Science.gov

Sample records for acid moiety attached

  1. Lactic acid oligomers (OLAs) as prodrug moieties.

    PubMed

    Kruse, J; Lachmann, B; Lauer, R; Eppacher, S; Noe, C R

    2013-02-01

    In this paper we propose the use of lactic acid oligomers (OLAs) as prodrug moieties. Two synthetic approaches are presented, on the one hand a non selective oligomerisation of lactic acid and on the other hand a block synthesis to tetramers of lactic acid. Dimers of lactic acid were investigated with respect to their plasma stability and their adsorption to albumine. Ibuprofen was chosen as the first drug for OLAylation. The ester 19 of LA(1)-ibuprofen was evaluated with respect to the degradation to human plasma and the adsorption to albumine. All results indicate that lactic acid oligomers are promising prodrug moieties.

  2. Iptycene synthesis: A new method for attaching a 2,3-anthracene moiety to the 9,10-positions of another anthracene moiety - Exceptional conditions for a Lewis acid catalyzed Diels-Alder reaction

    NASA Technical Reports Server (NTRS)

    Chen, Yong-Shing; Hart, Harold

    1989-01-01

    An efficient three-step method for appending a 2,3-anthracene moiety to the 9,10-positions of an existing anthracene moiety is described. The first step uses excess 1,4-anthraquinone (3 equiv) and aluminum chloride (6 equiv) to obtain the anthracene-quinone cycloadduct (omission of the AlCl3 resulted in no adduct). The resulting diketone was reduced to the corresponding diol (excess LiAlH4), which was dehydrated to the arene with phosphorus oxychloride and pyridine. Specific examples include the preparation of heptipycene 8 from pentiptycene 6 (66 percent overall yield) and a similar conversion of 8 to the noniptycene 13 (75 percent overall yield). The methodology led to a markedly improved synthesis of tritriptycene 9 and the first synthesis of undecaiptycene 14.

  3. Lipid modification of proteins in Archaea: attachment of a mevalonic acid-based lipid moiety to the surface-layer glycoprotein of Haloferax volcanii follows protein translocation.

    PubMed Central

    Konrad, Zvia; Eichler, Jerry

    2002-01-01

    Once the newly synthesized surface (S)-layer glycoprotein of the halophilic archaeaon Haloferax volcanii has traversed the plasma membrane, the protein undergoes a membrane-related, Mg(2+)-dependent maturation event, revealed as an increase in the apparent molecular mass and hydrophobicity of the protein. To test whether lipid modification of the S-layer glycoprotein could explain these observations, H. volcanii cells were incubated with a radiolabelled precursor of isoprene, [(3)H]mevalonic acid. In Archaea, isoprenoids serve as the major hydrophobic component of archaeal membrane lipids and have been shown to modify other haloarchaeal S-layer glycoproteins, although little is known of the mechanism, site or purpose of such modification. In the present study we report that the H. volcanii S-layer glycoprotein is modified by a derivative of mevalonic acid and that maturation of the protein was prevented upon treatment with mevinolin (lovastatin), an inhibitor of mevalonic acid biosynthesis. These findings suggest that lipid modification of S-layer glycoproteins is a general property of halophilic archaea and, like S-layer glycoprotein glycosylation, lipid-modification of the S-layer glycoproteins takes place on the external cell surface, i.e. following protein translocation across the membrane. PMID:12069685

  4. Hydroxycinnamic acids are ester-linked directly to glucosyl moieties within the lignan macromolecule from flaxseed hulls.

    PubMed

    Struijs, Karin; Vincken, Jean-Paul; Verhoef, René; Voragen, Alphons G J; Gruppen, Harry

    2008-03-01

    In flaxseed hulls, lignans are present in an oligomeric structure. Secoisolariciresinol diglucoside (SDG), ester-linked to hydroxy-methyl-glutaric acid (HMGA), forms the backbone of this lignan macromolecule. The hydroxycinnamic acids p-coumaric acid glucoside (CouAG) and ferulic acid glucoside (FeAG) are also part of the lignan macromolecule. However, their position and type of linkage are still unknown. The aim of this study was to investigate how CouAG and FeAG are linked within the lignan macromolecule from flaxseed hulls. Fragments of the lignan macromolecule were obtained by partial saponification. After isolation of the fragments by preparative RP-HPLC, several key structures were identified by MS and NMR. Within the lignan macromolecule, CouAG is attached to the C-6 position of a glucosyl moiety of SDG. FeA is linked to the C-2 position of a glucosyl moiety of SDG. FeAG is ester-linked within the lignan macromolecule with its carboxyl group, but it remains unclear whether FeAG links to the C-2 or C-6 position of SDG. Attachment of HMGA to the glucosyl moiety of CouAG or FeAG was not observed. The results clearly show that within the lignan macromolecule, the hydroxycinnamic acids are linked directly via an ester bond to the glucosyl moiety of SDG.

  5. Ice-like encapsulated water by two cholic acid moieties.

    PubMed

    Soto, Victor H; Alvarez, Mercedes; Meijide, Francisco; Trillo, Juan V; Antelo, Alvaro; Jover, Aida; Galantini, L; Tato, José Vázquez

    2012-10-01

    Starting from the structure of ice (in which each water molecule is surrounded by other four water molecules forming a tetrahedron with a value of 4.51Å for the edge O-O distance), and the knowledge that this value also corresponds to the O7-O12 distance of the skeleton of cholic acid, it is hypothesized that two steroid cholic acid moieties, with an appropriate steroid-steroid distance and a belly-to-belly orientation, could encapsulate a single water molecule between them. To check this hypothesis two succinyl derivatives of cholic acid (a monomer and the related head-head dimer in which the succinyl group is the linking bridge) were designed. The expected "ice-like" structure is found in the crystal of the dimer. There is a hydrogen bond synergy between those participating in the "ice-like" structure, and those in which the bridge is involved with the O7-H hydroxy group and the side chain of the steroid.

  6. Attachment of second harmonic-active moiety to molecules for detection of molecules at interfaces

    DOEpatents

    Salafsky, Joshua S.; Eisenthal, Kenneth B.

    2005-10-11

    This invention provides methods of detecting molecules at an interface, which comprise labeling the molecules with a second harmonic-active moiety and detecting the labeled molecules at the interface using a surface selective technique. The invention also provides methods for detecting a molecule in a medium and for determining the orientation of a molecular species within a planar surface using a second harmonic-active moiety and a surface selective technique.

  7. Biotin and Lipoic Acid: Synthesis, Attachment and Regulation

    PubMed Central

    Cronan, John E.

    2014-01-01

    Summary Two vitamins, biotin and lipoic acid, are essential in all three domains of life. Both coenzymes function only when covalently attached to key metabolic enzymes. There they act as “swinging arms” that shuttle intermediates between two active sites (= covalent substrate channeling) of key metabolic enzymes. Although biotin was discovered over 100 years ago and lipoic acid 60 years ago, it was not known how either coenzyme is made until recently. In Escherichia coli the synthetic pathways for both coenzymes have now been worked out for the first time. The late steps of biotin synthesis, those involved in assembling the fused rings, were well-described biochemically years ago, although recent progress has been made on the BioB reaction, the last step of the pathway in which the biotin sulfur moiety is inserted. In contrast, the early steps of biotin synthesis, assembly of the fatty acid-like “arm” of biotin were unknown. It has now been demonstrated that the arm is made by using disguised substrates to gain entry into the fatty acid synthesis pathway followed by removal of the disguise when the proper chain length is attained. The BioC methyltransferase is responsible for introducing the disguise and the BioH esterase for its removal. In contrast to biotin, which is attached to its cognate proteins as a finished molecule, lipoic acid is assembled on its cognate proteins. An octanoyl moiety is transferred from the octanoyl-ACP of fatty acid synthesis to a specific lysine residue of a cognate protein by the LipB octanoyl transferase followed by sulfur insertion at carbons C6 and C8 by the LipA lipoyl synthetase. Assembly on the cognate proteins regulates the amount of lipoic acid synthesized and thus there is no transcriptional control of the synthetic genes. In contrast transcriptional control of the biotin synthetic genes is wielded by a remarkably sophisticated, yet simple, system, exerted through BirA a dual function protein that both represses

  8. Synthesis and biological properties of amino acids and peptides containing a tetrazolyl moiety

    NASA Astrophysics Data System (ADS)

    Popova, E. A.; Trifonov, R. E.

    2015-09-01

    Literature data published mainly in the last 15 years on the synthesis and biological properties of amino acid analogues and derivatives containing tetrazolyl moieties are analyzed. Tetrazolyl analogues and derivatives of amino acids and peptides are shown to be promising for medicinal chemistry. Being polynitrogen heterocyclic systems comprising four endocyclic nitrogen atoms, tetrazoles can behave as acids and bases and form strong hydrogen bonds with proton donors (more rarely, with acceptors). They have high metabolic stability and are able to penetrate biological membranes. The review also considers the synthesis and properties of linear and cyclic peptides based on modified amino acids incorporating a tetrazolyl moiety. A special issue is the discussion of the biological properties of tetrazole-containing amino acids and peptides, which exhibit high biological activity and can be used to design new drugs. The bibliography includes 200 references.

  9. [New synthesis of the anticoagulant pentasaccharide idraparinux and preparation of its analogues containing sulfonic acid moieties].

    PubMed

    Herczeg, Mihály

    2012-01-01

    Two novel synthetic pathways were elaborated for the preparation of idraparinux, a heparin-related fully O-sulfated, O-methylated anticoagulant pentasaccharide. Both methods based upon a [2+3] block synthesis utilizing the same trisaccharide acceptor which was coupled to either a uronic acid disaccharide donor or its nonoxidized precursor. Two bioisosteric sulfonic acid analogues of idraparinux were also prepared, in which two or three primary sulfate esters were replaced by sodium-sulfonatomethyl moieties. The sulfonic acid groups were formed on a monosaccharide level and the obtained carbohydrate sulfonic acid esters were found to be excellent donors and acceptors in the glycosylation reactions. The disulfonic-acid analogue was prepared in a [2+3] block synthesis by using a trisaccharide disulfonic acid as an acceptor and a glucuronide disaccharide as a donor. For the synthesis of the pentasaccharide trisulfonic acid, a more-efficient approach, which involved elongation of the trisaccharide acceptor with a non-oxidized precursor of the glucuronic acid followed by post-glycosidation oxidation at the tetrasaccharide level and a subsequent [1+4] coupling reaction, was elaborated. In vitro evaluation of the anticoagulant activity of the reference compound idraparinux and the new sulfonic acid derivatives revealed that the disulfonate analogue inhibited the blood-coagulation-proteinase factor Xa with outstanding efficacy; however, the introduction of the third sulfonic acid moiety resulted in a notable decrease in the anti-Xa activity.

  10. Higher reactivity of apolipoprotein B-100 and alpha-tocopherol compared to sialic acid moiety of low-density lipoprotein (LDL) in radical reaction.

    PubMed

    Matsukawa, Nao; Nariyama, Yoko; Hashimoto, Ryoko; Kojo, Shosuke

    2003-09-01

    Radical reaction of low-density lipoprotein (LDL) is a key step in atherogenesis and causes both a decrease in the sialic acid moiety and modification of apolipoprotein B-100 (apoB). Although apoB modification (cross-link and fragmentation) increases in atherosclerosis, the change in apoB-bound sialic acid in atherosclerosis is controversial. To elucidate the physiological implications of desialylation of LDL by radical reaction, the reactivity of sialic acid of LDL was compared with that of apoB, which underwent facile fragmentation in radical reactions. ApoB was determined by immunoblot analysis with anti-apoB antiserum, and the sialic acid moiety was measured by blot analysis with a biotin-bound lectin [biotin-SSA from Japanese elderberry (Sambucus sieboldiana)] specific to sialic acid. When human LDL was oxidized with Cu(2+) at 37 degrees C, apoB and apoB-attached sialic acid decreased simultaneously. Comparison of the staining bands with anti-apoB and with biotin-SSA shows that sialic acid moieties still remain on fragmented apoB proteins, indicating that the decrease in sialic acid is much slower than that of apoB fragmentation. In addition, human plasma was oxidized with 400 microM of Cu(2+) at 37 degrees C. Similar analysis indicates that the decrease in sialic acid attached to apoB also results from the fragmentation of apoB. This study indicates that the fragmentation of apoB proceeds at a much faster rate than the decrease in sialic acid content when a free radical reaction is induced in isolated LDL as well as in plasma LDL exposed to Cu(2+)-induced oxidative stress. On the basis of these results, the modification of apoB is much more sensitive than the decrease in sialic acid as an indicator of oxidative stress.

  11. Bifunctional ruthenium(II) hydride complexes with pendant strong Lewis acid moieties: structure, dynamics, and cooperativity.

    PubMed

    Ostapowicz, Thomas G; Merkens, Carina; Hölscher, Markus; Klankermayer, Jürgen; Leitner, Walter

    2013-02-13

    The synthesis of a novel class of bifunctional ruthenium hydride complexes incorporating Lewis acidic BR(2) moieties is reported. Determination of the molecular structures in the solid state and in solution provided evidence for tunable interaction between the two functionalities. Cooperative effects on the reactivity of the complexes were demonstrated including the activation of small Lewis basic molecules by reversible anchoring at the boron center.

  12. Sensitizers containing donor cascade and rhodanine-3-acetic acid moieties for dye-sensitized solar cells

    SciTech Connect

    Wu, Quan-Ping; Zhang, Lu; Liang, Mao; Sun, Zhe; Xue, Song

    2011-01-15

    Three organic dyes with D-{pi}-D-{pi}-A structure based on triarylamine, dimethylarylamine, and rhodanine-3-acetic acid moieties are designed and synthesized. Incorporating thiophene moieties into the system affords sensitizers with high molar extinction coefficients. These dyes were applied into nanocrystalline TiO{sub 2} dye-sensitized solar cells through standard operations. For a typical device the maximal monochromatic incident photon-to-current conversion efficiency (IPCE) can reach 73%, with a short-circuit photocurrent density (J{sub sc}) of 7.3 mA/cm{sup 2}, an open-circuit voltage (V{sub oc}) of 636 mV, and a fill factor (ff) of 0.61, corresponding to an overall conversion efficiency ({eta}) of 2.86%. (author)

  13. Structure-activity relationship of ochratoxin A and synthesized derivatives: importance of amino acid and halogen moiety for cytotoxicity.

    PubMed

    Rottkord, Ulrike; Röhl, Christopher; Ferse, Ines; Schulz, Marie-Christin; Rückschloss, Uwe; Gekle, Michael; Schwerdt, Gerald; Humpf, Hans-Ulrich

    2017-03-01

    The enigma why the mycotoxin ochratoxin A (OTA) impairs cell and organ function is still not solved. However, an interaction with target molecules is a prerequisite for any observed adverse effect. This interaction depends on characteristics of the target molecule as well as on the OTA molecule itself. OTA has different structural moieties which may be relevant for these interrelations including a halogen (chlorine) and an amino acid group (phenylalanine). To test their importance for the impact of OTA, detailed structure-activity studies with various OTA derivatives were performed. For this, 23 OTA derivatives were available, which were modified by either an exchange of the halogen moiety against another halogen (fluorine, iodine or bromine) or by the amino acid moiety against another one (tyrosine or alanine) or a combination of both. Additionally, the configuration of the 3R carbon atom was changed to 3S. These derivatives were tested in human renal cells for their ability to induce cell death (cytotoxicity, apoptosis, necrosis), their impact on collagen protein secretion and for their influence on gene expression. It turned out that the substitution of the amino acid moiety against tyrosine or alanine almost completely prevented the adverse effects of OTA. The exchange of the halogen moiety had minor effects and the inversion of the stereochemistry at C3 did not prevent the effects of OTA. Therefore, we conclude that the amino acid moiety of OTA is indispensable for the interaction of OTA with its target molecules.

  14. Molecular Anchors for Self-Assembled Monolayers on ZnO: A Direct Comparison of the Thiol and Phosphic Acid Moieties

    SciTech Connect

    Perkins, C. L.

    2009-01-01

    Two of the most promising schemes for attaching organic molecules to metal oxides are based on the chemistry of the thiol and phosphonic acid moieties. We have made a direct comparison of the efficacy of these two molecular anchors on zinc oxide by comparing the chemical and physical properties of n-hexane derivatives of both. The surface properties of polycrystalline ZnO thin films and ZnO(000)-O crystals modified with 1-hexanethiol and 1-hexanephosphonic acid were examined with a novel quartz crystal microbalance (QCM)-based flow cell reactor, angle-resolved and temperature-dependent photoelectron spectroscopy, and contact angle measurements. A means of using ammonium chloride as a probe of molecule-ZnO interactions is introduced and used to ascertain the relative quality of self-assembled monolayers (SAMs) based on thiols and phosphonic acids. QCM data shows that a phosphonic acid-anchored alkyl chain only six carbons long can provide significant corrosion protection for ZnO against Bronsted acids, reducing the etch rate relative to the bare ZnO surface by a factor of more than nine. In contrast, we find that monolayers from the analogous molecule hexanethiol are more defective as revealed by their higher ionic permeability and lower hydrophobicity. Substrate attenuation X-ray photoelectron spectroscopy (XPS) experiments were used to determine the thickness of SAMs formed by the two hexane derivatives and it was found that SAMs from phosphonic acids were approximately twice as thick as those formed by hexanethiol. The thermal stability of the two linking groups was also explored and we find that previous claims of highly stable alkanethiolate monolayers on ZnO are suspect. Taken as a whole, our results indicate that the phosphonic acid moiety is preferred over thiols for the attachment of short alkyl groups to ZnO.

  15. A Highly Potent and Selective Caspase 1 Inhibitor that Utilizes a Key 3-Cyanopropanoic Acid Moiety

    PubMed Central

    Boxer, Matthew B.; Quinn, Amy M.; Shen, Min; Jadhav, Ajit; Leister, William; Simeonov, Anton; Auld, Douglas S.; Thomas, Craig J.

    2011-01-01

    Herein we examine the potential of a nitrile-containing proprionic acid moiety as an electrophile for covalent attack by the active site cysteine residue of caspase 1. The syntheses of several cyanopropanate containing small molecules based upon the optimized peptidic scaffold of the prodrug VX-765 were accomplished and found to be potent inhibitors of caspase 1 (IC50s ≤ 1 nM). Examination of these novel small molecules versus a caspase panel demonstrated an impressive degree of selectivity for caspase 1 inhibition. Assessment of hydrolytic stability and selected ADME properties highlighted these agents as potentially useful tools for studying caspase 1 down-regulation in various settings including in vivo analyses. PMID:20229566

  16. Formation of chloroacetic acids from soil, humic acid and phenolic moieties.

    PubMed

    Fahimi, I J; Keppler, F; Schöler, H F

    2003-07-01

    The mechanism of formation of chloroacetates, which are important toxic environmental substances, has been controversial. Whereas the anthropogenic production has been well established, a natural formation has also been suggested. In this study the natural formation of chloroacetic acids from soil, as well as from humic material which is present in soil and from phenolic model substances has been investigated. It is shown that chloroacetates are formed from humic material with a linear relationship between the amount of humic acid used and chloroacetates found. More dichloroacetate (DCA) than trichloroacetate (TCA) is produced. The addition of Fe(2+), Fe(3+) and H(2)O(2) leads to an increased yield. NaCl was added as a source of chloride. We further examined the relationship between the structure and reactivity of phenolic substances, which can be considered as monomeric units of humic acids. Ethoxyphenol with built-in ethyl groups forms large amounts of DCA and TCA. The experiments with phenoxyacetic acid yielded large amounts of monochloroacetate (MCA). With other phenolic substances a ring cleavage was observed. Our investigations indicate that chloroacetates are formed abiotically from humic material and soils in addition to their known biotic mode of formation.

  17. Influences of fatty acid moiety and esterification of polyglycerol fatty acid esters on the crystallization of palm mid fraction in oil-in-water emulsion.

    PubMed

    Sakamoto, Mitsuhiro; Ohba, Azusa; Kuriyama, Juhei; Maruo, Kouichi; Ueno, Satoru; Sato, Kiyotaka

    2004-08-15

    We examined the crystallization of palm mid fraction (PMF) in oil-in-water (O/W) emulsion, after adding polyglycerol fatty acid esters (PGFEs). We employed ultrasonic velocity measurements and DSC techniques, with special emphases on the influences of fatty acid moiety and esterification of PGFE. Twelve types of PGFEs were examined as additives. PGFEs have a large hydrophilic moiety composed of 10 glycerol molecules to which palmitic, stearic and behenic acids were esterified as the fatty acid moiety with different degrees of esterification. Crystallization temperature (T(c)) of PMF remarkably increased with increasing concentrations of the PGFEs as the chain length of the fatty acid moiety increased, and the PGFE became more hydrophobic in accordance with increasing degree of esterification. We observed that the heterogeneous nucleation of PMF in the O/W emulsion was activated at the oil-water interface, where the template effect of very hydrophobic long saturated fatty acid chains of the PGFE might play the main role of heterogeneous nucleation.

  18. Antimicrobial effect of para-alkoxyphenylcarbamic acid esters containing substituted N-phenylpiperazine moiety

    PubMed Central

    Malík, Ivan; Bukovský, Marián; Andriamainty, Fils; Gališinová, Jana

    2013-01-01

    In current research, nine basic esters of para-alkoxyphenylcarbamic acid with incorporated 4-(4-fluoro-/3-trifluoromethylphenyl)piperazin-1-yl fragment, 6i–6m and 8f–8i, were screened for their in vitro antimicrobial activity against Candida albicans, Staphylococcus aureus and Escherichia coli, respectively. Taking into account the minimum inhibitory concentration assay (MIC), as the most active against given yeast was evaluated 8i (MIC = 0.20 mg/mL), the most lipophilic structure containing para-butoxy and trifluoromethyl substituents. Investigating the efficiency of the compounds bearing only a single atom of fluorine and appropriate para-alkoxy side chain against Candida albicans, the cut-off effect was observed. From evaluated homological series, the maximum of the effectiveness was noticed for the stucture 6 k (MIC = 0.39 mg/mL), containing para-propoxy group attached to phenylcarbamoyloxy fragment, beyond which the compounds ceased to be active. On the contrary, all the tested molecules were against Staphylococcus aureus and Escherichia coli (MICs > 1.00 mg/mL) practically inactive. PMID:24294237

  19. Dissociative attachment reactions of electrons with strong acid molecules

    SciTech Connect

    Adams, N.G.; Smith, D.; Viggiano, A.A.; Paulson, J.F.; Henchman, M.J.

    1986-06-15

    Using the flowing afterglow/Langmuir probe (FALP) technique, we have determined (at variously 300 and 570 K) the dissociative attachment coefficients ..beta.. for the reactions of electrons with the common acids HNO/sub 3/ (producing NO/sup -//sub 2/) and H/sub 2/SO/sub 4/ (HSO/sup -//sub 4/), the superacids FSO/sub 3/H (FSO/sup -//sub 3/), CF/sub 3/SO/sub 3/H (CF/sub 3/SO/sup -//sub 3/), ClSO/sub 3/H (ClSO/sup -//sub 3/,Cl/sup -/), the acid anhydride (CF/sub 3/SO/sub 2/)/sub 2/O (CF/sub 3/SO/sup -//sub 3/), and the halogen halides HBr (Br/sup -/) and HI (I/sup -/). The anions formed in the reactions are those given in the parentheses. The reactions with HF and HCl were investigated, but did not occur at a measurable rate since they are very endothermic. Dissociative attachment is rapid for the common acids, the superacids, and the anhydride, the measured ..beta.. being appreciable fractions of the theoretical maximum ..beta.. for such reactions, ..beta../sub max/. The HI reaction is very fast ( ..beta..approx...beta../sub max/) but the HBr reaction occurs much more slowly because it is significantly endothermic. The data indicate that the extreme acidity of the (Bronsted-type) superacids has its equivalence in the very efficient gas-phase dissociative attachment which these species undergo when reacting with free electrons. The anions of the superacids generated in these reactions, notably FSO/sup -//sub 3/ and CF/sub 3/SO/sup -//sub 3/, are very stable (unreactive) implying exceptionally large electron affinities for the FSO/sub 3/ and CF/sub 3/SO/sub 3/ radicals.

  20. A Formal Approach to Xylosmin and Flacourtosides E and F: Chemoenzymatic Total Synthesis of the Hydroxylated Cyclohexenone Carboxylic Acid Moiety of Xylosmin.

    PubMed

    Ghavre, Mukund; Froese, Jordan; Murphy, Brennan; Simionescu, Razvan; Hudlicky, Tomas

    2017-02-10

    The hydroxylated cyclohexenone carboxylic acid moiety of xylosmin was synthesized in eight steps from benzoic acid. The key steps in the synthesis involved the enzymatic dihydroxylation of benzoic acid by the whole cell fermentation with Ralstonia eutrophus B9, and Henbest epoxidation. Early attempts led to the synthesis of a C6 epimer of the methyl ester of the hydroxylated cyclohexenone carboxylic acid moiety. The absolute stereochemistry of an advanced intermediate was confirmed by X-ray crystallography. Complete characterization of the previously reported but not fully characterized hydroxylated cyclohexenone carboxylic acid is provided.

  1. Acidity constant determination of novel drug precursor benzothiazolon derivatives including acyl and piperazine moieties

    NASA Astrophysics Data System (ADS)

    Sıdır, İsa; Gülseven Sıdır, Yadigar; Berber, Halil

    2013-07-01

    In this study, protonation and deprotonation behaviors of eight new drug precursor benzothiazolon derivatives in all of acidic and basic scale (super acidic, pH, super basic regions) are analyzed by using UV-visible spectrophotometric technique. Acidity constants (pKa), elucidation of the structure and protonation mechanisms of the studied molecules are obtained. Substituent effect on acidity constant values is discussed. These molecules are protonated from oxygen atom of acetamide group in the keto form. The protonation is found to be considerably contributed by the keto form.

  2. Photodegradation mechanism of nonsteroidal anti-inflammatory drugs containing thiophene moieties: suprofen and tiaprofenic acid.

    PubMed

    Musa, Klefah A K; Eriksson, Leif A

    2009-08-13

    The photodegradation of nonsteroid anti-inflammatory drugs suprofen, 2-[4-(2-thienoyl)phenyl]propionic acid, and tiaprofenic acid, 2-(5-benzoyl-2-thienyl)propanoic acid, is studied by means of density functional theory. Besides the redox properties of the neutral species, we report on absorption spectra and degradation pathways involving excitation, intersystem crossing to the T(1) state, and spontaneous decarboxylation of the deprotonated species of each drug. The energetics and properties of the suprofen and tiaprofenic acid systems are found to be very similar to those of the highly photolabile benzyl analogue ketoprofen. Mechanisms leading to the formation of a closed-shell decarboxylated ethyl species, as well as peroxyl radicals capable of initiating lipid peroxidation reactions, are discussed.

  3. Peptidyl prolyl isomerase Pin1-inhibitory activity of D-glutamic and D-aspartic acid derivatives bearing a cyclic aliphatic amine moiety.

    PubMed

    Nakagawa, Hidehiko; Seike, Suguru; Sugimoto, Masatoshi; Ieda, Naoya; Kawaguchi, Mitsuyasu; Suzuki, Takayoshi; Miyata, Naoki

    2015-12-01

    Pin1 is a peptidyl prolyl isomerase that specifically catalyzes cis-trans isomerization of phosphorylated Thr/Ser-Pro peptide bonds in substrate proteins and peptides. Pin1 is involved in many important cellular processes, including cancer progression, so it is a potential target of cancer therapy. We designed and synthesized a novel series of Pin1 inhibitors based on a glutamic acid or aspartic acid scaffold bearing an aromatic moiety to provide a hydrophobic surface and a cyclic aliphatic amine moiety with affinity for the proline-binding site of Pin1. Glutamic acid derivatives bearing cycloalkylamino and phenylthiazole groups showed potent Pin1-inhibitory activity comparable with that of known inhibitor VER-1. The results indicate that steric interaction of the cyclic alkyl amine moiety with binding site residues plays a key role in enhancing Pin1-inhibitory activity.

  4. Formation of an 8-hydroxyguanine moiety in deoxyribonucleic acid on gamma-irradiation in aqueous solution

    SciTech Connect

    Dizdaroglu, M.

    1985-07-30

    Isolation and characterization of a novel radiation-induced product, i.e., the 8-hydroxyguanine residue, produced in deoxyribonucleic acid (DNA), 2'-deoxyguanosine, and 2'-deoxyguanosine 5'-monophosphate by gamma-irradiation in aqueous solution, are described. For this purpose, gamma-irradiated DNA was first hydrolyzed with a mixture of four enzymes, i.e., DNase I, spleen and snake venom exonucleases, and alkaline phosphatase. Analysis of the resulting mixture by capillary gas chromatography-mass spectrometry after trimethylsilylation revealed the presence of a product, which was identified as 8-hydroxy-2'-deoxyguanosine on the basis of the typical fragment ions of its trimethylsilyl (Me3Si) derivative. This product was then isolated by using reversed-phase high-performance liquid chromatography. The UV and proton nuclear magnetic resonance spectra taken from the isolated product confirmed the structure suggested by the mass spectrum of its Me3Si derivative. The yield of 8-hydroxyguanine was also measured. Its mechanism of formation is believed to involve OH radical addition to the C-8 position of guanine followed by oxidation of the radical adduct.

  5. Enzymatic Depletion of the Polysialic Acid Moiety Associated with the Neural Cell Adhesion Molecule Inhibits Antidepressant Efficacy.

    PubMed

    Wainwright, Steven R; Barha, Cindy K; Hamson, Dwayne K; Epp, Jonathan R; Chow, Carmen; Lieblich, Stephanie E; Rutishauser, Urs; Galea, Liisa Am

    2016-05-01

    Antidepressant drugs are too often ineffective, the exact mechanism of efficacy is still ambiguous, and there has been a paucity of novel targets for pharmacotherapy. In an attempt to understand the pathogenesis of depression and subsequently develop more efficacious antidepressant drugs, multiple theories have been proposed, including the modulation of neurotransmission, the upregulation of neurogenesis and neurotrophic factors, normalizing hypothalamic-pituitary-adrenal reactivity, and the reduction of neuroinflammation; all of which have supporting lines of evidence. Therefore, an ideal molecular target for novel pharmaceutical intervention would function at the confluence of these theories. The polysialylated form of the neural cell adhesion molecule (PSA-NCAM) functions broadly, serving to mediate synaptic plasticity, neurogenesis, neurotrophic factor signaling, and inflammatory signaling throughout the brain; all of which are associated with the pathophysiology and treatment of depression. Moreover, the expression of PSA-NCAM is reduced by depression, and conversely enhanced by antidepressant treatment, particularly within the hippocampus. Here we demonstrate that selectively cleaving the polysialic acid moiety, using the bacteriophage-derived enzyme endoneuraminidase N, completely inhibits the antidepressant efficacy of the selective-serotonin reuptake inhibitor fluoxetine (FLX) in a chronic unpredictable stress model of depression. We also observe a corresponding attenuation of FLX-induced hippocampal neuroplasticity, including decreased hippocampal neurogenesis, synaptic density, and neural activation. These data indicate that PSA-NCAM-mediated neuroplasticity is necessary for antidepressant action; therefore PSA-NCAM represents an interesting, and novel, target for pharmacotherapy.

  6. Enzymatic synthesis of 2'-modified nucleic acids: identification of important phosphate and ribose moieties in RNase P substrates.

    PubMed Central

    Conrad, F; Hanne, A; Gaur, R K; Krupp, G

    1995-01-01

    For the first time mosaic nucleic acids composed of 50% RNA and 50% DNA can be obtained as transcripts with T7 RNA polymerase. Two NTPs could be replaced simultaneously in a transcription reaction. This means more than 40 deoxynucleotides were inserted in one transcript. Previously, a maximum of two deoxynucleotides could be incorporated and 2'-O-methyl-NTPs were not substrates at all. We obtained reasonable transcript yields with a maximal level of 99% 2'-O-methyl-NTPs, and the products contained up to 58% 2'-O-methylnucleotides at more than 20 positions. Sequence-specific nucleotide incorporation was monitored by sequence ladders (partial alkali or iodine cleavage). No base misincorporations were detected with 100% dGTP, dCTP and dTTP, and with partial incorporation of dATP alpha S, 2'-O-methyl-GTP alpha S and 2'-O-methyl-CTP alpha S, whereas they were found with dATP, 2'-O-methyl-ATP alpha S and 2'-O-methyl-UTP alpha S. Quantitative data allow predetermined modification levels of partially modified transcripts. Highly modified transcripts can be used for structural and functional studies, in modification interference approaches and for in vitro evolution procedures. Modification interference studies revealed a small number of important phosphate and ribose moieties in RNase P substrates. The conversion of T7 RNA polymerase to a DNA polymerase extends the observation that there is no absolute distinction between RNA and DNA polymerases. Accordingly, an adapted concept of a primordial RNA world is presented. Images PMID:7541130

  7. Bifunctional cyclam-based ligands with phosphorus acid pendant moieties for radiocopper separation: thermodynamic and kinetic studies.

    PubMed

    Paúrová, Monika; Havlíčková, Jana; Pospíšilová, Aneta; Vetrík, Miroslav; Císařová, Ivana; Stephan, Holger; Pietzsch, Hans-Jürgen; Hrubý, Martin; Hermann, Petr; Kotek, Jan

    2015-03-16

    Two macrocyclic ligands based on cyclam with trans-disposed N-methyl and N-(4-aminobenzyl) substituents as well as two methylphosphinic (H2L1) or methylphosphonic (H4L2) acid pendant arms were synthesised and investigated in solution. The ligands form stable complexes with transition metal ions. Both ligands show high thermodynamic selectivity for divalent copper over nickel(II) and zinc(II)-K(CuL) is larger than K(Ni/ZnL) by about seven orders of magnitude. Complexation is significantly faster for the phosphonate ligand H4L2, probably due to the stronger coordination ability of the more basic phosphonate groups, which efficiently bind the metal ion in an "out-of-cage" complex and thus accelerate its "in-cage" binding. The rate of Cu(II) complexation by the phosphinate ligand H2L1 is comparable to that of cyclam itself and its derivatives with non-coordinating substituents. Acid-assisted decomplexation of the copper(II) complexes is relatively fast (τ1/2 = 44 and 42 s in 1 M aq. HClO4 at 25 °C for H2L1 and H4L2, respectively). This combination of properties is convenient for selective copper removal/purification. Thus, the title ligands were employed in the preparation of ion-selective resins for radiocopper(II) separation. Glycidyl methacrylate copolymer beads were modified with the ligands through a diazotisation reaction. The separation ability of the modified polymers was tested with cold copper(II) and non-carrier-added (64)Cu in the presence of a large excess of both nickel(II) and zinc(II). The experiments exhibited high overall separation efficiency leading to 60-70% recovery of radiocopper with high selectivity over the other metal ions, which were originally present in 900-fold molar excess. The results showed that chelating resins with properly tuned selectivity of their complexing moieties can be employed for radiocopper separation.

  8. Methylation of acidic moieties in poly(methyl methacrylate-co-methacrylic acid) copolymers for end-group characterization by tandem mass spectrometry.

    PubMed

    Giordanengo, Rémi; Viel, Stéphane; Hidalgo, Manuel; Allard-Breton, Béatrice; Thévand, André; Charles, Laurence

    2010-07-30

    The complete structural characterization of a copolymer composed of methacrylic acid (MAA) and methyl methacrylate (MMA) units was achieved using tandem mass spectrometry. In a first step, collision-induced dissociation (CID) of sodiated MAA-MMA co-oligomers allowed us to determine the co-monomeric composition, the random nature of the copolymer and the sum of the end-group masses. However, dissociation reactions of MAA-based molecules mainly involve the acidic pendant groups, precluding individual characterization of the end groups. Therefore, methylation of all the acrylic acid moieties was performed to transform the MAA-MMA copolymer into a PMMA homopolymer, for which CID mainly proceeds via backbone cleavages. Using trimethylsilyldiazomethane as a derivatization agent, this methylation reaction was shown to be complete without affecting the end groups. Using fragmentation rules established for PMMA polymers together with accurate mass measurements of the product ions and knowledge of reagents used for the studied copolymer synthesis, a structure could be proposed for both end groups and it was found to be consistent with signals obtained in nuclear magnetic resonance spectra.

  9. The effect of albumin on podocytes: The role of the fatty acid moiety and the potential role of CD36 scavenger receptor

    SciTech Connect

    Pawluczyk, I.Z.A.; Pervez, A.; Ghaderi Najafabadi, M.; Saleem, M.A.; Topham, P.S.

    2014-08-15

    Evidence is emerging that podocytes are able to endocytose proteins such as albumin using kinetics consistent with a receptor-mediated process. To date the role of the fatty acid moiety on albumin uptake kinetics has not been delineated and the receptor responsible for uptake is yet to be identified. Albumin uptake studies were carried out on cultured human podocytes exposed to FITC-labelled human serum albumin either carrying fatty acids (HSA{sub +FA}) or depleted of them (HSA{sub −FA}). Receptor-mediated endocytosis of FITC-HSA{sub +FA} over 60 min was 5 times greater than that of FITC-HSA{sub −FA}. 24 h exposure of podocytes to albumin up-regulated nephrin expression and induced the activation of caspase-3. These effects were more pronounced in response to HSA{sub −FA.} Individually, anti-CD36 antibodies had no effect upon endocytosis of FITC-HSA. However, a cocktail of 2 antibodies reduced uptake by nearly 50%. Albumin endocytosis was enhanced in the presence of the CD36 specific inhibitor sulfo-N-succinimidyl oleate (SSO) while knock-down of CD36 using CD36siRNA had no effect on uptake. These data suggest that receptor-mediated endocytosis of albumin by podocytes is regulated by the fatty acid moiety, although, some of the detrimental effects are induced independently of it. CD36 does not play a direct role in the uptake of albumin. - Highlights: • The fatty acid moiety is essential for receptor mediated endocytosis of albumin. • Fatty acid depleted albumin is more pathogenic to podocytes. • CD36 is not directly involved in albumin uptake by podocytes.

  10. Thermal-driven attachment of gold nanoparticles prepared with ascorbic acid onto indium tin oxide surfaces

    NASA Astrophysics Data System (ADS)

    Aziz, Md. Abdul; Oyama, Munetaka

    2013-05-01

    Thermal-driven attachment of gold nanoparticles (AuNPs), of which size was less than 50 nm, onto the surfaces of indium tin oxide (ITO) is reported as a new phenomenon. This was permitted by preparing AuNPs via the reduction of hydrogen tetrachloroaurate (HAuCl4) with ascorbic acid (AA). While the AuNPs prepared via the AA reduction sparsely attached on the surface of ITO even at room temperature, a heat-up treatment at ca. 75 °C caused denser attachment of AuNPs on ITO surfaces. The attached density and the homogeneity after the thermal treatment were better than those of AuNP/ITO prepared using 3-aminopropyl-trimethoxysilane linker molecules. The denser attachment was observed similarly both by the immersion of ITO samples after the preparations of AuNPs by AA and by the in situ preparation of AuNPs with AA together with ITO samples. Thus, it is considered that the thermal-driven attachment of AuNPs would occur after the formation of AuNPs in the aqueous solutions, not via the growth of AuNPs on ITO surfaces. The preparation of AuNPs with AA would be a key for the thermal-driven attachment because the same attachments were not observed for AuNPs prepared with citrate ions or commercially available tannic acid-capped AuNPs.

  11. Thermodynamic Analysis of the Selectivity Enhancement Obtained by Using Smart Hydrogels That Are Zwitterionic When Detecting Glucose With Boronic Acid Moieties

    PubMed Central

    Horkay, F.; Cho, S. H.; Tathireddy, P.; Rieth, L.; Solzbacher, F.; Magda, J.

    2011-01-01

    Because the boronic acid moiety reversibly binds to sugar molecules and has low cytotoxicity, boronic acid-containing hydrogels are being used in a variety of implantable glucose sensors under development, including sensors based on optical, fluorescence, and swelling pressure measurements. However, some method of glucose selectivity enhancement is often necessary, because isolated boronic acid molecules have a binding constant with glucose that is some forty times smaller than their binding constant with fructose, the second most abundant sugar in the human body. In many cases, glucose selectivity enhancement is obtained by incorporating pendant tertiary amines into the hydrogel network, thereby giving rise to a hydrogel that is zwitterionic at physiological pH. However, the mechanism by which incorporation of tertiary amines confers selectivity enhancement is poorly understood. In order to clarify this mechanism, we use the osmotic deswelling technique to compare the thermodynamic interactions of glucose and fructose with a zwitterionic smart hydrogel containing boronic acid moieties. We also investigate the change in the structure of the hydrogel that occurs when it binds to glucose or to fructose using the technique of small angle neutron scattering. PMID:22190765

  12. Gold-Catalyzed Highly Regioselective Oxidation of C-C Triple Bonds Without Acid Additives: Propargyl Moieties as Masked α,β-Unsaturated Carbonyls

    PubMed Central

    Lu, Biao; Li, Chaoqun; Zhang, Liming

    2010-01-01

    Gold-catalyzed intermolecular oxidations of internal alkynes have been achieved with high regioselectivities using 8-alkylqinoline N-oxides as oxidants and in the absence of acid additives. Synthetically versatile α,β-unsaturated carbonyls are obtained in good to excellent yields and with excellent E-selectivities. A range of functional groups such as THP, MOMO, N3, OTBS, and N-Boc are tolerated. This reaction allows to mask α,β-unsaturated carbonyls as propargyl moieties, thus offering a practical solution to issues of functional group compatibility with α,β-unsaturated carbonyls, likely encountered in syntheses of complex structures. PMID:20853846

  13. Synthesis and hybridization property of a boat-shaped pyranosyl nucleic acid containing an exocyclic methylene group in the sugar moiety.

    PubMed

    Mori, Kazuto; Kodama, Tetsuya; Obika, Satoshi

    2015-01-01

    A boat-shaped pyranosyl nucleic acid (BsNA) having an exocyclic methylene group in the sugar moiety was synthesized to investigate the possibility that the axial H3' of original BsNA is the cause of its duplex destabilization. The synthesized BsNA analog was chemically stable against various nucleophiles. From the thermal stability of duplex oligonucleotides including the BsNA analog, it was found that the duplex-forming ability can be sensitive to the size of functional groups at the 3'-position.

  14. Dynamics of Low Energy Electron Attachment to Formic Acid

    SciTech Connect

    Rescigno, Thomas N.; Trevisan, Cynthia S.; Orel, Ann E.

    2006-04-03

    Low-energy electrons (<2 eV) can fragment gas phaseformic acid (HCOOH) molecules through resonant dissociative attachmentprocesses. Recent experiments have shown that the principal reactionproducts of such collisions are formate ions (HCOO-) and hydrogen atoms.Using first-principles electron scattering calculations, we haveidentified the responsible negative ion state as a transient \\pi* anion.Symmetry considerations dictate that the associated dissociation dynamicsare intrinsically polyatomic: a second anion surface, connected to thefirst by a conical intersection, is involved in the dynamics and thetransient anion must necessarily deform to non-planar geometries beforeit can dissociate to the observed stable products.

  15. Free-radical-induced formation of an 8,5'-cyclo-2'-deoxyguanosine moiety in deoxyribonucleic acid.

    PubMed Central

    Dizdaroglu, M

    1986-01-01

    Isolation and identification of a novel .OH-induced product, namely an 8,5'-cyclo-2'-deoxyguanosine moiety, in DNA and 2'-deoxyguanosine are described. .OH radicals were generated in dilute aqueous solutions by gamma-irradiation. Analyses of 2'-deoxyguanosine and enzymic hydrolysates of DNA by gas chromatography-mass spectrometry (g.c.-m.s.) after trimethylsilylation showed the presence of 8,5-cyclo-2'-deoxyguanosine on the basis of its fragment ions. This product was isolated by h.p.l.c. Its u.v. and n.m.r. spectra taken were in agreement with the structure suggested by its mass spectrum. Exact masses of the typical ions from the mass spectrum of the trimethylsilyl derivative of this product were measured by high-resolution m.s. The values found were in excellent agreement with the theoretical mass derived from the suggested fragmentation patterns. Both (5'R)- and (5'S)-epimers of 8,5'-cyclo-2'-deoxyguanosine were observed. These two diastereomers were separated from each other by g.c. as well as by h.p.l.c. The assignment of the epimers was accomplished on the basis of the n.m.r. data. The formation of 8,5'-cyclo-2'-deoxyguanosine was suppressed by the presence of O2 in the solutions. The use of g.c.-m.s. with the selected-ion monitoring technique facilitated the detection of 8,5'-cyclo-2'-deoxyguanosine in DNA at radiation doses as low as 1 Gy. Its mechanism of formation probably involves hydrogen atom abstraction by .OH radicals from the C-5' of the 2'-deoxyguanosine moiety followed by intramolecular cyclization with the formation of a covalent bond between the C-5' and C-8 and subsequent oxidation of the resulting N-7-centred radical. PMID:3800936

  16. Impacts of hydrophilic colanic acid on bacterial attachment to microfiltration membranes and subsequent membrane biofouling.

    PubMed

    Yoshida, Keitaro; Tashiro, Yosuke; May, Thithiwat; Okabe, Satoshi

    2015-06-01

    In order to examine the interactions between physicochemical properties of specific extracellular polymeric substances (EPS) and membrane biofouling, we investigated the impacts of hydrophilic colanic acid, as a model extracellular polysaccharide component, on initial bacterial attachment to different microfiltration (MF) membranes and membrane biofouling by using Escherichia coli strains producing different amounts of colanic acid. In a newly designed microtiter plate assay, the bacterial attachment by an E. coli strain RcsF(+), which produces massive amounts of colanic acid, decreased only to a hydrophobic membrane because the colanic acid made cell surfaces more hydrophilic, resulting in low cell attachment to hydrophobic membranes. The bench-scale cross-flow filtration tests followed by filtration resistance measurement revealed that RcsF(+) caused severe irreversible membrane fouling (i.e., pore-clogging), whereas less extracellular polysaccharide-producing strains caused moderate but reversible fouling to all membranes used in this study. Further cross-flow filtration tests indicated that colanic acid liberated in the bulk phase could rapidly penetrate pre-accumulated biomass layers (i.e., biofilms) and then directly clogged membrane pores. These results indicate that colanic acid, a hydrophilic extracellular polysaccharide, and possible polysaccharides with similar characteristics with colanic acid are considered as a major cause of severe irreversible membrane fouling (i.e., pore-clogging) regardless of biofilm formation (dynamic membrane).

  17. Attached and Unattached Bacterial Communities in a 120-Meter Corehole in an Acidic, Crystalline Rock Aquifer

    PubMed Central

    Lehman, R. Michael; Roberto, Francisco F.; Earley, Drummond; Bruhn, Debby F.; Brink, Susan E.; O'Connell, Sean P.; Delwiche, Mark E.; Colwell, Frederick S.

    2001-01-01

    The bacteria colonizing geologic core sections (attached) were contrasted with those found suspended in the groundwater (unattached) by examining the microbiology of 16 depth-paired core and groundwater samples using a suite of culture-independent and culture-dependent analyses. One hundred twenty-two meters was continuously cored from a buried chalcopyrite ore hosted in a biotite-quartz-monzonite porphyry at the Mineral Park Mine near Kingman, Ariz. Every fourth 1.5-m core was acquired using microbiologically defensible methods, and these core sections were aseptically processed for characterization of the attached bacteria. Groundwater samples containing unattached bacteria were collected from the uncased corehole at depth intervals corresponding to the individual cores using an inflatable straddle packer sampler. The groundwater was acidic (pH 2.8 to 5.0), with low levels of dissolved oxygen and high concentrations of sulfate and metals, including ferrous iron. Total numbers of attached cells were less than 105 cells g of core material−1 while unattached cells numbered about 105 cells ml of groundwater−1. Attached and unattached acidophilic heterotrophs were observed throughout the depth profile. In contrast, acidophilic chemolithotrophs were not found attached to the rock but were commonly observed in the groundwater. Attached communities were composed of low numbers (<40 CFU g−1) of neutrophilic heterotrophs that exhibited a high degree of morphologic diversity, while unattached communities contained higher numbers (ca. 103 CFU ml−1) of neutrophilic heterotrophs of limited diversity. Sulfate-reducing bacteria were restricted to the deepest samples of both core and groundwater. 16S ribosomal DNA sequence analysis of attached, acidophilic isolates indicated that organisms closely related to heterotrophic, acidophilic mesophiles such as Acidiphilium organovorum and, surprisingly, to the moderately thermophilic Alicyclobacillus acidocaldarius were present

  18. Effect of monolaurin and lactic acid on Listeria monocytogenes attached to catfish fillets.

    PubMed

    Verhaegh, E G; Marshall, D L; Oh, D H

    1996-04-01

    The purpose of this study was to determine the effects of monolaurin and lactic acid, singly or combined, on Listeria monocytogenes attached to catfish fillets. Skinless catfish fillets were inoculated with L. monocytogenes and dip treated in monolaurin and/or lactic acid solution for various time periods. Results showed that monolaurin up to 400 micrograms/ml had no influence on counts. Conversely, lactic acid-treated fillets had reduced counts compared to controls. Dipping in 0.85, 1.70, or 2.55% lactic acid for 30 min reduced counts by 0.9, 1.4, or 1.3 logs, respectively. Extending the dipping time to 60 min resulted in little additional decrease in counts. Combining monolaurin with lactic acid yielded results similar to lactic acid alone. Hence, population reduction ability resides with lactic acid and not monolaurin.

  19. The macroscopic rate of nucleic acid translocation by hepatitis C virus helicase NS3h is dependent on both sugar and base moieties.

    PubMed

    Khaki, Ali R; Field, Cassandra; Malik, Shuja; Niedziela-Majka, Anita; Leavitt, Stephanie A; Wang, Ruth; Hung, Magdeleine; Sakowicz, Roman; Brendza, Katherine M; Fischer, Christopher J

    2010-07-16

    The nonstructural protein 3 helicase (NS3h) of hepatitis C virus is a 3'-to-5' superfamily 2 RNA and DNA helicase that is essential for the replication of hepatitis C virus. We have examined the kinetic mechanism of the translocation of NS3h along single-stranded nucleic acid with bases uridylate (rU), deoxyuridylate (dU), and deoxythymidylate (dT), and have found that the macroscopic rate of translocation is dependent on both the base moiety and the sugar moiety of the nucleic acid, with approximate macroscopic translocation rates of 3 nt s(-1) (oligo(dT)), 35 nt s(-1) (oligo(dU)), and 42 nt s(-1) (oligo(rU)), respectively. We found a strong correlation between the macroscopic translocation rates and the binding affinity of the translocating NS3h protein for the respective substrates such that weaker affinity corresponded to faster translocation. The values of K(0.5) for NS3h translocation at a saturating ATP concentration are as follows: 3.3+/-0.4 microM nucleotide (poly(dT)), 27+/-2 microM nucleotide (poly(dU)), and 36+/-2 microM nucleotide (poly(rU)). Furthermore, results of the isothermal titration of NS3h with these oligonucleotides suggest that differences in TDeltaS(0) are the principal source of differences in the affinity of NS3h binding to these substrates. Interestingly, despite the differences in macroscopic translocation rates and binding affinities, the ATP coupling stoichiometries for NS3h translocation were identical for all three substrates (approximately 0.5 ATP molecule consumed per nucleotide translocated). This similar periodicity of ATP consumption implies a similar mechanism for NS3h translocation along RNA and DNA substrates.

  20. Noncovalent functionalization of graphene attaching [6,6]-phenyl-C61-butyric acid methyl ester (PCBM) and application as electron extraction layer of polymer solar cells.

    PubMed

    Qu, Shuxuan; Li, Minghua; Xie, Lixin; Huang, Xiao; Yang, Jinguo; Wang, Nan; Yang, Shangfeng

    2013-05-28

    A new graphene-fullerene composite (rGO-pyrene-PCBM), in which [6,6]-phenyl-C61-butyric acid methyl ester (PCBM) was attached onto reduced graphene oxide (rGO) via the noncovalent functionalization approach, was reported. The pyrene-PCBM moiety was synthesized via a facile esterification reaction, and pyrene was used as an anchoring bridge to link rGO and PCBM components. FTIR, UV-vis, and XPS spectroscopic characterizations were carried out to confirm the hybrid structure of rGO-pyrene-PCBM, and the composite formation is found to improve greatly the dispersity of rGO in DMF. The geometric configuration of rGO-pyrene-PCBM was studied by Raman, SEM, and AFM analyses, suggesting that the C60 moiety is far from the graphene sheet and is bridged with the graphene sheet via the pyrene anchor. Finally rGO-pyrene-PCBM was successfully applied as electron extraction layer for P3HT:PCBM bulk heterojunction polymer solar cell (BHJ-PSC) devices, affording a PCE of 3.89%, which is enhanced by ca. 15% compared to that of the reference device without electron extraction layer (3.39%). Contrarily, the comparative devices incorporating the rGO or pyrene-PCBM component as electron extraction layer showed dramatically decreased PCE, indicating the importance of composite formation between rGO and pyrene-PCBM components for its electron extraction property.

  1. Synthesis and Characterization of a Heteroleptic Ru(II) Complex of Phenanthroline Containing Oligo-Anthracenyl Carboxylic Acid Moieties

    PubMed Central

    Adeloye, Adewale O.; Ajibade, Peter A.

    2010-01-01

    In an effort to develop new ruthenium(II) complexes, this work describes the design, synthesis and characterization of a ruthenium(II) functionalized phenanthroline complex with extended π-conjugation. The ligand were L1 (4,7-bis(2,3-dimethylacrylic acid)-1,10-phenanthroline), synthesized by a direct aromatic substitution reaction, and L2 (4,7-bis(trianthracenyl-2,3-dimethylacrylic acid)-1,10-phenanthroline), which was synthesized by the dehalogenation of halogenated aromatic compounds using a zero-valent palladium cross-catalyzed reaction in the absence of magnesium-diene complexes and/or cyclooctadienyl nickel (0) catalysts to generate a new carbon-carbon bond (C-C bond) polymerized hydrocarbon units. The ruthenium complex [RuL1L2(NCS)2] showed improved photophysical properties (red-shifted metal-to-ligand charge-transfer transition absorptions and enhanced molar extinction coefficients), luminescence and interesting electrochemical properties. Cyclic and square wave voltammetry revealed five major redox processes. The number of electron(s) transferred by the ruthenium complex was determined by chronocoulometry in each case. The results show that processes I, II and III are multi-electron transfer reactions while processes IV and V involved one-electron transfer reaction. The photophysical property of the complex makes it a promising candidate in the design of chemosensors and photosensitizers, while its redox-active nature makes the complex a potential mediator of electron transfer in photochemical processes. PMID:20957086

  2. Synthesis and carbonic anhydrase inhibitory properties of amino acid - coumarin/quinolinone conjugates incorporating glycine, alanine and phenylalanine moieties.

    PubMed

    Küçükbay, F Zehra; Küçükbay, Hasan; Tanc, Muhammet; Supuran, Claudiu T

    2016-12-01

    N-Protected amino acids (Gly, Ala and Phe) were reacted with amino substituted coumarin and quinolinone derivatives, leading to the corresponding N-protected amino acid-coumarin/quinolinone conjugates. The carbonic anhydrase (CA, EC 4.2.1.1) inhibitory activity of the new compounds was assessed against various human (h) isoforms, such as hCA I, hCA II, hCA IV and hCA XII. The quinolinone conjugates were inactive as enzyme inhibitors, whereas the coumarins were ineffective hCA I/II inhibitors (KIs > 50 μM) but were submicromolar hCA IV and XII inhibitors, with inhibition constants ranging between 92 nM and 1.19 μM for hCA IV, and between 0.11 and 0.79 μM for hCA XII. These coumarin derivatives, as many others reported earlier, thus show an interesting selective inhibitory profile for the membrane-bound over the cytosolic CA isoforms.

  3. Design, synthesis and in vitro evaluation of novel dehydroabietic acid derivatives containing a dipeptide moiety as potential anticancer agents.

    PubMed

    Huang, Xiao-Chao; Jin, Le; Wang, Meng; Liang, Dong; Chen, Zhen-Feng; Zhang, Ye; Pan, Ying-Ming; Wang, Heng-Shan

    2015-01-07

    A series of novel dehydroabietic acid (DHA) chiral dipeptide derivatives were designed and synthesized as potent antitumor agents. The inhibitory activities of these compounds against NCI-H460 (lung), HeLa (epithelial cervical) and MGC-803 (gastric) human cancer cell lines were estimated by MTT assay in vitro. The antitumor activities screening indicated that many compounds showed moderate to high levels of antitumor activities against these three cancer cell lines and most of these compounds displayed more potent inhibitory activities compared with commercial anticancer drug 5-fluorouracil (5-FU). The induction of apoptosis and affects on the cell cycle distribution with compound 8k were investigated by acridine orange/ethidium bromide staining, Hoechst 33258 staining, JC-1 mitochondrial membrane potential staining, TUNEL assay, flow cytometry and the activities of caspase-3 and -9 assay in Hela cells, which exhibited that the compound could induce cell apoptosis in Hela cells. In addition, further investigation showed that apoptosis were associated with loss of mitochondrial membrane potential, enhancement of mitochondrial cytochrome c release and intracellular ROS production, elevation of Bax expression, down-regulation of Bcl-2, and the activation of caspase-9 and -3.

  4. Synthesis and Biological Evaluation of Novel Dehydroabietic Acid Derivatives Conjugated with Acyl-Thiourea Peptide Moiety as Antitumor Agents

    PubMed Central

    Jin, Le; Qu, Hong-En; Huang, Xiao-Chao; Pan, Ying-Ming; Liang, Dong; Chen, Zhen-Feng; Wang, Heng-Shan; Zhang, Ye

    2015-01-01

    A series of dehydroabietic acid (DHAA) acyl-thiourea derivatives were designed and synthesized as potent antitumor agents. The in vitro pharmacological screening results revealed that the target compounds exhibited potent cytotoxicity against HeLa, SK-OV-3 and MGC-803 tumor cell lines, while they showed lower cytotoxicity against HL-7702 normal human river cells. Compound 9n (IC50 = 6.58 ± 1.11 μM) exhibited the best antitumor activity against the HeLa cell line and even displayed more potent inhibitory activity than commercial antitumor drug 5-FU (IC50 = 36.58 ± 1.55 μM). The mechanism of representative compound 9n was then studied by acridine orange/ethidium bromide staining, Hoechst 33,258 staining, JC-1 mitochondrial membrane potential staining, TUNEL assay and flow cytometry, which illustrated that this compound could induce apoptosis in HeLa cells. Cell cycle analysis indicated that compound 9n mainly arrested HeLa cells in the S phase stage. Further investigation demonstrated that compound 9n induced apoptosis of HeLa cells through a mitochondrial pathway. PMID:26132564

  5. Esters of 6-aminohexanoic acid as skin permeation enhancers: The effect of branching in the alkanol moiety.

    PubMed

    Hrabálek, Alexandr; Vávrová, Katerina; Dolezal, Pavel; Machácek, Milos

    2005-07-01

    In order to investigate the effect of branching and cyclization in the hydrophobic part of skin permeation enhancers, 17 novel branched-chain and cyclic 6-aminohexanoic acid esters were prepared. Their permeation enhancing activity was evaluated in vitro using human skin and theophylline as a model drug, and compared to that of the corresponding linear-chain analogues. The results showed that chain branching and cyclization has a negative influence on the enhancing activity of 6-aminohexanoates. For example, the enhancement ratios (ERs) of dodecan-1-yl, dodecan-2-yl, dodecan-4-yl, and cyclododecyl ester were 39.7, 29.3, 3.1, and 2.2, respectively. No significant change in the optimum length of the chain was observed. Dodecan-2-yl 6-aminohexanoate, the most active branched derivative, still maintains a remarkable enhancing activity (ER 29.3). Presumably, the relatively small degree of branching of these molecules does not prevent them from interacting with the lipid components of the stratum corneum. However, a higher degree of branching, cyclization of the chain, and presence of an aromatic ring resulted in a loss of activity.

  6. Toxicity of synthetic herbicides containing 2,4-D and MCPA moieties towards Pseudomonas putida mt-2 and its response at the level of membrane fatty acid composition.

    PubMed

    Piotrowska, Aleksandra; Syguda, Anna; Chrzanowski, Łukasz; Heipieper, Hermann J

    2016-02-01

    One of the attempts to create more effective herbicidal compounds includes the use of ionic liquids. Herbicidal ionic liquids have more effective biological activity, they are less volatile, more thermally stable, and exhibit superior efficiency in comparison to typically employed herbicides, allowing the reduction of the herbicide dose applied per hectare. However, studies on the environmental toxicity of this group of compounds are very rarely available. Environmental toxicity is an important factor, showing the concentration of compounds that has negative effects on soil bacteria including those responsible for biodegradation processes. Therefore, potential toxicity of four herbicidal ionic liquids (HILs) precursors containing 2,4-D and MCPA moieties was tested with the well investigated model organism for toxicity and adaptation, Pseudomonas putida mt-2. Results were compared to those obtained for commercial 2,4-D and MCPA herbicides. Next to growth inhibition, given as EC50, changes in the isomerisation of cis to trans unsaturated fatty acids were applied as proxy for cellular stress adaptation to toxic substances. The results revealed that all investigated precursors of HILs showed lower toxicity compared to commercialized synthetic herbicides 2,4-D and MCPA. The collected data on toxicity of HILs together with their physico-chemical properties might be useful for assessing the potential risk of the environmental pollution as well as guidelines for setting the legislation for their future use.

  7. Protein Synthesis and Deoxyribonucleic Acid-Membrane Attachment During Thymineless Death in Escherichia coli

    PubMed Central

    Dankberg, Frances; Cummings, Donald J.

    1973-01-01

    The proteins synthesized during thymineless death in Escherichia coli B and B/r were analyzed by polyacrylamide gel elctrophoresis. It was found that the amount of a protein of molecular weight 80,000 to 88,000 is greatly increased during thymineless death compared to the amounts of other cell proteins. A technique for the isolation of cell membrane-deoxyribonucleic acid (DNA)-nascent ribonucleic acid (RNA) complex on detergent crystals was used to determine whether DNA might be detached from the cell membrane as a result of thymineless death. It was found that under no conditions of thymineless death or immunity to thymineless death was there any change in the attachment of DNA or pulse-labeled RNA to cell membrane. Images PMID:4570604

  8. Monolaurin and acetic acid inactivation of Listeria monocytogenes attached to stainless steel.

    PubMed

    Oh, D H; Marshall, D L

    1996-03-01

    Individual and combined antimicrobial effects of monolaurin and acetic acid on Listeria monocytogenes planktonic cells or stainless-steel-adherent cells were determined in order to evaluate cell viability during a 25-min exposure period at 25 degrees C. A 10(7)-colony-forming units (CFU)/ml population of planktonic cells was completely inactivated by the synergistic combination of 1% acetic acid with 50 or 100 microg/ml of monolaurin within 25 or 20 min, respectively. Either compound alone caused partial but incomplete inactivation within the same time periods. A population of 10(5) CFU/cm2 of 1-day adherent cells on stainless steel was completely inactivated within 25 min, but with the highest concentrations of the combined chemicals, i.e., 1% acetic acid and 100 microg/ml of monolaurin. The combined chemical treatment again synergistically produced greater inhibition. A 10(6)-CFU/cm2 population of 7-day adherent cells was not completely inactivated within 25 min of exposure, although counts did decline. The results demonstrate increased resistance of attached L. monocytogenes to acetic acid and monolaurin and show that resistance increased with culture age. Combinations of organic acids and monolaurin might be considered as sanitizers of food contact surfaces, but activities of such combinations are likely to be less than other commonly used sanitizers.

  9. Investigating the chemical changes of chlorogenic acids during coffee brewing: conjugate addition of water to the olefinic moiety of chlorogenic acids and their quinides.

    PubMed

    Matei, Marius Febi; Jaiswal, Rakesh; Kuhnert, Nikolai

    2012-12-12

    Coffee is one of the most popular and consumed beverages in the world and is associated with a series of benefits for human health. In this study we focus on the reactivity of chlorogenic acids, the most abundant secondary metabolites in coffee, during the coffee brewing process. We report on the hydroxylation of the chlorogenic acid cinnamoyl substituent by conjugate addition of water to form 3-hydroxydihydrocaffeic acid derivatives using a series of model compounds including monocaffeoyl and dicaffeoylquinic acids and quinic acid lactones. The regiochemistry of conjugate addition was established based on targeted tandem MS experiments. Following conjugate addition of water a reversible water elimination yielding cis-cinnamoyl derivatives accompanied by acyl migration products was observed in model systems. We also report the formation of all of these derivatives during the coffee brewing process.

  10. A single site in human β-hexosaminidase A binds both 6-sulfate-groups on hexosamines and the sialic acid moiety of GM2 ganglioside

    PubMed Central

    Sharma, Rohita; Bukovac, Scott; Callahan, John; Mahuran, Don

    2010-01-01

    Human β-hexosaminidase A (Hex A) (αβ) is composed of two subunits whose primary structures are ~60% identical. Deficiency of either subunit results in severe neurological disease due to the storage of GM2 ganglioside; Tay–Sachs disease, α deficiency, and Sandhoff disease, β deficiency. Whereas both subunits contain active sites only the α-site can efficiently bind negatively charged 6-sulfated hexosamine substrates and GM2 ganglioside. We have recently identified the αArg424 as playing a critical role in the binding of 6-sulfate-containing substrates, and βAsp452 as actively inhibiting their binding. To determine if these same residues affect the binding of the sialic acid moiety of GM2 ganglioside, an αArg424Gln form of Hex A was expressed and its kinetics analyzed using the GM2 activator protein:[3H]-GM2 ganglioside complex as a substrate. The mutant showed a ~3-fold increase in its Km for the complex. Next a form of Hex B (ββ) containing a double mutation, βAspLeu453 AsnArg (duplicating the α-aligning sequences), was expressed. As compared to the wild type (WT), the mutant exhibited a >30-fold increase in its ability to hydrolyze a 6-sulfated substrate and was now able to hydrolyze GM2 ganglioside when the GM2 activator protein was replaced by sodium taurocholate. Thus, this α-site is critical for binding both types of negatively charge substrates. PMID:12527415

  11. Surface tailoring of poly(DL-lactic acid) by ligand-tethered amphiphilic polymer for promoting chondrocyte attachment and growth.

    PubMed

    Ji, Jian; Zhu, Huiguang; Shen, Jiacong

    2004-05-01

    The ligand-tethered poly(ethylene oxide-propylene oxide-ethylene oxide) (PEO-PPO-PEO) triblock copolymer was explored to engineer poly(DL-lactic acid) (PDL-LA) material to promote cell attachment and growth. The PEO-PPO-PEO was activated by methyl sulfonyl chloride and the amino acid, and peptide were attached. By blending the PDL-LA with the ligand-tethered PEO-PPO-PEO derivatives, the surface of modified PDL-LA film was investigated by ATR-FTIR, XPS and contact angle. The chondrocytes test on different PDL-LA films indicated that the PEO-PPO-PEO amino acid and RGD derivatives modified PDL-LA films could promote chondrocyte attachment and growth. This simple surface treatment method may have potentials for tissue engineering and other biomedical applications.

  12. Impact of acid adaptation on attachment of Listeria monocytogenes to stainless steel during long-term incubation under low or moderate temperature conditions and on subsequent recalcitrance of attached cells to lethal acid treatments.

    PubMed

    Giaouris, Efstathios; Chorianopoulos, Nikos; Nychas, George-John

    2014-02-03

    This study aimed to evaluate the possible impact of acid adaptation of Listeria monocytogenes cells on their attachment to stainless steel (SS) during long-term incubation under either low or moderate temperature conditions and on the subsequent recalcitrance of attached cells to lethal acid treatments. Initially, nonadapted or acid-adapted stationary phase L. monocytogenes cells were used to inoculate (ca. 10⁸ CFU/ml) brain-heart infusion (BHI) broth in test tubes containing vertically placed SS coupons. Incubation was carried out at either 5 or 30 °C for up to 15 days, under static conditions. On the 5th, 10th and 15th days of incubation, attached cells were subjected to lethal acid treatments by exposing them, for either 6 or 60 min, to pH 2, adjusted with either hydrochloric or lactic acid. Following the acid treatments, remaining viable cells were detached (through strong vortexing with glass beads) and enumerated by agar plating, and also indirectly quantified by conductance measurements via their metabolic activity. Results obtained from both quantification techniques, employed here in parallel, revealed that although the numbers of attached cells for nonadapted and acid-adapted ones were similar, the latter were found to present significantly (p<0.05) increased recalcitrance to all the acid treatments for both incubation temperatures and all sampling days. In addition and regardless of acid adaptation, when long (60 min) acid treatments were applied, conductance measurements revealed that the weak organic lactic acid exhibited significantly (p<0.05) stronger antilisterial activity compared to the strong inorganic hydrochloric acid (at the same pH value of 2). To conclude, present results show that acid adaptation of L. monocytogenes cells during their planktonic growth is conserved even after 15 days of incubation under both low and moderate temperature conditions, and results in the increased recalcitrance of their sessile population to otherwise lethal

  13. Identification of potential glycan cancer markers with sialic acid attached to sialic acid and up-regulated fucosylated galactose structures in epidermal growth factor receptor secreted from A431 cell line.

    PubMed

    Wu, Shiaw-Lin; Taylor, Allen D; Lu, Qiaozhen; Hanash, Samir M; Im, Hogune; Snyder, Michael; Hancock, William S

    2013-05-01

    We have used powerful HPLC-mass spectrometric approaches to characterize the secreted form of epidermal growth factor receptor (sEGFR). We demonstrated that the amino acid sequence lacked the cytoplasmic domain and was consistent with the primary sequence reported for EGFR purified from a human plasma pool. One of the sEGFR forms, attributed to the alternative RNA splicing, was also confirmed by transcriptional analysis (RNA sequencing). Two unusual types of glycan structures were observed in sEGFR as compared with membrane-bound EGFR from the A431 cell line. The unusual glycan structures were di-sialylated glycans (sialic acid attached to sialic acid) at Asn-151 and N-acetylhexosamine attached to a branched fucosylated galactose with N-acetylglucosamine moieties (HexNAc-(Fuc)Gal-GlcNAc) at Asn-420. These unusual glycans at specific sites were either present at a much lower level or were not observable in membrane-bound EGFR present in the A431 cell lysate. The observation of these di-sialylated glycan structures was consistent with the observed expression of the corresponding α-N-acetylneuraminide α-2,8-sialyltransferase 2 (ST8SiA2) and α-N-acetylneuraminide α-2,8-sialyltransferase 4 (ST8SiA4), by quantitative real time RT-PCR. The connectivity present at the branched fucosylated galactose was also confirmed by methylation of the glycans followed by analysis with sequential fragmentation in mass spectrometry. We hypothesize that the presence of such glycan structures could promote secretion via anionic or steric repulsion mechanisms and thus facilitate the observation of these glycan forms in the secreted fractions. We plan to use this model system to facilitate the search for novel glycan structures present at specific sites in sEGFR as well as other secreted oncoproteins such as Erbb2 as markers of disease progression in blood samples from cancer patients.

  14. Identification of Amino Acid Substitutions with Compensational Effects in the Attachment Protein of Canine Distemper Virus

    PubMed Central

    Sattler, Ursula; Khosravi, Mojtaba; Avila, Mislay; Pilo, Paola; Langedijk, Johannes P.; Ader-Ebert, Nadine; Alves, Lisa A.; Plattet, Philippe

    2014-01-01

    ABSTRACT The hemagglutinin (H) gene of canine distemper virus (CDV) encodes the receptor-binding protein. This protein, together with the fusion (F) protein, is pivotal for infectivity since it contributes to the fusion of the viral envelope with the host cell membrane. Of the two receptors currently known for CDV (nectin-4 and the signaling lymphocyte activation molecule [SLAM]), SLAM is considered the most relevant for host susceptibility. To investigate how evolution might have impacted the host-CDV interaction, we examined the functional properties of a series of missense single nucleotide polymorphisms (SNPs) naturally accumulating within the H-gene sequences during the transition between two distinct but related strains. The two strains, a wild-type strain and a consensus strain, were part of a single continental outbreak in European wildlife and occurred in distinct geographical areas 2 years apart. The deduced amino acid sequence of the two H genes differed at 5 residues. A panel of mutants carrying all the combinations of the SNPs was obtained by site-directed mutagenesis. The selected mutant, wild type, and consensus H proteins were functionally evaluated according to their surface expression, SLAM binding, fusion protein interaction, and cell fusion efficiencies. The results highlight that the most detrimental functional effects are associated with specific sets of SNPs. Strikingly, an efficient compensational system driven by additional SNPs appears to come into play, virtually neutralizing the negative functional effects. This system seems to contribute to the maintenance of the tightly regulated function of the H-gene-encoded attachment protein. IMPORTANCE To investigate how evolution might have impacted the host-canine distemper virus (CDV) interaction, we examined the functional properties of naturally occurring single nucleotide polymorphisms (SNPs) in the hemagglutinin gene of two related but distinct strains of CDV. The hemagglutinin gene encodes

  15. Identification of amino acid substitutions with compensational effects in the attachment protein of canine distemper virus.

    PubMed

    Sattler, Ursula; Khosravi, Mojtaba; Avila, Mislay; Pilo, Paola; Langedijk, Johannes P; Ader-Ebert, Nadine; Alves, Lisa A; Plattet, Philippe; Origgi, Francesco C

    2014-07-01

    The hemagglutinin (H) gene of canine distemper virus (CDV) encodes the receptor-binding protein. This protein, together with the fusion (F) protein, is pivotal for infectivity since it contributes to the fusion of the viral envelope with the host cell membrane. Of the two receptors currently known for CDV (nectin-4 and the signaling lymphocyte activation molecule [SLAM]), SLAM is considered the most relevant for host susceptibility. To investigate how evolution might have impacted the host-CDV interaction, we examined the functional properties of a series of missense single nucleotide polymorphisms (SNPs) naturally accumulating within the H-gene sequences during the transition between two distinct but related strains. The two strains, a wild-type strain and a consensus strain, were part of a single continental outbreak in European wildlife and occurred in distinct geographical areas 2 years apart. The deduced amino acid sequence of the two H genes differed at 5 residues. A panel of mutants carrying all the combinations of the SNPs was obtained by site-directed mutagenesis. The selected mutant, wild type, and consensus H proteins were functionally evaluated according to their surface expression, SLAM binding, fusion protein interaction, and cell fusion efficiencies. The results highlight that the most detrimental functional effects are associated with specific sets of SNPs. Strikingly, an efficient compensational system driven by additional SNPs appears to come into play, virtually neutralizing the negative functional effects. This system seems to contribute to the maintenance of the tightly regulated function of the H-gene-encoded attachment protein. Importance: To investigate how evolution might have impacted the host-canine distemper virus (CDV) interaction, we examined the functional properties of naturally occurring single nucleotide polymorphisms (SNPs) in the hemagglutinin gene of two related but distinct strains of CDV. The hemagglutinin gene encodes the

  16. Optimizing the Electron-Withdrawing Character on Benzenesulfonyl Moiety Attached to a Glyco-Conjugate to Impart Sensitive and Selective Sensing of Cyanide in HEPES Buffer and on Cellulose Paper and Silica Gel Strips.

    PubMed

    Areti, Sivaiah; Bandaru, Sateesh; Yarramala, Deepthi S; Rao, Chebrolu Pulla

    2015-12-15

    Dansyl-derivatized, triazole-linked, glucopyranosyl conjugates, (5F)LOH, (2F)LOH, (1F)LOH, and (0F)LOH were synthesized and characterized. While the (5F)LOH acts as a molecular probe for CN(-), (2F)LOH, (1F)LOH, and (0F)LOH acts as control molecules. The reactivity of CN(-) toward (5F)LOH has been elicited through the changes observed in NMR, ESI MS, emission, and absorption spectroscopy. The conjugate (5F)LOH releases a fluorescent product upon reaction by CN(-) in aqueous acetonitrile medium by exhibiting an ∼125-fold fluorescence enhancement even in the presence of other anions. Fluorescence switch-on behavior has been clearly demonstrated on the basis of the nucleophilic substitution reaction of CN(-) on (5F)LOH. A minimum detection limit of (2.3 ± 0.3) × 10(-7) M (6 ± 1 ppb) was shown by (5F)LOH for CN(-) in solution. All the other anions studied showed no change in the fluorescence emission. The utility of (5F)LOH has been demonstrated by showing its reactivity toward CN(-) on a thin layer of silica gel as well as on Whatman No. 1 cellulose filter paper strips. The role of glucose moiety and the penta-fluorobenzenesulfonyl reactive center present in (5F)LOH in the selectivity of CN(-) over other anions has been demonstrated by fluorescence, absorption and thermodynamics study. Similar studies carried out with the control molecules showed no selectivity for CN(-). The mechanistic aspects of the reactivity of CN(-) toward (5F)LOH were supported by DFT computational study.

  17. Model-Based Phase 3 Dose Selection for HIV-1 Attachment Inhibitor Prodrug BMS-663068 in HIV-1-Infected Patients: Population Pharmacokinetics/Pharmacodynamics of the Active Moiety, BMS-626529

    PubMed Central

    Landry, Ishani; Zhu, Li; Abu Tarif, Malaz; Hruska, Matthew; Sadler, Brian M.; Pitsiu, Maria; Joshi, Samit; Hanna, George J.; Lataillade, Max; Boulton, David W.

    2016-01-01

    BMS-663068 is an oral prodrug of the HIV-1 attachment inhibitor BMS-626529, which prevents viral attachment to host CD4+ T cells by binding to HIV-1 gp120. To guide dose selection for the phase 3 program, pharmacokinetic/pharmacodynamic modeling was performed using data from two phase 2 studies with HIV-1-infected subjects (n = 244). BMS-626529 population pharmacokinetics were described by a two-compartment model with first-order elimination from the central compartment, zero-order release of prodrug from the extended-release formulation into a hypothetical absorption compartment, and first-order absorption into the central compartment. The covariates of BMS-663068 formulation type, lean body mass, baseline CD8+ T-cell percentage, and ritonavir coadministration were found to be significant contributors to intersubject variability. Exposure-response analyses showed a relationship between the loge-transformed concentration at the end of a dosing interval (Ctau) normalized for the protein binding-adjusted BMS-626529 half-maximal (50%) inhibitory concentration (PBAIC50) and the change in the HIV-1 RNA level from the baseline level after 7 days of BMS-663068 monotherapy. The probability of achieving a decline in HIV-1 RNA level of >0.5 or >1.0 log10 copies/ml as a function of the loge-transformed PBAIC50-adjusted Ctau after 7 days of monotherapy was 99 to 100% and 57 to 73%, respectively, for proposed BMS-663068 doses of 400 mg twice daily (BID), 600 mg BID (not studied in the phase 2b study), 800 mg BID, 600 mg once daily (QD), and 1,200 mg QD. On the basis of a slight advantage in efficacy of BID dosing over QD dosing, similar responses for the 600- and 800-mg BID doses, and prior clinical observations, BMS-663068 at 600 mg BID was predicted to have the optimal benefit-risk profile and selected for further clinical investigation. (The phase 2a proof-of-concept study AI438006 and the phase 2b study AI438011 are registered at ClinicalTrials.gov under numbers NCT01009814

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

    PubMed

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

    2017-03-13

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

  19. Plane wave density functional theory studies of the structural and the electronic properties of amino acids attached to graphene oxide via peptide bonding

    NASA Astrophysics Data System (ADS)

    Min, Byeong June; Jeong, Hae Kyung; Lee, ChangWoo

    2015-08-01

    We studied via plane wave pseudopotential total-energy calculations within the local spin density approximation (LSDA) the electronic and the structural properties of amino acids (alanine, glycine, and histidine) attached to graphene oxide (GO) by peptide bonding. The HOMO-LUMO gap, the Hirshfeld charges, and the equilibrium geometrical structures exhibit distinctive variations that depend on the species of the attached amino acid. The GO-amino acid system appears to be a good candidate for a biosensor.

  20. Voltammetric Detection of Oxalic Acid by Using Glassy Carbon Electrodes with Covalently Attached Nitrogen-containing Functional Groups.

    PubMed

    Matsuura, Hiroaki; Akabe, Syuhei; Kitamura, Tsubasa; Takahashi, Takuto; Uchiyama, Shunichi

    2015-01-01

    We report on a novel voltammetric detection of oxalic acid by using glassy carbon electrodes with covalently attached nitrogen-containing functional groups prepared by stepwise electrolysis. A glassy carbon electrode electrooxidized in an ammonium carbamate solution was electroreduced at -1.0 V (vs. Ag/AgCl) in 1.0 M sulfuric acid for a long time. We found that the electrocatalytic oxidation wave of oxalic acid obtained by this modified glassy carbon electrode was moved to a more negative potential region than that obtained by a platinum electrode in an acidic medium. A good linearity for the peak current signals was observed in the concentration range from 0.1 to 50 mM.

  1. Change in attachment of Salmonella Typhimurium, Yersinia enterocolitica, and Listeria monocytogenes to pork skin and muscle after hot water and lactic acid decontamination.

    PubMed

    Morild, Rikke K; Olsen, John E; Aabo, Søren

    2011-01-31

    The attachment of Salmonella enterica subsp. enterica serovar Typhimurium, Yersinia enterocolitica, and Listeria monocytogenes to pig skin and muscle tissue decontaminated with 80 °C water or 55 °C, 1% lactic acid for 5 and 15s was investigated. Attachment properties differed between skin and muscle surfaces. A significantly higher number of firmly attached bacteria was found on the decontaminated skin surface compared to the non-treated skin surface, both on hot water (P<0.0001) and on lactic acid treated skin (P<0.001). At the muscle surfaces, no such difference in attachment were shown between hot water treated surfaces and non-treated surfaces. In contrast, for lactic acid decontamination, significantly fewer bacteria attached to the treated muscle surfaces (P<0.0001). The study did not show significant differences in surface attachment, between Salmonella, Yersinia and Listeria, which indicate that surface and environmental factors may influence attachment more than bacterial properties. A more profound location of attached bacteria at muscle compared to skin was indicated. Confocal laser scanning microscopy studies showed that bacteria located in deep tissue structures of non-decontaminated and decontaminated skin and muscle surfaces. In the latter, bacteria tended to "hide" between the muscle fibres and may be entrapped at those sites. The finding of changed attachment properties at skin after decontamination may play a role in cross- and recontamination, during subsequent meat processing.

  2. Effect of acid tolerance response (ATR) on attachment of Listeria monocytogenes Scott A to stainless steel under extended exposure to acid or/and salt stress and resistance of sessile cells to subsequent strong acid challenge.

    PubMed

    Chorianopoulos, Nikos; Giaouris, Efstathios; Grigoraki, Ioanna; Skandamis, Panagiotis; Nychas, George-John

    2011-02-28

    The aim of this study was to investigate the potential effect of adaptive stationary phase acid tolerance response (ATR) of Listeria monocytogenes Scott A cells on their attachment to stainless steel (SS) under low pH or/and high salt conditions and on the subsequent resistance of sessile cells to strong acid challenge. Nonadapted or acid-adapted stationary-phase L. monocytogenes cells were used to inoculate (ca. 10⁸ CFU/ml) Brain Heart (BH) broth (pH 7.4, 0.5% w/v NaCl) in test tubes containing vertically placed SS coupons (used as abiotic substrates for bacterial attachment). Incubation was carried out at 16 °C for up to 15 days, without any nutrient refreshment. L. monocytogenes cells, prepared as described above, were also exposed to low pH (4.5; adjusted with HCl) or/and high salt (5.5% w/v NaCl) stresses, during attachment. On the 5th, 10th and 15th day of incubation, cells attached to SS coupons were detached (through bead vortexing) and enumerated (by agar plating). Results revealed that ATR significantly (p<0.05) affected bacterial attachment, when the latter took place under moderate acidic conditions (pH 4.5, 0.5 or 5.5% w/v NaCl), with the acid-adapted cells adhering slightly more than the nonadapted ones. Regardless of acidity/salinity conditions during attachment, ATR also enhanced the resistance of sessile cells to subsequent lethal acid challenge (exposure to pH 2 for 6 min; pH adjusted with either hydrochloric or lactic acid). The trend observed with viable count data agreed well with conductance measurements, used to indirectly quantify remaining attached bacteria (following the strong acid challenge) via their metabolic activity. To sum, this study demonstrates that acid adaptation of L. monocytogenes cells during their planktonic growth enhances their subsequent attachment to SS under extended exposure (at 16 °C for up to 15 days) to mild acidic conditions (pH 4.5), while it also improves the resistance of sessile cells to extreme acid

  3. Influence of different amino substituents in position 1 and 4 on spectroscopic and acid base properties of 9,10-anthraquinone moiety.

    PubMed

    Wcisło, Anna; Niedziałkowski, Paweł; Wnuk, Elżbieta; Zarzeczańska, Dorota; Ossowski, Tadeusz

    2013-05-01

    A series of novel 1-amino and 1,4-diamino-9,10-anthraquinones, substituted with different alkyl groups, were synthesized as the result of alkylation with amino substituents. All the obtained aminoanthraquinone derivatives were characterized by NMR, IR spectroscopy and mass spectrometry. The spectroscopic properties of these compounds were determined by using UV-Vis spectroscopy in acetonitrile, and in the mixture of acetonitrile and methanol at different pH ranges. The effects of various substituents present in the newly developed anthraquinone derivatives and their ability to form hydrogen bonds between the carbonyl oxygen atom of anthraquinone moiety and nitrogen atom of N-H group in 1-aminoanthraquinone (1-AAQ) and 1,4-diaminoanthraquinone (1,4-DAAQ) were studied. Additionally, the effects of hydrogen bond formation between O-H group in hydroxyethylamino substituent and the carbonyl oxygen atom of anthraquinone were investigated. The spectroscopic behavior of the studied derivatives strongly depended on the solvent-solute interactions and the nature of solvent. The values of pKa for the new anthraquinones were determined by the combined potentiometric and spectrophotometric titration methods.

  4. Influence of different amino substituents in position 1 and 4 on spectroscopic and acid base properties of 9,10-anthraquinone moiety

    NASA Astrophysics Data System (ADS)

    Wcisło, Anna; Niedziałkowski, Paweł; Wnuk, Elżbieta; Zarzeczańska, Dorota; Ossowski, Tadeusz

    2013-05-01

    A series of novel 1-amino and 1,4-diamino-9,10-anthraquinones, substituted with different alkyl groups, were synthesized as the result of alkylation with amino substituents. All the obtained aminoanthraquinone derivatives were characterized by NMR, IR spectroscopy and mass spectrometry. The spectroscopic properties of these compounds were determined by using UV-Vis spectroscopy in acetonitrile, and in the mixture of acetonitrile and methanol at different pH ranges. The effects of various substituents present in the newly developed anthraquinone derivatives and their ability to form hydrogen bonds between the carbonyl oxygen atom of anthraquinone moiety and nitrogen atom of N-H group in 1-aminoanthraquinone (1-AAQ) and 1,4-diaminoanthraquinone (1,4-DAAQ) were studied. Additionally, the effects of hydrogen bond formation between O-H group in hydroxyethylamino substituent and the carbonyl oxygen atom of anthraquinone were investigated. The spectroscopic behavior of the studied derivatives strongly depended on the solvent-solute interactions and the nature of solvent. The values of pKa for the new anthraquinones were determined by the combined potentiometric and spectrophotometric titration methods.

  5. Ketopremithramycins and ketomithramycins, four new aureolic acid-type compounds obtained upon inactivation of two genes involved in the biosynthesis of the deoxysugar moieties of the antitumor drug mithramycin by Streptomyces argillaceus, reveal novel insights into post-PKS tailoring steps of the mithramycin biosynthetic pathway.

    PubMed

    Remsing, Lily L; Garcia-Bernardo, Jose; Gonzalez, Ana; Künzel, Eva; Rix, Uwe; Braña, Alfredo F; Bearden, Daniel W; Méndez, Carmen; Salas, Jose A; Rohr, Jürgen

    2002-02-27

    Mithramycin is an aureolic acid-type antimicrobial and antitumor agent produced by Streptomyces argillaceus. Modifying post-polyketide synthase (PKS) tailoring enzymes involved in the production of mithramycin is an effective way of gaining further information regarding the late steps of its biosynthetic pathway. In addition, new "unnatural" natural products of the aureolic acid-type class are likely to be produced. The role of two such post-PKS tailoring enzymes, encoded by mtmC and mtmTIII, was investigated, and four novel aureolic acid class drugs, two premithramycin-type molecules and two mithramycin derivatives, were isolated from mutant strains constructed by insertional gene inactivation of either of these two genes. From data bank comparisons, the corresponding proteins MtmC and MtmTIII were believed to act as a C-methyltransferase involved in the production of the D-mycarose (sugar E) of mithramycin and as a ketoreductase seemingly involved in the biosynthesis of the mithramycin aglycon, respectively. However, gene inactivation and analysis of the accumulated products revealed that both genes encode enzymes participating in the biosynthesis of the D-mycarose building block. Furthermore, the inactivation of MtmC seems to affect the ketoreductase responsible for 4-ketoreduction of sugar C, a D-olivose. Instead of obtaining premithramycin and mithramycin derivatives with a modified E-sugar upon inactivation of mtmC, compounds were obtained that completely lack the E-sugar moiety and that possess an unexpected 4-ketosugar moiety instead of the D-olivose at the beginning of the lower deoxysaccharide chain. The inactivation of mtmTIII led to the accumulation of 4E-ketomithramycin, showing that this ketoreductase is responsible for the 4-ketoreduction of the D-mycarose moiety. The new compounds of the mutant strains, 4A-ketopremithramycin A2, 4A-keto-9-demethylpremithramycin A2, 4C-keto-demycarosylmithramycin, and 4E-ketomithramycin, indicate surprising substrate

  6. Ketopremithramycins and Ketomithramycins, Four New Aureolic Acid-Type Compounds Obtained upon Inactivation of Two Genes Involved in the Biosynthesis of the Deoxysugar Moieties of the Antitumor Drug Mithramycin by Streptomyces Argillaceus, Reveal Novel Insights into Post-PKS Tailoring Steps of the Mithramycin Biosynthetic Pathway

    PubMed Central

    Remsing, Lily L.; Garcia-Bernardo, Jose; Gonzalez, Ana; Künzel, Eva; Rix, Uwe; Braña, Alfredo F.; Bearden, Daniel W.; Méndez, Carmen; Salas, Jose A.; Rohr, Jürgen

    2015-01-01

    Mithramycin is an aureolic acid-type antimicrobial and antitumor agent produced by Streptomyces argillaceus. Modifying post-polyketide synthase (PKS) tailoring enzymes involved in the production of mithramycin is an effective way of gaining further information regarding the late steps of its biosynthetic pathway. In addition, new “unnatural” natural products of the aureolic acid-type class are likely to be produced. The role of two such post-PKS tailoring enzymes, encoded by mtmC and mtmTIII, was investigated, and four novel aureolic acid class drugs, two premithramycin-type molecules and two mithramycin derivatives, were isolated from mutant strains constructed by insertional gene inactivation of either of these two genes. From data bank comparisons, the corresponding proteins MtmC and MtmTIII were believed to act as a C-methyltransferase involved in the production of the D-mycarose (sugar E) of mithramycin and as a ketoreductase seemingly involved in the biosynthesis of the mithramycin aglycon, respectively. However, gene inactivation and analysis of the accumulated products revealed that both genes encode enzymes participating in the biosynthesis of the D-mycarose building block. Furthermore, the inactivation of MtmC seems to affect the ketoreductase responsible for 4-ketoreduction of sugar C, a D-olivose. Instead of obtaining premithramycin and mithramycin derivatives with a modified E-sugar upon inactivation of mtmC, compounds were obtained that completely lack the E-sugar moiety and that possess an unexpected 4-ketosugar moiety instead of the D-olivose at the beginning of the lower deoxysaccharide chain. The inactivation of mtmTIII led to the accumulation of 4E-ketomithramycin, showing that this ketoreductase is responsible for the 4-ketoreduction of the D-mycarose moiety. The new compounds of the mutant strains, 4A-ketopremithramycin A2, 4A-keto-9-demethylpremithramycin A2, 4C-keto-demycarosylmithramycin, and 4E-ketomithramycin, indicate surprising

  7. Retinoic acid conjugates as potential antitumor agents: synthesis and biological activity of conjugates with Ara-A, Ara-C, 3(2H)-furanone, and aniline mustard moieties.

    PubMed

    Manfredini, S; Simoni, D; Ferroni, R; Bazzanini, R; Vertuani, S; Hatse, S; Balzarini, J; De Clercq, E

    1997-11-07

    In a dual targeting approach, to explore the ability of tretinoin (all-trans-retinoic acid) to behave as a covalent carrier for cytotoxic entities, conjugates of retinoic acid with a few representative molecules, being important examples of antitumor pharmacophores (i.e., nucleoside analogues and alkylating agents), have been synthesized and tested for their cytostatic and differentiating activity. All compounds were stable to in vitro hydrolysis in human plasma and more lipophilic than the parent compounds, thus consenting enhanced uptake into the cells. Among the nucleoside analogues the Ara-C derivatives 3 and 6 and the Ara-A derivative 7 proved the most cytostatic (IC50 < 0.32 microgram/mL) resulting from 25- to > 144-fold more active (Ara-A derivatives) or at least as equally active (Ara-C derivatives) as compared to the parent nucleosides. Compound 3, endowed with a highly lipophilic silyl moiety at the 3' and 5' positions, showed the highest differentiating activity (54% and 44% differentiated HL-60 cells at 0.2 and 0.05 microgram/mL respectively). With regard to the retinoic acid conjugates of alkylating agents, compound 10 was the most cytostatic agent (IC50 < 0.32 microgram/mL) and the most potent differentiating agent (33-34% at 0.32 and 0.08 microgram/mL). These structures may also be regarded as analogs of either retinoic acid or the cytotoxic compound.

  8. Dissociative Electron Attachment to Phosphoric Acid Esters: The Direct Mechanism for Single Strand Breaks in DNA

    SciTech Connect

    Koenig, Constanze; Kopyra, Janina; Bald, Ilko; Illenberger, Eugen

    2006-07-07

    We use dibutyl phosphate to simulate the behavior of the phosphate group in DNA towards the attack of low energy electrons. We find that the compound undergoes effective dissociative electron attachment within a low energy resonant feature at 1 eV and a further resonance peaking at 8 eV. The dissociative electron attachment (DEA) reactions are associated with the direct cleavage of the C-O and the P-O bond but also the excision of the PO{sup -}, PO{sub 3}{sup -}, H{sub 2}PO{sub 3}{sup -} units. For the phosphate group coupled in the DNA network these reactions represent single strand breaks. We hence propose that the most direct mechanism of single strand breaks occurring in DNA at subexcitation energies (<4 eV) is due to DEA directly to the phosphate group.

  9. Photophysics and photochemistry of the UV filter kynurenine covalently attached to amino acids and to a model protein.

    PubMed

    Sherin, Peter S; Grilj, Jakob; Kopylova, Lyudmila V; Yanshole, Vadim V; Tsentalovich, Yuri P; Vauthey, Eric

    2010-09-16

    The photophysics and photochemistry of kynurenine (KN) covalently bound to the amino acids lysine, cysteine, and histidine, the antioxidant glutathione, and the protein lysozyme have been studied by optical spectroscopy with femto- and nanosecond time resolution. The fluorescence quantum yield of the adducts of KN to amino acids is approximately 2 times higher than that of the free KN in solution; KN attached to protein exhibits a 7-fold increase in the fluorescence quantum yield. The S(1) state dynamics of KN-modified lysozyme reveals a multiphasic decay with a broad dispersion of time constants from 1 ps to 2 ns. An increase of the triplet yield of KN bound to lysozyme is also observed; the triplet state undergoes fast intramolecular decay. The obtained results reveal an increase of the photochemical activity of KN after its covalent attachment to amino acids and proteins, which may contribute to the development of oxidative stress in the human lenses-the main causative factor for the cataract onset.

  10. Intraperiplasmic growth of Bdellovibrio bacteriovorus 109J: attachment of long-chain fatty acids to escherichia coli peptidoglycan.

    PubMed Central

    Thomashow, M F; Rittenberg, S C

    1978-01-01

    During the initial stages of intraperiplasmic growth of Bdellovibrio bacteriovorus on Escherichia coli, the peptidoglycan of the E. coli becomes acylated with long-chain fatty acids, primarily palmitic acid (60%) and oleic acid (20%). The attachment of the fatty acids to the peptidoglycan involves a carboxylic-ester bond, i.e., they were removed by treatment with alkaline hydroxylamine. Their linkage to the peptidoglycan does not involve a protein molecule. When the bdelloplast peptidoglycan was digested with lysozyme, the fatty acid-containing split products behaved as lipopeptidoglycan, i.e., they were extracted into the organic phase of 1-butanol:acetic acid:water (4:15) two-phase system; all of the lysozyme split products generated from normal E. coli peptidoglycan were extracted into the water phase. It is suggested that the function of the acylation reaction is to help stabilize the bdelloplast outer membrane against osmotic forces. In addition, a model is presented to explain how a bdellovibrio penetrates, stabilizes, and lyses a substrate cell. PMID:357411

  11. Comparison of silatrane, phosphonic acid, and carboxylic acid functional groups for attachment of porphyrin sensitizers to TiO2 in photoelectrochemical cells.

    PubMed

    Brennan, Bradley J; Llansola Portolés, Manuel J; Liddell, Paul A; Moore, Thomas A; Moore, Ana L; Gust, Devens

    2013-10-21

    A tetra-arylporphyrin dye was functionalized with three different anchoring groups used to attach molecules to metal oxide surfaces. The physical, photophysical and electrochemical properties of the derivatized porphyrins were studied, and the dyes were then linked to mesoporous TiO2. The anchoring groups were β-vinyl groups bearing either a carboxylate, a phosphonate or a siloxy moiety. The siloxy linkages were made by treatment of the metal oxide with a silatrane derivative of the porphyrin. The surface binding and lability of the anchored molecules were studied, and dye performance was compared in a dye-sensitized solar cell (DSSC). Transient absorption spectroscopy was used to study charge recombination processes. At comparable surface concentration, the porphyrin showed comparable performance in the DSSC, regardless of the linker. However, the total surface coverage achievable with the carboxylate was about twice that obtainable with the other two linkers, and this led to higher current densities for the carboxylate DSSC. On the other hand, the carboxylate-linked dyes were readily leached from the metal oxide surface under alkaline conditions. The phosphonates were considerably less labile, and the siloxy-linked porphyrins were most resistant to leaching from the surface. The use of silatrane proved to be a practical and convenient way to introduce the siloxy linkages, which can confer greatly increased stability on dye-sensitized electrodes with photoelectrochemical performance comparable to that of the other linkers.

  12. Effect of binding of Calcofluor White on the carbohydrate residues of alpha1-acid glycoprotein (orosomucoid) on the structure and dynamics of the protein moiety. A fluorescence study.

    PubMed

    Albani, J R

    2001-08-23

    Calcofluor White is a fluorescent probe that interacts with polysaccharides and is commonly used in clinical studies. Interaction between Calcofluor White and carbohydrate residues of alpha1-acid glycoprotein (orosomucoid) was previously studied at low and high concentrations of Calcofluor compared to that of the protein. alpha1-Acid glycoprotein contains 40% carbohydrate by weight and has up to 16 sialic acid residues. At equimolar concentrations of Calcofluor and alpha1-acid glycoprotein, the fluorophore displays free motions [Albani, J. R.; Sillen, A.; Coddeville, B.; Plancke, Y. D.; Engelborghs, Y. Carbohydr. Res. 1999, 322, 87-94], while at high concentration of Calcofluor, its surrounding microenvironment is rigid, inducing the rigidity of the fluorophore itself [Albani, J. R.; Sillen, A.; Plancke, Y. D.; Coddeville, B.; Engelborghs, Y. Carbohydr. Res. 2000, 327, 333-340]. In the present work, red-edge excitation spectra and steady-state anisotropy studies performed on Trp residues in the presence of Calcofluor, showed that the apparent dynamics of Trp residues are not modified. However, deconvoluting the emission spectra with two different methods into different components, reveals that the structure of the protein matrix has been disrupted in the presence of high Calcofluor concentrations.

  13. 9-fluorenylmethyl chloroformate as a fluorescence-labeling reagent for derivatization of carboxylic acid moiety of sodium valproate using liquid chromatography/tandem mass spectrometry for binding characterization: a human pharmacokinetic study.

    PubMed

    Mohammadi, Bahareh; Majnooni, Mohammad Bagher; Khatabi, Pyman Malek; Jalili, Ronak; Bahrami, Gholamreza

    2012-01-01

    In High Performance Liquid Chromatographic (HPLC) determination of chemicals with acidic functions, different labeling agents are used to improve sensitivity of the assay. 9-Fluorenylmethyl chloroformate (FMOC-Cl), on the other hand, is a suitable labeling agent, which reacts with both primary and secondary amines and less readily with hydroxyl groups in alkaline conditions. However, the reagent has not been applied in labeling of chemicals with acidic function yet. In this study which is the first report on application of FMOC-Cl in derivatization and analysis of a drug with acidic function, valproic acid (VPA), one of a series of fatty carboxylic acids with anticonvulsant activity, was derivatized using the reagent and quantified in serum samples by HPLC with fluorescence detection. In addition, to document the reaction between the labeling agent and carboxylic acid moiety of the drug, we developed a liquid chromatography-tandem MS/MS (LC-MS/MS) method. Following liquid-liquid extraction, derivatization of the drug and an internal standard was achieved in alkaline medium. The elute was monitored by a fluorescence detector with respective excitation and emission wavelengths of 265 and 315 nm. The present method is more sensitive comparing with other published HPLC procedures for analysis of VPA. The assay is sensitive enough to measure drug levels obtained in human single dose studies with a limit of quantification of 0.01 μg/mL. Also the method is linear over the concentrations range of 0.01-32 μg/mL of VPA in human serum using 100 μL serum sample and 5 μL injection. The coefficient variation values of both inter and intra day analysis were less than 12% and the percentage error was less than 4%. The method performance was studied and the validated procedure applied in a randomized cross-over bioequivalence study of two different VPA preparations in 24 healthy volunteers.

  14. Novel proton exchange membranes based on cardo poly(arylene ether sulfone/nitrile)s with perfluoroalkyl sulfonic acid moieties for passive direct methanol fuel cells

    NASA Astrophysics Data System (ADS)

    Zheng, Jifu; He, Qingyi; Gao, Nian; Yuan, Ting; Zhang, Suobo; Yang, Hui

    2014-09-01

    A new series of cardo poly(arylene ether sulfone/nitrile)s FSPES-x with perfluoroalkyl sulfonic acid groups have been successfully prepared by the perfluorosulfonic acid lactone ring-opening reaction without using any metal or base catalysts. These materials have been characterized by IR, NMR and TGA. The results indicate that this simple and metal-free method of preparation is highly efficient for controlling both the degree of perfluorosulfonation and the position of the sulfonate group and no side reactions such as crosslinking is observed. The FSPES-x membranes (IEC = 1.17-1.64 m equiv g-1) show the desired characteristics such as good film-forming ability, excellent thermal and mechanical properties, low methanol permeability, high conductivity (up to 0.083 S cm-1 at room temperature), as well as appropriate cell performance compared to Nafion®117. With these properties, such fluorinated sulfonic acid side-chain-type polymers are promising PEM materials for application in fuel cells.

  15. Covalent attachment of diamondoid phosphonic acid dichlorides to tungsten oxide surfaces.

    PubMed

    Li, Fei Hua; Fabbri, Jason D; Yurchenko, Raisa I; Mileshkin, Alexander N; Hohman, J Nathan; Yan, Hao; Yuan, Hongyuan; Tran, Ich C; Willey, Trevor M; Bagge-Hansen, Michael; Dahl, Jeremy E P; Carlson, Robert M K; Fokin, Andrey A; Schreiner, Peter R; Shen, Zhi-Xun; Melosh, Nicolas A

    2013-08-06

    Diamondoids (nanometer-sized diamond-like hydrocarbons) are a novel class of carbon nanomaterials that exhibit negative electron affinity (NEA) and strong electron-phonon scattering. Surface-bound diamondoid monolayers exhibit monochromatic photoemission, a unique property that makes them ideal electron sources for electron-beam lithography and high-resolution electron microscopy. However, these applications are limited by the stability of the chemical bonding of diamondoids on surfaces. Here we demonstrate the stable covalent attachment of diamantane phosphonic dichloride on tungsten/tungsten oxide surfaces. X-ray photoelectron spectroscopy (XPS) and Fourier-transform infrared (FTIR) spectroscopy revealed that diamondoid-functionalized tungsten oxide films were stable up to 300-350 °C, a substantial improvement over conventional diamondoid thiolate monolayers on gold, which dissociate at 100-200 °C. Extreme ultraviolet (EUV) light stimulated photoemission from these diamondoid phosphonate monolayers exhibited a characteristic monochromatic NEA peak with 0.2 eV full width at half-maximum (fwhm) at room temperature, showing that the unique monochromatization property of diamondoids remained intact after attachment. Our results demonstrate that phosphonic dichloride functionality is a promising approach for forming stable diamondoid monolayers for elevated temperature and high-current applications such as electron emission and coatings in micro/nano electromechanical systems (MEMS/NEMS).

  16. Efficacy of Acetic Acid against Listeria monocytogenes Attached to Poultry Skin during Refrigerated Storage.

    PubMed

    Gonzalez-Fandos, Elena; Herrera, Barbara

    2014-09-11

    This work evaluates the effect of acetic acid dipping on the growth of L. monocytogenes on poultry legs stored at 4 °C for eight days. Fresh inoculated chicken legs were dipped into either a 1% or 2% acetic acid solution (v/v) or distilled water (control). Changes in mesophiles, psychrotrophs, Enterobacteriaceae counts and sensorial characteristics (odor, color, texture and overall appearance) were also evaluated. The shelf life of the samples washed with acetic acid was extended by at least two days over the control samples washed with distilled water. L. monocytogenes counts before decontamination were 5.57 log UFC/g, and after treatment with 2% acetic acid (Day 0), L. monocytogenes counts were 4.47 log UFC/g. Legs washed with 2% acetic acid showed a significant (p < 0.05) inhibitory effect on L. monocytogenes compared to control legs, with a decrease of about 1.31 log units after eight days of storage. Sensory quality was not adversely affected by acetic acid. This study demonstrates that while acetic acid did reduce populations of L. monocytogenes on meat, it did not completely inactivate the pathogen. The application of acetic acid may be used as an additional hurdle contributing to extend the shelf life of raw poultry and reducing populations of L. monocytogenes.

  17. Preparation of Sticky Escherichia coli through Surface Display of an Adhesive Catecholamine Moiety

    PubMed Central

    Park, Joseph P.; Choi, Min-Jung; Kim, Se Hun

    2014-01-01

    Mussels attach to virtually all types of inorganic and organic surfaces in aqueous environments, and catecholamines composed of 3,4-dihydroxy-l-phenylalanine (DOPA), lysine, and histidine in mussel adhesive proteins play a key role in the robust adhesion. DOPA is an unusual catecholic amino acid, and its side chain is called catechol. In this study, we displayed the adhesive moiety of DOPA-histidine on Escherichia coli surfaces using outer membrane protein W as an anchoring motif for the first time. Localization of catecholamines on the cell surface was confirmed by Western blot and immunofluorescence microscopy. Furthermore, cell-to-cell cohesion (i.e., cellular aggregation) induced by the displayed catecholamine and synthesis of gold nanoparticles on the cell surface support functional display of adhesive catecholamines. The engineered E. coli exhibited significant adhesion onto various material surfaces, including silica and glass microparticles, gold, titanium, silicon, poly(ethylene terephthalate), poly(urethane), and poly(dimethylsiloxane). The uniqueness of this approach utilizing the engineered sticky E. coli is that no chemistry for cell attachment are necessary, and the ability of spontaneous E. coli attachment allows one to immobilize the cells on challenging material surfaces such as synthetic polymers. Therefore, we envision that mussel-inspired catecholamine yielded sticky E. coli that can be used as a new type of engineered microbe for various emerging fields, such as whole living cell attachment on versatile material surfaces, cell-to-cell communication systems, and many others. PMID:24123747

  18. [Synthetic transformations of higher terpenoids. XXX. Synthesis and cytotoxic activity of betulonic acid amides with a piperidine or pyrrolidine nitroxide moiety].

    PubMed

    Antimonova, A N; Petrenko, N I; Shults, E E; Polienko, Iu F; Shakirov, M M; Irtegova, I G; Pokrovskiĭ, M A; Sherman, K M; Grigor'ev, I A; Pokrovskiĭ, A G; Tolstikov, G A

    2013-01-01

    The reaction of betulonic acid chloride with 4-amino-2,2,6,6-tetramethylpeperidine-1-oxyl, 3-amino-2,2,5,5-tetramethylpyrrolidine-1-oxyl and 3-aminomethyl-2,2,5,5-tetramethylpyrrolidine-1-oxyl gave corresponding triterpenoid amides. It was found that new derivatives exhibit cytotoxic activity against tumor cells CEM-13, U-937, MT-4. CCID50 value for most activity compound--N-[3-oxolup-20(29)-en-30-yl]-(2,2,6,6-tetramethylpiperidine-4-yl)-1-oxyl--was 5.7-33.1 microM.

  19. Efficacy of malic acid against Listeria monocytogenes attached to poultry skin during refrigerated storage.

    PubMed

    González-Fandos, E; Herrera, B

    2013-07-01

    This work evaluated the effect of malic acid washing on the growth of Listeria monocytogenes on poultry legs stored at 4°C for 8 d. Fresh inoculated chicken legs were dipped into a 1 or 2% malic acid solution (vol/vol) for 5 min or distilled water (control). Surface pH values, sensorial characteristics (odor, color, texture, and overall appearance) and L. monocytogenes, mesophile, psychrotroph, and Enterobacteriaceae counts were evaluated after treatment (d 0) and after 1, 3, 6, and 8 d of storage at 4°C. Legs washed with 2% malic acid showed a significant (P < 0.05) inhibitory effect on L. monocytogenes compared with control legs, with a decrease of about 1.66 log units after treatment. Sensory quality was not adversely affected by malic acid. Treatments with malic acid reduced bacterial growth and preserved reasonable sensorial quality after storage at 4°C for 6 d. This study demonstrates that, although malic acid did reduce populations of L. monocytogenes on poultry, it did not completely inactivate the pathogen. The application of malic acid may be used as an additional hurdle contributing to extend the shelf life of raw poultry.

  20. Effect of propionic acid on Campylobacter jejuni attached to chicken skin during refrigerated storage.

    PubMed

    González-Fandos, Elena; Maya, Naiara; Pérez-Arnedo, Iratxe

    2015-09-01

    The ability of propionic acid to reduce Campylobacter jejuni on chicken legs was evaluated. Chicken legs were inoculated with Campylobacter jejuni. After dipping legs in either water (control), 1% or 2% propionic acid solution (vol/vol), they were stored at 4ºC for 8 days. Changes in C. jejuni, psychrotrophs and Pseudomonas counts were evaluated. Washing in 2% propionic acid significantly reduced C. jejuni counts compared to control legs, with a decrease of about 1.62 log units after treatment. Treatment of chicken legs with 1 or 2% propionic acid significantly reduced numbers of psychrotrophs 1.01 and 1.08 log units and Pseudomonas counts 0.75 and 0.96 log units, respectively, compared to control legs. The reduction in psychrotrophs and Pseudomonas increased throughout storage. The highest reductions obtained for psychrotrophs and Pseudomonas counts in treated legs were reached at the end of storage, day 8, being 3.3 and 2.93 log units, respectively, compared to control legs. Propionic acid treatment was effective in reducing psychrotrophs and Pseudomonas counts on chicken legs throughout storage. It is concluded that propionic acid is effective for reducing C. jejuni populations in chicken.

  1. Role of Cellulose and Colanic Acid in Attachment of Shiga Toxin-Producing Escherichia coli to Lettuce and Spinach in Different Water Hardness Environments.

    PubMed

    Lee, Chi-Ching; Chen, Jinru; Frank, Joseph F

    2015-08-01

    This study investigated the role of extracellular cellulose production by Shiga toxin-producing Escherichia coli (STEC) on attachment to lettuce and spinach in different water hardness environments. Two cellulose-producing wild-type STEC strains, 19 (O5:H-) and 49 (O103:H2), and their cellulose-deficient derivatives were used. Strain 49 also produced colanic acid as a constituent of its extracellular polymeric substances. Attached cells were determined by plate counts on the surface and cut edge of the leaves after an attachment period of 2 h at 4°C. Hydrophobicity and surface charge of the cells were determined. Strain 49 attached at levels 0.3 and 0.6 log greater to the surface and 0.9 and 0.4 log greater to the cut edges of spinach compared to strain 19 for both wild-type and cellulose-deficient cells (P > 0.05). Cellulose-producing cells attached more to the surface of lettuce but not of spinach than did cellulose-deficient cells. However, more cellulose-deficient cells attached (at levels 0.66 and 0.3 log greater) to the cut edge of lettuce (representing damaged tissue) than did cellulose-proficient cells (P > 0.05). Colanic acid production was associated with cell surfaces of low hydrophobicity. There was a decreasing level of attachment for the colanic acid-producing strain when water hardness increased from 200 to 1,000 pm on lettuce and spinach leaf surfaces, but no effects were seen for other cells. This decreased attachment was associated with a more negative surface charge. Cells that produced colanic acid were less hydrophobic and exhibited greater attachment to the surface and cut edge of spinach when compared to cells that did not produce colanic acid. Attachment of colanic acid-producing cells to leafy green surfaces was enhanced in higher water hardness environments. These data indicate that attachment of E. coli O157:H7 to leafy greens involves multiple mechanisms that are influenced by the type of leafy green, damage to the leaf, and the water

  2. Discovery of a novel acyl-CoA: cholesterol acyltransferase inhibitor: the synthesis, biological evaluation, and reduced adrenal toxicity of (4-phenylcoumarin)acetanilide derivatives with a carboxylic acid moiety.

    PubMed

    Ogino, Masaki; Nakada, Yoshihisa; Negoro, Nobuyuki; Itokawa, Shigekazu; Nishimura, Satoshi; Sanada, Tsukasa; Satomi, Tomoko; Kita, Shunbun; Kubo, Kazuki; Marui, Shogo

    2011-01-01

    As a part of our research for novel potent and orally available acyl-CoA: cholesterol acyltransferase (ACAT) inhibitors that can be used as anti-atherosclerotic agents, we recently reported the discovery of the (4-phenylcoumarine)acetanilide derivative 1. However, compound 1 showed adrenal toxicity in animal models. In order to search for safer ACAT inhibitors that do not have adrenal toxicity, we examined the inhibitory activity of ACAT in human macrophage and adrenal cells. The introduction of a carboxylic acid moiety on the pendant phenyl ring and the adjustment of the lipophilicity led to the discovery of (2E)-3-[7-chloro-3-[2-[[4-fluoro-2-(trifluoromethyl)phenyl]amino]-2-oxoethyl]-6-methyl-2-oxo-2H-chromen-4-yl]phenyl]acrylic acid (21e), which showed potent ACAT inhibitory activity in macrophages and a selectivity of around 30-fold over adrenal cells. In addition, compound 21e showed high adrenal safety in guinea pigs.

  3. Structural Studies on Molecular Interactions between Camel Peptidoglycan Recognition Protein, CPGRP-S, and Peptidoglycan Moieties N-Acetylglucosamine and N-Acetylmuramic Acid*

    PubMed Central

    Sharma, Pradeep; Yamini, Shavait; Dube, Divya; Singh, Amar; Sinha, Mau; Dey, Sharmistha; Mitra, Dipendra K.; Kaur, Punit; Sharma, Sujata; Singh, Tej P.

    2012-01-01

    Peptidoglycan (PGN) consists of repeating units of N-acetylglucosamine (GlcNAc) and N-acetylmuramic acid (MurNAc), which are cross-linked by short peptides. It is well known that PGN forms a major cell wall component of bacteria making it an important ligand for the recognition by peptidoglycan recognition proteins (PGRPs) of the host. The binding studies showed that PGN, GlcNAc, and MurNAc bind to camel PGRP-S (CPGRP-S) with affinities corresponding to dissociation constants of 1.3 × 10−9, 2.6 × 10−7, and 1.8 × 10−7 m, respectively. The crystal structure determinations of the complexes of CPGRP-S with GlcNAc and MurNAc showed that the structures consist of four crystallographically independent molecules, A, B, C, and D, in the asymmetric unit that exists as A-B and C-D units of two neighboring linear polymers. The structure determinations showed that compounds GlcNAc and MurNAc bound to CPGRP-S at the same subsite in molecule C. Both GlcNAc and MurNAc form several hydrogen bonds and extensive hydrophobic interactions with protein atoms, indicating the specific nature of their bindings. Flow cytometric studies showed that PGN enhanced the secretions of TNF-α and IL-6 from human peripheral blood mononuclear cells. The introduction of CPGRP-S to the PGN-challenged cultured peripheral blood mononuclear cells reduced the expressions of proinflammatory cytokines, TNF-α and IL-6. This showed that CPGRP-S inhibited PGN-induced production of proinflammatory cytokines and down-regulated macrophage-mediated inflammation, indicating its potential applications as an antibacterial agent. PMID:22573327

  4. The influence of nanotexturing of poly(lactic-co-glycolic acid) films upon human ovarian cancer cell attachment

    NASA Astrophysics Data System (ADS)

    Yaşayan, Gökçen; Xue, Xuan; Collier, Pamela; Clarke, Philip; Alexander, Morgan R.; Marlow, Maria

    2016-06-01

    In this study, we have produced nanotextured poly(lactic-co-glycolic acid) (PLGA) films by using polystyrene (PS) particles as a template to make a polydimethylsiloxane mould against which PLGA is solvent cast. Biocompatible, biodegradable and nanotextured PLGA films were prepared with PS particles of diameter of 57, 99, 210, and 280 nm that produced domes of the same dimension in the PLGA surface. The effect of the particulate monolayer templating method was investigated to enable preparation of the films with uniformly ordered surface nanodomes. Cell attachment of a human ovarian cancer cell line (OVCAR3) alone and co-cultured with mesenchymal stem cells (MSCs) was evaluated on flat and topographically nano-patterned surfaces. Cell numbers were observed to increase on the nanotextured surfaces compared to non-textured surfaces both with OVCAR3 cultures and OVCAR3-MSC co-cultures at 24 and 48 h time points.

  5. Synthesis of the Sugar Moieties

    NASA Astrophysics Data System (ADS)

    Grynkiewicz, Grzegorz; Szeja, Wieslaw

    Biological activity of the anthracycline antibiotics, which have found wide application in clinical oncology, is strongly related to their glycosidic structure. Modification or switch of the saccharide moiety became an important line of new drug discovery and study of their mechanism of action. Natural glycons (sugar moieties) of the anthracycline antibiotics belong to the 2,6-dideoxypyranose family and their principal representative, daunosamine, is 3-amino-2,3,6-trideoxy- l-lyxo-pyranose. Some newer chemical syntheses of this sugar, from a chiral pool as well as from achiral starting materials, are presented and their capability for scale-up and process development are commented upon. Rational sugar structural modifications, which are either useful for synthetic purposes or offer advantages in experimental therapy of cancer, are discussed from the chemical point of view.

  6. Hyaluronic acid capsule modulates M protein-mediated adherence and acts as a ligand for attachment of group A Streptococcus to CD44 on human keratinocytes.

    PubMed Central

    Schrager, H M; Albertí, S; Cywes, C; Dougherty, G J; Wessels, M R

    1998-01-01

    We used wild-type and isogenic mutant strains of group A Streptococcus (GAS) that expressed M protein, capsule, or both to study the function of M protein and the hyaluronic acid capsular polysaccharide in attachment of GAS to human keratinocytes. Types 6 and 24, but not type 18, M protein were found to mediate attachment of GAS to soft palate or skin keratinocytes, but this interaction was prevented by the hyaluronic acid capsule on highly encapsulated, or mucoid, strains. Monoclonal antibody to CD44, the principal hyaluronic acid-binding receptor on keratinocytes, inhibited attachment of both highly encapsulated and poorly encapsulated wild type strains of GAS, but not the attachment of acapsular mutants. Transfection of K562 cells with cDNA encoding human CD44 conferred the capacity to bind each of six wild-type strains of GAS, but not to bind acapsular mutants. Because, in contrast to other potential adhesins, the group A streptococcal capsule is both highly conserved and surface-exposed, it may serve as a universal adhesin for attachment of diverse strains of GAS to keratinocytes of the pharyngeal mucosa and the skin. PMID:9541502

  7. 1-Heteroaryl-3-phenoxypropan-2-ones as inhibitors of cytosolic phospholipase A₂α and fatty acid amide hydrolase: Effect of the replacement of the ether oxygen with sulfur and nitrogen moieties on enzyme inhibition and metabolic stability.

    PubMed

    Sundermann, Tom; Fabian, Jörg; Hanekamp, Walburga; Lehr, Matthias

    2015-05-15

    Cytosolic phospholipase A2α (cPLA2α) and fatty acid amide hydrolase (FAAH) are enzymes, which have emerged as attractive targets for the development of analgesic and anti-inflammatory drugs. We recently reported that certain 3-phenoxy-substituted 1-heteroarylpropan-2-ones are inhibitors of cPLA2α and/or FAAH. Starting from 1-[2-oxo-3-(4-phenoxyphenoxy)propyl]indole-5-carboxylic acid (3) and 1-(1H-benzotriazol-1-yl)-3-(4-phenoxyphenoxy)propan-2-one (4), the effect of the replacement of the oxygen in position 3 of the propan-2-one scaffold by sulfur and nitrogen containing moieties on inhibition of cPLA2α and fatty acid amide hydrolase as well as on metabolic stability in rat liver S9 fractions was investigated. As a result of these structure-activity relationship studies it was found that the ether oxygen is of great importance for enzyme inhibitory potency. Replacement by sulfur led to an about 100-fold decrease of enzyme inhibition, nitrogen and substituted nitrogen atoms at this position even resulted in inactivity of the compounds. The effect of the structural variations performed on metabolic stability of the important ketone pharmacophore was partly different in the two series of compounds. While introduction of SO and SO2 significantly increased stability of the ketone against reduction in case of the indole-5-carboxylic acid 3, it had no effect in case of the benzotriazole 4. Further analysis of the metabolism of 3 and 4 in rat liver S9 fractions revealed that the major metabolite of 3 was the alcohol 53 formed by reduction of the keto group. In contrast, in case of 4 beside keto reduction an excessive hydroxylation of the terminal phenoxy group occurred leading to the dihydroxy compound 50. Experiments with enzyme inhibitors showed that the phenylhydroxylation of 4 was catalyzed by tranylcypromine sensitive cytochrome P450 isoforms, while the reduction of the ketone function of 3 and 4 was mainly caused by cytosolic short chain dehydrogenases

  8. Glycosylation site of the major allergen from olive tree pollen. Allergenic implications of the carbohydrate moiety.

    PubMed

    Batanero, E; Villalba, M; Rodríguez, R

    1994-01-01

    The electrophoretic analysis of purified Ole e I, the major allergen from Olea europaea pollen, reveals the presence of two main variants, glycosylated (20.0 kDa) and non-glycosylated (18.5 kDa) components. The glycosylated variant has been identified as a concanavalin A-binding glycoprotein. Its carbohydrate moiety has a molecular mass of about 1.3 kDa (5% weight of the glycosylated allergen), based on mass spectrometry analysis. Enzymatic treatment of native Ole e I with the specific glycosidase PNGase F accounts for an oligosaccharide N-linked to the polypeptide chain. This treatment does not sensibly modify the secondary structure of the protein but diminishes the affinity of the allergen for specific IgE antibodies. Tryptic digestion of Ole e I reveals the presence of a single carbohydrate-containing peptide. This peptide was recognized by the sera of hypersensitive individuals. The amino acid sequence of this peptide is Phe-Lys-Leu-Asn-Thr-Val-Asn-Gly-Thr-Thr-Arg, asparagine at the seventh being the carbohydrate attaching site. The obtained data are discussed in terms of the potential role of the sugar moiety in the allergenic activity of Ole e I.

  9. Structure and Mutagenesis of Neural Cell Adhesion Molecule Domains Evidence for Flexibility in the Placement of Polysialic Acid Attachment Sites

    SciTech Connect

    Foley, Deirdre A.; Swartzentruber, Kristin G.; Lavie, Arnon; Colley, Karen J.

    2010-11-09

    The addition of {alpha}2,8-polysialic acid to the N-glycans of the neural cell adhesion molecule, NCAM, is critical for brain development and plays roles in synaptic plasticity, learning and memory, neuronal regeneration, and the growth and invasiveness of cancer cells. Our previous work indicates that the polysialylation of two N-glycans located on the fifth immunoglobulin domain (Ig5) of NCAM requires the presence of specific sequences in the adjacent fibronectin type III repeat (FN1). To understand the relationship of these two domains, we have solved the crystal structure of the NCAM Ig5-FN1 tandem. Unexpectedly, the structure reveals that the sites of Ig5 polysialylation are on the opposite face from the FN1 residues previously found to be critical for N-glycan polysialylation, suggesting that the Ig5-FN1 domain relationship may be flexible and/or that there is flexibility in the placement of Ig5 glycosylation sites for polysialylation. To test the latter possibility, new Ig5 glycosylation sites were engineered and their polysialylation tested. We observed some flexibility in glycosylation site location for polysialylation and demonstrate that the lack of polysialylation of a glycan attached to Asn-423 may be in part related to a lack of terminal processing. The data also suggest that, although the polysialyltransferases do not require the Ig5 domain for NCAM recognition, their ability to engage with this domain is necessary for polysialylation to occur on Ig5 N-glycans.

  10. Conserved Aspartic Acid Residues Lining the Extracellular Loop I of Sodium-coupled Bile Acid Transporter ASBT Interact with Na+ and 7α-OH Moieties on the Ligand Cholestane Skeleton*

    PubMed Central

    Hussainzada, Naissan; Da Silva, Tatiana Claro; Zhang, Eric Y.; Swaan, Peter W.

    2008-01-01

    Functional contributions of residues Val-99—Ser-126 lining extracellular loop (EL) 1 of the apical sodium-dependent bile acid transporter were determined via cysteine-scanning mutagenesis, thiol modification, and in silico interpretation. Despite membrane expression for all but three constructs (S112C, Y117C, S126C), most EL1 mutants (64%) were inactivated by cysteine mutation, suggesting a functional role during sodium/bile acid co-transport. A negative charge at conserved residues Asp-120 and Asp-122 is required for transport function, whereas neutralization of charge at Asp-124 yields a functionally active transporter. D124A exerts low affinity for common bile acids except deoxycholic acid, which uniquely lacks a 7α-hydroxyl (OH) group. Overall, we conclude that (i) Asp-122 functions as a Na+ sensor, binding one of two co-transported Na+ ions, (ii) Asp-124 interacts with 7α-OH groups of bile acids, and (iii) apolar EL1 residues map to hydrophobic ligand pharmacophore features. Based on these data, we propose a comprehensive mechanistic model involving dynamic salt bridge pairs and hydrogen bonding involving multiple residues to describe sodium-dependent bile acid transporter-mediated bile acid and cation translocation. PMID:18508772

  11. Synthesis and characterization of nonconventional surfactants of aromatic amino acid-glycerol ethers: effect of the amino acid moiety on the orientation and surface properties of these soap-type amphiphiles.

    PubMed

    Varka, Evdoxia-Maria A; Heli, Maria G; Coutouli-Argyropoulou, Evdoxia; Pegiadou, Sofia A

    2006-11-06

    The synthesis, characterization, and surface properties of soap-type amphiphiles comprising alkyl chains of 10-16 carbon atoms linked through an ether group to a glycerol-amino acid hydrophilic head group is described. The surface properties of members of this series derived from histidine and tyrosine were compared with those of phenylalanine and tryptophan derivatives described previously and with those of conventional soaps. In all cases, the amino acid derivatives showed superior surface properties, and an interesting differentiation was discovered regarding the orientation of tryptophan derivatives.

  12. A New Class of Natural Glycopeptides with Sugar Moiety-dependent Antioxidant Activities derived from Ganoderma lucidum Fruiting Bodies

    PubMed Central

    Wu, Yalin; Wang, Denong

    2009-01-01

    A water-soluble glycopeptide (PGY), fractionated and purified from the aqueous extract of the fruiting bodies of Ganoderma lucidum via two-step dialysis, anion-exchange and gel permeation chromatography, was constituted of two moieties of carbohydrate and peptide. Carbohydrate characterization with component analysis, methylation analysis, periodate oxidation, Smith degradation, enzymic hydrolysis, and IR and NMR experiments demonstrated that the carbohydrate moiety possessed a backbone of approximately thirty-three (1 → 3)-linked β-D-glucopyranosyl residues, and side chains, at positions 6, of single α-L-arabinofuranosyl residues for every three Glcp residues in the main chain. On the basis of the results of amino acid composition and trypsin digestion, the peptide moiety shown to consist of Arg, Ser, Ala, and Gly in a ratio of 1:1:2:2, exhibited the sequence of Ser-Arg-[(Ala)2(Gly)2], and was O-attached to the carbohydrate moiety via Ser. To contribute toward our understanding of structure-activity relationship, a series of expected derivatives generated from PGY by trypsin digestion, debranching, and NaIO4-oxidation following reduction experiments, including PTC, DB-PGY, and PPP, were obtained. All of them, as well as PGY and reference compound (BHT), were evaluated with two conventional antioxidant testing systems of DPPH and superoxide radicals scavenging, and found to have their respective antioxidant activities in a concentration-dependent manner. Comparable radical scavenging activities observed between PTC and PGY demonstrated that the removal of Ala and Gly in peptide moiety did not result in the variation of biological functions of PGY. However, it was very interesting to note that the scavenging activity of PPP was higher for DPPH radicals with an SC50 value of 116.4 ± 5.1 μg/mL, and lower for superoxide radicals with an SC50 value of 205.2 ± 14.4 μg/mL than that of PGY with corresponding SC50 values of 133.5 ± 5.5 and 140.5 ± 7.7 μg/mL, and

  13. Attachment Disorganization.

    ERIC Educational Resources Information Center

    Solomon, Judith, Ed.; George, Carol, Ed.

    Disorganized attachment relationships were first formally identified on the basis of the anomalous behavior of some infants during laboratory separations and reunions with the parent. This book presents new research and theory on the topic of attachment disorganization, an area of investigation that is of increasing importance in the study of…

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

    NASA Astrophysics Data System (ADS)

    Cheng, T.

    2015-12-01

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

  15. Aromatic Polyimides Containing Meta-Biphenoxy Moieties

    NASA Technical Reports Server (NTRS)

    St. Clair, Terry L.; Whitley, Karen S.; Pratt, John R.

    1994-01-01

    Synthesis of two novel monomers and subsequent incorporation into aromatic polyimides yields polyimides containing meta-biphenoxy moieties exhibiting stability at high temperatures and having glass-transition temperatures lower than state-of-the-art polyimides containing para-biphenoxy moieties. Because of outstanding thermal stability, low density, resistance to radiation, electrical-insulating capability, toughness, and flexibility, linear aromatic polyimides used increasingly for applications in aerospace and electronics industries and possibly in others.

  16. Chemical analysis of surface oxygenated moieties of fluorescent carbon nanoparticles

    NASA Astrophysics Data System (ADS)

    Huang, Jie; Deming, Christopher P.; Song, Yang; Kang, Xiongwu; Zhou, Zhi-You; Chen, Shaowei

    2012-01-01

    Water-soluble carbon nanoparticles were prepared by refluxing natural gas soot in concentrated nitric acid. The surface of the resulting nanoparticles was found to be decorated with a variety of oxygenated species, as suggested by spectroscopic measurements. Back potentiometric titration of the nanoparticles was employed to quantify the coverage of carboxylic, lactonic, and phenolic moieties on the particle surface by taking advantage of their vast difference of acidity (pKa). The results were largely consistent with those reported in previous studies with other carbonaceous (nano)materials. Additionally, the presence of ortho- and para-quinone moieties on the nanoparticle surface was confirmed by selective labelling with o-phenylenediamine, as manifested in X-ray photoelectron spectroscopy, photoluminescence, and electrochemical measurements. The results further supported the arguments that the surface functional moieties that were analogous to 9,10-phenanthrenequinone were responsible for the unique photoluminescence of the nanoparticles and the emission might be regulated by surface charge state, as facilitated by the conjugated graphitic core matrix.

  17. Polysialic acid enters the cell nucleus attached to a fragment of the neural cell adhesion molecule NCAM to regulate the circadian rhythm in mouse brain.

    PubMed

    Westphal, Nina; Kleene, Ralf; Lutz, David; Theis, Thomas; Schachner, Melitta

    2016-07-01

    In the mammalian nervous system, the neural cell adhesion molecule NCAM is the major carrier of the glycan polymer polysialic acid (PSA) which confers important functions to NCAM's protein backbone. PSA attached to NCAM contributes not only to cell migration, neuritogenesis, synaptic plasticity, and behavior, but also to regulation of the circadian rhythm by yet unknown molecular mechanisms. Here, we show that a PSA-carrying transmembrane NCAM fragment enters the nucleus after stimulation of cultured neurons with surrogate NCAM ligands, a phenomenon that depends on the circadian rhythm. Enhanced nuclear import of the PSA-carrying NCAM fragment is associated with altered expression of clock-related genes, as shown by analysis of cultured neuronal cells deprived of PSA by specific enzymatic removal. In vivo, levels of nuclear PSA in different mouse brain regions depend on the circadian rhythm and clock-related gene expression in suprachiasmatic nucleus and cerebellum is affected by the presence of PSA-carrying NCAM in the cell nucleus. Our conceptually novel observations reveal that PSA attached to a transmembrane proteolytic NCAM fragment containing part of the extracellular domain enters the cell nucleus, where PSA-carrying NCAM contributes to the regulation of clock-related gene expression and of the circadian rhythm.

  18. Enzymatic amplification-free nucleic acid hybridisation sensing on nanostructured thick-film electrodes by using covalently attached methylene blue.

    PubMed

    García-González, Raquel; Costa-García, Agustín; Fernández-Abedul, M Teresa

    2015-09-01

    Amplification-free (referring to enzymatic amplification step) detection methodologies are increasing in biosensor development due to the need of faster and simpler protocols. However, for maintaining sensitivity without this step, highly detectable molecules or very sensitive detection techniques are required. The nanostructuration of transducer surfaces with carbon nanotubes (CNTs), gold nanoparticles (AuNPs) or both in nanohybrid configurations has been employed in this work for DNA hybridisation sensing purposes. Methylene blue (MB), covalently attached to single stranded DNA, (ssDNA) was incubated with a complementary sequence immobilized on nanostructured screen-printed electrodes (AuSPEs). Although CNTs can increase notoriously the signal of the marker, adsorptive properties should also be considered when bioassays are performed because non-specific adsorption (NSA) phenomena are magnified. In this work, strategies for decreasing NSA were thoroughly evaluated for the detection of Mycoplasma pneumoniae (MP) on CNTs-nanostructured screen-printed electrodes. Among them, the employ of UV-radiation or long incubation times (72h) allowed obtaining higher signals for the complementary strand with respect to the non-complementary one. The use of CNTs/AuNPs nanohybrids, together with the use of streptavidin-biotin (ST-B) interaction allows the higher differentiation (with a 3.5 ratio) in the genosensing of M. pneumoniae.

  19. A pH-responsive drug nanovehicle constructed by reversible attachment of cholesterol to PEGylated poly(l-lysine) via catechol-boronic acid ester formation.

    PubMed

    Yang, Bin; Lv, Yin; Zhu, Jing-Yi; Han, Yun-Tao; Jia, Hui-Zhen; Chen, Wei-Hai; Feng, Jun; Zhang, Xian-Zheng; Zhuo, Ren-Xi

    2014-08-01

    The present work reports the construction of a drug delivery nanovehicle via a pH-sensitive assembly strategy for improved cellular internalization and intracellular drug liberation. Through spontaneous formation of boronate linkage in physiological conditions, phenylboronic acid-modified cholesterol was able to attach onto catechol-pending methoxypoly(ethylene glycol)-block-poly(l-lysine). This comb-type polymer can self-organize into a micellar nanoconstruction that is able to effectively encapsulate poorly water-soluble agents. The blank micelles exhibited negligible in vitro cytotoxicity, yet doxorubicin (DOX)-loaded micelles could effectively induce cell death at a level comparable to free DOX. Owing to the acid-labile feature of the boronate linkage, a reduction in environmental pH from pH 7.4 to 5.0 could trigger the dissociation of the nanoconstruction, which in turn could accelerate the liberation of entrapped drugs. Importantly, the blockage of endosomal acidification in HeLa cells by NH4Cl treatment significantly decreased the nuclear uptake efficiency and cell-killing effect mediated by the DOX-loaded nanoassembly, suggesting that acid-triggered destruction of the nanoconstruction is of significant importance in enhanced drug efficacy. Moreover, confocal fluorescence microscopy and flow cytometry assay revealed the effective internalization of the nanoassemblies, and their cellular uptake exhibited a cholesterol dose-dependent profile, indicating the contribution of introduced cholesterol functionality to the transmembrane process of the nanoassembly.

  20. Ureteric Obstruction From Malignant Melanoma in Both Right Double Moiety and Left Single Moiety Ureters.

    PubMed

    March, Brayden; Calopedos, Ross John Spero; Latif, Edward; Ouyang, Rupert

    2017-02-16

    We report the first documented case of malignant melanoma obstructing ureters of both moieties of a duplex kidney and contralateral single moiety ureter in a 51-year-old male. The patient presented with fever, coryzal symptoms, and liver function test derangement several years after 2 superficial spreading melanomas were excised with clear margins. Ultrasonography demonstrated hydronephroureter in both moieties of a complete right-sided duplex kidney. Retrograde pyelograms showed bilateral hydronephroureter and filling defects in all 3 ureters. Biopsied tumor cells were positive for S100, Melan A, and HMB45. Cutaneous melanoma metastasizing to ureters is a rare phenomenon and can present a diagnostic challenge to clinicians if clinically silent.

  1. Micro- to nanostructured poly(pyrrole-nitrilotriacetic acid) films via nanosphere templates: applications to 3D enzyme attachment by affinity interactions.

    PubMed

    Cernat, Andreea; Le Goff, Alan; Holzinger, Michael; Sandulescu, Robert; Cosnier, Serge

    2014-02-01

    We report the combination of latex nanosphere lithography with electropolymerization of N-substituted pyrrole monomer bearing a nitrilotriacetic acid (NTA) moiety for the template-assisted nanostructuration of poly(pyrrole-NTA) films and their application for biomolecule immobilization. The electrodes were modified by casting latex beads (100 or 900 nm in diameter) on their surface followed by electropolymerization of the pyrrole-NTA monomer and the subsequent chelation of Cu(2+) ions. The dissolution of the nanobeads leads then to a nanostructured polymer film with increased surface. Thanks to the versatile affinity interactions between the (NTA)Cu(2+) complex and histidine- or biotin-tagged proteins, both tyrosinase and glucose oxidase were immobilized on the modified electrode. Nanostructuration of the polypyrrole via nanosphere lithography (NSL) using 900- and 100-nm latex beads allows an increase in surface concentration of enzymes anchored on the functionalized polypyrrole electrode. The nanostructured enzyme electrodes were characterized by fluorescence microscopy, 3D laser scanning confocal microscopy, and scanning electron microscopy. Electrochemical studies demonstrate the increase in the amount of immobilized biomolecules and associated biosensor performances when achieving NSL compared to conventional polymer formation without bead template. In addition, the decrease in nanobead diameter from 900 to 100 nm provides an enhancement in biosensor performance. Between biosensors based on films polymerized without nanobeads and with 100-nm nanobeads, maximum current density values increase from 4 to 56 μA cm(-2) and from 7 to 45 μA cm(-2) for biosensors based on tyrosinase and glucose oxidase, respectively.

  2. Removal and biodegradation of naphthenic acids by biochar and attached environmental biofilms in the presence of co-contaminating metals.

    PubMed

    Frankel, Mathew L; Bhuiyan, Tazul I; Veksha, Andrei; Demeter, Marc A; Layzell, David B; Helleur, Robert J; Hill, Josephine M; Turner, Raymond J

    2016-09-01

    This study evaluated the efficacy of using a combined biofilm-biochar approach to remove organic (naphthenic acids (NAs)) and inorganic (metals) contaminants from process water (OSPW) generated by Canada's oil sands mining operations. A microbial community sourced from an OSPW sample was cultured as biofilms on several carbonaceous materials. Two biochar samples, from softwood bark (SB) and Aspen wood (N3), facilitated the most microbial growth (measured by protein assays) and were used for NA removal studies performed with and without biofilms, and in the presence and absence of contaminating metals. Similar NA removal was seen in 6-day sterile N3 and SB assays (>30%), while biodegradation by SB-associated biofilms increased NA removal to 87% in the presence of metals. Metal sorption was also observed, with up to four times more immobilization of Fe, Al, and As on biofilm-associated biochar. These results suggest this combined approach may be a promising treatment for OSPW.

  3. Molecular mimicry between IL-33 and KSHV for attachment to chromatin through the H2A–H2B acidic pocket

    PubMed Central

    Roussel, Lucie; Erard, Monique; Cayrol, Corinne; Girard, Jean-Philippe

    2008-01-01

    Interleukin-33 (IL-33) is an IL-1-like ligand for the ST2 receptor that stimulates the production of Th2-associated cytokines. Recently, we showed that IL-33 is a chromatin-associated factor in the nucleus of endothelial cells in vivo. Here, we report the identification of a short IL-33 chromatin-binding peptide that shares striking similarities with a motif found in Kaposi sarcoma herpesvirus LANA (latency-associated nuclear antigen), which is responsible for the attachment of viral genomes to mitotic chromosomes. Similar to LANA, the IL-33 peptide docks into the acidic pocket formed by the H2A–H2B dimer at the nucleosomal surface and regulates chromatin compaction by promoting nucleosome–nucleosome interactions. Taken together, our data provide important new insights into the nuclear roles of IL-33, and show a unique example of molecular mimicry of a chromatin-associated cytokine by a DNA tumour virus. In addition, the data provide, to the best of our knowledge, the first demonstration of the existence of non-histone cellular factors that bind to the acidic pocket of the nucleosome. PMID:18688256

  4. Intermolecular proton transfer induced by excess electron attachment to adenine(formic acid)n (n = 2, 3) hydrogen-bonded complexes

    SciTech Connect

    Mazurkiewicz, Kamil; Haranczyk, Maciej; Storoniak, Piotr; Gutowski, Maciej S.; Rak, Janusz; Radisic, Dunja; Eustis, Soren; Wang, Di; Bowen, Kit H.

    2007-12-06

    The research described in this product was performed in part in the Environmental Molecular Sciences Laboratory, a national scientific user facility sponsored by the Department of Energy's Office of Biological and Environmental Research and located at Pacific Northwest National Laboratory. The propensity of the neutral complexes between both adenine and 9-methyladenine (A/MA) with formic acid (FA) in 1:2 and 1:3 stoichiometries to bind an excess electron was studied using photoelectron spectroscopy and quantum chemistry computational methods. Although an isolated canonical adenine does not support bound valence anions, solvation by one formic acid molecule stabilizes the excess electron on adenine. The adiabatic electron affinities of the A/MA(FA)2,3 complexes span a range of 0.8–1.23 eV indicating that the anions of 1:2 and 1:3 stoichiometries are substantially more stable than the anionic A–FA dimer (EA = 0.67 eV), which we studied previously and an attachment of electron triggers double-BFPT, confirmed at the MPW1K level of theory, in all the considered systems. Hence, the simultaneous involvement of several molecules capable of forming cyclic hydrogen bonds with adenine remarkably increases its ability to bind an excess electron. The calculated vertical detachment energies for the most stable anions correspond well with those obtained using photoelectron spectroscopy. The possible biological significance of our findings is briefly discussed.

  5. Wettability Effect of PECVD-SiOx Films on Poly(lactic acid) Induced by Oxygen Plasma on Protein Adsorption and Cell Attachment

    NASA Astrophysics Data System (ADS)

    Sarapirom, S.; Lee, J. S.; Jin, S. B.; Song, D. H.; Yu, L. D.; Han, J. G.; Chaiwong, C.

    2013-04-01

    Surface wettability is an important property of biomaterials. Silicon oxide films have a wide range of applications due to a range of the properties such as the mechanical strength and surface wettability. This paper reports effect of the surface wettability of silicon oxide (SiOx) films on protein adsorption and cell attachment and proliferation. SiOx films were deposited onto poly(lactic acid) (PLA) substrate using plasma enhanced chemical vapor deposition (PECVD). Octamethylcyclotetrasiloxane (OMCTS:Si4O4C8H24) was used as a precursor with O2 as a carrier gas. After deposition, the films were treated with O2-plasma to adapt wettability. It was found that O2-plasma enhanced the wettability of the films without changing the film thickness, while made the surface morphology slightly smoother. The polar component increased after O2-plasma treatment as observed in the contact angle measurements. The surface energy of the films was calculated by means of the Owens-Wendt method to resolve the contributions of polar and dispersive components. The chemical structure was characterized using attenuated total reflectance-Fourier transform infrared (ATR-FTIR) spectroscopy. The films were dense with a high Si-network structure. The reduced carbon content (-CHn, Si-CH3) and increased hydrogen content (-OH) of the O2-plasma treated SiOx films led to the polar components enhancing the SiOx wettability. Adsorption of bovine serum albumin (BSA) on the films was investigated by using x-ray photoelectron spectroscopy (XPS). More BSA was adsorbed onto the O2-plasma treated SiOx films. Attachment and proliferation of MC3T3-E1 mouse pre-osteoblasts and L929 mouse fibroblasts cells on the SiOx films were evaluated via MTT assay. The cells were attached more to the untreated SiOx films but proliferated more on the surface of the O2-plasma treated SiOx films depending on the cell types.

  6. Synthesis and properties of optically active nanostructured polymers bearing amino acid moieties by direct polycondensation of 4,4'-thiobis(2-tert-butyl-5-methylphenol) with chiral diacids.

    PubMed

    Mallakpour, Shadpour; Soltanian, Samaneh

    2012-06-01

    Four derivatives of N-trimellitylimido-L-amino acid (4a-4d) were prepared by the reaction of trimellitic anhydride (1) with the L-amino acids (2a-2d) in acetic acid as diacid monomers and were used with the aim to obtain a new family of amino acid based poly(ester-imide)s (PEI)s. The polymerization was performed by direct polycondensation of chiral diacids (4a-4d) with 4,4'-thiobis(2-tert-butyl-5-methylphenol) (5) in the presence of tosyl chloride (TsCl), pyridine and N,N-dimethyl formamide (DMF). Step-growth polymerization was carried out by varying the time of heating and the molar ratio of TsCl/diacid and the optimum conditions were achieved. The synthesized polymers were characterized by means of specific rotation experiments, FT-IR, 1H-NMR, X-ray diffraction techniques and elemental analysis. The surface morphology of the obtained polymers was studied by field emission scanning electron microscopy. The result showed nanostructure morphology of the resulting polymers. The obtained PEIs were soluble in polar aprotic solvents such as DMF, N,N-dimethyl acetamide, dimethyl sulfoxide, N-methyl-2-pyrrolidone and protic solvents such as sulfuric acid. Thermal stability and the weight-loss behavior of the PEIs were studied by thermal gravimetric analysis (TGA) techniques. TGA showed that the 10% weight loss temperature in a nitrogen atmosphere was more than 402°C, therefore they had useful levels of thermal stability associated with excellent solubility.

  7. Compounds having thiourea moiety as derivatization reagents in liquid chromatography/electrospray ionization-tandem mass spectrometry (LC/ESI-MS/MS): synthesis of derivatization reagents for carboxylic acids.

    PubMed

    Inoda, Hirotaka; Nishiyama, Taihei; Yoshikado, Takashi; Suwanai, Yusuke; Santa, Tomofumi

    2011-06-01

    The derivatization reagents for carboxylic acids, N-(Pyridin-3-yl)hydrazinecarbothioamide, N-[4-(dimethylamino)phenyl]hydrazinecarbothioamide, 1-(2-aminoethyl)-3-(pyridin-3-yl)thiourea, 1-(2-aminoethyl)-3-[4-(dimethylamino)phenyl]thiourea and 4-(2-aminoethyl)-N-phenylpiperazine-1-carbothioamide were synthesized. These reagents reacted with carboxylic acids at 60°C for 45 min in the presence of the condensation reagents. The generated derivatives were favorably separated on the reversed-phase column and sensitively detected by electrospray ionization tandem mass spectrometry. These reagents enhanced the electrospray ionization response of the analyte and generated a particular product ion efficiently by collision-induced dissociation, and thus they were suitable for MS/MS detection.

  8. Prosthetic iodination methods for radiolabeling of carbonyl moieties

    SciTech Connect

    Barakat, B.M.A.

    1987-01-01

    The demonstrable need for an indirect, prosthetic-group, radioiodination of carbonyl-containing biomolecules such as ketosteroids, carbohydrates, gangliosides, glycoproteins and aldehydo- and keto-drugs. This need has been addressed by developing a route to iodinated (radioiodination) aryl hydrazides which are subsequently condensed with carbonyl-containing moieties. This dissertation is directed at improving the utility of this reaction and at comparing the hydrolytic stability of the resulting hydrazones to that of similar tyramine imines, a type presently employed in indirect radioiodinations. The aryl carboxylic acid hydrazones were virtually inert to hydrolysis under simulated physiological conditions which caused imine bond rupture. Further improvements to this new prosthetic labeling method were sought in simplifying its two-step, acid-catalyzed cleavage of triazenooxadiazoles (the protected, pre-labeling form of the aryl carboxylic acid hydrazides) to the iodinated hydrazide. Synthetic procedures were explored which might yield non-conjugated aryl oxadiazoles--bearing methylenes inserted between the phenyl and the heterocyclic ring--in the expectation that these substances would be less stable and would hydrolyze in a single-acid-catalyzed step. Four synthetic pathways to amino (or nitro) aryl-methyl oxadiazoles could not be advanced beyond the open-chain precursors of the heterocyclics. Pyrolysis, thermolysis, and catalyzed cyclization reagents could not effect ring closure. A method was developed, however, to an oxadiazolone which can serve as a protective functionality for the iodinated aryl acid hydrazides.

  9. Moieties in Ancient Mesoamerica: Inferences on Teotihuacan Social Structure

    ERIC Educational Resources Information Center

    Becker, Marshall Joseph

    1975-01-01

    The intent of this article is to demonstrate the existence of political moieties at Teotihuacan by gathering evidence for dual organization in Mesoamerica, providing information regarding the operation and functions of political moieties, and indicating how the evidence now available conforms to a general model of moieties. (Author)

  10. AglC and AglK are involved in biosynthesis and attachment of diacetylated glucuronic acid to the N-glycan in Methanococcus voltae.

    PubMed

    Chaban, Bonnie; Logan, Susan M; Kelly, John F; Jarrell, Ken F

    2009-01-01

    Recent advances in the field of prokaryotic N-glycosylation have established a foundation for the pathways and proteins involved in this important posttranslational protein modification process. To continue the study of the Methanococcus voltae N-glycosylation pathway, characteristics of known eukaryotic, bacterial, and archaeal proteins involved in the N-glycosylation process were examined and used to select candidate M. voltae genes for investigation as potential glycosyl transferase and flippase components. The targeted genes were knocked out via linear gene replacement, and the resulting effects on N-glycan assembly were identified through flagellin and surface (S) layer protein glycosylation defects. This study reports the finding that deletion of two putative M. voltae glycosyl transferase genes, designated aglC (for archaeal glycosylation) and aglK, interfered with proper N-glycosylation. This resulted in flagellin and S-layer proteins with significantly reduced apparent molecular masses, loss of flagellar assembly, and absence of glycan attachment. Given previous knowledge of both the N-glycosylation pathway in M. voltae and the general characteristics of N-glycosylation components, it appears that AglC and AglK are involved in the biosynthesis or transfer of diacetylated glucuronic acid within the glycan structure. In addition, a knockout of the putative flippase candidate gene (Mv891) had no effect on N-glycosylation but did result in the production of giant cells with diameters three to four times that of wild-type cells.

  11. Cell Surface-Associated Lipoteichoic Acid Acts as an Adhesion Factor for Attachment of Lactobacillus johnsonii La1 to Human Enterocyte-Like Caco-2 Cells

    PubMed Central

    Granato, Dominique; Perotti, Fabienne; Masserey, Isabelle; Rouvet, Martine; Golliard, Mireille; Servin, Alain; Brassart, Dominique

    1999-01-01

    The influence of pH on the adhesion of two Lactobacillus strains to Caco-2 human intestinal cells was investigated. One strain, Lactobacillus johnsonii La1, was adherent at any pH between 4 and 7. The other one, L. acidophilus La10, did not attach to this cell line under the same experimental conditions. On the basis of these results, we used the monoclonal antibody technique as a tool to determine differences on the surface of these bacteria and to identify a factor for adhesion. Mice were immunized with live La1, and the hybridomas produced by fusion of spleen cells with ONS1 cells were screened for the production of antibodies specific for L. johnsonii La1. A set of these monoclonal antibodies was directed against a nonproteinaceous component of the L. johnsonii La1 surface. It was identified as lipoteichoic acid (LTA). This molecule was isolated, chemically characterized, and tested in adhesion experiments in the same system. The adhesion of L. johnsonii La1 to Caco-2 cells was inhibited in a concentration-dependent way by purified LTA as well as by L. johnsonii La1 culture supernatant that contained LTA. These results showed that the mechanism of adhesion of L. johnsonii La1 to human Caco-2 cells involves LTA. PMID:10049865

  12. Synthesis and biological evaluations of sulfa derivatives bearing heterocyclic moieties.

    PubMed

    Abdel-Monem, Wafaa R

    2004-01-01

    Some new sulfa derivatives bearing a heterocyclic moieties fural, pyrimidinone, thiazolidinone, benzimidazole and 1,2,4-triazinone and the related compounds 2-19 have been synthesized from treatment of sulfa drugs with thioisocyanate, acid chlorides, 3-chloro-1,2,4-triazines, aldehydes, esters and/or 2-methylbenzoxazole followed by ring closure reactions. Structures of the products have been deduced from their elemental analysis and spectral data. Significant antimicrobial activities were observed in vitro for some members of the series. Compounds 9b, 16 are highly active, while compounds 4b, 6d, 7,9a, 10 and 14 showing a moderate active towards gramme positive bacterium (b.subtilis). gramme negative bacterium (E. coli) and two fungi namely (A.nidulans & A.terreus).

  13. Paternal Attachment, Parenting Beliefs and Children's Attachment

    ERIC Educational Resources Information Center

    Howard, Kimberly S.

    2010-01-01

    Relationships between fathers' romantic attachment style, parenting beliefs and father-child attachment security and dependence were examined in a diverse sample of 72 fathers of young children. Paternal romantic attachment style was coded based on fathers' endorsement of a particular style represented in the Hazan and Shaver Three-Category…

  14. Polysilacage moiety as a bulky mesogenic motif

    NASA Astrophysics Data System (ADS)

    Shimizu, Masaki; Nata, Masanori; Hiyama, Tamejiro

    2008-08-01

    We found that 1-alkyl-4-phenyl-2,2,3,3,5,5,6,6,7,7,8,8-dodecamethyl-2,3,5,6,7,8-hexasilabicyclo[2.2.2]octanes exhibited hexagonal columnar phases with an alkyl group ranging from a methyl to a pentyl group. Introduction of a cyano group at para-position of the phenyl group was found to enhance the stability of the columnar phases. The observed columnar phases strikingly contrasted with a nematic phase of 1-alkyl-4-(4-cyanophenyl)bicyclo[2.2.2]octanes. Furthermore, the polysilacage derivatives with such short alkyl groups as n-propyl, n-butyl, n-pentyl, and n-hexyl at 1-position, that contain neither long alkyl groups nor aromatic rings, were also disclosed to exhibit columnar mesophases, indicating that the polysilacage moiety has a high tendency to form columnar structure.

  15. Efficiency of sodium hypochlorite, fumaric acid, and mild heat in killing native microflora and Escherichia coli O157:H7, Salmonella typhimurium DT104, and Staphylococcus aureus attached to fresh-cut lettuce.

    PubMed

    Kondo, Nozomi; Murata, Masatsune; Isshiki, Kenji

    2006-02-01

    The effect of the disinfectant sodium hypochlorite (NaClO), with or without mild heat (50 degrees C) and fumaric acid, on native bacteria and the foodborne pathogens Staphylococcus aureus, Escherichia coli O157:H7, and Salmonella Typhimurium DT104 attached to iceberg lettuce leaves was examined. The retail lettuce examined consistently harbored 6 to 7 log CFU/g of native bacteria throughout the study period. Inner leaves supported 1 to 2 log CFU/g fewer bacteria than outer leaves. About 70% of the native bacterial flora was removed by washing five times with 0.85% NaCl. S. aureus, E. coli, and Salmonella allowed to attach to lettuce leaves for 5 min were more easily removed by washing than when allowed to attach for 1 h or 2 days, with more S. aureus being removed than E. coli or Salmonella Typhimurium. An increase of time for attachment of pathogens from 5 min to 2 days leads to decreased efficiency of the washing and sanitizing treatment. Treatment with fumaric acid (50 mM for 10 min at room temperature) was the most effective, although it caused browning of the lettuce, with up to a 2-log reduction observed. The combination of 200 ppm of sodium hypochlorite and mild heat treatment at 50 degrees C for 1 min reduced the pathogen populations by 94 to 98% (1.2- to 1.7-log reduction) without increasing browning.

  16. Diamond surface functionalization with biomimicry - Amine surface tether and thiol moiety for electrochemical sensors

    NASA Astrophysics Data System (ADS)

    Sund, James B.; Causey, Corey P.; Wolter, Scott D.; Parker, Charles B.; Stoner, Brian R.; Toone, Eric J.; Glass, Jeffrey T.

    2014-05-01

    The surface of conducting diamond was functionalized with a terminal thiol group that is capable of binding and detecting nitrogen-oxygen species. The functionalization process employed multiple steps starting with doped diamond films grown by plasma enhanced chemical vapor deposition followed by hydrogen termination and photochemical attachment of a chemically protected amine alkene. The surface tether was deprotected to reveal the amine functionality, which enabled the tether to be extended with surface chemistry to add a terminal thiol moiety for electrochemical sensing applications. Each step of the process was validated using X-ray photoelectron spectroscopy analysis.

  17. Synthesis of dehydroepiandrosterone analogues modified with phosphatidic acid moiety.

    PubMed

    Smuga, Damian A; Smuga, Małgorzata; Swizdor, Alina; Panek, Anna; Wawrzeńczyk, Czesław

    2010-12-12

    Dehydroepiandrosterone (DHEA) and its metabolite 7α-OH DHEA have many diverse physiological, biological and biochemical effects encompassing various cell types, tissues and organs. In in vitro studies, DHEA analogues have myriad biological actions, but in vivo, especially in oral administration, DHEA produces far more limited clinical effects. One of the possible solutions of this problem is conversion of DHEA to active analogues and/or its transformation into prodrug form. In this article, the studies on the conversion of DHEA and 7α-OH DHEA into their phosphatides by the phosphodiester approach are described. In this esterification, N,N-dicyclohexylcarbodiimide (DCC) was the most efficient coupling agent as well as p-toluenesulphonyl chloride (TsCl).

  18. Structural Requirements of HDAC Inhibitors: SAHA Analogs Functionalized Adjacent to the Hydroxamic Acid

    PubMed Central

    Bieliauskas, Anton V.; Weerasinghe, Sujith V. W.; Pflum, Mary Kay H.

    2007-01-01

    Inhibitors of histone deacetylase (HDAC) proteins such as suberoylanilide hydroxamic acid (SAHA) have emerged as effective therapeutic anti-cancer agents. To better understand the structural requirements of HDAC inhibitors, a small molecule library with a variety of substituents attached adjacent to the metal binding hydroxamic acid of SAHA was synthesized. The presence of a substituent adjacent to the hydroxamic acid led to an 800 to 5000-fold decrease in inhibition compared to SAHA. The observed results have implications for drug design, suggesting that HDAC inhibitors with substituents near the metal binding moiety will have inhibitory activities in the μM rather than nM range. PMID:17307359

  19. Protease inhibitors, part 13: Specific, weakly basic thrombin inhibitors incorporating sulfonyl dicyandiamide moieties in their structure.

    PubMed

    Clare, B W; Scozzafava, A; Supuran, C T

    2001-01-01

    A series of compounds has been prepared by reaction of dicyandiamide with alkyl/arylsulfonyl halides as well as arylsulfonylisocyanates to locate a lead for obtaining weakly basic thrombin inhibitors with sulfonyldicyandiamide moieties as the S1 anchoring group. The detected lead was sulfanilyl-dicyandiamide (K1 of 3 microM against thrombin, and 15 microM against trypsin), which has been further derivatized at the 4-amino group by incorporating arylsulfonylureido as well as amino acyl/dipeptidyl groups protected at the amino terminal moiety with benzyloxycarbonyl or tosylureido moieties. The best compound obtained (ts-D-Phe-Pro-sulfanilyl-dicyandiamide) showed inhibition constants of 9 nM against thrombin and 1400 nM against trypsin. pKa measurements showed that the new derivatives reported here do indeed possess a reduced basicity, with the pKa of the modified guanidine moieties in the range 7.9-8.3 pKa units. Molecular mechanics calculations showed that the preferred tautomeric form of these compounds is of the type ArSO2N=C(NH2) NH-CN, probably allowing for the formation of favorable interaction between this new anchoring group and the active site amino acid residue Asp 189, critical for substrate/inhibitor binding to this type of serine protease. Thus, the main finding of the present paper is that the sulfonyldicyandiamide group may constitute an interesting alternative for obtaining weakly basic, potent thrombin inhibitors, which bind with less affinity to trypsin.

  20. Belt attachment and system

    DOEpatents

    Schneider, Abraham D.; Davidson, Erick M.

    2016-02-02

    Disclosed herein is a belt assembly including a flexible belt with an improved belt attachment. The belt attachment includes two crossbars spaced along the length of the belt. The crossbars retain bearings that allow predetermined movement in six degrees of freedom. The crossbars are connected by a rigid body that attaches to the bearings. Implements that are attached to the rigid body are simply supported but restrained in pitching rotation.

  1. Hydrophobic Moiety of Cationic Lipids Strongly Modulates Their Transfection Activity

    SciTech Connect

    Koynova, Rumiana; Tenchov, Boris; Wang, Li; MacDonald, Robert C.

    2010-01-18

    Synthetic cationic lipids are widely used components of nonviral gene carriers, and the factors regulating their transfection efficiency are the subject of considerable interest. In view of the important role that electrostatic interactions with the polyanionic nucleic acids play in formation of lipoplexes, a common empirical approach to improving transfection has been the synthesis and testing of amphiphiles with new versions of positively charged polar groups, while much less attention has been given to the role of the hydrophobic lipid moieties. On the basis of data for {approx}20 cationic phosphatidylcholine (PC) derivatives, here we demonstrate that hydrocarbon chain variations of these lipids modulate by over 2 orders of magnitude their transfection efficiency. The observed molecular structure-activity relationship manifests in well-expressed dependences of activity on two important molecular characteristics, chain unsaturation and total number of carbon atoms in the lipid chains, which is representative of the lipid hydrophobic volume and hydrophilic-lipophilic ratio. Transfection increases with decrease of chain length and increase of chain unsaturation. Maximum transfection was found for cationic PCs with monounsaturated 14:1 chains. It is of particular importance that the high-transfection lipids strongly promote cubic phase formation in zwitterionic membrane phosphatidylethanolamine (PE). These remarkable correlations point to an alternative, chain-dependent process in transfection, not related to the electrostatic cationic-anionic lipid interactions.

  2. Micellization behavior of aromatic moiety bearing hybrid fluorocarbon sulfonate surfactants.

    PubMed

    Wadekar, Mohan N; Boekhoven, Job; Jager, Wolter F; Koper, Ger J M; Picken, Stephen J

    2012-02-21

    Aggregation behavior and thermodynamic properties of two novel homologous aromatic moiety bearing hybrid fluorocarbon surfactants, sodium 2-(2-(4-ethylphenyl)-1,1,2,2-tetrafluoroethoxy)-1,1,2,2-tetrafluoroethanesulfonate (1) and sodium 2-(1,1,2,2-tetrafluoro-2-(4-vinylphenyl)ethoxy)-1,1,2,2-tetrafluoroethanesulfonate (2) were studied using surface tension measurements and isothermal titration calorimetry (ITC) in dilute aqueous solutions at room temperature. Because of the aromatic group in the hydrophobic tail, both surfactants are soluble at room temperature unlike their starting precursor, 5-iodooctafluoro-3-oxapentanesulfonate as well as several other fluorocarbon sulfonic acid salts. Moreover, the surfactant 2 has the ability that it can be polymerized once microemulsions are formed with it. The ionic conductivity measurements of 1 at five different temperatures from 288 to 313 K were carried out to study the effect of temperature on the micellization and its thermodynamics. The pseudophase separation model was applied to estimate thermodynamic quantities from conductivity data. The Gibbs energy of micellization versus temperature exhibited the characteristic U-shaped behavior with a minimum at 306 K. The micellization process was found to be largely entropy driven. Because of its hybrid structure, the entropy change of micellization for 1 was larger than what is common for hydrocarbon surfactants like SDS but less than for fully fluorinated surfactants like NaPFO. The micellization process was found to be following the entropy-enthalpy compensation phenomena.

  3. Attachment over Time.

    ERIC Educational Resources Information Center

    Lewis, Michael; Feiring, Candice; Rosenthal, Saul

    2000-01-01

    Examined continuity in attachment classification from infancy through adolescence and related it to autobiographical memories of childhood, divorce, and maladjustment in white middle-class children. Found no continuity in attachment classification from 1 to 18 years and no relation between infant attachment status and adolescent adjustment.…

  4. A single amino acid in VP2 is critical for the attachment of infectious bursal disease subviral particles to immobilized metal ions and DF-1 cells.

    PubMed

    Lai, Su-Yuan; Chang, Gary Ro-lin; Yang, Han-Jen; Lee, Cheng-Chung; Lee, Long-Huw; Vakharia, Vikram N; Wang, Min-Ying

    2014-07-01

    VP2 protein is the primary host-protective immunogen of infectious bursal disease virus (IBDV). His249 and His253 are two surface histidine residues in IBDV subviral particles (SVP), which is formed by twenty VP2 trimers when the VP2 protein of a local isolate is expressed. Here, a systemic study was performed to investigate His249 or/and His253 on self-assembly, cell attachment and immunogenicity of SVP. Point-mutagenesis of either or both histidine residues to alanine did not affect self-assembly of the SVP, but the SVP lost its Ni-NTA binding affinity when the His253 was mutated. Indirect immunofluorescence assays and inhibitory experiments also showed that His253 is essential for SVP to attach onto the DF-1 cells and to inhibit IBDV infection of DF-1 cells. Finally, enzyme-linked immunosorbent assays and chicken protection assays demonstrated that SVP with a mutation of His253 to alanine induced comparable neutralizing antibody titers in chickens as the wild-type SVP did. It was concluded that VP2's His253, a site not significant for the overall immunogenicity induced by SVP, is crucial for the binding affinity of SVP to Ni-NTA and the attachment of an IBDV host cell line. This is the first paper to decipher the role of His253 played in receptor interaction and immunogenicity.

  5. Hepatitis C virus NS3-4A serine protease inhibitors: SAR of P'2 moiety with improved potency.

    PubMed

    Arasappan, A; Njoroge, F G; Chan, T-Y; Bennett, F; Bogen, S L; Chen, K; Gu, H; Hong, L; Jao, E; Liu, Y-T; Lovey, R G; Parekh, T; Pike, R E; Pinto, P; Santhanam, B; Venkatraman, S; Vaccaro, H; Wang, H; Yang, X; Zhu, Z; Mckittrick, B; Saksena, A K; Girijavallabhan, V; Pichardo, J; Butkiewicz, N; Ingram, R; Malcolm, B; Prongay, A; Yao, N; Marten, B; Madison, V; Kemp, S; Levy, O; Lim-Wilby, M; Tamura, S; Ganguly, A K

    2005-10-01

    We have discovered that introduction of appropriate amino acid derivatives at P'2 position improved the binding potency of P3-capped alpha-ketoamide inhibitors of HCV NS3 serine protease. X-ray crystal structure of one of the inhibitors (43) bound to the protease revealed the importance of the P'2 moiety.

  6. Spithioneines A and B, Two New Bohemamine Derivatives Possessing Ergothioneine Moiety from a Marine-Derived Streptomyces spinoverrucosus

    PubMed Central

    2015-01-01

    Spithioneines A and B (1 and 2), two new bohemamine-type pyrrolizidine alkaloids possessing an unusual ergothioneine moiety, were isolated from a marine-derived Streptomyces spinoverrucosus. Their structures were elucidated by spectroscopic analysis, CD spectra, and chemical degradation and synthesis. Compounds 1 and 2 are rare natural products that incorporate the amino acid ergothioneine. PMID:26024315

  7. Indium-mediated alkynylation of sugars: synthesis of C-glycosyl compounds bearing a protected amino alcohol moiety.

    PubMed

    Ayed, Charfedinne; Palmier, Sara; Lubin-Germain, Nadège; Uziel, Jacques; Augé, Jacques

    2010-11-22

    The coupling of glycals with an alkynyl iodide bearing a protected amino alcohol moiety was achieved in the presence of metallic indium under Barbier conditions. It gave functionalized C-glycosyl compounds, precursors of C-glycosyl amino acids with α configuration.

  8. Synthesis and biological activity of substituted urea and thiourea derivatives containing 1,2,4-triazole moiety

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A series of novel thiourea and urea derivatives carrying 1,2,4-triazole moiety were synthesized and evaluated for their antifungal and larvicidal activity. Thiourea (1a-e) and urea derivatives (2a-e) were prepared by reacting 4-(aminophenyl)acetic acid with corresponding isothiocyanates and isocyana...

  9. Temperament and attachment disorders.

    PubMed

    Zeanah, Charles H; Fox, Nathan A

    2004-03-01

    Reviewed in this article is research on children with reactive attachment disorder (RAD) who exhibit specific patterns of socially aberrant behavior resulting from being maltreated or having limited opportunities to form selective attachments. There are no data explaining why 2 different patterns of the disorder, an emotionally withdrawn-inhibited pattern and an indiscriminate-disinhibited pattern, arise from similarly aberrant environments. In this article, we consider whether temperamental differences might contribute to the different manifestations of reactive attachment disorder (RAD) in the context of adverse environments. Although the association between attachment and temperament has been studied extensively and has been the subject of spirited debate within the field of child development, there are no extant data on the influence of temperament on the development of attachment disorders. We consider possible directions for research efforts designed to explore the biological underpinnings of the complex phenomenon of attachment disorders.

  10. Blade attachment assembly

    DOEpatents

    Garcia-Crespo, Andres Jose; Delvaux, John McConnell; Miller, Diane Patricia

    2016-05-03

    An assembly and method for affixing a turbomachine rotor blade to a rotor wheel are disclosed. In an embodiment, an adaptor member is provided disposed between the blade and the rotor wheel, the adaptor member including an adaptor attachment slot that is complementary to the blade attachment member, and an adaptor attachment member that is complementary to the rotor wheel attachment slot. A coverplate is provided, having a coverplate attachment member that is complementary to the rotor wheel attachment slot, and a hook for engaging the adaptor member. When assembled, the coverplate member matingly engages with the adaptor member, and retains the blade in the adaptor member, and the assembly in the rotor wheel.

  11. Attachment of 13 Types of Foodborne Bacteria to Jalapeño and Serrano Peppers and Antibacterial Effect of Roselle Calyx Extracts, Sodium Hypochlorite, Colloidal Silver, and Acetic Acid against These Foodborne Bacteria on Peppers.

    PubMed

    Rangel-Vargas, Esmeralda; Gómez-Aldapa, Carlos A; Falfan-Cortes, Reyna N; Rodríguez-Marín, María L; Godínez-Oviedo, Angélica; Acevedo-Sandoval, Otilio A; Castro-Rosas, Javier

    2017-03-01

    Chili peppers are a very important crop in Mexico. However, these peppers have been associated with Salmonella infection outbreaks in the United States, and Salmonella and diarrheagenic Escherichia coli pathotypes have been isolated from jalapeño and serrano peppers in Mexico. To decrease microbial contamination of fruits and vegetables, chemical agents are commonly used; however, chemical agents used to eliminate pathogenic bacteria on vegetables have a limited antimicrobial effect. Roselle ( Hibiscus sabdariffa ) calyces have been reported to have an antimicrobial effect on pathogenic bacteria. In the present study, the antibacterial effect of four roselle calyx extracts (water, methanol, acetone, and ethyl acetate), sodium hypochlorite, colloidal silver, and acetic acid against foodborne bacteria was evaluated on contaminated jalapeño and serrano peppers. The 13 types of foodborne bacteria evaluated were Listeria monocytogenes , Shigella flexneri , Salmonella Typhimurium, Salmonella Typhi, Salmonella Montevideo, Staphylococcus aureus , E. coli O157:H7, five E. coli pathotypes (Shiga toxin producing, enteropathogenic, enterotoxigenic, enteroinvasive, and enteroaggregative), and Vibrio cholerae O1. All 13 types attached to both pepper types, with no significant differences in attachment between jalapeño and serrano peppers. Roselle calyx extract treatment resulted in a greater reduction in levels of all foodborne bacteria than did treatment with sodium hypochlorite, colloidal silver, and acetic acid on both pepper types. Roselle calyx extracts may be a useful for disinfection of chili peppers in the field, processing plants, restaurants, and homes.

  12. Synthesis and transformations of a pyrazole containing alpha, beta-didehydro-alpha-amino acid derivatives.

    PubMed

    Vranicar, L; Pozgan, F; Polanc, S; Kocevar, M

    2003-04-01

    2H-Pyran-2-ones 1 were transformed with various hydrazines into (E)- or (Z)-alpha, beta-didehydro-alpha-amino acid (DDAA) derivatives 4 (and 7) containing a highly substituted pyrazolyl moiety attached at the beta-position. With heterocyclic hydrazines, the products 4 were accompanied also by decarboxylated enamines E-6. In order to separate (E/Z)-mixtures of acids, they were transformed to the corresponding methyl esters 9 and 10 by the application of diazomethane. Catalytic hydrogenation under high pressures with Pd/C as a catalyst resulted in the formation of racemic alanine derivatives 11.

  13. Platinum Attachments on Iron Oxide Nanoparticle Surfaces

    SciTech Connect

    Palchoudhury, Soubantika; Xu, Yaolin; An, Wei; Turner, C. H.; Bao, Yuping

    2010-04-30

    Platinum nanoparticles supported on metal oxide surfaces have shown great potential as heterogeneous catalysts to accelerate electrochemical processes, such as the oxygen reduction reaction in fuel cells. Recently, the use of magnetic supports has become a promising research topic for easy separation and recovery of catalysts using magnets, such as Pt nanoparticles supported on iron oxide nanoparticles. The attachment of Pt on iron oxide nanoparticles is limited by the wetting ability of the Pt (metal) on ceramic surfaces. A study of Pt nanoparticle attachment on iron oxide nanoparticle surfaces in an organic solvent is reported, which addresses the factors that promote or inhibit such attachment. It was discovered that the Pt attachment strongly depends on the capping molecules of the iron oxide seeds and the reaction temperature. For example, the attachment of Pt nanoparticles on oleic acid coated iron oxide nanoparticles was very challenging, because of the strong binding between the carboxylic groups and iron oxide surfaces. In contrast, when nanoparticles are coated with oleic acid/tri-n-octylphosphine oxide or oleic acid/oleylamine, a significant increase in Pt attachment was observed. Electronic structure calculations were then applied to estimate the binding energies between the capping molecules and iron ions, and the modeling results strongly support the experimental observations.

  14. Attachment Theory and Mindfulness

    ERIC Educational Resources Information Center

    Snyder, Rose; Shapiro, Shauna; Treleaven, David

    2012-01-01

    We initiate a dialog between two central areas in the field of psychology today: attachment theory/research and mindfulness studies. The impact of the early mother-infant relationship on child development has been well established in the literature, with attachment theorists having focused on the correlation between a mother's capacity for…

  15. Attachment Line Blockage Models

    NASA Technical Reports Server (NTRS)

    1995-01-01

    Photographs shows the attachment-line experiment model with fairing and fence for supersonic attachment-line experiments. The fairing is intended to eliminate the wing/fuselage juncture shock and align the flow for the streamlined fence. The streamlined fence traps the turbulent fuselage boundary layer to prevent turbulent contamination of the leading edge flow.

  16. Infant Feeding and Attachment.

    ERIC Educational Resources Information Center

    Ainsworth, Mary D. Salter; Tracy, Russel L.

    This paper has two major purposes: first, to consider how infant feeding behavior may fit into attachment theory; and second, to cite some evidence to show how an infant's early interaction with his mother in the feeding situation is related to subsequent development. It was found that sucking and rooting are precursor attachment behaviors that…

  17. Separation and Attachment

    ERIC Educational Resources Information Center

    Honig, Alice Sterling

    2005-01-01

    Developing secure attachments with babies gives them a very special gift--the foundation for good infant mental health! In this article, the author discusses how to develop secure attachments with babies. Babies who are in the care of others during the day often suffer from separations from their special adults. Thirteen "tips" to ensure that…

  18. Reactive Attachment Disorder.

    ERIC Educational Resources Information Center

    Chapman, Sue

    2002-01-01

    Written by a British parent, this case study tells the story of an adopted child who experienced many difficulties adjusting to life at home and school. It describes attachment disorder, possible causes of attachment difficulties, the bonding cycle, therapeutic parenting, and how schools can support the re-nurturing process. (Contains references.)…

  19. Temperament and Attachment Disorders

    ERIC Educational Resources Information Center

    Zeanah, Charles H.; Fox, Nathan A.

    2004-01-01

    Reviewed in this article is research on children with reactive attachment disorder (RAD) who exhibit specific patterns of socially aberrant behavior resulting from being maltreated or having limited opportunities to form selective attachments. There are no data explaining why 2 different patterns of the disorder, an emotionally withdrawn-inhibited…

  20. Transesterification catalyzed by polystyrene-supported chymotrypsin in toluene: the effect of neutralization of basic or acidic groups attaching to polystyrene resins.

    PubMed

    Ohtani, N; Inoue, Y; Kobayashi, A; Sugawara, T

    1995-10-05

    Crosslinked polystyrene resins containing a low level of either basic or acidic groups were used for supports of alpha-chymotrypsin (CT), which catalyzed the transesterification of N-acetyl-L-phenylalanine ethyl ester (AcPheOEt) with propanol in toluene. With a minimal amount of water, CT was sorbed to the resins, basic or acidic groups of which were partly or fully neutralized by several soluble acids or bases. With an increasing degree of neutralization of basic resins by free acids, the rate of disappearance of AcPheOEt was decreased, whereas the by-product formation of AcPheOH, due to hydrolysis, was considerably suppressed, compared with the ester-exchange product, AcPheOPr. The pK(a) value of the neutralizing acid was also important for both CT activity and reaction selectivity. AcPheOPr was selectively produced at a certain range of pK(a) values. On the other hand, the neutralization of acidic resins with free amines enhanced the CT activity but a strong base promoted the formation of hydrolysis product.

  1. Late-life attachment.

    PubMed

    Freitas, Mélanie; Rahioui, Hassan

    2017-03-01

    Old age is likely to cause a crisis in one's life because of the vulnerabilities it brings up, acting as stressful elements disrupting the elder's feeling of security. It leads to the activation of what is called his attachment system, consisting in attachment styles and interpersonal emotional regulation strategies. To recover a higher sense of safety, the elder would refer to his attachment figures, that is to say closed people paying attention to him, showing towards him availability and consideration. However older adults particularly see their tolerance threshold lowered, regarding an accumulation of losses (true or symbolic) and stressful events within their lifetime. In a psychological and organic exhaustion phenomenon, the risk is to wear out the interpersonal emotional regulation strategies. These are as much vulnerabilities that may increase psychiatric decompensation, including depression. To resolve the tension of this period and to found a necessary secure feeling, the elder will have to redesign the attachment links previously settled and proceed to adjustments to this new context. The need of relational closeness comes back in the elders' attachment behaviour, counting on attachment figures not only to help their loneliness or dependency, but essentially to support them in a narcissist and affective way. That is why attachment theory enlightens the late life period, such as the new challenges older adults have to face. Many studies recognize its value in understanding the transition to old age, but without proposing conceptualization. We aim first to focus on attachment conception to say how much it is relevant with elderly, and then to describe specific terms of attachment within this population in order to better understand those patients. To finish, we must think about new therapeutic proposals taking into consideration the attachment perspective for a better understanding of old age transition.

  2. [Mentalization and attachment transmission].

    PubMed

    Böhmann, Johann; Fritsch, Sophia; Lück, Monika; Stumpe, Anna; Taubner, Svenja; Vesterling, Christina

    2014-01-01

    The present study was investigating the predictive role of maternal mentalizing and general as well as depressive symptom burden for attachment security at the end of the first year on a sample of 44 mother-child-dyads from a low-risk community study. Maternal mentalizing was assessed in a multidimensional way as Reflective Functioning (off-line) and Mind-Mindedness (on-line). The design was longitudinal measuring maternal Mind-Mindedness from a videotaped mother-child-play-interaction at the age of three months. General and depressive symptom burden was assessed using the SCL-90-R when the children were nine months old. Maternal attachment and Reflective-Functioning, using the Adult-Attachment-Interview, as well as children's attachment behavior, using the Strange-Situation-Test, were investigated at the age of twelve months. Secure maternal attachment was associated with higher Reflective Functioning, higher frequency of Mind-Mindedness and lower general and depressive symptom burden. A moderation-analysis showed a statistical trend (p = .08) that the interaction of the frequency of mind-related comments, general symptom severity and maternal attachment has a predictive value for infantile attachment security. Results can be tentatively interpreted that mothers with insecure attachment who had a lower general symptom burden and who related to their three-months old babies with a high frequency of mind-related-comments were more likely to have securely attached children. Thus, results may serve as a groundwork for projects aiming to prevent the transmission of insecure attachment by strengthening maternal Mind-Mindedness and working on the reduction of maternal general symptom burden.

  3. Structural insights into the specific anti-HIV property of actinohivin: structure of its complex with the α(1–2)mannobiose moiety of gp120

    SciTech Connect

    Hoque, M. Mominul; Suzuki, Kaoru; Tsunoda, Masaru; Jiang, Jiandong; Zhang, Fang; Takahashi, Atsushi; Ohbayashi, Naomi; Zhang, Xiaoxue; Tanaka, Haruo; Ōmura, Satoshi; Takénaka, Akio

    2012-12-01

    X-ray analysis of anti-HIV actinohivin in complex with the target α(1-2)mannobiose moiety of high-mannose type glycans attached to HIV-1 gp120 reveals that the three rotamers generated with 120 rotations around the molecular pseudo-rotation axis are packed randomly in the unit cell according to the P2{sub 1}2{sub 1}2{sub 1} symmetry to exhibit an apparent space group P2{sub 1}3 as the statistical structure. However, the high-resolution X-ray structure shows the detailed interaction geometry for specific binding. Actinohivin (AH) is an actinomycete lectin with a potent specific anti-HIV activity. In order to clarify the structural evidence for its specific binding to the α(1–2)mannobiose (MB) moiety of the D1 chains of high-mannose-type glycans (HMTGs) attached to HIV-1 gp120, the crystal structure of AH in complex with MB has been determined. The AH molecule is composed of three identical structural modules, each of which has a pocket in which an MB molecule is bound adopting a bracket-shaped conformation. This conformation is stabilized through two weak C—H⋯O hydrogen bonds facilitated by the α(1–2) linkage. The binding features in the three pockets are quite similar to each other, in accordance with the molecular pseudo-threefold symmetry generated from the three tandem repeats in the amino-acid sequence. The shape of the pocket can accept two neighbouring hydroxyl groups of the O{sup 3} and O{sup 4} atoms of the equatorial configuration of the second mannose residue. To recognize these atoms through hydrogen bonds, an Asp residue is located at the bottom of each pocket. Tyr and Leu residues seem to block the movement of the MB molecules. Furthermore, the O{sup 1} atom of the axial configuration of the second mannose residue protrudes from each pocket into an open space surrounded by the conserved hydrophobic residues, suggesting an additional binding site for the third mannose residue of the branched D1 chain of HMTGs. These structural features

  4. DNA attachment to support structures

    DOEpatents

    Balhorn, Rodney L.; Barry, Christopher H.

    2002-01-01

    Microscopic beads or other structures are attached to nucleic acids (DNA) using a terminal transferase. The transferase adds labeled dideoxy nucleotide bases to the ends of linear strands of DNA. The labels, such as the antigens digoxigenin and biotin, bind to the antibody compounds or other appropriate complementary ligands, which are bound to the microscopic beads or other support structures. The method does not require the synthesis of a synthetic oligonucleotide probe. The method can be used to tag or label DNA even when the DNA has an unknown sequence, has blunt ends, or is a very large fragment (e.g., >500 kilobase pairs).

  5. Photon Induced Electron Attachment.

    DTIC Science & Technology

    1984-12-01

    initial measure- ments was that high switch currents and long pulse durations appear to lead to substantially enhanced attachment rates in C3F8 ...similar conditions, but with 1.9 x 1015 C3F8 molecules/cm 3 added to the switch gas mixture. The initial current rise is comparable in both plots, but the...enhanced attachment during the switch opening time period. B. C0O Laser Excitation The photon enhanced attachment of the three gases NF3, C3F8 I and

  6. The neurobiology of attachment.

    PubMed

    Insel, T R; Young, L J

    2001-02-01

    It is difficult to think of any behavioural process that is more intrinsically important to us than attachment. Feeding, sleeping and locomotion are all necessary for survival, but humans are, as Baruch Spinoza famously noted, "a social animal" and it is our social attachments that we live for. Over the past decade, studies in a range of vertebrates, including humans, have begun to address the neural basis of attachment at a molecular, cellular and systems level. This review describes some of the important insights from this work.

  7. Polyimides containing meta-biphenylenedioxy moieties and articles prepared therefrom

    NASA Technical Reports Server (NTRS)

    St.clair, Terry L. (Inventor); Pratt, Richard (Inventor)

    1995-01-01

    Two monomers containing meta-biphenylenedioxy moieties were prepared. One monomer, a diamine, is used to prepare polyimide, polyamide, and epoxy polymers. The other monomer, a dianhydride, was used to prepared polyimide polymers. These polymers are used to make films, coatings, and selective membranes.

  8. Mirror Attachment For Borescope

    NASA Technical Reports Server (NTRS)

    Gearhart, John F.; Peloquin, James E.

    1994-01-01

    Attachment for articulated borescope provides views into small, normally inaccessible spaces. Simple small round mirror on extension arm welded to borescope head. Tilted at angle to axis of borescope head, mirror provides views sideways to borescope head. Disassembly of turbopump blades not necessary to enable fluorescent-penetrant-dye inspection. Attachment used to inspect difficult-to-reach internal parts of other assemblies. Also used for inspection with ordinary white light.

  9. Micromechanical die attachment surcharge

    DOEpatents

    Filter, William F.; Hohimer, John P.

    2002-01-01

    An attachment structure is disclosed for attaching a die to a supporting substrate without the use of adhesives or solder. The attachment structure, which can be formed by micromachining, functions purely mechanically in utilizing a plurality of shaped pillars (e.g. round, square or polygonal and solid, hollow or slotted) that are formed on one of the die or supporting substrate and which can be urged into contact with various types of mating structures including other pillars, a deformable layer or a plurality of receptacles that are formed on the other of the die or supporting substrate, thereby forming a friction bond that holds the die to the supporting substrate. The attachment structure can further include an alignment structure for precise positioning of the die and supporting substrate to facilitate mounting the die to the supporting substrate. The attachment structure has applications for mounting semiconductor die containing a microelectromechanical (MEM) device, a microsensor or an integrated circuit (IC), and can be used to form a multichip module. The attachment structure is particularly useful for mounting die containing released MEM devices since these devices are fragile and can otherwise be damaged or degraded by adhesive or solder mounting.

  10. Isoxazole moiety in the linker region of HDAC inhibitors adjacent to the Zn-chelating group: effects on HDAC biology and antiproliferative activity.

    PubMed

    Tapadar, Subhasish; He, Rong; Luchini, Doris N; Billadeau, Daniel D; Kozikowski, Alan P

    2009-06-01

    A series of hydroxamic acid based histone deacetylase inhibitors 6-15, containing an isoxazole moiety adjacent to the Zn-chelating hydroxamic acid, is reported herein. Some of these compounds showed nanomolar activity in the HDAC isoform inhibitory assay and exhibited micro molar inhibitory activity against five pancreatic cancer cell lines.

  11. Accumulation of medium-chain, saturated fatty acyl moieties in seed oils of transgenic Camelina sativa.

    PubMed

    Hu, Zhaohui; Wu, Qian; Dalal, Jyoti; Vasani, Naresh; Lopez, Harry O; Sederoff, Heike W; Qu, Rongda

    2017-01-01

    With its high seed oil content, the mustard family plant Camelina sativa has gained attention as a potential biofuel source. As a bioenergy crop, camelina has many advantages. It grows on marginal land with low demand for water and fertilizer, has a relatively short life cycle, and is stress tolerant. As most other crop seed oils, camelina seed triacylglycerols (TAGs) consist of mostly long, unsaturated fatty acyl moieties, which is not desirable for biofuel processing. In our efforts to produce shorter, saturated chain fatty acyl moieties in camelina seed oil for conversion to jet fuel, a 12:0-acyl-carrier thioesterase gene, UcFATB1, from California bay (Umbellularia californica Nutt.) was expressed in camelina seeds. Up to 40% of short chain laurate (C12:0) and myristate (C14:0) were present in TAGs of the seed oil of the transgenics. The total oil content and germination rate of the transgenic seeds were not affected. Analysis of positions of these two fatty acyl moieties in TAGs indicated that they were present at the sn-1 and sn-3 positions, but not sn-2, on the TAGs. Suppression of the camelina KASII genes by RNAi constructs led to higher accumulation of palmitate (C16:0), from 7.5% up to 28.5%, and further reduction of longer, unsaturated fatty acids in seed TAGs. Co-transformation of camelina with both constructs resulted in enhanced accumulation of all three medium-chain, saturated fatty acids in camelina seed oils. Our results show that a California bay gene can be successfully used to modify the oil composition in camelina seed and present a new biological alternative for jet fuel production.

  12. Accumulation of medium-chain, saturated fatty acyl moieties in seed oils of transgenic Camelina sativa

    PubMed Central

    Dalal, Jyoti; Vasani, Naresh; Lopez, Harry O.; Sederoff, Heike W.

    2017-01-01

    With its high seed oil content, the mustard family plant Camelina sativa has gained attention as a potential biofuel source. As a bioenergy crop, camelina has many advantages. It grows on marginal land with low demand for water and fertilizer, has a relatively short life cycle, and is stress tolerant. As most other crop seed oils, camelina seed triacylglycerols (TAGs) consist of mostly long, unsaturated fatty acyl moieties, which is not desirable for biofuel processing. In our efforts to produce shorter, saturated chain fatty acyl moieties in camelina seed oil for conversion to jet fuel, a 12:0-acyl-carrier thioesterase gene, UcFATB1, from California bay (Umbellularia californica Nutt.) was expressed in camelina seeds. Up to 40% of short chain laurate (C12:0) and myristate (C14:0) were present in TAGs of the seed oil of the transgenics. The total oil content and germination rate of the transgenic seeds were not affected. Analysis of positions of these two fatty acyl moieties in TAGs indicated that they were present at the sn-1 and sn-3 positions, but not sn-2, on the TAGs. Suppression of the camelina KASII genes by RNAi constructs led to higher accumulation of palmitate (C16:0), from 7.5% up to 28.5%, and further reduction of longer, unsaturated fatty acids in seed TAGs. Co-transformation of camelina with both constructs resulted in enhanced accumulation of all three medium-chain, saturated fatty acids in camelina seed oils. Our results show that a California bay gene can be successfully used to modify the oil composition in camelina seed and present a new biological alternative for jet fuel production. PMID:28212406

  13. Phosphorescence detection of L-ascorbic acid with surface-attached N-acetyl-L-cysteine and L-cysteine Mn doped ZnS quantum dots.

    PubMed

    Bian, Wei; Ma, Jing; Guo, Wenrong; Lu, Dongtao; Fan, Meng; Wei, Yanli; Li, Yingfu; Shuang, Shaomin; Choi, Martin M F

    2013-11-15

    N-Acetyl-L-cysteine (NAC) and L-cysteine (Cys) capped Mn doped ZnS quantum dots (NAC-Mn/ZnS QDs and Cys-Mn/ZnS QDs) are firstly prepared by hydrothermal methods. These QDs display strong phosphorescence emission peaks at 583 and 580 nm upon excitation at 315 and 306 nm, respectively. Since their room-temperature phosphorescence is efficiently quenched by L-ascorbic acid (AA), they have been employed as phosphorescence probes for detecting AA. The linear working ranges are 2.5-37.5 and 2.5-47.5 µM and the limits of detection are 0.72 and 1.38 µM for NAC-Mn/ZnS QDs and Cys-Mn/ZnS QDs, respectively. The possible quenching mechanisms have been discussed in detail. The QDs probes are highly selective to AA over other common ions, amino acids, glucose and bovine serum album. Finally, they have been applied successfully for detection of AA in human urine samples with satisfactory results. The recoveries are 98-104%. Our work provides a simple and convenient phosphorescence method to determine AA in real samples.

  14. Autism and Attachment: The Attachment Q-Sort

    ERIC Educational Resources Information Center

    Rutgers, Anna H.; Van Ijzendoorn, Marinus H.; Bakermans-Kranenburg, Marian J.; Swinkels, Sophie H. N.

    2007-01-01

    Children with autism are able to show secure attachment behaviours to their parents/caregivers. Most studies on attachment in children with autism used a (modified) Strange Situation Procedure (SSP) to examine attachment security. An advantage of the Attachment Q-Sort (AQS) over the SSP is that it can be attuned to the secure-base behaviour of…

  15. Reactive attachment disorder.

    PubMed

    Hornor, Gail

    2008-01-01

    Child abuse and neglect affects the lives of many American children and can result in physical injury and disability as well as psychological trauma. Reactive attachment disorder (RAD) is one possible psychological consequence of child abuse and neglect for very young children, younger than 5 years of age. RAD is described as markedly disturbed and developmentally inappropriate social relatedness usually beginning before age 5 years. These behavioral manifestations are the direct result of and come after pathogenic care. To better understand RAD, it is first necessary to understand attachment; therefore, attachment theory is examined. Risk factors for the development of RAD are presented. Implications for pediatric nurse practitioner practice are explored. The pediatric nurse practitioner can play a vital role in recognizing RAD and ensuring that children with this disorder receive prompt mental health assessment and therapy.

  16. Ceramic blade attachment system

    DOEpatents

    Boyd, Gary L.

    1994-01-01

    A turbine blade having a preestablished rate of thermal expansion is attached to a turbine wheel having a preestablished rate of thermal expansion being greater than the preestablished rate of thermal expansion of the turbine blade. The turbine blade has a root portion having a pair of recessed portions thereon. The turbine wheel includes a plurality of openings in which the turbine blade is positioned. Each of the openings have a pair of grooves therein in which are positioned a pair of pins having a generally rectangular cross-section and a reaction surface thereon. A pair of cylindrical rollers interposed respective ones of the pair of reaction surfaces and the pair of recessed portions. The attachment system or turbine assembly provides an economical, reliable and effective attachment of a component having a preestablished rate of thermal expansion to a component having a greater preestablished rate of thermal expansion.

  17. Ceramic blade attachment system

    DOEpatents

    Boyd, G.L.

    1994-12-13

    A turbine blade having a preestablished rate of thermal expansion is attached to a turbine wheel having a preestablished rate of thermal expansion being greater than the preestablished rate of thermal expansion of the turbine blade. The turbine blade has a root portion having a pair of recessed portions thereon. The turbine wheel includes a plurality of openings in which the turbine blade is positioned. Each of the openings have a pair of grooves therein in which are positioned a pair of pins having a generally rectangular cross-section and a reaction surface thereon. A pair of cylindrical rollers interposed respective ones of the pair of reaction surfaces and the pair of recessed portions. The attachment system or turbine assembly provides an economical, reliable and effective attachment of a component having a preestablished rate of thermal expansion to a component having a greater preestablished rate of thermal expansion. 3 figures.

  18. Perfluorooctanoic acid and environmental risks

    EPA Science Inventory

    Perfluorooctanoic acid (PFOA) is a member of the perfluoroalkyl acids (PFAA) family of chemicals, which consist of a carbon backbone typically four to fourteen carbons in length and a charged functional moiety.

  19. Ladder attachment platform

    DOEpatents

    Swygert,; Richard, W [Springfield, SC

    2012-08-28

    A ladder attachment platform is provided that includes a base for attachment to a ladder that has first and second side rails and a plurality of rungs that extend between in a lateral direction. Also included is a user platform for having a user stand thereon that is carried by the base. The user platform may be positioned with respect to the ladder so that it is not located between a first plane that extends through the first side rail and is perpendicular to the lateral direction and a second plane that extends through the second side rail and is perpendicular to the lateral direction.

  20. Internal pipe attachment mechanism

    DOEpatents

    Bast, R.M.; Chesnut, D.A.; Henning, C.D.; Lennon, J.P.; Pastrnak, J.W.; Smith, J.A.

    1994-12-13

    An attachment mechanism is described for repairing or extending fluid carrying pipes, casings, conduits, etc. utilizing one-way motion of spring tempered fingers to provide a mechanical connection between the attachment mechanism and the pipe. The spring tempered fingers flex to permit insertion into a pipe to a desired insertion depth. The mechanical connection is accomplished by reversing the insertion motion and the mechanical leverage in the fingers forces them outwardly against the inner wall of the pipe. A seal is generated by crushing a sealing assembly by the action of setting the mechanical connection. 6 figures.

  1. Internal pipe attachment mechanism

    DOEpatents

    Bast, Richard M.; Chesnut, Dwayne A.; Henning, Carl D.; Lennon, Joseph P.; Pastrnak, John W.; Smith, Joseph A.

    1994-01-01

    An attachment mechanism for repairing or extending fluid carrying pipes, casings, conduits, etc. utilizing one-way motion of spring tempered fingers to provide a mechanical connection between the attachment mechanism and the pipe. The spring tempered fingers flex to permit insertion into a pipe to a desired insertion depth. The mechanical connection is accomplished by reversing the insertion motion and the mechanical leverage in the fingers forces them outwardly against the inner wall of the pipe. A seal is generated by crushing a sealing assembly by the action of setting the mechanical connection.

  2. Magnetically attached sputter targets

    DOEpatents

    Makowiecki, D.M.; McKernan, M.A.

    1994-02-15

    An improved method and assembly for attaching sputtering targets to cathode assemblies of sputtering systems which includes a magnetically permeable material is described. The magnetically permeable material is imbedded in a target base that is brazed, welded, or soldered to the sputter target, or is mechanically retained in the target material. Target attachment to the cathode is achieved by virtue of the permanent magnets and/or the pole pieces in the cathode assembly that create magnetic flux lines adjacent to the backing plate, which strongly attract the magnetically permeable material in the target assembly. 11 figures.

  3. Magnetically attached sputter targets

    DOEpatents

    Makowiecki, Daniel M.; McKernan, Mark A.

    1994-01-01

    An improved method and assembly for attaching sputtering targets to cathode assemblies of sputtering systems which includes a magnetically permeable material. The magnetically permeable material is imbedded in a target base that is brazed, welded, or soldered to the sputter target, or is mechanically retained in the target material. Target attachment to the cathode is achieved by virtue of the permanent magnets and/or the pole pieces in the cathode assembly that create magnetic flux lines adjacent to the backing plate, which strongly attract the magnetically permeable material in the target assembly.

  4. Reactions of nitroxides 15. Cinnamates bearing a nitroxyl moiety synthesized using a Mizoroki-Heck cross-coupling reaction.

    PubMed

    Zakrzewski, Jerzy; Huras, Bogumiła

    2015-01-01

    Cinnamic acid derivatives bearing a nitroxyl moiety (2,2,6,6-tetramethyl-1-oxyl-4-piperidyl 3-E-aryl acrylates) were synthesized in 30-100% yield using a Mizoroki-Heck cross-coupling reaction between 4-acryloyloxy-2,2,6,6-tetramethylpiperidine-1-oxyl and iodobenzene derivatives in the presence of palladium(II) acetate coordinated with a tri(o-tolyl)phosphine ligand immobilized in a polyurea matrix.

  5. Reactions of nitroxides 15. Cinnamates bearing a nitroxyl moiety synthesized using a Mizoroki–Heck cross-coupling reaction

    PubMed Central

    Huras, Bogumiła

    2015-01-01

    Summary Cinnamic acid derivatives bearing a nitroxyl moiety (2,2,6,6-tetramethyl-1-oxyl-4-piperidyl 3-E-aryl acrylates) were synthesized in 30–100% yield using a Mizoroki–Heck cross-coupling reaction between 4-acryloyloxy-2,2,6,6-tetramethylpiperidine-1-oxyl and iodobenzene derivatives in the presence of palladium(II) acetate coordinated with a tri(o-tolyl)phosphine ligand immobilized in a polyurea matrix. PMID:26199672

  6. A new 3,4-seco-oleanane-type triterpenoid with an unusual enedione moiety from Hypericum ascyron.

    PubMed

    Chen, Chunmei; Wei, Guangzheng; Zhu, Hucheng; Guo, Yi; Li, Xiao-Nian; Zhang, Jinwen; Liu, Yanfei; Yao, Guangmin; Luo, Zengwei; Xue, Yongbo; Zhang, Yonghui

    2015-06-01

    A novel 3,4-seco-oleanane-type triterpenoid named 3,4-seco-olean-13(18)-ene-12,19-dione-3-oic acid (1), bearing an unusual enedione moiety, was isolated from the aerial parts of Hypericum ascyron, together with a known feiedelane-type triterpenoid friedelin (2). The structure of 1 with absolute configuration was elucidated on the basis of spectroscopic methods and a single-crystal X-ray diffraction analysis.

  7. Selectivity of the cleavage/attachment site of phosphatidylinositol-glycan-anchored membrane proteins determined by site-specific mutagenesis at Asp-484 of placental alkaline phosphatase.

    PubMed Central

    Micanovic, R; Gerber, L D; Berger, J; Kodukula, K; Udenfriend, S

    1990-01-01

    Many proteins are now known to be anchored to the plasma membrane by a phosphatidylinositol-glycan (PI-G) moiety that is attached to their COOH termini. Placental alkaline phosphatase (PLAP) has been used as a model for investigating mechanisms involved in the COOH-terminal processing of PI-G-tailed proteins. The COOH-terminal domain of pre-pro-PLAP provides a signal for processing during which a largely hydrophobic 29-residue COOH-terminal peptide is removed, and the PI-G moiety is added to the newly exposed Asp-484 terminus. This cleavage/attachment site was subjected to an almost saturation mutagenesis, and the enzymatic activities, COOH-terminal processing, and cellular localizations of the various mutant PLAP forms were determined. Substitution of Asp-484 by glycine, alanine, cysteine, asparagine, or serine (category I) resulted in PI-G-tailed and enzymatically active proteins. However, not all category I mutant proteins were PI-G tailed to the same extent. Pre-pro-PLAP with other substituents at position 484 (threonine, proline, methionine, valine, leucine, tyrosine, tryptophan, lysine, glutamic acid, and glutamine; category II) were expressed, as well as the category I amino acids, but there was little or no processing to the PI-G-tailed form, and this latter group exhibited very low enzyme activity. The bulk of the PLAP protein produced by category II mutants and some produced by category I mutants were sequestered within the cell, apparently in the endoplasmic reticulum (ER). Most likely, certain amino acids at residue 484 are preferred because they yield better substrates for the putative "transamidating" enzyme. In transfected COS cells, at least, posttranslational PI-G-tail processing does not go to completion even for preferred substrates. Apparently PI-G tailing is a requisite for transport from the ER and for PLAP enzyme activity. Proteins that are not transamidated are apparently retained in the ER in an inactive conformation. Images PMID:2153284

  8. Controlled radical polymerization of an acrylamide containing L-alanine moiety via ATRP.

    PubMed

    Rafiee, Zahra

    2016-02-01

    Homopolymerization of an optically active acrylamide having an amino acid moiety in the side chain, N-acryloyl-L-alanine (AAla) was carried out via atom transfer radical polymerization (ATRP) at room temperature using 2-hydroxyethyl-2'-methyl-2'-bromopropionate (HMB) or sodium-4-(bromomethyl)benzoate (SBB) as initiator in pure water, methanol/water mixture and pure methanol solvents. The polymerization reaction resulted in the optically active biocompatible amino acid-based homopolymer in good yield with narrow molecular weight distribution. The number average molecular weight increased with conversion and polydispersity was low. The structure and molecular weight of synthesized polymer were characterized by (1)H NMR, FT-IR spectroscopic techniques and size-exclusion chromatography.

  9. Bacterial attachment to polymeric materials correlates with molecular flexibility and hydrophilicity.

    PubMed

    Sanni, Olutoba; Chang, Chien-Yi; Anderson, Daniel G; Langer, Robert; Davies, Martyn C; Williams, Philip M; Williams, Paul; Alexander, Morgan R; Hook, Andrew L

    2015-04-02

    A new class of material resistant to bacterial attachment has been discovered that is formed from polyacrylates with hydrocarbon pendant groups. In this study, the relationship between the nature of the hydrocarbon moiety and resistance to bacteria is explored, comparing cyclic, aromatic, and linear chemical groups. A correlation is shown between bacterial attachment and a parameter derived from the partition coefficient and the number of rotatable bonds of the materials' pendant groups. This correlation is applicable to 86% of the hydrocarbon pendant moieties surveyed, quantitatively supporting the previous qualitative observation that bacteria are repelled from poly(meth)acrylates containing a hydrophilic ester group when the pendant group is both rigid and hydrophobic. This insight will help inform and predict the further development of polymers resistant to bacterial attachment.

  10. Bacterial Attachment to Polymeric Materials Correlates with Molecular Flexibility and Hydrophilicity

    PubMed Central

    Sanni, Olutoba; Chang, Chien-Yi; Anderson, Daniel G; Langer, Robert; Davies, Martyn C; Williams, Philip M; Williams, Paul; Alexander, Morgan R; Hook*, Andrew L

    2015-01-01

    A new class of material resistant to bacterial attachment has been discovered that is formed from polyacrylates with hydrocarbon pendant groups. In this study, the relationship between the nature of the hydrocarbon moiety and resistance to bacteria is explored, comparing cyclic, aromatic, and linear chemical groups. A correlation is shown between bacterial attachment and a parameter derived from the partition coefficient and the number of rotatable bonds of the materials' pendant groups. This correlation is applicable to 86% of the hydrocarbon pendant moieties surveyed, quantitatively supporting the previous qualitative observation that bacteria are repelled from poly(meth)acrylates containing a hydrophilic ester group when the pendant group is both rigid and hydrophobic. This insight will help inform and predict the further development of polymers resistant to bacterial attachment. PMID:25491266

  11. Multisite clickable modification of proteins using lipoic acid ligase.

    PubMed

    Plaks, Joseph G; Falatach, Rebecca; Kastantin, Mark; Berberich, Jason A; Kaar, Joel L

    2015-06-17

    Approaches that allow bioorthogonal and, in turn, site-specific chemical modification of proteins present considerable opportunities for modulating protein activity and stability. However, the development of such approaches that enable site-selective modification of proteins at multiple positions, including internal sites within a protein, has remained elusive. To overcome this void, we have developed an enzymatic approach for multisite clickable modification based on the incorporation of azide moieties in proteins using lipoic acid ligase (LplA). The ligation of azide moieties to the model protein, green fluorescent protein (GFP), at the N-terminus and two internal sites using lipoic acid ligase was shown to proceed efficiently with near-complete conversion. Modification of the ligated azide groups with poly(ethylene glycol) (PEG), α-d-mannopyranoside, and palmitic acid resulted in highly homogeneous populations of protein-polymer, protein-sugar, and protein-fatty acid conjugates. The homogeneity of the conjugates was confirmed by mass spectrometry (MALDI-TOF) and SDS-PAGE electrophoresis. In the case of PEG attachment, which involved the use of strain-promoted azide-alkyne click chemistry, the conjugation reaction resulted in highly homogeneous PEG-GFP conjugates in less than 30 min. As further demonstration of the utility of this approach, ligated GFP was also covalently immobilized on alkyne-terminated self-assembled monolayers. These results underscore the potential of this approach for, among other applications, site-specific multipoint protein PEGylation, glycosylation, fatty acid modification, and protein immobilization.

  12. Enhanced Aqueous Solubility of Long Wavelength Voltage-Sensitive Dyes by Covalent Attachment of Polyethylene Glycol

    PubMed Central

    Patrick, Michael J.; Ernst, Lauren A.; Waggoner, Alan S.; Thai, Dung; Salama, Guy

    2011-01-01

    Long wavelength voltage-sensitive dyes (VSDs) called Pittsburgh (PGH) dyes were recently synthesized by coupling various heterocyclic groups to a styryl-thiophene intermediate forming extended, partially rigidized chromophores. Unlike most styryl VSDs, dyes with a sulfonic acid anchor directly attached to the chromophore showed no solvatochromic absorption shifts. The limited water solubility of many long wavelength VSDs requires the use of surfactants to transport the dye through aqueous media and effectively label biological membranes. Here, we tested the chemical substitution of the sulfonic acid moiety with polyethyleneglycol (PEG) chains ranging from MW 750 to 5000, to overcome the poor solubility of VSDs while retaining their properties as VSDs. The chemical synthesis of PGH dyes and their PEG derivatives are described. The PEG-derivatives were soluble in aqueous solutions (> 1 mM) and still reported membrane potential changes. In frog and mouse hearts, the voltage sensitivity (ΔF/F per action potential) and spectral properties of PEG dyes were the same as the sulfonated analogs. Thus, the solubility of VSDs can be considerably improved with small polyethyleneglycol chains and can provide an effective approach to improve staining of excitable tissues and optical recordings of membrane potential. PMID:17912389

  13. Folic acid-mediated targeting of cowpea mosaic virus particles to tumor cells

    PubMed Central

    Destito, Giuseppe; Yeh, Robert; Rae, Chris S.; Finn, M. G.; Manchester, Marianne

    2007-01-01

    Summary Cowpea mosaic virus (CPMV) is a well-characterized nanoparticle that has been used for a variety of nanobiotechnology applications. CPMV interacts with several mammalian cell lines and tissues in vivo. To overcome natural CPMV targeting and re-direct CPMV particles to cells of interest, we attached a novel folic acid-PEG conjugate using the copper-catalyzed azide-alkyne cycloaddition reaction. PEGylation of CPMV completely eliminated background binding of the virus to tumor cells. The PEG-folate moiety allowed CPMV specific recognition of tumor cells bearing the folate receptor. In addition, by testing CPMV formulations with different amounts of the PEG-FA moiety displayed on the surface, we show that higher-density loading of targeting ligands on CPMV may not be necessary for efficient targeting to tumor cells. These studies help to define the requirements for efficiently targeting nanoparticles and protein cages to tumors. PMID:17961827

  14. Binding of amphiphilic and triphilic block copolymers to lipid model membranes: the role of perfluorinated moieties.

    PubMed

    Schwieger, Christian; Achilles, Anja; Scholz, Sven; Rüger, Jan; Bacia, Kirsten; Saalwaechter, Kay; Kressler, Jörg; Blume, Alfred

    2014-09-07

    A novel class of symmetric amphi- and triphilic (hydrophilic, lipophilic, fluorophilic) block copolymers has been investigated with respect to their interactions with lipid membranes. The amphiphilic triblock copolymer has the structure PGMA(20)-PPO(34)-PGMA(20) (GP) and it becomes triphilic after attaching perfluoroalkyl moieties (F9) to either end which leads to F(9)-PGMA(20)-PPO(34)-PGMA(20)-F(9) (F-GP). The hydrophobic poly(propylene oxide) (PPO) block is sufficiently long to span a lipid bilayer. The poly(glycerol monomethacrylate) (PGMA) blocks have a high propensity for hydrogen bonding. The hydrophobic and lipophobic perfluoroalkyl moieties have the tendency to phase segregate in aqueous as well as in hydrocarbon environments. We performed differential scanning calorimetry (DSC) measurements on polymer bound lipid vesicles under systematic variation of the bilayer thickness, the nature of the lipid headgroup, and the polymer concentration. The vesicles were composed of phosphatidylcholines (DMPC, DPPC, DAPC, DSPC) or phosphatidylethanolamines (DMPE, DPPE, POPE). We showed that GP as well as F-GP binding have membrane stabilizing and destabilizing components. PPO and F9 blocks insert into the hydrophobic part of the membrane concomitantly with PGMA block adsorption to the lipid headgroup layer. The F9 chains act as additional membrane anchors. The insertion of the PPO blocks of both GP and F-GP could be proven by 2D-NOESY NMR spectroscopy. By fluorescence microscopy we show that F-GP binding increases the porosity of POPC giant unilamellar vesicles (GUVs), allowing the influx of water soluble dyes as well as the translocation of the complete triphilic polymer and its accumulation at the GUV surface. These results open a new route for the rational design of membrane systems with specific properties.

  15. Day Care and Attachment

    ERIC Educational Resources Information Center

    Portnoy, Fern C.; Simmons, Carolyn H.

    1978-01-01

    The attachment behavior of 35 white, middle-class 3 1/2- to 4-year-olds who had experienced different rearing histories was observed through a series of standardized episodes involving separations and reunions with the mother and a stranger. (Author/JMB)

  16. Attachment and Personality Disorders

    ERIC Educational Resources Information Center

    Sinha, Preeti; Sharan, Pratap

    2007-01-01

    Personality disorders (PDs) arise from core psychopathology of interpersonal relationships and understanding of self and others. The distorted representations of self and others, as well as unhealthy relationships that characterize persons with various PDs, indicate the possibility that persons with PDs have insecure attachment. Insecure…

  17. Amino acid analogs for tumor imaging

    DOEpatents

    Goodman, Mark M.; Shoup, Timothy

    1998-10-06

    The invention provides novel amino acid compounds of use in detecting and evaluating brain and body tumors. These compounds combine the advantageous properties of 1-amino-cycloalkyl-1-carboxylic acids, namely, their rapid uptake and prolonged retention in tumors with the properties of halogen substituents, including certain useful halogen isotopes including fluorine-18, iodine-123, iodine-125, iodine-131, bromine-75, bromine-76, bromine-77 and bromine-82. In one aspect, the invention features amino acid compounds that have a high specificity for target sites when administered to a subject in vivo. Preferred amino acid compounds show a target to non-target ratio of at least 5:1, are stable in vivo and substantially localized to target within 1 hour after administration. An especially preferred amino acid compound is ›.sup.18 F!-1-amino-3-fluorocyclobutane-1-carboxylic acid (FACBC). In another aspect, the invention features pharmaceutical compositions comprised of an .alpha.-amino acid moiety attached to either a four, five, or a six member carbon-chain ring. In addition, the invention features analogs of .alpha.-aminoisobutyric acid.

  18. Amino acid analogs for tumor imaging

    DOEpatents

    Goodman, Mark M.; Shoup, Timothy

    1998-09-15

    The invention provides novel amino acid compounds of use in detecting and evaluating brain and body tumors. These compounds combine the advantageous properties of 1-amino-cycloalkyl-1-carboxylic acids, namely, their rapid uptake and prolonged retention in tumors with the properties of halogen substituents, including certain useful halogen isotopes including fluorine-18, iodine-123, iodine-125, iodine-131, bromine-75, bromine-76, bromine-77 and bromine-82. In one aspect, the invention features amino acid compounds that have a high specificity for target sites when administered to a subject in vivo. Preferred amino acid compounds show a target to non-target ratio of at least 5:1, are stable in vivo and substantially localized to target within 1 hour after administration. An especially preferred amino acid compound is ›.sup.18 F!-1-amino-3-fluorocyclobutane-1-carboxylic acid (FACBC). In another aspect, the invention features pharmaceutical compositions comprised of an .alpha.-amino acid moiety attached to either a four, five, or a six member carbon-chain ring. In addition, the invention features analogs of .alpha.-aminoisobutyric acid.

  19. Amino acid analogs for tumor imaging

    DOEpatents

    Goodman, M.M.; Shoup, T.

    1998-09-15

    The invention provides novel amino acid compounds of use in detecting and evaluating brain and body tumors. These compounds combine the advantageous properties of 1-amino-cycloalkyl-1-carboxylic acids, namely, their rapid uptake and prolonged retention in tumors with the properties of halogen substituents, including certain useful halogen isotopes including fluorine-18, iodine-123, iodine-125, iodine-131, bromine-75, bromine-76, bromine-77 and bromine-82. In one aspect, the invention features amino acid compounds that have a high specificity for target sites when administered to a subject in vivo. Preferred amino acid compounds show a target to non-target ratio of at least 5:1, are stable in vivo and substantially localized to target within 1 hour after administration. An especially preferred amino acid compound is [{sup 18}F]-1-amino-3-fluorocyclobutane-1-carboxylic acid (FACBC). In another aspect, the invention features pharmaceutical compositions comprised of an {alpha}-amino acid moiety attached to either a four, five, or a six member carbon-chain ring. In addition, the invention features analogs of {alpha}-aminoisobutyric acid.

  20. Amino acid analogs for tumor imaging

    DOEpatents

    Goodman, M.M.; Shoup, T.

    1998-10-06

    The invention provides novel amino acid compounds of use in detecting and evaluating brain and body tumors. These compounds combine the advantageous properties of 1-amino-cycloalkyl-1-carboxylic acids, namely, their rapid uptake and prolonged retention in tumors with the properties of halogen substituents, including certain useful halogen isotopes including fluorine-18, iodine-123, iodine-125, iodine-131, bromine-75, bromine-76, bromine-77 and bromine-82. In one aspect, the invention features amino acid compounds that have a high specificity for target sites when administered to a subject in vivo. Preferred amino acid compounds show a target to non-target ratio of at least 5:1, are stable in vivo and substantially localized to target within 1 hour after administration. An especially preferred amino acid compound is [{sup 18}F]-1-amino-3-fluorocyclobutane-1-carboxylic acid (FACBC). In another aspect, the invention features pharmaceutical compositions comprised of an {alpha}-amino acid moiety attached to either a four, five, or a six member carbon-chain ring. In addition, the invention features analogs of {alpha}-aminoisobutyric acid.

  1. God attachment, mother attachment, and father attachment in early and middle adolescence.

    PubMed

    Sim, Tick Ngee; Yow, Amanda Shixian

    2011-06-01

    The present study examined the interplay of attachment to God, attachment to mother, and attachment to father with respect to adjustment (hope, self-esteem, depression) for 130 early and 106 middle adolescents in Singapore. Results showed that the parental attachments were generally linked (in expected directions) to adjustment. God attachment, however, had unique results. At the bivariate level, God attachment was only linked to early adolescents' self-esteem. When considered together with parental attachments (including interactions), God attachment did not emerge as the key moderator in attachment interactions and yielded some unexpected results (e.g., being positively linked to depression). These results are discussed viz-a-viz the secure base and safe haven functions that God and parental attachments may play during adolescence.

  2. Studies on the Protein Moiety of Endotoxin from Gram-Negative Bacteria: Characterization of the Protein Moiety Isolated by Phenol Treatment of Endotoxin from S. marcescens 08 and E. coli O 141:K85(B)

    DTIC Science & Technology

    E . coli 0 141:k85 (B) by aqueous phenol treatment were characterized by the determination of hydrodynamic properties, electrophoretic behavior, immunochemical specificity and chemical analysis. The chemical composition of both proteins revealed the presence of lipid A constituents such as glucosamine, phosphorus and fatty acids; the B-hydroxy myristic acid regarded as the characteristic marker for lipid A was present in all protein preparations. Evidence presented in this paper indicates that a portion of lipid A is firmly bound to the protein moieties. Therefore,

  3. Revealing the role of catechol moieties in the interactions between peptides and inorganic surfaces.

    PubMed

    Das, Priyadip; Reches, Meital

    2016-08-18

    Catechol (1,2-dihydroxy benzene) moieties are being widely used today in new adhesive technologies. Understanding their mechanism of action is therefore of high importance for developing their applications in materials science. This paper describes a single-molecule study of the interactions between catechol-related amino acid residues and a well-defined titanium dioxide (TiO2) surface. It is the first quantified measurement of the adhesion of these residues with a well-defined TiO2 surface. Single-molecule force spectroscopy measurements with AFM determined the role of different substitutions of the catechol moiety on the aromatic ring in the adhesion to the surface. These results shed light on the nature of interactions between these residues and inorganic metal oxide surfaces. This information is important for the design and fabrication of catechol-based materials such as hydrogels, coatings, and composites. Specifically, the interaction with TiO2 is important for the development of solar cells.

  4. Immobilization of imidazole moieties in polymer electrolyte composite membrane for elevated temperature fuel cells

    NASA Astrophysics Data System (ADS)

    Li, Ke; Zhou, Bei; Ye, Gongbo; Pan, Mu; Zhang, Haining

    2015-12-01

    Development of membrane electrolyte with reasonable proton conductivity at elevated temperature without external humidification is essential for practical applications of elevated temperature proton exchange membrane fuel cells. Herein, a novel polymer electrolyte composite membrane using imidazole as anhydrous proton carriers for elevated temperature fuel cells is investigated. The imidazole moieties are immobilized inside the Nafion/poly(tetrafluoroethylene) (PTFE) composite membrane through in situ formation of imidazole functionalized silica nanoparticles in Nafion dispersion. The thus-formed membrane exhibits strong Coulombic interaction between negatively charged sulfonic acid groups of Nafion and protonated imidazole moieties, leading to an anhydrous proton conductivity of 0.018 S cm-1 at 180 °C. With the introduction of PTFE matrix, the mechanical strength of the membrane is greatly improved. The peak power density of a single cell assembled from the hybrid membrane is observed to be 130 mW cm-2 under 350 mA cm-2 at 110 °C without external humidification and it remains stable for 20 h continuous operation. The obtained results demonstrate that the developed composite membranes could be utilized as promising membrane electrolytes for elevated temperature fuel cells.

  5. Resolution of diacylglycerol moieties of natural glycerophospholipids by gas-liquid chromatography on polar capillary columns.

    PubMed

    Myher, J J; Kuksis, A

    1982-06-01

    A rapid and practical method has been developed for the gas-liquid chromatographic determination of the sn-1,2-diacylglycerol moieties of natural glycerophospholipids using polar wall-coated open tubular columns. The method gives complete resolution and quantitative estimates for all species according to molecular weight and degree of unsaturation, including stearoyl docosahexaenoylglycerol and related polyunsaturates. For this purpose the sn-1,2-diacylglycerols are obtained from the glycerophospholipids by hydrolysis with phospholipase C and are converted into the trimethylsilyl or tertiary-butyldimethylsilyl ethers. The silyl ethers are separated by gas-liquid chromatography on the capillary glass columns coated with a polar cyanopropylsiloxane polymer, in the temperature range 175-250 degrees C, using hydrogen as the carrier gas. Practical applications of the method are illustrated by analyses of the sn-1,2-diacylglycerol moieties of the phosphatidylcholines of soybean phosphatides, egg yolk, and rat liver. The method of analysis is applicable to other classes of glycerophospholipids and the total time requirements for the analysis of any one phospholipid class are comparable to those for a fatty acid analysis.

  6. Turbine nozzle attachment system

    DOEpatents

    Norton, P.F.; Shaffer, J.E.

    1995-10-24

    A nozzle guide vane assembly having a preestablished rate of thermal expansion is positioned in a gas turbine engine and is attached to conventional metallic components. The nozzle guide vane assembly includes a pair of legs extending radially outwardly from an outer shroud and a pair of mounting legs extending radially inwardly from an inner shroud. Each of the pair of legs and mounting legs have a pair of holes therein. A plurality of members attached to the gas turbine engine have a plurality of bores therein which axially align with corresponding ones of the pair of holes in the legs. A plurality of pins are positioned within the corresponding holes and bores radially positioning the nozzle guide vane assembly about a central axis of the gas turbine engine. 3 figs.

  7. Turbine nozzle attachment system

    DOEpatents

    Norton, Paul F.; Shaffer, James E.

    1995-01-01

    A nozzle guide vane assembly having a preestablished rate of thermal expansion is positioned in a gas turbine engine and being attached to conventional metallic components. The nozzle guide vane assembly includes a pair of legs extending radially outwardly from an outer shroud and a pair of mounting legs extending radially inwardly from an inner shroud. Each of the pair of legs and mounting legs have a pair of holes therein. A plurality of members attached to the gas turbine engine have a plurality of bores therein which axially align with corresponding ones of the pair of holes in the legs. A plurality of pins are positioned within the corresponding holes and bores radially positioning the nozzle guide vane assembly about a central axis of the gas turbine engine.

  8. Fluorescence lifetime attachment LIFA

    NASA Astrophysics Data System (ADS)

    van der Oord, Cornelius J. R.; Stoop, Karel W. J.; van Geest, Lambertus K.

    2001-05-01

    We present the Lambert Instruments Fluorescence Lifetime Attachment LIFA. LIFA enables easy to use and affordable microscopy and macroscopic FLIM. The system implements the homodyne detection scheme for measuring the fluorescence lifetime in each pixel of the image. The microscopy system features an ultra bright LED illuminator, the LI-(mu) Cam intensified CCD camera a high frequency signal generator. The illuminator replaces the excitation light source of a standard fluorescence microscopy, while the LI-(mu) CAM intensified CCD camera is attached to the photo-port. Both the illuminator and the intensifier are modulated at a frequency up to 100 MHz at a series of phase differences. The lifetime image is calculated from the series of images on a personal computer.

  9. Examination of adipose depot-specific PPAR moieties

    SciTech Connect

    Dodson, M.V.; Vierck, J.L.; Hausman, G.J.; Guan, L.L.; Fernyhough, M.E.; Poulos, S.P.; Mir, P.S.; Jiang, Z.

    2010-04-02

    Molecular mechanisms of peroxisome proliferator activated receptors (PPARs) are being defined rapidly, as illustrated by the volume of papers published. Much of the research is directed towards a clinical end-point/application; however, the non-homogeneous nature of adipose depots in laboratory animals is spurring similar research in domestic meat animals (such as beef cattle). Moreover, the size of adipose depots in meat animals remains an attractive feature for using them to obtain cells for PPAR research. Examination of meat-animal depot-specific PPAR moieties may provide novel information about adipocyte regulation that might be extrapolated to all animals.

  10. Enumerating secondary structures and structural moieties for circular RNAs.

    PubMed

    Cuesta, Jose A; Manrubia, Susanna

    2017-04-21

    A quantitative characterization of the relationship between molecular sequence and structure is essential to improve our understanding of how function emerges. This particular genotype-phenotype map has been often studied in the context of RNA sequences, with the folded configurations standing as a proxy for the phenotype. Here, we count the secondary structures of circular RNAs of length n and calculate the asymptotic distributions of different structural moieties, such as stems or hairpin loops, by means of symbolic combinatorics. Circular RNAs differ in essential ways from their linear counterparts. From the mathematical viewpoint, the enumeration of the corresponding secondary structures demands the use of combinatorial techniques additional to those used for linear RNAs. The asymptotic number of secondary structures for circular RNAs grows as a(n)n(-5/2), with a depending on particular constraints applied to the secondary structure. As it occurs with linear RNA, the abundance of any structural moiety is normally distributed in the limit n→∞, with a mean and a variance that increase linearly with n.

  11. Oxygen permeability of hydrogel contact lenses with organosilicon moieties.

    PubMed

    Compañ, V; Andrio, A; López-Alemany, A; Riande, E; Refojo, M F

    2002-07-01

    Oxygen transport through two extended wear (day and night) hydrogel contact lenses that contain organosilicon moieties (balafilcon A and lotrafilcon A) was studied in the hydrate (hydrogel) and dry (xerogel) states. The water uptake increased the oxygen permeability [(Dk)app] and transmissibility [Dk/L(av)] coefficients of the dry materials by about 70%. The (Dk)app for the hydrated lenses was determined following the so-called stack procedure. The values obtained were 107 +/- 4 barrer for balafilcon A and 141 +/- 5 barrer for lotrafilcon A, about 5-10 times larger than those previously reported for conventional (without organosilicon moieties) extended wear hydrogels contact lenses. The Dk/L(av) for -3.00 diopter lenses (harmonic average thickness, L(av) = 75 +/- 2 microm for lotrafilcon, and 85 +/- 2 microm for balafilcon) was 123 +/- 6 barrer/cm for balafilcon A and 183 +/- 8 barrer/cm for lotralicon A. The minimum oxygen transmissibility 87 barrer/cm stipulated by Holden and Mertz to avoid corneal edema with extended wear contact can be easily achieved with lotrafilcon and balafilcon lenses of diverse dioptric powers if the central and peripheral thickness of the lenses are kept below the critical level of oxygen transmissibility.

  12. Attachment and Relationships: Beyond Parenting.

    ERIC Educational Resources Information Center

    Honig, Alice Sterling

    Using a question-answer format, this paper examines the concept of attachment and its importance for parents and caregivers of young children. Twenty topics are addressed through an examination of relevant theory, research findings, and clinical evidence: (1) a "who's who" list of researchers on attachment; (2) definition of attachment;…

  13. Adopting Children with Attachment Problems.

    ERIC Educational Resources Information Center

    Hughes, Daniel A.

    1999-01-01

    Notes that attachment behavior in infants is a facet of normal child development, and that children with attachment problems require special attention during and after the adoption process. Presents actions needed to increase the probability that such children can be successfully adopted, detailed attachment patterns, and parenting strategies and…

  14. Attachment Theory: Retrospect and Prospect.

    ERIC Educational Resources Information Center

    Bretherton, Inge

    1985-01-01

    Provides overview of attachment theory as parented by John Bowlby in "Attachment and Loss". Uses two major concepts from this work to interpret refinements and elaborations of attachment theory attibuted to Mary Ainsworth. Considers how recent insights into development of socioemotional understanding and development of event…

  15. Attachment: Theoretical Development and Critique

    ERIC Educational Resources Information Center

    Slater, Ruth

    2007-01-01

    Zeanah argues that ethological attachment theory, as outlined by John Bowlby, has provided one of the most important frameworks for understanding crucial risk and protective factors in social and emotional development. However, although attachment theory and the notion of attachment disorders have influenced such initiatives, many psychologists,…

  16. Attachment as Regulation: A Commentary.

    ERIC Educational Resources Information Center

    Pipp, Sandra; Harmon, Robert J.

    1987-01-01

    Discusses ways in which Myron Hofer's work (1987), which draws on studies of rodents and primates, alters the traditional perspective on human attachment. Emphasizes the importance of the component of attachment that does not develop in explaining attachment in the first six months of life. (PCB)

  17. Identification and analytical properties of new synthetic cannabimimetics bearing 2,2,3,3-tetramethylcyclopropanecarbonyl moiety.

    PubMed

    Shevyrin, Vadim; Melkozerov, Vladimir; Nevero, Alexander; Eltsov, Oleg; Morzherin, Yuri; Shafran, Yuri

    2013-03-10

    By means of gas chromatography with mass spectrometry detector (GC-MS), liquid chromatography-mass spectrometry (LC-MS) and nuclear magnetic resonance spectroscopy (NMR), structure of a series from a novel class of synthetic cannabimimetics bearing 2,2,3,3-tetramethylcyclopropanecarbonyl moiety was established. It was found that this fragment could undergo thermal ring-opening into isomeric structures. The title compounds under action of hydrochloric acid can transform into new compounds which structure is discussed in the paper. The compounds identified could be referred to a new class of 'designer drugs' and are in illegal turnover in Russia and Belarus since the summer of 2011. Analytical data obtained in the paper will make possible reliable identification of such new 'designer drugs' during forensic examination.

  18. Carbohydrate Moieties and Cytoenzymatic Characterization of Hemocytes in Whiteleg Shrimp Litopenaeus vannamei

    PubMed Central

    Velázquez, Edwin; Rodríguez-Jaramillo, Carmen; Ascencio, Felipe

    2016-01-01

    Hemocytes represent one of the most important defense mechanisms against foreign material in Crustacea and are also involved in a variety of other physiological responses. Fluorescent lectin-binding assays and cytochemical reactions were used to identify specificity and distribution of carbohydrate moieties and presence of several hydrolytic enzymes, in hemocytes of whiteleg shrimp Litopenaeus vannamei. Two general classes of circulating hemocytes (granular and agranular) exist in L. vannamei, which express carbohydrates residues for FITC-conjugated lectins WGA, LEA, and PNA; UEA and Con-A were not observed. Enzymatic studies indicated that acid phosphatase, nonspecific esterase, and specific esterases were present; alkaline phosphatase was not observed. The enzymes and carbohydrates are useful tools in hemocyte classification and cellular defense mechanism studies. PMID:27833641

  19. Structural design of new alicyclic acrylate polymers with androstane moiety for 193-nm resist

    NASA Astrophysics Data System (ADS)

    Aoai, Toshiaki; Sato, Kenichiro; Kodama, Kunihiko; Kawabe, Yasumasa; Nakao, Hajime; Yagihara, Morio

    1999-06-01

    Synthesis of new alicyclic (meth)acrylate polymers containing androstane moieties, especially cholic acid derivatives, and their characteristics were investigated for 193nm single layer resists. Among the derivatives, a work of adhesion, Ohnishi and ring parameters were used as measures for the adhesion and the dry-etching resistance in this study. In the synthesis of the polymers, the use of 3- (beta) -methacryloyoxy-deoxycholic acid, which is the inverse configuration against the original 3-(alpha) -structure, was effective as a monomer, because the steric hindrance at 3- (alpha) -position degraded its polymerization ability. The polymers partially protected by acid labile groups showed a satisfactory adhesion, which was probably due to the hydrophilic hydroxyl group at the 12-position and the carboxyl group linked at the 17-position, and a good dry- etching resistance. On the lithographic imaging with these polymers, the reduction of the side reaction on the acid decomposition and also the control of the flexibility on the polymers largely affected their performance. THe adjustment of the Tg values of the polymers by the co-polymerization and the change of the polymer backbone from the methacrylate to acrylate structure performed well on imaging under 193nm exposure.

  20. Requirements for Carnitine Shuttle-Mediated Translocation of Mitochondrial Acetyl Moieties to the Yeast Cytosol

    PubMed Central

    van Rossum, Harmen M.; Kozak, Barbara U.; Niemeijer, Matthijs S.; Dykstra, James C.; Luttik, Marijke A. H.; van Maris, Antonius J. A.

    2016-01-01

    ABSTRACT In many eukaryotes, the carnitine shuttle plays a key role in intracellular transport of acyl moieties. Fatty acid-grown Saccharomyces cerevisiae cells employ this shuttle to translocate acetyl units into their mitochondria. Mechanistically, the carnitine shuttle should be reversible, but previous studies indicate that carnitine shuttle-mediated export of mitochondrial acetyl units to the yeast cytosol does not occur in vivo. This apparent unidirectionality was investigated by constitutively expressing genes encoding carnitine shuttle-related proteins in an engineered S. cerevisiae strain, in which cytosolic acetyl coenzyme A (acetyl-CoA) synthesis could be switched off by omitting lipoic acid from growth media. Laboratory evolution of this strain yielded mutants whose growth on glucose, in the absence of lipoic acid, was l-carnitine dependent, indicating that in vivo export of mitochondrial acetyl units to the cytosol occurred via the carnitine shuttle. The mitochondrial pyruvate dehydrogenase complex was identified as the predominant source of acetyl-CoA in the evolved strains. Whole-genome sequencing revealed mutations in genes involved in mitochondrial fatty acid synthesis (MCT1), nuclear-mitochondrial communication (RTG2), and encoding a carnitine acetyltransferase (YAT2). Introduction of these mutations into the nonevolved parental strain enabled l-carnitine-dependent growth on glucose. This study indicates intramitochondrial acetyl-CoA concentration and constitutive expression of carnitine shuttle genes as key factors in enabling in vivo export of mitochondrial acetyl units via the carnitine shuttle. PMID:27143389

  1. Synthesis and Characterization of Thermally Stable Photocurable Polymer with Cyclohexane Moiety.

    PubMed

    Kim, Dong Mm; Yu, Seong Hun; Lee, Jun Young

    2016-03-01

    Photocurable polymers with high transparency and thermal stability were synthesized by reaction between a commercial epoxy resin (NC9110) containing cyclohexane moiety and various kinds of cinnamic acids such as trans-cinnamic acid (CA), 3-hydroxy-trans-cinnamic acid (HCA) and 4-methoxy-trans-cinnamic acid (MCA). The photocurable polymers were synthesized with equal equivalent weight ratio of epoxy and cinnamate group. The chemical structures of the synthesized polymers were confirmed by 1H-NMR and FT-IR spectroscopies. Optical transmittance and thermal stability of the photocured polymers were investigated using UV-Visible spectroscopy and thermogravimetric analysis (TGA), respectively. It was confirmed that the polymers could form thin films with very smooth surface and could be efficiently cured by UV irradiation. It was also found that the polymer after curing showed a good thermal stability and optical transmittance. There was no significant transmittance change after heat treatment at 250 degrees C for 1 h and showed no noticeable weight loss up to 360 degrees C.

  2. Report of the APSAC task force on attachment therapy, reactive attachment disorder, and attachment problems.

    PubMed

    Chaffin, Mark; Hanson, Rochelle; Saunders, Benjamin E; Nichols, Todd; Barnett, Douglas; Zeanah, Charles; Berliner, Lucy; Egeland, Byron; Newman, Elana; Lyon, Tom; LeTourneau, Elizabeth; Miller-Perrin, Cindy

    2006-02-01

    Although the term attachment disorder is ambiguous, attachment therapies are increasingly used with children who are maltreated, particularly those in foster care or adoptive homes. Some children described as having attachment disorders show extreme disturbances. The needs of these children and their caretakers are real. How to meet their needs is less clear. A number of attachment-based treatment and parenting approaches purport to help children described as attachment disordered. Attachment therapy is a young and diverse field, and the benefits and risks of many treatments remain scientifically undetermined. Controversies have arisen about potentially harmful attachment therapy techniques used by a subset of attachment therapists. In this report, the Task Force reviews the controversy and makes recommendations for assessment, treatment, and practices. The report reflects American Professional Society on the Abuse of Children's (APSAC) position and also was endorsed by the American Psychological Association's Division 37 and the Division 37 Section on Child Maltreatment.

  3. Synthesis and biological activity of thiazolyl-acetic acid derivatives as possible antimicrobial agents.

    PubMed

    Shirai, Akihiro; Fumoto, Yasuko; Shouno, Tomoaki; Maseda, Hideaki; Omasa, Takeshi

    2013-01-01

    5a-h, a series of (5-substituted-2-methyl-1,3-thiazole-4-yl) acetic acids as heterocyclic acetic acid derivatives, was designed and synthesized from ethyl acetoacetate. The synthesized compounds were screened for their antimicrobial activities against bacterial and fungal strains, and their characteristics were investigated by assays under various temperature and pH conditions. Cytotoxicity was evaluated with the use of sheep erythrocytes and human neonate dermal fibroblasts. Similarly, agents such as lauric acid 6 and parabens 7a-b, which are used as preservative agents for commercial cosmetics and detergents, were assayed for comparison. Although the structure of 5a is simple, comprising a thiazole attached with an octyl group and acetic acid moiety, the compound showed stronger and broader antibacterial and antifungal activities among the 5 series against the tested microbes other than gram-negative bacteria. Interestingly, 5a overcame the weak antifungal activity of parabens 7a-b. Also, the cytotoxicity of 5a was less than that of parabens 7a-b, especially to human dermal fibroblasts. These results suggest that thiazolyl-acetic acid 5a is a potentially effective biocide, and that it could be used as a preservative agent in commercially sold cosmetics and detergents, facilitated by the hydrophilic and charge properties of its carboxylic acid moiety.

  4. Ceramic blade attachment system

    DOEpatents

    Frey, deceased, Gary A.; Jimenez, Oscar D.

    1996-01-01

    A turbine blade having a preestablished rate of thermal expansion is attached to a turbine flange having a preestablished rate of thermal expansion being greater than the preestablished rate of thermal expansion of the turbine blade. The turbine flange includes a first upstanding flange and a second upstanding flange having a groove formed therebetween. The turbine flange further includes a recess. Each of the first and second upstanding flanges have a plurality of bores therein. A turbine blade has a first member and a second member positioned in one of the groove and the recess. Each of the first member and the second member have a plurality of bores therein. And, a pin is positioned in respective ones of the plurality of bores in the first and second upstanding members and the first and second members and attach the blade to the turbine flange. The pin has a preestablished rate of thermal expansion being substantially equal to the rate of thermal expansion of the blade.

  5. Ceramic blade attachment system

    DOEpatents

    Frey, G.A.; Jimenez, O.D.

    1996-12-03

    A turbine blade having a preestablished rate of thermal expansion is attached to a turbine flange having a preestablished rate of thermal expansion being greater than the preestablished rate of thermal expansion of the turbine blade. The turbine flange includes a first upstanding flange and a second upstanding flange having a groove formed between them. The turbine flange further includes a recess. Each of the first and second upstanding flanges have a plurality of bores therein. A turbine blade has a first member and a second member positioned in one of the groove and the recess. Each of the first member and the second member have a plurality of bores therein. A pin is positioned in respective ones of the plurality of bores in the first and second upstanding members and the first and second members and attach the blade to the turbine flange. The pin has a preestablished rate of thermal expansion being substantially equal to the rate of thermal expansion of the blade. 4 figs.

  6. Neighborhood Quality and Attachment

    PubMed Central

    Poortinga, Wouter; Calve, Tatiana; Jones, Nikki; Lannon, Simon; Rees, Tabitha; Rodgers, Sarah E.; Lyons, Ronan A.; Johnson, Rhodri

    2016-01-01

    Various studies have shown that neighborhood quality is linked to neighborhood attachment and satisfaction. However, most have relied upon residents’ own perceptions rather than independent observations of the neighborhood environment. This study examines the reliability and validity of the revised Residential Environment Assessment Tool (REAT 2.0), an audit instrument covering both public and private spaces of the neighborhood environment. The research shows that REAT 2.0 is a reliable, easy-to-use instrument and that most underlying constructs can be validated against residents’ own neighborhood perceptions. The convergent validity of the instrument, which was tested against digital map data, can be improved for a number of miscellaneous urban form items. The research further found that neighborhood attachment was significantly associated with the overall REAT 2.0 score. This association can mainly be attributed to the property-level neighborhood quality and natural elements components. The research demonstrates the importance of private spaces in the outlook of the neighborhood environment. PMID:28260806

  7. Nanostructured carbon materials decorated with organophosphorus moieties: synthesis and application

    PubMed Central

    Biagiotti, Giacomo; Langè, Vittoria; Ligi, Cristina; Caporali, Stefano; Muniz-Miranda, Maurizio; Flis, Anna; Pietrusiewicz, K Michał; Ghini, Giacomo; Brandi, Alberto

    2017-01-01

    A new synthetic approach for the production of carbon nanomaterials (CNM) decorated with organophosphorus moieties is presented. Three different triphenylphosphine oxide (TPPO) derivatives were used to decorate oxidized multiwalled carbon nanotubes (ox-MWCNTs) and graphene platelets (GPs). The TPPOs chosen bear functional groups able to react with the CNMs by Tour reaction (an amino group), nitrene cycloaddition (an azido group) or CuAAC reaction (one terminal C–C triple bond). All the adducts were characterized by FTIR, Raman spectroscopy, TEM, XPS, elemental analysis and ICP-AES. The cycloaddition of nitrene provided the higher loading on ox-MWCNTs and GPs as well, while the Tour approach gave best results with nanotubes (CNTs). Finally, we investigated the possibility to reduce the TPPO functionalized CNMs to the corresponding phosphine derivatives and applied one of the materials produced as heterogeneous organocatalyst in a Staudinger ligation reaction. PMID:28326239

  8. Photoisomerization of azobenzene moiety in crosslinking polymer materials

    NASA Astrophysics Data System (ADS)

    Wang, Hui; Chen, Wei-Qiang; Jin, Feng; Dong, Xian-Zi; Zhao, Zhen-Sheng; Duan, Xuan-Ming

    2012-10-01

    In this study, a series of acryloyloxy-substituted azobenzene derivatives, 3-(tert-butyl)-4,4'-bisacryoloxy-azobenzene (tBu-Azo-AO), 3-(tert-butyl)-4,4'-bis[3-(acryoloxy)propoxy]-azobenzene (tBu-Azo-AO3) and 3-(tert-butyl)-4,4'-bis[6-(acryoloxy)hexyloxy]-azobenzene (tBu-Azo-AO6) were synthesized and employed as monomers to prepare polymer films by copolymerizing dipentaerythritol hexaacrylate (DPE-6A) and methyl methacrylate (MMA), respectively. When exposed to a nanosecond laser beam at the wavelength of 355 nm, ultraviolet-visible (UV-Vis) absorption spectra of the resultant polymer films with different irradiation time were monitored. On the basis of the absorbance of the π-π* electronic transition, the kinetics of trans-to-cis photoisomerization of three kinds of azobenzene moieties were demonstrated and found to be influenced by both the pump energy and azobenzene concentration.

  9. Electron attachment to indole and related molecules

    SciTech Connect

    Modelli, Alberto; Jones, Derek; Pshenichnyuk, Stanislav A.

    2013-11-14

    Gas-phase formation of temporary negative ion states via resonance attachment of low-energy (0–6 eV) electrons into vacant molecular orbitals of indoline (I), indene (II), indole (III), 2-methylen-1,3,3-trimethylindoline (IV), and 2,3,3-trimethyl-indolenine (V) was investigated for the first time by electron transmission spectroscopy (ETS). The description of their empty-level structures was supported by density functional theory and Hartree-Fock calculations, using empirically calibrated linear equations to scale the calculated virtual orbital energies. Dissociative electron attachment spectroscopy (DEAS) was used to measure the fragment anion yields generated through dissociative decay channels of the parent molecular anions of compounds I-V, detected with a mass filter as a function of the incident electron energy in the 0–14 eV energy range. The vertical and adiabatic electron affinities were evaluated at the B3LYP/6-31+G(d) level as the anion/neutral total energy difference. The same theoretical method is also used for evaluation of the thermodynamic energy thresholds for production of the negative fragments observed in the DEA spectra. The loss of a hydrogen atom from the parent molecular anion ([M-H]{sup −}) provides the most intense signal in compounds I-IV. The gas-phase DEAS data can provide support for biochemical reaction mechanisms in vivo involving initial hydrogen abstraction from the nitrogen atom of the indole moiety, present in a variety of biologically important molecules.

  10. Ceramic blade attachment system

    DOEpatents

    Shaffer, James E.

    1995-01-01

    A turbine blade having a preestablished rate of thermal expansion is attached to a turbine disc having a preestablished rate of thermal expansion being greater than the preestablished rate of thermal expansion of the turbine blade and forms a turbine assembly. The turbine blade has a root portion defining a pair of sides having a pair of grooves therein. The turbine assembly includes a pair of flanges between which the turbine blades are positioned. Each of the pair of flanges has a plurality of grooves defined therein. The grooves within the pair of flanges are aligned with the grooves in the blades and have a space formed therebetween. A plurality of spherical balls are positioned within the space. The plurality of spherical balls has a preestablished rate of thermal expansion being equal to the preestablished rate of thermal expansion of the turbine blade.

  11. Ceramic blade attachment system

    DOEpatents

    Shaffer, J.E.

    1995-01-10

    A turbine blade having a preestablished rate of thermal expansion is attached to a turbine wheel having a preestablished rate of thermal expansion being greater than the preestablished rate of thermal expansion of the turbine blade. The turbine blade has a root portion having a first groove and a second groove therein. The turbine wheel includes a plurality of openings in which the turbine blade is positioned. Each of the openings has a first groove and a second groove therein. The space or void formed between the first grooves and the second grooves has a plurality of spherical balls positioned therein. The plurality of spherical balls has a preestablished rate of thermal expansion being equal to the preestablished rate of thermal expansion of the turbine blade. 4 figures.

  12. Ceramic blade attachment system

    DOEpatents

    Shaffer, J.E.

    1995-07-11

    A turbine blade having a preestablished rate of thermal expansion is attached to a turbine disc having a preestablished rate of thermal expansion being greater than the preestablished rate of thermal expansion of the turbine blade and forms a turbine assembly. The turbine blade has a root portion defining a pair of sides having a pair of grooves therein. The turbine assembly includes a pair of flanges between which the turbine blades are positioned. Each of the pair of flanges has a plurality of grooves defined therein. The grooves within the pair of flanges are aligned with the grooves in the blades and have a space formed therebetween. A plurality of spherical balls are positioned within the space. The plurality of spherical balls has a preestablished rate of thermal expansion being equal to the preestablished rate of thermal expansion of the turbine blade. 4 figs.

  13. Ceramic blade attachment system

    DOEpatents

    Shaffer, James E.

    1995-01-01

    A turbine blade having a preestablished rate of thermal expansion is attached to a turbine wheel having a preestablished rate of thermal expansion being greater than the preestablished rate of thermal expansion of the turbine blade. The turbine blade has a root portion having a first groove and a second groove therein. The turbine wheel includes a plurality of openings in which the turbine blade is positioned. Each of the openings has a first groove and a second groove therein. The space or void formed between the first grooves and the second grooves has a plurality of spherical balls positioned therein. The plurality of spherical balls has a preestablished rate of thermal expansion being equal to the preestablished rate of thermal expansion of the turbine blade.

  14. Perfluorinated Moieties Increase the Interaction of Amphiphilic Block Copolymers with Lipid Monolayers.

    PubMed

    Schwieger, Christian; Blaffert, Jacob; Li, Zheng; Kressler, Jörg; Blume, Alfred

    2016-08-16

    The interaction of amphiphilic and triphilic block copolymers with lipid monolayers has been studied. Amphiphilic triblock copolymer PGMA20-PPO34-PGMA20 (GP) is composed of a hydrophobic poly(propylene oxide) (PPO) middle block that is flanked by two hydrophilic poly(glycerol monomethacrylate) (PGMA) side blocks. The attachment of a perfluoro-n-nonyl residue (F9) to either end of GP yields a triphilic polymer with the sequence F9-PGMA20-PPO34-PGMA20-F9 (F-GP). The F9 chains are fluorophilic, i.e., they have a tendency to demix in hydrophilic as well as in lipophilic environments. We investigated (i) the adsorption of both polymers to differently composed lipid monolayers and (ii) the compression behavior of mixed polymer/lipid monolayers. The lipid monolayers are composed of phospholipids with PC or PE headgroups and acyl chains of different length and saturation. Both polymers interact with lipid monolayers by inserting their hydrophobic moieties (PPO, F9). The interaction is markedly enhanced in the presence of F9 chains, which act as membrane anchors. GP inserts into lipid monolayers up to a surface pressure of 30 mN/m, whereas F-GP inserts into monolayers at up to 45 mN/m, suggesting that F-GP also inserts into lipid bilayer membranes. The adsorption of both polymers to lipid monolayers with short acyl chains is favored. Upon compression, a two-step squeeze-out of F-GP occurs, with PPO blocks being released into the aqueous subphase at 28 mN/m and the F9 chains being squeezed out at 48 mN/m. GP is squeezed out in one step at 28 mN/m because of the lack of F9 anchor groups. The liquid expanded (LE) to liquid condensed (LC) phase transition of DPPC and DMPE is maintained in the presence of the polymers, indicating that the polymers can be accommodated in LE- and LC-phase monolayers. These results show how fluorinated moieties can be included in the rational design of membrane-binding polymers.

  15. Complexes of technetium-99m with tetrapeptides containing one alanyl and three glycyl moieties.

    PubMed

    Vanbilloen, H P; De Roo, M J; Verbruggen, A M

    1996-01-01

    Recently, we have shown that tetrapeptides can be efficiently labelled with technetium-99m by direct labelling at alkaline pH. Tetrapeptides can be considered derivatives of mercaptoacetyltriglycine (MAG3) in which the mercaptoacetyl moiety is replaced by an amino acid residue. In view of the interesting biological properties of some C-methyl substituted derivatives of 99mTc-MAG3, we have now synthesised and evaluated the complexes of 99mTc with tetrapeptides containing three glycyl (G) moieties and one D- or L-alanyl (A) moiety. In mice, 99mTc-L-GAGG, 99mTc-D-GGAG and 99mTc-L-GGAG showed a rapid and high renal excretion, comparable to that of 99mTc-MAG3. Renal handling was somewhat reduced for isomers d and l of 99mTc-AGGG and 99mTc-D-GAGG and markedly inferior for 99mTc-L-GGGA and 99mTc-D-GGGA. In the baboon, 99mTc-L-AGGG, 99mTc-D-AGGG and 99mTc-L-GAGG showed a comparable or even higher 1-h plasma clearance than 99mTc-MAG3. 99mTc-D-GAGG, 99mTc-L-GGAG and 99mTc-D-GGAG were characterised by a lower plasma clearance and the clearance of 99mTc-L-GGGA and 99mTc-D-GGGA was remarkably low. The three 99mTc-labelled tetrapeptides with the highest plasma clearance in a baboon were compared with 99mTc-MAG3 in a human volunteer. 99mTc-L-AGGG and 99mTc-L-GAGG had a roughly similar plasma clearance as 99mTc-MAG3. The clearance of 99mTc-D-AGGG was significantly lower and liver uptake was clearly visible with this compound. Left kidney renograms of 99mTc-L-AGGG and 99mTc-D-AGGG indicated moderate kidney accumulation. On the other hand, the renogram obtained after injection of 99mTc-L-GAGG had an excellent shape and the maximum kidney concentration was slightly higher than for 99mTc-MAG3. These results show the importance of the position of the methyl substituent on the 99mTc-tetrapeptide with respect to its biological behaviour.

  16. Sentence-Level Attachment Prediction

    NASA Astrophysics Data System (ADS)

    Albakour, M.-Dyaa; Kruschwitz, Udo; Lucas, Simon

    Attachment prediction is the task of automatically identifying email messages that should contain an attachment. This can be useful to tackle the problem of sending out emails but forgetting to include the relevant attachment (something that happens all too often). A common Information Retrieval (IR) approach in analyzing documents such as emails is to treat the entire document as a bag of words. Here we propose a finer-grained analysis to address the problem. We aim at identifying individual sentences within an email that refer to an attachment. If we detect any such sentence, we predict that the email should have an attachment. Using part of the Enron corpus for evaluation we find that our finer-grained approach outperforms previously reported document-level attachment prediction in similar evaluation settings.

  17. Elderly-animal postmortem attachment.

    PubMed

    Peretti, P O

    1990-01-01

    Attachment can be strong between people and their pets. The present study was conducted to determine: (1) specific variables associated with the final rite and disposition of the deceased pet, and (2) those criteria associated with emotional and social factors pertaining to elderly-animal postmortem attachment. Results suggested four most frequently stated variables of final rite and disposition, and eight emotional and social factors of elderly-animal postmortem attachment.

  18. An overview of frenal attachments

    PubMed Central

    Priyanka, M.; Sruthi, R.; Ramakrishnan, T.; Emmadi, Pamela; Ambalavanan, N.

    2013-01-01

    Frenal attachments are thin folds of mucous membrane with enclosed muscle fibers that attach the lips to the alveolar mucosa and underlying periosteum. Most often, during the oral examination of the patient the dentist gives very little importance to the frenum, for assessing its morpholology and attachment. However, it has been seen that an abnormal frenum can be an indicator of a syndrome. This paper highlights the different frenal attachments seen in association with various syndromic as well as non-syndromic conditions. PMID:23633765

  19. Noble polymeric surface conjugated with zwitterionic moieties and antibodies for the isolation of exosomes from human serum.

    PubMed

    Kim, Gahee; Yoo, Chang Eun; Kim, Myoungsoon; Kang, Hyun Ju; Park, Donghyun; Lee, Myoyong; Huh, Nam

    2012-10-17

    New zwitterionic polymer-coated immunoaffinity beads were developed to resist nonspecific protein adsorption from undiluted human serum for diagnostic applications of exosomes. A zwitterionic sulfobetaine monomer with an amine functional group was employed for simple surface chemistry and antifouling properties. An exosomal biomarker protein, epithelial cell adhesion molecule (EpCAM), was selected as a target molecule in this work. The beads were coated with polyacrylic acids (PAA) for increasing biorecognition sites, and protein G was then conjugated with carboxylic acid groups on the surfaces for controlling EpCAM antibody orientation. The remaining free carboxylic acid groups were modified with sulfobetaine moieties, and anti-EpCAM antibody was finally introduced. The amount of anti-EpCAM on the beads was increased by 40% when compared with PAA-uncoated beads. The surfaces of the beads exhibited near-net-zero charge, and nonspecific protein adsorption was effectively suppressed by sulfobetaine moieties. EpCAM was captured from undiluted human serum with almost the same degree of efficiency as from PBS buffer solution using the newly developed immunoaffinity beads.

  20. Identification of Conserved Moieties in Metabolic Networks by Graph Theoretical Analysis of Atom Transition Networks

    PubMed Central

    Haraldsdóttir, Hulda S.; Fleming, Ronan M. T.

    2016-01-01

    Conserved moieties are groups of atoms that remain intact in all reactions of a metabolic network. Identification of conserved moieties gives insight into the structure and function of metabolic networks and facilitates metabolic modelling. All moiety conservation relations can be represented as nonnegative integer vectors in the left null space of the stoichiometric matrix corresponding to a biochemical network. Algorithms exist to compute such vectors based only on reaction stoichiometry but their computational complexity has limited their application to relatively small metabolic networks. Moreover, the vectors returned by existing algorithms do not, in general, represent conservation of a specific moiety with a defined atomic structure. Here, we show that identification of conserved moieties requires data on reaction atom mappings in addition to stoichiometry. We present a novel method to identify conserved moieties in metabolic networks by graph theoretical analysis of their underlying atom transition networks. Our method returns the exact group of atoms belonging to each conserved moiety as well as the corresponding vector in the left null space of the stoichiometric matrix. It can be implemented as a pipeline of polynomial time algorithms. Our implementation completes in under five minutes on a metabolic network with more than 4,000 mass balanced reactions. The scalability of the method enables extension of existing applications for moiety conservation relations to genome-scale metabolic networks. We also give examples of new applications made possible by elucidating the atomic structure of conserved moieties. PMID:27870845

  1. Protein Attachment on Nanodiamonds.

    PubMed

    Lin, Chung-Lun; Lin, Cheng-Huang; Chang, Huan-Cheng; Su, Meng-Chih

    2015-07-16

    A recent advance in nanotechnology is the scale-up production of small and nonaggregated diamond nanoparticles suitable for biological applications. Using detonation nanodiamonds (NDs) with an average diameter of ∼4 nm as the adsorbents, we have studied the static attachment of three proteins (myoglobin, bovine serum albumin, and insulin) onto the nanoparticles by optical spectroscopy, mass spectrometry, and dynamic light scattering, and electrophoretic zeta potential measurements. Results show that the protein surface coverage is predominantly determined by the competition between protein-protein and protein-ND interactions, giving each protein a unique and characteristic structural configuration in its own complex. Specifically, both myoglobin and bovine serum albumin show a Langmuir-type adsorption behavior, forming 1:1 complexes at saturation, whereas insulin folds into a tightly bound multimer before adsorption. The markedly different adsorption patterns appear to be independent of the protein concentration and are closely related to the affinity of the individual proteins for the NDs. The present study provides a fundamental understanding for the use of NDs as a platform for nanomedical drug delivery.

  2. Dissociative Electron Attachment

    NASA Astrophysics Data System (ADS)

    Arreola, Esmeralda; Esmeralda Arreola Collaboration; Leigh Hargreaves Collaboration

    Since the pioneering work of Boudiaffa et al., it has been understood that electrons, even with energies near or below the ionization threshold, are capable of initiating strand-breaks in human DNA. This discovery raised important questions for cancer treatments, since sub-ionizing electrons are known to be the most copiously produced secondary product of radiation therapy. But even to date these factors are largely excluded from dosimetry calculations. This lack of inclusion is, at least in part, certainly due to the dearth of fundamental data describing low-energy electron interactions with nucleotide molecules that form the basis of DNA. Understanding of how such slow electrons are able to damage DNA remains incomplete, but the strongly peaked nature of Boudiaffa et al.'s data gives strong hints at resonantly driven collision processes. DNA damage is therefore most likely driven by ``dissociative electron attachment'' (DEA). DEA is a rather complicated process to model due to the coupling of electronic and nuclear degrees of freedom in the molecule. At the California State University Fullerton, we are currently commissioning a new spectrometer to study dissociation channels, reaction rates and orientation effects in DEA collisions between slow electrons and nucleotide molecules. At the meeting we will present design parameters and commissioning data for this new apparatus.

  3. Substratum interfacial energetic effects on the attachment of marine bacteria

    NASA Astrophysics Data System (ADS)

    Ista, Linnea Kathryn

    Biofilms represent an ancient, ubiquitous and influential form of life on earth. Biofilm formation is initiated by attachment of bacterial cells from an aqueous suspension onto a suitable attachment substratum. While in certain, well studied cases initial attachment and subsequent biofilm formation is mediated by specific ligand-receptor pairs on the bacteria and attachment substratum, in the open environment, including the ocean, it is assumed to be non-specific and mediated by processes similar to those that drive adsorption of colloids at the water-solid interface. Colloidal principles are studied to determine the molecular and physicochemical interactions involved in the attachment of the model marine bacterium, Cobetia marina to model self-assembled monolayer surfaces. In the simplest application of colloidal principles the wettability of attachment substrata, as measured by the advancing contact angle of water (theta AW) on the surface, is frequently used as an approximation for the surface tension. We demonstrate the applicability of this approach for attachment of C. marina and algal zoospores and extend it to the development of a means to control attachment and release of microorganisms by altering and tuning surface thetaAW. In many cases, however, thetaAW does not capture all the information necessary to model attachment of bacteria to attachment substrata; SAMs with similar thetaAW attach different number of bacteria. More advanced colloidal models of initial bacterial attachment have evolved over the last several decades, with the emergence of the model proposed by van Oss, Chaudhury and Good (VCG) as preeminent. The VCG model enables calculation of interfacial tensions by dividing these into two major interactions thought to be important at biointerfaces: apolar, Lifshitz-van der Waals and polar, Lewis acid-base (including hydrogen bonding) interactions. These interfacial tensions are combined to yield DeltaGadh, the free energy associated with

  4. Toxicology of Perfluoroalkyl Acids*

    EPA Science Inventory

    The perfluoroalkyl acids (PFAAs) are a family of organic chemicals consisting of a perfluorinated carbon backbone (4-12 in length) and an acidic functional moiety (carboxylate or sulfonate). These compounds are chemically stable, have excellent surface-tension reducing properties...

  5. Rational Design and Synthesis of New, High Efficiency, Multipotent Schiff Base-1,2,4-triazole Antioxidants Bearing Butylated Hydroxytoluene Moieties.

    PubMed

    Yehye, Wageeh A; Abdul Rahman, Noorsaadah; Saad, Omar; Ariffin, Azhar; Abd Hamid, Sharifah Bee; Alhadi, Abeer A; Kadir, Farkaad A; Yaeghoobi, Marzieh; Matlob, Abdulsalam A

    2016-06-28

    A new series of multipotent antioxidants (MPAOs), namely Schiff base-1,2,4-triazoles attached to the oxygen-derived free radical scavenging moiety butylated hydroxytoluene (BHT) were designed and subsequently synthesized. The structure-activity relationship (SAR) of the designed antioxidants was established alongside the prediction of activity spectra for substances (PASS). The antioxidant activities of the synthesized compounds 4-10 were tested by the DPPH bioassay. The synthesized compounds 4-10 inhibited stable DPPH free radicals at a level that is 10(-4) M more than the well-known standard antioxidant BHT. Compounds 8-10 with para-substituents were less active than compounds 4 and 5 with trimethoxy substituents compared to those with a second BHT moiety (compounds 6 and 7). With an IC50 of 46.13 ± 0.31 µM, compound 6 exhibited the most promising in vitro inhibition at 89%. Therefore, novel MPAOs containing active triazole rings, thioethers, Schiff bases, and BHT moieties are suggested as potential antioxidants for inhibiting oxidative stress processes and scavenging free radicals, hence, this combination of functions is anticipated to play a vital role in repairing cellular damage, preventing various human diseases and in medical therapeutic applications.

  6. Phosphonic Acid-Functionalized Polyurethane Dispersions with Improved Adhesion Properties.

    PubMed

    Breucker, Laura; Landfester, Katharina; Taden, Andreas

    2015-11-11

    A facile route to phosphorus-functionalized polyurethane dispersions (P-PUDs) with improved adhesion properties is presented. (Bis)phosphonic acid moieties serve as adhesion promoting sites that are covalently attached via an end-capping reaction to isocyanate-reactive polyurethane particles under aqueous conditions. The synthetic approach circumvents solubility issues, offers great flexibility in terms of polyurethane composition, and allows for the synthesis of semicrystalline systems with thermomechanical response due to reversible physical cross-linking. Differential scanning calorimetry (DSC) is used to investigate the effect of functionalization on the semicrystallinity. The end-capping conversion was determined via inductively-coupled plasma optical emission spectroscopy (ICP-OES) and was surprisingly found to be almost independent of the stoichiometry of reaction, suggesting an adsorption-dominated process. Particle charge detection (PCD) experiments reveal that a dense surface coverage of phosphonic acid groups can be attained and that, at high functionalization degrees, the phosphonic adhesion moieties are partially dragged inside the colloidal P-PUD particle. Quartz crystal microbalance with dissipation (QCMD) investigations conducted with hydroxyapatite (HAP) and stainless steel sensors as model surfaces show a greatly enhanced affinity of the aqueous P-PUDs and furthermore indicate polymer chain rearrangements and autonomous film formation under wet conditions. Due to their facile synthesis, significantly improved adhesion, and variable film properties, P-PUD systems such as the one described here are believed to be of great interest for multiple applications, e.g., adhesives, paints, anticorrosion, or dentistry.

  7. Tyrosine B10 triggers a heme propionate hydrogen bonding network loop with glutamine E7 moiety

    SciTech Connect

    Ramos-Santana, Brenda J.; Lopez-Garriga, Juan

    2012-08-10

    Highlights: Black-Right-Pointing-Pointer H-bonding network loop by PheB10Tyr mutation is proposed. Black-Right-Pointing-Pointer The propionate group H-bonding network restricted the flexibility of the heme. Black-Right-Pointing-Pointer The hydrogen bonding interaction modulates the electron density of the iron. Black-Right-Pointing-Pointer Propionate H-bonding network loop explains the heme-ligand stabilization. -- Abstract: Propionates, as peripheral groups of the heme active center in hemeproteins have been described to contribute in the modulation of heme reactivity and ligand selection. These electronic characteristics prompted the question of whether the presence of hydrogen bonding networks between propionates and distal amino acids present in the heme ligand moiety can modulate physiological relevant events, like ligand binding association and dissociation activities. Here, the role of these networks was evaluated by NMR spectroscopy using the hemoglobin I PheB10Tyr mutant from Lucina pectinata as model for TyrB10 and GlnE7 hemeproteins. {sup 1}H-NMR results for the rHbICN PheB10Tyr derivative showed chemical shifts of TyrB10 OH{eta} at 31.00 ppm, GlnE7 N{sub {epsilon}1}H/N{sub {epsilon}2}H at 10.66 ppm/-3.27 ppm, and PheE11 C{sub {delta}}H at 11.75 ppm, indicating the presence of a crowded, collapsed, and constrained distal pocket. Strong dipolar contacts and inter-residues crosspeaks between GlnE7/6-propionate group, GlnE7/TyrB10 and TyrB10/CN suggest that this hydrogen bonding network loop between GlnE7, TyrB10, 6-propionate group, and the heme ligand contribute significantly to the modulation of the heme iron electron density as well as the ligand stabilization mechanism. Therefore, the network loop presented here support the fact that the electron withdrawing character of the hydrogen bonding is controlled by the interaction of the propionates and the nearby electronic environments contributing to the modulation of the heme electron density state. Thus

  8. Polysiloxanes with a Phenol Moiety for Bilayer Photoresist Applications

    NASA Astrophysics Data System (ADS)

    Onishi, Yasunobu; Ushirogouchi, Touru; Horiguchi, Rumiko; Hayase, Shuzi

    1989-08-01

    Novel Polysiloxanes with a phenol pendant group were synthesized and applied to bilayer photoresists for g-line and deep-UV (248 nm) lithography. These polymers had adequate aqueous-base solubility and oxygen-RIE resistance to serve as the base resin component for top imaging resists in bilayer resist systems. One of these polysiloxanes was synthesized from chlorodiethoxyphenylsilane and m-trimethylsiloxychlobenzene. Others were synthesized from dichlorophenylsilane and phenol and phenols with a double bond moiety (eugenol, isoeugenol and m-isopropenylphenol). These polysiloxanes had from 9.8 wt.% to 13.1 wt.X Si content and displayed an oxygen-RIE resistance 10 times greater than novolak resin. The m.p. values for these polymers ranged from 30°C to 90°C. The UV transmittance value (at 248 nm, 1 micron thickness) were from 7 % to 76 X. Resists were prepared from these polysiloxanes and sensitizers. In g-line lithography, the sensitizer was naphthoquinonediazide. In deep-UV (248 nm) lithography, the sensitizer was selected from naphtoquinonediazide, diazide and diazo compounds. 0.5 micron line and space patterns were obtained, when the resist was exposed using a g-line stepper, and using a tetramethylammonium hydroxide solution (ca. 1.3 %). 0.4 micron line and space patterns were resolved, when the resist was exposed using a KrF excimer laser stepper, and developed using the same solution. The top layer pattern could be transferred to the bottom layer (hard baked positive resist OFPR-5000) using oxygen-RIE. The etching rate for the silicon containing resist was 35 nm/min, while that for OFPR-5000 was 555 nm/min. These polysiloxanes make it possible to obtain the fine pattern resolution required in VLSI processing.

  9. Mycobacterial lipid II is composed of a complex mixture of modified muramyl and peptide moieties linked to decaprenyl phosphate.

    PubMed

    Mahapatra, Sebabrata; Yagi, Tetsuya; Belisle, John T; Espinosa, Benjamin J; Hill, Preston J; McNeil, Michael R; Brennan, Patrick J; Crick, Dean C

    2005-04-01

    Structural analysis of compounds identified as lipid I and II from Mycobacterium smegmatis demonstrated that the lipid moiety is decaprenyl phosphate; thus, M. smegmatis is the first bacterium reported to utilize a prenyl phosphate other than undecaprenyl phosphate as the lipid carrier involved in peptidoglycan synthesis. In addition, mass spectrometry showed that the muropeptides from lipid I are predominantly N-acetylmuramyl-L-alanine-D-glutamate-meso-diaminopimelic acid-D-alanyl-D-alanine, whereas those isolated from lipid II form an unexpectedly complex mixture in which the muramyl residue and the pentapeptide are modified singly and in combination. The muramyl residue is present as N-acetylmuramic acid, N-glycolylmuramic acid, and muramic acid. The carboxylic functions of the peptide side-chains of lipid II showed three types of modification, with the dominant one being amidation. The preferred site for amidation is the free carboxyl group of the meso-diaminopimelic acid residue. Diamidated species were also observed. The carboxylic function of the terminal D-alanine of some molecules is methylated, as are all three carboxylic acid functions of other molecules. This study represents the first structural analysis of mycobacterial lipid I and II and the first report of extensive modifications of these molecules. The observation that lipid I was unmodified strongly suggests that the lipid II intermediates of M. smegmatis are substrates for a variety of enzymes that introduce modifications to the sugar and amino acid residues prior to the synthesis of peptidoglycan.

  10. Hot melt adhesive attachment pad

    NASA Technical Reports Server (NTRS)

    Fox, R. L.; Frizzill, A. W.; Little, B. D.; Progar, D. J.; Coultrip, R. H.; Couch, R. H.; Gleason, J. R.; Stein, B. A.; Buckley, J. D.; St.clair, T. L. (Inventor)

    1984-01-01

    A hot melt adhesive attachment pad for releasably securing distinct elements together is described which is particularly useful in the construction industry or a spatial vacuum environment. The attachment pad consists primarily of a cloth selectively impregnated with a charge of hot melt adhesive, a thermo-foil heater, and a thermo-cooler. These components are securely mounted in a mounting assembly. In operation, the operator activates the heating cycle transforming the hot melt adhesive to a substantially liquid state, positions the pad against the attachment surface, and activates the cooling cycle solidifying the adhesive and forming a strong, releasable bond.

  11. Carbonic anhydrase inhibitors with dual-tail moieties to match the hydrophobic and hydrophilic halves of the carbonic anhydrase active site.

    PubMed

    Tanpure, Rajendra P; Ren, Bin; Peat, Thomas S; Bornaghi, Laurent F; Vullo, Daniela; Supuran, Claudiu T; Poulsen, Sally-Ann

    2015-02-12

    We present a new approach to carbonic anhydrase II (CA II) inhibitor design that enables close interrogation of the regions of the CA active site where there is the greatest variability in amino acid residues among the different CA isozymes. By appending dual tail groups onto the par excellence CA inhibitor acetazolamide, compounds that may interact with the distinct hydrophobic and hydrophilic halves of the CA II active site were prepared. The dual-tail combinations selected included (i) two hydrophobic moieties, (ii) two hydrophilic moieties, and (iii) one hydrophobic and one hydrophilic moiety. The CA enzyme inhibition profile as well as the protein X-ray crystal structure of compound 3, comprising one hydrophobic and one hydrophilic tail moiety, in complex with CA II is described. This novel dual-tail approach has provided an enhanced opportunity to more fully exploit interactions with the CA active site by enabling these molecules to interact with the distinct halves of the active site. In addition to the dual-tail compounds, a corresponding set of single-tail derivatives was synthesized, enabling a comparative analysis of the single-tail versus dual-tail compound CA inhibition profile.

  12. Adult attachment and declining birthrates.

    PubMed

    Draper, Thomas W; Holman, Thomas B; White, Whitney; Grandy, Shannon

    2007-02-01

    Attachment scores for 658 young adults living in the U.S.A. were obtained using the Experiences in Close Relationships scale. The participants came from a subsample of the RELATE data set, who had also filled out the adult attachment measure. Those young adults living in Utah County, Utah, an area of the country with a higher than normal birthrate (88% members of the Church of Jesus Christ of Latter-day Saints), also had higher than average adult attachment scores. While the methodology was not sufficient to assess causal direction nor eliminate the possibility of unidentified influences, an undiscussed psychological factor, adult attachment, may play a role in the numerical declines observed among nonimmigrant communities in the USA and Europe.

  13. Social attachments and traumatic stress

    PubMed Central

    Bryant, Richard A.

    2016-01-01

    The extent to which we engage with our social world has been central to our survival as a species and, accordingly, is relevant to how we cope with trauma and adversity. This review summarises current knowledge about the importance of social connections from an evolutionary perspective, as well as integrating this with a discussion of prevailing attachment theories. Experimental research supporting the potential benefit of attachments for managing adversity are presented, along with a review of how these benefits are moderated by individual differences in attachment style. The potential impact of trauma on attachment systems, and the manner in which this can compound trauma stress is discussed. Finally, a broader overview of social network analysis is introduced and it is proposed that a more sociocentric framework of trauma response would promote a fuller understanding of how social processes moderate trauma response. PMID:26996531

  14. Theory of dissociative electron attachment: Biomolecules and clusters

    NASA Astrophysics Data System (ADS)

    Fabrikant, Ilya I.

    2015-01-01

    Very broad σ∗ resonances, which are responsible for threshold structures and dissociative attachment in electron collisions with hydrogen halides, are also important in electron-impact bond-breaking in nucleobases and amino acids. We investigate this mechanism in more detail by carrying out model calculations of the N-H bond breaking in the uracil molecule. Although the σ∗ resonance is extremely broad at the equilibrium nuclear geometry, it is stabilized fast when the N-H bond is stretched, and this produces a substantial dissociative attachment cross section. In addition, very pronounced vibrational Feshbach resonances are seen below vibrational excitation thresholds. To incorporate the effect of a cluster environment in the dissociative electron attachment process, we develop further the multiple scattering theory for this process and calculate the dissociative attachment cross section for the CF3Cl molecule embedded in the (H2O)6 cluster.

  15. Synthesis and hydrolysis behaviour of poly(ester anhydrides) from polylactone precursors containing alkenyl moieties.

    PubMed

    Korhonen, Harri; Hakala, Risto A; Helminen, Antti O; Seppälä, Jukka V

    2006-07-14

    Hydroxyl-group functional polylactones were prepared and converted to acid- terminated polyesters in a reaction with a series of alkenylsuccinic anhydrides containing 8, 12, or 18 carbons in their alkenyl chains. These polyester precursors were then linked into higher molecular weight poly(ester anhydrides) containing alkenyl moieties in their polyester blocks. The hydrolysis behaviour of the poly(ester anhydrides) was found to depend on the thermal properties of the polyester precursors. For poly(ester anhydrides) prepared from low molecular weight prepolymers with thermal transitions below 37 degrees C, the presence of hydrophobic alkenyl chains in the polyester precursors slowed the rate of weight loss. Poly(ester anhydrides) prepared from higher molecular weight prepolymers showed the opposite weight-loss behaviour; i.e., the crystallinity and thermal transitions of the alkenyl chain-containing poly(ester anhydrides) were low, and the weight loss was faster than for poly(ester anhydrides) without the alkenyl chains. The differences in length of the alkenyl chain, as such, had little effect on the hydrolysis behaviour and thermal properties of the poly(ester anhydrides).

  16. Synthesis, Characterization and Anti-Cancer Activity of Hydrazide Derivatives Incorporating a Quinoline Moiety.

    PubMed

    Bingul, Murat; Tan, Owen; Gardner, Christopher R; Sutton, Selina K; Arndt, Greg M; Marshall, Glenn M; Cheung, Belamy B; Kumar, Naresh; Black, David StC

    2016-07-14

    Identification of the novel (E)-N'-((2-chloro-7-methoxyquinolin-3-yl)methylene)-3-(phenylthio)propanehydrazide scaffold 18 has led to the development of a new series of biologically active hydrazide compounds. The parent compound 18 and new quinoline derivatives 19-26 were prepared from the corresponding quinoline hydrazones and substituted carboxylic acids using EDC-mediated peptide coupling reactions. Further modification of the parent compound 18 was achieved by replacement of the quinoline moiety with other aromatic systems. All the newly synthesized compounds were evaluated for their anti-cancer activity against the SH-SY5Y and Kelly neuroblastoma cell lines, as well as the MDA-MB-231 and MCF-7 breast adenocarcinoma cell lines. Analogues 19 and 22 significantly reduced the cell viability of neuroblastoma cancer cells with micromolar potency and significant selectivity over normal cells. The quinoline hydrazide 22 also induced G₁ cell cycle arrest, as well as upregulation of the p27(kip1) cell cycle regulating protein.

  17. Comparative screening of plant essential oils: phenylpropanoid moiety as basic core for antiplatelet activity.

    PubMed

    Tognolini, M; Barocelli, E; Ballabeni, V; Bruni, R; Bianchi, A; Chiavarini, M; Impicciatore, M

    2006-02-23

    Essential oils extracted from different plants (Anthemis nobilis L., Artemisia dracunculus L., Cannabis sativa L., Cupressus sempervirens L., Cymbopogon citratus (DC.) Stapf., Curcuma longa L., Foeniculum vulgare L., Hypericum perforatum L., Hyssopus officinalis L., Mentha spicata L., Monarda didyma L., Ocimum basilicum L., Ocotea quixos Kosterm., Origanum vulgare L., Pinus nigra J.F. Arnold, Pinus silvestris L., Piper crassinervium Kunth., Rosmarinus officinalis L., Salvia officinalis L., Salvia sclarea L., Santolina chamaecyparissus L., Thymus vulgaris L., Zingiber officinaie L.) were screened in guinea pig and rat plasma in order to assess antiplatelet activity and inhibition of clot retraction. The oils were chemically analysed and a relationship between components and ability to affect hemostasis was evidenced. O. quixos, F. vulgaris, and A. dracunculus showed the highest antiplatelet activity against ADP, Arachidonic Acid and the Thromboxane A2 agonist U46619 (IC50, 4-132 microg ml(-1)), and a good ability to destabilize clot retraction (IC50, 19-180 microg ml(-1)). For these oils a significant correlation between antiplatelet potency and phenylpropanoids content (54-86%) was evidenced thus suggesting a key role for this moiety in the prevention of clot formation. These findings provide the rationale to take in account the antiplatelet activity in the pharmacological screening of natural products containing phenylpropanoids.

  18. Activation of protein kinase C by the lipid moieties of lipopolysaccharide

    SciTech Connect

    Wightman, P.D.; Raetz, C.R.H.

    1986-03-01

    Protein kinase C (PKC) was partially purified from the RAW264.7 macrophage-like cell and characterized by its activation by phosphatidylserine (PS) in the presence of calcium and its insensitivity to cyclic nucleotides or calmodulin. This PKC can also be activated by the acidic lipid moieties of lipopolysaccharide (LPS). The LPS lipids activate PKC in the absence of PS and, like PS, synergize with diacylglycerol (DAG). Intact RAW264.7 cells were prelabelled with /sup 32/Pi and treated with the well characterized PKC ligands, phorbol myristate acetate (PMA) or DAG. The phosphoproteins thereby induced were separated in 2-D gels and visualized by autoradiography. These phosphoproteins were used as standards to identify the PKC-associated phosphoproteins induced in these cells using other stimulators. The authors demonstrate that the LPS lipids as well as LPS itself induce the formation of phosphoproteins common to those induced by PMA or DAG. PMA, DAG, the LPS lipids, and LPS itself activate the RAW264.7 cell and stimulate the release of prostaglandin D/sub 2/ at the same concentration that stimulate new protein phosphorylation. These results suggest that the activation of PKC is an early event in the activation of the RAW264.7 macrophage by LPS.

  19. Natural variability in acyl moieties of sugar esters produced by certain tobacco and other Solanaceae species.

    PubMed

    Kroumova, Antoaneta B M; Zaitlin, Dave; Wagner, George J

    2016-10-01

    A unique feature of glandular trichomes of plants in the botanical family Solanaceae is that they produce sugar esters (SE), chemicals that have been shown to possess insecticidal, antifungal, and antibacterial properties. Sugar esters of tobacco (Nicotiana tabacum) provide pest resistance, and are important flavor precursors in oriental tobacco cultivars. Acyl moieties of SEs in Nicotiana spp., petunia, and tomato are shown to vary with respect to carbon length and isomer structure (2-12 carbon chain length; anteiso-, iso-, and straight-chain). Sugar esters and their acyl groups could serve as a model to explore the basis of phenotypic diversity and adaptation to natural and agricultural environments. However, information on the diversity of acyl composition among species, cultivars, and accessions is lacking. Herein, described is the analysis of SE acyl groups found in 21 accessions of Nicotiana obtusifolia (desert tobacco), six of Nicotiana occidentalis subsp. hesperis, three of Nicotiana alata, two of N. occidentalis, four modern tobacco cultivars, five petunia hybrids, and one accession each of a primitive potato (Solanum berthaultii) and tomato (Solanum pennellii). A total of 20 different acyl groups was observed that were represented differently among cultivars, species, and accessions. In Nicotiana species, acetate and iso- and anteiso-branched acids prevailed. Straight-chain groups (2-8 carbons) were prominent in petunias, while octanoic acid was prominent in N. alata and N. × sanderae. Two unexpected acyl groups, 8-methyl nonanoate and decanoate were found in N. occidentalis subsp. hesperis. Longer chain groups were found in the petunia, tomato, and potato species studied.

  20. Electron attachment to PSCl3.

    PubMed

    Knighton, W B; Miller, Thomas M; Grimsrud, E P; Viggiano, A A

    2004-01-01

    Electron attachment to PSCl3 was studied in 133-Pa pressure of helium gas at temperatures from 298-550 K. Measurements of rate constants and branching fractions were made in a flowing-afterglow Langmuir-probe (FALP) apparatus. These experiments yielded an electron attachment rate constant of 5.1 x 10(-8) cm3 s(-1) that was found not to change significantly in the 298-550 K temperature range. This rate constant represents an attachment efficiency of about 14%. Attachment in 133 Pa of He gas yielded only the dissociative ion products PSCl2- and Cl-. The FALP data suggest that there is an activation energy of about 17 meV for production of PSCl2-. Attachment to PSCl3 was also studied at high pressure (9-93 kPa) of N2 in an ion mobility mass spectrometer, at 298 K. In contrast to the low-pressure data, the parent anion product channel (PSCl3-) was observed (along with the dissociative channels), and increased in importance with N2 pressure. Gaussian-3 (G3) calculations were carried out for PSCl3 and PSCl2 neutrals and anions to aid in interpretation of the experimental results. The calculations indicate that the electron affinity EA(PSCl2) is slightly smaller than EA(Cl), which may account for the observed branching fractions for PSCl2- and Cl- in the low-pressure experiments. A natural population analysis was performed to obtain the charges associated with each atom in the molecules in order to estimate how the attached electron is distributed. Comparison is made between the present study of electron attachment to PSCl3 and our earlier work on attachment to POCl3, and G3 calculations are reported here for neutral and anionic POCl2 and POCl3. In contrast to PSCl2, the calculations imply that EA(POCl2) is slightly greater than EA(Cl). For both PSCl3 and POCl3, the calculations show that the dissociative electron attachment process is close to thermoneutral.

  1. Electron attachment to PSCl3

    NASA Astrophysics Data System (ADS)

    Knighton, W. B.; Miller, Thomas M.; Grimsrud, E. P.; Viggiano, A. A.

    2004-01-01

    Electron attachment to PSCl3 was studied in 133-Pa pressure of helium gas at temperatures from 298-550 K. Measurements of rate constants and branching fractions were made in a flowing-afterglow Langmuir-probe (FALP) apparatus. These experiments yielded an electron attachment rate constant of 5.1×10-8cm3 s-1 that was found not to change significantly in the 298-550 K temperature range. This rate constant represents an attachment efficiency of about 14%. Attachment in 133 Pa of He gas yielded only the dissociative ion products PSCl2- and Cl-. The FALP data suggest that there is an activation energy of about 17 meV for production of PSCl2-. Attachment to PSCl3 was also studied at high pressure (9-93 kPa) of N2 in an ion mobility mass spectrometer, at 298 K. In contrast to the low-pressure data, the parent anion product channel (PSCl3-) was observed (along with the dissociative channels), and increased in importance with N2 pressure. Gaussian-3 (G3) calculations were carried out for PSCl3 and PSCl2 neutrals and anions to aid in interpretation of the experimental results. The calculations indicate that the electron affinity EA(PSCl2) is slightly smaller than EA(Cl), which may account for the observed branching fractions for PSCl2- and Cl- in the low-pressure experiments. A natural population analysis was performed to obtain the charges associated with each atom in the molecules in order to estimate how the attached electron is distributed. Comparison is made between the present study of electron attachment to PSCl3 and our earlier work on attachment to POCl3, and G3 calculations are reported here for neutral and anionic POCl2 and POCl3. In contrast to PSCl2, the calculations imply that EA(POCl2) is slightly greater than EA(Cl). For both PSCl3 and POCl3, the calculations show that the dissociative electron attachment process is close to thermoneutral.

  2. Activating Attachments Reduces Memories of Traumatic Images

    PubMed Central

    Foord, Rachael

    2016-01-01

    Emotional memories, and especially intrusive memories, are a common feature of many psychological disorders, and are overconsolidated by stress. Attachment theory posits that activation of mental representations of attachment figures can reduce stress and boost coping. This study tested the proposition that attachment activation would reduce consolidation of emotional and intrusive memories. Sixty-seven undergraduate students viewed subliminal presentations of traumatic and neutral images, which were preceded by subliminal presentations of either attachment-related images or non-attachment-related images; free recall and intrusive memories were assessed two days later. Participants with low avoidant attachment tendencies who received the attachment primes recalled fewer memories and reported fewer intrusions than those who received the non-attachment primes. Unexpectedly, those with high anxious attachment tendencies reported fewer memories. These findings generally accord with attachment theory, and suggest that consolidation of emotional memories can be moderated by activation of attachment representations. PMID:27631498

  3. Syntheses and antiproliferative activities of novel phosphatidylcholines containing dehydroepiandrosterone moieties.

    PubMed

    Kłobucki, Marek; Grudniewska, Aleksandra; Smuga, Damian A; Smuga, Małgorzata; Jarosz, Joanna; Wietrzyk, Joanna; Maciejewska, Gabriela; Wawrzeńczyk, Czesław

    2017-02-01

    Dehydroepiandrosterone (DHEA) is a natural hormone with many beneficial properties including an anticancer activity. Unfortunately, DHEA is unstable in the body and exhibits cytotoxicity against healthy cells. In this study, a series of new phosphocholines containing DHEA at sn-1 and/or sn-2 positions were prepared. Succinic acid was used as a linker between the active drug and sn-glycero-3-phosphocholine. All the compounds were evaluated in vitro for their antiproliferative activities against four cell lines: Balb/3T3, HL-60, B16, and LNCaP. The results showed that phosphocholines with DHEA at sn-1 and/or sn-2 positions did not have cytotoxic effects on the normal cell line (Balb/3T3). Mixed-chain phospholipids with DHEA and fatty acid residues showed the highest activity against tumor cell lines. The most active compound, 11c, showed a moderate cytotoxic effect against the HL-60 and B16 cell lines.

  4. Structure-performance correlations of organic dyes with an electron-deficient diphenylquinoxaline moiety for dye-sensitized solar cells.

    PubMed

    Li, Sie-Rong; Lee, Chuan-Pei; Yang, Po-Fan; Liao, Chia-Wei; Lee, Mandy M; Su, Wei-Lin; Li, Chun-Ting; Lin, Hao-Wu; Ho, Kuo-Chuan; Sun, Shih-Sheng

    2014-08-04

    The high performances of dye-sensitized solar cells (DSSCs) based on seven new dyes are disclosed. Herein, the synthesis and electrochemical and photophysical properties of a series of intentionally designed dipolar organic dyes and their application in DSSCs are reported. The molecular structures of the seven organic dyes are composed of a triphenylamine group as an electron donor, a cyanoacrylic acid as an electron acceptor, and an electron-deficient diphenylquinoxaline moiety integrated in the π-conjugated spacer between the electron donor and acceptor moieties. The DSSCs based on the dye DJ104 gave the best overall cell performance of 8.06 %; the efficiency of the DSSC based on the standard N719 dye under the same experimental conditions was 8.82 %. The spectral coverage of incident photon-to-electron conversion efficiencies extends to the onset at the near-infrared region due to strong internal charge-transfer transition as well as the effect of electron-deficient diphenylquinoxaline to lower the energy gap in these organic dyes. A combined tetraphenyl segment as a hydrophobic barrier in these organic dyes effectively slows down the charge recombination from TiO2 to the electrolyte and boosts the photovoltage, comparable to their Ru(II) counterparts. Detailed spectroscopic studies have revealed the dye structure-cell performance correlations, to allow future design of efficient light-harvesting organic dyes.

  5. Novel TSAO derivatives modified at positions 3" and 4" of the spiro moiety.

    PubMed

    Lobatón, E; Velázquez, S; San-Félix, A; Chamorro, C; Tuñón, V; Esteban-Gamboa, A; De Clercq, E; Balzarini, J; Camarasa, M J; Pérez-Pérez, M J

    1999-01-01

    We have explored the introduction of different functional groups at positions 3" and 4" of the spiro moiety of TSAO-T. Alkylation of this spiro moiety afforded mixtures of N and/or C-alkylated derivatives, while acylation occurs, exclusively, on the amino group. Position 3" has been selectively functionalized by halogenation followed by Stille-cross coupling reaction with organostannanes under a variety of experimental conditions.

  6. Transfer of the phosphatidyl moiety of phosphatidylglycerol to phosphatidylethanolamine in Escherichia coli.

    PubMed Central

    Yokota, K; Kito, M

    1982-01-01

    Phosphatidylglycerol was pulse-labeled with radioactive lipid precursors in a serine auxotroph of Escherichia coli. Most of the radioactivity of phosphatidylglycerol labeled in a serine-depleted medium was transferred to phosphatidylethanolamine during a chase in the presence of L-serine, but not in its absence. Metabolism of fatty acyl moieties labeled with [1-14C]acetate, acylated glycerol moieties labeled with [2-3H]glycerol, and phosphate moieties labeled with 32Pi, followed by a chase in the presence of cerulenin, showed that the intact phosphatidyl moiety of phosphatidylglycerol was transferred to phosphatidylethanolamine. The composition of phosphatidylethanolamine molecular species was unaltered and not perturbed by the transfer of the phosphatidyl moiety of phosphatidylglycerol. The increase of phosphatidylethanolamine with a concomitant decrease of phosphatidylglycerol was not coupled with the postulated turnover of phosphatidylglycerol to membrane-derived oligosaccharides and lipoprotein. It is suggested that phosphatidylglycerol is capable of providing its phosphatidyl moiety for the production of phosphatidylethanolamine in response to the relief of serine limitation by addition of L-serine. PMID:6807966

  7. 10 CFR 75.15 - Facility attachments.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 2 2010-01-01 2010-01-01 false Facility attachments. 75.15 Section 75.15 Energy NUCLEAR... Accounting and Control for Facilities § 75.15 Facility attachments. (a) The Facility Attachment or Transitional Facility Attachment will document the determinations referred to in § 75.10 and will contain...

  8. Attachment Processes in Eating Disorder and Depression.

    ERIC Educational Resources Information Center

    Cole-Detke, Holland; Kobak, Roger

    1996-01-01

    Examines the relationship between attachment strategies and symptom reporting among college women (N=61). The Adult Attachment Interview (AAI) was administered and interview transcripts were rated with the Attachment Interview Q-Sort. Findings support the hypothesis that secondary or defensive attachment strategies predispose individuals toward…

  9. Novel Natural Product-like Caged Xanthones Bearing a Carbamate Moiety Exhibit Antitumor Potency and Anti-Angiogenesis Activity In vivo

    PubMed Central

    Xu, Xiaoli; Wu, Yue; Hu, Mingyang; Li, Xiang; Bao, Qichao; Bian, Jinlei; You, Qidong; Zhang, Xiaojin

    2016-01-01

    DDO-6101, a simplified structure obtained from the Garcinia natural product (NP) gambogic acid (GA), has been previously shown to possess high cytotoxicity to a variety of human tumour cell lines. To improve its physicochemical properties and in vivo cytotoxic potency, a series of novel carbamate-bearing derivatives based on DDO-6101 was synthesized and characterized. The structural modifications revealed that the presence of a carbamate moiety was useful for obtaining comparable cytotoxicity and improved aqueous solubility and permeability. 8n, which contains a bipiperidine carbamate moiety, displayed better drug properties and potential in in vivo antitumor activity. In addition, an antitumor mechanistic study suggested that 8n (DDO-6337) inhibited the ATPase activity of Hsp90 (Heat shock protein 90), leading to the inhibition of HIF-1a and ultimately contributing to its anti-angiogenesis and antitumor properties. PMID:27767192

  10. To Be Attached and Free.

    ERIC Educational Resources Information Center

    Maier, Henry W.

    1987-01-01

    Reviews recent research showing that child and parent, or caregiver and care receiver in nonfamilial, group settings, need each other reciprocally and need to find mutual fit. Focuses on stress laid on importance of dependence support, attachment behavior, and mutuality of caregiver and care receiver. Discusses effect of day care and significance…

  11. Synthesis and antioxidant activity of some 1-aryl/aralkyl piperazine derivatives with xanthine moiety at N4

    PubMed Central

    Andonova, Lily; Zheleva-Dimitrova, Dimitrina; Georgieva, Maya; Zlatkov, Alexander

    2014-01-01

    Piperazine nucleus is one of the most important heterocyclic systems exhibiting remarkable pharmacological activities. Thus, in the current study six new aryl/aralkyl substituted piperazine derivatives, containing methylxanthine moiety were synthesized and their structures were confirmed by IR and 1H NMR analysis. All compounds were in vitro screened for their activity as antioxidants using DPPH (2,2′-Diphenyl-1-picrylhydrazyl), ABTS (2,2′-azinobis-(3-ethylbenzo thiazine-6-sulfonic acid)) and FRAP (ferric reducing/antioxidant power) methods. The antioxidant activity of the studied compounds against lipid peroxidation was also measured. The highest antioxidant activity was demonstrated by compound 3c. It is obvious that the presence of a hydroxyl group in the structure is essential for the antioxidant properties and should be taken into consideration in further design of structures with potential antioxidant properties. PMID:26019603

  12. Synthesis and Evaluation of a Series of Oleanolic Acid Saponins as α-Glucosidase and α-Amylase Inhibitors.

    PubMed

    Guo, Tiantian; Wu, Shaoping; Guo, Sen; Bai, Lu; Liu, Qingchao; Bai, Naisheng

    2015-09-01

    Sixteen naturally occurring oleanolic acid saponins and their derivatives were synthesized in an efficient and practical strategy, and their inhibitory activities against α-glucosidase and α-amylase were evaluated in vitro. Among all the compounds, 28-O-monoglucoside 8 exhibited remarkably potent inhibitory activity against α-glucosidase with an IC50 value of 87.3 µM, which was fivefold stronger than that of the antidiabetic acarbose. Based on the preliminary structure-activity relationships, for 28-O-monoglucosides, the presence of a terminal α-l-rhamnopyranosyl residue enhanced the α-glucosidase and α-amylase inhibitory activities. Furthermore, for 3,28-O-bidesmosides, sugar-substituted moieties attached to the C-3 and C-28 positions of the oleanolic acid scaffold are helpful to increase the inhibitory activities against α-amylase and α-glucosidase.

  13. Anacardic Acid, Salicylic Acid, and Oleic Acid Differentially Alter Cellular Bioenergetic Function in Breast Cancer Cells.

    PubMed

    Radde, Brandie N; Alizadeh-Rad, Negin; Price, Stephanie M; Schultz, David J; Klinge, Carolyn M

    2016-11-01

    Anacardic acid is a dietary and medicinal phytochemical that inhibits breast cancer cell proliferation and uncouples oxidative phosphorylation (OXPHOS) in isolated rat liver mitochondria. Since mitochondrial-targeted anticancer therapy (mitocans) may be useful in breast cancer, we examined the effect of anacardic acid on cellular bioenergetics and OXPHOS pathway proteins in breast cancer cells modeling progression to endocrine-independence: MCF-7 estrogen receptor α (ERα)+ endocrine-sensitive; LCC9 and LY2 ERα+, endocrine-resistant, and MDA-MB-231 triple negative breast cancer (TNBC) cells. At concentrations similar to cell proliferation IC50 s, anacardic acid reduced ATP-linked oxygen consumption rate (OCR), mitochondrial reserve capacity, and coupling efficiency while increasing proton leak, reflecting mitochondrial toxicity which was greater in MCF-7 compared to endocrine-resistant and TNBC cells. These results suggest tolerance in endocrine-resistant and TNBC cells to mitochondrial stress induced by anacardic acid. Since anacardic acid is an alkylated 2-hydroxybenzoic acid, the effects of salicylic acid (SA, 2-hydroxybenzoic acid moiety) and oleic acid (OA, monounsaturated alkyl moiety) were tested. SA inhibited whereas OA stimulated cell viability. In contrast to stimulation of basal OCR by anacardic acid (uncoupling effect), neither SA nor OA altered basal OCR- except OA inhibited basal and ATP-linked OCR, and increased ECAR, in MDA-MB-231 cells. Changes in OXPHOS proteins correlated with changes in OCR. Overall, neither the 2-hydroxybenzoic acid moiety nor the monounsaturated alky moiety of anacardic acid is solely responsible for the observed mitochondria-targeted anticancer activity in breast cancer cells and hence both moieties are required in the same molecule for the observed effects. J. Cell. Biochem. 117: 2521-2532, 2016. © 2016 Wiley Periodicals, Inc.

  14. Corrosion of coupled metals in a dental magnetic attachment system.

    PubMed

    Iimuro, F T; Yoneyama, T; Okuno, O

    1993-12-01

    Implants and magnetic attachments are becoming widespread in dental treatment. Their associated use, implants and magnetic attachments, can be seen often too. In those cases, it is difficult to avoid coupling of different metals. The corrosion behavior of the metals is expected to be different depending on whether it is found in an isolated or a coupled condition. Potential corrosion couples in a dental magnetic attachment system among titanium, ferromagnetic stainless steel, gold alloy type IV, and gold-silver-palladium alloy were studied by an immersion test in 1% lactic acid for 7 days and potential/current density curves were measured. Corrosion of titanium and ferromagnetic stainless steel seemed to be accelerated by coupling with gold alloys or gold-silver-palladium alloys. On the other hand, the corrosion amount of gold alloy and gold-silver-palladium alloys were attenuated by coupling.

  15. Dissociative attachment reactions of electrons with gas phase superacids

    SciTech Connect

    Liu, X.

    1992-01-01

    Using the flowing afterglow Langmuir probe (FALP) technique, dissociative attachment coefficients [beta] for reactions of electrons with gas phase superacids HCo(PF[sub 3])[sub 4], HRh(PF[sub 3])[sub 4] and carbonyl hydride complexes HMn(CO)[sub 5], HRe(CO)[sub 5] have been determined under thermal conditions over the approximate temperature range 300[approximately]550 K. The superacids react relatively slowly (<1/20 of [beta][sub max]) with free electrons in a thermal plasma, and the values of [beta] obtained this far do not show a correlation between acidity and [beta]. The pioneer researchers in this field had speculated that any superacid would be a rapid attacher of electrons; it was found that this speculation is not true in general. The product distribution of electron attachment reaction to HCo(PF[sub 3])[sub 4] was found to be independent of temperature even though the [beta][HCo(PF[sub 3])[sub 4

  16. Characterisation of the Native Lipid Moiety of Echinococcus granulosus Antigen B

    PubMed Central

    Obal, Gonzalo; Ramos, Ana Lía; Silva, Valeria; Lima, Analía; Batthyany, Carlos; Bessio, María Inés; Ferreira, Fernando; Salinas, Gustavo; Ferreira, Ana María

    2012-01-01

    Antigen B (EgAgB) is the most abundant and immunogenic antigen produced by the larval stage (metacestode) of Echinococcus granulosus. It is a lipoprotein, the structure and function of which have not been completely elucidated. EgAgB apolipoprotein components have been well characterised; they share homology with a group of hydrophobic ligand binding proteins (HLBPs) present exclusively in cestode organisms, and consist of different isoforms of 8-kDa proteins encoded by a polymorphic multigene family comprising five subfamilies (EgAgB1 to EgAgB5). In vitro studies have shown that EgAgB apolipoproteins are capable of binding fatty acids. However, the identity of the native lipid components of EgAgB remains unknown. The present work was aimed at characterising the lipid ligands bound to EgAgB in vivo. EgAgB was purified to homogeneity from hydatid cyst fluid and its lipid fraction was extracted using chloroform∶methanol mixtures. This fraction constituted approximately 40–50% of EgAgB total mass. High-performance thin layer chromatography revealed that the native lipid moiety of EgAgB consists of a variety of neutral (mainly triacylglycerides, sterols and sterol esters) and polar (mainly phosphatidylcholine) lipids. Gas-liquid chromatography analysis showed that 16∶0, 18∶0 and 18∶1(n-9) are the most abundant fatty acids in EgAgB. Furthermore, size exclusion chromatography coupled to light scattering demonstrated that EgAgB comprises a population of particles heterogeneous in size, with an average molecular mass of 229 kDa. Our results provide the first direct evidence of the nature of the hydrophobic ligands bound to EgAgB in vivo and indicate that the structure and composition of EgAgB lipoprotein particles are more complex than previously thought, resembling high density plasma lipoproteins. Results are discussed considering what is known on lipid metabolism in cestodes, and taken into account the Echinococcus spp. genomic information regarding both lipid

  17. Infant Day Care and Attachment.

    ERIC Educational Resources Information Center

    Caldwell, Bettye M.; And Others

    In a longitudinal study, a group of 41 children from lower class families were examined for differences in child-mother and mother-child attachment patterns at 30 months of age. Twenty-three children had been cared for by their mothers from birth until 30 months of age, and 18 had been enrolled in a day care center for at least 1 year. Data…

  18. Trauma, attachment, and intimate relationships.

    PubMed

    Zurbriggen, Eileen L; Gobin, Robyn L; Kaehler, Laura A

    2012-01-01

    Intimate relationships can both affect and be affected by trauma and its sequelae. This special issue highlights research on trauma, attachment, and intimate relationships. Several themes emerged. One theme is the exploration of the associations between a history of trauma and relational variables, with an emphasis on models using these variables as mediators. Given the significance of secure attachment for healthy relationships, it is not surprising that attachment emerges as another theme of this issue. Moreover, a key component of relationships is trust, and so a further theme of this issue is betrayal trauma (J. J. Freyd, 1996 ). As the work included in this special issue makes clear, intimate relationships of all types are important for the psychological health of those exposed to traumatic events. In order to best help trauma survivors and those close to them, it is imperative that research exploring these issues be presented to research communities, clinical practitioners, and the public in general. This special issue serves as one step toward that objective.

  19. Ascorbic acid conjugates isolated from the phloem of Cucurbitaceae.

    PubMed

    Hancock, Robert D; Chudek, John A; Walker, Paul G; Pont, Simon D A; Viola, Roberto

    2008-06-01

    Analysis of phloem exudates from the fruit of Cucurbitaceae revealed the presence of several compounds with UV-visible absorption spectra identical to that of l-ascorbic acid. In Cucurbita pepo L. (zucchini), the compounds could be isolated from phloem exudates collected from aerial parts of the plant but were not detected in whole tissue homogenates. The compounds isolated from the phloem exudates of C. pepo fruit were eluted from strong anion exchange resin in the same fraction as l-ascorbic acid and were oxidised by ascorbate oxidase (E.C. 1.10.3.3). The major compound purified from C. pepo fruit exudates demonstrated similar redox properties to l-ascorbic acid and synthetic 6-O-glucosyl-l-ascorbic acid (6-GlcAsA) but differed from those of 2-O-glucosyl-l-ascorbic acid (2-GlcAsA) isolated from the fruit of Lycium barbarum L. Parent and fragment ion masses of the compound were consistent with hexosyl-ascorbate in which the hexose moiety was attached to C5 or C6 of AsA. Acid hydrolysis of the major C. pepo compound resulted in the formation of l-ascorbic acid and glucose. The purified compound yielded a proton NMR spectrum that was almost identical to that of synthetic 6-GlcAsA. A series of l-ascorbic acid conjugates have, therefore, been identified in the phloem of Cucurbitaceae and the most abundant conjugate has been identified as 6-GlcAsA. The potential role of such conjugates in the long-distance transport of l-ascorbic acid is discussed.

  20. Identification of the dioxygenase-generated intermediate formed during biosynthesis of the dihydropyrrole moiety common to anthramycin and sibiromycin

    PubMed Central

    Saha, Shalini; Li, Wei; Gerratana, Barbara; Rokita, Steven E.

    2015-01-01

    A description of pyrrolo[1,4]benzodiazepine (PBD) biosynthesis is a prerequisite for engineering production of analogs with enhanced antitumor activity. Predicted dioxygenases Orf12 and SibV associated with dihydropyrrole biosynthesis in PBDs anthramycin and sibiromycin, respectively, were expressed and purified for activity studies. UV-visible spectroscopy revealed that these enzymes catalyze the regiospecific 2,3-extradiol dioxygenation of L-3,4-dihydroxyphenylalanine (L-DOPA) to form L-2,3-secodopa (λmax = 368 nm). 1H NMR spectroscopy indicates that L-2,3-secodopa cyclizes into the α-keto acid tautomer of L-4-(2-oxo-3-butenoic-acid)-4,5-dihydropyrrole-2-carboxylic acid (λmax = 414 nm). Thus, the dioxygenases are key for establishing the scaffold of the dihydropyrrole moiety. Kinetic studies suggest the dioxygenase product is relatively labile and is likely consumed rapidly by subsequent biosynthetic steps. The enzymatic product and dimeric state of these dioxygenases are conserved in dioxygenases involved in dihydropyrrole or pyrrolidine biosynthesis within both PBD and non-PBD pathways. PMID:25564379

  1. Emanuel Miller Lecture: Attachment Insecurity, Disinhibited Attachment, and Attachment Disorders--Where Do Research Findings Leave the Concepts?

    ERIC Educational Resources Information Center

    Rutter, Michael; Kreppner, Jana; Sonuga-Barke, Edmund

    2009-01-01

    Background: Despite the evidence on anomalous attachment patterns, there has been a tendency to interpret most of these as reflecting differences in security/insecurity. Methods: Empirical research findings are reviewed in relation to attachment/insecurity as evident in both infancy and later childhood, disorganised attachment, inhibited…

  2. 78 FR 52868 - Pole Attachment Complaint Procedures

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-08-27

    ... From the Federal Register Online via the Government Publishing Office FEDERAL COMMUNICATIONS COMMISSION 47 CFR Part 1 Pole Attachment Complaint Procedures AGENCY: Federal Communications Commission... regulations concerning pole attachments outlined in the DATES section. DATES: Effective August 27, 2013,...

  3. Attaching Chuck Keys to Machine Tools

    NASA Technical Reports Server (NTRS)

    Richardson, V.

    1984-01-01

    Chuck keys attached to portable machine tools by retracting lanyards. Lanyard held taut by recoil caddy attached to tool base. Chuck key available for use when needed and safely secured during operation of tool.

  4. Fluorescent Sensing of Guanine and Guanosine Monophosphate with Conjugated Receptors Incorporating Aniline and Naphthyridine Moieties.

    PubMed

    Lu, Shao-Hung; Phang, Riping; Fang, Jim-Min

    2016-04-15

    Ethyne-linked naphthyridine-aniline conjugated molecules are selective sensors of decylguanine in dichloromethane and guanosine monophosphate in water (Kass = 16,000 M(-1)). The 2-acetamido-1,8-naphthyridine moiety binds with guanine in a DAA-ADD triply hydrogen-bonded motif. The aniline moiety enhances an electron-donating effect, and the substituent is tuned to attain extra hydrogen bonds, π-π stacking, and electrostatic interactions. The proposed binding modes are supported by a Job plot, ESI-MS, (1)H NMR, UV-vis, and fluorescence spectral analyses.

  5. 14 CFR 33.25 - Accessory attachments.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Accessory attachments. 33.25 Section 33.25... STANDARDS: AIRCRAFT ENGINES Design and Construction; General § 33.25 Accessory attachments. The engine must operate properly with the accessory drive and mounting attachments loaded. Each engine accessory drive...

  6. Easy Attachment Of Panels To A Truss

    NASA Technical Reports Server (NTRS)

    Thomson, Mark; Gralewski, Mark

    1992-01-01

    Conceptual antenna dish, solar collector, or similar structure consists of hexagonal panels supported by truss erected in field. Truss built in increments to maintain access to panel-attachment nodes. Each panel brought toward truss at angle and attached to two nodes. Panel rotated into attachment at third node.

  7. Attachment Relationships and the Career Exploration Process.

    ERIC Educational Resources Information Center

    Ketterson, Timothy U.; Blustein, David L.

    1997-01-01

    Examines the role of parent-adolescent attachment relationships in the career exploration process. Results, based on 137 college students, indicate that attachment to parents is positively associated with environmental exploration. However, parental attachment did not influence traditionality of exploration. Age played a significant role in career…

  8. Genetic and Environmental Influence on Attachment Disorganization

    ERIC Educational Resources Information Center

    Spangler, Gottfried; Johann, Monika; Ronai, Zsolt; Zimmermann, Peter

    2009-01-01

    Background: Empirical studies demonstrate that maternal sensitivity is associated with attachment security in infancy, while maternal frightening/frightened behavior is related to attachment disorganization. However, attachment disorganization is also predicted by individual dispositions in infancy. Indeed, recent studies indicate a link between…

  9. Attachment in Deaf Mothers and Their Children

    ERIC Educational Resources Information Center

    Leigh, Irene W.; Brice, Patrick J.; Meadow-Orlans, Kathryn

    2004-01-01

    In attachment research, there has been a growing interest in how adults conceptualize their relationships with their own parents as well as in the transmission of attachment status from parent to child and the variables that influence that transmission. The primary goal of the present study was to examine the transmission of attachment from deaf…

  10. Attachment Representation of Institutionalized Children in Japan

    ERIC Educational Resources Information Center

    Katsurada, Emiko

    2007-01-01

    This exploratory study represents one of the first attachment investigations of Japanese children who have been institutionalized. Mental representation of attachment was assessed using George and Solomon's (1990, 1996, 2000) Attachment Doll Play Classification System of the Bretherton et al. (1990) doll play story stems. Participants were 32…

  11. Attachment: Building Secure Relationships in Early Childhood.

    ERIC Educational Resources Information Center

    Harrison, Linda

    2003-01-01

    Attachment describes the unique human ability to form lasting relationships with others, and to maintain these relationships over time and distance. Research into attachment has shown that children have the potential to form many attachment relationships, and that each relationship can contribute to the child's growing sense of self. This booklet…

  12. Attachment in Middle Childhood: Progress and Prospects

    ERIC Educational Resources Information Center

    Bosmans, Guy; Kerns, Kathryn A.

    2015-01-01

    Contrary to the substantial amount of research on infant, preschool, adolescent, and adult attachment, middle childhood has long been neglected by the international attachment research community. In the past two decades, however, there has been a steep increase in research focusing on middle childhood attachment. This article provides an overview…

  13. Cesarean Births and Attachment Behaviors of Fathers.

    DTIC Science & Technology

    1984-01-01

    Apgar scores are 7 or greater at both 1 and 5...status, indications for cesarean delivery, anesthesis, and infant’s gestational age, birth weight, and apgar scores . Prior to meeting the father, the...delivery and attachment score ; highest school grade completed and attachment score ; and age and child care experience of the father and attachment score

  14. 10 CFR 75.15 - Facility attachments.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 10 Energy 2 2013-01-01 2013-01-01 false Facility attachments. 75.15 Section 75.15 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) SAFEGUARDS ON NUCLEAR MATERIAL-IMPLEMENTATION OF US/IAEA AGREEMENT Material Accounting and Control for Facilities § 75.15 Facility attachments. (a) The Facility Attachment...

  15. 10 CFR 75.15 - Facility attachments.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 10 Energy 2 2012-01-01 2012-01-01 false Facility attachments. 75.15 Section 75.15 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) SAFEGUARDS ON NUCLEAR MATERIAL-IMPLEMENTATION OF US/IAEA AGREEMENT Material Accounting and Control for Facilities § 75.15 Facility attachments. (a) The Facility Attachment...

  16. 10 CFR 75.15 - Facility attachments.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 2 2014-01-01 2014-01-01 false Facility attachments. 75.15 Section 75.15 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) SAFEGUARDS ON NUCLEAR MATERIAL-IMPLEMENTATION OF US/IAEA AGREEMENT Material Accounting and Control for Facilities § 75.15 Facility attachments. (a) The Facility Attachment...

  17. 10 CFR 75.15 - Facility attachments.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 2 2011-01-01 2011-01-01 false Facility attachments. 75.15 Section 75.15 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) SAFEGUARDS ON NUCLEAR MATERIAL-IMPLEMENTATION OF US/IAEA AGREEMENT Material Accounting and Control for Facilities § 75.15 Facility attachments. (a) The Facility Attachment...

  18. 21 CFR 872.3165 - Precision attachment.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Precision attachment. 872.3165 Section 872.3165...) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3165 Precision attachment. (a) Identification. A precision attachment or preformed bar is a device made of austenitic alloys or alloys containing 75...

  19. Reactive Attachment Disorder: Recommendations for School Counselors.

    ERIC Educational Resources Information Center

    Hayes, Susanna H.

    1997-01-01

    Using a case study, explores a unique counseling relationship. Examines how the quality of parent-child attachment and care of a child during the formative preschool years affects interpersonal relationship skills and school adjustment. Discusses reactive attachment disorders, the pervasiveness of attachment disorders, and recommendations for…

  20. 21 CFR 872.3165 - Precision attachment.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Precision attachment. 872.3165 Section 872.3165...) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3165 Precision attachment. (a) Identification. A precision attachment or preformed bar is a device made of austenitic alloys or alloys containing 75...

  1. Loneliness and Attachment Patterns in Young Adults.

    ERIC Educational Resources Information Center

    Hecht, Diana Taylor; Baum, Steven K.

    1984-01-01

    Investigated the relationship between loneliness and patterns of attachment in 47 college students. Results revealed a moderate to strong relationship between feeling lonely and early disrupted attachment, consistent with the notion that underlying attachment disorders may affect psychological development and social behavior. (JAC)

  2. Evidence that the serotype b antigenic determinant of Actinobacillus actinomycetemcomitans Y4 resides in the polysaccharide moiety of lipopolysaccharide.

    PubMed Central

    Wilson, M E; Schifferle, R E

    1991-01-01

    A high-molecular-weight polysaccharide-containing antigen was isolated from a phenol-water extract of Actinobacillus actinomycetemcomitans ATCC 43718 (formerly Y4) by gel permeation chromatography in lipopolysaccharide (LPS)-disaggregating buffer. The polysaccharide antigen formed a precipitin band with rabbit serotype b-specific antiserum but not with rabbit antisera to serotype a or c. Electroblotted serotype b antigen was probed with serum from a patient with localized juvenile periodontitis (LJP), resulting in a diffuse "smear" in the upper region of the lane. By utilizing an enzyme-linked immunosorbent assay, it was demonstrated that the geometric mean immunoglobulin G antibody titer to the serotype b polysaccharide was significantly higher in sera from LJP patients than in sera from periodontally healthy individuals. Moreover, LJP antibody titers to the serotype b polysaccharide exhibited age-dependent variation. Double immunodiffusion analysis revealed that the serotype b antigen formed a line of identity with low-molecular-weight LPS following reaction with serotype b-specific antiserum. Incubation of LJP serum in the presence of a lipid-free polysaccharide moiety obtained by mild acid hydrolysis of LPS from A. actinomycetemcomitans Y4 markedly reduced immunoglobulin G titer to the serotype b antigen. In contrast, solubilized lipid A was only weakly inhibitory. The results of this study indicate that the serotype b-specific determinant of A. actinomycetemcomitans resides in the polysaccharide moiety of LPS and represents a major target for immunoglobulin G antibody in serum of LJP subjects colonized by this organism. Images PMID:1706323

  3. Specific membrane binding of factor VIII is mediated by O-phospho-L-serine, a moiety of phosphatidylserine.

    PubMed

    Gilbert, G E; Drinkwater, D

    1993-09-21

    Phosphatidylserine, a negatively charged lipid, is exposed on the platelet membrane following cell stimulation, correlating with the expression of factor VIII receptors. We have explored the importance of the negative electrostatic potential of phosphatidylserine vs chemical moieties of phosphatidylserine for specific membrane binding of factor VIII. Fluorescein-labeled factor VIII bound to membranes containing 15% phosphatidic acid, a negatively charged phospholipid, with low affinity compared to phosphatidylserine-containing membranes. Binding was not specific as it was inhibited by other proteins in plasma. Factor VIII bound to membranes containing 10% phosphatidylserine in spite of a varying net charge provided by 0-15% stearylamine, a positively charged lipid. The soluble phosphatidylserine moiety, O-phospho-L-serine, inhibited factor VIII binding to phosphatidylserine-containing membranes with a Ki of 20 mM, but the stereoisomer, O-phospho-D-serine, was 5-fold less effective. Furthermore, binding of factor VIII to membranes containing synthetic phosphatidyl-D-serine was 5-fold less than binding to membranes containing phosphatidyl-L-serine. Membranes containing synthetic phosphatidyl-L-homoserine, differing from phosphatidylserine by a single methylene, supported high-affinity binding, but it was not specific as factor VIII was displaced by other plasma proteins. O-Phospho-L-serine also inhibited the binding of factor VIII to platelet-derived microparticles with a Ki of 20 mM, and the stereoisomer was 4-fold less effective. These results indicate that membrane binding of factor VIII is mediated by a stereoselective recognition O-phospho-L-serine of phosphatidylserine and that negative electrostatic potential is of lesser importance.

  4. A sensitive liquid chromatography/mass spectrometry-based assay for quantitation of amino-containing moieties in lipid A

    PubMed Central

    Kalhorn, Thomas F.; Kiavand, Anahita; Cohen, Ilana E.; Nelson, Amanda K.; Ernst, Robert K.

    2009-01-01

    A novel sensitive liquid chromatography/mass spectrometry-based assay was developed for the quantitation of aminosugars, including 2-amino-2-deoxyglucose (glucosamine, GlcN), 2-amino-2-deoxygalactose (galactosamine, GalN), and 4-amino-4-deoxyarabinose (aminoarabinose, AraN), and for ethanolamine (EtN), present in lipid A. This assay enables the identification and quantitation of all amino-containing moieties present in lipopolysaccharide or lipid A from a single sample. The method was applied to the analysis of lipid A (endotoxin) isolated from a variety of biosynthetic and regulatory mutants of Salmonella enterica serovar Typhimurium and Francisella tularensis subspecies novicida. Lipid A is treated with trifluoroacetic acid to liberate and deacetylate individual aminosugars and mass tagged with 6-aminoquinolyl-N-hydroxysuccinimidyl carbamate, which reacts with primary and secondary amines. The derivatives are separated using reversed-phase chromatography and analyzed using a single quadrupole mass spectrometer to detect quantities as small as 20 fmol. GalN was detected only in Francisella and AraN only in Salmonella, while GlcN was detected in lipid A samples from both species of bacteria. Additionally, we found an approximately 10-fold increase in the level of AraN in lipid A isolated from Salmonella grown in magnesium-limited versus magnesium-replete conditions. Salmonella with defined mutations in lipid A synthesis and regulatory genes were used to further validate the assay. Salmonella with null mutations in the phoP, pmrE, and prmF genes were unable to add AraN to their lipid A, while Salmonella with constitutively active phoP and pmrA exhibited AraN modification of lipid A even in the normally repressive magnesium-replete growth condition. The described assay produces excellent repeatability and reproducibility for the detection of amino-containing moieties in lipid A from a variety of bacterial sources. PMID:19130491

  5. Toxicity evaluation of selected ammonium-based ionic liquid forms with MCPP and dicamba moieties on Pseudomonas putida.

    PubMed

    Piotrowska, Aleksandra; Syguda, Anna; Wyrwas, Bogdan; Chrzanowski, Łukasz; Heipieper, Hermann J

    2017-01-01

    Combination of the hydrophilic herbicidal anion with hydrophobic, antimicrobial ammonium cation allows to obtain compounds in ionic liquid form with better properties then conventional herbicides. Both cation and anion can be modified by selection of herbicide and the length of alkyl chains in cation structure. However the knowledge of their potential toxic effects are still limited. Furthermore, the relation between hydrophobicity associated with the length of alkyl chains and toxicity for ionic liquids has not been thoroughly studied. Therefore we investigated toxic effects of herbicidal ionic liquid forms on growth inhibition, given as EC50, of the common soil bacterium Pseudomonas putida. We thereby concentrated on quaternary ammonium salts. Analyzed compounds were composed of dicamba or MCPP moieties and cation with various alkyl chain lengths (n = 6,8,10) We compared them with commercial herbicides, and ammonium-based ionic liquids with neutral anion (Br(-)). In addition, cis-trans isomerisation of unsaturated membrane fatty acids in Pseudomonas putida was applied as the proxy for toxicity and membrane activity. We showed that toxicity increased with the length of alkyl chains. However, this correlation is only valid for six and eight carbon atom in alkyl chains, where for n = 10 the EC50 values rise by one order of magnitude. In our studies, the herbicidal ionic liquids [C10,C10,C1,C1N][MCPP] and [C10,C10,C1,C1N][dicamba] showed the lowest toxicity among analyzed quaternary ammonium salts and comparable toxicity with corresponding herbicides. No clear increase in toxicity could be followed by changing the anion moieties for ammonium-based ionic liquid forms.

  6. Reactive attachment disorder--a theoretical model beyond attachment.

    PubMed

    Minnis, Helen; Marwick, Helen; Arthur, Julie; McLaughlin, Alexis

    2006-09-01

    Despite its importance in public health, reactive attachment disorder (RAD) is an under-researched and little used clinical category. Abnormalities of social relatedness have long been documented in children who have been abused, neglected or institutionalised, but there have been more recent efforts to define these behaviours within the psychiatric nosology. There has been an implicit assumption that the central deficit in RAD is in the attachment system, but this has caused controversy and may have blocked research. We propose that RAD is better construed within the framework of intersubjectivity, which has a central role in the development of core brain and social functions and may also have had an important role in the evolution of a key human characteristic-complex social functioning. This broader framework may potentially explain apparently diverse symptoms such as indiscriminate friendliness and negative or unpredictable reunion responses. Finally, we suggest that a change of name may be useful in progressing the field, but accept that this may be difficult until there is better agreement in the clinical and scientific communities about the core features and aetiology of this disorder.

  7. Split ring containment attachment device

    DOEpatents

    Sammel, Alfred G.

    1996-01-01

    A containment attachment device 10 for operatively connecting a glovebag 200 to plastic sheeting 100 covering hazardous material. The device 10 includes an inner split ring member 20 connected on one end 22 to a middle ring member 30 wherein the free end 21 of the split ring member 20 is inserted through a slit 101 in the plastic sheeting 100 to captively engage a generally circular portion of the plastic sheeting 100. A collar potion 41 having an outer ring portion 42 is provided with fastening means 51 for securing the device 10 together wherein the glovebag 200 is operatively connected to the collar portion 41.

  8. Preferred Attachment in Affiliation Networks

    NASA Astrophysics Data System (ADS)

    Bloznelis, Mindaugas; Götze, Friedrich

    2014-08-01

    Vertices of an affiliation network are linked to attributes and two vertices are declared adjacent whenever they share a common attribute. For example, two customers of an internet shop (or video-sharing website) are called adjacent if they have purchased (or downloaded) the same or similar items. Assuming that each newly arrived customer is linked preferentially to already popular items we obtain a preferred attachment affiliation network that evolves in time. We show that the fraction of customers having neighbours scales as for large . Here is the ratio between the two intensities: intensity of the flow of customers and that of the newly arriving items.

  9. Domino syntheses of bioactive tetronic and tetramic acids

    NASA Astrophysics Data System (ADS)

    Schobert, Rainer

    2007-01-01

    Natural products containing tetronic acid or tetramic acid moieties continue to attract the interest of chemists, biologists, and physicians due to their challenging structures and to the wide range of biological activities they display. This review portrays the structural varieties of tetronic and tetramic acids and the spectrum of possible therapeutically relevant effects in man for exemplary derivatives. Their biosynthetic origin from α-amino and α-hydroxy acids is briefly discussed as is the relationship between their structures and their modes of interaction with biochemical effectors such as metal cations or enzymes. A short overview of laboratory syntheses of the heterocyclic core structures of tetramic and tetronic acids is provided with an emphasis on those emulating the biosynthesis. A synthesis from the α-amino or α-hydroxy esters and the cumulated phosphorus ylide Ph3PCCO based upon a domino addition-intra-Wittig alkenation sequence is presented with applications to the preparation of the antibiotics reutericyclin and tenuazonic acid, the cytotoxic melophlin B, and the enzyme inhibitor RK-682. Procedural advantages of immobilizing either starting component by attaching it to a resin and its exploitation in the parallel synthesis of libraries of potential drug candidates are described. The basic domino reaction can even be extended by further C-C bond forming steps when starting from suitable α-hydroxy or α-amino allyl esters. Depending on the chosen reaction conditions, bioactive intermediates of formally three to seven step long cascades can be obtained. Among them, herbicidal 3-alkyltetronic acids and lactone endoperoxides with antiplasmodial activity exceeding that of the natural antimalarial lead artemisinin. Hence, this domino reaction gives access to diversely functionalized derivatives of tetronic and tetramic acids. As it can also be ported to solid phase, it is ideally suited for parallel and combinatorial processing. Future developments

  10. Chicoric acid analogues as HIV-1 integrase inhibitors.

    PubMed

    Lin, Z; Neamati, N; Zhao, H; Kiryu, Y; Turpin, J A; Aberham, C; Strebel, K; Kohn, K; Witvrouw, M; Pannecouque, C; Debyser, Z; De Clercq, E; Rice, W G; Pommier, Y; Burke, T R

    1999-04-22

    The present study was undertaken to examine structural features of L-chicoric acid (3) which are important for potency against purified HIV-1 integrase and for reported cytoprotective effects in cell-based systems. Through a progressive series of analogues, it was shown that enantiomeric D-chicoric acid (4) retains inhibitory potency against purified integrase equal to its L-counterpart and further that removal of either one or both carboxylic functionalities results in essentially no loss of inhibitory potency. Additionally, while two caffeoyl moieties are required, attachment of caffeoyl groups to the central linking structure can be achieved via amide or mixed amide/ester linkages. More remarkable is the finding that blockage of the catechol functionality through conversion to tetraacetate esters results in almost no loss of potency, contingent on the presence of at least one carboxyl group on the central linker. Taken as a whole, the work has resulted in the identification of new integrase inhibitors which may be regarded as bis-caffeoyl derivatives of glycidic acid and amino acids such as serine and beta-aminoalanine. The present study also examined the reported ability of chicoric acid to exert cytoprotective effects in HIV-infected cells. It was demonstrated in target and cell-based assays that the chicoric acids do not significantly inhibit other targets associated with HIV-1 replication, including reverse transcription, protease function, NCp7 zinc finger function, or replication of virus from latently infected cells. In CEM cells, for both the parent chicoric acid and selected analogues, antiviral activity was observable under specific assay conditions and with high dependence on the multiplicity of viral infection. However, against HIV-1- and HIV-2-infected MT-4 cells, the chicoric acids and their tetraacetylated esters exhibited antiviral activity (50% effective concentration (EC50) ranging from 1.7 to 20 microM and 50% inhibitory concentration (IC50

  11. Conjugation of Methotrexate-Amino Derivatives to Macromolecules through Carboxylate Moieties Is Superior Over Conventional Linkage to Amino Residues: Chemical, Cell-Free and In Vitro Characterizations

    PubMed Central

    Cooper, Itzik; Fridkin, Mati; Shechter, Yoram

    2016-01-01

    In this study, we examined the possibility of introducing methotrexate (MTX) to the carboxylate rather than to the ε-amino side chains of proteins. We found that MTX—amino compounds covalently linked to the carboxylate moieties of macromolecules, undergo unusual peptide-bond cleavage, with the release of the MTX amino derivatives from the conjugates. This event takes place at an accelerated rate under acidic conditions, and at a slower rate at physiological pH values. The glutamate portion of MTX is responsible for this behavior, with little or no contribution of the p-aminobenzoate-pteridine ring that is linked to the α-amino side chain of the glutamate. Carboxylate-linked Fmoc-Glu-γ-CONH-(CH2)6-NH2 undergoes hydrolysis in a nearly indistinguishable fashion. A free α carboxylate moiety is essential for this effect. Carboxylate linked Fmoc-glutamic-amide-γ-CONH-(CH2)6-NH2 undergoes no hydrolysis under acidic conditions. Based on these findings, we engineered a cysteine specific MTX containing reagent. Its linkage to bovine serum albumin (BSA) yielded a conjugate with profound antiproliferative efficacy in a MTX-sensitive glioma cell line. In conclusion, carboxylate linked MTX-amino derivatives in particular, and carboxylate linked R-α-GLU-γ amino compounds in general are equipped with‘built-in chemical machinery’ that releases them under mild acidic conditions. PMID:27403959

  12. Amino acid sequence of a mouse immunoglobulin mu chain.

    PubMed Central

    Kehry, M; Sibley, C; Fuhrman, J; Schilling, J; Hood, L E

    1979-01-01

    The complete amino acid sequence of the mouse mu chain from the BALB/c myeloma tumor MOPC 104E is reported. The C mu region contains four consecutive homology regions of approximately 110 residues and a COOH-terminal region of 19 residues. A comparison of this mu chain from mouse with a complete mu sequence from human (Ou) and a partial mu chain sequence from dog (Moo) reveals a striking gradient of increasing homology from the NH2-terminal to the COOH-terminal portion of these mu chains, with the former being the least and the latter the most highly conserved. Four of the five sites of carbohydrate attachment appear to be at identical residue positions when the constant regions of the mouse and human mu chains are compared. The mu chain of MOPC 104E has a carbohydrate moiety attached in the second hypervariable region. This is particularly interesting in view of the fact that MOPC 104E binds alpha-(1 leads to 3)-dextran, a simple carbohydrate. The structural and functional constraints imposed by these comparative sequence analyses are discussed. PMID:111247

  13. CHARMM force field parameterization protocol for self-assembling peptide amphiphiles: the Fmoc moiety.

    PubMed

    Ramos Sasselli, I; Ulijn, R V; Tuttle, T

    2016-02-14

    Aromatic peptide amphiphiles are known to self-assemble into nanostructures but the molecular level structure and the mechanism of formation of these nanostructures is not yet understood in detail. Molecular dynamic simulations using the CHARMM force field have been applied to a wide variety of peptide-based systems to obtain molecular level details of processes that are inaccessible with experimental techniques. However, this force field does not include parameters for the aromatic moieties which dictate the self-assembly of these systems. The standard CHARMM force field parameterization protocol uses hydrophilic interactions for the non-bonding parameters evaluation. However, to effectively reproduce the self-assembling behaviour of these molecules, the balance between the hydrophilic and hydrophobic nature of the molecule is essential. In this work, a modified parameterization protocol for the CHARMM force field for these aromatic moieties is presented. This protocol is applied for the specific case of the Fmoc moiety. The resulting set of parameters satisfies the conformational and interactions analysis and is able to reproduce experimental results such as the Fmoc-S-OMe water/octanol partition free energy and the self-assembly of Fmoc-S-OH and Fmoc-Y-OH into spherical micelles and fibres, respectively, while also providing detailed information on the mechanism of these processes. The effectiveness of the parameters for the Fmoc moiety validates the protocol as a robust approach to paramterise this class of compounds.

  14. Arsenic moiety in gallium arsenide is responsible for neuronal apoptosis and behavioral alterations in rats.

    PubMed

    Flora, Swaran J S; Bhatt, Kapil; Mehta, Ashish

    2009-10-15

    Gallium arsenide (GaAs), an intermetallic semiconductor finds widespread applications in high frequency microwave and millimeter wave, and ultra fast supercomputers. Extensive use of GaAs has led to increased exposure to humans working in semiconductor industry. GaAs has the ability to dissociate into its constitutive moieties at physiological pH and might be responsible for the oxidative stress. The present study was aimed at evaluating, the principle moiety (Ga or As) in GaAs to cause neurological dysfunction based on its ability to cause apoptosis, in vivo and in vitro and if this neuronal dysfunction translated to neurobehavioral changes in chronically exposed rats. Result indicated that arsenic moiety in GaAs was mainly responsible for causing oxidative stress via increased reactive oxygen species (ROS) and nitric oxide (NO) generation, both in vitro and in vivo. Increased ROS further caused apoptosis via mitochondrial driven pathway. Effects of oxidative stress were also confirmed based on alterations in antioxidant enzymes, GPx, GST and SOD in rat brain. We noted that ROS induced oxidative stress caused changes in the brain neurotransmitter levels, Acetylcholinesterase and nitric oxide synthase, leading to loss of memory and learning in rats. The study demonstrates for the first time that the slow release of arsenic moiety from GaAs is mainly responsible for oxidative stress induced apoptosis in neuronal cells causing behavioral changes.

  15. Anion-directed self-organization of thermotropic liquid crystalline materials containing a guanidinium moiety.

    PubMed

    Kim, Dongwoo; Jon, Sangyong; Lee, Hyung-Kun; Baek, Kangkyun; Oh, Nam-Keun; Zin, Wang-Cheol; Kim, Kimoon

    2005-11-28

    New wedge-shaped thermotropic liquid crystalline materials containing a guanidinium moiety at the apex organize into various supramolecular structures such as hexagonal columnar, rectangular columnar and Pm3n cubic mesophases depending on anions illustrating guest-directed self-organization in mesophases.

  16. Arsenic moiety in gallium arsenide is responsible for neuronal apoptosis and behavioral alterations in rats

    SciTech Connect

    Flora, Swaran J.S. Bhatt, Kapil; Mehta, Ashish

    2009-10-15

    Gallium arsenide (GaAs), an intermetallic semiconductor finds widespread applications in high frequency microwave and millimeter wave, and ultra fast supercomputers. Extensive use of GaAs has led to increased exposure to humans working in semiconductor industry. GaAs has the ability to dissociate into its constitutive moieties at physiological pH and might be responsible for the oxidative stress. The present study was aimed at evaluating, the principle moiety (Ga or As) in GaAs to cause neurological dysfunction based on its ability to cause apoptosis, in vivo and in vitro and if this neuronal dysfunction translated to neurobehavioral changes in chronically exposed rats. Result indicated that arsenic moiety in GaAs was mainly responsible for causing oxidative stress via increased reactive oxygen species (ROS) and nitric oxide (NO) generation, both in vitro and in vivo. Increased ROS further caused apoptosis via mitochondrial driven pathway. Effects of oxidative stress were also confirmed based on alterations in antioxidant enzymes, GPx, GST and SOD in rat brain. We noted that ROS induced oxidative stress caused changes in the brain neurotransmitter levels, Acetylcholinesterase and nitric oxide synthase, leading to loss of memory and learning in rats. The study demonstrates for the first time that the slow release of arsenic moiety from GaAs is mainly responsible for oxidative stress induced apoptosis in neuronal cells causing behavioral changes.

  17. Fluoride-induced modulation of ionic transport in asymmetric nanopores functionalized with ``caged'' fluorescein moieties

    NASA Astrophysics Data System (ADS)

    Ali, Mubarak; Ahmed, Ishtiaq; Ramirez, Patricio; Nasir, Saima; Cervera, Javier; Niemeyer, Christof M.; Ensinger, Wolfgang

    2016-04-01

    We demonstrate experimentally and theoretically a nanofluidic fluoride sensing device based on a single conical pore functionalized with ``caged'' fluorescein moieties. The nanopore functionalization is based on an amine-terminated fluorescein whose phenolic hydroxyl groups are protected with tert-butyldiphenylsilyl (TBDPS) moieties. The protected fluorescein (Fcn-TBDPS-NH2) molecules are then immobilized on the nanopore surface via carbodiimide coupling chemistry. Exposure to fluoride ions removes the uncharged TBDPS moieties due to the fluoride-promoted cleavage of the silicon-oxygen bond, leading to the generation of negatively charged groups on the fluorescein moieties immobilized onto the pore surface. The asymmetrical distribution of these groups along the conical nanopore leads to the electrical rectification observed in the current-voltage (I-V) curve. On the contrary, other halides and anions are not able to induce any significant ionic rectification in the asymmetric pore. In each case, the success of the chemical functionalization and deprotection reactions is monitored through the changes observed in the I-V curves before and after the specified reaction step. The theoretical results based on the Nernst-Planck and Poisson equations further demonstrate the validity of an experimental approach to fluoride-induced modulation of nanopore current rectification behaviour.

  18. Can a Non-Chiral Object Be Made of Two Identical Chiral Moieties?

    ERIC Educational Resources Information Center

    LeMarechal, Jean Francois

    2008-01-01

    Several pedagogical objects can be used to discuss chirality. Here, we use the cut of an apple to show that the association of identical chiral moieties can form a non-chiral object. Octahedral chirality is used to find situations equivalent to the cut of the apple. (Contains 5 figures.)

  19. The viability of aluminum Zintl anion moieties within magnesium-aluminum clusters

    SciTech Connect

    Wang, Haopeng; Jae Ko, Yeon; Zhang, Xinxing; Gantefoer, Gerd; Bowen, Kit H. E-mail: akandalam@wcupa.edu; Schnoeckel, Hansgeorg; Eichhorn, Bryan W.; Jena, Puru; Kiran, Boggavarapu E-mail: akandalam@wcupa.edu; Kandalam, Anil K. E-mail: akandalam@wcupa.edu

    2014-03-28

    Through a synergetic combination of anion photoelectron spectroscopy and density functional theory based calculations, we have investigated the extent to which the aluminum moieties within selected magnesium-aluminum clusters are Zintl anions. Magnesium-aluminum cluster anions were generated in a pulsed arc discharge source. After mass selection, photoelectron spectra of Mg{sub m}Al{sub n}{sup −} (m, n = 1,6; 2,5; 2,12; and 3,11) were measured by a magnetic bottle, electron energy analyzer. Calculations on these four stoichiometries provided geometric structures and full charge analyses for the cluster anions and their neutral cluster counterparts, as well as photodetachment transition energies (stick spectra). Calculations revealed that, unlike the cases of recently reported sodium-aluminum clusters, the formation of aluminum Zintl anion moieties within magnesium-aluminum clusters was limited in most cases by weak charge transfer between the magnesium atoms and their aluminum cluster moieties. Only in cases of high magnesium content, e.g., in Mg{sub 3}Al{sub 11} and Mg{sub 2}Al{sub 12}{sup −}, did the aluminum moieties exhibit Zintl anion-like characteristics.

  20. Thiamin biosynthesis in Saccharomyces cerevisiae. Origin of carbon-2 of the thiazole moiety.

    PubMed Central

    White, R L; Spenser, I D

    1979-01-01

    Radioactivity from [2-14C]glycine enters C-2 of the thiazole moiety of thiamin and no other site, in Saccharomyces cerevisiae (strains A.T.C.C. 24903 and 39916, H.J. Bunker). Radioactivity from L-[Me-14C]methionine or from DL-[2-14C]tyrosine does not enter thiamin. PMID:384994

  1. Methane production by attached film

    DOEpatents

    Jewell, William J.

    1981-01-01

    A method for purifying wastewater of biodegradable organics by converting the organics to methane and carbon dioxide gases is disclosed, characterized by the use of an anaerobic attached film expanded bed reactor for the reaction process. Dilute organic waste material is initially seeded with a heterogeneous anaerobic bacteria population including a methane-producing bacteria. The seeded organic waste material is introduced into the bottom of the expanded bed reactor which includes a particulate support media coated with a polysaccharide film. A low-velocity upward flow of the organic waste material is established through the bed during which the attached bacterial film reacts with the organic material to produce methane and carbon dioxide gases, purified water, and a small amount of residual effluent material. The residual effluent material is filtered by the film as it flows upwardly through the reactor bed. In a preferred embodiment, partially treated effluent material is recycled from the top of the bed to the bottom of the bed for further treatment. The methane and carbon dioxide gases are then separated from the residual effluent material and purified water.

  2. Attachment and borderline personality disorder.

    PubMed

    Fonagy, P

    2000-01-01

    The author outlines his concept of reflective function or mentalization, which is defined as the capacity to think about mental states in oneself and in others. He presents evidence to suggest that the capacity for reflective awareness in a child's caregiver increases the likelihood of the child's secure attachment, which in turn facilitates the development of mentalization in the child. He proposes that a secure attachment relationship offers the child a chance to explore the mind of the caregiver, and in this way to learn about minds; he formulates this model of the birth of the psychological self as a variation on the Cartesian cogito: "My caregiver thinks of me as thinking and therefore I exist as a thinker." This model is then applied to provide insight into some personality-disordered individuals who were victims of childhood abuse. The author proposes (1) that individuals who experience early trauma may defensively inhibit their capacity to mentalize to avoid having to think about their caregiver's wish to harm them; and (2) that some characteristics of severe borderline personality disorder may be rooted in developmental pathology associated with this inhibition. He offers evidence for and some qualifications of this model, and argues that the therapeutic effect of psychoanalysis depends on its capacity to activate patients' ability to evolve an awareness of mental states and thus find meaning in their own and other people's behavior.

  3. Attachment in romantic relationships and somatization.

    PubMed

    Neumann, Eva; Sattel, Heribert; Gündel, Harald; Henningsen, Peter; Kruse, Johannes

    2015-02-01

    Adult attachment representations have been considered to play a role in the development and treatment of somatizing behavior. In this study, the associations between the two attachment dimensions avoidance and anxiety and dimensions of psychopathology (somatization, depression, and general anxiety) were explored. The sample consists of 202 outpatients diagnosed with a somatoform disorder. Data were collected via self-report measures. A path analysis shows that the two attachment dimensions are not directly associated with somatization. There are, however, significant indirect associations between attachment and somatization mediated by depression and general anxiety, which are more pronounced for attachment anxiety than for attachment avoidance. The findings reveal that a low level of attachment security in romantic relationships, especially an anxious stance toward the partner, comes along with poor mental health, which in turn is related to a preoccupation with somatic complaints. Implications for the treatment of somatizing patients are discussed.

  4. Attachment relationship experiences and childhood psychopathology.

    PubMed

    Zeanah, Charles H; Keyes, Angela; Settles, Lisa

    2003-12-01

    Human infants form attachments to their caregivers gradually over the course of the first year of life. Qualitatively different types of attachments, which can be identified by the end of the first year, are broadly predictive of subsequent adaptive outcomes for young children. "Disorganized" patterns of attachment have the strongest links to concurrent and subsequent psychopathology, and considerable research has demonstrated both within-the-child and environmental correlates of disorganized attachment. Clinical disorders of attachment have been demonstrated to arise under conditions of social deprivation, such as institutionalization and maltreatment. An emotionally withdrawn/inhibited pattern and an indiscriminate/disinhibited pattern both have been described. Although these clinical types arise under similar conditions of environmental adversity, they tend to have different courses over time. We describe recent findings and highlight areas of emerging consensus and areas of continuing controversy regarding both disorganized patterns of attachment and clinical disorders of attachment in young children.

  5. Preparation, spectral and biological investigation of formaldehyde-based ligand containing piperazine moiety and its various polymer metal complexes

    NASA Astrophysics Data System (ADS)

    Khan, Shamim Ahmad; Nishat, Nahid; Parveen, Shadma; Rasool, Raza

    2011-10-01

    A novel tetradentate salicylic acid-formaldehyde ligand containing piperazine moiety (SFP) was synthesized by condensation of salicylic acid, formaldehyde and piperazine in presence of base catalyst, which was subjected for the preparation of coordination polymers with metal ions like manganese(II), cobalt(II), copper(II), nickel(II) and zinc(II). All the synthesized polymeric compounds were characterized by elemental analysis, IR, 1H NMR and electronic spectral studies. The thermal stability was determined by thermogravimetric analysis and thermal data revealed that all the polymer metal complexes show good thermal stability than their parent ligand. Electronic spectral data and magnetic moment values revealed that polymer metal complexes of Mn(II), Co(II) and Ni(II) show an octahedral geometry while Cu(II) and Zn(II) show distorted octahedral and tetrahedral geometry respectively. The antimicrobial screening of the ligand and coordination polymers was done by using Agar well diffusion method against various bacteria and fungi. It was evident from the data that antibacterial and antifungal activity increased on chelation and all the polymer metal complexes show excellent antimicrobial activity than their parent ligand.

  6. Neuraminidase Receptor Binding Variants of Human Influenza A(H3N2) Viruses Resulting from Substitution of Aspartic Acid 151 in the Catalytic Site: a Role in Virus Attachment?▿

    PubMed Central

    Lin, Yi Pu; Gregory, Victoria; Collins, Patrick; Kloess, Johannes; Wharton, Stephen; Cattle, Nicholas; Lackenby, Angie; Daniels, Rodney; Hay, Alan

    2010-01-01

    Changes in the receptor binding characteristics of human H3N2 viruses have been evident from changes in the agglutination of different red blood cells (RBCs) and the reduced growth capacity of recently isolated viruses, particularly in embryonated eggs. An additional peculiarity of viruses circulating in 2005 to 2009 has been the poor inhibition of hemagglutination by postinfection ferret antisera for many viruses isolated in MDCK cells, including homologous reference viruses. This was shown not to be due to an antigenic change in hemagglutinin (HA) but was shown to be the result of a mutation in aspartic acid 151 of neuraminidase (NA) to glycine, asparagine, or alanine, which caused an oseltamivir-sensitive agglutination of RBCs. The D151G substitution was shown to cause a change in the specificity of NA such that it acquired the capacity to bind receptors, which were refractory to enzymatic cleavage, without altering its ability to remove receptors for HA. Thus, the inhibition of NA-dependent agglutination by the inclusion of oseltamivir carboxylate in the assay was effective in restoring the anti-HA specificity of the hemagglutination inhibition (HI) assay for monitoring antigenic changes in HA. Since the NA-dependent binding activity did not affect virus neutralization, and virus populations in clinical specimens possessed, at most, low levels of the “151 mutant,” the biological significance of this feature of NA in, for example, immune evasion is unclear. It is apparent, however, that an important role of aspartic acid 151 in the activity of NA may be to restrict the specificity of the NA interaction and its receptor-destroying activity to complement that of HA receptor binding. PMID:20410266

  7. A Scanning Electron Microscopic Study of Cell Attachment to Biodegradable Polymer Implants

    DTIC Science & Technology

    1988-08-15

    attachment ABSTRACT Y he biodegradable polymers, polylactic acid (PLA) and polyglycolic acid (PGA) are currently being studied as carriers for bioactive bone ...Research focuses on their use for sustained antibiotic delivery, bone fracture stabilization, moldable osseous repair materials and as vehicles for...hydrolytic scission which may be mediated by a variety of proteolytic enzymes. (1 ,7) Through this process, both lactic acid and glycolic acid , the respective

  8. Synthesis and evaluation of water-soluble prodrugs of ursodeoxycholic acid (UDCA), an anti-apoptotic bile acid.

    PubMed

    Dosa, Peter I; Ward, Tim; Castro, Rui E; Rodrigues, Cecília M P; Steer, Clifford J

    2013-06-01

    Ursodeoxycholic acid (UDCA) is a bile acid with demonstrated anti-apoptotic activity in both in vitro and in vivo models. However, its utility is hampered by limited aqueous solubility. As such, water-soluble prodrugs of UDCA could have an advantage over the parent bile acid in indications where intravenous administration might be preferable, such as decreasing damage from stroke or acute kidney injury. Five phosphate prodrugs were synthesized, including one incorporating a novel phosphoryloxymethyl carboxylate (POMC) moiety. These prodrugs were highly water-soluble, but showed significant differences in chemical stability, with oxymethylphosphate prodrugs being the most unstable. In a series of NMR experiments, the POMC prodrug was bioactivated to UDCA by alkaline phosphatase (AP) faster than a prodrug containing a phosphate directly attached to the alcohol at the 3-position of UDCA. Both of these prodrugs showed significant anti-apoptotic activity in a series of in vitro assays, although the POMC prodrug required the addition of AP for activity, while the other compound was active without exogenous AP.

  9. Dissociative Electron Attachment to chloroacetylene

    NASA Astrophysics Data System (ADS)

    Ngassam, V.; Orel, A. E.

    2007-06-01

    The production of two fragments with σ symmetry from electron-impact dissociation of C2H2, which has only a low lying &*circ; resonance at equilibrium geometry, has been explained by the existence of interactions with &*circ; resonances at bent geometries. We are investigating the presence of such multidimensional effects in the dissociative attachment of chloroacetylene (C2HCl). We have performed electron scattering calculations using the Complex Kohn variational method to determine the resonance energies and widths of the chloroacetylene resonances as a function of both the Cl--C2H bond distance as well as the variation with C-C stretch and bend. We will discuss our results and our prediction of the dissociation dynamics in comparison to the findings for for C2H2. This work was supported by the U.S. DOE Office of Basic Energy Sciences, Division of Chemical Sciences and the National Science Foundation, PHY-05-55401.

  10. Hydrophobic metabolites of 2,4-dichlorophenoxyacetic acid (2,4-D) in cultured coconut tissue.

    PubMed

    López-Villalobos, Arturo; Hornung, Roland; Dodds, Peter F

    2004-10-01

    Cultures of inflorescence and plumular tissues of coconut palm (Cocos nucifera L.) were maintained in the presence of the auxin, [14C]2,4-dichlorophenoxyacetic acid (2,4-D), so that its metabolic fate could be studied. Thin layer chromatography of methanol extracts of the plumular tissue showed that four classes of metabolites, as well as the unchanged acid, were recovered in the extract. In inflorescence tissue, only the unchanged acid and the most polar class of metabolites (metabolite I) were recovered. Metabolite I was shown to consist mostly of a mixture of sugar conjugates and metabolite II (the next most polar) was an unidentified basic metabolite. Metabolites III and IV were both novel triacylglycerol analogues in which one of the natural fatty acids was replaced with a chain-elongated form of 2,4-D. Reversed-phase thin layer chromatography was used to identify the 2,4-D-derived acids and it was found that metabolite III contained the 2,4-dichlorophenoxy-moiety attached to a chain-length of between 2 and 12 carbons, whereas metabolite IV contained 12, 14 and 16 carbon chain lengths. In inflorescence tissue, and in plumular tissue at low sucrose or 2,4-D concentrations and after short periods in culture, metabolite I predominated. The other metabolites increased as a percentage when plumular culture was prolonged or when sucrose or 2,4-D concentrations were raised. These changes correlated with better development of the explant.

  11. Place attachment and disasters: Knowns and unknowns.

    PubMed

    Jamali, Mehdi; Nejat, Ali

    When considering the factors important for disaster recovery, one must consider the attachment individuals have toward their living area. This article reviews and synthesizes the current literature on the determinants of place attachment in the context of postdisaster recovery. Although the majority of the reviewed articles focused on disaster recovery, there were some which had a broader scope and were included due to their importance. This research categorizes the determinants of place attachment into four categories: demographic, socioeconomic, spatial, and psychosocial. Age, ethnicity, and religion were grouped under the category of demographics. Job status, education, and property ownership were categorized under the socioeconomic category. Attachment to home, neighborhood, and city, together with attachment to rural and urban areas, were grouped under the spatial category. Finally, mental health status and community attachment were classified under the psychosocial heading. Based on the outcome of the aforementioned synthesis, this article develops a conceptual framework to guide future research.

  12. [Attachment representation of adolescents in residential care].

    PubMed

    Schleiffer, Roland; Müller, Susanne

    2002-12-01

    In this investigation the attachment representations of adolescents in residential care were examined for the first time. 72 adolescents were interviewed by using the Adult Attachment Interview (AAI). At the same time the degree of adolescent psychopathology was recorded. For this purpose the caregivers completed Achenbach's Child Behavior Checklist (CBCL), the adolescents themselves answered Achenbach's Youth Self Report (YSR). The adolescents in this sample proved to be severely burdened in psychopathological terms. They had access to only an insecure and, in many cases, an extremely insecure attachment representation. For a sub-group of adolescent mothers the early infant-mother attachment was examined using Ainsworth's Strange Situation. The findings show an intergenerational transmission of insecure attachment relationships. The implications of these results for the practice of residential care inspired by attachment theory are discussed.

  13. Investigation of electron attachment in polyatomic molecules

    NASA Astrophysics Data System (ADS)

    Dowell, J. T.

    1980-05-01

    Electron attachment to polyatomic molecules was studied using molecular beams of variable temperature crossed with an electron of high energy resolution. Species investigated include sulfur hexafluoride, molybdenum hexafluoride, and tungsten oxide polymers. New results were obtained in sulfur hexafluoride demonstrating importance of internal energy for the dissociative attachment in molybdenum hexafluoride. Tungsten oxide vapor exhibits both monomer and dimer negative ion formation near zero energy, apparently from dissociative attachment to the trimer.

  14. Attachment processes in eating disorder and depression.

    PubMed

    Cole-Detke, H; Kobak, R

    1996-04-01

    This study examines the relationship between attachment strategies and symptom reporting among college women. Sixty-one college women were selected who reported high or low levels of depressive and eating disorder symptoms. The Adult Attachment Interview (AAI) was administered, and interview transcripts were rated with the Attachment Interview Q-Sort. The results indicated that women with hyperactivating AAI strategies were prone to reporting elevated levels of depressive symptoms, whereas women with deactivating strategies were prone to reporting elevated levels of eating-disorder symptoms, when depression was statistically controlled. These findings support the hypothesis that secondary or defensive attachment strategies predispose individuals toward different forms of symptom expression.

  15. Sine-Bar Attachment For Machine Tools

    NASA Technical Reports Server (NTRS)

    Mann, Franklin D.

    1988-01-01

    Sine-bar attachment for collets, spindles, and chucks helps machinists set up quickly for precise angular cuts that require greater precision than provided by graduations of machine tools. Machinist uses attachment to index head, carriage of milling machine or lathe relative to table or turning axis of tool. Attachment accurate to 1 minute or arc depending on length of sine bar and precision of gauge blocks in setup. Attachment installs quickly and easily on almost any type of lathe or mill. Requires no special clamps or fixtures, and eliminates many trial-and-error measurements. More stable than improvised setups and not jarred out of position readily.

  16. Influence of the galloyl moiety in tea catechins on binding affinity for human serum albumin.

    PubMed

    Minoda, Kanako; Ichikawa, Tatsuya; Katsumata, Tomoharu; Onobori, Ken-ichi; Mori, Taiki; Suzuki, Yukiko; Ishii, Takeshi; Nakayama, Tsutomu

    2010-01-01

    The major catechins of green tea extract are (-)-epicatechin (EC), (-)-epigallocatechin (EGC), (-)-epicatechin gallate (ECg), and (-)-epigallocatechin gallate (EGCg). Recent research has indicated that catechins form complexes with human serum albumin (HSA) in blood, and differences in their binding affinity toward HSA are believed to modulate their bioavailability. In this study, we kinetically investigated the interaction between the catechins and HSA immobilized on a quartz-crystal microbalance (QCM). The association constants obtained from the frequency changes of QCM revealed interactions of ECg and EGCg with HSA that are 100 times stronger than those of EC and EGC. Furthermore, comparisons of these catechins by native-gel electrophoresis/blotting with redox-cycling staining revealed that, in a phosphate buffer, ECg and EGCg have a higher binding affinity toward HSA than EC and EGC. These observations indicate that catechins with a galloyl moiety have higher binding affinities toward HSA than catechins lacking a galloyl moiety.

  17. Novel hydrazone derivatives containing pyridine amide moiety: Design, synthesis, and insecticidal activity.

    PubMed

    Yang, Zai-Bo; Hu, De-Yu; Zeng, Song; Song, Bao-An

    2016-02-15

    A series of novel hydrazone derivatives containing pyridine amide moiety were designed, synthesized, and evaluated for their insecticidal activity. Bioassays indicated that some of the target compounds exhibited good insecticidal activities against Nilaparvata lugens (N. lugens), Plutella xylostella (P. xylostella), Mythimna separata (M. separata), Helicoverpa armigera (H. armigera), Pyrausta nubilalis (P. nubilalis), and Culex pipiens pallens (C. pipiens pallens). In particular, compound 5j revealed excellent insecticidal activity against C. pipiens pallens, with the 50% lethal concentration (LC50) and the 95% lethal concentration (LC95) values of 2.44 and 5.76 mg/L, respectively, which were similar to those of chlorpyrifos (3.26 and 6.98 mg/L, respectively), tebufenozide (1.22 and 2.49 mg/L, respectively), and RH-5849 (2.61 and 6.37 mg/L, respectively). These results indicated that hydrazone derivatives containing pyridine amide moiety could be developed as novel and promising insecticides.

  18. Immobilization of invertase through its carbohydrate moiety on Ocimum basilicum seed.

    PubMed

    Melo, J S; D'Souza, S F

    1992-01-01

    Yeast invertase, a glycoprotein, was covalently coupled to Ocimum basilicum seeds either through its protein or carbohydrate moiety. Of the various methods investigated, binding of the enzyme through its carbohydrate moiety resulted in the retention of considerably higher amounts of enzyme activity. Immobilized invertase showed a shift in the pH optimum toward the alkaline side without appreciable change in temperature optimum. However, the immobilized preparation was more thermostable than the free enzyme. Invertase bound to the seeds could be used repeatedly for the hydrolysis of sucrose syrups in a batch process without appreciable loss in activity. The seeds could serve as an inexpensive, ready-to-use, natural pellicular polysaccharide support for immobilizing enzymes.

  19. Decisive Interactions between the Heterocyclic Moiety and the Cluster Observed in Polyoxometalate-Surfactant Hybrid Crystals

    PubMed Central

    Otobe, Saki; Fujioka, Natsumi; Hirano, Takuro; Ishikawa, Eri; Naruke, Haruo; Fujio, Katsuhiko; Ito, Takeru

    2015-01-01

    Inorganic-organic hybrid crystals were successfully obtained as single crystals by using polyoxotungstate anion and cationic dodecylpyridazinium (C12pda) and dodecylpyridinium (C12py) surfactants. The decatungstate (W10) anion was used as the inorganic component, and the crystal structures were compared. In the crystal comprising C12pda (C12pda-W10), the heterocyclic moiety directly interacted with W10, which contributed to a build-up of the crystal structure. On the other hand, the crystal consisting of C12py (C12py-W10) had similar crystal packing and molecular arrangement to those in the W10 crystal hybridized with other pyridinium surfactants. These results indicate the significance of the heterocyclic moiety of the surfactant to construct hybrid crystals with polyoxometalate anions. PMID:25894221

  20. New biocide with both N-chloramine and quaternary ammonium moieties exerts enhanced bactericidal activity.

    PubMed

    Li, Lingdong; Pu, Tianyun; Zhanel, George; Zhao, Nan; Ens, Werner; Liu, Song

    2012-09-01

    Considering the rise of antibiotic resistance, the development of new antibacterial agents with improved biocidal functions is urgently required. In this study, ionic 5,5-dimethylhydantoin (DMH) analogues containing either a quaternary ammonium moiety (2)-4) or a phosphonate functional group (5),-6), were designed and synthesized to investigate the possible enhancing effect of quaternary ammonium moieties on the antibacterial performance of N-chloramines. These ionic DMH analogues were converted to their N-chloramine counterparts either in free form or after being covalently immobilized on a polymer surface via the "click" chemistry method. In the subsequent antimicrobial assessment against multi-drug-resistant Escherichia coli (MDR-E. coli) and methicillin-resistant Staphylococcus aureus (MRSA), chlorinated 2 and 3, the cyclic N-chloramines with a structural cation, exhibited distinctly enhanced biocidal functions in solution and after immobilization on surfaces.

  1. Clostridium botulinum type A progenitor toxin binds to Intestine-407 cells via N-acetyllactosamine moiety.

    PubMed

    Kojima, Shoudou; Eguchi, Hironobu; Ookawara, Tomomi; Fujiwara, Noriko; Yasuda, Jun; Nakagawa, Kazuhiko; Yamamura, Takehira; Suzuki, Keiichiro

    2005-06-03

    Botulism is a highly fatal disease caused by the botulinum progenitor toxin. In this study, the role of oligosaccharides for the binding of botulinum type A progenitor toxin (type A PTX) to human intestinal cells was investigated. The binding of type A PTX to Intestine-407 cells was inhibited by the addition of N-acetyllactosamine, lactose, and galactose. Treatment of Intestine-407 cells with neuraminidase led to a significant increase in the binding of type A PTX, while further digestion of cell surface oligosaccharides by beta-galactosidase and beta-N-acetylhexosaminidase decreased the binding. These results indicate that the N-acetyllactosamine moiety is responsible for the binding of type A PTX. These findings were further confirmed by a binding assay using synthesized oligosaccharides. Interestingly, sialylation or fucosylation of oligosaccharides inhibited the binding of type A PTX. These data suggest that the type A PTX binds to intestinal cells via cell surface N-acetyllactosamine moiety.

  2. Subcellular compartmentalization of saccharide moieties in cultured normal and malignant cells

    PubMed Central

    1980-01-01

    We studied subcellular localization of saccharide moieties in cultured normal and malignant cells fixed in paraformaldehyde and treated with a nonionic detergent, using lectins specific for various surgar residues as probes in fluorescence microscopy. In normal cells, concanavalin A and Lens culinaris agglutinin, specific for mannose-rich carbohydrate cores in glycoproteins, labeled the endoplasmic reticulum as a wide perinuclear region. Other lectins, on the other hand, stained the Golgi apparatus as a juxtanuclear reticular structure. A similar compartmentalization was also seen in all malignant cells studied, although the Golgi apparatus in these cells was distinctly vesicular in appearance. Our results indicate that saccharide moieties in both normal and malignant cells are similarly compartmentalized, and thus speak in favor of a unidirectional subcellular flow for both membrane and secreted glycoconjugates. PMID:7372714

  3. Subcellular compartmentalization of saccharide moieties in cultured normal and malignant cells.

    PubMed

    Virtanen, I; Ekblom, P; Laurila, P

    1980-05-01

    We studied subcellular localization of saccharide moieties in cultured normal and malignant cells fixed in paraformaldehyde and treated with a nonionic detergent, using lectins specific for various surgar residues as probes in fluorescence microscopy. In normal cells, concanavalin A and Lens culinaris agglutinin, specific for mannose-rich carbohydrate cores in glycoproteins, labeled the endoplasmic reticulum as a wide perinuclear region. Other lectins, on the other hand, stained the Golgi apparatus as a juxtanuclear reticular structure. A similar compartmentalization was also seen in all malignant cells studied, although the Golgi apparatus in these cells was distinctly vesicular in appearance. Our results indicate that saccharide moieties in both normal and malignant cells are similarly compartmentalized, and thus speak in favor of a unidirectional subcellular flow for both membrane and secreted glycoconjugates.

  4. Statistical mechanical model of gas adsorption in porous crystals with dynamic moieties.

    PubMed

    Simon, Cory M; Braun, Efrem; Carraro, Carlo; Smit, Berend

    2017-01-17

    Some nanoporous, crystalline materials possess dynamic constituents, for example, rotatable moieties. These moieties can undergo a conformation change in response to the adsorption of guest molecules, which qualitatively impacts adsorption behavior. We pose and solve a statistical mechanical model of gas adsorption in a porous crystal whose cages share a common ligand that can adopt two distinct rotational conformations. Guest molecules incentivize the ligands to adopt a different rotational configuration than maintained in the empty host. Our model captures inflections, steps, and hysteresis that can arise in the adsorption isotherm as a signature of the rotating ligands. The insights disclosed by our simple model contribute a more intimate understanding of the response and consequence of rotating ligands integrated into porous materials to harness them for gas storage and separations, chemical sensing, drug delivery, catalysis, and nanoscale devices. Particularly, our model reveals design strategies to exploit these moving constituents and engineer improved adsorbents with intrinsic thermal management for pressure-swing adsorption processes.

  5. Synthesis and insect antifeedant activity of precocene derivatives with lactone moiety.

    PubMed

    Szczepanik, Maryla; Obara, Robert; Szumny, Antoni; Gabryś, Beata; Halarewicz-Pacan, Aleksandra; Nawrot, Jan; Wawrzeńczyk, Czesław

    2005-07-27

    Starting from precocenes I and II, four of their derivatives with a lactone moiety were obtained. The compounds have been assessed as antifeedants against several diverse insect species including the storage pests the confused flour beetle (Tribolium confusum Duv., larvae and adults), the granary weevil beetle (Sitophilus granarius L., adults), and the khapra beetle (Trogoderma granarium Ev., larvae) and against the herbivorous pest insects Colorado potato beetle (Leptinotarsa decemlineata Say, adults and larvae) and aphids (Myzus persicae Sulz.). Precocenes, especially precocene II, showed a very strong antifeedant effect against all storage pests and aphids. The introduction of a lactone moiety caused a decrease in antifeedant activity against these species. Both precocenes were moderately active against L. decemlineata adults. The best antifeedants to this species were precocene derivatives, especially iodolactones. The introduction of iodine into a molecule had a great effect on the antifeedant activity of those compounds.

  6. Observed Dependence of Colloid Detachment on the Concentration of Initially Attached Colloids and Collector Surface Heterogeneity in Porous Media.

    PubMed

    Li, Tiantian; Jin, Yan; Huang, Yuanfang; Li, Baoguo; Shen, Chongyang

    2017-03-07

    Sand column experiments were conducted to examine the effects of the concentration of attached colloids (CAC) on their subsequent detachment upon decreasing solution ionic strength (IS). Different pore volumes of latex microparticle suspensions were injected into the columns to allow different amounts of colloids to attach at ISs of 0.001, 0.01, and 0.2 M. Then, deionized water was introduced to release the attached colloids. Results show that the fraction of attachments that were reversible to reduction of IS (FRA) increased with increasing CAC at a given IS if the sand was extensively treated using acids to reduce surface charge heterogeneity. This indicates that colloids were preferentially immobilized in sites favoring irreversible attachment and then gradually occupied reversible sites. In contrast, the FRA decreased with increasing CAC at 0.001 M in sand without the acid treatment, illustrating the opposite attachment sequence. Scanning electron microscope examinations reveal that the concave regions favored irreversible colloid attachment. Reversible attachment is likely due to immobilization on flat surfaces with charge heterogeneities, retention in stagnation point regions via secondary minimum association, ripening in the acid-treated sand, and capture of colloids by protruding asperities with charge heterogeneity in the untreated sand. At ISs of 0.01 and 0.2 M, the FRA was essentially independent of CAC in the untreated sand because the colloids were randomly attached on the sand surfaces over time.

  7. Synthesis and properties of dicationic ionic liquids containing a siloxane structural moiety

    NASA Astrophysics Data System (ADS)

    Glukhov, L. M.; Krasovskiy, V. G.; Chernikova, E. A.; Kapustin, G. I.; Kustov, L. M.; Koroteev, A. A.

    2015-12-01

    Five new ionic liquids formed by doubly charged cations containing a siloxane moiety and bis(trifluoromethylsulfonyl) imide anion are synthesized and characterized. Their thermal stability is studied by means of TGA; melting points (glass transition temperatures) and densities are measured. The temperature dependences of kinematic viscosity of the obtained ionic liquids are presented along with their approximations by the Vogel-Tammann-Fulcher equation.

  8. Synthesis of new α aminophosphonate system bearing Indazole moiety and their biological activity.

    PubMed

    Ali, Nasir ali Shafakat; Zakir, Shaikh; Patel, Muqtadir; Farooqui, Mazahar

    2012-04-01

    We are reporting herein for the first time the synthesis of α-aminophosphonates containing Indazole moiety in two steps. In the first step, imines of substituted N-benzylidene-1-methyl-1H-indazole-3-carbohydrazide are synthesized and in the next step it has converted to α-aminophosphonates using chlorotrimethylsilane (TMSCl) and triethyl phosphite. Some of the synthesized derivatives are evaluated for antibacterial activity against different bacterial strains.

  9. Bond stability of the "undesirable" heteroatom-heteroatom molecular moieties for high-throughput screening libraries.

    PubMed

    Yu, Bo; Reynisson, Jóhannes

    2011-12-01

    Compounds containing heteroatom-heteroatom bonds are regarded as "undesirable" in drug discovery projects possibly due to their inherent fragility, i.e., low bond dissociation energies (BDEs). However, many marketed drugs contain these molecular moieties and it can therefore be argued that the drugs have stronger bonds than generic organic compounds. In this study heteroatom-heteroatom BDEs for marketed drugs and non-drugs are calculated using the Density Functional Theory (DFT). The compounds containing heteroatom-heteroatom moieties were separated into six groups, i.e., N-N, N-O, N-S, O-S, O-O and S-S. No statistical difference was found for the N-N, N-O and O-S groups between the drugs and non-drugs. A statistical significant difference of ∼10 kcal mol(-1)was observed for the N-S moiety however all of the compounds investigated were sulphonamides. No drugs with the O-O moiety were found and the generic organic compounds had very low average BDE (26.6 ± 4.0 kcal mol(-1)) explaining their absence. For the S-S scaffold not enough data was available to make a meaningful statistical analysis. The results indicate that low BDE is not the main factor why heteroatom-heteroatom compounds are excluded from drug discovery projects. A more plausible explanation is their electron rich nature which leaves them susceptible to electrophilic attack in biochemical assays, which often leads to false positives and renders this class of compounds "undesirable" in screening collections. However, by omitting these compounds valuable areas in chemical space can be overlooked.

  10. Complete amino acid sequence of the A chain of human complement-classical-pathway enzyme C1r.

    PubMed Central

    Arlaud, G J; Willis, A C; Gagnon, J

    1987-01-01

    The amino acid sequence of human C1r A chain was determined, from sequence analysis performed on fragments obtained from C1r autolytic cleavage, cleavage of methionyl bonds, tryptic cleavages at arginine and lysine residues, and cleavages by staphylococcal proteinase. The polypeptide chain has an N-terminal serine residue and contains 446 amino acid residues (Mr 51,200). The sequence data allow chemical characterization of fragments alpha (positions 1-211), beta (positions 212-279) and gamma (positions 280-446) yielded from C1r autolytic cleavage, and identification of the two major cleavage sites generating these fragments. Position 150 of C1r A chain is occupied by a modified amino acid residue that, upon acid hydrolysis, yields erythro-beta-hydroxyaspartic acid, and that is located in a sequence homologous to the beta-hydroxyaspartic acid-containing regions of Factor IX, Factor X, protein C and protein Z. Sequence comparison reveals internal homology between two segments (positions 10-78 and 186-257). Two carbohydrate moieties are attached to the polypeptide chain, both via asparagine residues at positions 108 and 204. Combined with the previously determined sequence of C1r B chain [Arlaud & Gagnon (1983) Biochemistry 22, 1758-1764], these data give the complete sequence of human C1r. PMID:3036070

  11. Coumarin-Induced DNA Ligation, Rearrangement to DNA Interstrand Crosslinks, and Photorelease of Coumarin Moiety.

    PubMed

    Sun, Huabing; Fan, Heli; Eom, Hyeyoung; Peng, Xiaohua

    2016-11-03

    Coumarin moieties react with thymine and cytosine in DNA by photoinduced [2+2] cycloaddition, which allows quantitative DNA interstrand crosslink (ICL) formation. Here, we report the application of coumarin analogues for DNA photoligation and the rearrangement of coumarin-induced ligation to ICL products. Both DNA sequences and the linker units at position 4 of the coumarin moieties affected coumarin-induced DNA photoligation. A flexible linker unit favored DNA ICL formation but led to inefficient photoligation, whereas coumarins without linker units greatly increased DNA photoligation efficiency. DNA photoligation induced by the coumarin moiety was photoswitchable. Ligation products were formed between coumarin and dT or dC upon 350 nm irradiation but reverted to the original single-stranded oligodeoxyribonucleotides (ODNs) upon 254 nm irradiation. Rearrangement of ligated ODNs into ICL products occurred during the switchable (350 nm/254 nm) processes. Additionally, photoinduced cleavage of coumarin 3 occurred with dC-3 cycloadducts upon 254 nm irradiation, which was confirmed by mass spectrometry analysis.

  12. Identifying all moiety conservation laws in genome-scale metabolic networks.

    PubMed

    De Martino, Andrea; De Martino, Daniele; Mulet, Roberto; Pagnani, Andrea

    2014-01-01

    The stoichiometry of a metabolic network gives rise to a set of conservation laws for the aggregate level of specific pools of metabolites, which, on one hand, pose dynamical constraints that cross-link the variations of metabolite concentrations and, on the other, provide key insight into a cell's metabolic production capabilities. When the conserved quantity identifies with a chemical moiety, extracting all such conservation laws from the stoichiometry amounts to finding all non-negative integer solutions of a linear system, a programming problem known to be NP-hard. We present an efficient strategy to compute the complete set of integer conservation laws of a genome-scale stoichiometric matrix, also providing a certificate for correctness and maximality of the solution. Our method is deployed for the analysis of moiety conservation relationships in two large-scale reconstructions of the metabolism of the bacterium E. coli, in six tissue-specific human metabolic networks, and, finally, in the human reactome as a whole, revealing that bacterial metabolism could be evolutionarily designed to cover broader production spectra than human metabolism. Convergence to the full set of moiety conservation laws in each case is achieved in extremely reduced computing times. In addition, we uncover a scaling relation that links the size of the independent pool basis to the number of metabolites, for which we present an analytical explanation.

  13. Polymeric media comprising polybenzimidazoles N-substituted with organic-inorganic hybrid moiety

    DOEpatents

    Klaehn, John R [Idaho Falls, ID; Peterson, Eric S [Idaho Falls, ID; Wertsching, Alan K [Idaho Falls, ID; Orme, Christopher J [Shelley, ID; Luther, Thomas A [Idaho Falls, ID; Jones, Michael G [Pocatello, ID

    2009-12-15

    A PBI compound includes imidazole nitrogens at least a portion of which are substituted with an organic-inorganic hybrid moiety may be included in a separator medium. At least 85% of the imidazole nitrogens may be substituted. The organic-inorganic hybrid moiety may be an organosilane moiety, for example, (R)Me.sub.2SiCH.sub.2-- where R is selected from among methyl, phenyl, vinyl, and allyl. The separatory medium may exhibit an H.sub.2, Ar, N.sub.2, O.sub.2, CH.sub.3, or CO.sub.2 gas permeability greater than the gas permeability of a comparable separatory medium comprising the PBI compound without substitution. The separatory medium may further include an electronically conductive medium and/or ionically conductive medium. The separatory medium may be used as a membrane (semi-permeable, permeable, and non-permeable), a barrier, an ion exhcange media, a filter, a gas chromatography coating (such as stationary phase coating in affinity chromatography), etc.

  14. Photocatalytic hydrogen evolution by a diiron hydrogenase model based on a peptide fragment of cytochrome c556 with an attached diiron carbonyl cluster and an attached ruthenium photosensitizer.

    PubMed

    Sano, Yohei; Onoda, Akira; Hayashi, Takashi

    2012-03-01

    It is of particular interest to mimic the process of intramolecular electron relay at the active site of [FeFe]-hydrogenase in order to understand the mechanism of the catalytic activity of H(2) evolution. We have recently focused on using the native CXXCH peptide sequence of the C-terminal segment of cytochrome c(556) as a platform which holds a diiron carbonyl cluster via two cysteines and have attached a ruthenium photosensitizer via a histidine. The modified peptide with the two metal moieties is found to act as the photocatalyst for H(2) evolution with a turnover number of ~9 over 2h at pH 8.5 in the presence of ascorbate as a sacrificial reagent.

  15. Dissociative electron attachment to water

    NASA Astrophysics Data System (ADS)

    Haxton, Daniel James

    Dissociative electron attachment to water, H2O+e-→ H+OH-3.27eV H2+O-3.56eV H-+OHX P2 4.35eVH+H+O-8.04e VH-+OH* S2 8.38eVH-+H+O 8.75eV 0.1 is a physical process that has been studied since 1930[1]. It may be viewed as an inherently is non-Born-Oppenheimer process, for the initial state belongs to the electronic continuum, and the final state is electronically bound. As such, it presents a particular challenge for theory. We present a first-principles theoretical treatment of this process, in which we calculate the cross sections for production of the three major atom - diatom products observed by experiment, H2 + O-, H- + OH (X 2pi), and H- + OH (2Sigma). These states comprise the bulk of the experimentally determined cross section. In the present work we employ a Born-Oppenheimer expansion of the wavefunction for nuclear and electronic motion, and treat both quantum mechanically. The adiabatic treatment of the electronic motion incorporates multiconfiguration, correlated wavefunctions and includes an explicit treatment of the electronic continuum. For the nuclear dynamics we incorporate the full dimensionality of nuclear motion, including the three internal degrees of freedom and the effect of rotation. This is the first ab initio treatment of dissociative electron attachment which incorporates more than one degree of freedom in the nuclear dynamics. The first step in our Born-Oppenheimer treatment is to calculate adiabatic potential energy surfaces for the three metastable electronic states which are involved, the 2B1, 2A1, and 2B 2 electronic Feshbach resonances. Global potential energy surfaces are defined which incorporate the results of fixed-nuclei, ab initio calculations: quantum-mechanical electron scattering calculations using the complex Kohn method are performed and augmented by the results of large-scale configuration-interaction calculations performed in a restricted Hilbert space. The global surfaces are defined by a very accurate fit combining a 35

  16. Activation of microcarrier-attached lymphocytes in microgravity

    NASA Technical Reports Server (NTRS)

    Bechler, B.; Cogoli, A.; Cogoli-Greuter, M.; Muller, O.; Hunzinger, E.; Criswell, S. B.

    1992-01-01

    A technology has been developed to achieve optimal attachment of adhesion-independent lymphocytes to microcarrier beads. The activation of T-lymphocytes by concanavalin A was tested under microgravity conditions in an experiment carried out in space during the first Spacelab Life Science Mission. Activation, measured as the synthesis of deoxyribonucleic acid (DNA) and the production of interferon-gamma, more than doubled in attached lymphocytes in microgravity. The depression of the activation discovered in previous space experiments is due to an impairment not of the lymphocyte but of the macrophage function. The system described here may be useful for radiobiological investigations on the effect of high-energy particles and for testing the efficiency of the immune system in humans during the long-duration space flight planned in the future. The biotechnological significance of the increased lymphokine production in space remains to be assessed.

  17. The mtmVUC genes of the mithramycin gene cluster in Streptomyces argillaceus are involved in the biosynthesis of the sugar moieties.

    PubMed

    González, A; Remsing, L L; Lombó, F; Fernández, M J; Prado, L; Braña, A F; Künzel, E; Rohr, J; Méndez, C; Salas, J A

    2001-02-01

    Mithramycin is a glycosylated aromatic polyketide produced by Streptomyces argillaceus, and is used as an antitumor drug. Three genes (mtmV, mtmU and mtmC) from the mithramycin gene cluster have been cloned, and characterized by DNA sequencing and by analysis of the products that accumulate in nonproducing mutants, which were generated by insertional inactivation of these genes. The mtm V gene codes for a 2,3-dehydratase that catalyzes early and common steps in the biosynthesis of the three sugars found in mithramycin (D-olivose, D-oliose and D-mycarose); its inactivation caused the accumulation of the nonglycosylated intermediate premithramycinone. The mtmU gene codes for a 4-ketoreductase involved in D-oliose biosynthesis, and its inactivation resulted in the accumulation of premithramycinone and premithramycin A , the first glycosylated intermediate which contains a D-olivose unit. The third gene, mtmC, is involved in D-mycarose biosynthesis and codes for a C-methyltransferase. Two mutants with lesions in the mtmC gene accumulated mithramycin intermediates lacking the D-mycarose moiety but containing D-olivose units attached to C-12a in which the 4-keto group is unreduced. This suggests that mtmC could code for a second enzyme activity, probably a D-olivose 4-ketoreductase, and that the glycosyltransferase responsible for the incorporation of D-olivose (MtmGIV) shows some degree of flexibility with respect to its sugar co-substrate, since the 4-ketoanalog is also transferred. A pathway is proposed for the biosynthesis of the three sugar moieties in mithramycin.

  18. Synthesis of bifunctional molecules containing [12]aneN3 and coumarin moieties as effective DNA condensation agents and new non-viral gene vectors.

    PubMed

    Yue, Pan; Zhang, Ying; Guo, Zhi-Fo; Cao, Ao-Cheng; Lu, Zhong-Lin; Zhai, Yong-Gong

    2015-04-21

    A series of bifunctional molecules with different combinations of macrocyclic polyamine [12]aneN3 and coumarin moieties, 4a/b and 5a/b, were synthesized by a two-step copper(I)-mediated alkyne–azide click reactions between 1,3,5-tris(azidomethyl)benzene and Boc-protected N-propynyl-[12]aneN3/7-propynyloxycoumarins. Agarose gel electrophoresis experiments indicated that bifunctional molecules 4b and 5b effectively induced complete plasmid DNA condensation at concentrations up to 40 μM. It was found that the structural variation had a major impact on the condensation behavior of these compounds. The electrostatic interaction involving the [12]aneN3 moiety can be compensated by the binding contribution of the coumarin units during the DNA condensation process. These two types of interaction showed different effects on the reversibility of DNA condensation. Results from studies using dynamic laser scattering, atomic force microscopy, and EB replacement assay further supported the above conclusion. Cytotoxicity assays on bifunctional compounds 4a/b and 5a/b indicated their low cytotoxicity. Results from cellular uptake and cell transfection experiments proved that bifunctional compounds 4b and 5b successfully served as non-viral gene vectors. Furthermore, methyl substituents attached to the coumarin unit (4b and 5b) greatly enhanced their DNA condensation capability and gene transfection. These bifunctional molecules, with the advantages of lower cytotoxicity, good water solubility, and potential structural modification, will have great potential for the development of new non-viral gene delivery agents.

  19. Attenuated Weight Gain with the Novel Analog of Olanzapine Linked to Sarcosinyl Moiety (PGW5) Compared to Olanzapine.

    PubMed

    Taler, Michal; Vered, Israel; Globus, Rea; Shbiro, Liat; Weizman, Abraham; Weller, Aron; Gil-Ad, Irit

    2016-01-01

    Olanzapine-induced weight gain is associated with atherosclerosis, hypertension, dyslipidemia, and diabetes. We synthesized a novel antipsychotic drug (PGW5) possessing an olanzapine moiety linked to sarcosine, a glycine transporter 1 inhibitor. In this study, we compared the metabolic effects of PGW5 and olanzapine in a female rat model of weight gain. Female rats were treated daily with oral olanzapine (4 mg/kg), PGW5 (25 mg/kg), or vehicle for 16 days. Behavioral tests were conducted on days 12-14. Biochemical analyses were performed at the end of the treatment. A significant increase in body weight was observed in the olanzapine-treated group, while the PGW5 group did not differ from the controls. The open field test showed hypo-locomotion in the olanzapine-treated animals as compared to PGW5 and control groups. A significant increase in hypothalamic protein expression of the neuropeptide Y5 receptor and a decrease in pro-opiomelanocortin messenger ribonucleic acid (mRNA) levels were detected following PGW5 treatment, but not after olanzapine administration. PGW5 appears to possess minor metabolic effects compared with the parent compound olanzapine. The differential modulation of brain peptides associated with appetite regulation is possibly involved in the attenuation of metabolic effects by PGW5.

  20. Characterization of N-linked oligosaccharides bearing sialyl lewis x moieties on an alternatively glycosylated form of soluble complement receptor type 1 (sCR1).

    PubMed

    Picard, M D; Pettey, C L; Marsh, H C; Thomas, L J

    2000-02-01

    We sought to produce a complement inhibitory protein possessing oligosaccharides specifically modified to contain the sialyl Lewis x (sLe(x)) moiety. This modified glycoprotein could combine anti-complement activity with the ability to inhibit selectin-mediated interactions and concentrate this activity to sites of activated endothelium where selectins are upregulated. Soluble complement receptor type 1 (sCR1), previously shown to be effective in inhibiting the complement cascade, was produced in a cell line capable of adding fucose to N-linked oligosaccharides in the alpha1-3 linkage, which is necessary for sLe(x) glycosylation. The glycoprotein purified from these cells was designated sCR1sLe(x), and may prove to be more effective than sCR1 in some clinical applications. Detailed analysis and characterization of sCR1sLe(x) was performed to confirm that the N-linked oligosaccharides possessed sLe(x) moieties and also to determine the extent of sLe(x) glycosylation. The glycoproteins were characterized by oligosaccharide profiling, sequencing, linkage analysis and quantified by differential enzymic digestion, using fluorophore-assisted carbohydrate electrophoresis. The major glycans were identified as biantennary oligosaccharides (including sialylated and non-core fucosylated glycans). The linkages of sialic acid and the branched fucose were analysed by digestion with linkage-specific enzymes and subsequent separation by electrophoresis. All data were consistent with the presence of sLe(x) moieties on the N-linked oligosaccharides of sCR1sLe(x). sCR1sLe(x) is a prime example of a recombinant protein expressed with oligosaccharides engineered for a specific biological function, and produced using a commercially viable method.

  1. Investigation of Electron Attachment in Polyatomic Molecules.

    DTIC Science & Technology

    1980-05-30

    ELECTRON TRAP ........ ..................... ... 41 APPENDIX B - INITIAL INVESTIGATION OF ELECTRON ATTACHMENT IN MOLYBDENUM HEXAFLUORIDE AND TUNGSTEN ...A13, 1000 (1976). 4 • 48 APPENDIX B INITIAL INVESTIGATION OF ELECTRON ATTACHMENT IN MOLYBDENUM HEXAFLUORIDE AND TUNGSTEN HEXAFLUORIDE B1. INTRODUCTION...22 5.1 SULFUR HEXAFLUORIDE . ............................... 22 5.2 MOLYBDENUM HEXAFLUORIDE

  2. 21 CFR 872.3165 - Precision attachment.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Precision attachment. 872.3165 Section 872.3165 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED... precision attachment or preformed bar is a device made of austenitic alloys or alloys containing 75...

  3. 21 CFR 872.3165 - Precision attachment.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Precision attachment. 872.3165 Section 872.3165 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED... precision attachment or preformed bar is a device made of austenitic alloys or alloys containing 75...

  4. Attachment Parenting: A Style That Works.

    ERIC Educational Resources Information Center

    Sears, William

    1995-01-01

    Discusses the benefits of attachment parenting, which emphasizes parental commitment, a low-stress pregnancy, childbirth preparation, breast-feeding with child-led weaning, prompt response to the baby's crying, flexible sleeping arrangements, close-knit father-mother-baby functioning, and the avoidance of detachment parenting. Attachment parenting…

  5. Internal Representational Models of Attachment Relationships.

    ERIC Educational Resources Information Center

    Crittenden, Patricia M.

    This paper outlines several properties of internal representational models (IRMs) and offers terminology that may help to differentiate the models. Properties of IRMs include focus, memory systems, content, cognitive function, "metastructure," quality of attachment, behavioral strategies, and attitude toward attachment. An IRM focuses on…

  6. An Attachment Perspective on Anger among Adolescents

    ERIC Educational Resources Information Center

    Konishi, Chiaki; Hymel, Shelley

    2014-01-01

    Extending John Bowlby's hypothesis that dysfunctional anger is a predictable outcome of insecure attachments to parents, this study investigated the relationship between current parent-adolescent attachment and both the experience and expression of anger. Participants included 776 students (379 boys and 397 girls) in grades 8-12. As predicted by…

  7. Stability of Attachment during the Preschool Period

    ERIC Educational Resources Information Center

    Moss, Ellen; Cyr, Chantal; Bureau, Jean-Francois; Tarabulsy, George M.; Dubois-Comtois, Karine

    2005-01-01

    Children's attachment patterns at early preschool age and 2 years later as well as factors related to stability-instability were examined in a diverse socioeconomic status French Canadian sample of 120 children. Attachment was assessed during 2 laboratory visits using separation-reunion procedures when the children were approximately 3.5 (J.…

  8. Genetic and Environmental Influences on Adolescent Attachment

    ERIC Educational Resources Information Center

    Fearon, Pasco; Shmueli-Goetz, Yael; Viding, Essi; Fonagy, Peter; Plomin, Robert

    2014-01-01

    Background: Twin studies consistently point to limited genetic influence on attachment security in the infancy period, but no study has examined whether this remains the case in later development. This study presents the findings from a twin study examining the relative importance of genetic and environmental influences on attachment in…

  9. Attachment and Socioemotional Problems in Middle Childhood

    ERIC Educational Resources Information Center

    Moss, Ellen; Lecompte, Vanessa

    2015-01-01

    In this article, we will evaluate the evidence concerning links between attachment and behavior problems in the middle childhood period. We will first provide a general introduction to the question of attachment and maladaptation in the middle childhood period, and then examine the recent empirical evidence with respect to both externalizing and…

  10. Attachment Representations and Time Perspective in Adolescence

    ERIC Educational Resources Information Center

    Laghi, Fiorenzo; D'Alessio, Maria; Pallini, Susanna; Baiocco, Roberto

    2009-01-01

    This study examines the relationship between attachment to parents and peers, time perspective and psychological adjustment in adolescence. 2,665 adolescents (M age = 17.03 years, SD = 1.48) completed self-report measures about parent and peer attachment, time perspective, sympathy and self-determination. Subjects were divided into four groups…

  11. Adolescent Self-Esteem, Attachment and Loneliness

    ERIC Educational Resources Information Center

    Dhal, Anubha; Bhatia, Sangeeta; Sharma, Vidhi; Gupta, Priyanka

    2007-01-01

    Objectives: To assess self-esteem, loneliness and attachment styles among adolescents and examine their association with each other and with age and gender. Method: Adolescents (55 males and 55 females) from a public school in Delhi, aged 10-13 years were administered Coopersmith Self-Esteem Inventory (School Form), Attachment Scale and UCLA…

  12. An Attachment Model of University Connectedness

    ERIC Educational Resources Information Center

    Wilson, Steffen; Gore, Jonathan

    2013-01-01

    Students with high levels of connectedness to the university have been found to be more likely to complete their college degree than are students with low levels of university connectedness. This study examined the role of parental and peer attachment as distal predictors of school connectedness. As predicted, it was found that attachment style to…

  13. Ethnic Attachment among Second Generation Korean Americans.

    ERIC Educational Resources Information Center

    Hong, Joann; Min, Pyong Gap

    1999-01-01

    Describes the levels of second-generation Korean-American adolescents' (n=approximately 237) cultural, social, and psychological dimensions of attachment and examines the major factors highly correlated with two of the dimensions of ethnic attachment: use of the Korean language and Korean friendships. Findings support the view that high levels of…

  14. Psychophysical Scaling of Attachment and Loss.

    ERIC Educational Resources Information Center

    Tarnai, John

    Few studies have attempted to measure the strength of attachment in personal relationships or the stress associated with the loss of those relationships. To measure the perceived strength of attachment and stress of loss of 20 typical relationships (e.g.,wife or husband, father, son, daughter, brother, sister, friend, lover, grandparents, and…

  15. Attachment Disorder, Basic Trust and Educational Psychology

    ERIC Educational Resources Information Center

    King, Michael G.; Newnham, Karyn

    2008-01-01

    The label Attachment Disorder (AD) is used as either a description of a child's presentation, or as a diagnostic category. It is unclear whether this label is intended to be identical with the DSM-IV Reactive Attachment Disorder (RAD) diagnostic category, or if it is a separate diagnosis based on Randolph's Questionnaire and the premises…

  16. Parent-Child Attachment and Emotion Regulation

    ERIC Educational Resources Information Center

    Brumariu, Laura E.

    2015-01-01

    Given the centrality of both parent-child attachment and emotion regulation in children's development and adjustment, it is important to evaluate the relations between these constructs. This article discusses conceptual and empirical links between attachment and emotion regulation in middle childhood, highlights progress and challenges in the…

  17. Loss and Disorganization from an Attachment Perspective

    ERIC Educational Resources Information Center

    Thomson, Paula

    2010-01-01

    In this article, it is hypothesized that disorganizing, disorienting, and unresolved states of mind about loss experiences, as classified by the Adult Attachment Interview (AAI) coding system, may offer insight into the bereaved mind and may guide clinical treatment approaches. This article discusses pre-loss attachment organizations and the…

  18. Electron Scattering Resonances and Dissociative Attachment in Polyatomic Molecules.

    NASA Astrophysics Data System (ADS)

    Olthoff, James Kenneth

    The electronic structure and bonding character of a molecule may be understood from the energies of the frontier molecular orbitals. Photoelectron spectroscopy has produced a wealth of information about the occupied molecular orbitals, but the unoccupied molecular orbitals have, until recently, been largely ignored. A relatively new technique, electron transmission spectroscopy, is now being used to investigate the unoccupied valence molecular orbitals of many chemical compounds. Electron transmission spectroscopy measures the energy of negative ion states which arise from electron capture into unoccupied molecular orbitals. Additional information about the unoccupied orbitals may be obtained if the negative ion decays by way of dissociation. Determination of the identity, kinetic energy, and production rates of stable ion fragments supplies information about the shape and position of the potential energy curves which describe the electronic states of the molecule and the anion. Used together, photoelectron, electron transmission, and dissociation data can produce a complete picture of a molecule's valence electronic structure. For this work a time-of-flight mass spectrometer has been attached to an electron transmission spectrometer to observe negative ion fragments due to dissociative attachment. The mass spectrometer measures the identity and kinetic energy of stable negative ions as a function of incident electron energy. Electron transmission spectra and ion production data have been acquired for many compounds in four chemical categories. Halogen-substituted unsaturated hydrocarbons have been studied to determine the relation between (pi)* anion states and stable ion production. Halogen substituted methanes were examined to determine how (sigma) bonding affects dissociative attachment. Spectra for a series of boron trihalides were obtained to determine correlations between electron transmission data and Lewis acidity. Lastly, substituted metal carbonyls were

  19. Adult Attachment, Culturally Adjusted Attachment, and Interpersonal Difficulties of Taiwanese Adults

    ERIC Educational Resources Information Center

    Wang, Chia-Chih DC; Scalise, Dominick A.

    2010-01-01

    This study examines the applicability of Western adult attachment perspectives to interpersonal difficulties experienced by individuals with indigenous Chinese cultural backgrounds. A total of 275 Taiwanese university students completed self-report surveys of adult attachment, ideal attachment, and interpersonal problems. Culturally adjusted…

  20. Correlates of Attachment at Age 3: Construct Validity of the Preschool Attachment Classification System

    ERIC Educational Resources Information Center

    Moss, Ellen; Bureau, Jean-Francois; Cyr, Chantal; Mongeau, Chantal; St-Laurent, Diane

    2004-01-01

    This study examined correlates of attachment at age 3 to further validate preschool separation-reunion measures. Three-year-olds (N = 150) and their mothers participated in a separation-reunion protocol, the Preschool Attachment Classification System (PACS: J. Cassidy & R. S. Marvin with the MacArthur Working Group on Attachment, 1992), and a…

  1. Attachment and Autism: Parental Attachment Representations and Relational Behaviors in the Parent-Child Dyad

    ERIC Educational Resources Information Center

    Seskin, Lynn; Feliciano, Eileen; Tippy, Gil; Yedloutschnig, Ruby; Sossin, K. Mark; Yasik, Anastasia

    2010-01-01

    While attachment research has demonstrated that parents' internal working models of attachment relationships tend to be transmitted to their children, affecting children's developmental trajectories, this study specifically examines associations between adult attachment status and observable parent, child, and dyadic behaviors among children with…

  2. Modular Architecture and Unique Teichoic Acid Recognition Features of Choline-Binding Protein L (CbpL) Contributing to Pneumococcal Pathogenesis

    PubMed Central

    Gutiérrez-Fernández, Javier; Saleh, Malek; Alcorlo, Martín; Gómez-Mejía, Alejandro; Pantoja-Uceda, David; Treviño, Miguel A.; Voß, Franziska; Abdullah, Mohammed R.; Galán-Bartual, Sergio; Seinen, Jolien; Sánchez-Murcia, Pedro A.; Gago, Federico; Bruix, Marta; Hammerschmidt, Sven; Hermoso, Juan A.

    2016-01-01

    The human pathogen Streptococcus pneumoniae is decorated with a special class of surface-proteins known as choline-binding proteins (CBPs) attached to phosphorylcholine (PCho) moieties from cell-wall teichoic acids. By a combination of X-ray crystallography, NMR, molecular dynamics techniques and in vivo virulence and phagocytosis studies, we provide structural information of choline-binding protein L (CbpL) and demonstrate its impact on pneumococcal pathogenesis and immune evasion. CbpL is a very elongated three-module protein composed of (i) an Excalibur Ca2+-binding domain -reported in this work for the very first time-, (ii) an unprecedented anchorage module showing alternate disposition of canonical and non-canonical choline-binding sites that allows vine-like binding of fully-PCho-substituted teichoic acids (with two choline moieties per unit), and (iii) a Ltp_Lipoprotein domain. Our structural and infection assays indicate an important role of the whole multimodular protein allowing both to locate CbpL at specific places on the cell wall and to interact with host components in order to facilitate pneumococcal lung infection and transmigration from nasopharynx to the lungs and blood. CbpL implication in both resistance against killing by phagocytes and pneumococcal pathogenesis further postulate this surface-protein as relevant among the pathogenic arsenal of the pneumococcus. PMID:27917891

  3. Modular Architecture and Unique Teichoic Acid Recognition Features of Choline-Binding Protein L (CbpL) Contributing to Pneumococcal Pathogenesis

    NASA Astrophysics Data System (ADS)

    Gutiérrez-Fernández, Javier; Saleh, Malek; Alcorlo, Martín; Gómez-Mejía, Alejandro; Pantoja-Uceda, David; Treviño, Miguel A.; Voß, Franziska; Abdullah, Mohammed R.; Galán-Bartual, Sergio; Seinen, Jolien; Sánchez-Murcia, Pedro A.; Gago, Federico; Bruix, Marta; Hammerschmidt, Sven; Hermoso, Juan A.

    2016-12-01

    The human pathogen Streptococcus pneumoniae is decorated with a special class of surface-proteins known as choline-binding proteins (CBPs) attached to phosphorylcholine (PCho) moieties from cell-wall teichoic acids. By a combination of X-ray crystallography, NMR, molecular dynamics techniques and in vivo virulence and phagocytosis studies, we provide structural information of choline-binding protein L (CbpL) and demonstrate its impact on pneumococcal pathogenesis and immune evasion. CbpL is a very elongated three-module protein composed of (i) an Excalibur Ca2+-binding domain -reported in this work for the very first time-, (ii) an unprecedented anchorage module showing alternate disposition of canonical and non-canonical choline-binding sites that allows vine-like binding of fully-PCho-substituted teichoic acids (with two choline moieties per unit), and (iii) a Ltp_Lipoprotein domain. Our structural and infection assays indicate an important role of the whole multimodular protein allowing both to locate CbpL at specific places on the cell wall and to interact with host components in order to facilitate pneumococcal lung infection and transmigration from nasopharynx to the lungs and blood. CbpL implication in both resistance against killing by phagocytes and pneumococcal pathogenesis further postulate this surface-protein as relevant among the pathogenic arsenal of the pneumococcus.

  4. Attachment, mating, and parenting : An evolutionary interpretation.

    PubMed

    Belsky, J

    1997-12-01

    A modern evolutionary perspective emphasizing life history theory and behavioral ecology is brought to bear on the three core patterns of attachment that are identified in studies of infants and young children in the Strange Situation and adults using the Adult Attachment Interview. Mating and parenting correlates of secure/autonomous, avoidant/dismissing, and resistant/preoccupied attachment patterns are reviewed, and the argument is advanced that security evolved to promote mutually beneficial interpersonal relations and high investment parenting; that avoidant/dismissing attachment evolved to promote opportunistic interpersonal relations and low-investment parenting; and that resistant/preoccupied attachment evolved to foster "helper-at-the-nest" behavior and indirect reproduction.

  5. Attachment, borderline personality, and romantic relationship dysfunction.

    PubMed

    Hill, Jonathan; Stepp, Stephanie D; Wan, Ming Wai; Hope, Holly; Morse, Jennifer Q; Steele, Miriam; Steele, Howard; Pilkonis, Paul A

    2011-12-01

    Previous studies have implicated attachment and disturbances in romantic relationships as important indicators for Borderline Personality Disorder (BPD). The current research extends our current knowledge by examining the specific associations among attachment, romantic relationship dysfunction, and BPD, above and beyond the contribution of emotional distress and nonromantic interpersonal functioning in two distinct samples. Study 1 comprised a community sample of women (N = 58) aged 25-36. Study 2 consisted of a psychiatric sample (N = 138) aged 21-60. Results from both Study 1 and Study 2 demonstrated that (1) attachment was specifically related to BPD symptoms and romantic dysfunction, (2) BPD symptoms were specifically associated with romantic dysfunction, and (3) the association between attachment and romantic dysfunction was statistically mediated by BPD symptoms. The findings support specific associations among attachment, BPD symptoms, and romantic dysfunction.

  6. The Antimicrobial Activity of Porphyrin Attached Polymers

    NASA Astrophysics Data System (ADS)

    Thompson, Lesley

    2008-03-01

    We are interested in testing the antimicrobial activity of a porphyrin that is attached to a polymer. The porphyrin (5-(4-carboxyphenyl)-10,15,20-tris-(4-pryridyl)) was synthesized from methyl 4-formyl benzoate, 4-pyridinecarboxaldehyde, and pyrrole and attached to a copolymer of polystyrene/poly(vinyl benzyl chloride), which was synthesized by free radical polymerization. The antimicrobial activity of the polymer-attached porphyrin was then determined for gram-negative E. Coli grown to 0.80 OD. In this procedure, glass slides were coated with polymer-attached porphyrin via dip-coating, and the E. Coli bacteria were plated in Luria Broth media. The plates were subsequently exposed to light overnight before they were incubated as porphyrins act as photo-sensitizers when irradiated with light. The polymer-attached porphyrin did exhibit antimicrobial activity and parameters that affect its efficiency will be discussed.

  7. Attached gingiva: histology and surgical augmentation.

    PubMed

    Oh, Se-Lim

    2009-01-01

    The keratinized attached gingiva provides the periodontium with increased resistance to external injury, contributes to the stabilization of the gingival margin, and aids in dissipating physiological forces exerted by the muscular fibers of the alveolar mucosa on the gingival tissues. Increasing attached gingiva should be strongly considered in cases where the patient's plaque control is compromised. The apically positioned flap, free gingival graft, and subepithelial connective tissue graft are the most common surgical procedures used for augmenting the zone of attached gingiva effectively and predictably. The newly obtained keratinized gingiva can be maintained for a long period; in addition, these periodontal procedures halt the progression of gingival recession and could lead to gaining more keratinized gingiva from creeping attachment after the surgery. This article reviews the biology of attached gingiva and presents cases related to the functional role of periodontal plastic surgery.

  8. Continuous monitoring of bacterial attachment

    NASA Technical Reports Server (NTRS)

    Koeing, D. W.; Mishra, S. K.; Pierson, D. L.

    1994-01-01

    A major concern with the Space Station Freedom (SSF) water supply system is the control of longterm microbial contamination and biofilm development in the water storage and distribution systems. These biofilms have the potential for harboring pathogens as well as microbial strains containing resistance factors that could negatively influence crew health. The proposed means for disinfecting the water system on SSF (iodine) may encourage the selection of resistant strains. In fact, biofilm bacteria were observed in water lines from the Space Shuttle Columbia (OV-102); therefore, an alternative remediation method is required to disinfect spacecraft water lines. A thorough understanding of colonization events and the physiological parameters that will influence bacteria adhesion is required. The limiting factor for development of this technology is the ability to continuously monitor adhesion events and the effects of biocides on sessile bacteria. Methods were developed to allow bacterial adhesion and subsequent biocidal treatment to be monitored continuously. This technique couples automated image analysis with a continuous flow of a bacterial suspension through an optical flow cell. A strain of Pseudomonas cepacia isolated from the water supply of the Space Shuttle Discovery (OV-103) during STS-39 was grown in a nitrogen-limited continuous culture. This culture was challenged continuously with iodine during growth, and the adhesion characteristics of this strain was measure with regard to flow rate. Various biocides (ozone, hypochlorite, and iodine) were added to the flow stream to evaluate how well each chemical removed the bacteria. After biocide treatment, a fresh bacterial suspension was introduced into the flow cell, and the attachment rate was evaluated on the previously treated surface. This secondary fouling was again treated with biocide to determine the efficacy of multiple batch chemical treatments in removing biofilm.

  9. Fluorescence-Based Bacterial Overlay Method for Simultaneous In Situ Quantification of Surface-Attached Bacteria▿

    PubMed Central

    Müller, Rainer; Gröger, Gerhard; Hiller, Karl-Anton; Schmalz, Gottfried; Ruhl, Stefan

    2007-01-01

    For quantification of bacterial adherence to biomaterial surfaces or to other surfaces prone to biofouling, there is a need for methods that allow a comparative analysis of small material specimens. A new method for quantification of surface-attached biotinylated bacteria was established by in situ detection with fluorescence-labeled avidin-D. This method was evaluated utilizing a silicon wafer model system to monitor the influences of surface wettability and roughness on bacterial adhesion. Furthermore, the effects of protein preadsorption from serum, saliva, human serum albumin, and fibronectin were investigated. Streptococcus gordonii, Streptococcus mitis, and Staphylococcus aureus were chosen as model organisms because of their differing adhesion properties and their clinical relevance. To verify the results obtained by this new technique, scanning electron microscopy and agar replica plating were employed. Oxidized and poly(ethylene glycol)-modified silicon wafers were found to be more resistant to bacterial adhesion than wafers coated with hydrocarbon and fluorocarbon moieties. Roughening of the chemically modified surfaces resulted in an overall increase in bacterial attachment. Preadsorption of proteins affected bacterial adherence but did not fully abolish the influence of the original surface chemistry. However, in certain instances, mostly with saliva or serum, masking of the underlying surface chemistry became evident. The new bacterial overlay method allowed a reliable quantification of surface-attached bacteria and could hence be employed for measuring bacterial adherence on material specimens in a variety of applications. PMID:17308176

  10. Electron attachment to the cytosine-centered DNA single strands: does base stacking matter?

    PubMed

    Gu, Jiande; Wang, Jing; Leszczynski, Jerzy

    2012-02-02

    Electron attachment to the trimer of nucleotide, dGpdCpdG, has been investigated by a quantum mechanical approach at a reliable level of theory. The study of the electron attached dGpdCpdG species demonstrates that cytosine contained DNA single strands have a strong tendency to capture low-energy electrons and to form electronically stable cytosine-centered radical anions. The comparative study of the model molecules pdCpdG and dGpdCp reveals that base stacking has little contribution to the adiabatic electron affinity (AEA) of cytosine in DNA single strands. Additionally, the base-base stacking does not affect the vertical detachment energy (VDE) of the cytosine-centered radicals. Intrastrand H-bonding is found to be critical in increasing the values of the AEA and VDE. However, base-base stacking is revealed to be important in enlarging the vertical electron affinity (VEA) of cytosine. The electron attachment to the cytosine moiety intensifies the intrastrand H-bonding between the neighboring G and C bases. This process disrupts the base-base stacking interaction in the radical anion of dGpdCpdG.

  11. Nanopatterned smart polymer surfaces for controlled attachment, killing, and release of bacteria.

    PubMed

    Yu, Qian; Cho, Janghwan; Shivapooja, Phanindhar; Ista, Linnea K; López, Gabriel P

    2013-10-09

    Model surfaces with switchable functionality based on nanopatterned, thermoresponsive poly(N-isopropylacrylamide) (PNIPAAm) brushes were fabricated using interferometric lithography combined with surface-initiated polymerization. The temperature-triggered hydration and conformational changes of nanopatterned PNIPAAm brushes reversibly modulate the spatial concealment and exposure of molecules that are immobilized in the intervals between nanopatterned brushes. A biocidal quaternary ammonium salt (QAS) was used to demonstrate the utility of nanopatterned PNIPAAm brushes to control biointerfacial interactions with bacteria. QAS was integrated into polymer-free regions of the substrate between nanopatterned PNIPAAm brushes. The biocidal efficacy and release properties of these surfaces were tested against Escherichia coli K12. Above the lower critical solution temperature (LCST) of PNIPAAm, desolvated, collapsed polymer chains facilitate the attachment of bacteria and expose QAS moieties that kill attached bacteria. Upon a reduction of the temperature below the LCST, swollen PNIPAAm chains promote the release of dead bacteria. These results demonstrate that nanopatterned PNIPAAm/QAS hybrid surfaces are model systems that exhibit an ability to undergo noncovalent, dynamic, and reversible changes in structure that can be used to control the attachment, killing, and release of bacteria in response to changes in temperature.

  12. Dismissive attachment and posttraumatic stress disorder among securely and insecurely attached Belgian security workers.

    PubMed

    Bogaerts, Stefan; Kunst, Maarten J J; Winkel, Frans W

    2009-12-01

    This study examined Posttraumatic Stress Disorder in relation to secure and insecure attachment styles based on data collected in a sample of 81 Belgian security workers. All had experienced one traumatic event in the previous year. The sample was divided into a securely attached and an insecurely attached group. The three PTSD symptom scales, Re-experiencing, Avoidance, and Hyperarousal, differentiated significantly between the two attachment groups; the dismissive attachment style was negatively related to PTSD. Individuals with a positive view of themselves and a negative view of others have less risk of developing PTSD than those with a fearful or preoccupied attachment style. A relationship between the dismissive attachment style with grandiose narcissism seems possible. Interest has been expressed in medical approaches; therefore, the importance of medical research on PTSD is emphasized.

  13. An attachment research perspective on ADHD.

    PubMed

    Kissgen, Ruediger; Franke, Sebastian

    2016-06-01

    Since the beginning of clinical attachment research in the mid-1980s the number of research projects in this area has been continuously increasing. The research questions so far can be allocated to numerous medical disciplines such as psychosomatic medicine, adult psychiatry or child and adolescent psychiatry. Recently, children with ADHD and their families have also become subjects of this branch of research. Their specific behavioral characteristics from early childhood on constitute unique challenges on the parent-child interaction. If these interactions develop in a suboptimal way, children may develop an insecure or even a disorganized attachment quality. The latter represents a risk factor for a clinically significant psychopathological development.This article initially presents basic principles of attachment theory and discusses the relevance of the cardinal symptoms of ADHD for clinical attachment research. Subsequently, it outlines and discusses the main results of existing research regarding attachment and ADHD. It concludes with a perspective on research questions that need to be addressed in the future with regard to a transgenerational model that highlights the importance of parental attachment representations to the development of children's attachment quality.

  14. Buccal attachment loss in Swedish adolescents.

    PubMed

    Källestål, C; Uhlin, S

    1992-08-01

    A case referent study was performed to identify factors connected with loss of buccal attachment in adolescents. The study group was identified among 18-year-olds who had participated 2 years earlier in a study of periodontal conditions in adolescents. The criterion for inclusion in the case group was buccal attachment loss (greater than or equal to 1 mm) in one or more sites. Information on 28 variables, identified earlier as being related to recessions, was collected in a clinical examination, interview and observation. The referent group consisted of 66 subjects and the case group of 71 subjects. The case group comprised 2 subgroups, one identified as having buccal attachment loss in 1987 and the other with attachment loss occurring in the years 1987-89. Statistical analyses, using the chi 2 test, logistic regression and a variance component model, were performed to detect factors related to buccal attachment loss. These factors were thin alveolar tissue, narrow width of the attached gingiva and presence of teeth with buccal displacement. The results indicate that the anatomy of the buccal alveolar process is related to the presence of buccal attachment loss in populations with a high level of oral hygiene. To evaluate the importance of possible risk factors or etiological factors for development of buccal loss of tooth support, prospective epidemiological or experimental studies are needed.

  15. [Synthesis and antituberculosis activity of the derivatives of glycoside steviolbioside from the plant Stevia rebaudiana and diterpenoid isosteviol containing hydrazone, hydrazide and pyridinoyl moieties].

    PubMed

    Kataev, V E; Strobykina, I Iu; Andreeva, O V; Garifullin, B F; Sharipova, R R; Mironov, V F; Chestnova, R V

    2011-01-01

    Conjugates of antitubercular drug Isoniazid (hydrazide of isonicotinic acid), nicotinic and alpha-picolinic acid hydrazides and glycoside steviolbioside from the plant Stevia rebaudiana as well as the product of its acid hydrolysis, diterpenoid isosteviol, were synthesized. Besides, isosteviol hydrazide and hydrazone derivatives as well as conjugates containing two isosteviol moieties connected by dihydrazide linker were also obtained. Both initial compounds and their synthetic derivatives inhibit the growth of Mycobacterium tuberculosis (H37Rv in vitro). The minimum concentration at which the growth of M. tuberculosis was inhibited by 100% (MIC) for stevioside and steviolbioside equals 7.5 and 3.8 microg/mL, respectively. MIC values for conjugates of the hydrazides of pyridine carbonic acids and steviolbioside as well as isosteviol are in the ranges 5-10 and 10-20 microg/mL, respectively. Maximum inhibitory effect against M. tuberculosis showed the conjugates of isosteviol and adipic acid dihydrazide (MIC values ranged from 1.7 to 3.1 microg/mL). Antitubercular activity of the compounds studied is higher than the activity of antitubercular drug Pyrizanamide (MIC = 12.5-20 microg/mL) but lower than the activity of antitubercular drug Isoniazid (MIC = 0.02-0.04 microg/mL).

  16. Firm but Slippery Attachment of Deinococcus geothermalis

    PubMed Central

    Kolari, M.; Schmidt, U.; Kuismanen, E.; Salkinoja-Salonen, M. S.

    2002-01-01

    Bacterial biofilms impair the operation of many industrial processes. Deinococcus geothermalis is efficient primary biofilm former in paper machine water, functioning as an adhesion platform for secondary biofilm bacteria. It produces thick biofilms on various abiotic surfaces, but the mechanism of attachment is not known. High-resolution field-emission scanning electron microscopy and atomic force microscopy (AFM) showed peritrichous adhesion threads mediating the attachment of D. geothermalis E50051 to stainless steel and glass surfaces and cell-to-cell attachment, irrespective of the growth medium. Extensive slime matrix was absent from the D. geothermalis E50051 biofilms. AFM of the attached cells revealed regions on the cell surface with different topography, viscoelasticity, and adhesiveness, possibly representing different surface layers that were patchily exposed. We used oscillating probe techniques to keep the tip-biofilm interactions as small as possible. In spite of this, AFM imaging of living D. geothermalis E50051 biofilms in water resulted in repositioning but not in detachment of the surface-attached cells. The irreversibly attached cells did not detach when pushed with a glass capillary but escaped the mechanical force by sliding along the surface. Air drying eliminated the flexibility of attachment, but it resumed after reimmersion in water. Biofilms were evaluated for their strength of attachment. D. geothermalis E50051 persisted 1 h of washing with 0.2% NaOH or 0.5% sodium dodecyl sulfate, in contrast to biofilms of Burkholderia cepacia F28L1 or the well-characterized biofilm former Staphylococcus epidermidis O-47. Deinococcus radiodurans strain DSM 20539T also formed tenacious biofilms. This paper shows that D. geothermalis has firm but laterally slippery attachment not reported before for a nonmotile species. PMID:11948162

  17. Subphthalocyanines Axially Substituted with a Tetracyanobuta-1,3-diene-Aniline Moiety: Synthesis, Structure, and Physicochemical Properties.

    PubMed

    Winterfeld, Kim A; Lavarda, Giulia; Guilleme, Julia; Sekita, Michael; Guldi, Dirk M; Torres, Tomás; Bottari, Giovanni

    2017-04-06

    A 1,1,4,4-tetracyanobuta-1,3-diene (TCBD)-aniline moiety has been introduced, for the first time, at the axial position of two subphthalocyanines (SubPcs) peripherally substituted with hydrogen (H12SubPc) or fluorine atoms (F12SubPc). Single-crystal X-ray analysis of both SubPc-TCBD-aniline systems showed that each conjugate is a racemic mixture of two atropisomers resulting from the almost orthogonal geometry adopted by the axial TCBD unit, which were separated by chiral high-performance liquid chromatography. Remarkably, the single-crystal X-ray structure of one atropisomer of each SubPc-TCBD-aniline conjugate has been solved, allowing to unambiguously assign the atropisomers' absolute configuration, something, to the best of our knowledge, unprecedented in TCBD-based conjugates. Moreover, the physicochemical properties of both SubPc-TCBD-aniline racemates have been investigated using a wide range of electrochemical as well as steady-state and time-resolved spectroscopic techniques. Each of the two SubPc-TCBD-aniline conjugates presents a unique photophysical feature never observed before in SubPc chemistry. As a matter of fact, H12SubPc-TCBD-aniline showed significant ground-state charge transfer interactions between the H12SubPc macrocycle and the electron-withdrawing TCBD unit directly attached at its axial position. In contrast, F12SubPc-TCBD-aniline gave rise to an intense, broad emission, which red shifts upon increasing the solvent polarity and stems from an excited complex (i.e., an exciplex). Such an exciplex emission, which has also no precedent in TCBD chemistry, results from intramolecular interactions in the excited state between the electron-rich aniline and the F12SubPc π-surface, two molecular fragments kept in spatial proximity by the "unique" three-dimensional geometry adopted by the F12SubPc-TCBD-aniline. Complementary transient absorption studies were carried out on both SubPc-TCBD-aniline derivatives, showing the occurrence, in both cases

  18. Arginine deiminase inhibits Porphyromonas gingivalis surface attachment.

    PubMed

    Cugini, Carla; Stephens, Danielle N; Nguyen, Daniel; Kantarci, Alpdogan; Davey, Mary E

    2013-02-01

    The oral cavity is host to a complex microbial community whose maintenance depends on an array of cell-to-cell interactions and communication networks, with little known regarding the nature of the signals or mechanisms by which they are sensed and transmitted. Determining the signals that control attachment, biofilm development and outgrowth of oral pathogens is fundamental to understanding pathogenic biofilm development. We have previously identified a secreted arginine deiminase (ADI) produced by Streptococcus intermedius that inhibited biofilm development of the commensal pathogen Porphyromonas gingivalis through downregulation of genes encoding the major (fimA) and minor (mfa1) fimbriae, both of which are required for proper biofilm development. Here we report that this inhibitory effect is dependent on enzymic activity. We have successfully cloned, expressed and defined the conditions to ensure that ADI from S. intermedius is enzymically active. Along with the cloning of the wild-type allele, we have created a catalytic mutant (ADIC399S), in which the resulting protein is not able to catalyse the hydrolysis of l-arginine to l-citrulline. P. gingivalis is insensitive to the ADIC399S catalytic mutant, demonstrating that enzymic activity is required for the effects of ADI on biofilm formation. Biofilm formation is absent under l-arginine-deplete conditions, and can be recovered by the addition of the amino acid. Taken together, the results indicate that arginine is an important signal that directs biofilm formation by this anaerobe. Based on our findings, we postulate that ADI functions to reduce arginine levels and, by a yet to be identified mechanism, signals P. gingivalis to alter biofilm development. ADI release from the streptococcal cell and its cross-genera effects are important findings in understanding the nature of inter-bacterial signalling and biofilm-mediated diseases of the oral cavity.

  19. Structure of bovine lactoperoxidase with a partially linked heme moiety at 1.98Å resolution.

    PubMed

    Singh, Prashant K; Sirohi, Harsh V; Iqbal, Naseer; Tiwari, Pragya; Kaur, Punit; Sharma, Sujata; Singh, Tej P

    2017-03-01

    Lactoperoxidase (LPO) is a member of mammalian heme peroxidase superfamily whose other members are myeloperoxidase (MPO), eosinophil peroxidase (EPO) and thyroid peroxidase (TPO). In these enzymes, the heme moiety is linked to protein through two or three covalent bonds. In the mature LPO, the heme moiety is linked to protein through two ester bonds with highly conserved glutamate and aspartate residues. The previously reported structures of LPO have confirmed the formation of two covalent linkages involving Glu258 and Asp108 with 1-methyl and 5-methyl groups of pyrrole rings A and C respectively. We report here a new form of structure of LPO where the covalent bond between Glu258 and 1-methyl group of pyrrole ring A is present only in a fraction of protein molecules. In this case, the side chain of Glu258 occupies two distinct positions, each of which has a 0.5 occupancy. In one position, it forms a normal ester covalent linkage while in the second position, the side chain of Glu258 is located in the middle of the substrate binding site on the distal heme side. In this position, the atom of the side chain of Glu258 forms several contacts with atoms of other residues and heme moiety. Out of the two observed positions of the side chain of Glu258, the former contributes to the stabilization of heme position and improved catalytic action of LPO while the latter is responsible for the reduced stability of the heme position as well as it blocks the substrate binding site.

  20. Electrochemical sensing of concanavalin A using a non-ionic surfactant with a maltose moiety.

    PubMed

    Sugawara, Kazuharu; Kadoya, Toshihiko; Kuramitz, Hideki

    2014-03-03

    To electrochemically detect concanavalin A (ConA), a new method was developed using mixed micelles between a non-ionic surfactant with a maltose moiety and electroactive daunomycin. The surfactants, in which the length of the alkyl chain was different, were n-decyl-β-D-maltoside, n-dodecyl-β-D-maltoside, and n-tetradecyl-β-D-maltoside. The measurement principle was due to the micelle breakdown caused by the binding between the ConA and maltose moieties. When ConA was combined with maltose moieties at a concentration of surfactant that was near the critical micelle concentration, the daunomycin that formed the micelles was moved to a solution from the micelles. As a result, the peak current of daunomycin increased as the concentration of ConA was increased. The mechanism was proposed using voltammetry, spectrometry, and gel filtration. The linear range using n-tetradecyl-β-D-maltoside was 2.0×10(-9) to 8.0×10(-8) M of ConA, and it was the most sensitive in the presence of the three surfactants. To examine whether selective binding took place, measurements with several proteins were carried out. The electrode responses of daunomycin were not influenced by the presence of 5.0×10(-6) M protein. Furthermore, this method could be applied to the determination of ConA in a serum, and to the measurement of sugar chains that can be combined with ConA on the cell surface.

  1. Nuclear reactor fuel rod attachment system

    DOEpatents

    Not Available

    1980-09-17

    A reusable system is described for removably attaching a nuclear reactor fuel rod to a support member. A locking cap is secured to the fuel rod and a locking strip is fastened to the support member. The locking cap has two opposing fingers shaped to form a socket having a body portion. The locking strip has an extension shaped to rigidly attach to the socket's body portion. The locking cap's fingers are resiliently deflectable. For attachment, the locking cap is longitudinally pushed onto the locking strip causing the extension to temporarily deflect open the fingers to engage the socket's body portion. For removal, the process is reversed.

  2. On the attached length of orifices

    NASA Astrophysics Data System (ADS)

    Komkin, A. I.; Mironov, M. A.; Yudin, S. I.

    2012-11-01

    The attached length of orifices in reactive mufflers has been estimated based on numerical calculations by the finite-element method. The numerical results for a diaphragm in a duct are compared with the theoretical data obtained by Rayleigh, Fock, Karal, and Ingard. The dependence of the attached length on the diaphragm thickness is given. The results obtained are generalized for the case in which the orifice is a Helmholtz resonator neck. The effect of the resonator length on the attached length of the neck is analyzed.

  3. Vibrationally Resolved Electron Attachment to Oxygen Clusters

    NASA Astrophysics Data System (ADS)

    Matejcik, S.; Kiendler, A.; Stampfli, P.; Stamatovic, A.; Märk, T. D.

    1996-10-01

    Highly monochromatized electrons (with 30 meV FWHM) are used in a crossed beam experiment to investigate electron attachment to oxygen clusters \\(O2\\)n at electron energies from approximately 0 to 2 eV. At energies close to zero, the attachment cross section for the reaction \\(O2\\)n+e-->O-2 rises strongly with decreasing electron energy compatible with s-wave electron capture to \\(O2\\)n. Peaks in the attachment cross section present at higher energies can be ascribed to vibrational levels of the oxygen anion. The vibrational spacings observed can be quantitatively accounted for by model calculations.

  4. Praziquantel inhibits Schistosoma mansoni attachment in vitro.

    PubMed

    da-Silva, S P; Noel, F

    1990-01-01

    Male adult Schistosoma mansoni worms were placed in a glass dish containing Tyrode solution and observed for 15 min after addition of praziquantel (0.01 to 1 microM). Praziquantel promoted a concentration- and time-dependent inhibition of sucker-mediated attachment of the worm. Attachment inhibition was correlated with shortening of the parasite. We propose that the rapid and total inhibition of worm attachment observed in vitro with 1 microM praziquantel indicates that therapeutic concentrations of this drug should promote a rapid hepatic shift, in vivo, which may facilitate host tissue reaction.

  5. Attachment of Agrobacteria to Grape Cells †

    PubMed Central

    Pu, Xin-An; Goodman, R. N.

    1993-01-01

    The presence of the Ti plasmid favorably influences the attachment of agrobacteria to grape callus cells, especially during the early stages of a 2-h incubation. Agrobacterium strains attached to a similar extent to both the crown gall-resistant cultivar (Catawba), Vitis labruscana, and the crown gall-susceptible cultivar (Chancellor), Vitis sp. Attachment of the virulent strain to grape callus cells is blocked by the avirulent strain HLB-2 in both the tissue culture cell suspension and the seedling root systems. PMID:16349016

  6. Synthesis of new simplified hemiasterlin derivatives with α,β-unsaturated carbonyl moiety.

    PubMed

    The, Chinh Pham; Thi, Tuyet Anh Dang; Hoang, Thi Phuong; Ngo, Quoc Anh; Doan, Duy Tien; Thi, Thu Ha Nguyen; Thi, Tham Pham; Thi, Thu Ha Vu; Jean, M; van de Weghe, P; Van, Tuyen Nguyen

    2014-05-15

    In this Letter, we report a convenient and efficient method for the synthesis of new simplified derivatives of hemiasterlin in which the α,α-dimethylbenzylic moiety A is replaced by α,β-unsaturated aryl groups as Michael acceptor. Most of these derivatives have a strong cytotoxic activity on three human tumor cell lines (KB, Hep-G2 and MCF7). Analogs 17b and 17f showed a high cytotoxicity against KB and Hep-G2 cancer cell lines comparable to paclitaxel and ellipticine.

  7. Wittig Reaction: Domino Olefination and Stereoselectivity DFT Study. Synthesis of the Miharamycins' Bicyclic Sugar Moiety.

    PubMed

    Cachatra, Vasco; Almeida, Andreia; Sardinha, João; Lucas, Susana D; Gomes, Ana; Vaz, Pedro D; Florêncio, M Helena; Nunes, Rafael; Vila-Viçosa, Diogo; Calhorda, Maria José; Rauter, Amélia P

    2015-11-20

    2-O-Acyl protected-d-ribo-3-uloses reacted with [(ethoxycarbonyl)methylene]triphenylphosphorane in acetonitrile to afford regio- and stereoselectively 2-(Z)-alkenes in 10-60 min under microwave irradiation. This domino reaction is proposed to proceed via tautomerization of 3-ulose to enol, acyl migration, tautomerization to the 3-O-acyl-2-ulose, and Wittig reaction. Alternatively, in chloroform, regioselective 3-olefination of 2-O-pivaloyl-3-uloses gave (E)-alkenes, key precursors for the miharamycins' bicyclic sugar moiety.

  8. Synthesis and evaluation of benzimidazole carbamates bearing indole moieties for antiproliferative and antitubulin activities.

    PubMed

    Guan, Qi; Han, Chunming; Zuo, Daiying; Zhai, Min'an; Li, Zengqiang; Zhang, Qian; Zhai, Yanpeng; Jiang, Xuewei; Bao, Kai; Wu, Yingliang; Zhang, Weige

    2014-11-24

    A series of novel benzimidazole carbamates bearing indole moieties with sulphur or selenium atoms connecting the aromatic rings were synthesised and evaluated for their antiproliferative activities against three human cancer cell lines (SGC-7901, A-549 and HT-1080) using an MTT assay. Compounds 10a, 10b, 7a, 7b and 7f showed significant activities against these cell lines. The most potent compound in this series, 10a, was selected to investigate its antitumour mechanism. In addition, molecular docking studies suggested that compound 10a interacts very closely with the nocodazole docking pose through hydrogen bonds at the colchicine binding site of tubulin.

  9. DIBALH mediated reduction of the acetal moiety on perhydrofuro[2,3-b]pyran derivatives.

    PubMed

    Marco-Contelles, J; Ruiz-Caro, J

    2001-09-21

    The reaction of DIBALH with bis(heteroannulated)-pyranosides containing the perhydrofuro[2,3-b]pyran moiety is described. The hydride attack at the anomeric carbon (C-9a) resulted in the exclusive tetrahydrofuran ring opening. The selectivity of this reaction has been evaluated as other benzylidene acetals built on these substrates remain practically or partially unaltered in these conditions depending on the steric volume of the O-protecting group located at C-4 (TBDMS vs. Me). This protocol can be considered as a new entry for the synthesis of chiral and highly functionalized cyclopentanes.

  10. High-speed AFM images of thermal motion provide stiffness map of interfacial membrane protein moieties.

    PubMed

    Preiner, Johannes; Horner, Andreas; Karner, Andreas; Ollinger, Nicole; Siligan, Christine; Pohl, Peter; Hinterdorfer, Peter

    2015-01-14

    The flexibilities of extracellular loops determine ligand binding and activation of membrane receptors. Arising from fluctuations in inter- and intraproteinaceous interactions, flexibility manifests in thermal motion. Here we demonstrate that quantitative flexibility values can be extracted from directly imaging the thermal motion of membrane protein moieties using high-speed atomic force microscopy (HS-AFM). Stiffness maps of the main periplasmic loops of single reconstituted water channels (AqpZ, GlpF) revealed the spatial and temporal organization of loop-stabilizing intraproteinaceous H-bonds and salt bridges.

  11. High-Speed AFM Images of Thermal Motion Provide Stiffness Map of Interfacial Membrane Protein Moieties

    PubMed Central

    2014-01-01

    The flexibilities of extracellular loops determine ligand binding and activation of membrane receptors. Arising from fluctuations in inter- and intraproteinaceous interactions, flexibility manifests in thermal motion. Here we demonstrate that quantitative flexibility values can be extracted from directly imaging the thermal motion of membrane protein moieties using high-speed atomic force microscopy (HS-AFM). Stiffness maps of the main periplasmic loops of single reconstituted water channels (AqpZ, GlpF) revealed the spatial and temporal organization of loop-stabilizing intraproteinaceous H-bonds and salt bridges. PMID:25516527

  12. Tetranuclear organometallic complexes containing Mo2O4(2+) and allylmolybdenum(II) moieties.

    PubMed

    Paredes, Paloma; López-Calzada, Angel; Miguel, Daniel; Villafañe, Fernando

    2010-11-14

    Refluxing toluene solutions of [Mo(η(3)-allyl)(O(2)CMe)(CO)(2)(pz*H)(2)] (pz*H = pzH, pyrazole, or dmpzH, 3,5-dimethylpyrazole) without exclusion of air, give the tetranuclear complexes [Mo(2)O(2)(O(2)CCH(3))(2){(μ(3)-O)(μ-pz*)Mo(η(3)-allyl)(CO)(2)(pz*H)}(2)], where two chelating acetato ligands and two "Mo(η(3)-allyl)(CO)(2)(pz*H)(μ-pz*)" fragments are bonded to a central Mo(2)O(4)(2+) moiety.

  13. Intervalence transfer of ferrocene moieties adsorbed on electrode surfaces by a conjugated linkage

    NASA Astrophysics Data System (ADS)

    Chen, Wei; Brown, Lauren E.; Konopelski, Joseph P.; Chen, Shaowei

    2009-03-01

    Effective intervalence transfer occurred between the metal centers of ferrocene moieties that were adsorbed onto a ruthenium thin film surface by ruthenium-carbene π bonds, a direct verification of Hush's four-decade-old prediction. Electrochemical measurements showed two pairs of voltammetric peaks where the separation of the formal potentials suggested a Class II behavior. Additionally, the potential spacing increased with increasing ferrocene surface coverage, most probably as a consequence of the enhanced contribution from through-space electronic interactions between the metal centers. In contrast, the incorporation of a sp 3 carbon spacer into the ferrocene-ruthenium linkage led to the diminishment of interfacial electronic communication.

  14. Chemical Synthesis and Biological Activities of Novel Pleuromutilin Derivatives with Substituted Amino Moiety

    PubMed Central

    Shang, Ruofeng; Wang, Shengyu; Xu, Ximing; Yi, Yunpeng; Guo, Wenzhu; YuLiu; Liang, Jianping

    2013-01-01

    Novel pleuromutilin derivatives designed based on the structure of valnemulin were synthesized and evaluated for their in vitro antibacterial activities. These pleuromutilin derivatives with substituted amino moiety exhibited excellent activities against methicillin-resistant Staphylococcus aureus, methicillin-resistant Staphylococcus epidermidis, Escherichia coli, and Streptococcus agalactiae. Compound 5b showed the highest antibacterial activities and even exceeded tiamulin. Moreover, the docking experiments provided information about the binding model between the synthesized compounds and peptidyl transferase center (PTC) of 23S rRNA. PMID:24376551

  15. Attachment and Children: Citations From Selected Data Bases.

    ERIC Educational Resources Information Center

    Baskin, Linda B., Comp.

    This bibliography compiles citations from seven selected data bases on the topic of attachment and children. The citations are grouped into eight categories: (1) Attachment -- General; (2) Institutions -- Hospitals, Prisons; (3) Day Care and Attachment; (4) Handicapped Children and Attachment; (5) Separation; (6) Child Abuse and Attachment; (7)…

  16. Give Them Roots, Then Let Them Fly: Understanding Attachment Therapy.

    ERIC Educational Resources Information Center

    McKelvey, Carole A., Ed.

    This book describes attachment theory, presents the attachment therapy program in place at the Evergreen Attachment Center at Evergreen, Colorado, and examines the implications of attachment therapy. The chapters are: (1) "An Overview" (Carole A. McKelvey, John Alston); (2) "Attachment Theory and Assessment" (Michael Orlans,…

  17. Attachment of Oral Cytophaga Species to Hydroxyapatite-Containing Surfaces

    PubMed Central

    Celesk, Roger A.; London, Jack

    1980-01-01

    Model systems simulating the cementum portion of teeth were used to characterize the attachment process by which certain species of oral Cytophaga initiate the colonization of the tooth root surface in vitro. The adsorption of these bacteria to spheroidal hydroxyapatite beads and mechanically powdered root material followed Langmuir isotherm kinetics. From such data, the number of binding sites per 20 mg of substrate and the affinity constants were evaluated for two strains of Cytophaga sp. Resting cells of the two strains tested adhered relatively tenaciously to hydroxyapatite beads in numbers similar to those observed with cells of Streptococcus sanguis. Attachment of bacteria to the substrates was partially inhibited by (i) coating the substrates with human serum or saliva, (ii) pretreating cell suspensions with proteinase K or phospholipase C or D, or (iii) exposing the cells to temperatures greater than 60°C for 15 min. Treating resting cell suspensions with pronase, neuraminidase, phospholipase A2, or 0.1 M ethylenediaminetetraacetic acid had no effect on the attachment process. ImagesFig. 1Fig. 3Fig. 5 PMID:7216436

  18. Multiple roles of genome-attached bacteriophage terminal proteins

    SciTech Connect

    Redrejo-Rodríguez, Modesto; Salas, Margarita

    2014-11-15

    Protein-primed replication constitutes a generalized mechanism to initiate DNA or RNA synthesis in linear genomes, including viruses, gram-positive bacteria, linear plasmids and mobile elements. By this mechanism a specific amino acid primes replication and becomes covalently linked to the genome ends. Despite the fact that TPs lack sequence homology, they share a similar structural arrangement, with the priming residue in the C-terminal half of the protein and an accumulation of positively charged residues at the N-terminal end. In addition, various bacteriophage TPs have been shown to have DNA-binding capacity that targets TPs and their attached genomes to the host nucleoid. Furthermore, a number of bacteriophage TPs from different viral families and with diverse hosts also contain putative nuclear localization signals and localize in the eukaryotic nucleus, which could lead to the transport of the attached DNA. This suggests a possible role of bacteriophage TPs in prokaryote-to-eukaryote horizontal gene transfer. - Highlights: • Protein-primed genome replication constitutes a strategy to initiate DNA or RNA synthesis in linear genomes. • Bacteriophage terminal proteins (TPs) are covalently attached to viral genomes by their primary function priming DNA replication. • TPs are also DNA-binding proteins and target phage genomes to the host nucleoid. • TPs can also localize in the eukaryotic nucleus and may have a role in phage-mediated interkingdom gene transfer.

  19. Magnetically Attached Multifunction Maintenance Rover

    NASA Technical Reports Server (NTRS)

    Bar-Cohen, Yoseph; Joffe, Benjamin

    2005-01-01

    A versatile mobile telerobot, denoted the magnetically attached multifunction maintenance rover (MAGMER), has been proposed for use in the inspection and maintenance of the surfaces of ships, tanks containing petrochemicals, and other large ferromagnetic structures. As its name suggests, this robot would utilize magnetic attraction to adhere to a structure. As it moved along the surface of the structure, the MAGMER would perform tasks that could include close-up visual inspection by use of video cameras, various sensors, and/or removal of paint by water-jet blasting, laser heating, or induction heating. The water-jet nozzles would be mounted coaxially within compressed-air-powered venturi nozzles that would collect the paint debris dislodged by the jets. The MAGMER would be deployed, powered, and controlled from a truck, to which it would be connected by hoses for water, compressed air, and collection of debris and by cables for electric power and communication (see Figure 1). The operation of the MAGMER on a typical large structure would necessitate the use of long cables and hoses, which can be heavy. To reduce the load of the hoses and cables on the MAGMER and thereby ensure its ability to adhere to vertical and overhanging surfaces, the hoses and cables would be paid out through telescopic booms that would be parts of a MAGMER support system. The MAGMER would move by use of four motorized, steerable wheels, each of which would be mounted in an assembly that would include permanent magnets and four pole pieces (see Figure 2). The wheels would protrude from between the pole pieces by only about 3 mm, so that the gap between the pole pieces and the ferromagnetic surface would be just large enough to permit motion along the surface but not so large as to reduce the magnetic attraction excessively. In addition to the wheel assemblies, the MAGMER would include magnetic adherence enhancement fixtures, which would comprise arrays of permanent magnets and pole pieces

  20. Carbon Nanotubes Covalently Attached to Functionalized Surfaces Directly through the Carbon Cage.

    PubMed

    Williams, Mackenzie G; Gao, Fei; BenDhiab, Ibtihel; Teplyakov, Andrew

    2017-02-07

    The covalent attachment of nonfunctionalized and carboxylic acid-functionalized carbon nanotubes to amine-terminated organic monolayers on gold and silicon surfaces is investigated. It is well established that the condensation reaction between a carboxylic acid and an amine is a viable method to anchor carbon nanotubes to solid substrates. The work presented here shows that the presence of the carboxylic group on the nanotube is not required for attachment to occur, as direct attachment via the substrate amine and the nanotube cage can take place. Scanning and transmission electron microscopy and atomic force microscopy confirm the presence of carbon nanotubes in intimate contact with the surface. X-ray photoelectron spectroscopy is utilized to compare the surface chemistry of the functionalized and nonfunctionalized carbon nanotubes and is supported by a computational investigation. Ion fragments attributed to the direct attachment between the surface and carbon nanotube cage are detected by time-of-flight secondary ion mass spectrometry. The overall attachment scheme is evaluated and can be further used on multiple carbonaceous materials attached to solid substrates.

  1. Higher biomass productivity of microalgae in an attached growth system, using wastewater.

    PubMed

    Lee, Seung-Hoon; Oh, Hee-Mock; Jo, Beom-Ho; Lee, Sang-A; Shin, Sang-Yoon; Kim, Hee-Sik; Lee, Sang-Hyup; Ahn, Chi-Yong

    2014-11-28

    Although most algae cultivation systems are operated in suspended culture, an attached growth system can offer several advantages over suspended systems. Algal cultivation becomes light-limited as the microalgal concentration increases in the suspended system; on the other hand, sunlight penetrates deeper and stronger in attached systems owing to the more transparent water. Such higher availability of sunlight makes it possible to operate a raceway pond deeper than usual, resulting in a higher areal productivity. The attached system achieved 2.8-times higher biomass productivity and total lipid productivity of 9.1 g m(-2) day(-1) and 1.9 g m(-2) day(-1), respectively, than the suspended system. Biomass productivity can be further increased by optimization of the culture conditions. Moreover, algal biomass harvesting and dewatering were made simpler and cheaper in attached systems, because mesh-type substrates with attached microalgae were easily removed from the culture and the remaining treated wastewater could be discharged directly. When the algal biomass was dewatered using natural sunlight, the palmitic acid (C16:0) content increased by 16% compared with the freeze-drying method. There was no great difference in other fatty acid composition. Therefore, the attached system for algal cultivation is a promising cultivation system for mass biodiesel production.

  2. Clinical evaluation of mandibular implant overdentures via Locator implant attachment and Locator bar attachment

    PubMed Central

    Seo, Yong-Ho; Bae, Eun-Bin; Kim, Jung-Woo; Lee, So-Hyoun; Jeong, Chang-Mo; Jeon, Young-Chan

    2016-01-01

    PURPOSE The aim of this study was to evaluate the clinical findings and patient satisfaction on implant overdenture designed with Locator implant attachment or Locator bar attachment in mandibular edentulous patients. MATERIALS AND METHODS Implant survival rate, marginal bone loss, probing depth, peri-implant inflammation, bleeding, plaque, calculus, complications, and satisfaction were evaluated on sixteen patients who were treated with mandibular overdenture and have used it for at least 1 year (Locator implant attachment: n=8, Locator bar attachment: n=8). RESULTS Marginal bone loss, probing depth, plaque index of the Locator bar attachment group were significantly lower than the Locator implant attachment group (P<.05). There was no significant difference on bleeding, peri-implant inflammation, and patient satisfaction between the two denture types (P>.05). The replacement of the attachment components was the most common complication in both groups. Although there was no correlation between marginal bone loss and plaque index, a significant correlation was found between marginal bone loss and probing depth. CONCLUSION The Locator bar attachment group indicates lesser marginal bone loss and need for maintenance, as compared with the Locator implant attachment group. This may be due to the splinting effect among implants rather than the types of Locator attachment. PMID:27555901

  3. Oxalone and lactone moieties of podophyllotoxin exhibit properties of both the B and C rings of colchicine in its binding with tubulin.

    PubMed

    Gupta, Suvroma; Das, Lalita; Datta, Ajit B; Poddar, Asim; Janik, Mark E; Bhattacharyya, Bhabatarak

    2006-05-23

    Thermodynamics of podophyllotoxin binding to tubulin and its multiple points of attachment with tubulin has been studied in detail using isothermal titration calorimetry. The calorimetric enthalpy of the association of podophyllotoxin with tubulin is negative and occurs with a negative heat capacity change (DeltaC(p) = -2.47 kJ mol(-)(1) K(-)(1)). The binding is unique with a simultaneous participation of both hydrophobic and hydrogen-bonding forces with unfavorable negative entropic contribution at higher temperature, favored with an enthalpy-entropy compensation. Interestingly, the binding of 2-methoxy-5-(2',3',4'-trimethoxyphenyl)tropone (AC, a colchicine analogue without the B ring) with tubulin is enthalpy-favored. However, the podophyllotoxin-tubulin association depending upon the temperature of the reaction has a favorable entropic and enthalpic component, which resembles both B- and C-ring properties of colchicine. On the basis of the crystal structure of the podophyllotoxin-tubulin complex, distance calculations have indicated a possible interaction between threonine 179 of alpha-tubulin and the hydroxy group on the D ring of podophyllotoxin. To confirm the involvement of the oxalone moiety as well as the lactone ring of podophyllotoxin in tubulin binding, analogues of podophyllotoxin are synthesized with methoxy substitution at the 4' position of ring D along with its isomer and another analogue epimerized at ring E. From these results, involvement of oxalone as well as the lactone ring of the drug in a specific orientation inclusive of ring A is indicated for podophyllotoxin-tubulin binding. Therefore, podophyllotoxin, like colchicine, behaves as a bifunctional ligand having properties of both the B and C rings of colchicine by making more than one point of attachment with the protein tubulin.

  4. 21 CFR 872.3165 - Precision attachment.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... precision attachment or preformed bar is a device made of austenitic alloys or alloys containing 75 percent or greater gold and metals of the platinum group intended for use in prosthetic dentistry...

  5. Modified transmitter attachment method for adult ducks

    USGS Publications Warehouse

    Pietz, P.J.; Brandt, D.A.; Krapu, G.L.; Buhl, D.A.

    1995-01-01

    The value of radio telemetry for waterfowl research depends on the availability of suitable methods of attaching transmitters. In previous studies, external transmitters attached to adult Mallards (Anas platyrhynchos) with sutures and glue did not stay on birds reliably. In an attempt to improve transmitter retention, a method of attachment was tested in which 4-g transmitters were attached mid-dorsally with sutures and with a stainless steel anchor-shaped wire inserted subcutaneously (anchor transmitters). Field tests indicated that all of 26 female Mallards and 63 of 65 female Gadwalls (Anas strepera) retained their anchor transmitters during 4369 bird-days of monitoring during nesting and brood rearing. Survival rates of females with anchor transmitters compared favorably with those reported from other studies. In this study, females with and without anchor transmitters did not differ with respect to survival rates of their ducklings. The anchor transmitter may be suitable for a variety of field studies on numerous species.

  6. Accentuating the positive in adult attachments.

    PubMed

    Sable, Pat

    2007-12-01

    This paper proposes that attachment theory, with its emphasis on stability and security, accentuates the positive aspects of affectional relationships and suggests a way to look at the process of adult psychotherapy. Attachment-based research has shown that positive attachment experiences are related to feelings of joy, comfort, and contentment throughout life. In contrast, experiences that are hurtful or traumatic, and especially if they are chronic or repeated, can have negative effects on thoughts and emotions as well as the body. In applying these findings to psychotherapy, the role of the therapist can be seen as providing a positive emotional experience within which to examine and gain a new perspective on the origins and development of distress. Through therapy, the opportunity to experience a relationship of secure attachment enhances psychological and physical well-being and the capacity to make and maintain lasting affectional bonds with others.

  7. Personality disorders, attachment and psychodynamic psychotherapy.

    PubMed

    Weinstein, Lissa; Perez-Rodriguez, M Mercedes; Siever, Larry

    2014-01-01

    While attachment has been a fruitful and critical concept in understanding enduring individual templates for interpersonal relationships, it does not have a well-understood relationship to personality disorders, where impairment of interpersonal functioning is paramount. Despite the recognition that attachment disturbances do not simply reflect nonoptimal caretaking environments, the relationship of underlying temperamental factors to these environmental insults has not been fully explored. In this paper we provide an alternate model for the role of neurobiological temperamental factors, including brain circuitry and neuropeptide modulation, in mediating social cognition and the internalization and maintenance of attachment patterns. The implications of these altered attachment patterns on personality disorders and their neurobiological and environmental roots for psychoanalytically based treatment models designed to ameliorate difficulties in interpersonal functioning through the medium of increased access to mature forms of mentalization is discussed.

  8. Emergence of tempered preferential attachment from optimization

    PubMed Central

    D'Souza, Raissa M.; Borgs, Christian; Chayes, Jennifer T.; Berger, Noam; Kleinberg, Robert D.

    2007-01-01

    We show how preferential attachment can emerge in an optimization framework, resolving a long-standing theoretical controversy. We also show that the preferential attachment model so obtained has two novel features, saturation and viability, which have natural interpretations in the underlying network and lead to a power-law degree distribution with exponential cutoff. Moreover, we consider a generalized version of this preferential attachment model with independent saturation and viability, leading to a broader class of power laws again with exponential cutoff. We present a collection of empirical observations from social, biological, physical, and technological networks, for which such degree distributions give excellent fits. We suggest that, in general, optimization models that give rise to preferential attachment with saturation and viability effects form a good starting point for the analysis of many networks. PMID:17395721

  9. Miniature Reversal Electron-Attachment Detector

    NASA Technical Reports Server (NTRS)

    Chutjian, Ara

    1994-01-01

    Miniature reversal electron-attachment detector (miniREAD) enables direct injection of air or vapor at atmospheric pressure from monitored area into mass-spectrometric instrument to detect explosives, narcotics, or other substances, vapors of which suspected of being present in low concentrations. In comparison with older reversal electron-attachment detector, miniREAD simpler in design; more rugged; and easier to build, repair, and maintain. In addition, probably more sensitive.

  10. Attachment device for an inflatable protective cushion

    DOEpatents

    Nelsen, James M.; Luna, Daniel A.; Gwinn, Kenneth W.

    1997-01-01

    An inflatable cushion assembly for use with an inflator comprises an inflatable cushion having an inner surface, outer surface, and at least one protrusion extending from one of the inner or outer surfaces. The inflatable cushion defines an opening between the inner surface and the outer surface for receiving the inflator. An attachment member contacts the one of the inner or outer surfaces adjacent the opening and includes a groove for receiving the protrusion, the attachment member securing the inflator within the opening.

  11. Attachment device for an inflatable protective cushion

    DOEpatents

    Nelsen, James M.; Luna, Daniel A.; Gwinn, Kenneth W.

    1998-01-01

    An inflatable cushion assembly for use with an inflator comprises an inflatable cushion having an inner surface, outer surface, and at least one protrusion extending from one of the inner or outer surfaces. The inflatable cushion defines an opening between the inner surface and the outer surface for receiving the inflator. An attachment member contacts the one of the inner or outer surfaces adjacent the opening and includes a groove for receiving the protrusion, the attachment member securing the inflator within the opening.

  12. Thermal electron attachment to SO3

    SciTech Connect

    Miller, T.M.; Viggiano, A.A.; Arnold, S.T.; Jayne, J.T.

    1995-04-15

    The rate constant for electron attachment to SO3 is 3 + or - 1 x 10(exp-9) cu cm/s at 300 K, measured in helium gas at pressures from 53 to 160 Pa (0.4 to 1.2 torr). The sole product of attachment is SO3(-) under these conditions. The same rate constant and ionic product were obtained at 400 and 505 K. The measurements were carried out using a flowing-afterglow Langmuir-probe apparatus.

  13. Thermal electron attachment to SO3

    NASA Astrophysics Data System (ADS)

    Miller, Thomas M.; Viggiano, A. A.; Arnold, Susan T.; Jayne, John T.

    1995-04-01

    The rate constant for electron attachment to SO3 is 3±1×10-9 cm3 s-1 at 300 K, measured in helium gas at pressures from 53 to 160 Pa (0.4 to 1.2 torr). The sole product of attachment is SO-3 under these conditions. The same rate constant and ionic product were obtained at 400 and 505 K. The measurements were carried out using a flowing-afterglow Langmuir-probe apparatus.

  14. Attachment Stimulates Exopolysaccharide Synthesis by a Bacterium

    SciTech Connect

    Vandevivere, P.; Kirchman, D. L.

    1993-07-28

    Addition of sand to shake-flask cultures seemed to induce exopolymer synthesis by a number of subsurface bacterial isolates, as revealed by optical microscopy. Several additional lines of evidence indicate that exopolymer production by attached cells (in continuous-flow, sand-packed columns) was greater than by their free-living counterparts. The mechanism by which attachment stimulated exopolymer synthesis did not involve changes of the specific growth rate, growth stage, or limiting nutrient.

  15. Composite materials with metal oxide attached to lead chalcogenide nanocrystal quantum dots with linkers

    DOEpatents

    Fuke, Nobuhiro; Koposov, Alexey Y; Sykora, Milan; Hoch, Laura

    2014-12-16

    Composite materials useful for devices such as photoelectrochemical solar cells include a substrate, a metal oxide film on the substrate, nanocrystalline quantum dots (NQDs) of lead sulfide, lead selenide, and lead telluride, and linkers that attach the NQDs to the metal oxide film. Suitable linkers preserve the 1s absorption peak of the NQDs. A suitable linker has a general structure A-B-C where A is a chemical group adapted for binding to a MO.sub.x and C is a chemical group adapted for binding to a NQD and B is a divalent, rigid, or semi-rigid organic spacer moiety. Other linkers that preserve the 1s absorption peak may also be used.

  16. Statistical mechanical model of gas adsorption in porous crystals with dynamic moieties

    PubMed Central

    Braun, Efrem; Carraro, Carlo; Smit, Berend

    2017-01-01

    Some nanoporous, crystalline materials possess dynamic constituents, for example, rotatable moieties. These moieties can undergo a conformation change in response to the adsorption of guest molecules, which qualitatively impacts adsorption behavior. We pose and solve a statistical mechanical model of gas adsorption in a porous crystal whose cages share a common ligand that can adopt two distinct rotational conformations. Guest molecules incentivize the ligands to adopt a different rotational configuration than maintained in the empty host. Our model captures inflections, steps, and hysteresis that can arise in the adsorption isotherm as a signature of the rotating ligands. The insights disclosed by our simple model contribute a more intimate understanding of the response and consequence of rotating ligands integrated into porous materials to harness them for gas storage and separations, chemical sensing, drug delivery, catalysis, and nanoscale devices. Particularly, our model reveals design strategies to exploit these moving constituents and engineer improved adsorbents with intrinsic thermal management for pressure-swing adsorption processes. PMID:28049851

  17. Influence of PPh₃ moiety in the anticancer activity of new organometallic ruthenium complexes.

    PubMed

    Sáez, Rubén; Lorenzo, Julia; Prieto, Ma Jose; Font-Bardia, Mercè; Calvet, Teresa; Omeñaca, Nuria; Vilaseca, Marta; Moreno, Virtudes

    2014-07-01

    The effect of the PPh3 group in the antitumor activity of some new organometallic ruthenium(II) complexes has been investigated. Several complexes of the type [Ru((II))(Cl)(PPh3)(Lig-N)], [Ru((II))(Cl)2(Lig-N)] (where Lig-N=pyridine derivate) and [Ru((II))(Cl)(PPh3)2], have been synthesized and characterized. A noticeable increment of the antitumor activity and cytotoxicity of the complexes due to the presence of PPh3 moiety has also been demonstrated, affording IC50 values of 5.2 μM in HL-60 tumor cell lines. Atomic force microscopy, circular dichroism and electrophoresis experiments have proved that these complexes can bind DNA resulting in a distortion of both secondary and tertiary structures. Ethidium bromide displacement fluorescence spectroscopy studies and viscosity measurements support that the presence of PPh3 group induces intercalation interactions with DNA. Indeed, crystallographic analysis, suggest that intra-molecular π-π interactions could be involved in the intercalation within DNA base pairs. Furthermore, high performance liquid chromatography mass spectrometry (HPLC-MS) studies have confirmed a strong interaction between ruthenium complexes and proteins (ubiquitin and potato carboxypeptidase inhibitor - PCI) including slower kinetics due to the presence of PPh3 moiety, which could have an important role in detoxification mechanism and others. Finally, ion mobility mass spectrometry (IMMS) experiments have proved that there is no significant change in the gas phase structural conformation of the proteins owing to their bonding to ruthenium complexes.

  18. Dynamic scaffold of chiral binaphthol derivatives with the alkynylplatinum(II) terpyridine moiety

    PubMed Central

    Leung, Sammual Yu-Lut; Lam, Wai Han; Yam, Vivian Wing-Wah

    2013-01-01

    Platinum(II)-containing complexes with inherently chiral binaphthol derivatives display a versatile scaffold between random coils and single-turn helical strands, in which the conformational transition is controlled by the Pt···Pt and π−π interactions of alkynylplatinum(II) terpyridine moiety upon solvent and temperature modulation. The bisignate Cotton effect in the circular dichroism spectra is indicative of the cooperative transformation from random coil state to a compact single-turn M- or P- helix. More importantly, as revealed by the appearance of new UV-vis absorption and emission bands during conformational change, the self-assembly of the platinum(II)-containing complex into a helical structure is assisted by the metal···metal and π−π interactions of the alkynylplatinum(II) terpyridine moieties. The folded structure with stabilization via metal···metal and π−π interactions has been supported by density functional theory calculations, which provide insights into the folded geometry of these kind of metallo-foldamers. PMID:23542379

  19. Personality and Attachment in Transsexual Adults.

    PubMed

    Lingiardi, Vittorio; Giovanardi, Guido; Fortunato, Alexandro; Nassisi, Valentina; Speranza, Anna Maria

    2017-02-16

    The main aim of this study was to investigate the associations between personality features and attachment patterns in transsexual adults. We explored mental representations of attachment, assessed personality traits, and possible personality disorders. Forty-four individuals diagnosed with gender identity disorder (now gender dysphoria), 28 male-to-female and 16 female-to-male, were evaluated using the Shedler-Westen assessment procedure-200 (SWAP-200) to assess personality traits and disorders; the adult attachment interview was used to evaluate their attachment state-of-mind. With respect to attachment, our sample differed both from normative samples because of the high percentage of disorganized states of mind (50% of the sample), and from clinical samples for the conspicuous percentage of secure states of mind (37%). Furthermore, we found that only 16% of our sample presented a personality disorder, while 50% showed a high level of functioning according to the SWAP-200 scales. In order to find latent subgroups that shared personality characteristics, we performed a Q-factor analysis. Three personality clusters then emerged: Healthy Functioning (54% of the sample); Depressive/Introverted (32%) and Histrionic/Extroverted (14%). These data indicate that in terms of personality and attachment, GD individuals are a heterogeneous sample and show articulate and diverse types with regard to these constructs.

  20. 30 CFR 77.1436 - Drum end attachment.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... Hoisting Wire Ropes § 77.1436 Drum end attachment. (a) For drum end attachment, wire rope shall be attached... professional engineer. (b) A minimum of three full turns of wire rope shall be on the drum when the rope...

  1. 30 CFR 77.1436 - Drum end attachment.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... Hoisting Wire Ropes § 77.1436 Drum end attachment. (a) For drum end attachment, wire rope shall be attached... professional engineer. (b) A minimum of three full turns of wire rope shall be on the drum when the rope...

  2. 30 CFR 77.1436 - Drum end attachment.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... Hoisting Wire Ropes § 77.1436 Drum end attachment. (a) For drum end attachment, wire rope shall be attached... professional engineer. (b) A minimum of three full turns of wire rope shall be on the drum when the rope...

  3. 30 CFR 77.1436 - Drum end attachment.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... Hoisting Wire Ropes § 77.1436 Drum end attachment. (a) For drum end attachment, wire rope shall be attached... professional engineer. (b) A minimum of three full turns of wire rope shall be on the drum when the rope...

  4. 30 CFR 77.1436 - Drum end attachment.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Hoisting Wire Ropes § 77.1436 Drum end attachment. (a) For drum end attachment, wire rope shall be attached... professional engineer. (b) A minimum of three full turns of wire rope shall be on the drum when the rope...

  5. 48 CFR 204.7105 - Contract exhibits and attachments.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... attachments. 204.7105 Section 204.7105 Federal Acquisition Regulations System DEFENSE ACQUISITION REGULATIONS... 204.7105 Contract exhibits and attachments. Follow the procedures at PGI 204.7105 for use and numbering of contract exhibits and attachments....

  6. Electron attachment induced proton transfer in a DNA nucleoside pair: 2'-deoxyguanosine-2'-deoxycytidine

    NASA Astrophysics Data System (ADS)

    Gu, Jiande; Xie, Yaoming; Schaefer, Henry F.

    2007-10-01

    To elucidate electron attachment induced damage in the DNA double helix, electron attachment to the 2'-deoxyribonucleoside pair dG:dC has been studied with the reliably calibrated B3LYP /DZP++ theoretical approach. The exploration of the potential energy surface of the neutral and anionic dG:dC pairs predicts a positive electron affinity for dG:dC [0.83eV for adiabatic electron affinity (EAad) and 0.16eV for vertical electron affinity (VEA)]. The substantial increases in the electron affinity of dG:dC (by 0.50eV for EAad and 0.23eV for VEA) compared to those of the dC nucleoside suggest that electron attachment to DNA double helices should be energetically favored with respect to the single strands. Most importantly, electron attachment to the dC moiety in the dG:dC pair is found to be able to trigger the proton transfer in the dG :dC-• pair, surprisingly resulting in the lower energy distonic anionic complex d(G-H )-:d(C+H)•. The negative charge for the latter system is located on the base of dC in the dG :dC-• pair, while it is transferred to d(G-H) in d(G-H )-:d(C+H)•, accompanied by the proton transfer from N1(dG) to N3(dC). The low energy barrier (2.4kcal/mol) for proton transfer from dG to dC-• suggests that the distonic d(G-H )-:d(C+H)• pair should be one of the important intermediates in the process of electron attachment to DNA double helices. The formation of the neutral nucleoside radical d(C +H)• is predicted to be the direct result of electron attachment to the DNA double helices. Since the neutral radical d(C +H)• nucleotide is the key element in the formation of this DNA lesion, electron attachment might be one of the important factors that trigger the formation of abasic sites in DNA double helices.

  7. Electron attachment induced proton transfer in a DNA nucleoside pair: 2'-deoxyguanosine-2'-deoxycytidine.

    PubMed

    Gu, Jiande; Xie, Yaoming; Schaefer, Henry F

    2007-10-21

    To elucidate electron attachment induced damage in the DNA double helix, electron attachment to the 2'-deoxyribonucleoside pair dG:dC has been studied with the reliably calibrated B3LYP/DZP++ theoretical approach. The exploration of the potential energy surface of the neutral and anionic dG:dC pairs predicts a positive electron affinity for dG:dC [0.83 eV for adiabatic electron affinity (EAad) and 0.16 eV for vertical electron affinity (VEA)]. The substantial increases in the electron affinity of dG:dC (by 0.50 eV for EAad and 0.23 eV for VEA) compared to those of the dC nucleoside suggest that electron attachment to DNA double helices should be energetically favored with respect to the single strands. Most importantly, electron attachment to the dC moiety in the dG:dC pair is found to be able to trigger the proton transfer in the dG:dC- pair, surprisingly resulting in the lower energy distonic anionic complex d(G-H)-:d(C+H).. The negative charge for the latter system is located on the base of dC in the dG:dC- pair, while it is transferred to d(G-H) in d(G-H)-:d(C+H)., accompanied by the proton transfer from N1(dG) to N3(dC). The low energy barrier (2.4 kcal/mol) for proton transfer from dG to dC- suggests that the distonic d(G-H)-:d(C+H). pair should be one of the important intermediates in the process of electron attachment to DNA double helices. The formation of the neutral nucleoside radical d(C+H). is predicted to be the direct result of electron attachment to the DNA double helices. Since the neutral radical d(C+H). nucleotide is the key element in the formation of this DNA lesion, electron attachment might be one of the important factors that trigger the formation of abasic sites in DNA double helices.

  8. Allergenicity of Hev b 13, a major esterase allergen in natural rubber latex (Hevea brasiliensis) allergy, does not only depend on its carbohydrate moiety.

    PubMed

    Rougé, Pierre; Culerrier, Raphaël; Campistron, Marion; Granier, Claude; Bienvenu, Françoise; Bienvenu, Jacques; Didier, Alain; Barre, Annick

    2010-01-01

    The three-dimensional model built for the major latex allergen Hev b 13 consists of the typical organization of plant esterases made of a central bundle of five parallel beta-strands surrounded by five alpha-helices associated to two shorter alpha-helical segments. Up to 12 sets of sequential IgE-binding peptides were identified in SPOT experiments along the amino acid sequence of Hev b 13. They correspond in fact to eight IgE-binding epitopic stretches exposed on the surface of the allergen. With the exception of epitope #5, all other epitopes contain charged residues. Epitope #8 contains the 3rd putative N-glycosylation site of Hev b 13 and should consist of a glycotope, whereas all other identified IgE-binding areas occur outside the two remaining putative N-glycosylation sites. Accordingly, the allergenicity of Hev b 13 does not primarily depends on its carbohydrate moiety.

  9. Functional group dependent dissociative electron attachment to simple organic molecules

    NASA Astrophysics Data System (ADS)

    Prabhudesai, Vaibhav S.; Nandi, Dhananjay; Kelkar, Aditya H.; Krishnakumar, E.

    2008-04-01

    Dissociative electron attachment (DEA) cross sections for simple organic molecules, namely, acetic acid, propanoic acid, methanol, ethanol, and n-propyl amine are measured in a crossed beam experiment. We find that the H- ion formation is the dominant channel of DEA for these molecules and takes place at relatively higher energies (>4eV) through the core excited resonances. Comparison of the cross sections of the H- channel from these molecules with those from NH3, H2O, and CH4 shows the presence of functional group dependence in the DEA process. We analyze this new phenomenon in the context of the results reported on other organic molecules. This discovery of functional group dependence has important implications such as control in electron induced chemistry and understanding radiation induced damage in biological systems.

  10. Cross-structural priming: prepositional phrase attachment primes relative clause attachment.

    PubMed

    Loncke, Maaike; Van Laere, Sébastien M J; Desmet, Timothy

    2011-01-01

    In this paper we show that attachment height (high vs. low attachment) of a modifier to a complex noun phrase (CNP; e.g., "the servant of the actress"), can be primed between dissimilar syntactic structures. In a sentence completion experiment, we found that the attachment height of a prepositional phrase (PP) in the prime sentence primed the attachment height of a relative clause (RC) in the target sentence. This cross-structural priming effect cannot be explained in terms of the priming of specific phrase-structure rules or even sequences of specific phrase-structure rules (Scheepers, 2003), because the attachment of a PP to a CNP is generated by a different phrase-structure rule than the attachment of an RC. However, the present data suggest that the location at which the RC is attached to the CNP is mentally represented, independent of the specific phrase-structure rule that is attached, or by extension, that the abstract hierarchical configuration of the full CNP and the attached RC is represented (Desmet & Declercq, 2006). This is the first demonstration of a cross-structural priming effect that cannot be captured by phrase-structure rules.

  11. Chemical attachment of magnetic nanoparticles through ``click chemistry''

    NASA Astrophysics Data System (ADS)

    Liu, Yue; Teplyakov, Andrew Y.; Hadjipanayis, George C.

    2013-03-01

    Iron nanoparticles were used as a test system to explore the functionalization and attachment of magnetic nanoparticles with two different functionalities through ``click chemistry.'' Two different samples of iron nanoparticles were modified with 5-azidopentanoic acid and with 5-hexynoic acid, respectively. This modification was followed by click chemistry to change the morphology of agglomeration. A combination of density functional theory calculations, Fourier-transform infrared spectroscopy, and X-ray photoelectron spectroscopy was used to monitor each step of the process. Spectroscopies confirmed the success and completion of click reaction. Scanning electron microscopy images showed the change in size and morphology of the iron nanoparticles before and after click chemistry. Vibrating sample magnetometer study showed the majority of the magnetic properties were retained following functionalization and click reaction. Exploring similar approach for two types of materials with functionalization and attachment of hard magnetic materials and soft magnetic materials will be presented based on our initial studies of SmCo nanoparticles in a combination with iron nanoparticles. Work supported by DOE ARPA-E.

  12. Production of a complement inhibitor possessing sialyl Lewis X moieties by in vitro glycosylation technology.

    PubMed

    Thomas, Lawrence J; Panneerselvam, Krishnasamy; Beattie, David T; Picard, Michele D; Xu, Bi; Rittershaus, Charles W; Marsh, Henry C; Hammond, Russell A; Qian, Jun; Stevenson, Tom; Zopf, David; Bayer, Robert J

    2004-10-01

    Recombinant soluble human complement receptor type 1 (sCR1) is a highly glycosylated glycoprotein intended for use as a drug to treat ischemia-reperfusion injury and other complement-mediated diseases and injuries. sCR1-sLe(x) produced in the FT-VI-expressing mutant CHO cell line LEC11 exists as a heterogeneous mixture of glycoforms, a fraction of which include structures with one or more antennae terminated by the sialyl Lewis X (sLe(x)) [Neu5Acalpha2-3Galbeta1-4(Fucalpha1-3)GlcNAc]) epitope. Such multivalent presentation of sLe(x) was shown previously to effectively target sCR1 to activated endothelial cells expressing E-selectin. Here, we describe the use of the soluble, recombinant alpha2-3 sialyltransferase ST3Gal-III and the alpha1-3 fucosyltransferase FT-VI in vitro to introduce sLe(x) moieties onto the N-glycan chains of sCR1 overexpressed in standard CHO cell lines. The product (sCR1-S/F) of these in vitro enzymatic glycan remodeling reactions performed at the 10-g scale has approximately 14 N-glycan chains per sCR1 molecule, comprised of biantennary (90%), triantennary (8.5%), and tetraantennary (1.5%) structures, nearly all of whose antennae terminate with sLe(x) moieties. sCR1-S/F retained complement inhibitory activity and, in comparison with sCR1-sLe(x) produced in the LEC11 cell line, contained twice the number of sLe(x) moieties per mole glycoprotein, exhibited a twofold increase in area under the intravenous clearance curve in a rat pharmacokinetic model, and exhibited a 10-fold increase in affinity for E-selectin in an in vitro binding assay. These results demonstrate that in vitro glycosylation of the sCR1 drug product reduces heterogeneity of the glycan profile, improves pharmacokinetics, and enhances carbohydrate-mediated binding to E-selectin.

  13. Modulating weak intramolecular interactions through the formation of beryllium bonds: complexes between squaric acid and BeH2.

    PubMed

    Montero-Campillo, M Merced; Lamsabhi, Al Mokhtar; Mó, Otilia; Yáñez, Manuel

    2013-07-01

    The electronic structure of the two most stable isomers of squaric acid and their complexes with BeH2 were investigated at the B3LYP/6-311 + G(3df,2p)// B3LYP/6-31 + G(d,p) level of theory. Squaric acid forms rather strong beryllium bonds with BeH2, with binding energies of the order of 60 kJ mol(-1). The preferential sites for BeH2 attachment are the carbonyl oxygen atoms, but the global minima of the potential energy surfaces of both EZ and ZZ isomers are extra-stabilized through the formation of a BeH···HO dihydrogen bond. More importantly, analysis of the electron density of these complexes shows the existence of significant cooperative effects between the beryllium bond and the dihydrogen bond, with both becoming significantly reinforced. The charge transfer involved in the formation of the beryllium bond induces a significant electron density redistribution within the squaric acid subunit, affecting not only the carbonyl group interacting with the BeH2 moiety but significantly increasing the electron delocalization within the four membered ring. Accordingly the intrinsic properties of squaric acid become perturbed, as reflected in its ability to self-associate.

  14. Photochemical Production and Behavior of Hydroperoxyacids in Heterotrophic Bacteria Attached to Senescent Phytoplanktonic Cells

    PubMed Central

    Petit, Morgan; Sempéré, Richard; Vaultier, Frédéric; Rontani, Jean-François

    2013-01-01

    The photooxidation of cellular monounsaturated fatty acids was investigated in senescent phytoplanktonic cells (Emiliania huxleyi) and in their attached bacteria under laboratory controlled conditions. Our results indicated that UV-visible irradiation of phytodetritus induced the photooxidation of oleic (produced by phytoplankton and bacteria) and cis-vaccenic (specifically produced by bacteria) acids. These experiments confirmed the involvement of a substantial singlet oxygen transfer from senescent phytoplanktonic cells to attached bacteria, and revealed a significant correlation between the concentration of chlorophyll, a photosensitizer, in the phytodetritus and the photodegradation state of bacteria. Hydroperoxyacids (fatty acid photoproducts) appeared to be quickly degraded to ketoacids and hydroxyacids in bacteria and in phytoplanktonic cells. This degradation involves homolytic cleavage (most likely induced by UV and/or transition metal ions) and peroxygenase activity (yielding epoxy acids). PMID:23736689

  15. Overview for Attached Payload Accommodations and Environments

    NASA Technical Reports Server (NTRS)

    Schaffer, Craig; Cook, Gene; Nabizadeh, Rodney; Phillion, James

    2007-01-01

    External payload accommodations are provided at attach sites on the U.S provided ELC, U.S. Truss, the Japanese Experiment Module Exposed Facility (JEM EF) and the Columbus EPF (External Payload Facilities). The Integrated Truss Segment (ITS) provides the backbone structure for the ISS. It attaches the solar and thermal control arrays to the rest of the complex, and houses cable distribution trays Extravehicular Activity (EVA) support equipment such as handholds and lighting; and providing for Extravehicular Robotic (EVR) accommodations using the Mobile Servicing System (MSS). It also provides logistics and maintenance, and payload attachment sites. The attachment sites accommodate logistics and maintenance and payloads carriers, zenith and nadir. The JEM-EF, a back porch-like attachment to the JEM Pressurized Module, accommodates up to eight payloads, which can be serviced by the crew via the JEM PM's airlock and dedicated robotic arm. The Columbus-EPF is another porch-like platform that can accommodate two zenith and two nadir looking payloads.

  16. Ultrasonic device for measuring periodontal attachment levels

    NASA Astrophysics Data System (ADS)

    Lynch, J. E.; Hinders, M. K.

    2002-07-01

    Periodontal disease is manifested clinically by a degradation of the ligament that attaches the tooth to the bone. The most widely used diagnostic tool for assessment of periodontal diseases, measurement of periodontal attachment loss with a manual probe, may overestimate attachment loss by as much as 2 mm in untreated sites, while underestimating attachment loss by an even greater margin following treatment. Manual probing is also invasive, which causes patient discomfort. This work describes the development and testing of an ultrasonographic periodontal probe designed to replace manual probing. It uses a thin stream of water to project an ultrasonic beam into the periodontal pocket, and then measures echoes off features within the pocket. To do so, the ultrasonic beam must be narrowed from 2 (the diameter of the transducer) to 0.5 mm (the approximate width of the periodontal pocket at the gingival margin). The proper choice of transducer frequency, the proper method for controlling water flow from the probe, and a model for interpreting these echoes are also addressed. Initial results indicate that the device measures echoes from the hard tissue of the tooth surface, and that the periodontal attachment level can be inferred from these echoes.

  17. ISS truss attached payload accommodations overview

    NASA Astrophysics Data System (ADS)

    Youmans, Janella S.; Olson, Michael F.; Foster, Mark A.; Watkins, Barbara S.

    1999-01-01

    One of the defining features of the International Space Station (ISS) is its capacity to accommodate long-term science in the external environment of space. The large truss structure spanning the vehicle is designed to support core system equipment such as solar arrays, thermal radiators, and the pressurized module structures. In addition to supporting core systems, the truss structure also accommodates four attached payload facilities and two logistics carriers. This paper focuses on the capabilities of the ISS in accommodating externally attached science payloads, defines the locations where experiments can be conducted, explains the environment wherein typical experiments will be performed, and identifies the payload interfaces and access to resources such as power and data. The paper will also summarize the robotic accommodations which will support attached payloads and describes typical procedures for installation of the payloads onto the sites. Finally, the paper will provide a summary description of the attach sites on the NASDA Exposed Facility and the potential for use of alternative attach sites on the ISS.

  18. Mother-infant attachment in adoptive families.

    PubMed

    Singer, L M; Brodzinsky, D M; Ramsay, D; Steir, M; Waters, E

    1985-12-01

    Data from 2 separate samples using the Strange Situation paradigm were combined to assess the quality of attachment relationships in adoptive and nonadoptive mother-infant pairs. Infants were between 13 and 18 months at the time of observation. Results indicated no differences in mother-infant attachment between nonadopted and intraracial adopted subjects or between intraracial and interracial adopted subjects. Interracial adoptive mother-infant pairs did show a higher incidence of insecure attachment in comparison to nonadoptive pairs. Mothers of interracial adopted infants also were less comfortable having others care for their babies and perceived less emotional support from extended family and friends for their decision to adopt a child prior to the actual adoption than did other mothers. No relation was found, however, between quality of mother-infant attachment and either perceived social support, infant developmental quotient, infant temperament, number of foster homes experienced by the infant, or infant's age at the time of adoption placement. It was suggested that the higher incidence of psychological problems found among adoptees in middle childhood and adolescence cannot be explained in terms of insecure attachment relationships during the infancy years.

  19. Surface-attachment sequence in Vibrio Cholerae

    NASA Astrophysics Data System (ADS)

    Utada, Andrew; Gibiansky, Maxsim; Wong, Gerard

    2013-03-01

    Vibrio cholerae is a gram-negative bacterium that causes the human disease cholera. It is found natively in brackish costal waters in temperate climates, where it attaches to the surfaces of a variety of different aquatic life. V. cholerae has a single polar flagellum making it highly motile, as well as a number of different pili types, enabling it to attach to both biotic and abiotic surfaces. Using in-house built tracking software we track all surface-attaching bacteria from high-speed movies to examine the early-time attachment profile of v. cholerae onto a smooth glass surface. Similar to previous work, we observe right-handed circular swimming trajectories near surfaces; however, in addition we see a host of distinct motility mechanisms that enable rapid exploration of the surface before forming a more permanent attachment. Using isogenic mutants we show that the motility mechanisms observed are due to a complex combination of hydrodynamics and pili-surface interactions. Lauga, E., DiLuzio, W. R., Whitesides, G. M., Stone, H. A. Biophys. J. 90, 400 (2006).

  20. Temporal evolution of Townsend's attached eddies

    NASA Astrophysics Data System (ADS)

    Lozano-Duran, Adrian; Jimenez, Javier

    2013-11-01

    The temporal evolution of the eddies responsible for the momentum transfer in a turbulent channel are studied using time-resolved DNS data at Reτ = 4000 . The eddies are identified as connected regions of intense tangential Reynolds stress, and tracked in time. Once their evolutions are properly organized, they provide the necessary information to characterize eddies from birth to death. Eddies are born at all distances from the wall, although with higher probability near it, where the shear is strongest. Most of them stay small and do not last for long times. However, there is a family of eddies that become large enough to get attached to the wall while they reach into the logarithmic layer. They can be considered the best candidates for Townsend's attached eddies found until now. They are geometrically self-similar, with sizes and lifetimes proportional to their distance from the wall. Eddies associated with ejections move away from the wall with dy / dt =uτ , and their base attaches very fast at the beginning of their lives. Conversely, sweeps move towards the wall at -uτ , and attach later. In both cases, they remain attached for 2 / 3 of their lives. In the streamwise direction, eddies are advected and sheared by the local mean velocity. Funded by ERC, CICYT and Spanish Ministry of Science.

  1. Highs and Lows in English Attachment.

    PubMed

    Grillo, Nino; Costa, João; Fernandes, Bruno; Santi, Andrea

    2015-11-01

    Grillo and Costa (2014) claim that Relative-Clause attachment ambiguity resolution is largely dependent on whether or not a Pseudo-Relative interpretation is available. Data from Italian, and other languages allowing Pseudo-Relatives, support this hypothesis. Pseudo-Relative availability, however, covaries with the semantics of the main predicate (e.g., perceptual vs. stative). Experiment 1 assesses whether this predicate distinction alone can account for prior attachment results by testing it with a language that disallows Pseudo-Relatives (i.e. English). Low Attachment was found independent of Predicate-Type. Predicate-Type did however have a minor modulatory role. Experiment 2 shows that English, traditionally classified as a Low Attachment language, can demonstrate High Attachment with sentences globally ambiguous between a Small-Clause and a reduced Relative-Clause interpretation. These results support a grammatical account of previous effects and provide novel evidence for the parser's preference of a Small-Clause over a Restrictive interpretation, crosslinguistically.

  2. Photoinitiated electron transfer in multichromophoric species: Synthetic tetrads and pentads featuring diquinone moieties

    SciTech Connect

    Not Available

    1992-04-30

    This project involves the design, synthesis and photophysical study of complex molecular systems engineered to achieve long lived charge separated states by a biomimetic, photoinitiated multistep electron transfer process. The use of these artificial systems to investigate different electron and energy transfer strategies will allow the evolution of more efficient molecular devices for the gathering of light energy and its transformation into chemical potential energy. The three major aspects of the work emphasized in the initial proposal are: design and synthesis of molecular devices incorporating new quinone moieties, synthesis and spectroscopic studies of molecular tetrads and pentads featuring modified porphyrin-diquinone linkages, and new photochemical and photophysical investigations of tetrads and pentads, including the development of methods for harvesting the energy stored in long-lived charge separated states.

  3. Nitric oxide donor beta2-agonists: furoxan derivatives containing the fenoterol moiety and related furazans.

    PubMed

    Buonsanti, M Federica; Bertinaria, Massimo; Stilo, Antonella Di; Cena, Clara; Fruttero, Roberta; Gasco, Alberto

    2007-10-04

    The structure of fenoterol, a beta2-adrenoceptor agonist used in therapy, has been joined with furoxan NO-donor moieties to give new NO-donor beta2-agonists. The furazan analogues, devoid of the property to release NO, were also synthesized for comparison. All the compounds retained beta2-agonistic activity at micromolar or submicromolar concentration when tested on guinea pig tracheal rings precontracted with carbachol. Among the furoxan derivatives, the NO contribution to trachea relaxation was evident with product 15b at micromolar concentrations. All the new NO-donor hybrids were able to dilate rat aortic strips precontracted with phenylephrine. Both furoxan and furazan derivatives displayed antioxidant activity greater than that of fenoterol.

  4. Design, Synthesis, and Structure-Activity Relationship of New Pyrimidinamine Derivatives Containing an Aryloxy Pyridine Moiety.

    PubMed

    Guan, Aiying; Liu, Changling; Chen, Wei; Yang, Fan; Xie, Yong; Zhang, Jinbo; Li, Zhinian; Wang, Mingan

    2017-02-15

    The pyrimidinamine diflumetorim is an ideal template for the discovery of agrochemical lead compounds due to its unique mode of action, novel chemical structure, and lack of reported resistance. To develop a new pyrimidinamine fungicide effective against cucumber downy mildew (CDM), a series of new pyrimidinamine derivatives containing an aryloxy pyridine moiety were designed and synthesized by employing the recently reported intermediate derivatization method (IDM). The structures of all compounds were identified by (1)H NMR, elemental analyses, HRMS, and X-ray diffraction. Bioassays demonstrated that some of the title compounds exhibited excellent fungicidal activities against CDM. Compound 9 gave the best activity (EC50 = 0.19 mg/L), which is significantly better than the commercial fungicides diflumetorim, flumorph, and cyazofamid. The relationship between structure and fungicidal activity of the synthesized pyrimidinamines was explored. The study showed that compound 9 is a promising fungicide candidate for further development.

  5. Dendrimers incorporating benzenesulfonamide moieties strongly inhibit carbonic anhydrase isoforms I-XIV.

    PubMed

    Carta, Fabrizio; Osman, Sameh M; Vullo, Daniela; AlOthman, Zeid; Supuran, Claudiu T

    2015-06-21

    As extension of our previous study herein we report a comprehensive investigation of poly(amidoamine) (PAMAM) dendrimers as modulators of the human carbonic anhydrase (hCA, EC 4.2.1.1) isoforms I-XIV. Interestingly inhibitory activity was observed for the non-functionalized dendrimers against the hCA I, VII, IX, XII and XIV isoforms, whereas activation properties were reported only for the cytosolic abundant hCA II. Highly efficient inhibitory action against many isoforms having medicinal chemistry applications, such as hCA II, V, VII, IX, XII and XIV, was observed for the PAMAM functionalized counterparts bearing 4, 8, 16 and 32 benzenesulfonamide moieties. Possible applications of dendrimer-CA inhibitors as therapeutic/diagnostic agents are envisaged.

  6. Zwitterionic Moieties from the Huisgen Reaction-A Case Study with Amphiphilic Dendritic Assemblies

    PubMed Central

    Ramireddy, Rajasekhar R.; Subrahmanyam, Ayyagari V.

    2014-01-01

    Supramolecular nano-assemblies that reduce non-specific interactions with biological macromolecules, such as proteins, are of great importance for various biological applications. Recently, zwitterionic materials have been shown to reduce non-specific interactions with biomolecules, owing both to their charge neutrality and their ability to form strong hydration layer around zwitterions via electrostatic interactions. In this article, we present new triazole-based zwitterionic moieties that are incorporated as the hydrophilic functionalities in facially amphiphilic dendrons. The amphiphilic zwitterionic dendrons spontaneously self-assemble in aqueous solutions forming micelle-type aggregates, which are confirmed by DLS, TEM, and fluorescence techniques. We also compare the structural and functional characteristics of the zwitterionic dendrons with the corresponding charge-neutral PEG-based dendrons and anionic carboxylate-based dendrons. Surface charge measurements, temperature sensitivity and evaluation of interactions of these assemblies with proteins form the bases for these comparisons. PMID:24151036

  7. Synthesis and Biological Investigation of some Novel Sulfonamide and Amide Derivatives Containing Coumarin Moieties

    PubMed Central

    Saeedi, Mina; Goli, Fereshteh; Mahdavi, Mohammad; Dehghan, Gholamreza; Faramarzi, Mohammad Ali; Foroumadi, Alireza; Shafiee, Abbas

    2014-01-01

    New sulfonamide and amide derivatives containing coumarin moieties; oxo-2H-chromen-sulfamoylphenylacetamides and oxo-2H-chromen-arylacetamides were synthesized starting from diverse 2-chloroacetamide derivatives and a wide range of coumarins. The structures of compounds were elucidated by IR and NMR spectra and also analytical elemental analysis. In the next step, the above mentioned compounds were screened for their antimicrobial and antioxidant activities. Their antimicrobial activity was assigned using the conventional agar dilution method and the antioxidant activity was assessed using two methods, 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging method and ferric reducing antioxidant power (FRAP) assay. Although the compounds showed no remarkable antimicrobial activities, most of them exhibited good antioxidant activities. Compounds 5b showed the most potent DPPH activity, whereas 8c was the most efficient compound in FRAP assay. PMID:25276188

  8. Discovery of novel diaryl urea derivatives bearing a triazole moiety as potential antitumor agents.

    PubMed

    Qin, Mingze; Yan, Shuang; Wang, Lei; Zhang, Haotian; Zhao, Yanfang; Wu, Shasha; Wu, Di; Gong, Ping

    2016-06-10

    Herein, we report a novel series of diaryl urea derivatives bearing a triazole moiety, from which potent antitumor agents have been identified. With a modified triazole, most compounds showed high level activity in both cellular and enzymatic assays, accompanied with a suitable ClogD7.4 value. The most active compound, 13i, effectively suppressed proliferation of HT-29, H460 and MDA-MB-231 cancer cells, with IC50 values of 0.90, 0.85 and 1.54 μM, respectively. Compound 13i also exhibited significant inhibition of tyrosine kinases including c-Kit, RET and FLT3. Furthermore, compound 13i could obviously induce apoptosis of HT-29 cells in a concentration-dependent manner. The study of structure-activity relationships also revealed that a hydrophilic tail at the 4-position of the triazole was crucial for high activity of the compound.

  9. Design and synthesis of potent bradykinin agonists containing a benzothiazepine moiety.

    PubMed

    Amblard, M; Daffix, I; Bedos, P; Bergé, G; Pruneau, D; Paquet, J L; Luccarini, J M; Bélichard, P; Dodey, P; Martinez, J

    1999-10-07

    A bradykinin analogue (H-Arg-Pro-Pro-Gly-Phe-Ser-D-BT-Arg-OH, 3) in which the Pro-Phe dipeptide was replaced by the (3S)[amino]-5-(carbonylmethyl)-2,3-dihydro-1, 5-benzothiazepin-4(5H)-one (D-BT) moiety has been synthesized. The same modification was performed on the potent bradykinin B(2) receptor antagonist HOE 140 (H-D-Arg-Arg-Pro-Hyp-Gly-Thi-Ser-D-Tic-Oic-Arg-OH), in which the -D-Tic-Oic- moiety was replaced by D-BT to yield H-D-Arg-Arg-Pro-Hyp-Gly-Thi-Ser-D-BT-Arg-OH, 1 (JMV1116). These compounds were examined in vitro for their binding affinity toward bradykinin B(1) and B(2) receptors as well as for their ability to interfere with bradykinin-induced contraction of both human umbilical vein and rat uterus. The two compounds 3 and 1 competed with [(3)H]bradykinin binding to the human cloned B(2) receptor giving K(i) values of 13 +/- 2 and 0.7 +/- 0.1 nM, respectively. Unexpectedly, both compounds were full bradykinin B(2) receptor agonists on the human umbilical vein (pD(2) = 6.60 +/- 0.07 for 3 and 6.80 +/- 0.08 for 1) and rat uterus (pD(2) = 7.20 +/- 0.09 for 3 and 7.50 +/- 0.09 for 1) preparations with the same efficacy as bradykinin. In addition 1 induced a concentration-dependent phosphoinositide production in CHO cells expressing the human cloned B(2) receptor. These data provide evidence for a bioactive conformation of bradykinin constrained at the dipeptide Pro-Phe.

  10. An organometallic guide to the chemistry of hydrocarbon moieties on transition metal surfaces

    SciTech Connect

    Zaera, F.

    1995-12-01

    In this review what is known about the chemistry of hydrocarbon molecules on transition metal surfaces will be surveyed. Here the authors discuss the results reported to date on the structure and reactivity of the different types of hydrocarbon moieties that form on transition metal surfaces. One of the goals of this review is to provide an organometallic guide for the possible interactions of hydrocarbons with transition metals with the idea of examining their relation to the corresponding surface chemistry. The authors however limit the review of the organometallic literature to the information relevant to the surface systems, and also narrow the field to cover only molecules with carbon and hydrogen atoms; compounds containing other atoms (O, S, N) will be excluded. The present review is organized in the following manner. First, a brief discussion of the experimental techniques used to characterize both organometallic and surface systems is presented. A discussion of the coordination and structure of the different types of organic moieties, first in organometallic compounds and then on metal surfaces, follows. Here the systems are classified according to the type of bonding between the molecules and the metals. Next, the different elementary steps that such systems can undergo are summarized: C-H and C-C bond-breaking and bond-forming reactions, isomerizations, and others. Again, the chemistry of organometallic compounds is discussed first, and the surface chemistry is presented subsequently. A brief description of a few key nonelementary reactions is also given, including some catalytic processes. Lastly, a brief discussion on the main similarities and differences found so far between surface and organometallic systems, and on possible future directions for this field, is offered.

  11. Attachment and autism: parental attachment representations and relational behaviors in the parent-child dyad.

    PubMed

    Seskin, Lynn; Feliciano, Eileen; Tippy, Gil; Yedloutschnig, Ruby; Sossin, K Mark; Yasik, Anastasia

    2010-10-01

    While attachment research has demonstrated that parents' internal working models of attachment relationships tend to be transmitted to their children, affecting children's developmental trajectories, this study specifically examines associations between adult attachment status and observable parent, child, and dyadic behaviors among children with autism and associated neurodevelopmental disorders of relating and communicating. The Adult Attachment Interview (AAI) was employed to derive parental working models of attachment relationships. The Functional Emotional Assessment Scale (FEAS) was used to determine the quality of relational and functional behaviors in parents and their children. The sample included parents and their 4- to 16-year-old children with autism and associated neurodevelopmental disorders. Hypothesized relationships between AAI classifications and FEAS scores were supported. Significant correlations were found between AAI classification and FEAS scores, indicating that children with autism spectrum disorders whose parents demonstrated secure attachment representations were better able to initiate and respond in two-way pre-symbolic gestural communication; organize two-way social problem-solving communication; and engage in imaginative thinking, symbolic play, and verbal communication. These findings lend support to the relevance of the parent's state of mind pertaining to attachment status to child and parent relational behavior in cases wherein the child has been diagnosed with autism or an associated neurodevelopmental disorder of relating and communicating. A model emerges from these findings of conceptualizing relationships between parental internal models of attachment relationships and parent-child relational and functional levels that may aid in differentiating interventions.

  12. Parent Attachment, Childrearing Behavior, and Child Attachment: Mediated Effects Predicting Preschoolers' Externalizing Behavior

    ERIC Educational Resources Information Center

    Roskam, Isabelle; Meunier, Jean-Christophe; Stievenart, Marie

    2011-01-01

    Attachment theory provides an interesting background for thinking about externalizing behavior (EB) in early childhood and for understanding how parenting influences the child's outcomes. The study examined how attachment and parenting could be combined to explain preschoolers' EB. Data were collected from 117 preschoolers aged from 4 to 6…

  13. Maternal Attachment Representations, Maternal Sensitivity, and the Infant-Mother Attachment Relationship.

    ERIC Educational Resources Information Center

    Pederson, David R.; Gleason, Karin E.; Moran, Greg; Bento, Sandi

    1998-01-01

    Examined the mediating role of maternal sensitivity for the association between maternal attachment representations and the quality of infant-mother attachment. Found that autonomous mothers and mothers in secure relationships were more sensitive at home than nonautonomous mothers and mothers in nonsecure relationships, respectively. Infants in…

  14. Attachment Security and Attentional Breadth toward the Attachment Figure in Middle Childhood

    ERIC Educational Resources Information Center

    Bosmans, Guy; Braet, Caroline; Koster, Ernst; De Raedt, Rudi

    2009-01-01

    To increase our understanding of the cognitive processes involved in internal working models of attachment, this study investigated the relationship between secure attachment and attentional breadth to mother using a dual task design. The content of the cues (mother vs. unfamiliar women) and the duration of the presentation of the cues (34 msec,…

  15. Measuring Lifestyle and Attachment: An Empirical Investigation Linking Individual Psychology and Attachment Theory

    ERIC Educational Resources Information Center

    Peluso, Paul R.; Peluso, Jennifer P.; Buckner, Janine P.; Kern, Roy M.; Curlette, William

    2009-01-01

    P. R. Peluso, J. P. Peluso, J. F. White, and R. M. Kern (2004) reviewed the theoretical constructs underlying the similarities between lifestyle and attachment style. Specifically, they suggested that the individual psychology construct of lifestyle (or style of life) and attachment style should be empirically investigated. The present research…

  16. Attachment, skin deep? Relationships between adult attachment and skin barrier recovery.

    PubMed

    Robles, Theodore F; Brooks, Kathryn P; Kane, Heidi S; Schetter, Christine Dunkel

    2013-06-01

    This study examined the relationship between individual differences in adult attachment and skin barrier recovery. Dating couples (N = 34) completed a self-report measure of attachment anxiety and avoidance, and during two separate laboratory visits, normal skin barrier function was disrupted using a tape-stripping procedure, followed by a 20 min discussion of personal concerns in one visit and relationship problems in the other, counterbalanced randomly across visits. Skin barrier recovery was assessed by measuring transepidermal water loss up to 2 h after skin disruption. Multilevel modeling showed that skin barrier recovery did not differ between the personal concern or relationship problem discussions. Among women, greater attachment anxiety predicted faster skin barrier recovery across the two visits, while greater attachment avoidance predicted slower skin barrier recovery. Among men, greater attachment anxiety predicted slower skin barrier recovery during the personal concern discussion only. The observed effects remained significant after controlling for transepidermal water loss in undisturbed skin, suggesting that the relationship between attachment security and skin barrier recovery was not due to other skin-related factors like sweating. Cortisol changes, self-reported emotions, stress appraisals, and supportiveness ratings were tested as potential mediators, and none explained the relationships between attachment and skin barrier recovery. These findings are the first to demonstrate associations between individual differences in attachment style and restorative biological processes in the skin, even in a sample of young dating couples in satisfied relationships.

  17. Childhood Sexual Abuse, Attachment, and Trauma Symptoms in College Females: The Moderating Role of Attachment

    ERIC Educational Resources Information Center

    Aspelmeier, Jeffery E.; Elliott, Ann N.; Smith, Christopher H.

    2007-01-01

    Objective: The present study tests a model linking attachment, childhood sexual abuse (CSA), and adult psychological functioning. It expands on previous work by assessing the degree to which attachment security moderates the relationship between a history of child sexual abuse and trauma-related symptoms in college females. Method: Self-reports of…

  18. Nuclear reactor fuel rod attachment system

    DOEpatents

    Christiansen, David W.

    1982-01-01

    A reusable system for removably attaching a nuclear reactor fuel rod (12) to a support member (14). A locking cap (22) is secured to the fuel rod (12) and a locking strip (24) is fastened to the support member (14). The locking cap (22) has two opposing fingers (24a and 24b) shaped to form a socket having a body portion (26). The locking strip has an extension (36) shaped to rigidly attach to the socket's body portion (26). The locking cap's fingers are resiliently deflectable. For attachment, the locking cap (22) is longitudinally pushed onto the locking strip (24) causing the extension (36) to temporarily deflect open the fingers (24a and 24b) to engage the socket's body portion (26). For removal, the process is reversed.

  19. [Attachment and Adoption: Diagnostics, Psychopathology, and Therapy].

    PubMed

    Brisch, Karl-Heinz

    2015-01-01

    This presentation describes the development of attachment between adopted children and their adoptive parents with a focus on the particular issues seen in international adoptions. The questions of settling in, trauma in the country of origin, and the motivations of the adoptive parents will be discussed. Diagnosis and various psychopathological manifestations will be examined, as will outpatient and inpatient modes of therapy. The treatment of children of various ages will be covered along with the necessity for intensive counseling and psychotherapy for the adoptive parents. This will enable the parents to work through early trauma, which will give them and their adopted child the basis for developing healthy attachment patterns. This in turn will enable the child to mature and integrate into society. Possibilities of prevention are discussed. Many of the approaches discussed here regarding attachment and adoption may be applied to foster children and their foster parents.

  20. [ADHD and attachment processes: are they related?].

    PubMed

    Franc, N; Maury, M; Purper-Ouakil, D

    2009-06-01

    Attention-deficit/hyperactivity disorder (ADHD) is defined on the basis of developmentally inappropriate inattention, motor activity and impulsivity that emerges early in development and causes impairment in social and academic functioning. ADHD is described as a multifactorial disease, with a well studied genetic vulnerability, and early environmental factors also playing an important role in the development and course of the disorder. Current aetiological models emphasize interaction between genes and environment. The concept of attachment, as proposed by John Bowlby, reflects quality of early interactions, and should therefore be considered as an early developmental factor. First, clinical findings emphasize similitude between both disorders; emotional dysregulation is an important feature in reactive attachment disorder as well as in ADHD. Emotion regulation is highly related to attachment security in young children and could play a part in the development of early attention processes. Moreover, difficult temperament is associated with higher risk for ADHD on the one hand, and can disturb the process of attachment on the other. Parental caregiving - including maternal sensitivity, positive parenting practices - is a main factor involved in the development of attachment, and has shown to be associated with better outcomes in ADHD children, especially with less oppositional/conduct disorders. Second, the aim of our review is to present clinical studies that have looked for a link between ADHD and attachment: the type of attachment could play a part in the course of the disorder: insecure and disorganised attachment types tend to be associated with a higher risk of externalised behaviors in children. For ADHD, this effect seems to be weaker than for other externalised disorders, and has been shown only in populations of at-risk children. Clinical studies also raise the question of possible links between reactive attachment disorder and ADHD. In children suffering

  1. Attaching of strain gages to substrates

    NASA Astrophysics Data System (ADS)

    Lemcoe, M. M.; Pattee, H. E.

    1980-03-01

    A method and apparatus for attaching strain gages to substrates is described. A strain gage having a backing plate is attached to a substrate by using a foil of brazing material between the backing plate and substrate. A pair of electrodes that are connected to a current source, are applied to opposite sides of the backing plate, so that heating of the structure occurs primarily along the relatively highly conductive foil of brazing material. Field installations are facilitated by utilizing a backing plate with wings extending at an upward incline from either side of the backing plate, by attaching the electrodes to the wings to perform the brazing operation, and by breaking off the wings after the brazing is completed.

  2. Attaching of strain gages to substrates

    NASA Technical Reports Server (NTRS)

    Lemcoe, M. M.; Pattee, H. E. (Inventor)

    1980-01-01

    A method and apparatus for attaching strain gages to substrates is described. A strain gage having a backing plate is attached to a substrate by using a foil of brazing material between the backing plate and substrate. A pair of electrodes that are connected to a current source, are applied to opposite sides of the backing plate, so that heating of the structure occurs primarily along the relatively highly conductive foil of brazing material. Field installations are facilitated by utilizing a backing plate with wings extending at an upward incline from either side of the backing plate, by attaching the electrodes to the wings to perform the brazing operation, and by breaking off the wings after the brazing is completed.

  3. Expandable pallet for space station interface attachments

    NASA Technical Reports Server (NTRS)

    Wesselski, Clarence J. (Inventor)

    1988-01-01

    Described is a foldable expandable pallet for Space Station interface attachments with a basic square configuration. Each pallet consists of a series of struts joined together by node point fittings to make a rigid structure. The struts have hinge fittings which are spring loaded to permit collapse of the module for stowage transport to a Space Station in the payload bay of the Space Shuttle, and development on orbit. Dimensions of the pallet are selected to provide convenient, closely spaced attachment points between the node points of the relatively widely spaced trusses of a Space Station platform. A pallet is attached to a strut at four points: one close fitting hole, two oversize holes, and a slot to allow for thermal expansion/contraction and for manufacturing tolerances. Applications of the pallet include its use in rotary or angular joints; servicing of splints; with gridded plates; as instrument mounting bases; and as a roadbed for a Mobile Service Center (MSC).

  4. Role of surface properties in bacterial attachment

    NASA Astrophysics Data System (ADS)

    Conrad, Jacinta; Sharma, Sumedha

    2014-03-01

    Bacterial biofilms foul a wide range of engineered surfaces, from pipelines to membranes to biomedical implants, and lead to deleterious costs for industry and for human health. Designing strategies to reduce bacterial fouling requires fundamental understanding of mechanisms by which bacteria attach to surfaces. We investigate the attachment of Escherichia coli on silanized glass surfaces during flow through a linear channel at flow rates of 0.1-1 mL/min using confocal microscopy. We deposit self-assembled monolayers of organosilanes on glass and track the position and orientation of bacteria deposited on these surfaces during flow using high-throughput image processing algorithms. Here, we report differences in deposition rate and surface-tethered motion of cells as a function of surface charge and surface energy, suggesting that attachment of bacteria on these engineered surfaces is dominated by different physical mechanisms.

  5. Attachment at (not to) work: applying attachment theory to explain individual behavior in organizations.

    PubMed

    Richards, David A; Schat, Aaron C H

    2011-01-01

    In this article, we report the results of 2 studies that were conducted to investigate whether adult attachment theory explains employee behavior at work. In the first study, we examined the structure of a measure of adult attachment and its relations with measures of trait affectivity and the Big Five. In the second study, we examined the relations between dimensions of attachment and emotion regulation behaviors, turnover intentions, and supervisory reports of counterproductive work behavior and organizational citizenship behavior. Results showed that anxiety and avoidance represent 2 higher order dimensions of attachment that predicted these criteria (except for counterproductive work behavior) after controlling for individual difference variables and organizational commitment. The implications of these results for the study of attachment at work are discussed.

  6. Personality disorders and romantic adult attachment: a comparison of secure and insecure attached child molesters.

    PubMed

    Bogaerts, Stefan; Vanheule, Stijn; Desmet, Mattias

    2006-04-01

    This study analyzed personality disorders in a group of 33 securely and 51 insecurely attached child molesters. A total of 51 child molesters were selected from a community based educational training program, and the other group was selected from a Belgian prison (n = 33). Research shows that adult attachment styles and personality disorders share a common underlying structure. It is remarkable that very little is known about differences between securely and insecurely attached child molesters. In this study, the authors found that the schizoid personality disorder differed between securely and insecurely attached child molesters. These findings have implications for the aetiology and treatment of child molesters. Future research is necessary to determine patterns of attachment in relationship to personality disorders.

  7. Family systems theory, attachment theory, and culture.

    PubMed

    Rothbaum, Fred; Rosen, Karen; Ujiie, Tatsuo; Uchida, Nobuko

    2002-01-01

    Family systems theory and attachment theory have important similarities and complementarities. Here we consider two areas in which the theories converge: (a) in family system theorists' description of an overly close, or "enmeshed," mother-child dyad, which attachment theorists conceptualize as the interaction of children's ambivalent attachment and mothers' preoccupied attachment; (b) in family system theorists' description of the "pursuer-distance cycle" of marital conflict, which attachment theorists conceptualize as the interaction of preoccupied and dismissive partners. We briefly review family systems theory evidence, and more extensively review attachment theory evidence, pertaining to these points of convergence. We also review cross-cultural research, which leads us to conclude that the dynamics described in both theories reflect, in part, Western ways of thinking and Western patterns of relatedness. Evidence from Japan suggests that extremely close ties between mother and child are perceived as adaptive, and are more common, and that children experience less adverse effects from such relationships than do children in the West. Moreover, in Japan there is less emphasis on the importance of the exclusive spousal relationship, and less need for the mother and father to find time alone to rekindle romantic, intimate feelings and to resolve conflicts by openly communicating their differences. Thus, the "maladaptive" pattern frequently cited by Western theorists of an extremely close mother-child relationship, an unromantic, conflictual marriage characterized by little verbal communication and a peripheral, distant father, may function very differently in other cultures. While we believe that both theories will be greatly enriched by their integration, we caution against the application of either theory outside the cultures in which they were developed.

  8. Asymmetric epoxidation of unfunctionalized alkenes catalyzed by sugar moiety-modified chiral salen-Mn(III) complexes.

    PubMed

    Zhao, Jiquan; Zhang, Yuecheng; Han, Furong; Zhao, Shanshan

    2009-01-05

    Several chiral Schiff-base ligands with sugar moieties at C-3 (3') or C-5 (5') of salicylaldehyde were synthesized from reaction of salicylaldehyde derivatives with diamine. These ligands coordinated with Mn(III) to afford the corresponding chiral salen-Mn(III) complexes characterized by FT-IR, MS, and elementary analysis. These complexes were used as catalysts for the asymmetric epoxidation of unfunctionalized alkenes. Only weak enantioselectivity is induced by the chiral sugar moieties at C-3 (3') or C-5 (5') in the case of absence of chirality in the diimine bridge moiety. It was also shown that the sugars at C-5 (5') having the same rotation direction of polarized light as the diimine bridge in the catalyst could enhance the chiral induction in the asymmetric epoxidation, but the sugars with the opposite rotation direction would reduce the chiral induction.

  9. Ranking relative hydrogen-bond strengths in hydroxybenzoic acids for crystal-engineering purposes.

    PubMed

    Aakeröy, Christer B; Epa, Kanishka; Forbes, Safiyyah; Schultheiss, Nathan; Desper, John

    2013-10-25

    Systematic co-crystallizations resulting in a total of six new crystal structures involving either 3-hydroxy- or 4-hydroxybenzoic acid, complemented by calculated molecular electrostatic potential surfaces and existing structural data, have shown that in a competitive molecular recognition situation, the -OH moiety is a more effective hydrogen-bond donor than the -COOH moiety which, in turn, highlights that electrostatic charge can offer more useful guidance than acidity for predicting competitive hydrogen-bond preferences.

  10. The Child Attachment Interview: A Narrative Review

    PubMed Central

    Privizzini, Antonella

    2017-01-01

    Attachment theory promoted an impressive body of research on the psychic developmental processes, resulting in studies on both typical and atypical development. Much of the diffusion of the attachment theory in the clinical field was related to the design of reliable instruments to evaluate the organization of attachment in infancy as well as in adulthood. Until recently, the lack of a suitable instrument to assess attachment in middle childhood as well as in adolescence hindered the expansion of research in these developmental phases during which the parent-child relationship takes on a different, albeit still crucial, role. The Child Attachment Interview (CAI), a measure that was recently designed to assess attachment at a representational level in middle childhood and adolescence, filled the measurement gap. The aim of the current review was to summarize previous empirical investigations concerning CAI in order to (a) provide an overview of the state of current research, (b) identify unanswered questions, and (c) propose future research directions. A narrative review was conducted to map the current research findings by searching for the term “Child Attachment Interview” in the Medline, Scopus, Web of Science, and PsychINFO databases, followed by a search in Mendeley. Limits were set to exclude dissertations, chapters in books, and qualitative or theoretical papers, while empirical studies were included if they used the CAI and were published in English language, peer-reviewed journals by July, 2016. The review, which ultimately included 39 studies meeting the criteria, showed that the CAI is a reliable instrument to assess attachment organization in clinical and non-clinical samples, thus providing a worthwhile contribution to the investigation of the influence of the parent-child relationship beyond infancy and early childhood. Nevertheless, the review pointed out a number of relevant open issues, the most critical of which concerned the CAI coding and

  11. Summary of Attached Inflatable Decelerator (AID) Development

    NASA Technical Reports Server (NTRS)

    1968-01-01

    Summary of Attached Inflatable Decelerator (AID) Development. Attached inflatable decelerators (AID) were tested in an environmental chamber, a spin tunnel, and a wind tunnel. Deployment tests were conducted in environmental chamber to examine guided and unguided water alcohol vapor inflation. Subsonic performance tests were conducted in the spin tunnel. The full-scale wind tunnel was used for AID gust and supersonic performance tests. The supersonic tests were conducted at Mach number 3.0 with 12 ounces of fluid and Mach number 2.2 with six ounces of fluid. [Entire movie available on DVD from CASI as Doc ID 20070030992. Contact help@sti.nasa.gov

  12. Adult Attachment Style, Hardiness, and Mood

    DTIC Science & Technology

    2014-04-01

    strange sit- uation” scenario (Ainsworth & Wittig, 1969). By studying how individual children reacted to the same situation, Ains- worth was able to...Solomon (1986) which they called Insecure-Disorganized/Disoriented. Children classified into this attachment category may appear con- fused and dazed in...Separated 72 5.6 Divorced 76 5.9 Widowed 3 0.2 ADULT ATTACHMENT STYLE, HARDINESS, AND MOOD 131 D ow nl oa de d by [ Pa ul T . B ar to ne ] at 1 2: 35

  13. The Child Attachment Interview: A Narrative Review.

    PubMed

    Privizzini, Antonella

    2017-01-01

    Attachment theory promoted an impressive body of research on the psychic developmental processes, resulting in studies on both typical and atypical development. Much of the diffusion of the attachment theory in the clinical field was related to the design of reliable instruments to evaluate the organization of attachment in infancy as well as in adulthood. Until recently, the lack of a suitable instrument to assess attachment in middle childhood as well as in adolescence hindered the expansion of research in these developmental phases during which the parent-child relationship takes on a different, albeit still crucial, role. The Child Attachment Interview (CAI), a measure that was recently designed to assess attachment at a representational level in middle childhood and adolescence, filled the measurement gap. The aim of the current review was to summarize previous empirical investigations concerning CAI in order to (a) provide an overview of the state of current research, (b) identify unanswered questions, and (c) propose future research directions. A narrative review was conducted to map the current research findings by searching for the term "Child Attachment Interview" in the Medline, Scopus, Web of Science, and PsychINFO databases, followed by a search in Mendeley. Limits were set to exclude dissertations, chapters in books, and qualitative or theoretical papers, while empirical studies were included if they used the CAI and were published in English language, peer-reviewed journals by July, 2016. The review, which ultimately included 39 studies meeting the criteria, showed that the CAI is a reliable instrument to assess attachment organization in clinical and non-clinical samples, thus providing a worthwhile contribution to the investigation of the influence of the parent-child relationship beyond infancy and early childhood. Nevertheless, the review pointed out a number of relevant open issues, the most critical of which concerned the CAI coding and

  14. Attachment device for an inflatable protective cushion

    DOEpatents

    Nelsen, J.M.; Luna, D.A.; Gwinn, K.W.

    1998-12-08

    An inflatable cushion assembly for use with an inflator comprises an inflatable cushion having an inner surface, outer surface, and at least one protrusion extending from one of the inner or outer surfaces. The inflatable cushion defines an opening between the inner surface and the outer surface for receiving the inflator. An attachment member contacts the one of the inner or outer surfaces adjacent the opening and includes a groove for receiving the protrusion, the attachment member securing the inflator within the opening. 22 figs.

  15. Attachment device for an inflatable protective cushion

    DOEpatents

    Nelsen, J.M.; Luna, D.A.; Gwinn, K.W.

    1997-11-18

    An inflatable cushion assembly for use with an inflator comprises an inflatable cushion having an inner surface, outer surface, and at least one protrusion extending from one of the inner or outer surfaces. The inflatable cushion defines an opening between the inner surface and the outer surface for receiving the inflator. An attachment member contacts the one of the inner or outer surfaces adjacent the opening and includes a groove for receiving the protrusion, the attachment member securing the inflator within the opening. 22 figs.

  16. How Understanding Attachment Theory Can Help Make Us Better Teachers.

    ERIC Educational Resources Information Center

    Mardell, Benjamin

    1994-01-01

    Attachment theory provides a framework for understanding children's relationships to their primary and secondary caregivers. The theory describes how secure attachment bonds are formed between children and caregivers and the consequences of both secure and insecure attachment relationships. Recommendations for putting attachment theory into…

  17. 14 CFR 33.23 - Engine mounting attachments and structure.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Engine mounting attachments and structure... mounting attachments and structure. (a) The maximum allowable limit and ultimate loads for engine mounting attachments and related engine structure must be specified. (b) The engine mounting attachments and...

  18. Role of Attachment in Response to Pet Loss

    ERIC Educational Resources Information Center

    Field, Nigel P.; Orsini, Lisa; Gavish, Roni; Packman, Wendy

    2009-01-01

    This study examined the impact of attachment on grief severity following the death of a pet. Seventy-one participants who had lost a dog or cat within the past year completed a set of measures that included an attachment measure assessing individual differences in attachment anxiety and avoidance, strength of the past attachment to the pet, the…

  19. Preschool Teacher Attachment, School Readiness and Risk of Learning Difficulties

    ERIC Educational Resources Information Center

    Commodari, Elena

    2013-01-01

    Attachment is the emotional bond between children and their caregivers (parents or otherwise). Infants and young children usually have more than one selective attachment, and all of these attachment relationships, including those between children and teachers, have important effects on cognitive and social development. Secure attachment to a…

  20. Attachment and the Processing of Social Information in Adolescence

    ERIC Educational Resources Information Center

    Dykas, Matthew J.; Cassidy, Jude

    2007-01-01

    A key proposition of attachment theory is that experience-based cognitive representations of attachment, often referred to as internal working models of attachment, influence the manner in which individuals process attachment-relevant social information (Bowlby, 1969/1982, 1973, 1980; Bretherton & Munholland, 1999; Main, Kaplan, & Cassidy, 1985).…

  1. Attachment Disorder: An Emerging Concern for School Counselors.

    ERIC Educational Resources Information Center

    Parker, Kandis Cooke; Forrest, Donald

    1993-01-01

    Explains attachment theory and posits that, if proper bonding and subsequent attachment, usually between mother and child, does not occur, the child develops mistrust and deep-seated rage. Presents evidence of the problem of attachment disorders, lists symptoms of unattached children, examines treatment of attachment disorders, and discusses…

  2. Attachment in Institutionalized and Community Children in Romania

    ERIC Educational Resources Information Center

    Zeanah, Charles H.; Smyke, Anna T.; Koga, Sebastian F.; Carlson, Elizabeth

    2005-01-01

    This study examined attachment in institutionalized and community children 12-31 months of age in Bucharest, Romania. Attachment was assessed using ratings of attachment behaviors and ratings of caregiver descriptions in a structured interview. As predicted, children raised in institutions exhibited serious disturbances of attachment as assessed…

  3. The Freedom to Choose Secure Attachment Relationships in Adulthood

    ERIC Educational Resources Information Center

    Keren, Einat; Mayseless, Ofra

    2013-01-01

    This study was based on the attachment-security hypothesis (H. Latty-Mann & K. E. Davis, 1996) that predicts that all individuals, regardless of attachment style, should demonstrate a preference for secure partners who are most likely to offer attachment security. It was therefore expected that with the transfer of attachment functions from…

  4. An additional fluorenylmethoxycarbonyl (Fmoc) moiety in di-Fmoc-functionalized L-lysine induces pH-controlled ambidextrous gelation with significant advantages.

    PubMed

    Reddy, Samala Murali Mohan; Shanmugam, Ganesh; Duraipandy, Natarajan; Kiran, Manikantan Syamala; Mandal, Asit Baran

    2015-11-07

    In recent years, several fluorenylmethoxycarbonyl (Fmoc)-functionalized amino acids and peptides have been used to construct hydrogels, which find a wide range of applications. Although several hydrogels have been prepared from mono Fmoc-functionalized amino acids, herein, we demonstrate the importance of an additional Fmoc-moiety in the hydrogelation of double Fmoc-functionalized L-lysine [Fmoc(Nα)-L-lysine(NεFmoc)-OH, (Fmoc-K(Fmoc))] as a low molecular weight gelator (LMWG). Unlike other Fmoc-functionalized amino acid gelators, Fmoc-K(Fmoc) exhibits pH-controlled ambidextrous gelation (hydrogelation at different pH values as well as organogelation), which is significant among the gelators. Distinct fibrous morphologies were observed for Fmoc-K(Fmoc) hydrogels formed at different pH values, which are different from organogels in which Fmoc-K(Fmoc) showed bundles of long fibers. In both hydrogels and organogels, the self-assembly of Fmoc-K(Fmoc) was driven by aromatic π-π stacking and hydrogen bonding interactions, as evidenced from spectroscopic analyses. Characterization of Fmoc-K(Fmoc) gels using several biophysical methods indicates that Fmoc-K(Fmoc) has several advantages and significant importance as a LMWG. The advantages of Fmoc-K(Fmoc) include pH-controlled ambidextrous gelation, pH stimulus response, high thermal stability (∼100 °C) even at low minimum hydrogelation concentration (0.1 wt%), thixotropic property, high kinetic and mechanical stability, dye removal properties, cell viability to the selected cell type, and as a drug carrier. While single Fmoc-functionalized L-lysine amino acids failed to exhibit gelation under similar experimental conditions, the pH-controlled ambidextrous gelation of Fmoc-K(Fmoc) demonstrates the benefit of a second Fmoc moiety in inducing gelation in a LMWG. We thus strongly believe that the current findings provide a lead to construct or design various new synthetic Fmoc-based LMW organic gelators for several

  5. Antifouling performance of cross-linked hydrogels: refinement of an attachment model.

    PubMed

    Magin, Chelsea M; Finlay, John A; Clay, Gemma; Callow, Maureen E; Callow, James A; Brennan, Anthony B

    2011-04-11

    Poly(ethylene glycol) dimethacrylate (PEGDMA), PEGDMA-co-glycidyl methacrylate (PEGDMA-co-GMA), and PEGDMA-co-hydroxyethyl methacrylate (PEGDMA-co-HEMA) hydrogels were polymerized using ammonium persulfate and ascorbic acid as radical initiators. Surface energies of the hydrogels and a standard, poly(dimethylsiloxane) elastomer (PDMSe), were characterized using captive bubble and sessile drop measurements, respectively (γ = 52 mN/m, γ(0) = 19 mN/m). The chemical composition of the hydrogels was characterized by attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy. All three hydrogel compositions reduced significantly (p = 0.05) initial attachment of zoospores of the green alga Ulva linza (up to 97%), cells of the diatom Navicula incerta (up to 58%) and the bacterium Cobetia marina (up to 62%), compared to a smooth PDMSe standard. A shear stress (45 Pa), generated in a water channel, eliminated up to 95% of the initially attached cells of Navicula from the smooth hydrogel surfaces relative to smooth PDMSe surfaces. Compared to the PDMSe standard, 79% of the cells of C. marina were removed from all smooth hydrogel compositions when exposed to a 50 Pa wall shear stress. Attachment of spores of the green alga Ulva to microtopographies replicated in PEGDMA-co-HEMA was also evaluated. The Sharklet AF microtopography patterned, PEGDMA-co-HEMA surfaces reduced attachment of spores of Ulva by 97% compared to a smooth PDMSe standard. The attachment densities of spores to engineered microtopographies in PDMSe and PEGDMA-co-HEMA were shown to correlate with a modified attachment model through the inclusion of a surface energy term. Attachment densities of spores of Ulva to engineered topographies replicated in a material other than PDMSe are now correlated with the attachment model (R(2) = 0.80).

  6. In silico identification and crystal structure validation of caspase-3 inhibitors without a P1 aspartic acid moiety

    PubMed Central

    Ganesan, Rajkumar; Jelakovic, Stjepan; Mittl, Peer R. E.; Caflisch, Amedeo; Grütter, Markus G.

    2011-01-01

    Using a fragment-based docking procedure, several small-molecule inhibitors of caspase-3 were identified and tested and the crystal structures of three inhibitor complexes were determined. The crystal structures revealed that one inhibitor (NSC 18508) occupies only the S1 subsite, while two other inhibitors (NSC 89167 and NSC 251810) bind only to the prime part of the substrate-binding site. One of the major conformational changes observed in all three caspase-3–inhibitor complexes is a rotation of the Tyr204 side chain, which blocks the S2 subsite. In addition, the structural variability of the residues shaping the S1–S4 as well as the S1′ subsites supports an induced-fit mechanism for the binding of the inhibitors in the active site. The high-resolution crystal structures reported here provide novel insights into the architecture of the substrate-binding site, which might be useful for the design of more potent caspase inhibitors. PMID:21821879

  7. A Chitosan Derivative Containing Both Carboxylic Acid and Quaternary Ammonium Moieties for the Synthesis of Cyclic Carbonates.

    PubMed

    Besse, Vincent; Illy, Nicolas; David, Ghislain; Caillol, Sylvain; Boutevin, Bernard

    2016-08-23

    Chitosan, a renewable feedstock, is modified and used as a catalytic support in the presence of potassium iodide. The system is highly efficient towards the incorporation of carbon dioxide (CO2 ) into epoxides. It demonstrates very good thermal stability and is recyclable more than five times without loss of activity. The optimal reaction conditions were determined using allylglycidyl ether as a model and extended to a wide range of other epoxides. Cyclic carbonates were obtained with very high yield in a few hours under mild conditions (2-7 bar≈0.2-0.7 MPa, 80 °C) and no solvent.

  8. Calcium phenylphosphonate as a host for 4-aminobenzoic acid-Synthesis, characterization, and cation adsorption from ethanol solution

    SciTech Connect

    Lazarin, Angelica M.; Ganzerli, Thiago A.; Sernaglia, Rosana L.; Andreotti, Elza I.S.; Airoldi, Claudio

    2009-11-15

    Crystalline lamellar calcium phenylphosphonate retained 4-aminobenzoic acid inside its cavity without leaching. The intense infrared bands in the 1160-695 cm{sup -1} interval confirmed the presence of the phosphonate groups attached to the inorganic layer, with sharp and intense peaks in X-ray diffraction patterns, which gave basal distances of 1532 and 1751 pm for the original and the intercalated compounds, respectively. The thermogravimetric curves of both layered compounds showed the release of water molecules and the organic moiety in distinct stages, to yield a final Ca(PO{sub 3}){sub 2} residue. Solid-state {sup 31}P nuclear magnetic resonance spectra presented only one peak for the phenylphosphonate groups attached to the main inorganic polymeric structure near 12.4 ppm. The adsorption isotherms from ethanol gave the maximum adsorption capacities of 1.68 and 0.50 mmol g{sup -1} for copper and cobalt, respectively, whose average stability constants followed Co > Cu; the number of ligands was determined as four for both cations.

  9. Evolution of rosmarinic acid biosynthesis.

    PubMed

    Petersen, Maike; Abdullah, Yana; Benner, Johannes; Eberle, David; Gehlen, Katja; Hücherig, Stephanie; Janiak, Verena; Kim, Kyung Hee; Sander, Marion; Weitzel, Corinna; Wolters, Stefan

    2009-01-01

    Rosmarinic acid and chlorogenic acid are caffeic acid esters widely found in the plant kingdom and presumably accumulated as defense compounds. In a survey, more than 240 plant species have been screened for the presence of rosmarinic and chlorogenic acids. Several rosmarinic acid-containing species have been detected. The rosmarinic acid accumulation in species of the Marantaceae has not been known before. Rosmarinic acid is found in hornworts, in the fern family Blechnaceae and in species of several orders of mono- and dicotyledonous angiosperms. The biosyntheses of caffeoylshikimate, chlorogenic acid and rosmarinic acid use 4-coumaroyl-CoA from the general phenylpropanoid pathway as hydroxycinnamoyl donor. The hydroxycinnamoyl acceptor substrate comes from the shikimate pathway: shikimic acid, quinic acid and hydroxyphenyllactic acid derived from l-tyrosine. Similar steps are involved in the biosyntheses of rosmarinic, chlorogenic and caffeoylshikimic acids: the transfer of the 4-coumaroyl moiety to an acceptor molecule by a hydroxycinnamoyltransferase from the BAHD acyltransferase family and the meta-hydroxylation of the 4-coumaroyl moiety in the ester by a cytochrome P450 monooxygenase from the CYP98A family. The hydroxycinnamoyltransferases as well as the meta-hydroxylases show high sequence similarities and thus seem to be closely related. The hydroxycinnamoyltransferase and CYP98A14 from Coleus blumei (Lamiaceae) are nevertheless specific for substrates involved in RA biosynthesis showing an evolutionary diversification in phenolic ester metabolism. Our current view is that only a few enzymes had to be "invented" for rosmarinic acid biosynthesis probably on the basis of genes needed for the formation of chlorogenic and caffeoylshikimic acid while further biosynthetic steps might have been recruited from phenylpropanoid metabolism, tocopherol/plastoquinone biosynthesis and photorespiration.

  10. Students' Group and Member Attachment to Their University: A Construct Validity Study of the University Attachment Scale

    ERIC Educational Resources Information Center

    France, Megan K.; Finney, Sara J.; Swerdzewski, Peter

    2010-01-01

    This study examined the psychometric properties of scores from the University Attachment Scale, a measure that operationalizes group and member attachment as two separate dimensions of attachment to a university. A two-factor model was championed over a one-factor model providing evidence of a distinction between university attachment and member…

  11. An Exploratory Study of the Association between Reactive Attachment Disorder and Attachment Narratives in Early School-Age Children

    ERIC Educational Resources Information Center

    Minnis, Helen; Green, Jonathan; O'Connor, Thomas G.; Liew, Ashley; Glaser, D.; Taylor, E.; Follan, M.; Young, D.; Barnes, J.; Gillberg, C.; Pelosi, A.; Arthur, J.; Burston, A.; Connolly, B.; Sadiq, F. A.

    2009-01-01

    Objective: To explore attachment narratives in children diagnosed with reactive attachment disorder (RAD). Method: We compared attachment narratives, as measured by the Manchester Child Attachment Story Task, in a group of 33 children with a diagnosis of RAD and 37 comparison children. Results: The relative risk (RR) for children with RAD having…

  12. [Attachment behavior with respect to mothers and fathers and attachment representations in five and seven-year-old children].

    PubMed

    König, Lilith; Gloger-Tippelt, Gabriele; Zweyer, Karen

    2007-01-01

    During preschool and early school age attachment quality can be assessed by different means: at the behavioral level by the Strange Situation (SS), at the representational level by semiprojective methods using story stems or pictures. Both methods gain access to different levels of a theoretically assumed inner working model of attachment, in which attachment at the behavioral level is supposed to be person specific, attachment at the representational level generalized. This study aimed at analyzing whether attachment behavior to mother and father is associated, and how it is linked to the generalized attachment representation. It was also examined whether in the case of no association between mother and father attachment behavior towards the major attachment figure is linked to the attachment representation. In the Duesseldorf study 67 children aged 5 years were observed in the SS with mother, 31 of them also in the SS with father. At the age of 6.5 years an attachment story completion task was conducted. When person specific attachment to mother and father was congruent (SS secure n=6, or insecure n=8) the attachment representation was consistent as well, when father and mother attachment were discrepant no association with attachment representation could be found. The findings did not confirm a stronger influence of the major attachment figure on the formation of the attachment representation.

  13. Bowlby's attachment theory: implications for health visiting.

    PubMed

    Partis, M

    2000-10-01

    This article reviews the current state of research in attachment theory. It also examines the relations between attachment, child care and development, and the significance of attachment to adult functioning and well-being. It seems likely that humans need close emotional relationships or bonds with others. This need applies particularly to infants, who look to parents or other care givers for love and security. The best-known psychological explanation of this need is attachment theory, which has been influential in increasing our understanding of the early mother-infant relationship, and in the formulation of guidelines for child care (Melhuish, 1998). Good-quality parental care may be difficult to define, and questions remain regarding the nature of child care and the consequences that it can have for later development. This article concludes with a discussion of the possible implications for health-visitor intervention within families, which are intended to improve the quality of the relationship between parents or care givers and the infant.

  14. Attachment within the Agency/Communion Paradigm.

    ERIC Educational Resources Information Center

    Sheldon-Keller, Adrienne; West, Malcolm

    This paper synthesizes a variety of perspectives, with an emphasis on attachment theory, on the agency/communion polarity as first defined by David Bakan (1966). The question researchers sought to answer was whether or not agency/communion is best approached as a polarity--opposite and opposing forces, forces in the personality which have often…

  15. Assessing attachment in school-age children.

    PubMed

    Crittenden, Patricia; Kozlowska, Kasia; Landini, Andrea

    2010-04-01

    The School-age Assessment of Attachment (SAA) is a newly developed clinical tool to identify pattern of attachment using the Dynamic-Maturational Model of attachment and adaptation (DMM). Seven picture cards were used to elicit fantasy stories and recalled episodes. The transcribed discourse was analyzed to yield one of 13 DMM attachment classifications, together with possible unresolved traumas and losses, and modifiers (depression and intrusions). In this article, we outline the steps necessary to validate an assessment tool, describe the development of the SAA, and report data from a preliminary clinical study testing the SAA's reliability, validity, and utility. Concurrent construct, familial, and discriminant validity were evaluated in terms of mental health status and exposure to danger on a sample of 5-12-year-old children, drawn from clinical ( n = 51) and normative (n = 40) populations. The SAA (a) differentiated children referred for psychiatric diagnosis from those in the normative population; (b) accounted for 31% of the variance (46% when family variables were added); (c) identified risk children in the normative sample; and (d) suggested risk factors associated with children's psychiatric disorder.

  16. Migrant Farmworkers and Their Attachment to Farmwork.

    ERIC Educational Resources Information Center

    Whitener, Leslie A.

    Using data obtained in December 1979 from the biennial Hired Farm Working Force Survey supplement of the Current Population Survey, case weights were applied to obtain a sample of 149 migrant farmworker case studies (selected from an estimated 217,000 migrant farmworkers) to ascertain the agricultural attachment level of migrant farmworkers in…

  17. Attachment Theory: Implications for School Psychology

    ERIC Educational Resources Information Center

    Kennedy, Janice H.; Kennedy, Charles E.

    2004-01-01

    The effective practice of school psychology requires a strong research and theoretical base, a framework that encompasses developmental processes and outcomes, both adaptive and maladaptive, which facilitates assessment and intervention and offers insight into classroom and family dynamics. Attachment theory provides the school psychologist with…

  18. Childhood Abuse and Attachment Styles of Adolescents

    ERIC Educational Resources Information Center

    Karakus, Ozlem

    2012-01-01

    Introduction: The fact that emotional and social experiences in early childhood period within the family influence the experiences in adolescence and adulthood (communication skills, interpersonal relations) is not a new case. Therefore, the aim of this study is to examine the relationship between childhood abuse and attachment styles. Method: The…

  19. Reactive attachment disorder as an evolutionary adaptation.

    PubMed

    Balbernie, Robin

    2010-05-01

    This paper suggests that the behaviours associated with the formal diagnosis of the "disinhibited" form of reactive attachment disorder (RAD) might be seen as a functional adaptation rather than a mental health problem, a facultative response enhancing the probability of survival that is triggered by certain conditions. Although disinhibited RAD is most commonly observed in institutionalised children, similar behaviours may also be a part of the emotional difficulties displayed by some fostered and adopted children (the latter includes those once institutionalised), and these may demonstrate not so much a discrete attachment disorder as either the need to fend for oneself following loss of dedicated caregiving or a lack of opportunity to build specific intimate relationships with dedicated caregivers. In many cases this may be inextricably mixed with the neurobiological and psychological seqelae of maltreatment. Indiscriminate attachment behaviour, from this proposed evolutionary perspective, is less a syndrome of mental ill-health than an astute survival manoeuvre following being orphaned, abandoned or fecklessly reared. Such a response, allied to the innate facility to access caregiving from different adults, could be expected to be initiated by specific events as are the other attachment configurations. Classing disinhibited RAD as an adaptation has implications for helping children brought up under extreme duress when their caregiving environment has changed for the better.

  20. Attachment Styles, Abuse Experiences and Depression

    ERIC Educational Resources Information Center

    Gunduz, Bulent; Capri, Burhan; Akbay, Sinem Evin; Tunc, Aygul

    2013-01-01

    This study aims to examine the relationship between abuse experiences, depression and attachment styles. The data for this study was collected from 251 students (123 females and 128 males) who attend Mersin University. As a part of the data collection, students completed the Experiences in Affiliation Inventory, Childhood Trauma Scale and Brief…