy at variable mole fraction and constant temperature.

  4. Volumetric Properties of the Mixture Dimethyl sulfoxide C2H6OS + C3H3N Propenenitrile (VMSD1111, LB4256_V)

    NASA Astrophysics Data System (ADS)

    Cibulka, I.; Fontaine, J.-C.; Sosnkowska-Kehiaian, K.; Kehiaian, H. V.

    This document is part of Subvolume A 'Binary Liquid Systems of Nonelectrolytes I' of Volume 26 'Heats of Mixing, Vapor-Liquid Equilibrium, and Volumetric Properties of Mixtures and Solutions' of Landolt-Börnstein Group IV 'Physical Chemistry'. It contains the Chapter 'Volumetric Properties of the Mixture Dimethyl sulfoxide C2H6OS + C3H3N Propenenitrile (VMSD1111, LB4256_V)' providing data from direct low-pressure measurement of mass density at variable mole fraction and constant temperature, in the single-phase region(s).

  5. Volumetric Properties of the Mixture Dimethyl sulfoxide C2H6OS + C3H3N Propenenitrile (VMSD1212, LB4258_V)

    NASA Astrophysics Data System (ADS)

    Cibulka, I.; Fontaine, J.-C.; Sosnkowska-Kehiaian, K.; Kehiaian, H. V.

    This document is part of Subvolume A 'Binary Liquid Systems of Nonelectrolytes I' of Volume 26 'Heats of Mixing, Vapor-Liquid Equilibrium, and Volumetric Properties of Mixtures and Solutions' of Landolt-Börnstein Group IV 'Physical Chemistry'. It contains the Chapter 'Volumetric Properties of the Mixture Dimethyl sulfoxide C2H6OS + C3H3N Propenenitrile (VMSD1212, LB4258_V)' providing data by calculation of molar excess volume from low-pressure density measurements at variable mole fraction and constant temperature.

  6. Volumetric Properties of the Mixture Dimethyl sulfoxide C2H6OS + C3H3N Propenenitrile (VMSD1412, LB4276_V)

    NASA Astrophysics Data System (ADS)

    Cibulka, I.; Fontaine, J.-C.; Sosnkowska-Kehiaian, K.; Kehiaian, H. V.

    This document is part of Subvolume A 'Binary Liquid Systems of Nonelectrolytes I' of Volume 26 'Heats of Mixing, Vapor-Liquid Equilibrium, and Volumetric Properties of Mixtures and Solutions' of Landolt-Börnstein Group IV 'Physical Chemistry'. It contains the Chapter 'Volumetric Properties of the Mixture Dimethyl sulfoxide C2H6OS + C3H3N Propenenitrile (VMSD1412, LB4276_V)' providing data by calculation of isentropic compressibility from low-pressure density and thermodynamic speed of sound data at variable mole fraction and constant temperature, in the single-phase region(s).

  7. Volumetric Properties of the Mixture Dimethyl sulfoxide C2H6OS + C3H3N Propenenitrile (VMSD1511, LB4270_V)

    NASA Astrophysics Data System (ADS)

    Cibulka, I.; Fontaine, J.-C.; Sosnkowska-Kehiaian, K.; Kehiaian, H. V.

    This document is part of Subvolume A 'Binary Liquid Systems of Nonelectrolytes I' of Volume 26 'Heats of Mixing, Vapor-Liquid Equilibrium, and Volumetric Properties of Mixtures and Solutions' of Landolt-Börnstein Group IV 'Physical Chemistry'. It contains the Chapter 'Volumetric Properties of the Mixture Dimethyl sulfoxide C2H6OS + C3H3N Propenenitrile (VMSD1511, LB4270_V)' providing data from direct measurement of low-pressure thermodynamic speed of sound at variable mole fraction and constant temperature, in the single-phase region(s).

  8. Dimethyl Sulfoxide and N-Iodosuccinimide Promoted 5-exo-dig Oxidative Cyclization of Yne-Tethered Ynamide: Access to Pyrrolidones and Spiro-pyrrolidones.

    PubMed

    Prabagar, B; Nayak, Sanatan; Prasad, Rangu; Sahoo, Akhila K

    2016-07-01

    An unprecedented metal-free dimethyl sulfoxide (DMSO) and N-iodosuccinimide mediated regioselective 5-exo-dig oxidative cyclization of an in situ generated enol equivalent of amides from ynamides bearing internal alkynes is demonstrated. The reaction allows easy access to functionalized pyrrolidone skeletons. Pyrrolidones having 3-o-biaryl motifs successfully undergo intramolecular electrophilic cyclization with the α,β-unsaturated olefin, furnishing spiro-pyrrolidone motifs. A one-pot sequential 5-exo-dig cyclization of the yne-tethered ynamides, followed by electrophilic cyclization of the pyrrolidone, is presented. The role of DMSO in the transformation is clarified, and a tentative reaction pathway is proposed. PMID:27332985

  9. Combined application of neutron and synchrotron radiation for investigation of the influence of dimethyl sulfoxide on the structure and properties of the dipalmitoylphosphatidylcholine membrane

    SciTech Connect

    Kiselev, M. A.

    2007-05-15

    The influence of dimethyl sulfoxide (DMSO) on the structure and properties of the dipalmitoylphosphatidylcholine membrane was studied at positive temperatures by a combination of X-ray diffraction and small-angle neutron scattering. Penetration of DMSO molecules into the lipid membrane was found to depend on the mole fraction of DMSO in an aqueous solution, X{sub DMSO}. At X{sub DMSO} > 0.08 the SO group penetrates into the bilayer polar region, thus resulting in structural alterations. At X{sub DMSO} > 0.2 defects in the membrane surface are developed.

  10. Expanding the nasturlexin family: Nasturlexins C and D and their sulfoxides are phytoalexins of the crucifers Barbarea vulgaris and B. verna.

    PubMed

    Pedras, M Soledade C; Alavi, Mahla; To, Q Huy

    2015-10-01

    The metabolites produced in leaves of the crucifers winter cress (Barbarea vulgaris) and upland cress (Barbarea verna) abiotically elicited were investigated and their chemical structures were elucidated by analyses of spectroscopic data and confirmed by syntheses. Nasturlexins C and D and their sulfoxides are cruciferous phytoalexins displaying antifungal activity against the crucifer pathogens Alternaria brassicicola, Leptosphaeria maculans and Sclerotinia sclerotiorum. The biosynthesis of these metabolites is proposed based on pathways of cruciferous indolyl phytoalexins. This work indicates that B. vulgaris and B. verna have great potential as sources of defense pathways transferable to agriculturally important crops within the Brassica species. PMID:26318326

  11. Reactive oxygen species modulate the differential expression of methionine sulfoxide reductase genes in Chlamydomonas reinhardtii under high light illumination.

    PubMed

    Chang, Hsueh-Ling; Tseng, Yu-Lu; Ho, Kuan-Lin; Shie, Shu-Chiu; Wu, Pei-Shan; Hsu, Yuan-Ting; Lee, Tse-Min

    2014-04-01

    Illumination of Chlamydomonas reinhardtii cells at 1000 (high light, HL) or 3000 (very high light, VHL) µmol photons m(-2)  s(-1) intensity increased superoxide anion radical (O(2)(•-)) and hydrogen peroxide (H(2)O(2)) production, and VHL illumination also increased the singlet oxygen ((1)O(2)) level. HL and VHL illumination decreased methionine sulfoxide reductase A4 (CrMSRA4) transcript levels but increased CrMSRA3, CrMSRA5 and CrMSRB2.1 transcripts levels. CrMSRB2.2 transcript levels increased only under VHL conditions. The role of reactive oxygen species (ROS) on CrMSR expression was studied using ROS scavengers and generators. Treatment with dimethylthiourea (DMTU), a H(2)O(2) scavenger, suppressed HL- and VHL-induced CrMSRA3, CrMSRA5 and CrMSRB2.1 expression, whereas H(2)O(2) treatment stimulated the expression of these genes under 50 µmol photons m(-2)  s(-1) conditions (low light, LL). Treatment with diphenylamine (DPA), a (1)O(2) quencher, reduced VHL-induced CrMSRA3, CrMSRA5 and CrMSRB2.2 expression and deuterium oxide, which delays (1)O(2) decay, enhanced these gene expression, whereas treatment with (1)O(2) (rose bengal, methylene blue and neutral red) or O(2)(•-) (menadione and methyl viologen) generators under LL conditions induced their expression. DPA treatment inhibited the VHL-induced decrease in CrMSRA4 expression, but other ROS scavengers and ROS generators did not affect its expression under LL or HL conditions. These results demonstrate that the differential expression of CrMSRs under HL illumination can be attributed to different types of ROS. H(2)O(2), O(2) (•-) and (1)O(2) modulate CrMSRA3 and CrMSRA5 expression, whereas H(2)O(2) and O(2)(•-) regulate CrMSRB2.1 and CrMSRB2.2 expression, respectively. (1)O(2) mediates the decrease of CrMSRA4 expression by VHL illumination, but ROS do not modulate its decrease under HL conditions. PMID:24102363

  12. Detection of thiodiglycol and its sulfoxide and sulfone analogues in environmental waters by high performance liquid chromatography. Final report, January-October 1991

    SciTech Connect

    Bossle, P.C.; Ellzy, M.W.; Martin, J.J.

    1993-06-01

    2,2'-Thiodiethanol (thiodiglycol) (TDG), the major hydrolytic breakdown product of mustard gas (bis(2-chloroethyl)sulfide), is oxidized gradually in water to its sulfoxide analogue 2,2'-sulfinyldiethanol (TDGO). In the presence of sunlight, further oxidation is then thought to occur with the formation of the sulfone analogue 2,2'-sulfonyldiethanol (TDGO2). A new high performance liquid chromatography method is described to directly separate and quantitate trace amounts of TDG, TDGO, and TDGO2 in surface water and seawater. Separations in this study were carried out on an ion-exclusion column using an isocratic mobile phase consisting of 100 mM perchloric acid. Detection and quantitation of TDG, TDGO, and TDGO2 were by ultraviolet (208 nM) and pulsed amperometric detection. Using a platinum working electrode, the sampling, cleaning, and regenerating potentials were 0.3, 1.25, and -0.10V, respectively. Detection limits for TDG, TDGO, and TDGO2 were in the 40-80 ng range.... Mustard gas, 2,2'-Sulfinyldiethanol, Thiodiglycol, Thiodiglycol sulfoxide 2,2'-Thiodiethanol, Thiodiglycol sulfone, 2,2'-Sulfonyldiethanol, Pulsed amperometric detection, High Performance Liquid Chromatography(HPLC).

  13. Silencing of the methionine sulfoxide reductase A gene results in loss of mitochondrial membrane potential and increased ROS production in human lens cells

    PubMed Central

    Marchetti, Maria A.; Lee, Wanda; Cowell, Tracy L.; Wells, Tracy M.; Weissbach, Herbert; Kantorow, Marc

    2010-01-01

    Accumulation of methionine sulfoxide (Met(O)) is a significant feature of human cataract and previous studies have shown that methionine sulfoxide reductase A (MsrA), which acts to repair Met(O), can defend human lens cells against oxidative stress induced cell death. A key feature of oxidative stress is increased reactive oxygen species (ROS) in association with loss of mitochondrial function. Here, we sought to establish a potential role for MsrA in the accumulation of ROS in lens cells and the corresponding mitochondrial membrane potential in these cells. Targeted gene silencing was used to establish populations of lens cells expressing different levels of MsrA, and the mitochondrial membrane potential and ROS levels of these cell populations were monitored. Decreased MsrA levels were found to be associated with loss of cell viability, decreased mitochondrial membrane potential, and increased ROS levels in the absence of oxidative stress. These effects were augmented upon oxidative stress treatment. These results provide evidence that MsrA is a major determinant for accumulation of ROS in lens cells and that increased ROS levels in lens cells are associated with a corresponding decrease in mitochondrial membrane potential that is likely related to the requirement for MsrA in lens cell viability. PMID:16934804

  14. Different B-type methionine sulfoxide reductases in Chlamydomonas may protect the alga against high-light, sulfur-depletion, or oxidative stress.

    PubMed

    Zhao, Lei; Chen, Mei; Cheng, Dongmei; Yang, Haomeng; Sun, Yongle; Zhou, Heyi; Huang, Fang

    2013-11-01

    The genome of unicellular green alga Chlamydomonas reinhardtii contains four genes encoding B-type methionine sulfoxide reductases, MSRB1.1, MSRB1.2, MSRB2.1, and MSRB2.2, with functions largely unknown. To understand the cell defense system mediated by the methionine sulfoxide reductases in Chlamydomonas, we analyzed expression and physiological roles of the MSRBs under different abiotic stress conditions using immunoblotting and quantitative polymerase chain reaction (PCR) analyses. We showed that the MSRB2.2 protein was accumulated in cells treated with high light (1,300 µE/m² per s), whereas MSRB1.1 was accumulated in the cells under 1 mmol/L H₂O₂ treatment or sulfur depletion. We observed that the cells with the MSRB2.2 knockdown and overexpression displayed increased and decreased sensitivity to high light, respectively, based on in situ chlorophyll a fluorescence measures. We also observed that the cells with the MSRB1.1 knockdown and overexpression displayed decreased and increased tolerance to sulfur-depletion and oxidative stresses, respectively, based on growth and H₂-producing performance. The physiological implications revealed from the experimental data highlight the importance of MSRB2.2 and MSRB1.1 in protecting Chlamydomonas cells against adverse conditions such as high-light, sulfur-depletion, and oxidative stresses. PMID:24034412

  15. Synthesis and antibacterial activity of pyridinium-tailored 2,5-substituted-1,3,4-oxadiazole thioether/sulfoxide/sulfone derivatives.

    PubMed

    Wang, Pei-Yi; Zhou, Lei; Zhou, Jian; Wu, Zhi-Bing; Xue, Wei; Song, Bao-An; Yang, Song

    2016-02-15

    By introducing the pyridinium group into 2,5-substituted-1,3,4-oxadiazole, a series of pyridinium-tailored 2,5-substituted-1,3,4-oxadiazole thioether/sulfoxide/sulfone derivatives were obtained, and their antibacterial activities were evaluated via turbidimeter test in vitro. The bioassays reveal that most of the target compounds exhibit better inhibition activities against pathogen Xanthomonas oryzae pv. oryzae, Ralstonia solanacearum, and Xanthomonas axonopodis pv. citri than positive controls bismerthiazol (CK1) or thiodiazole copper (CK2). Among them, I-8, I-10, I-12, II-10, II-12, III-10, and III-12 exert excellent inhibition activities against the three pathogenic bacteria with the half-maximal effective concentration (EC50) values ranging from 0.54 to 12.14 μg/mL. Our results demonstrate that pyridinium-tailored 1,3,4-oxadiazole thioether/sulfoxide/sulfone derivatives can serve as potential alternative bactericides for the management of plant bacterial diseases. PMID:26810264

  16. Revisiting the Aqueous Solutions of Dimethyl Sulfoxide by Spectroscopy in the Mid- and Near-Infrared: Experiments and Car-Parrinello Simulations.

    PubMed

    Wallace, Victoria M; Dhumal, Nilesh R; Zehentbauer, Florian M; Kim, Hyung J; Kiefer, Johannes

    2015-11-19

    The infrared and near-infrared spectra of the aqueous solutions of dimethyl sulfoxide are revisited. Experimental and computational vibrational spectra are analyzed and compared. The latter are determined as the Fourier transformation of the velocity autocorrelation function of data obtained from Car-Parrinello molecular dynamics simulations. The experimental absorption spectra are deconvolved, and the excess spectra are determined. The two-dimensional excess contour plot provides a means of visualizing and identifying spectral regions and concentration ranges exhibiting nonideal behavior. In the binary mixtures, the analysis of the SO stretching band provides a semiquantitative picture of the formation and dissociation of hydrogen-bonded DMSO-water complexes. A maximum concentration of these clusters is found in the equimolar mixture. At high DMSO concentration, the formation of rather stable 3DMSO:1water complexes is suggested. The formation of 1DMSO:2water clusters, in which the water oxygen atoms interact with the sulfoxide methyl groups, is proposed as a possible reason for the marked depression of the freezing temperature at the eutectic point. PMID:26509778

  17. Characterization of the chemical reactivity and nephrotoxicity of N-acetyl-S-(1,2-dichlorovinyl)-L-cysteine sulfoxide, a potential reactive metabolite of trichloroethylene

    SciTech Connect

    Irving, Roy M.; Pinkerton, Marie E.; Elfarra, Adnan A.

    2013-02-15

    N-Acetyl-S-(1,2-dichlorovinyl)-L-cysteine (NA-DCVC) has been detected in the urine of humans exposed to trichloroethylene and its related sulfoxide, N-acetyl-S-(1,2-dichlorovinyl)-L-cysteine sulfoxide (NA-DCVCS), has been detected as hemoglobin adducts in blood of rats dosed with S-(1,2-dichlorovinyl)-L-cysteine (DCVC) or S-(1,2-dichlorovinyl)-L-cysteine sulfoxide (DCVCS). Because the in vivo nephrotoxicity of NA-DCVCS was unknown, in this study, male Sprague–Dawley rats were dosed (i.p.) with 230 μmol/kg b.w. NA-DCVCS or its potential precursors, DCVCS or NA-DCVC. At 24 h post treatment, rats given NA-DCVC or NA-DCVCS exhibited kidney lesions and effects on renal function distinct from those caused by DCVCS. NA-DCVC and NA-DCVCS primarily affected the cortico-medullary proximal tubules (S{sub 2}–S{sub 3} segments) while DCVCS primarily affected the outer cortical proximal tubules (S{sub 1}–S{sub 2} segments). When NA-DCVCS or DCVCS was incubated with GSH in phosphate buffer pH 7.4 at 37 °C, the corresponding glutathione conjugates were detected, but NA-DCVC was not reactive with GSH. Because NA-DCVCS exhibited a longer half-life than DCVCS and addition of rat liver cytosol enhanced GSH conjugate formation, catalysis of GSH conjugate formation by the liver could explain the lower toxicity of NA-DCVCS in comparison with DCVCS. Collectively, these results provide clear evidence that NA-DCVCS formation could play a significant role in DCVC, NA-DCVC, and trichloroethylene nephrotoxicity. They also suggest a role for hepatic metabolism in the mechanism of NA-DCVC nephrotoxicity. - Highlights: ► NA-DCVCS and NA-DCVC toxicity are distinct from DCVCS toxicity. ► NA-DCVCS readily reacts with GSH to form mono- and di-GSH conjugates. ► Liver glutathione S-transferases enhance NA-DCVCS GSH conjugate formation. ► Renal localization of lesions suggests a role for NA-DCVCS in TCE nephrotoxicity.

  18. Unified view of oxidative C-H bond cleavage and sulfoxidation by a nonheme iron(IV)-oxo complex via Lewis acid-promoted electron transfer.

    PubMed

    Park, Jiyun; Morimoto, Yuma; Lee, Yong-Min; Nam, Wonwoo; Fukuzumi, Shunichi

    2014-04-01

    Oxidative C-H bond cleavage of toluene derivatives and sulfoxidation of thioanisole derivatives by a nonheme iron(IV)-oxo complex, [(N4Py)Fe(IV)(O)](2+) (N4Py = N,N-bis(2-pyridylmethyl)-N-bis(2-pyridyl)methylamine), were remarkably enhanced by the presence of triflic acid (HOTf) and Sc(OTf)3 in acetonitrile at 298 K. All the logarithms of the observed second-order rate constants of both the oxidative C-H bond cleavage and sulfoxidation reactions exhibit remarkably unified correlations with the driving forces of proton-coupled electron transfer (PCET) and metal ion-coupled electron transfer (MCET) in light of the Marcus theory of electron transfer when the differences in the formation constants of precursor complexes between PCET and MCET were taken into account, respectively. Thus, the mechanisms of both the oxidative C-H bond cleavage of toluene derivatives and sulfoxidation of thioanisole derivatives by [(N4Py)Fe(IV)(O)](2+) in the presence of HOTf and Sc(OTf)3 have been unified as the rate-determining electron transfer, which is coupled with binding of [(N4Py)Fe(IV)(O)](2+) by proton (PCET) and Sc(OTf)3 (MCET). There was no deuterium kinetic isotope effect (KIE) on the oxidative C-H bond cleavage of toluene via the PCET pathway, whereas a large KIE value was observed with Sc(OTf)3, which exhibited no acceleration of the oxidative C-H bond cleavage of toluene. When HOTf was replaced by DOTf, an inverse KIE (0.4) was observed for PCET from both toluene and [Ru(II)(bpy)3](2+) (bpy =2,2'-bipyridine) to [(N4Py)Fe(IV)(O)](2+). The PCET and MCET reactivities of [(N4Py)Fe(IV)(O)](2+) with Brønsted acids and various metal triflates have also been unified as a single correlation with a quantitative measure of the Lewis acidity. PMID:24605985

  19. A highly conductive poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) film with the solvent bath treatment by dimethyl sulfoxide as cathode for polymer tantalum capacitor

    NASA Astrophysics Data System (ADS)

    Ma, Xiaopin; Wang, Xiuyu; Li, Mingxiu; Chen, Tongning; Zhang, Hao; Chen, Qiang; Ding, Bonan; Liu, Yanpeng

    2016-06-01

    The highly conductive poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) films were prepared on porous tantalum pentoxide surface as cathode for polymer tantalum capacitors (PTC). The electrical performances of PTC with PEDOT:PSS films as cathode were optimized by dimethyl sulfoxide (DMSO) bath treatment. With the DMSO-bath treatment of PTC, the equivalent series resistance (ESR) of PTC decreased from 25 mΩ to 9 mΩ. The ultralow ESR led to better capacitance-frequency performance. The device reliability investigation revealed the enhanced environmental stability of PTC. The enhanced performances were attributed to the conductivity improvement of PEDOT:PSS cathode films and the removal of excess PSS from PEDOT:PSS films.

  20. Different shapes of spherical vaterite by photo-induced cis?trans isomerization of an azobenzene-containing polymer in a mixture of dimethyl sulfoxide and water

    NASA Astrophysics Data System (ADS)

    Keum, Dong-Ki; Na, Hai-Sub; Naka, Kensuke; Chujo, Yoshiki

    2004-10-01

    We studied the crystallization of CaCO3 by the photoisomerization of azobenzene groups in poly[1-[4-[3-carboxy-4-hydroxyphenylazobenzenesulfonamido]-1,2-ethanediyl, sodium salt] (PAZO) in a mixture of dimethyl sulfoxide and water at 30 °C. The products were characterized by scanning electron microscopy (SEM), FT-IR, and powder X-ray diffraction (XRD) analysis. We observed that the different shapes of spherical vaterite particles were produced by the changes of configuration and polarity of the azobenzene groups in the polymer which resulted from photo-induced isomerization. The results indicate that the nucleation of primary particles of CaCO3 was inhibited by in situ photo-induced cis-trans isomerization of PAZO. Therefore, we suggest that the shapes of the spherical vaterite can be effectively modified by photoisomerization of the azobenzene groups in the polymer at the initial stage of CaCO3 crystallization.

  1. Rapid, covalent addition of phosphine to dithiolene in a molybdenum tris(dithiolene). A new structural model for dimethyl sulfoxide reductase.

    PubMed

    Nguyen, Neilson; Lough, Alan J; Fekl, Ulrich

    2012-06-18

    Triphenylphosphine (PPh(3)) rapidly and reversibly adds to the bdt ligand in the molybdenum tris(dithiolene) complex Mo(tfd)(2)(bdt) [tfd = S(2)C(2)(CF(3))(2); bdt = S(2)C(6)H(4)], turning chelating bdt into the monodentate zwitterionic ligand SC(6)H(4)SPPh(3). A second PPh(3) molecule fills the newly created open site in the crystallographically characterized product Mo(tfd)(2)(SC(6)H(4)SPPh(3))(PPh(3)), which is a structural model for dimethyl sulfoxide (DMSO) reductase. While the complex is only a precatalyst for reduction of DMSO by PPh(3) (the initially low catalytic rate increases with time), Mo(tfd)(2)(SMe(2))(2) was found to be catalytically active without an induction period. PMID:22646474

  2. Interaction of cyclodextrins with pyrene-modified polyacrylamide in a mixed solvent of water and dimethyl sulfoxide as studied by steady-state fluorescence

    PubMed Central

    Hashidzume, Akihito; Zheng, Yongtai

    2012-01-01

    Summary The interaction of β- and γ-cyclodextrins (β-CD and γ-CD, respectively) with polyacrylamide modified with pyrenyl (Py) residues (pAAmPy) was investigated in a mixed solvent of water and dimethyl sulfoxide (DMSO) by steady-state fluorescence. In the absence of CD, the fluorescence spectra indicated that the formation of Py dimers became less favorable with increasing volume fraction of DMSO (x DMSO). The fluorescence spectra at varying x DMSO and CD concentrations indicated that β-CD and γ-CD included monomeric and dimeric Py residues, respectively. Using the fluorescence spectra, equilibrium constants of the formation of Py dimers and the complexation of β-CD and γ-CD with Py residues were roughly estimated based on simplified equilibrium schemes. PMID:23019465

  3. Effect of ionic strength on the thermodynamic characteristics of complexation between Fe(III) ion and nicotinamide in water-ethanol and water-dimethyl sulfoxide mixtures

    NASA Astrophysics Data System (ADS)

    Gamov, G. A.; Grazhdan, K. V.; Gavrilova, M. A.; Dushina, S. V.; Sharnin, V. A.; Baranski, A.

    2013-06-01

    Solutions of iron(III) perchlorate in water, water-ethanol, and water-dimethyl sulfoxide solvents (x_{H_2 O} = 0.7 and 0.25 mole fractions) at ionic strength values I = 0.1, 0.25, and 0.5 are studied by IR spectroscopy. Analysis of the absorption bands of perchlorate ion shows that it does not participate in association processes. It is demonstrated that in the range of ionic strength values between 0 and 0.5 (NaClO4), it affects neither the results from potentiometric titration to determine the stability constants of the iron(III)-nicotinamide complex nor the thermal effects of complexation determined via direct calorimetry in a binary solvent containing 0.3 mole fractions (m.f.) of a non-aqueous component.

  4. Improved Zn/Zn(II) redox kinetics, reversibility and cyclability in 1-ethyl-3-methylimmidazolium dicyanamide with water and dimethyl sulfoxide added

    NASA Astrophysics Data System (ADS)

    Xu, M.; Ivey, D. G.; Qu, W.; Xie, Z.

    2014-04-01

    Diluents composed of H2O and dimethyl sulfoxide (DMSO) were added to 1-ethyl-3-methylimmidazolium dicyanamide (EMI-DCA), yielding an electrolyte system that is potentially applicable for Zn-air batteries. H2O is critical for enhancing both the electrolyte conductivity and Zn/Zn(II) redox kinetics, but impairs Zn/Zn(II) redox reversibility and cyclability. DMSO has the ability to stabilize the electrolyte from H2O decomposition and is beneficial for maintaining Zn/Zn(II) redox reversibility and cyclability. Improved Zn/Zn(II) redox kinetics and reversibility, together with good cyclability up to 200 cycles, was achieved in EMI-DCA + H2O + DMSO in a mole ratio of 1:1.1:2.3.

  5. 3-[1-(3-Hy­droxy­benz­yl)-1H-benzimid­azol-2-yl]phenol dimethyl sulfoxide monosolvate

    PubMed Central

    Quezada-Miriel, Magdalena; Avila-Sorrosa, Alcives; German-Acacio, Juan Manuel; Reyes-Martínez, Reyna; Morales-Morales, David

    2012-01-01

    Crystals of the title compound were obtained as a 1:1 dimethyl sulfoxide solvate, C20H16N2O2·C2H6O. The mol­ecular conformation of the organic mol­ecule is similar to that in the previously reported unsolvated structure [Eltayeb et al. (2009 ▶). Acta Cryst. E65, o1374–o1375]. Thus, the dihedral angles formed by the benzimidazole moiety with the two benzene rings are 57.54 (4) and 76.22 (5)°, and the dihedral angle between the benzene rings is 89.23 (5)°. In the crystal, a three-dimensional network features O—H⋯O, O—H⋯N and O—H⋯S hydrogen bonds, as well as C—H⋯O and C—H⋯π inter­actions. PMID:23125815

  6. Improved in situ saccharification of cellulose pretreated by dimethyl sulfoxide/ionic liquid using cellulase from a newly isolated Paenibacillus sp. LLZ1.

    PubMed

    Hu, Dongxue; Ju, Xin; Li, Liangzhi; Hu, Cuiying; Yan, Lishi; Wu, Tianyun; Fu, Jiaolong; Qin, Ming

    2016-02-01

    A cellulase producing strain was newly isolated from soil samples and identified as Paenibacillus sp. LLZ1. A novel aqueous-dimethyl sulfoxide (DMSO)/1-ethyl-3-methylimidazolium diethyl phosphate ([Emin]DEP)-cellulase system was designed and optimized. In the pretreatment, DMSO was found to be a low-cost substitute of up to 70% ionic liquid to enhance the cellulose dissolution. In the enzymatic saccharification, the optimum pH and temperature of the Paenibacillus sp. LLZ1 cellulase were identified as 6.0 and 40°C, respectively. Under the optimized reaction condition, the conversion of microcrystalline cellulose and bagasse cellulose increased by 39.3% and 37.6%, compared with unpretreated cellulose. Compared to current methods of saccharification, this new approach has several advantages including lower operating temperature, milder pH, and less usage of ionic liquid, indicating a marked progress in environmental friendly hydrolysis of biomass-based materials. PMID:26618784

  7. Density and viscosity of mixtures of dimethyl sulfoxide + methanol, + ethanol, + propan-1-ol, + propan-2-ol, + butan-1-ol, + 2-methylpropan-1-ol, and + 2-methylpropan-2-ol at 298.15 K and 303.15 K

    SciTech Connect

    Nikam, P.S.; Jadhav, M.C.; Hasan, M.

    1996-09-01

    Densities and viscosities have been measured for the binary mixtures of dimethyl sulfoxide + methanol, + ethanol, + propan-1-ol, + propan-2-ol, + butan-1-ol, + 2-methylpropan-1-ol, and + 2-methylpropan-2-ol at 298.15 K and 303.15 K. From these results, the excess molar volume (V{sup E}) and deviation in viscosity ({Delta}{eta}) have been computed. These properties are used to calculate regression coefficients of the Redlich-Kister equation.

  8. [1-tert-Butyl-3-(pyridin-2-ylmethyl-κN)imidazol-2-yl­idene-κC 1]carbonyl­dichlorido(dimethyl sulfoxide-κS)ruthenium(II)

    PubMed Central

    Cheng, Yong; Hua, Wen-Qian; Zhou, Ying-Hua

    2011-01-01

    In the title complex, [RuCl2(C13H17N3)(C2H6OS)(CO)], the coordination environment around the Ru atom is slightly distorted octa­hedral. The Cl atoms are mutually trans to the dimethyl sulfoxide ligand and the imidazole carbene C atom, respectively. The carbonyl ligand is located trans to the pyridine N atom. PMID:22219810

  9. Muscarinic antagonists with multiple stereocenters: Synthesis, affinity profile and functional activity of isomeric 1-methyl-2-(2,2-alkylaryl-1,3-oxathiolan-5-yl)pyrrolidine sulfoxide derivatives.

    PubMed

    Dei, Silvia; Bellucci, Cristina; Buccioni, Michela; Ferraroni, Marta; Guandalini, Luca; Manetti, Dina; Marucci, Gabriella; Matucci, Rosanna; Nesi, Marta; Romanelli, Maria Novella; Scapecchi, Serena; Teodori, Elisabetta

    2008-05-15

    Completing a long-lasting research on 1,3-oxathiolane muscarinic ligands, we have synthesized a set of isomeric 1-methyl-2-(2,2-alkylaryl-1,3-oxathiolan-5-yl)pyrrolidine 3-sulfoxide derivatives, containing three or four stereogenic centers. In general the compounds are very potent antagonists even if, unlike the corresponding agonists, they show modest subtype selectivity. PMID:18455407

  10. Design, Synthesis, Acaricidal/Insecticidal Activity, and Structure-Activity Relationship Studies of Novel Oxazolines Containing Sulfone/Sulfoxide Groups Based on the Sulfonylurea Receptor Protein-Binding Site.

    PubMed

    Yu, Xiuling; Liu, Yuxiu; Li, Yongqiang; Wang, Qingmin

    2016-04-20

    Enormous compounds containing sulfone/sulfoxide groups have been used in a variety of fields, especially in drug and pesticide design. To search for novel environmentally benign and ecologically safe pesticides with unique modes of action, a series of 2,4-diphenyl-1,3-oxazolines containing sulfone/sulfoxide groups as chitin synthesis inhibitors (CSIs) were designed and synthesized on the basis of the sulfonylurea receptor protein-binding site for CSIs. Their structures were characterized by (1)H and (13)C nuclear magnetic resonance and high-resolution mass spectrometry. The acaricidal and insecticidal activities of the new compounds were evaluated. It was found that most of the target compounds displayed wonderful acaricidal activities against spider mite (Tetranychus cinnabarinus) larvae and eggs. Especially compounds I-4, II-3, and II-4 displayed higher activities than commercial etoxazole at a concentration of 2.5 mg L(-1). Some target compounds exhibited insecticidal activities against lepidopteran pests. The present work demonstrated that these compounds containing sulfone/sulfoxide groups could be considered as potential candidates for the development of novel acaricides in the future. PMID:27046020

  11. Stimulation of ouabain binding to Na,K-ATPase in 40% dimethyl sulfoxide by a factor from Na,K-ATPase preparations.

    PubMed

    Fontes, C F; Lopes, F E; Scofano, H M; Barrabin, H; Norby, J G

    1999-06-15

    In 40% dimethyl sulfoxide (Me2SO) high-affinity ouabain (O) binding to Na,K-ATPase (E) is promoted by Mg2+ in the absence of inorganic phosphate (Pi) (Fontes et al., Biochim. Biophys. Acta 1104, 215-225, 1995). Furthermore, in Me2SO the EO complex reacts very slowly with Pi and this ouabain binding can therefore be measured by the degree of inhibition of rapid phosphoenzyme formation. Here we found that, unexpectedly, the ouabain binding decreased with the enzyme concentration in the Me2SO assay medium. We extracted the enzyme preparation with Me2SO or chloroform/methanol and demonstrated that the extracted (depleted) enzyme bound ouabain poorly. Addition of such extracts to assays with low enzyme concentration or depleted enzyme fully restored the high-affinity ouabain binding. Dialysis experiments indicated that the active principle had a molecular mass between 3.5 and 12 kDa. It was highly resistant to proteolysis. It was suggested that the active principle could either be a low-molecular-weight, proteolysis-resistant-peptide (e.g., a proteolipid) or a factor with a nonproteinaceous nature. A polyclonal antibody raised against the C-terminal 10 amino acids of the rat kidney gamma-subunit was able to recognize this low-molecular-weight peptide present in the extracts. The previously depleted enzyme displayed lower amounts of the gamma-proteolipid in comparison to the native untreated enzyme, as demonstrated by immunoreaction with the antibody. PMID:10356286

  12. Determination of dimethyl sulfoxide and dimethyl sulfone in urine by gas chromatography-mass spectrometry after preparation using 2,2-dimethoxypropane.

    PubMed

    Takeuchi, Akito; Yamamoto, Shinobu; Narai, Rie; Nishida, Manami; Yashiki, Mikio; Sakui, Norihiro; Namera, Akira

    2010-05-01

    A method for routinely determination of dimethyl sulfoxide (DMSO) and dimethyl sulfone (DMSO(2)) in human urine was developed using gas chromatography-mass spectrometry. The urine sample was treated with 2,2-dimethoxypropane (DMP) and hydrochloric acid for efficient removal of water, which causes degradation of the vacuum level in mass spectrometer and shortens the life-time of the column. Experimental DMP reaction parameters, such as hydrochloric acid concentration, DMP-urine ratio, reaction temperature and reaction time, were optimized for urine. Hexadeuterated DMSO was used as an internal standard. The recoveries of DMSO and DMSO(2) from urine were 97-104 and 98-116%, respectively. The calibration curves showed linearity in the range of 0.15-54.45 mg/L for DMSO and 0.19-50.10 mg/L for DMSO(2). The limits of detection of DMSO and DMSO(2) were 0.04 and 0.06 mg/L, respectively. The relative standard deviations of intra-day and inter-day were 0.2-3.4% for DMSO and 0.4-2.4% for DMSO(2). The proposed method may be useful for the biological monitoring of workers exposed to DMSO in their occupational environment. PMID:19688817

  13. Carbon nanotube (CNT) and nanofibrillated cellulose (NFC) reinforcement effect on thermoplastic polyurethane (TPU) scaffolds fabricated via phase separation using dimethyl sulfoxide (DMSO) as solvent.

    PubMed

    Mi, Hao-Yang; Jing, Xin; Salick, Max R; Cordie, Travis M; Turng, Lih-Sheng

    2016-09-01

    Although phase separation is a simple method of preparing tissue engineering scaffolds, it suffers from organic solvent residual in the scaffold. Searching for nontoxic solvents and developing effective solvent removal methods are current challenges in scaffold fabrication. In this study, thermoplastic polyurethane (TPU) scaffolds containing carbon nanotubes (CNTs) or nanofibrillated cellulose fibers (NFCs) were prepared using low toxicity dimethyl sulfoxide (DMSO) as a solvent. The effects of two solvent removal approaches on the final scaffold morphology were studied. The freeze drying method caused large pores, with small pores on the pore walls, which created connections between the pores. Meanwhile, the leaching and freeze drying method led to interconnected fine pores with smaller pore diameters. The nucleation effect of CNTs and the phase separation behavior of NFCs in the TPU solution resulted in significant differences in the microstructures of the resulting scaffolds. The mechanical performance of the nanocomposite scaffolds with different morphologies was investigated. Generally, the scaffolds with a fine pore structure showed higher compressive properties, and both the CNTs and NFCs improved the compressive properties of the scaffolds, with greater enhancement found in TPU/NFC nanocomposite scaffolds. In addition, all scaffolds showed good sustainability under cyclical load bearing, and the biocompatibility of the scaffolds was verified via 3T3 fibroblast cell culture. PMID:27266475

  14. Second-harmonic generation microscopy used to evaluate the effect of the dimethyl sulfoxide in the cryopreservation process in collagen fibers of differentiated chondrocytes

    NASA Astrophysics Data System (ADS)

    Andreoli-Risso, M. F.; Duarte, A. S. S.; Ribeiro, T. B.; Bordeaux-Rego, P.; Luzo, A.; Baratti, M. O.; Adur, J.; de Thomaz, A. A.; Pelegati, V. B.; Carvalho, H. F.; Cesar, C. L.; Kharmadayan, P.; Costa, F. F.; Olalla-Saad, S. T.

    2012-03-01

    Cartilaginous lesions are a significant public health problem and the use of adult stem cells represents a promising therapy for this condition. Cryopreservation confers many advantages for practitioners engaged in cell-based therapies. However, conventional slow freezing has always been associated with damage and mortality due to intracellular ice formation, cryoprotectant toxicity, and dehydration. The aim of this work is to observe the effect of the usual Dimethyl Sulfoxide (DMSO) cryopreservation process on the architecture of the collagen fiber network of chondrogenic cells from mesenchymal stem cells by Second Harmonic Generation (SHG) microscopy. To perform this study we used Mesenchymal Stem Cells (MSC) derived from adipose tissue which presents the capacity to differentiate into other lineages such as osteogenic, adipogenic and chondrogenic lineages. Mesenchymal stem cells obtained after liposuction were isolated digested by collagenase type I and characterization was carried out by differentiation of mesodermic lineages, and flow cytometry using specific markers. The isolated MSCs were cryopreserved by the DMSO technique and the chondrogenic differentiation was carried out using the micromass technique. We then compared the cryopreserved vs non-cryopreserved collagen fibers which are naturally formed during the differentiation process. We observed that noncryopreserved MSCs presented a directional trend in the collagen fibers formed which was absent in the cryopreserved MSCs. We confirmed this trend quantitatively by the aspect ratio obtained by Fast Fourier Transform which was 0.76 for cryopreserved and 0.52 for non-cryopreserved MSCs, a statistical significant difference.

  15. The use of tetrabutylammonium fluoride to promote N- and O-(11) C-methylation reactions with iodo[(11) C]methane in dimethyl sulfoxide.

    PubMed

    Kikuchi, Tatsuya; Minegishi, Katsuyuki; Hashimoto, Hiroki; Zhang, Ming-Rong; Kato, Koichi

    2013-11-01

    The N- or O-methylation reactions of compounds bearing amide, aniline, or phenol moieties using iodo[(11) C]methane (1) with the aid of a base are frequently applied to the preparation of (11) C-labeled radiopharmaceuticals. Although sodium hydride and alkaline metal hydroxides are commonly employed as bases in these reactions, their poor solubility properties in organic solvents and hydrolytic activities have sometimes limited their application and made the associated (11) C-methylation reactions difficult. In contrast to these bases, tetrabutylammonium fluoride (TBAF) is moderately basic, highly soluble in organic solvents, and weakly nucleophilic. Although it was envisaged that TBAF could be used as the preferred base for (11) C-methylation reactions using 1, studies concerning the use of TBAF to promote (11) C-methylation reactions are scarce. Herein, we have evaluated the efficiency of the (11) C-methylation reactions of 13 model compounds using TBAF and 1. In most cases, the N-(11) C-methylations were efficiently promoted by TBAF in dimethyl sulfoxide at ambient temperature, whereas the O-(11) C-methylations required heating in some cases. Comparison studies revealed that the efficiencies of the (11) C-methylation reactions with TBAF were comparable or sometimes greater than those conducted with sodium hydride. Based on these results, TBAF should be considered as the preferred base for (11) C-methylation reactions using 1. PMID:25196029

  16. Conversion of fructose and glucose into 5-hydroxymethylfurfural with lignin-derived carbonaceous catalyst under microwave irradiation in dimethyl sulfoxide-ionic liquid mixtures.

    PubMed

    Guo, Feng; Fang, Zhen; Zhou, Tie-Jun

    2012-05-01

    5-Hydroxymethylfurfural (5-HMF) was successfully produced by the dehydration of fructose and glucose using lignin-derived solid acid catalyst in DMSO-[BMIM][Cl] (dimethyl sulfoxide and 1-butyl-3-methylimidazolium chloride) mixtures. Six solid acid catalysts were synthesized by carbonization and sulfonation of raw biomass materials, i.e., glucose, fructose, cellulose, lignin, bamboo and Jatropha hulls. It was found that lignin-derived solid acid catalyst (LCC) was the most active one in the dehydration of sugars. LCC coupled with microwave irradiation was used for the 5-HMF production, 84% 5-HMF yield with 98% fructose conversion rate was achieved at 110°C for 10 min. Furthermore, 99% glucose was converted with 68% 5-HMF yield under severer condition (160°C for 50 min). LCC was recycled for five times, 5-HMF yield declined only 7%. Use of LCC combined with DMSO-[BMIM][Cl] solution and microwave irradiation is a novel method for the effective production of 5-HMF. PMID:22429401

  17. Water structure at aqueous solution surfaces of atmospherically relevant dimethyl sulfoxide and methanesulfonic acid revealed by phase-sensitive sum frequency spectroscopy.

    PubMed

    Chen, Xiangke; Allen, Heather C

    2010-11-25

    Interfacial water structures of aqueous dimethyl sulfoxide (DMSO) and methanesulfonic acid (MSA) were studied by Raman, infrared, and conventional and phase-sensitive vibrational sum frequency generation (VSFG) spectroscopies. Through isotopic dilution, we probed bulk water hydrogen bonding strength using the vibrational frequency of dilute OD in H(2)O. As indicated by the frequency shift of the OD frequency, it is shown that DMSO has little influence on the average water hydrogen bonding strength at low concentrations in contrast with an overall weakening effect for MSA. For the water structure at the surface of aqueous solutions, although conventional VSFG spectra suggest only slight structural changes with DMSO and a red shift of hydrogen-bonded water OH frequency, phase-sensitive VSFG reveals more thoroughly structural changes in the presence of both DMSO and MSA. In the case of DMSO, reorientation of interfacial water molecules with their hydrogens pointing up toward the oxygen of the S=O group is observed. For MSA, the interfacial water structure is affected by both the dissociated methanesulfonate anions and the hydronium ions residing at the surface. Both the methanesulfonate anions and the hydronium ions have surface preference; therefore, the electric double layer (EDL) formed at the surface is relatively thin, which leads to partial reorientation of interface water molecules with net orientation of water hydrogens up. Surface DMSO molecules are more effective at reorienting surface water relative to MSA molecules. PMID:21047087

  18. The minimal gene set member msrA, encoding peptide methionine sulfoxide reductase, is a virulence determinant of the plant pathogen Erwinia chrysanthemi.

    PubMed

    Hassouni, M E; Chambost, J P; Expert, D; Van Gijsegem, F; Barras, F

    1999-02-01

    Peptide methionine sulfoxide reductase (MsrA), which repairs oxidized proteins, is present in most living organisms, and the cognate structural gene belongs to the so-called minimum gene set [Mushegian, A. R. & Koonin, E. V., (1996) Proc. Natl. Acad. Sci. USA 93, 10268-10273]. In this work, we report that MsrA is required for full virulence of the plant pathogen Erwinia chrysanthemi. The following differences were observed between the wild-type and a MsrA- mutant: (i) the MsrA- mutant was more sensitive to oxidative stress; (ii) the MsrA- mutant was less motile on solid surface; (iii) the MsrA- mutant exhibited reduced virulence on chicory leaves; and (iv) no systemic invasion was observed when the MsrA- mutant was inoculated into whole Saintpaulia ionantha plants. These results suggest that plants respond to virulent pathogens by producing active oxygen species, and that enzymes repairing oxidative damage allow virulent pathogens to survive the host environment, thereby supporting the theory that active oxygen species play a key role in plant defense. PMID:9927663

  19. Determination of aldicarb, aldicarb sulfoxide and aldicarb sulfone in some fruits and vegetables using high-performance liquid chromatography-atmospheric pressure chemical ionization mass spectrometry.

    PubMed

    Nunes, G S; Alonso, R M; Ribeiro, M L; Barceló, D

    2000-08-01

    An analytical method for the determination of aldicarb, and its two major metabolites, aldicarb sulfoxide and aldicarb sulfone in fruits and vegetables is described. Briefly the method consisted of the use of a methanolic extraction, liquid-liquid extraction followed by solid-phase extraction clean-up. Afterwards, the final extract is analyzed by liquid chromatography-atmospheric pressure chemical ionization mass spectrometry (LC-APCI-MS). The specific fragment ion corresponding to [M-74]+ and the protonated molecular [M+H]+ ion were used for the unequivocal determination of aldicarb and its two major metabolites. The analytical performance of the proposed method and the results achieved were compared with those obtained using the common analytical method involving LC with post-column fluorescence detection (FL). The limits of detection varied between 0.2 and 1.3 ng but under LC-FL were slightly lower than when using LC-APCI-MS. However both methods permitted one to achieve the desired sensitivity for analyzing aldicarb and its metabolites in vegetables. The method developed in this work was applied to the trace determination of aldicarb and its metabolites in crop and orange extracts. PMID:10949478

  20. Carboxymethyl Cellulose (CMC) from Oil Palm Empty Fruit Bunch (OPEFB) in the new solvent Dimethyl Sulfoxide (DMSO)/Tetrabutylammonium Fluoride (TBAF)

    NASA Astrophysics Data System (ADS)

    Eliza, M. Y.; Shahruddin, M.; Noormaziah, J.; Rosli, W. D. Wan

    2015-06-01

    The surplus of Oil Palm is the most galore wastes in Malaysia because it produced about half of the world palm oil production, which contributes a major disposal problem Synthesis from an empty fruit bunch produced products such as Carboxymethyl Cellulose (CMC), could apply in diverse application such as for paper coating, food packaging and most recently, the potential as biomaterials has been revealed. In this study, CMC was prepared by firstly dissolved the bleached pulp from OPEFB in mixture solution of dimethyl sulfoxide(DMSO)/tetrabutylammonium fluoride (TBAF) without any prior chemical modification. It took only 30 minutes to fully dissolve at temperature 60°C before sodium hydroxide (NaOH) were added for activation and monochloroacetateas terrifying agent. The final product is appeared in white powder, which is then will be analyzedby FTIR analysis. FTIR results show peaks appeared at wavenumber between 1609 cm-1 to 1614 cm-1 proved the existence of carboxymethyl groups which substitute OH groups at anhydroglucose(AGU) unit. As a conclusion, mixture solution of DMSO/TBAF is the suitable solvent used for dissolved cellulose before modifying it into CMC with higher Degree of Substitution (DS). Furthermore, the dissolution of the OPEFB bleached pulp was easy, simple and at a faster rate without prior chemical modification at temperature as low as 60°C.

  1. Hydrogen bonding interactions between a representative pyridinium-based ionic liquid [BuPy][BF4] and water/dimethyl sulfoxide.

    PubMed

    Wang, Nan-Nan; Zhang, Qing-Guo; Wu, Fu-Gen; Li, Qing-Zhong; Yu, Zhi-Wu

    2010-07-01

    Infrared spectroscopy and density functional theory calculations have been applied to elucidate the hydrogen bonding interactions between water/dimethyl sulfoxide (DMSO) and a representative pyridinium-based ionic liquid, 1-butylpyridinium tetrafluoroborate ([BuPy][BF(4)]). It has been found that both solvents can interact with the BuPy(+) cation through the aromatic C-H. The strength of the H-bonds involving the aromatic C-H in water is similar to that in pure [BuPy][BF(4)], but is much stronger in DMSO. For DMSO, when it forms H-bonds with the BuPy(+) cation through its S=O group, its back-side methyl groups act as electron donors, while the butyl group of the cation acts as an electron acceptor. For water, when it forms the strong anion-HOH-anion complex, it can also form H-bonds with the aromatic C-H on the BuPy(+) cation. This is different from the imidazolium-based ionic liquid, where the strong anion-cation interaction and steric hindrance from the alkyls prevent water molecules from H-bonding with the aromatic C-H other than with the anion. PMID:20550148

  2. Increasing the energy density of the non-aqueous vanadium redox flow battery with the acetonitrile-1,3-dioxolane-dimethyl sulfoxide solvent mixture

    NASA Astrophysics Data System (ADS)

    Herr, T.; Fischer, P.; Tübke, J.; Pinkwart, K.; Elsner, P.

    2014-11-01

    Different solvent mixtures were investigated for non-aqueous vanadium acetylacetonate (V(acac)3) redox flow batteries with tetrabutylammonium hexafluorophosphate as the supporting electrolyte. The aim of this study was to increase the energy density of the non-aqueous redox flow battery. A mixture of acetonitrile, dimethyl sulfoxide and 1-3-dioxolane nearly doubles the solubility of the active species. The proposed electrolyte system was characterized by Raman and FT-IR spectroscopy, cyclic voltammetry, electrochemical impedance spectroscopy and charge-discharge set-up. Spectroscopic methods were applied to understand the interactions between the solvents used and their impact on the solubility. The potential difference between oxidation and reduction of V(acac)3 measured by cyclic voltammetry was about 2.2 V. Impedance spectroscopy showed an electrolyte resistance of about 2400 Ω cm2. Experiments in a charge-discharge test cell achieved coulombic and energy efficiencies of ∼95% and ∼27% respectively. The highest discharge power density was 0.25 mW cm-2.

  3. Dimethyl sulfoxide: an antagonist in scintillation proximity assay [(35)S]-GTPgammaS binding to rat 5-HT(6) receptor cloned in HEK-293 cells?

    PubMed

    Mereghetti, Ilario; Cagnotto, Alfredo; Mennini, Tiziana

    2007-03-15

    We have tested by [(35)S]-GTPgammaS binding the intrinsic activity of three full agonists (serotonin, 5-methoxytryptamine and 5-methoxy-2-methyl-N,N-dimethyltryptamine) on rat 5-HT(6) receptors cloned in HEK-293 cells, using the scintillation proximity assay. Serotonin and 5-methoxytryptamine are soluble in water, while the agonist 5-methoxy-2-methyl-N,N-dimethyltryptamine is soluble in dimethyl sulfoxide (DMSO). In [(35)S]-GTPgammaS binding 5-HT and 5-methoxytryptamine were able to increase basal binding, while 5-methoxy-2-methyl-N,N-dimethyltryptamine surprisingly showed an inverse agonist activity. So we have tested 5-HT and 5-methoxytryptamine in the presence of DMSO: in this condition the two agonists behaved as antagonists. This interfering effect of DMSO was not observed when GTP-europium filtration binding was used in place of scintillation proximity assay using [(35)S]-GTPgammaS. In addition, DMSO did not affect [(3)H]-5HT binding or cAMP accumulation in cloned HEK-293 cells expressing rat 5-HT(6) receptors. In conclusion, we demonstrated that DMSO, the most common solvent used to dissolve compounds insoluble in water, interferes with the method of scintillation proximity assay using [(35)S]-GTPgammaS. DMSO does not affect basal signal, nor the GTPgammaS binding itself, as indicated by the experiments with GTP-europium. Therefore its interfering effect is likely to occur at the binding of antibodies in the scintillation proximity assay. PMID:17049618

  4. Solution-processed poly(3,4-ethylenedioxythiophene) thin films as transparent conductors: effect of p-toluenesulfonic acid in dimethyl sulfoxide.

    PubMed

    Mukherjee, Smita; Singh, Rekha; Gopinathan, Sreelekha; Murugan, Sengottaiyan; Gawali, Suhas; Saha, Biswajit; Biswas, Jayeeta; Lodha, Saurabh; Kumar, Anil

    2014-10-22

    Conductivity enhancement of thin transparent films based on poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) (PEDOT-PSS) by a solution-processed route involving mixture of an organic acid and organic solvent is reported. The combined effect of p-toluenesulfonic acid and dimethyl sulfoxide on spin-coated films of PEDOT-PSS on glass substrates, prepared from its commercially available aqueous dispersion, was found to increase the conductivity of the PEDOT-PSS film to ∼3500 S·cm(-1) with a high transparency of at least 94%. Apart from conductivity and transparency measurements, the films were characterized by Raman, infrared, and X-ray photoelectron spectroscopy along with atomic force microscopy and secondary ion mass spectrometry. Combined results showed that the conductivity enhancement was due to doping, rearrangement of PEDOT particles owing to phase separation, and removal of PSS matrix throughout the depth of the film. The temperature dependence of the resistance for the treated films was found to be in accordance with one-dimensional variable range hopping, showing that treatment is effective in reducing energy barrier for interchain and interdomain charge hopping. Moreover, the treatment was found to be compatible with flexible poly(ethylene terephthalate) (PET) substrates as well. Apart from being potential candidates to replace inorganic transparent conducting oxide materials, the films exhibited stand-alone catalytic activity toward I(-)/I3(-) redox couple as well and successfully replaced platinum and fluorinated tin oxide as counter electrode in dye-sensitized solar cells. PMID:25230160

  5. Applicability of the DMSO (dimethyl sulfoxide) aggregate degradation test to determine moisture-induced distress in asphalt-concrete mixes. Final report, June 1986-June 1987

    SciTech Connect

    Heinicke, J.J.; Vinson, T.S.; Wilson, J.E.

    1987-06-01

    A laboratory investigation was conducted to evaluate the effectiveness of the dimethyl sulfoxide accelerated weathering test (DMSO test) to predict moisture-induced distress in asphalt-concrete mixtures. Asphalt-concrete specimens were fabricated using aggregates from three quarries. The specimens were conditioned using vacuum saturation and a series of five freeze/thaw cycles. The resilient modulus (M{sub r}) was obtained before and after each conditioning cycle and the Index of Retained Resilient Modulus (IRM{sub r}) was determined. The results indicate the DMSO test may be used to identify the potential for moisture-induced distress in asphalt-concrete mixtures. However, no correlation was determined between the DMSO test results and the IRM{sub r} or fatigue life test results. The strain and temperature dependencies of the M{sub r} were determined for a dense-graded asphalt-concrete mixture. It was concluded that constant stress testing may result in a misinterpretation of the IRM{sub r} and tests conducted within the currently accepted temperature range may result in a plus or minus 20% deviation in the IRM{sub r}. In an accompanying analytical program, the effect of diametral test boundary conditions on the measured value of M{sub r} was evaluated using two- and three-dimensional finite element models. The results indicate that the resilient modulus diametral test is adequately represented by elastic theory and an assumed plane stress condition.

  6. Methionine Sulfoxide Reductase A Negatively Controls Microglia-Mediated Neuroinflammation via Inhibiting ROS/MAPKs/NF-κB Signaling Pathways Through a Catalytic Antioxidant Function

    PubMed Central

    Fan, Hua; Wu, Peng-Fei; Zhang, Ling; Hu, Zhuang-Li; Wang, Wen; Guan, Xin-Lei; Luo, Han; Ni, Ming; Yang, Jing-Wen; Li, Ming-Xing

    2015-01-01

    Abstract Aims: Oxidative burst is one of the earliest biochemical events in the inflammatory activation of microglia. Here, we investigated the potential role of methionine sulfoxide reductase A (MsrA), a key antioxidant enzyme, in the control of microglia-mediated neuroinflammation. Results: MsrA was detected in rat microglia and its expression was upregulated on microglial activation. Silencing of MsrA exacerbated lipopolysaccharide (LPS)-induced activation of microglia and the production of inflammatory markers, indicating that MsrA may function as an endogenous protective mechanism for limiting uncontrolled neuroinflammation. Application of exogenous MsrA by transducing Tat-rMsrA fusion protein into microglia attenuated LPS-induced neuroinflammatory events, which was indicated by an increased Iba1 (a specific microglial marker) expression and the secretion of pro-inflammatory cytokines, and this attenuation was accompanied by inhibiting multiple signaling pathways such as p38 and ERK mitogen-activated protein kinases (MAPKs) and nuclear factor kappaB (NF-κB). These effects were due to MsrA-mediated reactive oxygen species (ROS) elimination, which may be derived from a catalytic effect of MsrA on the reaction of methionine with ROS. Furthermore, the transduction of Tat-rMsrA fusion protein suppressed the activation of microglia and the expression of pro-inflammatory factors in a rat model of neuroinflammation in vivo. Innovation: This study provides the first direct evidence for the biological significance of MsrA in microglia-mediated neuroinflammation. Conclusion: Our data provide a profound insight into the role of endogenous antioxidative defense systems such as MsrA in the control of microglial function. Antioxid. Redox Signal. 22, 832–847. PMID:25602783

  7. Solvation dynamics of tryptophan in water-dimethyl sulfoxide binary mixture: In search of molecular origin of composition dependent multiple anomalies

    NASA Astrophysics Data System (ADS)

    Roy, Susmita; Bagchi, Biman

    2013-07-01

    Experimental and simulation studies have uncovered at least two anomalous concentration regimes in water-dimethyl sulfoxide (DMSO) binary mixture whose precise origin has remained a subject of debate. In order to facilitate time domain experimental investigation of the dynamics of such binary mixtures, we explore strength or extent of influence of these anomalies in dipolar solvation dynamics by carrying out long molecular dynamics simulations over a wide range of DMSO concentration. The solvation time correlation function so calculated indeed displays strong composition dependent anomalies, reflected in pronounced non-exponential kinetics and non-monotonous composition dependence of the average solvation time constant. In particular, we find remarkable slow-down in the solvation dynamics around 10%-20% and 35%-50% mole percentage. We investigate microscopic origin of these two anomalies. The population distribution analyses of different structural morphology elucidate that these two slowing down are reflections of intriguing structural transformations in water-DMSO mixture. The structural transformations themselves can be explained in terms of a change in the relative coordination number of DMSO and water molecules, from 1DMSO:2H2O to 1H2O:1DMSO and 1H2O:2DMSO complex formation. Thus, while the emergence of first slow down (at 15% DMSO mole percentage) is due to the percolation among DMSO molecules supported by the water molecules (whose percolating network remains largely unaffected), the 2nd anomaly (centered on 40%-50%) is due to the formation of the network structure where the unit of 1DMSO:1H2O and 2DMSO:1H2O dominates to give rise to rich dynamical features. Through an analysis of partial solvation dynamics an interesting negative cross-correlation between water and DMSO is observed that makes an important contribution to relaxation at intermediate to longer times.

  8. Amino alcohol-derived reduced Schiff base V(IV)O and V(V) compounds as catalysts for asymmetric sulfoxidation of thioanisole with hydrogen peroxide.

    PubMed

    Adão, Pedro; Kuznetsov, Maxim L; Barroso, Sónia; Martins, Ana M; Avecilla, F; Costa Pessoa, João

    2012-11-01

    We report the synthesis and characterization of several amino alcohol-derived reduced Schiff base ligands (AORSB) and the corresponding V(IV)O and V(V) complexes. Some of the related Schiff base variants (amino alcohol derived Schiff base = AOSB) were also prepared and characterized. With some exceptions, all compounds are formulated as dinuclear compounds {V(IV)O(L)}(2) in the solid state. Suitable crystals for X-ray diffraction were obtained for two of the AORSB compounds, as well as a rare X-ray structure of a chiral V(IV)O compound, which revealed a dinuclear {V(IV)O(AOSB)}(2) structure with a rather short V-V distance of 3.053(9) Å. Electron paramagnetic resonance (EPR), (51)V NMR, and density functional theory (DFT) studies were carried out to identify the intervenient species prior to and during catalytic reactions. The quantum-chemical DFT calculations were important to determine the more stable isomers in solution, to explain the EPR data, and to assign the (51)V NMR chemical shifts. The V(AORSB) and V(AOSB) complexes were tested as catalysts in the oxidation of thioanisole, with H(2)O(2) as the oxidant in organic solvents. In general, high conversions of sulfoxide were obtained. The V(AOSB) systems exhibited greater activity and enantioselectivity than their V(AORSB) counterparts. Computational and spectroscopic studies were carried out to assist in the understanding of the mechanistic aspects and the reasons behind such marked differences in activity and enantioselectivity. The quantum-chemical calculations are consistent with experimental data in the assessment of the differences in catalytic activity between V(AOSB) and V(AORSB) peroxido variants because the V(AORSB) peroxido transition states correspond to ca. 22 kJ/mol higher energy activation barriers than their V(AOSB) counterparts. PMID:23092396

  9. Can ferric-superoxide act as a potential oxidant in P450(cam)? QM/MM investigation of hydroxylation, epoxidation, and sulfoxidation.

    PubMed

    Lai, Wenzhen; Shaik, Sason

    2011-04-13

    In view of recent reports of high reactivity of ferric-superoxide species in heme and nonheme systems (Morokuma et al. J. Am. Chem. Soc. 2010, 132, 11993-12005; Que et al. Inorg. Chem. 2010, 49, 3618-3628; Nam et al. J. Am. Chem. Soc. 2010, 132, 5958-5959; J. Am. Chem. Soc. 2010, 132, 10668-10670), we use herein combined quantum mechanics/molecular mechanics (QM/MM) methods to explore the potential reactivity of P450(cam) ferric-superoxide toward hydroxylation, epoxidation, and sulfoxidation. The calculations demonstrate that P450 ferric-superoxide is a sluggish oxidant compared with the high-valent oxoiron porphyrin cation-radical species. As such, unlike heme enzymes with a histidine axial ligand, the P450 superoxo species does not function as an oxidant in P450(cam). The origin of this different behavior of the superoxo species of P450 vis-à-vis other heme enzymes like tryptophan 2, 3-dioxygenase (TDO) is traced to the ability of the latter superoxo species to make a stronger FeOO-X (X = H,C) bond and to stabilize the corresponding bond-activation transition states by resonance with charge-transfer configurations. By contrast, the negatively charged thiolate ligand in the P450 superoxo species minimizes the mixing of charge transfer configurations in the transition state and raises the reaction barrier. However, as we demonstrate, an external electric field oriented along the Fe-O axis with a direction pointing from Fe toward O will quench Cpd I formation by slowing the reduction of ferric-superoxide and will simultaneously lower the barriers for oxidation by the latter species, thereby enabling observation of superoxo chemistry in P450. Other options for nascent superoxo reactivity in P450 are discussed. PMID:21413763

  10. Combination of retinoic acid, dimethyl sulfoxide and 5-azacytidine promotes cardiac differentiation of human fetal liver-derived mesenchymal stem cells.

    PubMed

    Deng, Fuxue; Lei, Han; Hu, Yunfeng; He, Linjing; Fu, Hang; Feng, Rui; Feng, Panpan; Huang, Wei; Wang, Xi; Chang, Jing

    2016-03-01

    There are controversial reports about cardiac differentiation potential of mesenchymal stem cells (MSCs), and there is still no well-defined protocol for the induction of cardiac differentiation. The effects of retinoic acid (RA) and dimethyl sulfoxide (DMSO) on the proliferation and differentiation of human fetal liver-derived MSCs (HFMSCs) as well as the pluripotent state induced by 5-azacytidine (5-aza) in vitro were investigated. MSCs were isolated from fetal livers and cultured in accordance with previous reports. Cells were plated and were treated for 24 h by the combination of 5-aza, RA and DMSO in different doses. Different culture conditions were tested in our study, including temperature, oxygen content and medium. Three weeks later, cells were harvested for the certification of cardiac differentiation as well as the pluripotency, which indicated by cardiac markers and Oct4. It was found that the cardiac differentiation was only induced when HFMSCs were treated in the following conditions: in high-dose combination (5-aza 50 μM + RA 10(-1) μM + DMSO 1 %) in cardiac differentiation medium at 37 °C and 20 % O2. The results of immunohistochemistry and quantitative RT-PCR showed that about 40 % of the cells positively expressed Nkx2.5, desmin and cardiac troponin I, as well as Oct4. No beating cells were observed during the period. The combined treatment with RA, DMSO and 5-aza in high-dose could promote HFMSCs to differentiate into cardiomyocyte-like cells and possibly through the change of their pluripotent state. PMID:26070350

  11. Cluster-continuum quasichemical theory calculation of the lithium ion solvation in water, acetonitrile and dimethyl sulfoxide: an absolute single-ion solvation free energy scale.

    PubMed

    Carvalho, Nathalia F; Pliego, Josefredo R

    2015-10-28

    Absolute single-ion solvation free energy is a very useful property for understanding solution phase chemistry. The real solvation free energy of an ion depends on its interaction with the solvent molecules and on the net potential inside the solute cavity. The tetraphenyl arsonium-tetraphenyl borate (TATB) assumption as well as the cluster-continuum quasichemical theory (CC-QCT) approach for Li(+) solvation allows access to a solvation scale excluding the net potential. We have determined this free energy scale investigating the solvation of the lithium ion in water (H2O), acetonitrile (CH3CN) and dimethyl sulfoxide (DMSO) solvents via the CC-QCT approach. Our calculations at the MP2 and MP4 levels with basis sets up to the QZVPP+diff quality, and including solvation of the clusters and solvent molecules by the dielectric continuum SMD method, predict the solvation free energy of Li(+) as -116.1, -120.6 and -123.6 kcal mol(-1) in H2O, CH3CN and DMSO solvents, respectively (1 mol L(-1) standard state). These values are compatible with the solvation free energy of the proton of -253.4, -253.2 and -261.1 kcal mol(-1) in H2O, CH3CN and DMSO solvents, respectively. Deviations from the experimental TATB scale are only 1.3 kcal mol(-1) in H2O and 1.8 kcal mol(-1) in DMSO solvents. However, in the case of CH3CN, the deviation reaches a value of 9.2 kcal mol(-1). The present study suggests that the experimental TATB scale is inconsistent for CH3CN. A total of 125 values of the solvation free energy of ions in these three solvents were obtained. These new data should be useful for the development of theoretical solvation models. PMID:26395146

  12. Analyses of Fruit Flies That Do Not Express Selenoproteins or Express the Mouse Selenoprotein, Methionine Sulfoxide Reductase B1, Reveal a Role of Selenoproteins in Stress Resistance*

    PubMed Central

    Shchedrina, Valentina A.; Kabil, Hadise; Vorbruggen, Gerd; Lee, Byung Cheon; Turanov, Anton A.; Hirosawa-Takamori, Mitsuko; Kim, Hwa-Young; Harshman, Lawrence G.; Hatfield, Dolph L.; Gladyshev, Vadim N.

    2011-01-01

    Selenoproteins are essential in vertebrates because of their crucial role in cellular redox homeostasis, but some invertebrates that lack selenoproteins have recently been identified. Genetic disruption of selenoprotein biosynthesis had no effect on lifespan and oxidative stress resistance of Drosophila melanogaster. In the current study, fruit flies with knock-out of the selenocysteine-specific elongation factor were metabolically labeled with 75Se; they did not incorporate selenium into proteins and had the same lifespan on a chemically defined diet with or without selenium supplementation. These flies were, however, more susceptible to starvation than controls, and this effect could be ascribed to the function of selenoprotein K. We further expressed mouse methionine sulfoxide reductase B1 (MsrB1), a selenoenzyme that catalyzes the reduction of oxidized methionine residues and has protein repair function, in the whole body or the nervous system of fruit flies. This exogenous selenoprotein could only be expressed when the Drosophila selenocysteine insertion sequence element was used, whereas the corresponding mouse element did not support selenoprotein synthesis. Ectopic expression of MsrB1 in the nervous system led to an increase in the resistance against oxidative stress and starvation, but did not affect lifespan and reproduction, whereas ubiquitous MsrB1 expression had no effect. Dietary selenium did not influence lifespan of MsrB1-expressing flies. Thus, in contrast to vertebrates, fruit flies preserve only three selenoproteins, which are not essential and play a role only under certain stress conditions, thereby limiting the use of the micronutrient selenium by these organisms. PMID:21622567

  13. A model for predicting the permeation of dimethyl sulfoxide into articular cartilage, and its application to the liquidus-tracking method.

    PubMed

    Yu, Xiaoyi; Chen, Guangming; Zhang, Shaozhi

    2013-12-01

    Long-term storage of articular cartilage (AC) has excited great interest due to the practical surgical significance of this tissue. The liquidus-tracking (LT) method developed by Pegg et al. (2006) [29] for vitreous preservation of AC achieved reasonable survival of post-warming chondrocytes in situ, but the design of the entire procedure was more dependent on trial and error. Mathematical modeling would help to better understand the LT process, and thereby make possible improvements to attain higher cell survival. Mass transfer plays a dominant role in the LT process. In the present study, a diffusion model based on the free-volume theory and the Flory-Huggins thermodynamics theory was developed to predict the permeation of dimethyl sulfoxide (Me2SO) into AC. A comparison between the predicted mean concentration of Me2SO in the AC disc and the experimental data over wide temperature and concentration ranges [-30 to 37 °C, 10 to 64.5% (w/w)] shows that the developed model can accurately describe the permeation of Me2SO into AC [coefficient of determination (R(2)): 0.951-1.000, mean relative error (MRE): 0.8-12.8%]. With this model, the spatial and temporal distribution of Me2SO in the AC disc during a loading/unloading process can be obtained. Application of the model to Pegg et al.'s LT procedure revealed that the liquidus line is virtually not followed for the center part of the AC disc. The presently developed model will be a useful tool in the analysis and design of the LT method for vitreous preservation of AC. PMID:24125912

  14. Dimethyl sulfoxide inhibits spontaneous diabetes and autoimmune recurrence in non-obese diabetic mice by inducing differentiation of regulatory T cells

    SciTech Connect

    Lin, Gu-Jiun; Sytwu, Huey-Kang; Yu, Jyh-Cherng; Chen, Yuan-Wu; Kuo, Yu-Liang; Yu, Chiao-Chi; Chang, Hao-Ming; Chan, De-Chuan; Huang, Shing-Hwa

    2015-01-15

    Type 1 diabetes mellitus (T1D) is caused by the destruction of insulin-producing β cells in pancreatic islets by autoimmune T cells. Islet transplantation has been established as an effective therapeutic strategy for T1D. However, the survival of islet grafts can be disrupted by recurrent autoimmunity. Dimethyl sulfoxide (DMSO) is a solvent for organic and inorganic substances and an organ-conserving agent used in solid organ transplantations. DMSO also exerts anti-inflammatory, reactive oxygen species scavenger and immunomodulatory effects and therefore exhibits therapeutic potential for the treatment of several human inflammatory diseases. In this study, we investigated the therapeutic potential of DMSO in the inhibition of autoimmunity. We treated an animal model of islet transplantation (NOD mice) with DMSO. The survival of the syngeneic islet grafts was significantly prolonged. The population numbers of CD8, DC and Th1 cells were decreased, and regulatory T (Treg) cell numbers were increased in recipients. The expression levels of IFN-γ and proliferation of T cells were also reduced following DMSO treatment. Furthermore, the differentiation of Treg cells from naive CD4 T cells was significantly increased in the in vitro study. Our results demonstrate for the first time that in vivo DMSO treatment suppresses spontaneous diabetes and autoimmune recurrence in NOD mice by inhibiting the Th1 immune response and inducing the differentiation of Treg cells. - Highlights: • We report a therapeutic potential of DMSO in autoimmune diabetes. • DMSO exhibits an immune modulatory effect. • DMSO treatment increases regulatory T cell differentiation. • The increase in STAT5 signaling pathway explains the effect of DMSO in Tregs.

  15. Dimethyl sulfoxide at 2.5% (v/v) alters the structural cooperativity and unfolding mechanism of dimeric bacterial NAD+ synthetase

    PubMed Central

    Yang, Zhengrong W.; Tendian, Susan W.; Carson, W. Michael; Brouillette, Wayne J.; Delucas, Lawrence J.; Brouillette, Christie G.

    2004-01-01

    Dimethyl sulfoxide (DMSO) is commonly used as a cosolvent to improve the aqueous solubility of small organic compounds. Its use in a screen to identify novel inhibitors of the enzyme NAD+ synthetase led to this investigation of its potential effects on the structure and stability of this 60-kD homodimeric enzyme. Although no effects are observed on the enzyme’s catalytic activity, as low as 2.5% (v/v) DMSO led to demonstrable changes in the stability of the dimer and its unfolding mechanism. In the absence of DMSO, the dimer behaves hydrodynamically as a single ideal species, as determined by equilibrium analytical ultracentrifugation, and thermally unfolds according to a two-state dissociative mechanism, based on analysis by differential scanning calorimetry (DSC). In the presence of 2.5% (v/v) DMSO, an equilibrium between the dimer and monomer is now detectable with a measured dimer association constant, Ka, equal to 5.6 × 106/M. DSC curve analysis is consistent with this finding. The data are best fit to a three-state sequential unfolding mechanism, most likely representing folded dimer ⇆ folded monomer ⇆ unfolded monomer. The unusually large change in the relative stabilities of dimer and monomer, e.g., the association equilibrium shifts from an infinitely large Ka down to ~106/M, in the presence of relatively low cosolvent concentration is surprising in view of the significant buried surface area at the dimer interface, roughly 20% of the surface area of each monomer is buried. A hypothetical structural mechanism to explain this effect is presented. PMID:14978314

  16. Dimethyl sulfoxide in a 10% concentration has no effect on oxidation stress induced by ovalbumin-sensitization in a guinea-pig model of allergic asthma.

    PubMed

    Mikolka, P; Mokra, D; Drgova, A; Petras, M; Mokry, J

    2012-04-01

    In allergic asthma, activated cells produce various substances including reactive oxygen species (ROS). As heterogenic pathophysiology of asthma results to different response to the therapy, testing novel interventions continues. Because of water-insolubility of some potentially beneficial drugs, dimethyl sulfoxide (DMSO) is often used as a solvent. Based on its antioxidant properties, this study evaluated effects of DMSO on mobilization of leukocytes into the lungs, and oxidation processes induced by ovalbumin (OVA)-sensitization in a guinea-pig model of allergic asthma. Guinea-pigs were divided into OVA-sensitized and naive animals. One group of OVA-sensitized animals and one group of naive animals were pretreated with 10% DMSO, the other two groups were given saline. After sacrificing animals, blood samples were taken and total antioxidant status (TAS) in the plasma was determined. Left lungs were saline-lavaged and differential leukocyte count in bronchoalveolar lavage fluid (BAL) was made. Right lung tissue was homogenized, TAS and products of lipid and protein oxidation were determined in the lung homogenate and in isolated mitochondria. OVA-sensitization increased total number of cells and percentages of eosinophils and neutrophils in BAL fluid; increased lipid and protein oxidation in the lung homogenate and mitochondria, and decreased TAS in the lungs and plasma compared with naive animals. However, no differences were observed in DMSO-instilled animals compared to controls. In conclusion, OVA-sensitization increased mobilization of leukocytes into the lungs and elevated production of ROS, accompanied by decrease in TAS. 10% DMSO had no effect on lipid and protein oxidation in a guinea-pig model of allergic asthma. PMID:22653905

  17. The sRNA RyhB Regulates the Synthesis of the Escherichia coli Methionine Sulfoxide Reductase MsrB but Not MsrA

    PubMed Central

    Bos, Julia; Duverger, Yohann; Thouvenot, Benoît; Chiaruttini, Claude; Branlant, Christiane; Springer, Mathias; Charpentier, Bruno; Barras, Frédéric

    2013-01-01

    Controlling iron homeostasis is crucial for all aerobically grown living cells that are exposed to oxidative damage by reactive oxygen species (ROS), as free iron increases the production of ROS. Methionine sulfoxide reductases (Msr) are key enzymes in repairing ROS-mediated damage to proteins, as they reduce oxidized methionine (MetSO) residues to methionine. E. coli synthesizes two Msr, A and B, which exhibit substrate diastereospecificity. The bacterial iron-responsive small RNA (sRNA) RyhB controls iron metabolism by modulating intracellular iron usage. We show in this paper that RyhB is a direct regulator of the msrB gene that encodes the MsrB enzyme. RyhB down-regulates msrB transcripts along with Hfq and RNaseE proteins since mutations in the ryhB, fur, hfq, or RNaseE-encoded genes resulted in iron-insensitive expression of msrB. Our results show that RyhB binds to two sequences within the short 5′UTR of msrB mRNA as identified by reverse transcriptase and RNase and lead (II) protection assays. Toeprinting analysis shows that RyhB pairing to msrB mRNA prevents efficient ribosome binding and thereby inhibits translation initiation. In vivo site directed-mutagenesis experiments in the msrB 5′UTR region indicate that both RyhB-pairing sites are required to decrease msrB expression. Thus, this study suggests a novel mechanism of translational regulation where a same sRNA can basepair to two different locations within the same mRNA species. In contrast, expression of msrA is not influenced by changes in iron levels. PMID:23671689

  18. The sRNA RyhB regulates the synthesis of the Escherichia coli methionine sulfoxide reductase MsrB but not MsrA.

    PubMed

    Bos, Julia; Duverger, Yohann; Thouvenot, Benoît; Chiaruttini, Claude; Branlant, Christiane; Springer, Mathias; Charpentier, Bruno; Barras, Frédéric

    2013-01-01

    Controlling iron homeostasis is crucial for all aerobically grown living cells that are exposed to oxidative damage by reactive oxygen species (ROS), as free iron increases the production of ROS. Methionine sulfoxide reductases (Msr) are key enzymes in repairing ROS-mediated damage to proteins, as they reduce oxidized methionine (MetSO) residues to methionine. E. coli synthesizes two Msr, A and B, which exhibit substrate diastereospecificity. The bacterial iron-responsive small RNA (sRNA) RyhB controls iron metabolism by modulating intracellular iron usage. We show in this paper that RyhB is a direct regulator of the msrB gene that encodes the MsrB enzyme. RyhB down-regulates msrB transcripts along with Hfq and RNaseE proteins since mutations in the ryhB, fur, hfq, or RNaseE-encoded genes resulted in iron-insensitive expression of msrB. Our results show that RyhB binds to two sequences within the short 5'UTR of msrB mRNA as identified by reverse transcriptase and RNase and lead (II) protection assays. Toeprinting analysis shows that RyhB pairing to msrB mRNA prevents efficient ribosome binding and thereby inhibits translation initiation. In vivo site directed-mutagenesis experiments in the msrB 5'UTR region indicate that both RyhB-pairing sites are required to decrease msrB expression. Thus, this study suggests a novel mechanism of translational regulation where a same sRNA can basepair to two different locations within the same mRNA species. In contrast, expression of msrA is not influenced by changes in iron levels. PMID:23671689

  19. On the Use of 3,5-Di-O-benzylidene and 3,5-Di-O-(di-tert-butylsilylene)-2-O-benzylarabinothiofuranosides and their Sulfoxides as Glycosyl Donors for the Synthesis of β-Arabinofuranosides: Importance of the Activation Method

    PubMed Central

    Crich, David; Pedersen, Christian Marcus; Bowers, Albert A.; Wink, Donald J.

    2008-01-01

    A 2-O-benzyl-3,5-di-O-benzylidene-α-d-thioarabinofuranoside was obtained by reaction of the corresponding diol with α,α-dibromotoluene under basic conditions. On activation with 1-benzenesulfinyl piperidine, or diphenyl sulfoxide, and trifluoromethanesulfonic anhydride in dichloromethane at −56 °C, reaction with glycosyl acceptors affords anomeric mixtures with little or no selectivity. The analogous 2-O-benzyl-3,5-di-O-(di-tert-butylsilylene)-α-d-thioarabinofuranoside also showed no significant selectivity under the 1-benzenesulfinyl piperidine or diphenyl sulfoxide conditions. With N-iodosuccinimide and silver trifluoromethanesulfonate the silylene acetal showed moderate to high β-selectivity, independent of the configuration of the starting thioglycoside. High β-selectivity was also obtained with a 2-O-benzyl-3,5-di-O-(di-tert-butylsilylene)-α-arabinofuranosyl sulfoxide donor on activation with trifluoromethanesulfonic anhydride. The high β-selectivities obtained by the N-iodosuccinimide/silver trifluoromethanesulfonate and sulfoxide methods are consistent with a common intermediate, most likely to be the oxacarbenium ion. The poor selectivity observed on activation of the thioglycosides with the 1-benzenesulfinyl piperidine, or diphenyl sulfoxide, and trifluoromethanesulfonic anhydride methods appears to be the result of the formation of a complex mixture of glycosyl donors, as determined by low temperature NMR work. PMID:17286432

  20. Carbonyl derivatives of chloride-dimethyl sulfoxide-ruthenium(III) complexes: Synthesis, crystal structure, and reactivity of [(DMSO){sub 2}H][trans-RuCl{sub 4}(DMSO)(CO)] and mer,cis-RuCl{sub 3}(DMSO){sub 2}(CO)

    SciTech Connect

    Alessio, E.; Bolle, M.; Milani, B.

    1995-09-13

    [(DMSO){sub 2}{sub 2}H][trans-RuCl{sub 4}(DMSO){sub 2}] (1) and mer,trans-RuCl{sub 3}(DMSO){sub 2}(DMSO) (2) (DMSO = S-bonded dimethyl sulfoxide; DMSO = O-bonded dimethyl sulfoxide; DMSO = O bonded dimethyl sulfoxide) react with carbon monoxide at room temperature and atmospheric pressure to give [(DMSO){sub 2}H][trans-RuCl{sub 4}(DMSO)(CO)] (3) and mer,cis-RuCl{sub 3}(DMSO){sub 2-} (CO) (4), respectively. Coordination of carbon monoxide induces the S to O linkage iosmerization of the DMSO ligand trans to it. Compounds 3 and 4 represent the first example of Ru-(III) chloride-DMSO-carbonyl complexes. In both 3 and 4 the DMSO ligand trans to CO is weakly bonded and easily replaced by a nitrogen donor ligand.

  1. Study of the Electrochemical System of Antimony-Tellurium in Dimethyl Sulfoxide for Growth of Nanowire Arrays, and an Innovative Method for Single Nanowire Measurements

    NASA Astrophysics Data System (ADS)

    Kalisman, Philip Taubman

    There is a strong interest in thermoelectric materials for energy production and savings. The properties which are integral to thermoelectric performance are typically linked, typically changing one of these properties for the better will change another for the worse. The intertwined nature of these properties has limited bulk thermoelectrics to low efficiencies, which has curbed their use to only niche applications. There has been theoretical and experimental work which has shown that limiting these materials in one or more dimensions will result in deconvolution of properties. Nanowires of well established thermoelectrics should show impressively high performance. Tellurium is attractive in many fields, including thermoelectrics. Nanowires of tellurium have been grown, but with limited success and with out the ability to dope the tellurium. Working on previous work with other systems, tellurium was studied in dimethyl sulfoxide (DMSO). The electrochemical system of tellurium was found to be quite dierent from its aqueous analog, but through comprehensive cyclic voltammetric study, all events were identified and explained. The binary antimony-tellurium system was also studied, as doping of tellurium is integral for many applications. Cyclic voltammograms of this system were studied, and the insight from these studies was used to grow nanowire arrays. Arrays of tellurium were grown and analysis showed that by using DMSO, antimony doped tellurium nanowire arrays could be grown. Furthermore, analysis showed that the antimony doped tellurium interstitially, resulting in a n-type material. Measurements were also performed on arrays and individual wires. Arrays of 1.15% antimony showed ZT of 0.092, with the low ZT attributed to poor contact methods. Although contacting was an obstacle towards measuring whole arrays, single wire measurements were also performed. Single wire measurements were done by a novel method which allows for easy, reproducible measurements of wire

  2. Impact of different green manures on the content of S-alk(en)yl-L-cysteine sulfoxides and L-ascorbic acid in leek (Allium porrum).

    PubMed

    Lundegårdh, B; Botek, P; Schulzov, V; Hajslov, J; Strömberg, A; Andersson, H C

    2008-03-26

    This field study investigated the impact of various fertilization strategies with red clover ( Trifolium pratense L.) green manure on the levels of S-alk(en)yl- l-cysteine sulfoxides (ACSO) and l-ascorbic acid in leek. Two of the 12 treatments were controls, one without fertilizers and the other with a commercial mineral fertilizer. The remaining 10 treatments were different forms and quantities of green manure prepared from red clover. One treatment consisted of direct incorporation into soil of the preceding red clover crop. The other 9 treatments comprised three types of red clover green manure [anaerobically digested red clover biomass (biodigestate), composted red clover, fresh red clover as mulch] applied at three different doses. Yield was increased only at the highest dose of compost and the highest dose of mulch. High doses of green manure decreased dry matter content in leek. The fertilizer treatments increased the nitrogen uptake and the nitrogen content of leek. Sulfur uptake and sulfur levels were increased only by the mineral fertilizer and by the compost. Nonfertilized leek contained 20.4 +/- 5.8 g/kg of dry weight (dw) ACSOs as determined by LC-MS/MS and 1.57 +/- 0.01 g/kg of dw ascorbic acid as determined by HPLC. The ACSOs were to 92-96% isoalliin, the rest being methiin. Alliin was identified in only 1 of 72 samples. The ACSO level was increased by 37% by the mineral fertilizer. Whereas direct incorporation of red clover, mulch, and red clover biodigestate had no influence on the ACSO level, the highest dose of compost increased the ACSO level by 55%. Ascorbic acid levels were not influenced by the mineral treatment. Green manures increased ascorbic acid levels only on a dry weight basis. A high correlation between the content of sulfur and ACSO indicated that delivering capacity of sulfur from the manure to the plant strongly affected the ASCO content of the leek. In conclusion, the composted green manure was the most useful organic fertilizer

  3. Methionine and methionine sulfoxide alter parameters of oxidative stress in the liver of young rats: in vitro and in vivo studies.

    PubMed

    Costa, Marcelo Zanusso; da Silva, Tatiane Morgana; Flores, Natália Porto; Schmitz, Felipe; da Silva Scherer, Emilene Barros; Viau, Cassiana Macagnan; Saffi, Jenifer; Barschak, Alethéa Gatto; de Souza Wyse, Angela Terezinha; Spanevello, Roselia Maria; Stefanello, Francieli Moro

    2013-12-01

    It has been shown that elevation of plasma methionine (Met) and its metabolites may occur in several genetic abnormalities. In this study we investigated the in vitro and in vivo effects of the Met and methionine sulfoxide (MetO) on oxidative stress parameters in the liver of rats. For in vitro studies, liver homogenates were incubated with Met, MetO, and Mix (Met + MetO). For in vivo studies, the animals were divided into groups: saline, Met 0.4 g/kg, MetO 0.1 g/kg, and Met 0.4 g/kg + MetO 0.1 g/kg. The animals were euthanized 1 and 3 h after injection. In vitro results showed that Met 1 and 2 mM and Mix increased catalase (CAT) activity. Superoxide dismutase (SOD) was enhanced by Met 1 and 2 mM, MetO 0.5 mM, and Mix. Dichlorofluorescein oxidation was increased by Met 1 mM and Mix. In vivo results showed that Met, MetO, and Mix decreased TBARS levels at 1 h. Total thiol content decreased 1 h after and increased 3 h after MetO and Met plus MetO administrations. Carbonyl content was enhanced by Met and was reduced by MetO 1 h after administration. Met, MetO and Met plus MetO decreased CAT activity 1 and 3 h after administration. Furthermore, only MetO increased SOD activity. In addition, Met, MetO, and Mix decreased dichlorofluorescein oxidation at 1 and 3 h. Our data indicate that Met/MetO in vivo and in vitro modify liver homeostasis by altering the redox cellular state. However, the hepatic changes caused by these compounds suggest a short-time adaptation of this tissue. PMID:23963990

  4. (2-{[4-(Chlorido­mercur­yl)phen­yl]imino­meth­yl}pyridine-κ2 N,N′)di­iodido­mercury(II) dimethyl sulfoxide monosolvate

    PubMed Central

    Basu Baul, Tushar S.; Longkumer, Imliwati; Ng, Seik Weng; Tiekink, Edward R. T.

    2013-01-01

    The title dimethyl sulfoxide solvate, [Hg2(C12H9ClN2)I2]·C2H6OS, features tetra­hedrally and linearly coordinated HgII atoms. The distorted tetrahedral coordination sphere is defined by chelating N atoms that define an acute angle [69.6 (3)°] and two I atoms that form a wide angle [142.80 (4)°]. The linearly coordinated HgII atom [177.0 (4)°] exists with a donor set defined by C and Cl atoms. Secondary inter­actions are apparent in the crystal packing with the tetra­hedrally and linearly coordinated HgII atoms expanding their coordination environments by forming weak Hg⋯I [3.772 (7) Å] and Hg⋯O [2.921 (12) Å] inter­actions, respectively. Mercury-containing mol­ecules stack along the a axis, are connected by π–π inter­actions [inter-centroid distance between pyridine and benzene rings = 3.772 (7) Å] and define channels in which the dimethyl sulfoxide mol­ecules reside. The latter are connected by the aforementioned Hg⋯O inter­actions as well as C—H⋯I and C—H⋯O inter­actions, resulting in a three-dimensional architecture. PMID:24454154

  5. Crystal structure of cis,fac-{N,N-bis-[(pyridin-2-yl)meth-yl]methyl-amine-κ(3) N,N',N''}di-chlorido-(dimethyl sulfoxide-κS)ruthenium(II).

    PubMed

    Trotter, Kasey; Arulsamy, Navamoney; Hulley, Elliott

    2015-09-01

    The reaction of di-chlorido-tetra-kis-(dimethyl sulfoxide)-ruthen-ium(II) with N,N-bis[(pyridin-2-yl)meth-yl]methyl-amine aff-ords the title complex, [RuCl2(C13H15N3)(C2H6OS)]. The asymmetric unit contains a well-ordered complex mol-ecule. The N,N-bis-[(pyridin-2-yl)meth-yl]methyl-amine (bpma) ligand binds the cation through its two pyridyl N atoms and one aliphatic N atom in a facial manner. The coordination sphere of the low-spin d (6) Ru(II) is distorted octahedral. The dimethyl sulfoxide (dmso) ligand coordinates to the cation through its S atom and is cis to the aliphatic N atom. The two chloride ligands occupy the remaining sites. The bpma ligand is folded with the dihedral angle between the mean planes passing through its two pyridine rings being 64.55 (8)°. The two N-Ru-N bite angles of the ligand at 81.70 (7) and 82.34 (8)° illustrate the distorted octa-hedral coordination geometry of the Ru(II) cation. Two neighboring molecules are weakly associated through mutual intermolecular hydrogen bonding involving the O atom and one of the methyl groups of the dmso ligand. One of the chloride ligands is also weakly hydrogen bonded to a pyridyl H atom of another molecule. PMID:26396870

  6. Functional and structural model for the molybdenum-pterin binding site in dimethyl sulfoxide reductase. Synthesis, crystal structure, and spectroscopic investigations of trichloro(quinonoid-N(8)H-6,7-dihydropterin)oxomolybdenum(IV)

    SciTech Connect

    Fischer, B.; Schmalle, H.; Dubler, E.

    1995-11-08

    Dimethyl sulfoxide is the substrate to the molybdenum-dependent enzyme dimethyl sulfoxide reductase, which is a member of the large group of molybdenum-containing non-nitrogenase redox enzymes. The active site of these enzymes is thought to possess a so-called molybdopterin, a hydrogenated pterin with an unusual side chain containing a dithiolene group. Up to now the enzyme reactivity was mostly attributed to molybdenum and to the coordination of these sulfur ligands in the side chain. The pterin moiety was not taken into account as playing an active part essential for the enzyme reaction. We demonstrated for the first time a possible coordination of a hydrogenated pterin to molybdenum with a complex of quinonoid-dihydro-L-biopterin bound to molybdenum in the oxidation state + IV. Now we report the synthesis, crystal structure, and spectroscopic data for trichloro-(quinonoid-N(8)H-6,7-dihydropterin)oxomolybdenum(IV), [MoOCl{sub 3}(H{sup +}-q-H{sub 2}Ptr)](1) (dihydropterin = H{sub 2}Ptr). Crystal data: a = 9.966(3) {angstrom}, b = 14.408(4) {angstrom}, c = 17.362(5) {angstrom}, V = 2493(2) {angstrom}{sup 3}, Z = 8, orthohombic, space group Pbca, R{sub 1} = 0.059 and wR{sub 2} = 0.0150. 1 is synthesized in a redox reaction between Mo(VI)O{sub 2}Cl{sub 2} and tetrahydropterin [H{sub 4}Ptr{center_dot}2HCl] and contains a cationic quinonoid dihydropterin coordinated via the N(5) and O(4) atoms to the molybdenum atom. The crystal structure of 1 containing the hydrogenated pterin exhibits an unusually short Mo-N(5) bond length of 2.013(3) {angstrom}, as compared to 2.324(6) {angstrom} for the corresponding bond in oxidized pterin. 1 is able to quantitatively reduce the substrate dimethyl sulfoxide to dimethyl sulfide under the strict exclusion of oxygen. This reaction can be monitored by {sup 13}C-NMR spectroscopy. A simplified in vivo reaction cycle for the enzyme center of DMSO reductase is proposed as a working hypothesis.

  7. Crystal structure of di-aqua-bis-(7-di-ethyl-amino-3-formyl-2-oxo-2H-chromen-4-olato-κ(2) O (3),O (4))zinc(II) dimethyl sulfoxide disolvate.

    PubMed

    Davis, Aaron B; Fronczek, Frank R; Wallace, Karl J

    2016-07-01

    The structure of the title coordination complex, [Zn(C14H14NO4)2(H2O)2]·2C2H6OS, shows that the Zn(II) cation adopts an octa-hedral geometry and lies on an inversion center. Two organic ligands occupy the equatorial positions of the coordination sphere, forming a chelate ring motif via the O atom on the formyl group and another O atom of the carbonyl group (a pseudo-β-diketone motif). Two water mol-ecules occupy the remaining coordination sites of the Zn(II) cation in the axial positions. The water mol-ecules are each hydrogen bonded to a single dimethyl sulfoxide mol-ecule that has been entrapped in the crystal lattice. PMID:27555957

  8. Crystal structure of di­aqua­bis­(7-di­ethyl­amino-3-formyl-2-oxo-2H-chromen-4-olato-κ2 O 3,O 4)zinc(II) dimethyl sulfoxide disolvate

    PubMed Central

    Davis, Aaron B.; Fronczek, Frank R.; Wallace, Karl J.

    2016-01-01

    The structure of the title coordination complex, [Zn(C14H14NO4)2(H2O)2]·2C2H6OS, shows that the ZnII cation adopts an octa­hedral geometry and lies on an inversion center. Two organic ligands occupy the equatorial positions of the coordination sphere, forming a chelate ring motif via the O atom on the formyl group and another O atom of the carbonyl group (a pseudo-β-diketone motif). Two water mol­ecules occupy the remaining coordination sites of the ZnII cation in the axial positions. The water mol­ecules are each hydrogen bonded to a single dimethyl sulfoxide mol­ecule that has been entrapped in the crystal lattice. PMID:27555957

  9. Crystal structure of cis,fac-{N,N-bis­[(pyridin-2-yl)meth­yl]methyl­amine-κ3 N,N′,N′′}di­chlorido­(dimethyl sulfoxide-κS)ruthenium(II)

    PubMed Central

    Trotter, Kasey; Arulsamy, Navamoney; Hulley, Elliott

    2015-01-01

    The reaction of di­chlorido­tetra­kis­(dimethyl sulfoxide)­ruthen­ium(II) with N,N-bis[(pyridin-2-yl)meth­yl]methyl­amine aff­ords the title complex, [RuCl2(C13H15N3)(C2H6OS)]. The asymmetric unit contains a well-ordered complex mol­ecule. The N,N-bis­[(pyridin-2-yl)meth­yl]methyl­amine (bpma) ligand binds the cation through its two pyridyl N atoms and one aliphatic N atom in a facial manner. The coordination sphere of the low-spin d 6 RuII is distorted octahedral. The dimethyl sulfoxide (dmso) ligand coordinates to the cation through its S atom and is cis to the aliphatic N atom. The two chloride ligands occupy the remaining sites. The bpma ligand is folded with the dihedral angle between the mean planes passing through its two pyridine rings being 64.55 (8)°. The two N—Ru—N bite angles of the ligand at 81.70 (7) and 82.34 (8)° illustrate the distorted octa­hedral coordination geometry of the RuII cation. Two neighboring molecules are weakly associated through mutual intermolecular hydrogen bonding involving the O atom and one of the methyl groups of the dmso ligand. One of the chloride ligands is also weakly hydrogen bonded to a pyridyl H atom of another molecule. PMID:26396870

  10. Crystal structure of bis­[N-phenyl-2-(1,2,3,4-tetrahydronaphthalen-1-ylidene)hydrazinecarbothio­amidato-κ2 N 2,S]zinc dimethyl sulfoxide monosolvate

    PubMed Central

    Cruz Santana, Genelane; Gimenez, Iara de Fátima; Näther, Christian; Jess, Inke; de Oliveira, Adriano Bof

    2015-01-01

    The reaction of the N-phenyl-2-(1,2,3,4-tetrahydronaphthalen-1-yl­idene)hy­dra­zine­car­bo­thio­amide ligand with zinc acetate dihydrate in a 2:1 molar ratio yielded a yellow solid, which was crystallized from DMSO to obtain the title compound, [Zn(C17H16N3S)2]·C2H6OS. The ZnII ion is four-coordinated in a distorted tetra­hedral environment by two deprotonated ligands. Each ligand acts as an N,S-donor, forming a five-membered metallacycle. The maximum deviation from the mean plane of the N–N–C–S chelate group is 0.0029 (14) Å for the N-donor atom of one ligand and 0.0044 (14) Å for the non-coordinating N atom of the second. The dihedral angle between the planes of the two chelate groups is 72.80 (07)°. Bond lengths in the ligands are compared with those in the crystal structure of the free ligand. In the crystal, complex mol­ecules are connected by dimethyl sulfoxide solvate mol­ecules via N—H⋯O hydrogen-bonding inter­actions, building a one-dimensional hydrogen-bonded polymer along the a-axis direction. The S atom and one C atom of the dimethyl sulfoxide solvate mol­ecules are disordered over two sets of sites with an occupancy ratio of 0.6:0.4. PMID:25995850

  11. Crystal structure of a one-dimensional helical-type silver(I) coordination polymer: catena-poly[[silver(I)-μ-N-(pyridin-4-ylmeth-yl)pyridine-3-amine-κ(2) N:N'] nitrate dimethyl sulfoxide disolvate].

    PubMed

    Moon, Bokhee; Jeon, Youngeun; Moon, Suk-Hee; Park, Ki-Min

    2014-12-01

    The asymmetric unit of the title compound, {[Ag(C11H11N3)]NO3·2(CH3)2SO} n , comprises one Ag(I) atom, one N-(pyridine-4-ylmeth-yl)pyridine-3-amine ligand, one nitrate anion and two dimethyl sulfoxide mol-ecules. The Ag(I) atoms are bridged by two pyridine N atoms from two symmetry-related ligands, forming a helical chain and adopting a slightly distorted linear coordination geometry [N-Ag-N = 175.37 (8)°]. The helical chain, with a pitch length of 16.7871 (8) Å, propagates along the b-axis direction. In the crystal, symmetry-related right- and left-handed helical chains are alternately arranged via Ag⋯Ag inter-actions [3.4145 (4) Å] and π-π stacking inter-actions [centroid-centroid distance = 3.650 (2) Å], resulting in the formation of a two-dimensional supra-molecular network extending parallel to (100). Weak Ag⋯O [2.775 (2), 3.169 (4) and 2.690 (2) Å] inter-actions, as well as several N-H⋯O and C-H⋯O hydrogen-bonding inter-actions, contribute to the stabilization of the crystal structure. Parts of the dimethyl sulfoxide solvent molecule are disordered over two sets of sites in a 0.937 (3):0.063 (3) ratio. PMID:25552978

  12. A simple assay for the simultaneous determination of human plasma albendazole and albendazole sulfoxide levels by high performance liquid chromatography in tandem mass spectrometry with solid-phase extraction.

    PubMed

    Wojnicz, Aneta; Cabaleiro-Ocampo, Teresa; Román-Martínez, Manuel; Ochoa-Mazarro, Dolores; Abad-Santos, Francisco; Ruiz-Nuño, Ana

    2013-11-15

    A simple, reproducible and fast (4 min chromatogram) method of liquid chromatography in tandem with mass spectrometry (LC/MS-MS) was developed to determine simultaneously the plasma levels of albendazole (ABZ) and its metabolite albendazole sulfoxide (ABZOX) for pharmacokinetic and clinical analysis. Each plasma sample was extracted by solid phase extraction (SPE) using phenacetin as internal standard (IS). The extracted sample was eluted with a Zorbax XDB-CN column using an isocratic method. The mobile phase consisting of water with 1% acetic acid (40%, A) and MeOH (60%, B), was used at a flow rate of 1 mL/min. ABZ and ABZOX were detected and identified by mass spectrometry with electrospray ionization (ESI) in the positive ion and multiple-reaction monitoring (MRM) mode. The method was linear in the range of 5-1000 ng/mL for ABZ and 10-1500 ng/mL (full validation) or 10-5000 ng/mL (partial validation) for ABZOX, with 5 and 10 ng/mL lower limit of quantification (LLOQ) for ABZ and ABZOX, respectively. The tests of accuracy and precision, matrix effect, extraction recovery and stability of the samples for both ABZ and ABZOX did not deviate more than 20% for the LLOQ and no more than 15% for other quality controls (QCs), according to regulatory agencies. PMID:24008168

  13. Co-cultures of human coronary smooth muscle cells and dimethyl sulfoxide-differentiated HL60 cells upregulate ProMMP9 activity and promote mobility-modulation by reactive oxygen species.

    PubMed

    Bernard, Yohann; Melchior, Chantal; Tschirhart, Eric; Bueb, Jean-Luc

    2008-10-01

    Vascular cells and leukocytes, involved in the development of atherosclerosis, produce cytokines and/or reactive oxygen species (ROS) and matrix metalloproteinases (MMPs) implicated in cell mobility. We investigated by co-culture experiments the effects of human coronary smooth muscle cells (HCSMC) on MMPs characteristics and mobility of neutrophil-like dimethyl sulfoxide-differentiated HL60 cells (not equal HL60). The effects of superoxide dismutase (SOD) and catalase were also analyzed. All the studied MMP2 characteristics remained unchanged. HCSMC stimulated MMP9 protein level, activity and mobility of not equal HL60 cells and expressed and secreted a variety of cytokines implicated in atherosclerosis. SOD and catalase increased MMP9 expression, protein level and activity of not equal HL60, but migration of not equal HL60 cells was only decreased by catalase, demonstrating that ROS are more efficient in modulating MMP9 activity of not equal HL60 than their mobility. Finally, HCSMC being able to stimulate not equal HL60, their co-cultures may represent an in vitro approach to study cellular interactions occurring in vivo during atherosclerosis. PMID:18665441

  14. New polar constituents of the pupae of the silkworm Bombyx mori L. I. Isolation and identification of methionine sulfoxide, methionine sulfone, and gamma-cyclic di-L-glutamate.

    PubMed

    Tanaka, Ryuichiro

    2007-12-01

    In addition to serine (L:D = 68:32), methionine sulfoxide (MSO), L-methionine sulfone (L-MSO(2)), and disodium gamma-cyclic di-L-glutamate were identified in a methanol extract of Bombyx mori L. pupae. MSO was isolated in a diastereomeric mixture of L(+)- and D(+)-MSO in a ratio of 99:1. The presence of these compounds in other developmental stages, including eggs, larvae (1st, 4th, 5th, and mature 5th instar), adults, and excrement (feces and urine) was investigated. The L(+)-isomer of MSO was present in extracts of the 1st and 5th instar larvae, adults, and eggs, but was not detected in feces or urine. The D(+)-isomer was found only in pupal stage extracts, and was excreted into the meconium with L(+)-isomer. L-MSO(2) and gamma-cyclic di-L-glutamate were not detected at other insect life stages or in the insect excrement. gamma-Cyclic di-L-glutamate is thought be produced due to blockage of the glutamate synthetic pathway (glutamine synthetase) by L-MSO(2) and Mg(2+). The biochemical role of L-MSO(2) during the pupal life stage remains unknown, but importantly, the stage-specific expression suggests that it is a candidate molecule for the induction of diapause. PMID:18071251

  15. Solute-solvent interactions in 2,4-dihydroxyacetophenone isonicotinoylhydrazone solutions in N, N-dimethylformamide and dimethyl sulfoxide at 298-313 K on ultrasonic and viscometric data

    NASA Astrophysics Data System (ADS)

    Dikkar, A. B.; Pethe, G. B.; Aswar, A. S.

    2016-02-01

    The speed of sound ( u), density (ρ), and viscosity (η) of 2,4-dihydroxyacetophenone isonicotinoylhydrazone (DHAIH) have been measured in N, N-dimethyl formamide and dimethyl sulfoxide at equidistance temperatures 298.15, 303.15, 308.15, and 313.15 K. These data were used to calculate some important ultrasonic and thermodynamic parameters such as apparent molar volume ( V ϕ s st ), apparent molar compressibility ( K ϕ), partial molar volume ( V ϕ 0 ) and partial molar compressibility ( K ϕ 0 ), were estimated by using the values of ( V ϕ 0 ) and ( K ϕ), at infinite dilution. Partial molar expansion at infinite dilution, (ϕ E 0 ) has also been calculated from temperature dependence of partial molar volume V ϕ 0 . The viscosity data have been analyzed using the Jones-Dole equation, and the viscosity, B coefficients are calculated. The activation free energy has been calculated from B coefficients and partial molar volume data. The results have been discussed in the term of solute-solvent interaction occurring in solutions and it was found that DHAIH acts as a structure maker in present systems.

  16. Nuclear magnetic resonance study of the kinetics of ligand-exchange reactions in uranyl complexes. Part 5. Exchange reaction of acetylacetonate in bis(acetylacetonato)(dimethyl sulfoxide)dioxouranium(VI)

    SciTech Connect

    Ikeda, Y.; Tomiyasu, H.; Fukutomi, H.

    1984-09-26

    The kinetics of the exchange reaction of acac in UO/sub 2/(acac)/sub 2/Me/sub 2/SO (acac = acetylacetonate, Me/sub 2/SO = dimethyl sulfoxide) has been studied in o-C/sub 6/H/sub 4/Cl/sub 2/ by means of /sup 1/H NMR. The exchange rate depends on the concentration of the enol isomer of acetylacetone in its low region and approaches to the limiting value in its high region. The rate-determining step seems to be ring opening for one of two coordinated acac ions. The kinetic parameters of this step at 25/sup 0/C were found to be: equilibrium constant = 2.04 sec/sup -1/, enthalpy = 66.4 +/- 8.4 kJ mol/sup -1/, and entropy = 17.1 +/- 28.6 J K/sup -1/ mol/sup -1/. It was found that the exchange rate is decreased by addition of free Me/sub 2/SO. This is explained by considering the competition of Me/sub 2/SO with the enol isomer in attacking the four-coordinated intermediate in the equatorial plane or the outer-sphere complex formation between UO/sub 2/(acac)/sub 2/Me/sub 2/SO and free Me/sub 2/SO.

  17. A Glycine soja methionine sulfoxide reductase B5a interacts with the Ca(2+) /CAM-binding kinase GsCBRLK and activates ROS signaling under carbonate alkaline stress.

    PubMed

    Sun, Xiaoli; Sun, Mingzhe; Jia, Bowei; Qin, Zhiwei; Yang, Kejun; Chen, Chao; Yu, Qingyue; Zhu, Yanming

    2016-06-01

    Although research has extensively illustrated the molecular basis of plant responses to salt and high-pH stresses, knowledge on carbonate alkaline stress is poor and the specific responsive mechanism remains elusive. We have previously characterized a Glycine soja Ca(2+) /CAM-dependent kinase GsCBRLK that could increase salt tolerance. Here, we characterize a methionine sulfoxide reductase (MSR) B protein GsMSRB5a as a GsCBRLK interactor by using Y2H and BiFc assays. Further analyses showed that the N-terminal variable domain of GsCBRLK contributed to the GsMSRB5a interaction. Y2H assays also revealed the interaction specificity of GsCBRLK with the wild soybean MSRB subfamily proteins, and determined that the BoxI/BoxII-containing regions within GsMSRBs were responsible for their interaction. Furthermore, we also illustrated that the N-terminal basic regions in GsMSRBs functioned as transit peptides, which targeted themselves into chloroplasts and thereby prevented their interaction with GsCBRLK. Nevertheless, deletion of these regions allowed them to localize on the plasma membrane (PM) and interact with GsCBRLK. In addition, we also showed that GsMSRB5a and GsCBRLK displayed overlapping tissue expression specificity and coincident expression patterns under carbonate alkaline stress. Phenotypic experiments demonstrated that GsMSRB5a and GsCBRLK overexpression in Arabidopsis enhanced carbonate alkaline stress tolerance. Further investigations elucidated that GsMSRB5a and GsCBRLK inhibited reactive oxygen species (ROS) accumulation by modifying the expression of ROS signaling, biosynthesis and scavenging genes. Summarily, our results demonstrated that GsCBRLK and GsMSRB5a interacted with each other, and activated ROS signaling under carbonate alkaline stress. PMID:27121031

  18. Flexibility at a glycosidic linkage revealed by molecular dynamics, stochastic modeling, and (13)C NMR spin relaxation: conformational preferences of α-L-Rhap-α-(1 → 2)-α-L-Rhap-OMe in water and dimethyl sulfoxide solutions.

    PubMed

    Pendrill, Robert; Engström, Olof; Volpato, Andrea; Zerbetto, Mirco; Polimeno, Antonino; Widmalm, Göran

    2016-01-28

    The monosaccharide L-rhamnose is common in bacterial polysaccharides and the disaccharide α-L-Rhap-α-(1 → 2)-α-L-Rhap-OMe represents a structural model for a part of Shigella flexneri O-antigen polysaccharides. Utilization of [1'-(13)C]-site-specific labeling in the anomeric position at the glycosidic linkage between the two sugar residues facilitated the determination of transglycosidic NMR (3)JCH and (3)JCC coupling constants. Based on these spin-spin couplings the major state and the conformational distribution could be determined with respect to the ψ torsion angle, which changed between water and dimethyl sulfoxide (DMSO) as solvents, a finding mirrored by molecular dynamics (MD) simulations with explicit solvent molecules. The (13)C NMR spin relaxation parameters T1, T2, and heteronuclear NOE of the probe were measured for the disaccharide in DMSO-d6 at two magnetic field strengths, with standard deviations ≤1%. The combination of MD simulation and a stochastic description based on the diffusive chain model resulted in excellent agreement between calculated and experimentally observed (13)C relaxation parameters, with an average error of <2%. The coupling between the global reorientation of the molecule and the local motion of the spin probe is deemed essential if reproduction of NMR relaxation parameters should succeed, since decoupling of the two modes of motion results in significantly worse agreement. Calculation of (13)C relaxation parameters based on the correlation functions obtained directly from the MD simulation of the solute molecule in DMSO as solvent showed satisfactory agreement with errors on the order of 10% or less. PMID:26741055

  19. Crystal structure of catena-poly[[(dimethyl sulfoxide-κO)(pyridine-2,6-di-carboxyl-ato-κ(3) O,N,O')nickel(II)]-μ-pyrazine-κ(2) N:N'].

    PubMed

    Liu, Chen; Thuijs, Annaliese E; Felts, Ashley C; Ballouk, Hamza F; Abboud, Khalil A

    2016-05-01

    The title coordination polymer, [Ni(C7H3NO4)(C4H4N2)(C2H6OS)] n , consists of [010] chains composed of Ni(II) ions linked by bis-monodentate-bridging pyrazine mol-ecules. Each of the two crystallographically distinct Ni(II) ions is located on a mirror plane and is additionally coordinated by a dimethyl sulfoxide (DMSO) ligand through the oxygen atom and by a tridentate 2,6-pyridine-di-carb-oxy-lic acid dianion through one of each of the carboxyl-ate oxygen atoms and the pyridine nitro-gen atom, leading to a distorted octa-hedral coordination environment. The title structure exhibits an inter-esting complementarity between coordinative bonding and π-π stacking where the Ni-Ni distance of 7.0296 (4) Å across bridging pyrazine ligands allows the pyridine moieties on two adjacent chains to inter-digitate at halfway of the Ni-Ni distance, resulting in π-π stacking between pyridine moieties with a centroid-to-plane distance of 3.5148 (2) Å. The double-chain thus formed also exhibits C-H⋯π inter-actions between pyridine C-H groups on one chain and pyrazine mol-ecules on the other chain. As a result, the inter-ior of the double-chain structure is dominated by π-π stacking and C-H⋯ π inter-actions, while the space between the double-chains is occupied by a C-H⋯O hydrogen-bonding network involving DMSO ligands and carboxyl-ate groups located on the exterior of the double-chains. This separation of dissimilar inter-actions in the inter-ior and exterior of the double-chains further stabilizes the crystal structure. PMID:27308038

  20. 5,8-Bis[bis-(pyridin-2-yl)amino]-1,3,4,6,7,9,9b-hepta-aza-phenalen-2(1H)-one dimethyl sulfoxide monosolvate dihydrate.

    PubMed

    Schwarzer, Anke; Kroke, Edwin

    2014-04-01

    In the asymmetric unit of the title compound, C26H17N13O·C2H6OS·2H2O, there is one independent hepta-zine-based main mol-ecule, one dimethyl sulfoxide mol-ecule and two water mol-ecules as solvents. The tri-s-triazine unit is substituted with two dipyridyl amine moieties and a carbonylic O atom. As indicated by the bond lengths in this acid unit of the hepta-zine derivative [C=O = 1.213 (2) Å, while the adjacent C-N(H) bond = 1.405 (2) Å] it is best described by the keto form. The cyameluric nucleus is close to planar (r.m.s. deviation = 0.061 Å) and the pyridine rings are inclined to its mean plane by dihedral angles varying from 47.47 (5) to 70.22 (5)°. The host and guest mol-ecules are connected via N-H⋯O, O-H⋯O and O-H⋯N hydrogen bonds, forming a four-membered inversion dimer-like arrangement enclosing an R 4 (4)(24) ring motif. These arrangements stack along [1-10] with a weak π-π inter-action [inter-centroid distance = 3.8721 (12) Å] involving adjacent pyridine rings. There are also C-H⋯N and C-H⋯O hydrogen bonds and C-H⋯π inter-actions present within the host mol-ecule and linking inversion-related mol-ecules, forming a three-dimensional structure. PMID:24826156

  1. Crystal structure of catena-poly[[(dimethyl sulfoxide-κO)(pyridine-2,6-di­carboxyl­ato-κ3 O,N,O′)nickel(II)]-μ-pyrazine-κ2 N:N′

    PubMed Central

    Liu, Chen; Thuijs, Annaliese E.; Felts, Ashley C.; Ballouk, Hamza F.; Abboud, Khalil A.

    2016-01-01

    The title coordination polymer, [Ni(C7H3NO4)(C4H4N2)(C2H6OS)]n, consists of [010] chains composed of NiII ions linked by bis-monodentate-bridging pyrazine mol­ecules. Each of the two crystallographically distinct NiII ions is located on a mirror plane and is additionally coordinated by a dimethyl sulfoxide (DMSO) ligand through the oxygen atom and by a tridentate 2,6-pyridine-di­carb­oxy­lic acid dianion through one of each of the carboxyl­ate oxygen atoms and the pyridine nitro­gen atom, leading to a distorted octa­hedral coordination environment. The title structure exhibits an inter­esting complementarity between coordinative bonding and π–π stacking where the Ni—Ni distance of 7.0296 (4) Å across bridging pyrazine ligands allows the pyridine moieties on two adjacent chains to inter­digitate at halfway of the Ni—Ni distance, resulting in π–π stacking between pyridine moieties with a centroid-to-plane distance of 3.5148 (2) Å. The double-chain thus formed also exhibits C—H⋯π inter­actions between pyridine C—H groups on one chain and pyrazine mol­ecules on the other chain. As a result, the inter­ior of the double-chain structure is dominated by π–π stacking and C—H⋯ π inter­actions, while the space between the double-chains is occupied by a C—H⋯O hydrogen-bonding network involving DMSO ligands and carboxyl­ate groups located on the exterior of the double-chains. This separation of dissimilar inter­actions in the inter­ior and exterior of the double-chains further stabilizes the crystal structure. PMID:27308038

  2. [Treatment of amyloidosis with dimethyl sulfoxide (DMSO)].

    PubMed

    Morassi, P; Massa, F; Mesesnel, E; Magris, D; D'Agnolo, B

    1989-01-01

    In this study we have investigated the role of oral dimethylsulfoxide (DMSO) therapy in 2 patients with primary amyloidosis (AL) and in 2 patients with secondary amyloidosis (AA) to long-standing rheumatoid arthritis. DMSO treatment produced no beneficial effects in the patients with idiopathic amyloidosis. Instead the patients with secondary amyloidosis experienced a subjective improvement, a decrease of inflammatory activity of the rheumatoid arthritis and an unequivocal improvement of renal function following 3-6 months of DMSO therapy. No serious side effects of DMSO were observed except for unpleasant breath odour. We conclude that a treatment with oral DMSO may prolong life of patients with secondary amyloidosis. PMID:2915815

  3. Crystal structure of 6-amino-4-(3-bromo-4-meth­oxy­phen­yl)-3-methyl-2,4-di­hydro­pyrano[2,3-c]pyrazole-5-carbo­nitrile dimethyl sulfoxide monosolvate

    PubMed Central

    Yousuf, Sammer; Bano, Huma; Muhammad, Munira Taj; Khan, Khalid Mohammed

    2015-01-01

    In the pyrazole mol­ecule of the title solvate, C15H13BrN4O2·C2H6OS, the dihedral angle between the benzene ring and the mean plane of the di­hydro­pyrano[2,3-c]pyrazole ring system [r.m.s deviation = 0.031 (2) Å] is 86.71 (14)°. In the crystal, the pyrazole mol­ecules are linked by N—H⋯N hydrogen bonds, forming a layer parallel to (10-1). The pyrazole and dimethyl sulfoxide mol­ecules are connected by an N—H⋯O hydrogen bond. PMID:26279904

  4. (S)-N-[(4-{(S)-1-[2-(4-Meth-oxy-benz-amido)-2-methyl-propano-yl]pyrrolidine-2-carboxamido}-3,4,5,6-tetra-hydro-2H-pyran-4-yl)carbon-yl]proline dimethyl sulfoxide monosolvate (4-MeBz-Aib-Pro-Thp-Pro-OH).

    PubMed

    Stoykova, Svetlana A; Linden, Anthony; Heimgartner, Heinz

    2013-03-01

    The asymmetric unit of the title compound, C28H38N4O8·C2H6OS, contains one tetra-peptide and one disordered dimethyl sulfoxide (DMSO) mol-ecule. The central five-membered ring (Pro(2)) of the peptide mol-ecule has a disordered envelope conformation [occupancy ratio 0.879 (2):0.121 (2)] with the envelope flap atom, the central C atom of the three ring methylene groups, lying on alternate sides of the mean ring plane. The terminal five-membered ring (Pro(4)) also adopts an envelope conformation with the C atom of the methylene group closest to the carboxylic acid function as the envelope flap, and the six-membered tetra-hydro-pyrane ring shows a chair conformation. The tetra-peptide exists in a helical conformation, stabilized by an intra-molecular hydrogen bond between the amide N-H group of the heterocyclic α-amino acid Thp and the amide O atom of the 4-meth-oxy-benzoyl group. This inter-action has a graph set motif of S(10) and serves to maintain a fairly rigid β-turn structure. In the crystal, the terminal hy-droxy group forms a hydrogen bond with the amide O atom of Thp of a neighbouring mol-ecule, and the amide N-H group at the opposite end of the mol-ecule forms a hydrogen bond with the amide O atom of Thp of another neighbouring mol-ecule. The combination of both inter-molecular inter-actions links the mol-ecules into an extended three-dimensional framework. PMID:23476594

  5. Foreign compounds and intermediary metabolism: sulfoxidation bridges the divide.

    PubMed

    Mitchell, S C; Steventon, G B

    2009-03-01

    It is widely appreciated that as a xenobiotic travels through an organism and interacts with the biochemical machinery of a living system, it most probably will undergo a number of metabolic alterations usually leading to a cluster of differing chemical species. Indeed, the modern 'metabonomic' approach, where earlier studied drug metabolism profiles have been reassessed, has indicated that there are normally many more previously unrecognised minor metabolites, and when all such biotransformation products are considered, then their total number is legion. It is now being recognised also that the same metabolic alteration of a substrate, especially a xenobiotic substrate, may be catalysed by more than one enzyme and that the previously sacrosanct notion of an enzyme's 'substrate specificity' may well be inverted to read a substrate's 'enzyme preference'. The following brief article attempts to highlight another aspect where our general acceptance of the 'status quo' needs to be reconsidered. The conventionally acknowledged division between the collection of enzymes that undertake intermediary metabolism and the group of enzymes responsible for xenobiotic metabolism may be becoming blurred. It may well be a prudent time to reassess the current dichotomous view. Overcoming inertia, with a realignment of ideas or alteration of perception, may permit new concepts to emerge leading to a more profound understanding and hopefully eventual benefits for mankind. PMID:19442084

  6. Enantioselective Sulfoxidation Catalyzed by a Bisguanidinium Diphosphatobisperoxotungstate Ion Pair.

    PubMed

    Ye, Xinyi; Moeljadi, Adhitya Mangala Putra; Chin, Kek Foo; Hirao, Hajime; Zong, Lili; Tan, Choon-Hong

    2016-06-13

    The first enantioselective tungstate-catalyzed oxidation reaction is presented. High enantioselectivities were achieved for a variety of drug-like phenyl and heterocyclic sulfides under mild conditions with H2 O2 , a cheap and environmentally friendly oxidant. Synthetic utility was demonstrated through the preparation of (S)-Lansoprazole, a commercial proton-pump inhibitor. The active ion-pair catalyst was identified to be bisguanidinium diphosphatobisperoxotungstate using Raman spectroscopy and computational studies. PMID:27150978

  7. [Effect of sulfur nutrition for sulfoxide accumulation in garlic bulbs].

    PubMed

    Kosian, A M

    1998-01-01

    The influence of the sulphur nutrition conduction upon sulphoxides accumulation in the garlic bulbs was studied. It was found that application of sulphur as ammonium sulphate in quantity up to 75-100 kg S/ha induced proportional increase of sulphoxides in bulbs from 3.03 up to 4.57 mg/g. Subsequent increasing of the sulphur doses applied did not induce any trustworthy changes. When potassium sulphate was used for feeding similar results were obtained. The potassium and nitrogen increase equivalent to the amounts of them applied together with sulphur did not induce any trustworthy changes too. Also it was registered the garlic variety sulphur nutrition specificity, that was closely connected with degree of the floral spear development. So, in the bulbs of non-spear-forming variety (Ukrainian white) the maximal increasing of the sulphoxide content was 78.6% against control whereas for Boguslavsky 10, the variety with most advanced floral spear (with height up to 125 cm), the increasing of sulphoxides was only 43.6%. PMID:9848149

  8. EFFECT OF DIETARY LIPID AND DIMETHYL SULFOXIDE ON LINDANE METABOLISM

    EPA Science Inventory

    Previous investigations have suggested that there is a requirement of dietary polyunsaturated fatty acids for full expression of microsomal enzyme induction. The conclusions in these studies were primarily based on in vitro enzyme activity, sleeping time recovery, or hepatic cyto...

  9. 21 CFR 524.660b - Dimethyl sulfoxide gel.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... swelling due to trauma. (2) Amount—(i) Horses. Administer 2 or 3 times daily in an amount not to exceed 100 grams per day. Total duration of therapy should not exceed 30 days. (ii) Dogs. Administer 3 or 4 times daily in an amount not to exceed 20 grams per day. Total duration of therapy should not exceed 14...

  10. Transformation of Schizosaccharomyces pombe: Lithium Acetate/ Dimethyl Sulfoxide Procedure.

    PubMed

    Murray, Johanne M; Watson, Adam T; Carr, Antony M

    2016-04-01

    Transformation ofSchizosaccharomyces pombewith DNA requires the conditioning of cells to promote DNA uptake followed by cell growth under conditions that select and maintain the plasmid or integration event. The three main methodologies are electroporation, treatment with lithium cations, and transformation of protoplasts. The lithium acetate method described here is widely used because it is simple and reliable. PMID:27037075

  11. Obesity reduces methionine sulfoxide reductase activity in visceral adipose tissue

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Visceral obesity is linked to the development of comorbidities including insulin resistance and cardiovascular disease. Elevated levels of oxidative stress are observed in obese individuals and in animal models of obesity, pointing to a mechanistic role of oxidative stress. A recent genetic study in...

  12. Cyclodextrin inclusion compounds of vanadium complexes: structural characterization and catalytic sulfoxidation.

    PubMed

    Lippold, Ines; Vlay, Kristin; Görls, Helmar; Plass, Winfried

    2009-04-01

    Reaction of potassium vanadate with the hydrazone ligand derived from Schiff-base condensation of salicylaldehyde and biphenyl-4-carboxylic acid hydrazide (H(2)salhybiph) in the presence of two equivalents alpha-cyclodextrin (alpha-CD) in water yields the 1:2 inclusion compound K[VO(2)(salhybiph)@(alpha-CD)(2)]. Characterization in solution confirmed the integrity of the inclusion compound in the polar solvent water. The inclusion compound crystallizes together with additional water molecules as K[VO(2)(salhybiph)@(alpha-CD)(2)].18H(2)O in the monoclinic space group P2(1). Two alpha-CD rings forming a hydrogen bonded head to head dimer are hosting the hydrophobic biphenyl side chain of the complex K[VO(2)(salhybiph)]. The supramolecular aggregation of the inclusion compound in the solid state is established through hydrogen bonding interactions among adjacent alpha-CD hosts and with vanadate moieties of the guest complexes as well as ionic interactions with the potassium counterions. In contrast the supramolecular structure of the guest complex K[VO(2)(salhybiph)] without the presence of CD host molecules is governed by pi-pi-stacking interactions and additional CH/pi interactions. The new inclusion complex K[VO(2)(salhybiph)@(alpha-CD)(2)] and the analogous 1:1 inclusion compound with beta-CD were tested as catalyst in the oxidation of methyl phenyl sulfide (thioanisol) using hydrogen peroxide as oxidant in a water/ethanol mixture, under neutral as well as acidic conditions. PMID:19201031

  13. Facile synthesis of enantioenriched phenol-sulfoxides and their aluminum complexes.

    PubMed

    Tang, Yani; Sun, Yuji; Liu, Jiyong; Duttwyler, Simon

    2016-06-15

    Chiral phenolic p-tolylsulfoxides and t-butylsulfoxides were prepared by several short synthetic routes starting from readily available starting materials. The key synthetic step was the reaction of lithiated arenes with menthyl sulfinates or enantioselective oxidation of a t-butyl sulfide. Well-defined neutral ligand-AlMe2 complexes were obtained by stoichiometric treatment with AlMe3. PMID:26996318

  14. Alteration of the electrophoretic mobility of human peripheral blood mononuclear cells following treatment with dimethyl sulfoxide

    SciTech Connect

    Skrabut, E.M.; Catsimpoolas, N.; Kurtz, S.R.; Griffith, A.L.; Valeri, C.R.

    1983-12-01

    Studies have been conducted to determine the effects of DMSO and freezing on the electrophoretic distribution of peripheral blood mononuclear cells. Sodium (/sup 51/Cr)chromate was used to label the cells, and the distributions of cell number and cell-associated radioactivity were determined. Cells treated with DMSO had a narrower distribution of electrophoretic mobilities when compared with those not treated. DMSO-treated cells also demonstrated a more homogeneous distribution of radioactivity relative to the cell distribution than did the nontreated cells. The freezing of DMSO-treated cells did not result in any additional alteration of electrophoretic pattern compared to DMSO treatment alone. Analysis by linear categorization techniques indicated that the DMSO-treated and nontreated cells were completely distinguished by their electrophoretic behavior.

  15. Efficient uptake of dimethyl sulfoxide by the desoxomolybdenum(IV) dithiolate complex containing bulky hydrophobic groups.

    PubMed

    Hasenaka, Yuki; Okamura, Taka-aki; Onitsuka, Kiyotaka

    2015-04-01

    A desoxomolybdenum(IV) complex containing bulky hydrophobic groups and NH···S hydrogen bonds, (Et4N)[Mo(IV)(OSi(t)BuPh2)(1,2-S2-3,6-{(4-(t)BuC6H4)3CCONH}2C6H2)2], was synthesized. This complex promotes the oxygen-atom-transfer (OAT) reaction of DMSO by efficient uptake of the substrate into the active center. The clean OAT reaction of Me3NO is also achieved. PMID:25739371

  16. Hexa­kis­(dimethyl sulfoxide-κO)zinc(II) poly­iodide

    PubMed Central

    Garzón-Tovar, Luis; Duarte-Ruiz, Álvaro; Fanwick, Phillip E.

    2013-01-01

    The title compound, [Zn{(CH3)2SO}6]I4, is a one-dimensional supra­molecular polymer along a threefold rotation axis of the space group. It is built up from discrete [Zn{(CH3)2SO}6]2+ units connected through non-classical hydrogen bonds to linear I4 2− polyiodide anions (C—H⋯I = 3.168 Å). The ZnII ion in the cation has an octa­hedral coordination geometry, with all six Zn—O bond lengths being equivalent, at 2.111 (4) Å. The linear polyiodide anion contains a neutral I2 mol­ecule weakly coordinated to two iodide ions. PMID:24454044

  17. Transcriptional regulation of dimethyl sulfoxide respiration in a haloarchaeon, Haloferax volcanii.

    PubMed

    Qi, Qiuzi; Ito, Yoshiyasu; Yoshimatsu, Katsuhiko; Fujiwara, Taketomo

    2016-01-01

    The halophilic euryarchaeon Haloferax volcanii can grow anaerobically by DMSO respiration. DMSO reductase was induced by DMSO respiration not only under anaerobic growth conditions but also in denitrifying cells of H. volcanii. Deletion of the dmsR gene, encoding a putative regulator for the DMSO reductase, resulted in the loss of anaerobic growth by DMSO respiration. Reporter experiments revealed that only the anaerobic condition was essential for transcription of the dmsEABCD genes encoding DMSO reductase and that transcription was enhanced threefold by supplementation of DMSO. In the ∆dmsR mutant, transcription of the dmsEABCD genes induced by the anaerobic condition was not enhanced by DMSO, suggesting that DmsR is a DMSO-responsive regulator. Transcriptions of the dmsR and mgd genes for Mo-bisMGD biosynthesis were regulated in the same manner as the dmsEABCD genes. These results suggest that the genetic regulation of DMSO respiration in H. volcanii is controlled by at least two systems: one is the DMSO-responsive DmsR, and the other is an unknown anaerobic regulator. PMID:26507955

  18. 21 CFR 524.981d - Fluocinolone acetonide, dimethyl sulfoxide solution.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... apparently normal anal sacs, for the reversal of inflammatory changes associated with abnormal anal sacs, and to counteract the offensive odor of anal sac secretions. (2) It is administered by instillation of 1 to 2 milliliters into each anal sac following expression of anal sac contents. It may be necessary...

  19. 21 CFR 524.981d - Fluocinolone acetonide, dimethyl sulfoxide solution.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... apparently normal anal sacs, for the reversal of inflammatory changes associated with abnormal anal sacs, and to counteract the offensive odor of anal sac secretions. (2) It is administered by instillation of 1 to 2 milliliters into each anal sac following expression of anal sac contents. It may be necessary...

  20. 21 CFR 524.981d - Fluocinolone acetonide, dimethyl sulfoxide solution.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... apparently normal anal sacs, for the reversal of inflammatory changes associated with abnormal anal sacs, and to counteract the offensive odor of anal sac secretions. (2) It is administered by instillation of 1 to 2 milliliters into each anal sac following expression of anal sac contents. It may be necessary...

  1. 21 CFR 524.981d - Fluocinolone and dimethyl sulfoxide solution.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 1 to 2 milliliters into each anal sac following expression of anal sac contents. (2) Indications for use. For the relief of impaction commonly present in apparently normal anal sacs, for the reversal of inflammatory changes associated with abnormal anal sacs, and to counteract the offensive odor of anal...

  2. 21 CFR 524.981d - Fluocinolone acetonide, dimethyl sulfoxide solution.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... apparently normal anal sacs, for the reversal of inflammatory changes associated with abnormal anal sacs, and to counteract the offensive odor of anal sac secretions. (2) It is administered by instillation of 1 to 2 milliliters into each anal sac following expression of anal sac contents. It may be necessary...

  3. Interaction of Product Analogues With the Active Site of Rhodobacter Sphaeroides Dimethyl Sulfoxide Reductase

    SciTech Connect

    George, G.N.; Nelson, K.J.; Harris, H.H.; Doonan, C.J.; Rajagopalan, K.V.; /Saskatchewan U. /Duke U. /Sydney U.

    2007-07-09

    We report a structural characterization using X-ray absorption spectroscopy of Rhodobacter sphaeroides dimethylsulfoxide (DMSO) reductase reduced with trimethylarsine, and show that this is structurally analogous to the physiologically relevant dimethylsulfide-reduced DMSO reductase. Our data unambiguously indicate that these species should be regarded as formal MoIV species, and indicate a classical coordination complex of trimethylarsine oxide, with no special structural distortions. The similarity of the trimethylarsine and dimethylsulfide complexes suggests in turn that the dimethylsulfide reduced enzyme possesses a classical coordination of DMSO with no special elongation of the S-O bond, as previously suggested.

  4. Association in ethylammonium nitrate-dimethyl sulfoxide mixtures: First structural and dynamical evidences

    SciTech Connect

    Russina, Olga; Macchiagodena, Marina; Kirchner, Barbara; Mariani, Alessandro; Aoun, Bachir; Russina, Margarita; Caminiti, Ruggero; Triolo, Alessandro

    2015-01-01

    Here we report the first structural and dynamic investigation on ethylammonium nitrate, a representative protic Ionic liquid, and dimethylsulfoxide. By using joined x/ray and neutron diffraction, we exploit the EPSR approach to extract structural information at atomistic level. EAN/DMSO turns out to be homogeneous at microscopic scales and indications for the existence of a structural leit motiv with stoichiometric composition 2DMSO:1EAN are found. Dielectric spectroscopy is used to access the relaxation map of the DMSO:EAN = 60:40 mixture. No crystallisation is detected and three relaxation processes could be characterised. Overall this study provides new indications of strict analogies between water and ethylammonium nitrate. (c) 2014 Elsevier B.V. All rights reserved.

  5. Extraction of /sup 14/C-labeled photosynthate from aquatic plants with dimethyl sulfoxide (DMSO)

    SciTech Connect

    Filbin, G.J.; Hough, R.A.

    1984-03-01

    DMSO was tested as a solvent to extract /sup 14/C-labeled photosynthate from three species of aquatic plants in photosynthesis measurements and compared with the dry oxidation method for plant radioassay. Extraction of ca. 300 mg of fresh or rehydrated dry plant tissue samples in 10 ml of reagent-grade DMSO for 8h at 65/sup 0/C resulted in a stable, nonviscous solution with excellent liquid scintillation counting characteristics. Extraction efficiency was in the range of 96-99% of fixed /sup 14/C, and precision was comparable to, or better than, that obtained with dry oxidation. The method is simple and inexpensive, and for fresh tissue the same sample extracts can be used for chlorophyll analyses.

  6. Extraction of /sup 14/C-labeled photosynthate from aquatic plants with dimethyl sulfoxide (DMSO)

    SciTech Connect

    Filbin, G.J.; Hough, R.A.

    1984-03-01

    DMSO was tested as a solvent to extract /sup 14/C-labeled photosynthate from three species of aquatic plants in photosynthesis measurements and compared with the dry oxidation method for plant radioassay. Extraction efficiency was in the range of 96-99% of fixed /sup 14/C, and precision was comparable to, or better than, that obtained with dry oxidation. The method is simple and inexpensive, and for fresh tissue the same sample extracts can be used for chlorophyll analyses.

  7. Probe Dependent Solvation Dynamics Study in a Microscopically Immiscible Dimethyl Sulfoxide-Glycerol Binary Solvent.

    PubMed

    Kaur, Harveen; Koley, Somnath; Ghosh, Subhadip

    2014-06-26

    Excited state dipole solvation of three coumarin dyes with different hydrophobicities was studied in DMSO-glycerol binary solvent. The solvation times obtained from the three dyes are remarkably different. The highly hydrophilic dye coumarin 343 (C343) exhibits the slowest solvation time (>12 ns) among all the dyes we used. This is in contrast to the most hydrophobic dye coumarin 153 (C153), where the solvated state is reached just within ∼104 ps. However, the moderately hydrophobic dye coumarin 480 (C480) demonstrates an intermediate (∼396 ps) solvation time. Unprecedented slowdown of solvation time of C343 is probably due to the slow diffusion of solvent molecules in the glycerol-rich first solvation shell followed by hydrogen bond rearrangements around the solute dipole. On the other hand, fast solvation of hydrophobic dye C153 is most likely caused by the fast reorganization dynamics of hydrophobic -CH3 groups of DMSO or the carbon backbone of the glycerol molecule around the solute dipole. Interestingly, a remarkable probe dependency in solvation dynamics was not observed in the case of DMSO-water binary solvent or in a neat solvent isopropanol. Probe dependent solvation in a DMSO-glycerol mixture is attributed to the microscopic phase segregation and different locations of coumarin dyes within this binary solvent. PMID:24942350

  8. Effects of intratesticular administration of zinc gluconate and dimethyl sulfoxide on clinical, endocrinological, and reproductive parameters in dogs.

    PubMed

    Vannucchi, C I; Angrimani, D S R; Eyherabide, A R; Mazzei, C P; Lucio, C F; Maiorka, P C; Silva, L C G; Nichi, M

    2015-10-15

    Nonsurgical sterilization methods are considered alternative tools for the worldwide challenge represented by canine overpopulation control. Intratesticular injection of zinc gluconate associated with DMSO arises as an option because of the effortless diffusion throughout the testicular parenchyma. This study aimed to verify the effectiveness of a double testicular injection of zinc gluconate associated with DMSO as a chemical contraceptive for male dogs. The study was conducted with 22 dogs treated with two intratesticular injections of the chemical solution (treated group; n = 15) or 0.9% NaCl solution (control group; n = 7) on a monthly interval. All animals were submitted to clinical examination, breeding soundness evaluation including morphologic and sonographic examination of the testes, assessment of libido, volume of the sperm-rich fraction, sperm motility, total sperm count, plasma membrane integrity, sperm morphologic abnormalities, and the total number of morphologically normal and motile sperm in the ejaculate. Blood samples were collected for serum testosterone analysis, and testicular tissue was morphologically and histologically evaluated. No clinical alterations and signs of pain or local sensitivity along the experimental period were noticed. However, the injection of zinc gluconate and DMSO significantly reduced libido and testosterone concentrations (even beyond the reference range for intact male dogs). Impairment of sperm quality-related variables was observed 15 days after the first intratesticular administration of zinc gluconate and DMSO (i.e., decrease in sperm count and sperm motility and an increase in major sperm defects and by this a decrease in the total number of morphologically normal and motile sperm). Testicular ultrasonographic analysis revealed reduction of testicular volume and changes of testicular echotexture in treated animals, compatible with tissue degeneration, fibrosis, and calcification of testicular parenchyma on histologic examination. In conclusion, intratesticular administration of zinc gluconate associated with DMSO reduces reproductive potential which may lead to subfertility or infertility in dogs. PMID:26174036

  9. Meta-analysis of the related nutritional supplements dimethyl sulfoxide and methylsulfonylmethane in the treatment of osteoarthritis of the knee.

    PubMed

    Brien, Sarah; Prescott, Phil; Lewith, George

    2011-01-01

    Dimethyl sulphoxide and methylsulfonylmethane are two related nutritional supplements used for symptomatic relief of osteoarthritis (OA). We conducted a meta-analysis to evaluate their efficacy in reducing pain associated with OA. Randomized or quasi-randomized controlled trials (RCTs), identified by systematic electronic searches, citation tracking and searches of clinical trial registries, assessing these supplements in osteoarthritis of any joint were considered for inclusion. Meta-analysis, based on difference in mean pain related outcomes between treatment and comparator groups, was carried out based on a random effect model. Seven potential trials were identified of which three RCTs, two DMSO and one MSM (total N = 326 patients) were eligible for inclusion. All three trials were considered high methodological quality. A significant degree of heterogeneity (χ(2) = 6.28, P = .043) was revealed. Two studies demonstrated statistically significant (but not clinically relevant) reduction in pain compared with controls; with one showing no group difference. The meta-analysis confirmed a non significant reduction of pain on visual analogue scale of 6.34 mm (SE = 3.49, 95% CI, -0.49, 13.17). The overall effect size of 1.82 was neither statistically nor clinically significant. Current evidence suggests DMSO and MSM are not clinically effective in the reduction of pain in the treatment of OA. No definitive conclusions can currently be drawn from the data due to the mixed findings and the use of inadequate dosing periods. PMID:19474240

  10. Stereoselective 6-exo radical cyclization using cis-vinyl sulfoxide: practical total synthesis of CTX3C.

    PubMed

    Yamashita, Shuji; Ishihara, Yuuki; Morita, Hiroyuki; Uchiyama, Junichi; Takeuchi, Katsutoshi; Inoue, Masayuki; Hirama, Masahiro

    2011-03-25

    Ciguatoxins, the principal causative toxins of ciguatera seafood poisoning, are large ladder-like polycyclic ethers. We report a highly stereoselective 6-exo radical cyclization/ring-closing olefin metathesis sequence to construct the syn/trans-fused polyether system. The new method was applied to the practical synthesis of ciguatoxin CTX3C. PMID:21250701

  11. Altered Hepa1-6 cells by dimethyl sulfoxide (DMSO)-treatment induce anti-tumor immunity in vivo

    PubMed Central

    Jiang, Zhengyu; Zhang, Hongxia; Wang, Ye; Yu, Bin; Wang, Chen; Liu, Changcheng; Lu, Juan; Chen, Fei; Wang, Minjun; Yu, Xinlu; Lin, Jiahao; Pan, Xinghua; Wang, Pin; Zhu, Haiying

    2016-01-01

    Cancer immunotherapy is the use of the immune system to treat cancer. Our current research proposed an optional strategy of activating immune system involving in cancer immunotherapy. When being treated with 2% DMSO in culture medium, Hepa1-6 cells showed depressed proliferation with no significant apoptosis or decreased viability. D-hep cells, Hepa1-6 cells treated with DMSO for 7 days, could restore to the higher proliferation rate in DMSO-free medium, but alteration of gene expression profile was irreversible. Interestingly, tumors from D-hep cells, not Hepa1-6 cells, regressed in wild-type C57BL/6 mice whereas D-hep cells exhibited similar tumorigenesis as Hep1–6 cells in immunodeficient mice. As expected, additional Hepa1-6 cells failed to form tumors in the D-hep-C57 mice in which D-hep cells were eliminated. Further research confirmed that D-hep-C57 mice established anti-tumor immunity against Hepa1-6 cells. Our research proposed viable tumor cells with altered biological features by DMSO-treatment could induce anti-tumor immunity in vivo. PMID:26824185

  12. Molecular biological enhancement of coal desulfurization: Cloning and expression of the sulfoxide/sulfone/sulfonate/sulfate genes in Pseudomonads and Thiobacillae

    SciTech Connect

    Krawiec, S.

    1991-08-30

    The DbtS{sup +} phenotype is defined as the selective ability to oxidize the sulfur in dibenzothiophene (DBT) successively to dibenzothiophene-5-oxide, dibenzosulfone, and, finally, either o, o'-biphenol or monohydroxybiphenyl. By using a fluorescent assay, many Pseudomonas putida isolates having a DbtS{sup +} phenotype have been obtained. The ability of the isolates to generate o, o'-biphenol was confirmed with HPLC shortly after the time of isolation. The broad-host-range plasmid, R68.45, was introduced from P. putida PRS 2003 into many soil isolates. The plasmid was able to mobilize the determinants for the DbtS{sup +} phenotype. Accordingly, R68.45 and the determinants of the phenotype could be transferred simultaneously form soil isolates to P. aeruginosa 27853. The DbtS{sup +} phenotype in the isolates and in P. aeruginosa 27853 has proven to be unstable. Whether the instability is genetic, physiological, some combination of these two, or is founded on some other phenomenon is not known. Fresh Gram-positive isolates with the DbtS{sup +} phenotype have been isolated using the sulfur bioavailability assay. The DbtS{sup +} phenotype in these isolates appears to be stable. The product of desulfurization of DBT of dibenzosulfone is monohydroxybiphenyl. The nature of the endproduct has been confirmed by HPLC, colorimetry, GC/mass spectroscopy, and UV absorption. The kinetics of monohydroxybiphenyl production are being studied in batch and continuous culture. Study of the basis of cloning with R68.45 has continued. Data regarding in vivo cloning with R68.45 will be important when the genetic determinants for the DbtS{sup +} phenotype must be moved from one species to another by natural processes'' rather than through methods of genetic engineering. 8 refs., 3 figs.

  13. Molecular biological enhancement of coal desulfurization: Cloning and expression of the sulfoxide/sulfone/sulfonate/sulfate genes in Pseudomonads and Thiobacillae. [Rhodococcus erythropolis, Thiobacillus acidophilus, Thiobacillus novellus

    SciTech Connect

    Krawiec, S.

    1992-01-01

    Research continues on desulfurization of coal using microorganisms. Topics reported on this quarter include: desulfurization with N1-36 (presumptively identified as Rhodochrous erythropolis), pulsed-field gel electrophoresis of chromosomal DNA's of Thiobacillus spp., and fresh isolates with the presumptive capacity to desulfurize dibenzothiophenes.

  14. Molecular biological enhancement of coal desulfurization: Cloning and expression of the sulfoxide/sulfone/sulfonate/sulfate genes in Pseudomonads and Thiobacillae

    SciTech Connect

    Krawiec, S.

    1991-11-09

    This department of energy-sponsored mission-oriented research project currently has three emphases. They are: (1) determining the kinetics of monohydroxybiphenyl (OH-BP) production in batch culture by N1-36, an unidentified soil isolate, when the organism is presented with dibenzothiophene (DBT) or dibenzosulfone (DBTO{sub 2}); (2) establishing reliable methods for physically characterizing R68.45, a broad host range plasmid; and (3) attempting to elicit a physiologically consistent and genetically stable ability of some gram negative soil isolates to convert DBT to o,o{prime}-biphenol. Eachh of these goals has subsidiary components. For example, in addition to establishing kinetics of formation of OH-BP by N1-36, analyses have been or will be performed to determine whether the catalytic activity can be achieved with irradiated cells, spheroplasts, and cell extracts. This report presents information on progress towards fulfilling both the principal goals listed above and some relevant ancillary activities.

  15. Molecular biological enhancement of coal desulfurization: Cloning and expression of the sulfoxide/sulfone/sulfonate/sulfate genes in Pseudomonads and Thiobacillae. Ninth quarterly report, [July--October 1991

    SciTech Connect

    Krawiec, S.

    1991-11-09

    This department of energy-sponsored mission-oriented research project currently has three emphases. They are: (1) determining the kinetics of monohydroxybiphenyl (OH-BP) production in batch culture by N1-36, an unidentified soil isolate, when the organism is presented with dibenzothiophene (DBT) or dibenzosulfone (DBTO{sub 2}); (2) establishing reliable methods for physically characterizing R68.45, a broad host range plasmid; and (3) attempting to elicit a physiologically consistent and genetically stable ability of some gram negative soil isolates to convert DBT to o,o{prime}-biphenol. Eachh of these goals has subsidiary components. For example, in addition to establishing kinetics of formation of OH-BP by N1-36, analyses have been or will be performed to determine whether the catalytic activity can be achieved with irradiated cells, spheroplasts, and cell extracts. This report presents information on progress towards fulfilling both the principal goals listed above and some relevant ancillary activities.

  16. Molecular biological enhancement of coal desulfurization: Cloning and expression of the sulfoxide/sulfone/sulfonate/sulfate genes in Pseudomonads and Thiobacillae. Eleventh quarterly report

    SciTech Connect

    Krawiec, S.

    1992-08-01

    Research continues on desulfurization of coal using microorganisms. Topics reported on this quarter include: desulfurization with N1-36 (presumptively identified as Rhodochrous erythropolis), pulsed-field gel electrophoresis of chromosomal DNA`s of Thiobacillus spp., and fresh isolates with the presumptive capacity to desulfurize dibenzothiophenes.

  17. Molecular biological enhancement of coal desulfurization: Cloning and expression of the sulfoxide/sulfone/sulfonate/sulfate genes in Pseudomonads and Thiobacillae

    SciTech Connect

    Krawiec, S.

    1990-10-22

    Research continued on coal desulfurization and the study of biological enhancement of desulfurization. This quarters work included: crosses between soil isolates containing r68.45 and P. aeruginosa 27853-2a; extents of crosses and abundances of transconjugants; purpose of repeated crosses; noteworthy features of mating protocol; phenotypic peculiarities and phenotypic stabilities of transconjugants; characterization of antibiotic sensitivity; effect of receiving R68.45 from P. putida PRS 2003; transfer of R68.45 from C18 to auxotrophs derived from P. aeruginosa 27853; and differences in ability of various soil isolates to transfer Dbt{sup +} phenotype to recipient cells; incipient characterizations of Thiobacillae spp. growth and antibiotic sensitivity; plasmid isolation; and acquisition of new soil isolates.

  18. Molecular biological enhancement of coal desulfurization: Cloning and expression of the sulfoxide/sulfone/sulfonate/sulfate genes in pseudomonads and thiobacillae

    SciTech Connect

    Krawiec, S.

    1991-02-04

    A genetic character is a stable, heritable feature of an organism. Such genetic features are manifest in phenotypes. The preceding claims are fundamental tenets of genetic analysis. Observations which conform to these claims are reliable. But sometimes observations from carefully executed experiments do not correspond with expectation. Traits sometimes are not stable, or they are transmitted irregurlarly to subsequent generations, or the phenotype exhibits variation for reasons which are not readily identifiable. Such confounding circumstances have characterized the research efforts of the Lehigh group during the past quarter. A useful aspect of unanticipated laboratory observations is that they necessitate an examination of the hypotheses, protocols, procedures, materials et cetera used in experimentation. Much of the progress during the current quarter comes from such assessments. 17 refs.

  19. Effects of the bifunctional sulfoxide MMS350, a radiation mitigator, on hematopoiesis in long-term bone marrow cultures and on radioresistance of marrow stromal cell lines.

    PubMed

    Shinde, Ashwin; Epperly, Michael W; Cao, Shaonan; Franicola, Darcy; Shields, Donna; Wang, Hong; Wipf, Peter; Sprachman, Melissa M; Greenberger, Joel S

    2014-01-01

    The ionizing irradiation mitigator MMS350 prolongs survival of mice treated with total-body irradiation and prevents radiation-induced pulmonary fibrosis when added to drinking water at day 100 after thoracic irradiation. The effects of MMS350 on hematopoiesis in long-term bone marrow culture and on the radiobiology of derived bone marrow stromal cell lines were tested. Long-term bone marrow cultures were established from C57BL/6NTac mice and maintained in a high-humidity incubator, with 7% CO2 and the addition of 100 μM MMS350 at the weekly media change. Over 10 weeks in culture, MMS350 had no significant effect on maintenance of hematopoietic stem cell production, or on nonadherent cells or colony-forming units of hematopoietic progenitor cells. Stromal cell lines derived from non MMS350-treated long-term cultures or control stromal cells treated with MMS350 were radioresistant in the clonogenic survival curve assay. MMS350 is a non-toxic, highly water-soluble radiation mitigator that exhibits radioprotective effects on bone marrow stromal cells. PMID:24982210

  20. Free amino acid and cysteine sulfoxide composition of 11 garlic (Allium sativum L.) cultivars by gas chromatography with flame ionization and mass selective detection.

    PubMed

    Lee, Jungmin; Harnly, James M

    2005-11-16

    Two garlic subspecies (n = 11), Allium sativum L. var. opioscorodon (hardneck) and Allium sativum L. var. sativum (softneck), were evaluated for their free amino acid composition. The free amino acid content of garlic samples analyzed ranged from 1121.7 to 3106.1 mg/100 g of fresh weight (mean = 2130.7 +/- 681.5 mg/100 g). Hardneck garlic had greater methiin, alliin, and total free amino acids contents compared to softneck garlic. The major free amino acid present in all but one subspecies was glutamine (cv. Mother of Pearl had aspartic acid as the major free amino acid). Cv. Music Pink garlic (a rocambole hardneck variety) contained the most methiin, alliin, and total free amino acids. The solid-phase extraction, alkylchloroformate derivatization, GC-FID, and GC-MS methods used in this study were simple and rapid, allowing 18 free amino acids in garlic to be separated within 10 min. PMID:16277408

  1. Dietary Selenium (Se) and Copper (Cu) Affect the Activity and Expression of the Hepatic Selenoprotein Methionine Sulfoxide Reductase B (MrsB) in Rats

    Technology Transfer Automated Retrieval System (TEKTRAN)

    As reported by Jenkinson et al. (J Nutr 1982) and Prohaska et al. (J Nutr Biochem 1992) Cu deficiency (CuD) decreases the activity and mRNA expression of the selenoprotein GPx. Because both Se and Cu are important in oxidative defense, we wanted to determine the effect of a combined deficiency on th...

  2. Predicting the stability of aprotic solvents in Li-air batteries: pKa calculations of aliphatic C-H acids in dimethyl sulfoxide

    NASA Astrophysics Data System (ADS)

    Bryantsev, Vyacheslav S.

    2013-02-01

    Superoxide is a strong base that can induce base-catalyzed autoxidation of weakly acidic solvents. We report on the performance of several computational protocols for predicting pKa values for a wide range of aliphatic C-H acids in DMSO. Calculations at the MP2/CBS level with CCSD(T)/aug-cc-pVDZ corrections and solvent effects calculated using the SVPE model provide the best overall performance (rms deviation is 0.65 pKa). The B3LYP, M06, and M06-2X functionals can also achieve high accuracy (<1 pKa) by employing empirical corrections to fit the experimental data. Computational results provide a convenient means of screening for suitable solvents in Li-air batteries.

  3. A novel development of dithizone as a dual-analyte colorimetric chemosensor: detection and determination of cyanide and cobalt (II) ions in dimethyl sulfoxide/water media with biological applications.

    PubMed

    Tavallali, Hossein; Deilamy-Rad, Gohar; Parhami, Abolfath; Mousavi, Seyede Zahra

    2013-08-01

    The behavior of dithizone (DTZ), an easily available dye has been studied for the first time in chromogenic sensing of CN(-) as an anionic species and for Co(2+) as a cationic species in DMSO/H2O media. So employing DTZ an efficient colorimetric chemosensor was afforded with a chromogenic selectivity for Co(2+) over other cations with detection limit of 0.04 μmol L(-1). The complex of Co(2+) with DTZ also displayed ability to detect up to 0.43 μmol L(-1) CN(-) (K(+) salts) among other competing anions through a fast response time of less than 30s which is much lower than most recently reported chromogenic probes. The linear dynamic ranges for the determination of Co(2+) and CN(-) were 0.3-4.4 and 3.3-58.6 μmol L(-1) respectively. This method could have potential application in a variety of cases requiring rapid and accurate analysis of Co(2+) and CN(-) for human serum and water samples. PMID:23811160

  4. Synthesis, chemical reactivity, and antileukemic activity of 5-substituted 6,7-bis(hydroxymethyl)pyrrolo[1,2-c]thiazole biscarbamates and the corresponding sulfoxides and sulfones.

    PubMed

    Anderson, W K; Mach, R H

    1987-11-01

    A series of bis(N-methylcarbamate) and bis[N-(2-propyl)carbamate] derivatives of 5-substituted 6,7-bis(hydroxy-methyl)pyrrolo[1,2-c]thiazoles was prepared. The compounds were tested for activity in vivo against P388 lymphocytic leukemia, and the chemical reactivities of the compounds were compared by using the model nucleophile 4-(4-nitrobenzyl)pyridine (NBP). The 5-(3,4-dichlorophenyl)-substituted biscarbamates 6b, 8b, and 12b were inactive and unreactive toward NBP. The 5-methyl-substituted biscarbamates 6a, 7a, 8a, 9a, 12a, and 13a were all active against murine P388 lymphocytic leukemia. The chemical reactivities of the active compounds depended on the oxidation state of the sulfur. The reactivity toward NBP followed the order S greater than SO much greater than SO2. The sulfones 12a and 13a are the most active compounds in this series, and their lack of reactivity toward NBP led to the suggestion that 12a and 13a are activated in vivo. PMID:3669018

  5. rac-Dichlorido(1-{(diphenyl­phosphan­yl)[2-(diphenyl­phosphan­yl)phen­yl]meth­yl}ferrocene-κ2 P,P′)palladium(II) dimethyl sulfoxide disolvate

    PubMed Central

    Schuecker, Raffael; Weissensteiner, Walter; Mereiter, Kurt

    2011-01-01

    The racemic title compound, [FePdCl2(C5H5)(C36H29P2)]·2(CH3)2SO, features a Pd-chelating 1,3-diphosphine, which is substituted at a P-bearing asymmetric C atom by a ferrocenyl group. The PdII atom is in a distorted quadratic coordination by two P and two Cl atoms with bond lengths of 2.2414 (3) and 2.2438 (3) Å for Pd—P, and 2.3452 (3) and 2.3565 (3) Å for Pd—Cl. The conformation of the Pd complex is controlled by an intra­molecular slipped π–π stacking inter­action between a phenyl and a cyclo­penta­dienyl ring with corresponding C⋯C distances starting at 3.300 (2) Å and the distance between ring centroids being 3.674 (2) Å. The crystal structure is stabilized by C—H⋯Cl and C—H⋯O hydrogen bonds. The (CH3)2SO solvent mol­ecules are arranged in layers parallel to (101) and are linked in pairs by C—H⋯O inter­actions. One (CH3)2SO mol­ecule is orientationally disordered [occupancy ratio 0.8766 (17):0.1234 (17)] with sulfur in two positions at both sides of its C2O triangle. PMID:22064964

  6. Crystal structure of μ-oxalodi­hydroxamato-bis­[(2,2′-bipyrid­yl)(di­methyl sulfoxide-κO)copper(II)] bis­(perchlorate)

    PubMed Central

    Odarich, Irina A.; Pavlishchuk, Anna V.; Kalibabchuk, Valentina A.; Haukka, Matti

    2016-01-01

    The centrosymmetric binuclear complex, [Cu2(C2H2N2O4)(C10H8N2)2(C2H6OS)2](ClO4)2, contains two copper(II) ions, connected through an N-deprotonated oxalodi­hydroxamic acid dianion, two terminal 2,2′-bi­pyridine ligands, and two apically coordinating dimethylsulfoxide mol­ecules. Two non-coordinating perchlorate anions assure electrical neutrality. The copper(II) ions in the complex dication [Cu2(C10H8N2)2(μ-C2H2N2O4)(C2H6SO)2]2+ are in an O2N3 square-pyramidal donor environment, the Cu–Cu separation being 5.2949 (4) Å. Two hydroxamate groups in the deprotonated oxalodi­hydroxamic acid are located trans to one each other. In the crystal, O—H⋯O and C—H⋯O hydrogen bonds link the complex cations to the perchlorate anions. Further C—H⋯O hydrogen bonds combine with π–π contacts with a centroid-to-centroid separation of 3.6371 (12) Å to stack the mol­ecules along the a-axis direction. PMID:26958375

  7. Volume properties of reverse micellar systems AOT/ n-heptane/DMSO-water

    NASA Astrophysics Data System (ADS)

    Sargsyan, A. R.; Shahinyan, G. A.; Markarian, S. A.

    2014-05-01

    The volume properties of reverse micellar systems bis(2-ethylhexyl) sulfosuccinate sodium salt/ n-heptane/dimethyl sulfoxide-water are studied via densitometry. The presence of dimethyl sulfoxide and the increase in its amount in a dimethyl sulfoxide-water mixed solvent raise the apparent volume of the polar phase. This increase is also observed when the degree of hydration of the polar core and the temperature are raised.

  8. Gold Sulfinyl Mesoionic Carbenes: Synthesis, Structure, and Catalytic Activity.

    PubMed

    Frutos, María; Avello, Marta G; Viso, Alma; Fernández de la Pradilla, Roberto; de la Torre, María C; Sierra, Miguel A; Gornitzka, Heinz; Hemmert, Catherine

    2016-08-01

    Gold mesoionic carbenes having a chiral sulfoxide group attached to the C4 position of the five membered ring have been prepared and tested as catalysts in the cycloisomerization of enynes. These new catalysts are very efficient, with the sulfoxide moiety playing a key role in their activity and the N1-substituent in control of the regioselectivity of these processes. PMID:27403763

  9. Mechanisms of fenthion activation in rainbow trout (Oncorhynchus mykiss) acclimated to hypersaline environments

    PubMed Central

    Lavado, Ramon; Rimoldi, John M.; Schlenk, Daniel

    2010-01-01

    Previous studies in rainbow trout have shown that acclimation to hypersaline environments enhances the toxicity to thioether organophosphate and carbamate pesticides. In order to determine the role of biotransformation in this process, the metabolism of the thioether organophosphate biocide, fenthion was evaluated in microsomes from gills, liver and olfactory tissues in rainbow trout (Oncorhynchus mykiss) acclimated to freshwater and 17‰ salinity. Hypersalinity acclimation increased the formation of fenoxon and fenoxon sulfoxide from fenthion in liver microsomes from rainbow trout, but not in gills or in olfactory tissues. NADPH-dependent and independent hydrolysis was observed in all tissues, but only NADPH-dependent fenthion cleavage was differentially modulated by hypersalinity in liver (inhibited) and gills (induced). Enantiomers of fenthion sulfoxide (65% and 35% R- and S-fenthion sulfoxide, respectively) were formed in liver and gills. The predominant pathway of fenthion activation in freshwater appears to be initiated through initial formation of fenoxon which may be subsequently converted to the most toxic metabolite fenoxon R-sulfoxide. However, in hypersaline conditions both fenoxon and fenthion sulfoxide formation may precede fenoxon sulfoxide formation. Stereochemical evaluation of sulfoxide formation, cytochrome P450 inhibition studies with ketoconazole and immunoblots indicated that CYP3A27 was primarily involved in the enhancement of fenthion activation in hypersaline-acclimated fish with limited contribution of FMO to initial sulfoxidation. PMID:19111563

  10. NMR determination of isosorbide dinitrate and beta-adrenergic blocking agents in tablets.

    PubMed

    Chiarelli, S N; Rossi, M T; Pizzorno, M T; Albonico, S M

    1982-10-01

    An NMR spectroscopic method for the determination of isosorbide dinitrate, alone or together with alprenolol or propranolol, is described. Spectra are determined in dimethyl sulfoxide-d6 containing maleic acid or 1,4-dinitrobenzene as internal standards. Both synthetic mixtures and commercial formulations were assayed, and the results were compared using compendial procedures. PMID:6128401

  11. Mechanisms of fenthion activation in rainbow trout (Oncorhynchus mykiss) acclimated to hypersaline environments

    SciTech Connect

    Lavado, Ramon Rimoldi, John M.; Schlenk, Daniel

    2009-03-01

    Previous studies in rainbow trout have shown that acclimation to hypersaline environments enhances the toxicity to thioether organophosphate and carbamate pesticides. In order to determine the role of biotransformation in this process, the metabolism of the thioether organophosphate biocide, fenthion was evaluated in microsomes from gills, liver and olfactory tissues in rainbow trout (Oncorhynchus mykiss) acclimated to freshwater and 17 per mille salinity. Hypersalinity acclimation increased the formation of fenoxon and fenoxon sulfoxide from fenthion in liver microsomes from rainbow trout, but not in gills or in olfactory tissues. NADPH-dependent and independent hydrolysis was observed in all tissues, but only NADPH-dependent fenthion cleavage was differentially modulated by hypersalinity in liver (inhibited) and gills (induced). Enantiomers of fenthion sulfoxide (65% and 35% R- and S-fenthion sulfoxide, respectively) were formed in liver and gills. The predominant pathway of fenthion activation in freshwater appears to be initiated through initial formation of fenoxon which may be subsequently converted to the most toxic metabolite fenoxon R-sulfoxide. However, in hypersaline conditions both fenoxon and fenthion sulfoxide formation may precede fenoxon sulfoxide formation. Stereochemical evaluation of sulfoxide formation, cytochrome P450 inhibition studies with ketoconazole and immunoblots indicated that CYP3A27 was primarily involved in the enhancement of fenthion activation in hypersaline-acclimated fish with limited contribution of FMO to initial sulfoxidation.

  12. Biotransformation of chlorpromazine and methdilazine by Cunninghamella elegans.

    PubMed Central

    Zhang, D; Freeman, J P; Sutherland, J B; Walker, A E; Yang, Y; Cerniglia, C E

    1996-01-01

    When tested as a microbial model for mammalian drug metabolism, the filamentous fungus Cunninghamella elegans metabolized chlorpromazine and methdilazine within 72 h. The metabolites were extracted by chloroform, separated by high-performance liquid chromatography, and characterized by proton nuclear magnetic resonance, mass, and UV spectroscopic analyses. The major metabolites of chlorpromazine were chlorpromazine sulfoxide (36%), N-desmethylchlorpromazine (11%), N-desmethyl-7-hydroxychlorpromazine (6%), 7-hydroxychlorpromazine sulfoxide (36%), N-hydroxychlorpromazine (11%), 7-hydroxychlorpromazine sulfoxide (5%), and chlorpromazine N-oxide (2%), all of which have been found in animal studies. The major metabolites of methdilazine were 3-hydroxymethdilazine (3%). (18)O(2) labeling experiments indicated that the oxygen atoms in methdilazine sulfoxide, methdilazine N-oxide, and 3-hydroxymethdilazine were all derived from molecular oxygen. The production of methdilazine sulfoxide and 3-hydroxymethdilazine was inhibited by the cytochrome P-450 inhibitors metyrapone and proadifen. An enzyme activity for the sulfoxidation of methdilazine was found in microsomal preparations of C. elegans. These experiments suggest that the sulfoxidation and hydroxylation of methdilazine and chlorpromazine by C. elegans are catalyzed by cytochrome P-450. PMID:8975609

  13. A Bifunctional Dimethylsulfoxide Substitute Enhances the Aqueous Solubility of Small Organic Molecules

    PubMed Central

    Sprachman, Melissa M.

    2012-01-01

    Abstract An oxetane-substituted sulfoxide has demonstrated potential as a dimethylsulfoxide substitute for enhancing the dissolution of organic compounds with poor aqueous solubilities. This sulfoxide may find utility in applications of library storage and biological assays. For the model compounds studied, significant solubility enhancements were observed using the sulfoxide as a cosolvent in aqueous media. Brine shrimp, breast cancer (MDA-MB-231), and liver cell line (HepG2) toxicity data for the new additive are also presented, in addition to comparative IC50 values for a series of PKD1 inhibitors. PMID:22192308

  14. Removal of plutonium and Americium from hydrochloric acid waste streams using extraction chromatography

    SciTech Connect

    Schulte, L.D.; FitzPatrick, J.R.; Salazar, R.R.; Schake, B.S.; Martinez, B.T.

    1995-01-01

    Extraction chromatography is under development as a method to lower actinide activity levels in hydrochloric acid (HCl) effluent streams. Successful application of this technique for radioactive liquid waste treatment would provide a low activity feedstream for HCl recycle, reduce the loss of radioactivity to the environment in aqueous effluents, and lower the quantity and improve the form of solid waste generated. The extraction of plutonium and americium from HCl solutions was examined for several commercial and laboratory-produced sorbed resin materials. Polymer beads were coated with n-octyl(phenyl)-N,N-diisobutylcarbamoyl- methylphosphine oxide (CMPO) and either tributyl phosphate (TBP), or diamyl amylphosphonate (DAAP). Distribution coefficients for Pu and Am were measured by contact studies in 1-10 M HCl, while varying REDOX conditions, actinide loading levels, and resin formulations. Flow experiments were run to evaluate actinide loading and elution under varied conditions. Significant differences in the actinide distribution coefficients in contact experiments, and in actinide retention in flow experiments were observed as a function of resin formulation.

  15. Selective separation of uranyl ion from TRU`s in a combined solvent extraction process using tetrahydrofuran-2,3,4,5-tetracarboxylic acid

    SciTech Connect

    Nash, K.L.; Horwitz, E.P.; Diamond, H.; Rickert, P.G.; Muntean, J.V.; Mendoza, M.D.; Giuseppe, G. di

    1996-01-01

    Selective partitioning of uranyl from transuranic elements in a solvent extraction system which employs a neutral organophosphorus extractant and an aqueous complexant has been demonstrated in a previous report. The extractant solution combines octyl(phenyl)-N, N-diisobutylcarbamoylmethylphosphine oxide (CMPO), diamyl(amyl)phosphonate (or tributylphosphate), and di(t-butylcyclohexano)-18-crown-6 in Isopar L, and is designed for simultaneous removal of strontium, technetium, lanthanides and actinides from radioactive wastes. The aqueous complexant is tetrahydrofuran-2,3,4,5-tetracarboxylic acid (THFTCA). In this report, the separation of UO{sub 2}{sup 2+} from Np(IV), Eu(III), Am(III), and Pu(IV) using the Combined Process Solvent has been optimized. Potentiometric titration and NMR spectroscopic results describe the distribution of THFTCA into the organic phase as a function of acidity and [THFTCA]. Further potentiometric titration experiments have determined the stoichiometry and stability of uranyl complexes in the aqueous phase. The thermodynamic data indicate that the uranyl complexes are anomalously weak which partially accounts for the selectivity. Ternary complexes involving UO{sub 2}{sup 2+}, CMPO, and THFTCA in the extractant phase also appear to play a role. 13 refs., 6 figs., 1 tab.

  16. The design and use of a simple System Suitability Test Mix for generic reverse phase high performance liquid chromatography-mass spectrometry systems and the implications for automated system monitoring using global software tracking.

    PubMed

    Mutton, Ian; Boughtflower, Bob; Taylor, Nick; Brooke, Daniel

    2011-06-10

    The development of a seven-component test mixture designed for use with a generic gradient and a reversed-phase high performance liquid chromatography-mass spectrometry (RP-HPLC-MS) system is discussed. Unlike many test mixtures formulated in order to characterise column quality at neutral pH, the test mixture reported here was designed to permit an overall suitability assessment of the whole liquid chromatography-mass spectrometry (LCMS) system. The mixture is designed to test the chromatographic performance of the column as well as certain aspects of the performance of the individual instrumental components of the system. The System Suitability Test Mix can be used for low and high pH generic reverse phase LCMS analysis. Four phthalates are used: diethyl phthalate (DEP), diamyl phthalate (DAP), di-n-hexyl phthalate (DHP) and dioctyl phthalate (DOP). Three other probes are employed: 8-bromoguanosine (8-BG), amitryptyline (Ami), and 4-chlorocinnamic acid (4-CCA). We show that analysis of this test mixture can alert the user when any part of the system (instrument or column) contributes to loss of overall performance and may require remedial action and demonstrate that it can provide information that enables us to document data quality control. PMID:21543072

  17. A flowsheet concept for an Am/Ln separation based on Am{sup VI} solvent extraction

    SciTech Connect

    Mincher, B.J.; Law, J.D.

    2013-07-01

    The separation of Am from the lanthanides and curium is a key step in proposed advanced fuel cycle scenarios. The partitioning and transmutation of Am is desirable to minimize the long-term radiotoxicity of material interred in a future high-level waste repository. However, a separation amenable to process scale-up remains elusive. Higher oxidation states of americium have recently been used to demonstrate solvent extraction-based separations using conventional fuel cycle ligands. Here, the successful partitioning of Am{sup VI} from the bulk of lanthanides and curium using diamyl-amyl-phosphonate (DAAP) extraction is reported. Due to the instability of Am{sup VI} in the organic phase it was readily selectively stripped to a new acidic aqueous phase to provide separation from co-extracted Ce{sup IV}. The use of NaBiO{sub 3} as an oxidant to separate Am from the lanthanides and Cm by solvent extraction has been successfully demonstrated on the bench scale. Based on these results, flowsheet concepts can be designed that result in 96 % Am recovery in the presence of a few percent of the remaining Cm and the lanthanides in two extraction contacts. Preliminary results also indicate that the DAAP extractant is robust toward γ- irradiation under realistic conditions of acidity and dissolved oxygen concentration.

  18. Modulation of potassium channel function by methionine oxidation and reduction

    PubMed Central

    Ciorba, Matthew A.; Heinemann, Stefan H.; Weissbach, Herbert; Brot, Nathan; Hoshi, Toshinori

    1997-01-01

    Oxidation of amino acid residues in proteins can be caused by a variety of oxidizing agents normally produced by cells. The oxidation of methionine in proteins to methionine sulfoxide is implicated in aging as well as in pathological conditions, and it is a reversible reaction mediated by a ubiquitous enzyme, peptide methionine sulfoxide reductase. The reversibility of methionine oxidation suggests that it could act as a cellular regulatory mechanism although no such in vivo activity has been demonstrated. We show here that oxidation of a methionine residue in a voltage-dependent potassium channel modulates its inactivation. When this methionine residue is oxidized to methionine sulfoxide, the inactivation is disrupted, and it is reversed by coexpression with peptide methionine sulfoxide reductase. The results suggest that oxidation and reduction of methionine could play a dynamic role in the cellular signal transduction process in a variety of systems. PMID:9275229

  19. Effects of electron acceptors and radical scavengers on nonchain radical nucleophilic substitution reactions

    SciTech Connect

    Xianman Zhang; Dilun Yang; Youcheng Liu )

    1993-01-01

    The yields of reaction products from thermal nucleophilic substitution reactions in dimethyl sulfoxide (DMSO) of six o- and p-nitrohalobenzenes with the sodium salt of ethyl [alpha]-cyanoacetate carbanion [Na[sup +][sup [minus

  20. Tested Demonstrations.

    ERIC Educational Resources Information Center

    Gilbert, George L.

    1982-01-01

    Two demonstrations are described: (1) a sunset effect using a gooseneck lamp and 20 sheets of paper and (2) the preparation and determination of structural features of dimethyl sulfoxide (DMSO) by infrared spectroscopy. (SK)

  1. A new class of organocatalysts: sulfenate anions.

    PubMed

    Zhang, Mengnan; Jia, Tiezheng; Yin, Haolin; Carroll, Patrick J; Schelter, Eric J; Walsh, Patrick J

    2014-09-26

    Sulfenate anions are known to act as highly reactive species in the organic arena. Now they premiere as organocatalysts. Proof of concept is offered by the sulfoxide/sulfenate-catalyzed (1-10 mol%) coupling of benzyl halides in the presence of base to generate trans-stilbenes in good to excellent yields (up to 99%). Mechanistic studies support the intermediacy of sulfenate anions, and the deprotonated sulfoxide was determined to be the resting state of the catalyst. PMID:25111259

  2. The Epoxidation of Carbonyl Compounds with a Benzyne-Triggered Sulfur Ylide.

    PubMed

    Lou, Mei-Mei; Wang, Han; Song, Li; Liu, Hong-Yi; Li, Zhong-Qiu; Guo, Xiao-Shuang; Zhang, Fu-Geng; Wang, Bin

    2016-07-15

    An efficient method for the synthesis of epoxides from carbonyl compounds, sulfoxides, and benzyne is presented. The strategy involved an epoxidation by a sulfur ylide which is formed in situ from sulfoxide and benzyne through the S-O bond insertion and deprotonation. This one-pot reaction proceeds under mild and base-free conditions, providing a convenient way to introduce the substituted methylene groups onto the carbonyl carbon. PMID:27337065

  3. Photodeoxygenation of dinaphthothiophene, benzophenanthrothiophene, and benzonaphthothiophene S-oxides.

    PubMed

    Zheng, X; Baumann, S M; Chintala, S M; Galloway, K D; Slaughter, J B; McCulla, R D

    2016-06-01

    Photoinduced deoxygenation of dibenzothiophene S-oxide (DBTO) has been suggested to release atomic oxygen [O((3)P)]. To expand the conditions and applications where O((3)P) could be used, generation of O((3)P) at longer wavelengths was desirable. The sulfoxides benzo[b]naphtho-[1,2,d]thiophene S-oxide, benzo[b]naphtho[2,1,d]thiophene S-oxide, benzo[b]phenanthro[9,10-d]thiophene S-oxide, dinaphtho[2,1-b:1',2'-d]thiophene S-oxide, and dinaphtho[1,2-b:2',1'-d]thiophene S-oxide all absorb light at longer wavelengths than DBTO. To determine if these sulfoxides could be used to generate O((3)P), quantum yield studies, product studies, and computational analysis were performed. Quantum yields for the deoxygenation were up to 3 times larger for these sulfoxides compared to DBTO. However, oxidation of the solvent by these sulfoxides resulted in different ratios of oxidized products compared to DBTO, which suggested a change in deoxygenation mechanism. Density functional calculations revealed a much larger singlet-triplet gap for the larger sulfoxides compared to DBTO. This led to the conclusion that the examined sulfoxides could undergo deoxygenation by two different mechanisms. PMID:27200438

  4. The participation of human hepatic P450 isoforms, flavin-containing monooxygenases and aldehyde oxidase in the biotransformation of the insecticide fenthion

    SciTech Connect

    Leoni, Claudia; Buratti, Franca M. Testai, Emanuela

    2008-12-01

    Although fenthion (FEN) is widely used as a broad spectrum insecticide on various crops in many countries, very scant data are available on its biotransformation in humans. In this study the in vitro human hepatic FEN biotransformation was characterized, identifying the relative contributions of cytochrome P450 (CYPs) and/or flavin-containing monooxygenase (FMOs) by using single c-DNA expressed human enzymes, human liver microsomes and cytosol and CYP/FMO-specific inhibitors. Two major metabolites, FEN-sulfoxide and FEN-oxon (FOX), are formed by some CYPs although at very different levels, depending on the relative CYP hepatic content. Formation of further oxidation products and the reduction of FEN-sulfoxide back to FEN by the cytosolic aldehyde oxidase enzyme were ruled out. Comparing intrinsic clearance values, FOX formation seemed to be favored and at low FEN concentrations CYP2B6 and 1A2 are mainly involved in its formation. At higher levels, a more widespread CYP involvement was evident, as in the case of FEN-sulfoxide, although a higher efficiency of CYP2C family was suggested. Hepatic FMOs were able to catalyze only sulfoxide formation, but at low FEN concentrations hepatic FEN sulfoxidation is predominantly P450-driven. Indeed, the contribution of the hepatic isoforms FMO{sub 3} and FMO{sub 5} was generally negligible, although at high FEN concentrations FMO's showed activities comparable to the active CYPs, accounting for up to 30% of total sulfoxidation. Recombinant FMO{sub 1} showed the highest efficiency with respect to CYPs and the other FMOs, but it is not expressed in the adult human liver. This suggests that FMO{sub 1}-catalysed sulfoxidation may represent the major extra-hepatic pathway of FEN biotransformation.

  5. Antiandrogenic activity and metabolism of the organophosphorus pesticide fenthion and related compounds.

    PubMed Central

    Kitamura, Shigeyuki; Suzuki, Tomoharu; Ohta, Shigeru; Fujimoto, Nariaki

    2003-01-01

    We investigated the endocrine-disrupting actions of the organophosphorus pesticide fenthion and related compounds and the influence of metabolic transformation on the activities of these compounds. Fenthion acted as an antagonist of the androgenic activity of dihydrotestosterone (10(-7)M) in the concentration range of 10(-6)-10(-4)M in an androgen-responsive element-luciferase reporter-responsive assay using NIH3T3 cells. The antiandrogenic activity of fenthion was similar in magnitude to that of flutamide. Fenthion also tested positive in the Hershberger assay using castrated male rats. Marked estrogenic and antiestrogenic activities of fenthion and related compounds were not observed in MCF-7 cells. When fenthion was incubated with rat liver microsomes in the presence of NADPH, the antiandrogenic activity markedly decreased, and fenthion sulfoxide was detected as a major metabolite. The oxidase activity toward fenthion was exhibited by cytochrome P450 and flavin-containing monooxygenase. Fenthion sulfoxide was negative in the screening test for antiandrogens, as was fenthion sulfone. However, when fenthion sulfoxide was incubated with liver cytosol in the presence of 2-hydroxypyrimidine, an electron donor of aldehyde oxidase, the extract of the incubation mixture exhibited antiandrogenic activity. In this case, fenthion was detected as a major metabolite of the sulfoxide. Metabolic interconversion between fenthion and fenthion sulfoxide in the body seems to maintain the antiandrogenic activity. PMID:12676606

  6. Oxidation of sulfur compounds in petroleum residues: reactivity-structural relationships

    SciTech Connect

    Petersen, J.C.; Dorrence, S.M.; Nazir, M.; Plancher, H.; Barbour, F.A.

    1981-09-01

    Studies have been made on the reactivity of sulfur entities in oxidized asphalts and oxidized petroleum distillation residues during air oxidation. Asphalts are referred to as residues. The oxidation of these materials includes the rapid formation of an unsymmetrical ir band at ca 1030/cm. Sulfoxides are not normally found in unoxidized petroleum residues, but develop rapidly during air aging. Their presence in these residues has been inferred from their specific bands in ir spectra. Confirmation of sulfoxides was obtained from deoxygenation with chlorocarbenes and decomposition with bromine and peracetic acid. Hydroperoxides in amounts that might interfere with sulfoxide determination were not found in oxidated residues. The concentration of sulfoxides formed during air oxidation was found to rapidly reach a maximum value and to remain constant on further oxidation of the residue. Model studies indicate that hydroperoxides play a role in sulfoxide formation. The data show that both alkyl and aryl sulfides were present in aliphatic residues, that predominantly alkyl types were oxidized during oxidative aging in air and that concentrations of the alkyl and aryl types vary with crude source. Peracetic acid oxidation of the residues indicated that most of the sulfur present was in the form of sulfides. 2 figures, 6 tables.

  7. Investigation of structure-activity relationships in organophosphates-cholinesterase interaction using docking analysis.

    PubMed

    Moralev, Serge N; Tikhonov, Denis B

    2010-09-01

    It is known than the most potent homologues in various series of O,O-dialkylphosphates are the dibutyl or diamyl derivatives toward mammalian cholinesterases (ChEs) (both Acetyl- and Butyryl-ChEs), and the dimethyl or diethyl ones toward insect AChEs. To investigate the ChE interaction with organophosphorus inhibitors (OPIs) in more detail, we have performed in silico docking of the series of O,O-dialkylfluorophosphates into active center of different ChEs - both from mammals (human and mouse AChEs and horse BChE), and from insects (spring grain aphid AChE belonging to AChE-1 type, and housefly AChE belonging to AChE-2 type). According to the modeling results, one radical is directed to the anionic site W84, another to the acyl pocket. In addition to well-known residues 288 and 290 (Torpedo AChE sequence numbering), we showed an essential influence of residue 400 - a short alkyl residue in mammalian ChEs and phenylalanine in insect ChEs. Phenylalanine in this position creates sterical hindrance for proper orientation of the OPI molecule, which increases the distance between the catalytic serine gamma-oxygen and phosphorus, and decreases the angle of nucleophylic attack. This suggestion was supported by docking of dibutylfluorophosphate into the active center of AChEs with in silico mutations. Thus, we suggest both the angle of nucleophylic attack and the distance between the catalytic serine and phosphorus atom as measures of productivity of OPI binding. PMID:20347727

  8. Extraction of alkaline earth and actinide cations by mixtures of Di(2-ethylhexyl)alkylenediphosphonic acids and neutral synergists.

    SciTech Connect

    McAlister, D. R.; Chiarizia, R.; Dietz, M. L.; Herlinger, A. W.; Zalupski, P. R.; Chemistry; Loyola Univ.

    2002-09-18

    The synergistic extraction of alkaline earth (Ca{sup 2+}, Sr{sup 2+}, Ba{sup 2+} and Ra{sup 2+}) and actinide (Am{sup 3+}, UO{sub 2}{sup 2+} and Th{sup 4+}) cations from aqueous nitric acid solutions by mixtures of P,P'-di(2-ethylhexyl) methylene-(H{sub 2}DEH[MDP]), ethylene-(H{sub 2}DEH[EDP]), and butylene-(H{sub 2}DEH[BuDP]) diphosphonic acids and neutral extractants in o-xylene has been investigated. The cis-syn-cis and cis-anti-cis stereoisomers of dicyclohexano-18-crown-6 (DCH18C6), the unsubstituted 21-crown-7 (21C7) and dicyclohexano-21-crown-7 (DCH21C7) were used as neutral synergists of the crown ether type. For Am(III) synergistic effects were also investigated using neutral organophosphorus esters, such as, tri-n-butylphosphate (TBP), diamyl amylphosphonate (DA[AP]) and tri-n-octylphosphine oxide (TOPO) as co-extractants. In all systems investigated, no synergistic extraction enhancement was observed for actinide ions. For the alkaline earth cations, synergistic effects were only observed when mixtures of H{sub 2}DEH[EDP] or H{sub 2}DEH-[BuDP] with DCH18C6 were used to extract Sr{sup 2+}, Ba{sup 2+} and Ra{sup 2+}. No synergistic effects were observed for the extraction of alkaline earth cations by H{sub 2}DEH[MDP] or for the extraction of Ca{sup 2+} by any of the diphosphonic acids studied. The synergistic effects obtained with DCH18C6 were significantly higher for the cis-syn-cis than for the cis-anti-cis stereoisomer.

  9. Dibenzyl Sulfide Metabolism by White Rot Fungi

    PubMed Central

    Van Hamme, Jonathan D.; Wong, Eddie T.; Dettman, Heather; Gray, Murray R.; Pickard, Michael A.

    2003-01-01

    Microbial metabolism of organosulfur compounds is of interest in the petroleum industry for in-field viscosity reduction and desulfurization. Here, dibenzyl sulfide (DBS) metabolism in white rot fungi was studied. Trametes trogii UAMH 8156, Trametes hirsuta UAMH 8165, Phanerochaete chrysosporium ATCC 24725, Trametes versicolor IFO 30340 (formerly Coriolus sp.), and Tyromyces palustris IFO 30339 all oxidized DBS to dibenzyl sulfoxide prior to oxidation to dibenzyl sulfone. The cytochrome P-450 inhibitor 1-aminobenzotriazole eliminated dibenzyl sulfoxide oxidation. Laccase activity (0.15 U/ml) was detected in the Trametes cultures, and concentrated culture supernatant and pure laccase catalyzed DBS oxidation to dibenzyl sulfoxide more efficiently in the presence of 2,2′-azinobis(3-ethylbenzthiazoline-6-sulfonate) (ABTS) than in its absence. These data suggest that the first oxidation step is catalyzed by extracellular enzymes but that subsequent metabolism is cytochrome P-450 mediated. PMID:12571066

  10. Synthesis and oxidation of some azole-containing thioethers

    PubMed Central

    Chernova, Nina P; Ogorodnikov, Vladimir D; Petrenko, Tatiana V

    2011-01-01

    Summary Pyrazole and benzotriazole-containing thioethers, namely 1,5-bis(3,5-dimethylpyrazol-1-yl)-3-thiapentane, 1,8-bis(3,5-dimethylpyrazol-1-yl)-3,6-dithiaoctane and 1,3-bis(1,2,3-benzotriazol-1-yl)-2-thiapropane were prepared and fully characterized. Oxidation of the pyrazole-containing thioether by hydrogen peroxide proceeds selectively to provide a sulfoxide or sulfone, depending on the amount of oxidant used. Oxidation of the benzotriazole derivative by hydrogen peroxide is not selective, and sulfoxide and sulfone form concurrently. Selenium dioxide-catalyzed oxidation of benzotriazole thioether by H2O2, however, proceeds selectively and yields sulfoxide only. PMID:22238528

  11. Carbon-carbon bond-forming reactions of α-thioaryl carbonyl compounds for the synthesis of complex heterocyclic molecules.

    PubMed

    Biggs-Houck, James E; Davis, Rebecca L; Wei, Jingqiang; Mercado, Brandon Q; Olmstead, Marilyn M; Tantillo, Dean J; Shaw, Jared T

    2012-01-01

    Strategies for the formation of carbon-carbon bonds from the α-thioaryl carbonyl products of substituted lactams are described. Although direct functionalization is possible, a two step process of oxidation and magnesium-sulfoxide exchange has proven optimal. The oxidation step results in the formation of two diastereomers that exhibit markedly different levels of stability toward elimination, which is rationalized on the basis of quantum mechanical calculations and X-ray crystallography. Treatment of the sulfoxide with i-PrMgCl results in the formation of a magnesium enolate that will undergo an intramolecular Michael addition reaction to form two new stereogenic centers. The relationship between the substitution patterns of the sulfoxide substrate and the efficiency of the magnesium exchange reaction are also described. PMID:22023077

  12. Aerobic Linear Allylic C-H Amination: Overcoming Benzoquinone Inhibition.

    PubMed

    Pattillo, Christopher C; Strambeanu, Iulia I; Calleja, Pilar; Vermeulen, Nicolaas A; Mizuno, Tomokazu; White, M Christina

    2016-02-01

    An efficient aerobic linear allylic C-H amination reaction is reported under palladium(II)/bis-sulfoxide/Brønsted base catalysis. The reaction operates under preparative, operationally simple conditions (1 equiv of olefin, 1 atm O2 or air) with reduced Pd(II)/bis-sulfoxide catalyst loadings while providing higher turnovers and product yields than systems employing stoichiometric benzoquinone (BQ) as the terminal oxidant. Pd(II)/BQ π-acidic interactions have been invoked in various catalytic processes and are often considered beneficial in promoting reductive functionalizations. When such electrophilic activation for functionalization is not needed, however, BQ at high concentrations may compete with crucial ligand (bis-sulfoxide) binding and inhibit catalysis. Kinetic studies reveal an inverse relationship between the reaction rate and the concentration of BQ, suggesting that BQ is acting as a ligand for Pd(II) which results in an inhibitory effect on catalysis. PMID:26730458

  13. Pharmacokinetics of albendazole in sheep.

    PubMed

    Marriner, S E; Bogan, J A

    1980-07-01

    The concentrations of albendazole and its two major metabolites, the sulfoxide and sulfone, were measured in plasma and in ruminal and abomasal fluid of three sheep (surgically prepared with permanent ruminal and abomasal cannulae) orally given albendazole as a suspension at a dose rate of 10 mg/kg. Albendazole was not detectable in plasma at any time in one sheep (detection limit, 0.02 micrograms/ml) and in the other sheep, only transiently detectable. Albendazole sulfoxide was detectable in plasma and in abomasal fluid at mean peak concentrations of 3.2 and 26.2 micrograms/ml, respectively, 20 hours after administration. It is probable that much of the anthelmintic activity of albendazole in sheep is due to the metabolically formed sulfoxide and sulfone. PMID:7436109

  14. Determination of mepitiostane metabolites in human urine by liquid chromatography/tandem mass spectrometry for sports drug testing.

    PubMed

    Okano, Masato; Sato, Mitsuhiko; Kojima, Asami; Kageyama, Shinji

    2015-11-10

    Mepitiostane (2α,3α-epithio-17β-(1-methoxycyclopentyloxy)-5α-androstane), which is a prodrug of epitiostanol (2α,3α-epitio-5α-androstane-17β-ol), is an epitiosteroid having anti-estrogenic and weak androgenic anabolic activities. The World Anti-Doping Agency prohibits the misuse of mepitiostane by athletes. Detection of the urinary metabolites epitiostanol sulfoxide and epitiostanol was studied using liquid chromatography/mass spectrometry (LC-MS) for doping control purposes. The use of LC-MS provided advantages over gas chromatography/mass spectrometry for detecting heat labile steroids because epitiostanol and epitiostanol sulfoxide were primarily pyrolized to 5α-androst-2-en-17β-ol. The method consists of enzymatic hydrolysis using β-glucuronidase (Escherichia coli), liquid-liquid extraction, and subsequent ultra-performance liquid chromatography/electrospray-tandem mass spectrometry. Epitiostanol sulfoxide was determined at urinary concentrations of 0.5-50ng/mL, recovery was 76.2-96.9%, and assay precision was calculated as 0.9-1.7% (intra-day) and 2.0-6.6% (inter-day). Epitiostanol was determined at urinary concentrations of 0.5-50ng/mL, recovery was 26.1-35.6% and assay precision was calculated as 4.1-4.6% (intra-day) and 3.3-8.5% (inter-day). The limits of detection for epitiostanol sulfoxide and epitiostanol were 0.05ng/mL and 0.10ng/mL, respectively. Epitiostanol sulfoxide and epitiostanol, as their gluco-conjugates, were identified in human urine after oral administration of 10mg mepitiostane. Epitiostanol sulfoxide and epitiostanol could be detected up to 48h and 24h after administration, respectively. The results showed that the detection window of epitiostanol is much shorter than that of epitiostanol sulfoxide. The LC-MS detection of urinary epitiostanol sulfoxide, a specific metabolite with a sulphur atom in its molecular structure, is likely to be able to identify the abuse of mepitiostane. PMID:26247800

  15. Lithium/Element Exchange as an Efficient Tool for Accessing Atropo-enriched Biaryls via Arynes.

    PubMed

    Panossian, Armen; Leroux, Frédéric R

    2016-01-01

    This account documents the development of transition metal-free, aryne-mediated aryl-aryl coupling, the 'ARYNE coupling', which began in 2001 in Lausanne. ortho,ortho'-Di-, tri- and even tetrasubstituted biphenyls have now become accessible on a multi-gram scale. The reaction is perfectly regioselective and the obtained polybromobiphenyls can be submitted to regioselective bromine/lithium interconversions. The access to enantiopure biphenyls is now possible using enantiopure sulfoxides as chiral auxiliaries, which allow for subsequent chemoselective sulfoxide/metal exchange on each atropo-diastereoisomer with configurational stability of the intermediate biaryllithiums. Direct atropo-diastereoselective ARYNE coupling has been reported more recently. PMID:26931216

  16. POSSIBLE LINK BETWEEN METHIONINE OXIDATION AND PROTEIN PHOSPHORYLATION

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Aerobic metabolism leads to the production of reactive oxygen species that may damage proteins. Methionine residues in proteins are particularly susceptible to oxidation to methionine sulfoxide (MetSO) converting its side chain from hydrophobic to hydrophilic. We postulated that this could have a si...

  17. Enrichment of 3-nitro-1-propionic acid-metabolizing bacteria in avian feces

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Denitrobacterium detoxificans is a Gram-positive anaerobe that conserves energy for growth exclusively via anaerobic respiration, oxidizing H2, formate or lactate for the reduction of nitrate, trimethylamine oxide, dimethyl sulfoxide or nitroalkanes such as 3-nitro-1-propionic acid (NPA). At presen...

  18. Tested Demonstrations: Spectroscopy Illustrated.

    ERIC Educational Resources Information Center

    Gilbert, George L., Ed.

    1983-01-01

    Background information and procedures are provided for an experiment to prepare three metal derivatives of dimethyl sulfoxide (DMSO) and to determine some structural features of these derivatives based on their infrared spectra. Results and discussion of reactions involved are also provided. (JN)

  19. Use of Glycerol as an Optical Clearing Agent for Enhancing Photonic Transference and Detection of Salmonella typhimurium Through Porcine Skin

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The objective of this study was to evaluate glycerol (GLY) and GLY + dimethyl sulfoxide (DMSO) to increase photonic detection of transformed Salmonella typhimurium (S. typh-lux) through porcine skin. Skin was placed on 96-well plates containing S. typh-lux, imaged (5 min) using a CCD camera, and the...

  20. DMSO, Hobby Shops and the FDA: The Diffusion of a Health Policy Dilemma.

    ERIC Educational Resources Information Center

    Weinstock, Edward; Davis, Phillip

    1985-01-01

    Despite being banned by the FDA, DMSO (dimethyl sulfoxide) usage has spread rapidly among arthritic victims and weekend athletes. This study looked at current and past users to learn how they discovered DMSO, their reactions to buying an illegal drug, and possible implications for public health policy. (MT)

  1. USE OF GLYCEROL AS AN OPTICAL CLEARING AGENT FOR ENHANCING PHOTONIC TRANSFERENCE AND DETECTIONOF SALMONELLA TYPHIMURIUM THROUGH PORCINE SKIN

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The objective of this study was to evaluate glycerol (GLY) and GLY+DMSO (dimethyl sulfoxide) to increase photonic detection of transformed Salmonella typhimurium (S.typh-Lux) through porcineskin. A 96-well plate containing S. typh-lux was imaged for 5 min as a control reference usinga CCD camera. Sk...

  2. Gelled Anti-icing Agents

    NASA Technical Reports Server (NTRS)

    Markles, O. F.; Sperber, H. H.

    1983-01-01

    Pectin added to antifreeze/water mixture. Formulations include water with dimethyl sulfoxide (DMSO) as deicer and pectin as gel former. Without gelling agent, deicer runs off vertical surfaces. Without pectin solution will completely evaporate in far less time. Agents developed have wide potential for ice prevention on runways, highways, bridges and sidewalks.

  3. Use of Glycerol as an Optical Clearing Agent for Enhancing Photonic Transference and Detection of Salmonella typhimurium through Porcine Skin

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The objective of this study was to evaluate glycerol (GLY) and GLY + dimethyl sulfoxide (DMSO) to increase photonic detection of transformed Salmonella typhimurium (S. typh-lux) through porcine skin. Skin was placed on 96-well plates containing S. typh-lux, imaged (5 min) using a CCD camera, and the...

  4. Microbial Flavoprotein Monooxygenases as Mimics of Mammalian Flavin-Containing Monooxygenases for the Enantioselective Preparation of Drug Metabolites.

    PubMed

    Gul, Turan; Krzek, Marzena; Permentier, Hjalmar P; Fraaije, Marco W; Bischoff, Rainer

    2016-08-01

    Mammalian flavin-containing monooxygenases, which are difficult to obtain and study, play a major role in detoxifying various xenobiotics. To provide alternative biocatalytic tools to generate flavin-containing monooxygenases (FMO)-derived drug metabolites, a collection of microbial flavoprotein monooxygenases, sequence-related to human FMOs, was tested for their ability to oxidize a set of xenobiotic compounds. For all tested xenobiotics [nicotine, lidocaine, 3-(methylthio)aniline, albendazole, and fenbendazole], one or more monooxygenases were identified capable of converting the target compound. Chiral liquid chromatography with tandem mass spectrometry analyses of the conversions of 3-(methylthio)aniline, albendazole, and fenbendazole revealed that the respective sulfoxides are formed in good to excellent enantiomeric excess (e.e.) by several of the tested monooxygenases. Intriguingly, depending on the chosen microbial monooxygenase, either the (R)- or (S)-sulfoxide was formed. For example, when using a monooxygenase from Rhodococcus jostii the (S)-sulfoxide of albendazole (ricobendazole) was obtained with a 95% e.e. whereas a fungal monooxygenase yielded the respective (R)-sulfoxide in 57% e.e. For nicotine and lidocaine, monooxygenases could be identified that convert the amines into their respective N-oxides. This study shows that recombinantly expressed microbial monooxygenases represent a valuable toolbox of mammalian FMO mimics that can be exploited for the production of FMO-associated xenobiotic metabolites. PMID:26984198

  5. Chiral DHIP-Based Metal-Organic Frameworks for Enantioselective Recognition and Separation.

    PubMed

    Zhang, Jie; Li, Zijian; Gong, Wei; Han, Xing; Liu, Yan; Cui, Yong

    2016-08-01

    Two chiral porous 2,3-dihydroimidazo[1,2-a]pyridine (DHIP)-based metal-organic frameworks (MOFs) are assembled from an enantiopure dipyridyl-functionalized DHIP bridging ligand. The Zn-DHIP MOF shows a good enantioseparation performance toward aromatic sulfoxides, and the heterogeneous adsorbent can be readily recovered and reused without significant degradation of the separation performance. PMID:27227785

  6. 40 CFR Appendix A to Part 439 - Tables

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 30 2014-07-01 2014-07-01 false Tables A Appendix A to Part 439... (CONTINUED) PHARMACEUTICAL MANUFACTURING POINT SOURCE CATEGORY Pt. 439, App. A Appendix A to Part 439—Tables... Cellosolve Dimethyl Sulfoxide 1 These parameters may be used as a surrogate to represent other parameters...

  7. Accelerated Degradation of Aldicarb and Its Metabolites in Cotton Field Soils

    PubMed Central

    Lawrence, K. S.; Feng, Yucheng; Lawrence, G. W.; Burmester, C. H.; Norwood, S. H.

    2005-01-01

    The degradation of aldicarb, and the metabolites aldicarb sulfoxide and aldicarb sulfone, was evaluated in cotton field soils previously exposed to aldicarb. A loss of efficacy had been observed in two (LM and MS) of the three (CL) field soils as measured by R. reniformis population development and a lack of cotton yield response. Two soils were compared for the first test—one where aldicarb had been effective (CL) and the second where aldicarb had lost its efficacy (LM). The second test included all three soils: autoclaved, non-autoclaved and treated with aldicarb at 0.59 kg a.i./ha, or not treated with aldicarb. The degradation of aldicarb to aldicarb sulfoxide and then to aldicarb sulfone was measured using high-performance liquid chromatography (HPLC) in both tests. In test one, total degradation of aldicarb and its metabolites occurred within 12 days in the LM soil. Aldicarb sulfoxide and aldicarb sulfone were both present in the CL soil at the conclusion of the test at 42 days after aldicarb application. Autoclaving the LM and MS soils extended the persistence of the aldicarb metabolites as compared to the same soils not autoclaved. The rate of degradation was not changed when the CL natural soil was autoclaved. The accelerated degradation was due to more rapid degradation of aldicarb sulfoxide and appears to be biologically mediated. PMID:19262860

  8. Coupling of Dimethylsulfide Oxidation to Biomass Production by a Marine Flavobacterium▿

    PubMed Central

    Green, David H.; Shenoy, Damodar M.; Hart, Mark C.; Hatton, Angela D.

    2011-01-01

    Dimethylsulfide (DMS) is an important climatically active gas. In the sea, DMS is produced primarily by microbial metabolism of the compatible solute dimethylsulfoniopropionate. Laboratory growth of Bacteroidetes with DMS resulted in its oxidation to dimethyl sulfoxide but only in the presence of glucose. We hypothesized that electrons liberated from sulfur oxidation were used to augment biomass production. PMID:21378049

  9. Coupling Oxidative Signals to Protein Phosphorylation via Methionine Oxidation in Arabidopsis

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The mechanisms involved in sensing oxidative signaling molecules such as H2O2 in plant and animal cells are not completely understood. In the present study, we tested the postulate that oxidation of methionine (Met) to Met sulfoxide (MetSO) can couple oxidative signals to changes in protein phosphor...

  10. Convergent signaling pathways – interaction between methionine oxidation and serine/threonine/tyrosine O-phosphorylation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Oxidation of Methionine (Met) to Met sulfoxide (MetSO) is a frequently found reversible post-translational modification. It has been presumed that the major functional role for oxidation-labile Met residues is to protect proteins/cells from oxidative stress. However, Met oxidation has been establi...

  11. MONITORING THE AIR FOR TOXIC AND GENOTOXIC COMPOUNDS

    EPA Science Inventory

    A time-integrated sampling system interfaced with a toxicity-based assay is reported for monitoring volatile toxic industrial chemicals (TICs). Semipermeable membrane devices (SPMDs) using dimethyl sulfoxide (DMSO) as the fill solvent accumulated each of 17 TICs from the vapor p...

  12. VAPOR SAMPLING DEVICE FOR INTERFACE WITH MICROTOX ASSAY FOR SCREENING TOXIC INDUSTRIAL CHEMICALS

    EPA Science Inventory

    A time-integrated sampling system interfaced with a toxicity-based assay is reported for monitoring volatile toxic industrial chemicals (TICs). Semipermeable membrane devices (SPMDs) using dimethyl sulfoxide (DMSO) as the fill solvent accumulated each of 17 TICs from the vapor...

  13. Oxidation of methionine residues in proteins of activated human neutrophils.

    PubMed Central

    Fliss, H; Weissbach, H; Brot, N

    1983-01-01

    A simple assay for the detection of 35S-labeled methionine sulfoxide residues in proteins is described. The assay, which is based on the ability of CNBr to react with methionine but not with methionine sulfoxide, requires the prelabeling of cellular proteins with [35S]methionine. The assay was used to study the extent of methionine oxidation in newly synthesized proteins of both activated and quiescent human neutrophils. In cells undergoing a phorbol 12-myristate 13-acetate-induced respiratory burst, about 66% of all methionine residues in newly synthesized proteins were oxidized to the sulfoxide derivative, as compared with 9% in cells not treated with the phorbol ester. In contrast, quantitation of methionine sulfoxide content in the total cellular protein by means of amino acid analysis showed that only 22% of all methionine residues were oxidized in activated cells as compared with 9% in quiescent cells. It is proposed that methionine residues in nascent polypeptide chains are more susceptible to oxidation than those in completed proteins. PMID:6580633

  14. COMPATIBILITY OF ORGANIC SOLVENTS WITH THE MICROSCREEN PROPHAGE-INDUCTION ASSAY: SOLVENT-MUTAGEN INTERACTIONS

    EPA Science Inventory

    The following solvents did not induce prophage lambda in the Escherichia coli WP2 s (Microscreen assay: cetone, benzene, chloroform, ethanol, n-hexane, isopropanol methanol, toluene, and a mixture of the three isomers of xylene. imethyl sulfoxide was genotoxic in the presence and...

  15. Modified Antifreeze Liquids for Use on Surfaces

    NASA Technical Reports Server (NTRS)

    Lynn, R. O.

    1983-01-01

    Report presents results of evaluation of two antifreeze liquids, dimethyl sulfoxide and ethylene glycol and five viscosity modifiers: gelatin, gum tragacanth, starch, agarose powder and citrus pectin. Purpose of evaluation to find best way of dealing with frost formation on Space Shuttle.

  16. Mutagenicity of fly ash particles in Paramecium

    SciTech Connect

    Smith-Sonneborn, J.; Palizzi, R.A.; Herr, C.; Fisher, G.L.

    1981-01-09

    Paramecium, a protozoan that ingests nonnutritive particulate matter, was used to determine the mutagenicity of fly ash. Heat treatment inactivated mutagens that require metabolic conversion to their active form but did not destroy all mutagenicity. Extraction of particles with hydrochloric acid, but not dimethyl sulfoxide, removed detectable mutagenic activity.

  17. Synthesis of an Albendazole Metabolite: Characterization and HPLC Determination

    ERIC Educational Resources Information Center

    Mahler, Graciela; Davyt, Danilo; Gordon, Sandra; Incerti, Marcelo; Nunez, Ivana; Pezaroglo, Horacio; Scarone, Laura; Serra, Gloria; Silvera, Mauricio; Manta, Eduardo

    2008-01-01

    In this laboratory activity, students are introduced to the synthesis of an albendazole metabolite obtained by a sulfide oxidation reaction. Albendazole as well as its metabolite, albendazole sulfoxide, are used as anthelmintic drugs. The oxidation reagent is H[subscript 2]O[subscript 2] in acetic acid. The reaction is environmental friendly,…

  18. Oxidation of an Adjacent Methionine Residue Inhibits Regulatory Seryl-phosphorylation of Pyruvate Dehydrogenase

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A Met residue is located adjacent to phosphorylation site 1 in the sequences of mitochondrial pyruvate dehydrogenase E1alpha subunits. When synthetic peptides including site 1 were treated with Hydrogen peroxide, the Met residue was oxidized to methionine sulfoxide (MetSO), and the peptides were no...

  19. A novel cysteine desulfurase influencing organosulfur compounds in Lentinula edodes

    PubMed Central

    Liu, Ying; Lei, Xiao-Yu; Chen, Lian-Fu; Bian, Yin-Bing; Yang, Hong; Ibrahim, Salam A.; Huang, Wen

    2015-01-01

    Organosulfur compounds are the basis for the unique aroma of Lentinula edodes, and cysteine sulfoxide lyase (C-S lyase) is the key enzyme in this trait. The enzyme from Alliium sativum has been crystallized and well-characterized; however, there have been no reports of the characterization of fungi C-S lyase at the molecular level. We identified a L. edodes C-S lyase (Lecsl), cloned a gene of Csl encoded Lecsl and then combined modeling, simulations, and experiments to understand the molecular basis of the function of Lecsl. Our analysis revealed Lecsl to be a novel cysteine desulfurase and not a type of cysteine sulfoxide lyase. The pyridoxal-5-phosphate (PLP) molecule bonded tightly to Lecsl to form a Lecsl-PLP complex. Moreover, the Lecsl had one active center that served to bind two kinds of substrates, S-methyl-L-cysteine sulfoxide and L-cysteine, and had both cysteine sulfoxide lyase and cysteine desulfurase activity. We found that the amino acid residue Asn393 was essential for the catalytic activity of Lecsl and that the gene Csl encoded a novel cysteine desulfurase to influence organosulfur compounds in L. edodes. Our results provide a new insight into understanding the formation of the unique aroma of L. edodes. PMID:26054293

  20. YTTRIUM-89 NMR: A POSSIBLE SPIN RELAXATION PROBE FOR STUDYING METAL ION INTERACTIONS WITH ORGANIC LIGANDS

    EPA Science Inventory

    The spin-lattice relaxation mechanisms for aqueous and dimethyl sulfoxide solutions of Y(NO3)3 have been found to be mainly spin-rotation and dipolar relaxation with solvent protons, unlike most heavy spin=1/2 metal ions which are relaxed mainly by spin-rotation and chemical shif...

  1. Synthesis of 3-Substituted Aryl[4,5]isothiazoles through an All-Heteroatom Wittig-Equivalent Process.

    PubMed

    Xu, Fanghui; Chen, Yuan; Fan, Erkang; Sun, Zhihua

    2016-06-01

    Extending the previous use of tert-butyl sulfoxide as the sulfinyl source, intramolecular sulfinylation of sulfonamides was successfully performed. The resulting sulfinimides were not isolated and instead were believed to go through an all-heteroatom Wittig-equivalent process to eventually afford aryl[4,5]isothiazoles in high yields. PMID:27215807

  2. Functional keratin as structural platforms

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Wool with up to 95% keratin by weight is a rich and pure source of proteinous biomaterial. As polymeric polyamide it exhibits high functionality through amide, carboxyl, sulfoxide, sulfide, and thiosulfide functions. Solubilized wool was transformed into keratin morphologies with the unique characte...

  3. Characterization of Bacillus thuringiensis l-Isoleucine Dioxygenase for Production of Useful Amino Acids▿†

    PubMed Central

    Hibi, Makoto; Kawashima, Takashi; Kodera, Tomohiro; Smirnov, Sergey V.; Sokolov, Pavel M.; Sugiyama, Masakazu; Shimizu, Sakayu; Yokozeki, Kenzo; Ogawa, Jun

    2011-01-01

    We determined the enzymatic characteristics of an industrially important biocatalyst, α-ketoglutarate-dependent l-isoleucine dioxygenase (IDO), which was found to be the enzyme responsible for the generation of (2S,3R,4S)-4-hydroxyisoleucine in Bacillus thuringiensis 2e2. Depending on the amino acid used as the substrate, IDO catalyzed three different types of oxidation reactions: hydroxylation, dehydrogenation, and sulfoxidation. IDO stereoselectively hydroxylated several hydrophobic aliphatic l-amino acids, as well as l-isoleucine, and produced (S)-3-hydroxy-l-allo-isoleucine, 4-hydroxy-l-leucine, (S)-4-hydroxy-l-norvaline, 4-hydroxy-l-norleucine, and 5-hydroxy-l-norleucine. The IDO reaction product of l-isoleucine, (2S,3R,4S)-4-hydroxyisoleucine, was again reacted with IDO and dehydrogenated into (2S,3R)-2-amino-3-methyl-4-ketopentanoate, which is also a metabolite found in B. thuringiensis 2e2. Interestingly, IDO catalyzed the sulfoxidation of some sulfur-containing l-amino acids and generated l-methionine sulfoxide and l-ethionine sulfoxide. Consequently, the effective production of various modified amino acids would be possible using IDO as the biocatalyst. PMID:21821743

  4. Characterization of Bacillus thuringiensis L-isoleucine dioxygenase for production of useful amino acids.

    PubMed

    Hibi, Makoto; Kawashima, Takashi; Kodera, Tomohiro; Smirnov, Sergey V; Sokolov, Pavel M; Sugiyama, Masakazu; Shimizu, Sakayu; Yokozeki, Kenzo; Ogawa, Jun

    2011-10-01

    We determined the enzymatic characteristics of an industrially important biocatalyst, α-ketoglutarate-dependent l-isoleucine dioxygenase (IDO), which was found to be the enzyme responsible for the generation of (2S,3R,4S)-4-hydroxyisoleucine in Bacillus thuringiensis 2e2. Depending on the amino acid used as the substrate, IDO catalyzed three different types of oxidation reactions: hydroxylation, dehydrogenation, and sulfoxidation. IDO stereoselectively hydroxylated several hydrophobic aliphatic l-amino acids, as well as l-isoleucine, and produced (S)-3-hydroxy-l-allo-isoleucine, 4-hydroxy-l-leucine, (S)-4-hydroxy-l-norvaline, 4-hydroxy-l-norleucine, and 5-hydroxy-l-norleucine. The IDO reaction product of l-isoleucine, (2S,3R,4S)-4-hydroxyisoleucine, was again reacted with IDO and dehydrogenated into (2S,3R)-2-amino-3-methyl-4-ketopentanoate, which is also a metabolite found in B. thuringiensis 2e2. Interestingly, IDO catalyzed the sulfoxidation of some sulfur-containing l-amino acids and generated l-methionine sulfoxide and l-ethionine sulfoxide. Consequently, the effective production of various modified amino acids would be possible using IDO as the biocatalyst. PMID:21821743

  5. Investigation of Unexpected Reaction Intermediates in the Alkaline Hydrolysis of Methyl 3,5-Dinitrobenzoate

    ERIC Educational Resources Information Center

    Silva, Clesia C.; Silva, Ricardo O.; Navarro, Daniela M. A. F.; Navarro, Marcelo

    2009-01-01

    An experimental project aimed at identifying stable reaction intermediates is described. Initially, the studied reaction appears to involve the simple hydrolysis, by aqueous sodium hydroxide, of methyl 3,5-dinitrobenzoate dissolved in dimethyl sulfoxide. On mixing the substrates, however, the reaction mixture unexpectedly turns an intense red in…

  6. Radiological Studies Reveal Radial Differences in the Architecture of the Polysaccharide Capsule of Cryptococcus neoformans

    PubMed Central

    Bryan, R. A.; Zaragoza, O.; Zhang, T.; Ortiz, G.; Casadevall, A.; Dadachova, E.

    2005-01-01

    The polysaccharide capsule of the pathogenic fungus Cryptococcus neoformans is an important virulence factor, but relatively little is known about its architecture. We applied a combination of radiological, chemical, and serological methods to investigate the structure of this polysaccharide capsule. Exposure of C. neoformans cells to gamma radiation, dimethyl sulfoxide, or radiolabeled monoclonal antibody removed a significant part of the capsule. Short intervals of gamma irradiation removed the outer portion of the cryptococcal capsule without killing cells, which could subsequently repair their capsules. Survival analysis of irradiated wild-type, acapsular mutant, and complemented mutant strains demonstrated that the capsule contributed to radioprotection and had a linear attenuation coefficient higher than that of lead. The capsule portions remaining after dimethyl sulfoxide or gamma radiation treatment were comparable in size, 65 to 66 μm3, and retained immunoreactivity for a monoclonal antibody to glucuronoxylomannan. Simultaneous or sequential treatment of the cells with dimethyl sulfoxide and radiation removed the remaining capsule so that it was not visible by light microscopy. The capsule could be protected against radiation by either of the free radical scavengers ascorbic acid and sorbitol. Sugar composition analysis of polysaccharide removed from the outer and inner parts of the capsule revealed significant differences in glucuronic acid and xylose molar ratios, implying differences in the chemical structure of the constituent polysaccharides. Our results provide compelling evidence for the existence of two zones in the C. neoformans capsule that differ in susceptibility to dimethyl sulfoxide and radiation and, possibly, in packing and composition. PMID:15701808

  7. Structural properties of schiff bases of 4-aminophenol in DMSO solutions on the data density, viscosity and ultrasound speed at 308.15 K

    NASA Astrophysics Data System (ADS)

    Baluja, Shipra; Vaishnani, K. P.

    2013-08-01

    Density, ultrasonic velocity and viscosity of some Schiff bases of 4-aminophenol have been measured in dimethyl sulfoxide solutions over a wide range of concentration at 308.15 K. From these experimental data, some acoustical parameters have been evaluated, which helps in understanding the molecular interactions occurring in these solutions.

  8. Method for the addition of vulcanized waste rubber to virgin rubber products

    DOEpatents

    Romine, R.A.; Snowden-Swan, L.J.

    1997-01-28

    The invention is a method of using enzymes from thiophyllic microbes for selectively breaking the sulfur rubber cross-link bonds in vulcanized rubber. The process is halted at the sulfoxide or sulfone step so that a devulcanized layer is reactive with virgin rubber. 8 figs.

  9. Relationship between sensory and chemical attributes of Vidalia onions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Flavor in fresh onions is dominated by sulfur containing volatiles that are released once tissues are disrupted and the S-alk(en)yl-L-cysteine sulfoxide (ACSOs) are hydrolyzed by the enzyme alliinase. Four intensities of flavor levels of Vidalia onions were induced by cultivating sweet (Num 1006) an...

  10. Method for the addition of vulcanized waste rubber to virgin rubber products

    DOEpatents

    Romine, Robert A.; Snowden-Swan, Lesley J.

    1997-01-01

    The invention is a method of using enzymes from thiophyllic microbes for selectively breaking the sulfur rubber cross-link bonds in vulcanized rubber. The process is halted at the sulfoxide or sulfone step so that a devulcanized layer is reactive with virgin rubber.

  11. Cryopreservation of veliger larvae of trumpet shell, Charonia sauliae: an essential preparation to artificial propagation

    NASA Astrophysics Data System (ADS)

    Kang, Kyoung Ho; Zhang, Zhifeng; Bao, Zhenmin; Shao, Mingyu

    2009-09-01

    Trumpet shell, Charonia sauliae, is an endangered and valuable species, but its artificial propagation protocol has not been successfully established. To estimate the possibility of cryopreservation for larvae of C. sauliae, which is a potential preparation for its artificial reproduction and further research, in this study a protocol for the cryopreservation of veliger larvae of trumpet shell was optimized. Through a two-step cryopreservation procedure, four kinds of cryoprotectants (ethylene glycol, 1, 2-propanediol, dimethyl sulfoxide and glycerol) were employed at three concentrations (1.0, 1.5 and 2.0 molL-1) respectively and survival rates of larvae were determined after a storage of 1h. The larvae frozen with these four cryoprotectants after 1 h storage were cultured, and then survival rates were determined at 24, 72 and 120 h after thawing. Dimethyl sulfoxide at a concentration of 1.5 molL-1 showed the best protective effect in all experiments ( p<0.05). And survival rates of larvae frozen with dimethyl sulfoxide were determined after 1, 7 and 15 d of storage. The survival rates of larvae frozen with 1.5 molL-1 dimethyl sulfoxide after 1 h, 1 d, 7 d and 15 d of storage were 80.77% ±7.51%, 80.34% ±11.28%, 83.10% ±9.14% and 77.23% ±6.22% respectively. No significant differences in survival rates of larvae frozen with dimethyl sulfoxide were observed after various storage periods ( p>0.05).

  12. Rapid Methods for High-Throughput Detection of Sulfoxides▿

    PubMed Central

    Shainsky, Janna; Derry, Netta-Lee; Leichtmann-Bardoogo, Yael; Wood, Thomas K.; Fishman, Ayelet

    2009-01-01

    Enantiopure sulfoxides are prevalent in drugs and are useful chiral auxiliaries in organic synthesis. The biocatalytic enantioselective oxidation of prochiral sulfides is a direct and economical approach for the synthesis of optically pure sulfoxides. The selection of suitable biocatalysts requires rapid and reliable high-throughput screening methods. Here we present four different methods for detecting sulfoxides produced via whole-cell biocatalysis, three of which were exploited for high-throughput screening. Fluorescence detection based on the acid activation of omeprazole was utilized for high-throughput screening of mutant libraries of toluene monooxygenases, but no active variants have been discovered yet. The second method is based on the reduction of sulfoxides to sulfides, with the coupled release and measurement of iodine. The availability of solvent-resistant microtiter plates enabled us to modify the method to a high-throughput format. The third method, selective inhibition of horse liver alcohol dehydrogenase, was used to rapidly screen highly active and/or enantioselective variants at position V106 of toluene ortho-monooxygenase in a saturation mutagenesis library, using methyl-p-tolyl sulfide as the substrate. A success rate of 89% (i.e., 11% false positives) was obtained, and two new mutants were selected. The fourth method is based on the colorimetric detection of adrenochrome, a back-titration procedure which measures the concentration of the periodate-sensitive sulfide. Due to low sensitivity during whole-cell screening, this method was found to be useful only for determining the presence or absence of sulfoxide in the reaction. The methods described in the present work are simple and inexpensive and do not require special equipment. PMID:19465532

  13. Repairing oxidized proteins in the bacterial envelope using respiratory chain electrons.

    PubMed

    Gennaris, Alexandra; Ezraty, Benjamin; Henry, Camille; Agrebi, Rym; Vergnes, Alexandra; Oheix, Emmanuel; Bos, Julia; Leverrier, Pauline; Espinosa, Leon; Szewczyk, Joanna; Vertommen, Didier; Iranzo, Olga; Collet, Jean-François; Barras, Frédéric

    2015-12-17

    The reactive species of oxygen and chlorine damage cellular components, potentially leading to cell death. In proteins, the sulfur-containing amino acid methionine is converted to methionine sulfoxide, which can cause a loss of biological activity. To rescue proteins with methionine sulfoxide residues, living cells express methionine sulfoxide reductases (Msrs) in most subcellular compartments, including the cytosol, mitochondria and chloroplasts. Here we report the identification of an enzymatic system, MsrPQ, repairing proteins containing methionine sulfoxide in the bacterial cell envelope, a compartment particularly exposed to the reactive species of oxygen and chlorine generated by the host defence mechanisms. MsrP, a molybdo-enzyme, and MsrQ, a haem-binding membrane protein, are widely conserved throughout Gram-negative bacteria, including major human pathogens. MsrPQ synthesis is induced by hypochlorous acid, a powerful antimicrobial released by neutrophils. Consistently, MsrPQ is essential for the maintenance of envelope integrity under bleach stress, rescuing a wide series of structurally unrelated periplasmic proteins from methionine oxidation, including the primary periplasmic chaperone SurA. For this activity, MsrPQ uses electrons from the respiratory chain, which represents a novel mechanism to import reducing equivalents into the bacterial cell envelope. A remarkable feature of MsrPQ is its capacity to reduce both rectus (R-) and sinister (S-) diastereoisomers of methionine sulfoxide, making this oxidoreductase complex functionally different from previously identified Msrs. The discovery that a large class of bacteria contain a single, non-stereospecific enzymatic complex fully protecting methionine residues from oxidation should prompt a search for similar systems in eukaryotic subcellular oxidizing compartments, including the endoplasmic reticulum. PMID:26641313

  14. Environmental fate and effect assessment of thioridazine and its transformation products formed by photodegradation.

    PubMed

    Wilde, Marcelo L; Menz, Jakob; Trautwein, Christoph; Leder, Christoph; Kümmerer, Klaus

    2016-06-01

    An experimental and in silico quantitative structure-activity relationship (QSAR) approach was applied to assess the environmental fate and effects of the antipsychotic drug Thioridazine (THI). The sunlight-driven attenuation of THI was simulated using a Xenon arc lamp. The photodegradation reached the complete primary elimination, whereas 97% of primary elimination and 11% of mineralization was achieved after 256 min of irradiation for the initial concentrations of 500 μg L(-1) and 50 mg L(-1), respectively. A non-target approach for the identification and monitoring of transformation products (TPs) was adopted. The structure of the TPs was further elucidated using liquid chromatography-high resolution mass spectrometry (LC-HRMS). The proposed photodegradation pathway included sulfoxidation, hydroxylation, dehydroxylation, and S- and N-dealkylation, taking into account direct and indirect photolysis through a self-sensitizing process in the higher concentration studied. The biodegradability of THI and photolytic samples of THI was tested according to OECD 301D and 301F, showing that THI and the mixture of TPs were not readily biodegradable. Furthermore, THI was shown to be highly toxic to environmental bacteria using a modified luminescent bacteria test with Vibrio fischeri. This bacteriotoxic activity of THI was significantly reduced by phototransformation and individual concentration-response analysis confirmed a lowered bacterial toxicity for the sulfoxidation products Thioridazine-2-sulfoxide and Thioridazine-5-sulfoxide. Additionally, the applied QSAR models predicted statistical and rule-based positive alerts of mutagenic activities for carbazole derivative TPs (TP 355 and TP 339) formed through sulfoxide elimination, which would require further confirmatory in vitro validation tests. PMID:27020046

  15. Kinetically controlled synthesis of Au102(SPh)44 nanoclusters and catalytic application

    NASA Astrophysics Data System (ADS)

    Chen, Yongdong; Wang, Jin; Liu, Chao; Li, Zhimin; Li, Gao

    2016-05-01

    We here explore a kinetically controlled synthetic protocol for preparing solvent-solvable Au102(SPh)44 nanoclusters which are isolated from polydispersed gold nanoclusters by solvent extraction and size exclusion chromatography (SEC). The as-obtained Au102(SPh)44 nanoclusters are determined by matrix-assisted laser desorption ionization (MALDI) and electrospray ionization (ESI) mass spectrometry, in conjunction with UV-vis spectroscopy and thermogravimetric analysis (TGA). However, Au99(SPh)42, instead of Au102(SPh)44, is yielded when the polydispersed gold nanoclusters are etched in the presence of excess thiophenol under thermal conditions (e.g., 80 °C). Interestingly, the Au102(SPh)44 nanoclusters also can convert to Au99(SPh)42 with equivalent thiophenol ligands, evidenced by the analyses of UV-vis and MALDI mass spectrometry. Finally, the TiO2-supported Au102(SPh)44 nanocluster catalyst is investigated in the selective oxidation of sulfides into sulfoxides by the PhIO oxidant and gives rise to high catalytic activity (e.g., 80-99% conversion of R-S-R' sulfides with 96-99% selectivity for R-S(&z.dbd;O)-R' sulfoxides). The Au102(SPh)44/TiO2 catalyst also shows excellent recyclability in the sulfoxidation process.We here explore a kinetically controlled synthetic protocol for preparing solvent-solvable Au102(SPh)44 nanoclusters which are isolated from polydispersed gold nanoclusters by solvent extraction and size exclusion chromatography (SEC). The as-obtained Au102(SPh)44 nanoclusters are determined by matrix-assisted laser desorption ionization (MALDI) and electrospray ionization (ESI) mass spectrometry, in conjunction with UV-vis spectroscopy and thermogravimetric analysis (TGA). However, Au99(SPh)42, instead of Au102(SPh)44, is yielded when the polydispersed gold nanoclusters are etched in the presence of excess thiophenol under thermal conditions (e.g., 80 °C). Interestingly, the Au102(SPh)44 nanoclusters also can convert to Au99(SPh)42 with equivalent

  16. Titanium Salan/Salalen Complexes: The Twofaced Janus of Asymmetric Oxidation Catalysis.

    PubMed

    Talsi, Evgenii P; Bryliakova, Anna A; Bryliakov, Konstantin P

    2016-04-01

    Optically pure chiral epoxides and sulfoxides are ubiquitous building blocks in fine organic synthesis, employed in the pharmaceutical, agrochemical, and cosmetic industries. On the road to chiral epoxides and sulfoxides, efficient and stereoselective transition metal-based catalysts are the most promising guides. Among transition metals, we favor titanium for its cheapness and availability, nontoxicity, and well-known ability to catalyze a variety of stereoselective transformations, including oxidations with environmentally benign H2 O2 . In this personal account, we summarize the state-of-the-art of rational design of chiral titanium(IV) salan and salalen catalysts, and investigations of their catalytic reactivities and stereoselectivities in the epoxidations of olefins and oxidations of thioethers, unraveling the peculiarities and mechanisms of their catalytic action. PMID:26991421

  17. Effects of trichostatins on differentiation of murine erythroleukemia cells

    SciTech Connect

    Yoshida, M.; Nomura, S.; Beppu, T.

    1987-07-15

    The fungistatic antibiotics trichostatins (TS) A and C were isolated from culture broth of Streptomyces platensis No. 145 and were found to be potent inducers of differentiation in murine erythroleukemia (Friend and RV133) cells at concentrations of 1.5 X 10(-8) M for TSA and 5 X 10(-7) M for TSC. Differentiation induced by TS was cooperatively enhanced by UV irradiation but not by treatment with dimethyl sulfoxide. This enhanced activity was completely inhibited by adding cycloheximide to the culture medium 2 h after exposure to TS, suggesting that TS are dimethyl sulfoxide-type inducers of erythroid differentiation. No inhibitory effect of TS was observed on macromolecular synthesis in cultured cells.

  18. Identification of oxidized methionine residues in peptides containing two methionine residues by derivatization and matrix-assisted laser desorption/ionization mass spectrometry.

    PubMed

    Hollemeyer, Klaus; Heinzle, Elmar; Tholey, Andreas

    2002-11-01

    Oxidation of methionine residues in peptides and proteins occurs in vivo or may be an artifact resulting from purification steps. We present a three step method for the localization of methionine sulfoxides in peptides with two methionine residues. In the first step, the N-terminus as well as other reactive side chain functions are blocked by acetylation. The resulting protected peptides are cleaved by cyanogen bromide. The cleavage does not occur at methionine sulfoxide but only at reduced methionine residues forming new amino termini. The newly formed amino group is then derivatized with a bromine containing compound in the last step of the procedure. The resulting peptide can easily be identified by matrix-assisted laser desorption/ionization-time of flight mass spectrometry using both the characteristic isotope pattern of the halogen and the metastable loss of methanesulfenic acid from oxidized residues. This procedure allows the unequivocal localization of oxidized methionines even in complex peptide mixtures. PMID:12442252

  19. Hydrolysis of plutonium: Corrosion kinetics in DMSO solutions containing simulated high explosive and water

    SciTech Connect

    Haschke, J.M.; Pruner, R.E. II

    1995-01-01

    A sequence of experiments is described that address the compatibility of plutonium metal with dimethyl sulfoxide solvent and with solutions containing simulated HMX explosive and simulated explosive plus water. In the absence of water, reaction is slow and forms a thin adherent product layer on clean metal surfaces. Corrosion of oxide-coated plutonium is observed after 15 to 20 days in a solution containing 0.18 mass % (0.11 M) water. After corrosion initiates, the rate accelerates rapidly and attains a value of 0.13 mg Pu/cm{sup 2} h with a surface that is approximately one percent active. Dependence of the Pu + H{sub 2}O reaction on water concentration is evaluated using the data from literature sources. Hazards associated with the use of wet dimethyl sulfoxide as a solvent for removing explosives during weapon dismantlement are identified and a simple method for their mitigation is outlined.

  20. Polar/apolar compounds induce leukemia cell differentiation by modulating cell-surface potential.

    PubMed Central

    Arcangeli, A; Carlà, M; Del Bene, M R; Becchetti, A; Wanke, E; Olivotto, M

    1993-01-01

    The mechanism of action of polar/apolar inducers of cell differentiation, such as dimethyl sulfoxide and hexamethylene-bisacetamide, is still obscure. In this paper evidence is provided that their effects on murine erythroleukemia cells are modulated by various extracellular cations as a precise function of the cation effects on membrane surface potential. The interfacial effects of the inducers were directly measured on the charged electrode, showing that both dimethyl sulfoxide and hexamethylene-bisacetamide, at the effective concentrations for cell differentiation and within the physiological range of charge density, adsorb at the charged surface and produce a potential shift. A linear correlation was found between this shift and the inducer effects on cell differentiation. Besides offering a different interpretation of the mechanism of action of the inducers, these findings indicate that surface potential has a signaling function. They may also be relevant to cancer treatments based on tumor-cell commitment to terminal differentiation. Images Fig. 1 PMID:8516337

  1. Hypochlorous acid reacts with the N-terminal methionines of proteins to give dehydromethionine, a potential biomarker for neutrophil-induced oxidative stress.

    PubMed

    Beal, Jennifer L; Foster, Steven B; Ashby, Michael T

    2009-11-24

    Electrophilic halogenating agents, including hypohalous acids and haloamines, oxidize free methionine and the N-terminal methionines of peptides and proteins (e.g., Met-1 of anti-inflammatory peptide 1 and ubiquitin) to produce dehydromethionine (a five-membered isothiazolidinium heterocycle). Amide derivatives of methionine are oxidized to the corresponding sulfoxide derivatives under the same reaction conditions (e.g., Met-3 of anti-inflammatory peptide 1). Other biological oxidants, including hydrogen peroxide and peroxynitrite, also produce only the corresponding sulfoxides. Hypothiocyanite does not react with methionine residues. We suggest that dehydromethionine may be a useful biomarker for the myeloperoxidase-induced oxidative stress associated with many inflammatory diseases. PMID:19839600

  2. Electrodeposition and Characterization of Bismuth Telluride Nanowires

    NASA Astrophysics Data System (ADS)

    Frantz, C.; Stein, N.; Gravier, L.; Granville, S.; Boulanger, C.

    2010-09-01

    In this work, we report thermoelectric measurements on electroplated bismuth telluride nanowires. Porous polycarbonate membranes, obtained by ion-track irradiation lithography, were chosen as electroplating templates. Bismuth telluride nanowires were achieved in acidic media under potentiostatic conditions at -100 mV versus saturated silver chloride electrode. The filling ratio of the pores was increased to 80% by adding dimethyl sulfoxide to the electrolyte. Whatever the experimental conditions, the nanowires were polycrystalline in the rhombohedral phase of Bi2Te3. Finally, the power output of arrays of bismuth telluride nanowires was analyzed as a function of load resistance. The results were strongly dependent on the internal resistance, which can be significantly reduced by the presence of dimethyl sulfoxide during electroplating.

  3. Post-translational oxidative modification of fibrinogen is associated with coagulopathy after traumatic injury.

    PubMed

    White, Nathan J; Wang, Yi; Fu, Xiaoyun; Cardenas, Jessica C; Martin, Erika J; Brophy, Donald F; Wade, Charles E; Wang, Xu; St John, Alexander E; Lim, Esther B; Stern, Susan A; Ward, Kevin R; López, José A; Chung, Dominic

    2016-07-01

    Victims of trauma often develop impaired blood clot formation (coagulopathy) that contributes to bleeding and mortality. Fibrin polymerization is one critical component of clot formation that can be impacted by post-translational oxidative modifications of fibrinogen after exposure to oxidants. In vitro evidence suggests that Aα-C domain methionine sulfoxide formation, in particular, can induce conformational changes that prevent lateral aggregation of fibrin protofibrils during polymerization. We used mass spectrometry of plasma from trauma patients to find that fibrinogen Aα-C domain methionine sulfoxide content was selectively-increased in patients with coagulopathy vs. those without coagulopathy. This evidence supports a novel linkage between oxidative stress, coagulopathy, and bleeding after injury. PMID:27105953

  4. A novel iron complex containing an N,O-type bidentate oxazoline ligand: Synthesis, X-ray studies, DFT calculations and catalytic activity

    NASA Astrophysics Data System (ADS)

    Amini, Mojtaba; Arab, Ali; Derakhshandeh, Parviz Gohari; Bagherzadeh, Mojtaba; Ellern, Arkady; Woo, L. Keith

    2014-12-01

    A five-coordinated Fe(III) complex with the distorted trigonal bipyramidal configuration was synthesized by reactions of FeCl3ṡ6H2O and 2-(2";-hydroxyphenyl)oxazoline (Hphox) as a bidentate Osbnd N donor oxazoline ligand. Complex [Fe(phox)2Cl] was fully characterized, including by single-crystal X-ray structure analysis. DFT calculations were accompanied with experimental results in order to obtain a deeper insight into the electronic structure and vibrational normal modes of complex. Oxidation of sulfides to sulfoxides in one-step was conducted by this complex as catalyst using urea hydrogen peroxide (UHP) in mixture of CH2Cl2/CH3OH (1:1) under air at room temperature. The results show that using this system in oxidation of sulfides, sulfoxides are obtained as the main products, together with variable amounts of sulfones (⩽13%), depending on the nature of the substrate.

  5. Transduction of pressure signal to electrical signal upon sudden increase in turgor pressure in Chara corallina.

    PubMed

    Shimmen, Teruo; Ogata, Koreaki

    2013-05-01

    By taking advantage of large cell size of Chara corallina, we analyzed the membrane depolarization induced by decreased turgor pressure (Shimmen in J Plant Res 124:639-644, 2011). In the present study, the response to increased turgor pressure was analyzed. When internodes were incubated in media containing 200 mM dimethyl sulfoxide, their intracellular osmolality gradually increased and reached a steady level after about 3 h. Upon removal of dimethyl sulfoxide, turgor pressure quickly increased. In response to the increase in turgor pressure, the internodes generated a transient membrane depolarization at its nodal end. The refractory period was very long and it took about 2 h for full recovery after the depolarizing response. Involvement of protein synthesis in recovery from refractoriness was suggested, based on experiments using inhibitors. PMID:23154838

  6. Thioredoxin-dependent Redox Regulation of Cellular Signaling and Stress Response through Reversible Oxidation of Methionines

    SciTech Connect

    Bigelow, Diana J.; Squier, Thomas C.

    2011-06-01

    Generation of reactive oxygen species (ROS) is a common feature of many forms of stress to which plants are exposed. Successful adaptation to changing environmental conditions requires sensitive sensors of ROS such as protein-bound methionines that are converted to their corresponding methionine sulfoxides, which in turn can influence cellular signaling pathways. Such a signaling protein is calmodulin, which represents an early and central point in calcium signaling pathways important to stress response in plants. We describe recent work elucidating fundamental mechanisms of reversible methionine oxidation within calmodulin, including the sensitivity of individual methionines within plant and animal calmodulin to ROS, the structural and functional consequences of their oxidation, and the interactions of oxidized calmodulin with methionine sulfoxide reductase enzymes.

  7. 5-(Naphthalen-1-yl)isophthalic acid–dimethyl sulfoxide–water (2/1/2)

    PubMed Central

    Vetter, Antje; Seichter, Wilhelm; Weber, Edwin

    2013-01-01

    The asymmetric unit of the title compound, 2C18H12O4·C2H6OS·2H2O, consists of four crystallographically independent mol­ecules of 5-(naphthalen-1-yl)isophthalic acid, two dimethyl sulfoxide and four water mol­ecules. The dihedral angles formed by the the planes of the aromatic fragments of the organic mol­ecules range from 57.4 (1) to 59.1 (1)°. In the crystal, multiple O—H⋯O hydrogen bonds link the water mol­ecules with the carbonyl and sulfoxide groups, giving rise to double ribbons along the b-axis direction. PMID:23795084

  8. A comparison of two different methods for formation of the beta phase in nanocomposites based on vinylidene fluoride-hexafluoropropylene copolymer

    NASA Astrophysics Data System (ADS)

    Borisova, Lyudmila; Kiryakova, Dimitrina; Atanassov, Atanas

    2014-06-01

    Nanocomposite materials based on vinylidene fluoride-hexafluoropropylene copolymer and organically modified montmorillonite Cloisite®15A were prepared by two different methods: melt mixing and co-precipitation. The changes taking place in crystalline structure, tensile strength, thermal behavior and the formation of piezoelectric b-phase as a result of the polymer system dissolution in dimethyl sulfoxide were studied. The technological specificity of each method has certain effect on the properties of the obtained nanocomposites. The highest content of b-phase — 95 % was achieved by co-precipitation from the solution of vinylidene fluoride-hexafluoropropylene copolymer in dimethyl sulfoxide and 6 mass % content of Cloisite®15A. Despite the common view that the use of solvents and prolonged technological procedure lead to overall higher expenses, the obtained nanocomposites could be promising for the preparation of new piezo-materials.

  9. NMR investigation of methyl-2,4-dimethoxysalicylate: Effect of solvent and temperature

    NASA Astrophysics Data System (ADS)

    Dabbagh, Hossein A.; Najafi, Alireza C.; Noroozi-Pesyan, Nader

    2006-07-01

    1H NMR and 13C NMR of methyl-2,4-dimethoxysalicylate 2 was measured in chloroform-d at the temperature range of 220-330 K, in dimethyl sulfoxide-d 6 at the temperature range of 300-400 K and in a polar protic solvent (CD 3OD) at 300 K. The structure of 2 in liquid phase (solvent) is compared with those in solid phase (X-ray) and in the gas phase (quantum mechanical calculations). The relationship between molecular geometry, 1H NMR chemical shift and W coupling of involved protons has a complex nature, but hydrogen bonds [C dbnd O⋯H-O and C dbnd O⋯H-CH 2O] strength is the principle factor.

  10. Formation and anti-tumor activity of uncommon in vitro and in vivo metabolites of CPI-613, a novel anti-tumor compound that selectively alters tumor energy metabolism.

    PubMed

    Lee, King C; Shorr, Robert; Rodriguez, Robert; Maturo, Claudia; Boteju, Lakmal W; Sheldon, Adrian

    2011-08-01

    CPI-613 is a novel anti-tumor compound with a mechanism-of-action which appears distinct from the current classes of anti-cancer agents used in the clinic. CPI-613 demonstrates both in vitro and in vivo anti-tumor activity. In vitro metabolic studies using liver S9 were performed which demonstrated that CPI-613 undergoes both phase 1 (oxidation) and phase 2 (glucuronidation) transformations. Its metabolic half-life varied between species and ranged from 8 minutes (Hanford minipig) to 47 minutes (CD-1 mouse). We performed metabolite mass assessments using selected in vitro incubation samples and demonstrated that +16 amu oxidation with and without +176 amu glucuronidation products were generated by human and animal liver S9. LC/MS/MS fragmentation patterns showed that an uncommon sulfoxide metabolite was formed and the O-glucuronidation occurred at the terminal carboxyl moiety. We observed that the +192 amu sulfoxide/glucuronide was generated only in human liver S9 and not by any of the other species tested. Synthetic metabolites were prepared and compared with the enzymatically-generated metabolites. Both the chromatographic retention times and the LC/MS/MS fragmentation patterns were similar, demonstrating that the synthetic metabolites were virtually identical to the S9-generated products. CYP450 reaction phenotyping and inhibition data both suggested that multiple CYP isozymes (2C8 and 3A4, along with minor contributions by 2C9 and 2C19) were involved in CPI-613 metabolism and sulfoxide formation. Plasma samples from human subjects dosed with CPI-613 also contained the sulfoxide ± glucuronide metabolites. These results show that the in vitro- and in vivo-generated phase 1 and phase 2 metabolites were in good agreement. PMID:21722089

  11. NMR study of thymulin, a lymphocyte differentiating thymic nonapeptide. Conformational states of free peptide in solution.

    PubMed

    Laussac, J P; Cung, M T; Pasdeloup, M; Haran, R; Marraud, M; Lefrancier, P; Dardenne, M; Bach, J F

    1986-06-15

    The nonapeptide less than Glu-Ala-Lys-Ser-Gln-Gly-Gly-Ser-Asn (formerly called serum thymic factor) is a factor produced by the thymic epithelium, which needs a zinc ion to express its immunoregulatory properties. We report here on 1H and 13C NMR investigation of the conformational properties of the free peptide in aqueous medium and in dimethyl sulfoxide-d6 solution by a combination of homo- and heteronuclear one- and two-dimensional experiments. The various resonances have been assigned in a straightforward manner on the basis of 1H,1H COSY spectroscopy for the recognition of the proton spin systems; two-dimensional NOESY spectra with the correlation peaks across amide bonds and for the amino acid sequence assignment; amide bonds and for the amino acid sequence assignment; 13C,1H COSY experiments using selective polarization transfer from 1H- to 13C-nucleus via the 13C,1H long-range couplings for the attribution of the carboxyl and carbonyl groups; and 13C,1H COSY experiments with selective polarization transfer via the 13C,1H direct couplings for the assignment of all the aliphatic carbons. Other experiments such as pH-dependent chemical shifts, combined use of multiple and selective proton-decoupled 1H and 13C NMR spectra, the temperature and the concentration dependence of the proton shifts of the amide resonances, the solvent dependences of peptide carbonyl carbon resonances, and comparison of the spectra with three different analogues were performed. In aqueous solution, the data are compatible with the assumption of a highly mobile dynamic equilibrium among different conformations, whereas in dimethyl sulfoxide-d6, a more rigid structure is found involving three internal hydrogen bonds. These observations provide an insight into the conformational tendencies of this peptidic hormone in two different media. PMID:3711109

  12. Electronic and vibrational circular dichroism spectra of (R)-(-)-apomorphine

    NASA Astrophysics Data System (ADS)

    Abbate, Sergio; Longhi, Giovanna; Lebon, France; Tommasini, Matteo

    2012-09-01

    Apomorphine is a chiral drug molecule; notwithstanding its extraordinary importance, little attention has been paid to the characterization of its chiroptical properties. Here we report on its electronic circular dichroism (ECD) spectra, recorded in methanol and water, and vibrational circular dichroism (VCD) in methanol and dimethyl sulfoxide (DMSO) solutions. Density functional theory (DFT) calculations have allowed us to interpret the spectra and to evaluate the role of possible conformations, charge-states and interactions with counter ions.

  13. Radical-mediated dehydrative preparation of cyclic imides using (NH4)2S2O8–DMSO: application to the synthesis of vernakalant

    PubMed Central

    Garad, Dnyaneshwar N; Tanpure, Subhash D

    2015-01-01

    Summary Ammonium persulfate–dimethyl sulfoxide (APS–DMSO) has been developed as an efficient and new dehydrating reagent for a convenient one-pot process for the synthesis of miscellaneous cyclic imides in high yields starting from readily available primary amines and cyclic anhydrides. A plausible radical mechanism involving DMSO has been proposed. The application of this facile one-pot imide forming process has been demonstrated for a practical synthesis of vernakalant. PMID:26199655

  14. Aromatic fluorine compounds. VII. Replacement of aromatic -Cl and -NO2 groups by -F

    USGS Publications Warehouse

    Finger, G.C.; Kruse, C.W.

    1956-01-01

    Replacement of -Cl by -F in aryl chlorides with potassium fluoride has been extended from 2,4-dinitrochlorobenzene to less activated halides by the use of non-aqueous solvents, especially dimethylformamide (DMF) and dimethyl sulfoxide (DMSO). Also replacement of -NO2 by -F in substituted nitrobenzenes was studied in DMF. As a direct result of this study, many aromatic fluorine compounds can now be obtained by a relatively simple synthetic route.

  15. Radical-mediated dehydrative preparation of cyclic imides using (NH4)2S2O8-DMSO: application to the synthesis of vernakalant.

    PubMed

    Garad, Dnyaneshwar N; Tanpure, Subhash D; Mhaske, Santosh B

    2015-01-01

    Ammonium persulfate-dimethyl sulfoxide (APS-DMSO) has been developed as an efficient and new dehydrating reagent for a convenient one-pot process for the synthesis of miscellaneous cyclic imides in high yields starting from readily available primary amines and cyclic anhydrides. A plausible radical mechanism involving DMSO has been proposed. The application of this facile one-pot imide forming process has been demonstrated for a practical synthesis of vernakalant. PMID:26199655

  16. Purifying contaminated water

    DOEpatents

    Daughton, Christian G.

    1983-01-01

    Process for removing biorefractory compounds from contaminated water (e.g., oil shale retort waste-water) by contacting same with fragmented raw oil shale. Biorefractory removal is enhanced by preactivating the oil shale with at least one member of the group of carboxylic, acids, alcohols, aldehydes, ketones, ethers, amines, amides, sulfoxides, mixed ether-esters and nitriles. Further purification is obtained by stripping, followed by biodegradation and removal of the cells.

  17. Pentacoordination of the silicon atom in (2-organylsulfinylethyl)trifluorosilanes

    SciTech Connect

    Voronkov, M.G.; Klyba, L.V.; Aksamentova, T.N.; Gavrilova, G.A.; Sorokin, M.S.; Vitkovskii, V.Yu.; Modonov, V.B.; Chipanina, N.N.; Frolov, Yu.L.

    1986-12-10

    The authors study the formation of the intramolcular coordination bond of silicon with the oxygen atom of a sulfoxide group (SG) in the case of (2-organylsulfinylethyl)trifluorosilanes RS(O)CH/sub 2/CH/sub 2/SiF/sub 3/, where R = Me (I), Et (II), and PhCH/sub 2/ (III) using IR and UV spectroscopy, dipole moment data, and mass spectrometry.

  18. Sulfur species behavior in soil organic matter during decomposition

    NASA Astrophysics Data System (ADS)

    Schroth, Andrew W.; Bostick, Benjamin C.; Graham, Margaret; Kaste, James M.; Mitchell, Myron J.; Friedland, Andrew J.

    2007-12-01

    Soil organic matter (SOM) is a primary reservoir of terrestrial sulfur (S), but its role in the global S cycle remains poorly understood. We examine S speciation by X-ray absorption near-edge structure (XANES) spectroscopy to describe S species behavior during SOM decomposition. Sulfur species in SOM were best represented by organic sulfide, sulfoxide, sulfonate, and sulfate. The highest fraction of S in litter was organic sulfide, but as decomposition progressed, relative fractions of sulfonate and sulfate generally increased. Over 6-month laboratory incubations, organic sulfide was most reactive, suggesting that a fraction of this species was associated with a highly labile pool of SOM. During humification, relative concentrations of sulfoxide consistently decreased, demonstrating the importance of sulfoxide as a reactive S phase in soil. Sulfonate fractional abundance increased during humification irrespective of litter type, illustrating its relative stability in soils. The proportion of S species did not differ systematically by litter type, but organic sulfide became less abundant in conifer SOM during decomposition, while sulfate fractional abundance increased. Conversely, deciduous SOM exhibited lesser or nonexistent shifts in organic sulfide and sulfate fractions during decomposition, possibly suggesting that S reactivity in deciduous litter is coupled to rapid C mineralization and independent of S speciation. All trends were consistent in soils across study sites. We conclude that S reactivity is related to speciation in SOM, particularly in conifer forests, and S species fractions in SOM change during decomposition. Our data highlight the importance of intermediate valence species (sulfoxide and sulfonate) in the pedochemical cycling of organic bound S.

  19. METAL PHTHALOCYANINES

    DOEpatents

    Frigerio, N.A.

    1962-03-27

    A process is given for preparing heavy metal phthalocyanines, sulfonated or not. The process comprises mixing an inorganic metal salt with dimethyl formamide or methyl sulfoxide; separating the metal complex formed from the solution; mixing the complex with an equimolar amount of sodium, potassium, lithium, magnesium, or beryllium sulfonated or unsulfonated phthalocyanine whereby heavy-metal phthalocyanine crystals are formed; and separating the crystals from the solution. Uranyl, thorium, lead, hafnium, and lanthanide rare earth phthalocyanines can be produced by the process. (AEC)

  20. Electron impact and chemical ionization mass spectral analysis of a volatile uranyl derivative

    SciTech Connect

    Reutter, D.J.; Hardy, D.R.

    1981-01-01

    Quadrupole mass spectral analysis of the volatile uranium ligand complex bis (1,1,1,5,5,5-hexafluoro-2,4-pentanedionato) dioxouranium-di-n-butyl sulfoxide is described utilizing electron impact (EI) and methane chemical ionization (CI) ion sources. All major ions are tentatively identified and the potential usefulness of this complex for determining uranium isotope /sup 235/U//sup 238/U abundance is demonstrated.

  1. Pt and Pd catalyzed oxidation of Li2O2 and DMSO during Li-O2 battery charging.

    PubMed

    Gittleson, Forrest S; Ryu, Won-Hee; Schwab, Mark; Tong, Xiao; Taylor, André D

    2016-05-01

    Rechargeable Li-O2 and Li-air batteries require electrode and electrolyte materials that synergistically promote long-term cell operation. In this study, we investigate the role of noble metals Pt and Pd as catalysts in the Li-O2 oxidation process and their compatibility with dimethyl sulfoxide (DMSO) based electrolytes. We identify a basis for low potential Li2O2 evolution followed by oxidative decomposition of the electrolyte to form carbonate side products. PMID:27111589

  2. Rapid Method for Quantifying the Extent of Methionine Oxidation in Intact Calmodulin

    SciTech Connect

    Galeva, Nadezhda A.; Esch, S Wynn; Williams, Todd D.; Markillie, Lye MENG.; Squier, Thomas C.

    2005-09-01

    We have developed a method for rapidly quantifying the extent to which the functionally important Met144 and Met145 residues near the C-terminus of calmodulin (CaM) are converted to the corresponding sulfoxides, Met(O). The method utilizes a whole protein collision induced dissociation (CID) approach on an electrospray ionization quadrupole time-of-flight (ESI-Q-TOF) mass spectrometer. Using standards of CaM oxidized by hydrogen peroxide (H2O2) or peroxynitrite (ONOO-), we demonstrated that CID fragmentation of the protein ions resulted in a series of C-terminal singly charged y1?y15 ions. Fragments larger than y4 exhibited mass shifts of +16 or +32 Da, corresponding to oxidation of one or two methionines, respectively. To assess the extent of oxidative modification for Met144 and Met145 to Met(O), we averaged the ratio of intensities for yn, yn +16, and yn +32 ions, where n = 6?9. By alternating MS and CID scans at low and high collision energies, this technique allowed us to rapidly determine both the distribution of intact CaM oxiforms and the extent of oxidative modification in the C-terminal region of the protein in a single run. We have applied the method to studies of the repair of fully oxidized CaM by methionine sulfoxide reductases (MsrA and MsrB), which normally function in concert to reduce the S and R stereoisomers of methionine sulfoxide. We found that repair of Met(O)144 and Met(O)145 did not go to completion, but was more efficient than average Met repair. Absence of complete repair is consistent with previous studies showing that accumulation of methionine sulfoxide in CaM can occur during aging.

  3. Biomimetic hydrogel materials

    DOEpatents

    Bertozzi, Carolyn; Mukkamala, Ravindranath; Chen, Qing; Hu, Hopin; Baude, Dominique

    2000-01-01

    Novel biomimetic hydrogel materials and methods for their preparation. Hydrogels containing acrylamide-functionalized carbohydrate, sulfoxide, sulfide or sulfone copolymerized with a hydrophilic or hydrophobic copolymerizing material selected from the group consisting of an acrylamide, methacrylamide, acrylate, methacrylate, vinyl and a derivative thereof present in concentration from about 1 to about 99 wt %. and methods for their preparation. The method of use of the new hydrogels for fabrication of soft contact lenses and biomedical implants.

  4. Biomimetic Hydrogel Materials

    DOEpatents

    Bertozzi, Carolyn , Mukkamala, Ravindranath , Chen, Oing , Hu, Hopin , Baude, Dominique

    2003-04-22

    Novel biomimetic hydrogel materials and methods for their preparation. Hydrogels containing acrylamide-functionalized carbohydrate, sulfoxide, sulfide or sulfone copolymerized with a hydrophilic or hydrophobic copolymerizing material selected from the group consisting of an acrylamide, methacrylamide, acrylate, methacrylate, vinyl and a derivative thereof present in concentration from about 1 to about 99 wt %. and methods for their preparation. The method of use of the new hydrogels for fabrication of soft contact lenses and biomedical implants.

  5. Purifying contaminated water. [DOE patent application

    DOEpatents

    Daughton, C.G.

    1981-10-27

    Process is presented for removing biorefactory compounds from contaminated water (e.g., oil shale retort waste-water) by contacting same with fragmented raw oil shale. Biorefractory removal is enhanced by preactivating the oil shale with at least one member of the group of carboxylic acids, alcohols, aldehydes, ketones, ethers, amines, amides, sulfoxides, mixed ether-esters and nitriles. Further purification is obtained by stripping, followed by biodegradation and removal of the cells.

  6. Molecular Complexity via C–H Activation: A Dehydrogenative Diels-Alder Reaction

    PubMed Central

    Stang, Erik M.; White, M. Christina

    2011-01-01

    Traditionally, C–H oxidation reactions install oxidized functionality onto a preformed molecular skeleton, resulting in a local molecular change. The use of C–H activation chemistry to construct complex molecular scaffolds is a new area with tremendous potential in synthesis. We report a Pd(II)/bis-sulfoxide catalyzed dehydrogenative Diels-Alder reaction that converts simple terminal olefins into complex cycloadducts in a single operation. PMID:21842902

  7. Theoretical investigation of the electronic structure of a substituted nickel phthalocyanine

    NASA Astrophysics Data System (ADS)

    Kaur, Prabhjot; Sachdeva, Ritika; Singh, Sukhwinder

    2016-05-01

    The optimized geometry and electronic structure of an organic compound nickel phthalocyanine tetrasulfonic acid tetra sodium salt have been investigated using density functional theory. We have also optimized the structure of nickel phthalocyanine tetrasulfonic acid tetra sodium salt in dimethyl sulfoxide to study effects of solvent on the electronic structure and transitions. Experimentally, the electronic transitions have been studied using UV-VIS spectroscopic technique. It is observed that the electronic transitions obtained from the theoretical studies generally agree with the experiment.

  8. Sulfur species behavior in soil organic matter during decomposition

    USGS Publications Warehouse

    Schroth, A.W.; Bostick, B.C.; Graham, M.; Kaste, J.M.; Mitchell, M.J.; Friedland, A.J.

    2007-01-01

    Soil organic matter (SOM) is a primary re??servoir of terrestrial sulfur (S), but its role in the global S cycle remains poorly understood. We examine S speciation by X-ray absorption near-edge structure (XANES) spectroscopy to describe S species behavior during SOM decomposition. Sulfur species in SOM were best represented by organic sulfide, sulfoxide, sulfonate, and sulfate. The highest fraction of S in litter was organic sulfide, but as decomposition progressed, relative fractions of sulfonate and sulfate generally increased. Over 6-month laboratory incubations, organic sulfide was most reactive, suggesting that a fraction of this species was associated with a highly labile pool of SOM. During humification, relative concentrations of sulfoxide consistently decreased, demonstrating the importance of sulfoxide as a reactive S phase in soil. Sulfonate fractional abundance increased during humification irrespective of litter type, illustrating its relative stability in soils. The proportion of S species did not differ systematically by litter type, but organic sulfide became less abundant in conifer SOM during decomposition, while sulfate fractional abundance increased. Conversely, deciduous SOM exhibited lesser or nonexistent shifts in organic sulfide and sulfate fractions during decomposition, possibly suggesting that S reactivity in deciduous litter is coupled to rapid C mineralization and independent of S speciation. All trends were consistent in soils across study sites. We conclude that S reactivity is related to spqciation in SOM, particularly in conifer forests, and S species fractions in SOM change, during decomposition. Our data highlight the importance of intermediate valence species (sulfoxide and sulfonate) in the pedochemical cycling of organic bound S. Copyright 2007 by the American Geophysical Union.

  9. Pt and Pd catalyzed oxidation of Li2O2 and DMSO during Li–O2 battery charging

    DOE PAGESBeta

    Gittleson, Forrest S.; Ryu, Won-Hee; Schwab, Mark; Tong, Xiao; Taylor, André D.

    2016-01-01

    Rechargeable Li-O2 and Li-air batteries require electrode and electrolyte materials that synergistcally promote long-term cell operation. We investigate the role of noble metals Pt and Pd as catalysts for the Li-O2 oxidation process and their compatibility with a dimethyl sulfoxide (DMSO) based electrolyte. Lastly, we identify a basis for low potential Li2O2 evolution followed by oxidative decomposition of the electrolyte to form carbonate side products.

  10. Evaluation of anti-freeze viscosity modifier for potential external tank applications

    NASA Technical Reports Server (NTRS)

    Lynn, R. O. L.

    1981-01-01

    Viscosity modifiers and gelling agents were evaluated in combination with ethylene glycol and dimethyl sulfoxide water eutectics. Pectin and agarose are found to gel these eutectics effectively in low concentration, but the anti-freeze protection afforded by these compositions is found to be marginal in simulations of the intended applications. Oxygen vent shutters and vertical metallic surfaces were simulated, with water supplied as a spray, dropwise, and by condensation from the air.

  11. Aminoxidation of Arenethiols to N-Chloro-N-sulfonyl Sulfinamides.

    PubMed

    Yang, Zhanhui; Xu, Wei; Wu, Qiuyue; Xu, Jiaxi

    2016-04-01

    A simple and efficient method to synthesize N-chloro-N-sulfonylsulfinamides by the direct aminoxidation of arenethiols under aqueous and mild conditions is disclosed, geminally installing the oxo and amino groups on the sulfur atom of arenethiols. The products have been primarily developed as sulfinylation reagents to convert Grignard reagents into sulfoxides, and as amination reagents to convert secondary amines into hydrazine derivatives. PMID:26974865

  12. Identification of a flavin-containing S-oxygenating monooxygenase involved in alliin biosynthesis in garlic.

    PubMed

    Yoshimoto, Naoko; Onuma, Misato; Mizuno, Shinya; Sugino, Yuka; Nakabayashi, Ryo; Imai, Shinsuke; Tsuneyoshi, Tadamitsu; Sumi, Shin-ichiro; Saito, Kazuki

    2015-09-01

    S-Alk(en)yl-l-cysteine sulfoxides are cysteine-derived secondary metabolites highly accumulated in the genus Allium. Despite pharmaceutical importance, the enzymes that contribute to the biosynthesis of S-alk-(en)yl-l-cysteine sulfoxides in Allium plants remain largely unknown. Here, we report the identification of a flavin-containing monooxygenase, AsFMO1, in garlic (Allium sativum), which is responsible for the S-oxygenation reaction in the biosynthesis of S-allyl-l-cysteine sulfoxide (alliin). Recombinant AsFMO1 protein catalyzed the stereoselective S-oxygenation of S-allyl-l-cysteine to nearly exclusively yield (RC SS )-S-allylcysteine sulfoxide, which has identical stereochemistry to the major natural form of alliin in garlic. The S-oxygenation reaction catalyzed by AsFMO1 was dependent on the presence of nicotinamide adenine dinucleotide phosphate (NADPH) and flavin adenine dinucleotide (FAD), consistent with other known flavin-containing monooxygenases. AsFMO1 preferred S-allyl-l-cysteine to γ-glutamyl-S-allyl-l-cysteine as the S-oxygenation substrate, suggesting that in garlic, the S-oxygenation of alliin biosynthetic intermediates primarily occurs after deglutamylation. The transient expression of green fluorescent protein (GFP) fusion proteins indicated that AsFMO1 is localized in the cytosol. AsFMO1 mRNA was accumulated in storage leaves of pre-emergent nearly sprouting bulbs, and in various tissues of sprouted bulbs with green foliage leaves. Taken together, our results suggest that AsFMO1 functions as an S-allyl-l-cysteine S-oxygenase, and contributes to the production of alliin both through the conversion of stored γ-glutamyl-S-allyl-l-cysteine to alliin in storage leaves during sprouting and through the de novo biosynthesis of alliin in green foliage leaves. PMID:26345717

  13. Studies on the Low-Temp Oxidation of Coal Containing Organic Sulfur and the Corresponding Model Compounds.

    PubMed

    Zhang, Lanjun; Li, Zenghua; Li, Jinhu; Zhou, Yinbo; Yang, Yongliang; Tang, Yibo

    2015-01-01

    This paper selects two typical compounds containing organic sulfur as model compounds. Then, by analyzing the chromatograms of gaseous low-temp oxidation products and GC/MS of the extractable matter of the oxidation residue, we summarizing the mechanism of low-temp sulfur model compound oxidation. The results show that between 30°C to 80°C, the interaction between diphenyl sulfide and oxygen is mainly one of physical adsorption. After 80°C, chemical adsorption and chemical reactions begin. The main reaction mechanism in the low-temp oxidation of the model compound diphenyl sulfide is diphenyl sulfide generates diphenyl sulfoxide, and then this sulfoxide is further oxidized to diphenyl sulphone. A small amount of free radicals is generated in the process. The model compound cysteine behaves differently from diphenyl sulfide. The main reaction low-temp oxidation mechanism involves the thiol being oxidized into a disulphide and finally evolving to sulfonic acid, along with SO₂ being released at 130°C and also a small amount of free radicals. We also conducted an experiment on coal from Xingcheng using X-ray photoelectron spectroscopy (XPS). The results show that the major forms of organic sulfur in the original coal sample are thiophene and sulfone. Therefore, it can be inferred that there is none or little mercaptan and thiophenol in the original coal. After low-temp oxidation, the form of organic sulfur changes. The sulfide sulfur is oxidized to the sulfoxide, and then the sulfoxide is further oxidized to a sulfone, and these steps can be easily carried out under experimental conditions. What's more, the results illustrate that oxidation promotes sulfur element enrichment on the surface of coal. PMID:26690405

  14. Nutritional value and safety of methionine derivatives, isomeric dipeptides and hydroxy analogs in mice.

    PubMed

    Friedman, M; Gumbmann, M R

    1988-03-01

    Weight gains in mice fed amino acid diets containing methionine and 16 methionine derivatives and analogs were compared at graded dietary concentrations. Linear response was closely approximated for concentrations below those yielding maximum growth. Derivatization of L-methionine generally lowered potency, calculated as the ratio of the slopes of the two dose-response curves. However, the three isomeric dipeptides L-L-, L-D- and D-L-methionylmethionine, N-acetyl- and N-formyl-L-methionine, L-methionine sulfoxide and D-methionine were well utilized. The double derivative N-acetyl-L-methionine sulfoxide reduced potency below 60%. D-Methionine sulfoxide, N-acetyl-D-methionine and D-methionyl-D-methionine had potencies between 4 and 40%. The calcium salts of L- and D-alpha-hydroxy analogs of methionine had potencies of 55.4 and 85.7%, respectively. Several of the analogs were less growth-inhibiting or toxic at high concentrations in the diet than was L-methionine. These results imply that some methionine dipeptides or analogs may be better candidates for fortifying foods than L-methionine. Possible biochemical pathways for the utilization of methionine derivatives and analogs are also described. PMID:3351635

  15. Aerobic Microbial Cometabolism of Benzothiophene and 3-Methylbenzothiophene

    PubMed Central

    Fedorak, Phillip M.; Grbić-Galić, Dunja

    1991-01-01

    A culture enriched by growth on 1-methylnaphthalene was used to study the aerobic biotransformations of benzothiophene and 3-methylbenzothiophene. Neither of the sulfur heterocyclic compounds would support growth, but they were transformed by the culture growing on 1-methylnaphthalene or glucose or peptone. Cometabolism of benzothiophene yielded benzothiophene-2,3-dione, whereas that of 3-methylbenzothiophene yielded 3-methylbenzothiophene sulfoxide and the corresponding sulfone. The identities of the dione and sulfone were verified by comparison with authentic standards. The identity of the sulfoxide was surmised from gas chromatography-mass spectrometry and gas chromatography- Fourier transform infrared spectroscopy results. Oxidation preferentially occurred at carbons 2 and 3 in benzothiophene, but when carbon 3 was substituted with a methyl group, as in 3-methylbenzothiophene, the sulfur atom was oxygenated. The predominant microorganism in the enrichment culture was a Pseudomonas strain, designated BT1, which mineralized aromatic but not aliphatic hydrocarbons. This isolate cometabolized benzothiophene and 3-methylbenzothiophene. There was no evidence that it could metabolize 3-methylbenzothiophene sulfone. When 3-methylbenzothiophene was added to Prudhoe Bay crude oil, the sulfur heterocycle was oxidized to its sulfoxide and sulfone by strain BT1 as it grew on the aromatic hydrocarbons in the crude oil. Benzothiophene-2,3-dione was found to be chemically unstable when incubated with Prudhoe Bay crude oil. Thus its formation from benzothiophene in the presence of crude oil could not be determined. PMID:16348471

  16. Effect of sample transport systems on survival of bacteria in ground beef.

    PubMed Central

    Kotula, A W; Pierson, M D; Emswiler, B S; Guilfoyle, J R

    1979-01-01

    The effects of two transport systems and cryoprotective agents on the survival of bacteria in ground beef samples were evaluated. Survival of Clostridium perfringens in ground beef samples after simulated transport (72 h) was higher (about 99%) in Dry Ice than in Trans Temp shipping units (-3 degrees C). There were no significant differences between the two transport systems in survival of coliforms, Escherichia coli, Staphylococcus aureus, or aerobic bacteria. Mixing ground beef samples at a ratio of 1:1 (wt/vol) with 10, 20, or 30% buffered solutions of dimethyl sulfoxide or glycerol before freezing improved the survival of C. perfringens and coliforms in both transport systems. Recovery of E. coli was significantly higher with the addition of 10% dimethyl sulfoxide before Dry Ice transport. Addition of 10% dimethyl sulfoxide resulted in a 100% recovery of both S. aureus and aerobic bacteria from ground beef after simulated transport in Trans Temp shipping units. The use of cryoprotective agents can improve the survival of bacteria during transport of ground beef samples. PMID:232392

  17. Mechanisms of Methylene Blue Degradation in Three-dimensionally Integrated Micro-solution Plasma

    NASA Astrophysics Data System (ADS)

    Nomura, Ayano; Hayashi, Yui; Tanaka, Kenji; Shirafuji, Tatsuru; Goto, Motonobu

    2015-09-01

    Plasma in aqueous solution has attracted much attention because they are expected to have possibilities to solve water-related environmental issues. In such application-oriented researches, degradation of methylene blue (MB) or other organic dyes has been widely used for investigating the effects of the plasma treatment on the water with organic contaminants. However, there are few reports on the detailed analysis of the products after the plasma treatment of MB aqueous solution for understanding mechanisms of the degradation processes. We have hence analyzed our degradation products using matrix-assisted laser desorption ionization time-of-flight (MALDI-TOF) mass spectrometry. We have performed the MB degradation in three-dimensionally integrated micro-solution plasma, which has shown 16-fold higher performance in MB degradation than conventional solution plasma. The results of MALDI-TOF mass spectrometry have indicated the formation of sulfoxides in the first stage of the degradation. Then, the methyl groups on the sulfoxides are partially oxidized. The sulfoxides are separated to form two benzene derivatives after that. Finally, weak functional groups are removed from the benzene derivatives.

  18. A study to determine the efficacy of treatments for hydrofluoric acid burns.

    PubMed

    Seyb, S T; Noordhoek, L; Botens, S; Mani, M M

    1995-01-01

    Hydrofluoric acid burns are characterized by progressive tissue destruction and severe pain. Fluoride ion chelators, such as salts of calcium and magnesium, have been used to treat these burns. This study was designed to compare the efficacy of several treatment methods that involve the use of these salts. Standard hydrofluoric acid burns were produced on the shaved hindquarters of rats. After being rinsed with water, the chemical burns were treated by one of seven experimental methods. The progress of the chemical burn damage was observed for 1 week by measuring the surface areas of the burns. Calcium gluconate burn jelly, 20% calcium gluconate in water, and 50% aqueous dimethyl sulfoxide did not significantly slow the spread of the burn area. However, subcutaneous injections of calcium gluconate or magnesium sulfate and topical applications of calcium gluconate in a solution of dimethyl sulfoxide significantly slowed the progress of the burns during the first 24 hours and enhanced tissue recovery for the remainder of the observation period. These results indicate that subcutaneous injections of magnesium or calcium salts appear to be more effective than conventional topical applications in the treatment of hydrofluoric acid burns. More significantly, topically applied calcium gluconate combined with a penetration enhancer, such as dimethyl sulfoxide, is as effective as injection treatments in reducing damage caused by hydrofluoric acid. PMID:7673304

  19. Antimony leaching in plastics from waste electrical and electronic equipment (WEEE) with various acids and gamma irradiation

    SciTech Connect

    Tostar, Sandra; Stenvall, Erik; Boldizar, Antal; Foreman, Mark R. St. J.

    2013-06-15

    Highlights: • We have proposed a method to recover antimony from electronic plastics. • The most efficient acid solution was sodium hydrogen tartrate in dimethyl sulfoxide. • Gamma irradiation did not influence the antimony leaching ability. - Abstract: There has been a recent interest in antimony since the availability in readily mined areas is decreasing compared to the amounts used. It is important in many applications such as flame retardants and in the production of polyester, which can trigger an investigation of the leachability of antimony from plastics using different acids. In this paper, different types of acids are tested for their ability to leach antimony from a discarded computer housing, made of poly(acrylonitrile butadiene styrene), which is a common plastic type used in electrical and electronic equipment. The acid solutions included sodium hydrogen tartrate (0.5 M) dissolved in either dimethyl sulfoxide or water (at ca. 23 °C and heated to ca. 105 °C). The metal content after leaching was determined by inductively coupled plasma optical emission spectroscopy. The most efficient leaching medium was the heated solution of sodium hydrogen tartrate in dimethyl sulfoxide, which leached almost half of the antimony from the poly(acrylonitrile butadiene styrene). Gamma irradiation, which is proposed to improve the mechanical properties in plastics, was used here to investigate the influence of antimony leaching ability. No significant change in the amount of leached antimony could be observed.

  20. A dielectric barrier discharge terminally inactivates RNase A by oxidizing sulfur-containing amino acids and breaking structural disulfide bonds

    NASA Astrophysics Data System (ADS)

    Lackmann, J.-W.; Baldus, S.; Steinborn, E.; Edengeiser, E.; Kogelheide, F.; Langklotz, S.; Schneider, S.; Leichert, L. I. O.; Benedikt, J.; Awakowicz, P.; Bandow, J. E.

    2015-12-01

    RNases are among the most stable proteins in nature. They even refold spontaneously after heat inactivation, regaining full activity. Due to their stability and universal presence, they often pose a problem when experimenting with RNA. We investigated the capabilities of nonthermal atmospheric-pressure plasmas to inactivate RNase A and studied the inactivation mechanism on a molecular level. While prolonged heating above 90 °C is required for heat inactivating RNase A, direct plasma treatment with a dielectric barrier discharge (DBD) source caused permanent inactivation within minutes. Circular dichroism spectroscopy showed that DBD-treated RNase A unfolds rapidly. Raman spectroscopy indicated methionine modifications and formation of sulfonic acid. A mass spectrometry-based analysis of the protein modifications that occur during plasma treatment over time revealed that methionine sulfoxide formation coincides with protein inactivation. Chemical reduction of methionine sulfoxides partially restored RNase A activity confirming that sulfoxidation is causal and sufficient for RNase A inactivation. Continued plasma exposure led to over-oxidation of structural disulfide bonds. Using antibodies, disulfide bond over-oxidation was shown to be a general protein inactivation mechanism of the DBD. The antibody’s heavy and light chains linked by disulfide bonds dissociated after plasma exposure. Based on their ability to inactivate proteins by oxidation of sulfur-containing amino acids and over-oxidation of disulfide bonds, DBD devices present a viable option for inactivating undesired or hazardous proteins on heat or solvent-sensitive surfaces.

  1. Kinetically controlled synthesis of Au102(SPh)44 nanoclusters and catalytic application.

    PubMed

    Chen, Yongdong; Wang, Jin; Liu, Chao; Li, Zhimin; Li, Gao

    2016-05-21

    We here explore a kinetically controlled synthetic protocol for preparing solvent-solvable Au102(SPh)44 nanoclusters which are isolated from polydispersed gold nanoclusters by solvent extraction and size exclusion chromatography (SEC). The as-obtained Au102(SPh)44 nanoclusters are determined by matrix-assisted laser desorption ionization (MALDI) and electrospray ionization (ESI) mass spectrometry, in conjunction with UV-vis spectroscopy and thermogravimetric analysis (TGA). However, Au99(SPh)42, instead of Au102(SPh)44, is yielded when the polydispersed gold nanoclusters are etched in the presence of excess thiophenol under thermal conditions (e.g., 80 °C). Interestingly, the Au102(SPh)44 nanoclusters also can convert to Au99(SPh)42 with equivalent thiophenol ligands, evidenced by the analyses of UV-vis and MALDI mass spectrometry. Finally, the TiO2-supported Au102(SPh)44 nanocluster catalyst is investigated in the selective oxidation of sulfides into sulfoxides by the PhIO oxidant and gives rise to high catalytic activity (e.g., 80-99% conversion of R-S-R' sulfides with 96-99% selectivity for R-S([double bond, length as m-dash]O)-R' sulfoxides). The Au102(SPh)44/TiO2 catalyst also shows excellent recyclability in the sulfoxidation process. PMID:26758553

  2. Further studies on cation clock reactions in glycosylation: observation of a configuration specific intramolecular sulfenyl transfer and isolation and characterization of a tricyclic acetal.

    PubMed

    Huang, Min; Furukawa, Takayuki; Retailleau, Pascal; Crich, David; Bohé, Luis

    2016-06-01

    The use of the 2-O-(2-trimethylsilylmethallyl) group as intramolecular nucleophile and cation clock reaction in the glucopyranose series depends on the nature of the glycosyl donor. As previously reported, with trichloroacetimidates the anticipated intramolecular Sakurai reaction proceeds efficiently and is an effective clock, whereas with sulfoxides complications arise. The source of these complications is now shown to be an intramolecular sulfenyl transfer reaction between the tethered allylsilane and the activated sulfoxide. These results illustrate how a different unimolecular clock reaction may be required for a given cation when it is generated from different donors in order to avoid side reactions. The synthesis and cyclization of a 2-O-(3-hydroxypropyl) glucopyranosyl sulfoxide leading on activation to the formation of a trans-fused acetal is also described. The formation of this crystallographically-established trans-fused acetal is discussed in terms of the high effective concentration of the intramolecular nucleophile which leads to a high degree of a SN2 character in the displacement of the α-glucosyl triflate or at the level of the corresponding α-CIP. The possible use of such intramolecular alcohols as clock reactions and their limitations is discussed. PMID:27085740

  3. Redox reactions in mammalian spermatogenesis and the potential targets of reactive oxygen species under oxidative stress

    PubMed Central

    Fujii, Junichi; Imai, Hirotaka

    2014-01-01

    Reduction-oxidation (Redox) reactions are ubiquitous mechanisms for vital activities in all organisms, and they play pivotal roles in the regulation of spermatogenesis as well. Here we focus on 3 redox-involved processes that have drawn much recent attention: the regulation of signal transduction by reactive oxygen species (ROS) such as hydrogen peroxide, oxidative protein folding in the endoplasmic reticulum (ER), and sulfoxidation of protamines during sperm chromatin condensation. The first 2 of these processes are emerging topics in cell biology and are applicable to most living cells, which includes spermatogenic cells. The roles of ROS in signal transduction have been elucidated in the last 2 decades and have received broad attention, most notably from the viewpoint of the proper control of mitotic signals. Redox processes in the ER are important because this is the organelle where secretory and membrane proteins are synthesized and proceed toward their functional structure, so that malfunction of the ER affects not only the involved cells but also the accepting cells of the secreted proteins in multicellular organisms. Sulfoxidation is the third of these processes, and the sulfoxidation of chromatin is a unique process in sperm maturation. During recent sulfoxidase research, GPX4 has emerged as a promising enzyme that plays essential roles in the production of fertile sperm, but the involvement of other redox proteins is also becoming evident. Because the molecules involved in the redox reactions are prone to oxidation, they can be sensitive to oxidative damage, which makes them potential targets for antioxidant therapy. PMID:26413390

  4. Biotransformation of enoximone, a new cardiotonic agent, in man and laboratory animals

    SciTech Connect

    Chan, K.Y.; Lang, J.F.; Coutant, J.E.; Okerholm, R.A.

    1986-03-01

    Enoximone, 1,3-dihydro-4-methyl-5-(4-(methylthio)benzoyl)-2H-imidazol-2-one is a new cardiotonic agent which is currently undergoing clinical evaluation in patients with congestive heart failure. Biotransformation of enoximone was studied in man, rat, monkey and dog by means of /sup 14/C-labelled material, HPLC and GC/MS techniques. Metabolic conversions were qualitatively similar in all species. The parent compound was found to be extensively metabolized. Generally less than 1% of the dose was recovered as enoximone in urine. The sulfoxide was the major metabolite in all species, accounting for over 90% of the dose in the urine of the monkey and greater than 75% in man and the rat. The sulfone was present in trace quantities, except in the rats, where it accounted for 5-8% of the dose. A glycine conjugate of 4-methylthiobenzoic acid was also identified as a urinary metabolite; and the dog seems to favor this pathway more than the other 3 species; as it accounted for over 30% of the dose. The two stereoisomers of synthetic sulfoxide were separated by HPLC, and examination of urine from patients receiving enoximone therapy suggested that the metabolic conversion of enoximone to sulfoxide was stereospecific, as only one isomeric peak was observed in the HPLC system.

  5. Biological and nonbiological modifications of carbamates

    PubMed Central

    Knaak, James B.

    1971-01-01

    Methylcarbamate insecticides undergo hydrolysis, oxidation, dealkylation, and conjugation in animals, plants, and insects to form similar or identical products. Carbaryl is hydroxylated in biological systems to form hydroxy, dihydro-dihydroxy, and N-hydroxymethyl carbaryl and is hydrolysed to form 1-naphthol. The products are conjugated, stored, or excreted. Carbofuran is hydroxylated at the 3 position and propoxur at the 5 position to form hydroxylated derivatives. N-hydroxymethyl derivatives of these two carbamates may also be formed. Hydrolysis appears to be the major metabolic pathway of carbofuran in the animal. Aldicarb is oxidized to its sulfoxide and then hydrolysed to the oxime sulfoxide in animals and plants. Plants hydrolyse the oxime sulfoxide to form the corresponding aldehyde, which is an intermediate in the formation of 2-methyl-2-(methyl-sulfinyl)propanol. Methomyl, which is structurally similar to aldicarb, is metabolized in plants to acetonitrile, carbon dioxide, and methylamine. Bux and Meobal undergo hydrolysis and hydroxylation to form N-hydroxy methylcarbamates, as well as hydroxybutylphenyl and hydroxymethylphenyl methylcarbamates. Zectran, which contains a dimethylamino group, is converted to the methylamino, amino, and methylformamido derivatives by insects and plants. In soil and water, methylcarbamate insecticides are hydrolysed to their respective phenols or oximes. PMID:4999481

  6. Tubular transport and metabolism of cimetidine in chicken kidneys

    SciTech Connect

    Rennick, B.; Ziemniak, J.; Smith, I.; Taylor, M.; Acara, M.

    1984-02-01

    Renal tubular transport and renal metabolism of (/sup 14/C)cimetidine (CIM) were investigated by unilateral infusion into the renal portal circulation in chickens (Sperber technique). (/sup 14/C)CIM was actively transported at a rate 88% that of simultaneously infused p-aminohippuric acid, and its transport was saturable. The following organic cations competitively inhibited the tubular transport of (/sup 14/C)CIM with decreasing potency: CIM, ranitidine, thiamine, procainamide, guanidine and choline. CIM inhibited the transport of (/sup 14/C)thiamine, (/sup 14/C)amiloride and (/sup 14/C)tetraethylammonium. During CIM infusion, two renal metabolites, CIM sulfoxide and hydroxymethylcimetidine, were found in urine. When CIM sulfoxide was infused, its transport efficiency was 32% and not saturable. CIM sulfoxide did ot inhibit the simultaneous renal tubular transport of p-aminohippuric acid or tetraethylammonium. CIM is transported by the organic cation transport system and the kidney metabolizes CIM. Transport of CIM and other cationic drugs could produce a drug interaction to alter drug excretion.

  7. Biological and physicochemical properties of the lipopolysaccharide of Chromatium vinosum.

    PubMed Central

    Hurlbert, R E; Hurlbert, I M

    1977-01-01

    The lipopolysaccharide (LPS) of Chromatium vinosum has anticomplementary activity. This anticomplementary activity is destroyed by alkaline digestion of the LPS and is suppressed by both Mg2+ and Ca2+ ions. Treatment of the LPS with ethylenediaminetetraacetic acid, sodium deoxycholate, or dimethyl sulfoxide did not affect its toxicity toward mice; however, alkaline-treated LPS was not toxic. Treatment of the LPS with sodium deoxycholate, dimethyl sulfoxide, or sodium dodecyl sulfate resulted in reversible dissociation into subunits. Aggregation of the subunits into the original form was achieved by removing the dispersing agent by dialysis against distilled water followed by freezing and thawing. Electron micrographs of phenol-extracted LPS showed long filaments. Electron micrographs of sodium deoxycholate- and sodium dodecyl sulfate-treated and dialyzed LPS showed a mixture of small subunits and short filaments, whereas dimethyl sulfoxide-treated and dialyzed LPS contained only small ovoid spheres. The LPS produced an ordered series of multiple bands on sodium dodecyl sulfate-polyacrylamide gel electrophoresis. A similar banding pattern was observed for Salmonella abortus-equi and Proteus mirabilis LPS. The C. vinosum LPS appears to be mitogenic for mouse spleen cells. Images PMID:892903

  8. Sulfur monoxide transfer from peri-substituted trisulfide-2-oxides to dienes: substituent effects, mechanistic studies and application in thiophene synthesis.

    PubMed

    Grainger, Richard S; Patel, Bhaven; Kariuki, Benson M; Male, Louise; Spencer, Neil

    2011-04-20

    Three peri-substituted trisulfide-2-oxides are prepared by treatment of 1,8-naphthalene dithiols with thionyl chloride and pyridine. The 1,2,3-trithiane-2-oxide ring adopts a sofa conformation in the solid state, with a pseudoaxial oxygen and evidence of ring strain (peri-interaction). Heating the trisulfide-2-oxides in the presence of a diene results in formal sulfur monoxide (SO) transfer to form unsaturated cyclic sulfoxides, along with a recyclable 1,8-naphthalene disulfide. The presence of o-methoxy or o-tert-butyl substituents on the naphthalene ring lowers the temperature and increases the rate at which SO transfer occurs. Trapping experiments and kinetic studies are consistent with the generation of triplet SO, followed by in situ trapping by diene. Transfer of SO also occurs upon irradiation at room temperature, but yields of sulfoxide are lower. Dehydration of the sulfoxides under Pummerer conditions gives thiophenes, including the naturally occurring thioperillene. Two dienes form thiophenes directly under the SO transfer conditions. The methodology is applied in a formal synthesis of the antiplatelet medication Plavix. PMID:21443185

  9. Crystal structure of 16-ferrocenylmethyl-3β-hydroxy-estra-1,3,5(10)-trien-17-one: a potential chemotherapeutic drug.

    PubMed

    Carmona-Negrón, José A; Flores-Rivera, Mariola M; Díaz-Reyes, Zaibeth; Moore, Curtis E; Rheigold, Arnold L; Meléndez, Enrique

    2016-06-01

    A new ferrocene complex, 16-ferrocenylmethyl-3β-hy-droxy-estra-1,3,5(10)-trien-17-one dimethyl sulfoxide monosolvate, [Fe(C5H5)(C24H27O2)]·C2H6OS, has been synthesized and structurally characterized by single-crystal X-ray diffraction techniques. The mol-ecule crystallizes in the space group P21 with one mol-ecule of dimethyl sulfoxide. A hydrogen bond links the phenol group and the dimethyl sulfoxide O atom, with an O⋯O distance of 2.655 (5) Å. The ferrocene group is positioned in the β face of the estrone moiety, with an O-C-C-C torsion angle of 44.1 (5)°, and the carbonyl bond length of the hormone moiety is 1.216 (5) Å, typical of a C=O double bond. The average Fe-C bond length of the substituted Cp ring [Fe-C(Cp*)] is similar to that of the unsubstituted one [Fe-C(Cp)], i.e. 2.048 (3) versus 2.040 (12) Å. The structure of the complex is compared with those of estrone and eth-oxy-methyl-estrone. PMID:27308062

  10. Crystal structure of 16-ferrocenylmethyl-3β-hydroxy­estra-1,3,5(10)-trien-17-one: a potential chemotherapeutic drug

    PubMed Central

    Carmona-Negrón, José A.; Flores-Rivera, Mariola M.; Díaz-Reyes, Zaibeth; Moore, Curtis E.; Rheigold, Arnold L.; Meléndez, Enrique

    2016-01-01

    A new ferrocene complex, 16-ferrocenylmethyl-3β-hy­droxy­estra-1,3,5(10)-trien-17-one dimethyl sulfoxide monosolvate, [Fe(C5H5)(C24H27O2)]·C2H6OS, has been synthesized and structurally characterized by single-crystal X-ray diffraction techniques. The mol­ecule crystallizes in the space group P21 with one mol­ecule of dimethyl sulfoxide. A hydrogen bond links the phenol group and the dimethyl sulfoxide O atom, with an O⋯O distance of 2.655 (5) Å. The ferrocene group is positioned in the β face of the estrone moiety, with an O—C—C—C torsion angle of 44.1 (5)°, and the carbonyl bond length of the hormone moiety is 1.216 (5) Å, typical of a C=O double bond. The average Fe—C bond length of the substituted Cp ring [Fe—C(Cp*)] is similar to that of the unsubstituted one [Fe—C(Cp)], i.e. 2.048 (3) versus 2.040 (12) Å. The structure of the complex is compared with those of estrone and eth­oxy­methyl­estrone. PMID:27308062

  11. Toxicokinetics of acrylamide in rats and humans following single oral administration of low doses

    SciTech Connect

    Kopp, Eva Katharina; Dekant, Wolfgang

    2009-03-01

    The rodent carcinogen acrylamide (AA) is formed during preparation of starch-containing foods. AA is partly metabolized to the genotoxic epoxide glycidamide (GA). After metabolic processing, the mercapturic acids N-acetyl-S-(2-carbamoylethyl)-L-cysteine (AAMA), rac-N-acetyl-S-(2-carbamoyl-2-hydroxyethyl)-L-cysteine (GAMA) and rac-N-acetyl-S-(1-carbamoyl-moyl-2-hydroxyethyl)-L-cysteine (iso-GAMA) are excreted with urine. In humans, AAMA can be sulfoxidized to AAMA-sulfoxide. The aim of this study was to assess potential species-differences in AA-toxicokinetics in rats and humans after single oral administration of doses similar to the daily human dietary exposure. Male Fischer 344 rats (n = 5/dose group) were administered 20 and 100 {mu}g/kg b.w. {sup 13}C{sub 3}-AA in deionized water via oral gavage. Human subjects (n = 3/gender) were orally administered 0.5 and 20 {mu}g/kg b.w. {sup 13}C{sub 3}-AA with drinking water. Urine samples were collected in intervals for 96 and 94 h, respectively. Urinary concentrations of {sup 13}C{sub 3}-AAMA, {sup 13}C{sub 3}-GAMA and {sup 13}C{sub 3}-AAMA-sulfoxide were monitored by liquid chromatography-tandem mass spectrometry. The recovered urinary metabolites accounted for 66.3% and 70.5% of the 20 and 100 {mu}g/kg b.w. doses in rats and for 71.3% and 70.0% of the 0.5 and 20 {mu}g/kg b.w. doses in humans. In rats, {sup 13}C{sub 3}-AAMA accounted for 33.6% and 38.8% of dose and 32.7% and 31.7% of dose was recovered as {sup 13}C{sub 3}-GAMA; {sup 13}C{sub 3}-AAMA-sulfoxide was not detected in rat urine. In humans, {sup 13}C{sub 3}-AAMA, {sup 13}C{sub 3}-GAMA and {sup 13}C{sub 3}-AAMA-sulfoxide accounted for 51.7% and 49.2%, 6.3% and 6.4% and 13.2% and 14.5% of the applied dose, respectively. The obtained results suggest that the extent of AA bioactivation to GA in humans is lower than in rodents.

  12. Garlic γ-glutamyl transpeptidases that catalyze deglutamylation of biosynthetic intermediate of alliin

    PubMed Central

    Yoshimoto, Naoko; Yabe, Ayami; Sugino, Yuka; Murakami, Soichiro; Sai-ngam, Niti; Sumi, Shin-ichiro; Tsuneyoshi, Tadamitsu; Saito, Kazuki

    2015-01-01

    S-Alk(en)yl-L-cysteine sulfoxides are pharmaceutically important secondary metabolites produced by plants that belong to the genus Allium. Biosynthesis of S-alk(en)yl-L-cysteine sulfoxides is initiated by S-alk(en)ylation of glutathione, which is followed by the removal of glycyl and γ-glutamyl groups and S-oxygenation. However, most of the enzymes involved in the biosynthesis of S-alk(en)yl-L-cysteine sulfoxides in Allium plants have not been identified. In this study, we identified three genes, AsGGT1, AsGGT2, and AsGGT3, from garlic (Allium sativum) that encode γ-glutamyl transpeptidases (GGTs) catalyzing the removal of the γ-glutamyl moiety from a putative biosynthetic intermediate of S-allyl-L-cysteine sulfoxide (alliin). The recombinant proteins of AsGGT1, AsGGT2, and AsGGT3 exhibited considerable deglutamylation activity toward a putative alliin biosynthetic intermediate, γ-glutamyl-S-allyl-L-cysteine, whereas these proteins showed very low deglutamylation activity toward another possible alliin biosynthetic intermediate, γ-glutamyl-S-allyl-L-cysteine sulfoxide. The deglutamylation activities of AsGGT1, AsGGT2, and AsGGT3 toward γ-glutamyl-S-allyl-L-cysteine were elevated in the presence of the dipeptide glycylglycine as a γ-glutamyl acceptor substrate, although these proteins can act as hydrolases in the absence of a proper acceptor substrate, except water. The apparent Km values of AsGGT1, AsGGT2, and AsGGT3 for γ-glutamyl-S-allyl-L-cysteine were 86 μM, 1.1 mM, and 9.4 mM, respectively. Subcellular distribution of GFP-fusion proteins transiently expressed in onion cells suggested that AsGGT2 localizes in the vacuole, whereas AsGGT1 and AsGGT3 possess no apparent transit peptide for localization to intracellular organelles. The different kinetic properties and subcellular localizations of AsGGT1, AsGGT2, and AsGGT3 suggest that these three GGTs may contribute differently to the biosynthesis of alliin in garlic. PMID:25620969

  13. Efficacy of a metalloproteinase inhibitor in spinal cord injured dogs.

    PubMed

    Levine, Jonathan M; Cohen, Noah D; Heller, Michael; Fajt, Virginia R; Levine, Gwendolyn J; Kerwin, Sharon C; Trivedi, Alpa A; Fandel, Thomas M; Werb, Zena; Modestino, Augusta; Noble-Haeusslein, Linda J

    2014-01-01

    Matrix metalloproteinase-9 is elevated within the acutely injured murine spinal cord and blockade of this early proteolytic activity with GM6001, a broad-spectrum matrix metalloproteinase inhibitor, results in improved recovery after spinal cord injury. As matrix metalloproteinase-9 is likewise acutely elevated in dogs with naturally occurring spinal cord injuries, we evaluated efficacy of GM6001 solubilized in dimethyl sulfoxide in this second species. Safety and pharmacokinetic studies were conducted in naïve dogs. After confirming safety, subsequent pharmacokinetic analyses demonstrated that a 100 mg/kg subcutaneous dose of GM6001 resulted in plasma concentrations that peaked shortly after administration and were sustained for at least 4 days at levels that produced robust in vitro inhibition of matrix metalloproteinase-9. A randomized, blinded, placebo-controlled study was then conducted to assess efficacy of GM6001 given within 48 hours of spinal cord injury. Dogs were enrolled in 3 groups: GM6001 dissolved in dimethyl sulfoxide (n = 35), dimethyl sulfoxide (n = 37), or saline (n = 41). Matrix metalloproteinase activity was increased in the serum of injured dogs and GM6001 reduced this serum protease activity compared to the other two groups. To assess recovery, dogs were a priori stratified into a severely injured group and a mild-to-moderate injured group, using a Modified Frankel Scale. The Texas Spinal Cord Injury Score was then used to assess long-term motor/sensory function. In dogs with severe spinal cord injuries, those treated with saline had a mean motor score of 2 (95% CI 0-4.0) that was significantly (P<0.05; generalized linear model) less than the estimated mean motor score for dogs receiving dimethyl sulfoxide (mean, 5; 95% CI 2.0-8.0) or GM6001 (mean, 5; 95% CI 2.0-8.0). As there was no independent effect of GM6001, we attribute improved neurological outcomes to dimethyl sulfoxide, a pleotropic agent that may target diverse secondary pathogenic

  14. Bioactivation of clopidogrel and prasugrel: factors determining the stereochemistry of the thiol metabolite double bond.

    PubMed

    Dansette, Patrick M; Levent, Dan; Hessani, Assia; Mansuy, Daniel

    2015-06-15

    The antithrombotics of the tetrahydrothienopyridine series, clopidogrel and prasugrel, are prodrugs that must be metabolized in two steps to become pharmacologically active. The first step is the formation of a thiolactone metabolite. The second step is a further oxidation with the formation of a thiolactone sulfoxide whose hydrolytic opening leads to a sulfenic acid that is eventually reduced into the corresponding active cis thiol. Very few data were available on the formation of the isomer of the active cis thiol having a trans configuration of the double bond, the most striking result in that regard being that both cis and trans thiols were formed upon the metabolism of clopidogrel by human liver microsomes in the presence of glutathione (GSH), whereas only the cis thiol was detected in the sera of patients treated with this drug. This article shows that trans thiols are also formed upon the microsomal metabolism of prasugrel or its thiolactone metabolite in the presence of GSH and that metabolites having the trans configuration of the double bond are only formed when microsomal incubations are done in the presence of thiols, such as GSH, N-acetyl-cysteine, and mercaptoethanol. Intermediate formation of thioesters resulting from the reaction of GSH with the thiolactone sulfoxide metabolite appears to be responsible for trans thiol formation. Addition of human liver cytosol to the microsomal incubations led to a dramatic decrease of the formation of the trans thiol metabolites. These data suggest that cytosolic esterases would accelerate the hydrolytic opening of thiolactone sulfoxide intermediates and disfavor the formation of thioesters resulting from the reaction of these intermediates with GSH that is responsible for trans isomer formation. This would explain why trans thiols have not been detected in the sera of patients treated with clopidogrel. PMID:25970225

  15. Gender differences in methionine accumulation and metabolism in freshly isolated mouse hepatocytes: Potential roles in toxicity

    SciTech Connect

    Dever, Joseph T.; Elfarra, Adnan A.

    2009-05-01

    L-Methionine (Met) is hepatotoxic at high concentrations. Because Met toxicity in freshly isolated mouse hepatocytes is gender-dependent, the goal of this study was to assess the roles of Met accumulation and metabolism in the increased sensitivity of male hepatocytes to Met toxicity compared with female hepatocytes. Male hepatocytes incubated with Met (30 mM) at 37 {sup o}C exhibited higher levels of intracellular Met at 0.5, 1.0, and 1.5 h, respectively, compared to female hepatocytes. Conversely, female hepatocytes had higher levels of S-adenosyl-L-methionine compared to male hepatocytes. Female hepatocytes also exhibited higher L-methionine-L-sulfoxide levels relative to control hepatocytes, whereas the increases in L-methionine-D-sulfoxide (Met-D-O) levels were similar in hepatocytes of both genders. Addition of aminooxyacetic acid (AOAA), an inhibitor of Met transamination, significantly increased Met levels at 1.5 h and increased Met-D-O levels at 1.0 and 1.5 h only in Met-exposed male hepatocytes. No gender differences in cytosolic Met transamination activity by glutamine transaminase K were detected. However, female mouse liver cytosol exhibited higher methionine-DL-sulfoxide (MetO) reductase activity than male mouse liver cytosol at low (0.25 and 0.5 mM) MetO concentrations. Collectively, these results suggest that increased cellular Met accumulation, decreased Met transmethylation, and increased Met and MetO transamination in male mouse hepatocytes may be contributing to the higher sensitivity of the male mouse hepatocytes to Met toxicity in comparison with female mouse hepatocytes.

  16. ADVANCED OXIDATION PROCESS

    SciTech Connect

    Colin P. Horwitz; Terrence J. Collins

    2003-10-22

    The design of new, high efficiency and cleaner burning engines is strongly coupled with the removal of recalcitrant sulfur species, dibenzothiophene and its derivatives, from fuels. Oxidative desulfurization (ODS) wherein these dibenzothiophene derivatives are oxidized to their corresponding sulfoxides and sulfones is an approach that has gained significant attention. Fe-TAML{reg_sign} activators of hydrogen peroxide (TAML is Tetra-Amido-Macrocyclic-Ligand) convert in a catalytic process dibenzothiophene and its derivatives to the corresponding sulfoxides and sulfones rapidly at moderate temperatures (60 C) and ambient pressure. The reaction can be performed in both an aqueous system containing an alcohol (methanol, ethanol, or t-butanol) to solubilize the DBT and in a two-phase hydrocarbon/aqueous system where the alcohol is present in both phases and facilitates the oxidation. Under a consistent set of conditions using the FeBF{sub 2} TAML activator, the degree of conversion was found to be t-butanol > methanol > ethanol. In the cases of methanol and ethanol, both the sulfoxide and sulfone were observed while for t-butanol only the sulfone was detected. In the two-phase system, the alcohol may function as an inverse phase transfer agent. The oxidation was carried out using two different TAML activators. In homogeneous solution, approximately 90% oxidation of the DBT could be achieved using the prototype TAML activator, FeB*, by sonicating the solution at near room temperature. In bi-phasic systems conversions as high as 50% were achieved using the FeB* TAML activator and hydrogen peroxide at 100 C. The sonication method yielded only {approx}6% conversion but this may have been due to mixing.

  17. Substrate and Cofactor Range Differences of Two Cysteine Dioxygenases from Ralstonia eutropha H16

    PubMed Central

    Wenning, Leonie; Stöveken, Nadine; Wübbeler, Jan Hendrik

    2015-01-01

    Cysteine dioxygenases (Cdos), which catalyze the sulfoxidation of cysteine to cysteine sulfinic acid (CSA), have been extensively studied in eukaryotes because of their roles in several diseases. In contrast, only a few prokaryotic enzymes of this type have been investigated. In Ralstonia eutropha H16, two Cdo homologues (CdoA and CdoB) have been identified previously. In vivo studies showed that Escherichia coli cells expressing CdoA could convert 3-mercaptopropionate (3MP) to 3-sulfinopropionate (3SP), whereas no 3SP could be detected in cells expressing CdoB. The objective of this study was to confirm these findings and to study both enzymes in detail by performing an in vitro characterization. The proteins were heterologously expressed and purified to apparent homogeneity by immobilized metal chelate affinity chromatography (IMAC). Subsequent analysis of the enzyme activities revealed striking differences with regard to their substrate ranges and their specificities for the transition metal cofactor, e.g., CdoA catalyzed the sulfoxidation of 3MP to a 3-fold-greater extent than the sulfoxidation of cysteine, whereas CdoB converted only cysteine. Moreover, the dependency of the activities of the Cdos from R. eutropha H16 on the metal cofactor in the active center could be demonstrated. The importance of CdoA for the metabolism of the sulfur compounds 3,3′-thiodipropionic acid (TDP) and 3,3′-dithiodipropionic acid (DTDP) by further converting their degradation product, 3MP, was confirmed. Since 3MP can also function as a precursor for polythioester (PTE) synthesis in R. eutropha H16, deletion of cdoA might enable increased synthesis of PTEs. PMID:26590284

  18. Use of hot formaldehyde fixative in processing plant-parasitic nematodes for electron microscopy.

    PubMed

    Zeikus, J A; Aldrich, H C

    1975-07-01

    A preparative technique is formulated for processing plant-parasitic nematodes of the order Tylenchida for electron microscopy. A population of Dolichodorus heterocephalus is used as test objects. One and a half grams of paraformaldehyde are dissolved in 25 ml of water at 60 C. Five drops of 1 N sodium hydroxide are added to clear the solution, which is then cooled to room temperature. Two and a half milliliters of 25% glutaraldehyde are added with 23 ml 0.1 M phosphate buffer, pH 7.3, and 0.2 M with respect to sucrose. The final solution contains 3% formaldehyde and 1% glutaraldehyde and is pH 7.2. It is heated to 70 C, poured over specimens, and allowed to cool to 4 C in 2 hr. The nematodes are then incised in a fixative containing 2% glutaraldehyde and 5% dimethyl sulfoxide at 4 C for 16-24 hr. Five milliliters of 25% glutaraldehyde and 2.5 ml of dimethyl sulfoxide are combined in 17.5 ml of water. Twenty-five milliliters of phosphate buffer (supplemented as above) are added. The final pH is 7.2. The glutaraldehyde, aided by dimethyl sulfoxide, uniformly and permanently fixes the nematode tissues. The specimens are embedded in agar. Following a 30-min buffer wash (4 C) they are postfixed in buffered 2% osmium tetroxide for 2 hr at room temperature, washed, and dehydrated through an ethanol series and two acetone baths. Dehydration includes a 2-hr stop in 75% ethanol containing 2% uranyl acetate. After embedding in Spurr's epoxy resin, specimens are sectioned and poststained in 0.5% aqueous acetate for 6 min and saturated aqueous lead citrate 3--4 min. This technique reduces killing time to less than 2 sec, straightens specimens for easier orientation, and eliminates the typically high internal pressure of nematodes which causes displacement of internal structures observed with other fixation techniques. PMID:1103371

  19. A Pepper MSRB2 Gene Confers Drought Tolerance in Rice through the Protection of Chloroplast-Targeted Genes

    PubMed Central

    Chae, Songhwa; Lee, Tae-Ho; Hwang, Duk-Ju; Oh, Sung-Dug; Park, Jong-Sug; Song, Dae-Geun; Pan, Cheol-Ho; Choi, Doil; Kim, Yul-Ho; Nahm, Baek Hie; Kim, Yeon-Ki

    2014-01-01

    Background The perturbation of the steady state of reactive oxygen species (ROS) due to biotic and abiotic stresses in a plant could lead to protein denaturation through the modification of amino acid residues, including the oxidation of methionine residues. Methionine sulfoxide reductases (MSRs) catalyze the reduction of methionine sulfoxide back to the methionine residue. To assess the role of this enzyme, we generated transgenic rice using a pepper CaMSRB2 gene under the control of the rice Rab21 (responsive to ABA protein 21) promoter with/without a selection marker, the bar gene. Results A drought resistance test on transgenic plants showed that CaMSRB2 confers drought tolerance to rice, as evidenced by less oxidative stress symptoms and a strengthened PSII quantum yield under stress conditions, and increased survival rate and chlorophyll index after the re-watering. The results from immunoblotting using a methionine sulfoxide antibody and nano-LC-MS/MS spectrometry suggest that porphobilinogen deaminase (PBGD), which is involved in chlorophyll synthesis, is a putative target of CaMSRB2. The oxidized methionine content of PBGD expressed in E. coli increased in the presence of H2O2, and the Met-95 and Met-227 residues of PBGD were reduced by CaMSRB2 in the presence of dithiothreitol (DTT). An expression profiling analysis of the overexpression lines also suggested that photosystems are less severely affected by drought stress. Conclusions Our results indicate that CaMSRB2 might play an important functional role in chloroplasts for conferring drought stress tolerance in rice. PMID:24614245

  20. Chemical Inhibition of Kynureninase Reduces Pseudomonas aeruginosa Quorum Sensing and Virulence Factor Expression.

    PubMed

    Kasper, Stephen H; Bonocora, Richard P; Wade, Joseph T; Musah, Rabi Ann; Cady, Nathaniel C

    2016-04-15

    The opportunistic pathogen Pseudomonas aeruginosa utilizes multiple quorum sensing (QS) pathways to coordinate an arsenal of virulence factors. We previously identified several cysteine-based compounds inspired by natural products from the plant Petiveria alliacea which are capable of antagonizing multiple QS circuits as well as reducing P. aeruginosa biofilm formation. To understand the global effects of such compounds on virulence factor production and elucidate their mechanism of action, RNA-seq transcriptomic analysis was performed on P. aeruginosa PAO1 exposed to S-phenyl-l-cysteine sulfoxide, the most potent inhibitor from the prior study. Exposure to this inhibitor down-regulated expression of several QS-regulated virulence operons (e.g., phenazine biosynthesis, type VI secretion systems). Interestingly, many genes that were differentially regulated pertain to the related metabolic pathways that yield precursors of pyochelin, tricarboxylic acid cycle intermediates, phenazines, and Pseudomonas quinolone signal (PQS). Activation of the MexT-regulon was also indicated, including the multidrug efflux pump encoded by mexEF-oprN, which has previously been shown to inhibit QS and pathogenicity. Deeper investigation of the metabolites involved in these systems revealed that S-phenyl-l-cysteine sulfoxide has structural similarity to kynurenine, a precursor of anthranilate, which is critical for P. aeruginosa virulence. By supplementing exogenous anthranilate, the QS-inhibitory effect was reversed. Finally, it was shown that S-phenyl-l-cysteine sulfoxide competitively inhibits P. aeruginosa kynureninase (KynU) activity in vitro and reduces PQS production in vivo. The kynurenine pathway has been implicated in P. aeruginosa QS and virulence factor expression; however, this is the first study to show that targeted inhibition of KynU affects P. aeruginosa gene expression and QS, suggesting a potential antivirulence strategy. PMID:26785289