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Sample records for methylated trivalent arsenic-glutathione

  1. Methylated trivalent arsenicals are potent inhibitors of glucose stimulated insulin secretion by murine pancreatic islets

    Energy Technology Data Exchange (ETDEWEB)

    Douillet, Christelle [Department of Nutrition, Gillings School of Global Public Health, 2302 MHRC, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599-7461 (United States); Currier, Jenna [Curriculum in Toxicology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599-7461 (United States); Saunders, Jesse [Department of Nutrition, Gillings School of Global Public Health, 2302 MHRC, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599-7461 (United States); Bodnar, Wanda M. [Department of Environmental Sciences and Engineering, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599-7431 (United States); Matoušek, Tomáš [Institute of Analytical Chemistry of the ASCR, v.v.i., Veveří 97, 602 00 Brno (Czech Republic); Stýblo, Miroslav, E-mail: styblo@med.unc.edu [Department of Nutrition, Gillings School of Global Public Health, 2302 MHRC, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599-7461 (United States)

    2013-02-15

    Epidemiologic evidence has linked chronic exposure to inorganic arsenic (iAs) with an increased prevalence of diabetes mellitus. Laboratory studies have identified several mechanisms by which iAs can impair glucose homeostasis. We have previously shown that micromolar concentrations of arsenite (iAs{sup III}) or its methylated trivalent metabolites, methylarsonite (MAs{sup III}) and dimethylarsinite (DMAs{sup III}), inhibit the insulin-activated signal transduction pathway, resulting in insulin resistance in adipocytes. Our present study examined effects of the trivalent arsenicals on insulin secretion by intact pancreatic islets isolated from C57BL/6 mice. We found that 48-hour exposures to low subtoxic concentrations of iAs{sup III}, MAs{sup III} or DMAs{sup III} inhibited glucose-stimulated insulin secretion (GSIS), but not basal insulin secretion. MAs{sup III} and DMAs{sup III} were more potent than iAs{sup III} as GSIS inhibitors with estimated IC{sub 50} ≤ 0.1 μM. The exposures had little or no effects on insulin content of the islets or on insulin expression, suggesting that trivalent arsenicals interfere with mechanisms regulating packaging of the insulin transport vesicles or with translocation of these vesicles to the plasma membrane. Notably, the inhibition of GSIS by iAs{sup III}, MAs{sup III} or DMAs{sup III} could be reversed by a 24-hour incubation of the islets in arsenic-free medium. These results suggest that the insulin producing pancreatic β-cells are among the targets for iAs exposure and that the inhibition of GSIS by low concentrations of the methylated metabolites of iAs may be the key mechanism of iAs-induced diabetes. - Highlights: ► Trivalent arsenicals inhibit glucose stimulated insulin secretion by pancreatic islets. ► MAs{sup III} and DMAs{sup III} are more potent inhibitors than arsenite with IC{sub 50} ∼ 0.1 μM. ► The arsenicals have little or no effects on insulin expression in pancreatic islets. ► The inhibition of

  2. Methylated trivalent arsenicals are potent inhibitors of glucose stimulated insulin secretion by murine pancreatic islets

    International Nuclear Information System (INIS)

    Douillet, Christelle; Currier, Jenna; Saunders, Jesse; Bodnar, Wanda M.; Matoušek, Tomáš; Stýblo, Miroslav

    2013-01-01

    Epidemiologic evidence has linked chronic exposure to inorganic arsenic (iAs) with an increased prevalence of diabetes mellitus. Laboratory studies have identified several mechanisms by which iAs can impair glucose homeostasis. We have previously shown that micromolar concentrations of arsenite (iAs III ) or its methylated trivalent metabolites, methylarsonite (MAs III ) and dimethylarsinite (DMAs III ), inhibit the insulin-activated signal transduction pathway, resulting in insulin resistance in adipocytes. Our present study examined effects of the trivalent arsenicals on insulin secretion by intact pancreatic islets isolated from C57BL/6 mice. We found that 48-hour exposures to low subtoxic concentrations of iAs III , MAs III or DMAs III inhibited glucose-stimulated insulin secretion (GSIS), but not basal insulin secretion. MAs III and DMAs III were more potent than iAs III as GSIS inhibitors with estimated IC 50 ≤ 0.1 μM. The exposures had little or no effects on insulin content of the islets or on insulin expression, suggesting that trivalent arsenicals interfere with mechanisms regulating packaging of the insulin transport vesicles or with translocation of these vesicles to the plasma membrane. Notably, the inhibition of GSIS by iAs III , MAs III or DMAs III could be reversed by a 24-hour incubation of the islets in arsenic-free medium. These results suggest that the insulin producing pancreatic β-cells are among the targets for iAs exposure and that the inhibition of GSIS by low concentrations of the methylated metabolites of iAs may be the key mechanism of iAs-induced diabetes. - Highlights: ► Trivalent arsenicals inhibit glucose stimulated insulin secretion by pancreatic islets. ► MAs III and DMAs III are more potent inhibitors than arsenite with IC 50 ∼ 0.1 μM. ► The arsenicals have little or no effects on insulin expression in pancreatic islets. ► The inhibition of insulin secretion by arsenite, MAs III or DMAs III is reversible. ► Thus

  3. A new metabolic pathway of arsenite: arsenic-glutathione complexes are substrates for human arsenic methyltransferase Cyt19

    Energy Technology Data Exchange (ETDEWEB)

    Hayakawa, Toru [National Institute for Environmental Studies, Environmental Health Sciences Division, Ibaraki (Japan); Chiba University, Faculty of Pharmaceutical Sciences, Chiba (Japan); Kobayashi, Yayoi; Cui, Xing; Hirano, Seishiro [National Institute for Environmental Studies, Environmental Health Sciences Division, Ibaraki (Japan)

    2005-04-01

    The metabolism of arsenic is generally accepted to proceed by repetitive reduction and oxidative methylation; the latter is mediated by arsenic methyltransferase (Cyt19). In human urine, the major metabolites of inorganic arsenicals such as arsenite (iAs{sup III}) and arsenate (iAs{sup V}) are monomethylarsonic acid (MMA{sup V}) and dimethylarsinic acid (DMA{sup V}). On the other hand, in rat bile, the major metabolites of iAs{sup III} have been reported to be arsenic-glutathione (As-GSH) complexes. In the present study we investigate whether these As-GSH complexes are substrates for arsenic methyltransferase by using human recombinant Cyt19. Analyses by high-performance liquid chromatography-inductively coupled plasma mass spectrometry suggested that arsenic triglutathione (ATG) was generated nonenzymatically from iAs{sup III} when GSH was present at concentrations 2 mM or higher. Human recombinant Cyt19 catalyzed transfer of a methyl group from S-adenosyl-l-methionine to arsenic and produced monomethyl and dimethyl arsenicals. The methylation of arsenic was catalyzed by Cyt19 only when ATG was present in the reaction mixture. Moreover, monomethylarsonic diglutathione (MADG) was a substrate of Cyt19 for further methylation to dimethylarsinic glutathione (DMAG). On the other hand, monomethylarsonous acid (MMA{sup III}), a hydrolysis product of MADG, was not methylated to dimethyl arsenical by Cyt19. These results suggest that As-GSH complexes such as ATG and MADG were converted by Cyt19 to MADG and DMAG, respectively. Both MADG and DMAG were unstable in solution when the GSH concentration was lower than 1 mM, and were hydrolyzed and oxidized to MMA{sup V} and DMA{sup V}, respectively. Metabolism of iAs{sup III} to methylated arsenicals by Cyt19 was via ATG and MADG rather than by oxidative methylation of iAs{sup III} and MMA{sup III}. (orig.)

  4. Bis(2-ethylhexyl)-N,N-diethylcarbamoylmethyl phosphonate as a synergist in the extraction of trivalent lanthanides by 1-phenyl-3-methyl-4-trifluoroacetyl-pyrazolone-5

    International Nuclear Information System (INIS)

    Luxmi Varma, R.; Sujatha, S.; Reddy, M.L.P.; Prasada Rao, T.; Iyer, C.S.P.; Damodaran, A.D.

    1996-01-01

    Synergism in the extraction of trivalent lanthanides such as Nd. Eu and Lu has been investigated using mixtures of 1-phenyl-3-methyl-4-trifluoroacetyl-pyrazolone-5 (HPMTFP) and bis(2-ethylhexyl)-N,N-diethylcarbamoylmethyl phosphonate (CMP) in chloroform. Lanthanides are found to be extracted from 0.01 mol/dm 3 chloroacetate medium with HPMTFP as Ln(PMTFP) 3 or Ln(PMTFP) 3 . CMP in the absence or presence of CMP, respectively. The equilibrium constants of these synergistic species do not increase monotonically with atomic number but have a maximum at Eu. The addition of a synergist, CMP to the metal chelate system not only enhances the extraction efficiency but also improves the selectivities among these trivalent lanthanides. The IR results indicate that CMP acts as a bidentate ligand in these mixed-ligand systems. (orig.)

  5. Trivalent Y3+ ionic sensor development based on (E)-Methyl-N'-nitrobenzylidene-benzenesulfonohydrazide (MNBBSH) derivatives modified with nafion matrix.

    Science.gov (United States)

    Hussain, Mohammad Musarraf; Rahman, Mohammed M; Arshad, Muhammad Nadeem; Asiri, Abdullah M

    2017-07-19

    (E)-Methyl-N'-nitrobenzylidene-benzenesulfonohydrazide (MNBBSH) compounds were synthesized using a condensation procedure from the derivatives of nitrobenzaldehyde and 4-Methyl-benzenesulfonylhydrazine, which crystallized in ethanol and methanol as well as characterized by FTIR, UV-Vis, 1 H-NMR, and 13 C-NMR. MNBBSH structure was confirmed using a single crystal X-ray diffraction technique and used for the detection of selective yttrium ion (Y 3+ ) by I-V system. A thin layer of MNBBSH was deposited onto a glassy carbon electrode (GCE) with 5% nafion for the sensitive and selective Y 3+ sensor. The modified MNBBSH/GCE sensor is exhibited the better electrochemical performances such as sensitivity, limit of detection (LOD), linear dynamic range (LDR), limit of quantification (LOQ), short response time, and long term storage ability towards the selective metal ion (Y 3+ ). The calibration curve of 2-MNBBSH/GCE sensor was plotted at +1.1 V over a broad range of Y 3+ concentration. Sensitivity, LOD, LDR and LOQ of the fabricated sensor towards Y 3+ were calculated from the calibration curve and found as 1.90 pAμM -1  cm -2 , 10.0 pM, 1.0 nM~1.0 mM and 338.33 mM respectively. The 2-MNBBSH/Nafion/GCE sensor was applied to the selective determination of Y 3+ in spiked samples such as industrial effluent and real water samples from different sources, and found acceptable and reasonable results.

  6. Oxidation and detoxification of trivalent arsenic species

    International Nuclear Information System (INIS)

    Aposhian, H. Vasken; Zakharyan, Robert A.; Avram, Mihaela D.; Kopplin, Michael J.; Wollenberg, Michael L.

    2003-01-01

    Arsenic compounds with a +3 oxidation state are more toxic than analogous compounds with a +5 oxidation state, for example, arsenite versus arsenate, monomethylarsonous acid (MMA III ) versus monomethylarsonic acid (MMA V ), and dimethylarsinous acid (DMA III ) versus dimethylarsinic acid (DMA V ). It is no longer believed that the methylation of arsenite is the beginning of a methylation-mediated detoxication pathway. The oxidation of these +3 compounds to their less toxic +5 analogs by hydrogen peroxide needs investigation and consideration as a potential mechanism for detoxification. Xanthine oxidase uses oxygen to oxidize hypoxanthine to xanthine to uric acid. Hydrogen peroxide and reactive oxygen are also products. The oxidation of +3 arsenicals by the hydrogen peroxide produced in the xanthine oxidase reaction was blocked by catalase or allopurinol but not by scavengers of the hydroxy radical, e.g., mannitol or potassium iodide. Melatonin, the singlet oxygen radical scavenger, did not inhibit the oxidation. The production of H 2 O 2 by xanthine oxidase may be an important route for decreasing the toxicity of trivalent arsenic species by oxidizing them to their less toxic pentavalent analogs. In addition, there are many other reactions that produce hydrogen peroxide in the cell. Although chemists have used hydrogen peroxide for the oxidation of arsenite to arsenate to purify water, we are not aware of any published account of its potential importance in the detoxification of trivalent arsenicals in biological systems. At present, this oxidation of the +3 oxidation state arsenicals is based on evidence from in vitro experiments. In vivo experiments are needed to substantiate the role and importance of H 2 O 2 in arsenic detoxication in mammals

  7. Melting in trivalent metal chlorides

    International Nuclear Information System (INIS)

    Saboungi, M.L.; Price, D.L.; Scamehorn, C.; Tosi, M.P.

    1990-11-01

    We report a neutron diffraction study of the liquid structure of YCl 3 and combine the structural data with macroscopic melting and transport data to contrast the behaviour of this molten salt with those of SrCl 2 , ZnCl 2 and AlCl 3 as prototypes of different melting mechanisms for ionic materials. A novel melting mechanism for trivalent metal chlorides, leading to a loose disordered network of edge-sharing octahedral units in the liquid phase, is thereby established. The various melting behaviours are related to bonding character with the help of Pettifor's phenomenological chemical scale. (author). 25 refs, 4 figs, 3 tabs

  8. THE ROLE OF VALENCE AND METHYLATION STATE ON THE ACTIVITY OF ARSENIC DURING MITOSIS

    Science.gov (United States)

    Trivalent methylated arsenicals are much more potent DNA damaging agents, clastogens, and large deletion mutagens than are their inorganic and pentavalent counterparts. Previously we had noticed that many of the arsenicals induced "c-type" anaphases characteristic of spindle pois...

  9. Luminescent sulfides of monovalent and trivalent cations

    International Nuclear Information System (INIS)

    1975-01-01

    The invention discloses a family of luminescent materials or phosphors having a rhombohedral crystal structure and consisting essentially of a mixed host sulfide of at least one monovalent host cation and at least one trivalent host cation, and containing, for each mole of phosphor, 0.0005 to 0.05 mole of at least one activating cation. The monovalent host cations may be Na, K or Rb and Cs. The trivalent host cations may be Gd, La, Lu, Sc and Y. The activating cations may be one or more of trivalent As, Bi, Ce, Dy, Er, Pr, Sb, Sm, Tb and Tm; divalent Lu, Mn, Pb and Sn; and monovalent Ag, Cu and Tl. The novel phosphors may be used in devices to convert electron-beam, ultraviolet or x-ray energy to light in the visible spectrum. Such energy conversion can be employed for example in fluoroscopic screens, and in viewing screens of cathode-ray tubes and other electron tubes

  10. Inhibition of insulin-dependent glucose uptake by trivalent arsenicals: possible mechanism of arsenic-induced diabetes

    International Nuclear Information System (INIS)

    Walton, Felecia S.; Harmon, Anne W.; Paul, David S.; Drobna, Zuzana; Patel, Yashomati M.; Styblo, Miroslav

    2004-01-01

    Chronic exposures to inorganic arsenic (iAs) have been associated with increased incidence of noninsulin (type-2)-dependent diabetes mellitus. Although mechanisms by which iAs induces diabetes have not been identified, the clinical symptoms of the disease indicate that iAs or its metabolites interfere with insulin-stimulated signal transduction pathway or with critical steps in glucose metabolism. We have examined effects of iAs and methylated arsenicals that contain trivalent or pentavalent arsenic on glucose uptake by 3T3-L1 adipocytes. Treatment with inorganic and methylated pentavalent arsenicals (up to 1 mM) had little or no effect on either basal or insulin-stimulated glucose uptake. In contrast, trivalent arsenicals, arsenite (iAs III ), methylarsine oxide (MAs III O), and iododimethylarsine (DMAs III O) inhibited insulin-stimulated glucose uptake in a concentration-dependent manner. Subtoxic concentrations of iAs III (20 μM), MAs III O (1 μM), or DMAs III I (2 μM) decreased insulin-stimulated glucose uptake by 35-45%. Basal glucose uptake was significantly inhibited only by cytotoxic concentrations of iAs III or MAs III O. Examination of the components of the insulin-stimulated signal transduction pathway showed that all trivalent arsenicals suppressed expression and possibly phosphorylation of protein kinase B (PKB/Akt). The concentration of an insulin-responsive glucose transporter (GLUT4) was significantly lower in the membrane region of 3T3-L1 adipocytes treated with trivalent arsenicals as compared with untreated cells. These results suggest that trivalent arsenicals inhibit insulin-stimulated glucose uptake by interfering with the PKB/Akt-dependent mobilization of GLUT4 transporters in adipocytes. This mechanism may be, in part, responsible for the development of type-2 diabetes in individuals chronically exposed to iAs

  11. Citric complexes of trivalent cerium and berkelium

    International Nuclear Information System (INIS)

    Boulhassa, S.

    1977-01-01

    The extraction by thenoyltrifluoroacetone (TTA) in benzene of trivalent cerium, berkelium and californium, at the indicator scale, hydrolysis and complexation by citric acid of these cations are studied. The radionuclides used were 144 Ce, 249 Bk and 249 Cf respectively γ, β and α emitters. The solvent extraction technique of the elements by TTA in benzene from a perchloric medium at the ionic stength 0.1 was employed. The distribution coefficients D were measured by the γ, β or α radiometry. Cerium and berkelium, which have a comparable redox behavior, show in solution a relatively stable valency IV. Therefore the study by solvent extraction of their trivalent form required the standing up of complete reducing conditions of these elements and their stabilization in solution at the valency III. The thermodynamic data obtained for berkelium and californium contribute to understand the chemistry of these elements and permit to complete the third 'tetrad branch' of 5f elements from Cm 3+ to Es 3+ . This tetrad effect is a manifestation of thermodynamic consequence of the 'nephelauxetic effect'. As for Ce(III), the data confirm the pronounced acid property and may be show no neglected ligand effect for f 1 configuration [fr

  12. Influvac, a trivalent inactivated subunit influenza vaccine.

    Science.gov (United States)

    Zuccotti, Gian Vincenzo; Fabiano, Valentina

    2011-01-01

    Influenza represents a major sanitary and socio-economic burden and vaccination is universally considered the most effective strategy for preventing the disease and its complications. Traditional influenza vaccines have been on the market since the late 1940s, with million of doses administered annually worldwide, and demonstrated a substantial efficacy and safety. The trivalent inactivated subunit vaccine has been available for more than 25 years and has been studied in healthy children, adults and the elderly and in people affected by underlying chronic medical conditions. We describe vaccine technology focusing on subunit vaccine production procedures and mode of action and provide updated information on efficacy and safety available data. A review of efficacy and safety data in healthy subjects and in high risk populations from major sponsor- and investigator-driven studies. The vaccine showed a good immunogenicity and a favorable safety profile in all target groups. In the panorama of actually available influenza vaccines, trivalent inactivated subunit vaccine represents a well-established tool for preventing flu and the associated complications.

  13. Chelation of di- and trivalent iron with some polyaminopolycarboxylic acids

    International Nuclear Information System (INIS)

    Hafez, M.B.; Sharabi, Nahid; Patti, Francois.

    1979-02-01

    The chelation of di- and trivalent iron with some polyaminopolycarboxylic acids was studied. The influence of pH on the formation of the complex was investigated, the molecular ratio and the stability constants were determined [fr

  14. The extraction of some trivalent elements with Aliquat-336

    Energy Technology Data Exchange (ETDEWEB)

    FLandgren, A.; Liljenzin, J.O.; Skalberg, M. [Chalmers Univ. of Technology, Goeteborg (Sweden)

    1995-10-01

    The extraction behaviour of some trivalent elements in the Aliquate-336-1,3-diisopropyl genzene-nitric acid system has been investigated. For most of the elements a maximum in the distribution ratio occur at about 2 molar nitric acid. At 0.20 molar Aliquate-336 lanthanum attained the highest distribution ratio, about 0.05, of all investigated elements. It was found that nitric acid to a large extent influences the distribution ratio of trivalent elements since it competes with metal nitrate complexes for the extractant molecules. A first approach to a model describing the extraction system is derived.

  15. Hexavalent and trivalent chromium in leather: What should be done?

    Science.gov (United States)

    Moretto, Angelo

    2015-11-01

    Trivalent chromium compounds are used for leather tanning, and chromium may be released during use of leather goods. In certain instances, small amounts of hexavalent chromium can be formed and released. Both trivalent and hexavalent chromium can elicit allergic skin reaction in chromium sensitised subjects, the latter being significantly more potent. Induction of sensitisation only occurs after exposure to hexavalent chromium. A minority of subjects are sensitised to chromium, and in a fraction of these subjects allergic skin reaction have been described after wearing leather shoes or, less frequently, other leather goods. The evidence that in all these cases the reaction is related to hexavalent chromium is not always strong. The content of hexavalent chromium in leather is regulated in European Union, but rate of release rather than content is relevant for allergic skin reaction. The role of trivalent chromium appear much less relevant if at all. Modern tanning procedure do not pose significant risk due to either hexavalent or trivalent chromium. Dismissing bad quality and worn-off leather goods is relevant in reducing or eliminating the skin reaction. It should also be pointed out that shoe components or substances other than chromium in leather may cause allergic/irritative skin reactions. Copyright © 2015 Elsevier Inc. All rights reserved.

  16. Advancing the scientific basis of trivalent actinide-lanthanide separations

    International Nuclear Information System (INIS)

    Nash, K.L.

    2013-01-01

    For advanced fuel cycles designed to support transmutation of transplutonium actinides, several options have been demonstrated for process-scale aqueous separations for U, Np, Pu management and for partitioning of trivalent actinides and fission product lanthanides away from other fission products. The more difficult mutual separation of Am/Cm from La-Tb remains the subject of considerable fundamental and applied research. The chemical separations literature teaches that the most productive alternatives to pursue are those based on ligand donor atoms less electronegative than O, specifically N- and S-containing complexants and chloride ion (Cl - ). These 'soft-donor' atoms have exhibited usable selectivity in their bonding interactions with trivalent actinides relative to lanthanides. In this report, selected features of soft donor reagent design, characterization and application development will be discussed. The roles of thiocyanate, aminopoly-carboxylic acids and lactate in separation processes are detailed. (authors)

  17. Study on thermostabilizers for trivalent oral poliomyelitis vaccine

    Directory of Open Access Journals (Sweden)

    M. L. F. Leal

    1990-09-01

    Full Text Available Different formulations of trivalent oral poliomyelitis vaccine were tested, in order to obtain better thermostability, reduce corrosion of machinery and improve production costs. Magnesium chloride, sucrose, arginine and 199-Hank's medium were used in the formulations. The most appropriate formulation was a mixture of MgCl2 and arginine, which was highly thermostable, and had low production costs. The low corrosive formulation was rejected, due to low thermostability on storage.

  18. Investigation of complexing of trivalent lanthanoids in aqueous nitrate solutions

    International Nuclear Information System (INIS)

    Kopyrin, A.A.; Proyaev, V.V.; Edinakova, V.

    1985-01-01

    Complexing of trivalent lanthanoids (Ce, Eu) with nitrate-ions in concentrated solutions of lithium and sodium nitrates has been studied in a wide range of ionic forces (1.0-7.0), using the extractional, densimetric and solubility methods. Nitrate complexes registered by the extraction and solubility methods mainly are of second sphere character. During rare earth extraction from concentrated nitrate solutions in the range of nitrate-ion concentrations <= 5 mol/l second sphere neutral nitrate complexes take part in distribution, at higher values of nitrate-ion concentration formation of intrasphere monoligand complexes of lanthanoids should be taken into account

  19. Methylated trivalent arsenicals are potent inhibitors of glucose stimulated insulin secretion by murine pancreatic islets

    Czech Academy of Sciences Publication Activity Database

    Doulliet, Ch.; Currier, J. M.; Saunders, J.; Bodnar, W. M.; Matoušek, Tomáš; Stýblo, M.

    2013-01-01

    Roč. 267, č. 1 (2013), s. 11-15 ISSN 0041-008X R&D Projects: GA MŠk LH12040 Institutional support: RVO:68081715 Keywords : arsenic speciation * tissue * hydride generation Subject RIV: CB - Analytical Chemistry, Separation Impact factor: 3.630, year: 2013

  20. Methylated trivalent arsenicals are potent inhibitors of glucose stimulated insulin secretion by murine pancreatic islets

    Czech Academy of Sciences Publication Activity Database

    Doulliet, Ch.; Currier, J. M.; Saunders, J.; Bodnar, W. M.; Matoušek, Tomáš; Stýblo, M.

    -, July-28 (2013), PMID: 23261974 ISSN 2328-0166 R&D Projects: GA MŠk LH12040 Institutional support: RVO:68081715 Keywords : arsenic speciation * tissue * hydride generation Subject RIV: CB - Analytical Chemistry, Separation http://biomedfrontiers.org/diabetes-2013-july-28/

  1. Direct analysis and stability of methylated trivalent arsenic metabolites in cells and tissues

    Czech Academy of Sciences Publication Activity Database

    Currier, J. M.; Svoboda, Milan; Matoušek, Tomáš; Dědina, Jiří; Stýblo, M.

    2011-01-01

    Roč. 3, č. 12 (2011), s. 1347-1354 ISSN 1756-5901 R&D Projects: GA ČR GA203/09/1783 Institutional research plan: CEZ:AV0Z40310501 Keywords : arsenic speciation * tissue * hydride generation Subject RIV: CB - Analytical Chemistry, Separation Impact factor: 3.902, year: 2011

  2. Liquid structure and melting of trivalent metal chlorides

    International Nuclear Information System (INIS)

    Tosi, M.P.; Pastore, G.; Saboungi, M.L.; Price, D.L.

    1991-03-01

    Many divalent and trivalent metal ions in stoichiometric liquid mixtures of their halides with alkali halides are fourfold or sixfold coordinated by halogens into relatively long-lived ''complexes''. The stability of these local coordination states and the connectivity that arises between them in the approach to the pure polyvalent metal halide melt determines the character of its short-range and possible intermediate-range order. The available evidence on local coordination in some 140 mixtures has been successfully classified by a structure sorting method based on Pettifor's chemical scale of the elements. Within the general phenomenological frame provided by structure sorting, main attention is given in this work to the liquid structure and melting mechanisms of trivalent metal chlorides. The liquid structure of YCl 3 is first discussed on the basis of neutron diffraction measurements and of calculations within a simple ionic model, and the melting mechanisms of YCl 3 and AlCl 3 , which are structurally isomorphous in the crystalline state, are contrasted. By appeal to macroscopic melting parameters and transport coefficients and to liquid structure data on SbCl 3 , it is proposed that the melting mechanisms of these salts may be classified into three main types in correlation with the character of the chemical bond. (author). 31 refs, 1 fig., 3 tabs

  3. Squeezing clathrate cages to host trivalent rare-earth guests

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Jian [Iowa State Univ., Ames, IA (United States). Department of Chemistry; Ames Lab., Ames, IA (United States); He, Yuping [Sandia National Lab. (SNL-CA), Livermore, CA (United States); Mordvinova, Natalia E. [Laboratoire CRISMAT, ENSICAEN, CNRS UMR (France); Lebedev, Oleg [Laboratoire CRISMAT, ENSICAEN, CNRS UMR (France); Kovnir, Kirill [Iowa State Univ., Ames, IA (United States). Department of Chemistry; Ames Lab., Ames, IA (United States)

    2017-11-01

    Strike difference of the trivalent rare-earth cations from their alkali and alkaline-earth peers is in the presence of localized 4f-electrons and strong spin-orbit coupling. Placing trivalent rare-earth cations inside the fullerene molecules or in between the blocks of itinerant magnetic intermetallics gave rise to plethora of fascinating properties and materials. A long-time missing but hardly desired piece is the semiconducting or metallic compound where rare-earth cations are situated inside the oversized polyhedral cages of three-dimensional framework. In this work we present a synthesis of such compounds, rare-earth containing clathrates Ba8-xRxCu16P30. The unambiguous proofs of their composition and crystal structure were achieved by a combination of synchrotron powder diffraction, time-of-flight neutron powder diffraction, scanning-transmission electron microscopy, and electron energy-loss spectroscopy. Our quantum-mechanical calculations and experimental characterizations show that the incorporation of the rare-earth cations significantly enhances the hole mobility and concentration which results in the drastic increase in the thermoelectric performance.

  4. A review on environmental factors regulating arsenic methylation in humans

    International Nuclear Information System (INIS)

    Tseng, C.-H.

    2009-01-01

    Subjects exposed to arsenic show significant inter-individual variation in urinary patterns of arsenic metabolites but insignificant day-to-day intra-individual variation. The inter-individual variation in arsenic methylation can be partly responsible for the variation in susceptibility to arsenic toxicity. Wide inter-ethnic variation and family correlation in urinary arsenic profile suggest a genetic effect on arsenic metabolism. In this paper the environmental factors affecting arsenic metabolism are reviewed. Methylation capacity might reduce with increasing dosage of arsenic exposure. Furthermore, women, especially at pregnancy, have better methylation capacity than their men counterparts, probably due to the effect of estrogen. Children might have better methylation capacity than adults and age shows inconsistent relevance in adults. Smoking and alcohol consumption might be associated with a poorer methylation capacity. Nutritional status is important in the methylation capacity and folate may facilitate the methylation and excretion of arsenic. Besides, general health conditions and medications might influence the arsenic methylation capacity; and technical problems can cause biased estimates. The consumption of seafood, seaweed, rice and other food with high arsenic contents and the extent of cooking and arsenic-containing water used in food preparation may also interfere with the presentation of the urinary arsenic profile. Future studies are necessary to clarify the effects of the various arsenic metabolites including the trivalent methylated forms on the development of arsenic-induced human diseases with the consideration of the effects of confounding factors and the interactions with other effect modifiers

  5. Accumulation and distribution patterns of trivalent 51Cr in rats

    International Nuclear Information System (INIS)

    Zimakov, I.E.; Sin'kov, V.I.; Zakharova, L.L.

    1986-01-01

    The effect of stable isotope of trivalent chromium on the behaviour of its radioactive isotope 54 Cr in the feed-animal food chain is studied. It is shown that the doses of stable chromium of 5 mg/kg and less practically exert no influence on the regularities of 51 Cr behaviour in the organism animals statistically the reliable effect on the Cr 51 level in separate organs and tissues of animals is noted at the doses of stable isotope carrier of 20 and 40 mg/kg. To establish the stable carrier effect f 1 and f 2 their values have been compared in case of 51 Cr single intake without carrier and with stable isotope carrier in the amount of 50 mg/kg. In the last case for kidneys the Ff 2 value decreased and became 0.04 whereas for the spleen practically remained the same

  6. 'Americium(III)/trivalent lanthanides' separation using organothiophosphinic acids

    International Nuclear Information System (INIS)

    Hill, C.; Madic, C.; Baron, P.; Ozawa, Masaki; Tanaka, Yasumasa.

    1997-01-01

    The present paper describes the extraction of neodymium and other lanthanides by saponified Cyanex 301 acid. The saponification of commercial Cyanex 301 acid favoured the extraction of macro concentrations of neodymium from sodium nitrate aqueous solutions (pH eq ∼ 4). The amount of lanthanide extracted in the organic phase always reached the third of the initial concentration of saponified Cyanex 301 acid, which assumed a cation exchange mechanism to occur during the extraction. No nitrate anion took part in the complex formation. This paper also compares the abilities of purified Cyanex 301, Cyanex 302 and Cyanex 272 acids to extract and separate 241 Am(III) from 152 Eu(III). Very high separation factors S.F. Am/Eu were observed in the case of purified Cyanex 301 acid. Finally some studies are presented herein using tri-n-butylphosphate (TBP) as a synergistic extractant with Cyanex 301 acid to separate actinides from trivalent lanthanide. (author)

  7. Bistable luminescence of trivalent rare-earth ions in crystals

    International Nuclear Information System (INIS)

    Sole, Jose Garcia; Ramirez O, Maria de la; Rodenas, Airan; Jaque, Daniel; Bausa, Luisa; Bettinelli, Marco; Speghini, Adolfo; Cavalli, Enrico; Ivleva, Lioudmila

    2006-01-01

    In this work, we have examined three new bistable systems based on the luminescence of three different crystals activated with trivalent rare earth ions. We have focussed our attention on Yb 3+ ions activators, for which the most relevant results are obtained. The first crystal, Sr 0.6 Ba 0.4 Nb 2 O 6 , is a ferroelectric material with a relatively low phase transition temperature (∼370 K), which provides bistability in the luminescence of Yb 3+ ions due to the thermal hysteresis associated with phase transition. The second crystal, LiNbO 3 , provides an intrinsic bistability in the luminescence of Yb 3+ ions, which is driven by changes in the excitation intensity. In the third crystal, NdPO 4 , a new mechanism of excitation intensity driven bistability is obtained when activated with Yb 3+ ions, due to a interplay between the Nd 3+ ↔Yb 3+ energy transfer and back transfer processes

  8. Behaviour of trivalent actinides and lanthanide elements in chloride solution; Comportement des lanthanides et transuraniens trivalents en milieu chlorhydrique

    Energy Technology Data Exchange (ETDEWEB)

    Marin, B [Commissariat a l' Energie Atomique, Fontenay-aux-Roses (France). Centre d' Etudes Nucleaires

    1969-07-01

    The aim of this work is to compare the complexation in chloride solutions of trivalent lanthanides and actinides. We have first studied the solvatation of these cations without complexation. We found a difference between Am, Cm and Rare Earths (we can separate lanthanides into Light and Heavy Rare Earths). For studying the complexation we choose the technic of electrophoresis on paper after establishing a simple theory of mobilities in complex solutions. The hydrolysis of these cations was studied and compared in chloride solutions. We have then studied the complexation with the Cl{sup -} ligand in some solutions: HCl, NH{sub 4}Cl, CaCl{sub 2}, CeCl{sub 3}, LiCl. We have established that the complexation is the same in dilute HCl solutions but in concentrated solutions the trivalent actinides are more complexed. This difference is sharper in LiCl solutions. We also proposed the different models of complex in these solutions. (author) [French] Le but de ce travail est de comparer les transuraniens et lanthanides trivalents au point de vue de leur complexation en solution chlorhydrique. Nous avons ete amenes tout d'abord a etudier la solvatation de ces cations non complexes. C'est ainsi que nous pouvons constater une difference entre Am, Cm et les lanthanides. Ces derniers pouvant se separer en lanthanides legers et lanthanides lourds. Pour etudier la complexation nous avons utilise l'electrophorese sur papier apres avoir donne une theorie simple des mobilites en milieu complexant. Apres avoir etudie et compare l'hydrolyse de ces divers cations en solution chlorhydrique, nous avons etudie leur complexation avec l'ion Cl{sup -} dans dans divers milieux: HCl, NH{sub 4}Cl, CaCl{sub 2}, CeCl{sub 3}, LiCl. ous avons note qu'en solution HCl les deux series se comportent de la meme facon pour des concentrations faibles en Cl{sup -} mais que les transuraniens se complexent plus fortement dans les solutions concentrees. Cette difference s'accroit encore dans les milieux

  9. Structural investigations of N,N'-substituted malonamide crystal compounds as a basis to support trivalent lanthanide extraction mechanisms

    International Nuclear Information System (INIS)

    Ionova, G.; Madic, C.; Ionov, S.; Hudson, M.J.

    1998-01-01

    The problem of bond energies in the nitrato compounds of trivalent lanthanides, Ln, with malonamides, L, of the type: Ln(NO 3 ) 3 (H 2 O) m L and Ln(NO 3 ) 3 L 2 , (L=CH 2 (OCNR 1 R 2 ) 2 ) is approached through a semi-empirical theory connecting thermodynamic with structural properties (STT). Emphasis is given on the relation between bond energies and solvent extraction of complexes of Ln with L from nitric aqueous solutions. STT is presented and applied to nitrato compounds with R 1 =ethyl, R 2 =ethyl, R 1 =methyl, R 2 =cyclohexyl and R 1 =methyl, R 2 =phenyl. For the first time, the effect of the regular decrease of the bond energies Ln-O(nitrato) and Ln-O(L) with the increase of the volume of L is evidenced. The enthalpies of extraction of Ln by L from low nitric acid concentration are calculated. Finally, rules connecting the distribution coefficients D(Ln) in liquid-liquid extraction of Ln (III) by diamides is formulated. These rules appear as a useful guide to predict D(Ln) variation along the series. (orig.)

  10. Atomistic Simulation of Intrinsic Defects and Trivalent and Tetravalent Ion Doping in Hydroxyapatite

    Directory of Open Access Journals (Sweden)

    Ricardo D. S. Santos

    2014-01-01

    Full Text Available Atomistic simulation techniques have been employed in order to investigate key issues related to intrinsic defects and a variety of dopants from trivalent and tetravalent ions. The most favorable intrinsic defect is determined to be a scheme involving calcium and hydroxyl vacancies. It is found that trivalent ions have an energetic preference for the Ca site, while tetravalent ions can enter P sites. Charge compensation is predicted to occur basically via three schemes. In general, the charge compensation via the formation of calcium vacancies is more favorable. Trivalent dopant ions are more stable than tetravalent dopants.

  11. DNA methylation

    DEFF Research Database (Denmark)

    Williams, Kristine; Christensen, Jesper; Helin, Kristian

    2012-01-01

    DNA methylation is involved in key cellular processes, including X-chromosome inactivation, imprinting and transcriptional silencing of specific genes and repetitive elements. DNA methylation patterns are frequently perturbed in human diseases such as imprinting disorders and cancer. The recent...... discovery that the three members of the TET protein family can convert 5-methylcytosine (5mC) into 5-hydroxymethylcytosine (5hmC) has provided a potential mechanism leading to DNA demethylation. Moreover, the demonstration that TET2 is frequently mutated in haematopoietic tumours suggests that the TET...... proteins are important regulators of cellular identity. Here, we review the current knowledge regarding the function of the TET proteins, and discuss various mechanisms by which they contribute to transcriptional control. We propose that the TET proteins have an important role in regulating DNA methylation...

  12. Trivalent europium speciation in a room-temperature ionic liquid

    International Nuclear Information System (INIS)

    Mekki, S.

    2006-10-01

    Since the nuclear industry is playing an important role in the power production field, a relevant number of problems have been revealed. Indeed, high-level radioactive long-lived nuclear wastes present a real difficulty for nuclear wastes management. Minor actinides, which compose most of these wastes, will be radioactive for several thousands of years. For eventual disposal deep underground, their reprocessing needs to be optimized. The extraction processes used industrially to separate actinides and lanthanides from other metal species characterizing the spent nuclear fuel produce, nevertheless, enormous quantities of contaminated liquid wastes directly issued from the liquid/liquid extraction step. During the last decade, some room-temperature ionic liquid have been studied and integrated into industrial processes. The interest on this class of solvent came out from their 'green' properties (non volatile, non flammable, recyclable, etc...), but also from the variability of their physico-chemical properties (stability, hydrophobicity, viscosity) as a function of the RTIL chemical composition. Indeed, it has been shown that classical chemical industrial processes could be transferred into those media, even more improved, while a certain number of difficulties arising from using traditional solvent can be avoided. In this respect, it could be promising to investigate the ability to use room-temperature ionic liquid into the spent nuclear fuel reprocessing field. The aim of this thesis is to test the ability of the specific ionic liquid bumimTf 2 N to allow trivalent europium extraction. The choice of this metal is based on the chemical analogy with trivalent minor actinides Curium and Americium which are contributing the greatest part of the long-lived high-level radioactive wastes. Handling these elements needs to be very cautious for the safety and radioprotection aspect. Moreover, europium is a very sensitive luminescent probe to its environment even at the

  13. Spectroscopic properties of trivalent Europium in various composites with an eulytin structure. Internship report

    International Nuclear Information System (INIS)

    Raynal, Francoise

    1975-01-01

    Eulytin is a bismuth orthosilicate and eulytin compounds revealed to be interesting matrix materials which can be used as medium gain laser materials. This research report is thus a contribution for a better knowledge of this material. Different eulytin compounds doped with lanthanide ions have been used to study the cationic polyhedron (by using structural probes such as the trivalent Europium in spectroscopy, or the trivalent gadolinium in electronic paramagnetic resonance) and the anionic polyhedron

  14. Titration of individual strains in trivalent live-attenuated influenza vaccine without neutralization.

    Science.gov (United States)

    Sirinonthanawech, Naraporn; Surichan, Somchaiya; Namsai, Aphinya; Puthavathana, Pilaipan; Auewarakul, Prasert; Kongchanagul, Alita

    2016-11-01

    Formulation and quality control of trivalent live-attenuated influenza vaccine requires titration of infectivity of individual strains in the trivalent mix. This is usually performed by selective neutralization of two of the three strains and titration of the un-neutralized strain in cell culture or embryonated eggs. This procedure requires standard sera with high neutralizing titer against each of the three strains. Obtaining standard sera, which can specifically neutralize only the corresponding strain of influenza viruses and is able to completely neutralize high concentration of virus in the vaccine samples, can be a problem for many vaccine manufacturers as vaccine stocks usually have very high viral titers and complete neutralization may not be obtained. Here an alternative approach for titration of individual strain in trivalent vaccine without the selective neutralization is presented. This was done by detecting individual strains with specific antibodies in an end-point titration of a trivalent vaccine in cell culture. Similar titers were observed in monovalent and trivalent vaccines for influenza A H3N2 and influenza B strains, whereas the influenza A H1N1 strain did not grow well in cell culture. Viral interference among the vaccine strains was not observed. Therefore, providing that vaccine strains grow well in cell culture, this assay can reliably determine the potency of individual strains in trivalent live-attenuated influenza vaccines. Copyright © 2016 Elsevier B.V. All rights reserved.

  15. Aluminum and iron doped graphene for adsorption of methylated arsenic pollutants

    Energy Technology Data Exchange (ETDEWEB)

    Cortés-Arriagada, Diego, E-mail: dcarriagada@gmail.com; Toro-Labbé, Alejandro

    2016-11-15

    Graphical abstract: Quantum chemistry calculations show the ability of aluminum and iron doped graphene for the removal of methylated arsenicals in their trivalent and pentavalent states, with adsorption energies on the range of 1.5–4.2 eV, and high stability in a water environment. Display Omitted - Highlights: • Al and Fe-doped graphene serve as superior materials for adsorption of methylated arsenicals, including thioarsenicals. • Pentavalent arsenicals are adsorbed with higher adsorption energies (up to 4.2 eV) than trivalent arsenicals (up to 1.7 eV). • The adsorption strength is determined by the weakening of the interacting σAs−O bond in the pollutant. • The adsorption stability was studied in a water environment and molecular dynamics calculations were performed at 300 K. • Trivalent and petavalent forms are mainly adsorbed at neutral pH in their neutral and anionic forms, respectively. - Abstract: The ability of Al and Fe-doped graphene for the adsorption of trivalent and pentavalent methylated arsenic compounds was studied by quantum chemistry computations. The adsorption of trivalent methylarsenicals is reached with adsorption energies of 1.5–1.7 eV at neutral conditions; while, adsorption of pentavalent methylarsenicals reaches adsorption energies of 3.3–4.2 eV and 1.2–2.4 eV from neutral to low pH conditions, respectively. Moreover, the weakening of the interacting σAs−O bond in the pollutant structure played an important role in the stability of the adsorbent–adsorbate systems, determining the adsorption strength. In addition, the pollutant adsorption appears to be efficient in aqueous environments, with even high stability at ambient temperature; in this regard, it was determined that the trivalent and petavalent forms are mainly adsorbed in their neutral and anionic forms at neutral pH, respectively. Therefore, Al and Fe-doped graphene are considered as potential future materials for the removal of methylated arsenic

  16. Aluminum and iron doped graphene for adsorption of methylated arsenic pollutants

    International Nuclear Information System (INIS)

    Cortés-Arriagada, Diego; Toro-Labbé, Alejandro

    2016-01-01

    Graphical abstract: Quantum chemistry calculations show the ability of aluminum and iron doped graphene for the removal of methylated arsenicals in their trivalent and pentavalent states, with adsorption energies on the range of 1.5–4.2 eV, and high stability in a water environment. Display Omitted - Highlights: • Al and Fe-doped graphene serve as superior materials for adsorption of methylated arsenicals, including thioarsenicals. • Pentavalent arsenicals are adsorbed with higher adsorption energies (up to 4.2 eV) than trivalent arsenicals (up to 1.7 eV). • The adsorption strength is determined by the weakening of the interacting σAs−O bond in the pollutant. • The adsorption stability was studied in a water environment and molecular dynamics calculations were performed at 300 K. • Trivalent and petavalent forms are mainly adsorbed at neutral pH in their neutral and anionic forms, respectively. - Abstract: The ability of Al and Fe-doped graphene for the adsorption of trivalent and pentavalent methylated arsenic compounds was studied by quantum chemistry computations. The adsorption of trivalent methylarsenicals is reached with adsorption energies of 1.5–1.7 eV at neutral conditions; while, adsorption of pentavalent methylarsenicals reaches adsorption energies of 3.3–4.2 eV and 1.2–2.4 eV from neutral to low pH conditions, respectively. Moreover, the weakening of the interacting σAs−O bond in the pollutant structure played an important role in the stability of the adsorbent–adsorbate systems, determining the adsorption strength. In addition, the pollutant adsorption appears to be efficient in aqueous environments, with even high stability at ambient temperature; in this regard, it was determined that the trivalent and petavalent forms are mainly adsorbed in their neutral and anionic forms at neutral pH, respectively. Therefore, Al and Fe-doped graphene are considered as potential future materials for the removal of methylated arsenic

  17. First-Principles Modeling of ThO2 Solid Solutions with Oxides of Trivalent Cations

    Science.gov (United States)

    Alexandrov, Vitaly; Asta, Mark; Gronbech-Jensen, Niels

    2010-03-01

    Solid solutions formed by doping ThO2 with oxides of trivalent cations, such as Y2O3 and La2O3, are suitable for solid electrolyte applications, similar to doped zirconia and ceria. ThO2 has also been gaining much attention as an alternative to UO2 in nuclear energy applications, the aforementioned trivalent cations being important fission products. In both cases the mixing energetics and short-range ordering/clustering are key to understanding structural and transport properties. Using first-principles atomistic calculations, we address intra- and intersublattice interactions for both cation and anion sublattices in ThO2-based fluorite-type solid solutions and compare the results with similar modeling studies for related trivalent-doped zirconia systems.

  18. Chalcogenides formed by trivalent rare earth elements with d-elements

    International Nuclear Information System (INIS)

    Flao, Zh.; Laruehl', P.; Olitro, R.

    1981-01-01

    Data on ternary compounds formed by trivalent rare earth elements with 3d-, 4d- and 5d-elements of the Periodic system is presented. Compounds of 3d-elements both in bivalent and trivalent states are considered. The main attention is paid to the structure of the compounds. Description of a great number of new structural types of compounds is given. In certain cases the structure has not been deciphered and, besides, structural investigations with monocrystals are not numerous. Attention is drawn to the existence of nonstoichiometric compounds. References to the works on investigation of thermal (melting temperature), magnetic, optical and electric properties as well as Moessbauer effect are presented

  19. Theoretical study of trivalent element complexes for the nuclear waste reprocessing; Etude theorique de complexes d'elements f trivalents pour le retraitement des dechets nucleaires

    Energy Technology Data Exchange (ETDEWEB)

    Petit, L

    2007-10-15

    Current energetic and environmental concerns have made the nuclear waste reprocessing to be a major issue in numerous countries. One avenue to treat nuclear spent fuel requires separating selectively trivalent minor actinides An (Am{sup 3+}, Cm{sup 3+}) from lanthanides Ln. In this regard, nitrogen extractants are under study. Their selectivity toward actinides is still unclear, but could be the result of enhanced covalency effects with trivalent minor actinides with respect to lanthanides (III). In this thesis, we have performed DFT calculations (Density Functional Theory) to study covalency effects within the actinide-ligand bond, following three main axes of research: advanced study of the nature of the chemical bonding, spectroscopic characterization of covalency, and preliminary tests of ab initio molecular dynamics for future calculations in solvent. Methods that are not regularly applied to trivalent actinides complexes have been used: topological methods, TDDFT, LDDFT, ab initio molecular dynamics. We have managed to show that the selectivity of the BTP ligand - the most effective An/Ln extractant to date - comes at least for a part from stronger covalency effects within the An-BTP bond with respect to the Ln-BTP bond, which has never been proved before. (author)

  20. Creatinine, diet, micronutrients, and arsenic methylation in West Bengal, India.

    Science.gov (United States)

    Basu, Arin; Mitra, Soma; Chung, Joyce; Guha Mazumder, D N; Ghosh, Nilima; Kalman, David; von Ehrenstein, Ondine S; Steinmaus, Craig; Liaw, Jane; Smith, Allan H

    2011-09-01

    Ingested inorganic arsenic (InAs) is methylated to monomethylated (MMA) and dimethylated metabolites (DMA). Methylation may have an important role in arsenic toxicity, because the monomethylated trivalent metabolite [MMA(III)] is highly toxic. We assessed the relationship of creatinine and nutrition--using dietary intake and blood concentrations of micronutrients--with arsenic metabolism, as reflected in the proportions of InAS, MMA, and DMA in urine, in the first study that incorporated both dietary and micronutrient data. We studied methylation patterns and nutritional factors in 405 persons who were selected from a cross-sectional survey of 7,638 people in an arsenic-exposed population in West Bengal, India. We assessed associations of urine creatinine and nutritional factors (19 dietary intake variables and 16 blood micronutrients) with arsenic metabolites in urine. Urinary creatinine had the strongest relationship with overall arsenic methylation to DMA. Those with the highest urinary creatinine concentrations had 7.2% more arsenic as DMA compared with those with low creatinine (p creatinine concentration was the strongest biological marker of arsenic methylation efficiency, and therefore should not be used to adjust for urine concentration in arsenic studies. The new finding that animal fat intake has a positive relationship with MMA% warrants further assessment in other studies. Increased MMA% was also associated, to a lesser extent, with low serum selenium and folate.

  1. DETERMINATION OF URINARY TRIVALENT ARSENICALS (MMASIII AND DMASIII) IN INDIVIDUALS CHRONICALLY EXPOSED TO ARSENIC

    Science.gov (United States)

    DETERMINATION OF URINARY TRIVALENT ARSENICALS (MMAsIII and DMAsIII) IN INDIVIDUALS CHRONICALLY EXPOSED TO ARSENIC. L. M. Del Razo1, M. Styblo2, W. R. Cullen3, and D.J. Thomas4. 1Toxicology Section, Cinvestav-IPN, Mexico, D.F., 2Univ. North Carolina, Chapel Hill, NC; 3Uni...

  2. Seasonal trivalent inactivated influenza vaccine protects against 1918 Spanish influenza virus in ferrets

    Science.gov (United States)

    The influenza H1N1 pandemic of 1918 was one of the worst medical disasters in human history. Recent studies have demonstrated that the hemagglutinin (HA) protein of the 1918 virus and 2009 H1N1 pandemic virus, the latter now a component of the seasonal trivalent inactivated influenza vaccine (TIV),...

  3. METABOLISM AND TISSUE DOSIMETRY OF PENTAVALENT AND TRIVALENT MONOMETHYLATED ARSENIC AFTER ORAL

    Science.gov (United States)

    METABOLISM AND TISSUE DOSIMETRY OF PENTAVALENT AND TRIVALENT MONOMETHYLATED ARSENIC AFTER ORAL ADMINISTRATION IN MICEM F Hughes1, V Devesa2, B M Adair1, M Styblo2, E M Kenyon1, and D J Thomas1. 1US EPA, ORD, NHEERL, ETD, Research Triangle Park, NC; 2UNC-CH, CEMALB, Chapel Hi...

  4. Cost-effectiveness of quadrivalent versus trivalent influenza vaccine in the United States

    NARCIS (Netherlands)

    de Boer, Pieter; Pitman, R.J.; Macabeo, B.; Chit, A.; Postma, M.J.; Crépey, P.

    2014-01-01

    BACKGROUND: Currently used trivalent influenza vaccines (TIVs) contain two strains of influenza A and one strain of influenza B. However, co-circulation of two distinct B lineages and difficulties in predicting which lineage will predominate in the next season have led to frequent B-strain

  5. Trivalent combination vaccine induces broad heterologous immune responses to norovirus and rotavirus in mice.

    Directory of Open Access Journals (Sweden)

    Kirsi Tamminen

    Full Text Available Rotavirus (RV and norovirus (NoV are the two major causes of viral gastroenteritis (GE in children worldwide. We have developed an injectable vaccine design to prevent infection or GE induced with these enteric viruses. The trivalent combination vaccine consists of NoV capsid (VP1 derived virus-like particles (VLPs of GI-3 and GII-4 representing the two major NoV genogroups and tubular RV recombinant VP6 (rVP6, the most conserved and abundant RV protein. Each component was produced in insect cells by a recombinant baculovirus expression system and combined in vitro. The vaccine components were administered intramuscularly to BALB/c mice either separately or in the trivalent combination. High levels of NoV and RV type specific serum IgGs with high avidity (>50% as well as intestinal IgGs were detected in the immunized mice. Cross-reactive IgG antibodies were also elicited against heterologous NoV VLPs not used for immunization (GII-4 NO, GII-12 and GI-1 VLPs and to different RVs from cell cultures. NoV-specific serum antibodies blocked binding of homologous and heterologous VLPs to the putative receptors, histo-blood group antigens, suggesting broad NoV neutralizing activity of the sera. Mucosal antibodies of mice immunized with the trivalent combination vaccine inhibited RV infection in vitro. In addition, cross-reactive T cell immune responses to NoV and RV-specific antigens were detected. All the responses were sustained for up to six months. No mutual inhibition of the components in the trivalent vaccine combination was observed. In conclusion, the NoV GI and GII VLPs combination induced broader cross-reactive and potentially neutralizing immune responses than either of the VLPs alone. Therefore, trivalent vaccine might induce protective immune responses to the vast majority of circulating NoV and RV genotypes.

  6. A sensitive colorimetric aptasensor based on trivalent peroxidase-mimic DNAzyme and magnetic nanoparticles.

    Science.gov (United States)

    Liu, Shuwen; Xu, Naihan; Tan, Chunyan; Fang, Wei; Tan, Ying; Jiang, Yuyang

    2018-08-14

    In this study, a novel colorimetric aptasensor was prepared by coupling trivalent peroxidase-mimic DNAzyme and magnetic nanoparticles for highly sensitive and selective detection of target proteins. A three G-quadruplex (G4) DNA-hemin complex was employed as the trivalent peroxidase-mimic DNAzyme, in which hemin assisted the G4-DNA to fold into a catalytic conformation and act as an enzyme. The design of the aptasensor includes magnetic nanoparticles (MNPs), complementary DNA (cDNA) modified with biotin, and a label-free single strand DNA (ssDNA) including the aptamer and trivalent peroxidase-mimic DNAzyme. The trivalent DNAzyme, which has the highest catalytic activity among multivalent DNAzymes, catalyzed the H 2 O 2 -mediated oxidation of ABTS. The colorless ABTS was oxidized to produce a blue-green product that can be clearly distinguished by the naked eye. The aptamer and trivalent peroxidase-mimic DNAzyme promote the specificity and sensitivity of this detection method, which can be generalized for other targets by simply replacing the corresponding aptamers. To demonstrate the feasible use of the aptasensor for target detection, a well-known tumor biomarker MUC1 was evaluated as the model target. The limits of detection were determined to be 5.08 and 5.60 nM in a linear range of 50-1000 nM in a buffer solution and 10% serum system, respectively. This colorimetric and label-free aptasensor with excellent sensitivity and strong anti-interference ability has potential application in disease diagnoses, prognosis tracking, and therapeutic evaluation. Copyright © 2018 Elsevier B.V. All rights reserved.

  7. Reorientation of the Methyl Group in MAs(III) is the Rate-Limiting Step in the ArsM As(III) S-Adenosylmethionine Methyltransferase Reaction.

    Science.gov (United States)

    Packianathan, Charles; Li, Jiaojiao; Kandavelu, Palani; Sankaran, Banumathi; Rosen, Barry P

    2018-03-01

    The most common biotransformation of trivalent inorganic arsenic (As(III)) is methylation to mono-, di-, and trimethylated species. Methylation is catalyzed by As(III) S -adenosylmethionine (SAM) methyltransferase (termed ArsM in microbes and AS3MT in animals). Methylarsenite (MAs(III)) is both the product of the first methylation step and the substrate of the second methylation step. When the rate of the overall methylation reaction was determined with As(III) as the substrate, the first methylation step was rapid, whereas the second methylation step was slow. In contrast, when MAs(III) was used as the substrate, the rate of methylation was as fast as the first methylation step when As(III) was used as the substrate. These results indicate that there is a slow conformational change between the first and second methylation steps. The structure of CmArsM from the thermophilic alga Cyanidioschyzon merolae sp. 5508 was determined with bound MAs(III) at 2.27 Å resolution. The methyl group is facing the solvent, as would be expected when MAs(III) is bound as the substrate rather than facing the SAM-binding site, as would be expected for MAs(III) as a product. We propose that the rate-limiting step in arsenic methylation is slow reorientation of the methyl group from the SAM-binding site to the solvent, which is linked to the conformation of the side chain of a conserved residue Tyr70.

  8. Use of MgO doped with a divalent or trivalent metal cation for removing arsenic from water

    Science.gov (United States)

    Moore, Robert C; Holt-Larese, Kathleen C; Bontchev, Ranko

    2013-08-13

    Systems and methods for use of magnesium hydroxide, either directly or through one or more precursors, doped with a divalent or trivalent metal cation, for removing arsenic from drinking water, including water distribution systems. In one embodiment, magnesium hydroxide, Mg(OH).sub.2 (a strong adsorbent for arsenic) doped with a divalent or trivalent metal cation is used to adsorb arsenic. The complex consisting of arsenic adsorbed on Mg(OH).sub.2 doped with a divalent or trivalent metal cation is subsequently removed from the water by conventional means, including filtration, settling, skimming, vortexing, centrifugation, magnetic separation, or other well-known separation systems. In another embodiment, magnesium oxide, MgO, is employed, which reacts with water to form Mg(OH).sub.2. The resulting Mg(OH).sub.2 doped with a divalent or trivalent metal cation, then adsorbs arsenic, as set forth above. The method can also be used to treat human or animal poisoning with arsenic.

  9. Use of MgO doped with a divalent or trivalent metal cation for removing arsenic from water

    Energy Technology Data Exchange (ETDEWEB)

    Moore, Robert C.; Larese, Kathleen Caroline; Bontchev, Ranko Panayotov

    2017-05-30

    Systems and methods for use of magnesium hydroxide, either directly or through one or more precursors, doped with a divalent or trivalent metal cation, for removing arsenic from drinking water, including water distribution systems. In one embodiment, magnesium hydroxide, Mg(OH).sub.2 (a strong adsorbent for arsenic) doped with a divalent or trivalent metal cation is used to adsorb arsenic. The complex consisting of arsenic adsorbed on Mg(OH).sub.2 doped with a divalent or trivalent metal cation is subsequently removed from the water by conventional means, including filtration, settling, skimming, vortexing, centrifugation, magnetic separation, or other well-known separation systems. In another embodiment, magnesium oxide, MgO, is employed, which reacts with water to form Mg(OH).sub.2. The resulting Mg(OH).sub.2 doped with a divalent or trivalent metal cation, then adsorbs arsenic, as set forth above. The method can also be used to treat human or animal poisoning with arsenic.

  10. Trivalent Chromium Process (TCP) as a Sealer for MIL-A-8625F Type II, IIB, and IC Anodic Coatings

    National Research Council Canada - National Science Library

    Matzdorf, Craig; Beck, Erin; Hilgeman, Amy; Prado, Ruben

    2008-01-01

    This report documents evaluations of trivalent chromium compositions (TCP) as sealers for MIL-A-8625F Type II, IIB, and IC anodic coatings conducted from March 2001 through December 2007 by Materials Engineering...

  11. Direct analysis of methylated trivalent arsenicals in mouse liver by hydride generation-cryotrapping- atomic absorption spectrometry

    Czech Academy of Sciences Publication Activity Database

    Currier, J. M.; Svoboda, Milan; de Moraes, D. P.; Matoušek, Tomáš; Dědina, Jiří; Stýblo, M.

    2011-01-01

    Roč. 24, č. 4 (2011), s. 478-480 ISSN 0893-228X R&D Projects: GA ČR GA203/09/1783 Institutional research plan: CEZ:AV0Z40310501 Keywords : arsenic speciation * tissue * hydride generation Subject RIV: CB - Analytical Chemistry, Separation Impact factor: 3.779, year: 2011

  12. 4f and 5f trivalent ions complexation by diamides and uses in solvent extraction

    International Nuclear Information System (INIS)

    Huber, H.

    1984-06-01

    Extractive properties of N,N'-tetraalkylmalonamides were investigated in view to separate the actinides contained in highly radioactive wastes. N,N'-dimethyldioctylmalonamide (DMDOMA) was selected. It extracts trivalent actinide and lanthanide from concentrated nitric acid. Mineral acids extraction was studied, especially HNO 3 extraction. The distribution of HNO 3 can be interpreted by assuming that in the organic phase three main species are present: HNO 3 (DMDOMA) 2 , HNO 3 DMDOMA, (HNO 3 ) 2 DMDOMA. 5f and 4f trivalent ions are extracted according to the mechanism: M 3+ + 3NO 3 - + 4DMDOMA in equilibrium with [M(DMDOMA) 2 (NO 3 ) 3 ].(DMDOMA) 2 . The extraction of important ions like U(VI), Np(V), Pu(IV), Pu(VI), Zr(IV) and Fe(III) was investigated. The results showed that DMDOMA behave line the carbamoylmethylenephosphonates and could be an interesting alternative to these organophosphorus extractants [fr

  13. Adsorption behaviors of trivalent actinides and lanthanides on pyridine resin in lithium chloride aqueous solution

    International Nuclear Information System (INIS)

    Tatsuya Suzuki

    2013-01-01

    The adsorption behaviors of trivalent actinides and lanthanides on pyridine resin in lithium chloride aqueous solution were investigated. The adsorbed amounts of lanthanides and the degree of mutual separation of lanthanides increased with an increase in the concentration of lithium chloride in aqueous solution. The group separation of the trivalent actinides and lanthanides was observed. This separation phenomenon is similar in a hydrochloric acid solution. However, the adsorption behavior of lanthanides in lithium chloride is different from their behavior in a hydrochloric acid solution. This fact shows that the adsorption mechanisms of lanthanides in a lithium chloride aqueous solution and in a hydrochloric acid solution are different; the adsorption mechanisms are attributed to the ion exchange in a hydrochloric acid solution, and to the complex formation with pyridine group in a lithium chloride solution. (author)

  14. Trivalent lanthanide/actinide separation in the spent nuclear fuel wastes' reprocessing

    International Nuclear Information System (INIS)

    Narbutt, J.; Krejzler, J.

    2006-01-01

    Separation of trivalent actinides, in particular americium and curium, from lanthanides is an important step in an advanced partitioning process for future reprocessing of spent nuclear fuels. Since the trivalent actinides and lanthanides have similar chemistries, it is rather difficult to separate them from each other. The aim of presented work was to study solvent extraction of Am(III) and Eu(III) in a system containing diethylhemi-BTP (6-(5,6-diethyl-1,2,4-triazin-3-yl)-2,2'-bipyridine) and COSAN (protonated bis(chlorodicarbollido)cobalt(III)). The system was chosen by several groups working in the integrated EC research Project EUROPART. Several physicochemical properties of the extraction system were analyzed and discussed

  15. Synergistic extraction of trivalent lanthanoids with 3-phenyl-4-benzoyl-5-isoxazolone and various sulphoxides

    International Nuclear Information System (INIS)

    Sahu, S.K.; Chakravortty, V.; Reddy, M.L.P.; Ramamohan, T.R.

    1999-01-01

    Synergistic extraction of trivalent lanthanoids Nd, Tb and Tm with mixtures of 3-phenyl-4-benzoyl-5-isoxazolone (HPBI) and dioctyl sulphoxide (DOSO), bis-2-ethylhexyl sulphoxide (B2EHSO) or diphenyl sulphoxide (DPhSO) in xylene from perchlorate solution was investigated. Lanthanoids were found to be extracted as Ln(PBI) 3 with HPBI alone. In the presence of sulphoxides, Nd(III) was found to be extracted as Nd(PBI) 3 . S and Nd(PBI) 3 . 2 S (where S = sulphoxide). On the other hand, Tb(III) and Tm(III) were extracted as Tb(PBI) 3 . S and Tm(PBI) 3 . S respectively. The equilibrium constants of the synergistic species were found to increase monotonically with decreasing ionic radii of these metal ions. The addition of a sulphoxide to the metal chelate system not only enhances the extraction efficiency but also improves the selectivities among these trivalent lanthanoids. (orig.)

  16. Extraordinary superconductor with nearly trivalent cerium, CeCu2Si2

    International Nuclear Information System (INIS)

    Ishikawa, M.; Jaccard, D.; Jorda, J.-L.

    1982-01-01

    Concentrating on the ternary phase diagram, the authors have performed a complementary investigation on CeCu 2 Si 2 and confirm that the compound containing nearly trivalent cerium ions is a new type of superconductor with Tsub(c) around 0.5 K. The analyses of the upper critical field curve support the description of the compound by heavy fermion quasiparticles. Other particular features of this compound are also presented. (Auth.)

  17. Studies on trivalent lanthanide complexes of bis-vanillin p-phenylenediamine

    International Nuclear Information System (INIS)

    Shahma, Abu; Ahmad, Naseer

    1983-01-01

    The coordination interaction of lanthanide(III) chlorides with bis-vanillin o-phenylenediamine was studied by Ansari and Ahmad (1977). It was thought fruitful to compare these with the complexes of trivalent lanthanide ions with bis-vanillin p-phenylenediamine. The newly synthesized complexes were subjected to elemental, thermogravimetric and differential thermal analyses and their melting points, magnetic susceptibilities, molar conductances determined and infrared and electronic spectra taken. (author)

  18. Geochemical Modeling of Trivalent Chromium Migration in Saline-Sodic Soil during Lasagna Process: Impact on Soil Physicochemical Properties

    Science.gov (United States)

    Bukhari, Alaadin; Al-Malack, Muhammad H.; Mu'azu, Nuhu D.; Essa, Mohammed H.

    2014-01-01

    Trivalent Cr is one of the heavy metals that are difficult to be removed from soil using electrokinetic study because of its geochemical properties. High buffering capacity soil is expected to reduce the mobility of the trivalent Cr and subsequently reduce the remedial efficiency thereby complicating the remediation process. In this study, geochemical modeling and migration of trivalent Cr in saline-sodic soil (high buffering capacity and alkaline) during integrated electrokinetics-adsorption remediation, called the Lasagna process, were investigated. The remedial efficiency of trivalent Cr in addition to the impacts of the Lasagna process on the physicochemical properties of the soil was studied. Box-Behnken design was used to study the interaction effects of voltage gradient, initial contaminant concentration, and polarity reversal rate on the soil pH, electroosmotic volume, soil electrical conductivity, current, and remedial efficiency of trivalent Cr in saline-sodic soil that was artificially spiked with Cr, Cu, Cd, Pb, Hg, phenol, and kerosene. Overall desirability of 0.715 was attained at the following optimal conditions: voltage gradient 0.36 V/cm; polarity reversal rate 17.63 hr; soil pH 10.0. Under these conditions, the expected trivalent Cr remedial efficiency is 64.75 %. PMID:25152905

  19. Linear free energy relationship applied to trivalent cations with lanthanum and actinium oxide and hydroxide structure

    International Nuclear Information System (INIS)

    Ragavan, Anpalaki J.

    2006-01-01

    Linear free energy relationships for trivalent cations with crystalline M 2 O 3 and, M(OH) 3 phases of lanthanides and actinides were developed from known thermodynamic properties of the aqueous trivalent cations, modifying the Sverjensky and Molling equation. The linear free energy relationship for trivalent cations is as ΔG f,MvX 0 =a MvX ΔG n,M 3+ 0 +b MvX +β MvX r M 3+ , where the coefficients a MvX , b MvX , and β MvX characterize a particular structural family of MvX, r M 3+ is the ionic radius of M 3+ cation, ΔG f,MvX 0 is the standard Gibbs free energy of formation of MvX and ΔG n,M 3+ 0 is the standard non-solvation free energy of the cation. The coefficients for the oxide family are: a MvX =0.2705, b MvX =-1984.75 (kJ/mol), and β MvX =197.24 (kJ/molnm). The coefficients for the hydroxide family are: a MvX =0.1587, b MvX =-1474.09 (kJ/mol), and β MvX =791.70 (kJ/molnm).

  20. Extraction characteristics of trivalent lanthanides and actinides in mixtures of dinonylnaphthalenesulfonic acid and carboxylic acids

    International Nuclear Information System (INIS)

    West, M.H.

    1983-03-01

    Dinonylnaphthalenesulfonic acid (HDNNS) has been shown to be an effective liquid cation exchanger for the extraction of metal ions. This extractant has proven to be successful in the extraction of trivalent lanthanides and actinides in the pH range of 2.0 to 3.0, although it shows little selectivity for individual ions because of its strong acid character. In an effort to improve the selectivity of HDNNS between trivalent lanthanides and actinides, carboxylic acids were added to the organic phase and the effects on the extraction characteristics of HDNNS were investigated. Three carboxylic acids - nonanoic, cyclohexanecarboxylic, and cyclohexanebutyric - were studied with the following metals: Am(III), Cm(III), Ce(III), Eu(III), and Tm(III). The distributions of the metal ions were studied holding the HDNNS concentration constant while varying the carboxylic acid concentrations over a range of 1.0 x 10 -5 M to 1.0 M. Results indicated that the greatest enhancement of the extraction occurred at a carboxylic acid concentration of 1.0 x 10 -2 M with negative effects occurring at 0.5 M and 1.0 M. The effects on the extraction of the trivalent lanthanides and actinides were interpreted in terms of the structural differences of the carboxylic acids, the effect of the carboxylic acids on the HDNNS extraction mechanism, and the ionic properties of the metals studied

  1. Complexometric determination of trivalent rare earths and actinides with diethylene-triaminepentaacetic acid

    International Nuclear Information System (INIS)

    Timofeev, G.A.; Simakin, G.A.; Baklanova, P.F.; Kuznetsov, G.F.; Ivanov, V.I.

    1976-01-01

    Optimal conditions have been found for the separate quantitative determination of 200 to 500 mcg of trivalent Eu, La, Nd, Pr, Am and Cm by complexometric titration with diethylenetriaminepentaacetic acid. The final titration point (FTP) has been determined by using one of the following three methods, namely by visual inspection with the aid of xylene orange as an indicator, spectrophotometrically at pH 4.5-4.7 with xylene orange and potentiometrically at pH 4.0-5.5 through the backward titration of the excess complexone with the solution of Fe(3) in HNO 3 . The relative standard errors Ssub(r)=0.004 (Eu), 0.011 Cm with the visual indication of FTP; Ssub(r)=0.005 (Am) with the spectrophotometric indication of FTP; Ssub(r)=0.0O9 (Eu), 0.011 (Pr) and 0.02 (Am) with the potentiometric indication of FTP. Determination of trivalent lanthanides and actinoids is adversely affected by tetravalent actinoids, Zr, U(6), Hg(2) and Fe(3). Titration conditions chosen have been checked in the analysis of the mixture containing the sum of trivalent rare earths, Am and Cm [ru

  2. Spectroscopy and energy level location of the trivalent lanthanides in LiYP4O12

    International Nuclear Information System (INIS)

    Dorenbos, P.; Shalapska, T.; Stryganyuk, G.; Gektin, A.; Voloshinovskii, A.

    2011-01-01

    The excitation and emission properties of the lanthanides Ce 3+ , Pr 3+ , Nd 3+ , Sm 3+ , Eu 3+ , Tb 3+ , Er 3+ , Tm 3+ , and Yb 3+ in LiYP 4 O 12 were studied by vacuum ultra-violet spectroscopy at 10 K. It provides information on the energies of 4f-5d excitation and emission bands. In the case of Er 3+ spin forbidden emission was observed. Charge transfer excitation bands were identified for Eu 3+ , Sm 3+ , Tm 3+ , and Yb 3+ , and in the case of Yb 3+ charge transfer luminescence is observed. All data appear to be consistent with each other and have been used to construct a level scheme showing the location of the energy levels of all trivalent and divalent lanthanides in LiYP 4 O 12 . - Research Highlights: → The spectroscopy of most of the trivalent lanthanides in LiYP 4 O 12 is presented for the first time. → Charge transfer luminescence of Yb3+ is reported. → We demonstrate that the energy of the first 4f-5d transition and the charge transfer band agree with predictive models. → For the first time a scheme with the location of all lanthanide states (divalent and trivalent ) w.r.t. de-valence and conduction band of LIP 4 O 12 is presented.

  3. Dual mechanism of chromatin remodeling in the common shrew sex trivalent (XY 1Y 2

    Directory of Open Access Journals (Sweden)

    Sergey N. Matveevsky

    2017-11-01

    Full Text Available Here we focus on the XY1Y2 condition in male common shrew Sorex araneus Linnaeus, 1758, applying electron microscopy and immunocytochemistry for a comprehensive analysis of structure, synapsis and behaviour of the sex trivalent in pachytene spermatocytes. The pachytene sex trivalent consists of three distinct parts: short and long synaptic SC fragments (between the X and Y1 and between the X and Y2, respectively and a long asynaptic region of the X in-between. Chromatin inactivation was revealed in the XY1 synaptic region, the asynaptic region of the X and a very small asynaptic part of the Y2. This inactive part of the sex trivalent, that we named the ‘head’, forms a typical sex body and is located at the periphery of the meiotic nucleus at mid pachytene. The second part or ‘tail’, a long region of synapsis between the X and Y2 chromosomes, is directed from the periphery into the nucleus. Based on the distribution patterns of four proteins involved in chromatin inactivation, we propose a model of meiotic silencing in shrew sex chromosomes. Thus, we conclude that pachytene sex chromosomes are structurally and functionally two different chromatin domains with specific nuclear topology: the peripheral inactivated ‘true’ sex chromosome regions (part of the X and the Y1 and more centrally located transcriptionally active autosomal segments (part of the X and the Y2.

  4. Theoretical study of trivalent element complexes for the nuclear waste reprocessing

    International Nuclear Information System (INIS)

    Petit, L.

    2007-10-01

    Current energetic and environmental concerns have made the nuclear waste reprocessing to be a major issue in numerous countries. One avenue to treat nuclear spent fuel requires separating selectively trivalent minor actinides An (Am 3+ , Cm 3+ ) from lanthanides Ln. In this regard, nitrogen extractants are under study. Their selectivity toward actinides is still unclear, but could be the result of enhanced covalency effects with trivalent minor actinides with respect to lanthanides (III). In this thesis, we have performed DFT calculations (Density Functional Theory) to study covalency effects within the actinide-ligand bond, following three main axes of research: advanced study of the nature of the chemical bonding, spectroscopic characterization of covalency, and preliminary tests of ab initio molecular dynamics for future calculations in solvent. Methods that are not regularly applied to trivalent actinides complexes have been used: topological methods, TDDFT, LDDFT, ab initio molecular dynamics. We have managed to show that the selectivity of the BTP ligand - the most effective An/Ln extractant to date - comes at least for a part from stronger covalency effects within the An-BTP bond with respect to the Ln-BTP bond, which has never been proved before. (author)

  5. Dissociation dynamics of methylal

    Energy Technology Data Exchange (ETDEWEB)

    Beaud, P; Frey, H -M; Gerber, T; Mischler, B; Radi, P P; Tzannis, A -P [Paul Scherrer Inst. (PSI), Villigen (Switzerland)

    1999-08-01

    The dissociation of methylal is investigated using mass spectrometry, combined with a pyrolytic radical source and femtosecond pump probe experiments. Based on preliminary results two reaction paths of methylal dissociation are proposed and discussed. (author) 4 fig., 3 refs.

  6. Experimental vapor pressures (from 1 Pa to 100 kPa) of six saturated Fatty Acid Methyl Esters (FAMEs): Methyl hexanoate, methyl octanoate, methyl decanoate, methyl dodecanoate, methyl tetradecanoate and methyl hexadecanoate

    International Nuclear Information System (INIS)

    Sahraoui, Lakhdar; Khimeche, Kamel; Dahmani, Abdallah; Mokbel, Ilham; Jose, Jacques

    2016-01-01

    Highlight: • Vapor-liquid equilibria, Enthalpy of Vaporization, saturated Fatty Acid Methyl Ester. - Abstract: Vapor pressures of six saturated Fatty Acid Methyl Esters (FAMEs), methyl hexanoate (or methyl caproate), methyl octanoate (or methyl caprylate), Methyl decanoate (or methyl caprate), methyl dodecanoate (or methyl laurate), methyl tetradecanoate (or methyl myristate), and methyl hexadecanoate (or methyl palmitate) were measured from 1 Pa to 100 kPa and at temperature range between 262 and 453 K using a static apparatus. The experimental data (P-T) were compared with the available literature data.

  7. Methylation of inorganic arsenic in different mammalian species and population groups.

    Science.gov (United States)

    Vahter, M

    1999-01-01

    Thousands of people in different parts of the world are exposed to arsenic via drinking water or contaminated soil or food. The high general toxic of arsenic has been known for centuries, and research during the last decades has shown that arsenic is a potent human carcinogen. However, most experimental cancer studies have failed to demonstrate carcinogenicity in experimental animals, indicating marked variation in sensitivity towards arsenic toxicity between species. It has also been suggested that there is a variation in susceptibility among human individuals. One reason for such variability in toxic response may be variation in metabolism. Inorganic arsenic is methylated in humans as well as animals and micro-organisms, but there are considerable differences between species and individuals. In many, but not all, mammalian species, inorganic arsenic is methylated to methylarsonic acid (MMA) and dimethylarsinic acid (DMA), which are more rapidly excreted in urine than is the inorganic arsenic, especially the trivalent form (AsIII, arsenite) which is highly reactive with tissue components. Absorbed arsenate (AsV) is reduced to trivalent arsenic (AsIII) before the methyl groups are attached. It has been estimated that as much as 50-70% of absorbed AsV is rapidly reduced to AsIII, a reaction which seems to be common for most species. In most experimental animal species, DMA is the main metabolite excreted in urine. Compared to human subjects, very little MMA is produced. However, the rate of methylation varies considerably between species, and several species, e.g. the marmoset monkey and the chimpanzee have been shown not to methylate inorganic arsenic at all. In addition, the marmoset monkey accumulates arsenic in the liver. The rat, on the other hand, has an efficient methylation of arsenic but the formed DMA is to a large extent accumulated in the red blood cells. As a result, the rat shows a low rate of excretion of arsenic. In both human subjects and rodents

  8. Prevalence of antibodies and humoral response after seasonal trivalent vaccination against influenza B lineages in an elderly population of Spain.

    Science.gov (United States)

    Muñoz, Ivan Sanz; Rello, Silvia Rojo; Lejarazu, Raúl Ortiz de

    2017-11-24

    The aim of this study was to analyze the presence of antibodies against both Yamagata and Victoria influenza B lineages and to check the response after seasonal trivalent vaccination. Haemagglutination inhibition assays were performed with pre-and post-vaccination serum samples from 174 individuals ≥65 years of age vaccinated with seasonal trivalent influenza vaccines during the 2006-2007, 2008-2009, 2009-2010 and 2010-2011 vaccine campaigns. 33.9% of individuals showed pre-vaccine protective antibodies (≥1/40) against B/Yamagata lineage and 41.4% against B/Victoria lineage. The annual trivalent vaccine induced significant homologous seroconversion in 14-35.6% of individuals in each vaccine campaign. The population ≥65 years has low-moderate seroprotection against B influenza lineages. Trivalent vaccination induced a slight increase of seroprotection. The trivalent vaccine should be administered to all individuals ≥65 years in all vaccine campaigns. Copyright © 2017 Elsevier España, S.L.U. and Sociedad Española de Enfermedades Infecciosas y Microbiología Clínica. All rights reserved.

  9. Characterization of the sorption behavior of trivalent actinides on zirconium(IV) oxide

    Energy Technology Data Exchange (ETDEWEB)

    Eibl, Manuel; Huittinen, Nina [Helmholtz-Zentrum Dresden-Rossendorf e.V., Dresden (Germany). Surface Processes; Virtanen, S.; Merilaeinen, S.; Lehto, J. [Helsinki Univ. (Finland); Rabung, T. [Karlsruhe Institute of Technology (KIT), Karlsruhe (Germany). Inst. for Nuclear Waste Disposal

    2017-06-01

    The uptake of trivalent Eu and Cm on zirconium(IV) oxide was investigated in batch sorption and TRLFS studies, respectively. Sorption of Eu{sup 3+} was found to start at a pH-value of 4. Based on TRLFS results, sorption of Cm{sup 3+} was assigned to occur through innersphere complex formation at the zirconia surface. A deconvolution of the TRLFS emission spectra gave three different sorption species with strong red-shifts of the peak positions (600.3 nm, 604.3 nm and 608.2 nm) compared to similar systems.

  10. Current strategic thinking for the development of a trivalent alphavirus vaccine for human use.

    Science.gov (United States)

    Wolfe, Daniel N; Heppner, D Gray; Gardner, Shea N; Jaing, Crystal; Dupuy, Lesley C; Schmaljohn, Connie S; Carlton, Kevin

    2014-09-01

    Vaccinations against the encephalitic alphaviruses (western, eastern, and Venezuelan equine encephalitis virus) are of significant interest to biological defense, public health, and agricultural communities alike. Although vaccines licensed for veterinary applications are used in the Western Hemisphere and attenuated or inactivated viruses have been used under Investigational New Drug status to protect at-risk personnel, there are currently no licensed vaccines for use in humans. Here, we will discuss the need for a trivalent vaccine that can protect humans against all three viruses, recent progress to such a vaccine, and a strategy to continue development to Food and Drug Administration licensure. © The American Society of Tropical Medicine and Hygiene.

  11. False-positive result when a diphenylcarbazide spot test is used on trivalent chromium-passivated zinc surfaces

    DEFF Research Database (Denmark)

    Reveko, Valeriia; Lampert, Felix; Din, Rameez Ud

    2018-01-01

    chromium passivation on zinc; however, subsequent analysis by XPS could not confirm the presence of chromium in a hexavalent state. Conclusions Unintended oxidation of DPC induced by atmospheric corrosion is suggested as a possible reason for the false-positive reaction of the DPC test on a trivalent......A colorimetric 1,5-diphenylcarbazide (DPC)-based spot test can be used to identify hexavalent chromium on various metallic and leather surfaces. DPC testing on trivalent chromium-passivated zinc surfaces has unexpectedly given positive results in some cases, apparently indicating the presence...... of hexavalent chromium; however, the presence of hexavalent chromium has never been confirmed with more sensitive and accurate test methods. Objectives To examine the presence of hexavalent chromium on trivalent chromium-passivated zinc surfaces with a DPC-based spot test. Methods A colorimetric DPC spot test...

  12. A trivalent subunit antigen glycoprotein vaccine as immunotherapy for genital herpes in the guinea pig genital infection model.

    Science.gov (United States)

    Awasthi, Sita; Hook, Lauren M; Shaw, Carolyn E; Friedman, Harvey M

    2017-12-02

    An estimated 417 million people worldwide ages 15 to 49 are infected with herpes simplex virus type 2 (HSV-2), the most common cause of genital ulcer disease. Some individuals experience frequent recurrences of genital lesions, while others only have subclinical infection, yet all risk transmitting infection to their intimate partners. A vaccine was developed that prevents shingles, which is a recurrent infection caused by varicella-zoster virus (VZV), a closely related member of the Herpesviridae family. The success of the VZV vaccine has stimulated renewed interest in a therapeutic vaccine for genital herpes. We have been evaluating a trivalent subunit antigen vaccine for prevention of genital herpes. Here, we assess the trivalent vaccine as immunotherapy in guinea pigs that were previously infected intravaginally with HSV-2. The trivalent vaccine contains HSV-2 glycoproteins C, D, and E (gC2, gD2, gE2) subunit antigens administered with CpG and alum as adjuvants. We previously demonstrated that antibodies to gD2 neutralize the virus while antibodies to gC2 and gE2 block their immune evasion activities, including evading complement attack and inhibiting activities mediated by the IgG Fc domain, respectively. Here, we demonstrate that the trivalent vaccine significantly boosts ELISA titers and neutralizing antibody titers. The trivalent vaccine reduces the frequency of recurrent genital lesions and vaginal shedding of HSV-2 DNA by approximately 50% and almost totally eliminates vaginal shedding of replication-competent virus, suggesting that the trivalent vaccine is a worthy candidate for immunotherapy of genital herpes.

  13. Whole-genome methylation caller designed for methyl- DNA ...

    African Journals Online (AJOL)

    etchie

    2013-02-20

    Feb 20, 2013 ... Our method uses a single-CpG-resolution, whole-genome methylation ... Key words: Methyl-DNA immunoprecipitation, next-generation sequencing, ...... methylation is prevalent in embryonic stem cells andmaybe mediated.

  14. Comparison of the Effectiveness of Trivalent Inactivated Influenza Vaccine and Live, Attenuated Influenza Vaccine in Preventing Influenza-Like Illness among US Service Members, 2006-2009

    Science.gov (United States)

    2012-11-26

    controlled studies. Vaccine 2012; 30:886–92. 11. Piedra PA, Gaglani MJ, Kozinetz CA, et al. Trivalent live attenuated intranasal influenza vaccine...120:e553–64. 12. Halloran ME, Piedra PA, Longini IM Jr, et al. Efficacy of trivalent, cold-adapted, influenza virus vaccine against influenza A (Fujian

  15. The Switch From Trivalent to Bivalent Oral Poliovirus Vaccine in the South-East Asia Region.

    Science.gov (United States)

    Bahl, Sunil; Hasman, Andreas; Eltayeb, Abu Obeida; James Noble, Douglas; Thapa, Arun

    2017-07-01

    This analysis describes an innovative and successful approach to risk identification and mitigation in relation to the switch from trivalent to bivalent oral polio vaccine (OPV) in the 11 countries of the World Health Organization's (WHO's) South-East Asia Region (SEAR) in April 2016.The strong commitment of governments and immunization professionals to polio eradication and an exemplary partnership between the WHO, United Nations Children's Fund (UNICEF), and other partners and stakeholders in the region and globally were significant contributors to the success of the OPV switch in the SEAR. Robust national switch plans were developed and country-specific innovations were planned and implemented by the country teams. Close monitoring and tracking of the activities and milestones through dashboards and review meetings were undertaken at the regional level to ensure that implementation time lines were met, barriers identified, and solutions for overcoming challenges were discussed and implemented.The SEAR was the first WHO Region globally to complete the switch and declare the successful withdrawal of trivalent OPV from all countries on 17 May 2016.A number of activities implemented during the switch process are likely to contribute positively to existing immunization practices and to similar initiatives in the future. These activities include better vaccine supply chain management, improved mechanisms for disposal of vaccination-related waste materials, and a closer collaboration with drug regulators, vaccine manufacturers, and the private sector for immunization-related initiatives. © The Author 2017. Published by Oxford University Press for the Infectious Diseases Society of America.

  16. Quantitative analysis of trivalent uranium and lanthanides in a molten chloride by absorption spectrophotometry

    International Nuclear Information System (INIS)

    Toshiyuki Fujii; Akihiro Uehara; Hajimu Yamana

    2013-01-01

    As an analytical application for pyrochemical reprocessing using molten salts, quantitative analysis of uranium and lanthanides by UV/Vis/NIR absorption spectrophotometry was performed. Electronic absorption spectra of LiCl-KCl eutectic at 773 K including trivalent uranium and eight rare earth elements (Y, La, Ce, Pr, Nd, Sm, Eu, and Gd as fission product elements) were measured in the wavenumber region of 4,500-33,000 cm -1 . The composition of the solutes was simulated for a reductive extraction condition in a pyroreprocessing process for spent nuclear fuels, that is, about 2 wt% U and 0.1-2 wt% rare earth elements. Since U(III) possesses strong absorption bands due to f-d transitions, an optical quartz cell with short light path length of 1 mm was adopted in the analysis. The quantitative analysis of trivalent U, Nd, Pr, and Sm was possible with their f-f transition intensities in the NIR region. The analytical results agree with the prepared concentrations within 2σ experimental uncertainties. (author)

  17. New Trident Molecule with Phosphoric Acid Functionality for Trivalent Rare Earth Extraction

    Directory of Open Access Journals (Sweden)

    Keisuke Ohto

    2017-11-01

    Full Text Available Tripodal extraction reagent with three phosphoric acid groups, together with the corresponding monopodal molecule has been prepared to investigate some metals extraction behavior, in particular, trivalent rare earth elements (REEs. The tripodal reagent exhibited extremely high selectivity for metals with high valency such as Zr(IV, In(III, Lu(III, and Fe(III. Tripodal reagent also exhibited exceptionally high extraction ability compared with the corresponding monopodal one in the extraction of trivalent rare earths. The result for the stoichiometry of tripodal reagent to heavy rare earths showed the inflection point between Er (2:1 for a ligand with ion and Tm (1:1. The extraction reactions were determined for all rare earths with both reagents. The extraction equilibrium constants (Kex, the separation factors (β, half pH values (pH1/2, difference half pH values (ΔpH1/2 for extraction of REEs with both reagents are estimated.

  18. Spectroscopic study of trivalent rare earth ions in calcium nitrate hydrate melt

    International Nuclear Information System (INIS)

    Fujii, Toshiyuki; Asano, Hideki; Kimura, Takaumi; Yamamoto, Takeshi; Uehara, Akihiro; Yamana, Hajimu

    2006-01-01

    Influence of the water content to chemical status of trivalent rare earth ions in calcium nitrate hydrate melt was studied by spectroscopic techniques. Fluorescence spectrometry for Eu(III) in Ca(NO 3 ) 2 .RH 2 O and electronic absorption spectrometry for Nd(III) in Ca(NO 3 ) 2 .RH 2 O were performed for analyzing the changing coordination symmetries through the changes in their hypersensitive transitions. Raman spectroscopic study and EXAFS study were performed for Y(NO 3 ) 3 solutions and Y(III) in Ca(NO 3 ) 2 .RH 2 O for analyzing the oxygen bonding to Y(III). Luminescence lifetime study of Eu(III) and Dy(III) in Ca(NO 3 ) 2 .RH 2 O was performed for evaluating the hydration number changes. Results of these spectroscopic studies indicated that, with the decrease of water content (R), the hydration number decreases while the interaction between trivalent rare earth ion and nitrate ion increases. It was also revealed that the symmetry of the coordination sphere gets distorted gradually by this interaction

  19. Biochemical and Hematological Profiles of Common Carp (Cyprinus Carpio under Sublethal Effects of Trivalent Chromium

    Directory of Open Access Journals (Sweden)

    Zeynab Abedi

    2016-07-01

    Full Text Available Background: In natural waters and/or aquaculture facilities, fish are often exposed to chromium waste and demonstrate cumulative deleterious effects. To our knowledge, there are no studies concerning the effects of trivalent Cr on C. carpio hematology. This study presents hematological and some biochemical parameters of common carp, Cyprinus carpio, affected by sublethal concentration of trivalent chromium. Methods: The fish in the experimental aquaria (three replicates each were exposed to a sublethal chromium chloride concentration of 2 mg L−1, which was prepared as stock solution and added depending on the volume of the aquaria to obtain the required concentration. After a period of 28 days, parameters such as hematocrit (Hct, hemoglobin (Hb, lymphocytes (Lym, neutrophils (Neu, total protein (TP, albumin, immunoglobulin M (IgM, glucose, red and white blood cells (RBC and WBC, mean corpuscular volume (MCV, mean corpuscular hemoglobin (MCH, and mean corpuscular hemoglobin concentration (MCHC were examined. Results: Chromium exposure for 28 days significantly (P0.05 between the Cr-exposed fish and the control. Conclusion: Hematological indices of fish, caused by chromium toxicity to C. carpio, can be secondary responses to toxicants, including exposure to low concentrations of heavy metals, which reflect the launch of stress reaction in the affected fish.

  20. Thermal and spectroscopic studies on solid ibuprofen complexes of lighter trivalent lanthanides

    Energy Technology Data Exchange (ETDEWEB)

    Gálico, D.A.; Holanda, B.B.C.; Guerra, R.B.; Legendre, A.O.; Rinaldo, D. [UNESP – Univ Estadual Paulista, Faculdade de Ciências, Departamento de Química, São Paulo CEP 17033-260 (Brazil); Treu-Filho, O. [UNESP – Univ Estadual Paulista, Instituto de Química, São Paulo CEP 14800-900 (Brazil); Bannach, G., E-mail: gilbert@fc.unesp.br [UNESP – Univ Estadual Paulista, Faculdade de Ciências, Departamento de Química, São Paulo CEP 17033-260 (Brazil)

    2014-01-10

    Highlights: • Lighter trivalent lanthanide complexes of ibuprofen have been synthesized. • The TG-FTIR allowed the identification of propane as the gas evolved during the thermal decomposition of the neodymium compound. • The thermal analysis provided information about the composition, dehydration, thermal behavior and thermal decomposition of the samples. • The theoretical and experimental spectroscopic studies suggest that the carboxylate group of ibuprofen is coordinated to the metals by a bidentate bond. - Abstract: Solid-state compounds of general formula Ln(L){sub 3}, in which L is ibuprofen and Ln stands for trivalent La, Ce, Pr, Nd, Sm and Eu, have been synthesized. Simultaneous thermogravimetry and differential thermal analysis (TG-DTA), X-ray powder diffractometry (DRX), complexometry, Fourier-transformed infrared spectroscopy (FTIR) and thermogravimetry coupled to Fourier-transformed infrared spectroscopy (TG-FTIR) were used to characterize these compounds. The results provided information concerning the chemical composition, dehydration, coordination modes of the ligands, crystallinity of the samples, thermal behavior and thermal decomposition of the compounds. The theoretical and experimental spectroscopic studies suggest that ibuprofen coordinates through the carboxylate group as a chelating ligand.

  1. Divalent cation shrinks DNA but inhibits its compaction with trivalent cation.

    Science.gov (United States)

    Tongu, Chika; Kenmotsu, Takahiro; Yoshikawa, Yuko; Zinchenko, Anatoly; Chen, Ning; Yoshikawa, Kenichi

    2016-05-28

    Our observation reveals the effects of divalent and trivalent cations on the higher-order structure of giant DNA (T4 DNA 166 kbp) by fluorescence microscopy. It was found that divalent cations, Mg(2+) and Ca(2+), inhibit DNA compaction induced by a trivalent cation, spermidine (SPD(3+)). On the other hand, in the absence of SPD(3+), divalent cations cause the shrinkage of DNA. As the control experiment, we have confirmed the minimum effect of monovalent cation, Na(+) on the DNA higher-order structure. We interpret the competition between 2+ and 3+ cations in terms of the change in the translational entropy of the counterions. For the compaction with SPD(3+), we consider the increase in translational entropy due to the ion-exchange of the intrinsic monovalent cations condensing on a highly charged polyelectrolyte, double-stranded DNA, by the 3+ cations. In contrast, the presence of 2+ cation decreases the gain of entropy contribution by the ion-exchange between monovalent and 3+ ions.

  2. Microneedle delivery of trivalent influenza vaccine to the skin induces long-term cross-protection.

    Science.gov (United States)

    Kim, Yeu-Chun; Lee, Su-Hwa; Choi, Won-Hyung; Choi, Hyo-Jick; Goo, Tae-Won; Lee, Ju-Hie; Quan, Fu-Shi

    2016-12-01

    A painless self-immunization method with effective and broad cross-protection is urgently needed to prevent infections against newly emerging influenza viruses. In this study, we investigated the cross-protection efficacy of trivalent influenza vaccine containing inactivated A/PR/8/34 (H1N1), A/Hong Kong/68 (H3N2) and B/Lee/40 after skin vaccination using microneedle patches coated with this vaccine. Microneedle vaccination of mice in the skin provided 100% protection against lethal challenges with heterologous pandemic strain influenza A/California/04/09, heterogeneous A/Philippines/2/82 and B/Victoria/287 viruses 8 months after boost immunization. Cross-reactive serum IgG antibody responses against heterologous influenza viruses A/California/04/09, A/Philippines/2/82 and B/Victoria/287 were induced at high levels. Hemagglutination inhibition titers were also maintained at high levels against these heterogeneous viruses. Microneedle vaccination induced substantial levels of cross-reactive IgG antibody responses in the lung and cellular immune responses, as well as cross-reactive antibody-secreting plasma cells in the spleen. Viral loads in the lung were significantly (p skin vaccination with trivalent vaccine using a microneedle array could provide protection against seasonal epidemic or new pandemic strain of influenza viruses.

  3. Labeling of DOTA-conjugated HPMA-based polymers with trivalent metallic radionuclides for molecular imaging.

    Science.gov (United States)

    Eppard, Elisabeth; de la Fuente, Ana; Mohr, Nicole; Allmeroth, Mareli; Zentel, Rudolf; Miederer, Matthias; Pektor, Stefanie; Rösch, Frank

    2018-02-27

    In this work, the in vitro and in vivo stabilities and the pharmacology of HPMA-made homopolymers were studied by means of radiometal-labeled derivatives. Aiming to identify the fewer amount and the optimal DOTA-linker structure that provides quantitative labeling yields, diverse DOTA-linker systems were conjugated in different amounts to HPMA homopolymers to coordinate trivalent radiometals Me(III)* = gallium-68, scandium-44, and lutetium-177. Short linkers and as low as 1.6% DOTA were enough to obtain labeling yields > 90%. Alkoxy linkers generally exhibited lower labeling yields than alkane analogues despite of similar chain length and DOTA incorporation rate. High stability of the radiolabel in all examined solutions was observed for all conjugates. Labeling with scandium-44 allowed for in vivo PET imaging and ex vivo measurements of organ distribution for up to 24 h. This study confirms the principle applicability of DOTA-HPMA conjugates for labeling with different trivalent metallic radionuclides allowing for diagnosis and therapy.

  4. Thermal and spectroscopic studies on solid ibuprofen complexes of lighter trivalent lanthanides

    International Nuclear Information System (INIS)

    Gálico, D.A.; Holanda, B.B.C.; Guerra, R.B.; Legendre, A.O.; Rinaldo, D.; Treu-Filho, O.; Bannach, G.

    2014-01-01

    Highlights: • Lighter trivalent lanthanide complexes of ibuprofen have been synthesized. • The TG-FTIR allowed the identification of propane as the gas evolved during the thermal decomposition of the neodymium compound. • The thermal analysis provided information about the composition, dehydration, thermal behavior and thermal decomposition of the samples. • The theoretical and experimental spectroscopic studies suggest that the carboxylate group of ibuprofen is coordinated to the metals by a bidentate bond. - Abstract: Solid-state compounds of general formula Ln(L) 3 , in which L is ibuprofen and Ln stands for trivalent La, Ce, Pr, Nd, Sm and Eu, have been synthesized. Simultaneous thermogravimetry and differential thermal analysis (TG-DTA), X-ray powder diffractometry (DRX), complexometry, Fourier-transformed infrared spectroscopy (FTIR) and thermogravimetry coupled to Fourier-transformed infrared spectroscopy (TG-FTIR) were used to characterize these compounds. The results provided information concerning the chemical composition, dehydration, coordination modes of the ligands, crystallinity of the samples, thermal behavior and thermal decomposition of the compounds. The theoretical and experimental spectroscopic studies suggest that ibuprofen coordinates through the carboxylate group as a chelating ligand

  5. Methylation pathways in schizophrenia

    International Nuclear Information System (INIS)

    Sargent, T.W. III.

    1982-01-01

    Research on the biochemical causes of human psychosis concentrates on investigating whether schizophremia is linked to abnormalities in the metabolism of methyl carbon groups in the body. The metabolism of C-14 labeled methyl groups in methionine is studied in animals, normal subjects and patient volunteers

  6. Methyl-Analyzer--whole genome DNA methylation profiling.

    Science.gov (United States)

    Xin, Yurong; Ge, Yongchao; Haghighi, Fatemeh G

    2011-08-15

    Methyl-Analyzer is a python package that analyzes genome-wide DNA methylation data produced by the Methyl-MAPS (methylation mapping analysis by paired-end sequencing) method. Methyl-MAPS is an enzymatic-based method that uses both methylation-sensitive and -dependent enzymes covering >80% of CpG dinucleotides within mammalian genomes. It combines enzymatic-based approaches with high-throughput next-generation sequencing technology to provide whole genome DNA methylation profiles. Methyl-Analyzer processes and integrates sequencing reads from methylated and unmethylated compartments and estimates CpG methylation probabilities at single base resolution. Methyl-Analyzer is available at http://github.com/epigenomics/methylmaps. Sample dataset is available for download at http://epigenomicspub.columbia.edu/methylanalyzer_data.html. fgh3@columbia.edu Supplementary data are available at Bioinformatics online.

  7. Trivalent ions modification for high-silica mordenite: A first principles study

    Science.gov (United States)

    Chen, Fayun; Zhang, Laijun; Feng, Gang; Wang, Xuewen; Zhang, Rongbin; Liu, Jianwen

    2018-03-01

    Using periodic DFT-D3-U methods, the present work give a mechanistic insight into the high silica B-, Al-, Ga- and Fe-MOR with H, Li, Na, and K as charge balance ions. The acid properties of the zeolite were probed via NH3 and pyridine adsorption. It is found that the charge balance ions influence the location of the trivalent ions, the cell volumes, as well as the synthesis difficulty of the zeolites. The energy differences for B, Al, Ga and Fe in different T sites are small for the H-form zeolites, while large for the Na- and K-form zeolites. For H-form MOR, the proton of the sbnd OH group prefers to bond to O(7) and O(3) and pointing to the 12MR for trivalent ions in T1 sites. The proton bonds to O(3), O(2), O(2) and O(5), respectively, for B, Al, Ga and Fe in T2 site of MOR, with the sbnd OH group pointing to intersection of 12MR and the side-pocket, except for the B-MOR that sbnd OH group pointing to the 12MR. For trivalent ions located in T3 and T4 sites, the protons prefers to bond to O(1) and O(2), respectively, with the sbnd OH group pointing to the intersection of 8MR and side-pocket as well as the intersection of 12MR and side-pocket. All incorporated B, Al, Ga, and Fe framework ions are tetra-coordinated, except the B atoms are tri-coordinated. The NH4-form MOR has smaller cell volume than the other form MOR. Na and K are energetically more favored charge balance ions than Li and NH3 for MOR zeolites synthesis, and the H-form zeolite is the most difficult to be synthesized directly. The strength of the Brønsted acidity follows the order: HBMOR < HFeMOR ≈ HGaMOR < HAlMOR, vs. the Lewis acidity order: HBMOR < HAlMOR < HFeMOR ≈ HGaMOR. NH3 could be adsorbed inside all kinds of channels, and especially favors in the small 8MR vs. pyridine could only be adsorbed in the main channel of MOR due to the steric effect. It indicates that the acid sites in the side pocket and the small 8-membered ring and the side pocket could not be effectively determined

  8. Fate of trivalent chromium in presence of organic acids - a hydroponic study on soyabean plant using radiotracer

    International Nuclear Information System (INIS)

    Srivastava, Sonal; Prakash, Satya; Srivastava, M.M.

    1999-01-01

    Hydroponic experiments have been conducted to examine the uptake and translocation of root absorbed trivalent chromium in the presence of organic acid supplementation. Statistically significant increase in chromium accumulation in various plant tissues with increasing concentration of organic acids has been observed. Potentiality of organic acids to form labile organically bound Cr III is explored. (author)

  9. Cost-utility of quadrivalent versus trivalent influenza vaccine in Brazil – comparison of outcomes from different static model types

    Directory of Open Access Journals (Sweden)

    Laure-Anne Van Bellinghen

    2018-01-01

    Conclusion: All three models predicted a cost per quality-adjusted life year gained for quadrivalent versus trivalent influenza vaccine in the range of R$19,257 (FLORENCE to R$22,768 (FLORA with the best available data in Brazil (Appendix A.

  10. Shearing and compression behavior of end-grafted polyelectrolyte brushes with mono- and trivalent counterions: a molecular dynamics simulation

    International Nuclear Information System (INIS)

    Cao, Qianqian; Zuo, Chuncheng; Li, Lujuan; He, Hongwei

    2010-01-01

    We investigate polyelectrolytes end-grafted on two apposing walls using molecular dynamics simulation techniques. Monovalent and trivalent counterions are explicitly treated. Under normal compression, the osmotic pressure is examined in detail by decomposing it into various virial terms. It has been found that at small wall separations the increase in the osmotic pressure can be ascribed to the increase in the short-range virial term. At large wall separations, a negative osmotic pressure is observed in trivalent systems. Moreover, we study the effect of lateral shear on the density profiles of monomers and counterions, the net charge distribution, the local pressure tensor, the degree of interpenetration and the friction coefficient. At large shear ratios, the electrostatic interactions are weakened at the interface between two brushes. It is worth noting that although the magnitudes of the normal and shear stress components for the trivalent case are significantly lesser than those for the monovalent case, the friction coefficient is larger in the trivalent systems

  11. The cost-effectiveness of trivalent and quadrivalent influenza vaccination in communities in South Africa, Vietnam and Australia

    NARCIS (Netherlands)

    de Boer, Pieter T; Kelso, Joel K; Halder, Nilimesh; Nguyen, Thi-Phuong-Lan; Moyes, Jocelyn; Cohen, Cheryl; Barr, Ian G; Postma, Maarten J; Milne, George J

    2018-01-01

    BACKGROUND: To inform national healthcare authorities whether quadrivalent influenza vaccines (QIVs) provide better value for money than trivalent influenza vaccines (TIVs), we assessed the cost-effectiveness of TIV and QIV in low-and-middle income communities based in South Africa and Vietnam and

  12. Electrical conductivity of pyroxene which contains trivalent cations: Laboratory measurements and the lunar temperature profile

    International Nuclear Information System (INIS)

    Huebner, J.S.; Duba, A.; Wiggins, L.B.

    1979-01-01

    Three natural orthopyroxene single crystals, measured in the laboratory over the temperature range 850 0 --1200 0 C, are more than 1/2 order of magnitude more electrically conducting than previously measured crystals. Small concentrations (1--2%) of Al 2 O 3 and Cr 2 O 3 present in these crystals may be responsible for their relatively high conductivity. Such pyroxenes, which contain trivalent elements, are more representative of pyroxenes expected to be present in the lunar mantle than those which have been measured by other investigators. The new conductivity values for pyroxene are responsible for a relatively large bulk conductivity calculated for (polymineralic) lunar mantle assemblages. The results permit a somewhat cooler lunar temperature profile than previously proposed. Such lower profiles, several hundred degrees Celsius below the solidus, are quite consistent with low seismic attenuation and deep moonquakes observed in the lunar mantle

  13. Removal of trivalent samarium from aqueous solutions by activated biochar derived from cactus fibres

    Institute of Scientific and Technical Information of China (English)

    Loukia Hadjittofi; Styliana Charalambous; Ioannis Pashalidis

    2016-01-01

    The efficiency of activated biochar fibres obtained fromOpuntia Ficus Indica regarding the sorption of trivalent samarium (Sm(III)) from aqueous solutions was investigated by batch experiments. The effect of various physicochemical parameters (e.g. pH, initial metal concentration, ionic strength, temperature and contact time) on the Sm(III) adsorption was studied and the surface species were characterized by FTIR spectroscopy prior to and after the lanthanide sorption. The experimental results showed that the acti-vated biochar fibres possessed extraordinary sorption capacity for Sm(III) in acidic solutions (qmax=90 g/kg, pH 3.0) and near neutral solutions (qmax=350 g/kg, pH 6.5). This was attributed to the formation of samarium complexes with the surface carboxylic moieties, available in high density on the lamellar structures of the bio-sorbent.

  14. Solvent extraction separations of trivalent lanthanide and actinide ions using an aqueous aminomethanediphosphonic acid

    International Nuclear Information System (INIS)

    Jensen, M. P.

    1998-01-01

    The possibility of separating the trivalent lanthanides, represented by EU 3+ , and actinides, represented by Cf 3+ , using HDEHP in toluene and an aqueous phase containing N-piperidinomethane-1,1-diphosphotic acid, PMDPA, has been investigated. This modified aqueous phase offers potential advantages over the diethylenetriaminepentaacetic acid based TALSPEAK process because of the improved complexation properties of PMDPA in acidic solutions, and the ability to decompose PMDPA before disposal. Extraction experiments were conducted at 25 C in 2 M NaClO 4 between -log [H + ] 1 and 2. The studies enabled us to derive the aqueous phase speciation, the stability constants of the aqueous complexes, and the Cf/Eu separation factors. Despite the presence of an amino group in PMDPA that should favor the retention of the actinides in the aqueous phase, the Cf/Eu separation factors are near unity under the conditions studied

  15. Extraction of trivalent actinides and lanthanides from nitric acid solutions by ion flotation

    International Nuclear Information System (INIS)

    Mezhov, E.H.; Samatov, A.V.; Troyanovskiy, L.V.

    1992-01-01

    To determine whether the deep extraction of trivalent actinides from liquid active waste is feasible, the authors made a detailed investigation into the ion flotation of europium (as a simulator of americium) and americium from nitric acid solutions by using as an SAS precipitant either lauril phosphoric acid (LPA) to reprocess 0.1-0.7 M HNO 3 or diphosphine dioxides (PO) for 1-5 M HNO 3 . In all instances the extent of metal removal increases with floto-reagent expenditure. When the floto-reagent excess required for full precipitation is reached, the extraction of the metals under study is high, viz., 97-98% from 0.1 M HNO 3 with LPA and ∼75% from 3-3.5 M HNO 3 with PO per one flotation operation

  16. Interaction of trivalent actinides and lanthanides with the water/mineral interface

    International Nuclear Information System (INIS)

    Stumpf, Thorsten

    2008-07-01

    The behavior of radionuclides in the natural environment (geo-, hydro- and biosphere) is determined by interface reactions like sorption and incorporation processes. In general natural geochemical systems are very complex. This complexity is a result of a combination of several single reactions on the molecular scale. For the understanding of complex systems and for the prediction of radionuclide behavior in the natural environment it is of cardinal importance to clarify the individual reaction mechanisms at the solid/solution interface. The establishment of clarification requires the application of modern spectroscopic and microscopic methods. The presented studies, which are summarized in this professional dissertation, deal with investigations concerning the interaction of lanthanides and trivalent actinides with mineral surfaces. Several single reactions were deduced from these investigations. In particular the combination of time resolved laser fluorescence spectroscopy (TRLFS) with x-ray absorption spectroscopy (XAS) was proven to be very effective for the elucidation of complex geochemical reactions at the water/mineral interface. (orig.)

  17. Magnesium ionophore II as an extraction agent for trivalent europium and americium

    Energy Technology Data Exchange (ETDEWEB)

    Makrlik, Emanuel [Czech Univ. of Life Sciences, Prague (Czech Republic). Faculty of Environmental Sciences; Vanura, Petr [Univ. of Chemistry and Technology, Prague (Czech Republic). Dept. of Analytical Chemistry

    2016-11-01

    Solvent extraction of microamounts of trivalent europium and americium into nitrobenzene by using a mixture of hydrogen dicarbollylcobaltate (H{sup +}B{sup -}) and magnesium ionophore II (L) was studied. The equilibrium data were explained assuming that the species HL{sup +}, HL{sup +}{sub 2}, ML{sup 3+}{sub 2}, and ML{sup 3+}{sub 3} (M{sup 3+} = Eu{sup 3+}, Am{sup 3+}; L=magnesium, ionophore II) are extracted into the nitrobenzene phase. Extraction and stability constants of the cationic complex species in nitrobenzene saturated with water were determined and discussed. From the experimental results it is evident that this effective magnesium ionophore II receptor for the Eu{sup 3+} and Am{sup 3+} cations could be considered as a potential extraction agent for nuclear waste treatment.

  18. Carbon nanotubes doped with trivalent elements by using back - scattering Raman spectroscopy

    Directory of Open Access Journals (Sweden)

    S. A. Babanejad

    2008-12-01

    Full Text Available  In this paper by using DC arc discharge method and acetylene gas, as the carbon source, and nitrogen, as the carrier gas, canrbon nanotubes, CNTs, doped with trivalent element boron, B, have been produced. The deposited CNTs on the cathod electrod, which have structural doped properties to boron element, have been collected and after purification have been investigated by back-scattering Raman spectroscopy. The results reveal that the high frequency G mode component in CNTs doped with electron acceptor element, B, shift to higher wavenumbers. The low frequency G mode component which can appear at approximately 1540–1570 cm-1 wavenumber region, called BWF mode, is a sign of metallic CNT. In the synthesized doped CNTs due to the presence of boron dopant, D mode has sharp peaks and has relatively high intensity in the Raman spectra .

  19. Binuclear trivalent and tetravalent uranium halides and cyanides supported by cyclooctatetraene ligands

    International Nuclear Information System (INIS)

    Wang, Cong-Zhi; Wu, Qun-Yan; Lan, Jian-Hui; Shi, Wei-Qun; Gibson, John K.

    2017-01-01

    Although the first organoactinide chloride Cp_3UCl (Cp = η"5-C_5H_5) was synthesized more than 50 years ago, binuclear uranium halides remain very rare in organoactinide chemistry. Herein, a series of binuclear trivalent and tetravalent uranium halides and cyanides with cyclooctatetraene ligands, (COT)_2U_2X_n (COT = η"8-C_8H_8; X=F, Cl, CN; n=2, 4), have been systematically studied using scalar-relativistic density functional theory (DFT). The structures with bridging halide or cyanide ligands were predicted to be the most stable complexes of (COT)_2U_2X_n, and all the complexes show weak antiferromagnetic interactions between the uranium centers. However, for each species, there is no significant uranium-uranium bonding interaction. The bonding between the metal and the ligands shows some degree of covalent character, especially between the metal and terminal halide or cyanide ligands. The U-5f and 6d orbitals are predominantly involved in the metal-ligand bonding. All the (COT)_2U_2X_n species were predicted to be more stable compared to the mononuclear half-sandwich complexes at room temperature in the gas phase such that (COT)_2U_2X_4 might be accessible through the known (COT)_2U complex. The tetravalent derivatives (COT)_2U_2X_4 are more energetically favorable than the trivalent (COT)_2U_2X_2 analogs, which may be attributed to the greater number of strong metal-ligand bonds in the former complexes.

  20. Binuclear trivalent and tetravalent uranium halides and cyanides supported by cyclooctatetraene ligands

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Cong-Zhi; Wu, Qun-Yan; Lan, Jian-Hui; Shi, Wei-Qun [Chinese Academy of Sciences, Beijing (China). Laboratory of Nuclear Energy Chemistry and Key Laboratory for Biomedical Effects of Nanomaterials and Nanosafety; Chai, Zhi-Fang [Chinese Academy of Sciences, Beijing (China). Laboratory of Nuclear Energy Chemistry and Key Laboratory for Biomedical Effects of Nanomaterials and Nanosafety; Soochow Univ., Suzhou (China). School of Radiological and Interdisciplinary Sciences (RAD-X); Gibson, John K. [Lawrence Berkeley National Laboratory, CA (United States). Chemical Sciences Division

    2017-03-01

    Although the first organoactinide chloride Cp{sub 3}UCl (Cp = η{sup 5}-C{sub 5}H{sub 5}) was synthesized more than 50 years ago, binuclear uranium halides remain very rare in organoactinide chemistry. Herein, a series of binuclear trivalent and tetravalent uranium halides and cyanides with cyclooctatetraene ligands, (COT){sub 2}U{sub 2}X{sub n} (COT = η{sup 8}-C{sub 8}H{sub 8}; X=F, Cl, CN; n=2, 4), have been systematically studied using scalar-relativistic density functional theory (DFT). The structures with bridging halide or cyanide ligands were predicted to be the most stable complexes of (COT){sub 2}U{sub 2}X{sub n}, and all the complexes show weak antiferromagnetic interactions between the uranium centers. However, for each species, there is no significant uranium-uranium bonding interaction. The bonding between the metal and the ligands shows some degree of covalent character, especially between the metal and terminal halide or cyanide ligands. The U-5f and 6d orbitals are predominantly involved in the metal-ligand bonding. All the (COT){sub 2}U{sub 2}X{sub n} species were predicted to be more stable compared to the mononuclear half-sandwich complexes at room temperature in the gas phase such that (COT){sub 2}U{sub 2}X{sub 4} might be accessible through the known (COT){sub 2}U complex. The tetravalent derivatives (COT){sub 2}U{sub 2}X{sub 4} are more energetically favorable than the trivalent (COT){sub 2}U{sub 2}X{sub 2} analogs, which may be attributed to the greater number of strong metal-ligand bonds in the former complexes.

  1. Influence of a Heterocyclic Nitrogen-Donor Group on the Coordination of Trivalent Actinides and Lanthanides by Aminopolycarboxylate Complexants.

    Science.gov (United States)

    Grimes, Travis S; Heathman, Colt R; Jansone-Popova, Santa; Ivanov, Alexander S; Roy, Santanu; Bryantsev, Vyacheslav S; Zalupski, Peter R

    2018-02-05

    The novel metal chelator N-2-(pyridylmethyl)diethylenetriamine-N,N',N″,N″-tetraacetic acid (DTTA-PyM) was designed to replace a single oxygen-donor acetate group of the well-known aminopolycarboxylate complexant diethylenetriamine-N,N,N',N″,N″-pentaacetic acid (DTPA) with a nitrogen-donor 2-pyridylmethyl. Potentiometric, spectroscopic, computational, and radioisotope distribution methods show distinct differences for the 4f and 5f coordination environments and enhanced actinide binding due to the nitrogen-bearing heterocyclic moiety. The Am 3+ , Cm 3+ , and Ln 3+ complexation studies for DTTA-PyM reveal an enhanced preference, relative to DTPA, for trivalent actinide binding. Fluorescence studies indicate no changes to the octadentate coordination of trivalent curium, while evidence of heptadentate complexation of trivalent europium is found in mixtures containing EuHL (aq) complexes at the same aqueous acidity. The denticity change observed for Eu 3+ suggests that complex protonation occurs on the pyridyl nitrogen. Formation of the CmHL (aq) complex is likely due to the protonation of an available carboxylate group because the carbonyl oxygen can maintain octadentate coordination through a rotation. The observed suppressed protonation of the pyridyl nitrogen in the curium complexes may be attributed to stronger trivalent actinide binding by DTTA-PyM. Density functional theory calculations indicate that added stabilization of the actinide complexes with DTTA-PyM may originate from π-back-bonding interactions between singly occupied 5f orbitals of Am 3+ and the pyridyl nitrogen. The differences between the stabilities of trivalent actinide chelates (Am 3+ , Cm 3+ ) and trivalent lanthanide chelates (La 3+ -Lu 3+ ) are observed in liquid-liquid extraction systems, yielding unprecedented 4f/5f differentiation when using DTTA-PyM as an aqueous holdback reagent. In addition, the enhanced nitrogen-donor softness of the new DTTA-PyM chelator was perturbed by

  2. Influence of a Heterocyclic Nitrogen-Donor Group on the Coordination of Trivalent Actinides and Lanthanides by Aminopolycarboxylate Complexants

    Energy Technology Data Exchange (ETDEWEB)

    Grimes, Travis S. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Heathman, Colt R. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Jansone-Popova, Santa [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Ivanov, Alexander S. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Roy, Santanu [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Bryantsev, Vyacheslav S. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Zalupski, Peter R. [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2018-01-05

    Here, the novel metal chelator N-2-(pyridylmethyl)diethylenetriamine-N,N',N",N"-tetraacetic acid (DTTA-PyM) was designed to replace a single oxygen-donor acetate group of the well-known aminopolycarboxylate complexant diethylenetriamine-N,N,N',N",N"-pentaacetic acid (DTPA) with a nitrogen-donor 2-pyridylmethyl. Potentiometric, spectroscopic, computational, and radioisotope distribution methods show distinct differences for the 4f and 5f coordination environments and enhanced actinide binding due to the nitrogen-bearing heterocyclic moiety. The Am3+, Cm3+, and Ln3+ complexation studies for DTTA-PyM reveal an enhanced preference, relative to DTPA, for trivalent actinide binding. Fluorescence studies indicate no changes to the octadentate coordination of trivalent curium, while evidence of heptadentate complexation of trivalent europium is found in mixtures containing EuHL(aq) complexes at the same aqueous acidity. The denticity change observed for Eu3+ suggests that complex protonation occurs on the pyridyl nitrogen. Formation of the CmHL(aq) complex is likely due to the protonation of an available carboxylate group because the carbonyl oxygen can maintain octadentate coordination through a rotation. The observed suppressed protonation of the pyridyl nitrogen in the curium complexes may be attributed to stronger trivalent actinide binding by DTTA-PyM. Density functional theory calculations indicate that added stabilization of the actinide complexes with DTTA-PyM may originate from π-back-bonding interactions between singly occupied 5f orbitals of Am3+ and the pyridyl nitrogen. The differences between the stabilities of trivalent actinide chelates (Am3+, Cm3+) and trivalent lanthanide chelates (La3+–Lu3+) are observed in liquid–liquid extraction systems, yielding unprecedented 4f/5f differentiation when using DTTA

  3. Identification of Differentially Methylated Sites with Weak Methylation Effects

    Directory of Open Access Journals (Sweden)

    Hong Tran

    2018-02-01

    Full Text Available Deoxyribonucleic acid (DNA methylation is an epigenetic alteration crucial for regulating stress responses. Identifying large-scale DNA methylation at single nucleotide resolution is made possible by whole genome bisulfite sequencing. An essential task following the generation of bisulfite sequencing data is to detect differentially methylated cytosines (DMCs among treatments. Most statistical methods for DMC detection do not consider the dependency of methylation patterns across the genome, thus possibly inflating type I error. Furthermore, small sample sizes and weak methylation effects among different phenotype categories make it difficult for these statistical methods to accurately detect DMCs. To address these issues, the wavelet-based functional mixed model (WFMM was introduced to detect DMCs. To further examine the performance of WFMM in detecting weak differential methylation events, we used both simulated and empirical data and compare WFMM performance to a popular DMC detection tool methylKit. Analyses of simulated data that replicated the effects of the herbicide glyphosate on DNA methylation in Arabidopsis thaliana show that WFMM results in higher sensitivity and specificity in detecting DMCs compared to methylKit, especially when the methylation differences among phenotype groups are small. Moreover, the performance of WFMM is robust with respect to small sample sizes, making it particularly attractive considering the current high costs of bisulfite sequencing. Analysis of empirical Arabidopsis thaliana data under varying glyphosate dosages, and the analysis of monozygotic (MZ twins who have different pain sensitivities—both datasets have weak methylation effects of <1%—show that WFMM can identify more relevant DMCs related to the phenotype of interest than methylKit. Differentially methylated regions (DMRs are genomic regions with different DNA methylation status across biological samples. DMRs and DMCs are essentially the same

  4. DNA methylation in obesity

    Directory of Open Access Journals (Sweden)

    Małgorzata Pokrywka

    2014-11-01

    Full Text Available The number of overweight and obese people is increasing at an alarming rate, especially in the developed and developing countries. Obesity is a major risk factor for diabetes, cardiovascular disease, and cancer, and in consequence for premature death. The development of obesity results from the interplay of both genetic and environmental factors, which include sedentary life style and abnormal eating habits. In the past few years a number of events accompanying obesity, affecting expression of genes which are not directly connected with the DNA base sequence (e.g. epigenetic changes, have been described. Epigenetic processes include DNA methylation, histone modifications such as acetylation, methylation, phosphorylation, ubiquitination, and sumoylation, as well as non-coding micro-RNA (miRNA synthesis. In this review, the known changes in the profile of DNA methylation as a factor affecting obesity and its complications are described.

  5. X-ray absorption and magnetic studies of trivalent lanthanide ions sorbed on pristine and phosphate-modified boehmite surfaces

    International Nuclear Information System (INIS)

    Yoon, Soh-Joung; Helmke, Philip A.; Amonette, James E.; Bleam, William F.

    2002-01-01

    The feasibility of immobilizing radionuclides on mineral surfaces was examined in the absence and the presence of phosphate anions, using trivalent lanthanide ions (Eu3+, Gd3+, and Dy3+) as chemical analogues of trivalent actinide radionuclides. The amount of the lanthanide ions (Ln3+) sorbed on boehmite (gamma-AlOOH) surfaces dramatically increased on the presence of phosphate below pH 5. The structure of the sorbed lanthanide was determined by X-ray absorption spectroscopy, magnetic susceptibility measurements, and electron paramagnetic resonance spectroscopy. We proved Dy3+ forms precipitates on boehmite surfaces in the presence of phosphate, and Gd3+ both in the presence and absence of phosphate. In the presence of phosphate, however, these rare-earth cations react to from ultrafine particles of LnPO4 surface precipitates on boehmite surfaces

  6. Extraction of Trivalent Actinides and Lanthanides from Californium Campaign Rework Solution Using TODGA-based Solvent Extraction System

    Energy Technology Data Exchange (ETDEWEB)

    Benker, Dennis [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Delmau, Laetitia Helene [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Dryman, Joshua Cory [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2017-07-01

    This report presents the studies carried out to demonstrate the possibility of quantitatively extracting trivalent actinides and lanthanides from highly acidic solutions using a neutral ligand-based solvent extraction system. These studies stemmed from the perceived advantage of such systems over cationexchange- based solvent extraction systems that require an extensive feed adjustment to make a low-acid feed. The targeted feed solutions are highly acidic aqueous phases obtained after the dissolution of curium targets during a californium (Cf) campaign. Results obtained with actual Cf campaign solutions, but highly diluted to be manageable in a glove box, are presented, followed by results of tests run in the hot cells with Cf campaign rework solutions. It was demonstrated that a solvent extraction system based on the tetraoctyl diglycolamide molecule is capable of quantitatively extracting trivalent actinides from highly acidic solutions. This system was validated using actual feeds from a Cf campaign.

  7. Selective Separation of Trivalent Actinides from Lanthanides by Aqueous Processing with Introduction of Soft Donor Atoms

    International Nuclear Information System (INIS)

    Nash, Kenneth L.

    2009-01-01

    Implementation of a closed loop nuclear fuel cycle requires the utilization of Pu-containing MOX fuels with the important side effect of increased production of the transplutonium actinides, most importantly isotopes of Am and Cm. Because the presence of these isotopes significantly impacts the long-term radiotoxicity of high level waste, it is important that effective methods for their isolation and/or transmutation be developed. Furthermore, since transmutation is most efficiently done in the absence of lanthanide fission products (high yield species with large thermal neutron absorption cross sections) it is important to have efficient procedures for the mutual separation of Am and Cm from the lanthanides. The chemistries of these elements are nearly identical, differing only in the slightly stronger strength of interaction of trivalent actinides with ligand donor atoms softer than O (N, Cl-, S). Research being conducted around the world has led to the development of new reagents and processes with considerable potential for this task. However, pilot scale testing of these reagents and processes has demonstrated the susceptibility of the new classes of reagents to radiolytic and hydrolytic degradation. In this project, separations of trivalent actinides from fission product lanthanides have been investigated in studies of (1) the extraction and chemical stability properties of a class of soft-donor extractants that are adapted from water-soluble analogs, (2) the application of water soluble soft-donor complexing agents in tandem with conventional extractant molecules emphasizing fundamental studies of the TALSPEAK Process. This research was conducted principally in radiochemistry laboratories at Washington State University. Collaborators at the Radiological Processing Laboratory (RPL) at the Pacific Northwest National Laboratory (PNNL) have contributed their unique facilities and capabilities, and have supported student internships at PNNL to broaden their

  8. A comparative study of the removal of trivalent chromium from aqueous solutions by bentonite and expanded perlite

    International Nuclear Information System (INIS)

    Chakir, Achraf; Bessiere, Jacques; Kacemi, Kacem EL.; Marouf, Bouchaieb

    2002-01-01

    Local bentonite and expanded perlite (Morocco) have been characterised and used for the removal of trivalent chromium from aqueous solutions. The kinetic study had showed that the uptake of Cr(III) by bentonite is very rapid compared to expanded perlite. To calculate the sorption capacities of the two sorbents, at different pH, the experimental data points have been fitted to the Freundlich and Langmuir models, respectively, for bentonite and expanded perlite. For both sorbents the sorption capacity increases with increasing the pH of the suspensions. The removal efficiency has been calculated for both sorbents resulting that bentonite (96% of Cr(III) was removed) is more effective in removing trivalent chromium from aqueous solution than expanded perlite (40% of Cr(III) was removed). In the absence of Cr(III) ions, both bentonite and expanded perlite samples yield negative zeta potential in the pH range of 2-11. The changes of expanded perlite charge, from negative to positive, observed after contact with trivalent chromium(III) solutions was related to Cr(III) sorption on the surface of the solid. Thus, it was concluded that surface complexation plays an important role in the sorption of Cr(III) species on expanded perlite. In the case of bentonite, cation-exchange is the predominate mechanism for sorption of trivalent chromium ions, wherefore no net changes of zeta potential was observed after Cr(III) sorption. X-ray photoelectron spectroscopy measurements, at different pH values, were also made to corroborate the zeta potential results

  9. Complexation of trivalent actinide ions (Am3+, Cm3+) with humic acid: a comparison of different experimental methods

    International Nuclear Information System (INIS)

    Kim, J.I.; Rhee, D.S.; Wimmer, H.; Buckau, G.; Klenze, R.

    1993-01-01

    The complexation of trivalent metal ions with humic acid has been studied at pH 4 and 5 in 0.1 M NaClO 4 by three different experimental methods, i.e. UV spectroscopy, time resolved laser fluorescence spectroscopy (TRLFS) and ultrafiltration. The direct speciation of the metal ion and its humate complex in the reaction process has been made by UV spectroscopy for Am(III) in the micromolar concentration range and by TRLFS for Cm(III) in the nanomolar concentration range. The ultrafiltration is used with the lowest pore size of filter (ca. 1 nm) to separate the uncomplexed metal ion from its complexed species. The concentrations of both metal ion and humic acid are varied in such a manner that the effective functional groups of the humic acid becomes loaded with metal ions from 1% to nearly 100%. The loading capacity of the humic acid for the trivalent metal ion, determined separately at each pH, is introduced into the evaluation of complexation constants. The variation of the metal ion concentration from 6 x 10 -8 mol/l to 4 x 10 -5 mol/l does not show any effect on the complexation reaction. The three different methods give rise to constants being comparable with one another. The average value of the constants thus determined is log β = 6.24±0.28 for the trivalent actinide ions. (orig.)

  10. Investigations of actinides in the context of final disposal of high-level radioactive waste. Trivalent actinides in aqueous solution

    International Nuclear Information System (INIS)

    Banik, N.L.; Boris Brendebach; Marquardt, Ch.M.

    2014-01-01

    The speciation of redox sensitive trivalent actinides Pu(III), Np(III), and U(III) has been studied in aqueous solution. The redox preparation, stabilization, and speciation of these trivalent actinides in aqueous systems are discussed here. The reductants investigated were rongalite, hydroxylamine hydrochloride, and acetohydroxamic acid and the An(III) species have been characterized by UV-Vis and XANES spectroscopy. The results show that the effectiveness of stabilization decreases generally in the order Pu(III) > Np(III) > U(III) and that the effectiveness of each reducing agent depends on the experimental conditions. More than 80 % of Pu(III) aquo species have been stabilized up to pH 5.5, whereas the Np(III) aquo ion could be stabilized in a pH range 0-2.5, and U(III) aquo ion is sufficiently stable at pH 1.0 and below over time periods suitable for experiments. However, this study gives a basis for the characterisation of the trivalent lighter actinides involved in complexation, sorption, and solid formation reactions in the future. (author)

  11. Methylated β-Cyclodextrins

    DEFF Research Database (Denmark)

    Schönbeck, Jens Christian Sidney; Westh, Peter; Madsen, Jens Christian

    2011-01-01

    The complexation of 6 bile salts with various methylated β-cyclodextrins was studied to elucidate how the degree and pattern of substitution affects the binding. The structures of the CDs were determined by mass spectrometry and NMR techniques, and the structures of the inclusion complexes were...

  12. Expected cost effectiveness of high-dose trivalent influenza vaccine in US seniors.

    Science.gov (United States)

    Chit, Ayman; Roiz, Julie; Briquet, Benjamin; Greenberg, David P

    2015-01-29

    Seniors are particularly vulnerable to complications resulting from influenza infection. Numerous influenza vaccines are available to immunize US seniors, and practitioners must decide which product to use. Options include trivalent and quadrivalent standard-dose inactivated influenza vaccines (IIV3 and IIV4 respectively), as well as a high-dose IIV3 (HD). Our research examines the public health impact, budget impact, and cost-utility of HD versus IIV3 and IIV4 for immunization of US seniors 65 years of age and older. Our model was based on US influenza-related health outcome data. Health care costs and vaccine prices were obtained from the Centers for Medicare and Medicaid Services. Efficacies of IIV3 and IIV4 were estimated from various meta-analyses of IIV3 efficacy. The results of a head-to-head randomized controlled trial of HD vs. IIV3 were used to estimate relative efficacy of HD. Conservatively, herd protection was not considered. Compared to IIV3, HD would avert 195,958 cases of influenza, 22,567 influenza-related hospitalizations, and 5423 influenza-related deaths among US seniors. HD generates 29,023 more Quality Adjusted Life Years (QALYs) and a net societal budget impact of $154 million. The Incremental Cost Effectiveness Ratio (ICER) for this comparison is $5299/QALY. 71% of the probabilistic sensitivity analysis (PSA) simulations were seniors. Our conclusions were robust in the face of sensitivity analyses. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.

  13. Bioremoval of trivalent chromium using Bacillus biofilms through continuous flow reactor

    International Nuclear Information System (INIS)

    Sundar, K.; Sadiq, I. Mohammed; Mukherjee, Amitava; Chandrasekaran, N.

    2011-01-01

    Highlights: ► Effective bioremoval of Cr(III) using bacterial biofilms. ► Simplified bioreactor was fabricated for the biofilm development and Cr(III) removal. ► Economically feasible substrate like coarse sand and pebbles were used. - Abstract: Present study deals with the applicability of bacterial biofilms for the bioremoval of trivalent chromium from tannery effluents. A continuous flow reactor was designed for the development of biofilms on different substrates like glass beads, pebbles and coarse sand. The parameters for the continuous flow reactor were 20 ml/min flow rate at 30 °C, pH4. Biofilm biomass on the substrates was in the following sequence: coarse sand > pebbles > glass beads (4.8 × 10 7 , 4.5 × 10 7 and 3.5 × 10 5 CFU/cm 2 ), which was confirmed by CLSM. Biofilms developed using consortium of Bacillus subtilis and Bacillus cereus on coarse sand had more surface area and was able to remove 98% of Cr(III), SEM-EDX proved 92.60% Cr(III) adsorption on biofilms supported by coarse sand. Utilization of Bacillus biofilms for effective bioremoval of Cr(III) from chrome tanning effluent could be a better option for tannery industry, especially during post chrome tanning operation.

  14. Influence of excitation light on the frequency upconversion of trivalent lanthanide ions

    International Nuclear Information System (INIS)

    Fu Zhenxing; Zheng Hairong; Tian Yu; Zhang Zhenglong; Cui Min

    2010-01-01

    The upconversion mechanisms of the 1 D 2 level of Tm 3+ ion under different excitation lights were analyzed. The influences of the excitation lights on the upconversion process, nonradiative relaxation from level 3 F 2 to 3 H 4 and fluorescence properties were investigated. It was shown that the one-color cw excitation could affect the profile of fluorescence, while information of the nonradiative relaxation could not be extracted. The nonradiative relaxation rate measured with the one-color pulsed excitation in crystal phase was in agreement with what was obtained in the free-standing nanometer crystal particles through the two-color pulsed excitation. The characteristics of the fluorescent emissions of Tm 3+ ions doped in various host materials were also discussed under different excitation lights. As a result of the discussion, a possible way to obtain nonradiative relaxation rate directly from a spectroscopic method in frequency domain was proposed. The study can be extended to other trivalent lanthanide ions that have upconversion through excited state absorption.

  15. Peculiarities of extraction of carbonate complexes of trivalent transplutonium elements by alkylpyrocatechins

    International Nuclear Information System (INIS)

    Karalova, Z.K.; Bukina, T.I.; Myasoedov, B.F.; Fedorov, L.A.; Sokolovskij, S.A.

    1987-01-01

    Extraction of trivalent americium, curium, californium and europium by technical mixture of mono- and didecylpyrocatechin (TAP) in various diluents from carbonate solutions is investigated. Effect of many factors (pH, K 2 CO 3 concentration, TAP, metal; the time of phase contact) on the completeness of element isolation and separation is clarified. It is ascertained that the elements listed are quantitatively extracted by TAP solution in toluene and cyclohexane in the range of K 2 CO 3 concentrations from 0.25 to 1.5 mol/l. The difference in americium and curium distribution coefficient during their extraction by TAP from 0.25 mol/l of K 2 CO 3 solution is detected. Separation coefficients of the pair increase with the increase of carbonate solution pH. The separation can be improved at the stage of element reextraction by the mixture of K 2 CO 3 and DTPA or EDTA from alkylpyrocatechin, sunce rate constants of americium and curium reextraction differ greatly. Using 13 C NMR the composition of compounds in organic phase on the basis of 4-(α, α-dioctylethyl)pyrocatechin is investigated

  16. Atomic size effects on local coordination and medium range order in molten trivalent metal chlorides

    International Nuclear Information System (INIS)

    Tatlipinar, H.; Akdeniz, Z.; Pastore, G.

    1992-08-01

    Structural correlations in molten trivalent metal chlorides are evaluated as functions of the metal ion size R M across the range from LaCl 3 (R M approx. 1.4 A) to AlCl 3 (R M approx. 0.8 A), using a charged soft-sphere model and the hypernetted chain approximation. Main attention is given to trends in the local liquid structure (partial radial distribution functions, coordination numbers and bond lengths) and in the intermediate range order (first sharp diffraction peak in the number-number and partial structure factors). The trend towards fourfold local coordination of the metal ions, the stabilization of their first-neighbour chlorine cage and the growth of medium range order are found to proceed in parallel as the size of the metal ion is allowed to decrease at constant number density and temperature. A tendency to molecular-type local structure and liquid-vapour phase separation is found within the hypernetted chain scheme at small metal ion sizes corresponding to AlCl 3 and is emphasized by decreasing the number density of the fluid. The predicted molecular units are rather strongly distorted Al 2 Cl 6 dimers, in agreement with observation. The calculated structural trends for other trichlorides are compared with diffraction and transport data. (author). 17 refs, 8 figs, 1 tab

  17. Factors Affecting the Adsorption of Trivalent Chromium Ions by Activated Carbon Prepared from Waste Rubber Tyres

    Directory of Open Access Journals (Sweden)

    Sylvia E. Benjamin

    2017-08-01

    Full Text Available Economic gains are generally the outcome of industrialization and consequently urbanization. However, positive fiscal index generates a negative impact on natural environment sources heaving pollutant burden on soil, air and water. Industries throw tones of contaminated water into soil and water bodies without proper treatment and create a potential threat for both living and non-living species. Chromium in trivalent state (Cr3+ is added in water bodies and soil through waste water from tanneries, cooling water systems, chemical and pulp and paper industries. The present research work aims at the preparation of an inexpensive activated carbon prepared from non- degradable waste scrap rubber tyres. The carbon produced from scrap rubber tyres was activated by 5% solution of BaCl2 and 0.4 N solution of HCl and verified by ethylene blue solution. The adsorption capacity of the Tyre activated carbon (TAC was investigated for different parameters i.e., initial chromium (III ion concentration, activated carbon dosage, contact/ stirring time and pH. The adsorption capacity of TAC depends on the initial metal ion concentration and the TAC dose. pH of the chromium solution effects the adsorption capacity of TAC due to the formation of tetra hydroxochromate(III complexes,. The results show that TAC offers a cost effective reclamation process for the removal of Cr3+ from effluent waters.

  18. Extraction of trivalent lanthanides and actinides by a synergistic mixture of thenoyltrifluoroacetone and a linear polyether

    International Nuclear Information System (INIS)

    Ensor, D.D.; Shah, A.H.

    1984-01-01

    Mixtures of a two component system, a linear polyether, 1,13-bis[8-quinolyl]-1,4,7,10,13-pentaoxatridecane, K-5, and thenoyltrifluoroacetone, HTTA, have been shown to exhibit synergistic character in the extraction of trivalent lanthanides and actinides. The effect of the addition of K-5 to the organic phase on the extractions of Ce(III), Eu(III), Tm(III), Am(III), Cm(III), Bk(III), and Cf(III) by HTTA in chloroform from 0.5M NaNO 3 at 25 0 C has been measured. These results indicate the extraction is enhanced by the formation of M(TTA) 3 K-5 adduct in the organic phase. The organic phase stability constants for the formation of these synergistic species have been calculated for all the metals studied. The magnitude of these organic phase stability constants for K-5 are similar to other common neutral donors. The order of stability does not follow the normal trend based on charge-to-radius ratio, but follows a pattern based on size, with Am(III) being the most stable

  19. Diglycolamide based dendrimers for sequestration of trivalent actinides: solvent extraction and liquid membrane studies

    International Nuclear Information System (INIS)

    Ansari, S.A.; Mohapatra, P.K.; Leoncini, A.; Verboom, W.

    2017-01-01

    Three diglycolamide-functionalized (poly(propylene imine)) diaminobutane dendrimers, viz. zero generation (L_I), first generation (L_I_I), and second generation (L_I_I_I), were synthesized and evaluated for their extraction ability towards trivalent actinides. The distribution ratio (D) of Am"3"+ with 1.0 mmol/L ligand at 3 M HNO_3 followed the order: 0.1 (L_I) < 42 (L_I_I) < 110 (L_I_I_I). The D values of Am(_I_I_I) at lower acidity (0.01 M HNO_3) were significantly low, giving good stripping option with the dilute acid solution. Extraction of other metal ions from 3 M HNO_3 indicated good selectivity of Am(III) over U(VI), Sr(II) and Cs(I). Supported liquid membrane (SLM) studies were explored for the transport of Am(III) from acidic feed solution, where ligand inventory is extremely low. (author)

  20. Immunogenicity, safety and tolerability of inactivated trivalent influenza vaccine in overweight and obese children.

    Science.gov (United States)

    Esposito, Susanna; Giavoli, Claudia; Trombetta, Claudia; Bianchini, Sonia; Montinaro, Valentina; Spada, Anna; Montomoli, Emanuele; Principi, Nicola

    2016-01-02

    Obesity may be a risk factor for increased hospitalization and deaths from infections due to respiratory pathogens. Additionally, obese patients appear to have impaired immunity after some vaccinations. To evaluate the immunogenicity, safety and tolerability of an inactivated trivalent influenza vaccine (TIV) in overweight and obese children, 28 overweight/obese pediatric patients and 23 healthy normal weight controls aged 3-14 years received a dose of TIV. Four weeks after vaccine administration, significantly higher seroprotection rates against the A/H1N1 strain were observed among overweight/obese children compared with normal weight controls (pvaccination, similar or slightly higher seroconversion and seroprotection rates against the A/H1N1 and A/H3N2 strains were detected in overweight/obese than in normal weight children, whereas significantly higher rates of seroconversion and seroprotection against the B strain were found in overweight/obese patients than in normal weight controls (pvaccine administration (pchildren, antibody response to TIV administration is similar or slightly higher than that evidenced in normal weight subjects of similar age and this situation persists for at least 4 months after vaccine administration in the presence of a favorable safety profile. Copyright © 2015 Elsevier Ltd. All rights reserved.

  1. Inversion of membrane surface charge by trivalent cations probed with a cation-selective channel.

    Science.gov (United States)

    Gurnev, Philip A; Bezrukov, Sergey M

    2012-11-13

    We demonstrate that the cation-selective channel formed by gramicidin A can be used as a reliable sensor for studying the multivalent ion accumulation at the surfaces of charged lipid membranes and the "charge inversion" phenomenon. In asymmetrically charged membranes with the individual leaflets formed from pure negative and positive lipids bathed by 0.1 M CsCl solutions the channel exhibits current rectification, which is comparable to that of a typical n/p semiconductor diode. We show that even at these highly asymmetrical conditions the channel conductance can be satisfactorily described by the electrodiffusion equation in the constant field approximation but, due to predictable limitations, only when the applied voltages do not exceed 50 mV. Analysis of the changes in the voltage-dependent channel conductance upon addition of trivalent cations allows us to gauge their interactions with the membrane surface. The inversion of the sign of the effective surface charge takes place at the concentrations, which correlate with the cation size. Specifically, these concentrations are close to 0.05 mM for lanthanum, 0.25 mM for hexaamminecobalt, and 4 mM for spermidine.

  2. Construction of a trivalent candidate vaccine against Shigella species with DNA recombination

    Institute of Scientific and Technical Information of China (English)

    王恒樑; 冯尔玲; 林云; 廖翔; 金明; 黄留玉; 苏国富; 黄翠芬

    2002-01-01

    In this work asd gene of Shigella flexneri 2a strain T32 was replaced by Vibrio cholerae toxin B subunit (ctxB) gene with DNA recombination in vivo and in vitro. The resulting derivative of T32, designed as FWL01, could stably express CtxB, but its growth in LB medium depended on the presence of diaminopimelic acid (DAP). Then form I plasmid of Shigella sonnei strain S7 was labeled with strain T32 asd gene and mobilized into FWL01. Thus a trivalent candidate oral vaccine strain, designed as FSW01, was constructed. In this candidate strain, a balanced-lethal system was constituted between the host strain and the form I plasmid expressing S. sonnei O antigen. Therefore the candidate strain can express stably not only its own O antigen but also CtxB and O antigen of S. sonnei in the absence of any antibiotic. Experiments showed that FSW01 did not invade HeLa cells or cause keratoconjunctivitis in guinea pigs. However, rabbits immunized FSW01 can elicit significant immune responses. In mice and rhesus monkey models, vaccinated animals were protected against the challenges of wild S. flexneri 2a strain 2457T and S. sonnei strain S9.

  3. Bioremoval of trivalent chromium using Bacillus biofilms through continuous flow reactor

    Energy Technology Data Exchange (ETDEWEB)

    Sundar, K.; Sadiq, I. Mohammed; Mukherjee, Amitava [Centre for Nanobiotechnology, Nano Bio-Medicine Laboratory School of Bio Sciences and Technology VIT University, Vellore - 632014 (India); Chandrasekaran, N., E-mail: nchandrasekaran@vit.ac.in [Centre for Nanobiotechnology, Nano Bio-Medicine Laboratory School of Bio Sciences and Technology VIT University, Vellore - 632014 (India)

    2011-11-30

    Highlights: Black-Right-Pointing-Pointer Effective bioremoval of Cr(III) using bacterial biofilms. Black-Right-Pointing-Pointer Simplified bioreactor was fabricated for the biofilm development and Cr(III) removal. Black-Right-Pointing-Pointer Economically feasible substrate like coarse sand and pebbles were used. - Abstract: Present study deals with the applicability of bacterial biofilms for the bioremoval of trivalent chromium from tannery effluents. A continuous flow reactor was designed for the development of biofilms on different substrates like glass beads, pebbles and coarse sand. The parameters for the continuous flow reactor were 20 ml/min flow rate at 30 Degree-Sign C, pH4. Biofilm biomass on the substrates was in the following sequence: coarse sand > pebbles > glass beads (4.8 Multiplication-Sign 10{sup 7}, 4.5 Multiplication-Sign 10{sup 7} and 3.5 Multiplication-Sign 10{sup 5} CFU/cm{sup 2}), which was confirmed by CLSM. Biofilms developed using consortium of Bacillus subtilis and Bacillus cereus on coarse sand had more surface area and was able to remove 98% of Cr(III), SEM-EDX proved 92.60% Cr(III) adsorption on biofilms supported by coarse sand. Utilization of Bacillus biofilms for effective bioremoval of Cr(III) from chrome tanning effluent could be a better option for tannery industry, especially during post chrome tanning operation.

  4. In vitro pyrogenicity of the diphtheria, tetanus and acellular pertussis components of a trivalent vaccine.

    Science.gov (United States)

    Carlin, Gunnar; Viitanen, Eila

    2005-05-25

    We have earlier found that a trivalent vaccine, containing antigenic components from both Gram-positive and Gram-negative bacteria, induced secretion of the endogenous pyrogen interleukin 6 (IL-6) when added to fresh human blood in vitro. The results of the present study showed that the IL-6 secretion was induced by toxoids derived from the Gram-positive bacterium Corynebacterium diphtheriae. However, fresh whole blood from different donors reacted differently to the stimulation. The blood from some donors induced secretion of large concentrations of IL-6, while the blood from other donors induced essentially no IL-6 secretion as a response to stimulation with diphtheria toxoid or a mixture of diphtheria and tetanus toxoids. Repeated testing over several years using blood from the same donor confirmed a donor-dependency of the reaction. This donor-dependency was only found for the toxoid, since blood from all donors reacted with approximately similar IL-6 production to stimulation by endotoxin from the Gram-negative bacterium Escherichia coli, known to be mediated via the toll-like receptor (TLR) 4. Also, no donor-dependecy was found to highly purified lipoteichoic acid from the Gram-positive bacteria Bacillus subtilis and Staphylococcus aureus, known to be mediated via TLR-2 and TLR-6. The receptors involved in stimulation by diphtheria toxoid are not known, but may differ from those used by endotoxin and lipoteichoic acid.

  5. The endoplasmic reticulum is a target organelle for trivalent dimethylarsinic acid (DMA{sup III})-induced cytotoxicity

    Energy Technology Data Exchange (ETDEWEB)

    Naranmandura, Hua, E-mail: narenman@zju.edu.cn [Department of Pharmacology, Toxicology, and Biochemical Pharmaceutics, College of Pharmaceutical Sciences, Zhejiang University, Hangzhou 310058 (China); Xu, Shi [Department of Pharmacology, Toxicology, and Biochemical Pharmaceutics, College of Pharmaceutical Sciences, Zhejiang University, Hangzhou 310058 (China); Koike, Shota [Graduate School of Pharmaceutical Sciences, Chiba University, Chiba 260-8675 (Japan); Pan, Li Qiang [Department of Pharmacology, Toxicology, and Biochemical Pharmaceutics, College of Pharmaceutical Sciences, Zhejiang University, Hangzhou 310058 (China); Chen, Bin [Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430030 (China); Wang, Yan Wei; Rehman, Kanwal; Wu, Bin [Department of Pharmacology, Toxicology, and Biochemical Pharmaceutics, College of Pharmaceutical Sciences, Zhejiang University, Hangzhou 310058 (China); Chen, Zhe [Zhejiang Hospital of Traditional Chinese Medicine, Zhejiang Chinese Medical University, Hangzhou (China); Suzuki, Noriyuki, E-mail: n-suzuki@p.chiba-u.ac.jp [Graduate School of Pharmaceutical Sciences, Chiba University, Chiba 260-8675 (Japan)

    2012-05-01

    The purpose of present study was to characterize the endoplasmic reticulum stress and generation of ROS in rat liver RLC-16 cells by exposing to trivalent dimethylarsinous acid (DMA{sup III}) and compared with that of trivalent arsenite (iAs{sup III}) and monomethylarsonous acid (MMA{sup III}). Protein kinase-like endoplasmic reticulum kinase (PERK) phosphorylation was significantly induced in cells exposed to DMA{sup III}, while there was no change in phosphorylated PERK (P-PERK) detected in cells after exposure to iAs{sup III} or MMA{sup III}. The generation of reactive oxygen species (ROS) after DMA{sup III} exposure was found to take place specifically in the endoplasmic reticulum (ER), while previous reports showed that ROS was generated in mitochondria following exposure to MMA{sup III}. Meanwhile, cycloheximide (CHX) which is an inhibitor of protein biosynthesis strongly inhibited the DMA{sup III}-induced intracellular ROS generation in the ER and the phosphorylation of PERK, suggesting the induction of ER stress probably occurs through the inhibition of the protein folding process. Activating transcription factor 4 (ATF4) and C/EBP homologous protein (CHOP) mRNA were induced by all three arsenic species, however, evidence suggested that they might be induced by different pathways in the case of iAs{sup III} and MMA{sup III}. In addition, ER resident molecular chaperone glucose-regulated protein78 (GRP78) was not affected by trivalent arsenicals, while it was induced in positive control only at high concentration (Thapsigargin;Tg), suggesting the GRP78 is less sensitive to low levels of ER stress. In summary, our findings demonstrate that the endoplasmic reticulum is a target organelle for DMA{sup III}-induced cytotoxicity. Highlights: ►ER is a target organelle for trivalent DMA{sup III}-induced cytotoxicity. ►Generation of ROS in ER can be induced specially by trivalent DMA{sup III}. ►ER-stress and generation of ROS are caused by the increase in

  6. Protein methylation in pea chloroplasts

    International Nuclear Information System (INIS)

    Niemi, K.J.; Adler, J.; Selman, B.R.

    1990-01-01

    The methylation of chloroplast proteins has been investigated by incubating intact pea (Pisum sativum) chloroplasts with [ 3 H-methyl]-S-adenosylmethionine. Incubation in the light increases the amount of methylation in both the thylakoid and stromal fractions. Numerous thylakoid proteins serve as substrates for the methyltransfer reactions. Three of these thylakoid proteins are methylated to a significantly greater extent in the light than in the dark. The primary stromal polypeptide methylated is the large subunit of ribulose bisphosphate carboxylase/oxygenase. One other stromal polypeptide is also methylated much more in the light than in the dark. Two distinct types of protein methylation occur. One methylinkage is stable to basic conditions whereas a second type is base labile. The base-stable linkage is indicative of N-methylation of amino acid residues while base-lability is suggestive of carboxymethylation of amino acid residues. Labeling in the light increases the percentage of methylation that is base labile in the thylakoid fraction while no difference is observed in the amount of base-labile methylations in light-labeled and dark-labeled stromal proteins. Also suggestive of carboxymethylation is the detection of volatile [ 3 H]methyl radioactivity which increases during the labeling period and is greater in chloroplasts labeled in the light as opposed to being labeled in the dark; this implies in vivo turnover of the [ 3 H]methyl group

  7. Methylation of food commodities during fumigation with methyl bromide

    International Nuclear Information System (INIS)

    Starratt, A.N.; Bond, E.J.

    1990-01-01

    Sites of methylation in several commodities (wheat, oatmeal, peanuts, almonds, apples, oranges, maize, alfalfa and potatoes) during fumigation with 14 C-methyl bromide were studied. Differences were observed in levels of the major volatiles: methanol, dimethyl sulphide and methyl mercaptan, products of O- and S-methylation, resulting from treatment of the fumigated materials with 1N sodium hydroxide. In studies of maize and wheat, histidine was the amino acid which underwent the highest level of N-methylation. (author). 24 refs, 3 tabs

  8. Effect of trivalent transition metal ion substitution in Dy2O3 system

    International Nuclear Information System (INIS)

    Dhilip, M.; Saravana Kumar, K.; Anbarasu, V.

    2015-01-01

    One of the very promising approaches to create novel materials is to combine different physical properties in one material to achieve rich functionality. Magnetoelectric multiferroics are attracting attention for fundamental physics due to their unique coupling behaviour between ferroelectricity, ferromagnetism and ferroelasticity and also because of their promising applications for devices in spintronics, information storage, sensing and actuation. The existence of spontaneous magnetization in the perovskite like phase (layer of perovskite) has encouraged exploring the possibility of fabrication of a multiferroic material for multifunctional devices using the concept of magnetoelectric effect. The rare earth orthoferrites (LnFeO 3 where, Ln = La, Sm, Gd, Dy, Er and Yb) are a class of materials having potential for various applications. These compounds and metal ion substituted ferrites crystallising in perovskite structure show promise as catalysts gas separators, cathodes in solid oxide fuel cells, sensor materials, magneto-optic materials and as spin valves. In this present work, Fe substituted in Dysprosium Oxide compounds were prepared by standard solid state reaction at a temperature of 1300℃. The structural analysis of the prepared samples was characterized with powder X-Ray Diffraction technique and the lattice parameters were calculated with PodwerX indexing software. The structural analysis reveals that the substitution of Fe in Dy 2 O 3 system leads to change of crystalline structure from Cubic to Tetragonal. Further, decreasing trend of volume of the unit cell confirms the occupation of smaller ionic radii element Fe in the Dy site of Dy 2 O 3 system. Hence the possibilities of incorporation of trivalent transition metal ion in to the host Dy 2 O 3 site were analyzed. (author)

  9. A systematic analysis of the spectra of trivalent actinide chlorides in D3h site symmetry

    International Nuclear Information System (INIS)

    Carnall, W.T.

    1989-11-01

    The optical spectra of actinide ions in the compound AnCl 3 and doped into single crystal LaCl 3 were interpreted in terms of transitions within 5f N configurations. Energy-level calculations were carried out using an effective operator Hamiltonian, the parameters of which were determined by fitting experimental data. Atomic and crystal-field matrices were diagonalized simultaneously assuming an approximate D 3h site symmetry. The spectroscopic data were taken from the literature but in most cases supplemented by unpublished measurements in absorption and in fluorescence. Spectroscopic data for each ion were analyzed independently, then the model parameters were intercompared and in many cases adjusted such that in the final fitting process the principal interactions showed uniform trends in parameter values with increasing atomic number. Consistent with analyses of the spectra of lanthanide ions in both LaCl 3 and LaF 3 , abrupt changes in magnitude of certain crystal-field parameters were found near the center of the 5f N -series. This resulted in two groups of parameter values, but with consistent trends for both halves of the series, and generally very good agreement between observed and computed energies. A new energy level chart based on computed crystal-field level energies for each trivalent actinide ion has been prepared. in addition, the parameters of the atomic part of each 5f N Hamiltonian were used to calculate the matrix elements of U (λ) for selected transitions. The values were tabulated to facilitate calculation of intensity-related parameters for 5f N -transitions using the Judd-Ofelt theory. 44 refs., 10 figs., 3 tabs

  10. Methylation in hepatocellular carcinoma

    Directory of Open Access Journals (Sweden)

    Regina M. Santella

    2007-02-01

    Full Text Available

    The development of HCC is a complex, multistep, multistage process. The molecular pathogenesis of HCC appears to involve multiple genetic aberrations in the molecular control of hepatocyte proliferation, differentiation and death and the maintenance of genomic integrity. This process is influenced by the cumulative activation and inactivation of oncogenes, tumor suppressor genes and other genes. p53, a tumor suppressor gene, is the most frequently mutated gene in human cancers. There is also a striking sequence specific binding and induction of mutations by AFB1 at codon 249 of p53 in HCC.

    Epigenetic alterations are also involved in cancer development and progression. Methylation of promoter CpG islands is associated with inhibition of transcriptional initiation and permanent silencing of downstream genes.

    It is now known that most important tumor suppressor genes are inactivated, not only by mutations and deletions but also by promoter methylation. Several studies indicated that p16, p15, RASSF1A, MGMT, and GSTP1 promoter hypermethylation are prevalent in HCC. In addition, geographic variation in the methylation status of tumor DNA indicates that environmental factors may influence the frequent and concordant degree of hypermethylation in multiple genes in HCC and that epigeneticenvironmental interactions may be involved in hepatocarcinogenesis. We have found significant relationships between promoter methylation and AFB1-DNA adducts confirming the impact of environmental exposures on gene methylation.

    DNA isolated from serum or plasma of cancer patients frequently contains the same genetic and

  11. Selective extraction of trivalent actinides with hard-soft mixed donor ligands: role of intra-ligand synergism

    International Nuclear Information System (INIS)

    Ghanty, Tapan K.

    2016-01-01

    In recent years, considerable attention has been given to understand the coordination chemistry of trivalent lanthanide (Ln) and actinide (An) with various ligands because of its close link with the nuclear waste management processes. It is well known that lanthanide-actinide separation is a challenging and difficult task because of very similar chemical properties of these two series of ions, which are associated with similar ionic radii and coordination numbers. Recently, we have introduced a new concept, 'intra-ligand synergism', where hard donor atom, such as, oxygen preferentially binds to trivalent actinides (An(III)) as compared to the valence iso-electronic trivalent lanthanides (Ln(III)) in presence of another soft donor centre. In the present work, the conventional concept of selective complexation of actinides with soft donor ligands (either S or N donor) has been modified through exploiting this concept, and thereby the higher selectivity of 1,10-phenanthroline-2,9-dicarboxylamide (PDAM) based ligands, namely PDAM and its isobutyl and decyl derivatives towards Am(III) ion has been predicted theoretically through density functional calculations. Subsequently, several such amide derivatives have been synthesized to optimize the solubility of the ligands in organic phase. Finally, solvent extraction experiments have been carried out to validate the theoretical prediction on the selectivity of oxygen donor ligands towards Am(III) as compared to Eu(III), and a maximum separation factor of about 51 has been achieved experimentally using 2,9-bis(N-decylaminocarbonyl)-1,10-phenanthroline ligand. The separation factor is increased with the decrease in pH, which is very interesting since extraction of the Am 3+ ion is considered to be important under highly acidic conditions from the nuclear waste management point of view. (author)

  12. Blockade and enhancement of glutamate receptor responses in Xenopus oocytes by methylated arsenicals

    Energy Technology Data Exchange (ETDEWEB)

    Krueger, Katharina; Gruner, Janina; Madeja, Michael; Musshoff, Ulrich [Universitaetsklinikum Muenster, Institut fuer Physiologie I, Muenster (Germany); Hartmann, Louise M.; Hirner, Alfred V. [Universitaet Duisburg-Essen, Institut fuer Umweltanalytik, Essen (Germany); Binding, Norbert [Universitaetsklinikum Muenster, Institut fuer Arbeitsmedizin, Muenster (Germany)

    2006-08-15

    Pentavalent and trivalent organoarsenic compounds belong to the major metabolites of inorganic arsenicals detected in humans. Recently, the question was raised whether the organic arsenicals represent metabolites of a detoxification process or methylated species with deleterious biological effects. In this study, the effects of trivalent arsenite (AsO{sub 3} {sup 3-}; iA{sup III}), the pentavalent organoarsenic compounds monomethylarsonic acid (CH{sub 3}AsO(OH){sub 2}; MMA{sup V}) and dimethylarsinic acid ((CH{sub 3}){sub 2}AsO(OH); DMA{sup V}) and the trivalent compounds monomethylarsonous acid (CH{sub 3}As(OH){sub 2}, MMA{sup III}) and dimethylarsinous acid ((CH{sub 3}){sub 2}As(OH); DMA{sup III}) were tested on glutamate receptors and on voltage-operated potassium and sodium channels heterologously expressed in Xenopus oocytes. Membrane currents of ion channels were measured by conventional two-electrode voltage-clamp techniques. The effects of arsenite were tested in concentrations of 1-1,000 {mu}mol/l and the organic arsenical compounds were tested in concentrations of 0.1-100 {mu}mol/l. We found no significant effects on voltage-operated ion channels; however, the arsenicals exert different effects on glutamate receptors. While MMA{sup V} and MMA{sup III} significantly enhanced ion currents through N-methyl-d-aspartate (NMDA) receptor ion channels with threshold concentrations <10 {mu}mol/l, DMA{sup V} and DMA{sup III} significantly reduced NMDA-receptor mediated responses with threshold concentrations <0.1 {mu}mol/l; iA{sup III} had no effects on glutamate receptors of the NMDA type. MMA{sup III} and DMA{sup V} significantly reduced ion currents through {alpha}-amino-3-hydroxy-5-methylisoxazole-4-propionic acid (AMPA)-receptor ion channels with threshold concentrations <10 {mu}mol/l (MMA{sup III}) and <1 {mu}mol/l (DMA{sup V}). MMA{sup V} and iA{sup III} had no significant effects on glutamate receptors of the AMPA type. The effects of MMA{sup V}, MMA

  13. Comparative evaluation of adverse effects in the use of powder trivalent antivenom and liquid antivenoms in Bothrops snake bites

    Directory of Open Access Journals (Sweden)

    Iran Mendonça da Silva

    2012-08-01

    Full Text Available INTRODUCTION: Snake bite, a problem in public health, generally occurs where there is no electric power. METHODS: A comparative clinical study was conducted with 102 victims of Bothrops snake bite, from the state of Amazonas, Brazil; 58 victims were treated with liofilizated trivalent antivenom serum (SATL and 44 victims treated with liquid bivalent and monovalent antivenom serum (SAMBL. RESULTS: 17% (10/58 of patients presented adverse effects with the SATL and 25% (11/44 with the SAMBL. CONCLUSIONS: There was no statistic difference in number of adverse effects between the two types of snake bite antivenom.

  14. The effect of doping crystals of tgs with some di- and trivalent ions on its: (ii) polarization and piezoelectricity

    OpenAIRE

    Gaffar, M. A [محمد عبد العزيز جعفر; Mohamed, A. A.; Al-Muraikhi, M.; Al-Houty, L. I.

    1987-01-01

    The polarization, coercive field,piezoelectricity and electromechanical coupling for pure and doped single crystals of TGS arp investigated in the temperature range 77-325 K. The influence of the divalent ions Ni 2+, Cu2 and Co2 and the trivalent ions Cr34^ and Fe3'1' on the temperature of phase transition, the hysteresis loops of polarization and the seconed coefficient in the expansion of the free energy in powers of polarization is examined. The temperature dependence of the spontaneous po...

  15. Evaluation of cross-protection by immunization with an experimental trivalent companion animal periodontitis vaccine in the mouse periodontitis model.

    Science.gov (United States)

    Hardham, John; Sfintescu, Cornelia; Evans, Richard T

    2008-03-01

    Companion animal periodontal disease is one of the most prevalent diseases seen by veterinarians. The goal of this study was to evaluate the vaccine performance of a trivalent canine periodontitis vaccine in the mouse oral challenge model of periodontitis. Mice vaccinated subcutaneously with an inactivated, whole-cell vaccine preparation of Porphyromonas denticanis, Porphyromonas gulae, and Porphyromonas salivosa displayed significantly reduced alveolar bone loss in response to heterologous and cross-species challenges as compared to sham vaccinated animals. Based on the results of these studies, a periodontitis vaccine may be a useful tool in preventing the initiation and progression of periodontitis caused by the most commonly isolated pigmenting anaerobic bacteria in animals.

  16. DNA methylation and memory formation.

    Science.gov (United States)

    Day, Jeremy J; Sweatt, J David

    2010-11-01

    Memory formation and storage require long-lasting changes in memory-related neuronal circuits. Recent evidence indicates that DNA methylation may serve as a contributing mechanism in memory formation and storage. These emerging findings suggest a role for an epigenetic mechanism in learning and long-term memory maintenance and raise apparent conundrums and questions. For example, it is unclear how DNA methylation might be reversed during the formation of a memory, how changes in DNA methylation alter neuronal function to promote memory formation, and how DNA methylation patterns differ between neuronal structures to enable both consolidation and storage of memories. Here we evaluate the existing evidence supporting a role for DNA methylation in memory, discuss how DNA methylation may affect genetic and neuronal function to contribute to behavior, propose several future directions for the emerging subfield of neuroepigenetics, and begin to address some of the broader implications of this work.

  17. Effect of different culture systems on the production of foot and mouth disease trivalent vaccine

    Directory of Open Access Journals (Sweden)

    Amr Ismail Hassan

    2016-01-01

    Full Text Available Aim: This study aims to determine the effect of the stationary rawx, roller, and the suspension cell culture systems on the total virus yield infectivity and antigenicity. Materials and Methods: Three serotypes of foot and mouth disease virus (FMDV (serotype A, O and SAT-2 were inoculated separately into baby hamster kidney-21 cell line in rawx, roller, and suspension cultivation systems using multiplicity of infection (1:100. Samples were taken from the total virus yield from each system at 15, 18, 21, and 24 h post-inoculation. Testing the total virus yield infectivity through virus titration and antigenicity through estimation of complement fixing titer and 146S content and evaluation of the potency of the vaccine prepared from the different cultivation systems were done. Results: The results showed that the FMDV titer of serotype A, O, and SAT-2 obtained from the roller cultivation system showed the highest level followed by suspension cultivation system then the rawx cultivation system. The FMDV titer showed its highest level at 21 h post-inoculation in all the cultivation systems and then decline at 24 h post-inoculation. The antigenicity reached its highest value content at 18 h post-inoculation either by complement fixation test or by quantifying the 146S intact virion. Montanide ISA 206 oil inactivated trivalent vaccines were prepared from the tested serotypes (A Iran O5. O Panasia and SAT-2/EGY/2012 harvested at 18 h post-inoculation from the 3 culture systems. The results of tracing the antibody response showed that the mean antibody response from the roller cultivation system start its protective antibody titer earlier at 2 weeks post-vaccination (WPV than the vaccine prepared from the other two cultivation system and the immune protection period lasts longer for 36 WPV for the roller cultivation system vaccine than the other two cultivation systems. Conclusion: The best cultivation system used for the production of FMD vaccine

  18. Whole-genome methylation caller designed for methyl- DNA ...

    African Journals Online (AJOL)

    etchie

    2013-02-20

    Feb 20, 2013 ... Key words: Methyl-DNA immunoprecipitation, next-generation sequencing, Hidden ... its response to environmental cues. .... have a great potential to become the most cost-effective ... hg18 reference genome (set to 0 if not present in retrieved reads). ..... DNA methylation patterns and epigenetic memory.

  19. A chimeric protein of aluminum-activated malate transporter generated from wheat and Arabidopsis shows enhanced response to trivalent cations.

    Science.gov (United States)

    Sasaki, Takayuki; Tsuchiya, Yoshiyuki; Ariyoshi, Michiyo; Ryan, Peter R; Yamamoto, Yoko

    2016-07-01

    TaALMT1 from wheat (Triticum aestivum) and AtALMT1 from Arabidopsis thaliana encode aluminum (Al)-activated malate transporters, which confer acid-soil tolerance by releasing malate from roots. Chimeric proteins from TaALMT1 and AtALMT1 (Ta::At, At::Ta) were previously analyzed in Xenopus laevis oocytes. Those studies showed that Al could activate malate efflux from the Ta::At chimera but not from At::Ta. Here, functions of TaALMT1, AtALMT1 and the chimeric protein Ta::At were compared in cultured tobacco BY-2 cells. We focused on the sensitivity and specificity of their activation by trivalent cations. The activation of malate efflux by Al was at least two-fold greater in the chimera than the native proteins. All proteins were also activated by lanthanides (erbium, ytterbium, gadolinium, and lanthanum), but the chimera again released more malate than TaALMT1 or AtALMT1. In Xenopus oocytes, Al, ytterbium, and erbium activated inward currents from the native TaALMT1 and the chimeric protein, but gadolinium only activated currents from the chimera. Lanthanum inhibited currents from both proteins. These results demonstrated that function of the chimera protein was altered compared to the native proteins and was more responsive to a range of trivalent cations when expressed in plant cells. Copyright © 2016 Elsevier B.V. All rights reserved.

  20. Trivalent chromium removal from wastewater using low cost activated carbon derived from agricultural waste material and activated carbon fabric cloth

    International Nuclear Information System (INIS)

    Mohan, Dinesh; Singh, Kunwar P.; Singh, Vinod K.

    2006-01-01

    An efficient adsorption process is developed for the decontamination of trivalent chromium from tannery effluents. A low cost activated carbon (ATFAC) was prepared from coconut shell fibers (an agricultural waste), characterized and utilized for Cr(III) removal from water/wastewater. A commercially available activated carbon fabric cloth (ACF) was also studied for comparative evaluation. All the equilibrium and kinetic studies were conducted at different temperatures, particle size, pHs, and adsorbent doses in batch mode. The Langmuir and Freundlich isotherm models were applied. The Langmuir model best fit the equilibrium isotherm data. The maximum adsorption capacities of ATFAC and ACF at 25 deg. C are 12.2 and 39.56 mg/g, respectively. Cr(III) adsorption increased with an increase in temperature (10 deg. C: ATFAC-10.97 mg/g, ACF-36.05 mg/g; 40 deg. C: ATFAC-16.10 mg/g, ACF-40.29 mg/g). The kinetic studies were conducted to delineate the effect of temperature, initial adsorbate concentration, particle size of the adsorbent, and solid to liquid ratio. The adsorption of Cr(III) follows the pseudo-second-order rate kinetics. From kinetic studies various rate and thermodynamic parameters such as effective diffusion coefficient, activation energy and entropy of activation were evaluated. The sorption capacity of activated carbon (ATFAC) and activated carbon fabric cloth is comparable to many other adsorbents/carbons/biosorbents utilized for the removal of trivalent chromium from water/wastewater

  1. A thermodynamical and structural study on the complexation of trivalent lanthanides with a polycarboxylate based concrete superplasticizer.

    Science.gov (United States)

    Fröhlich, Daniel R; Maiwald, Martin M; Taube, Franziska; Plank, Johann; Panak, Petra J

    2017-03-21

    The complexation of trivalent lanthanides with a commercial polycarboxylate based concrete superplasticizer (Glenium® 51) is investigated using different spectroscopic techniques. Time-resolved laser fluorescence spectroscopy (TRLFS) in combination with a charge neutralization model is used to determine temperature dependent conditional stability constants (log β'(T)) for the complexation of Eu(iii) with Glenium® 51 in 0.1 mol kg -1 NaCl solution in the temperature range of 20-90 °C. Only one complex species is observed, and log β'(T) (given in kg per mol eq) shows a very slight increase with temperature from 7.5 to 7.9. The related conditional molar reaction enthalpy (Δ r H' m ) and entropy (Δ r S' m ) obtained using the Van't Hoff equation show that the complexation reaction is slightly endothermic and entropy driven. The thermodynamic investigations are complemented by structural data for complexes formed with Gd(iii) or Tb(iii) and Glenium® 51 using extended X-ray absorption fine structure (EXAFS) spectroscopy. The results imply a non-chelate coordination of the trivalent metals through approximately three carboxylic functions of the polycarboxylate comb polymer which are attached predominantly in a bidentate fashion to the lanthanide under the given experimental conditions.

  2. Amide mediated enhancement of sorption efficiency of trivalent f-elements on functionalized carbon nanotube: evidence of physiosorption

    International Nuclear Information System (INIS)

    Gupta, Nishesh K.; Sengupta, Arijit; Rane, Vinayak G.; Kadam, R.M.

    2017-01-01

    Amide Functionalized multi-walled carbon nanotube (CNT-DHA) was found to enhance the sorption efficiency of trivalent lanthanides and actinides from aqueous acidic solution. Langmuir, Freundlich, Dubinin-Radushkevich (D-R) and Temkin isotherm models were employed to understand the sorption mechanism revealing the predominance of Fruendlich isotherm. The sorption energy evaluated from D-R isotherm revealed the sorption process is physisorption, which was confirmed by the no shift in the IR frequency of amide functionality of carbon nanotube on sorption. The EPR spectra of the Gd"3"+ sorbed on carbon nanotube also showed no perturbation on the local environment of Gd"3"+ on sorption again revealing the physisorption. Analysis of the sorption kinetics through Lagergren's first order kinetics, intra particle diffusion model and pseudo second order kinetics revealed that the sorption kinetics followed pseudo second order kinetics for Am"3"+ and Eu"3"+ with rate constants 4.04E-05mg g"-"1 min"-"1 and 8.27E-05 mg g"-"1 min"-"1 respectively. The radiolytic stability of CNT-DHA was evaluated and found to be satisfactory. EDTA was found to strip the trivalent lanthanides and actinides almost quantitatively. (author)

  3. DNA methylation in metabolic disorders

    DEFF Research Database (Denmark)

    Barres, Romain; Zierath, Juleen R

    2011-01-01

    DNA methylation is a major epigenetic modification that controls gene expression in physiologic and pathologic states. Metabolic diseases such as diabetes and obesity are associated with profound alterations in gene expression that are caused by genetic and environmental factors. Recent reports...... have provided evidence that environmental factors at all ages could modify DNA methylation in somatic tissues, which suggests that DNA methylation is a more dynamic process than previously appreciated. Because of the importance of lifestyle factors in metabolic disorders, DNA methylation provides...... a mechanism by which environmental factors, including diet and exercise, can modify genetic predisposition to disease. This article considers the current evidence that defines a role for DNA methylation in metabolic disorders....

  4. Investigations on the nephrotoxicity and hepatotoxicity of trivalent and hexavalent chromium compounds.

    Science.gov (United States)

    Dartsch, P C; Hildenbrand, S; Kimmel, R; Schmahl, F W

    1998-09-01

    In contrast to trivalent chromium (Cr(III)) compounds, hexavalent chromium ((Cr(VI)) compounds are oxidizing agents capable of directly inducing tissue damage and possessing carcinogenic, mutagenic and teratogenic potency. After oral or dermal absorption of Cr(VI), the kidney is the main target organ for chromium accumulation, which might result in acute tubular necrosis in humans. In contrast, an acute toxic effect of Cr(VI) on the liver has not yet been described. Therefore, we used two established epithelial cell lines from the kidney (Opossum kidney cells) and the liver (Hep G2 cells) to design an in vitro-assay which is able to examine acute toxic effects of chromium compounds. Cells of both cell lines were treated with various concentrations of Cr(III) and Cr(VI) ranging from 0.01 micromol/l to 1 mmol/l for 24 h. Thereafter, cell morphology, organization of the intracellular cytoskeleton, number of viable cells and mean cell volume were examined. The results show that Cr(VI), but not Cr(III), has an acute cytotoxic effect and causes a dose-dependent loss in cell viability. The effective dose that caused 50% of cell death was 5 micromol/l for kidney epithelial cells and 50 micromol/l for liver epithelial cells. This means that kidney epithelial cells are 10 times more sensitive towards Cr(VI) treatment than liver epithelial cells and this might explain the known nephrotoxicity in vivo. The loss in cell viability was accompanied by a rounding and detachment of the cells and a marked reduction of intracellular F-actin-containing stress fibers. Microtubules and intermediate-sized filaments were observed to be unaffected. Only in the case of kidney epithelial cells, a dose-dependent cell volume increase was observed after Cr(VI) treatment at concentrations up to 50 micromol/l. At higher concentrations, the cell volume decreased due to the high number of cells undergoing lysis and the appearance of cellular fragments. Various chloride channel blockers with

  5. Application of a room temperature ionic liquid for nuclear spent fuel reprocessing: speciation of trivalent europium and solvatation effects

    International Nuclear Information System (INIS)

    Moutiers, G.; Mekki, S.; Billard, I.

    2007-01-01

    One of the solutions proposed for the optimization of the long term storage and conditioning of spent nuclear fuel is to separate actinide and lanthanide both from each other and from other less radioactive metallic species. The industrial proposed processes, based on liquid liquid extraction steps, involve solvents with non negligible vapour pressure and may generate contaminated liquid wastes that will have to be reprocessed. During the last decade, some room-temperature ionic liquids have been studied and integrated into industrial processes. The interest on this class of solvent came out from their 'green' properties (non volatile, non flammable, recyclable, etc...), but also from the variability of their physico-chemical properties (stability, hydrophobicity, viscosity) as a function of the RTIL chemical composition. Indeed, it has been shown that classical chemical industrial processes could be transferred into those media, even more improved, while a certain number of difficulties arising from using traditional solvent can be avoided. In this respect, it could be promising to investigate the ability to use room temperature ionic liquid into the spent nuclear fuel reprocessing field. The aim of this this study is to test the ability of the specific ionic liquid bumimTf 2 N to allow trivalent europium extraction. The choice of this metal is based on the chemical analogy with trivalent minor actinides Curium and Americium which are contributing the greatest part of the long-lived high level radioactive wastes. Handling these elements needs to be very cautious for the safety and radioprotection aspect. Moreover, europium is a very sensitive luminescent probe to its environment even at the microscopic scale. The report is structured with four parts. In a first chapter, we present the main physico-chemical properties of an imidazolium-based ionic liquid family, and then we choose the ionic liquid bumimTf 2 N for the whole thesis and start with the electrochemical

  6. Cost-utility of quadrivalent versus trivalent influenza vaccine in Brazil - comparison of outcomes from different static model types.

    Science.gov (United States)

    Van Bellinghen, Laure-Anne; Marijam, Alen; Tannus Branco de Araujo, Gabriela; Gomez, Jorge; Van Vlaenderen, Ilse

    Influenza burden in Brazil is considerable with 4.2-6.4 million cases in 2008 and influenza-like-illness responsible for 16.9% of hospitalizations. Cost-effectiveness of influenza vaccination may be assessed by different types of models, with limitations due to data availability, assumptions, and modelling approach. To understand the impact of model complexity, the cost-utility of quadrivalent versus trivalent influenza vaccines in Brazil was estimated using three distinct models: a 1-year decision tree population model with three age groups (FLOU); a more detailed 1-year population model with five age groups (FLORA); and a more complex lifetime multi-cohort Markov model with nine age groups (FLORENCE). Analysis 1 (impact of model structure) compared each model using the same data inputs (i.e., best available data for FLOU). Analysis 2 (impact of increasing granularity) compared each model populated with the best available data for that model. Using the best data for each model, the discounted cost-utility ratio of quadrivalent versus trivalent influenza vaccine was R$20,428 with FLOU, R$22,768 with FLORA (versus R$20,428 in Analysis 1), and, R$19,257 with FLORENCE (versus R$22,490 in Analysis 1) using a lifetime horizon. Conceptual differences between FLORA and FLORENCE meant the same assumption regarding increased all-cause mortality in at-risk individuals had an opposite effect on the incremental cost-effectiveness ratio in Analysis 2 versus 1, and a proportionally higher number of vaccinated elderly in FLORENCE reduced this ratio in Analysis 2. FLOU provided adequate cost-effectiveness estimates with data in broad age groups. FLORA increased insights (e.g., in healthy versus at-risk, paediatric, respiratory/non-respiratory complications). FLORENCE provided greater insights and precision (e.g., in elderly, costs and complications, lifetime cost-effectiveness). All three models predicted a cost per quality-adjusted life year gained for quadrivalent versus

  7. Benzene-centred tripodal diglycolamides for the sequestration of trivalent actinides : Metal ion extraction and luminescence spectroscopic investigations in a room temperature ionic liquid

    NARCIS (Netherlands)

    Ansari, Seraj Ahmad; Mohapatra, Prasanta Kumar; Leoncini, Andrea; Huskens, Jurriaan; Verboom, Willem

    2017-01-01

    Three benzene-centred tripodal diglycolamide (Bz-T-DGA) ligands, where the diglycolamide (DGA) moieties are attached to a central benzene ring through ethylene spacers (LI), amide groups (LII) or ether linkages (LIII), were evaluated for their extraction behaviour towards trivalent actinide and

  8. Zn- and Co-based layered double hydroxides: prediction of the a parameter from the fraction of trivalent cations and vice versa

    Science.gov (United States)

    Richardson, Ian G.

    2013-01-01

    A recently proposed method to calculate the a parameter of the unit cell of layered double hydroxides from the fraction of trivalent cations is extended to Zn- and Co-based phases. It is shown to be useful as a sanity test for extant and future structure determinations and computer-simulation studies. PMID:23873067

  9. Zn- and Co-based layered double hydroxides: prediction of the a parameter from the fraction of trivalent cations and vice versa

    OpenAIRE

    Richardson, Ian G.

    2013-01-01

    A recently proposed method to calculate the a parameter of the unit cell of layered double hydroxides from the fraction of trivalent cations is extended to Zn- and Co-based phases. It is shown to be useful as a sanity test for extant and future structure determinations and computer-simulation studies.

  10. AS03-adjuvanted versus non-adjuvanted inactivated trivalent influenza vaccine against seasonal influenza in elderly people: a phase 3 randomised trial

    NARCIS (Netherlands)

    McElhaney, J.E.; Beran, J.; Devaster, J.M.; Esen, M.; Launay, O.; Leroux-Roels, G.; Ruiz-Palacios, G.M.; Essen, G.A. van; Caplanusi, A.; Claeys, C.; Durand, C.; Duval, X.; Idrissi, M. El; Falsey, A.R.; Feldman, G.; Frey, S.E.; Galtier, F.; Hwang, S.J.; Innis, B.L.; Kovac, M.; Kremsner, P.; McNeil, S.; Nowakowski, A.; Richardus, J.H.; Trofa, A.; Oostvogels, L.; Verheugt, F.W.; et al.,

    2013-01-01

    BACKGROUND: We aimed to compare AS03-adjuvanted inactivated trivalent influenza vaccine (TIV) with non-adjuvanted TIV for seasonal influenza prevention in elderly people. METHODS: We did a randomised trial in 15 countries worldwide during the 2008-09 (year 1) and 2009-10 (year 2) influenza seasons.

  11. Trivalent influenza vaccine in patients on haemodialysis: impaired seroresponse with differences for A-H3N2 and A-H1N1 vaccine components

    NARCIS (Netherlands)

    W.E.Ph. Beyer (Walter); D.J. Versluis; P. Kramer; P.P.N.M. Diderich (Philip); W. Weimar (Willem); N. Masurel (Nic)

    1987-01-01

    textabstractOne hundred and one patients on haemodialysis, 21 patients on peritoneal dialysis and 30 healthy controls received a trivalent split vaccine containing 15 micrograms haemagglutinin of a recent influenza A-H3N2, influenza A-H1N1 and influenza B strain, respectively. Antibody production

  12. Co-ordination properties of diglycol-amide (DGA) to trivalent curium and lanthanides studied by XAS, XRD and XPS methods

    International Nuclear Information System (INIS)

    Yaita, T.; Hirata, M.; Narita, H.; Tachimori, S.; Yamamoto, H.; Edelstein, N.M.; Bucher, J.J.; Shuh, D.K.; Rao, L.

    2001-01-01

    Co-ordination properties of diglycol-amide (DGA) to trivalent curium and to the trivalent lanthanides were studied by the EXAFS, the XRD and the XPS methods. The structural determinations by both the crystal XRD and the solution EXAFS methods showed that the DGA co-ordinated to the trivalent lanthanide ion in a tridentate fashion: co-ordination of three oxygen atoms of each ligand to the metal ion. The bond distances of Er-O (carbonyl) and Er-O (ether) in the Er-DGA complex were 2.35 Angstrom, and 2.46 Angstrom, respectively, while the atom distances of Cm-O (carbonyl) and Cm-O (ether) in the Cm-DGA complex were 2.42 Angstrom and 3.94 Angstrom, respectively from the EXAFS data for the Cm-DGA complex. Accordingly, the DGA would behave only as a semi-tridentate in the co-ordination to trivalent curium in solution. We determined the valence band structures of the Er-DGA complex by the XPS in order to clarify the bond properties of the complex, and assigned the XPS spectrum by using the DV-DS molecular orbital calculation method. (authors)

  13. Role of the metal oxidation state in the SNS-Cr catalyst for ethylene trimerization: Isolation of Di- and trivalent cationic intermediates

    NARCIS (Netherlands)

    Jabri, A.; Temple, C.N.; Crewdson, P.; Gambarotta, S.; Korobkov, I.V.; Duchateau, R.

    2006-01-01

    The reaction of the highly selective [CySCH2CH2N(H)CH2CH2SCy]CrCl3 catalyst precursor with alkyl aluminum activators was examined with the aim of isolating reactive intermediates. Reaction with Me3Al afforded a cationic trivalent chromium alkyl species

  14. Methylation-Specific PCR Unraveled

    Directory of Open Access Journals (Sweden)

    Sarah Derks

    2004-01-01

    Full Text Available Methylation‐specific PCR (MSP is a simple, quick and cost‐effective method to analyze the DNA methylation status of virtually any group of CpG sites within a CpG island. The technique comprises two parts: (1 sodium bisulfite conversion of unmethylated cytosine's to uracil under conditions whereby methylated cytosines remains unchanged and (2 detection of the bisulfite induced sequence differences by PCR using specific primer sets for both unmethylated and methylated DNA. This review discusses the critical parameters of MSP and presents an overview of the available MSP variants and the (clinical applications.

  15. A Replication-Defective Human Type 5 Adenovirus-Based Trivalent Vaccine Confers Complete Protection against Plague in Mice and Nonhuman Primates.

    Science.gov (United States)

    Sha, Jian; Kirtley, Michelle L; Klages, Curtis; Erova, Tatiana E; Telepnev, Maxim; Ponnusamy, Duraisamy; Fitts, Eric C; Baze, Wallace B; Sivasubramani, Satheesh K; Lawrence, William S; Patrikeev, Igor; Peel, Jennifer E; Andersson, Jourdan A; Kozlova, Elena V; Tiner, Bethany L; Peterson, Johnny W; McWilliams, David; Patel, Snehal; Rothe, Eric; Motin, Vladimir L; Chopra, Ashok K

    2016-07-01

    Currently, no plague vaccine exists in the United States for human use. The capsular antigen (Caf1 or F1) and two type 3 secretion system (T3SS) components, the low-calcium-response V antigen (LcrV) and the needle protein YscF, represent protective antigens of Yersinia pestis We used a replication-defective human type 5 adenovirus (Ad5) vector and constructed recombinant monovalent and trivalent vaccines (rAd5-LcrV and rAd5-YFV) that expressed either the codon-optimized lcrV or the fusion gene designated YFV (consisting of ycsF, caf1, and lcrV). Immunization of mice with the trivalent rAd5-YFV vaccine by either the intramuscular (i.m.) or the intranasal (i.n.) route provided protection superior to that with the monovalent rAd5-LcrV vaccine against bubonic and pneumonic plague when animals were challenged with Y. pestis CO92. Preexisting adenoviral immunity did not diminish the protective response, and the protection was always higher when mice were administered one i.n. dose of the trivalent vaccine (priming) followed by a single i.m. booster dose of the purified YFV antigen. Immunization of cynomolgus macaques with the trivalent rAd5-YFV vaccine by the prime-boost strategy provided 100% protection against a stringent aerosol challenge dose of CO92 to animals that had preexisting adenoviral immunity. The vaccinated and challenged macaques had no signs of disease, and the invading pathogen rapidly cleared with no histopathological lesions. This is the first report showing the efficacy of an adenovirus-vectored trivalent vaccine against pneumonic plague in mouse and nonhuman primate (NHP) models. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

  16. Antibody Responses with Fc-Mediated Functions after Vaccination of HIV-Infected Subjects with Trivalent Influenza Vaccine

    DEFF Research Database (Denmark)

    Kristensen, Anne B; Lay, William N; Ana-Sosa-Batiz, Fernanda

    2016-01-01

    to immunize this at-risk group. IMPORTANCE: Infection with HIV is associated with increasing disease severity following influenza infections, and annual influenza vaccinations are recommended for this target group. However, HIV-infected individuals respond relatively poorly to vaccination compared to healthy......This study seeks to assess the ability of seasonal trivalent inactivated influenza vaccine (TIV) to induce nonneutralizing antibodies (Abs) with Fc-mediated functions in HIV-uninfected and HIV-infected subjects. Functional influenza-specific Ab responses were studied in 30 HIV-negative and 27 HIV......-positive subjects immunized against seasonal influenza. All 57 subjects received the 2015 TIV. Fc-mediated antihemagglutinin (anti-HA) Ab activity was measured in plasma before and 4 weeks after vaccination using Fc-receptor-binding assays, NK cell activation assays, and phagocytosis assays. At baseline, the HIV...

  17. Electronic, elastic and optical properties of divalent (R+2X) and trivalent (R+3X) rare earth monochalcogenides

    Science.gov (United States)

    Kumar, V.; Chandra, S.; Singh, J. K.

    2017-08-01

    Based on plasma oscillations theory of solids, simple relations have been proposed for the calculation of bond length, specific gravity, homopolar energy gap, heteropolar energy gap, average energy gap, crystal ionicity, bulk modulus, electronic polarizability and dielectric constant of rare earth divalent R+2X and trivalent R+3X monochalcogenides. The specific gravity of nine R+2X, twenty R+3X, and bulk modulus of twenty R+3X monochalcogenides have been calculated for the first time. The calculated values of all parameters are compared with the available experimental and the reported values. A fairly good agreement has been obtained between them. The average percentage deviation of two parameters: bulk modulus and electronic polarizability for which experimental data are known, have also been calculated and found to be better than the earlier correlations.

  18. Naturally occurring methyl salicylate glycosides.

    Science.gov (United States)

    Mao, Ping; Liu, Zizhen; Xie, Meng; Jiang, Rui; Liu, Weirui; Wang, Xiaohong; Meng, Shen; She, Gaimei

    2014-01-01

    As an important part of non steroids anti-inflammation drug (NSAIDs), salicylate has developed from natural substance salicylic acid to natrium salicylicum, to aspirin. Now, methyl salicylate glycoside, a new derivative of salicylic acid, is modified with a -COOH group integrated one methyl radical into formic ether, and a -OH linked with a monosaccharide, a disaccharide or a trisaccharide unit by glycosidic linkage. It has the similar pharmacological activities, anti-inflammatory, analgesic, antipyretic and antithrombotic as the previous salicylates' without resulting in serious side effects, particularly the gastrointestinal toxicity. Owing to the superiority of those significant bioactivities, methyl salicylate glycosides have became a hot research area in NSAIDs for several years. This paper compiles all 9 naturally occurring methyl salicylate glycosides, their distribution of the resource and pharmacological mechanism, which could contribute to the new drug discovery.

  19. Process for the production of methyl methacrylate

    NARCIS (Netherlands)

    Eastham, G.R.; Johnson, D.W.; Straathof, A.J.J.; Fraaije, Marco; Winter, Remko

    2015-01-01

    A process of producing methyl methacrylate or derivatives thereof is described. The process includes the steps of; (i) converting 2-butanone to methyl propionate using a Baeyer-Villiger monooxygenase, and (ii) treating the methyl propionate produced to obtain methyl methacrylate or derivatives

  20. Sorption competition of trivalent metals on corundum (α-Al{sub 2}O{sub 3}) studied on the macro- and microscopic scale

    Energy Technology Data Exchange (ETDEWEB)

    Virtanen, S.; Merilaeinen, S.; Lehto, J. [Helsinki Univ. (Finland); Eibl, Manuel; Huittinen, Nina [Helmholtz-Zentrum Dresden-Rossendorf e.V., Dresden (Germany). Surface Processes; Rossberg, Andre [Helmholtz-Zentrum Dresden-Rossendorf e.V., Dresden (Germany). Molecular Structures; Rabung, T. [Karlsruhe Institute of Technology (KIT), Karlsruhe (Germany)

    2017-06-01

    In this study we investigated the potential competitive influence of Y{sup 3+} on the uptake of trivalent lanthanides and actinides on corundum (α-Al{sub 2}O{sub 3}). Both batch sorption and time-resolved laser fluorescence spectroscopic (TRLFS) data showed a decreased uptake of Eu{sup 3+} or Cm{sup 3+}, respectively, in the presence of Y{sup 3+}, pointing toward sorption competition between the trivalent ions. A change in the actinide speciation on the corundum surface could be observed in the presence of Y{sup 3+}. In extended X-ray absorption fine structure (EXAFS) investigations, the speciation change could be attributed to a systematic transition from a tetradentate Am{sup 3+} surface complex to a tridentate one, when increasing the total metal ion concentration on the mineral surface.

  1. Mass Enhancement of Nearly Trivalent Compound EuCo2Si2: Studied by the de Haas-van Alphen Experiments and Energy Band Calculations

    International Nuclear Information System (INIS)

    Ōnuki, Yoshichika; Hedo, Masato; Nakama, Takao; Nakamura, Ai; Aoki, Dai; Boukahil, Mounir; Haga, Yoshinori; Takeuchi, Tetsuya; Harima, Hisatomo

    2015-01-01

    We succeeded in growing single crystals of EuCo 2 Si 2 by the Bridgman method, and carried out the de Haas-van Alphen (dHvA) experiments. EuCo 2 Si 2 was previously studied from a viewpoint of the trivalent electronic state on the basis of the magnetic susceptibility and X-ray absorption experiments, whereas most of the other Eu compounds order magnetically, with the divalent electronic state. The detected dHvA branches in the present experiments are found to be explained by the results of the full potential linearized augmented plane wave energy band calculations on the basis of a local density approximation (LDA) for YCo 2 Si 2 (LDA) and EuCo 2 Si 2 (LDA + U), revealing the trivalent electronic state. The detected cyclotron effective masses are moderately large, ranging from 1.2 to 2.9 m 0

  2. JAEA thermodynamic database for performance assessment of geological disposal of high-level and TRU wastes. Refinement of thermodynamic data for trivalent actinoids and samarium

    International Nuclear Information System (INIS)

    Kitamura, Akira; Fujiwara, Kenso; Yui, Mikazu

    2010-01-01

    Within the scope of the JAEA thermodynamic database project for performance assessment of geological disposal of high-level radioactive and TRU wastes, the refinement of the thermodynamic data for the inorganic compounds and complexes of trivalent actinoids (actinium(III), plutonium(III), americium(III) and curium(III)) and samarium(III) was carried out. Refinement of thermodynamic data for these elements was based on the thermodynamic database for americium published by the Nuclear Energy Agency in the Organisation for Economic Co-operation and Development (OECD/NEA). Based on the similarity of chemical properties among trivalent actinoids and samarium, complementary thermodynamic data for their species expected under the geological disposal conditions were selected to complete the thermodynamic data set for the performance assessment of geological disposal of radioactive wastes. (author)

  3. Molecular dynamics study of the coordination sphere of trivalent lanthanum in a highly concentrated LiCl aqueous solution: A combined classical and ab initio approach

    International Nuclear Information System (INIS)

    Vuilleumier, R.; Petit, L.; Maldivi, P.; Adamo, C.

    2008-01-01

    The first coordination sphere of trivalent lanthanum in a highly concentrated (14 M) lithium chloride solution is studied with a combination of classical molecular dynamics and density functional theory based first principle molecular dynamics. This method enables us to obtain a solvation shell of La 3+ containing 2 chloride ions and 6 water molecules. After refinement using first principle molecular dynamics, the resulting cation-water and cation-anion distances are in very good agreement with experiment. The 2 Cl - and the 6 water molecules arrange in a square anti-prism around La 3+ . Exchange of water molecules was also observed in the first-principle simulation, with an intermediate structure comprising 7 water molecules stable for 2.5 ps. Finally, evaluation of dipole moments using maximally localized Wannier functions shows a substantial polarization of the chloride anions and the water molecules in the first solvation shell of trivalent lanthanum. (authors)

  4. Trivalent pneumococcal protein recombinant vaccine protects against lethal Streptococcus pneumoniae pneumonia and correlates with phagocytosis by neutrophils during early pathogenesis.

    Science.gov (United States)

    Xu, Qingfu; Surendran, Naveen; Verhoeven, David; Klapa, Jessica; Ochs, Martina; Pichichero, Michael E

    2015-02-18

    Due to the fact that current polysaccharide-based pneumococcal vaccines have limited serotype coverage, protein-based vaccine candidates have been sought for over a decade to replace or complement current vaccines. We previously reported that a trivalent Pneumococcal Protein recombinant Vaccine (PPrV), showed protection against pneumonia and sepsis in an infant murine model. Here we investigated immunological correlates of protection of PPrV in the same model. C57BL/6J infant mice were intramuscularly vaccinated at age 1-3 weeks with 3 doses of PPrV, containing pneumococcal histidine triad protein D (PhtD), pneumococcal choline binding protein A (PcpA), and detoxified pneumolysin mutant PlyD1. 3-4 weeks after last vaccination, serum and lung antibody levels to PPrV components were measured, and mice were intranasally challenged with a lethal dose of Streptococcus pneumoniae (Spn) serotype 6A. Lung Spn bacterial burden, number of neutrophils and alveolar macrophages, phagocytosed Spn by granulocytes, and levels of cytokines and chemokines were determined at 6, 12, 24, and 48h after challenge. PPrV vaccination conferred 83% protection against Spn challenge. Vaccinated mice had significantly elevated serum and lung antibody levels to three PPrV components. In the first stage of pathogenesis of Spn induced pneumonia (6-24h after challenge), vaccinated mice had lower Spn bacterial lung burdens and more phagocytosed Spn in the granulocytes. PPrV vaccination led to lower levels of pro-inflammatory cytokines IL-6, IL-1β, and TFN-α, and other cytokines and chemokines (IL-12, IL-17, IFN-γ, MIP-1b, MIP-2 and KC, and G-CSF), presumably due to a lower lung bacterial burden. Trivalent PPrV vaccination results in increased serum and lung antibody levels to the vaccine components, a reduction in Spn induced lethality, enhanced early clearance of Spn in lungs due to more rapid and thorough phagocytosis of Spn by neutrophils, and correspondingly a reduction in lung inflammation

  5. Fermi Surface Properties of Eu-Divalent and Eu-Trivalent Electronic States with the AuCu3-type Cubic Structure

    International Nuclear Information System (INIS)

    Nakamura, Ai; Takeuchi, Tetsuya; Tatetsu, Yasutomi; Maehira, Takahiro; Hedo, Masato; Nakama, Takao; Ōnuki, Yoshichika; Harima, Hisatomo

    2015-01-01

    The electronic states in EuBi 3 and EuPd 3 are known to be Eu-divalent and Eu- trivalent, respectively, from the previous studies using polycrystal samples. In the present study, we succeeded in growing high-quality single crystals, and carried out the de Haas-van Alphen (dHvA) measurements and energy band calculations to clarify the Fermi surface properties

  6. Evaluation of the immunogenicity and protective effects of a trivalent chimeric norovirus P particle immunogen displaying influenza HA2 from subtypes H1, H3 and B.

    Science.gov (United States)

    Gong, Xin; Yin, He; Shi, Yuhua; He, Xiaoqiu; Yu, Yongjiao; Guan, Shanshan; Kuai, Ziyu; Haji, Nasteha M; Haji, Nafisa M; Kong, Wei; Shan, Yaming

    2016-05-25

    The ectodomain of the influenza A virus (IAV) hemagglutinin (HA) stem is highly conserved across strains and has shown promise as a universal influenza vaccine in a mouse model. In this study, potential B-cell epitopes were found through sequence alignment and epitope prediction in a stem fragment, HA2:90-105, which is highly conserved among virus subtypes H1, H3 and B. A norovirus (NoV) P particle platform was used to express the HA2:90-105 sequences from subtypes H1, H3 and B in loops 1, 2 and 3 of the protrusion (P) domain, respectively. Through mouse immunization and microneutralization assays, the immunogenicity and protective efficacy of the chimeric NoV P particle (trivalent HA2-PP) were tested against infection with three subtypes (H1N1, H3N2 and B) of IAV in Madin-Darby canine kidney cells. The protective efficacy of the trivalent HA2-PP was also evaluated preliminarily in vivo by virus challenge in the mouse model. The trivalent HA2-PP immunogen induced significant IgG antibody responses, which could be enhanced by a virus booster vaccination. Moreover, the trivalent HA2-PP immunogen also demonstrated in vitro neutralization of the H3 and B viruses, and in vivo protection against the H3 virus. Our results support the notion that a broadly protective vaccine approach using an HA2-based NoV P particle platform can provide cross-protection against challenge viruses of different IAV subtypes. The efficacy of the immunogen should be further enhanced for practicality, and a better understanding of the protective immune mechanism will be critical for the development of HA2-based multivalent vaccines.

  7. Quantifying benefits and risks of vaccinating Australian children aged six months to four years with trivalent inactivated seasonal influenza vaccine in 2010.

    Science.gov (United States)

    Kelly, H; Carcione, D; Dowse, G; Effler, P

    2010-09-16

    Australian and New Zealand health authorities identified seasonal trivalent inactivated influenza vaccines manufactured by CSL Biotherapies as the probable cause of increased febrile convulsions in children under five within 24 hours of vaccination and recommended against their use in this age group. We quantified the benefit-risk profile of the CSL vaccines using the number needed to vaccinate and suggest they might have caused two to three hospital admissions due to febrile convulsions for every hospital admission due to influenza prevented.

  8. Financial Support to Eligible Countries for the Switch From Trivalent to Bivalent Oral Polio Vaccine-Lessons Learned.

    Science.gov (United States)

    Shendale, Stephanie; Farrell, Margaret; Hampton, Lee M; Harris, Jennifer B; Kachra, Tasleem; Kurji, Feyrouz; Patel, Manish; Ramirez Gonzalez, Alejandro; Zipursky, Simona

    2017-07-01

    The global switch from trivalent oral polio vaccine (tOPV) to bivalent oral polio vaccine (bOPV) ("the switch") presented an unprecedented challenge to countries. In order to mitigate the risks associated with country-level delays in implementing the switch, the Global Polio Eradication Initiative provided catalytic financial support to specific countries for operational costs unique to the switch. Between November 2015 and February 2016, a total of approximately US$19.4 million in financial support was provided to 67 countries. On average, country budgets allocated 20% to human resources, 23% to trainings and meetings, 8% to communications and advocacy, 9% to logistics, 15% to monitoring, and 5% to waste management. All 67 funded countries successfully switched from tOPV to bOPV during April-May 2016. This funding provided target countries with the necessary catalytic support to facilitate the execution of the switch on an accelerated timeline, and the mechanism offers a model for similar support to future global health efforts, such as the eventual global withdrawal of bOPV. © The Author 2017. Published by Oxford University Press for the Infectious Diseases Society of America.

  9. Adsorption Mechanisms of Trivalent Gold onto Iron Oxy-Hydroxides: From the Molecular Scale to the Model

    International Nuclear Information System (INIS)

    Cances, Benjamin; Benedetti, Marc; Farges, Francois; Brown, Gordon E. Jr.

    2007-01-01

    Gold is a highly valuable metal that can concentrate in iron-rich exogenetic horizons such as laterites. An improved knowledge of the retention mechanisms of gold onto highly reactive soil components such as iron oxy-hydroxides is therefore needed to better understand and predict the geochemical behavior of this element. In this study, we use EXAFS information and titration experiments to provide a realistic thermochemical description of the sorption of trivalent gold onto iron oxy-hydroxides. Analysis of Au LIII-edge XAFS spectra shows that aqueous Au(III) adsorbs from chloride solutions onto goethite surfaces as inner-sphere square-planar complexes (Au(III)(OH,Cl)4), with dominantly OH ligands at pH > 6 and mixed OH/Cl ligands at lower pH values. In combination with these spectroscopic results, Reverse Monte Carlo simulations were used to constraint the possible sorption sites on the surface of goethite. Based on this structural information, we calculated sorption isotherms of Au(III) on Fe oxy-hydroxides surfaces, using the CD-MUSIC (Charge Distribution - MUlti SIte Complexation) model. The various Au(III)-sorbed species were identified as a function of pH, and the results of these EXAFS+CD-MUSIC models are compared with titration experiments. The overall good agreement between the predicted and measured structural models shows the potential of this combined approach to better model sorption processes of transition elements onto highly reactive solid surfaces such as goethite and ferrihydrite

  10. X-ray absorption spectroscopic study of trivalent and tetravalent actinides in solution at varying pH values

    Energy Technology Data Exchange (ETDEWEB)

    Brendebach, B.; Banik, N.L.; Marquardt, C.M.; Rothe, J.; Denecke, M.A.; Geckeis, H. [Forschungszentrum Karlsruhe (Germany). Inst. fuer Nukleare Entsorgung

    2009-07-01

    We perform X-ray absorption spectroscopy (XAS) investigations to monitor the stabilization of redox sensitive trivalent and tetravalent actinide ions in solution at acidic conditions in a pH range from 0 to 3 after treatment with holding reductants, hydroxylamine hydrochloride (NH{sub 2}OHHCl) and Rongalite (sodium hydroxymethanesulfinate, CH{sub 3}NaO{sub 3}S). X-ray absorption near edge structure (XANES) measurements clearly demonstrate the stability of the actinide species for several hours under the given experimental conditions. Hence, structural parameters can be accurately derived by extended X-ray absorption fine structure (EXAFS) investigations. The coordination structure of oxygen atoms belonging to water ligands surrounding the actinide ions does not change with increasing pH value (approximately 11 O atoms at 2.42 A in the case of U(IV) at pH 1, 9 0 atoms at 2.52 A for Np(III) at pH 1.5, and 10 O atoms at 2.49 A for Pu(III) up to pH 3), indicating that hydrolysis reactions are suppressed under the given chemical conditions. (orig.)

  11. A review of the demonstration of innovative solvent extraction processes for the recovery of trivalent minor actinides from PUREX raffinate

    International Nuclear Information System (INIS)

    Modolo, G.; Wilden, A.; Geist, A.; Magnusson, D.; Malmbeck, R.

    2012-01-01

    The selective partitioning (P) of long-lived minor actinides from highly active waste solutions and their transmutation (T) to short-lived or stable isotopes by nuclear reactions will reduce the long-term hazard of the high-level waste and significantly shorten the time needed to ensure their safe confinement in a repository. The present paper summarizes the on-going research activities at Forschungszentrum Juelich (FZJ), Karlsruher Institut fuer Technologie (KIT) and Institute for Transuranium Elements (ITU) in the field of actinide partitioning using innovative solvent extraction processes. European research over the last few decades, i.e. in the NEWPART, PARTNEW and EUROPART programmes, has resulted in the development of multi-cycle processes for minor actinide partitioning. These multi-cycle processes are based on the co-separation of trivalent actinides and lanthanides (e.g. by the DIAMEX process), followed by the subsequent actinide(III)/lanthanide(III) group separation in the SANEX process. The current direction of research for the development of innovative processes within the recent European ACSEPT project is discussed additionally. This paper is focused on the development of flow-sheets for recovery of americium and curium from highly active waste solutions. The flow-sheets are verified by demonstration processes, in centrifugal contactors, using synthetic or genuine fuel solutions. The feasibility of the processes is also discussed. (orig.)

  12. Local coordination and medium range order in molten trivalent metal chlorides: The role of screening by the chlorine component

    International Nuclear Information System (INIS)

    Pastore, G.; Tosi, M.P.

    1995-11-01

    Earlier work has identified the metal ion size R M as a relevant parameter in determining the evolution of the liquid structure of trivalent metal chlorides across the series from LaCl 3 (R M approx. 1.4 A) to AlCl 3 (R M approx. 0.8 A). Here we highlight the structural role of the chlorines by contrasting the structure of fully equilibrated melts with that of disordered systems obtained by quenching the chlorine component. Main attention is given to how the suppression of screening of the polyvalent ions by the chlorines changes trends in the local liquid structure (first neighbour coordination and partial radial distribution functions) and in the intermediate range order (first sharp diffraction peak in the partial structure factors). The main microscopic consequences of structural quenching of the chlorine component are a reduction in short range order and an enhancement of intermediate range order in the metal ion component, as well as the suppression of a tendency to molecular-type states at the lower end of the range of R M . (author). 23 refs, 6 figs

  13. Phase Transformation and Lattice Parameter Changes of Non-trivalent Rare Earth-Doped YSZ as a Function of Temperature

    Science.gov (United States)

    Jiang, Shengli; Huang, Xiao; He, Zhang; Buyers, Andrew

    2018-05-01

    To examine the effect of doping/co-doping on high-temperature phase compositions of YSZ, stand-alone YSZ and CeO2 and Nb2O5 co-doped YSZ samples were prepared using mechanical alloy and high-temperature sintering. XRD analysis was performed on these samples from room temperature to 1100 °C. The results show that the structure for the co-doped samples tends to be thermally stable when the test temperature is higher than a critical value. Monoclinic phase was dominant in Nb2O5 co-doped YSZ at temperatures lower than 600 °C, while for the YSZ and CeO2 co-doped YSZ, cubic/tetragonal phase was dominant in the whole test temperature range. The lattice parameters for all the samples increase with increasing test temperature generally. The lattice parameters for the two non-trivalent rare earth oxides co-doped YSZ show that the lattice parameter a for the cubic phase of the Ce4+ co-doped YSZ is consistently greater than that of 7YSZ which is related to the presence of larger radius of Ce4+ in the matrix. The lattice parameters a, b, c for the monoclinic phase of Ce4+ co-doped YSZ are much closer to each other than that of the Nb5+ co-doped YSZ, indicating the former has better tendency to form cubic/tetragonal phase, which is desired for vast engineering applications.

  14. Trivalent chromium removal from aqueous solutions by a sol–gel synthesized silica adsorbent functionalized with sulphonic acid groups

    Energy Technology Data Exchange (ETDEWEB)

    Gomez-Gonzalez, Sergio Efrain [Departamento de Ingeniería Química, Universidad de Guadalajara, Blvd. Marcelino García Barragán # 1421, esq. Calzada Olímpica, C.P. 44430 Guadalajara, Jalisco (Mexico); Carbajal-Arizaga, Gregorio Guadalupe [Departamento de Química, CUCEI, Universidad de Guadalajara, Blvd. Marcelino García Barragán # 1421, esq. Calzada Olímpica, C.P. 44430 Guadalajara, Jalisco (Mexico); Manriquez-Gonzalez, Ricardo [Departamento de Madera, Celulosa y Papel, CUCEI, Universidad de Guadalajara, Km 15.5, carretera Guadalajara-Nogales, Las Agujas, C.P. 45020 Zapopan, Jalisco (Mexico); De la Cruz-Hernandez, Wencel [Centro de Nanociencias y Nanotecnología, Universidad Nacional Autónoma de México, Km 107 carretera Tijuana-Ensenada, C.P. 22830 Ensenada, Baja California (Mexico); Gomez-Salazar, Sergio, E-mail: sergio.gomez@cucei.udg.mx [Departamento de Ingeniería Química, Universidad de Guadalajara, Blvd. Marcelino García Barragán # 1421, esq. Calzada Olímpica, C.P. 44430 Guadalajara, Jalisco (Mexico)

    2014-11-15

    Highlights: • Corpuscular sulphonic acid-functionalized silica holds improved uptake of chromium. • Mesopores on adsorbent facilitate (CH{sub 3}COO){sub 2}Cr{sup +} ion uptake on sulphonate sites. • Formation of chromium acetate sulphonate complex proposed from XPS results. • Fixed bed chromium uptake results suggest potential industrial use. - Abstract: A high capacity hybrid silica adsorbent was synthesized via sol–gel processing with sulphonic acid groups as trivalent chromium complex ions chelators from aqueous solutions. The synthesis included co-condensation of tetraethoxysilane (TEOS) with 3-(mercaptopropyl)trimethoxysilane (MPS), and oxidation of thiol to sulphonic acid groups. Chromium uptake kinetic, batch and fixed-bed experiments were performed to assess the removal of this metal from aqueous solutions. {sup 13}C, {sup 29}Si CPMAS NMR, FTIR, XPS were used to characterize the adsorbent structure and the nature of chromium complexes on the adsorbent surface. Chromium maximum uptake was obtained at pH 3 (72.8 mg/g). Elemental analysis results showed ligand density of 1.48 mmol sulphonic groups/g. About 407 mL of Cr(III) solution (311 mg/L) were treated to breakthrough point reaching ≤0.06 mg/L at the effluent. These results comply with USEPA regulation for chromium concentration in drinking water (≤0.1 mg/L). The adsorbent shows potential to be used in chromium separations to the industrial level.

  15. Thermoanalytical, spectroscopic and DFT studies of heavy trivalent lanthanides and yttrium(III) with oxamate as ligand

    Energy Technology Data Exchange (ETDEWEB)

    Caires, Flavio Junior; Gaglieri, Caroline, E-mail: caires.flavio@fc.unesp.br [Universidade Estadual Paulista Julio de Mesquita Filho (UNESP), Bauru, SP (Brazil). Faculdade de Ciencias; Nunes, Wilhan Donizete Goncalves; Nascimento, Andre Luiz Carneiro Soares do; Teixeira, Jose Augusto; Zangaro, Georgia Alvim Coelho; Treu-Filho, Oswaldo; Ionashiro, Massao [Universidade Estadual Paulista Julio de Mesquita Filho (UNESP), Araraquara, SP (Brazil)

    2017-07-15

    Solid-state LnL{sub 3}∙nH{sub 2}O complexes, where Ln stands for trivalent lanthanides (Tb to Lu) or yttrium(III) and L is oxamate (NH{sub 2}COCO{sub 2}{sup -}), have been synthesized. The characterization of the complexes was performed by using elemental analysis (EA), complexometric titration with EDTA, thermoanalytical techniques such as simultaneous thermogravimetry and differential scanning calorimetry (TG-DSC), evolved gas analysis (TG-FTIR), infrared spectroscopy (IR) and powder X-ray diffraction (XRPD). The results provided information about thermal behavior, crystallinity, stoichiometry, coordination sites, as well as the products released during thermal degradation of the complexes studied. Theoretical calculation of yttrium oxamate, as representative of all complexes was performed using density functional theory (DFT) for studying the molecular structure and vibrational spectrum of the investigated molecule in the ground state. The optimized geometrical parameters and theoretical vibrational spectrum obtained by DFT calculations are in good agreement with the experimental results. (author)

  16. Effect of buffer on the immune response to trivalent oral poliovirus vaccine in Bangladesh: a community based randomized controlled trial.

    Science.gov (United States)

    Chandir, Subhash; Ahamed, Kabir U; Baqui, Abdullah H; Sutter, Roland W; Okayasu, Hiromasa; Pallansch, Mark A; Oberste, Mark S; Moulton, Lawrence H; Halsey, Neal A

    2014-11-01

    Polio eradication efforts have been hampered by low responses to trivalent oral poliovirus vaccine (tOPV) in some developing countries. Since stomach acidity may neutralize vaccine viruses, we assessed whether administration of a buffer solution could improve the immunogenicity of tOPV. Healthy infants 4-6 weeks old in Sylhet, Bangladesh, were randomized to receive tOPV with or without a sodium bicarbonate and sodium citrate buffer at age 6, 10, and 14 weeks. Levels of serum neutralizing antibodies for poliovirus types 1, 2, and 3 were measured before and after vaccination, at 6 and 18 weeks of age, respectively. Serologic response rates following 3 doses of tOPV for buffer recipients and control infants were 95% and 88% (P=.065), respectively, for type 1 poliovirus; 95% and 97% (P=.543), respectively, for type 2 poliovirus; and 90% and 89% (P=.79), respectively, for type 3 poliovirus. Administration of a buffer solution prior to vaccination was not associated with statistically significant increases in the immune response to tOPV; however, a marginal 7% increase (P=.065) in serologic response to poliovirus type 1 was observed. NCT01579825. © The Author 2014. Published by Oxford University Press on behalf of the Infectious Diseases Society of America. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  17. Trivalent chromium removal from aqueous solutions by a sol–gel synthesized silica adsorbent functionalized with sulphonic acid groups

    International Nuclear Information System (INIS)

    Gomez-Gonzalez, Sergio Efrain; Carbajal-Arizaga, Gregorio Guadalupe; Manriquez-Gonzalez, Ricardo; De la Cruz-Hernandez, Wencel; Gomez-Salazar, Sergio

    2014-01-01

    Highlights: • Corpuscular sulphonic acid-functionalized silica holds improved uptake of chromium. • Mesopores on adsorbent facilitate (CH 3 COO) 2 Cr + ion uptake on sulphonate sites. • Formation of chromium acetate sulphonate complex proposed from XPS results. • Fixed bed chromium uptake results suggest potential industrial use. - Abstract: A high capacity hybrid silica adsorbent was synthesized via sol–gel processing with sulphonic acid groups as trivalent chromium complex ions chelators from aqueous solutions. The synthesis included co-condensation of tetraethoxysilane (TEOS) with 3-(mercaptopropyl)trimethoxysilane (MPS), and oxidation of thiol to sulphonic acid groups. Chromium uptake kinetic, batch and fixed-bed experiments were performed to assess the removal of this metal from aqueous solutions. 13 C, 29 Si CPMAS NMR, FTIR, XPS were used to characterize the adsorbent structure and the nature of chromium complexes on the adsorbent surface. Chromium maximum uptake was obtained at pH 3 (72.8 mg/g). Elemental analysis results showed ligand density of 1.48 mmol sulphonic groups/g. About 407 mL of Cr(III) solution (311 mg/L) were treated to breakthrough point reaching ≤0.06 mg/L at the effluent. These results comply with USEPA regulation for chromium concentration in drinking water (≤0.1 mg/L). The adsorbent shows potential to be used in chromium separations to the industrial level

  18. A chemiluminescence reagent free method for the determination of captopril in medicine and urine samples by using trivalent silver

    Directory of Open Access Journals (Sweden)

    Zhaofu Fu

    2017-08-01

    Full Text Available A novel flow-injection chemiluminescence (FI-CL method free of CL reagent was developed for the determination of captopril based on its enhancing effect on the CL derived from diperiodatoargentate(III-sulfuric acid system. Compared with the conventional CL system, the CL system based on trivalent silver was characterized of good selectivity for the absence of CL reagent. The CL mechanism was discussed through CL spectra and UV–vis absorption spectra. The conditions of the FI-CL system were investigated and optimized. Under the optimal conditions, the relative CL intensity was linear with the captopril concentration in the range of 0.3–15.0 μg/mL. The detection limit for captopril was 0.05 μg/mL, and the relative standard deviation (n=11 was 2.0% for 5.0 μg/mL captopril. The proposed method was applied to the analysis of captopril in tablet and human urine with the recoveries of 83.1%–112.5%, and the relative standard deviations of 0.5%–4.4%. The results obtained by the proposed method agreed well with those obtained from HPLC method. The proposed method is fast, convenient, and cost-effective for the determination of captopril in medicine and biological samples.

  19. Histone Lysine Methylation and Neurodevelopmental Disorders

    Directory of Open Access Journals (Sweden)

    Jeong-Hoon Kim

    2017-06-01

    Full Text Available Methylation of several lysine residues of histones is a crucial mechanism for relatively long-term regulation of genomic activity. Recent molecular biological studies have demonstrated that the function of histone methylation is more diverse and complex than previously thought. Moreover, studies using newly available genomics techniques, such as exome sequencing, have identified an increasing number of histone lysine methylation-related genes as intellectual disability-associated genes, which highlights the importance of accurate control of histone methylation during neurogenesis. However, given the functional diversity and complexity of histone methylation within the cell, the study of the molecular basis of histone methylation-related neurodevelopmental disorders is currently still in its infancy. Here, we review the latest studies that revealed the pathological implications of alterations in histone methylation status in the context of various neurodevelopmental disorders and propose possible therapeutic application of epigenetic compounds regulating histone methylation status for the treatment of these diseases.

  20. miRNAting control of DNA methylation

    Indian Academy of Sciences (India)

    miRNAting control of DNA methylation. ASHWANI ... function and biological process ... Enrichment analysis of the genes methylated by DRM2 for molecular function and biological ... 39(3), June 2014, 365–380, © Indian Academy of Sciences.

  1. Bacterial production of methyl ketones

    Energy Technology Data Exchange (ETDEWEB)

    Beller, Harry R.; Goh, Ee-Been

    2017-01-31

    The present invention relates to methods and compositions for increasing production of methyl ketones in a genetically modified host cell that overproduces .beta.-ketoacyl-CoAs through a re-engineered .beta.-oxidation pathway and overexpresses FadM.

  2. Electronic transport in methylated fragments of DNA

    International Nuclear Information System (INIS)

    Almeida, M. L. de; Oliveira, J. I. N.; Lima Neto, J. X.; Gomes, C. E. M.; Fulco, U. L.; Albuquerque, E. L.; Freire, V. N.; Caetano, E. W. S.; Moura, F. A. B. F. de; Lyra, M. L.

    2015-01-01

    We investigate the electronic transport properties of methylated deoxyribonucleic-acid (DNA) strands, a biological system in which methyl groups are added to DNA (a major epigenetic modification in gene expression), sandwiched between two metallic platinum electrodes. Our theoretical simulations apply an effective Hamiltonian based on a tight-binding model to obtain current-voltage curves related to the non-methylated/methylated DNA strands. The results suggest potential applications in the development of novel biosensors for molecular diagnostics

  3. Electronic transport in methylated fragments of DNA

    Energy Technology Data Exchange (ETDEWEB)

    Almeida, M. L. de; Oliveira, J. I. N.; Lima Neto, J. X.; Gomes, C. E. M.; Fulco, U. L., E-mail: umbertofulco@gmail.com; Albuquerque, E. L. [Departamento de Biofísica e Farmacologia, Universidade Federal do Rio Grande do Norte, 59072-970 Natal-RN (Brazil); Freire, V. N. [Departamento de Física, Universidade Federal do Ceará, 60455-760 Fortaleza, CE (Brazil); Caetano, E. W. S. [Instituto Federal de Educação, Ciência e Tecnologia do Ceará, 60040-531 Fortaleza, CE (Brazil); Moura, F. A. B. F. de; Lyra, M. L. [Instituto de Física, Universidade Federal de Alagoas, 57072-900 Maceió-AL (Brazil)

    2015-11-16

    We investigate the electronic transport properties of methylated deoxyribonucleic-acid (DNA) strands, a biological system in which methyl groups are added to DNA (a major epigenetic modification in gene expression), sandwiched between two metallic platinum electrodes. Our theoretical simulations apply an effective Hamiltonian based on a tight-binding model to obtain current-voltage curves related to the non-methylated/methylated DNA strands. The results suggest potential applications in the development of novel biosensors for molecular diagnostics.

  4. Methylation sensitive amplified polymorphism (MSAP) reveals that ...

    African Journals Online (AJOL)

    ajl yemi

    2011-12-19

    Dec 19, 2011 ... Key words: Salt stress, alkali stress, Gossypium hirsutum L., DNA methylation, methylation sensitive amplified polymorphism (MSAP). INTRODUCTION. DNA methylation is one of the key epigenetic mecha- nisms among eukaryotes that can modulate gene expression without the changes of DNA sequence.

  5. miRNAting control of DNA methylation

    Indian Academy of Sciences (India)

    DNA methylation is a type of epigenetic modification where a methyl group is added to the cytosine or adenine residue of a given DNA sequence. It has been observed that DNA methylation is achieved by some collaborative agglomeration of certain proteins and non-coding RNAs. The assembly of IDN2 and its ...

  6. Identification of endometrial cancer methylation features using combined methylation analysis methods.

    Directory of Open Access Journals (Sweden)

    Michael P Trimarchi

    Full Text Available DNA methylation is a stable epigenetic mark that is frequently altered in tumors. DNA methylation features are attractive biomarkers for disease states given the stability of DNA methylation in living cells and in biologic specimens typically available for analysis. Widespread accumulation of methylation in regulatory elements in some cancers (specifically the CpG island methylator phenotype, CIMP can play an important role in tumorigenesis. High resolution assessment of CIMP for the entire genome, however, remains cost prohibitive and requires quantities of DNA not available for many tissue samples of interest. Genome-wide scans of methylation have been undertaken for large numbers of tumors, and higher resolution analyses for a limited number of cancer specimens. Methods for analyzing such large datasets and integrating findings from different studies continue to evolve. An approach for comparison of findings from a genome-wide assessment of the methylated component of tumor DNA and more widely applied methylation scans was developed.Methylomes for 76 primary endometrial cancer and 12 normal endometrial samples were generated using methylated fragment capture and second generation sequencing, MethylCap-seq. Publically available Infinium HumanMethylation 450 data from The Cancer Genome Atlas (TCGA were compared to MethylCap-seq data.Analysis of methylation in promoter CpG islands (CGIs identified a subset of tumors with a methylator phenotype. We used a two-stage approach to develop a 13-region methylation signature associated with a "hypermethylator state." High level methylation for the 13-region methylation signatures was associated with mismatch repair deficiency, high mutation rate, and low somatic copy number alteration in the TCGA test set. In addition, the signature devised showed good agreement with previously described methylation clusters devised by TCGA.We identified a methylation signature for a "hypermethylator phenotype" in

  7. MethylMix 2.0: an R package for identifying DNA methylation genes.

    Science.gov (United States)

    Cedoz, Pierre-Louis; Prunello, Marcos; Brennan, Kevin; Gevaert, Olivier

    2018-04-14

    DNA methylation is an important mechanism regulating gene transcription, and its role in carcinogenesis has been extensively studied. Hyper and hypomethylation of genes is a major mechanism of gene expression deregulation in a wide range of diseases. At the same time, high-throughput DNA methylation assays have been developed generating vast amounts of genome wide DNA methylation measurements. We developed MethylMix, an algorithm implemented in R to identify disease specific hyper and hypomethylated genes. Here we present a new version of MethylMix that automates the construction of DNA-methylation and gene expression datasets from The Cancer Genome Atlas (TCGA). More precisely, MethylMix 2.0 incorporates two major updates: the automated downloading of DNA methylation and gene expression datasets from TCGA and the automated preprocessing of such datasets: value imputation, batch correction and CpG sites clustering within each gene. The resulting datasets can subsequently be analyzed with MethylMix to identify transcriptionally predictive methylation states. We show that the Differential Methylation Values created by MethylMix can be used for cancer subtyping. olivier.gevaert@stanford.edu. https://bioconductor.org/packages/release/bioc/manuals/MethylMix/man/MethylMix.pdf. MethylMix 2.0 was implemented as an R package and is available in bioconductor.

  8. Avocado and olive oil methyl esters

    International Nuclear Information System (INIS)

    Knothe, Gerhard

    2013-01-01

    Biodiesel, the mono-alkyl esters of vegetable oils, animal fats or other triacylglycerol-containing materials and an alternative to conventional petroleum-based diesel fuel, has been derived from a variety of feedstocks. Numerous feedstocks have been investigated as potential biodiesel sources, including commodity oils, however, the methyl esters of avocado and olive oil would likely be suitable as biodiesel fuel. In order to expand the database and comprehensive evaluation of the properties of vegetable oil esters, in this work the fuel-related properties of avocado and olive oil methyl esters, which exhibit similar fatty acid profiles including high oleic acid content, are determined. The cetane numbers of avocado oil methyl esters and olive oil methyl esters are relatively high, determined as 59.2 and 62.5, respectively, due to their elevated content of methyl oleate. Other properties are well within the ranges specified in biodiesel standards. The cloud points of both esters are slightly above 0 °C due to their content of saturated esters, especially methyl palmitate. Overall, avocado and olive oil yield methyl esters with fuel properties comparable to methyl esters from other commodity vegetable oils. The 1 H and 13 C NMR spectra of avocado and olive oil methyl esters are reported. -- Highlights: • Methyl esters of avocado and olive oil meet biodiesel fuel standards. • Provides comparison for methyl esters of other vegetable oils with high oleic content. • Discusses and compares present results with prior literature

  9. Methylated genes as new cancer biomarkers.

    LENUS (Irish Health Repository)

    Duffy, M J

    2012-02-01

    Aberrant hypermethylation of promoter regions in specific genes is a key event in the formation and progression of cancer. In at least some situations, these aberrant alterations occur early in the formation of malignancy and appear to be tumour specific. Multiple reports have suggested that measurement of the methylation status of the promoter regions of specific genes can aid early detection of cancer, determine prognosis and predict therapy responses. Promising DNA methylation biomarkers include the use of methylated GSTP1 for aiding the early diagnosis of prostate cancer, methylated PITX2 for predicting outcome in lymph node-negative breast cancer patients and methylated MGMT in predicting benefit from alkylating agents in patients with glioblastomas. However, prior to clinical utilisation, these findings require validation in prospective clinical studies. Furthermore, assays for measuring gene methylation need to be standardised, simplified and evaluated in external quality assurance programmes. It is concluded that methylated genes have the potential to provide a new generation of cancer biomarkers.

  10. Methyl mercury in terrestrial compartments

    International Nuclear Information System (INIS)

    Stoeppler, M.; Burow, M.; Padberg, S.; May, K.

    1993-09-01

    On the basis of the analytical methodology available at present the state of the art for the determination of total mercury and of various organometallic compounds of mercury in air, precipitation, limnic systems, soils, plants and biota is reviewed. This is followed by the presentation and discussion of examples for the data obtained hitherto for trace and ultratrace levels of total mercury and mainly methyl mercury in terrestrial and limnic environments as well as in biota. The data discussed stem predominantly from the past decade in which, due to significant methodological progress, many new aspects were elucidated. They include the most important results in this area achieved by the Research Centre (KFA) Juelich within the project 'Origin and Fate of Methyl Mercury' (contracts EV4V-0138-D and STEP-CT90-0057) supported by the Commission of the European Communities, Brussels. (orig.) [de

  11. Uptake and Effectiveness of a Trivalent Inactivated Influenza Vaccine in Children in Urban and Rural Kenya, 2010 to 2012.

    Science.gov (United States)

    Katz, Mark A; Lebo, Emmaculate; Emukule, Gideon O; Otieno, Nancy; Caselton, Deborah L; Bigogo, Godfrey; Njuguna, Henry; Muthoka, Philip M; Waiboci, Lilian W; Widdowson, Marc-Alain; Xu, Xiyan; Njenga, Moses K; Mott, Joshua A; Breiman, Robert F

    2016-03-01

    In Africa, recent surveillance has demonstrated a high burden of influenza, but influenza vaccine is rarely used. In Kenya, a country with a tropical climate, influenza has been shown to circulate year-round, like in other tropical countries. During 3 months in 2010 and 2011 and 2 months in 2012, the Kenya Medical Research Institute/Centers for Disease Control and Prevention-Kenya offered free injectable trivalent inactivated influenza vaccine to children 6 months to 10 years old in 2 resource-poor communities in Kenya-Kibera and Lwak (total population ~50,000). We conducted a case-control study to evaluate vaccine effectiveness (VE) in preventing laboratory-confirmed influenza associated with influenza-like illness and acute lower respiratory illness. Of the approximately 18,000 eligible children, 41%, 48% and 51% received at least 1 vaccine in 2010, 2011 and 2012, respectively; 30%, 36% and 38% were fully vaccinated. VE among fully vaccinated children was 57% [95% confidence interval (CI): 29% to 74%] during a 6-month follow-up period, 39% (95% CI: 17% to 56%) during a 9-month follow-up period and 48% (95% CI: 32% to 61%) during a 12-month follow-up period. For the 12-month follow-up period, VE was statistically significant in children Kenya, parents of nearly half of the eligible children <10 years old chose to get their children vaccinated with a free influenza vaccine. During a 12-month follow-up period, the vaccine was moderately effective in preventing medically attended influenza-associated respiratory illness.

  12. Organic-inorganic perovskites containing trivalent metal halide layers: the templating influence of the organic cation layer.

    Science.gov (United States)

    Mitzi, D B

    2000-12-25

    Thin sheetlike crystals of the metal-deficient perovskites (H2AEQT)M2/3I4 [M = Bi or Sb; AEQT = 5,5"'-bis-(aminoethyl)-2,2':5',2'':5'',2'''-quaterthiophene] were formed from slowly cooled ethylene glycol/2-butanol solutions containing the bismuth(III) or antimony(III) iodide and AEQT.2HI salts. Each structure was refined in a monoclinic (C2/m) subcell, with the lattice parameters a = 39.712(13) A, b = 5.976(2) A, c = 6.043(2) A, beta = 92.238(5) degrees, and Z = 2 for M = Bi and a = 39.439(7) A, b = 5.952(1) A, c = 6.031(1) A, beta = 92.245(3) degrees, and Z = 2 for M = Sb. The trivalent metal cations locally adopt a distorted octahedral coordination, with M-I bond lengths ranging from 3.046(1) to 3.218(3) A (3.114 A average) for M = Bi and 3.012(1) to 3.153(2) A (3.073 A average) for M = Sb. The new organic-inorganic hybrids are the first members of a metal-deficient perovskite family consisting of (Mn+)2/nV(n-2)/nX4(2-) sheets, where V represents a vacancy (generally left out of the formula) and the metal cation valence, n, is greater than 2. The organic layers in the AEQT-based organic-inorganic hybrids feature edge-to-face aromatic interactions among the rigid, rodlike quaterthiophene moieties, which may help to stabilize the unusual metal-deficient layered structures.

  13. Efficient red organic electroluminescent devices based on trivalent europium complex obtained by designing the device structure with stepwise energy levels

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Liang; Jiang, Yunlong; Cui, Rongzhen; Li, Yanan; Zhao, Xuesen; Deng, Ruiping; Zhang, Hongjie, E-mail: hongjie@ciac.ac.cn

    2016-02-15

    In this study, we aim to further enhance the electroluminescence (EL) performances of trivalent europium complex Eu(TTA){sub 3}phen (TTA=thenoyltrifluoroacetone and phen=1,10-phenanthroline) by designing the device structure with stepwise energy levels. The widely used bipolar material 2,6-bis(3-(9H-carbazol-9-yl)phenyl)pyridine (26DCzPPy) was chosen as host material, while the doping concentration of Eu(TTA){sub 3}phen was optimized to be 4%. To facilitate the injection and transport of holes, MoO{sub 3} anode modification layer and 4,4′,4′′-Tris(carbazole-9-yl)triphenylamine (TcTa) hole transport layer were inserted in sequence. Efficient pure red emission with suppressed efficiency roll-off was obtained attributed to the reduction of accumulation holes, the broadening of recombination zone, and the improved balance of holes and electrons on Eu(TTA){sub 3}phen molecules. Finally, the device with 3 nm MoO{sub 3} and 5 nm TcTa obtained the highest brightness of 3278 cd/m{sup 2}, current efficiency of 12.45 cd/A, power efficiency of 11.50 lm/W, and external quantum efficiency of 6.60%. Such a device design strategy helps to improve the EL performances of emitters with low-lying energy levels and provides a chance to simplify device fabrication processes. - Highlights: • Electroluminescent performances of europium complex were further improved. • Device structure with stepwise energy levels was designed. • Better carriers' balance was realized by improving the injection and transport of holes. • The selection of bipolar host caused the broadening of recombination zone.

  14. Interactive effect of trivalent iron on activated sludge digestion and biofilm structure in attached growth reactor of waste tire rubber.

    Science.gov (United States)

    Sharafat, Iqra; Saeed, Dania Khalid; Yasmin, Sumera; Imran, Asma; Zafar, Zargona; Hameed, Abdul; Ali, Naeem

    2018-01-01

    Waste tire rubber (WTR) has been introduced as an alternative, novel media for biofilm development in several experimental systems including attached growth bioreactors. In this context, four laboratory-scale static batch bioreactors containing WTR as a support material for biofilm development were run under anoxic condition for 90 days using waste activated sludge as an inoculum under the influence of different concentrations (2.5, 6.5, 8.5 mg/l) of trivalent ferric iron (Fe 3+ ). The data revealed that activated sludge with a Fe 3+ concentration of 8.5 mg/l supported the maximum bacterial biomass [4.73E + 10 CFU/ml cm 2 ]; besides, it removed 38% more Chemical oxygen demand compared to Fe 3+ free condition from the reactor. Biochemical testing and 16S rDNA phylogenetic analysis of WTR-derived biofilm communities further suggested the role of varying concentrations of Fe 3+ on the density and diversity of members of Enterobacteria(ceae), ammonium (AOB) and nitrite oxidizing bacteria. Furthermore, Fluorescent in situ hybridization with phylogenetic oligonucleotide probes and confocal laser scanning microscopy of WTR biofilms indicated a significant increase in density of eubacteria (3.00E + 01 to.05E + 02 cells/cm 2 ) and beta proteobacteria (8.10E + 01 to 1.42E + 02 cells/cm 2 ), respectively, with an increase in Fe 3+ concentration in the reactors, whereas, the cell density of gamma proteobacteria in biofilms decreased.

  15. The effectiveness of seasonal trivalent inactivated influenza vaccine in preventing laboratory confirmed influenza hospitalisations in Auckland, New Zealand in 2012.

    Science.gov (United States)

    Turner, Nikki; Pierse, Nevil; Bissielo, Ange; Huang, Q Sue; Baker, Michael G; Widdowson, Marc-Alain; Kelly, Heath

    2014-06-17

    Few studies report the effectiveness of trivalent inactivated influenza vaccine (TIV) in preventing hospitalisation for influenza-confirmed respiratory infections. Using a prospective surveillance platform, this study reports the first such estimate from a well-defined ethnically diverse population in New Zealand (NZ). A case test-negative design was used to estimate propensity adjusted vaccine effectiveness. Patients with a severe acute respiratory infection (SARI), defined as a patient of any age requiring hospitalisation with a history of a fever or a measured temperature ≥38°C and cough and onset within the past 7 days, admitted to public hospitals in South and Central Auckland were eligible for inclusion in the study. Cases were SARI patients who tested positive for influenza, while non-cases (controls) were SARI patients who tested negative. Results were adjusted for the propensity to be vaccinated and the timing of the influenza season. The propensity and season adjusted vaccine effectiveness (VE) was estimated as 39% (95% CI 16;56). The VE point estimate against influenza A (H1N1) was lower than for influenza B or influenza A (H3N2) but confidence intervals were wide and overlapping. Estimated VE was 59% (95% CI 26;77) in patients aged 45-64 years but only 8% (-78;53) in those aged 65 years and above. Prospective surveillance for SARI has been successfully established in NZ. This study for the first year, the 2012 influenza season, has shown low to moderate protection by TIV against influenza positive hospitalisation. Copyright © 2014 Elsevier Ltd. All rights reserved.

  16. The effectiveness of seasonal trivalent inactivated influenza vaccine in preventing laboratory confirmed influenza hospitalisations in Auckland, New Zealand in 2012

    Science.gov (United States)

    Turner, Nikki; Pierse, Nevil; Bissielo, Ange; Huang, Q Sue; Baker, Michael; Widdowson, Marc-Alain; Kelly, Heath

    2015-01-01

    Background Few studies report the effectiveness of trivalent inactivated influenza vaccine (TIV) in preventing hospitalisation for influenza-confirmed respiratory infections. Using a prospective surveillance platform, this study reports the first such estimate from a well-defined ethnically diverse population in New Zealand (NZ). Methods A case test-negative study was used to estimate propensity adjusted vaccine effectiveness. Patients with a severe acute respiratory infection (SARI), defined as a patient of any age requiring hospitalization with a history of a fever or a measured temperature ≥38°C and cough and onset within the past 7 days, admitted to public hospitals in Central, South and East Auckland were eligible for inclusion in the study. Cases were SARI patients who tested positive for influenza, while non-cases (controls) were SARI patients who tested negative. Results were adjusted for the propensity to be vaccinated and the timing of the influenza season Results The propensity and season adjusted vaccine effectiveness (VE) was estimated as 37% (95% CI 18;51). The VE point estimate against influenza A (H1N1) was higher than for influenza B or influenza A (H3N2) but confidence intervals were wide and overlapping. Estimated VE was 51% (95% CI 28;67) in patients aged 18-64 years but only 6% (95% CI -51;42) in those aged 65 years and above. Conclusion Prospective surveillance for SARI has been successfully established in NZ . This study for the first year, the 2012 influenza season, has shown low to moderate protection by TIV against hospitalisation for laboratory-confirmed influenza. PMID:24768730

  17. Thermophysical study of methyl levulinate

    International Nuclear Information System (INIS)

    Lomba, Laura; Lafuente, Carlos; García-Mardones, Mónica; Gascón, Ignacio; Giner, Beatriz

    2013-01-01

    Highlights: • We have carried out a thermophysical characterization of methyl levulinate. • The study has been performed over a temperature range from (278.15 to 328.15) K. • pρT behavior has been studied over a temperature range from (333.15 to 453.15) K. • TRIDEN equation has been used to correlate pρT data. • Results have been compared with of ethyl and butyl levulinate and levulinic acid. -- Abstract: Several thermophysical properties (density, speed of sound, refractive index, surface tension, static permittivity and dynamic viscosity) of methyl levulinate have been measured under atmospheric pressure at temperatures from (278.15 to 338.15) K, while the vapor pressure was determined over a temperature range from (333.15 to 453.15) K. Furthermore, pρT behavior has been also investigated using a high-pressure, high-temperature vibrating tube densimeter over a temperature range from (283.15 to 338.15) K and a pressure range from (0.1 to 60.0) MPa. All these values obtained for methyl levulinate have been compared with other members of the levulinate family and also with levulinic acid

  18. Evolution of DNA Methylation across Insects.

    Science.gov (United States)

    Bewick, Adam J; Vogel, Kevin J; Moore, Allen J; Schmitz, Robert J

    2017-03-01

    DNA methylation contributes to gene and transcriptional regulation in eukaryotes, and therefore has been hypothesized to facilitate the evolution of plastic traits such as sociality in insects. However, DNA methylation is sparsely studied in insects. Therefore, we documented patterns of DNA methylation across a wide diversity of insects. We predicted that underlying enzymatic machinery is concordant with patterns of DNA methylation. Finally, given the suggestion that DNA methylation facilitated social evolution in Hymenoptera, we tested the hypothesis that the DNA methylation system will be associated with presence/absence of sociality among other insect orders. We found DNA methylation to be widespread, detected in all orders examined except Diptera (flies). Whole genome bisulfite sequencing showed that orders differed in levels of DNA methylation. Hymenopteran (ants, bees, wasps and sawflies) had some of the lowest levels, including several potential losses. Blattodea (cockroaches and termites) show all possible patterns, including a potential loss of DNA methylation in a eusocial species whereas solitary species had the highest levels. Species with DNA methylation do not always possess the typical enzymatic machinery. We identified a gene duplication event in the maintenance DNA methyltransferase 1 (DNMT1) that is shared by some Hymenoptera, and paralogs have experienced divergent, nonneutral evolution. This diversity and nonneutral evolution of underlying machinery suggests alternative DNA methylation pathways may exist. Phylogenetically corrected comparisons revealed no evidence that supports evolutionary association between sociality and DNA methylation. Future functional studies will be required to advance our understanding of DNA methylation in insects. © The Author 2016. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

  19. Systemic effects of chronically administered methyl prednisolonate and methyl 17-deoxyprednisolonate.

    Science.gov (United States)

    Olejniczak, E; Lee, H J

    1984-06-01

    The systemic activities of methyl prednisolonate and methyl 17-deoxyprednisolonate (1) were studied in rats. Methyl 17-deoxyprednisolonate produced significant changes in the amount of sodium ion (decreased) and potassium ion (increased) in urine; however, methyl prednisolonate had no effect on electrolyte balance. Both methyl prednisolonate and methyl 17-deoxyprednisolonate had no effect on liver glycogen content, plasma corticosterone level and relative adrenal weight. In contrast, the parent compound prednisolone caused a significant decrease in liver glycogen content, plasma corticosterone level and relative adrenal weight.

  20. Efficacy of a Trivalent Hand, Foot, and Mouth Disease Vaccine against Enterovirus 71 and Coxsackieviruses A16 and A6 in Mice

    Directory of Open Access Journals (Sweden)

    Elizabeth A. Caine

    2015-11-01

    Full Text Available Hand, foot, and mouth disease (HFMD has recently emerged as a major public health concern across the Asian-Pacific region. Enterovirus 71 (EV71 and Coxsackievirus A16 (CVA16 are the primary causative agents of HFMD, but other members of the Enterovirus A species, including Coxsackievirus A6 (CVA6, can cause disease. The lack of small animal models for these viruses have hampered the development of a licensed HFMD vaccine or antivirals. We have previously reported on the development of a mouse model for EV71 and demonstrated the protective efficacy of an inactivated EV71 vaccine candidate. Here, mouse-adapted strains of CVA16 and CVA6 were produced by sequential passage of the viruses through mice deficient in interferon (IFN α/β (A129 and α/β and γ (AG129 receptors. Adapted viruses were capable of infecting 3 week-old A129 (CVA6 and 12 week-old AG129 (CVA16 mice. Accordingly, these models were used in active and passive immunization studies to test the efficacy of a trivalent vaccine candidate containing inactivated EV71, CVA16, and CVA6. Full protection from lethal challenge against EV71 and CVA16 was observed in trivalent vaccinated groups. In contrast, monovalent vaccinated groups with non-homologous challenges failed to cross protect. Protection from CVA6 challenge was accomplished through a passive transfer study involving serum raised against the trivalent vaccine. These animal models will be useful for future studies on HFMD related pathogenesis and the efficacy of vaccine candidates.

  1. Efficacy of a Trivalent Hand, Foot, and Mouth Disease Vaccine against Enterovirus 71 and Coxsackieviruses A16 and A6 in Mice.

    Science.gov (United States)

    Caine, Elizabeth A; Fuchs, Jeremy; Das, Subash C; Partidos, Charalambos D; Osorio, Jorge E

    2015-11-17

    Hand, foot, and mouth disease (HFMD) has recently emerged as a major public health concern across the Asian-Pacific region. Enterovirus 71 (EV71) and Coxsackievirus A16 (CVA16) are the primary causative agents of HFMD, but other members of the Enterovirus A species, including Coxsackievirus A6 (CVA6), can cause disease. The lack of small animal models for these viruses have hampered the development of a licensed HFMD vaccine or antivirals. We have previously reported on the development of a mouse model for EV71 and demonstrated the protective efficacy of an inactivated EV71 vaccine candidate. Here, mouse-adapted strains of CVA16 and CVA6 were produced by sequential passage of the viruses through mice deficient in interferon (IFN) α/β (A129) and α/β and γ (AG129) receptors. Adapted viruses were capable of infecting 3 week-old A129 (CVA6) and 12 week-old AG129 (CVA16) mice. Accordingly, these models were used in active and passive immunization studies to test the efficacy of a trivalent vaccine candidate containing inactivated EV71, CVA16, and CVA6. Full protection from lethal challenge against EV71 and CVA16 was observed in trivalent vaccinated groups. In contrast, monovalent vaccinated groups with non-homologous challenges failed to cross protect. Protection from CVA6 challenge was accomplished through a passive transfer study involving serum raised against the trivalent vaccine. These animal models will be useful for future studies on HFMD related pathogenesis and the efficacy of vaccine candidates.

  2. Compatibility of a bivalent modified-live vaccine against Bordetella bronchiseptica and CPiV, and a trivalent modified-live vaccine against CPV, CDV and CAV-2.

    Science.gov (United States)

    Jacobs, A A C; Bergman, J G H E; Theelen, R P H; Jaspers, R; Helps, J M; Horspool, L J I; Paul, G

    2007-01-13

    Eight puppies (group 1) were vaccinated once with a bivalent modified-live vaccine against infectious tracheobronchitis by the intranasal route and at the same time with an injectable trivalent vaccine against canine parvovirus, canine distemper virus and canine adenovirus; a second group of eight puppies (group 2) was vaccinated only with the intranasal bivalent vaccine, and a further eight puppies (group 3) were vaccinated only with the injectable trivalent vaccine. Three weeks later they were all challenged with wildtype Bordetella bronchiseptica and canine parainfluenza virus by the aerosol route, and their antibody responses to the five vaccine organisms were determined. Oronasal swabs were taken regularly before and after the challenge for the isolation of bacteria and viruses, and the puppies were observed for clinical signs for three weeks after the challenge. There were no significant differences in the puppies' titres against canine parvovirus, canine distemper virus and canine adenovirus type 2 between the groups vaccinated with or without the bivalent intranasal vaccine. After the challenge the mean clinical scores of the two groups vaccinated with the intranasal vaccine were nearly 90 per cent lower (P=0.001) than the mean score of the group vaccinated with only the trivalent injectable vaccine, and the puppies in this group all became culture-positive for B bronchiseptica and canine parainfluenza virus. There were only small differences between the rates of isolation of B bronchiseptica from groups 1, 2 and 3, but significantly lower yields of canine parainfluenza virus were isolated from groups 1 and 2 than from group 3.

  3. Methylation patterns in marginal zone lymphoma.

    Science.gov (United States)

    Arribas, Alberto J; Bertoni, Francesco

    Promoter DNA methylation is a major regulator of gene expression and transcription. The identification of methylation changes is important for understanding disease pathogenesis, for identifying prognostic markers and can drive novel therapeutic approaches. In this review we summarize the current knowledge regarding DNA methylation in MALT lymphoma, splenic marginal zone lymphoma, nodal marginal zone lymphoma. Despite important differences in the study design for different publications and the existence of a sole large and genome-wide methylation study for splenic marginal zone lymphoma, it is clear that DNA methylation plays an important role in marginal zone lymphomas, in which it contributes to the inactivation of tumor suppressors but also to the expression of genes sustaining tumor cell survival and proliferation. Existing preclinical data provide the rationale to target the methylation machinery in these disorders. Copyright © 2016 Elsevier Ltd. All rights reserved.

  4. Wp specific methylation of highly proliferated LCLs

    International Nuclear Information System (INIS)

    Park, Jung-Hoon; Jeon, Jae-Pil; Shim, Sung-Mi; Nam, Hye-Young; Kim, Joon-Woo; Han, Bok-Ghee; Lee, Suman

    2007-01-01

    The epigenetic regulation of viral genes may be important for the life cycle of EBV. We determined the methylation status of three viral promoters (Wp, Cp, Qp) from EBV B-lymphoblastoid cell lines (LCLs) by pyrosequencing. Our pyrosequencing data showed that the CpG region of Wp was methylated, but the others were not. Interestingly, Wp methylation was increased with proliferation of LCLs. Wp methylation was as high as 74.9% in late-passage LCLs, but 25.6% in early-passage LCLs. From two Burkitt's lymphoma cell lines, Wp specific hypermethylation was also found (>80%). Interestingly, the expression of EBNA2 gene which located directly next to Wp was associated with its methylation. Our data suggested that Wp specific methylation may be important for the indicator of the proliferation status of LCLs, and the epigenetic viral gene regulation of EBNA2 gene by Wp should be further defined possibly with other biological processes

  5. Implementing the Synchronized Global Switch from Trivalent to Bivalent Oral Polio Vaccines-Lessons Learned From the Global Perspective.

    Science.gov (United States)

    Ramirez Gonzalez, Alejandro; Farrell, Margaret; Menning, Lisa; Garon, Julie; Everts, Hans; Hampton, Lee M; Dolan, Samantha B; Shendale, Stephanie; Wanyoike, Sarah; Veira, Chantal Laroche; Châtellier, Gaël Maufras du; Kurji, Feyrouz; Rubin, Jennifer; Boualam, Liliane; Chang Blanc, Diana; Patel, Manish

    2017-07-01

    In 2015, the Global Commission for the Certification of Polio Eradication certified the eradication of type 2 wild poliovirus, 1 of 3 wild poliovirus serotypes causing paralytic polio since the beginning of recorded history. This milestone was one of the key criteria prompting the Global Polio Eradication Initiative to begin withdrawal of oral polio vaccines (OPV), beginning with the type 2 component (OPV2), through a globally synchronized initiative in April and May 2016 that called for all OPV using countries and territories to simultaneously switch from use of trivalent OPV (tOPV; containing types 1, 2, and 3 poliovirus) to bivalent OPV (bOPV; containing types 1 and 3 poliovirus), thus withdrawing OPV2. Before the switch, immunization programs globally had been using approximately 2 billion tOPV doses per year to immunize hundreds of millions of children. Thus, the globally synchronized withdrawal of tOPV was an unprecedented achievement in immunization and was part of a crucial strategy for containment of polioviruses. Successful implementation of the switch called for intense global coordination during 2015-2016 on an unprecedented scale among global public health technical agencies and donors, vaccine manufacturers, regulatory agencies, World Health Organization (WHO) and United Nations Children's Fund (UNICEF) regional offices, and national governments. Priority activities included cessation of tOPV production and shipment, national inventories of tOPV, detailed forecasting of tOPV needs, bOPV licensing, scaling up of bOPV production and procurement, developing national operational switch plans, securing funding, establishing oversight and implementation committees and teams, training logisticians and health workers, fostering advocacy and communications, establishing monitoring and validation structures, and implementing waste management strategies. The WHO received confirmation that, by mid May 2016, all 155 countries and territories that had used OPV in

  6. Preparation of γ-immunoglobulins coupled with DTPA and their labelling with trivalent metal radionuclides for radiotherapy

    International Nuclear Information System (INIS)

    Rekova, M.; Miler, V.; Budsky, F.; Malek, Z.; Prokop, J.; Prazak, Z.

    2007-06-01

    The scope of the report is as follows: immunoglobulin coupling with cDTPAA and labelling of the conjugate with 90 Y; Acid-base and complexation equilibria in the coupled immunoglobulin solution; Theory of the complex equilibrium of yttrium between coupled immunoglobulin and EDTA; and Procedures and results of recent experiments. The following was achieved: (i) The dependence of the bovine immunoglobulin on the cDTPAA/IgG coupling ratio and immunoglobulin concentration was obtained; (ii) A procedure aimed to free phosphate buffer from ubiquitous trivalent cations was tested; (iii) The procedure of lyophilization of coupled bovine IgG-DTPA in a phosphate buffer at pH 7.34 and I = 0.16 mol.l -1 .was elaborated. (iv) A procedure for lyophilization of the coupled CD20 monoclonal antibody in the same phosphate buffer was elaborated. (v) Acid-base and complexation equilibria were calculated for citrate and phosphate buffer solutions in the presence of coupled immunoglobulin. ( vi) A theory of the complexation equilibrium of yttrium between coupled immunoglobulin and EDTA was developed. (vii) Experiments were performed leading to the determination of a so far unknown constant of complexity of yttrium to DTPA coupled to immunoglobulin; its 3rd and 4th dissociation constants. (viii) The method sub (vii) can be applied to the determination of the complexity constants of other radionuclides with DTPA coupled to immunoglobulin; the 3rd and 4th dissociation constants of IgG-DTPA will not have to be sought any more. (ix) Samples of lyophilizate of the Y-CD20-DTPA complex can be sent to the biochemical laboratory for immunoreactivity determination. (x) Lyophilizates from experiments (iv-vi) are stored in a refrigerator at 4 deg C to be used for labelling with 177 Lu. (xi) The results obtained can be used to plan an experiment with CD20 in which a specific radioactivity of 400 MBq 177 Lu per mg CD20 will be achieved. (P.A.)

  7. Structure, bioactivity, and synthesis of methylated flavonoids.

    Science.gov (United States)

    Wen, Lingrong; Jiang, Yueming; Yang, Jiali; Zhao, Yupeng; Tian, Miaomiao; Yang, Bao

    2017-06-01

    Methylated flavonoids are an important type of natural flavonoid derivative with potentially multiple health benefits; among other things, they have improved bioavailability compared with flavonoid precursors. Flavonoids have been documented to have broad bioactivities, such as anticancer, immunomodulation, and antioxidant activities, that can be elevated, to a certain extent, by methylation. Understanding the structure, bioactivity, and bioavailability of methylated flavonoids, therefore, is an interesting topic with broad potential applications. Though methylated flavonoids are widely present in plants, their levels are usually low. Because developing efficient techniques to produce these chemicals would likely be beneficial, we provide an overview of their chemical and biological synthesis. © 2017 New York Academy of Sciences.

  8. Colorectal Cancer "Methylator Phenotype": Fact or Artifact?

    Directory of Open Access Journals (Sweden)

    Charles Anacleto

    2005-04-01

    Full Text Available It has been proposed that human colorectal tumors can be classified into two groups: one in which methylation is rare, and another with methylation of several loci associated with a "CpG island methylated phenotype (CIMP," characterized by preferential proximal location in the colon, but otherwise poorly defined. There is considerable overlap between this putative methylator phenotype and the well-known mutator phenotype associated with microsatellite instability (MSI. We have examined hypermethylation of the promoter region of five genes (DAPK, MGMT, hMLH1, p16INK4a, and p14ARF in 106 primary colorectal cancers. A graph depicting the frequency of methylated loci in the series of tumors showed a continuous, monotonically decreasing distribution quite different from the previously claimed discontinuity. We observed a significant association between the presence of three or more methylated loci and the proximal location of the tumors. However, if we remove from analysis the tumors with hMLH1 methylation or those with MSI, the significance vanishes, suggesting that the association between multiple methylations and proximal location was indirect due to the correlation with MSI. Thus, our data do not support the independent existence of the so-called methylator phenotype and suggest that it rather may represent a statistical artifact caused by confounding of associations.

  9. Methylation diet and methyl group genetics in risk for adenomatous polyp occurrence

    Directory of Open Access Journals (Sweden)

    Mark Lucock

    2015-06-01

    Conclusion: A methylation diet influences methyl group synthesis in the regulation of blood homocysteine level, and is modulated by genetic interactions. Methylation-related nutrients also interact with key genes to modify risk of AP, a precursor of colorectal cancer. Independent of diet, two methylation-related genes (A2756G-MS and A66G-MSR were directly associated with AP occurrence.

  10. A genome-wide methylation study on obesity Differential variability and differential methylation

    NARCIS (Netherlands)

    Xu, Xiaojing; Su, Shaoyong; Barnes, Vernon A.; De Miguel, Carmen; Pollock, Jennifer; Ownby, Dennis; Shi, Huidong; Zhu, Haidong; Snieder, Harold; Wang, Xiaoling

    2013-01-01

    Besides differential methylation, DNA methylation variation has recently been proposed and demonstrated to be a potential contributing factor to cancer risk. Here we aim to examine whether differential variability in methylation is also an important feature of obesity, a typical non-malignant common

  11. 21 CFR 177.2000 - Vinylidene chloride/methyl acrylate/methyl methacrylate polymers.

    Science.gov (United States)

    2010-04-01

    ... methacrylate polymers. 177.2000 Section 177.2000 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF...: POLYMERS Substances for Use as Basic Components of Single and Repeated Use Food Contact Surfaces § 177.2000 Vinylidene chloride/methyl acrylate/methyl methacrylate polymers. The vinylidene chloride/methyl acrylate...

  12. Separation of trivalent actinides and lanthanides with some substituted oligopyridines and triazines in synergy with 2-bromodecanoic acid. (Presented at the International Solvent Extraction Conference, July 1999 in Barcelona)

    International Nuclear Information System (INIS)

    Enarsson, Aa.; Spjuth, L.; Liljenzin, J.O.; Kaellvenius, G.

    2000-01-01

    The separation of trivalent actinides and lanthanides with some substituted oligopyridines and triazines in synergy with 2-bromodecanoic acid was studied. All ligands, except the quinolinyl-derivatives, showed high metal extraction and good separation factors for trivalent actinides over lanthanides. The substituted di-pyridyltriazines and the quaterpyridine showed the highest distribution ratios and quater- and quinquepyridine the highest separation factors, at low nitric acid concentration. The basicity of the different ligands were determined by non-aqueous titration in acetonitrile media and was related to the metal extraction. The substituted di-pyridyltriazines, which showed the highest metal extraction also showed the lowest basicity

  13. Trivalent Human Papillomavirus (HPV) VLP vaccine covering HPV type 58 can elicit high level of humoral immunity but also induce immune interference among component types.

    Science.gov (United States)

    Zhang, Ting; Xu, Yufei; Qiao, Liang; Wang, Youchun; Wu, Xueling; Fan, Dongsheng; Peng, Qinglin; Xu, Xuemei

    2010-04-26

    Both Human Papillomavirus (HPV) type 16/18 bivalent vaccine and type 16/18/6/11 quadrivalent vaccine have been proved to be safe and effective, and licensed for public use. However, these two vaccines do not quite match the distribution of HPV types in China, Southeast Asia and Latin America, where HPV 58 is highly prevalent. Here we produced three types of virus-like particles (VLPs) in baculovirus expression system, formulated a trivalent vaccine containing HPV 16, 18, and 58 L1 VLPs and examined its in vitro neutralizing titers. This vaccine could induce high level and long-term humoral immunity against the component types. But immune interference was observed when comparing type specific neutralizing antibody levels induced by trivalent vaccine to those by corresponding monovalent vaccines. This kind of interference would become more obvious when formulating more types of VLPs into multivalent vaccines, but could be greatly overcome by decreasing the antigen dosage and adding a proper adjuvant. Copyright 2010 Elsevier Ltd. All rights reserved.

  14. Safety of a Trivalent Inactivated Influenza Vaccine in Health Care Workers in Kurdistan Province, Western Iran; A Longitudinal Follow-up Study.

    Science.gov (United States)

    Soltani, Jafar; Jamil Amjadi, Mohamad

    2014-03-01

    We studied the safety of a trivalent inactivated surface antigen (split virion, inactivated) influenza vaccine, Begrivac® (Novartis Company), widely used in health care workers in Kurdistan. A longitudinal follow-up study was performed in Sanandaj city, west of Iran, recruiting 936 people. A questionnaire was completed for each participant, and all symptoms or abnormal physical findings were recorded. In part 1 of the study, the post-vaccination complaints were headache (5.3%), fever (7.9%), weakness (9.6%), chills (10.1%), sweating (10.5%), arthralgia (20.2%), and malaise (21.5%). Swelling of the injection site was seen in 267 (30.3%) participants, and pruritus of the injection site was seen in 290 (32.9%) participants. Redness and induration were also reported in 42.5% of the participants. Local reactions were mainly mild and lasted for 1-2 days. No systemic reactions were reported in the second part of the study. None of the participants experienced any inconvenience. We concluded that local adverse reactions after the trivalent inactivated split influenza vaccine, Begrivac®, in health care workers were far more common than expected. Continuous surveillance is needed to assess the potential risks and benefits of newly produced influenza vaccines.

  15. Hybrid silica nanoparticles for sequestration and luminescence detection of trivalent rare-earth ions (Dy3+ and Nd3+) in solution

    Science.gov (United States)

    Topel, Seda Demirel; Legaria, Elizabeth Polido; Tiseanu, Carmen; Rocha, João; Nedelec, Jean-Marie; Kessler, Vadim G.; Seisenbaeva, Gulaim A.

    2014-12-01

    New hybrid material-based adsorbents acting also as luminescent probes upon uptake of trivalent rare-earth (RE) ions Nd3+ and Dy3+ have been developed. SiO2 NPs functionalized by three different organic ligands, N-aminopropylen-amido-iminodiacetic acid (L1), pyridine-α,β-dicarboxylic acid bis(propylenamide) (L2), and N-propylen-iminodiacetic acid (L3), have been produced and fully characterized by 13C, 1H, and 29Si solid-state NMR, FTIR, TGA, XRD, TEM, nitrogen gas adsorption, and also by NTA and DLS in solution. The synthesized hybrid materials are well dispersible and stable in aqueous solutions according to NTA and consist of spheres with diameters less than 100 nm. Their affinities to the lanthanide ions Dy3+ and Nd3+ have been investigated in aqueous solution and characterized by SEM-EDS and complexometric titration, demonstrating that they can be successfully used as adsorbents for sequestration of trivalent RE ions. The adsorbed RE ions can efficiently be desorbed from saturated nanoadsorbents by addition of hydrochloric acid. The produced nanomaterials may also be used as luminescent probes for Dy3+ and Nd3+ ions in solution.

  16. Simulant molecules with trivalent or pentavalent phosphorus atoms: bond dissociation energies and other thermodynamic and structural properties from quantum chemical models.

    Science.gov (United States)

    Hahn, David K; RaghuVeer, Krishans S; Ortiz, J V

    2011-08-04

    The CBS-QB3 and G4 thermochemical models have been used to generate energetic, structural, and spectroscopic data on a set of molecules with trivalent or pentavalent phosphorus atoms that can serve as simulants of chemical warfare agents. Based on structural data, the conformational stabilities of these molecules are explained in terms of the anomeric interaction within the OPOC and OPSC fragments. For those cases where experimental data are available, comparisons have been made between calculated and previously reported vibrational frequencies. All varieties of bond dissociation energies have been examined except those for C-H and P═O bonds. In trivalent phosphorus molecules, the O-C and S-C bonds have the lowest dissociation energies. In the pentavalent phosphorus set, the S-C bonds, followed by P-S bonds, have the lowest dissociation energies. In the fluorinated simulant molecules, the P-F bond is strongest, and the P-C or O-C bonds are weakest. © 2011 American Chemical Society

  17. Bioreduction of trivalent aurum to nano-crystalline gold particles by active and inactive cells and cell-free extract of Aspergillus oryzae var. viridis

    International Nuclear Information System (INIS)

    Binupriya, A.R.; Sathishkumar, M.; Vijayaraghavan, K.; Yun, S.-I.

    2010-01-01

    Bioreduction efficacy of both active (AB) and inactive (IB) cells/biomass of Aspergillus oryzae var. viridis and their respective cell-free extracts (ACE and ICE) to convert trivalent aurum to gold nanoparticles were tested in the present study. Strong plasmon resonance of gold nanoparticles was observed between 540 and 560 nm in the samples obtained from AB, IB, ACE and ICE. Transmission electron microscopy (TEM), field emission scanning electron microscopy (FE-SEM), energy dispersive X-ray (EDX) and X-ray diffraction (XRD) were performed to examine the formation of gold nanoparticles. Comparing all four forms of A. oryzae var. viridis, ICE showed high gold nanoparticle productivity. The nanoparticles formed were quite uniform in shape and ranged in size from 10 to 60 nm. In addition some triangle, pentagon and hexagon-shaped nanoplates with size range of 30-400 nm were also synthesized especially at lower pH. Organics from the inactive cells are believed to be responsible for reduction of trivalent aurum to nano-sized gold particles. Organic content of the ICE was found to be double the amount of ACE. High productivity of gold nanoparticles by metabolic-independent process opens up an interesting area of nanoparticle synthesis using waste fungal biomass from industries.

  18. Bioreduction of trivalent aurum to nano-crystalline gold particles by active and inactive cells and cell-free extract of Aspergillus oryzae var. viridis

    Energy Technology Data Exchange (ETDEWEB)

    Binupriya, A.R. [Department of Food Science and Technology, College of Agriculture and Life Science, Chonbuk National University, Jeonju 561-756 (Korea, Republic of); Sathishkumar, M., E-mail: cvemuthu@nus.edu.sg [Singapore-Delft Water Alliance, National University of Singapore, 2 Engineering Drive 2, Singapore 117577 (Singapore); Vijayaraghavan, K. [Singapore-Delft Water Alliance, National University of Singapore, 2 Engineering Drive 2, Singapore 117577 (Singapore); Yun, S.-I., E-mail: siyun@chonbuk.ac.kr [Department of Food Science and Technology, College of Agriculture and Life Science, Chonbuk National University, Jeonju 561-756 (Korea, Republic of)

    2010-05-15

    Bioreduction efficacy of both active (AB) and inactive (IB) cells/biomass of Aspergillus oryzae var. viridis and their respective cell-free extracts (ACE and ICE) to convert trivalent aurum to gold nanoparticles were tested in the present study. Strong plasmon resonance of gold nanoparticles was observed between 540 and 560 nm in the samples obtained from AB, IB, ACE and ICE. Transmission electron microscopy (TEM), field emission scanning electron microscopy (FE-SEM), energy dispersive X-ray (EDX) and X-ray diffraction (XRD) were performed to examine the formation of gold nanoparticles. Comparing all four forms of A. oryzae var. viridis, ICE showed high gold nanoparticle productivity. The nanoparticles formed were quite uniform in shape and ranged in size from 10 to 60 nm. In addition some triangle, pentagon and hexagon-shaped nanoplates with size range of 30-400 nm were also synthesized especially at lower pH. Organics from the inactive cells are believed to be responsible for reduction of trivalent aurum to nano-sized gold particles. Organic content of the ICE was found to be double the amount of ACE. High productivity of gold nanoparticles by metabolic-independent process opens up an interesting area of nanoparticle synthesis using waste fungal biomass from industries.

  19. Blocking herpes simplex virus 2 glycoprotein E immune evasion as an approach to enhance efficacy of a trivalent subunit antigen vaccine for genital herpes.

    Science.gov (United States)

    Awasthi, Sita; Huang, Jialing; Shaw, Carolyn; Friedman, Harvey M

    2014-08-01

    Herpes simplex virus 2 (HSV-2) subunit antigen vaccines targeting virus entry molecules have failed to prevent genital herpes in human trials. Our approach is to include a virus entry molecule and add antigens that block HSV-2 immune evasion. HSV-2 glycoprotein C (gC2) is an immune evasion molecule that inhibits complement. We previously reported that adding gC2 to gD2 improved vaccine efficacy compared to the efficacy of either antigen alone in mice and guinea pigs. Here we demonstrate that HSV-2 glycoprotein E (gE2) functions as an immune evasion molecule by binding the IgG Fc domain. HSV-2 gE2 is synergistic with gC2 in protecting the virus from antibody and complement neutralization. Antibodies produced by immunization with gE2 blocked gE2-mediated IgG Fc binding and cell-to-cell spread. Mice immunized with gE2 were only partially protected against HSV-2 vaginal challenge in mice; however, when gE2 was added to gC2/gD2 to form a trivalent vaccine, neutralizing antibody titers with and without complement were significantly higher than those produced by gD2 alone. Importantly, the trivalent vaccine protected the dorsal root ganglia (DRG) of 32/33 (97%) mice between days 2 and 7 postchallenge, compared with 27/33 (82%) in the gD2 group. The HSV-2 DNA copy number was significantly lower in mice immunized with the trivalent vaccine than in those immunized with gD2 alone. The extent of DRG protection using the trivalent vaccine was better than what we previously reported for gC2/gD2 immunization. Therefore, gE2 is a candidate antigen for inclusion in a multivalent subunit vaccine that attempts to block HSV-2 immune evasion. Herpes simplex virus is the most common cause of genital ulcer disease worldwide. Infection results in emotional distress for infected individuals and their partners, is life threatening for infants exposed to herpes during childbirth, and greatly increases the risk of individuals acquiring and transmitting HIV infection. A vaccine that prevents

  20. Aberrant TET1 Methylation Closely Associated with CpG Island Methylator Phenotype in Colorectal Cancer.

    Science.gov (United States)

    Ichimura, Norihisa; Shinjo, Keiko; An, Byonggu; Shimizu, Yasuhiro; Yamao, Kenji; Ohka, Fumiharu; Katsushima, Keisuke; Hatanaka, Akira; Tojo, Masayuki; Yamamoto, Eiichiro; Suzuki, Hiromu; Ueda, Minoru; Kondo, Yutaka

    2015-08-01

    Inactivation of methylcytosine dioxygenase, ten-eleven translocation (TET) is known to be associated with aberrant DNA methylation in cancers. Tumors with a CpG island methylator phenotype (CIMP), a distinct subgroup with extensive DNA methylation, show characteristic features in the case of colorectal cancer. The relationship between TET inactivation and CIMP in colorectal cancers is not well understood. The expression level of TET family genes was compared between CIMP-positive (CIMP-P) and CIMP-negative (CIMP-N) colorectal cancers. Furthermore, DNA methylation profiling, including assessment of the TET1 gene, was assessed in colorectal cancers, as well as colon polyps. The TET1 was silenced by DNA methylation in a subset of colorectal cancers as well as cell lines, expression of which was reactivated by demethylating agent. TET1 methylation was more frequent in CIMP-P (23/55, 42%) than CIMP-N (2/113, 2%, P CIMP-P, 16/40, 40%; CIMP-N, 2/24, 8%; P = 0.002), suggesting that TET1 methylation is an early event in CIMP tumorigenesis. TET1 methylation was significantly associated with BRAF mutation but not with hMLH1 methylation in the CIMP-P colorectal cancers. Colorectal cancers with TET1 methylation have a significantly greater number of DNA methylated genes and less pathological metastasis compared to those without TET1 methylation (P = 0.007 and 0.045, respectively). Our data suggest that TET1 methylation may contribute to the establishment of a unique pathway in respect to CIMP-mediated tumorigenesis, which may be incidental to hMLH1 methylation. In addition, our findings provide evidence that TET1 methylation may be a good biomarker for the prediction of metastasis in colorectal cancer. ©2015 American Association for Cancer Research.

  1. The Synthesis of Methyl Salicylate: Amine Diazotization.

    Science.gov (United States)

    Zanger, Murray; McKee, James R.

    1988-01-01

    Notes that this experiment takes safety and noncarcinogenic reactants into account. Demonstrates the use of diazonium salts for the replacement of an aromatic amine group by a phenolic hydroxyl. Involves two pleasant-smelling organic compounds, methyl anthranilate (grape) and methyl salicylate (oil of wintergreen). (MVL)

  2. Evidence Suggesting Absence of Mitochondrial DNA Methylation

    DEFF Research Database (Denmark)

    Mechta, Mie; Ingerslev, Lars R; Fabre, Odile

    2017-01-01

    , 16S, ND5 and CYTB, suggesting that mtDNA supercoiled structure blocks the access to bisulfite conversion. Here, we identified an artifact of mtDNA bisulfite sequencing that can lead to an overestimation of mtDNA methylation levels. Our study supports that cytosine methylation is virtually absent...

  3. DNA Methylation Modulates Nociceptive Sensitization after Incision.

    Directory of Open Access Journals (Sweden)

    Yuan Sun

    Full Text Available DNA methylation is a key epigenetic mechanism controlling DNA accessibility and gene expression. Blockade of DNA methylation can significantly affect pain behaviors implicated in neuropathic and inflammatory pain. However, the role of DNA methylation with regard to postoperative pain has not yet been explored. In this study we sought to investigate the role of DNA methylation in modulating incisional pain and identify possible targets under DNA methylation and contributing to incisional pain. DNA methyltranferase (DNMT inhibitor 5-Aza-2'-deoxycytidine significantly reduced incision-induced mechanical allodynia and thermal sensitivity. Aza-2'-deoxycytidine also reduced hindpaw swelling after incision, suggesting an anti-inflammatory effect. Global DNA methylation and DNMT3b expression were increased in skin after incision, but none of DNMT1, DNMT3a or DNMT3b was altered in spinal cord or DRG. The expression of proopiomelanocortin Pomc encoding β-endorphin and Oprm1 encoding the mu-opioid receptor were upregulated peripherally after incision; moreover, Oprm1 expression was further increased under DNMT inhibitor treatment. Finally, local peripheral injection of the opioid receptor antagonist naloxone significantly exacerbated incision-induced mechanical hypersensitivity. These results suggest that DNA methylation is functionally relevant to incisional nociceptive sensitization, and that mu-opioid receptor signaling might be one methylation regulated pathway controlling sensitization after incision.

  4. Methyl 3-(Quinolin-2-ylindolizine-1-carboxylate

    Directory of Open Access Journals (Sweden)

    Roumaissa Belguedj

    2015-12-01

    Full Text Available A novel compound, methyl 3-(quinolin-2-ylindolizine-1-carboxylate (2 has been synthesized by cycloaddition reaction of 1-(quinolin-2-ylmethylpyridinium ylide (1 with methyl propiolate in presence of sodium hydride in THF. The structure of this compound was established by IR, 1H-NMR, 13C-NMR and MS data

  5. Adenine N6-methylation in diverse fungi

    NARCIS (Netherlands)

    Seidl, Michael F.

    2017-01-01

    A DNA modification - methylation of cytosines and adenines - has important roles in diverse processes such as regulation of gene expression and genome stability, yet until recently adenine methylation had been considered to be only a hallmark of prokaryotes. A new study identifies abundant

  6. Effects of cytosine methylation on transcription factor binding sites

    KAUST Repository

    Medvedeva, Yulia A; Khamis, Abdullah M.; Kulakovskiy, Ivan V; Ba Alawi, Wail; Bhuyan, Md Shariful I; Kawaji, Hideya; Lassmann, Timo; Harbers, Matthias; Forrest, Alistair RR; Bajic, Vladimir B.

    2014-01-01

    Background: DNA methylation in promoters is closely linked to downstream gene repression. However, whether DNA methylation is a cause or a consequence of gene repression remains an open question. If it is a cause, then DNA methylation may affect

  7. DMPD: TLR ignores methylated RNA? [Dynamic Macrophage Pathway CSML Database

    Lifescience Database Archive (English)

    Full Text Available 16111629 TLR ignores methylated RNA? Ishii KJ, Akira S. Immunity. 2005 Aug;23(2):11...1-3. (.png) (.svg) (.html) (.csml) Show TLR ignores methylated RNA? PubmedID 16111629 Title TLR ignores methylated

  8. Modeling spatiotemporal dynamics of DNA methylation

    DEFF Research Database (Denmark)

    Lövkvist, Cecilia Elisabet

    into how epigenetic marks are distributed in the human genome. In the first part of the thesis, we investigate DNA methylation and maintenance of methylation patterns throughout cell division. We argue that collaborative models, those where the methylation of CpG sites depends on the methylation status...... into the game more explicitly in another type of model that speaks out the duality of the two aspects. Using statistical analysis of experimental data, this thesis further explores a link between DNA methylation and nucleosome occupancy. By comparing the patterns on promoters to regions with similar Cp...... division. The patterns of epigentic marks depend on enzymes that ensure their maintenance and introduction. Using theoretical models, this thesis proposes new mechanisms for how enzymes operate to maintain patterns of epigenetic marks. Through analysis of experimental data this work gives new insight...

  9. Protein methylation reactions in intact pea chloroplasts

    International Nuclear Information System (INIS)

    Niemi, K.J.

    1989-01-01

    Post-translational protein methylation was investigated in Pisum sativum chloroplasts. Intact pea chloroplasts were incubated with ( 3 H-methyl)-S-adenosylmethionine under various conditions. The chloroplasts were then separated into stromal and thylakoid fractions and analyzed for radioactivity transferred to protein. Light enhanced the magnitude of labeling in both fractions. One thylakoid polypeptide with an apparent molecular mass of 43 kDa was labeled only in the light. Several other thylakoid and stromal proteins were labeled in both light and dark-labeling conditions. Both base-labile methylation, carboxy-methylesters and base-stable groups, N-methylations were found. Further characterization of the methyl-transfer reactions will be presented

  10. Radiation effects on DNA methylation in mice

    International Nuclear Information System (INIS)

    Komura, J.; Kurishita, A.; Miyamura, Y.; Ono, T.; Tawa, R.; Sakurai, H.

    1992-01-01

    Effects of ionizing radiation on DNA methylation in liver, brain and spleen were examined by high performance liquid chromatography (HPLC). The total methylated cytosine level in the genome was reduced within 8 hours after 3.8 Gy of irradiation in liver of adult mice. But no appreciable effect was observed in brain and spleen. When mice were irradiated at newborn, liver DNA revealed no change in methylated cytosine level. Even though slight effects of radiation were detected in he methylation of the c-myc and c-fos genes, they were only temporary and no long-term effects were observed. These data suggest that the effect of radiation on DNA methylation in vivo is not prevailing a DNA damage, but rather influenced much through biological parameters. (author)

  11. Methylation analysis of polysaccharides: Technical advice.

    Science.gov (United States)

    Sims, Ian M; Carnachan, Susan M; Bell, Tracey J; Hinkley, Simon F R

    2018-05-15

    Glycosyl linkage (methylation) analysis is used widely for the structural determination of oligo- and poly-saccharides. The procedure involves derivatisation of the individual component sugars of a polysaccharide to partially methylated alditol acetates which are analysed and quantified by gas chromatography-mass spectrometry. The linkage positions for each component sugar can be determined by correctly identifying the partially methylated alditol acetates. Although the methods are well established, there are many technical aspects to this procedure and both careful attention to detail and considerable experience are required to achieve a successful methylation analysis and to correctly interpret the data generated. The aim of this article is to provide the technical details and critical procedural steps necessary for a successful methylation analysis and to assist researchers (a) with interpreting data correctly and (b) in providing the comprehensive data required for reviewers to fully assess the work. Copyright © 2018 Elsevier Ltd. All rights reserved.

  12. DNA sequence explains seemingly disordered methylation levels in partially methylated domains of Mammalian genomes.

    Directory of Open Access Journals (Sweden)

    Dimos Gaidatzis

    2014-02-01

    Full Text Available For the most part metazoan genomes are highly methylated and harbor only small regions with low or absent methylation. In contrast, partially methylated domains (PMDs, recently discovered in a variety of cell lines and tissues, do not fit this paradigm as they show partial methylation for large portions (20%-40% of the genome. While in PMDs methylation levels are reduced on average, we found that at single CpG resolution, they show extensive variability along the genome outside of CpG islands and DNase I hypersensitive sites (DHS. Methylation levels range from 0% to 100% in a roughly uniform fashion with only little similarity between neighboring CpGs. A comparison of various PMD-containing methylomes showed that these seemingly disordered states of methylation are strongly conserved across cell types for virtually every PMD. Comparative sequence analysis suggests that DNA sequence is a major determinant of these methylation states. This is further substantiated by a purely sequence based model which can predict 31% (R(2 of the variation in methylation. The model revealed CpG density as the main driving feature promoting methylation, opposite to what has been shown for CpG islands, followed by various dinucleotides immediately flanking the CpG and a minor contribution from sequence preferences reflecting nucleosome positioning. Taken together we provide a reinterpretation for the nucleotide-specific methylation levels observed in PMDs, demonstrate their conservation across tissues and suggest that they are mainly determined by specific DNA sequence features.

  13. Detection of DNA methylation changes in micropropagated banana plants using methylation-sensitive amplification polymorphism (MSAP).

    Science.gov (United States)

    Peraza-Echeverria, S; Herrera-Valencia, V A.; Kay, A -J.

    2001-07-01

    The extent of DNA methylation polymorphisms was evaluated in micropropagated banana (Musa AAA cv. 'Grand Naine') derived from either the vegetative apex of the sucker or the floral apex of the male inflorescence using the methylation-sensitive amplification polymorphism (MSAP) technique. In all, 465 fragments, each representing a recognition site cleaved by either or both of the isoschizomers were amplified using eight combinations of primers. A total of 107 sites (23%) were found to be methylated at cytosine in the genome of micropropagated banana plants. In plants micropropagated from the male inflorescence explant 14 (3%) DNA methylation events were polymorphic, while plants micropropagated from the sucker explant produced 8 (1.7%) polymorphisms. No DNA methylation polymorphisms were detected in conventionally propagated banana plants. These results demonstrated the usefulness of MSAP to detect DNA methylation events in micropropagated banana plants and indicate that DNA methylation polymorphisms are associated with micropropagation.

  14. The origin and fate of 4-methyl steroid hydrocarbons. I. Diagenesis of 4-methyl sterenes

    Science.gov (United States)

    Wolff, George A.; Lamb, Neil A.; Maxwell, James R.

    1986-03-01

    Treatment of 4-methylcholest-4-ene under mild acid conditions at low temperatures gives chemical evidence for certain features seen in the distributions of sedimentary 4-methyl steroid hydrocarbons, and further indicates that many low temperature diagenetic reactions of steroids are explicable in terms of acid catalysed rearrangements. Specifically, the results provide: (i) Indirect evidence that the 4-ene skeleton is a key intermediate in the dehydration of 4-methyl stanols in sediments. (ii) An explanation for the distribution of 4-methyl sterenes and A-nor sterenes in the lacustrine Messel shale (Eocene). (iii) An explanation for the presence of 4β-methyl steranes in relatively immature sedimentary rocks, despite the precursor stanols having the 4α-methyl configuration. With increasing maturity in the Paris Basin shales (Lower Toarcian), the less stable 4β-methyl steranes decrease gradually in abundance relative to their 4α-methyl counterparts, at a rate fairly similar to the change in pristane stereochemistry.

  15. Implementation of coordinated global serotype 2 oral poliovirus vaccine cessation: risks of inadvertent trivalent oral poliovirus vaccine use.

    Science.gov (United States)

    Duintjer Tebbens, Radboud J; Hampton, Lee M; Thompson, Kimberly M

    2016-06-01

    The endgame for polio eradication includes coordinated global cessation of oral poliovirus vaccine (OPV), starting with the cessation of vaccine containing OPV serotype 2 (OPV2) by switching all trivalent OPV (tOPV) to bivalent OPV (bOPV). The logistics associated with this global switch represent a significant undertaking, with some possibility of inadvertent tOPV use after the switch. We used a previously developed poliovirus transmission and OPV evolution model to explore the relationships between the extent of inadvertent tOPV use, the time after the switch of the inadvertent tOPV use and corresponding population immunity to serotype 2 poliovirus transmission, and the ability of the inadvertently introduced viruses to cause a serotype 2 circulating vaccine-derived poliovirus (cVDPV2) outbreak in a hypothetical population. We then estimated the minimum time until inadvertent tOPV use in a supplemental immunization activity (SIA) or in routine immunization (RI) can lead to a cVDPV2 outbreak in realistic populations with properties like those of northern India, northern Pakistan and Afghanistan, northern Nigeria, and Ukraine. At low levels of inadvertent tOPV use, the minimum time after the switch for the inadvertent use to cause a cVDPV2 outbreak decreases sharply with increasing proportions of children inadvertently receiving tOPV. The minimum times until inadvertent tOPV use in an SIA or in RI can lead to a cVDPV2 outbreak varies widely among populations, with higher basic reproduction numbers, lower tOPV-induced population immunity to serotype 2 poliovirus transmission prior to the switch, and a lower proportion of transmission occurring via the oropharyngeal route all resulting in shorter times. In populations with the lowest expected immunity to serotype 2 poliovirus transmission after the switch, inadvertent tOPV use in an SIA leads to a cVDPV2 outbreak if it occurs as soon as 9 months after the switch with 0.5 % of children aged 0-4 years inadvertently

  16. Global DNA methylation analysis using methyl-sensitive amplification polymorphism (MSAP).

    Science.gov (United States)

    Yaish, Mahmoud W; Peng, Mingsheng; Rothstein, Steven J

    2014-01-01

    DNA methylation is a crucial epigenetic process which helps control gene transcription activity in eukaryotes. Information regarding the methylation status of a regulatory sequence of a particular gene provides important knowledge of this transcriptional control. DNA methylation can be detected using several methods, including sodium bisulfite sequencing and restriction digestion using methylation-sensitive endonucleases. Methyl-Sensitive Amplification Polymorphism (MSAP) is a technique used to study the global DNA methylation status of an organism and hence to distinguish between two individuals based on the DNA methylation status determined by the differential digestion pattern. Therefore, this technique is a useful method for DNA methylation mapping and positional cloning of differentially methylated genes. In this technique, genomic DNA is first digested with a methylation-sensitive restriction enzyme such as HpaII, and then the DNA fragments are ligated to adaptors in order to facilitate their amplification. Digestion using a methylation-insensitive isoschizomer of HpaII, MspI is used in a parallel digestion reaction as a loading control in the experiment. Subsequently, these fragments are selectively amplified by fluorescently labeled primers. PCR products from different individuals are compared, and once an interesting polymorphic locus is recognized, the desired DNA fragment can be isolated from a denaturing polyacrylamide gel, sequenced and identified based on DNA sequence similarity to other sequences available in the database. We will use analysis of met1, ddm1, and atmbd9 mutants and wild-type plants treated with a cytidine analogue, 5-azaC, or zebularine to demonstrate how to assess the genetic modulation of DNA methylation in Arabidopsis. It should be noted that despite the fact that MSAP is a reliable technique used to fish for polymorphic methylated loci, its power is limited to the restriction recognition sites of the enzymes used in the genomic

  17. DNA methylation analysis reveals distinct methylation signatures in pediatric germ cell tumors

    International Nuclear Information System (INIS)

    Amatruda, James F; Frazier, A Lindsay; Poynter, Jenny N; Ross, Julie A; Christensen, Brock; Fustino, Nicholas J; Chen, Kenneth S; Hooten, Anthony J; Nelson, Heather; Kuriger, Jacquelyn K; Rakheja, Dinesh

    2013-01-01

    Aberrant DNA methylation is a prominent feature of many cancers, and may be especially relevant in germ cell tumors (GCTs) due to the extensive epigenetic reprogramming that occurs in the germ line during normal development. We used the Illumina GoldenGate Cancer Methylation Panel to compare DNA methylation in the three main histologic subtypes of pediatric GCTs (germinoma, teratoma and yolk sac tumor (YST); N = 51) and used recursively partitioned mixture models (RPMM) to test associations between methylation pattern and tumor and demographic characteristics. We identified genes and pathways that were differentially methylated using generalized linear models and Ingenuity Pathway Analysis. We also measured global DNA methylation at LINE1 elements and evaluated methylation at selected imprinted loci using pyrosequencing. Methylation patterns differed by tumor histology, with 18/19 YSTs forming a distinct methylation class. Four pathways showed significant enrichment for YSTs, including a human embryonic stem cell pluripotency pathway. We identified 190 CpG loci with significant methylation differences in mature and immature teratomas (q < 0.05), including a number of CpGs in stem cell and pluripotency-related pathways. Both YST and germinoma showed significantly lower methylation at LINE1 elements compared with normal adjacent tissue while there was no difference between teratoma (mature and immature) and normal tissue. DNA methylation at imprinted loci differed significantly by tumor histology and location. Understanding methylation patterns may identify the developmental stage at which the GCT arose and the at-risk period when environmental exposures could be most harmful. Further, identification of relevant genetic pathways could lead to the development of new targets for therapy

  18. Theoretical investigations of the optical and EPR spectra for trivalent cerium and ytterbium ions in orthorhombic YF{sub 3} crystal

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Hong-Gang, E-mail: kezhouliu@163.com; Zheng, Wen-Chen

    2016-09-01

    The optical spectra and electron paramagnetic resonance (EPR) parameters (g factors and hyperfine structure constants A) for trivalent cerium and ytterbium ions in YF{sub 3} crystal with orthorhombic structure are investigated together by the complete diagonalization (of energy matrix) method (CDM). The obtained results are in reasonable agreement with the experimental ones. More importantly, two magnetically nonequivalent centers in YF{sub 3} crystal observed in EPR experiments are confirmed and ascribed to their specific positions in a unit cell by our calculations based on superposition model (SPM) analysis. Such identification of local sites with different magnetic properties would help us to understand not only the EPR spectra and magnetic susceptibility of other lanthanide ions doped in crystals with the same structure as YF{sub 3} but also the energy transfer scheme between two lanthanide ions occupying such two sites. All results are discussed carefully.

  19. A recombinant pseudorabies virus co-expressing capsid proteins precursor P1-2A of FMDV and VP2 protein of porcine parvovirus: a trivalent vaccine candidate.

    Science.gov (United States)

    Hong, Qi; Qian, Ping; Li, Xiang-Min; Yu, Xiao-Lan; Chen, Huan-Chun

    2007-11-01

    Pseudorabies (PR), foot-and-mouth disease (FMD), and porcine parvovirus disease are three important infectious diseases in swine worldwide. The gene-deleted pseudorabies virus (PRV) has been used as a live-viral vector to develop multivalent genetic engineering vaccine. In this study, a recombinant PRV, which could co-express protein precursor P1-2A of FMDV and VP2 protein of PPV, was constructed using PRV TK(-)/gE(-)/LacZ(+) mutant as the vector. After homologous recombination and plaque purification, recombinant virus PRV TK(-)/gE(-)/P1-2A-VP2 was acquired and identified. Immunogenicity, safety of the recombinant PRV and its protection against PRV were confirmed in a mouse model by indirect ELISA and serum neutralization test. The results show that the recombinant PRV is a candidate vaccine strain to develop a novel trivalent vaccine against PRV, FMDV and PPV in swine.

  20. Immunogenicity and safety assessment of a trivalent, inactivated split influenza vaccine in Korean children: Double-blind, randomized, active-controlled multicenter phase III clinical trial.

    Science.gov (United States)

    Han, Seung Beom; Rhim, Jung-Woo; Shin, Hye Jo; Lee, Soo Young; Kim, Hyun-Hee; Kim, Jong-Hyun; Lee, Kyung-Yil; Ma, Sang Hyuk; Park, Joon Soo; Kim, Hwang Min; Kim, Chun Soo; Kim, Dong Ho; Choi, Young Youn; Cha, Sung-Ho; Hong, Young Jin; Kang, Jin Han

    2015-01-01

    A multicenter, double-blind, randomized, active-control phase III clinical trial was performed to assess the immunogenicity and safety of a trivalent, inactivated split influenza vaccine. Korean children between the ages of 6 months and 18 y were enrolled and randomized into a study (study vaccine) or a control vaccine group (commercially available trivalent, inactivated split influenza vaccine) in a 5:1 ratio. Antibody responses were determined using hemagglutination inhibition assay, and post-vaccination immunogenicity was assessed based on seroconversion and seroprotection rates. For safety assessment, solicited local and systemic adverse events up to 28 d after vaccination and unsolicited adverse events up to 6 months after vaccination were evaluated. Immunogenicity was assessed in 337 and 68 children of the study and control groups. In the study vaccine group, seroconversion rates against influenza A/H1N1, A/H3N2, and B strains were 62.0% (95% CI: 56.8-67.2), 53.4% (95% CI: 48.1-58.7), and 54.9% (95% CI: 48.1-60.2), respectively. The corresponding seroprotection rates were 95.0% (95% CI: 92.6-97.3), 93.8% (95% CI: 91.2-96.4), and 95.3% (95% CI: 93.0-97.5). The lower 95% CI limits of the seroconversion and seroprotection rates were over 40% and 70%, respectively, against all strains. Seroconversion and seroprotection rates were not significantly different between the study and control vaccine groups. Furthermore, the frequencies of adverse events were not significantly different between the 2 vaccine groups, and no serious vaccination-related adverse events were noted. In conclusion, the study vaccine exhibited substantial immunogenicity and safety in Korean children and is expected to be clinically effective.

  1. Efficacy of a potential trivalent vaccine based on Hc fragments of botulinum toxins A, B, and E produced in a cell-free expression system.

    Science.gov (United States)

    Zichel, R; Mimran, A; Keren, A; Barnea, A; Steinberger-Levy, I; Marcus, D; Turgeman, A; Reuveny, S

    2010-05-01

    Botulinum toxins produced by the anaerobic bacterium Clostridium botulinum are the most potent biological toxins in nature. Traditionally, people at risk are immunized with a formaldehyde-inactivated toxin complex. Second generation vaccines are based on the recombinant carboxy-terminal heavy-chain (Hc) fragment of the neurotoxin. However, the materialization of this approach is challenging, mainly due to the high AT content of clostridial genes. Herein, we present an alternative strategy in which the native genes encoding Hc proteins of botulinum toxins A, B, and E were used to express the recombinant Hc fragments in a cell-free expression system. We used the unique property of this open system to introduce different combinations of chaperone systems, protein disulfide isomerase (PDI), and reducing/oxidizing environments directly to the expression reaction. Optimized expression conditions led to increased production of soluble Hc protein, which was successfully scaled up using a continuous exchange (CE) cell-free system. Hc proteins were produced at a concentration of more than 1 mg/ml and purified by one-step Ni(+) affinity chromatography. Mice immunized with three injections containing 5 microg of any of the in vitro-expressed, alum-absorbed, Hc vaccines generated a serum enzyme-linked immunosorbent assay (ELISA) titer of 10(5) against the native toxin complex, which enabled protection against a high-dose toxin challenge (10(3) to 10(6) mouse 50% lethal dose [MsLD(50)]). Finally, immunization with a trivalent HcA, HcB, and HcE vaccine protected mice against the corresponding trivalent 10(5) MsLD(50) toxin challenge. Our results together with the latest developments in scalability of the in vitro protein expression systems offer alternative routes for the preparation of botulinum vaccine.

  2. Evaluating genome-wide DNA methylation changes in mice by Methylation Specific Digital Karyotyping

    Directory of Open Access Journals (Sweden)

    Maruoka Shuichiro

    2008-12-01

    Full Text Available Abstract Background The study of genome-wide DNA methylation changes has become more accessible with the development of various array-based technologies though when studying species other than human the choice of applications are limited and not always within reach. In this study, we adapted and tested the applicability of Methylation Specific Digital Karyotyping (MSDK, a non-array based method, for the prospective analysis of epigenetic changes after perinatal nutritional modifications in a mouse model of allergic airway disease. MSDK is a sequenced based method that allows a comprehensive and unbiased methylation profiling. The method generates 21 base pairs long sequence tags derived from specific locations in the genome. The resulting tag frequencies determine in a quantitative manner the methylation level of the corresponding loci. Results Genomic DNA from whole lung was isolated and subjected to MSDK analysis using the methylation-sensitive enzyme Not I as the mapping enzyme and Nla III as the fragmenting enzyme. In a pair wise comparison of the generated mouse MSDK libraries we identified 158 loci that are significantly differentially methylated (P-value = 0.05 after perinatal dietary changes in our mouse model. Quantitative methylation specific PCR and sequence analysis of bisulfate modified genomic DNA confirmed changes in methylation at specific loci. Differences in genomic MSDK tag counts for a selected set of genes, correlated well with changes in transcription levels as measured by real-time PCR. Furthermore serial analysis of gene expression profiling demonstrated a dramatic difference in expressed transcripts in mice exposed to perinatal nutritional changes. Conclusion The genome-wide methylation survey applied in this study allowed for an unbiased methylation profiling revealing subtle changes in DNA methylation in mice maternally exposed to dietary changes in methyl-donor content. The MSDK method is applicable for mouse models

  3. Homogalacturonan methyl-esterification and plant development.

    Science.gov (United States)

    Wolf, Sebastian; Mouille, Grégory; Pelloux, Jérome

    2009-09-01

    The ability of a plant cell to expand is largely defined by the physical constraints imposed by its cell wall. Accordingly, cell wall properties have to be regulated during development. The pectic polysaccharide homogalacturonan is a major component of the plant primary walls. Biosynthesis and in muro modification of homogalacturonan have recently emerged as key determinants of plant development, controlling cell adhesion, organ development, and phyllotactic patterning. This review will focus on recent findings regarding impact of homogalacturonan content and methyl-esterification status of this polymer on plant life. De-methyl-esterification of homogalacturonan occurs through the action of the ubiquitous enzyme 'pectin methyl-esterase'. We here describe various strategies developed by the plant to finely tune the methyl-esterification status of homogalacturonan along key events of the plant lifecycle.

  4. Annotating the genome by DNA methylation.

    Science.gov (United States)

    Cedar, Howard; Razin, Aharon

    2017-01-01

    DNA methylation plays a prominent role in setting up and stabilizing the molecular design of gene regulation and by understanding this process one gains profound insight into the underlying biology of mammals. In this article, we trace the discoveries that provided the foundations of this field, starting with the mapping of methyl groups in the genome and the experiments that helped clarify how methylation patterns are maintained through cell division. We then address the basic relationship between methyl groups and gene repression, as well as the molecular rules involved in controlling this process during development in vivo. Finally, we describe ongoing work aimed at defining the role of this modification in disease and deciphering how it may serve as a mechanism for sensing the environment.

  5. Methylation of hemoglobin to enhance flocculant performance

    Science.gov (United States)

    An inexpensive bioflocculant, bovine hemoglobin (Hb), has been covalently modified through methylation of the side chain carboxyl groups of aspartic and glutamic acid residues to improve its flocculation activity. Potentiometric titration of the recovered products showed approximately 28% degree of ...

  6. Analysis of DNA methylation in Arabidopsis thaliana based on methylation-sensitive AFLP markers.

    Science.gov (United States)

    Cervera, M T; Ruiz-García, L; Martínez-Zapater, J M

    2002-12-01

    AFLP analysis using restriction enzyme isoschizomers that differ in their sensitivity to methylation of their recognition sites has been used to analyse the methylation state of anonymous CCGG sequences in Arabidopsis thaliana. The technique was modified to improve the quality of fingerprints and to visualise larger numbers of scorable fragments. Sequencing of amplified fragments indicated that detection was generally associated with non-methylation of the cytosine to which the isoschizomer is sensitive. Comparison of EcoRI/ HpaII and EcoRI/ MspI patterns in different ecotypes revealed that 35-43% of CCGG sites were differentially digested by the isoschizomers. Interestingly, the pattern of digestion among different plants belonging to the same ecotype is highly conserved, with the rate of intra-ecotype methylation-sensitive polymorphisms being less than 1%. However, pairwise comparisons of methylation patterns between samples belonging to different ecotypes revealed differences in up to 34% of the methylation-sensitive polymorphisms. The lack of correlation between inter-ecotype similarity matrices based on methylation-insensitive or methylation-sensitive polymorphisms suggests that whatever the mechanisms regulating methylation may be, they are not related to nucleotide sequence variation.

  7. Recognition of methylated DNA through methyl-CpG binding domain proteins

    DEFF Research Database (Denmark)

    Zou, Xueqing; Ma, Wen; Solov'yov, Ilia

    2012-01-01

    DNA methylation is a key regulatory control route in epigenetics, involving gene silencing and chromosome inactivation. It has been recognized that methyl-CpG binding domain (MBD) proteins play an important role in interpreting the genetic information encoded by methylated DNA (mDNA). Although...... the function of MBD proteins has attracted considerable attention and is well characterized, the mechanism underlying mDNA recognition by MBD proteins is still poorly understood. In this article, we demonstrate that the methyl-CpG dinucleotides are recognized at the MBD-mDNA interface by two MBD arginines...

  8. Maternal intake of methyl-group donors affects DNA methylation of metabolic genes in infants.

    Science.gov (United States)

    Pauwels, Sara; Ghosh, Manosij; Duca, Radu Corneliu; Bekaert, Bram; Freson, Kathleen; Huybrechts, Inge; Langie, Sabine A S; Koppen, Gudrun; Devlieger, Roland; Godderis, Lode

    2017-01-01

    Maternal nutrition during pregnancy and infant nutrition in the early postnatal period (lactation) are critically involved in the development and health of the newborn infant. The Maternal Nutrition and Offspring's Epigenome (MANOE) study was set up to assess the effect of maternal methyl-group donor intake (choline, betaine, folate, methionine) on infant DNA methylation. Maternal intake of dietary methyl-group donors was assessed using a food-frequency questionnaire (FFQ). Before and during pregnancy, we evaluated maternal methyl-group donor intake through diet and supplementation (folic acid) in relation to gene-specific ( IGF2 DMR, DNMT1 , LEP , RXRA ) buccal epithelial cell DNA methylation in 6 months old infants ( n  = 114) via pyrosequencing. In the early postnatal period, we determined the effect of maternal choline intake during lactation (in mothers who breast-fed for at least 3 months) on gene-specific buccal DNA methylation ( n  = 65). Maternal dietary and supplemental intake of methyl-group donors (folate, betaine, folic acid), only in the periconception period, was associated with buccal cell DNA methylation in genes related to growth ( IGF2 DMR), metabolism ( RXRA ), and appetite control ( LEP ). A negative association was found between maternal folate and folic acid intake before pregnancy and infant LEP (slope = -1.233, 95% CI -2.342; -0.125, p  = 0.0298) and IGF2 DMR methylation (slope = -0.706, 95% CI -1.242; -0.107, p  = 0.0101), respectively. Positive associations were observed for maternal betaine (slope = 0.875, 95% CI 0.118; 1.633, p  = 0.0241) and folate (slope = 0.685, 95% CI 0.245; 1.125, p  = 0.0027) intake before pregnancy and RXRA methylation. Buccal DNMT1 methylation in the infant was negatively associated with maternal methyl-group donor intake in the first and second trimester of pregnancy and negatively in the third trimester. We found no clear association between maternal choline intake

  9. Methyl Iodide Decomposition at BWR Conditions

    International Nuclear Information System (INIS)

    Pop, Mike; Bell, Merl

    2012-09-01

    Based on favourable results from short-term testing of methanol addition to an operating BWR plant, AREVA has performed numerous studies in support of necessary Engineering and Plant Safety Evaluations prior to extended injection of methanol. The current paper presents data from a study intended to provide further understanding of the decomposition of methyl iodide as it affects the assessment of methyl iodide formation with the application of methanol at BWR Plants. This paper describes the results of the decomposition testing under UV-C light at laboratory conditions and its effect on the subject methyl iodide production evaluation. The study as to the formation and decomposition of methyl iodide as it is effected by methanol addition is one phase of a larger AREVA effort to provide a generic plant Safety Evaluation prior to long-term methanol injection to an operating BWR. Other testing phases have investigated the compatibility of methanol with fuel construction materials, plant structural materials, plant consumable materials (i.e. elastomers and coatings), and ion exchange resins. Methyl iodide is known to be very unstable, typically preserved with copper metal or other stabilizing materials when produced and stored. It is even more unstable when exposed to light, heat, radiation, and water. Additionally, it is known that methyl iodide will decompose radiolytically, and that this effect may be simulated using ultra-violet radiation (UV-C) [2]. In the tests described in this paper, the use of a UV-C light source provides activation energy for the formation of methyl iodide. Thus is similar to the effect expected from Cherenkov radiation present in a reactor core after shutdown. Based on the testing described in this paper, it is concluded that injection of methanol at concentrations below 2.5 ppm in BWR applications to mitigate IGSCC of internals is inconsequential to the accident conditions postulated in the FSAR as they are related to methyl iodide formation

  10. Whole genome DNA methylation: beyond genes silencing

    OpenAIRE

    Tirado-Magallanes, Roberto; Rebbani, Khadija; Lim, Ricky; Pradhan, Sriharsa; Benoukraf, Touati

    2016-01-01

    The combination of DNA bisulfite treatment with high-throughput sequencing technologies has enabled investigation of genome-wide DNA methylation at near base pair level resolution, far beyond that of the kilobase-long canonical CpG islands that initially revealed the biological relevance of this covalent DNA modification. The latest high-resolution studies have revealed a role for very punctual DNA methylation in chromatin plasticity, gene regulation and splicing. Here, we aim to outline the ...

  11. DNA methylation abnormalities in congenital heart disease.

    Science.gov (United States)

    Serra-Juhé, Clara; Cuscó, Ivon; Homs, Aïda; Flores, Raquel; Torán, Núria; Pérez-Jurado, Luis A

    2015-01-01

    Congenital heart defects represent the most common malformation at birth, occurring also in ∼50% of individuals with Down syndrome. Congenital heart defects are thought to have multifactorial etiology, but the main causes are largely unknown. We have explored the global methylation profile of fetal heart DNA in comparison to blood DNA from control subjects: an absolute correlation with the type of tissue was detected. Pathway analysis revealed a significant enrichment of differential methylation at genes related to muscle contraction and cardiomyopathies in the developing heart DNA. We have also searched for abnormal methylation profiles on developing heart-tissue DNA of syndromic and non-syndromic congenital heart defects. On average, 3 regions with aberrant methylation were detected per sample and 18 regions were found differentially methylated between groups. Several epimutations were detected in candidate genes involved in growth regulation, apoptosis and folate pathway. A likely pathogenic hypermethylation of several intragenic sites at the MSX1 gene, involved in outflow tract morphogenesis, was found in a fetus with isolated heart malformation. In addition, hypermethylation of the GATA4 gene was present in fetuses with Down syndrome with or without congenital heart defects, as well as in fetuses with isolated heart malformations. Expression deregulation of the abnormally methylated genes was detected. Our data indicate that epigenetic alterations of relevant genes are present in developing heart DNA in fetuses with both isolated and syndromic heart malformations. These epimutations likely contribute to the pathogenesis of the malformation by cis-acting effects on gene expression.

  12. Methylated spirit burns: an ongoing problem.

    Science.gov (United States)

    Jansbeken, J R H; Vloemans, A F P M; Tempelman, F R H; Breederveld, R S

    2012-09-01

    Despite many educational campaigns we still see burns caused by methylated spirit every year. We undertook a retrospective study to analyse the impact of this problem. We retrospectively collected data of all patients with burns caused by methylated spirit over twelve years from 1996 to 2008. Our main endpoints were: incidence, age, mechanism of injury, total body surface area (TBSA) burned, burn depth, need for surgery and length of hospital stay. Ninety-seven patients with methylated spirit burns were included. During the study period there was no decrease in the number of patients annually admitted to the burn unit with methylated spirit burns. 28% of the patients (n=27) were younger than eighteen years old, 15% (n=15) were ten years old or younger. The most common cause of burns was carelessness in activities involving barbecues, campfires and fondues. Mean TBSA burned was 16% (SD 12.4). 70% (n=68) had full thickness burns. 66% (n=64) needed grafting. Mean length of hospital stay was 23 days (SD 24.7). The use of methylated spirit is an ongoing problem, which continues to cause severe burns in adults and children. Therefore methylated spirit should be banned in households. We suggest sale only in specialised shops, clear labelling and mandatory warnings. Copyright © 2012 Elsevier Ltd and ISBI. All rights reserved.

  13. DNA Methylation Biomarkers: Cancer and Beyond

    Directory of Open Access Journals (Sweden)

    Thomas Mikeska

    2014-09-01

    Full Text Available Biomarkers are naturally-occurring characteristics by which a particular pathological process or disease can be identified or monitored. They can reflect past environmental exposures, predict disease onset or course, or determine a patient’s response to therapy. Epigenetic changes are such characteristics, with most epigenetic biomarkers discovered to date based on the epigenetic mark of DNA methylation. Many tissue types are suitable for the discovery of DNA methylation biomarkers including cell-based samples such as blood and tumor material and cell-free DNA samples such as plasma. DNA methylation biomarkers with diagnostic, prognostic and predictive power are already in clinical trials or in a clinical setting for cancer. Outside cancer, strong evidence that complex disease originates in early life is opening up exciting new avenues for the detection of DNA methylation biomarkers for adverse early life environment and for estimation of future disease risk. However, there are a number of limitations to overcome before such biomarkers reach the clinic. Nevertheless, DNA methylation biomarkers have great potential to contribute to personalized medicine throughout life. We review the current state of play for DNA methylation biomarkers, discuss the barriers that must be crossed on the way to implementation in a clinical setting, and predict their future use for human disease.

  14. Oxidation state specific generation of arsines from methylated arsenicals based on L-cysteine treatment in buffered media for speciation analysis by hydride generation-automated cryotrapping-gas chromatography-atomic absorption spectrometry with the multiatomizer

    Energy Technology Data Exchange (ETDEWEB)

    Matousek, Tomas [Institute of Analytical Chemistry of the ASCR, v.v.i., Videnska 1083, 14220 Prague (Czech Republic)], E-mail: matousek@biomed.cas.cz; Hernandez-Zavala, Araceli [Center for Environmental Medicine, Asthma, and Lung Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599-7310 (United States); Svoboda, Milan; Langrova, Lenka [Institute of Analytical Chemistry of the ASCR, v.v.i., Videnska 1083, 14220 Prague (Czech Republic); Charles University, Faculty of Science, Albertov 8, 12840 Prague 2 (Czech Republic); Adair, Blakely M. [Pharmacokinetics Branch, Experimental Toxicology Division, National Health and Environmental Effects Laboratory, Office of Research and Development, U.S. Environmental Protection Agency, Research Triangle Park, NC 27711 (United States); Drobna, Zuzana [Department of Nutrition, School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599-7461 (United States); Thomas, David J. [Pharmacokinetics Branch, Experimental Toxicology Division, National Health and Environmental Effects Laboratory, Office of Research and Development, U.S. Environmental Protection Agency, Research Triangle Park, NC 27711 (United States); Styblo, Miroslav [Center for Environmental Medicine, Asthma, and Lung Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599-7310 (United States); Department of Nutrition, School of Medicine, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599-7461 (United States); Dedina, Jiri [Institute of Analytical Chemistry of the ASCR, v.v.i., Videnska 1083, 14220 Prague (Czech Republic)

    2008-03-15

    An automated system for hydride generation-cryotrapping-gas chromatography-atomic absorption spectrometry with the multiatomizer is described. Arsines are preconcentrated and separated in a Chromosorb filled U-tube. An automated cryotrapping unit, employing nitrogen gas formed upon heating in the detection phase for the displacement of the cooling liquid nitrogen, has been developed. The conditions for separation of arsines in a Chromosorb filled U-tube have been optimized. A complete separation of signals from arsine, methylarsine, dimethylarsine, and trimethylarsine has been achieved within a 60 s reading window. The limits of detection for methylated arsenicals tested were 4 ng l{sup -1}. Selective hydride generation is applied for the oxidation state specific speciation analysis of inorganic and methylated arsenicals. The arsines are generated either exclusively from trivalent or from both tri- and pentavalent inorganic and methylated arsenicals depending on the presence of L-cysteine as a prereductant and/or reaction modifier. A TRIS buffer reaction medium is proposed to overcome narrow optimum concentration range observed for the L-cysteine modified reaction in HCl medium. The system provides uniform peak area sensitivity for all As species. Consequently, the calibration with a single form of As is possible. This method permits a high-throughput speciation analysis of metabolites of inorganic arsenic in relatively complex biological matrices such as cell culture systems without sample pretreatment, thus preserving the distribution of tri- and pentavalent species.

  15. Complexation thermodynamics and structural studies of trivalent actinide and lanthanide complexes with DTPA, MS-325 and HMDTPA

    Energy Technology Data Exchange (ETDEWEB)

    Thakur, P.; Choppin, G.R. [Florida State Univ., Tallahassee, FL (United States). Dept. of Chemistry and Biochemistry; Conca, J.L. [RJ Lee Group, Inc., Pasco, WA (United States). Center for Lab. Sciences; Dodge, C.J. [Brookhaven National Laboratory, Upton, NY (United States); Francis, A.J. [Brookhaven National Laboratory, Upton, NY (United States); Pohang Univ. of Science and Technology (Korea, Republic of). Div. of Advanced Nuclear Engineering

    2013-05-01

    The protonation constants of DTPA (diethylenetriaminepentaacetic acid) and two derivatives of DTPA, 1-R(4,4-diphenyl cyclohexyl-phosphonyl-methyl diethylenentriaminepentaacetic acid) (MS-325) and (R)-hydroxymethyl-diethylenentriaminepentaacetic acid (HMDTPA) were determined by potentiometric titration in 0.1 M NaClO{sub 4}. The formation of 1: 1 complexes of Am{sup 3+}, Cm{sup 3+} and Ln{sup 3+} cations with these three ligands were investigated by potentiometric titration with competition by ethylenediaminetetraacetic acid (EDTA) and the solvent extraction method in aqueous solutions of I=0.10 M NaClO{sub 4}. The thermodynamic data of complexation were determined by the temperature dependence of the stability constants and by calorimetry. The complexation is exothermic and becomes weaker with increase in temperature. The complexation strength of these ligands follows the order: DTPA {approx} HMDTPA > MS-325. Eu{sup 3+}/Cm{sup 3+} luminescence, EXAFS (Extended X-ray Absorption Fine Structure) and DFT (Density Functional Theory) calculations suggest that all three ligands are octadentate in the complex. In the complex, M(L){sup 2-} (L = DTPA, MS-325 and HMDTPA). The M{sup 3+} binds via five carboxylates oxygen atoms, three nitrogen atoms, and the complex contains one water of hydration. (orig.)

  16. Robertsonian chromosome polymorphism of Akodon molinae (Rodentia: Sigmodontinae: analysis of trivalents in meiotic prophase Polimorfismo cromosómico Robertsoniano de Akodon molinae (Rodentia: Sigmodontinae

    Directory of Open Access Journals (Sweden)

    RAÚL FERNÁNDEZ-DONOSO

    2001-03-01

    Full Text Available Akodon molinae (with 2n = 42-43-44 and an FN = 44 shows a remarkable polymorphism of chromosome 1 in natural and laboratory populations. Specimens 2n = 42, named single homozygotes (SH, have a chromosome pair 1 formed by two large metacentric chromosomes. Specimens 2n = 3, heterozygotes (Ht, have one chromosome 1 and two medium-sized subtelocentric chromosomes, 1a and 1b, which are homologous with the long and short arms of chromosome 1 respectively. Specimens 2n = 44 are double homozygotes (DH, with just two pairs of medium-sized subtelocentric chromosomes, 1a and 1b. Analysis of meiotic metaphases I and II showed that anomalous segregation occurs more frequently in spermatocytes carrying the 1a and 1b chromosomes. This would disturb gametogenesis and other reproductive and developmental processes, producing a marked decrease in viability of DH individuals. There is, as yet, no satisfactory explanation for these phenomena. To investigate structural elements which might explain such segregational anomalies, we have studied bivalent and trivalent synapsis in pachytene spermatocytes from SH, Ht and DH specimens. Of a total of 80 spermatocyte nuclei microspreads, the following results were obtained: of 16 microspreads from two SH individuals, 20 autosomic bivalents plus the XY bivalent were observed; of 48 microspreads from three Ht individuals, 19 autosomic bivalents, 1 trivalent and an XY bivalent were seen; and of the 16 microspreads from two DH individuals, 21 autosomic bivalents plus the XY bivalent were found. Trivalents analysed showed complete pairing between the short arms of 1a and 1b, and having an apparently normal synaptonemal complex (SC with lengths of 1 and 2.8 µm. The trivalent SC showed three telomeric ends, corresponding to arms: q1 and q1a; p1 and q1b; and p1a and p1b, with attachment plates to the nuclear envelope of normal organisation. None of the trivalents showed asynapsis or desynapsis between p1a and p1b, nor an

  17. Reactions of guanine with methyl chloride and methyl bromide: O6-methylation versus charge transfer complex formation

    Science.gov (United States)

    Shukla, P. K.; Mishra, P. C.; Suhai, S.

    Density functional theory (DFT) at the B3LYP/6-31+G* and B3LYP/AUG-cc-pVDZ levels was employed to study O6-methylation of guanine due to its reactions with methyl chloride and methyl bromide and to obtain explanation as to why the methyl halides cause genotoxicity and possess mutagenic and carcinogenic properties. Geometries of the various isolated species involved in the reactions, reactant complexes (RCs), and product complexes (PCs) were optimized in gas phase. Transition states connecting the reactant complexes with the product complexes were also optimized in gas phase at the same levels of theory. The reactant complexes, product complexes, and transition states were solvated in aqueous media using the polarizable continuum model (PCM) of the self-consistent reaction field theory. Zero-point energy (ZPE) correction to total energy and the corresponding thermal energy correction to enthalpy were made in each case. The reactant complexes of the keto form of guanine with methyl chloride and methyl bromide in water are appreciably more stable than the corresponding complexes involving the enol form of guanine. The nature of binding in the product complexes was found to be of the charge transfer type (O6mG+ · X-, X dbond Cl, Br). Binding of HCl, HBr, and H2O molecules to the PCs obtained with the keto form of guanine did not alter the positions of the halide anions in the PCs, and the charge transfer character of the PCs was also not modified due to this binding. Further, the complexes obtained due to the binding of HCl, HBr, and H2O molecules to the PCs had greater stability than the isolated PCs. The reaction barriers involved in the formation of PCs were found to be quite high (?50 kcal/mol). Mechanisms of genotoxicity, mutagenesis and carcinogenesis caused by the methyl halides appear to involve charge transfer-type complex formation. Thus the mechanisms of these processes involving the methyl halides appear to be quite different from those that involve the

  18. Global DNA methylation of ischemic stroke subtypes.

    Directory of Open Access Journals (Sweden)

    Carolina Soriano-Tárraga

    Full Text Available Ischemic stroke (IS, a heterogeneous multifactorial disorder, is among the leading causes of mortality and long-term disability in the western world. Epidemiological data provides evidence for a genetic component to the disease, but its epigenetic involvement is still largely unknown. Epigenetic mechanisms, such as DNA methylation, change over time and may be associated with aging processes and with modulation of the risk of various pathologies, such as cardiovascular disease and stroke. We analyzed 2 independent cohorts of IS patients. Global DNA methylation was measured by luminometric methylation assay (LUMA of DNA blood samples. Univariate and multivariate regression analyses were used to assess the methylation differences between the 3 most common IS subtypes, large-artery atherosclerosis (LAA, small-artery disease (SAD, and cardio-aortic embolism (CE. A total of 485 IS patients from 2 independent hospital cohorts (n = 281 and n = 204 were included, distributed across 3 IS subtypes: LAA (78/281, 59/204, SAD (97/281, 53/204, and CE (106/281, 89/204. In univariate analyses, no statistical differences in LUMA levels were observed between the 3 etiologies in either cohort. Multivariate analysis, adjusted by age, sex, hyperlipidemia, and smoking habit, confirmed the lack of differences in methylation levels between the analyzed IS subtypes in both cohorts. Despite differences in pathogenesis, our results showed no global methylation differences between LAA, SAD, and CE subtypes of IS. Further work is required to establish whether the epigenetic mechanism of methylation might play a role in this complex disease.

  19. Inductive effect of methyl group in a series of methylated indoles: A ...

    Indian Academy of Sciences (India)

    Vol. 125, No. 4, July 2013, pp. 905–912. c Indian Academy of Sciences. Inductive effect of methyl group in a series of methylated indoles: A graph theoretical analysis in the light of density functional theory and correlation with experimental charge transfer transition energies. AMIT S TIWARYa,∗ and ASOK K MUKHERJEEb.

  20. Evidence for methyl group transfer between the methyl-accepting chemotaxis proteins in Bacillus subtilis

    International Nuclear Information System (INIS)

    Bedale, W.A.; Nettleton, D.O.; Sopata, C.S.; Thoelke, M.S.; Ordal, G.W.

    1988-01-01

    The authors present evidence for methyl (as methyl or methoxy) transfer from the methyl-accepting chemotaxis proteins H1 and possibly H3 of Bacillus subtilis to the methyl-accepting chemotaxis protein H2. This methyl transfer, which has been observed in vitro was strongly stimulated by the chemoattractant aspartate and thus may plan an important role in the sensory processing system of this organism. Although radiolabeling of H1 and H3 began at once after the addition of [ 3 H] methionine, radiolabeling of H2 showed a lag. Furthermore, the addition of excess nonradioactive methionine caused immediate exponential delabeling of H1 and H3 while labeling of H2 continued to increase. Methylation of H2 required the chemotactic methyltransferase, probably to first methylate H1 and H3. Aspartate caused increased labeling of H2 and strongly decreased labeling of H1 and H3 after the addition of nonradioactive methionine. Without the addition of nonradioactive methionine, aspartate caused demethylation of H1 and to a lesser extent H3, with an approximately equal increase of methylation of H2

  1. Methyl esters from vegetable oils with hydroxy fatty acids: Comparison of lesquerella and castor methyl esters

    Science.gov (United States)

    The search for alternative feedstocks for biodiesel as partial replacement for petrodiesel has recently extended to castor oil. In this work, the castor oil methyl esters were prepared and their properties determined in comparison to the methyl esters of lesquerella oil, which in turn is seen as alt...

  2. Identification of arsenite-and arsenic diglutathione-binding proteins in human hepatocarcinoma cells

    Energy Technology Data Exchange (ETDEWEB)

    Mizumura, Ayano; Watanabe, Takayuki [Graduate School of Pharmaceutical Sciences, Chiba University, Yayoi, Inage, Chiba 263-8522 (Japan); Kobayashi, Yayoi [Graduate School of Pharmaceutical Sciences, Chiba University, Yayoi, Inage, Chiba 263-8522 (Japan); Environmental Health Sciences Division, National Institute for Environmental Studies, 16-2 Onogawa, Tsukuba, Ibaraki 305-8506 (Japan); Hirano, Seishiro [Graduate School of Pharmaceutical Sciences, Chiba University, Yayoi, Inage, Chiba 263-8522 (Japan); Research Center for Environmental Risk, National Institute for Environmental Studies, 16-2 Onogawa, Tsukuba, Ibaraki 305-8506 (Japan)

    2010-01-15

    It is generally accepted that trivalent arsenicals are more toxic than the corresponding pentavalent arsenicals, since trivalent arsenicals bind the thiol groups of biomolecules, leading to a deterioration in cellular functions. In the present study, we prepared three different arsenic-bound sepharoses and investigated the binding of hepatic cytosolic proteins to pentavalent, trivalent, and glutathione-conjugated trivalent arsenicals. SDS-PAGE showed no proteins bound to pentavalent arsenic specifically. In contrast, we found a number of proteins that have specific and high affinity for trivalent arsenic. Two of those proteins were identified: protein disulfide isomerase-related protein 5 (PDSIRP5) and peroxiredoxin 1/enhancer protein (PRX1/EP). These proteins have vicinal cysteines, as previously reported. In contrast, one of the prominent proteins that did not bind to trivalent arsenic was identified as calreticulin precursor. Although there are 3 cysteines in calreticulin precursor, two of the cysteines are spaced more than 25 amino acids apart. Five synthetic peptides containing 2 vicinal cysteines were prepared to study whether they would inhibit the binding of PDSIRP5, PRX1/EP, and other arsenic-binding proteins to trivalent arsenicals. Only two of the five peptides effectively inhibited binding, suggesting that other amino acids besides the 2 vicinal cysteines may modulate the affinity of cysteine-rich proteins for trivalent arsenicals. We further investigated hepatic cytosolic proteins that bound specifically to glutathione-conjugated trivalent arsenic, which is the most abundant form of arsenical in bile fluid. Four proteins that bound specifically to glutathione-conjugated trivalent arsenic were identified; interestingly, these proteins were different from the trivalent arsenic-binding proteins. These results suggest that although glutathione-conjugation is an important process in the metabolism, excretion, and detoxification of arsenicals, glutathione

  3. Modeling of the oxidation of methyl esters—Validation for methyl hexanoate, methyl heptanoate, and methyl decanoate in a jet-stirred reactor

    Science.gov (United States)

    Glaude, Pierre Alexandre; Herbinet, Olivier; Bax, Sarah; Biet, Joffrey; Warth, Valérie; Battin-Leclerc, Frédérique

    2013-01-01

    The modeling of the oxidation of methyl esters was investigated and the specific chemistry, which is due to the presence of the ester group in this class of molecules, is described. New reactions and rate parameters were defined and included in the software EXGAS for the automatic generation of kinetic mechanisms. Models generated with EXGAS were successfully validated against data from the literature (oxidation of methyl hexanoate and methyl heptanoate in a jet-stirred reactor) and a new set of experimental results for methyl decanoate. The oxidation of this last species was investigated in a jet-stirred reactor at temperatures from 500 to 1100 K, including the negative temperature coefficient region, under stoichiometric conditions, at a pressure of 1.06 bar and for a residence time of 1.5 s: more than 30 reaction products, including olefins, unsaturated esters, and cyclic ethers, were quantified and successfully simulated. Flow rate analysis showed that reactions pathways for the oxidation of methyl esters in the low-temperature range are similar to that of alkanes. PMID:23710076

  4. Modeling of the oxidation of methyl esters-Validation for methyl hexanoate, methyl heptanoate, and methyl decanoate in a jet-stirred reactor.

    Science.gov (United States)

    Glaude, Pierre Alexandre; Herbinet, Olivier; Bax, Sarah; Biet, Joffrey; Warth, Valérie; Battin-Leclerc, Frédérique

    2010-11-01

    The modeling of the oxidation of methyl esters was investigated and the specific chemistry, which is due to the presence of the ester group in this class of molecules, is described. New reactions and rate parameters were defined and included in the software EXGAS for the automatic generation of kinetic mechanisms. Models generated with EXGAS were successfully validated against data from the literature (oxidation of methyl hexanoate and methyl heptanoate in a jet-stirred reactor) and a new set of experimental results for methyl decanoate. The oxidation of this last species was investigated in a jet-stirred reactor at temperatures from 500 to 1100 K, including the negative temperature coefficient region, under stoichiometric conditions, at a pressure of 1.06 bar and for a residence time of 1.5 s: more than 30 reaction products, including olefins, unsaturated esters, and cyclic ethers, were quantified and successfully simulated. Flow rate analysis showed that reactions pathways for the oxidation of methyl esters in the low-temperature range are similar to that of alkanes.

  5. Histone Lysine Methylation in Diabetic Nephropathy

    Directory of Open Access Journals (Sweden)

    Guang-dong Sun

    2014-01-01

    Full Text Available Diabetic nephropathy (DN belongs to debilitating microvascular complications of diabetes and is the leading cause of end-stage renal diseases worldwide. Furthermore, outcomes from the DCCT/EDIC study showed that DN often persists and progresses despite intensive glucose control in many diabetes patients, possibly as a result of prior episode of hyperglycemia, which is called “metabolic memory.” The underlying mechanisms responsible for the development and progression of DN remain poorly understood. Activation of multiple signaling pathways and key transcription factors can lead to aberrant expression of DN-related pathologic genes in target renal cells. Increasing evidence suggests that epigenetic mechanisms in chromatin such as DNA methylation, histone acetylation, and methylation can influence the pathophysiology of DN and metabolic memory. Exciting researches from cell culture and experimental animals have shown that key histone methylation patterns and the related histone methyltransferases and histone demethylases can play important roles in the regulation of inflammatory and profibrotic genes in renal cells under diabetic conditions. Because histone methylation is dynamic and potentially reversible, it can provide a window of opportunity for the development of much-needed novel therapeutic potential for DN in the future. In this minireview, we discuss recent advances in the field of histone methylation and its roles in the pathogenesis and progression of DN.

  6. Prognostic DNA Methylation Markers for Prostate Cancer

    Directory of Open Access Journals (Sweden)

    Siri H. Strand

    2014-09-01

    Full Text Available Prostate cancer (PC is the most commonly diagnosed neoplasm and the third most common cause of cancer-related death amongst men in the Western world. PC is a clinically highly heterogeneous disease, and distinction between aggressive and indolent disease is a major challenge for the management of PC. Currently, no biomarkers or prognostic tools are able to accurately predict tumor progression at the time of diagnosis. Thus, improved biomarkers for PC prognosis are urgently needed. This review focuses on the prognostic potential of DNA methylation biomarkers for PC. Epigenetic changes are hallmarks of PC and associated with malignant initiation as well as tumor progression. Moreover, DNA methylation is the most frequently studied epigenetic alteration in PC, and the prognostic potential of DNA methylation markers for PC has been demonstrated in multiple studies. The most promising methylation marker candidates identified so far include PITX2, C1orf114 (CCDC181 and the GABRE~miR-452~miR-224 locus, in addition to the three-gene signature AOX1/C1orf114/HAPLN3. Several other biomarker candidates have also been investigated, but with less stringent clinical validation and/or conflicting evidence regarding their possible prognostic value available at this time. Here, we review the current evidence for the prognostic potential of DNA methylation markers in PC.

  7. Methylated genes as new cancer biomarkers

    DEFF Research Database (Denmark)

    Brunner, Nils; Duffy, M.J; Napieralski, R.

    2009-01-01

    Aberrant hypermethylation of promoter regions in specific genes is a key event in the formation and progression of cancer. In at least some situations, these aberrant alterations occur early in the formation of malignancy and appear to be tumour specific. Multiple reports have suggested that meas......Aberrant hypermethylation of promoter regions in specific genes is a key event in the formation and progression of cancer. In at least some situations, these aberrant alterations occur early in the formation of malignancy and appear to be tumour specific. Multiple reports have suggested...... that measurement of the methylation status of the promoter regions of specific genes can aid early detection of cancer, determine prognosis and predict therapy responses. Promising DNA methylation biomarkers include the use of methylated GSTP1 for aiding the early diagnosis of prostate cancer, methylated PITX2...... for predicting outcome in lymph node-negative breast cancer patients and methylated MGMT in predicting benefit from alkylating agents in patients with glioblastomas. However, prior to clinical utilisation, these findings require validation in prospective clinical studies. Furthermore, assays for measuring gene...

  8. Dynamic Alu Methylation during Normal Development, Aging, and Tumorigenesis

    Directory of Open Access Journals (Sweden)

    Yanting Luo

    2014-01-01

    Full Text Available DNA methylation primarily occurs on CpG dinucleotides and plays an important role in transcriptional regulations during tissue development and cell differentiation. Over 25% of CpG dinucleotides in the human genome reside within Alu elements, the most abundant human repeats. The methylation of Alu elements is an important mechanism to suppress Alu transcription and subsequent retrotransposition. Decades of studies revealed that Alu methylation is highly dynamic during early development and aging. Recently, many environmental factors were shown to have a great impact on Alu methylation. In addition, aberrant Alu methylation has been documented to be an early event in many tumors and Alu methylation levels have been associated with tumor aggressiveness. The assessment of the Alu methylation has become an important approach for early diagnosis and/or prognosis of cancer. This review focuses on the dynamic Alu methylation during development, aging, and tumor genesis. The cause and consequence of Alu methylation changes will be discussed.

  9. Developmental differences in posttranslational calmodulin methylation in pea plants

    International Nuclear Information System (INIS)

    Oh, Sukheung; Roberts, D.M.

    1990-01-01

    A calmodulin-N-methyltransferase was used to analyze the degree of lysine-115 methylation of pea calmodulin. Calmodulin was isolated from segments of developing roots of young etiolated and green pea plants and was tested for its ability to be methylated by the calmodulin methyltransferase in the presence of 3 H-methyl-S-adenosylmethionine. Calmodulin methylation levels were lower in apical root segments and in the young lateral roots compared with the mature, differentiated root tissues. The methylation of these calmodulin samples occurs specifically at lysine 115 since site-directed mutants of calmodulin with substitutions at this position were not methylated and competitively inhibited methylation. The present findings, combined with previous data showing differences in NAD kinase activation by methylated and unmethylated calmodulins, raise the possibility that posttranslational methylation could affect calmodulin action

  10. Influence of metal loading and humic acid functional groups on the complexation behavior of trivalent lanthanides analyzed by CE-ICP-MS

    Energy Technology Data Exchange (ETDEWEB)

    Kautenburger, Ralf, E-mail: r.kautenburger@mx.uni-saarland.de [Institute of Inorganic Solid State Chemistry, Saarland University, Campus Dudweiler, Am Markt Zeile 3-5, D-66125 Saarbrücken (Germany); Hein, Christina; Sander, Jonas M. [Institute of Inorganic Solid State Chemistry, Saarland University, Campus Dudweiler, Am Markt Zeile 3-5, D-66125 Saarbrücken (Germany); Beck, Horst P. [Institute of Inorganic and Analytical Chemistry and Radiochemistry, Saarland University, Campus Dudweiler, Am Markt Zeile 5, D-66125 Saarbrücken (Germany)

    2014-03-01

    Highlights: • Free and complexed HA-Ln species are separated by CE-ICP-MS. • Weaker and stronger HA-binding sites for Ln-complexation can be detected. • Complexation by original and modified humic acid (HA) with blocked phenolic hydroxyl- and carboxyl-groups is compared. • Stronger HA-binding sites for Ln³⁺ can be assumed as chelating complexes. • Chelates consist of trivalent Ln and a combination of both OH- and COOH-groups. Abstract: The complexation behavior of Aldrich humic acid (AHA) and a modified humic acid (AHA-PB) with blocked phenolic hydroxyl groups for trivalent lanthanides (Ln) is compared, and their influence on the mobility of Ln(III) in an aquifer is analyzed. As speciation technique, capillary electrophoresis (CE) was hyphenated with inductively coupled plasma mass spectrometry (ICP-MS). For metal loading experiments 25 mg L⁻¹ of AHA and different concentrations (c Ln(Eu+Gd)} = 100–6000 μg L⁻¹) of Eu(III) and Gd(III) in 10 mM NaClO₄ at pH 5 were applied. By CE-ICP-MS, three Ln-fractions, assumed to be uncomplexed, weakly and strongly AHA-complexed metal can be detected. For the used Ln/AHA-ratios conservative complex stability constants log βLnAHA decrease from 6.33 (100 μg L⁻¹ Ln³⁺) to 4.31 (6000 μg L⁻¹ Ln³⁺) with growing Ln-content. In order to verify the postulated weaker and stronger humic acid binding sites for trivalent Eu and Gd, a modified AHA with blocked functional groups was used. For these experiments 500 μg L⁻¹ Eu and 25 mg L⁻¹ AHA and AHA-PB in 10 mM NaClO₄ at pH-values ranging from 3 to 10 have been applied. With AHA-PB, where 84% of the phenolic OH-groups and 40% of the COOH-groups were blocked, Eu complexation was significantly lower, especially at the strong binding sites. The log β-values decrease from 6.11 (pH 10) to 5.61 at pH 3 (AHA) and for AHA-PB from 6.01 (pH 7) to 3.94 at pH 3. As a potential consequence, particularly humic acids with a high amount of

  11. Methylated liquor treatment process in caffeine production

    Science.gov (United States)

    Zhou, Junbo; Yang, Mingyang; Huang, Wenjia; Cui, Shenglu; Gao, Liping

    2018-02-01

    The caffeine production process produces a large amount of sodium methyl sulphate in the methylated mother liquor. In order to recycle this part of ingredient, we use the mother liquid of Shijiazhuang Xin Nuowei Pharmaceutical Co., Ltd. as the object of study, the use of “nanofiltration (NF) - Dish Type Reverse Osmosis (DTRO) “combination of membrane technology for desalination and concentration. The experimental results show that the concentration of sodium sulfate in the nanofiltration solution is 0.37 g • L -1, the rejection rate is 98%, and the concentration of sodium methyl sulfate in DTRO concentrated solution is 453.80 g • L -1, which meets the requirements of the enterprise.

  12. Histone H4 Lysine 20 methylation

    DEFF Research Database (Denmark)

    Jørgensen, Stine; Schotta, Gunnar; Sørensen, Claus Storgaard

    2013-01-01

    of histones have emerged as key regulators of genomic integrity. Intense research during the past few years has revealed histone H4 lysine 20 methylation (H4K20me) as critically important for the biological processes that ensure genome integrity, such as DNA damage repair, DNA replication and chromatin...... compaction. The distinct H4K20 methylation states are mediated by SET8/PR-Set7 that catalyses monomethylation of H4K20, whereas SUV4-20H1 and SUV4-20H2 enzymes mediate further H4K20 methylation to H4K20me2 and H4K20me3. Disruption of these H4K20-specific histone methyltransferases leads to genomic...

  13. Observational safety study of specific outcomes after trivalent cell culture seasonal influenza vaccination (Optaflu® ) among adults in THIN database of electronic UK primary healthcare records.

    Science.gov (United States)

    Hall, Gillian C; Davies, Paul T G; Karim, M Yousuf; Haag, Mendel D M; O'Leary, Caroline

    2018-01-01

    To investigate the safety of trivalent seasonal influenza vaccine (TIVc) (Optaflu ® ), the first cell culture seasonal trivalent influenza vaccine available in Europe. Codes and unstructured text in adult electronic healthcare records (The Health Improvement Network) were searched for a TIVc brand name or batch number and possible outcomes within a 3 month pre- to 6 month post-TIVc exposure study period (2012-2015). The outcomes were severe allergic reactions, Bell's palsy, convulsions, demyelination, paresthesia, noninfectious encephalitis, neuritis (optic and brachial), vasculitis, inflammatory bowel disease, and thrombocytopenia. Risk periods were defined based on biologically plausible time frame postvaccination when an outcome caused by the vaccine might be expected to occur. Possible outcomes were adjudicated against outcome specific case definitions and a date of onset assigned by using electronic and other medical records. Observed (risk period) to expected (outside risk and preexposure periods) rate ratios, postexposure incidence, and plots of time from exposure to outcome were reported. Sixteen of 1011 events from 4578 exposures fulfilled a primary case definition and had a date of onset during the study period. Three were in observed time. The observed-to-expected rate ratios were (3.3, 95% CI 0.3, 31.7) for convulsions and (1.5, 95% CI 0.2, 14.9) for thrombocytopenia with 1 outcome each in observed time. There was 1 incident inflammatory bowel disease in observed, but none in expected, time. The small sample size restricts interpretation; however, no hypothesis of an increased risk of a study outcome was generated. Adjudication of events against case definitions to reduce misclassification of onset and outcomes allowed use of precise risk periods. KEY POINTS This observational study did not generate a hypothesis of an association between the first cell-culture seasonal influenza vaccination available in the European Union and any of the study

  14. A new trivalent SnSAG surface antigen chimera for efficient detection of antibodies against Sarcocystis neurona and diagnosis of equine protozoal myeloencephalitis.

    Science.gov (United States)

    Yeargan, Michelle; de Assis Rocha, Izabela; Morrow, Jennifer; Graves, Amy; Reed, Stephen M; Howe, Daniel K

    2015-05-01

    Enzyme-linked immunosorbent assays (ELISAs) based on the SnSAG surface antigens of Sarcocystis neurona provide reliable detection of infection by the parasite. Moreover, accurate serodiagnosis of equine protozoal myeloencephalitis (EPM) is achieved with the SnSAG ELISAs by measuring antibodies in serum and cerebrospinal fluid (CSF) to reveal active infection in the central nervous system. Two independent ELISAs based on recombinant (r)SnSAG2 or a chimeric fusion of SnSAG3 and SnSAG4 (rSnSAG4/3) are currently used together for EPM serodiagnosis to overcome varied antibody responses in different horses. To achieve reliable antibody detection with a single ELISA instead of 2 separate ELISAs, rSnSAG2 was fused with rSnSAG4/3 into a single trivalent protein, designated rSnSAG2/4/3. Paired serum and CSF from 163 horses were tested with all 3 ELISAs. When the consensus antibody titers obtained with the rSnSAG2 and rSnSAG4/3 ELISAs were compared to the single SAG2/4/3 ELISA titers, Spearman rank correlation coefficients of ρ = 0.74 and ρ = 0.90 were obtained for serum and CSF, respectively, indicating strong agreement between the tests. When the rSnSAG2 and rSnSAG4/3 consensus serum-to-CSF titer ratio was compared to the rSnSAG2/4/3 serum-to-CSF titer ratio, the Spearman correlation coefficient was ρ = 0.87, again signifying strong agreement. Importantly, comparing the diagnostic interpretation of the serum-to-CSF titer ratios yielded a Cohen kappa value of 0.77. These findings suggest that the single ELISA based on the trivalent rSnSAG2/4/3 will provide serologic and diagnostic results that are highly comparable to the consensus of the 2 independent ELISAs based on rSnSAG2 and rSnSAG4/3. © 2015 The Author(s).

  15. Information Thermodynamics of Cytosine DNA Methylation.

    Directory of Open Access Journals (Sweden)

    Robersy Sanchez

    Full Text Available Cytosine DNA methylation (CDM is a stable epigenetic modification to the genome and a widespread regulatory process in living organisms that involves multicomponent molecular machines. Genome-wide cytosine methylation patterning participates in the epigenetic reprogramming of a cell, suggesting that the biological information contained within methylation positions may be amenable to decoding. Adaptation to a new cellular or organismal environment also implies the potential for genome-wide redistribution of CDM changes that will ensure the stability of DNA molecules. This raises the question of whether or not we would be able to sort out the regulatory methylation signals from the CDM background ("noise" induced by thermal fluctuations. Here, we propose a novel statistical and information thermodynamic description of the CDM changes to address the last question. The physical basis of our statistical mechanical model was evaluated in two respects: 1 the adherence to Landauer's principle, according to which molecular machines must dissipate a minimum energy ε = kBT ln2 at each logic operation, where kB is the Boltzmann constant, and T is the absolute temperature and 2 whether or not the binary stretch of methylation marks on the DNA molecule comprise a language of sorts, properly constrained by thermodynamic principles. The study was performed for genome-wide methylation data from 152 ecotypes and 40 trans-generational variations of Arabidopsis thaliana and 93 human tissues. The DNA persistence length, a basic mechanical property altered by CDM, was estimated with values from 39 to 66.9 nm. Classical methylome analysis can be retrieved by applying information thermodynamic modelling, which is able to discriminate signal from noise. Our finding suggests that the CDM signal comprises a language scheme properly constrained by molecular thermodynamic principles, which is part of an epigenomic communication system that obeys the same thermodynamic

  16. DNA methylation and healthy human aging.

    Science.gov (United States)

    Jones, Meaghan J; Goodman, Sarah J; Kobor, Michael S

    2015-12-01

    The process of aging results in a host of changes at the cellular and molecular levels, which include senescence, telomere shortening, and changes in gene expression. Epigenetic patterns also change over the lifespan, suggesting that epigenetic changes may constitute an important component of the aging process. The epigenetic mark that has been most highly studied is DNA methylation, the presence of methyl groups at CpG dinucleotides. These dinucleotides are often located near gene promoters and associate with gene expression levels. Early studies indicated that global levels of DNA methylation increase over the first few years of life and then decrease beginning in late adulthood. Recently, with the advent of microarray and next-generation sequencing technologies, increases in variability of DNA methylation with age have been observed, and a number of site-specific patterns have been identified. It has also been shown that certain CpG sites are highly associated with age, to the extent that prediction models using a small number of these sites can accurately predict the chronological age of the donor. Together, these observations point to the existence of two phenomena that both contribute to age-related DNA methylation changes: epigenetic drift and the epigenetic clock. In this review, we focus on healthy human aging throughout the lifetime and discuss the dynamics of DNA methylation as well as how interactions between the genome, environment, and the epigenome influence aging rates. We also discuss the impact of determining 'epigenetic age' for human health and outline some important caveats to existing and future studies. © 2015 The Authors. Aging Cell published by the Anatomical Society and John Wiley & Sons Ltd.

  17. A novel method to quantify local CpG methylation density by regional methylation elongation assay on microarray

    Directory of Open Access Journals (Sweden)

    Qiao Yingjuan

    2008-01-01

    Full Text Available Abstract Background DNA methylation based techniques are important tools in both clinical diagnostics and therapeutics. But most of these methods only analyze a few CpG sites in a target region. Indeed, difference of site-specific methylation may also lead to a change of methylation density in many cases, and it has been found that the density of methylation is more important than methylation of single CpG site for gene silencing. Results We have developed a novel approach for quantitative analysis of CpG methylation density on the basis of microarray-based hybridization and incorporation of Cy5-dCTP into the Cy3 labeled target DNA by using Taq DNA Polymerase on microarray. The quantification is achieved by measuring Cy5/Cy3 signal ratio which is proportional to methylation density. This methylation-sensitive technique, termed RMEAM (regional methylation elongation assay on microarray, provides several advantages over existing methods used for methylation analysis. It can determine an exact methylation density of the given region, and has potential of high throughput. We demonstrate a use of this method in determining the methylation density of the promoter region of the tumor-related gene MLH1, TERT and MGMT in colorectal carcinoma patients. Conclusion This technique allows for quantitative analysis of regional methylation density, which is the representative of all allelic methylation patterns in the sample. The results show that this technique has the characteristics of simplicity, rapidness, specificity and high-throughput.

  18. Habit modification of nearly perfect single crystals of potassium dihydrogen phosphate (KDP) by trivalent manganese ions studied using synchrotron radiation X-ray multiple diffraction in Renninger scanning mode

    OpenAIRE

    Lai, X; Roberts, KJ; Avanci, LH; Cardoso, LP; Sasaki, JM

    2003-01-01

    The X-ray multiple diffraction technique using synchrotron radiation is applied in the preliminary study of the habit modification of KDP samples as induced by incorporation of the trivalent transition metal cation Mn3+. High-resolution Renninger scans of pure and doped KDP were carried out using 400 as the primary reflection, echoing the fact that these impurity species were segregated in the {100} growth sector. The analysis of the Renninger scans of the doped KDP crystals is consistent wit...

  19. Analysis of DNA Cytosine Methylation Patterns Using Methylation-Sensitive Amplification Polymorphism (MSAP).

    Science.gov (United States)

    Guevara, María Ángeles; de María, Nuria; Sáez-Laguna, Enrique; Vélez, María Dolores; Cervera, María Teresa; Cabezas, José Antonio

    2017-01-01

    Different molecular techniques have been developed to study either the global level of methylated cytosines or methylation at specific gene sequences. One of them is the methylation-sensitive amplified polymorphism technique (MSAP) which is a modification of amplified fragment length polymorphism (AFLP). It has been used to study methylation of anonymous CCGG sequences in different fungi, plants, and animal species. The main variation of this technique resides on the use of isoschizomers with different methylation sensitivity (such as HpaII and MspI) as a frequent-cutter restriction enzyme. For each sample, MSAP analysis is performed using both EcoRI/HpaII- and EcoRI/MspI-digested samples. A comparative analysis between EcoRI/HpaII and EcoRI/MspI fragment patterns allows the identification of two types of polymorphisms: (1) methylation-insensitive polymorphisms that show common EcoRI/HpaII and EcoRI/MspI patterns but are detected as polymorphic amplified fragments among samples and (2) methylation-sensitive polymorphisms which are associated with the amplified fragments that differ in their presence or absence or in their intensity between EcoRI/HpaII and EcoRI/MspI patterns. This chapter describes a detailed protocol of this technique and discusses the modifications that can be applied to adjust the technology to different species of interest.

  20. Trans-methylation reactions in plants: focus on the activated methyl cycle.

    Science.gov (United States)

    Rahikainen, Moona; Alegre, Sara; Trotta, Andrea; Pascual, Jesús; Kangasjärvi, Saijaliisa

    2018-02-01

    Trans-methylation reactions are vital in basic metabolism, epigenetic regulation, RNA metabolism, and posttranslational control of protein function and therefore fundamental in determining the physiological processes in all living organisms. The plant kingdom is additionally characterized by the production of secondary metabolites that undergo specific hydroxylation, oxidation and methylation reactions to obtain a wide array of different chemical structures. Increasing research efforts have started to reveal the enzymatic pathways underlying the biosynthesis of complex metabolites in plants. Further engineering of these enzymatic machineries offers significant possibilities in the development of bio-based technologies, but necessitates deep understanding of their potential metabolic and regulatory interactions. Trans-methylation reactions are tightly coupled with the so-called activated methyl cycle (AMC), an essential metabolic circuit that maintains the trans-methylation capacity in all living cells. Tight regulation of the AMC is crucial in ensuring accurate trans-methylation reactions in different subcellular compartments, cell types, developmental stages and environmental conditions. This review addresses the organization and posttranslational regulation of the AMC and elaborates its critical role in determining metabolic regulation through modulation of methyl utilization in stress-exposed plants. © 2017 Scandinavian Plant Physiology Society.

  1. Origin and fate of 4-methyl steroid hydrocarbons. I. Diagenesis of 4-methyl sterenes

    Energy Technology Data Exchange (ETDEWEB)

    Wolff, G.A.; Lamb, N.A.; Maxwell, J.R.

    1986-03-01

    Treatment of 4-methylcholest-4-ene under mild acid conditions at low temperatures gives chemical evidence for certain features seen in the distributions of sedimentary 4-methyl steroid hydrocarbons, and further indicates that many low temperature diagenetic reactions of steroids are explicable in terms of acid catalyzed rearrangements. Specifically, the results provide: (i) Indirect evidence that the 4-ene skeleton is a key intermediate in the dehydration of 4-methyl stanols in sediments. (ii) An explanation for the distribution of 4-methyl sterenes and A-nor sterenes in the lacustrine Messel shale (Eocene). (iii) An explanation for the presence of 4..beta..-methyl steranes in relatively immature sedimentary rocks, despite the precursor stanols having the 4..cap alpha..-methyl configuration. With increasing maturity in the Paris Basin shales (Lower Toarcian), the less stable 4..beta..-methyl steranes decrease gradually in abundance relative to their 4..cap alpha..-methyl counterparts, at a rate fairly similar to the change in pristane stereochemistry.

  2. Cord blood buffy coat DNA methylation is comparable to whole cord blood methylation.

    Science.gov (United States)

    Dou, John; Schmidt, Rebecca J; Benke, Kelly S; Newschaffer, Craig; Hertz-Picciotto, Irva; Croen, Lisa A; Iosif, Ana-Maria; LaSalle, Janine M; Fallin, M Daniele; Bakulski, Kelly M

    2018-01-01

    Cord blood DNA methylation is associated with numerous health outcomes and environmental exposures. Whole cord blood DNA reflects all nucleated blood cell types, while centrifuging whole blood separates red blood cells, generating a white blood cell buffy coat. Both sample types are used in DNA methylation studies. Cell types have unique methylation patterns and processing can impact cell distributions, which may influence comparability. We evaluated differences in cell composition and DNA methylation between cord blood buffy coat and whole cord blood samples. Cord blood DNA methylation was measured with the Infinium EPIC BeadChip (Illumina) in eight individuals, each contributing buffy coat and whole blood samples. We analyzed principal components (PC) of methylation, performed hierarchical clustering, and computed correlations of mean-centered methylation between pairs. We conducted moderated t-tests on single sites and estimated cell composition. DNA methylation PCs were associated with individual (P PC1 = 1.4 × 10 -9 ; P PC2 = 2.9 × 10 -5 ; P PC3 = 3.8 × 10 -5 ; P PC4 = 4.2 × 10 -6 ; P PC5 = 9.9 × 10 -13 , P PC6 = 1.3 × 10 -11 ) and not with sample type (P PC1-6 >0.7). Samples hierarchically clustered by individual. Pearson correlations of mean-centered methylation between paired samples ranged from r = 0.66 to r = 0.87. No individual site significantly differed between buffy coat and whole cord blood when adjusting for multiple comparisons (five sites had unadjusted Pcoat and whole cord blood are much lower than inter-individual variation, demonstrating that both sample preparation types can be analytically combined and compared.

  3. Maternal Methyl-Group Donor Intake and Global DNA (HydroxyMethylation before and during Pregnancy

    Directory of Open Access Journals (Sweden)

    Sara Pauwels

    2016-08-01

    Full Text Available It is still unclear to which extent methyl-group intake during pregnancy can affect maternal global DNA (hydroxylmethylation. Pregnancy methylation profiling and its link with methyl-group intake in a healthy population could enhance our understanding of the development of pregnancy related disorders. One hundred forty-eight women were enrolled in the MANOE (MAternal Nutrition and Offspring’s Epigenome study. Thiry-four women were enrolled before pregnancy and 116 during the first trimester of pregnancy. Global DNA (hydroxymethylation in blood using LC-MS/MS and dietary methyl-group intake (methionine, folate, betaine, and choline using a food-frequency questionnaire were estimated pre-pregnancy, during each trimester, and at delivery. Global DNA (hydroxymethylation levels were highest pre-pregnancy and at weeks 18–22 of pregnancy. We observed a positive relation between folic acid and global DNA methylation (p = 0.04 and hydroxymethylation (p = 0.04. A high intake of methionine pre-pregnancy and in the first trimester showed lower (hydroxymethylation percentage in weeks 11–13 and weeks 18–22, respectively. Choline and betaine intake in the first weeks was negatively associated with hydroxymethylation. Women with a high intake of these three methyl groups in the second and third trimester showed higher hyrdoxymethylation/methylation levels in the third trimester. To conclude, a time trend in DNA (hydroxymethylation was found and women with higher methyl-group intake showed higher methylation in the third trimester, and not in earlier phases of pregnancy.

  4. Experimental and chemical kinetic modeling study of small methyl esters oxidation: Methyl (E)-2-butenoate and methyl butanoate

    Energy Technology Data Exchange (ETDEWEB)

    Gail, S.; Sarathy, S.M.; Thomson, M.J. [Department of Mechanical and Industrial Engineering, University of Toronto, Toronto, ON M5S 3G8 (Canada); Dievart, P.; Dagaut, P. [CNRS, 1C, Ave de la Recherche Scientifique, 45071 Orleans Cedex 2 (France)

    2008-12-15

    This study examines the effect of unsaturation on the combustion of fatty acid methyl esters (FAME). New experimental results were obtained for the oxidation of methyl (E)-2-butenoate (MC, unsaturated C{sub 4} FAME) and methyl butanoate (MB, saturated C{sub 4} FAME) in a jet-stirred reactor (JSR) at atmospheric pressure under dilute conditions over the temperature range 850-1400 K, and two equivalence ratios ({phi}=0.375,0.75) with a residence time of 0.07 s. The results consist of concentration profiles of the reactants, stable intermediates, and final products, measured by probe sampling followed by on-line and off-line gas chromatography analyses. The oxidation of MC and MB in the JSR and under counterflow diffusion flame conditions was modeled using a new detailed chemical kinetic reaction mechanism (301 species and 1516 reactions) derived from previous schemes proposed in the literature. The laminar counterflow flame and JSR (for {phi}=1.13) experimental results used were from a previous study on the comparison of the combustion of both compounds. Sensitivity analyses and reaction path analyses, based on rates of reaction, were used to interpret the results. The data and the model show that MC has reaction pathways analogous to that of MB under the present conditions. The model of MC oxidation provides a better understanding of the effect of the ester function on combustion, and the effect of unsaturation on the combustion of fatty acid methyl ester compounds typically found in biodiesel. (author)

  5. Methyl methacrylate oligomerically-modified clay and its poly(methyl methacrylate) nanocomposites

    International Nuclear Information System (INIS)

    Zheng Xiaoxia; Jiang, David D.; Wilkie, Charles A.

    2005-01-01

    A methyl methacrylate oligomerically-modified clay was used to prepare poly(methyl methacrylate) clay nanocomposites by melt blending and the effect of the clay loading level on the modified clay and corresponding nanocomposite was studied. These nanocomposites were characterized by X-ray diffraction, transmission electron microscopy, thermogravimetric analysis and cone calorimetry. The results show a mixed intercalated/delaminated morphology with good nanodispersion. The compatibility between the methylacrylate-subsituted clay and poly(methyl methacrylate) (PMMA) are greatly improved compared to other oligomerically-modified clays

  6. Experimental Characterization and Modelization of Ion Exchange Kinetics for a Carboxylic Resin in Infinite Solution Volume Conditions. Application to Monovalent-Trivalent Cations Exchange

    Energy Technology Data Exchange (ETDEWEB)

    Picart, S.; Mokhtari, H.; Jobelin, I. [CEA Marcoule, Nucl Energy Div, RadioChem and Proc Dept, Actinides Chem and Convers Lab, F-30207 Bagnols Sur Ceze (France); Ramiere, I. [Fuel Simulat Lab, Fuel Study Dept, F-13108 St Paul Les Durance (France)

    2010-07-01

    This study is devoted to the characterization of ion exchange inside a microsphere of carboxylic resin. It aims at describing the kinetics of this exchange reaction which is known to be controlled by interdiffusion in the particle. The fractional attainment of equilibrium function of time depends on the concentration of the cations in the resin which can be modelled by the Nernst-Planck equation. A powerful approach for the numerical resolution of this equation is introduced in this paper. This modeling is based on the work of Helfferich but involves an implicit numerical scheme which reduces the computational cost. Knowing the diffusion coefficients of the cations in the resin and the radius of the spherical exchanger, the kinetics can be hence completely determined. When those diffusion parameters are missing, they can be deduced by fitting experimental data of fractional attainment of equilibrium. An efficient optimization tool coupled with the implicit resolution has been developed for this purpose. A monovalent/trivalent cation exchange had been experimentally characterized for a carboxylic resin. Diffusion coefficients and concentration profiles in the resin were then deduced through this new model. (authors)

  7. Managing the Planned Cessation of a Global Supply Market: Lessons Learned From the Global Cessation of the Trivalent Oral Poliovirus Vaccine Market.

    Science.gov (United States)

    Rubin, Jennifer; Ottosen, Ann; Ghazieh, Andisheh; Fournier-Caruana, Jacqueline; Ntow, Abraham Kofi; Gonzalez, Alejandro Ramirez

    2017-07-01

    The Polio Eradication and Endgame Strategic Plan 2013-2018 calls for the phased withdrawal of OPV, beginning with the globally synchronized cessation of tOPV by mid 2016. From a global vaccine supply management perspective, the strategy provided two key challenges; (1) the planned cessation of a high volume vaccine market; and (2) the uncertainty of demand leading and timeline as total vaccine requirements were contingent on epidemiology. The withdrawal of trivalent OPV provided a number of useful lessons that could be applied for the final OPV cessation. If carefully planned for and based on a close collaboration between programme partners and manufacturers, the cessation of a supply market can be undertaken with a successful outcome for both parties. As financial risks to manufacturers increase even further with OPV cessation, early engagement from the cessation planning phase and consideration of production lead times will be critical to ensure sufficient supply throughout to achieve programmatic objectives. As the GPEI will need to rely on residual stocks including with manufacturers through to the last campaign to achieve its objectives, the GPEI should consider to decide on and communicate a suitable mechanism for co-sharing of financial risks or other financial arrangement for the outer years. © The Author 2017. Published by Oxford University Press for the Infectious Diseases Society of America.

  8. Determination of 4f energy levels for trivalent lanthanide ions in YAlO{sub 3} by X-ray photoelectron spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Shimizu, Yuhei; Ueda, Kazushige, E-mail: kueda@che.kyutech.ac.jp

    2016-09-01

    A simple method to analyze 4f energy levels of trivalent lanthanide (Ln) ions was demonstrated by conventional X-ray photoelectron spectroscopy (XPS) measurements using Ln ions doped YAlO{sub 3} sintered polycrystalline samples. Although XPS peaks derived from Ln 4f states overlapped with the host's valence band consisting of O 2p states, the difference XPS spectra between Ln doped and non-doped samples showed only the Ln 4f peaks due to the large difference of photoionization cross sections between Ln 4f and O 2p orbitals. The difference spectra showing Ln 4f states were aligned at the valence band maximum (VBM) making use of the peaks of Al 2p inner shells, and the Ln{sup 3+} 4f energy levels referred to the VBM were determined from the Ln{sup 3+} 4f peak energies. The Ln{sup 3+} 4f energy levels obtained by this simple method were in good agreement with those previously obtained by resonant ultraviolet photoelectron spectroscopy measurements using single crystal samples. - Highlights: • Lanthanide (Ln) 4f energy in YAlO{sub 3} was studied by X-ray photoelectron spectroscopy. • The method used differences in photoionization probability between Ln 4f and O 2p. • Ln 4f states were obtained by difference spectra between Ln- and non-doped samples. • Obtained 4f energy levels agreed with those reported by a sophisticated method.

  9. Randomized trial to compare the safety and immunogenicity of CSL Limited's 2009 trivalent inactivated influenza vaccine to an established vaccine in United States children.

    Science.gov (United States)

    Brady, Rebecca C; Hu, Wilson; Houchin, Vonda G; Eder, Frank S; Jackson, Kenneth C; Hartel, Gunter F; Sawlwin, Daphne C; Albano, Frank R; Greenberg, Michael

    2014-12-12

    A trivalent inactivated influenza vaccine (CSL's TIV, CSL Limited) was licensed under USA accelerated approval regulations for use in persons≥18 years. We performed a randomized, observer-blind study to assess the safety and immunogenicity of CSL's TIV versus an established US-licensed vaccine in a population≥6 months to vaccination history determined the dosing regimen (one or two vaccinations). Subjects received CSL's TIV (n=739) or the established vaccine (n=735) in the autumn of 2009. Serum hemagglutination-inhibition titers were determined pre-vaccination and 30 days after the last vaccination. No febrile seizures or other vaccine-related SAEs were reported. After the first vaccination for Cohorts A and B, respectively, the relative risks of fever were 2.73 and 2.32 times higher for CSL's TIV compared to the established vaccine. Irritability and loss of appetite (for Cohort A) and malaise (for Cohort B) were also significantly higher for CSL's TIV compared to the established vaccine. Post-vaccination geometric mean titers (GMTs) for CSL's TIV versus the established vaccine were 385.49 vs. 382.45 for H1N1; 669.13 vs. 705.61 for H3N2; and 100.65 vs. 93.72 for B. CSL's TIV demonstrated immunological non-inferiority to the established vaccine in all cohorts. Copyright © 2014 Elsevier Ltd. All rights reserved.

  10. Hydrothermal synthesis and crystal structure of a europium(III) coordination polymer with 5-sulfoisophthalate trivalent anions and free 4, 4'-bipyridine molecules

    International Nuclear Information System (INIS)

    Lin Humao; Qing Caixiao; Qian Miao; Ping Xiaohong

    2005-01-01

    A novel europium(III) coordination polymer [Eu(Sip)(H 2 O) 5 ] n · nH 2 O · 1.5 n(Bipy) (I) (Sip is 5-sulfoisophthalate trivalent anion and Bipy is 4,4'-bipyridine) is hydrothermally synthesized and determined by the single crystal X-ray diffraction method. Polymer I crystallizes in the monoclinic system, space group C2/c with a = 30.7515(6), b = 10.9577(2), c = 17.5545(4) A, β = 112.040(1) deg, Z = 4. In I, each Eu 3+ ion is coordinated by four oxygen atoms from two carboxylate groups of two different Sip anions and five oxygen atoms from five coordinated water molecules to complete a deformed mono-cap square antiprism. Moreover, each Sip anion acts as a tetradentate ligand to connect two adjacent Eu 3+ ions through its two chelating carboxylate groups, resulting in one-dimensional linear chains. In addition, fifteen different kinds of hydrogen-bonding interactions link the chains, lattice water molecules, and free Bipy molecules to engender a complicated hydrogen-bonding network [ru

  11. Experimental Characterization and Modelization of Ion Exchange Kinetics for a Carboxylic Resin in Infinite Solution Volume Conditions. Application to Monovalent-Trivalent Cations Exchange

    International Nuclear Information System (INIS)

    Picart, S.; Mokhtari, H.; Jobelin, I.; Ramiere, I.

    2010-01-01

    This study is devoted to the characterization of ion exchange inside a microsphere of carboxylic resin. It aims at describing the kinetics of this exchange reaction which is known to be controlled by interdiffusion in the particle. The fractional attainment of equilibrium function of time depends on the concentration of the cations in the resin which can be modelled by the Nernst-Planck equation. A powerful approach for the numerical resolution of this equation is introduced in this paper. This modeling is based on the work of Helfferich but involves an implicit numerical scheme which reduces the computational cost. Knowing the diffusion coefficients of the cations in the resin and the radius of the spherical exchanger, the kinetics can be hence completely determined. When those diffusion parameters are missing, they can be deduced by fitting experimental data of fractional attainment of equilibrium. An efficient optimization tool coupled with the implicit resolution has been developed for this purpose. A monovalent/trivalent cation exchange had been experimentally characterized for a carboxylic resin. Diffusion coefficients and concentration profiles in the resin were then deduced through this new model. (authors)

  12. Synthesis of zirconia sol stabilized by trivalent cations (yttrium and neodymium or americium): a precursor for Am-bearing cubic stabilized zirconia.

    Science.gov (United States)

    Lemonnier, Stephane; Grandjean, Stephane; Robisson, Anne-Charlotte; Jolivet, Jean-Pierre

    2010-03-07

    Recent concepts for nuclear fuel and targets for transmuting long-lived radionuclides (minor actinides) and for the development of innovative Gen-IV nuclear fuel cycles imply fabricating host phases for actinide or mixed actinide compounds. Cubic stabilized zirconia (Zr, Y, Am)O(2-x) is one of the mixed phases tested in transmutation experiments. Wet chemical routes as an alternative to the powder metallurgy are being investigated to obtain the required phases while minimizing the handling of contaminating radioactive powder. Hydrolysis of zirconium, neodymium (a typical surrogate for americium) and yttrium in aqueous media in the presence of acetylacetone was firstly investigated. Progressive hydrolysis of zirconium acetylacetonate and sorption of trivalent cations and acacH on the zirconia particles led to a stable dispersion of nanoparticles (5-7 nm) in the 6-7 pH range. This sol gels with time or with temperature. The application to americium-containing solutions was then successfully tested: a stable sol was synthesized, characterized and used to prepare cubic stabilized zirconia (Zr, Y, Am)O(2-x).

  13. Origin of methyl torsional potential barrier – An overview

    Indian Academy of Sciences (India)

    Unknown

    This paper presents the evolution of views on methyl internal rotation ... recognized in the early years of quantum theory.1 Since then, detailed experimental and ..... C−C bond in the methyl conjugated molecules is an important factor for barrier.

  14. Allele specific expression and methylation in the bumblebee, Bombus terrestris

    Directory of Open Access Journals (Sweden)

    Zoë Lonsdale

    2017-09-01

    Full Text Available The social hymenoptera are emerging as models for epigenetics. DNA methylation, the addition of a methyl group, is a common epigenetic marker. In mammals and flowering plants methylation affects allele specific expression. There is contradictory evidence for the role of methylation on allele specific expression in social insects. The aim of this paper is to investigate allele specific expression and monoallelic methylation in the bumblebee, Bombus terrestris. We found nineteen genes that were both monoallelically methylated and monoallelically expressed in a single bee. Fourteen of these genes express the hypermethylated allele, while the other five express the hypomethylated allele. We also searched for allele specific expression in twenty-nine published RNA-seq libraries. We found 555 loci with allele-specific expression. We discuss our results with reference to the functional role of methylation in gene expression in insects and in the as yet unquantified role of genetic cis effects in insect allele specific methylation and expression.

  15. RESEARCH ARTICLE Changes of Host DNA Methylation in ...

    Indian Academy of Sciences (India)

    Navya

    2016-11-17

    Nov 17, 2016 ... *These authors contributed equally to this work. 1To whom .... Ethics statement ... three times with 700 ml of IP buffer. Methylated ... as crucial genes affected by Salmonella infection and termed these differentially methylated.

  16. Transcription factors as readers and effectors of DNA methylation.

    Science.gov (United States)

    Zhu, Heng; Wang, Guohua; Qian, Jiang

    2016-08-01

    Recent technological advances have made it possible to decode DNA methylomes at single-base-pair resolution under various physiological conditions. Many aberrant or differentially methylated sites have been discovered, but the mechanisms by which changes in DNA methylation lead to observed phenotypes, such as cancer, remain elusive. The classical view of methylation-mediated protein-DNA interactions is that only proteins with a methyl-CpG binding domain (MBD) can interact with methylated DNA. However, evidence is emerging to suggest that transcription factors lacking a MBD can also interact with methylated DNA. The identification of these proteins and the elucidation of their characteristics and the biological consequences of methylation-dependent transcription factor-DNA interactions are important stepping stones towards a mechanistic understanding of methylation-mediated biological processes, which have crucial implications for human development and disease.

  17. Solubility of ethylene in methyl propionate

    NARCIS (Netherlands)

    Shariati - Sarabi, A.; Florusse, L.J.; Peters, C.J.

    2015-01-01

    In this work, the solubility of ethylene in methyl propionate was measured within a temperature range of 283.5–464.8 K and pressures up to 10.7 MPa. Experiments were carried out using the Cailletet apparatus, which uses a synthetic method for the experiments. The critical points of several isopleths

  18. DNA Methylation Landscapes of Human Fetal Development

    NARCIS (Netherlands)

    Slieker, Roderick C.; Roost, Matthias S.; van Iperen, Liesbeth; Suchiman, H. Eka D; Tobi, Elmar W.; Carlotti, Françoise; de Koning, Eelco J P; Slagboom, P. Eline; Heijmans, Bastiaan T.; Chuva de Sousa Lopes, Susana M.

    2015-01-01

    Remodelling the methylome is a hallmark of mammalian development and cell differentiation. However, current knowledge of DNA methylation dynamics in human tissue specification and organ development largely stems from the extrapolation of studies in vitro and animal models. Here, we report on the DNA

  19. 27 CFR 21.116 - Methyl alcohol.

    Science.gov (United States)

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Methyl alcohol. 21.116 Section 21.116 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT OF THE TREASURY LIQUORS FORMULAS FOR DENATURED ALCOHOL AND RUM Specifications for Denaturants § 21...

  20. Methyl 3,4-bis(cyclopropylmethoxybenzoate

    Directory of Open Access Journals (Sweden)

    Xian-Chao Cheng

    2011-05-01

    Full Text Available The title compound, C16H20O4, was obtained unintentionally as the byproduct of an attempted synthesis of methyl 3-(cyclopropylmethoxy-4-hydroxybenzoate. In the crystal, the molecules are linked by intermolecular C—H...O interactions.

  1. Genome-Wide Methylation Profiling of Schizophrenia

    Directory of Open Access Journals (Sweden)

    Rukova B.

    2014-12-01

    Full Text Available Schizophrenia is one of the major psychiatric disorders. It is a disorder of complex inheritance, involving both heritable and environmental factors. DNA methylation is an inheritable epigenetic modification that stably alters gene expression. We reasoned that genetic modifications that are a result of environmental stimuli could also make a contribution.

  2. Atmospheric fate of methyl vinyl ketone

    DEFF Research Database (Denmark)

    Praske, Eric; Crounse, John D; Bates, Kelvin H

    2015-01-01

    First generation product yields from the OH-initiated oxidation of methyl vinyl ketone (3-buten-2-one, MVK) under both low and high NO conditions are reported. In the low NO chemistry, three distinct reaction channels are identified leading to the formation of (1) OH, glycolaldehyde, and acetyl...

  3. How does methylation suppress the electron-induced decomposition of 1-methyl-nitroimidazoles?

    Science.gov (United States)

    Kossoski, F.; Varella, M. T. do N.

    2017-10-01

    The efficient decomposition of nitroimidazoles (NIs) by low energy electrons is believed to underlie their radiosensitizing properties. Recent dissociative electron attachment (DEA) measurements showed that methylation at the N1 site unexpectedly suppresses the electron-induced reactions in 4(5)-NI. We report theoretical results that provide a clear interpretation of that astounding finding. Around 1.5 eV, DEA reactions into several fragments are initiated by a π* resonance, not considered in previous studies. The autoionization lifetime of this anion state, which limits the predissociation dynamics, is considerably shorter in the methylated species, thereby suppressing the DEA signals. On the other hand, the lifetime of the π* resonance located around 3 eV is less affected by methylation, which explains why DEA is still observed at these energies. Our results demonstrate how even a simple methylation can significantly modify the probabilities for DEA reactions, which may be significant for NI-based cancer therapy.

  4. SINE transcription by RNA polymerase III is suppressed by histone methylation but not by DNA methylation

    Science.gov (United States)

    Varshney, Dhaval; Vavrova-Anderson, Jana; Oler, Andrew J.; Cowling, Victoria H.; Cairns, Bradley R.; White, Robert J.

    2015-01-01

    Short interspersed nuclear elements (SINEs), such as Alu, spread by retrotransposition, which requires their transcripts to be copied into DNA and then inserted into new chromosomal sites. This can lead to genetic damage through insertional mutagenesis and chromosomal rearrangements between non-allelic SINEs at distinct loci. SINE DNA is heavily methylated and this was thought to suppress its accessibility and transcription, thereby protecting against retrotransposition. Here we provide several lines of evidence that methylated SINE DNA is occupied by RNA polymerase III, including the use of high-throughput bisulphite sequencing of ChIP DNA. We find that loss of DNA methylation has little effect on accessibility of SINEs to transcription machinery or their expression in vivo. In contrast, a histone methyltransferase inhibitor selectively promotes SINE expression and occupancy by RNA polymerase III. The data suggest that methylation of histones rather than DNA plays a dominant role in suppressing SINE transcription. PMID:25798578

  5. Microwave-assisted pyrolysis of methyl ricinoleate for continuous production of undecylenic acid methyl ester (UAME).

    Science.gov (United States)

    Nie, Yong; Duan, Ying; Gong, Ruchao; Yu, Shangzhi; Lu, Meizhen; Yu, Fengwen; Ji, Jianbing

    2015-06-01

    Undecylenic acid methyl ester (UAME) was continuously produced from methyl ricinoleate using a microwave-assisted pyrolysis system with atomization feeding. The UAME yield of 77 wt.% was obtained at 500°C using SiC as the microwave absorbent and heating medium. The methyl ricinoleate conversion and UAME yield from microwave-assisted pyrolysis process were higher than those from conventional pyrolysis. The effect of temperature on the pyrolysis process was also investigated. The methyl ricinoleate conversion increased but the cracking liquid yield decreased when the temperature increased from 460°C to 560°C. The maximum UAME yield was obtained at the temperature of 500°C. Copyright © 2015 Elsevier Ltd. All rights reserved.

  6. Mobility and molecular ions of dimethyl methyl phosphonate, methyl salicylate and acetone

    Science.gov (United States)

    Nowak, D. M.

    1983-06-01

    The mobilities of positive and negative reactant ions are reported for (H2O)nH(+); (H2O)2O2 and (H2O)2CO3(-) ion clusters. The formation of positive DMMP monomer and dimer is reported, and equilbria molecular reactions are reported. Acetone is reported as forming a dimer at 81 ppb with a reduced mobility (K sub o) of 1.82, Methyl salicylate is shown to form a protonated and hydrated positive monomer. Mixtures of DMMP and methyl salicylate with acetone showed a substantial change in DMMP ion clustering and little or no change in the methyl salicylate mobility spectra. Negative ions were not observed for DMMP, methyl salicylate, acetone and the mixtures under the conditions reported.

  7. Allele-Specific DNA Methylation Detection by Pyrosequencing®

    DEFF Research Database (Denmark)

    Kristensen, Lasse Sommer; Johansen, Jens Vilstrup; Grønbæk, Kirsten

    2015-01-01

    DNA methylation is an epigenetic modification that plays important roles in healthy as well as diseased cells, by influencing the transcription of genes. In spite the fact that human somatic cells are diploid, most of the currently available methods for the study of DNA methylation do not provide......-effective protocol for allele-specific DNA methylation detection based on Pyrosequencing(®) of methylation-specific PCR (MSP) products including a single nucleotide polymorphism (SNP) within the amplicon....

  8. DNA Methylation as a Biomarker for Preeclampsia

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, Cindy M.; Ralph, Jody L.; Wright, Michelle L.; Linggi, Bryan E.; Ohm, Joyce E.

    2014-10-01

    Background: Preeclampsia contributes significantly to pregnancy-associated morbidity and mortality as well as future risk of cardiovascular disease in mother and offspring, and preeclampsia in offspring. The lack of reliable methods for early detection limits the opportunities for prevention, diagnosis, and timely treatment. Purpose: The purpose of this study was to explore distinct DNA methylation patterns associated with preeclampsia in both maternal cells and fetal-derived tissue that represent potential biomarkers to predict future preeclampsia and inheritance in children. Method: A convenience sample of nulliparous women (N = 55) in the first trimester of pregnancy was recruited for this prospective study. Genome-wide DNA methylation was quantified in first-trimester maternal peripheral white blood cells and placental chorionic tissue from normotensive women and those with preeclampsia (n = 6/group). Results: Late-onset preeclampsia developed in 12.7% of women. Significant differences in DNA methylation were identified in 207 individual linked cytosine and guanine (CpG) sites in maternal white blood cells collected in the first trimester (132 sites with gain and 75 sites with loss of methylation), which were common to approximately 75% of the differentially methylated CpG sites identified in chorionic tissue of fetal origin. Conclusion: This study is the first to identify maternal epigenetic targets and common targets in fetal-derived tissue that represent putative biomarkers for early detection and heritable risk of preeclampsia. Findings may pave the way for diagnosis of preeclampsia prior to its clinical presentation and acute damaging effects, and the potential for prevention of the detrimental long-term sequelae.

  9. Usability of human Infinium MethylationEPIC BeadChip for mouse DNA methylation studies.

    Science.gov (United States)

    Needhamsen, Maria; Ewing, Ewoud; Lund, Harald; Gomez-Cabrero, David; Harris, Robert Adam; Kular, Lara; Jagodic, Maja

    2017-11-15

    The advent of array-based genome-wide DNA methylation methods has enabled quantitative measurement of single CpG methylation status at relatively low cost and sample input. Whereas the use of Infinium Human Methylation BeadChips has shown great utility in clinical studies, no equivalent tool is available for rodent animal samples. We examined the feasibility of using the new Infinium MethylationEPIC BeadChip for studying DNA methylation in mouse. In silico, we identified 19,420 EPIC probes (referred as mEPIC probes), which align with a unique best alignment score to the bisulfite converted reference mouse genome mm10. Further annotation revealed that 85% of mEPIC probes overlapped with mm10.refSeq genes at different genomic features including promoters (TSS1500 and TSS200), 1st exons, 5'UTRs, 3'UTRs, CpG islands, shores, shelves, open seas and FANTOM5 enhancers. Hybridization of mouse samples to Infinium Human MethylationEPIC BeadChips showed successful measurement of mEPIC probes and reproducibility between inter-array biological replicates. Finally, we demonstrated the utility of mEPIC probes for data exploration such as hierarchical clustering. Given the absence of cost and labor convenient genome-wide technologies in the murine system, our findings show that the Infinium MethylationEPIC BeadChip platform is suitable for investigation of the mouse methylome. Furthermore, we provide the "mEPICmanifest" with genomic features, available to users of Infinium Human MethylationEPIC arrays for mouse samples.

  10. Kinetic Isotope Effects in the Reduction of Methyl Iodide

    DEFF Research Database (Denmark)

    Holm, Torkil

    1999-01-01

    a Grignard reagent to methyl iodide, and for reduction of methyl iodide with tributyltin hydride or with gaseous hydrogen iodide. Very small KIE's were found for electron transfer to methyl iodide from magnesium in ether or from sodium in ammonia. The reason may be that these reactions are transport...

  11. Clinical Utility of promoter methylation of the tumor suppressor ...

    African Journals Online (AJOL)

    Aim: Aim is to examine the potential usefulness of blood based methylation specific polymerase chain reaction (MSP) of methylated DKK3 and RASSF1A genes in early detection of breast cancer. Method: Methylation status of DKK3 and RASSF1 was investigated in forty breast cancer patients, twenty fibroadenoma patients ...

  12. Synthesis of 14C-labelled α-methyl tyrosine

    International Nuclear Information System (INIS)

    Rajagopal, S.; Venkatachalam, T.K.; Conway, T.; Diksic, M.

    1992-01-01

    A new route for the preparation of radioactively labelled α-methyl L-tyrosine is described. The labelling at the α position has been successfully achieved with 14 C-, 11 C- (very preliminary, unpublished), and 3 H-labelled methyl iodide. A detailed report on 14 C-labelling at the α position and the hydrolysis of 4-methoxy α-methyl phenylalanine is presented. The alkylation proceeds via the methylation of the carbanion of N-benzylidene 4-methoxy phenylalanine methyl ester 2. Hydrolysis of 4-O methyl tyrosine to tyrosine by HBr and HI were analysed and used in the optimization of the hydrolysis conditions of 4. Enantiomeric purity of the isolated L-isomer has been found to be 99% as judged by HPLC. Pseudo first-order rate constant for the hydrolysis of 14 C-labelled α-methyl 4-methoxy phenyl alanine methyl ester was determined. Preliminary findings of the 3 H- and 11 C-radiolabelled α-methyl tyrosine (methyl labelled) are also mentioned. For the first time it was shown that α-methyl D,L-tyrosine can be separated into enantiomerically pure α-methyl D- and L-tyrosine using a CHIRALPAK WH column. (author)

  13. Simultaneous Determination of Salicylic Acid, Jasmonic Acid, Methyl Salicylate, and Methyl Jasmonate from Ulmus pumila Leaves by GC-MS

    Directory of Open Access Journals (Sweden)

    Zhi-hong Huang

    2015-01-01

    Full Text Available Salicylic acid, jasmonic acid, methyl salicylate, and methyl jasmonate are important phytohormones and defensive signaling compounds, so it is of great importance to determine their levels rapidly and accurately. The study uses Ulmus pumila leaves infected by Tetraneura akinire Sasaki at different stages as materials; after extraction with 80% methanol and ethyl acetate and purification with primary secondary amine (PSA and graphitized carbon blacks (GCB, the contents of signal compounds salicylic acid, jasmonic acid, methyl salicylate, and methyl jasmonate were determined by GC-MS. The results showed that the level of salicylic acid, jasmonic acid, methyl salicylate, and methyl jasmonate increased remarkably in U. pumila once infected by T. akinire Sasaki, but the maximums of these four compounds occurred at different times. Salicylic acid level reached the highest at the early stage, and jasmonic acid level went to the maximum in the middle stage; by contrast, change of content of methyl salicylate and methyl jasmonate was the quite opposite.

  14. Simultaneous Determination of Salicylic Acid, Jasmonic Acid, Methyl Salicylate, and Methyl Jasmonate from Ulmus pumila Leaves by GC-MS.

    Science.gov (United States)

    Huang, Zhi-Hong; Wang, Zhi-Li; Shi, Bao-Lin; Wei, Dong; Chen, Jian-Xin; Wang, Su-Li; Gao, Bao-Jia

    2015-01-01

    Salicylic acid, jasmonic acid, methyl salicylate, and methyl jasmonate are important phytohormones and defensive signaling compounds, so it is of great importance to determine their levels rapidly and accurately. The study uses Ulmus pumila leaves infected by Tetraneura akinire Sasaki at different stages as materials; after extraction with 80% methanol and ethyl acetate and purification with primary secondary amine (PSA) and graphitized carbon blacks (GCB), the contents of signal compounds salicylic acid, jasmonic acid, methyl salicylate, and methyl jasmonate were determined by GC-MS. The results showed that the level of salicylic acid, jasmonic acid, methyl salicylate, and methyl jasmonate increased remarkably in U. pumila once infected by T. akinire Sasaki, but the maximums of these four compounds occurred at different times. Salicylic acid level reached the highest at the early stage, and jasmonic acid level went to the maximum in the middle stage; by contrast, change of content of methyl salicylate and methyl jasmonate was the quite opposite.

  15. Synthesis of [methyl-14C]crotonobetaine from DL-[methyl-14C]carnitine

    International Nuclear Information System (INIS)

    Loester, H.; Seim, H.

    1996-01-01

    The causes of carnitine deficiency syndromes are not completely understood, but decomposition of L-carnitine in vivo is likely to be involved. Carnitine is metabolized to γ-butyrobetaine, and crotonobetaine is probably an intermediate in this pathway. To validate experimentally the precursor-product relationship between the three physiologically occuring γ-betaines - L-carnitine, crotonobetaine, γ-butyrobetaine - labelling with stable or radioactive isotopes became necessary. Methyl-labelled carnitine isomers (L(-)-, D(+)- or DL-) or γ-butyrobetaine can be easily synthesized by methylation of 4-amino-3-hydroxybutyric acid isomers or 4-aminobutyric acid, respectively. Because of problems with the 4-aminocrotonic acid, we synthesized labelled crotonbetaine from labelled carnitine. Thus, DL-[methyl- 14 C]carnitine was dehydrated by reaction with concentrated sulfuric acid. After removal of the latter the products were separated and purified by ion exchange chromatography on DOWEX 50 WX8 (200 - 400 mesh) and gradient elution with hydrochloric acid. In addition to the labelled main product [methyl- 14 C]crotonobetaine (yield about 50 %), [methyl- 14 C]glycine betaine and [methyl- 14 C]acetonyl-trimethylammonium (ATMA) were formed. The end products were identified by combined thin layer chromatography/autoradiography and quantified by liquid scintillation counting. (Author)

  16. Genome-wide methylation analysis identified sexually dimorphic methylated regions in hybrid tilapia

    Science.gov (United States)

    Wan, Zi Yi; Xia, Jun Hong; Lin, Grace; Wang, Le; Lin, Valerie C. L.; Yue, Gen Hua

    2016-01-01

    Sexual dimorphism is an interesting biological phenomenon. Previous studies showed that DNA methylation might play a role in sexual dimorphism. However, the overall picture of the genome-wide methylation landscape in sexually dimorphic species remains unclear. We analyzed the DNA methylation landscape and transcriptome in hybrid tilapia (Oreochromis spp.) using whole genome bisulfite sequencing (WGBS) and RNA-sequencing (RNA-seq). We found 4,757 sexually dimorphic differentially methylated regions (DMRs), with significant clusters of DMRs located on chromosomal regions associated with sex determination. CpG methylation in promoter regions was negatively correlated with the gene expression level. MAPK/ERK pathway was upregulated in male tilapia. We also inferred active cis-regulatory regions (ACRs) in skeletal muscle tissues from WGBS datasets, revealing sexually dimorphic cis-regulatory regions. These results suggest that DNA methylation contribute to sex-specific phenotypes and serve as resources for further investigation to analyze the functions of these regions and their contributions towards sexual dimorphisms. PMID:27782217

  17. [Specific features of 2-methyl hydroxybenzene and 3-methyl hydroxybenzene distribution in the organism of warm-blooded animals].

    Science.gov (United States)

    Shormanov, B K; Grishenko, V K; Astashkina, A P; Elizarova, M K

    2013-01-01

    The present work was designed to study the specific features of 2-methyl hydroxybezene and 3-methyl hydroxybenzene distribution after intragastric administration of these toxicants to warm-blooded animals (rats). They were detected in the unmetabolized form in the internal organs and blood of the animals. The levels of 2-methyl hydroxybezene were especially high in the stomach and blood whereas the maximum content of 3-methyl hydroxybenzene was found in brain, blood, small intestines of the poisoned rats.

  18. Evaluation of Methyl-Binding Domain Based Enrichment Approaches Revisited.

    Directory of Open Access Journals (Sweden)

    Karolina A Aberg

    Full Text Available Methyl-binding domain (MBD enrichment followed by deep sequencing (MBD-seq, is a robust and cost efficient approach for methylome-wide association studies (MWAS. MBD-seq has been demonstrated to be capable of identifying differentially methylated regions, detecting previously reported robust associations and producing findings that replicate with other technologies such as targeted pyrosequencing of bisulfite converted DNA. There are several kits commercially available that can be used for MBD enrichment. Our previous work has involved MethylMiner (Life Technologies, Foster City, CA, USA that we chose after careful investigation of its properties. However, in a recent evaluation of five commercially available MBD-enrichment kits the performance of the MethylMiner was deemed poor. Given our positive experience with MethylMiner, we were surprised by this report. In an attempt to reproduce these findings we here have performed a direct comparison of MethylMiner with MethylCap (Diagenode Inc, Denville, NJ, USA, the best performing kit in that study. We find that both MethylMiner and MethylCap are two well performing MBD-enrichment kits. However, MethylMiner shows somewhat better enrichment efficiency and lower levels of background "noise". In addition, for the purpose of MWAS where we want to investigate the majority of CpGs, we find MethylMiner to be superior as it allows tailoring the enrichment to the regions where most CpGs are located. Using targeted bisulfite sequencing we confirmed that sites where methylation was detected by either MethylMiner or by MethylCap indeed were methylated.

  19. MethylMeter(®): bisulfite-free quantitative and sensitive DNA methylation profiling and mutation detection in FFPE samples.

    Science.gov (United States)

    McCarthy, David; Pulverer, Walter; Weinhaeusel, Andreas; Diago, Oscar R; Hogan, Daniel J; Ostertag, Derek; Hanna, Michelle M

    2016-06-01

    Development of a sensitive method for DNA methylation profiling and associated mutation detection in clinical samples. Formalin-fixed and paraffin-embedded tumors received by clinical laboratories often contain insufficient DNA for analysis with bisulfite or methylation sensitive restriction enzymes-based methods. To increase sensitivity, methyl-CpG DNA capture and Coupled Abscription PCR Signaling detection were combined in a new assay, MethylMeter(®). Gliomas were analyzed for MGMT methylation, glioma CpG island methylator phenotype and IDH1 R132H. MethylMeter had 100% assay success rate measuring all five biomarkers in formalin-fixed and paraffin-embedded tissue. MGMT methylation results were supported by survival and mRNA expression data. MethylMeter is a sensitive and quantitative method for multitarget DNA methylation profiling and associated mutation detection. The MethylMeter-based GliomaSTRAT assay measures methylation of four targets and one mutation to simultaneously grade gliomas and predict their response to temozolomide. This information is clinically valuable in management of gliomas.

  20. Dietary and supplemental maternal methyl-group donor intake and cord blood DNA methylation.

    Science.gov (United States)

    Pauwels, Sara; Ghosh, Manosij; Duca, Radu Corneliu; Bekaert, Bram; Freson, Kathleen; Huybrechts, Inge; A S Langie, Sabine; Koppen, Gudrun; Devlieger, Roland; Godderis, Lode

    2017-01-02

    Maternal nutrition is critically involved in the development and health of the fetus. We evaluated maternal methyl-group donor intake through diet (methionine, betaine, choline, folate) and supplementation (folic acid) before and during pregnancy in relation to global DNA methylation and hydroxymethylation and gene specific (IGF2 DMR, DNMT1, LEP, RXRA) cord blood methylation. A total of 115 mother-infant pairs were enrolled in the MAternal Nutrition and Offspring's Epigenome (MANOE) study. The intake of methyl-group donors was assessed using a food-frequency questionnaire. LC-MS/MS and pyrosequencing were used to measure global and gene specific methylation, respectively. Dietary intake of methyl-groups before and during pregnancy was associated with changes in LEP, DNMT1, and RXRA cord blood methylation. Statistically significant higher cord blood LEP methylation was observed when mothers started folic acid supplementation more than 6 months before conception compared with 3-6 months before conception (34.6 ± 6.3% vs. 30.1 ± 3.6%, P = 0.011, LEP CpG1) or no folic acid used before conception (16.2 ± 4.4% vs. 13.9 ± 3%, P = 0.036 for LEP CpG3 and 24.5 ± 3.5% vs. 22.2 ± 3.5%, P = 0.045 for LEP mean CpG). Taking folic acid supplements during the entire pregnancy resulted in statistically significantly higher cord blood RXRA methylation as compared with stopping supplementation in the second trimester (12.3 ± 1.9% vs. 11.1 ± 2%, P = 0.008 for RXRA mean CpG). To conclude, long-term folic acid use before and during pregnancy was associated with higher LEP and RXRA cord blood methylation, respectively. To date, pregnant women are advised to take a folic acid supplement of 400 µg/day from 4 weeks before until 12 weeks of pregnancy. Our results suggest significant epigenetic modifications when taking a folic acid supplement beyond the current advice.

  1. The global DNA methylation surrogate LINE-1 methylation is correlated with MGMT promoter methylation and is a better prognostic factor for glioma.

    Directory of Open Access Journals (Sweden)

    Fumiharu Ohka

    Full Text Available Gliomas are the most frequently occurring primary brain tumor in the central nervous system of adults. Glioblastoma multiformes (GBMs, WHO grade 4 have a dismal prognosis despite the use of the alkylating agent, temozolomide (TMZ, and even low grade gliomas (LGGs, WHO grade 2 eventually transform to malignant secondary GBMs. Although GBM patients benefit from promoter hypermethylation of the O(6-methylguanine-DNA methyltransferase (MGMT that is the main determinant of resistance to TMZ, recent studies suggested that MGMT promoter methylation is of prognostic as well as predictive significance for the efficacy of TMZ. Glioma-CpG island methylator phenotype (G-CIMP in the global genome was shown to be a significant predictor of improved survival in patients with GBM. Collectively, we hypothesized that MGMT promoter methylation might reflect global DNA methylation. Additionally in LGGs, the significance of MGMT promoter methylation is still undetermined. In the current study, we aimed to determine the correlation between clinical, genetic, and epigenetic profiles including LINE-1 and different cancer-related genes and the clinical outcome in newly diagnosed 57 LGG and 54 GBM patients. Here, we demonstrated that (1 IDH1/2 mutation is closely correlated with MGMT promoter methylation and 1p/19q codeletion in LGGs, (2 LINE-1 methylation levels in primary and secondary GBMs are lower than those in LGGs and normal brain tissues, (3 LINE-1 methylation is proportional to MGMT promoter methylation in gliomas, and (4 higher LINE-1 methylation is a favorable prognostic factor in primary GBMs, even compared to MGMT promoter methylation. As a global DNA methylation marker, LINE-1 may be a promising marker in gliomas.

  2. DNA methylation in sugarcane somaclonal variants assessed through methylation-sensitive amplified polymorphism.

    Science.gov (United States)

    Francischini, J H M B; Kemper, E L; Costa, J B; Manechini, J R V; Pinto, L R

    2017-05-04

    Micropropagation is an important tool for large-scale multiplication of plant superior genotypes. However, somaclonal variation is one of the drawbacks of this process. Changes in DNA methylation have been widely reported as one of the main causes of somaclonal variations in plants. In order to investigate the occurrence of changes in the methylation pattern of sugarcane somaclonal variants, the MSAP (methylation-sensitive amplified polymorphism) technique was applied to micro-propagated plantlets sampled at the third subculture phase. The mother plant, in vitro normal plantlets, and in vitro abnormal plantlets (somaclonal variants) of four sugarcane clones were screened against 16 MSAP selective primers for EcoRI/MspI and EcoRI/HpaII restriction enzymes. A total of 1005 and 1200 MSAP-derived markers with polymorphism percentages of 28.36 and 40.67 were obtained for EcoRI/HpaII and EcoRI/MspI restriction enzyme combinations, respectively. The genetic similarity between the mother plant and the somaclonal variants ranged from 0.877 to 0.911 (EcoRI/MspI) and from 0.928 to 0.955 (EcoRI/HpaII). Most of the MASPs among mother plant and micro-propagated plantlets were derived from EcoRI/MspI restriction enzymes suggesting alteration due to gain or loss of internal cytosine methylation. A higher rate of loss of methylation (hypomethylation) than gain of methylation (hypermethylation) was observed in the abnormal in vitro sugarcane plantlets. Although changes in the methylation pattern were also observed in the in vitro normal plantlets, they were lower than those observed for the in vitro abnormal plantlets. The MASP technique proved to be a promising tool to early assessment of genetic fidelity of micro-propagated sugarcane plants.

  3. A genome-wide methylation study on obesity: differential variability and differential methylation.

    Science.gov (United States)

    Xu, Xiaojing; Su, Shaoyong; Barnes, Vernon A; De Miguel, Carmen; Pollock, Jennifer; Ownby, Dennis; Shi, Hidong; Zhu, Haidong; Snieder, Harold; Wang, Xiaoling

    2013-05-01

    Besides differential methylation, DNA methylation variation has recently been proposed and demonstrated to be a potential contributing factor to cancer risk. Here we aim to examine whether differential variability in methylation is also an important feature of obesity, a typical non-malignant common complex disease. We analyzed genome-wide methylation profiles of over 470,000 CpGs in peripheral blood samples from 48 obese and 48 lean African-American youth aged 14-20 y old. A substantial number of differentially variable CpG sites (DVCs), using statistics based on variances, as well as a substantial number of differentially methylated CpG sites (DMCs), using statistics based on means, were identified. Similar to the findings in cancers, DVCs generally exhibited an outlier structure and were more variable in cases than in controls. By randomly splitting the current sample into a discovery and validation set, we observed that both the DVCs and DMCs identified from the first set could independently predict obesity status in the second set. Furthermore, both the genes harboring DMCs and the genes harboring DVCs showed significant enrichment of genes identified by genome-wide association studies on obesity and related diseases, such as hypertension, dyslipidemia, type 2 diabetes and certain types of cancers, supporting their roles in the etiology and pathogenesis of obesity. We generalized the recent finding on methylation variability in cancer research to obesity and demonstrated that differential variability is also an important feature of obesity-related methylation changes. Future studies on the epigenetics of obesity will benefit from both statistics based on means and statistics based on variances.

  4. Methylation profiling identified novel differentially methylated markers including OPCML and FLRT2 in prostate cancer.

    Science.gov (United States)

    Wu, Yu; Davison, Jerry; Qu, Xiaoyu; Morrissey, Colm; Storer, Barry; Brown, Lisha; Vessella, Robert; Nelson, Peter; Fang, Min

    2016-04-02

    To develop new methods to distinguish indolent from aggressive prostate cancers (PCa), we utilized comprehensive high-throughput array-based relative methylation (CHARM) assay to identify differentially methylated regions (DMRs) throughout the genome, including both CpG island (CGI) and non-CGI regions in PCa patients based on Gleason grade. Initially, 26 samples, including 8 each of low [Gleason score (GS) 6] and high (GS ≥7) grade PCa samples and 10 matched normal prostate tissues, were analyzed as a discovery cohort. We identified 3,567 DMRs between normal and cancer tissues, and 913 DMRs distinguishing low from high-grade cancers. Most of these DMRs were located at CGI shores. The top 5 candidate DMRs from the low vs. high Gleason comparison, including OPCML, ELAVL2, EXT1, IRX5, and FLRT2, were validated by pyrosequencing using the discovery cohort. OPCML and FLRT2 were further validated in an independent cohort consisting of 20 low-Gleason and 33 high-Gleason tissues. We then compared patients with biochemical recurrence (n=70) vs. those without (n=86) in a third cohort, and they showed no difference in methylation at these DMR loci. When GS 3+4 cases and GS 4+3 cases were compared, OPCML-DMR methylation showed a trend of lower methylation in the recurrence group (n=30) than in the no-recurrence (n=52) group. We conclude that whole-genome methylation profiling with CHARM revealed distinct patterns of differential DNA methylation between normal prostate and PCa tissues, as well as between different risk groups of PCa as defined by Gleason scores. A panel of selected DMRs may serve as novel surrogate biomarkers for Gleason score in PCa.

  5. Regulation and function of DNA methylation in plants and animals

    KAUST Repository

    He, Xinjian

    2011-02-15

    DNA methylation is an important epigenetic mark involved in diverse biological processes. In plants, DNA methylation can be established through the RNA-directed DNA methylation pathway, an RNA interference pathway for transcriptional gene silencing (TGS), which requires 24-nt small interfering RNAs. In mammals, de novo DNA methylation occurs primarily at two developmental stages: during early embryogenesis and during gametogenesis. While it is not clear whether establishment of DNA methylation patterns in mammals involves RNA interference in general, de novo DNA methylation and suppression of transposons in germ cells require 24-32-nt piwi-interacting small RNAs. DNA methylation status is dynamically regulated by DNA methylation and demethylation reactions. In plants, active DNA demethylation relies on the repressor of silencing 1 family of bifunctional DNA glycosylases, which remove the 5-methylcytosine base and then cleave the DNA backbone at the abasic site, initiating a base excision repair (BER) pathway. In animals, multiple mechanisms of active DNA demethylation have been proposed, including a deaminase- and DNA glycosylase-initiated BER pathway. New information concerning the effects of various histone modifications on the establishment and maintenance of DNA methylation has broadened our understanding of the regulation of DNA methylation. The function of DNA methylation in plants and animals is also discussed in this review. © 2011 IBCB, SIBS, CAS All rights reserved.

  6. Methyl bromide residues in fumigated cocoa beans

    International Nuclear Information System (INIS)

    Adomako, D.

    1975-01-01

    The 14 C activity in unroasted [ 14 C]-methyl bromide fumigated cocoa beans was used to study the fate and persistence of CH 3 Br in the stored beans. About 70% of the residues occurred in the shells. Unchanged CH 3 Br could not be detected, all the sorbed CH 3 Br having reacted with bean constituents apparently to form 14 C-methylated derivatives and inorganic bromide. No 14 C activity was found in the lipid fraction. Roasting decreased the bound (non-volatile) residues, with corresponding changes in the activities and amounts of free sugars, free and protein amino acids. Roasted nibs and shells showed a two-fold increase in the volatile fraction of the 14 C residue. This fraction may be related to the volatile aroma compounds formed by Maillard-type reactions. (author)

  7. Diet and Asthma: Vitamins and Methyl Donors

    Science.gov (United States)

    Han, Yueh-Ying; Blatter, Josh; Brehm, John M.; Forno, Erick; Litonjua, Augusto A; Celedón, Juan C.

    2014-01-01

    SUMMARY Dietary changes may partly explain the high burden of asthma in industrialized nations. Experimental studies have motivated a significant number of observational studies of the relation between vitamins (A, C, D, and E) or nutrients acting as methyl donors (folate, vitamin B12, and choline) and asthma. Because observational studies are susceptible to several sources of bias, well-conducted randomized controlled trials (RCTs) remain the “gold standard” to determine whether a vitamin or nutrient has an effect on asthma. Evidence from observational studies and/or relatively few RCTs most strongly justify ongoing and future RCTs of: 1) vitamin D to prevent or treat asthma, 2) choline supplementation as adjuvant treatment for asthma, and 3) vitamin E to prevent the detrimental effects of air pollution in subjects with asthma. At this time, there is insufficient evidence to recommend supplementation with any vitamin or nutrient acting as a methyl donor to prevent or treat asthma. PMID:24461761

  8. Adsorption of methyl iodide on charcoal

    International Nuclear Information System (INIS)

    Hidajat, K.; Aracil, J.; Kenney, C.N.

    1990-01-01

    The adsorption of non-radioactive methyl iodide has been measured experimentally over a range of conditions of concentration, and temperature on an activated charcoal. This is of interest since methyl iodide is formed from iodine fission products in gas cooled nuclear reactors. A mathematical model has also been developed which describes the rate of adsorption, under isothermal and linear adsorption isotherm conditions in a recycle adsorber. This model takes into account the resistance to adsorption caused by the surface adsorption, as well as the external and internal mass transfer resistances. The solution to the model for the recycle adsorber was obtained using a semidiscretisation method to reduce the partial differential equations to a system of stiff ordinary differential equations, and the resulting differential equations solved by a standard numerical technique. (author)

  9. Quantitative description and local structures of trivalent metal ions Eu(III) and Cm(III) complexed with poly-acrylic acid

    International Nuclear Information System (INIS)

    Montavon, G.; Huclier-Markai, S.; Grambow, B.; Bouby, M.; Geckeis, H.; Rabung, T.; Huclier-Markai, S.; Pashalidis, I.; Amekraz, B.; Moulin, C.

    2008-01-01

    The trivalent metal ion (M(III) = Cm, Eu)/poly-acrylic acid (PAA) system was studied in the pH range between 3 and 5.5 for a molar PAA-to-metal ratio above 1. The interaction was studied for a wide range of PAA (0.05 mg L -1 -50 g L -1 ) and metal ion concentrations (2*10 -9 - 10 -3 M). This work aimed at 3 goals (i) to determine the stoichiometry of M(III)-PAA complexes, (ii) to determine the number of complexed species and the local environment of the metal ion, and (iii) to quantify the reaction processes. Asymmetric flow-field-flow fractionation (AsFIFFF) coupled to ICP-MS evidenced that size distributions of Eu-PAA complexes and PAA were identical, suggesting that Eu bound to only one PAA chain. Time-resolved laser fluorescence spectroscopy (TRLFS) measurements performed with Eu and Cm showed a continuous shift of the spectra with increasing pH. The environment of complexed metal ions obviously changes with pH. Most probably, spectral variations arose from conformational changes within the M(Ill)-PAA complex due to pH variation. Complexation data describing the distribution of complexed and free metal ion were measured with Cm by TRLFS. They could be quantitatively described in the whole pH-range studied by considering the existence of only a single complexed species. This indicates that the slight changes in M(III) speciation with pH observed at the molecular level do not significantly affect the intrinsic binding constant. The interaction constant obtained from the modelling must be considered as a mean interaction constant. (authors)

  10. The study of electroplating trivalent CrC alloy coatings with different current densities on stainless steel 304 as bipolar plate of proton exchange membrane fuel cells

    International Nuclear Information System (INIS)

    Wang, Hsiang-Cheng; Hou, Kung-Hsu; Lu, Chen-En; Ger, Ming-Der

    2014-01-01

    In this study, the trivalent Cr–C coatings were electroplated on stainless steel 304 (SS304) substrates for an application in bipolar plates (BPPs) that was because of coating's excellent electric conductivity and corrosion resistance. The images of scanning electron microscope showed that the thickness of the coatings was between 1.4 and 11.4 μm, which increased with increase of coating current density. The surface morphology of Cr–C plated at coating current density of 10 A/dm 2 was smooth, crack- and pinhole-free, while cracks and pinholes appearing in networks were observed apparently in the deposits plated at a higher coating current density. Additionally, the C content in the coating decreased with increasing the coating current density. Moreover, the polarization curve with different coating current densities (10, 30, 50 A/dm 2 ) exhibited the coating prepared at 10 A/dm 2 and 10 min possessing the best corrosion resistance (I corr = 9.360 × 10 −8 A/cm 2 ). The contact resistance of Cr–C plated at coating current density of 10 A/dm 2 was the lowest (16.54 mΩ cm 2 at 150 N cm −2 ), which showed great potential of application. The single cell test with Cr–C coated SS304 prepared at coating current density of 10 A/dm 2 as BPPs showed the highest current density (about 791.532 mA/cm 2 ) and power density (about 270.150 mW/cm 2 ). - Highlights: • The Cr–C coatings on steel are electroplated for utilization as bipolar plate. • The electrical conductivity and corrosion resistance increase with carbon content. • The power density of Cr–C coated steel is superior to the bare steel

  11. Thermal and spectroscopic study to investigate p-aminobenzoic acid, sodium p-aminobenzoate and its compounds with some lighter trivalent lanthanides

    International Nuclear Information System (INIS)

    Teixeira, J.A.; Nunes, W.D.G.; Colman, T.A.D.; Nascimento, A.L.C.S do; Caires, F.J.; Campos, F.X.; Gálico, D.A.; Ionashiro, M.

    2016-01-01

    Highlights: • The p-aminobenzoic acid melts followed partial evaporation. • The stoichiometry of compounds was established by TG, EA and complexometry. • The TG–DTA curves provided previously unreported information about thermal behavior. - Abstract: The characterization, thermal stability and thermal decomposition of some lighter trivalent lanthanide p-aminobenzoates, Ln(C 7 H 6 NO 2 ) 3 ·H 2 O (Ln = La, Ce, Pr, Nd, Sm), as well as the thermal behavior and spectroscopic study of p-aminobenzoic acid C 7 H 7 NO 2 and its sodium salt were investigated. The following methods were utilized: simultaneous thermogravimetry and differential thermal analysis (TG–DTA) in dynamic dry air and nitrogen atmospheres; differential scanning calorimetry (DSC); middle (MIR) and near (NIR) infrared region spectroscopy; evolved gas analysis (EGA); elemental analysis; complexometry; X-ray diffraction (XRD); and diffuse reflectance spectroscopy (DR) in the ultraviolet and visible regions. All the compounds were obtained monohydrated and the thermal decomposition occurred in two, three or four steps in an air atmosphere, and three or four steps in N 2 atmosphere. In both atmospheres (air and N 2 ) the final residues were CeO 2 , Pr 6 O 11 , Ln 2 O 3 (Ln = La, Nd, Sm). The results also provided information concerning the coordination mode and thermal behavior, as well as the identification of the gaseous products which evolved during the thermal decomposition of these compounds. The DR and NIR spectra provided information about the ligand absorption bands and the f–f transitions of the Nd 3+ , Pr 3+ and Sm 3+ ions.

  12. Immunogenicity and safety of high-dose trivalent inactivated influenza vaccine compared to standard-dose vaccine in children and young adults with cancer or HIV infection.

    Science.gov (United States)

    Hakim, Hana; Allison, Kim J; Van de Velde, Lee-Ann; Tang, Li; Sun, Yilun; Flynn, Patricia M; McCullers, Jonathan A

    2016-06-08

    Approaches to improve the immune response of immunocompromised patients to influenza vaccination are needed. Children and young adults (3-21 years) with cancer or HIV infection were randomized to receive 2 doses of high-dose (HD) trivalent influenza vaccine (TIV) or of standard-dose (SD) TIV. Hemagglutination inhibition (HAI) antibody titers were measured against H1, H3, and B antigens after each dose and 9 months later. Seroconversion was defined as ≥4-fold rise in HAI titer comparing pre- and post-vaccine sera. Seroprotection was defined as a post-vaccine HAI titer ≥1:40. Reactogenicity events (RE) were solicited using a structured questionnaire 7 and 14 days after each dose of vaccine, and adverse events by medical record review for 21 days after each dose of vaccine. Eighty-five participants were enrolled in the study; 27 with leukemia, 17 with solid tumor (ST), and 41 with HIV. Recipients of HD TIV had significantly greater fold increase in HAI titers to B antigen in leukemia group and to H1 antigen in ST group compared to SD TIV recipients. This increase was not documented in HIV group. There were no differences in seroconversion or seroprotection between HD TIV and SD TIV in all groups. There was no difference in the percentage of solicited RE in recipients of HD TIV (54% after dose 1 and 38% after dose 2) compared to SD TIV (40% after dose 1 and 20% after dose 2, p=0.27 and 0.09 after dose 1 and 2, respectively). HD TIV was more immunogenic than SD TIV in children and young adults with leukemia or ST, but not with HIV. HD TIV was safe and well-tolerated in children and young adults with leukemia, ST, or HIV. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. Safety and tolerability of a cell culture derived trivalent subunit inactivated influenza vaccine administered to healthy children and adolescents: A Phase III, randomized, multicenter, observer-blind study.

    Science.gov (United States)

    Nolan, Terry; Chotpitayasunondh, Tawee; Capeding, Maria Rosario; Carson, Simon; Senders, Shelly David; Jaehnig, Peter; de Rooij, Richard; Chandra, Richa

    2016-01-04

    Cell culture-derived inactivated influenza vaccines (TIVc) are necessary for scale and predictability of production to meet global demand. This study compared the safety and tolerability of TIVc with an egg-derived trivalent influenza vaccine (TIVf) in 4-17 yearolds. A Phase 3 observer blind, multicenter study enrolled 2055 healthy participants randomized 2:1 to receive either TIVc or TIVf, respectively (1372 TIVc and 683 TIVf evaluable subjects). Participants received one dose each on Days 1 and 28 (4-8 year-olds not previously vaccinated [NPV]) or one dose on Day 1 (4-8 and 9-17 yearolds previously vaccinated [PV]). Solicited adverse events (AEs) occurring within 7 days after each vaccination were assessed; participants were followed up for 6 months after their last dose for safety. Most solicited and unsolicited AEs were mild to moderate with vaccine-related SAEs were reported. TIVc and TIVf were similar in percentages of participants reporting solicited reactions in 4-8 years NPV group after the 1st dose: local reactions, TIVc: 48%, TIVf: 43%; systemic reactions, TIVc: 34%, TIVf: 32%; percentages were lower following the 2nd dose in TIVc; local reactions: TIVc: 40%; TIVf: 43%; systemic reactions: TIVc: 21%; TIVf: 22%. In 4-17 years PV group, solicited reactions were lower following TIVf, local reactions: TIVc: 53%; TIVf: 43%; systemic reactions: TIVc: 37%, TIVf: 30%. Injection-site pain was the most common solicited reaction, and was similar following TIVc and TIVf in 4-8 yearolds (TIVc: 56%; TIVf: 55%), and lower following TIVf in 9-17 years group (TIVc: 52%; TIVf: 42%). Reporting of unsolicited AEs was similar for TIVc and TIVf across the two age groups. TIVc was well tolerated and had a safety and reactogenicity profile similar to that of TIVf in healthy 4-17 yearolds (NCT01857206). Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

  14. Safety and Immunogenicity of Full-Dose Trivalent Inactivated Influenza Vaccine (TIV) Compared With Half-Dose TIV Administered to Children 6 Through 35 Months of Age.

    Science.gov (United States)

    Halasa, Natasha B; Gerber, Michael A; Berry, Andrea A; Anderson, Edwin L; Winokur, Patricia; Keyserling, Harry; Eckard, Allison Ross; Hill, Heather; Wolff, Mark C; McNeal, Monica M; Edwards, Kathryn M; Bernstein, David I

    2015-09-01

    Children 6 through 35 months of age are recommended to receive half the dose of influenza vaccine compared with older children and adults. This was a 6-site, randomized 2:1, double-blind study comparing full-dose (0.5 mL) trivalent inactivated influenza vaccine (TIV) with half-dose (0.25 mL) TIV in children 6 through 35 months of age. Children previously immunized with influenza vaccine (primed cohort) received 1 dose, and those with no previous influenza immunizations (naive cohort) received 2 doses of TIV. Local and systemic adverse events were recorded. Sera were collected before immunization and 1 month after last dose of TIV. Hemagglutination inhibition antibody testing was performed. Of the 243 subjects enrolled (32 primed, 211 naive), data for 232 were available for complete analysis. No significant differences in local or systemic reactions were observed. Few significant differences in immunogenicity to the 3 vaccine antigens were noted. The immune response to H1N1 was significantly higher in the full-dose group among primed subjects. In the naive cohort, the geometric mean titer for all 3 antigens after 2 doses of TIV were significantly higher in the 12 through 35 months compared with the 6 through 11 months age group. Our study confirms the safety of full-dose TIV given to children 6 through 35 months of age. An increase in antibody responses after full- versus half-dose TIV was not observed, except for H1N1 in the primed group. Larger studies are needed to clarify the potential for improved immunogenicity with higher vaccine doses. Recommending the same dose could simplify the production, storage, and administration of influenza vaccines.

  15. The study of electroplating trivalent CrC alloy coatings with different current densities on stainless steel 304 as bipolar plate of proton exchange membrane fuel cells

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Hsiang-Cheng [Graduate School of Defense Science, Chung Cheng Institute of Technology, National Defense University, Taoyuan, Taiwan (China); Hou, Kung-Hsu, E-mail: khou@ndu.edu.tw [Department of Power Vehicle and Systems Engineering, Chung Cheng Institute of Technology, National Defense University, Taoyuan, Taiwan (China); Lu, Chen-En [Graduate School of Defense Science, Chung Cheng Institute of Technology, National Defense University, Taoyuan, Taiwan (China); Ger, Ming-Der [Department of Applied Chemistry and Materials Engineering, Chung Cheng Institute of Technology, National Defense University, Taoyuan, Taiwan (China)

    2014-11-03

    In this study, the trivalent Cr–C coatings were electroplated on stainless steel 304 (SS304) substrates for an application in bipolar plates (BPPs) that was because of coating's excellent electric conductivity and corrosion resistance. The images of scanning electron microscope showed that the thickness of the coatings was between 1.4 and 11.4 μm, which increased with increase of coating current density. The surface morphology of Cr–C plated at coating current density of 10 A/dm{sup 2} was smooth, crack- and pinhole-free, while cracks and pinholes appearing in networks were observed apparently in the deposits plated at a higher coating current density. Additionally, the C content in the coating decreased with increasing the coating current density. Moreover, the polarization curve with different coating current densities (10, 30, 50 A/dm{sup 2}) exhibited the coating prepared at 10 A/dm{sup 2} and 10 min possessing the best corrosion resistance (I{sub corr} = 9.360 × 10{sup −8} A/cm{sup 2}). The contact resistance of Cr–C plated at coating current density of 10 A/dm{sup 2} was the lowest (16.54 mΩ cm{sup 2} at 150 N cm{sup −2}), which showed great potential of application. The single cell test with Cr–C coated SS304 prepared at coating current density of 10 A/dm{sup 2} as BPPs showed the highest current density (about 791.532 mA/cm{sup 2}) and power density (about 270.150 mW/cm{sup 2}). - Highlights: • The Cr–C coatings on steel are electroplated for utilization as bipolar plate. • The electrical conductivity and corrosion resistance increase with carbon content. • The power density of Cr–C coated steel is superior to the bare steel.

  16. Thermal and spectroscopic study to investigate p-aminobenzoic acid, sodium p-aminobenzoate and its compounds with some lighter trivalent lanthanides

    Energy Technology Data Exchange (ETDEWEB)

    Teixeira, J.A.; Nunes, W.D.G.; Colman, T.A.D.; Nascimento, A.L.C.S do [Instituto de Química, UNESP—Universidade Estadual Paulista, Campus Araraquara, Departamento de Química Analítica, Araraquara 14801-970, SP (Brazil); Caires, F.J. [Faculdade de Ciências, UNESP—Universidade Estadual Paulista, Campus Bauru, Departamento de Química, Bauru 17033-260, SP (Brazil); Campos, F.X. [Instituto de Química, UNESP—Universidade Estadual Paulista, Campus Araraquara, Departamento de Química Analítica, Araraquara 14801-970, SP (Brazil); Instituto Federal de Educação, Ciência e Tecnologia de Mato Grosso, Primavera do Leste 78850-000, MT (Brazil); Gálico, D.A. [Instituto de Química, UNICAMP—Universidade Estadual de Campinas, Campinas 13083-970, SP (Brazil); Ionashiro, M., E-mail: massaoi@yahoo.com.br [Instituto de Química, UNESP—Universidade Estadual Paulista, Campus Araraquara, Departamento de Química Analítica, Araraquara 14801-970, SP (Brazil)

    2016-01-20

    Highlights: • The p-aminobenzoic acid melts followed partial evaporation. • The stoichiometry of compounds was established by TG, EA and complexometry. • The TG–DTA curves provided previously unreported information about thermal behavior. - Abstract: The characterization, thermal stability and thermal decomposition of some lighter trivalent lanthanide p-aminobenzoates, Ln(C{sub 7}H{sub 6}NO{sub 2}){sub 3}·H{sub 2}O (Ln = La, Ce, Pr, Nd, Sm), as well as the thermal behavior and spectroscopic study of p-aminobenzoic acid C{sub 7}H{sub 7}NO{sub 2} and its sodium salt were investigated. The following methods were utilized: simultaneous thermogravimetry and differential thermal analysis (TG–DTA) in dynamic dry air and nitrogen atmospheres; differential scanning calorimetry (DSC); middle (MIR) and near (NIR) infrared region spectroscopy; evolved gas analysis (EGA); elemental analysis; complexometry; X-ray diffraction (XRD); and diffuse reflectance spectroscopy (DR) in the ultraviolet and visible regions. All the compounds were obtained monohydrated and the thermal decomposition occurred in two, three or four steps in an air atmosphere, and three or four steps in N{sub 2} atmosphere. In both atmospheres (air and N{sub 2}) the final residues were CeO{sub 2}, Pr{sub 6}O{sub 11}, Ln{sub 2}O{sub 3} (Ln = La, Nd, Sm). The results also provided information concerning the coordination mode and thermal behavior, as well as the identification of the gaseous products which evolved during the thermal decomposition of these compounds. The DR and NIR spectra provided information about the ligand absorption bands and the f–f transitions of the Nd{sup 3+}, Pr{sup 3+} and Sm{sup 3+} ions.

  17. Trivalent dimethylarsenic compound induces histone H3 phosphorylation and abnormal localization of Aurora B kinase in HepG2 cells

    International Nuclear Information System (INIS)

    Suzuki, Toshihide; Miyazaki, Koichi; Kita, Kayoko; Ochi, Takafumi

    2009-01-01

    Trivalent dimethylarsinous acid [DMA(III)] has been shown to induce mitotic abnormalities, such as centrosome abnormality, multipolar spindles, multipolar division, and aneuploidy, in several cell lines. In order to elucidate the mechanisms underlying these mitotic abnormalities, we investigated DMA(III)-mediated changes in histone H3 phosphorylation and localization of Aurora B kinase, which is a key molecule in cell mitosis. DMA(III) caused the phosphorylation of histone H3 (ser10) and was distributed predominantly in mitotic cells, especially in prometaphase cells. By contrast, most of the phospho-histone H3 was found to be localized in interphase cells after treatment with inorganic arsenite [iAs(III)], suggesting the involvement of a different pathway in phosphorylation. DMA(III) activated Aurora B kinase and slightly activated ERK MAP kinase. Phosphorylation of histone H3 by DMA(III) was effectively reduced by ZM447439 (Aurora kinase inhibitor) and slightly reduced by U0126 (MEK inhibitor). By contrast, iAs(III)-dependent histone H3 phosphorylation was markedly reduced by U0126. Aurora B kinase is generally localized in the midbody during telophase and plays an important role in cytokinesis. However, in some cells treated with DMA(III), Aurora B was not localized in the midbody of telophase cells. These findings suggested that DMA(III) induced a spindle abnormality, thereby activating the spindle assembly checkpoint (SAC) through the Aurora B kinase pathway. In addition, cytokinesis was not completed because of the abnormal localization of Aurora B kinase by DMA(III), thereby resulting in the generation of multinucleated cells. These results provide insight into the mechanism of arsenic tumorigenesis.

  18. Dietary Enterococcus faecium NCIMB 10415 and Zinc Oxide Stimulate Immune Reactions to Trivalent Influenza Vaccination in Pigs but Do Not Affect Virological Response upon Challenge Infection

    Science.gov (United States)

    Wang, Zhenya; Burwinkel, Michael; Chai, Weidong; Lange, Elke; Blohm, Ulrike; Breithaupt, Angele; Hoffmann, Bernd; Twardziok, Sven; Rieger, Juliane; Janczyk, Pawel; Pieper, Robert; Osterrieder, Nikolaus

    2014-01-01

    Swine influenza viruses (SIV) regularly cause significant disease in pigs worldwide. Since there is no causative treatment of SIV, we tested if probiotic Enterococcus (E.) faecium NCIMB 10415 or zinc (Zn) oxide as feed supplements provide beneficial effects upon SIV infection in piglets. Seventy-two weaned piglets were fed three different diets containing either E. faecium or different levels of Zn (2500 ppm, Znhigh; 50 ppm, Znlow). Half of the piglets were vaccinated intramuscularly (VAC) twice with an inactivated trivalent SIV vaccine, while all piglets were then infected intranasally with H3N2 SIV. Significantly higher weekly weight gains were observed in the E. faecium group before virus infection, and piglets in Znhigh and E. faecium groups gained weight after infection while those in the control group (Znlow) lost weight. Using ELISA, we found significantly higher H3N2-specific antibody levels in the E. faecium+VAC group 2 days before and at the day of challenge infection as well as at 4 and 6 days after challenge infection. Higher hemagglutination inhibition (HI) titers were also observed in the Znhigh+VAC and E. faecium+VAC groups at 0, 1 and 4 days after infection. However, there were no significant differences in virus shedding and lung lesions between the dietary groups. Using flow cytometry analysis significantly higher activated T helper cells and cytotoxic T lymphocyte percentages in the PBMCs were detected in the Znhigh and E. faecium groups at single time points after infection compared to the Znlow control group, but no prolonged effect was found. In the BAL cells no influence of dietary supplementation on immune cell percentages could be detected. Our results suggest that feeding high doses of zinc oxide and particularly E. faecium could beneficially influence humoral immune responses after vaccination and recovery from SIV infection, but not affect virus shedding and lung pathology. PMID:24489827

  19. Luminescence quenching versus enhancement in WO3-NaPO3 glasses doped with trivalent rare earth ions and containing silver nanoparticles

    Science.gov (United States)

    Dousti, M. Reza; Poirier, Gael Y.; Amjad, Raja J.; de Camargo, Andrea S. S.

    2016-10-01

    We report on the influence of silver nanoparticles (NPs) on the luminescence behavior of trivalent rare earth (RE) ion doped tungsten-phosphate glasses. In order to induce the growth of NPs, the as-prepared glass samples containing silver atoms, are exposed to heat-treatment above the glass transition temperature. The surface plasmon resonance band of the Ag NPs is observed in the visible range around 420 and 537 nm in the glasses with low and high tungsten content, respectively. Such difference in spectral shift of the plasmon band is attributed to the difference in the refractive index of the two studied glass compositions. Heat-treatment results in the general increase in number of NPs, while in the case of glasses with low tungsten content, it also imposes a shift to the Ag plasmon band. The NPs size distribution (4-10 nm) was determined in good agreement with the values obtained by using Mie theory and by transmission electron microscopy. The observed quenching in the visible luminescence of glasses doped with Eu3+, Tb3+ or Er3+is attributed to energy transfer from the RE ions to Ag species, while an enhanced near-infrared emission in Er3+ doped glasses is discussed in terms of the chemical contribution of silver, rather than the most commonly claimed enhancement of localized field or energy transfer from silver species to Er3+. The results are supported by the lifetime measurements. We believe that this study gives further insight and in-depth exploration of the somewhat controversial discussions on the influence of metallic NPs plasmonic effects in RE-doped glasses.

  20. Trivalent inactivated influenza vaccine effective against influenza A(H3N2) variant viruses in children during the 2014/15 season, Japan

    Science.gov (United States)

    Sugaya, Norio; Shinjoh, Masayoshi; Kawakami, Chiharu; Yamaguchi, Yoshio; Yoshida, Makoto; Baba, Hiroaki; Ishikawa, Mayumi; Kono, Mio; Sekiguchi, Shinichiro; Kimiya, Takahisa; Mitamura, Keiko; Fujino, Motoko; Komiyama, Osamu; Yoshida, Naoko; Tsunematsu, Kenichiro; Narabayashi, Atsushi; Nakata, Yuji; Sato, Akihiro; Taguchi, Nobuhiko; Fujita, Hisayo; Toki, Machiko; Myokai, Michiko; Ookawara, Ichiro; Takahashi, Takao

    2016-01-01

    The 2014/15 influenza season in Japan was characterised by predominant influenza A(H3N2) activity; 99% of influenza A viruses detected were A(H3N2). Subclade 3C.2a viruses were the major epidemic A(H3N2) viruses, and were genetically distinct from A/New York/39/2012(H3N2) of 2014/15 vaccine strain in Japan, which was classified as clade 3C.1. We assessed vaccine effectiveness (VE) of inactivated influenza vaccine (IIV) in children aged 6 months to 15 years by test-negative case–control design based on influenza rapid diagnostic test. Between November 2014 and March 2015, a total of 3,752 children were enrolled: 1,633 tested positive for influenza A and 42 for influenza B, and 2,077 tested negative. Adjusted VE was 38% (95% confidence intervals (CI): 28 to 46) against influenza virus infection overall, 37% (95% CI: 27 to 45) against influenza A, and 47% (95% CI: -2 to 73) against influenza B. However, IIV was not statistically significantly effective against influenza A in infants aged 6 to 11 months or adolescents aged 13 to 15 years. VE in preventing hospitalisation for influenza A infection was 55% (95% CI: 42 to 64). Trivalent IIV that included A/New York/39/2012(H3N2) was effective against drifted influenza A(H3N2) virus, although vaccine mismatch resulted in low VE. PMID:27784529

  1. Dietary Enterococcus faecium NCIMB 10415 and zinc oxide stimulate immune reactions to trivalent influenza vaccination in pigs but do not affect virological response upon challenge infection.

    Science.gov (United States)

    Wang, Zhenya; Burwinkel, Michael; Chai, Weidong; Lange, Elke; Blohm, Ulrike; Breithaupt, Angele; Hoffmann, Bernd; Twardziok, Sven; Rieger, Juliane; Janczyk, Pawel; Pieper, Robert; Osterrieder, Nikolaus

    2014-01-01

    Swine influenza viruses (SIV) regularly cause significant disease in pigs worldwide. Since there is no causative treatment of SIV, we tested if probiotic Enterococcus (E.) faecium NCIMB 10415 or zinc (Zn) oxide as feed supplements provide beneficial effects upon SIV infection in piglets. Seventy-two weaned piglets were fed three different diets containing either E. faecium or different levels of Zn (2500 ppm, Zn(high); 50 ppm, Zn(low)). Half of the piglets were vaccinated intramuscularly (VAC) twice with an inactivated trivalent SIV vaccine, while all piglets were then infected intranasally with H3N2 SIV. Significantly higher weekly weight gains were observed in the E. faecium group before virus infection, and piglets in Zn(high) and E. faecium groups gained weight after infection while those in the control group (Zn(low)) lost weight. Using ELISA, we found significantly higher H3N2-specific antibody levels in the E. faecium+VAC group 2 days before and at the day of challenge infection as well as at 4 and 6 days after challenge infection. Higher hemagglutination inhibition (HI) titers were also observed in the Zn(high)+VAC and E. faecium+VAC groups at 0, 1 and 4 days after infection. However, there were no significant differences in virus shedding and lung lesions between the dietary groups. Using flow cytometry analysis significantly higher activated T helper cells and cytotoxic T lymphocyte percentages in the PBMCs were detected in the Zn(high) and E. faecium groups at single time points after infection compared to the Zn(low) control group, but no prolonged effect was found. In the BAL cells no influence of dietary supplementation on immune cell percentages could be detected. Our results suggest that feeding high doses of zinc oxide and particularly E. faecium could beneficially influence humoral immune responses after vaccination and recovery from SIV infection, but not affect virus shedding and lung pathology.

  2. Dietary Enterococcus faecium NCIMB 10415 and zinc oxide stimulate immune reactions to trivalent influenza vaccination in pigs but do not affect virological response upon challenge infection.

    Directory of Open Access Journals (Sweden)

    Zhenya Wang

    Full Text Available Swine influenza viruses (SIV regularly cause significant disease in pigs worldwide. Since there is no causative treatment of SIV, we tested if probiotic Enterococcus (E. faecium NCIMB 10415 or zinc (Zn oxide as feed supplements provide beneficial effects upon SIV infection in piglets. Seventy-two weaned piglets were fed three different diets containing either E. faecium or different levels of Zn (2500 ppm, Zn(high; 50 ppm, Zn(low. Half of the piglets were vaccinated intramuscularly (VAC twice with an inactivated trivalent SIV vaccine, while all piglets were then infected intranasally with H3N2 SIV. Significantly higher weekly weight gains were observed in the E. faecium group before virus infection, and piglets in Zn(high and E. faecium groups gained weight after infection while those in the control group (Zn(low lost weight. Using ELISA, we found significantly higher H3N2-specific antibody levels in the E. faecium+VAC group 2 days before and at the day of challenge infection as well as at 4 and 6 days after challenge infection. Higher hemagglutination inhibition (HI titers were also observed in the Zn(high+VAC and E. faecium+VAC groups at 0, 1 and 4 days after infection. However, there were no significant differences in virus shedding and lung lesions between the dietary groups. Using flow cytometry analysis significantly higher activated T helper cells and cytotoxic T lymphocyte percentages in the PBMCs were detected in the Zn(high and E. faecium groups at single time points after infection compared to the Zn(low control group, but no prolonged effect was found. In the BAL cells no influence of dietary supplementation on immune cell percentages could be detected. Our results suggest that feeding high doses of zinc oxide and particularly E. faecium could beneficially influence humoral immune responses after vaccination and recovery from SIV infection, but not affect virus shedding and lung pathology.

  3. The effect of age and recent influenza vaccination history on the immunogenicity and efficacy of 2009-10 seasonal trivalent inactivated influenza vaccination in children.

    Directory of Open Access Journals (Sweden)

    Sophia Ng

    Full Text Available There is some evidence that annual vaccination of trivalent inactivated influenza vaccine (TIV may lead to reduced vaccine immunogenicity but evidence is lacking on whether vaccine efficacy is affected by prior vaccination history. The efficacy of one dose of TIV in children 6-8 y of age against influenza B is uncertain. We examined whether immunogenicity and efficacy of influenza vaccination in school-age children varied by age and past vaccination history.We conducted a randomized controlled trial of 2009-10 TIV. Influenza vaccination history in the two preceding years was recorded. Immunogenicity was assessed by comparison of HI titers before and one month after receipt of TIV/placebo. Subjects were followed up for 11 months with symptom diaries, and respiratory specimens were collected during acute respiratory illnesses to permit confirmation of influenza virus infections. We found that previous vaccination was associated with reduced antibody responses to TIV against seasonal A(H1N1 and A(H3N2 particularly in children 9-17 y of age, but increased antibody responses to the same lineage of influenza B virus in children 6-8 y of age. Serological responses to the influenza A vaccine viruses were high regardless of vaccination history. One dose of TIV appeared to be efficacious against confirmed influenza B in children 6-8 y of age regardless of vaccination history.Prior vaccination was associated with lower antibody titer rises following vaccination against seasonal influenza A vaccine viruses, but higher responses to influenza B among individuals primed with viruses from the same lineage in preceding years. In a year in which influenza B virus predominated, no impact of prior vaccination history was observed on vaccine efficacy against influenza B. The strains that circulated in the year of study did not allow us to study the effect of prior vaccination on vaccine efficacy against influenza A.

  4. Methyl iodide tests on used adsorbents

    International Nuclear Information System (INIS)

    Kovach, J.L.

    1993-01-01

    This paper discusses the history of events leading to the current problems in radioiodine test conditions. These radioiodine tests are performed in the adsorbent media from both safety and non-safety related Nuclear Air Treatment Systems (NATS). The main problem addressed is that currently there are still numerous plant technical specifications for NATS which reference outdated test protocols for the surveillance testing of the radioactive methyl iodide performance of the adsorbents. Recommendations for correcting the test condition problems are presented. 7 refs

  5. Increased radiation degradation in methyl methacrylate copolymers

    International Nuclear Information System (INIS)

    Helbert, J.N; Wagner, G.E.; Caplan, P.J.; Poindexter, E.H.

    1975-01-01

    The effect of polar substituents at the quaternary carbon on degradation processes in several polymers and 10 to 20 percent copolymers of methyl methacrylate was explored. EPR was used to monitor radiation degradation products and to determine radiation G values. Irradiations were carried out at 77 0 K in a gamma irradiator at a dose rate of 0.3 Mrad/hr. (U.S.)

  6. Kinetics of enzymatic hydrolysis of methyl ricinoleate

    OpenAIRE

    Neeharika, T. S.V.R.; Lokesh, P.; Prasanna Rani, K. N.; Prathap Kumar, T.; Prasad, R. B.N.

    2015-01-01

    Ricinoleic acid is an unsaturated hydroxy fatty acid that naturally occurs in castor oil in proportions of up to 85–90%. Ricinoleic acid is a potential raw material and finds several applications in coatings, lubricant formulations and pharmaceutical areas. Enzymatic hydrolysis of castor oil is preferred over conventional hydrolysis for the preparation of ricinoleic acid to avoid estolide formation. A kinetics analysis of the enzymatic hydrolysis of Methyl Ricinoleate in the presence of Candi...

  7. Liberation of methyl acrylate from metallalactone complexes via M-O ring opening (M = Ni, Pd) with methylation agents

    KAUST Repository

    Lee, S. Y Tina; Ghani, Amylia Abdul; D'Elia, Valerio; Cokoja, Mirza; Herrmann, Wolfgang A.; Basset, Jean-Marie; Kü hn, Fritz

    2013-01-01

    Ring opening of various nickela- and palladalactones induced by the cleavage of the M-O bond by methyl trifluoromethanesulfonate (MeOTf) and methyl iodide (MeI) is examined. Experimental evidence supports the mechanism of ring opening by the alkylating agent followed by β-H elimination leading to methyl acrylate and a metal-hydride species. MeOTf shows by far higher efficiency in the lactone ring opening than any other methylating agent including the previously reported methyl iodide. © 2013 The Royal Society of Chemistry and the Centre National de la Recherche Scientifique.

  8. Dynamic instability of genomic methylation patterns in pluripotent stem cells

    Directory of Open Access Journals (Sweden)

    Ooi Steen KT

    2010-09-01

    Full Text Available Abstract Background Genomic methylation patterns are established during gametogenesis, and perpetuated in somatic cells by faithful maintenance methylation. There have been previous indications that genomic methylation patterns may be less stable in embryonic stem (ES cells than in differentiated somatic cells, but it is not known whether different mechanisms of de novo and maintenance methylation operate in pluripotent stem cells compared with differentiating somatic cells. Results In this paper, we show that ablation of the DNA methyltransferase regulator DNMT3L (DNA methyltransferase 3-like in mouse ES cells renders them essentially incapable of de novo methylation of newly integrated retroviral DNA. We also show that ES cells lacking DNMT3L lose DNA methylation over time in culture, suggesting that DNA methylation in ES cells is the result of dynamic loss and gain of DNA methylation. We found that wild-type female ES cells lose DNA methylation at a much faster rate than do male ES cells; this defect could not be attributed to sex-specific differences in expression of DNMT3L or of any DNA methyltransferase. We also found that human ES and induced pluripotent stem cell lines showed marked but variable loss of methylation that could not be attributed to sex chromosome constitution or time in culture. Conclusions These data indicate that DNA methylation in pluripotent stem cells is much more dynamic and error-prone than is maintenance methylation in differentiated cells. DNA methylation requires DNMT3L in stem cells, but DNMT3L is not expressed in differentiating somatic cells. Error-prone maintenance methylation will introduce unpredictable phenotypic variation into clonal populations of pluripotent stem cells, and this variation is likely to be much more pronounced in cultured female cells. This epigenetic variability has obvious negative implications for the clinical applications of stem cells.

  9. Quantitative DNA methylation analysis of candidate genes in cervical cancer.

    Directory of Open Access Journals (Sweden)

    Erin M Siegel

    Full Text Available Aberrant DNA methylation has been observed in cervical cancer; however, most studies have used non-quantitative approaches to measure DNA methylation. The objective of this study was to quantify methylation within a select panel of genes previously identified as targets for epigenetic silencing in cervical cancer and to identify genes with elevated methylation that can distinguish cancer from normal cervical tissues. We identified 49 women with invasive squamous cell cancer of the cervix and 22 women with normal cytology specimens. Bisulfite-modified genomic DNA was amplified and quantitative pyrosequencing completed for 10 genes (APC, CCNA, CDH1, CDH13, WIF1, TIMP3, DAPK1, RARB, FHIT, and SLIT2. A Methylation Index was calculated as the mean percent methylation across all CpG sites analyzed per gene (~4-9 CpG site per sequence. A binary cut-point was defined at >15% methylation. Sensitivity, specificity and area under ROC curve (AUC of methylation in individual genes or a panel was examined. The median methylation index was significantly higher in cases compared to controls in 8 genes, whereas there was no difference in median methylation for 2 genes. Compared to HPV and age, the combination of DNA methylation level of DAPK1, SLIT2, WIF1 and RARB with HPV and age significantly improved the AUC from 0.79 to 0.99 (95% CI: 0.97-1.00, p-value = 0.003. Pyrosequencing analysis confirmed that several genes are common targets for aberrant methylation in cervical cancer and DNA methylation level of four genes appears to increase specificity to identify cancer compared to HPV detection alone. Alterations in DNA methylation of specific genes in cervical cancers, such as DAPK1, RARB, WIF1, and SLIT2, may also occur early in cervical carcinogenesis and should be evaluated.

  10. DNA methylation signatures of educational attainment

    Science.gov (United States)

    van Dongen, Jenny; Bonder, Marc Jan; Dekkers, Koen F.; Nivard, Michel G.; van Iterson, Maarten; Willemsen, Gonneke; Beekman, Marian; van der Spek, Ashley; van Meurs, Joyce B. J.; Franke, Lude; Heijmans, Bastiaan T.; van Duijn, Cornelia M.; Slagboom, P. Eline; Boomsma, Dorret I.; BIOS consortium

    2018-03-01

    Educational attainment is a key behavioural measure in studies of cognitive and physical health, and socioeconomic status. We measured DNA methylation at 410,746 CpGs (N = 4152) and identified 58 CpGs associated with educational attainment at loci characterized by pleiotropic functions shared with neuronal, immune and developmental processes. Associations overlapped with those for smoking behaviour, but remained after accounting for smoking at many CpGs: Effect sizes were on average 28% smaller and genome-wide significant at 11 CpGs after adjusting for smoking and were 62% smaller in never smokers. We examined sources and biological implications of education-related methylation differences, demonstrating correlations with maternal prenatal folate, smoking and air pollution signatures, and associations with gene expression in cis, dynamic methylation in foetal brain, and correlations between blood and brain. Our findings show that the methylome of lower-educated people resembles that of smokers beyond effects of their own smoking behaviour and shows traces of various other exposures.

  11. Neural Tube Defects, Folic Acid and Methylation

    Science.gov (United States)

    Imbard, Apolline; Benoist, Jean-François; Blom, Henk J.

    2013-01-01

    Neural tube defects (NTDs) are common complex congenital malformations resulting from failure of the neural tube closure during embryogenesis. It is established that folic acid supplementation decreases the prevalence of NTDs, which has led to national public health policies regarding folic acid. To date, animal studies have not provided sufficient information to establish the metabolic and/or genomic mechanism(s) underlying human folic acid responsiveness in NTDs. However, several lines of evidence suggest that not only folates but also choline, B12 and methylation metabolisms are involved in NTDs. Decreased B12 vitamin and increased total choline or homocysteine in maternal blood have been shown to be associated with increased NTDs risk. Several polymorphisms of genes involved in these pathways have also been implicated in risk of development of NTDs. This raises the question whether supplementation with B12 vitamin, betaine or other methylation donors in addition to folic acid periconceptional supplementation will further reduce NTD risk. The objective of this article is to review the role of methylation metabolism in the onset of neural tube defects. PMID:24048206

  12. Fragrance material review on cyclohexyl methyl pentanone.

    Science.gov (United States)

    Scognamiglio, J; Letizia, C S; Api, A M

    2013-12-01

    A toxicologic and dermatologic review of cyclohexyl methyl pentanone when used as a fragrance ingredient is presented. Cyclohexyl methyl pentanone is a member of the fragrance structural group Alkyl Cyclic Ketones. These fragrances can be described as being composed of an alkyl, R1, and various substituted and bicyclic saturated or unsaturated cyclic hydrocarbons, R2, in which one of the rings may include up to 12 carbons. Alternatively, R2 may be a carbon bridge of C2-C4 carbon chain length between the ketone and cyclic hydrocarbon. This review contains a detailed summary of all available toxicology and dermatology papers that are related to this individual fragrance ingredient and is not intended as a stand-alone document. Available data for cyclohexyl methyl pentanone were evaluated then summarized and includes physical properties, acute toxicity, skin irritation, mucous membrane (eye) irritation, skin sensitization, phototoxicity, photoallergy, and genotoxicity data. A safety assessment of the entire Alkyl Cyclic Ketones will be published simultaneously with this document; please refer to Belsito et al. (Belsito, D., Bickers, D., Bruze, M., Calow, P., Dagli, M., Fryer, A.D., Greim, H., Miyachi, Y., Saurat, J.H., Sipes, I.G., 2013. A toxicologic and dermatologic assessment of alkyl cyclic ketones when used as fragrance ingredients (submitted for publication).) for an overall assessment of the safe use of this material and all Alkyl Cyclic Ketones in fragrances. Copyright © 2013. Published by Elsevier Ltd.

  13. [Analysis of genomic DNA methylation level in radish under cadmium stress by methylation-sensitive amplified polymorphism technique].

    Science.gov (United States)

    Yang, Jin-Lan; Liu, Li-Wang; Gong, Yi-Qin; Huang, Dan-Qiong; Wang, Feng; He, Ling-Li

    2007-06-01

    The level of cytosine methylation induced by cadmium in radish (Raphanus sativus L.) genome was analysed using the technique of methylation-sensitive amplified polymorphism (MSAP). The MSAP ratios in radish seedling exposed to cadmium chloride at the concentration of 50, 250 and 500 mg/L were 37%, 43% and 51%, respectively, and the control was 34%; the full methylation levels (C(m)CGG in double strands) were at 23%, 25% and 27%, respectively, while the control was 22%. The level of increase in MSAP and full methylation indicated that de novo methylation occurred in some 5'-CCGG sites under Cd stress. There was significant positive correlation between increase of total DNA methylation level and CdCl(2) concentration. Four types of MSAP patterns: de novo methylation, de-methylation, atypical pattern and no changes of methylation pattern were identified among CdCl(2) treatments and the control. DNA methylation alteration in plants treated with CdCl(2) was mainly through de novo methylation.

  14. Application of a room temperature ionic liquid for nuclear spent fuel reprocessing: speciation of trivalent europium and solvatation effects; Application d'un liquide ionique basse temperature pour les procedes de separation: speciation de l'europium trivalent et effets solvatation

    Energy Technology Data Exchange (ETDEWEB)

    Moutiers, G.; Mekki, S. [CEA Saclay, Dept. de Physico-Chimie, Service de Chimie Physique, 91 - Gif sur Yvette (France); Billard, I. [IN2P3/CNRS, 69 - Villeurbanne (France)

    2007-07-01

    One of the solutions proposed for the optimization of the long term storage and conditioning of spent nuclear fuel is to separate actinide and lanthanide both from each other and from other less radioactive metallic species. The industrial proposed processes, based on liquid liquid extraction steps, involve solvents with non negligible vapour pressure and may generate contaminated liquid wastes that will have to be reprocessed. During the last decade, some room-temperature ionic liquids have been studied and integrated into industrial processes. The interest on this class of solvent came out from their 'green' properties (non volatile, non flammable, recyclable, etc...), but also from the variability of their physico-chemical properties (stability, hydrophobicity, viscosity) as a function of the RTIL chemical composition. Indeed, it has been shown that classical chemical industrial processes could be transferred into those media, even more improved, while a certain number of difficulties arising from using traditional solvent can be avoided. In this respect, it could be promising to investigate the ability to use room temperature ionic liquid into the spent nuclear fuel reprocessing field. The aim of this this study is to test the ability of the specific ionic liquid bumimTf{sub 2}N to allow trivalent europium extraction. The choice of this metal is based on the chemical analogy with trivalent minor actinides Curium and Americium which are contributing the greatest part of the long-lived high level radioactive wastes. Handling these elements needs to be very cautious for the safety and radioprotection aspect. Moreover, europium is a very sensitive luminescent probe to its environment even at the microscopic scale. The report is structured with four parts. In a first chapter, we present the main physico-chemical properties of an imidazolium-based ionic liquid family, and then we choose the ionic liquid bumimTf{sub 2}N for the whole thesis and start with

  15. Methyl group turnover on methyl-accepting chemotaxis proteins during chemotaxis by Bacillus subtilis

    International Nuclear Information System (INIS)

    Thoelke, M.S.; Casper, J.M.; Ordal, G.W.

    1990-01-01

    The addition of attractant to Bacillus subtilis briefly exposed to radioactive methionine causes an increase of labeling of the methyl-accepting chemotaxis proteins. The addition of attractant to cells radiolabeled for longer times shows no change in the extent of methylation. Therefore, the increase in labeling for the briefly labeled cells is due to an increased turnover of methyl groups caused by attractant. All amino acids gave enhanced turnover. This turnover lasted for a prolonged time, probably spanning the period of smooth swimming caused by the attractant addition. Repellent did not affect the turnover when added alone or simultaneously with attractant. Thus, for amino acid attractants, the turnover is probably the excitatory signal, which is seen to extend long into or throughout the adaptation period, not just at the start of it

  16. Production of Methyl Laurate from Coconut Cream through Fractionation of Methyl Ester

    Directory of Open Access Journals (Sweden)

    Johnner P. Sitompul

    2015-10-01

    Full Text Available This paper concerns the production of methyl laurate from coconut cream through fractionation of methyl esters. Coconut oil was produced by wet processing of coconut cream. The esters were prepared by reacting coconut oil and methanol using homogeneous catalyst KOH in a batch reactor, followed by fractionation of fatty acid methyl esters (FAME at various reduced pressures applying differential batch vacuum distillation. Experimental data were compared with simulation of a batch distillation employing the simple Raoult’s model and modified Raoult’s model of phase equilibria. Activity coefficients (γi were determined by optimization to refine the models. The modified Rault’s model with activity coefficients gave better agreement with the experimental data, giving the value of γi between 0,56-0,73. For a given boiling temperature, lower operating pressure produced higher purity of C10 and C12 FAME for respective distillates.

  17. Search for methylation-sensitive amplification polymorphisms in mutant figs.

    Science.gov (United States)

    Rodrigues, M G F; Martins, A B G; Bertoni, B W; Figueira, A; Giuliatti, S

    2013-07-08

    Fig (Ficus carica) breeding programs that use conventional approaches to develop new cultivars are rare, owing to limited genetic variability and the difficulty in obtaining plants via gamete fusion. Cytosine methylation in plants leads to gene repression, thereby affecting transcription without changing the DNA sequence. Previous studies using random amplification of polymorphic DNA and amplified fragment length polymorphism markers revealed no polymorphisms among select fig mutants that originated from gamma-irradiated buds. Therefore, we conducted methylation-sensitive amplified polymorphism analysis to verify the existence of variability due to epigenetic DNA methylation among these mutant selections compared to the main cultivar 'Roxo-de-Valinhos'. Samples of genomic DNA were double-digested with either HpaII (methylation sensitive) or MspI (methylation insensitive) and with EcoRI. Fourteen primer combinations were tested, and on an average, non-methylated CCGG, symmetrically methylated CmCGG, and hemimethylated hmCCGG sites accounted for 87.9, 10.1, and 2.0%, respectively. MSAP analysis was effective in detecting differentially methylated sites in the genomic DNA of fig mutants, and methylation may be responsible for the phenotypic variation between treatments. Further analyses such as polymorphic DNA sequencing are necessary to validate these differences, standardize the regions of methylation, and analyze reads using bioinformatic tools.

  18. DNA methylation in states of cell physiology and pathology.

    Directory of Open Access Journals (Sweden)

    Lech Chyczewski

    2007-10-01

    Full Text Available DNA methylation is one of epigenetic mechanisms regulating gene expression. The methylation pattern is determined during embryogenesis and passed over to differentiating cells and tissues. In a normal cell, a significant degree of methylation is characteristic for extragenic DNA (cytosine within the CG dinucleotide while CpG islands located in gene promoters are unmethylated, except for inactive genes of the X chromosome and the genes subjected to genomic imprinting. The changes in the methylation pattern, which may appear as the organism age and in early stages of cancerogenesis, may lead to the silencing of over ninety endogenic genes. It has been found, that these disorders consist not only of the methylation of CpG islands, which are normally unmethylated, but also of the methylation of other dinucleotides, e.g. CpA. Such methylation has been observed in non-small cell lung cancer, in three regions of the exon 5 of the p53 gene (so-called "non-CpG" methylation. The knowledge of a normal methylation process and its aberrations appeared to be useful while searching for new markers enabling an early detection of cancer. With the application of the Real-Time PCR technique (using primers for methylated and unmethylated sequences five new genes which are potential biomarkers of lung cancer have been presented.

  19. Study by mass spectrometry of the formation of cluster ions generated by laser ablation/ionization of inorganic compounds: application to the differentiation of trivalent and hexavalent chromium compounds

    International Nuclear Information System (INIS)

    Aubriet, Frederic

    1999-01-01

    The introduction of new ionization techniques allows a fast growth of mass spectrometry applications in an increasing number of fields. More particularly, the introduction of laser ablation/ionization process and the design of new instruments (laser microprobes), has been very important for a better knowledge of inorganic compound mass spectrometry. The purposes of this work were mainly focussed firstly in the understanding of cluster ions formation process by laser ablation/ionization and secondly in the development of a new mass spectrometry technique for the speciation between trivalent and hexavalent chromium compounds. We show that cluster ion formation are multiple. The difficulty to identify clearly the processes involved is due to the superposition of many mechanisms. Mostly, these processes are representative of the complexity of the gas-phase chemistry between the various species generated by laser ablation/ionization. Thus, four mechanisms for the cluster ion formation have been highlighted. The most frequently met correspond to aggregative processes of neutral molecules on precursor ions. The knowledge of the processes of cluster ion formation allows us to explain why it is possible to distinguish the oxidation number of chromium. The organigram of chromium valence speciation proposed is based on the calculation of the ratio of negative cluster ion intensities after systematic analysis of nearly twenty chromium reference compounds using the same instrumental conditions. The examination of mixtures between 1) calcium. silicon, trivalent iron or zinc oxides and 2) the standard chromium compound allows us to observe the influence of these oxides on the fingerprints of the pure chromium compounds and to determine up to which point and with which limitations, the methodology suggested, could be applied to the analysis of trivalent and hexavalent chromium compounds in complex and polyphasic matrices

  20. Reaction products from N-methyl-N-nitrosourea and deoxyribonucleic acid containing thymidine residues. Synthesis and identification of a new methylation product, O4-methyl-thymidine

    Science.gov (United States)

    Lawley, P. D.; Orr, D. J.; Shah, S. A.; Farmer, P. B.; Jarman, M.

    1973-01-01

    1. DNA was treated with N-methyl-N-nitrosourea at pH7–8, 37°C, degraded to yield 3- and 7-methylpurines and deoxyribonucleosides and the reaction products were separated by chromatography on ion-exchange resins. The following methods for identification and determination of products were used: with unlabelled N-methyl-N-nitrosourea, u.v. absorption; use of methyl-14C-labelled N-methyl-N-nitrosourea and use of [14C]thymine-labelled DNA. 2. The synthesis of O4-methylthymidine and its identification by u.v. and mass spectroscopy are reported. 3. 3-Methylthymidine and O4-methylthymidine were found as methylation products from N-methyl-N-nitrosourea with thymidine and with DNA, in relatively small yields. Unidentified products containing thymine were found in enzymic digests of N-methyl-N-nitrosourea-treated DNA, which may be phosphotriesters. 4. The possible role of formation of methylthymines in mutagenesis by N-methyl-N-nitrosourea is discussed. PMID:4798180

  1. The ectopic expression of a pectin methyl esterase inhibitor increases pectin methyl esterification and limits fungal diseases in wheat.

    Science.gov (United States)

    Volpi, Chiara; Janni, Michela; Lionetti, Vincenzo; Bellincampi, Daniela; Favaron, Francesco; D'Ovidio, Renato

    2011-09-01

    Cell wall pectin methyl esterification can influence plant resistance because highly methyl-esterified pectin can be less susceptible to the hydrolysis by pectic enzymes such as fungal endopolygalacturonases (PG). Pectin is secreted into the cell wall in a highly methyl-esterified form and, here, is de-methyl esterified by pectin methyl esterase (PME). The activity of PME is controlled by specific protein inhibitors called PMEI; consequently, an increased inhibition of PME by PMEI might modify the pectin methyl esterification. In order to test the possibility of improving wheat resistance by modifying the methyl esterification of pectin cell wall, we have produced durum wheat transgenic lines expressing the PMEI from Actinidia chinensis (AcPMEI). The expression of AcPMEI endows wheat with a reduced endogenous PME activity, and transgenic lines expressing a high level of the inhibitor showed a significant increase in the degree of methyl esterification. These lines showed a significant reduction of disease symptoms caused by the fungal pathogens Bipolaris sorokiniana or Fusarium graminearum. This increased resistance was related to the impaired ability of these fungal pathogens to grow on methyl-esterified pectin and to a reduced activity of the fungal PG to hydrolyze methyl-esterified pectin. In addition to their importance for wheat improvement, these results highlight the primary role of pectin despite its low content in the wheat cell wall.

  2. Structure, function and carcinogenicity of metabolites of methylated and non-methylated polycyclic aromatic hydrocarbons: a comprehensive review.

    Science.gov (United States)

    Flesher, James W; Lehner, Andreas F

    2016-01-01

    The Unified Theory of PAH Carcinogenicity accommodates the activities of methylated and non-methylated polycyclic aromatic hydrocarbons (PAHs) and states that substitution of methyl groups on meso-methyl substituted PAHs with hydroxy, acetoxy, chloride, bromide or sulfuric acid ester groups imparts potent cancer producing properties. It incorporates specific predictions from past researchers on the mechanism of carcinogenesis by methyl-substituted hydrocarbons, including (1) requirement for metabolism to an ArCH2X type structure where X is a good leaving group and (2) biological substitution of a meso-methyl group at the most reactive center in non-methylated hydrocarbons. The Theory incorporates strong inferences of Fieser: (1) The mechanism of carcinogenesis involves a specific metabolic substitution of a hydrocarbon at its most reactive center and (2) Metabolic elimination of a carcinogen is a detoxifying process competitive with that of carcinogenesis and occurring by a different mechanism. According to this outlook, chemical or biochemical substitution of a methyl group at the reactive meso-position of non-methylated hydrocarbons is the first step in the mechanism of carcinogenesis for most, if not all, PAHs and the most potent metabolites of PAHs are to be found among the meso methyl-substituted hydrocarbons. Some PAHs and their known or potential metabolites and closely related compounds have been tested in rats for production of sarcomas at the site of subcutaneous injection and the results strongly support the specific predictions of the Unified Theory.

  3. Relationship between methylation status of vitamin D-related genes, vitamin D levels, and methyl-donor biochemistry

    Directory of Open Access Journals (Sweden)

    Emma Louise Beckett

    2016-12-01

    Full Text Available Vitamin D is known for its role in the regulation of gene expression via the vitamin D receptor, a nuclear transcription factor. More recently, a role for vitamin D in regulating DNA methylation has been identified as an additional mechanism of modulation of gene expression. How methylation status influences vitamin D metabolism and response pathways is not yet clear. Therefore, we aimed to assess the relationship between plasma 25-hydroxycholecalciferol (25(OHD and the methylation status of vitamin D metabolism enzyme genes (CYP2R1, CYP27B1 and CYP24A1 and the vitamin D receptor gene (VDR. This analysis was conducted in the context of dietary vitamin D, and background methyl donor related biochemistry, with adjustment for several dietary and lifestyle variables. Percentage methylation at CpG sites was assessed in peripheral blood cells using methylation sensitive and dependent enzymes and qPCR. Standard analytical techniques were used to determine plasma 25(OHD and homocysteine, and serum folate and B12, with the relationship to methylation status assessed using multi-variable regression analysis. CYP2R1 and VDR methylation were found to be independent predictors of plasma 25(OHD, when adjusted for vitamin D intake and other lifestyle variables. CYP24A1 was related to plasma 25(OHD directly, but not in the context of vitamin D intake. Methyl-group donor biochemistry was associated with the methylation status of some genes, but did not alter the relationship between methylation and plasma 25(OHD. Modulation of methylation status of CYP2R1, CYP24A1 and VDR in response to plasma 25(OHD may be part of feedback loops involved in maintaining vitamin D homeostasis, and may explain a portion of the variance in plasma 25(OHD levels in response to intake and sun exposure. Methyl-group donor biochemistry, while a potential independent modulator, did not alter this effect.

  4. Methylated site display (MSD)-AFLP, a sensitive and affordable method for analysis of CpG methylation profiles.

    Science.gov (United States)

    Aiba, Toshiki; Saito, Toshiyuki; Hayashi, Akiko; Sato, Shinji; Yunokawa, Harunobu; Maruyama, Toru; Fujibuchi, Wataru; Kurita, Hisaka; Tohyama, Chiharu; Ohsako, Seiichiroh

    2017-03-09

    It has been pointed out that environmental factors or chemicals can cause diseases that are developmental in origin. To detect abnormal epigenetic alterations in DNA methylation, convenient and cost-effective methods are required for such research, in which multiple samples are processed simultaneously. We here present methylated site display (MSD), a unique technique for the preparation of DNA libraries. By combining it with amplified fragment length polymorphism (AFLP) analysis, we developed a new method, MSD-AFLP. Methylated site display libraries consist of only DNAs derived from DNA fragments that are CpG methylated at the 5' end in the original genomic DNA sample. To test the effectiveness of this method, CpG methylation levels in liver, kidney, and hippocampal tissues of mice were compared to examine if MSD-AFLP can detect subtle differences in the levels of tissue-specific differentially methylated CpGs. As a result, many CpG sites suspected to be tissue-specific differentially methylated were detected. Nucleotide sequences adjacent to these methyl-CpG sites were identified and we determined the methylation level by methylation-sensitive restriction endonuclease (MSRE)-PCR analysis to confirm the accuracy of AFLP analysis. The differences of the methylation level among tissues were almost identical among these methods. By MSD-AFLP analysis, we detected many CpGs showing less than 5% statistically significant tissue-specific difference and less than 10% degree of variability. Additionally, MSD-AFLP analysis could be used to identify CpG methylation sites in other organisms including humans. MSD-AFLP analysis can potentially be used to measure slight changes in CpG methylation level. Regarding the remarkable precision, sensitivity, and throughput of MSD-AFLP analysis studies, this method will be advantageous in a variety of epigenetics-based research.

  5. Current trends in electrochemical sensing and biosensing of DNA methylation.

    Science.gov (United States)

    Krejcova, Ludmila; Richtera, Lukas; Hynek, David; Labuda, Jan; Adam, Vojtech

    2017-11-15

    DNA methylation plays an important role in physiological and pathological processes. Several genetic diseases and most malignancies tend to be associated with aberrant DNA methylation. Among other analytical methods, electrochemical approaches have been successfully employed for characterisation of DNA methylation patterns that are essential for the diagnosis and treatment of particular diseases. This article discusses current trends in the electrochemical sensing and biosensing of DNA methylation. Particularly, it provides an overview of applied electrode materials, electrode modifications and biorecognition elements applications with an emphasis on strategies that form the core DNA methylation detection approaches. The three main strategies as (i) bisulfite treatment, (ii) cleavage by restriction endonucleases, and (iii) immuno/affinity reaction were described in greater detail. Additionally, the availability of the reviewed platforms for early cancer diagnosis and the approval of methylation inhibitors for anticancer therapy were discussed. Copyright © 2017 Elsevier B.V. All rights reserved.

  6. Methylation of mercury in isopod Porcellio scaber

    International Nuclear Information System (INIS)

    Jereb, V.; Horvat, M.; Cerne, I.; Drobne, D.

    2002-01-01

    Due to some remarkable characteristics, more than a decade ago terrestrial isopods were introduced as biornonitoring organisms for metals in industrially polluted environments. These characteristics are: suitable size, abundance, ease of handling in the laboratory, the ability to accumulate metals (Zn, Cd, Pb) and dose-dependent response to different metals and pesticides (diazinon). The isopod Porcellio scaber is a small terrestrial crab, which colonizes upper soil layers and litter. It lives in a humid environment, mostly under tree-leaves, decaying wood and bigger stones. It is an omnivore, but its most common food is decomposing organic matter. Therefore, isopods are important for decomposition and cycling of mineral matter in nature. Porcellio scaber can be also found on the river banks of river ldrijca a mercury contaminated site, but there is a lack of data on effects of Hg on Porcellio scaber. Therefore, it would be of interest to investigate the biological cycle of mercury in this animal. The objectives of our work were: To assess the magnitudes of biological processes (metal Hg 2+ ) uptake, its retention in the animal, accumulation in glands, excretion of Hg by faeces); To investigate the possibility of mercury transformation in the animal (Hg 2+→ MeHg + ). It is known, that intestine is a possible Hg 2+ methylation site; in the gut of Porcellio scaber are present anaerobes and very likely also sulphate-reducing bacteria, which are known to be responsible for Hg 2+ methylation in nature; To validate an appropriate analytical technique for Hg 2+ methylation assays in the isopod Porcellio scaber

  7. DNA methylation-based variation between human populations.

    Science.gov (United States)

    Kader, Farzeen; Ghai, Meenu

    2017-02-01

    Several studies have proved that DNA methylation affects regulation of gene expression and development. Epigenome-wide studies have reported variation in methylation patterns between populations, including Caucasians, non-Caucasians (Blacks), Hispanics, Arabs, and numerous populations of the African continent. Not only has DNA methylation differences shown to impact externally visible characteristics, but is also a potential biomarker for underlying racial health disparities between human populations. Ethnicity-related methylation differences set their mark during early embryonic development. Genetic variations, such as single-nucleotide polymorphisms and environmental factors, such as age, dietary folate, socioeconomic status, and smoking, impacts DNA methylation levels, which reciprocally impacts expression of phenotypes. Studies show that it is necessary to address these external influences when attempting to differentiate between populations since the relative impacts of these factors on the human methylome remain uncertain. The present review summarises several reported attempts to establish the contribution of differential DNA methylation to natural human variation, and shows that DNA methylation could represent new opportunities for risk stratification and prevention of several diseases amongst populations world-wide. Variation of methylation patterns between human populations is an exciting prospect which inspires further valuable research to apply the concept in routine medical and forensic casework. However, trans-generational inheritance needs to be quantified to decipher the proportion of variation contributed by DNA methylation. The future holds thorough evaluation of the epigenome to understand quantification, heritability, and the effect of DNA methylation on phenotypes. In addition, methylation profiling of the same ethnic groups across geographical locations will shed light on conserved methylation differences in populations.

  8. MECP2 promoter methylation and X chromosome inactivation in autism.

    Science.gov (United States)

    Nagarajan, Raman P; Patzel, Katherine A; Martin, Michelle; Yasui, Dag H; Swanberg, Susan E; Hertz-Picciotto, Irva; Hansen, Robin L; Van de Water, Judy; Pessah, Isaac N; Jiang, Ruby; Robinson, Wendy P; LaSalle, Janine M

    2008-06-01

    Epigenetic mechanisms have been proposed to play a role in the etiology of autism. This hypothesis is supported by the discovery of increased MECP2 promoter methylation associated with decreased MeCP2 protein expression in autism male brain. To further understand the influence of female X chromosome inactivation (XCI) and neighboring methylation patterns on aberrant MECP2 promoter methylation in autism, multiple methylation analyses were peformed on brain and blood samples from individuals with autism. Bisulfite sequencing analyses of a region 0.6 kb upstream of MECP2 in brain DNA samples revealed an abrupt transition from a highly methylated region in both sexes to a region unmethylated in males and subject to XCI in females. Chromatin immunoprecipitation analysis demonstrated that the CCTC-binding factor (CTCF) bound to this transition region in neuronal cells, consistent with a chromatin boundary at the methylation transition. Male autism brain DNA samples displayed a slight increase in methylation in this transition region, suggesting a possible aberrant spreading of methylation into the MECP2 promoter in autism males across this boundary element. In addition, autistic female brain DNA samples showed evidence for aberrant MECP2 promoter methylation as an increase in the number of bisulfite sequenced clones with undefined XCI status for MECP2 but not androgen receptor (AR). To further investigate the specificity of MECP2 methylation alterations in autism, blood DNA samples from females and mothers of males with autism were also examined for XCI skewing at AR, but no significant increase in XCI skewing was observed compared to controls. These results suggest that the aberrant MECP2 methylation in autism brain DNA samples is due to locus-specific rather than global X chromosome methylation changes.

  9. Methylated spirit burns following traditional hair dressing practice.

    Science.gov (United States)

    Michael, Afieharo I; Iyun, Ayodele O

    2018-02-01

    Methylated spirit burns have been reported following domestic uses such as igniting fondues. It has also been used as an accelerant for self-immolation. We report the first documented case of severe methylated spirit burns sustained during traditional hair dressing. Increased awareness on the dangers of methylated spirit as well as making it less readily available for domestic use is warranted. Copyright © 2016 Elsevier Ltd and ISBI. All rights reserved.

  10. Methylated DNA Immunoprecipitation Analysis of Mammalian Endogenous Retroviruses.

    Science.gov (United States)

    Rebollo, Rita; Mager, Dixie L

    2016-01-01

    Endogenous retroviruses are repetitive sequences found abundantly in mammalian genomes which are capable of modulating host gene expression. Nevertheless, most endogenous retrovirus copies are under tight epigenetic control via histone-repressive modifications and DNA methylation. Here we describe a common method used in our laboratory to detect, quantify, and compare mammalian endogenous retrovirus DNA methylation. More specifically we describe methylated DNA immunoprecipitation (MeDIP) followed by quantitative PCR.

  11. Disinfectant effect of Methylated Ethanol against Listeria species

    OpenAIRE

    Y Yakubu; M D Salihu; O O Faleke; M B Abubakar; A A Magaji,A U Junaidu

    2012-01-01

    This study was carried out in order to determine the disinfectant effect of Methylated spirit® (95% methanol and 5% ethanol) as a teat dip against Listeria species. Hand milking was employed to collect 576 (288 x 2) raw milk samples from different lactating cows within Sokoto metropolis (Nigeria). 288 samples were collected before disinfecting the udder teats with Methylated spirit®, while the other 288 were collected after disinfection with Methylated spirit®. The ...

  12. DNA damage, homology-directed repair, and DNA methylation.

    Directory of Open Access Journals (Sweden)

    Concetta Cuozzo

    2007-07-01

    Full Text Available To explore the link between DNA damage and gene silencing, we induced a DNA double-strand break in the genome of Hela or mouse embryonic stem (ES cells using I-SceI restriction endonuclease. The I-SceI site lies within one copy of two inactivated tandem repeated green fluorescent protein (GFP genes (DR-GFP. A total of 2%-4% of the cells generated a functional GFP by homology-directed repair (HR and gene conversion. However, approximately 50% of these recombinants expressed GFP poorly. Silencing was rapid and associated with HR and DNA methylation of the recombinant gene, since it was prevented in Hela cells by 5-aza-2'-deoxycytidine. ES cells deficient in DNA methyl transferase 1 yielded as many recombinants as wild-type cells, but most of these recombinants expressed GFP robustly. Half of the HR DNA molecules were de novo methylated, principally downstream to the double-strand break, and half were undermethylated relative to the uncut DNA. Methylation of the repaired gene was independent of the methylation status of the converting template. The methylation pattern of recombinant molecules derived from pools of cells carrying DR-GFP at different loci, or from an individual clone carrying DR-GFP at a single locus, was comparable. ClustalW analysis of the sequenced GFP molecules in Hela and ES cells distinguished recombinant and nonrecombinant DNA solely on the basis of their methylation profile and indicated that HR superimposed novel methylation profiles on top of the old patterns. Chromatin immunoprecipitation and RNA analysis revealed that DNA methyl transferase 1 was bound specifically to HR GFP DNA and that methylation of the repaired segment contributed to the silencing of GFP expression. Taken together, our data support a mechanistic link between HR and DNA methylation and suggest that DNA methylation in eukaryotes marks homologous recombined segments.

  13. Thermodynamic study of 2-methyl-tetrahydrofuran with isomeric chlorobutanes

    International Nuclear Information System (INIS)

    Aldea, M. Eugenia; Martin, Santiago; Artigas, Hector; Lopez, Maria C.; Lafuente, Carlos

    2005-01-01

    Excess molar volumes, V E , isentropic compressibility deviations, Δκ S , and excess molar enthalpies, H E , for the binary mixtures 2-methyl-tetrahydrofuran with 1-chlorobutane, 2-chlorobutane, 2-methyl-1-chloropropane and 2-methyl-2-chloropropane have been determined at temperatures 298.15 and 313.15 K, excess molar enthalpies were only measured at 298.15 K. We have applied the Prigogine-Flory-Patterson (PFP) theory to these mixtures at 298.15 K

  14. 21 CFR 172.872 - Methyl ethyl cellulose.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Methyl ethyl cellulose. 172.872 Section 172.872... CONSUMPTION Multipurpose Additives § 172.872 Methyl ethyl cellulose. The food additive methyl ethyl cellulose... a cellulose ether having the general formula [C6H(10 -x-y)O5(CH3)x(C2H5)y]n, where x is the number...

  15. A comprehensive study of methyl decanoate pyrolysis

    International Nuclear Information System (INIS)

    Pyl, Steven P.; Van Geem, Kevin M.; Puimège, Philip; Sabbe, Maarten K.; Reyniers, Marie-Françoise; Marin, Guy B.

    2012-01-01

    The thermal decomposition of methyl decanoate (MD) was studied in a bench-scale pyrolysis set-up equipped with a dedicated on-line analysis section including a GC × GC-FID/(TOF-MS). This analysis section enables quantitative and qualitative on-line analyses of the entire reactor effluent with high level of detail including measurement of formaldehyde and water. The reactor temperature was varied from 873 K to 1123 K at a fixed pressure of 1.7 bar and a fixed residence time of 0.5 s, for both high (10mol N 2 /mol MD ) and low (0.6mol N 2 /mol MD ) nitrogen dilution. Thus covering a wide conversion range in both dilution regimes. In these experiments, significant amounts of large linear olefins and unsaturated esters were observed at lower temperatures, the amounts of which decreased at higher temperatures in favor of permanent gasses (CO, CO 2 , CH 4 ) and light olefins. At the highest temperatures more than 5 wt% of mono-aromatic and poly-aromatic components were observed. The acquired dataset was used to validate 3 recently published microkinetic models which were developed to model oxidation and/or pyrolysis of methyl decanoate. The results showed that these models accurately predict the product distribution, although important discrepancies were observed for some major products such as certain unsaturated esters, CO 2 and H 2 O. Reaction path analyses and CBS-QB3 quantum-chemical calculations are presented and discussed in order to explain the observed differences. -- Highlights: ► New extensive experimental dataset for the pyrolysis of methyl decanoate in a tubular reactor. ► A dedicated separation section including on-line GC × GC allows to obtain quantitative data for over 150 components. ► High level ab-initio calculations for important reactions of the methyl decanoate decomposition. ► Identification of missing reactions/reaction families/inaccurate kinetics in the presently available kinetic models.

  16. Method to remove methyl iodide131 gas

    International Nuclear Information System (INIS)

    Deitz, V.R.; Blachly, C.H.

    1977-01-01

    A two-stage impregnation process for charcoal is presented which is to be used for radioactive iodine or methyl iodide removal from the waste gas of a nuclear reactor. In the first stage, the coal is treated at pH 10 with an aqueous mixture of a salt of iodic acid (hypoiodite, iodate, or periodate) with iodine or iodide. In the second stage, impregnation with a tertiary amine occurs. The concentrations are chosen so that the charcoal will take up between 0.5 and 4% by weight of iodine. (UWI) [de

  17. Sorption of trivalent lanthanides and actinides onto montmorillonite: Macroscopic, thermodynamic and structural evidence for ternary hydroxo and carbonato surface complexes on multiple sorption sites.

    Science.gov (United States)

    Fernandes, M Marques; Scheinost, A C; Baeyens, B

    2016-08-01

    The credibility of long-term safety assessments of radioactive waste repositories may be greatly enhanced by a molecular level understanding of the sorption processes onto individual minerals present in the near- and far-fields. In this study we couple macroscopic sorption experiments to surface complexation modelling and spectroscopic investigations, including extended X-ray absorption fine structure (EXAFS) and time-resolved laser fluorescence spectroscopies (TRLFS), to elucidate the uptake mechanism of trivalent lanthanides and actinides (Ln/An(III)) by montmorillonite in the absence and presence of dissolved carbonate. Based on the experimental sorption isotherms for the carbonate-free system, the previously developed 2 site protolysis non electrostatic surface complexation and cation exchange (2SPNE SC/CE) model needed to be complemented with an additional surface complexation reaction onto weak sites. The fitting of sorption isotherms in the presence of carbonate required refinement of the previously published model by reducing the strong site capacity and by adding the formation of Ln/An(III)-carbonato complexes both on strong and weak sites. EXAFS spectra of selected Am samples and TRLFS spectra of selected Cm samples corroborate the model assumptions by showing the existence of different surface complexation sites and evidencing the formation of Ln/An(III) carbonate surface complexes. In the absence of carbonate and at low loadings, Ln/An(III) form strong inner-sphere complexes through binding to three Al(O,OH)6 octahedra, most likely by occupying vacant sites in the octahedral layers of montmorillonite, which are exposed on {010} and {110} edge faces. At higher loadings, Ln/An(III) binds to only one Al octahedron, forming a weaker, edge-sharing surface complex. In the presence of carbonate, we identified a ternary mono- or dicarbonato Ln/An(III) complex binding directly to one Al(O,OH)6 octahedron, revealing that type-A ternary complexes form with the one

  18. Synthesis and in vitro/in vivo evaluation of novel mono- and trivalent technetium-99m labeled ghrelin peptide complexes as potential diagnostic radiopharmaceuticals

    International Nuclear Information System (INIS)

    Koźmiński, Przemysław; Gniazdowska, Ewa

    2015-01-01

    Introduction: Ghrelin is an endogenous hormone present in blood. It is released from the oxyntic cells (X/A-like cells) of the stomach and fundus and can exist in two forms: as an acylated and des-acylated ghrelin. Ghrelin is an endogenous ligand of the growth hormone receptor (growth hormone secretagogue receptor, GHS-R). Overexpression of GHS-R1a receptor was identified in cells of different types of tumors (e.g. pituitary adenoma, neuroendocrine tumors of the thyroid, lung, breast, gonads, prostate, stomach, colorectal, endocrine and non-endocrine pancreatic tumors). This fact suggests that gamma radionuclide labeled ghrelin peptide may be considered as a potential diagnostic radiopharmaceutical. Methods: Ghrelin peptide labeled with mono- and trivalent technetium-99m complexes, 99m Tc-Lys-GHR, has been prepared on the n.c.a. scale. The physicochemical (stability, charge, shape, lipophilicity) and biological (receptor affinity, biodistribution) properties of the conjugates have been studied relevant to use the conjugates as receptor-based diagnostic radiopharmaceuticals. Results: The obtained conjugates [ 99m Tc(CO) 3 L N,O (CN-Lys-GHR)] + , 99m Tc(CO) 3 L S,O (CN-Lys-GHR) and 99m Tc(NS 3 )(CN-Lys-GHR) show different shape, charge, lipophilicity and two of them, 99m Tc(CO) 3 L S,O (CN-Lys-GHR) and 99m Tc(NS 3 )(CN-Lys-GHR), high stability in neutral aqueous solutions, even in the presence of excess concentration of histidine/cysteine competitive standard ligands or human serum. The in vitro binding affinity of 99m Tc-Lys-GHR conjugates with respect to growth hormone secretagogue receptor (GHS-R1a) present on DU-145 cells was in the range of IC 50 from 45 to 54 nM. The conjugate 99m Tc(CO) 3 L S,O (CN-Lys-GHR) exhibited excretion route by the liver and kidney in comparable degree, while the more lipophilic conjugate 99m Tc(NS 3 )(CN-Lys-GHR)—mainly by the liver. Conclusions: Basing on the results concerning physicochemical and biochemical properties, the

  19. Safety of Russian-backbone seasonal trivalent, live-attenuated influenza vaccine in a phase II randomized placebo-controlled clinical trial among children in urban Bangladesh.

    Science.gov (United States)

    Ortiz, Justin R; Goswami, Doli; Lewis, Kristen D C; Sharmeen, Amina Tahia; Ahmed, Moshtaq; Rahman, Mustafizur; Rahman, Mohammed Z; Feser, Jodi; Neuzil, Kathleen M; Brooks, W Abdullah

    2015-06-26

    Live-attenuated influenza vaccines (LAIVs) have the potential to be affordable, effective, and logistically feasible for immunization of children in low-resource settings. We conducted a phase II, randomized, double-blind, parallel group, placebo-controlled trial on the safety of the Russian-backbone, seasonal trivalent LAIV among children aged 24 through 59 months in Dhaka, Bangladesh in 2012. After vaccination, we monitored participants for six months with weekly home visits and study clinic surveillance for solicited and unsolicited adverse events, protocol-defined wheezing illness (PDWI), and serious adverse events (SAEs), including all cause hospitalizations. Three hundred children were randomized and administered LAIV (n=150) or placebo (n=150). No immediate post-vaccination reactions occurred in either group. Solicited reactions were similar between vaccine and placebo groups during the first 7 days post-vaccination and throughout the entire trial. There were no statistically significant differences in participants experiencing PDWI between LAIV and placebo groups throughout the trial (n=13 vs. n=16, p=0.697). Of 131 children with a history of medical treatment or hospitalization for asthma or wheezing at study entry, 65 received LAIV and 66 received placebo. Among this subset, there was no statistical difference in PDWI occurring throughout the trial between the LAIV or placebo groups (7.7% vs. 19.7%, p=0.074). While there were no related SAEs, LAIV recipients had six unrelated SAEs and placebo recipients had none. These SAEs included three due to traumatic injury and bone fracture, and one each due to accidental overdose of paracetamol, abdominal pain, and acute gastroenteritis. None of the participants with SAEs had laboratory-confirmed influenza, wheezing illness, or other signs of acute respiratory illness at the time of their events. In this randomized, controlled trial among 300 children aged 24 through 59 months in urban Bangladesh, Russian

  20. Luminescence and photo-thermally stimulated defects creation processes in PbWO{sub 4} crystals doped with trivalent rare-earth ions

    Energy Technology Data Exchange (ETDEWEB)

    Fabeni, P. [Institute of Applied Physics “N.Carrara” (IFAC) of CNR, Via Madonna del Piano 10, 50019 Sesto Fiorentino (Firenze) (Italy); Krasnikov, A.; Kärner, T. [Institute of Physics, University of Tartu, Riia 142, 51014 Tartu (Estonia); Laguta, V.V.; Nikl, M. [Institute of Physics AS CR, Cukrovarnicka 10, 16253 Prague (Czech Republic); Pazzi, G.P. [Institute of Applied Physics “N.Carrara” (IFAC) of CNR, Via Madonna del Piano 10, 50019 Sesto Fiorentino (Firenze) (Italy); Zazubovich, S., E-mail: svet@fi.tartu.ee [Institute of Physics, University of Tartu, Riia 142, 51014 Tartu (Estonia)

    2013-04-15

    In PbWO{sub 4} crystals, doped with various trivalent rare-earth A{sup 3+} ions (A{sup 3+}: La{sup 3+}, Lu{sup 3+}, Y{sup 3+}, Ce{sup 3+}, Gd{sup 3+}), electron (WO{sub 4}){sup 3−} and {(WO_4)"3"−–A"3"+} centers can be created under UV irradiation not only in the host absorption region but also in the energy range around 3.85 eV (Böhm et al., 1999; Krasnikov et al., 2010). Under excitation in the same energy range, the UV emission peak at 3.05–3.20 eV is observed. In the present work, the origin of this emission is investigated in detail by low-temperature time-resolved luminescence methods. Photo-thermally stimulated creation of (WO{sub 4}){sup 3−} and {(WO_4)"3"−–A"3"+} centers is studied also in PbWO{sub 4}:Mo,A{sup 3+} crystals. Various processes, which could explain both the appearance of the UV emission and the creation of the {(WO_4)"3"−–A"3"+}-type centers under irradiation of PbWO{sub 4}: A{sup 3+} crystals in the 3.85±0.35 eV energy range, are discussed. The radiative and non-radiative decay of the excitons localized near A{sup 3+} ions is considered as the most probable mechanism to explain the observed features. -- Highlights: ► UV emission of PbWO{sub 4}: A{sup 3+} (A{sup 3+}: La{sup 3+}, Lu{sup 3+}, Y{sup 3+}, Ce{sup 3+}, and Gd{sup 3+}) crystals is studied. ► The emission is ascribed to the radiative decay of excitons localized near A{sup 3+} ions. ► The excitons are created at 3.85 eV excitation by a two-step process. ► Non-radiative decay of the excitons leads to the creation of (WO{sub 4}){sup 3−}–A{sup 3+} centers.

  1. Formation of Methyl Acrylate from CO 2 and Ethylene via Methylation of Nickelalactones

    KAUST Repository

    Bruckmeier, Christian

    2010-05-24

    The nickel-induced coupling of ethylene and CO2 represents a promising pathway toward acrylates. To overcome the high bond dissociation energies of the M-O moieties, we worked out an in situ methylation of nickelalactones to realize the β-hydride elimination and the liberation of the acrylate species. © 2010 American Chemical Society.

  2. Osteoponin Promoter Controlled by DNA Methylation: Aberrant Methylation in Cloned Porcine Genome

    Directory of Open Access Journals (Sweden)

    Chih-Jie Shen

    2014-01-01

    Full Text Available Cloned animals usually exhibited many defects in physical characteristics or aberrant epigenetic reprogramming, especially in some important organ development. Osteoponin (OPN is an extracellular-matrix protein involved in heart and bone development and diseases. In this study, we investigated the correlation between OPN mRNA and its promoter methylation changes by the 5-aza-dc treatment in fibroblast cell and promoter assay. Aberrant methylation of porcine OPN was frequently found in different tissues of somatic nuclear transferred cloning pigs, and bisulfite sequence data suggested that the OPN promoter region −2615 to −2239 nucleotides (nt may be a crucial regulation DNA element. In pig ear fibroblast cell culture study, the demethylation of OPN promoter was found in dose-dependent response of 5-aza-dc treatment and followed the OPN mRNA reexpression. In cloned pig study, discrepant expression pattern was identified in several cloned pig tissues, especially in brain, heart, and ear. Promoter assay data revealed that four methylated CpG sites presenting in the −2615 to −2239 nt region cause significant downregulation of OPN promoter activity. These data suggested that methylation in the OPN promoter plays a crucial role in the regulation of OPN expression that we found in cloned pigs genome.

  3. HIGHLY METHYL ESTERIFIED SEEDS is a pectin methyl esterase involved in embryo development.

    Science.gov (United States)

    Levesque-Tremblay, Gabriel; Müller, Kerstin; Mansfield, Shawn D; Haughn, George W

    2015-03-01

    Homogalacturonan pectin domains are synthesized in a highly methyl-esterified form that later can be differentially demethyl esterified by pectin methyl esterase (PME) to strengthen or loosen plant cell walls that contain pectin, including seed coat mucilage, a specialized secondary cell wall of seed coat epidermal cells. As a means to identify the active PMEs in seed coat mucilage, we identified seven PMEs expressed during seed coat development. One of these, HIGHLY METHYL ESTERIFIED SEEDS (HMS), is abundant during mucilage secretion, peaking at 7 d postanthesis in both the seed coat and the embryo. We have determined that this gene is required for normal levels of PME activity and homogalacturonan methyl esterification in the seed. The hms-1 mutant displays altered embryo morphology and mucilage extrusion, both of which are a consequence of defects in embryo development. A significant decrease in the size of cells in the embryo suggests that the changes in embryo morphology are a consequence of lack of cell expansion. Progeny from a cross between hms-1 and the previously characterized PME inhibitor5 overexpression line suggest that HMS acts independently from other cell wall-modifying enzymes in the embryo. We propose that HMS is required for cell wall loosening in the embryo to facilitate cell expansion during the accumulation of storage reserves and that its role in the seed coat is masked by redundancy. © 2015 American Society of Plant Biologists. All Rights Reserved.

  4. Formation of Methyl Acrylate from CO 2 and Ethylene via Methylation of Nickelalactones

    KAUST Repository

    Bruckmeier, Christian; Lehenmeier, Maximilian W.; Reichardt, Robert; Vagin, Sergei; Rieger, Bernhard

    2010-01-01

    The nickel-induced coupling of ethylene and CO2 represents a promising pathway toward acrylates. To overcome the high bond dissociation energies of the M-O moieties, we worked out an in situ methylation of nickelalactones to realize the β

  5. THE KINETICS OF METHYL METHACRYLATE POLYMERIZATION INITIATED BY THE VOLATILE PRODUCTS OF A METHYL METHACRYLATE PLASMA

    Institute of Scientific and Technical Information of China (English)

    杨梅林; 马於光; 郑莹光; 沈家骢

    1990-01-01

    It is found that the volatile products of methyl methacrylate plasma can very actively initiate the polymerization of the monomer to produce ultrahigh molecular weight polymers. This polymerization of MMA occurs by a livlng free radical mechanism with instantaneous initiation and monomer transfer.

  6. Evidence for non-CpG methylation in mammals

    DEFF Research Database (Denmark)

    Yan, Jie; Zierath, Juleen R; Barres, Romain

    2011-01-01

    In mammals, the existence of cytosine methylation on non-CpG sequences is controversial. Here, we adapted a LuminoMetric-based Assay (LUMA) to determine global non-CpG methylation levels in rodent and human tissues. We observed that......In mammals, the existence of cytosine methylation on non-CpG sequences is controversial. Here, we adapted a LuminoMetric-based Assay (LUMA) to determine global non-CpG methylation levels in rodent and human tissues. We observed that...

  7. Abiotic Formation of Methyl Halides in the Terrestrial Environment

    Science.gov (United States)

    Keppler, F.

    2011-12-01

    Methyl chloride and methyl bromide are the most abundant chlorine and bromine containing organic compounds in the atmosphere. Since both compounds have relatively long tropospheric lifetimes they can effectively transport halogen atoms from the Earth's surface, where they are released, to the stratosphere and following photolytic oxidation form reactive halogen gases that lead to the chemical destruction of ozone. Methyl chloride and methyl bromide account for more than 20% of the ozone-depleting halogens delivered to the stratosphere and are predicted to grow in importance as the chlorine contribution to the stratosphere from anthropogenic CFCs decline. Today methyl chloride and methyl bromide originate mainly from natural sources with only a minor fraction considered to be of anthropogenic origin. However, until as recently as 2000 most of the methyl chloride and methyl bromide input to the atmosphere was considered to originate from the oceans, but investigations in recent years have clearly demonstrated that terrestrial sources such as biomass burning, wood-rotting fungi, coastal salt marshes, tropical vegetation and organic matter degradation must dominate the atmospheric budgets of these trace gases. However, many uncertainties still exist regarding strengths of both sources and sinks, as well as the mechanisms of formation of these naturally occurring halogenated gases. A better understanding of the atmospheric budget of both methyl chloride and methyl bromide is therefore required for reliable prediction of future ozone depletion. Biotic and abiotic methylation processes of chloride and bromide ion are considered to be the dominant pathways of formation of these methyl halides in nature. In this presentation I will focus on abiotic formation processes in the terrestrial environment and the potential parameters that control their emissions. Recent advances in our understanding of the abiotic formation pathway of methyl halides will be discussed. This will

  8. Resistance of sunflower hybrids to imazamox and tribenuron-methyl

    DEFF Research Database (Denmark)

    Bozic, D; Saric, M; Malidza, G

    2012-01-01

    The response of the imazamox resistant and susceptible sunflower hybrids Rimi and S to imazamox and of tribenuron-methyl resistant and susceptible hybrids Rsu and S to tribenuron-methyl was investigated both in a whole-plant bioassay and in field experiments. Plants were treated post-emergence wi......The response of the imazamox resistant and susceptible sunflower hybrids Rimi and S to imazamox and of tribenuron-methyl resistant and susceptible hybrids Rsu and S to tribenuron-methyl was investigated both in a whole-plant bioassay and in field experiments. Plants were treated post...

  9. Methylation pattern of IFNG in periapical granulomas and radicular cysts.

    Science.gov (United States)

    Campos, Kelma; Gomes, Carolina Cavaliéri; de Fátima Correia-Silva, Jeane; Farias, Lucyana Conceição; Fonseca-Silva, Thiago; Bernardes, Vanessa Fátima; Pereira, Cláudia Maria; Gomez, Ricardo Santiago

    2013-04-01

    Interferon-γ plays an important role in the pathogenesis of periapical lesions, and the methylation of IFNG has been associated with transcriptional inactivation. The purpose of the present study was to investigate IFNG promoter methylation in association with gene transcription and protein levels in periapical granulomas and radicular cysts. Methylation-specific polymerase chain reaction was used to assess the DNA methylation pattern of the IFNG gene in 16 periapical granulomas and 13 radicular cyst samples. The transcription levels of IFNG mRNA were verified by quantitative real-time polymerase chain reaction, and protein expression was evaluated by immunohistochemistry. All the periapical lesion samples exhibited partial or total methylation of the IFNG gene. In addition, an increased methylation profile was found in radicular cysts compared with periapical granulomas. Increased IFNG mRNA expression was observed in the partially methylated periapical lesion samples relative to the samples that were completely methylated. The present study provides the first evidence of the possible impact of IFNG methylation on IFNG transcription in periapical lesions. Copyright © 2013 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  10. CpG Island Methylator Phenotype in Primary Gastric Carcinoma

    OpenAIRE

    TOJO Masayuki:筆頭著者; KONISHI Kazuo; YANO Yuichiro; KATAGIRI Atsushi; NOZAWA Hisako; KUBOTA Yutaro; MURAMOTO Takashi; KONDA Kenichi; SHINMURA Kensuke; TAKIMOTO Masafumi; IMAWARI Michio; YOSHIDA Hitoshi

    2013-01-01

    Gastric cancers (GC) with methylation of multiple CpG islands have a CpG island methylator phenotype (CIMP) and they can have different biological features. The aim of this study was to investigate the DNA methylation status of GCs and its association with their clinicopathological features. We evaluated the methylation status of four genes (MINT1, MINT2, MINT25 and MINT31) in 105 primary GCs using bisulfite-pyrosequencing analysis. We classified tumors as CIMP-high (CIMP-H), CIMP-low (CIMP-L...

  11. Minimal methylation classifier (MIMIC): A novel method for derivation and rapid diagnostic detection of disease-associated DNA methylation signatures.

    Science.gov (United States)

    Schwalbe, E C; Hicks, D; Rafiee, G; Bashton, M; Gohlke, H; Enshaei, A; Potluri, S; Matthiesen, J; Mather, M; Taleongpong, P; Chaston, R; Silmon, A; Curtis, A; Lindsey, J C; Crosier, S; Smith, A J; Goschzik, T; Doz, F; Rutkowski, S; Lannering, B; Pietsch, T; Bailey, S; Williamson, D; Clifford, S C

    2017-10-18

    Rapid and reliable detection of disease-associated DNA methylation patterns has major potential to advance molecular diagnostics and underpin research investigations. We describe the development and validation of minimal methylation classifier (MIMIC), combining CpG signature design from genome-wide datasets, multiplex-PCR and detection by single-base extension and MALDI-TOF mass spectrometry, in a novel method to assess multi-locus DNA methylation profiles within routine clinically-applicable assays. We illustrate the application of MIMIC to successfully identify the methylation-dependent diagnostic molecular subgroups of medulloblastoma (the most common malignant childhood brain tumour), using scant/low-quality samples remaining from the most recently completed pan-European medulloblastoma clinical trial, refractory to analysis by conventional genome-wide DNA methylation analysis. Using this approach, we identify critical DNA methylation patterns from previously inaccessible cohorts, and reveal novel survival differences between the medulloblastoma disease subgroups with significant potential for clinical exploitation.

  12. Thermal Decomposition of Potential Ester Biofuels. Part I: Methyl Acetate and Methyl Butanoate

    Energy Technology Data Exchange (ETDEWEB)

    Porterfield, Jessica P.; Bross, David H.; Ruscic, Branko; Thorpe, James H.; Nguyen, Thanh Lam; Baraban, Joshua H.; Stanton, John F.; Daily, John W.; Ellison, G. Barney

    2017-06-09

    Two methyl esters have been examined as models for the pyrolysis of biofuels. Dilute samples (0.06 - 0.13%) of methyl acetate (CH3COOCH3) and methyl butanoate (CH3CH2CH2COOCH3) were entrained in (He, Ar) carrier gas and decomposed in a set of flash-pyrolysis micro-reactors. The pyrolysis products resulting from the methyl esters were detected and identified by vacuum ultraviolet photoionization mass spectrometry. Complementary product identification was provided by matrix infrared absorption spectroscopy. Pyrolysis pressures in the pulsed micro-reactor were roughly 20 Torr and residence times through the reactors were approximately 25 - 150 µs. Reactor temperatures of 300 – 1600 K were explored. Decomposition of CH3COOCH3 commences at 1000 K and the initial products are (CH2=C=O and CH3OH). As the micro-reactor is heated to 1300 K, a mixture of (CH2=C=O and CH3OH, CH3, CH2=O, H, CO, CO2) appears. The thermal cracking of CH3CH2CH2COOCH3 begins at 800 K with the formation of (CH3CH2CH=C=O, CH3OH). By 1300 K, the pyrolysis of methyl butanoate yields a complex mixture of (CH3CH2CH=C=O, CH3OH, CH3, CH2=O, CO, CO2, CH3CH=CH2, CH2CHCH2, CH2=C=CH2, HCCCH2, CH2=C=C=O, CH2=CH2, HCΞCH, CH2=C=O). Based on the results from the thermal cracking of methyl acetate and methyl butanoate, we predict several important decomposition channels for the pyrolysis of fatty acid methyl esters, R CH2-COOCH3. The lowest energy fragmentation will be a 4-center elimination of methanol to form the ketene, RCH=C=O. At higher temperatures, concerted

  13. Theoretical spectroscopic characterization at low temperatures of S-methyl thioformate and O-methyl thioformate

    International Nuclear Information System (INIS)

    Senent, M. L.; Puzzarini, C.; Hochlaf, M.; Domínguez-Gómez, R.; Carvajal, M.

    2014-01-01

    Highly correlated ab initio methods are employed to determine spectroscopic properties at low temperatures of two S-analogs of methyl formate: S-methyl thioformate CH 3 -S-CHO (MSCHO) and O-methyl thioformate CH 3 -O-CHS (MOCHS). Both species are detectable and they are expected to play an important role in Astrochemistry. Molecular properties are compared with those of the O-analog, methyl formate. Both isomers present two conformers cis and trans. cis-CH 3 -S-CHO represents the most stable structure lying 4372.2 cm −1 below cis-CH 3 -O-CHS. The energy difference between the cis and trans forms is drastically lower for MSCHO (1134 cm −1 ) than for MOCHS (1963.6 cm −1 ). Harmonic and anharmonic fundamentals and the corresponding intensities, as well as the rotational constants for the ground vibrational and first excited torsional states and the centrifugal distortions constants, are provided. Low torsional energy levels have been obtained by solving variationally a two dimensional Hamiltonian expressed in terms of the two torsional degrees of freedom. The corresponding 2D potential energy surfaces have been computed at the CCSD(T)/aug-cc-pVTZ level of theory. The methyl torsional barriers V 3 (cis) are determined to be 139.7 cm −1 (CH 3 -S-CHO) and 670.4 cm −1 (CH 3 -O-CHS). The A/E splitting of ground torsional state has been estimated to be 0.438 cm −1 for CH 3 -S-CHO and negligible for CH 3 -O-CHS

  14. Theoretical spectroscopic characterization at low temperatures of S-methyl thioformate and O-methyl thioformate

    Energy Technology Data Exchange (ETDEWEB)

    Senent, M. L., E-mail: senent@iem.cfmac.csic.es [Departamento de Química y Física Teóricas, Instituto de Estructura de la Materia, IEM-C.S.I.C., Serrano 121, Madrid 28006 (Spain); Puzzarini, C., E-mail: cristina.puzzarini@unibo.it [Dipartimento di Chimica G. Ciamician, Università di Bologna, Via F. Selmi 2, I-40126 Bologna (Italy); Hochlaf, M., E-mail: hochlaf@univ-mlv.fr [Laboratoire de Modélisation et Simulation Multi Echelle, Université Paris-Est, MSME UMR 8208 CNRS, 5 boulevard Descartes, 77454 Marne-la-Vallée (France); Domínguez-Gómez, R., E-mail: rosa.dominguez@upm.es [Departamento de Ingeniería Civil, Cátedra de Química, E.U.I.T. Obras Públicas, Universidad Politécnica de Madrid, Madrid (Spain); Carvajal, M., E-mail: miguel.carvajal@dfa.uhu.es [Departamento de Física Aplicada, Facultad de Ciencias Experimentales, Unidad Asociada IEM-CSIC-U.Huelva, Universidad de Huelva, 21071 Huelva (Spain)

    2014-09-14

    Highly correlated ab initio methods are employed to determine spectroscopic properties at low temperatures of two S-analogs of methyl formate: S-methyl thioformate CH{sub 3}-S-CHO (MSCHO) and O-methyl thioformate CH{sub 3}-O-CHS (MOCHS). Both species are detectable and they are expected to play an important role in Astrochemistry. Molecular properties are compared with those of the O-analog, methyl formate. Both isomers present two conformers cis and trans. cis-CH{sub 3}-S-CHO represents the most stable structure lying 4372.2 cm{sup −1} below cis-CH{sub 3}-O-CHS. The energy difference between the cis and trans forms is drastically lower for MSCHO (1134 cm{sup −1}) than for MOCHS (1963.6 cm{sup −1}). Harmonic and anharmonic fundamentals and the corresponding intensities, as well as the rotational constants for the ground vibrational and first excited torsional states and the centrifugal distortions constants, are provided. Low torsional energy levels have been obtained by solving variationally a two dimensional Hamiltonian expressed in terms of the two torsional degrees of freedom. The corresponding 2D potential energy surfaces have been computed at the CCSD(T)/aug-cc-pVTZ level of theory. The methyl torsional barriers V{sub 3}(cis) are determined to be 139.7 cm{sup −1} (CH{sub 3}-S-CHO) and 670.4 cm{sup −1} (CH{sub 3}-O-CHS). The A/E splitting of ground torsional state has been estimated to be 0.438 cm{sup −1} for CH{sub 3}-S-CHO and negligible for CH{sub 3}-O-CHS.

  15. Synthesis of 1-Methyl-3-oxo-7-oxabicyclo[2.2.1]hept-5-ene-2-carboxylic Acid Methyl Ester

    Directory of Open Access Journals (Sweden)

    Gil Valdo José da Silva

    2005-11-01

    Full Text Available A simple and efficient method for the preparation of 1-methyl-3-oxo-7- oxabicyclo[2.2.1]hept-5-en-2-carboxylic acid methyl ester (1 is described. The first step is a highly regioselective Diels-Alder reaction between 2-methylfuran and methyl-3-bromo- propiolate. A remarkably difficult ketal hydrolysis reaction was effected by treatment with HCl, a simple reagent that was shown to be more efficient, in this case, than commonly used more elaborate methods.

  16. Automated sequence- and stereo-specific assignment of methyl-labeled proteins by paramagnetic relaxation and methyl-methyl nuclear overhauser enhancement spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Venditti, Vincenzo; Fawzi, Nicolas L.; Clore, G. Marius, E-mail: mariusc@mail.nih.gov [National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Laboratory of Chemical Physics (United States)

    2011-11-15

    Methyl-transverse relaxation optimized spectroscopy is rapidly becoming the preferred NMR technique for probing structure and dynamics of very large proteins up to {approx}1 MDa in molecular size. Data interpretation, however, necessitates assignment of methyl groups which still presents a very challenging and time-consuming process. Here we demonstrate that, in combination with a known 3D structure, paramagnetic relaxation enhancement (PRE), induced by nitroxide spin-labels incorporated at only a few surface-exposed engineered cysteines, provides fast, straightforward and robust access to methyl group resonance assignments, including stereoassignments for the methyl groups of leucine and valine. Neither prior assignments, including backbone assignments, for the protein, nor experiments that transfer magnetization between methyl groups and the protein backbone, are required. PRE-derived assignments are refined by 4D methyl-methyl nuclear Overhauser enhancement data, eliminating ambiguities and errors that may arise due to the high sensitivity of PREs to the potential presence of sparsely-populated transient states.

  17. Drugging the methylome: DNA methylation and memory.

    Science.gov (United States)

    Kennedy, Andrew J; Sweatt, J David

    2016-01-01

    Over the past decade, since epigenetic mechanisms were first implicated in memory formation and synaptic plasticity, dynamic DNA methylation reactions have been identified as integral to long-term memory formation, maintenance, and recall. This review incorporates various new findings that DNA methylation mechanisms are important regulators of non-Hebbian plasticity mechanisms, suggesting that these epigenetic mechanisms are a fundamental link between synaptic plasticity and metaplasticity. Because the field of neuroepigenetics is so young and the biochemical tools necessary to probe gene-specific questions are just now being developed and used, this review also speculates about the direction and potential of therapeutics that target epigenetic mechanisms in the central nervous system and the unique pharmacokinetic and pharmacodynamic properties that epigenetic therapies may possess. Mapping the dynamics of the epigenome in response to experiential learning, even a single epigenetic mark in isolation, remains a significant technical and bioinformatic hurdle facing the field, but will be necessary to identify changes to the methylome that govern memory-associated gene expression and effectively drug the epigenome.

  18. Accelerated degradation of methyl iodide by agrochemicals.

    Science.gov (United States)

    Zheng, Wei; Papiernik, Sharon K; Guo, Mingxin; Yates, Scott R

    2003-01-29

    The fumigant methyl iodide (MeI, iodomethane) is considered a promising alternative to methyl bromide (MeBr) for soil-borne pest control in high-cash-value crops. However, the high vapor pressure of MeI results in emissions of a significant proportion of the applied mass into the ambient air, and this may lead to pollution of the environment. Integrating the application of certain agrochemicals with soil fumigation provides a novel approach to reduce excessive fumigant emissions. This study investigated the potential for several agrochemicals that are commonly used in farming operations, including fertilizers and nitrification inhibitors, to transform MeI in aqueous solution. The pseudo-first-order hydrolysis half-life (t(1/2)) of MeI was approximately 108 d, while the transformation of MeI in aqueous solutions containing selected agrochemicals was more rapid, with t(1/2) agrochemicals on the rate of MeI degradation in soil was also determined. Adsorption to soil apparently reduced the availability of some nitrification inhibitors in the soil aqueous phase and lowered the degradation rate in soil. In contrast, addition of the nitrification inhibitors thiourea and allylthiourea to soil significantly accelerated the degradation of MeI, possibly due to soil surface catalysis. The t(1/2) of MeI was 300 h).

  19. DNA Methylation and Methylation Polymorphism in Genetically Stable In vitro Regenerates of Jatropha curcas L. Using Methylation-Sensitive AFLP Markers.

    Science.gov (United States)

    Rathore, Mangal S; Jha, Bhavanath

    2016-03-01

    The present investigation aimed to evaluate the degree and pattern of DNA methylation using methylation-sensitive AFLP (MS-AFLP) markers in genetically stable in vitro regenerates of Jatropha curcas L.. The genetically stable in vitro regenerates were raised through direct organogenesis via enhanced axillary shoot bud proliferation (Protocol-1) and in vitro-derived leaf regeneration (Protocol-2). Ten selective combinations of MS-AFLP primers produced 462 and 477 MS-AFLP bands in Protocol-1 (P-1) and Protocol-2 (P-2) regenerates, respectively. In P-1 regenerates, 15.8-31.17 % DNA was found methylated with an average of 25.24 %. In P-2 regenerates, 15.93-32.7 % DNA was found methylated with an average of 24.11 %. Using MS-AFLP in P-1 and P-2 regenerates, 11.52-25.53 % and 13.33-25.47 % polymorphism in methylated DNA was reported, respectively. Compared to the mother plant, P-1 regenerates showed hyper-methylation while P-2 showed hypo-methylation. The results clearly indicated alternation in degree and pattern of DNA methylation; hence, epigenetic instability in the genetically stable in vitro regenerates of J. curcas, developed so far using two different regeneration systems and explants of two different origins. The homologous nucleotide fragments in genomes of P-1 and P-2 regenerates showing methylation re-patterning might be involved in immediate adaptive responses and developmental processes through differential regulation of transcriptome under in vitro conditions.

  20. MTHFR methylation moderates the impact of smoking on DNA methylation at AHRR for African American young adults.

    Science.gov (United States)

    Beach, Steven R H; Lei, Man Kit; Ong, Mei Ling; Brody, Gene H; Dogan, Meeshanthini V; Philibert, Robert A

    2017-09-01

    Smoking has been shown to have a large, reliable, and rapid effect on demethylation of AHRR, particularly at cg05575921, suggesting that methylation may be used as an index of cigarette consumption. Because the availability of methyl donors may also influence the degree of demethylation in response to smoking, factors that affect the activity of methylene tetrahydrofolate reductase (MTHFR), a key regulator of methyl group availability, may be of interest. In the current investigation, we examined the extent to which individual differences in methylation of MTHFR moderated the association between smoking and demethylation at cg05575921 as well as at other loci on AHRR associated with a main effect of smoking. Using a discovery sample (AIM, N = 293), and a confirmatory sample (SHAPE, N = 368) of young adult African Americans, degree of methylation of loci in the first exon of MTHFR was associated with amplification of the association between smoking and AHRR demethylation at cg05575921. However, genetic variation at a commonly studied MTHFR variant, C677T, did not influence cg05575921 methylation. The significant interaction between MTHFR methylation and the smoking-induced response at cg05575921 suggests a role for individual differences in methyl cycle regulation in understanding the effects of cigarette consumption on genome wide DNA methylation. © 2017 Wiley Periodicals, Inc.

  1. A DNA methylation microarray-based study identifies ERG as a gene commonly methylated in prostate cancer.

    Science.gov (United States)

    Schwartzman, Jacob; Mongoue-Tchokote, Solange; Gibbs, Angela; Gao, Lina; Corless, Christopher L; Jin, Jennifer; Zarour, Luai; Higano, Celestia; True, Lawrence D; Vessella, Robert L; Wilmot, Beth; Bottomly, Daniel; McWeeney, Shannon K; Bova, G Steven; Partin, Alan W; Mori, Motomi; Alumkal, Joshi

    2011-10-01

    DNA methylation of promoter regions is a common event in prostate cancer, one of the most common cancers in men worldwide. Because prior reports demonstrating that DNA methylation is important in prostate cancer studied a limited number of genes, we systematically quantified the DNA methylation status of 1505 CpG dinucleotides for 807 genes in 78 paraffin-embedded prostate cancer samples and three normal prostate samples. The ERG gene, commonly repressed in prostate cells in the absence of an oncogenic fusion to the TMPRSS2 gene, was one of the most commonly methylated genes, occurring in 74% of prostate cancer specimens. In an independent group of patient samples, we confirmed that ERG DNA methylation was common, occurring in 57% of specimens, and cancer-specific. The ERG promoter is marked by repressive chromatin marks mediated by polycomb proteins in both normal prostate cells and prostate cancer cells, which may explain ERG's predisposition to DNA methylation and the fact that tumors with ERG DNA methylation were more methylated, in general. These results demonstrate that bead arrays offer a high-throughput method to discover novel genes with promoter DNA methylation such as ERG, whose measurement may improve our ability to more accurately detect prostate cancer.

  2. Cytosine methylation at CpCpG sites triggers accumulation of non-CpG methylation in gene bodies

    OpenAIRE

    Zabet, NR; Catoni, Marco; Prischi, F; Paszkowski, Jerzy Waclaw

    2017-01-01

    Methylation of cytosine is an epigenetic mark involved in the regulation of transcription, usually associated with transcriptional repression. In mammals, methylated cytosines are found predominantly in CpGs but in plants non-CpG methylation (in the CpHpG or CpHpH contexts, where H is A, C or T) is also present and is associated with the transcriptional silencing of transposable elements. In addition, CpG methylation is found in coding regions of active genes. In the absence of the demethylas...

  3. Kismeth: Analyzer of plant methylation states through bisulfite sequencing

    Directory of Open Access Journals (Sweden)

    Martienssen Robert A

    2008-09-01

    Full Text Available Abstract Background There is great interest in probing the temporal and spatial patterns of cytosine methylation states in genomes of a variety of organisms. It is hoped that this will shed light on the biological roles of DNA methylation in the epigenetic control of gene expression. Bisulfite sequencing refers to the treatment of isolated DNA with sodium bisulfite to convert unmethylated cytosine to uracil, with PCR converting the uracil to thymidine followed by sequencing of the resultant DNA to detect DNA methylation. For the study of DNA methylation, plants provide an excellent model system, since they can tolerate major changes in their DNA methylation patterns and have long been studied for the effects of DNA methylation on transposons and epimutations. However, in contrast to the situation in animals, there aren't many tools that analyze bisulfite data in plants, which can exhibit methylation of cytosines in a variety of sequence contexts (CG, CHG, and CHH. Results Kismeth http://katahdin.mssm.edu/kismeth is a web-based tool for bisulfite sequencing analysis. Kismeth was designed to be used with plants, since it considers potential cytosine methylation in any sequence context (CG, CHG, and CHH. It provides a tool for the design of bisulfite primers as well as several tools for the analysis of the bisulfite sequencing results. Kismeth is not limited to data from plants, as it can be used with data from any species. Conclusion Kismeth simplifies bisulfite sequencing analysis. It is the only publicly available tool for the design of bisulfite primers for plants, and one of the few tools for the analysis of methylation patterns in plants. It facilitates analysis at both global and local scales, demonstrated in the examples cited in the text, allowing dissection of the genetic pathways involved in DNA methylation. Kismeth can also be used to study methylation states in different tissues and disease cells compared to a reference sequence.

  4. Oxidative stability and ignition quality of algae derived methyl esters containing varying levels of methyl eicosapentaenoate and methyl docosahexaenoate

    Science.gov (United States)

    Bucy, Harrison

    Microalgae is currently receiving strong consideration as a potential biofuel feedstock to help meet the advanced biofuels mandate of the 2007 Energy Independence and Security Act because of its theoretically high yield (gallons/acre/year) in comparison to current terrestrial feedstocks. Additionally, microalgae also do not compete with food and can be cultivated with wastewater on non-arable land. Microalgae lipids can be converted into a variety of biofuels including fatty acid methyl esters (e.g. FAME biodiesel), renewable diesel, renewable gasoline, or jet fuel. For microalgae derived FAME, the fuel properties will be directly related to the fatty acid composition of the lipids produced by the given microalgae strain. Several microalgae species under consideration for wide scale cultivation, such as Nannochloropsis, produce lipids with fatty acid compositions containing substantially higher quantities of long chainpolyunsaturated fatty acids (LC-PUFA) in comparison to terrestrial feedstocks. It is expected that increased levels of LC-PUFA will be problematic in terms of meeting all of the current ASTM specifications for biodiesel. For example, it is known that oxidative stability and cetane number decrease with increasing levels of LC-PUFA. However, these same LC-PUFA fatty acids, such as eicosapentaenoic acid (EPA: C20:5) and docosahexaenoic acid (DHA: C22:6) are known to have high nutritional value thereby making separation of these compounds economically attractive. Given the uncertainty in the future value of these LC-PUFA compounds and the economic viability of the separation process, the goal of this study was to examine the oxidative stability and ignition quality of algae-based FAME with varying levels of EPA and DHA removal. Oxidative stability tests were conducted at a temperature of 110°C and airflow of 10 L/h using a Metrohm 743 Rancimat with automatic induction period determination following the EN 14112 Method from the ASTM D6751 and EN 14214

  5. Monoclonal antibodies specific for the organophosphate pesticide azinphos-methyl

    NARCIS (Netherlands)

    Jones, WT; Harvey, D; Jones, SD; Ryan, GB; Wynberg, H; TenHoeve, W; Reynolds, PHS

    1995-01-01

    2-(2-Mercapto-5-methyl-1,3,2-dioxaphosphorinan-5-yl,2-sulphide) methoxyacetic acid has been synthesized and used to prepare an azinphos hapten and protein conjugates. Monoclonal antibodies of high affinity against the pesticide azinphos-methyl were prepared from mice immunized with the

  6. Infraspecific DNA methylation polymorphism in cotton (Gossypium hirsutum L.).

    Science.gov (United States)

    Keyte, Anna L; Percifield, Ryan; Liu, Bao; Wendel, Jonathan F

    2006-01-01

    Cytosine methylation is important in the epigenetic regulation of gene expression and development in plants and has been implicated in silencing duplicate genes after polyploid formation in several plant groups. Relatively little information exists, however, on levels and patterns of methylation polymorphism (MP) at homologous loci within species. Here we explored the levels and patterns of methylation-polymorphism diversity at CCGG sites within allotetraploid cotton, Gossypium hirsutum, using a methylation-sensitive amplified fragment length polymorphism screen and a selected set of 20 G. hirsutum accessions for which we have information on genetic polymorphism levels and relationships. Methylation and MP exist at high levels within G. hirsutum: of 150 HpaII/MspI sites surveyed, 48 were methylated at the inner cytosine (32%) and 32 of these were polymorphic (67%). Both these values are higher than comparable measures of genetic diversity using restriction fragment length polymorphisms. The high percentage of methylation-polymorphic sites and potential relationship to gene expression underscore the potential significance of MP within and among populations. We speculate that biased correlation of methylation-polymorphic sites and genes in cotton may be a consequence of polyploidy and the attendant doubling of all genes.

  7. 21 CFR 173.250 - Methyl alcohol residues.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Methyl alcohol residues. 173.250 Section 173.250 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD.... Methyl alcohol may be present in the following foods under the conditions specified: (a) In spice...

  8. Methyl chavicol: characterization of its biogenic emission rate

    NARCIS (Netherlands)

    Bouvier-Brown, N.C.; Goldstein, A.H.; Worton, D.R.; Matross, D.M.; Gilman, J.B.; Kuster, W.C.; Welsh-Bon, D.; Warneke, C.; de Gouw, J.A.; Cahill, M.J.; Holzinger, R.

    2009-01-01

    We report measurements of ambient atmospheric mixing ratios for methyl chavicol and determine its biogenic emission rate. Methyl chavicol, a biogenic oxygenated aromatic compound, is abundant within and above Blodgett Forest, a ponderosa pine forest in the Sierra Nevada Mountains of California.

  9. Effects of cytosine methylation on transcription factor binding sites

    KAUST Repository

    Medvedeva, Yulia A

    2014-03-26

    Background: DNA methylation in promoters is closely linked to downstream gene repression. However, whether DNA methylation is a cause or a consequence of gene repression remains an open question. If it is a cause, then DNA methylation may affect the affinity of transcription factors (TFs) for their binding sites (TFBSs). If it is a consequence, then gene repression caused by chromatin modification may be stabilized by DNA methylation. Until now, these two possibilities have been supported only by non-systematic evidence and they have not been tested on a wide range of TFs. An average promoter methylation is usually used in studies, whereas recent results suggested that methylation of individual cytosines can also be important.Results: We found that the methylation profiles of 16.6% of cytosines and the expression profiles of neighboring transcriptional start sites (TSSs) were significantly negatively correlated. We called the CpGs corresponding to such cytosines " traffic lights" We observed a strong selection against CpG " traffic lights" within TFBSs. The negative selection was stronger for transcriptional repressors as compared with transcriptional activators or multifunctional TFs as well as for core TFBS positions as compared with flanking TFBS positions.Conclusions: Our results indicate that direct and selective methylation of certain TFBS that prevents TF binding is restricted to special cases and cannot be considered as a general regulatory mechanism of transcription. 2013 Medvedeva et al.; licensee BioMed Central Ltd.

  10. Chemical oxygen demand (cod) attenuation of methyl red in water ...

    African Journals Online (AJOL)

    Chemical oxygen demand (cod) attenuation of methyl red in water using biocarbons obtained from Nipa palm leaves. ... eco-friendly and locally accessible biocarbon for mitigation of organic contaminants in water. Keywords: Chemical oxygen demand, biocarbon, methyl red, biodegradation, bioremediation, Nipa palm ...

  11. 7 CFR 305.6 - Methyl bromide fumigation treatment schedules.

    Science.gov (United States)

    2010-01-01

    ... 12 40 or above 16 8 T408-g-1 Chamber 60 or above 10 24 60 or above 20 15.5 T408-g-2 Tarpaulin 60 or..., fumigation with methyl bromide for sapote fruit fly. Regulated citrus fruits originating inside an area quarantined for sapote fruit fly that are to be moved outside the quarantined area may be treated with methyl...

  12. Alternative Production of Fatty Acid Methyl Esters from Triglycerides ...

    African Journals Online (AJOL)

    The catalysts activity was tested in thermocatalytic cracking of triglyceride; a direct conversion process for fatty acid methyl esters (biodiesel). The SZ1 not only exhibited higher conversion of triglycerides but higher fatty acid methyl esters (FAMEs) yields of approximately 59% after 3h as compared to SZ2 (32%). In addition ...

  13. Implications of DNA Methylation in Parkinson’s Disease

    Directory of Open Access Journals (Sweden)

    Ernesto Miranda-Morales

    2017-07-01

    Full Text Available It has been 200 years since Parkinson’s disease (PD was first described, yet many aspects of its etiopathogenesis remain unclear. PD is a progressive and complex neurodegenerative disorder caused by genetic and environmental factors including aging, nutrition, pesticides and exposure to heavy metals. DNA methylation may be altered in response to some of these factors; therefore, it is proposed that epigenetic mechanisms, particularly DNA methylation, can have a fundamental role in gene–environment interactions that are related with PD. Epigenetic changes in PD-associated genes are now widely studied in different populations, to discover the mechanisms that contribute to disease development and identify novel biomarkers for early diagnosis and future pharmacological treatment. While initial studies sought to find associations between promoter DNA methylation and the regulation of associated genes in PD brain tissue, more recent studies have described concordant DNA methylation patterns between blood and brain tissue DNA. These data justify the use of peripheral blood samples instead of brain tissue for epigenetic studies. Here, we summarize the current data about DNA methylation changes in PD and discuss the potential of DNA methylation as a potential biomarker for PD. Additionally, we discuss environmental and nutritional factors that have been implicated in DNA methylation. Although the search for significant DNA methylation changes and gene expression analyses of PD-associated genes have yielded inconsistent and contradictory results, epigenetic modifications remain under investigation for their potential to reveal the link between environmental risk factors and the development of PD.

  14. DNA methylation and genetic diversity analysis of genus Cycas in ...

    African Journals Online (AJOL)

    10 Cycas species as well as one subspecies localized in Thailand were studied using the methylation sensitive amplification polymorphism (MSAP) technique. 11 MSAP primer combinations were used and 720 MSAP bands were generated. The percentages of DNA methylation estimated from MSAP fingerprints were in ...

  15. Heterogeneity of DNA methylation in multifocal prostate cancer.

    Science.gov (United States)

    Serenaite, Inga; Daniunaite, Kristina; Jankevicius, Feliksas; Laurinavicius, Arvydas; Petroska, Donatas; Lazutka, Juozas R; Jarmalaite, Sonata

    2015-01-01

    Most prostate cancer (PCa) cases are multifocal, and separate foci display histological and molecular heterogeneity. DNA hypermethylation is a frequent alteration in PCa, but interfocal heterogeneity of these changes has not been extensively investigated. Ten pairs of foci from multifocal PCa and 15 benign prostatic hyperplasia (BPH) samples were obtained from prostatectomy specimens, resulting altogether in 35 samples. Methylation-specific PCR (MSP) was used to evaluate methylation status of nine tumor suppressor genes (TSGs), and a set of selected TSGs was quantitatively analyzed for methylation intensity by pyrosequencing. Promoter sequences of the RASSF1 and ESR1 genes were methylated in all paired PCa foci, and frequent (≥75 %) DNA methylation was detected in RARB, GSTP1, and ABCB1 genes. MSP revealed different methylation status of at least one gene in separate foci in 8 out of 10 multifocal tumors. The mean methylation level of ESR1, GSTP1, RASSF1, and RARB differed between the paired foci of all PCa cases. The intensity of DNA methylation in these TSGs was significantly higher in PCa cases than in BPH (p epigenetic profile of recurrent tumors can be inferred from our data.

  16. Production of methyl-vinyl ketone from levulinic acid

    Energy Technology Data Exchange (ETDEWEB)

    Dumesic, James A [Verona, WI; West,; Ryan, M [Madison, WI

    2011-06-14

    A method for converting levulinic acid to methyl vinyl ketone is described. The method includes the steps of reacting an aqueous solution of levulinic acid, over an acid catalyst, at a temperature of from room temperature to about 1100 K. Methyl vinyl ketone is thereby formed.

  17. Synthesis of methyl propanoate by Baeyer-Villiger monooxygenases

    NARCIS (Netherlands)

    van Beek, Hugo L.; Winter, Remko T.; Eastham, Graham R.; Fraaije, Marco W.

    2014-01-01

    Methyl propanoate is an important precursor for polymethyl methacrylates. The use of a Baeyer-Villiger monooxygenase (BVMO) to produce this compound was investigated. Several BVMOs were identified that produce the chemically non-preferred product methyl propanoate in addition to the normal product

  18. Novel methyl transfer during chemotaxis in Bacillus subtilis

    International Nuclear Information System (INIS)

    Thoelke, M.S.; Kirby, J.R.; Ordal, G.W.

    1989-01-01

    If Bacillus subtilis is incubated in radioactive methionine in the absence of protein synthesis, the methyl-accepting chemotaxis proteins (MCPs) become radioactively methylated. If the bacteria are further incubated in excess nonradioactive methionine (cold-chased) and then given the attractant aspartate, the MCPs lose about half of their radioactivity due to turnover, in which lower specific activity methyl groups from S-adenosylmethionine (AdoMet) replace higher specific activity ones. Due to the cold-chase, the specific activity of the AdoMet pool is reduced at least 2-fold. If, later, the attractant is removed, higher specific activity methyl groups return to the MCPs. Thus, there must exist an unidentified methyl carrier than can reversibly receive methyl groups from the MCPs. In a similar experiment, labeled cells were transferred to a flow cell and exposed to addition and removal of attractant and of repellent. All four kinds of stimuli were found to cause methanol production. Bacterial with maximally labeled MCPs were exposed to many cycles of addition and removal of attractant; the maximum amount of radioactive methanol was evolved on the third, not the first, cycle. This result suggests that there is a precursor-product relationship between methyl groups on the MCPs and on the unidentified carrier, which might be the direct source of methanol. However, since no methanol was produced when a methyltransferase mutant, whose MCPs were unmethylated, was exposed to addition and removal of attractant or repellent, the methanol must ultimately derive from methylated MCPs

  19. Comparison of Different Promoter Methylation Assays in Breast Cancer

    Directory of Open Access Journals (Sweden)

    Karijn P. M. Suijkerbuijk

    2010-01-01

    Full Text Available Background: Promoter hypermethylation has emerged as a promising cancer biomarker. Currently, a large variety of quantitative and non-quantitative techniques is used to measure methylation in clinical specimens. Here we directly compared three commonly used methylation assays and assessed the influence of tissue fixation, target sequence location and the amount of DNA on their performance.

  20. Polymerization of methyl methacrylate by diphenylamido bis (methylcyclopentadienyl) ytterbium complex

    Institute of Scientific and Technical Information of China (English)

    WANG, Yao-Rong(王耀荣); SHEN, Qi(沈琪); MA, Jia-Le(马家乐); ZHAO, Qun(赵群)

    2000-01-01

    Methyl methacrylate (MMA) was effectively polymerized by diphenylamido bis(methyicyclopentadienyl) ytterbium complex (MeCp)2YbNPh2(THF). Tne reaction can be carried out over a range of polymerization temperature from - 40℃ to 40℃ and gives the polyMMA with high molecular weights.The initiation mechanism was demonstrated by diphenylamidoterminated methyl methacrylate oligomer.

  1. Acute exercise remodels promoter methylation in human skeletal muscle

    DEFF Research Database (Denmark)

    Barrès, Romain; Yan, Jie; Egan, Brendan

    2012-01-01

    DNA methylation is a covalent biochemical modification controlling chromatin structure and gene expression. Exercise elicits gene expression changes that trigger structural and metabolic adaptations in skeletal muscle. We determined whether DNA methylation plays a role in exercise-induced gene ex...

  2. Folate, colorectal cancer and the involvement of DNA methylation.

    Science.gov (United States)

    Williams, Elizabeth A

    2012-11-01

    Diet is a major factor in the aetiology of colorectal cancer (CRC). Epidemiological evidence suggests that folate confers a modest protection against CRC risk. However, the relationship is complex, and evidence from human intervention trials and animal studies suggests that a high-dose of folic acid supplementation may enhance the risk of colorectal carcinogenesis in certain circumstances. The molecular mechanisms underlying the apparent dual modulatory effect of folate on colorectal carcinogenesis are not fully understood. Folate is central to C1 metabolism and is needed for both DNA synthesis and DNA methylation, providing plausible biological mechanisms through which folate could modulate cancer risk. Aberrant DNA methylation is an early event in colorectal carcinogenesis and is typically associated with the transcriptional silencing of tumour suppressor genes. Folate is required for the production of S-adenosyl methionine, which serves as a methyl donor for DNA methylation events; thereby folate availability is proposed to modulate DNA methylation status. The evidence for an effect of folate on DNA methylation in the human colon is limited, but a modulation of DNA methylation in response to folate has been demonstrated. More research is required to clarify the optimum intake of folate for CRC prevention and to elucidate the effect of folate availability on DNA methylation and the associated impact on CRC biology.

  3. Biological meaning of the methyl eugenol to fruit flies

    Energy Technology Data Exchange (ETDEWEB)

    Tachi, S.; Subahar, S

    1998-12-16

    The objective of this research is to test a hypothesis whether methyl eugenol has a benefit in sexual selection of fruit flies and to find at what age the male flies respond to methyl eugenol. This test was conducted using carambola fruit fly (Bractocera carambolae) at Inter University Center for Life Science of ITB. The results of the tests are summarized as follows ; 1. Males started to respond to methyl eugenol at the age of 11 days old and the maximum number of males were recorded on 14 and 15 days old. 2. Most of the carambola fruit fly start to respond to methyl eugenol before they become sexually mature. 3. A very small percentage of newly emerged males (less than 1%) survive to mate with females during treatment with methyl eugenol. Methyl eugenol has benefit in sexual selection of carabola fruit fly, i.e., males responded to methyl eugenol before they engage in sexual activities, while females responded to methyl eugenol only when males started their mating activities. (author)

  4. Acibenzolar-S-methyl induces lettuce resistance against ...

    African Journals Online (AJOL)

    Jane

    2011-08-24

    Aug 24, 2011 ... Acibenzolar-S-methyl (Benzo [1,2,3] thiadiazole-7-carbothioic acid-S-methyl ester, ASM; Bion 50 WG) was found to ... compounds are frequently used, they have hazardous effect on ... resistance (SAR) is characterized by a reduction in the number of ... cellular defence responses such as synthesis of patho-.

  5. FIXED-BED COLUMN ADSORPTION OF METHYL BLUE USING ...

    African Journals Online (AJOL)

    userpc

    Axle Wood Carbon (AWC) was used to study the removal of Methyl Blue (MB) from ... height, initial methyl blue (MB) concentration, .... colour from blue to dark purple- .... Environ. Earth Sci. 13; 1–13. Yagub, M. T., Sen, T. K., Afroze, S., and Ang,.

  6. DNMT1-interacting RNAs block gene specific DNA methylation

    Science.gov (United States)

    Di Ruscio, Annalisa; Ebralidze, Alexander K.; Benoukraf, Touati; Amabile, Giovanni; Goff, Loyal A.; Terragni, Joylon; Figueroa, Maria Eugenia; De Figureido Pontes, Lorena Lobo; Alberich-Jorda, Meritxell; Zhang, Pu; Wu, Mengchu; D’Alò, Francesco; Melnick, Ari; Leone, Giuseppe; Ebralidze, Konstantin K.; Pradhan, Sriharsa; Rinn, John L.; Tenen, Daniel G.

    2013-01-01

    Summary DNA methylation was described almost a century ago. However, the rules governing its establishment and maintenance remain elusive. Here, we present data demonstrating that active transcription regulates levels of genomic methylation. We identified a novel RNA arising from the CEBPA gene locus critical in regulating the local DNA methylation profile. This RNA binds to DNMT1 and prevents CEBPA gene locus methylation. Deep sequencing of transcripts associated with DNMT1 combined with genome-scale methylation and expression profiling extended the generality of this finding to numerous gene loci. Collectively, these results delineate the nature of DNMT1-RNA interactions and suggest strategies for gene selective demethylation of therapeutic targets in disease. PMID:24107992

  7. DNA methylation dynamics in muscle development and disease

    Directory of Open Access Journals (Sweden)

    Elvira eCarrio

    2015-03-01

    Full Text Available DNA methylation is an essential epigenetic modification for mammalian development and is crucial for the establishment and maintenance of cellular identity. Traditionally, DNA methylation has been considered as a permanent repressive epigenetic mark. However, the application of genome-wide approaches has allowed the analysis of DNA methylation in different genomic contexts revealing a more dynamic regulation than originally thought, since active DNA methylation and demethylation occur during cellular differentiation and tissue specification. Satellite cells are the primary stem cells in adult skeletal muscle and are responsible for postnatal muscle growth, hypertrophy, and muscle regeneration. This review outlines the published data regarding DNA methylation changes along the skeletal muscle program, in both physiological and pathological conditions, to better understand the epigenetic mechanisms that control myogenesis

  8. DNA methylation regulates neurophysiological spatial representation in memory formation

    Directory of Open Access Journals (Sweden)

    Eric D. Roth

    2015-04-01

    Full Text Available Epigenetic mechanisms including altered DNA methylation are critical for altered gene transcription subserving synaptic plasticity and the retention of learned behavior. Here, we tested the idea that one role for activity-dependent altered DNA methylation is stabilization of cognition-associated hippocampal place cell firing in response to novel place learning. We observed that a behavioral protocol (spatial exploration of a novel environment known to induce hippocampal place cell remapping resulted in alterations of hippocampal Bdnf DNA methylation. Further studies using neurophysiological in vivo single-unit recordings revealed that pharmacological manipulations of DNA methylation decreased long-term but not short-term place field stability. Together, our data highlight a role for DNA methylation in regulating neurophysiological spatial representation and memory formation.

  9. [Neuroepigenetics: Desoxyribonucleic acid methylation in Alzheimer's disease and other dementias].

    Science.gov (United States)

    Mendioroz Iriarte, Maite; Pulido Fontes, Laura; Méndez-López, Iván

    2015-05-21

    DNA methylation is an epigenetic mechanism that controls gene expression. In Alzheimer's disease (AD), global DNA hypomethylation of neurons has been described in the human cerebral cortex. Moreover, several variants in the methylation pattern of candidate genes have been identified in brain tissue when comparing AD patients and controls. Specifically, DNA methylation changes have been observed in PSEN1 and APOE, both genes previously being involved in the pathophysiology of AD. In other degenerative dementias, methylation variants have also been described in key genes, such as hypomethylation of the SNCA gene in Parkinson's disease and dementia with Lewy bodies or hypermethylation of the GRN gene promoter in frontotemporal dementia. The finding of aberrant DNA methylation patterns shared by brain tissue and peripheral blood opens the door to use those variants as epigenetic biomarkers in the diagnosis of neurodegenerative diseases. Copyright © 2014 Elsevier España, S.L.U. All rights reserved.

  10. DNA methylation regulates neurophysiological spatial representation in memory formation.

    Science.gov (United States)

    Roth, Eric D; Roth, Tania L; Money, Kelli M; SenGupta, Sonda; Eason, Dawn E; Sweatt, J David

    2015-04-01

    Epigenetic mechanisms including altered DNA methylation are critical for altered gene transcription subserving synaptic plasticity and the retention of learned behavior. Here we tested the idea that one role for activity-dependent altered DNA methylation is stabilization of cognition-associated hippocampal place cell firing in response to novel place learning. We observed that a behavioral protocol (spatial exploration of a novel environment) known to induce hippocampal place cell remapping resulted in alterations of hippocampal Bdnf DNA methylation. Further studies using neurophysiological in vivo single unit recordings revealed that pharmacological manipulations of DNA methylation decreased long-term but not short-term place field stability. Together our data highlight a role for DNA methylation in regulating neurophysiological spatial representation and memory formation.

  11. Environmentally friendly properties of vegetable oil methyl esters

    Directory of Open Access Journals (Sweden)

    Gateau Paul

    2005-07-01

    Full Text Available Measurements were carried out on Vegetable Oil Methyl Esters (VOME or FAME answering the most recent specifications. The products tested are RME (Rapeseed oil Methyl Ester, ERME (Erucic Rapeseed oil Methyl Esters, SME (Sunflower oil Methyl Esters, and HOSME (High Oleic Sunflower oil Methyl Esters. They contain more than 99.5% of fatty acid mono esters. The compositions are given. VOME are not volatile and they are not easily flammable. They are not soluble in water and they are biodegradable. According to the methods implemented for the determination of the German classification of substances hazardous to waters WGK, they are not toxic on mammals and unlike diesel fuel they are not toxic on fish, daphnia, algae and bacteria. The RME is not either toxic for shrimps. According to tests on rabbits, RME and SME are not irritating for the skin and the eyes. VOME display particularly attractive environmental properties.

  12. Forensic DNA methylation profiling from evidence material for investigative leads

    Science.gov (United States)

    Lee, Hwan Young; Lee, Soong Deok; Shin, Kyoung-Jin

    2016-01-01

    DNA methylation is emerging as an attractive marker providing investigative leads to solve crimes in forensic genetics. The identification of body fluids that utilizes tissue-specific DNA methylation can contribute to solving crimes by predicting activity related to the evidence material. The age estimation based on DNA methylation is expected to reduce the number of potential suspects, when the DNA profile from the evidence does not match with any known person, including those stored in the forensic database. Moreover, the variation in DNA implicates environmental exposure, such as cigarette smoking and alcohol consumption, thereby suggesting the possibility to be used as a marker for predicting the lifestyle of potential suspect. In this review, we describe recent advances in our understanding of DNA methylation variations and the utility of DNA methylation as a forensic marker for advanced investigative leads from evidence materials. [BMB Reports 2016; 49(7): 359-369] PMID:27099236

  13. 4-Methyl-N-(2-methylbenzoylbenzenesulfonamide

    Directory of Open Access Journals (Sweden)

    B. Thimme Gowda

    2010-06-01

    Full Text Available In the title compound, C15H15NO3S, the conformation of the N—H bond in the C—SO2—NH—C(O segment is anti to the C=O bond. Further, the conformation of the C=O bond is syn to the ortho-methyl group in the benzoyl ring. The dihedral angle between the sulfonyl benzene ring and the —SO2—NH—C—O segment is 87.1 (1° and that between the sulfonyl and the benzoyl benzene rings is 58.2 (1°. In the crystal structure, molecules are linked by pairs of N—H...O(S hydrogen bonds, forming inversion dimers.

  14. Epigenetic regulation during fetal femur development: DNA methylation matters.

    Directory of Open Access Journals (Sweden)

    María C de Andrés

    Full Text Available Epigenetic modifications are heritable changes in gene expression without changes in DNA sequence. DNA methylation has been implicated in the control of several cellular processes including differentiation, gene regulation, development, genomic imprinting and X-chromosome inactivation. Methylated cytosine residues at CpG dinucleotides are commonly associated with gene repression; conversely, strategic loss of methylation during development could lead to activation of lineage-specific genes. Evidence is emerging that bone development and growth are programmed; although, interestingly, bone is constantly remodelled throughout life. Using human embryonic stem cells, human fetal bone cells (HFBCs, adult chondrocytes and STRO-1(+ marrow stromal cells from human bone marrow, we have examined a spectrum of developmental stages of femur development and the role of DNA methylation therein. Using pyrosequencing methodology we analysed the status of methylation of genes implicated in bone biology; furthermore, we correlated these methylation levels with gene expression levels using qRT-PCR and protein distribution during fetal development evaluated using immunohistochemistry. We found that during fetal femur development DNA methylation inversely correlates with expression of genes including iNOS (NOS2 and COL9A1, but not catabolic genes including MMP13 and IL1B. Furthermore, significant demethylation was evident in the osteocalcin promoter between the fetal and adult developmental stages. Increased TET1 expression and decreased expression of DNA (cytosine-5--methyltransferase 1 (DNMT1 in adult chondrocytes compared to HFBCs could contribute to the loss of methylation observed during fetal development. HFBC multipotency confirms these cells to be an ideal developmental system for investigation of DNA methylation regulation. In conclusion, these findings demonstrate the role of epigenetic regulation, specifically DNA methylation, in bone development

  15. Analysis of DNA methylation in various swine tissues.

    Directory of Open Access Journals (Sweden)

    Chun Yang

    Full Text Available DNA methylation is known to play an important role in regulating gene expression during biological development and tissue differentiation in eukaryotes. In this study, we used the fluorescence-labeled methylation-sensitive amplified polymorphism (F-MSAP method to assess the extent and pattern of cytosine methylation in muscle, heart, liver, spleen, lung, kidney and stomach from the swine strain Laiwu, and we also examined specific methylation patterns in the seven tissues. In total, 96,371 fragments, each representing a recognition site cleaved by either or both EcoRI + HpaII and EcoRI + MspI, the HpaII and MspI are isoschizomeric enzymes, were amplified using 16 pairs of selective primers. A total of 50,094 sites were found to be methylated at cytosines in seven tissues. The incidence of DNA methylation was approximately 53.99% in muscle, 51.24% in the heart, 50.18% in the liver, 53.31% in the spleen, 51.97% in the lung, 51.15% in the kidney and 53.39% in the stomach, as revealed by the incidence of differential digestion. Additionally, differences in DNA methylation levels imply that such variations may be related to specific gene expression during tissue differentiation, growth and development. Three types of bands were generated in the F-MSAP profile, the total numbers of these three types of bands in the seven tissues were 46,277, 24,801 and 25,293, respectively.In addition, different methylation patterns were observed in seven tissues from pig, and almost all of the methylation patterns detected by F-MSAP could be confirmed by Southern analysis using the isolated amplified fragments as probes. The results clearly demonstrated that the F-MSAP technique can be adapted for use in large-scale DNA methylation detection in the pig genome.

  16. Mercury methylation and bacterial activity associated to tropical phytoplankton

    International Nuclear Information System (INIS)

    Coelho-Souza, Sergio A.; Guimaraes, Jean R.D.; Mauro, Jane B.N.; Miranda, Marcio R.; Azevedo, Sandra M.F.O.

    2006-01-01

    The methylated form of mercury (Hg), methylmercury (MeHg), is one of the most toxic pollutants. Biotic and/or abiotic methylation, often associated to sulfate-reducing bacteria metabolism, occurs in aquatic environments and in many tropical areas, mostly in the periphyton associated to floating macrophyte roots. Data about mercury methylation by phytoplankton are scarce and the aim of this study was to verify the biotic influence in the methylation process in Microcystis aeruginosa and Sineccocystis sp. laboratory strains and in natural populations of phytoplankton from two different aquatic systems, the mesotrophic Ribeirao das Lajes reservoir and hypereutrophic oligohaline Jacarepagua lagoon, Rio de Janeiro state, Brazil. Adapted radiochemical techniques were used to measure sulfate-reduction, mercury methylation and bacterial activity in phytoplankton samples. Methyl- 203 Hg formation from added inorganic 203 Hg and 3 H-Leucine uptake were measured by liquid scintillation as well as sulfate-reduction, estimated as H 2 35 S produced from added Na 2 35 SO 4 . There was no significant difference in low methylation potentials (0.37%) among the two cyanobacterium species studied in laboratory conditions. At Ribeirao das Lajes reservoir, there was no significant difference in methylation, bacterial activity and sulfate-reduction of surface sediment between the sampling points. Methylation in sediments (3-4%) was higher than in phytoplankton (1.5%), the opposite being true for bacterial activity (sediment mean 6.6 against 150.3 nmol gdw -1 h -1 for phytoplankton samples). At Jacarepagua lagoon, an expressive bacterial activity (477.1 x 10 3 nmol gdw -1 h -1 at a concentration of 1000 nM leucine) and sulfate-reduction (∼21% H 2 35 S trapped) associated to phytoplankton (mostly cyanobacteria M. aeruginosa) was observed, but mercury methylation was not detected

  17. Mercury methylation and bacterial activity associated to tropical phytoplankton

    Energy Technology Data Exchange (ETDEWEB)

    Coelho-Souza, Sergio A. [Laboratorio de Tracadores Wolfgang Pfeiffer, SL 62, Instituto de Biofisica Carlos Chagas Filho, Bloco G, Ilha do Fundao, Universidade Federal do Rio de Janeiro (IBCCF/UFRJ), RJ, CEP 21949-900 (Brazil); Guimaraes, Jean R.D. [Laboratorio de Tracadores Wolfgang Pfeiffer, SL 62, Instituto de Biofisica Carlos Chagas Filho, Bloco G, Ilha do Fundao, Universidade Federal do Rio de Janeiro (IBCCF/UFRJ), RJ, CEP 21949-900 (Brazil)]. E-mail: jeanrdg@biof.ufrj.br; Mauro, Jane B.N. [Laboratorio de Tracadores Wolfgang Pfeiffer, SL 62, Instituto de Biofisica Carlos Chagas Filho, Bloco G, Ilha do Fundao, Universidade Federal do Rio de Janeiro (IBCCF/UFRJ), RJ, CEP 21949-900 (Brazil); Miranda, Marcio R. [Laboratorio de Tracadores Wolfgang Pfeiffer, SL 62, Instituto de Biofisica Carlos Chagas Filho, Bloco G, Ilha do Fundao, Universidade Federal do Rio de Janeiro (IBCCF/UFRJ), RJ, CEP 21949-900 (Brazil); Azevedo, Sandra M.F.O. [Laboratorio de Ecofisiologia e Toxicologia de Cianobacterias, IBCCF/UFRJ, RJ (Brazil)

    2006-07-01

    The methylated form of mercury (Hg), methylmercury (MeHg), is one of the most toxic pollutants. Biotic and/or abiotic methylation, often associated to sulfate-reducing bacteria metabolism, occurs in aquatic environments and in many tropical areas, mostly in the periphyton associated to floating macrophyte roots. Data about mercury methylation by phytoplankton are scarce and the aim of this study was to verify the biotic influence in the methylation process in Microcystis aeruginosa and Sineccocystis sp. laboratory strains and in natural populations of phytoplankton from two different aquatic systems, the mesotrophic Ribeirao das Lajes reservoir and hypereutrophic oligohaline Jacarepagua lagoon, Rio de Janeiro state, Brazil. Adapted radiochemical techniques were used to measure sulfate-reduction, mercury methylation and bacterial activity in phytoplankton samples. Methyl-{sup 203}Hg formation from added inorganic {sup 203}Hg and {sup 3}H-Leucine uptake were measured by liquid scintillation as well as sulfate-reduction, estimated as H{sub 2} {sup 35}S produced from added Na{sub 2} {sup 35}SO{sub 4}. There was no significant difference in low methylation potentials (0.37%) among the two cyanobacterium species studied in laboratory conditions. At Ribeirao das Lajes reservoir, there was no significant difference in methylation, bacterial activity and sulfate-reduction of surface sediment between the sampling points. Methylation in sediments (3-4%) was higher than in phytoplankton (1.5%), the opposite being true for bacterial activity (sediment mean 6.6 against 150.3 nmol gdw{sup -1} h{sup -1} for phytoplankton samples). At Jacarepagua lagoon, an expressive bacterial activity (477.1 x 10{sup 3} nmol gdw{sup -1} h{sup -1} at a concentration of 1000 nM leucine) and sulfate-reduction ({approx}21% H{sub 2} {sup 35}S trapped) associated to phytoplankton (mostly cyanobacteria M. aeruginosa) was observed, but mercury methylation was not detected.

  18. Community transmission of type 2 poliovirus after cessation of trivalent oral polio vaccine in Bangladesh: an open-label cluster-randomised trial and modelling study.

    Science.gov (United States)

    Taniuchi, Mami; Famulare, Michael; Zaman, Khalequ; Uddin, Md Jashim; Upfill-Brown, Alexander M; Ahmed, Tahmina; Saha, Parimalendu; Haque, Rashidul; Bandyopadhyay, Ananda S; Modlin, John F; Platts-Mills, James A; Houpt, Eric R; Yunus, Mohammed; Petri, William A

    2017-10-01

    Trivalent oral polio vaccine (tOPV) was replaced worldwide from April, 2016, by bivalent types 1 and 3 oral polio vaccine (bOPV) and one dose of inactivated polio vaccine (IPV) where available. The risk of transmission of type 2 poliovirus or Sabin 2 virus on re-introduction or resurgence of type 2 poliovirus after this switch is not understood completely. We aimed to assess the risk of Sabin 2 transmission after a polio vaccination campaign with a monovalent type 2 oral polio vaccine (mOPV2). We did an open-label cluster-randomised trial in villages in the Matlab region of Bangladesh. We randomly allocated villages (clusters) to either: tOPV at age 6 weeks, 10 weeks, and 14 weeks; or bOPV at age 6 weeks, 10 weeks, and 14 weeks and either one dose of IPV at age 14 weeks or two doses of IPV at age 14 weeks and 18 weeks. After completion of enrolment, we implemented an mOPV2 vaccination campaign that targeted 40% of children younger than 5 years, regardless of enrolment status. The primary outcome was Sabin 2 incidence in the 10 weeks after the campaign in per-protocol infants who did not receive mOPV2, as assessed by faecal shedding of Sabin 2 by reverse transcriptase quantitative PCR (RT-qPCR). The effect of previous immunity on incidence was also investigated with a dynamical model of poliovirus transmission to observe prevalence and incidence of Sabin 2 virus. This trial is registered at ClinicalTrials.gov, number NCT02477046. Between April 30, 2015, and Jan 14, 2016, individuals from 67 villages were enrolled to the study. 22 villages (300 infants) were randomly assigned tOPV, 23 villages (310 infants) were allocated bOPV and one dose of IPV, and 22 villages (329 infants) were assigned bOPV and two doses of IPV. Faecal shedding of Sabin 2 in infants who did not receive the mOPV2 challenge did not differ between children immunised with bOPV and one or two doses of IPV and those who received tOPV (15 of 252 [6%] vs six of 122 [4%]; odds ratio [OR] 1·29, 95% CI 0

  19. What a difference a 5f element makes: trivalent and tetravalent uranium halide complexes supported by one and two bis[2-(diisopropylphosphino)-4-methylphenyl]amido (PNP) ligands.

    Science.gov (United States)

    Cantat, Thibault; Scott, Brian L; Morris, David E; Kiplinger, Jaqueline L

    2009-03-02

    The coordination behavior of the bis[2-(diisopropylphosphino)-4-methylphenyl]amido ligand (PNP) toward UI3(THF)4 and UCl4 has been investigated to access new uranium(III) and uranium(IV) halide complexes supported by one and two PNP ligands. The reaction between (PNP)K (6) and 1 equiv of UI3(THF)4 afforded the trivalent halide complex (PNP)UI2(4-tBu-pyridine)2 (7) in the presence of 4-tert-butylpyridine. The same reaction carried out with UCl4 and no donor ligand gave [(PNP)UCl3]2 (8), in which the uranium coordination sphere in the (PNP)UCl3 unit is completed by a bridging chloride ligand. When UCl4 is reacted with 1 equiv (PNP)K (6) in the presence of THF, trimethylphosphine oxide (TMPO), or triphenylphosphineoxide (TPPO), the tetravalent halide complexes (PNP)UCl3(THF) (9), (PNP)UCl3(TMPO)2 (10), and (PNP)UCl3(TPPO) (11), respectively, are formed in excellent yields. The bis(PNP) complexes of uranium(III), (PNP)2UI (12), and uranium(IV), (PNP)2UCl2 (13), were easily isolated from the analogous reactions between 2 equiv of 6 and UI3(THF)4 or UCl4, respectively. Complexes 12 and 13 represent the first examples of complexes featuring two PNP ligands coordinated to a single metal center. Complexes 7-13 have been characterized by single-crystal X-ray diffraction and 1H and 31P NMR spectroscopy. The X-ray structures demonstrate the ability of the PNP ligand to adopt new coordination modes upon coordination to uranium. The PNP ligand can adopt both pseudo-meridional and pseudo-facial geometries when it is kappa3-(P,N,P) coordinated, depending on the steric demand at the uranium metal center. Additionally, its hemilabile character was demonstrated with an unusual kappa2-(P,N) coordination mode that is maintained in both the solid-state and in solution. Comparison of the structures of the mono(PNP) and bis(PNP) complexes 7, 9, 11-13 with their respective C5Me5 analogues 1-4 undoubtedly show that a more sterically congested environment is provided by the PNP ligand. The

  20. Mobility and Molecular Ions of Dimethyl Methyl Phosphonate, Methyl Salicylate, and Acetone.

    Science.gov (United States)

    1983-06-01

    Plasma Chromatography, is an analytical technique used to detect, identify, and quantify trace quantities of organic vapors in gaseous mixtures. IMS is...work has shown excellent detection sensitivity for trace quantities of pesticides,𔃻 TNT,2 nickel carbonyl , and phosphorus esters." Extensive work by...vacuum distilled at 4 torr to remove phosphite and other impurities. The acetone was ACS grade from laboratory stock. The methyl salicylate was ob

  1. DNA methylation changes detected by methylation-sensitive amplified polymorphism in two contrasting rice genotypes under salt stress.

    Science.gov (United States)

    Wang, Wensheng; Zhao, Xiuqin; Pan, Yajiao; Zhu, Linghua; Fu, Binying; Li, Zhikang

    2011-09-20

    DNA methylation, one of the most important epigenetic phenomena, plays a vital role in tuning gene expression during plant development as well as in response to environmental stimuli. In the present study, a methylation-sensitive amplified polymorphism (MSAP) analysis was performed to profile DNA methylation changes in two contrasting rice genotypes under salt stress. Consistent with visibly different phenotypes in response to salt stress, epigenetic markers classified as stable inter-cultivar DNA methylation differences were determined between salt-tolerant FL478 and salt-sensitive IR29. In addition, most tissue-specific DNA methylation loci were conserved, while many of the growth stage-dependent DNA methylation loci were dynamic between the two genotypes. Strikingly, salt stress induced a decrease in DNA methylation specifically in roots at the seedling stage that was more profound in IR29 than in the FL478. This result may indicate that demethylation of genes is an active epigenetic response to salt stress in roots at the seedling stage, and helps to further elucidate the implications of DNA methylation in crop growth and development. Copyright © 2011. Published by Elsevier Ltd.

  2. Protection against de novo methylation is instrumental in maintaining parent-of-origin methylation inherited from the gametes.

    Science.gov (United States)

    Proudhon, Charlotte; Duffié, Rachel; Ajjan, Sophie; Cowley, Michael; Iranzo, Julian; Carbajosa, Guillermo; Saadeh, Heba; Holland, Michelle L; Oakey, Rebecca J; Rakyan, Vardhman K; Schulz, Reiner; Bourc'his, Déborah

    2012-09-28

    Identifying loci with parental differences in DNA methylation is key to unraveling parent-of-origin phenotypes. By conducting a MeDIP-Seq screen in maternal-methylation free postimplantation mouse embryos (Dnmt3L-/+), we demonstrate that maternal-specific methylation exists very scarcely at midgestation. We reveal two forms of oocyte-specific methylation inheritance: limited to preimplantation, or with longer duration, i.e. maternally imprinted loci. Transient and imprinted maternal germline DMRs (gDMRs) are indistinguishable in gametes and preimplantation embryos, however, de novo methylation of paternal alleles at implantation delineates their fates and acts as a major leveling factor of parent-inherited differences. We characterize two new imprinted gDMRs, at the Cdh15 and AK008011 loci, with tissue-specific imprinting loss, again by paternal methylation gain. Protection against demethylation after fertilization has been emphasized as instrumental in maintaining parent-of-origin methylation inherited from the gametes. Here we provide evidence that protection against de novo methylation acts as an equal major pivot, at implantation and throughout life. Copyright © 2012 Elsevier Inc. All rights reserved.

  3. 78 FR 32157 - Methyl 5-(dimethylamino)-2-methyl-5-oxopentanoate; Exemption from the Requirement of a Tolerance

    Science.gov (United States)

    2013-05-29

    ... study showed no treatment- related effects on mating or fertility. There were no treatment-related... a petition to EPA under the Federal Food, Drug, and Cosmetic Act (FFDCA), requesting establishment... received and the nature of the adverse effects caused by methyl 5-(dimethylamino)-2-methyl-5- oxopentanoate...

  4. Analysis of DNA Methylation of Gracilariopsis lemaneiformis Under Temperature Stress Using the Methylation Sensitive Amplification Polymorphism (MSAP) Technique

    Science.gov (United States)

    Peng, Chong; Sui, Zhenghong; Zhou, Wei; Hu, Yiyi; Mi, Ping; Jiang, Minjie; Li, Xiaodong; Ruan, Xudong

    2018-06-01

    Gracilariopsis lemaneiformis is an economically important agarophyte, which contains high quality gel and shows a high growth rate. Wild population of G. lemaneiformis displayed resident divergence, though with a low genetic diversity as was revealed by amplified fragment length polymorphism (AFLP) and simple sequence repeat (SSR) analyses. In addition, different strains of G. lemaneiformis are diverse in morphology. The highly inconsistence between genetic background and physiological characteristics recommends strongly to the regulation at epigenetic level. In this study, the DNA methylation change in G. lemaneiformis among different generation branches and under different temperature stresses was assessed using methylation sensitive amplified polymorphism (MSAP) technique. It was shown that DNA methylation level among different generation branches was diverse. The full and total methylated DNA level was the lowest in the second generation branch and the highest in the third generation. The total methylation level was 61.11%, 60.88% and 64.12% at 15°C, 22°C and 26°C, respectively. Compared with the control group (22°C), the fully methylated and totally methylated ratios were increased in both experiment groups (15°C and 26°C). All of the cytosine methylation/demethylation transform (CMDT) was further analyzed. High temperature treatment could induce more CMDT than low temperature treatment did.

  5. Techno-economic and carbon footprint assessment of methyl crotonate and methyl acrylate production from wastewater-based polyhydroxybutyrate (PHB)

    NARCIS (Netherlands)

    Fernandez Dacosta, C.; Posada, John A.; Ramirez, C.A.

    2016-01-01

    This paper assesses whether a cleaner and more sustainable production of the chemical building blocks methyl crotonate (MC) and methyl acrylate (MA) can be obtained in an innovative process in which resource consumption, waste generation and environmental impacts are minimized by using

  6. Detection and discrimination of maintenance and de novo CpG methylation events using MethylBreak.

    Science.gov (United States)

    Hsu, William; Mercado, Augustus T; Hsiao, George; Yeh, Jui-Ming; Chen, Chung-Yung

    2017-05-15

    Understanding the principles governing the establishment and maintenance activities of DNA methyltransferases (DNMTs) can help in the development of predictive biomarkers associated with genetic disorders and diseases. A detection system was developed that distinguishes and quantifies methylation events using methylation-sensitive endonucleases and molecular beacon technology. MethylBreak (MB) is a 22-mer oligonucleotide with one hemimethylated and two unmethylated CpG sites, which are also recognition sites for Sau96I and SacII, and is attached to a fluorophore and a quencher. Maintenance methylation was quantified by fluorescence emission due to the digestion of SacII when the hemimethylated CpG site is methylated, which inhibits Sau96I cleavage. The signal difference between SacII digestion of both MB substrate and maintenance methylated MB corresponds to de novo methylation event. Our technology successfully discriminated and measured both methylation activities at different concentrations of MB and achieved a high correlation coefficient of R 2 =0.997. Additionally, MB was effectively applied to normal and cancer cell lines and in the analysis of enzymatic kinetics and RNA inhibition of recombinant human DNMT1. Copyright © 2017 Elsevier B.V. All rights reserved.

  7. Synthesis of N-methyl and N-11C-methyl spiperone by phase transfer catalysis in anhydrous solvent

    International Nuclear Information System (INIS)

    Omokawa, Hiroyoshi; Tanaka, Akira; Iio, Mayumi; Nishihara, Yoshiaki; Inoue, Osamu; Yamazaki, Toshio.

    1985-01-01

    Spiperone, a butyrophenone neuroleptic drug, has been used in binding studies of dopamine receptors. Langstrom et al. developed N- 11 C-methyl spiperone, and, in cooperate with Wagner et al., made it possible to visualize the distribution of dopamine receptors in the human brain in vivo. In this paper, we independently developed another synthetic method of N- 11 C-methyl spiperone using the phase transfer catalyst in an anhydrous solvent. Separation of the product is feasible only by passing the reactant solution through a Millipore filter and injecting it onto high pressure liquid chromatography (HPLC). The time required for the synthesis and purification of N- 11 C-methyl spiperone from 11 C-methyl iodide and spiperone was 20 min. Radiochemical yield exceeded 35 % against 11 C-methyl iodide without correcting decay of the radioactivity. (author)

  8. Genome-wide methylation analysis identifies differentially methylated CpG loci associated with severe obesity in childhood.

    Science.gov (United States)

    Huang, R C; Garratt, E S; Pan, H; Wu, Y; Davis, E A; Barton, S J; Burdge, G C; Godfrey, K M; Holbrook, J D; Lillycrop, K A

    2015-01-01

    Childhood obesity is a major public health issue. Here we investigated whether differential DNA methylation was associated with childhood obesity. We studied DNA methylation profiles in whole blood from 78 obese children (mean BMI Z-score: 2.6) and 71 age- and sex-matched controls (mean BMI Z-score: 0.1). DNA samples from obese and control groups were pooled and analyzed using the Infinium HumanMethylation450 BeadChip array. Comparison of the methylation profiles between obese and control subjects revealed 129 differentially methylated CpG (DMCpG) loci associated with 80 unique genes that had a greater than 10% difference in methylation (P-value obesity were validated using sodium bisulfite pyrosequencing across loci within the FYN, PIWIL4, and TAOK3 genes in individual subjects. Three CpG loci within FYN were hypermethylated in obese individuals (all P obesity was associated with lower methylation of CpG loci within PIWIL4 (P = 0.003) and TAOK3 (P = 0.001). After building logistic regression models, we determined that a 1% increase in methylation in TAOK3, multiplicatively decreased the odds of being obese by 0.91 (95% CI: 0.86 - 0.97), and an increase of 1% methylation in FYN CpG3, multiplicatively increased the odds of being obese by 1.03 (95% CI: 0.99 - 1.07). In conclusion, these findings provide evidence that childhood obesity is associated with specific DNA methylation changes in whole blood, which may have utility as biomarkers of obesity risk.

  9. CpG island methylator phenotype-low (CIMP-low) colorectal cancer shows not only few methylated CIMP-high-specific CpG islands, but also low-level methylation at individual loci.

    Science.gov (United States)

    Kawasaki, Takako; Ohnishi, Mutsuko; Nosho, Katsuhiko; Suemoto, Yuko; Kirkner, Gregory J; Meyerhardt, Jeffrey A; Fuchs, Charles S; Ogino, Shuji

    2008-03-01

    The CpG island methylator phenotype (CIMP or CIMP-high) with widespread promoter methylation is a distinct phenotype in colorectal cancer. However, the concept of CIMP-low with less extensive CpG island methylation is still evolving. Our aim is to examine whether density of methylation in individual CpG islands was different between CIMP-low and CIMP-high tumors. Utilizing MethyLight technology and 889 population-based colorectal cancers, we quantified DNA methylation (methylation index, percentage of methylated reference) at 14 CpG islands, including 8 CIMP-high-specific loci (CACNA1G, CDKN2A (p16), CRABP1, IGF2, MLH1, NEUROG1, RUNX3 and SOCS1). Methylation positivity in each locus was defined as methylation index>4. Low-level methylation (methylation index>0, CIMP-high-specific locus was significantly more common in 340 CIMP-low tumors (1/8-5/8 methylation-positive loci) than 133 CIMP-high tumors (> or =6/8 methylation-positive loci) and 416 CIMP-0 tumors (0/8 methylation-positive loci) (PCIMP-high, low-level methylation, was not persistently more prevalent in CIMP-low tumors. In conclusion, compared to CIMP-high and CIMP-0 tumors, CIMP-low colorectal cancers show not only few methylated CIMP-high-specific CpG islands, but also more frequent low-level methylation at individual loci. Our data may provide supporting evidence for a difference in pathogenesis of DNA methylation between CIMP-low and CIMP-high tumors.

  10. PRMT1-mediated arginine methylation controls ATXN2L localization

    Energy Technology Data Exchange (ETDEWEB)

    Kaehler, Christian; Guenther, Anika; Uhlich, Anja; Krobitsch, Sylvia, E-mail: krobitsc@molgen.mpg.de

    2015-05-15

    Arginine methylation is a posttranslational modification that is of importance in diverse cellular processes. Recent proteomic mass spectrometry studies reported arginine methylation of ataxin-2-like (ATXN2L), the paralog of ataxin-2, a protein that is implicated in the neurodegenerative disorder spinocerebellar ataxia type 2. Here, we investigated the methylation state of ATXN2L and its significance for ATXN2L localization. We first confirmed that ATXN2L is asymmetrically dimethylated in vivo, and observed that the nuclear localization of ATXN2L is altered under methylation inhibition. We further discovered that ATXN2L associates with the protein arginine-N-methyltransferase 1 (PRMT1). Finally, we showed that neither mutation of the arginine–glycine-rich motifs of ATXN2L nor methylation inhibition alters ATXN2L localization to stress granules, suggesting that methylation of ATXN2L is probably not mandatory. - Highlights: • ATXN2L is asymmetrically dimethylated in vivo. • ATXN2L interacts with PRMT1 under normal and stress conditions. • PRMT1-mediated dimethylation of ATXN2L controls its nuclear localization. • ATXN2L localization to stress granules appears independent of its methylation state.

  11. Epigenetics in Alzheimer's Disease: Perspective of DNA Methylation.

    Science.gov (United States)

    Qazi, Talal Jamil; Quan, Zhenzhen; Mir, Asif; Qing, Hong

    2018-02-01

    Research over the years has shown that causes of Alzheimer's disease are not well understood, but over the past years, the involvement of epigenetic mechanisms in the developing memory formation either under pathological or physiological conditions has become clear. The term epigenetics represents the heredity of changes in phenotype that are independent of altered DNA sequences. Different studies validated that cytosine methylation of genomic DNA decreases with age in different tissues of mammals, and therefore, the role of epigenetic factors in developing neurological disorders in aging has been under focus. In this review, we summarized and reviewed the involvement of different epigenetic mechanisms especially the DNA methylation in Alzheimer's disease (AD), late-onset Alzheimer's disease (LOAD), familial Alzheimer's disease (FAD), and autosomal dominant Alzheimer's disease (ADAD). Down to the minutest of details, we tried to discuss the methylation patterns like mitochondrial DNA methylation and ribosomal DNA (rDNA) methylation. Additionally, we mentioned some therapeutic approaches related to epigenetics, which could provide a potential cure for AD. Moreover, we reviewed some recent studies that validate DNA methylation as a potential biomarker and its role in AD. We hope that this review will provide new insights into the understanding of AD pathogenesis from the epigenetic perspective especially from the perspective of DNA methylation.

  12. Methylation-Sensitive High Resolution Melting (MS-HRM).

    Science.gov (United States)

    Hussmann, Dianna; Hansen, Lise Lotte

    2018-01-01

    Methylation-Sensitive High Resolution Melting (MS-HRM) is an in-tube, PCR-based method to detect methylation levels at specific loci of interest. A unique primer design facilitates a high sensitivity of the assays enabling detection of down to 0.1-1% methylated alleles in an unmethylated background.Primers for MS-HRM assays are designed to be complementary to the methylated allele, and a specific annealing temperature enables these primers to anneal both to the methylated and the unmethylated alleles thereby increasing the sensitivity of the assays. Bisulfite treatment of the DNA prior to performing MS-HRM ensures a different base composition between methylated and unmethylated DNA, which is used to separate the resulting amplicons by high resolution melting.The high sensitivity of MS-HRM has proven useful for detecting cancer biomarkers in a noninvasive manner in urine from bladder cancer patients, in stool from colorectal cancer patients, and in buccal mucosa from breast cancer patients. MS-HRM is a fast method to diagnose imprinted diseases and to clinically validate results from whole-epigenome studies. The ability to detect few copies of methylated DNA makes MS-HRM a key player in the quest for establishing links between environmental exposure, epigenetic changes, and disease.

  13. Application of methylation in improving plasmid transformation into Helicobacter pylori.

    Science.gov (United States)

    Zhao, Huilin; Xu, Linlin; Rong, Qianyu; Xu, Zheng; Ding, Yunfei; Zhang, Ying; Wu, Yulong; Li, Boqing; Ji, Xiaofei

    2018-05-23

    Helicobacter pylori is an important gastrointestinal pathogen. Its strains possess different levels of powerful restriction modification systems, which are significant barriers to genetic tools used for studying the role of functional genes in its pathogenesis. Methylating vectors in vitro was reported as an alternative to overcome this barrier in several bacteria. In this study we used two H. pylori-E. coli shuttle plasmids and several single/double-crossover homologous recombination gene-targeting plasmids, to test the role of methylation in H. pylori transformation. According to our results, transformants could be obtained only after shuttle plasmids were methylated before transformation. It is helpful in gene complementation and over-expression although at a low frequency. The frequency of gene-targeting transformation was also increased after methylation, especially for the single-crossover recombination plasmids, the transformants of which could only be obtained after methylation. For the double-crossover recombination targeting plasmids, the initial yield of transformants was 0.3-0.8 × 10 2 CFUs per microgram plasmid DNA. With the help of methylation, the yield was increased to 0.4-1.3 × 10 2 CFUs per microgram plasmid DNA. These results suggest that in vitro methylation can improve H. pylori transformation by different plasmids, which will benefit the pathogenic mechanism research. Copyright © 2018. Published by Elsevier B.V.

  14. Histone methylation and aging: Lessons learned from model systems

    Science.gov (United States)

    McCauley, Brenna S.; Dang, Weiwei

    2014-01-01

    Aging induces myriad cellular and, ultimately, physiological changes that cause a decline in an organism's functional capabilities. Although the aging process and pathways that regulate it have been extensively studied, only in the last decade have we begun to appreciate that dynamic histone methylation may contribute to this process. In this review, we discuss recent work implicating histone methylation in aging. Loss of certain histone methyltransferases and demethylases changes lifespan in invertebrates, and alterations in histone methylation in aged organisms regulate lifespan and aging phenotypes, including oxidative stress-induced hormesis in yeast, insulin signaling in Caenorhabiditis elegans and mammals, and the senescence-associated secretory phenotype in mammals. In all cases where histone methylation has been shown to impact aging and aging phenotypes, it does so by regulating transcription, suggesting that this is a major mechanism of its action in this context. Histone methylation additionally regulates or is regulated by other cellular pathways that contribute to or combat aging. Given the numerous processes that regulate aging and histone methylation, and are in turn regulated by them, the role of histone methylation in aging is almost certainly underappreciated. PMID:24859460

  15. High-resolution analysis of cytosine methylation in ancient DNA.

    Directory of Open Access Journals (Sweden)

    Bastien Llamas

    Full Text Available Epigenetic changes to gene expression can result in heritable phenotypic characteristics that are not encoded in the DNA itself, but rather by biochemical modifications to the DNA or associated chromatin proteins. Interposed between genes and environment, these epigenetic modifications can be influenced by environmental factors to affect phenotype for multiple generations. This raises the possibility that epigenetic states provide a substrate for natural selection, with the potential to participate in the rapid adaptation of species to changes in environment. Any direct test of this hypothesis would require the ability to measure epigenetic states over evolutionary timescales. Here we describe the first single-base resolution of cytosine methylation patterns in an ancient mammalian genome, by bisulphite allelic sequencing of loci from late Pleistocene Bison priscus remains. Retrotransposons and the differentially methylated regions of imprinted loci displayed methylation patterns identical to those derived from fresh bovine tissue, indicating that methylation patterns are preserved in the ancient DNA. Our findings establish the biochemical stability of methylated cytosines over extensive time frames, and provide the first direct evidence that cytosine methylation patterns are retained in DNA from ancient specimens. The ability to resolve cytosine methylation in ancient DNA provides a powerful means to study the role of epigenetics in evolution.

  16. Quantification of 5-methyl-2'-deoxycytidine in the DNA.

    Science.gov (United States)

    Giel-Pietraszuk, Małgorzata; Insińska-Rak, Małgorzata; Golczak, Anna; Sikorski, Marek; Barciszewska, Mirosława; Barciszewski, Jan

    2015-01-01

    Methylation at position 5 of cytosine (Cyt) at the CpG sequences leading to formation of 5-methyl-cytosine (m(5)Cyt) is an important element of epigenetic regulation of gene expression. Modification of the normal methylation pattern, unique to each organism, leads to the development of pathological processes and diseases, including cancer. Therefore, quantification of the DNA methylation and analysis of changes in the methylation pattern is very important from a practical point of view and can be used for diagnostic purposes, as well as monitoring of the treatment progress. In this paper we present a new method for quantification of 5-methyl-2'deoxycytidine (m(5)C) in the DNA. The technique is based on conversion of m(5)C into fluorescent 3,N(4)-etheno-5-methyl-2'deoxycytidine (εm(5)C) and its identification by reversed-phase high-performance liquid chromatography (RP-HPLC). The assay was used to evaluate m(5)C concentration in DNA of calf thymus and peripheral blood of cows bred under different conditions. This approach can be applied for measuring of 5-methylcytosine in cellular DNA from different cells and tissues.

  17. Are one or two dangerous? Methyl salicylate exposure in toddlers.

    Science.gov (United States)

    Davis, Jonathan E

    2007-01-01

    Serious toxicity can result from exposure to small amounts of methyl salicylate. Methyl salicylate is widely available as a component in many over-the-counter brands of creams, ointments, lotions, liniments and medicated oils intended for topical application to relieve musculoskeletal aches and pains. Among the most potent forms of methyl salicylate is oil of wintergreen (98% methyl salicylate). Other products with varying concentrations of methyl salicylate are ubiquitous throughout many parts of the world, including a number of products marketed as Asian herbal remedies. The toxic potential of all of these formulations is often underestimated by health care providers and the general public. A comprehensive review of the existing medical literature on methyl salicylate poisoning was performed, and data compiled over the past two decades by the American Association of Poison Control Centers (AAPCC) was examined. Methyl salicylate continues to be a relatively common source of pediatric exposures. Persistent reports of life-threatening and fatal toxicity were found. In children less than 6 years of age, a teaspoon (5 mL) or less of oil of wintergreen has been implicated in several well-documented deaths. More needs to be done to educate both health care providers and the general public regarding the dangers of these widely available formulations.

  18. Methylation screening of the TGFBI promoter in human lung and prostate cancer by methylation-specific PCR

    International Nuclear Information System (INIS)

    Shah, Jinesh N; Shao, Genze; Hei, Tom K; Zhao, Yongliang

    2008-01-01

    Hypermethylation of the TGFBI promoter has been shown to correlate with decreased expression of this gene in human tumor cell lines. In this study, we optimized a methylation-specific polymerase chain reaction (MSP) method and investigated the methylation status of the TGFBI promoter in human lung and prostate cancer specimens. Methylation-specific primers were designed based on the methylation profiles of the TGFBI promoter in human tumor cell lines, and MSP conditions were optimized for accurate and efficient amplification. Genomic DNA was isolated from lung tumors and prostatectomy tissues of prostate cancer patients, bisulfite-converted, and analyzed by MSP. Among 50 lung cancer samples, 44.0% (22/50) harbored methylated CpG sites in the TGFBI promoter. An analysis correlating gene methylation status with clinicopathological cancer features revealed that dense methylation of the TGFBI promoter was associated with a metastatic phenotype, with 42.9% (6/14) of metastatic lung cancer samples demonstrating dense methylation vs. only 5.6% (2/36) of primary lung cancer samples (p < 0.05). Similar to these lung cancer results, 82.0% (41/50) of prostate cancer samples harbored methylated CpG sites in the TGFBI promoter, and dense methylation of the promoter was present in 38.9% (7/18) of prostate cancer samples with the feature of locoregional invasiveness vs. only 19.4% (6/31) of prostate cancer samples without locoregional invasiveness (p < 0.05). Furthermore, promoter hypermethylation correlated with highly reduced expression of the TGFBI gene in human lung and prostate tumor cell lines. We successfully optimized a MSP method for the precise and efficient screening of TGFBI promoter methylation status. Dense methylation of the TGFBI promoter correlated with the extent of TGFBI gene silencing in tumor cell lines and was related to invasiveness of prostate tumors and metastatic status of lung cancer tumors. Thus, TGFBI promoter methylation can be used as a potential

  19. Quantitative DNA methylation analyses reveal stage dependent DNA methylation and association to clinico-pathological factors in breast tumors

    International Nuclear Information System (INIS)

    Klajic, Jovana; Tost, Jörg; Kristensen, Vessela N; Fleischer, Thomas; Dejeux, Emelyne; Edvardsen, Hege; Warnberg, Fredrik; Bukholm, Ida; Lønning, Per Eystein; Solvang, Hiroko; Børresen-Dale, Anne-Lise

    2013-01-01

    Aberrant DNA methylation of regulatory genes has frequently been found in human breast cancers and correlated to clinical outcome. In the present study we investigate stage specific changes in the DNA methylation patterns in order to identify valuable markers to understand how these changes affect breast cancer progression. Quantitative DNA methylation analyses of 12 candidate genes ABCB1, BRCCA1, CDKN2A, ESR1, GSTP1, IGF2, MGMT, HMLH1, PPP2R2B, PTEN, RASSF1A and FOXC1 was performed by pyrosequencing a series of 238 breast cancer tissue samples from DCIS to invasive tumors stage I to IV. Significant differences in methylation levels between the DCIS and invasive stage II tumors were observed for six genes RASSF1A, CDKN2A, MGMT, ABCB1, GSTP1 and FOXC1. RASSF1A, ABCB1 and GSTP1 showed significantly higher methylation levels in late stage compared to the early stage breast carcinoma. Z-score analysis revealed significantly lower methylation levels in DCIS and stage I tumors compared with stage II, III and IV tumors. Methylation levels of PTEN, PPP2R2B, FOXC1, ABCB1 and BRCA1 were lower in tumors harboring TP53 mutations then in tumors with wild type TP53. Z-score analysis showed that TP53 mutated tumors had significantly lower overall methylation levels compared to tumors with wild type TP53. Methylation levels of RASSF1A, PPP2R2B, GSTP1 and FOXC1 were higher in ER positive vs. ER negative tumors and methylation levels of PTEN and CDKN2A were higher in HER2 positive vs. HER2 negative tumors. Z-score analysis also showed that HER2 positive tumors had significantly higher z-scores of methylation compared to the HER2 negative tumors. Univariate survival analysis identifies methylation status of PPP2R2B as significant predictor of overall survival and breast cancer specific survival. In the present study we report that the level of aberrant DNA methylation is higher in late stage compared with early stage of invasive breast cancers and DCIS for genes mentioned above

  20. CpG methylation controls reactivation of HIV from latency.

    Directory of Open Access Journals (Sweden)

    Jana Blazkova

    2009-08-01

    Full Text Available DNA methylation of retroviral promoters and enhancers localized in the provirus 5' long terminal repeat (LTR is considered to be a mechanism of transcriptional suppression that allows retroviruses to evade host immune responses and antiretroviral drugs. However, the role of DNA methylation in the control of HIV-1 latency has never been unambiguously demonstrated, in contrast to the apparent importance of transcriptional interference and chromatin structure, and has never been studied in HIV-1-infected patients. Here, we show in an in vitro model of reactivable latency and in a latent reservoir of HIV-1-infected patients that CpG methylation of the HIV-1 5' LTR is an additional epigenetic restriction mechanism, which controls resistance of latent HIV-1 to reactivation signals and thus determines the stability of the HIV-1 latency. CpG methylation acts as a late event during establishment of HIV-1 latency and is not required for the initial provirus silencing. Indeed, the latent reservoir of some aviremic patients contained high proportions of the non-methylated 5' LTR. The latency controlled solely by transcriptional interference and by chromatin-dependent mechanisms in the absence of significant promoter DNA methylation tends to be leaky and easily reactivable. In the latent reservoir of HIV-1-infected individuals without detectable plasma viremia, we found HIV-1 promoters and enhancers to be hypermethylated and resistant to reactivation, as opposed to the hypomethylated 5' LTR in viremic patients. However, even dense methylation of the HIV-1 5'LTR did not confer complete resistance to reactivation of latent HIV-1 with some histone deacetylase inhibitors, protein kinase C agonists, TNF-alpha, and their combinations with 5-aza-2deoxycytidine: the densely methylated HIV-1 promoter was most efficiently reactivated in virtual absence of T cell activation by suberoylanilide hydroxamic acid. Tight but incomplete control of HIV-1 latency by Cp

  1. Effects of temperature and relative humidity on DNA methylation.

    Science.gov (United States)

    Bind, Marie-Abele; Zanobetti, Antonella; Gasparrini, Antonio; Peters, Annette; Coull, Brent; Baccarelli, Andrea; Tarantini, Letizia; Koutrakis, Petros; Vokonas, Pantel; Schwartz, Joel

    2014-07-01

    Previous studies have found relationships between DNA methylation and various environmental contaminant exposures. Associations with weather have not been examined. Because temperature and humidity are related to mortality even on non-extreme days, we hypothesized that temperature and relative humidity may affect methylation. We repeatedly measured methylation on long interspersed nuclear elements (LINE-1), Alu, and 9 candidate genes in blood samples from 777 elderly men participating in the Normative Aging Study (1999-2009). We assessed whether ambient temperature and relative humidity are related to methylation on LINE-1 and Alu, as well as on genes controlling coagulation, inflammation, cortisol, DNA repair, and metabolic pathway. We examined intermediate-term associations of temperature, relative humidity, and their interaction with methylation, using distributed lag models. Temperature or relative humidity levels were associated with methylation on tissue factor (F3), intercellular adhesion molecule 1 (ICAM-1), toll-like receptor 2 (TRL-2), carnitine O-acetyltransferase (CRAT), interferon gamma (IFN-γ), inducible nitric oxide synthase (iNOS), and glucocorticoid receptor, LINE-1, and Alu. For instance, a 5°C increase in 3-week average temperature in ICAM-1 methylation was associated with a 9% increase (95% confidence interval: 3% to 15%), whereas a 10% increase in 3-week average relative humidity was associated with a 5% decrease (-8% to -1%). The relative humidity association with ICAM-1 methylation was stronger on hot days than mild days. DNA methylation in blood cells may reflect biological effects of temperature and relative humidity. Temperature and relative humidity may also interact to produce stronger effects.

  2. Methylation signature of lymph node metastases in breast cancer patients

    International Nuclear Information System (INIS)

    Barekati, Zeinab; Radpour, Ramin; Lu, Qing; Bitzer, Johannes; Zheng, Hong; Toniolo, Paolo; Lenner, Per; Zhong, Xiao Yan

    2012-01-01

    Invasion and metastasis are two important hallmarks of malignant tumors caused by complex genetic and epigenetic alterations. The present study investigated the contribution of aberrant methylation profiles of cancer related genes, APC, BIN1, BMP6, BRCA1, CST6, ESR-b, GSTP1, P14 (ARF), P16 (CDKN2A), P21 (CDKN1A), PTEN, and TIMP3, in the matched axillary lymph node metastasis in comparison to the primary tumor tissue and the adjacent normal tissue from the same breast cancer patients to identify the potential of candidate genes methylation as metastatic markers. The quantitative methylation analysis was performed using the SEQUENOM’s EpiTYPER™ assay which relies on matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). The quantitative DNA methylation analysis of the candidate genes showed higher methylation proportion in the primary tumor tissue than that of the matched normal tissue and the differences were significant for the APC, BIN1, BMP6, BRCA1, CST6, ESR-b, P16, PTEN and TIMP3 promoter regions (P<0.05). Among those candidate methylated genes, APC, BMP6, BRCA1 and P16 displayed higher methylation proportion in the matched lymph node metastasis than that found in the normal tissue (P<0.05). The pathway analysis revealed that BMP6, BRCA1 and P16 have a role in prevention of neoplasm metastasis. The results of the present study showed methylation heterogeneity between primary tumors and metastatic lesion. The contribution of aberrant methylation alterations of BMP6, BRCA1 and P16 genes in lymph node metastasis might provide a further clue to establish useful biomarkers for screening metastasis

  3. Methylation of the chicken vitellogenin gene: influence of estradiol administration.

    Science.gov (United States)

    Meijlink, F C; Philipsen, J N; Gruber, M; Ab, G

    1983-01-01

    The degree of methylation of the chicken vitellogenin gene has been investigated. Upon induction by administration of estradiol to a rooster, methyl groups at specific sites near the 5'-end of the gene are eliminated. The process of demethylation is slower than the activation of the gene. Demethylation is therefore probably not a prerequisite to gene transcription. At least two other sites in the coding region of the gene are methylated in the liver of estrogenized roosters, but not in the liver of a laying hen, where the gene is naturally active. Images PMID:6298743

  4. What do unicellular organisms teach us about DNA methylation?

    Science.gov (United States)

    Harony, Hala; Ankri, Serge

    2008-05-01

    DNA methylation is an epigenetic hallmark that has been studied intensively in mammals and plants. However, knowledge of this phenomenon in unicellular organisms is scanty. Examining epigenetic regulation, and more specifically DNA methylation, in these organisms represents a unique opportunity to better understand their biology. The determination of their methylation status is often complicated by the presence of several differentiation stages in their life cycle. This article focuses on some recent advances that have revealed the unexpected nature of the epigenetic determinants present in protozoa. The role of the enigmatic DNA methyltransferase Dnmt2 in unicellular organisms is discussed.

  5. Heptyl vicianoside and methyl caramboside from sour star fruit.

    Science.gov (United States)

    Yang, Dan; Jia, Xuchao; Xie, Haihui

    2018-04-23

    Two new alkyl glycosides, heptyl vicianoside (1) and methyl 2-O-β-d-fucopyranosyl-α-l-arabinofuranoside (methyl caramboside, 4), were isolated from the sour fruit of Averrhoa carambola L. (Oxalidaceae), along with octyl vicianoside (2), cis-3-hexenyl rutinoside (3), and methyl α-d-fructofuranoside (5). Their structures were determined by spectroscopic and chemical methods. Compounds 2, 3, and 5 were obtained from the genus Averrhoa for the first time. All the compounds were evaluated for in vitro α-glucosidase, pancreatic lipase, and acetylcholinesterase inhibitory activities, but none of them were potent.

  6. Methyl group rotation and nuclear relaxation at low temperatures

    International Nuclear Information System (INIS)

    Zweers, A.E.

    1976-01-01

    This thesis deals with the proton spin-lattice relaxation of some methyl group compounds at liquid helium temperatures. In these molecular crystals, an energy difference between the ground and first rotational state of the methyl group occurs, the so-called tunnelling splitting, which is of the order of a few degrees Kelvin. This means that the high temperature approximation is inappropriate for the description of the occupation densities of the two lowest rotational levels. A description of the properties of the methyl group in connection with relaxation

  7. Study on the influence of optical electronegativity of fluoride host structures on the crystal field components' position of the [Xe]4f15d1-configuration of trivalent praseodymium

    International Nuclear Information System (INIS)

    Herden, Benjamin

    2014-03-01

    As alternative radiation sources for mercury containing lamps LEDs cover the normal range, but efficient alternatives for UV radiations are still not available. Xenon excimer discharge lamps could be candidate as alternatives to mercury low-pressure discharge lamps. The discharge wavelength of these lamps is 172 nm that has to be converted in other spectral ranges. The theses deals with trivalent praseodymium as activator ion in binary and ternary fluoride host structures. The host structure and the crystallographic position of the praseodymium ion influence the development of emissions line and bands and the energetic position of the emission. The results are explained by the interaction of the nephelauxetic effect and the crystal field splitting of 5d orbitals, called optical electronegativity.

  8. Electron diffraction study of the sillenites Bi12SiO20, Bi25FeO39 and Bi25InO39: Evidence of short-range ordering of oxygen-vacancies in the trivalent sillenites

    Directory of Open Access Journals (Sweden)

    Craig A. Scurti

    2014-08-01

    Full Text Available We present an electron diffraction study of three sillenites, Bi12SiO20, Bi25FeO39, and Bi25InO39 synthesized using the solid-state method. We explore a hypothesis, inspired by optical studies in the literature, that suggests that trivalent sillenites have additional disorder not present in the tetravalent compounds. Electron diffraction patterns of Bi25FeO39 and Bi25InO39 show streaks that confirm deviations from the ideal sillenite structure. Multi-slice simulations of electron-diffraction patterns are presented for different perturbations to the sillenite structure - partial substitution of the M site by Bi3+, random and ordered oxygen-vacancies, and a frozen-phonon model. Although comparison of experimental data to simulations cannot be conclusive, we consider the streaks as evidence of short-range ordered oxygen-vacancies.

  9. Chemical behaviour of trivalent and pentavalent americium in saline NaCl-solutions. Studies of transferability of laboratory data to natural conditions. Interim report. Reported period: 1.2.1993-31.12.1993

    International Nuclear Information System (INIS)

    Runde, W.; Kim, J.I.

    1994-09-01

    In order to clarify the chemical behaviour of Americium in saline aqueous systems relevant for final storage this study deals with the chemical reactions of trivalent and pentavalent Americium in NaCl-solutions under the influence of radiolysis from its own alpha radiation. The focus of the study was on investigating the geologically relevant reactions, such as hydrolysis or carbonate- and chloride complexing in solid-liquid equilibriums. Comprehensive measurements on solubility and spectroscopic studies in NaCl-solutions were carried out in a CO 2 -free atmosphere and 10 -2 atm CO 2 partial pressure. Identification and characterisation of the AM (III) and AM(V) solid phases were supplemented by structural research with the chemically analogue EU (III) and Np(V) compounds. The alpha-radiation induced radiolysis in saline NaCl solutions and the redox behaviour of Americium which was influenced thereby were spectroscopically quantified. (orig.) [de

  10. Rapid analysis of heterogeneously methylated DNA using digital methylation-sensitive high resolution melting: application to the CDKN2B (p15) gene

    DEFF Research Database (Denmark)

    Candiloro, Ida Lm; Mikeska, Thomas; Hokland, Peter

    2008-01-01

    ABSTRACT: BACKGROUND: Methylation-sensitive high resolution melting (MS-HRM) methodology is able to recognise heterogeneously methylated sequences by their characteristic melting profiles. To further analyse heterogeneously methylated sequences, we adopted a digital approach to MS-HRM (dMS-HRM) t......ABSTRACT: BACKGROUND: Methylation-sensitive high resolution melting (MS-HRM) methodology is able to recognise heterogeneously methylated sequences by their characteristic melting profiles. To further analyse heterogeneously methylated sequences, we adopted a digital approach to MS-HRM (d......MS-HRM) that involves the amplification of single templates after limiting dilution to quantify and to determine the degree of methylation. We used this approach to study methylation of the CDKN2B (p15) cell cycle progression inhibitor gene which is inactivated by DNA methylation in haematological malignancies...... the methylated alleles and assess the degree of methylation. Direct sequencing of selected dMS-HRM products was used to determine the exact DNA methylation pattern and confirmed the degree of methylation estimated by dMS-HRM. CONCLUSION: dMS-HRM is a powerful technique for the analysis of methylation in CDKN2B...

  11. Methylation-sensitive amplified polymorphism-based genome-wide analysis of cytosine methylation profiles in Nicotiana tabacum cultivars.

    Science.gov (United States)

    Jiao, J; Wu, J; Lv, Z; Sun, C; Gao, L; Yan, X; Cui, L; Tang, Z; Yan, B; Jia, Y

    2015-11-26

    This study aimed to investigate cytosine methylation profiles in different tobacco (Nicotiana tabacum) cultivars grown in China. Methylation-sensitive amplified polymorphism was used to analyze genome-wide global methylation profiles in four tobacco cultivars (Yunyan 85, NC89, K326, and Yunyan 87). Amplicons with methylated C motifs were cloned by reamplified polymerase chain reaction, sequenced, and analyzed. The results show that geographical location had a greater effect on methylation patterns in the tobacco genome than did sampling time. Analysis of the CG dinucleotide distribution in methylation-sensitive polymorphic restriction fragments suggested that a CpG dinucleotide cluster-enriched area is a possible site of cytosine methylation in the tobacco genome. The sequence alignments of the Nia1 gene (that encodes nitrate reductase) in Yunyan 87 in different regions indicate that a C-T transition might be responsible for the tobacco phenotype. T-C nucleotide replacement might also be responsible for the tobacco phenotype and may be influenced by geographical location.

  12. A novel trivalent HPV 16/18/58 vaccine with anti-HPV 16 and 18 neutralizing antibody responses comparable to those induced by the Gardasil quadrivalent vaccine in rhesus macaque model

    Directory of Open Access Journals (Sweden)

    Fei Yin

    2017-06-01

    Full Text Available Persistent infection with human papillomavirus (HPV is a key factor in the development of precancerous lesions and invasive cervical cancer. Prophylactic vaccines to immunize against HPV are an effective approach to reducing HPV related disease burden. In this study, we investigated the immunogenicity and dosage effect of a trivalent HPV 16/18/58 vaccine (3vHPV produced in Escherichia coli (E.coli, with Gardasil quadrivalent vaccine (4vHPV, Merck & Co. as a positive control. Sera collected from rhesus macaques vaccinated with three dosage formulations of 3vHPV (termed low-, mid-, and high-dosage formulations, respectively, and the 4vHPV vaccine were analyzed by both Pseudovirus-Based Neutralization Assay (PBNA and Enzyme-Linked Immunosorbent Assay (ELISA. Strong immune responses against HPV 16/18/58 were successfully elicited, and dosage-dependence was observed, with likely occurrence of immune interference between different L1-VLP antigens. HPV 16/18 specific neutralizing antibody (nAb and total immunoglobulin G (IgG antibody responses in rhesus macaques receiving 3vHPV at the three dosages tested were generally non-inferior to those observed in rhesus macaques receiving 4vHPV throughout the study period. Particularly, HPV 18 nAb titers induced by the mid-dosage formulation that contained the same amounts of HPV 16/18 L1-VLPs as Gardasil 4vHPV were between 7.3 to 12.7-fold higher compared to the positive control arm from weeks 24–64. The durability of antibody responses specific to HPV 16/18 elicited by 3vHPV vaccines was also shown to be non-inferior to that associated with Gardasil 4vHPV. Keywords: Human papillomavirus, HPV 16/18/58, GMTs, Trivalent, Immunogenicity

  13. Analysis of DNA methylation of maize in response to osmotic and salt stress based on methylation-sensitive amplified polymorphism.

    Science.gov (United States)

    Tan, Ming-pu

    2010-01-01

    Water stress is known to alter cytosine methylation, which generally represses transcription. However, little is known about the role of methylation alteration in maize under osmotic stress. Here, methylation-sensitive amplified polymorphism (MSAP) was used to screen PEG- or NaCl-induced methylation alteration in maize seedlings. The sequences of 25 differentially amplified fragments relevant to stress were successfully obtained. Two stress-specific fragments from leaves, LP166 and LPS911, shown to be homologous to retrotransposon Gag-Pol protein genes, suggested that osmotic stress-induced methylation of retrotransposons. Three MSAP fragments, representing drought-induced or salt-induced methylation in leaves, were homologous to a maize aluminum-induced transporter. Besides these, heat shock protein HSP82, Poly [ADP-ribose] polymerase 2, Lipoxygenase, casein kinase (CK2), and dehydration-responsive element-binding (DREB) factor were also homologs of MSAP sequences from salt-treated roots. One MSAP fragment amplified from salt-treated roots, designated RS39, was homologous to the first intron of maize protein phosphatase 2C (zmPP2C), whereas - LS103, absent from salt-treated leaves, was homologous to maize glutathione S-transferases (zmGST). Expression analysis showed that salt-induced intron methylation of root zmPP2C significantly downregulated its expression, while salt-induced demethylation of leaf zmGST weakly upregulated its expression. The results suggested that salinity-induced methylation downregulated zmPP2C expression, a negative regulator of the stress response, while salinity-induced demethylation upregulated zmGST expression, a positive effecter of the stress response. Altered methylation, in response to stress, might also be involved in stress acclimation. Copyright 2009 Elsevier Masson SAS. All rights reserved.

  14. Transgenerational epigenetics: Inheritance of global cytosine methylation and methylation-related epigenetic markers in the shrub Lavandula latifolia.

    Science.gov (United States)

    Herrera, Carlos M; Alonso, Conchita; Medrano, Mónica; Pérez, Ricardo; Bazaga, Pilar

    2018-04-01

    The ecological and evolutionary significance of natural epigenetic variation (i.e., not based on DNA sequence variants) variation will depend critically on whether epigenetic states are transmitted from parents to offspring, but little is known on epigenetic inheritance in nonmodel plants. We present a quantitative analysis of transgenerational transmission of global DNA cytosine methylation (= proportion of all genomic cytosines that are methylated) and individual epigenetic markers (= methylation status of anonymous MSAP markers) in the shrub Lavandula latifolia. Methods based on parent-offspring correlations and parental variance component estimation were applied to epigenetic features of field-growing plants ('maternal parents') and greenhouse-grown progenies. Transmission of genetic markers (AFLP) was also assessed for reference. Maternal parents differed significantly in global DNA cytosine methylation (range = 21.7-36.7%). Greenhouse-grown maternal families differed significantly in global methylation, and their differences were significantly related to maternal origin. Methylation-sensitive amplified polymorphism (MSAP) markers exhibited significant transgenerational transmission, as denoted by significant maternal variance component of marker scores in greenhouse families and significant mother-offspring correlations of marker scores. Although transmission-related measurements for global methylation and MSAP markers were quantitatively lower than those for AFLP markers taken as reference, this study has revealed extensive transgenerational transmission of genome-wide global cytosine methylation and anonymous epigenetic markers in L. latifolia. Similarity of results for global cytosine methylation and epigenetic markers lends robustness to this conclusion, and stresses the value of considering both types of information in epigenetic studies of nonmodel plants. © 2018 Botanical Society of America.

  15. Analysis of DNA methylation of perennial ryegrass under drought using the methylation-sensitive amplification polymorphism (MSAP) technique.

    Science.gov (United States)

    Tang, Xiao-Mei; Tao, Xiang; Wang, Yan; Ma, Dong-Wei; Li, Dan; Yang, Hong; Ma, Xin-Rong

    2014-12-01

    Perennial ryegrass (Lolium perenne), an excellent grass for forage and turf, is widespread in temperate regions. Drought is an important factor that limits its growth, distribution, and yield. DNA methylation affects gene expression and plays an important role in adaptation to adverse environments. In this study, the DNA methylation changes in perennial ryegrass under drought stress were assessed using methylation-sensitive amplified polymorphism (MSAP). After 15 days of drought stress treatment, the plant height was less than half of the control, and the leaves were smaller and darker. Genome-wide, a total of 652 CCGG sites were detected by MSAP. The total methylation level was 57.67 and 47.39 % in the control and drought treatment, respectively, indicating a decrease of 10.28 % due to drought exposure. Fifteen differentially displayed DNA fragments in MSAP profiles were cloned for sequencing analysis. The results showed that most of the genes involved in stress responses. The relative expression levels revealed that three demethylated fragments were up-regulated. The expression of a predicted retrotransposon increased significantly, changing from hypermethylation to non-methylation. Although the extent of methylation in two other genes decreased, the sites of methylation remained, and the expression increased only slightly. All of these results suggested that drought stress decreased the total DNA methylation level in perennial ryegrass and demethylation up-regulated related gene expressions and that the extent of methylation was negatively correlated with expression. Overall, the induced epigenetic changes in genome probably are an important regulatory mechanism for acclimating perennial ryegrass to drought and possibly other environmental stresses.

  16. IGFBP3 Promoter Methylation in Colorectal Cancer: Relationship with Microsatellite Instability, CpG Island Methylator Phenotype, p53

    Directory of Open Access Journals (Sweden)

    Takako Kawasaki

    2007-12-01

    Full Text Available Insulin-like growth factor binding protein 3 (IGFBP3, which is induced by wild-type p53, regulates IGF and interacts with the TGF-β pathway. IGFBP3 promoter methylation may occur in colorectal cancer with or without the CpG island methylator phenotype (CIMP, which is associated with microsatellite instability (MSI and TGFBR2 mutation. We examined the relationship between IGFBP3 methylation, p53 expression, CIMP and MSI in 902 population-based colorectal cancers. Utilizing real-time PCR (MethyLight, we quantified promoter methylation in IGFBP3 and eight other CIMP-high-specific promoters (CACNA1G, CDKN2A, CRABP1, IGF2, MLH1, NEUROG1, RUNX3, and SOCS1. IGFBP3 methylation was far more frequent in non-MSI-high CIMP-high tumors (85% = 35/41 than in MSI-high CIMPhigh (49% = 44/90, P < .0001, MSI-high non-CIMP-high (17% = 6/36, P < .0001, non-MSI-high non-CIMP-high tumors (22% = 152/680, P < .0001. Among CIMPhigh tumors, the inverse relationship between MSI and IGFBP3 methylation persisted in p53-negative tumors (P < .0001, but not in p53-positive tumors. IGFBP3 methylation was associated inversely with TGFBR2 mutation in MSI-high non-CIMP-high tumors (P = .02. In conclusion, IGFBP3 methylation is inversely associated with MSI in CIMP-high colorectal cancers, this relationship is limited to p53-negative tumors. Our data suggest complex relationship between global genomic/epigenomic phenomena (such as MSI/ CIMP, single molecular events (e.g., IGFBP3 methylation, TP53 mutation, TGFBR2 mutation, the related pathways.

  17. Combustion characteristics of the mustard methyl esters

    International Nuclear Information System (INIS)

    Bannikov, M.G.; Vasilev, I.P.

    2011-01-01

    Mustard Methyl Esters (further bio diesel) and regular diesel fuel were tested in direct injection diesel engine. Analysis of experimental data was supported by an analysis of fuel injection and combustion characteristics. Engine fuelled with bio diesel had increased brake specific fuel consumption, reduced nitrogen oxides emission and smoke opacity, moderate increase in carbon monoxide emission with essentially unchanged unburned hydrocarbons emission. Increase in fuel consumption was attributed to lesser heating value of bio diesel and partially to decreased fuel conversion efficiency. Analysis of combustion characteristics revealed earlier start of injection and shorter ignition delay period of bio diesel. Resulting decrease in maximum rate of heat release and cylinder pressure was the most probable reason for reduced emission of nitrogen oxides. Analysis of combustion characteristics also showed that cetane index determined by ASTM Method D976 is not a proper measure of ignition quality of bio diesel. Conclusion was made on applicability of mustard oil as a source for commercial production of bio diesel in Pakistan. Potentialities of on improving combustion and emissions characteristics of diesel engine by reformulating bio diesel were discussed. (author)

  18. Methyl and ethyl soybean esters production

    Energy Technology Data Exchange (ETDEWEB)

    Pighinelli, Anna Leticia Montenegro Turtelli; Park, Kil Jin; Zorzeto, Thais Queiroz [Universidade Estadual de Campinas (FEAGRI/UNICAMP), SP (Brazil). Fac. de Engenharia Agricola], E-mail: annalets@feagri.unicamp.br; Bevilaqua, Gabriela [Universidade Estadual de Campinas (IQ/UNICAMP), SP (Brazil). Inst. de Quimica

    2008-07-01

    Biodiesel is a fuel obtained from triglycerides found in nature, like vegetable oils and animal fats. Nowadays it has been the subject of many researches impulses by the creation of the Brazilian law that determined the blend of 2% of biodiesel with petrodiesel. Basically, there are no limitations on the oilseed type for chemical reaction, but due to high cost of this major feedstock, it is important to use the grain that is available in the region of production. Soybean is the oilseed mostly produced in Brazil and its oil is the only one that is available in enough quantity to supply the current biodiesel demand. The objective of this work was to study the effects of reaction time and temperature on soybean oil transesterification reaction with ethanol and methanol. A central composite experimental design with five variation levels was used and response surface methodology applied for the data analysis. The statistical analysis of the results showed that none of the factors affected the ethyl esters production. However, the methyl esters production suffered the influence of temperature (linear effect), reaction time (linear and quadratic) and interaction of these two variables. None of the generated models showed significant regression consequently it was not possible to build the response surface. The experiments demonstrated that methanol is the best alcohol for transesterification reactions and the ester yield was up to 85%. (author)

  19. Developmental immunotoxicity testing of 4-methyl anisole.

    Science.gov (United States)

    Tonk, Elisa C M; Verhoef, Aart; Gremmer, Eric R; van Loveren, Henk; Piersma, Aldert H

    2015-07-01

    The developmental immunotoxicity of 4-methyl anisole (4MA) was investigated in the rat. Four study designs were used, with either premating or post-weaning onset of exposure, continued to postnatal day 50, and with or without additional oral gavage of pups from postnatal day 10 onward. Reduced litter size (benchmark dose lower confidence limit (BMDL) 80mg/kg bw/day) was the most sensitive developmental parameter, with pup relative organ weight effects observed at similar BMDLs, in the absence of maternal toxicity. Eosinophil numbers were reduced at lower doses (BMDL 16mg/kg bw/day). KLH challenge resulted in increased IL-13 and TNF-α responses, and variably reduced IgG production (BMDL 27mg/kg bw/day). T4 levels were reduced by 11% at maximum with a BMDL of 73mg/kg bw/day. Differences between exposure cohorts were limited and were considered to be without biological significance. This study shows that 4MA induces developmental immunotoxicity at doses below those inducing developmental and general toxicity. These observations being independent of the study designs applied suggest that the post-weaning period, included in all designs, is the most relevant sensitive period for inducing 4MA mediated developmental immunotoxicity. Moreover, this study stresses the importance of including developmental immunotoxicity testing by default in regulatory toxicology. Copyright © 2015 Elsevier Inc. All rights reserved.

  20. Synthesis of methyl ester sulphonate by sulfonation of soybean oil methyl ester for chemical flooding application

    International Nuclear Information System (INIS)

    Richie Adi Putra; Renisa Ismayanti; Agam Duma Kalista W

    2018-01-01

    This research has accomplished the synthesis of Surfactant Methyl Ester Sulphonate from Methyl Soyate and Sodium Bisulfite as sulfonating agent. The Steps of the synthesis were reaction, purification, neutralization, and separation. The reaction done by several variated condition such as Reaction Temperature (100, 110, 120)°C, Reaction time (210, 270, 330)minute, and the mole ratio between Methyl Soyate and NaHSO 3 (1:1, 1:1.5, 1:2) with 1.5 % of Al 2 O 3 as catalyst of sulfonation reaction. The purification process was conducted at 55 °C and 60 minute by adding Methanol 35 % v/v. The neutralization done was conducted by 20 % of NaOH until pH 6-8. And the rest of the methanol are separated from MES using rotary evaporator. MES which is pass the compatibility Test is MES at the condition of reaction (100 °C, 210 minute and 1 : 2 mole ratio).This MES has tested by FT - IR to see the existence of the Sulphonate group.The FT-IR test result has shown the existence of the Sulphonate group at wave length between 1000 until 1300 cm -1 . Which is the highest peak at 1176 cm-1. From the qualitative test above, then the MES performed by IFT Test with light oil of X- field as comparison. The IFT results has shown a decrease of the interfacial tensions between 12,000 ppm of brine water and the light oil with addition of 0.3 % (v/v) MES, from 3.36 dyne/cm 2 to 1.54 dyne/cm 2 . (author)

  1. (E-2-Methyl-6-{[(5-methylpyridin-2-ylimino]methyl}phenol

    Directory of Open Access Journals (Sweden)

    Md. Azharul Arafath

    2017-01-01

    Full Text Available In the title compound, C14H14N2O, the dihedral angle between the aromatic rings is 5.54 (9°. The conformation is reinforced by an intramolecular O—H...N hydrogen bond, which closes an S(6 ring. The pyridine N atom and methyl group lie to opposite sides of the molecule. In the crystal, the molecules are linked into a zigzag chain propagating in [0-11] by weak C—H...O hydrogen bonds.

  2. 4-Methyl-N-(1-methyl-1H-indazol-5-yl)benzene­sulfonamide

    Science.gov (United States)

    Chicha, Hakima; Oulemda, Bassou; Rakib, El Mostapha; Saadi, Mohamed; El Ammari, Lahcen

    2013-01-01

    In the title compound, C15H15N3O2S, the fused ring system is close to planar, the largest deviation from the mean plane being 0.030 (2) Å, and makes a dihedral angle of 48.84 (9)° with the benzene ring belonging to the methyl­benzene­sulfonamide moiety. In the crystal, mol­ecules are ­connected through N—H⋯N hydrogen bonds and weak C—H⋯O contacts, forming a two-dimensional network parallel to (001). PMID:24427093

  3. SYNTHESIS AND POLYMERIZATION OF GEM-METHYL(VINYLBENZYL)TETRACHLOROCYCLOTRIPHOSPHAZENE

    NARCIS (Netherlands)

    BOSSCHER, G; VANDEGRAMPEL, JC

    A new styrene-substituted chlorocyclotriphosphazene, gem-methyl(vinylbenzyl) tetrachlorocyclotriphosphazene, has been prepared from vinylbenzylmagnesium chloride and hexachlorocyclotriphosphazene. The organosubstituted chlorocyclotriphosphazene has been used in radical homo- and copolymerization

  4. Methylation Integration (Mint) | Informatics Technology for Cancer Research (ITCR)

    Science.gov (United States)

    A comprehensive software pipeline and set of Galaxy tools/workflows for integrative analysis of genome-wide DNA methylation and hydroxymethylation data. Data types can be either bisulfite sequencing and/or pull-down methods.

  5. Decoding the regulatory landscape of medulloblastoma using DNA methylation sequencing

    NARCIS (Netherlands)

    Hovestadt, Volker; Jones, David T. W.; Picelli, Simone; Wang, Wei; Kool, Marcel; Northcott, Paul A.; Sultan, Marc; Stachurski, Katharina; Ryzhova, Marina; Warnatz, Hans-Jörg; Ralser, Meryem; Brun, Sonja; Bunt, Jens; Jäger, Natalie; Kleinheinz, Kortine; Erkek, Serap; Weber, Ursula D.; Bartholomae, Cynthia C.; von Kalle, Christof; Lawerenz, Chris; Eils, Jürgen; Koster, Jan; Versteeg, Rogier; Milde, Till; Witt, Olaf; Schmidt, Sabine; Wolf, Stephan; Pietsch, Torsten; Rutkowski, Stefan; Scheurlen, Wolfram; Taylor, Michael D.; Brors, Benedikt; Felsberg, Jörg; Reifenberger, Guido; Borkhardt, Arndt; Lehrach, Hans; Wechsler-Reya, Robert J.; Eils, Roland; Yaspo, Marie-Laure; Landgraf, Pablo; Korshunov, Andrey; Zapatka, Marc; Radlwimmer, Bernhard; Pfister, Stefan M.; Lichter, Peter

    2014-01-01

    Epigenetic alterations, that is, disruption of DNA methylation and chromatin architecture, are now acknowledged as a universal feature of tumorigenesis. Medulloblastoma, a clinically challenging, malignant childhood brain tumour, is no exception. Despite much progress from recent genomics studies,

  6. DNA Methylation: An Epigenetic Risk Factor in Preterm Birth

    Science.gov (United States)

    Menon, Ramkumar; Conneely, Karen N.; Smith, Alicia K.

    2012-01-01

    Spontaneous preterm birth (PTB; birth prior to 37 weeks of gestation) is a complex phenotype with multiple risk factors that complicate our understanding of its etiology. A number of recent studies have supported the hypothesis that epigenetic modifications such as DNA methylation induced by pregnancy-related risk factors may influence the risk of PTB or result in changes that predispose a neonate to adult-onset diseases. The critical role of timing of gene expression in the etiology of PTB makes it a highly relevant disorder in which to examine the potential role of epigenetic changes. Because changes in DNA methylation patterns can result in long-term consequences, it is of critical interest to identify the epigenetic patterns associated with adverse pregnancy outcomes. This review examines the potential role of DNA methylation as a risk factor for PTB and discusses several issues and limitations that should be considered when planning DNA methylation studies. PMID:22228737

  7. RARβ gene methylation is a candidate for primary glioblastoma ...

    African Journals Online (AJOL)

    Methods: In our study, tumor samples were collected during surgical resection by ... logically active form of vitamin A. RARβ is important ... RARβ methylation in 23 cases of grade II-IV tumors. ..... Piperi, C., Themistocleous, M.S., Papavassiliou,.

  8. Physicochemical, electrical and optical studies of methyl-3-(2 ...

    Indian Academy of Sciences (India)

    Administrator

    crystal methyl-3-(2-furylmethylidene) carbazate, which was grown by employing the slow ... exhibit Type-I phase matching. .... load, a the resistance of the material to initial penetration, ... using Wooster's empirical relation, which is given as.

  9. Parental epigenetic difference in DNA methylation-level may play ...

    African Journals Online (AJOL)

    Jane

    2011-08-22

    Aug 22, 2011 ... We found that a specific type of DNA methylation-level difference, that is, relative CHG (H ... eukaryotes and is particularly abundant in higher plants, ..... characterization of a set of disease resistance-gene analogs (RGAs).

  10. Synthesis of [methyl-[sup 14]C]-N-methylputrescine

    Energy Technology Data Exchange (ETDEWEB)

    Secor, H.V.; Izac, R.R.; Hassam, S.B.; Frisch, A.F. (Philip Morris Research Center, Richmond, VA (United States))

    1994-05-01

    [Methyl-[sup 14]C]-N-methylputrescine was prepared from [[sup 14]C]methylamine hydrochloride in five steps. Reaction of benzaldehyde and [[sup 14]C]methylamine (10 mCi) followed by catalytic hydrogenation yielded [methyl-[sup 14]C]-N-methylbenzylamine. The key step in this process is the alkylation of [methyl-[sup 14]C]-N-methylbenzylamine in aqueous medium with 4-bromobutyronitrile. The radiochemical purity of the final product after two successive catalytic hydrogenations was in excess of 97%. The radiochemical yields in two successive runs were 26 and 38%, based on starting [[sup 14]C]methylamine, with specific activities of 22 and 23 mCi/mmol, respectively. This sequence provides a convenient and efficient regioselective radiosynthesis of [methyl-[sup 14]C]-N-methylputrescine. (author).

  11. Clinical Utility of promoter methylation of the tumor suppressor ...

    African Journals Online (AJOL)

    Marwa H. Saied

    nosis and shortage of treatment facilities, resulting in a high pro- portion of .... Data analysis was performed using the software package SPSS ... out of 20 were negative for methylation) in fibroadenoma and con- .... For instance, in a big cohort.

  12. Methyl Bromide Commodity Fumigation Buffer Zone Lookup Tables

    Science.gov (United States)

    Product labels for methyl bromide used in commodity and structural fumigation include requirements for buffer zones around treated areas. The information on this page will allow you to find the appropriate buffer zone for your planned application.

  13. RNA-directed DNA methylation: Mechanisms and functions

    KAUST Repository

    Mahfouz, Magdy M.

    2010-01-01

    Epigenetic RNA based gene silencing mechanisms play a major role in genome stability and control of gene expression. Transcriptional gene silencing via RNA-directed DNA methylation (RdDM) guides the epigenetic regulation of the genome in response

  14. Oral Methylated N-Aryl Chitosan Derivatives for Inducing Immune ...

    African Journals Online (AJOL)

    TM-CM-CS) and methylated N-(4-pyridinylmethyl) chitosan (TM-Py-CS), with Eqiva degree (equivalent degree) were studied by in vitro absorption enhancement on the transepithelial electrical resistance (TEER) in Caco-2 cell monolayers as ...

  15. Changes of host DNA methylation in domestic chickens infected with ...

    Indian Academy of Sciences (India)

    FEI WANG

    2017-09-15

    Sep 15, 2017 ... Gene interaction network analysis of differentially methylated genes in the promoter .... sequencing library and sequenced by HiSeq 2000 Illumina. The chicken ... annotation system (KOBAS) (Xie et al. 2011), which pro-.

  16. The fluorescence behaviour of methyl and phenyl salicylate

    Science.gov (United States)

    Ford, D.; Thistlethwaite, P. J.; Woolfe, G. J.

    1980-01-01

    Fluorcsccnce lifetimes tor the 450 nm emission of methyl and phenyl salicylate in various solvents have been measured. Qucnching studics on the 340 nm fluorescence of these molecules point to the existence of three distinct ground state conformers.

  17. Absolute photoionization cross-section of the methyl radical.

    Science.gov (United States)

    Taatjes, Craig A; Osborn, David L; Selby, Talitha M; Meloni, Giovanni; Fan, Haiyan; Pratt, Stephen T

    2008-10-02

    The absolute photoionization cross-section of the methyl radical has been measured using two completely independent methods. The CH3 photoionization cross-section was determined relative to that of acetone and methyl vinyl ketone at photon energies of 10.2 and 11.0 eV by using a pulsed laser-photolysis/time-resolved synchrotron photoionization mass spectrometry method. The time-resolved depletion of the acetone or methyl vinyl ketone precursor and the production of methyl radicals following 193 nm photolysis are monitored simultaneously by using time-resolved synchrotron photoionization mass spectrometry. Comparison of the initial methyl signal with the decrease in precursor signal, in combination with previously measured absolute photoionization cross-sections of the precursors, yields the absolute photoionization cross-section of the methyl radical; sigma(CH3)(10.2 eV) = (5.7 +/- 0.9) x 10(-18) cm(2) and sigma(CH3)(11.0 eV) = (6.0 +/- 2.0) x 10(-18) cm(2). The photoionization cross-section for vinyl radical determined by photolysis of methyl vinyl ketone is in good agreement with previous measurements. The methyl radical photoionization cross-section was also independently measured relative to that of the iodine atom by comparison of ionization signals from CH3 and I fragments following 266 nm photolysis of methyl iodide in a molecular-beam ion-imaging apparatus. These measurements gave a cross-section of (5.4 +/- 2.0) x 10(-18) cm(2) at 10.460 eV, (5.5 +/- 2.0) x 10(-18) cm(2) at 10.466 eV, and (4.9 +/- 2.0) x 10(-18) cm(2) at 10.471 eV. The measurements allow relative photoionization efficiency spectra of methyl radical to be placed on an absolute scale and will facilitate quantitative measurements of methyl concentrations by photoionization mass spectrometry.

  18. Interaction of trivalent lanthanides and actinides with aluminium oxides and hydroxides; Wechselwirkung von dreiwertigen Lanthaniden und Actiniden mit Aluminiumoxiden und -hydroxiden

    Energy Technology Data Exchange (ETDEWEB)

    Kupcik, Tomas

    2011-10-28

    The subject of the present work is the interaction of trivalent actinides Cm(III) and lanthanides (Eu(III) and Gd(III)) with aluminium oxides and -hydroxides, namely corundum/sapphire (α-Al{sub 2}O{sub 3}), gibbsite (α-Al(OH){sub 3}) and bayerite (β-Al(OH){sub 3}), as well as the polyoxocations ''Al{sub 13}'' (Al{sub 13}O{sub 4}(OH){sub 24}(H{sub 2}O){sub 12}{sup 7+}) and ''GaAl{sub 12}'' (GaO{sub 4}Al{sub 12}(OH){sub 24}(H{sub 2}O){sub 12}{sup 7+}). These investigations should contribute to a sound understanding of the solution-mineral-interface reactions relevant for the migration of radionuclides (in particular the actinides) in the near and far field of a repository for high-level radioactive waste in deep geological formations, e.g. adsorption and structural incorporation. Batch sorption studies show similar logK{sub d} values for Eu(III) sorption onto corundum and bayerite at low metal ion concentrations ([M(III)] ∝ 7.10{sup -7} M). These similarities can be related to the formation of Al-OH groups on the aluminium oxide surfaces. Comparable logK{sub d} values could be found in earlier investigations for Gd(III) sorbed onto γ-Al{sub 2}O{sub 3}. In agreement with the batch sorption results at trace metal ion concentrations, time resolved laser fluorescence spectroscopy (TRLFS) studies on the interaction of Cm(III) with corundum and bayerite suggest a similar Cm(III) speciation between pH = 3 and 13. Three different surface sorbed Cm(III) species can be distinguished for these mineral phases ([surface..Cm(OH){sub x}(H{sub 2}O){sub 5-x}]{sup 3-x} with x = 0, 1, 2). Comparable TRLFS results can also be found for Cm(III) sorbed on the sapphire (001) single crystal surface and on ''Al{sub 13}'' and ''GaAl{sub 12}''. In the Cm(III)/gibbsite system, spectroscopic results show clear differences in comparison to bayerite, corundum and γ-Al{sub 2}O{sub 3}, e.g. a Cm(III) species of

  19. How to interpret Methylation Sensitive Amplified Polymorphism (MSAP) profiles?

    OpenAIRE

    Fulneček, Jaroslav; Kovařík, Aleš

    2014-01-01

    Background DNA methylation plays a key role in development, contributes to genome stability, and may also respond to external factors supporting adaptation and evolution. To connect different types of stimuli with particular biological processes, identifying genome regions with altered 5-methylcytosine distribution at a genome-wide scale is important. Many researchers are using the simple, reliable, and relatively inexpensive Methylation Sensitive Amplified Polymorphism (MSAP) method that is ...

  20. Diagnostic markers of urothelial cancer based on DNA methylation analysis

    International Nuclear Information System (INIS)

    Chihara, Yoshitomo; Hirao, Yoshihiko; Kanai, Yae; Fujimoto, Hiroyuki; Sugano, Kokichi; Kawashima, Kiyotaka; Liang, Gangning; Jones, Peter A; Fujimoto, Kiyohide; Kuniyasu, Hiroki

    2013-01-01

    Early detection and risk assessment are crucial for treating urothelial cancer (UC), which is characterized by a high recurrence rate, and necessitates frequent and invasive monitoring. We aimed to establish diagnostic markers for UC based on DNA methylation. In this multi-center study, three independent sample sets were prepared. First, DNA methylation levels at CpG loci were measured in the training sets (tumor samples from 91 UC patients, corresponding normal-appearing tissue from these patients, and 12 normal tissues from age-matched bladder cancer-free patients) using the Illumina Golden Gate methylation assay to identify differentially methylated loci. Next, these methylated loci were validated by quantitative DNA methylation by pyrosequencing, using another cohort of tissue samples (Tissue validation set). Lastly, methylation of these markers was analyzed in the independent urine samples (Urine validation set). ROC analysis was performed to evaluate the diagnostic accuracy of these 12 selected markers. Of the 1303 CpG sites, 158 were hyper ethylated and 356 were hypo ethylated in tumor tissues compared to normal tissues. In the panel analysis, 12 loci showed remarkable alterations between tumor and normal samples, with 94.3% sensitivity and 97.8% specificity. Similarly, corresponding normal tissue could be distinguished from normal tissues with 76.0% sensitivity and 100% specificity. Furthermore, the diagnostic accuracy for UC of these markers determined in urine samples was high, with 100% sensitivity and 100% specificity. Based on these preliminary findings, diagnostic markers based on differential DNA methylation at specific loci can be useful for non-invasive and reliable detection of UC and epigenetic field defect