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Sample records for diquinone moieties technical

  1. Photoinitiated electron transfer in multichromophoric species: Synthetic tetrads and pentads featuring diquinone moieties. Technical progress report, September 1, 1991--30 April 1992

    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.

  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. Bis(calix[4]diquinone) receptors: cesium- and rubidium-selective redox-active ionophores.

    PubMed

    Webber, Philip R A; Beer, Paul D; Chen, George Z; Felix, Vitor; Drew, Michael G B

    2003-05-14

    A new class of redox-active ionophore comprised of two calix[4]diquinone moieties connected through either alkylene or pyridylene linkages has been developed. Spectroscopic and electrochemical investigations, X-ray crystal structure analyses, and molecular modeling studies show butylene- and propylene-linked members of this family of redox-active receptors exhibit remarkable selectivity preferences and substantial electrochemical recognition effects toward cesium and rubidium cations.

  4. Temperature-induced solid-state valence tautomeric interconversion in two cobalt-Schiff base diquinone complexes.

    PubMed

    Cador, Olivier; Chabre, Françoise; Dei, Andrea; Sangregorio, Claudio; van Slageren, Joris; Vaz, Maria G F

    2003-10-06

    The mixed-ligand complexes [Co(III)(tpy)(Cat-N-SQ)]Y and [Ni(II)(tpy)(Cat-N-BQ)]PF(6) (tpy = 2,2':6',2' '-terpyridine; Cat-N-BQ, Cat-N-SQ = mononegative and radical dinegative Schiff base diquinone ligand; Y = PF(6), BPh(4)) were prepared. Structural and spectroscopic data support the different charge distribution of the two compounds. The temperature-dependent electronic and spectral properties of solutions containing the [Co(III)(tpy)(Cat-N-SQ)](+) suggest that this compound undergoes a thermally driven valence tautomeric interconversion to [Co(II)(tpy)(Cat-N-BQ)](+) complex, the metal ion being in high-spin configuration. The comparison of the electrochemical properties of the cobalt and nickel derivatives supports the observed behavior. The same interconversion process was found to occur also in the solid state with a significant higher T(c) value than in solution. It was found that the previously reported [Co(III)(Cat-N-BQ)(Cat-N-SQ)] shows a similar behavior. The large difference between the interconversion T(c) in the solid state and in solution is suggested to come from the entropy changes associated with the modifications of vibronic interactions.

  5. Metabolite identification studies on amiodarone in in vitro (rat liver microsomes, rat and human liver S9 fractions) and in vivo (rat feces, urine, plasma) matrices by using liquid chromatography with high-resolution mass spectrometry and multiple-stage mass spectrometry: characterization of the diquinone metabolite supposedly responsible for the drug's hepatotoxicity.

    PubMed

    Ramesh Varkhede, Ninad; Jhajra, Shalu; Suresh Ahire, Deepak; Singh, Saranjit

    2014-02-28

    Several mechanisms have been anticipated for the toxicity of amiodarone, such as oxidative stress, lipid peroxidation, phospholipidosis, free radical generation, etc. Amiodarone is structurally similar to benzbromarone, an uricosuric agent, which was withdrawn from European markets due to its idiosyncratic hepatotoxicity. A proposed reason behind the toxicity of benzbromarone was the production of a reactive ortho-diquinone metabolite, which was found to form adducts with glutathione. Therefore, taking a clue that a similar diquinone metabolite of amiodarone may be the reason for its hepatotoxicity, metabolite identification studies were carried out on the drug using liquid chromatography/mass spectrometry (LC/MS) tools. The studies involved in vitro (rat liver microsomes, rat liver S9 fraction, human liver S9 fraction) and in vivo (rat feces, urine, plasma) models, wherein the samples were analyzed by employing LC/HRMS, LC/MS(n) and HDE-MS. A total of 26 metabolites of amiodarone were detected in the investigated in vitro and in vivo matrices. The suspected ortho-diquinone metabolite was one of them. The formation of the same might be an added reason for the hepatotoxicity shown by the drug. Copyright © 2013 John Wiley & Sons, Ltd.

  6. 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.

  7. 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.

  8. 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.

  9. BIOSYNTHESIS OF THE PHENYLPROPANOID MOIETY OF CHLORAMPHENICOL,

    DTIC Science & Technology

    measured. D-Glucose, labelled in carbons 1 or 2 or uniformly, was an efficient precursor of the p-nitrophenylserinol moiety and of the phenylpropanoid ...amino acids of the mycelium. Since phenylalanine and tyrosine were incorporated into the mycelium the biosynthetic route to the phenylpropanoid portion

  10. 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)

  11. 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)

  12. 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

    2017-05-01

    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. Copyright © 2017 Elsevier Inc. All rights reserved.

  13. 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.

  14. A review on various heterocyclic moieties and their antitubercular activity.

    PubMed

    Sharma, S; Sharma, P K; Kumar, N; Dudhe, R

    2011-07-01

    Tuberculosis (TB), a contagious infection caused by Mycobacterium tuberculosis, still remains the leading cause of the worldwide death among the infectious disease. Different moieties like pyrazoline, benzimidazol, purines, thiazole, flouroquinolones, quinoxaline, oxadiazol, pyrazol, thiozolidinones and azetidinones have been studied, synthesized and evaluated worldwide against M. tuberculosis to show their antitubercular activity. Copyright © 2011 Elsevier Masson SAS. All rights reserved.

  15. 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.

  16. Compounds containing meta-biphenylenedioxy moieties and polymers therefrom

    NASA Technical Reports Server (NTRS)

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

    1993-01-01

    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 prepare polyimide polymers. These polymers are used to make films, coatings, and selective membranes.

  17. 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.

  18. Examination of adipose depot-specific PPAR moieties.

    PubMed

    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. 2010 Elsevier Inc. All rights reserved.

  19. Molecular rectifiers: a new design based on asymmetric anchoring moieties.

    PubMed

    Van Dyck, Colin; Ratner, Mark A

    2015-03-11

    The quest for a molecular rectifier is among the major challenges of molecular electronics. We introduce three simple rules to design an efficient rectifying molecule and demonstrate its functioning at the theoretical level, relying on the NEGF-DFT technique. The design rules notably require both the introduction of asymmetric anchoring moieties and a decoupling bridge. They lead to a new rectification mechanism based on the compression and control of the HOMO/LUMO gap by the electrode Fermi levels, arising from a pinning effect. Significant rectification ratios up to 2 orders of magnitude are theoretically predicted as the mechanism opposes resonant to nonresonant tunneling.

  20. Technical writing versus technical writing

    NASA Technical Reports Server (NTRS)

    Dillingham, J. W.

    1981-01-01

    Two terms, two job categories, 'technical writer' and 'technical author' are discussed in terms of industrial and business requirements and standards. A distinction between 'technical writing' and technical 'writing' is made. The term 'technical editor' is also considered. Problems inherent in the design of programs to prepare and train students for these jobs are discussed. A closer alliance between industry and academia is suggested as a means of preparing students with competent technical communication skills (especially writing and editing skills) and good technical skills.

  1. 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.

  2. 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. Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. 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.

  4. Compounds Combining Aminoadamantane and Monoterpene Moieties: Cytotoxicity and Mutagenic Effects.

    PubMed

    Suslov, Evgeniy V; Ponomarev, Konstantin Yu; Rogachev, Artem D; Pokrovsky, Michail A; Pokrovsky, Andrey G; Pykhtina, Maria B; Beklemishev, Anatoly B; Korchagina, Dina V; Volcho, Konstantin P; Salakhutdinov, Nariman F

    2015-01-01

    A series of secondary amines combining monoterpenoid and aminoadamantane moieties have been synthesized. Their cytotoxic activity against human cancer cells CEM-13, MT-4, and U-937 has been studied for the first time. Most of the obtained compounds exhibited a significant cytotoxic activity with the median cytotoxic dose (CTD50) ranging from 6 to 84 µM. The most promising results were obtained for compound 2b which was synthesized from 1-aminoadamantane and (-)-myrtenal and revealed a high activity against all tumor lines used (CTD50 = 12 ÷ 21 µM) along with low toxicity with respect to MDCK cells (CTD50 = 1500 µM). The synthesized amines do not exert the genotoxic effect on cells of the biosensor strain based on recombinant E. coli cells bearing the pRAC-gfp plasmid.

  5. 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

  6. 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).

  7. "Technical" Writing vs. Technical "Writing."

    ERIC Educational Resources Information Center

    Dillingham, J. W.

    Technical writers must have a working knowledge of technology in order to rearrange material others provide, but they do not have the expertise needed to originate materials; that is the job of the technical author. Another job function is that of technical editor--a person who can write, can perform the policy making tasks of an editor, and who…

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

    PubMed

    Haraldsdóttir, Hulda S; Fleming, Ronan M T

    2016-11-01

    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.

  9. 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

  10. 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.

  11. 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.

  12. Photochemistry and photophysics of ketyl radicals containing the anthrone moiety

    SciTech Connect

    Netto-Ferreira, J.C.; Murphy, W.F.; Redmond, R.W.; Scaiano, J.C. )

    1990-05-23

    The photochemistry of several ketones containing an anthrone moiety has been employed to produce the corresponding ketyl radicals 1-4 by photoreduction in the presence of suitable hydrogen donors. The excited-state behavior of these radicals has been examined with use of two-laser, two-color techniques. The lifetimes for the excited ketyl radicals, ranging from 7.9 ns for 3 to 33 ns for 2, are longer than that observed for benzophenone ketyl, thus suggesting that conformational restrictions play a key role in controlling excited radical lifetimes. In the case of 3 the dominant mode of decay involves loss of a benzyl radical from the 10-position, while for 1 and 2 the process involves the loss of a hydrogen atom from the hydroxylic position; in the case of 2 this has been confirmed by Raman spectroscopy. The quantum yields of radical photobleaching are 0.20, 0.46, and 0.75 for 1, 2, and 3, respectively, while 4 is essentially photostable.

  13. 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.

  14. Mass spectrometric study of the amipurimycin hexopyranosidic sugar moiety

    NASA Astrophysics Data System (ADS)

    Almoster Ferreira, M. A.; Borges, C.; Oliveira, M. C.; Pocsfalvi, G.; Rauter, A. P.; Fernandes, A. C.

    1997-11-01

    Amipurimycin is a natural nucleoside that displays a remarkable activity in vitro and in vivo against Pyricularia oryzae, which is responsible for the rice blast disease. Six important precursors for the synthesis of the Amipurimycin sugar moiety were prepared. In order to obtain structural information a mass spectrometric study of these compounds was performed using liquid secondary ion mass spectrometry (LSIMS) with high-energy collision-induced dissociation (CID) experiments on a four-sector instrument. Elimination of methanol is the preferential fragmentation path for five of the six protonated molecules, indicating that protonation plays an important role in the process, whilst for the other protonated molecule loss of water is the main fragmentation. Examination of the [M + Li]+ precursor ion spectra shows that loss of methanol does not occur in three of them, but in the other three gives rise to fairly abundant ions, indicating that in this case methanol elimination implies intramolecular hydrogen transfer, the resulting ion having a very stable structure.

  15. 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.

  16. TECHNICAL EDUCATION.

    ERIC Educational Resources Information Center

    FRIGIOLA, NICHOLAS F.

    THE CONSENSUS OF OUR NATION'S LEADERS AFFIRMS THAT THE COUNTRY'S GREATEST TECHNICAL EDUCATION VOID IS IN THE AREA BETWEEN THE 12TH GRADE AND THE BACCALAUREATE DEGREE. THE IMPACT OF ACCELERATED PROGRESS IN TECHNOLOGICAL ACHIEVEMENTS MAKES TECHNICAL EDUCATION MANDATORY IF THE MANPOWER SHORTAGE IS NOT TO BECOME A NATIONAL EMERGENCY. BECAUSE NEARLY 80…

  17. 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.

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

    DOE PAGES

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

    2016-11-21

    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 moietymore » 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. Finally, we also give examples of new applications made possible by elucidating the atomic structure of conserved moieties.« less

  19. Studies on the supramolecular shape memory polyurethane containing pyridine moieties

    NASA Astrophysics Data System (ADS)

    Shaojun, Chen

    Fabricating smart materials with supramolecular switch is an attractive research topic. In this study, supramolecular polyurethane networks containing pyridine moieties (PUPys) were synthesized from N,N-bis(2-hydroxylethyl)isonicotinamide (BINA), hexamethylene diisocyanate (HDI), 4, 4-diphenylmethane diisocyanate (MDI) and 1,4-butanediol (BDO). A series of studies were carried out to investigate the supramolecular structure, morphology and shape memory properties including of thermal-induced shape memory effect and moisture-sensitive shape memory effect. Results show that hydrogen-bonded supramolecular structure and phase separation morphology are formed in the PUPys. The glass transition temperature (Tg) of soft phase is controlled by the hydrogen bonding while the hard phase grows up from amorphous phase to crystalline phase as the BINA content increases. The addition of MDI-BDO promotes the formation of amorphous hard phase. PUPys have high shape fixity and high shape recovery with the recovery temperature of 45 °C-55 °C. To achieve satisfying shape recovery, 30wt% BINA contents are required. The addition of MDI-BDO improves the shape recovery force. In addition, PUPys have high moisture absorption which increases with the increase of temperature, relative humidity, BINA content as well as the decrease of MDI-BDO content. The final shape recovery decreases with the decrease of BINA content significantly and the strain recovery start time, strain recovery time, strain recovery end time and the time length are also short in the higher BINA content PUPys. Moreover, it is found that the low critical value of BINA unit for PUPys having moisture-sensitive SME is still 30wt%. The addition of MDI-BDO improves the moisture-sensitive shape recovery. Finally, it is proposed that the hydrogen bonding present in the pyridine ring serves as "switch" whereas the formed hard phase via hydrogen bonding present in the urethane groups acts as the physical netpoints for the both

  20. 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.

  1. 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.

  2. Chlordane (Technical)

    Integrated Risk Information System (IRIS)

    Chlordane ( Technical ) ; CASRN 12789 - 03 - 6 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarc

  3. Technical Mathematics.

    ERIC Educational Resources Information Center

    Flannery, Carol A.

    This manuscript provides information and problems for teaching mathematics to vocational education students. Problems reflect applications of mathematical concepts to specific technical areas. The materials are organized into six chapters. Chapter 1 covers basic arithmetic, including fractions, decimals, ratio and proportions, percentages, and…

  4. Technical Mathematics.

    ERIC Educational Resources Information Center

    Flannery, Carol A.

    This manuscript provides information and problems for teaching mathematics to vocational education students. Problems reflect applications of mathematical concepts to specific technical areas. The materials are organized into six chapters. Chapter 1 covers basic arithmetic, including fractions, decimals, ratio and proportions, percentages, and…

  5. 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

  6. {sup 31}P NMR analysis of coal moieties bearing -OH, -NH, and -SH functions. Final technical report

    SciTech Connect

    Verkade, J.G.

    1991-08-31

    NMR reagents for the speciation and quantitation of labile-hydrogen functional groups and sulfur groups in coal ligands have been synthesized and evaluated. These reagents, which contain the NMR-active nuclei {sup 31}p, {sup 119}Sn or {sup 195}pt, were designed to possess improved chemical shift resolution over reagents reported in the literature. Our efforts were successful in the case of the new {sup 31}p and {sup 119}Sn reagents we developed, but the {sup 195}pt work on sulfur groups was only partially successful in as much as the grant came to a close and was not renewed. Our success with {sup 31}P and {sup 119}Sn NMR reagents came to the attention of Amoco and they have recently expressed interest in further supporting that work. A further measure of the success of our efforts can be seen in the nine publications supported by this grant which are cited in the reference list.

  7. Ferricyanide-based analysis of aqueous lignin suspension revealed sequestration of water-soluble lignin moieties

    SciTech Connect

    Joshua, C. J.; Simmons, B. A.; Singer, S. W.

    2016-06-02

    This study describes the application of a ferricyanide-based assay as a simple and inexpensive assay for rapid analysis of aqueous lignin samples. The assay measures the formation of Prussian blue from the redox reaction between a mixture of potassium ferricyanide and ferric chloride, and phenolic hydroxyl groups of lignin or lignin-derived phenolic moieties. This study revealed that soluble lignin moieties exhibited stronger ferricyanide reactivity than insoluble aggregates. The soluble lignin moieties exhibited higher ferricyanide reactivity because of increased access of the phenolic hydroxyl groups to the ferricyanide reagents. Ferricyanide reactivity of soluble lignin moieties correlated inversely with the molecular weight distributions of the molecules, probably due to the involvement of phenolic hydroxyl groups in bond formation. The insoluble lignin aggregates exhibited low ferricyanide reactivity due to sequestration of the phenolic hydroxyl groups within the solid matrix. The study also highlighted the sequestration of polydispersed water-soluble lignin moieties by insoluble aggregates. The sequestered moieties were released by treatment with 0.01 M NaOH at 37 °C for 180 min. The redox assay was effective on different types of lignin extracts such as Klason lignin from switchgrass, ionic-liquid derived lignin from Eucalyptus and alkali lignin extracts. The assay generated a distinct profile for each lignin sample that was highly reproducible. The assay was also used to monitor consumption of syringic acid by Sphingobium sp. SYK-6. The simplicity and reproducibility of this assay makes it an excellent and versatile tool for qualitative and semi-quantitative characterization and comparative profiling of aqueous lignin samples.

  8. Ferricyanide-based analysis of aqueous lignin suspension revealed sequestration of water-soluble lignin moieties

    DOE PAGES

    Joshua, C. J.; Simmons, B. A.; Singer, S. W.

    2016-06-02

    This study describes the application of a ferricyanide-based assay as a simple and inexpensive assay for rapid analysis of aqueous lignin samples. The assay measures the formation of Prussian blue from the redox reaction between a mixture of potassium ferricyanide and ferric chloride, and phenolic hydroxyl groups of lignin or lignin-derived phenolic moieties. This study revealed that soluble lignin moieties exhibited stronger ferricyanide reactivity than insoluble aggregates. The soluble lignin moieties exhibited higher ferricyanide reactivity because of increased access of the phenolic hydroxyl groups to the ferricyanide reagents. Ferricyanide reactivity of soluble lignin moieties correlated inversely with the molecular weightmore » distributions of the molecules, probably due to the involvement of phenolic hydroxyl groups in bond formation. The insoluble lignin aggregates exhibited low ferricyanide reactivity due to sequestration of the phenolic hydroxyl groups within the solid matrix. The study also highlighted the sequestration of polydispersed water-soluble lignin moieties by insoluble aggregates. The sequestered moieties were released by treatment with 0.01 M NaOH at 37 °C for 180 min. The redox assay was effective on different types of lignin extracts such as Klason lignin from switchgrass, ionic-liquid derived lignin from Eucalyptus and alkali lignin extracts. The assay generated a distinct profile for each lignin sample that was highly reproducible. The assay was also used to monitor consumption of syringic acid by Sphingobium sp. SYK-6. The simplicity and reproducibility of this assay makes it an excellent and versatile tool for qualitative and semi-quantitative characterization and comparative profiling of aqueous lignin samples.« less

  9. 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.

  10. Synthesis and Biological Evaluation of a Valinomycin Analog Bearing a Pentafluorophenyl Active Ester Moiety.

    PubMed

    D'Accolti, Lucia; Denora, Nunzio; La Piana, Gianluigi; Marzulli, Domenico; Siwy, Zuzanna S; Fusco, Caterina; Annese, Cosimo

    2015-12-18

    A valuable analog of the K(+)-ionophore valinomycin (1), bearing a pentafluorophenyl ester moiety, has been obtained by selective reaction between the tertiary hydroxyl moiety of analog 2 (available from valinomycin hydroxylation) and the isocyanate group of pentafluorophenyl N-carbonyl glycinate (3) catalyzed by bis(N,N-dimethylformamide)dichlorodioxomolybdenum(VI). LC-HRMS studies show that analog 4 undergoes easy derivatization under mild conditions by reaction with OH- and NH2-containing compounds. Mitochondrial depolarization assays suggest that 4 acts as a K(+)-ionophore, provided that the glycine carboxyl group is appropriately masked.

  11. Synthesis and carbonic anhydrase inhibitory effects of new N-glycosylsulfonamides incorporating the phenol moiety.

    PubMed

    Riafrecha, Leonardo E; Bua, Silvia; Supuran, Claudiu T; Colinas, Pedro A

    2016-08-15

    A small series of N-glycosylsulfonamides incorporating the phenol moiety has been prepared by Ferrier sulfonamidoglycosylation of d-glycals. N-Glycosides were tested for the inhibition of four isoforms of carbonic anhydrase. In this study, all compounds showed good inhibitory activity against hCA I and II, with selectivity against the cytosolic hCA II versus the tumor associated isozymes. These results confirm that attaching carbohydrate moieties to CA phenol pharmacophore improves and enhances its inhibitory activity. Copyright © 2016 Elsevier Ltd. All rights reserved.

  12. 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.

  13. 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.

  14. 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.

  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.

    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.

  17. 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.

  18. 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.

  19. 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.)

  20. 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.)

  1. 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

  2. Solution structure of (d(GGTATACC))/sub 2/: wrinkled D structure of the TATA moiety

    SciTech Connect

    Zhou, N.; Bianucci, A.M.; Pattabiraman, N.; James, T.L.

    1987-12-01

    Phase-sensitive two-dimensional nuclear Overhauser effect spectra of (dGGTATACC))/sub 2/ in aqueous deuterium oxide solution at four mixing times were quantified to give all nonoverlapping cross-peak intensities. A structural model for (d(GGTATACC))/sub 2/ was built in which the GG- and -CC moieties were in the B-DNA form, while the middle -TATA- moiety was in the wrinkled-D form (BDB model). This model was subjected to energy refinement by molecular mechanics calculations with the program AMBER. Counterions (Na/sup +/) were added to neutralize the charges, and water molecules were placed bridging across the minor groove. A complete relaxation matrix analysis was used to calculate two-dimensional nuclear Overhauser effect spectra of (d(GGTATACC))/sub 2/ from the above models (before and after energy refinement) and from four other (d(GGTATACC))/sub 2/ structural models: regular A, crystalline A, regular B, and energy-minimized B. Among them, the energy-minimized BDB model yielded a set of theoretical spectra that gave the best fit to the experimental spectra. It was also the energetically most stable. Therefore, it is a good representation of the ensemble- and time-averaged structure of the octamer in solution. This model has backbone torsion angles similar to those of B-form DNA in the GG- and -CC moieties and torsion angles similar to those of wrinkled D for DNA in the -TATA- moiety. The base stacking and base pairing are not interrupted at the junctions between the two structural moieties. Its minor groove is narrower than that of B DNA, and the solvent-accessible surface of the minor groove forms a closed hydration tunnel in the middle -TATA- segment.

  3. Influence of gallate and pyrogallol moieties on the intestinal absorption of (-)-epicatechin and (-)-epicatechin gallate.

    PubMed

    Tagashira, Tomohiko; Choshi, Tominari; Hibino, Satoshi; Kamishikiryou, Jun; Sugihara, Narumi

    2012-10-01

    The cellular accumulation of individual catechins was measured as an index of intestinal absorption to clarify the interactions among catechins. The cellular accumulation of (-)-epicatechin (EC) increased in the presence of other catechins. The ability of gallate catechin such as (-)-epigallocatechin gallate (EGCG) and (-)-epicatechin gallate (ECG) to increase the cellular accumulation of EC was greater than that of nongallate catechins. Gallic acid octyl ester (GAO) also increased the cellular accumulation of EC by 426% as compared with that in untreated cells. Conversely, the cellular accumulation of ECG was not influenced by other catechins, but it increased by 54% in the presence of GAO. Experiments using GAO derivatives indicated that the gallate moiety required the presence of a catechol group and a neighboring carbonyl group, whereas the pyrogallol moiety, without a neighboring carbonyl group, required 3 hydroxyl groups to increase the cellular accumulation of EC. Furthermore, gallate esters required long carbon chains to increase the same. The experiment using EGCG, GAO, or their derivatives indicated that the ability of gallate or pyrogallol moiety to increase the cellular accumulation of EC was restricted by their hydrophobicity. These results suggest that the co-administration of foods containing functional materials such as gallate or pyrogallol moieties, increases the intestinal absorption of catechin. The cellular accumulation of (-)-epicatechin increased by the gallate or pyrogallol moiety in catechin structure. The interaction among catechins appeared to affect intestinal absorption of catechin. The bioavailability of catechin may be improved by co-administration of functional foods. © 2012 Institute of Food Technologists®

  4. 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.

  5. Design, synthesis, and antiviral activity of novel rutin derivatives containing 1, 4-pentadien-3-one moiety.

    PubMed

    Han, Yu; Ding, Yan; Xie, Dandan; Hu, Deyu; Li, Pei; Li, Xiangyang; Xue, Wei; Jin, Linhong; Song, Baoan

    2015-03-06

    Rutin (compound 5) and some compounds (compounds 1-4 and 6) were isolated from Artemisia princeps Pamp (A. princeps Pamp.) and a series of novel rutin derivatives containing 1,4-pentadien-3-one moiety were designed and synthesized. The target compounds were characterized by proton nuclear magnetic resonance spectroscopy ((1)H NMR), carbon nuclear magnetic resonance spectroscopy ((13)C NMR), and ESI-MS. Bioassay results indicated that some of the compounds showed good to excellent antiviral activities against tobacco mosaic virus (TMV) and cucumber mosaic virus (CMV) at 500 μg/mL in vivo. The 50% effective concentrations (EC50) of the compound 7r against CMV was 394.78 μg/mL, which was better than that of Ningnanmycin (432.22 μg/mL). These results indicated that novel rutin derivatives containing 1,4-pentadien-3-one moiety can effectively control CMV.

  6. 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.

  7. 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

  8. Decisive interactions between the heterocyclic moiety and the cluster observed in polyoxometalate-surfactant hybrid crystals.

    PubMed

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

    2015-04-16

    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.

  9. 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.

  10. 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

  11. Antiproliferative activity and SARs of caffeic acid esters with mono-substituted phenylethanols moiety.

    PubMed

    Xie, Jin; Yang, Fengzhi; Zhang, Man; Lam, Celine; Qiao, Yixue; Xiao, Jia; Zhang, Dongdong; Ge, Yuxuan; Fu, Lei; Xie, Dongsheng

    2017-01-15

    A series of CAPE derivatives with mono-substituted phenylethanols moiety were synthesized and evaluated by MTT assay on growth of 4 human cancer cell lines (Hela, DU-145, MCF-7 and ECA-109). The substituent effects on the antiproliferative activity were systematically investigated for the first time. It was found that electron-donating and hydrophobic substituents at 2'-position of phenylethanol moiety could significantly enhance CAPE's antiproliferative activity. 2'-Propoxyl derivative, as a novel caffeic acid ester, exhibited exquisite potency (IC50=0.4±0.02 & 0.6±0.03μM against Hela and DU-145 respectively). Copyright © 2016 Elsevier Ltd. All rights reserved.

  12. Synthesis and properties of new TTP donors composed of TTF and TSF moieties

    NASA Astrophysics Data System (ADS)

    Ishizu, K.; Watanabe, M.; Tanahashi, T.; Misaki, Y.; Ashizawa, M.; Mori, T.

    2008-10-01

    Several derivatives of bis-fused donors composed of TTF and TSF (1, 2), and the vinyl analogues (3,4), have been synthesized. Cylic voltamograms of 1-4 consist of four pairs of one-electron redox waves. The first redox potential of la is comparable to that of the corresponding sulfur analogues BDT-TTP, indicating the positive charge formed by the first oxidation mainly distributes over the TTF moiety. In contrast, the second redox potential is higher than that of BDT-TTP due to occurrence of the second oxidation on the TSF moiety. The donors la, 3a and 4a form highly conducting TCNQ complexes and I3- salts (σrt = 3 - 36 S cm-1 on a compressed pellet) with very low activation energies of 0.0094 - 0.040 eV.

  13. 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.

  14. 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.

  15. 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.

  16. A highly sensitive method for analyses of sugar moieties of glycoproteins by fluorescence labeling.

    PubMed

    Hase, S; Ikenaka, T; Matsushima, Y

    1981-08-01

    The sensitivity of a fluorescence labeling method ((1979). J. Biochem. 85, 989--994; 995--1002) for structure analyses of asparagine-linked sugar moieties of glycoproteins was increased by using HPLC with a fluorescence detector. Sugar moieties were separated from polypeptide portions by hydrazinolysis. Free amino groups thus exposed were acetylated and the reducing ends of sugar chains were reductively aminated with a fluorescent reagent, 2-aminopyridine, by the use of sodium cyanoborohydride. The pyridylamino derivatives were purified on a Dowex 1 column to eliminate undesired substances. The separation and identification of the pyridylamino derivatives were carried out by HPLC with a column of C18 reversed phase or gel permeation phase. As little as 0.1 pmol of pyridylamino derivatives can be detected. Ten microgram of Taka-amylase A was easily detected by this system. The method was also applied to some other glycoproteins.

  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. 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)

  19. 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. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  20. 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.

  1. 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.

  2. Effects of organic moieties on the photoluminescence spectra of perovskite-type tin bromide based compounds

    NASA Astrophysics Data System (ADS)

    Papavassiliou, George C.; Vidali, Maria-Sofia; Pagona, Georgia; Mousdis, George A.; Karousis, Nikolaos; Koutselas, Ioannis

    2015-04-01

    The photoluminescence (PL) and optical absorption (OA) spectra of some compounds of the type (SC)SnBr3, (BC)2SnBr4, and (SC)(BC)2Sn2Br7 (where SC is CH3NH3 + or Cs+; BC is C4H9NH3 + ,CH3C6H4CH2NH3 + ,C12H25NH3 + ,C18H37NH3 + and 1-naphthylmethyl ammonium group), in the forms of thin deposits on several substrates, are investigated. Generally, using the 350 nm as excitation line, the obtained PL spectra of compounds of the type (BC)2SnBr4 with short alkyl chain-length in the alkyl ammonium moiety, show broad and strong bands. For example, the PL spectra of compound (C4H9NH3)2SnBr4 exhibit a weak band at ca 475 nm, attributed to free-excitons and a broad and strong band at ca 570 nm, attributed to radiative decay of self-trapped excitons in the inorganic moiety. This is a bright yellow-orange emission, which can be seen by naked eye, even at room temperature. In the case of the compounds with long alkyl chain-length in the alkyl ammonium moiety, the PL spectra are dominated by an excitonic band, which occurs close to the corresponding fundamental OA edge. The PL spectrum of (1-naphthylmethyl ammonium)2SnBr4 shows the strong red band with main maxima at ca 603 and 642 nm, arising from tetramers of naphthyl moieties. Also, the PL spectra of the compounds of the type (SC)SnBr3 and (SC)(BC)2Sn2Br7, after grinding, show strong bands at 600-620 nm.

  3. 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.

  4. Synthesis and antihyperglycemic evaluation of new 2,4-thiazolidinediones having biodynamic aryl sulfonylurea moieties.

    PubMed

    Jawale, Dhanaji V; Pratap, Umesh R; Rahuja, Neha; Srivastava, Arvind K; Mane, Ramrao A

    2012-01-01

    New 2,4-thiazolidinediones with aryl sulfonylurea moieties have been synthesized by condensing various substituted sulfonamides and 5-(isocyanatomethyl) thiazolidino-2,4-dione. The isocyanomethyl thiazolidinedione was obtained by using the Curtius rearrangement, starting from known 2,4-dioxo-5-thiazolidineacetic acid. The newly synthesized compounds have been evaluated for the antihyperglycemic activity in normal rats model and among these compounds showed significant antihyperglycemic activity in sucrose loaded rat model. Copyright © 2011 Elsevier Ltd. All rights reserved.

  5. Chemical synthesis and biological activities of novel pleuromutilin derivatives with substituted amino moiety.

    PubMed

    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.

  6. A Phage Display Screening Derived Peptide with Affinity for the Adeninyl Moiety

    PubMed Central

    Elmlund, Louise; Söderberg, Pernilla; Suriyanarayanan, Subramanian; Nicholls, Ian A.

    2014-01-01

    Phage display screening of a surface-immobilized adenine derivative led to the identification of a heptameric peptide with selectivity for adenine as demonstrated through quartz crystal microbalance (QCM) studies. The peptide demonstrated a concentration dependent affinity for an adeninyl moiety decorated surface (KD of 968 ± 53.3 μM), which highlights the power of piezoelectric sensing in the study of weak interactions. PMID:25587414

  7. 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.

  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. Potential Role for a Carbohydrate Moiety in Anti-Candida Activity of Human Oral Epithelial Cells

    PubMed Central

    Steele, Chad; Leigh, Janet; Swoboda, Rolf; Ozenci, Hatice; Fidel, Paul L.

    2001-01-01

    Candida albicans is both a commensal and a pathogen at the oral mucosa. Although an intricate network of host defense mechanisms are expected for protection against oropharyngeal candidiasis, anti-Candida host defense mechanisms at the oral mucosa are poorly understood. Our laboratory recently showed that primary epithelial cells from human oral mucosa, as well as an oral epithelial cell line, inhibit the growth of blastoconidia and/or hyphal phases of several Candida species in vitro with a requirement for cell contact and with no demonstrable role for soluble factors. In the present study, we show that oral epithelial cell-mediated anti-Candida activity is resistant to gamma-irradiation and is not mediated by phagocytosis, nitric oxide, hydrogen peroxide, and superoxide oxidative inhibitory pathways or by nonoxidative components such as soluble defensin and calprotectin peptides. In contrast, epithelial cell-mediated anti-Candida activity was sensitive to heat, paraformaldehyde fixation, and detergents, but these treatments were accompanied by a significant loss in epithelial cell viability. Treatments that removed existing membrane protein or lipid moieties in the presence or absence of protein synthesis inhibitors had no effect on epithelial cell inhibitory activity. In contrast, the epithelial cell-mediated anti-Candida activity was abrogated after treatment of the epithelial cells with periodic acid, suggesting a role for carbohydrates. Adherence of C. albicans to oral epithelial cells was unaffected, indicating that the carbohydrate moiety is exclusively associated with the growth inhibition activity. Subsequent studies that evaluated specific membrane carbohydrate moieties, however, showed no role for sulfated polysaccharides, sialic acid residues, or glucose- and mannose-containing carbohydrates. These results suggest that oral epithelial cell-mediated anti-Candida activity occurs exclusively with viable epithelial cells through contact with C. albicans by

  10. Sterical recognition by T4 polynucleotide kinase of non-nucleosidic moieties 5'-attached to oligonucleotides.

    PubMed Central

    Fontanel, M L; Bazin, H; Téoule, R

    1994-01-01

    The ability of T4 polynucleotide kinase (PNK) to phosphorylate non-nucleosidic moieties 5'-attached to oligodeoxynucleotides (ODNs) has been investigated. Non-nucleosidic phosphoramidite units were prepared from ethane-1,2-diol and propane-1,3-diol backbones. Some of them corresponded to pure enantiomers. They were used to obtain the corresponding 5'-end modified oligothymidylates X(pdT)10. The free primary hydroxyl of the non-nucleosidic moieties (X) of these oligomers was phosphorylated by PNK. We report the stereoselective phosphorylation of the L form of the 5'-end attached non-nucleosidic chiral fragments; the non-chiral moieties were completely phosphorylated. Dimers of glycerol analogue and thymidine 3'-phosphate were not recognized by PNK and the shortest modified ODN able to be phosphorylated was a trinucleotide X(pdT)3. A modified X(pdT)10, bearing a cyclic abasic site (X) at its 5'-end, was prepared by chemical synthesis from 1,2-dideoxyribose phosphoramidite and was phosphorylated with a 90% yield. PMID:8029008

  11. 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.

  12. 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.

  13. Fluorescence studies on phenylene moieties embedded in a framework of periodic mesoporous organosilica.

    PubMed

    Okada, Tadashi; Yamanaka, Ken-ichi; Hirose, Yoshiharu; Goto, Yasutomo; Tani, Takao; Inagaki, Shinji

    2011-05-07

    The excited state characteristics of phenylene (Ph)-bridged periodic mesoporous organosilica (PMO) powders with crystal-like and amorphous wall structures are investigated. Crystal-like Ph-PMO has a molecular ordering of the bridging organic moieties with intervals of 0.76 and 0.44 nm parallel and perpendicular to the mesochannel direction, respectively, whereas amorphous Ph-PMO has no molecular-level periodicity in the wall. Fluorescence from the exciton and excimer of the Ph moieties and the defect center in the silicate network were detected at room temperature, but fluorescence from the excimer and the defect center were not detected at 77 K for crystal-like Ph-PMO dispersed in a methanol/ethanol mixed solvent. The decay curve of the exciton fluorescence of crystal-like Ph-PMO at room temperature was analyzed successfully using a one-dimensional diffusion model quenched by the defect center and the excimer site. The results were discussed in comparison with those for the crystal-like biphenylene-bridged PMO reported in the preceding paper (Yamanaka et al., Phys. Chem. Chem. Phys., 2010, 12, 11688-11696). The existence of excited states with various conformations including ground state dimers or aggregates of the Ph moieties was suggested for amorphous Ph-PMO. It was clearly apparent that the differences in the excited state dynamics reflected the differences in the molecular-level structure in the wall. This journal is © the Owner Societies 2011

  14. π-Extended thiadiazoles fused with thienopyrrole or indole moieties: synthesis, structures, and properties.

    PubMed

    Kato, Shin-ichiro; Furuya, Takayuki; Kobayashi, Atsushi; Nitani, Masashi; Ie, Yutaka; Aso, Yoshio; Yoshihara, Toshitada; Tobita, Seiji; Nakamura, Yosuke

    2012-09-07

    We report the syntheses, structures, photophysical properties, and redox characteristics of donor-acceptor-fused π-systems, namely π-extended thiadiazoles 1-5 fused with thienopyrrole or indole moieties. They were synthesized by the Stille coupling reactions followed by the PPh(3)-mediated reductive cyclizations as key steps. X-Ray crystallographic studies showed that isomeric 1b and 2b form significantly different packing from each other, and 1a and 4a afford supramolecular networks via multiple hydrogen bonding with water molecules. Thienopyrrole-fused compounds 1b and 2b displayed bathochromically shifted intramolecular charge-transfer (CT) bands and low oxidation potentials as compared to indole-fused analog 3b and showed moderate to good fluorescence quantum yields (Φ(f)) up to 0.73. In 3b-5b, the introduction of electron-donating substituents in the indole moieties substantially shifts the intramolecular CT absorption maxima bathochromically and leads to the elevation of the HOMO levels. The Φ(f) values of 3-5 (0.04-0.50) were found to be significantly dependent on the substituents in the indole moieties. The OFET properties with 1b and 2b as an active layer were also disclosed.

  15. 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.

  16. Design, Synthesis, and Biological Evaluation of Ganglioside Hp-s1 Analogues Varying at Glucosyl Moiety.

    PubMed

    Hung, Jung-Tung; Yeh, Chun-Hong; Yang, Shih-An; Lin, Chiu-Ya; Tai, Hung-Ju; Shelke, Ganesh B; Reddy, Daggula Mallikarjuna; Yu, Alice L; Luo, Shun-Yuan

    2016-08-17

    Ganglioside Hp-s1 is isolated from the ovary of sea urchin Diadema setosum. It exhibited better neuritogenic activity than GM1 in pheochromocytoma 12 cells. To explore the roles of glucosyl moiety of Hp-s1 in contributing to the neurogenic activity, we developed feasible procedures for synthesis of Hp-s1 analogues (2a-2f). The glucosyl moiety of Hp-s1 was replaced with α-glucose, α-galactose, β-galactose, α-mannose, and β-mannose, and their biological activities on SH-SY5Y cells and natural killer T (NKT) cells were evaluated. We found that the orientation of C-2 hydroxyl group at glucosyl moiety of Hp-s1 plays an important role to induce neurite outgrowth of SH-SY5Y cells. Surprisingly, compound 2d could activate NKT cells to produce interleukin 2, although it did not show great activity on neurite outgrowth of SH-SY5Y cells. In general, the Hp-s1 might be considered as a lead compound for the development of novel drugs aimed at modulating the activity of neuronal cells.

  17. Enrichment of humic material with hydroxybenzene moieties intensifies its physiological effects on the nematode Caenorhabditis elegans.

    PubMed

    Menzel, Ralph; Menzel, Stefanie; Tiedt, Sophie; Kubsch, Georg; Stösser, Reinhardt; Bährs, Hanno; Putschew, Anke; Saul, Nadine; Steinberg, Christian E W

    2011-10-15

    Dissolved humic substances are taken up by organisms and interact on various molecular and biochemical levels. In the nematode Caenorhabditis elegans, such material can promote longevity and increase its reproductive capacity; moreover, the worms tend to stay for longer in humic-enriched environments. Here, we tested the hypothesis that the chemical enrichment of humic substances with hydroxybenzene moieties intensifies these physiological effects. Based on the leonardite humic acid HuminFeed (HF), we followed a polycondensation reaction in which this natural humic substance and a dihydroxybenzene (hydroquinone or benzoquinone) served as reaction partners. Several analytical methods showed the formation of the corresponding copolymers. The chemical modification boosted the antioxidant properties of HF both in vitro and in vivo. Humic substances enriched with hydroxybenzene moieties caused a significantly increased tolerance to thermal stress in C. elegans and extended its lifespan. Exposed nematodes showed delayed linear growth and onset of reproduction and a stronger pumping activity of the pharynx. Thus, treated nematodes act younger than they really are. In this feature the modified HF replicated the biological impact of hydroquinone-homopolymers and various plant polyphenol monomers, thereby supporting the hydroxybenzene moieties of humic substances as major effective structures for the physiological effects observed in C. elegans.

  18. Substituent effects on the properties of photochromic hybrid diarylethenes with a naphthalene moiety.

    PubMed

    Wang, Renjie; Dong, Xiaorong; Pu, Shouzhi; Liu, Gang

    2015-02-25

    Four new unsymmetrical photochromic diarylethenes bearing both naphthalene and thiophene moieties were synthesized, and the structures of two diarylethenes were determined by single-crystal X-ray diffraction analysis. The naphthalene ring was connected directly to the central perfluorocyclopentene ring as an aryl moiety and available to participate in photoisomerization reaction. All the diarylethenes exhibited favorable photochromism and functioned as fluorescence switches in both solution and poly(methyl methacrylate) films. The electron-withdrawing substituent significantly shifted the absorption maxima to a longer wavelength and evidently suppressed the cycloreversion quantum yield, whereas the electron-donating substituents enhanced the fluorescence quantum yield of diarylethenes with a naphthalene moiety. Furthermore, cyclic voltammograms suggested that the oxidation onsets and band-gaps of the open-ring isomers were much bigger than those of the closed-ring isomers. The results indicated that the substituents at the 5-position of thiophene ring could availably modulate their optical and electrochemical behaviors. Copyright © 2014 Elsevier B.V. All rights reserved.

  19. Aglycones and sugar moieties alter anthocyanin absorption and metabolism after berry consumption in weanling pigs.

    PubMed

    Wu, Xianli; Pittman, Hoy E; McKay, Steve; Prior, Ronald L

    2005-10-01

    To investigate the absorption and metabolism of anthocyanins (ACNs) with different aglycones and sugar moieties, weanling pigs (11.4 +/- 3.8 kg) were fed, in a single meal, a freeze-dried powder of chokeberry, black currant, or elderberry at a single dose of 229, 140, or 228 mumol total ACN/kg body weight (BW), respectively. These berries provided ACNs with differences in aglycone as well as some unique differences in the sugar moieties. The relative proportions of the different metabolites depended upon concentrations, quantities consumed, and types of glycoside of ACNs in the berry. Delphinidin ACNs were not metabolized to any measurable extent. Cyanidin ACNs were metabolized via methylation and glucuronidation as well as by formation of both derivatives on the same ACN molecule. ACNs with either a di- or trisaccharide attached to them were excreted in the urine primarily as the intact form. Over 80% of the ACN compounds containing rutinose or sambubiose, which were excreted in the urine from black currant, elderberry, or Marion blackberry, were excreted as the intact molecule. The limited metabolism of these ACNs that did occur was via methylation. ACN monoglycosides other than the glucoside were metabolized via methylation and/or glucuronide formation. The monoglucuronide that formed represented a small proportion of the metabolites relative to the methylated or the mixed methylated and glucuronide forms of ACNs. The data clearly demonstrate that the aglycone and the sugar moieties can alter the apparent absorption and metabolism of ACNs.

  20. AFOSR Technical Report Summaries

    DTIC Science & Technology

    1989-09-01

    The Air Force of Scientific Research Technical Report Summaries are published quarterly of each calendar year. They consist of a brief summary of...each AFOSR technical report received in the Technical Information Division and submitted to the Defense Technical Information Center for that quarter. (sdw)

  1. Correction: Theoretical study and design of multifunctional phosphorescent platinum(ii) complexes containing triarylboron moieties for efficient OLED emitters.

    PubMed

    Wu, Yong; Shan, Guo-Gang; Li, Hai-Bin; Wu, Shui-Xing; Ren, Xin-Yao; Geng, Yun; Su, Zhong-Min

    2015-02-14

    Correction for 'Theoretical study and design of multifunctional phosphorescent platinum(ii) complexes containing triarylboron moieties for efficient OLED emitters' by Yong Wu et al., Phys. Chem. Chem. Phys., 2015, DOI: .

  2. 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

  3. The development of dentotropic micelles with biodegradable tooth-binding moieties.

    PubMed

    Chen, Fu; Jia, Zhenshan; Rice, Kelly C; Reinhardt, Richard A; Bayles, Kenneth W; Wang, Dong

    2013-11-01

    Development of dentotropic (tooth-binding) micelle formulations to improved efficacy and safety of antimicrobial therapy for dental plaque prevention and treatment. Because of their excellent biocompatibility and biodegradability, diphosphoserine peptide and pyrophosphate were selected as the tooth-binding moieties to replace alendronate, which was used previously. Diphosphoserine peptide was conjugated to Pluronic P123 using "click" chemistry, whereas pyrophosphate was attached to P123 through an ester bond. The tooth-binding micelles (TBMs) were prepared by self-assembly of the modified P123 with the antimicrobial agent triclosan. The influence of human saliva and/or its components on TBMs' drug-releasing profile, tooth-binding potential and binding stability was evaluated in vitro. S. mutans UA159 biofilm formed on hydroxyapatite (HA) discs was used to evaluate the TBMs' therapeutic potential. Saliva does not affect triclosan release from TBMs. More than 60% of TBMs' HA binding capacity was maintained in the presence of saliva. Less than 5% of TBMs bound to HA was released over 24 h in human saliva, protease or phosphatase, suggesting the retention properties of the TBMs will not be compromised due to the biodegradable nature of the binding moieties. In both in vitro biofilm prevention and treatment studies, the TBM treated group showed significantly lower CFU per HA disc compared to the controls (2-log reduction, p < 0.05). The data from these studies suggest that the novel dentotropic micelle formulations bearing biodegradable tooth-binding moieties can be used as an effective and safe delivery tool for antimicrobials to improve dental plaque prevention and treatment.

  4. 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.

  5. Synthesis, antifungal and antibacterial activity for novel amide derivatives containing a triazole moiety

    PubMed Central

    2013-01-01

    Background Plant fungi (e.g., Pellicularia sasakii, Gibberella zeae, Fusarium oxysporum, and Cytospora mandshurica and Phytophthora infestans) and bacteria (e.g., Ralstonia solanacearum) are extremely difficult to manage in agricultural production. The high incidence of plant mortality and the lack of effective control methods make P. sasakii and R. solanacearum two of the world’s most destructive plant pathogens. Pathogenic fungi and bacteria are responsible for billions of dollars in economic losses worldwide each year. Thus, we designed an active amide structure and synthesized a series of novel amide derivatives containing a triazole moiety to discover new bioactive molecules and pesticides that can act against fungi and bacteria. Results A series of amide derivatives containing a triazole moiety were synthesized. All the obtained compounds were characterized through proton and carbon nuclear magnetic resonance spectroscopy, infrared spectroscopy, and elemental analysis. Preliminary antifungal activity test showed that some of the synthesized compounds exhibited moderate antifungal activity against P. sasakii, G. azeae, F. oxysporum, C. mandshurica, and P. infestans at 50 mg/L. Compound 4u displayed more potent antifungal activity against P. sasakii and G. azeae than hymexazol. Preliminary antibacterial activity results showed that some of the synthesized compounds exhibited high anti-bacterial activity against R. solanacearum at 200 mg/L. Compounds 4m and 4q displayed high antibacterial activity against R. solanacearum, with 71% and 65% inhibitory rates, respectively. Conclusions A series of novel amide derivatives containing 1,2,4-triazole moiety were synthesized through the reaction of intermediate 3 with different acyl chlorides and anhydrous potassium carbonates in anhydrous tetrahydrofuran at 50°C, using 2,4-dichloroacetophenoneas as a starting material. The title compounds exhibited high inhibitory effects against P. sasakii, R. solanacearum, and G

  6. 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.

  7. 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.

  8. 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.

  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. 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. Copyright © 2014 Elsevier Ltd. All rights reserved.

  13. 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.

  14. 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.

  15. Design, Synthesis, and Antimycobacterial Activity of Novel Theophylline-7-Acetic Acid Derivatives With Amino Acid Moieties.

    PubMed

    Stavrakov, Georgi; Valcheva, Violeta; Voynikov, Yulian; Philipova, Irena; Atanasova, Mariyana; Konstantinov, Spiro; Peikov, Plamen; Doytchinova, Irini

    2016-03-01

    The theophylline-7-acetic acid (7-TAA) scaffold is a promising novel lead compound for antimycobacterial activity. Here, we derive a model for antitubercular activity prediction based on 14 7-TAA derivatives with amino acid moieties and their methyl esters. The model is applied to a combinatorial library, consisting of 40 amino acid and methyl ester derivatives of 7-TAA. The best three predicted compounds are synthesized and tested against Mycobacterium tuberculosis H37Rv. All of them are stable, non-toxic against human cells and show antimycobacterial activity in the nanomolar range being 60 times more active than ethambutol. © 2015 John Wiley & Sons A/S.

  16. 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.

  17. 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

  18. Probing the effect of the solution environment around redox-active moieties using rigid anthraquinone terminated molecular rulers.

    PubMed

    Darwish, Nadim; Eggers, Paul K; Ciampi, Simone; Tong, Yujin; Ye, Shen; Paddon-Row, Michael N; Gooding, J Justin

    2012-11-07

    Herein, we report the influence of the position and the solution environment around surface-bound redox-active moieties on their redox reaction. The study was made possible by using rigid norbornylogous bridges, which possess anthraquinone (AQ) moieties. An L-shaped norbornylogous bridge (L-NB) and straight-shaped norbornylogous bridge (S-NB) were used to situate AQ moieties at well-defined position and environments above a mixed alkanethiol self-assembled monolayer (SAM) on Au (111) surfaces. Sum frequency generation (SFG) vibrational spectroscopy was employed to evaluate the interaction between the S-NB and L-NB with diluent molecules in the mixed SAMs. The SFG measurements demonstrated that hydrogen-bonding interactions were formed between AQ moieties of L-NB and diluent molecules terminated by hydroxyl group within a suitable separation. The SFG observations provided information about the relative position of the AQ moieties in each SAM, which significantly affects the thermodynamics and the kinetics of the electron transfer on the electrode/solution interface. The rate constant (k(et)) of the electron transfer between the AQ moiety and the gold surface and the apparent formal potential (E(0')) were studied using cyclic voltammetry (CV), alternating current voltammetry (ACV), and electrochemical impedance spectroscopy (EIS). It was found that the k(et) increases and E(0') shifts to more anodic values as the distance between the AQ moiety and the surface of the diluent was increased, for both methyl and hydroxyl terminated diluent. These results are discussed in relation to H-bonding interactions with water surrounding the AQ moieties.

  19. 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.

  20. Technical report writing

    NASA Technical Reports Server (NTRS)

    Vidoli, Carol A.

    1992-01-01

    This manual covers the fundamentals of organizing, writing, and reviewing NASA technical reports. It was written to improve the writing skills of LeRC technical authors and the overall quality of their reports.

  1. Technical Assistance Plan (TAP)

    EPA Pesticide Factsheets

    A Technical Assistance Plan (TAP) enables community groups to retain the services of an independent technical advisor and to provide resources for a community group to help inform other community members about site decisions.

  2. BASINS Technical Notes

    EPA Pesticide Factsheets

    EPA has developed several technical notes that provide in depth information on a specific function in BASINS. Technical notes can be used to answer questions users may have, or to provide additional information on the application of features in BASINS.

  3. 2013 Technical Roundtable

    EPA Pesticide Factsheets

    On December 9, 2013, EPA reconvened the study’s Technical Roundtable. Subject-matter experts discussed the outcomes of the 2013 Technical Workshops, stakeholder engagement, and plans for draft assessment report.

  4. 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.

  5. Evidence that the Plant Host Synthesizes the Heme Moiety of Leghemoglobin in Root Nodules1

    PubMed Central

    Santana, Maria A.; Pihakaski-Maunsbach, Kaarina; Sandal, Niels; Marcker, Kjeld A.; Smith, Alison G.

    1998-01-01

    Although it is well established that the plant host encodes and synthesizes the apoprotein for leghemoglobin in root nodules, the source of the heme moiety has been uncertain. We recently found that the transcript for coproporphyrinogen III oxidase, one of the later enzymes of heme synthesis, is highly elevated in soybean (Glycine max L.) nodules compared with roots. In this study we measured enzyme activity and carried out western-blot analysis and in situ hybridization of mRNA to investigate the levels during nodulation of the plant-specific coproporphyrinogen oxidase and four other enzymes of the pathway in both soybean and pea (Pisum sativum L.). We compared them with the activity found in leaves and uninfected roots. Our results demonstrate that all of these enzymes are elevated in the infected cells of nodules. Because these are the same cells that express apoleghemoglobin, the data strongly support a role for the plant in the synthesis of the heme moiety of leghemoglobin. PMID:9536042

  6. 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.

  7. 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.

  8. Synthesis and biological evaluation of some pyrazoline derivatives bearing a dithiocarbamate moiety as new cholinesterase inhibitors.

    PubMed

    Altintop, Mehlika D; Özdemir, Ahmet; Kaplancikli, Zafer A; Turan-Zitouni, Gülhan; Temel, Halide E; Çiftçi, Gülşen A

    2013-03-01

    In the present study, new pyrazoline derivatives were synthesized via the reaction of 1-(chloroacetyl)-3-(2-furyl)-5-aryl-2-pyrazolines with sodium salts of N,N-disubstituted dithiocarbamic acids. Each derivative was evaluated for its ability to inhibit acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) using a modification of Ellman's spectrophotometric method. The compounds were also investigated for their cytotoxic properties using the MTT assay. The most potent AChE inhibitor was found as compound 7 followed by compounds 27 and 17, when compared with eserine. Compounds effective on AChE carry the 2-dimethylaminoethyl moiety, which resembles the trimethylammonium group and the ethylene bridge of acetylcholine. Among all compounds, compound 7 bearing 2-dimethylaminoethyl and 3,4-methylenedioxyphenyl moieties was also found to be the most effective inhibitor of BuChE. The MTT assay indicated that the effective concentration of compound 7 was lower than its cytotoxic concentration. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  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. Scopine as a novel brain-targeting moiety enhances the brain uptake of chlorambucil.

    PubMed

    Wang, Xinyi; Li, Jianbo; Xu, Chaoqun; Li, Yanping; Gong, Tao; Sun, Xun; Fu, Yao; He, Qin; Zhang, Zhirong

    2014-11-19

    The blood brain barrier (BBB) represents the biggest challenge for therapeutic drugs to enter the brain. In our study, we selected chlorambucil (CHL), an alkylating agent, as the model therapeutic agent, and used scopine as a novel brain-targeting moiety. Here, we synthesized Chlorambucil-Scopine (CHLS) prodrug and evaluated its brain-targeting efficacy. The tissue distribution study after i.v. injection revealed that the AUC0-t and Cmax of CHLS in the brain were 14.25- and 12.20-fold of CHL, respectively. Specifically, CHLS accumulated in bEnd.3 and C6 cells in an energy-dependent manner. In C6 cells, superior anti-glioma activity with a significantly decreased IC50 of 65.42 nM/mL was observed for CHLS compared to CHL (IC50 > 400 nM/mL). The safety evaluation, including acute toxicity, pathology, and hematology study, showed minimal toxicity toward nontargeting tissues, and also reached a lower systemic toxicity at 5 mg/kg (i.v.). Our results suggested that scopine is a potential brain-targeting moiety for enhancing the brain uptake efficiency of CHL.

  11. 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

  12. 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

  13. Structure-activity relationship studies of the phytotoxic properties of the diterpenic moiety of breviones.

    PubMed

    Carrera, Ceferino; Chinchilla, Nuria; Fronczek, Frank R; Galindo, Juan C G; Macías, Francisco A

    2015-05-01

    Brevianes are a family of bioactive meroterpenoids originally described in fungi of the family Penicillium. These compounds have attracted a great deal of interest not only because of their unusual skeleton, suggesting a mixed mevalonate and polyketide biogenetic pathway, and their unusual oxa-spiro ring fused to an α-pyrone, but also because of the bioactivities shown by many members of this family. During the course of a project aimed at the total synthesis of natural breviones A to E, the authors were able to synthesise the diterpenic moiety of brevianes and abeo-brevianes. As a result, a collection of 25 compounds were synthesised and tested for bioactivity by two different bioassays. The bioassays used were etiolated wheat coleoptiles (Triticum aestivum) and seedlings in petri dishes. The plant species tested in the seedling bioassay were the commercial dicots lettuce and cress and the monocot weeds Echinochloa crus-galli and Lolium rigidum. The results clearly show that expanded phenanthrene-like compounds corresponding to the diterpenic moiety of abeo-brevianes are more selective towards E. crus-galli in comparison with L. rigidum. Such selectivity can reach up to one order of magnitude (200-fold) and makes some of the compounds good candidates as leads for the development of more specific herbicides. © 2014 Society of Chemical Industry.

  14. Elucidation of the hepatoprotective moiety of 5β-scymnol that suppresses paracetamol toxicity in mice.

    PubMed

    Hodges, Lynn D; Carter, Fiona; Kalafatis, Nicolette; Wright, Paul F A; Macrides, Theodore A

    2016-06-01

    The shark bile alcohol, 5β-scymnol, protects mice from the hepatotoxic effects of paracetamol (APAP) overdose. To elucidate the hepatoprotective structural moiety of scymnol, we compared its effect with that of its analogue and natural bile salt, sodium scymnol sulfate, in a clinically relevant model of APAP-induced toxicity. Exposure of healthy male Swiss mice to a toxic overdose of APAP (350 mg/kg, ip) significantly increased serum hepatocellular enzyme activities, decreased hepatocellular glutathione (GSH) levels, and induced severe centrilobular hepatocellular necrosis. Repeated low-dose scymnol (5 mg/kg/day for 7 days, ip) significantly reduced the extent of APAP-induced hepatotoxicity without preventing GSH depletion. Sodium scymnol sulfate, which lacks the tri-hydroxyl-substituted aliphatic side chain of scymnol, failed to reduce the APAP hepatotoxicity or prevent GSH depletion when tested under the same experimental conditions. We conclude that the tri-hydroxyl-substituted aliphatic side chain is the hepatoprotective structural moiety of 5β-scymnol that suppresses APAP-induced cytotoxicity in mice.

  15. Combinatorial Evaluation of Cations, pH-sensitive and Hydrophobic Moieties for Polymeric Vector Design

    PubMed Central

    Wong, Sharon Y; Sood, Nimil; Putnam, David

    2009-01-01

    Three combinatorial libraries of polymeric vectors were evaluated to investigate the functional roles of molecular weight (MW), cations, pH-sensitive moieties, and hydrophobic derivitization in polymer-mediated gene delivery. Four cationic and pH-sensitive moieties (imidazole, primary, secondary, and tertiary amino) and three hydrophobic residues (C4 butyl, C6 hexyl, and C8 octyl) were assessed in single and serially incremented, binary combinations. Three MWs were evaluated—10, 30, and 50 kDa. The highest levels of transfection, comparable to branched PEI (25 kDa), were achieved by 30 kDa and 50 kDa formulations containing primary amino and imidazole groups. Primary amino groups offered superior charge-neutralizing and size-condensing capacity, while imidazole groups appeared to bind with DNA via nonelectrostatically mediated interactions to produce stable polyplexes that were resistant to premature dissociation. Eight of the 10 highest-transfecting polymers possessed IC50 values greater than the maximum concentration of free polymers exposed to cells (200 µg/ml). The results herein have identified highly efficient polymeric formulations with superb toxicity profiles and have revealed the functional roles that the investigated pendant groups play in the transfection process. The reported polymeric system offers a versatile and robust platform upon which future structure–function studies may be based to create safer and more efficient polymeric vectors. PMID:19142180

  16. Hydrophilization of poly(caprolactone) copolymers through introduction of oligo(ethylene glycol) moieties.

    PubMed

    Wurth, Jonathan J; Blumenthal, Nils R; Shastri, V Prasad

    2014-01-01

    In this study, a new family of poly(ε-caprolactone) (PCL) copolymers that bear oligo(ethylene glycol) (OEG) moieties is described. The synthesis of three different oligo(ethylene glycol) functionalized epoxide monomers derived from 2-methyl-4-pentenoic acid, and their copolymerization with ε-caprolactone (CL) to poly(CL-co-OEG-MPO) copolymers is presented. The statistical copolymerization initiated with SnOct2/BnOH yielded the copolymers with varying OEG content and composition. The linear relationship between feed ratio and incorporation of the OEG co-monomer enables control over backbone functional group density. The introduction of OEG moieties influenced both the thermal and the hydrophilic characteristics of the copolymers. Both increasing OEG length and backbone content resulted in a decrease in static water contact angle. The introduction of OEG side chains in the PCL copolymers had no adverse influence on MC-3TE3-E1 cell interaction. However, changes to cell form factor (Φ) were observed. While unmodified PCL promoted elongated (anisotropic) morphologies (Φ = 0.094), PCL copolymer with tri-ethylene glycol side chains at or above seven percent backbone incorporation induced more isotropic cell morphologies (Φ = 0.184) similar to those observed on glass controls (Φ = 0.151).

  17. Synthetic transformations of a pendant nitrile moiety in group 4 metallocene complexes.

    PubMed

    Pinkas, Jiří; Císařová, Ivana; Kubišta, Jiří; Horáček, Michal; Lamač, Martin

    2013-05-21

    Functional group transformations at the group 4 metallocene framework have been demonstrated, which have provided relatively straightforward access to otherwise synthetically challenging derivatives. The pendant nitrile group in Ti and Zr metallocene complexes of the type [(η(5)-C5Me5)(η(5)-C5H4CMe2CH2CN)MCl2] was converted into an intramolecularly bound ketimido moiety by alkylation, which took place not only at the nitrile, but also at the metal centre. The choice of an alkylating reagent (alkyl/aryl lithium, Grignard reagent) was crucial: e.g., 2 equiv. of MeMgBr effected the alkylation only at the metal, yielding selectively complexes [(η(5)-C5Me5)(η(5)-C5H4CMe2CH2CN)MMe2], while the use of PhMgBr, PhLi, or MeLi instead gave selectively the ketimido complexes. Organyl lithium reagents were, however, not compatible with the titanocene derivatives. The metal-bound ketimides were subsequently cleaved off by the reaction with HCl, which afforded metallocene dichlorides with a pendant imino group. These compounds were easily protonated again at the nitrogen atom to produce a cationic iminium moiety. Aqueous hydrolysis of the imine or its respective hydrochloride proved to be viable in the case of Zr and it finally afforded a pendant ketone group attached to the zirconocene framework.

  18. 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.

  19. Editing Technical Writing.

    ERIC Educational Resources Information Center

    Samson, Donald C., Jr.

    Intended for students in upper-division technical communication courses and professionals in business and government who want to learn how to edit technical writing, this book describes what technical editors do and how they do it. Throughout the book are exercises that students can use as self-tests; answer keys are provided for checking work.…

  20. AFOSR Technical Report Summaries

    DTIC Science & Technology

    1989-06-01

    The Air Force Office of Scientific Research Technical Report Summaries are published quarterly as of March, June, September, and December of each...calendar year. They consist of a brief summary of each AFOSR technical report received in the Technical Information Division and submitted to the Defense

  1. 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.

  2. 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.

  3. Design of antiangiogenic hypoxic cell radiosensitizers: 2-nitroimidazoles containing a 2-aminomethylene-4-cyclopentene-1,3-dione moiety.

    PubMed

    Uto, Yoshihiro; Nagasawa, Hideko; Jin, Cheng-Zhe; Nakayama, Shinichi; Tanaka, Ayako; Kiyoi, Saori; Nakashima, Hitomi; Shimamura, Mariko; Inayama, Seiichi; Fujiwara, Tomoya; Takeuchi, Yoshio; Uehara, Yoshimasa; Kirk, Kenneth L; Nakata, Eiji; Hori, Hitoshi

    2008-06-01

    We designed chiral 2-nitroimidazole derivatives containing a 2-aminomethylene-4-cyclopentene-1,3-dione moiety as antiangiogenic hypoxic cell radiosensitizers. Based on results of molecular orbital calculations, the 2-aminomethylene-4-cyclopentene-1,3-dione moiety is expected to show high electrophilicity comparable to that of the 2-methylene-4-cyclopentene-1,3-dione moiety included in TX-1123 and tyrphostin AG17. We evaluated the antiangiogenic and radiosensitizing effects of the new compounds, along with other biological properties including their activities as hypoxic cytotoxicities and protein tyrosine kinase (PTK) inhibitory activities. Among the compounds tested, 5 (TX-2036) proved to be the strongest antiangiogenic hypoxic cell radiosensitizer. All the other chiral 2-nitroimidazole derivatives having 2-aminomethylene-4-cyclopentene-1,3-dione moiety tested were also antiangiogenic hypoxic cell radiosensitizers. The PTK inhibitory activity of 5 (TX-2036) showed this to be a promising and potent EGFR kinase inhibitor, having an IC(50) value of lower than 2microM. This compound also was an Flt-1 kinase inhibitor having an IC(50) value of lower than 20microM. Our results show that these chiral 2-nitroimidazole derivatives that contain the 2-aminomethylene-4-cyclopentene-1,3-dione moiety as a potent antiangiogenic pharmacophoric descriptor are promising lead candidates for the development of antiangiogenic hypoxic cell radiosensitizers.

  4. Difference of carboxybetaine and oligo(ethylene glycol) moieties in altering hydrophobic interactions: a molecular simulation study.

    PubMed

    Shao, Qing; White, Andrew D; Jiang, Shaoyi

    2014-01-09

    Polycarboxybetaine and poly(ethylene glycol) materials resist nonspecific protein adsorption but differ in influencing biological functions such as enzymatic activity. To investigate this difference, we studied the influence of carboxybetaine and oligo(ethylene glycol) moieties on hydrophobic interactions using molecular simulations. We employed a model system composed of two non-polar plates and studied the potential of mean force of plate-plate association in carboxybetaine, (ethylene glycol)4, and (ethylene glycol)2 solutions using well-tempered metadynamics simulations. Water, trimethylamine N-oxide, and urea solutions were used as reference systems. We analyzed the variation of the potential of mean force in various solutions to study how carboxybetaine and oligo(ethylene glycol) moieties influence the hydrophobic interactions. To study the origin of their influence, we analyzed the normalized distributions of moieties and water molecules using molecular dynamics simulations. The simulation results showed that oligo(ethylene glycol) moieties repel water molecules away from the non-polar plates and weaken the hydrophobic interactions. Carboxybetaine moieties do not repel water molecules away from the plates and therefore do not influence the hydrophobic interactions.

  5. A novel diarylheptanoid-bearing sesquiterpene moiety from the rhizomes of Alpinia officinarum.

    PubMed

    Wei, Na; Zhou, Zhonglin; Wei, Qing; Wang, Yong; Jiang, Jun; Zhang, Junqing; Wu, Lixiang; Dai, Shuiping; Li, Youbin

    2016-10-01

    A new diarylheptanoid analogue-bearing sesquiterpene moiety, named Alpinisin A, was isolated from the rhizomes of Alpinia officinarum Hance. The new structure was determined by various spectroscopic techniques (1)H-nuclear magnetic resonance ((1)H NMR), (13)C-attached proton test ((13)C-APT), heteronuclear single quantum coherence (HSQC), heteronuclear multiple bond correlation (HMBC), (1)H-(1)H correlation spectroscopy ((1)H-(1)HCOSY), nuclear overhauser effect spectroscopy (NOESY) and high resolution electrospray ionization mass spectrometry (HR-ESI-MS). The compound was tested for cytotoxic activity in vitro against human tumour cell lines (gastric carcinoma cell -7901 (SGC-7901), Michigan Cancer Foundation-7 (MCF-7) and Caski), which showed significant inhibitory effects with IC50 levels of 11.42, 15.14 and 14.78 μM, respectively. The novel chemical structure characterised with a diarylheptanoid linked to a chain-like sesquiterpenoid should be highlighted.

  6. 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

  7. Self-Assembled Fibers Containing Stable Organic Radical Moieties: Alignment and Magnetic Properties in Liquid Crystals.

    PubMed

    Eimura, Hiroki; Umeta, Yoshikazu; Tokoro, Hiroko; Yoshio, Masafumi; Ohkoshi, Shin-Ichi; Kato, Takashi

    2016-06-20

    Macroscopically oriented stable organic radicals have been obtained by using a liquid-crystalline (LC) gel composed of an l-isoleucine-based low molecular weight gelator containing a 2,2,6,6-tetramethylpiperidine 1-oxyl moiety. The LC gel has allowed magnetic measurements of the oriented organic radical. The gelator has formed fibrous aggregates in liquid crystals via intermolecular hydrogen bonds. The fibrous aggregates of the radical gelator are formed and oriented on cooling by applying a magnetic field to the mixture of liquid crystals and the gelator. Superconducting quantum interference device (SQUID) measurements have revealed that both oriented and nonoriented fibrous aggregates exhibited antiferromagnetic interactions, in which super-exchange interaction constant J is estimated as -0.89 cm(-1) . © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  8. Potent DGAT1 Inhibitors in the Benzimidazole Class with a Pyridyl-oxy-cyclohexanecarboxylic Acid Moiety

    PubMed Central

    2013-01-01

    We report the design and synthesis of a series of novel DGAT1 inhibitors in the benzimidazole class with a pyridyl-oxy-cyclohexanecarboxylic acid moiety. In particular, compound 11A is a potent DGAT1 inhibitor with excellent selectivity against ACAT1. Compound 11A significantly reduces triglyceride excursion in lipid tolerance tests (LTT) in both mice and dogs at low plasma exposure. An in vivo study in mice with des-fluoro analogue 10A indicates that this series of compounds appears to distribute in intestine preferentially over plasma. The propensity to target intestine over plasma could be advantageous in reducing potential side effects since lower circulating levels of drug are required for efficacy. However, in the preclinical species, compound 11A undergoes cis/trans epimerization in vivo, which could complicate further development due to the presence of an active metabolite. PMID:24900745

  9. 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.

  10. Design, synthesis, and biological activity of oxime ether strobilurin derivatives containing indole moiety as novel fungicide.

    PubMed

    Xie, Ya-Qiang; Huang, Zi-Long; Yan, Hui-Dong; Li, Jun; Ye, Li-Yi; Che, Li-Ming; Tu, Song

    2015-06-01

    Twenty-one novel oxime ether strobilurins containing indole moiety, which employed an indole group to stabilize the E-styryl group in Enoxastrobin, were designed and synthesized. The biological assay indicated that most compounds exhibited potent fungicidal activities. The structure-activity relationship study demonstrated that the synthesized methyl 3-methoxypropenoate oxime ethers 7b-e exhibited remarkably high activities among all the synthesized oxime ether compounds 7. Moreover, the fungicidal activities of methyl α-(methoxyimino)benzeneacetate oxime ethers compounds 7f-i and N-methoxy-carbamic acid methyl esters compounds 7j-m showed significant differences compared to the corresponding products of ammonolysis. © 2014 John Wiley & Sons A/S.

  11. Synthesis and Pharmacological Evaluation of Novel Pleuromutilin Derivatives with Substituted Benzimidazole Moieties.

    PubMed

    Ai, Xin; Pu, Xiuying; Yi, Yunpeng; Liu, Yu; Xu, Shuijin; Liang, Jianping; Shang, Ruofeng

    2016-11-08

    A series of novel pleuromutilin derivatives with substituted benzimidazole moieties were designed and synthesized from pleuromutilin and 5-amino-2-mercaptobenzimidazole through sequential reactions. All the newly synthesized compounds were characterized by IR, NMR, and HRMS. Each of the derivatives was evaluated in vitro for their antibacterial activity against Escherichia coli (E. coli) and five Gram (+) inoculums. 14-O-((5-amino-benzimidazole-2-yl) thioacetyl) mutilin (3) was the most active compound and showed highest antibacterial activities. Furthermore, we evaluated the inhibition activities of compound 3 on short-term S. aureus and MRSA growth and cytochrome P450 (CYP). The bioassay results indicate that compound 3 could be considered potential antibacterial agents but with intermediate inhibition of CYP3A4.

  12. Synthesis and evaluation of novel pleuromutilin derivatives with a substituted pyrimidine moiety.

    PubMed

    Yi, Yunpeng; Yang, Guanzhou; Zhang, Chao; Chen, Jiongran; Liang, Jianping; Shang, Ruofeng

    2015-08-28

    A series of novel pleuromutilin derivatives possessing 6-hydroxy pyrimidine moieties were synthesized via acylation reactions under mild conditions. The in vitro antibacterial activities of the synthesized derivatives against methicillin-resistant Staphylococcus aureus (MRSA), methicillin-resistant Staphylococcus epidermidis (MRSE), Bacillus subtilis (B. subtilis), and Escherichia coli (E. coli) were tested by the agar dilution method. The majority of the screened compounds displayed potent activities. Compounds 3 and 6a were found to be the most active antibacterial agents against MRSA and MRSE. Moreover, in the vivo experiment, compound 6a showed comparable antibacterial activity to that of tiamulin, with ED50 of 5.47 mg/kg body weight against MRSA. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

  13. Synthesis of bifunctional receptor for fluoride and cadmium based on calix[4]arene with thiourea moieties

    NASA Astrophysics Data System (ADS)

    Quiroga-Campano, C.; Gómez-Machuca, H.; Moris, S.; Jara, P.; De la Fuente, J. R.; Pessoa-Mahana, H.; Jullian, C.; Saitz, C.

    2017-08-01

    A new calix[4]arene thiourea derivative bearing a benzothiazolyl moiety (L) was synthetized and characterized by single crystal X-ray, NMR and ESI-TOF. The binding ability of the bifunctional receptor towards several ions was investigated in acetonitrile by means of UV-Visible and NMR spectroscopy. The UV-Vis studies of receptor L demonstrated a stoichiometry of 1:1 for all ions studied. Also, recognize selectively F- and Cd2+ with a detection limit of 97 and 37 μM, respectively. Also, 1H NMR titration of receptor L indicated that both thiourea bridge and phenolic hydroxyl functional groups played a critical role in the binding of F- and Cd2+ ions. 1H NMR spectrum showed that receptor L has a flattened-cone conformation in solution that changes to a cone conformation in the presence of fluoride while cadmium maintained the initial conformation.

  14. 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.

  15. 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.

  16. The Biosynthesis of the Pyrimidine Moiety of Thiamin in Halobacterium salinarum.

    PubMed

    Kijima, Yukie; Hayashi, Maria; Yamada, Kazuko; Tazuya-Murayama, Keiko

    2016-01-01

    The biosynthetic pathway of the pyrimidine moiety of thiamin was studied in the archaean Halobacterium salinarum. Thiamin is biosynthesized from 4-amino-5-hydroxymethyl-2-methylpyrimidine (pyrimidine) and 5-(2-hydroxyethyl)-4-methylthiazole (thiazole). The pyrimidine and the thiazole are biosynthesized de novo in microorganisms. The biosynthetic routes of pyrimidine in microorganisms differ between eukaryote and eubacteria. In the eukaryote Saccharomyces cerevisiae, histidine and pyridoxine are the precursors of pyrimidine, while in the eubacterium Escherichia coli, pyrimidine is biosynthesized from 5-aminoimidazole ribonucleotide (AIR), an intermediate of purine biosynthesis. Tracer investigations revealed that [(15)N]-, [1-(13)C]- and [2-(13)C] glycine, precursors of AIR, were incorporated into the pyrimidine in H. salinarum. These results suggested that the biosynthetic route of the pyrimidine in H. salinarum is similar to that of E. coli.

  17. Experimental and theoretical insight into the complexation behavior of spironaphthopyrans bearing o-positioning benzazole moiety

    NASA Astrophysics Data System (ADS)

    Rostovtseva, I. A.; Chernyshev, A. V.; Tkachev, V. V.; Dorogan, I. V.; Voloshin, N. A.; Solov'eva, E. V.; Metelitsa, A. V.; Gaeva, E. B.; Aldoshin, S. M.; Minkin, V. I.

    2017-10-01

    Metal coordination by spironaphthopyran derived merocyanines bearing benzazol substituents has been studied by means of experimental and theoretical methods. The formation of N-O coordinated chelate complexes have been observed by means of X-ray diffraction. Merocyanine scaffolds of these complexes possess trans-trans-cis conformation independently of both substituents in positions 1 and 5 of indoline moiety and benzazole heteroatom. Stability of merocyanine-metal complexes significantly depends on two factors: relative thermodynamic stability of spirocyclic and open isomers and complexation energy. Variation of the ligand structure involving chelating group significantly changes stability of complexes while replacement of the substituents in the indoline ring peripheral to the chelating parts of the molecules and biasing the spiropyran - merocyanine equilibrium provide the fine tuning of complexation selectivity. Complexes of diamagnetic ions (Mg2+, Zn2+, Cd2+) undergo photodissociation. The complexes of benzoxazole containing ligands demonstrate higher quantum yields comparing to their benzothiazole analogue.

  18. 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.

  19. 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.

  20. Biosynthetic studies on ansatrienin A. Formation of the cyclohexanecarboxylic acid moiety

    SciTech Connect

    Moore, B.S.; Kennedy, E.; Reynolds, K.A. ); Cho, H.; Mocek, U.; Beale, J.M.; Floss, H.G. Ohio State Univ., Columbus ); Casati, R. )

    1993-06-16

    The formation of the cyclohexanecarboxylic acid moiety in the biosynthesis of ansatrienin (mycotrienin) has been studied. [sup 13]C- and [sup 2]H-labeled samples of shikimic acid were used to probe the stereochemistry of processing the cyclohexane ring of shikimic acid and to establish the fate of all the precursor hydrogens in this transformation. A sample of [2-[sup 13]C]shikimic acid was fed to Streptomyces collinus Tu 1982, and [sup 13]C in the resulting ansatrienin was found to reside exclusively at C-36. The l-cyclohexenecarboxylic acid accompanying the cyclohexanecarboxylic acid in the hydrolysis of the biosynthetic sample of ansatrienin carried the [sup 13]C label not at C-2 but at C-6. Samples of [2-[sup 2]H]-, [3-[sup 2]H]-, [4-[sup 2]H], [2,5-[sup 2]H[sub 2

  1. Amphiphilic polymers bearing gluconolactone moieties: synthesis and long side-chain crystalline behavior.

    PubMed

    Cerrada, María L; Bordegé, Vanesa; Muñoz-Bonilla, Alexandra; León, Orietta; Cuervo-Rodríguez, Rocío; Sánchez-Chaves, Manuel; Fernández-García, Marta

    2013-05-15

    The synthesis and characterization of amphiphilic polymers bearing gluconolactone moieties has been described. In a first step, an unprotected glycomonomer 2-[({[4-(d-gluconamid-N-yl)butyl]amino}carbonyl)oxy]ethyl acrylate, HEAG, has been synthesized. Posterior, this glycomonomer has been copolymerized with methyl methacrylate at different compositions and the kinetic behavior has been also studied calculating the monomer reactivity ratios by Kelen-Tüdös extended equation. In addition, the long side-chain crystalline behavior of these carbohydrate-based copolymers with high composition of glycomonomer has been examined by using conventional and modulated differential scanning calorimetry and X-ray diffraction measurements. At the same time, the phase separation behavior of carbohydrate-based copolymers with lower HEAG content has been determined by their glass transition temperature measurements. Finally, the thermal stability of all these amphiphilic copolymers has been evaluated by thermogravimetric analysis. Copyright © 2013 Elsevier Ltd. All rights reserved.

  2. 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

  3. 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

  4. Potent DGAT1 Inhibitors in the Benzimidazole Class with a Pyridyl-oxy-cyclohexanecarboxylic Acid Moiety.

    PubMed

    He, Shuwen; Hong, Qingmei; Lai, Zhong; Wu, Zhicai; Yu, Yang; Kim, David W; Ting, Pauline C; Kuethe, Jeffrey T; Yang, Ginger X; Jian, Tianying; Liu, Jian; Guiadeen, Deodial; Krikorian, Arto D; Sperbeck, Donald M; Sonatore, Lisa M; Wiltsie, Judyann; Chung, Christine C; Gibson, Jack T; Lisnock, JeanMarie; Murphy, Beth A; Gorski, Judith N; Liu, Jinqi; Chen, Dunlu; Chen, Xiaoli; Wolff, Michael; Tong, Sharon X; Madeira, Maria; Karanam, Bindhu V; Shen, Dong-Ming; Balkovec, James M; Pinto, Shirly; Nargund, Ravi P; DeVita, Robert J

    2013-08-08

    We report the design and synthesis of a series of novel DGAT1 inhibitors in the benzimidazole class with a pyridyl-oxy-cyclohexanecarboxylic acid moiety. In particular, compound 11A is a potent DGAT1 inhibitor with excellent selectivity against ACAT1. Compound 11A significantly reduces triglyceride excursion in lipid tolerance tests (LTT) in both mice and dogs at low plasma exposure. An in vivo study in mice with des-fluoro analogue 10A indicates that this series of compounds appears to distribute in intestine preferentially over plasma. The propensity to target intestine over plasma could be advantageous in reducing potential side effects since lower circulating levels of drug are required for efficacy. However, in the preclinical species, compound 11A undergoes cis/trans epimerization in vivo, which could complicate further development due to the presence of an active metabolite.

  5. 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

  6. Synthesis, antimycobacterial and antibacterial activity of ciprofloxacin derivatives containing a N-substituted benzyl moiety.

    PubMed

    Wang, Shuo; Jia, Xue-Dong; Liu, Ming-Liang; Lu, Yu; Guo, Hui-Yuan

    2012-09-15

    We report herein the design and synthesis of a series of novel ciprofloxacin (CPFX) derivatives with remarkable improvement in lipophilicity by introducing a substituted benzyl moiety to the N atom on the C-7 piperazine ring of CPFX. Antimycobacterial and antibacterial activity of the newly synthesized compounds was evaluated. Results reveal that compound 4f has good in vitro activity against all of the tested Gram-positive strains including MRSA and MRSE (MICs: 0.06-32 μg/mL) which is two to eightfold more potent than or comparable to the parent drug CPFX (MICs: 0.25-128 μg/mL), Gram-negative bacteria P. aeruginosa (MICs: 0.5-4 μg/mL) and M. tuberculosis H37Rv ATCC 27294 (MIC: 1 μg/mL). Copyright © 2012 Elsevier Ltd. All rights reserved.

  7. 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.

  8. Mesoporous silicas with covalently immobilized β-cyclodextrin moieties: synthesis, structure, and sorption properties

    NASA Astrophysics Data System (ADS)

    Roik, Nadiia V.; Belyakova, Lyudmila A.; Trofymchuk, Iryna M.; Dziazko, Marina O.; Oranska, Olena I.

    2017-09-01

    Mesoporous silicas with chemically attached macrocyclic moieties were successfully prepared by sol-gel condensation of tetraethyl orthosilicate and β-cyclodextrin-silane in the presence of a structure-directing agent. Introduction of β-cyclodextrin groups into the silica framework was confirmed by the results of IR spectral, thermogravimetric, and quantitative chemical analysis of surface compounds. The porous structure of the obtained materials was characterized by nitrogen adsorption-desorption measurements, powder X-ray diffraction, transmission electron microscopy, and dynamic light scattering. It was found that the composition of the reaction mixture used in β-cyclodextrin-silane synthesis significantly affects the structural parameters of the resulting silicas. The increase in (3-aminopropyl)triethoxysilane as well as the coupling agent content in relation to β-cyclodextrin leads ultimately to the lowering or complete loss of hexagonal arrangement of pore channels in the synthesized materials. Formation of hexagonally ordered mesoporous structure was observed at molar composition of the mixture 0.049 TEOS:0.001 β-CD-silane:0.007 CTMAB:0.27 NH4OH:7.2 H2O and equimolar ratio of components in β-CD-silane synthesis. The sorption of alizarin yellow on starting silica and synthesized materials with chemically attached β-cyclodextrin moieties was studied in phosphate buffer solutions with pH 7.0. Experimental results of the dye equilibrium sorption were analyzed using Langmuir, Freundlich, and Redlich-Peterson isotherm models. It was proved that the Redlich-Peterson isotherm model is the most appropriate for fitting the equilibrium sorption of alizarin yellow on parent silica with hexagonally arranged mesoporous structure as well as on modified one with chemically immobilized β-cyclodextrin groups. [Figure not available: see fulltext.

  9. New photosensitizers containing the dipyridoquinoxaline moiety and their use in dye-sensitized solar cells.

    PubMed

    Shahroosvand, Hashem; Rezaei, Shiva; Abbaspour, Saeid

    2015-11-01

    New Ru(II) polypyridyl complexes containing two N, N bidentate ligands, [Ru(phendione)2dpq(COOH)2](BF4)2 (L101), {Ru(phendione)[dpq(COOH)2]2}(BF4)2 (L102) and [Ru(phendione)dpq(COOH)2 (SCN)2](L103), (phendione=5,6 dione-1,10-phenanthroline and dpq(COOH)2=6,7-dicarboxylicdipyrido[2,2-d:2',3'f]quinoxaline) have been synthesized and characterized, and attached to a TiO2 substrate to be tested as solar cell sensitizers. We found that the solar to electricity conversion efficiency of cell is strongly affected by the type of ancillary ligand, the efficiency of L102 (with one phendione moiety) adsorbed on TiO2 nanocrystalline films being 2.5 times as large as that of L101 (with two phendione moieties) adsorbed on the same films. The effect of ancillary ligand on the photovoltaic performance of the complexes was compared to results of computational methods by ab initio DFT molecular dynamics simulations and quantum dynamics calculations of electronic relaxation to investigate the interfacial electron transfer in L101-103/TiO2-anatase nanostructures. It is found that the primary process in the interfacial electron-transfer dynamics involves an ultrafast (τ1=6 fs) electron-injection. The concepts of attribute ancillary ligand substitution and HOMO-LUMO alignment of dye with conduction band of semiconductor and electrolyte redox state are shown very helpful for tuning the photovoltaic properties and the rational architecture of polypyridyl photosensitizer with anticipated good properties.

  10. 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. Copyright © 2014 Elsevier Inc. All rights reserved.

  11. 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.

  12. 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.

  13. High-performance liquid chromatography estimation of cross-linking of dihydroxyindole moiety in eumelanin.

    PubMed

    Ito, Shosuke; Wakamatsu, Kazumasa; Glass, Keely; Simon, John D

    2013-03-15

    Eumelanin pigments consist of various ratios of 5,6-dihydroxyindole-2-carboxylic acid (DHICA) and 5,6-dihydroxyindole (DHI). On alkaline hydrogen peroxide oxidation, these indole moieties give rise to pyrrole-2,3,5-tricarboxylic acid (PTCA) and pyrrole-2,3-dicarboxylic acid (PDCA), respectively. In a recent study, we detected considerable amounts of other pyrrole acids, pyrrole-2,3,4,5-tetracarboxylic acid (PTeCA) and pyrrole-2,3,4-tricarboxylic acid (isoPTCA), among the oxidation products of fossil ink sacs more than 160 million years old. PTeCA and isoPTCA arise from the cross-linking of the DHI moiety of eumelanin at the C2 and/or C3 positions. We mimicked the process of cross-linking by heating synthetic eumelanins prepared from various ratios of DHICA and DHI at 100 °C for 18 days (or at 40 °C for 180 days). The heated eumelanins were analyzed after alkaline peroxide oxidation as PTCA, PDCA, PTeCA, and isoPTCA by high-performance liquid chromatography (HPLC) with ultraviolet (UV) detection. On heating, PTCA decreased rapidly due to decarboxylation, whereas PDCA decreased gradually. Concurrently, PTeCA increased gradually to levels close to PTCA. IsoPTCA also increased gradually at lower levels. Similar changes were observed at 40°C at a much slower rate. These findings suggest that the PTeCA/PTCA ratio may serve as a good indicator of aging (cross-linking) of eumelanin. Copyright © 2012 Elsevier Inc. All rights reserved.

  14. Hydroxylamine moiety of developmental toxicants is associated with early cell death: a structure-activity analysis.

    PubMed

    DeSesso, J M; Jacobson, C F; Scialli, A R; Goeringer, G C

    2000-11-01

    Cellular debris, an indicator of cell death, appears in limb buds of gestational day 12 rabbit embryos 4 hr after either a subcutaneous injection of hydroxyurea to pregnant rabbits or an injection of hydroxyurea into the exocoelomic cavities of the embryos. This episode of early cell death appears to be central to the teratogenic action of hydroxyurea. Several chemicals that are structurally related to hydroxyurea, and that possess a terminal hydroxylamine moiety (-NHOH), also produce limb abnormalities. To investigate whether the hydroxylamine moiety is responsible for early cell death and, therefore, is likely to be associated with teratogenesis, five structurally related hydroxylamine-bearing chemicals (hydroxylamine hydrochloride, N-methylhydroxylamine hydrochloride, hydroxyurea, acetohydroxamic acid, and hydroxyurethane) were administered at equimolar doses to rabbits either by subcutaneous (8.55 mmol/kg) or intracoelomic (2.66 micromol/embryo) injection on gestational day 12. Five additional chemicals, structurally similar to the hydroxylamine-bearing compounds, but possessing a terminal amino group (-NH(2)) (ammonium hydroxide, methylamine, urea, acetamide, and urethane), were tested at equimolar or higher doses by an identical protocol. In a subsequent experiment, the antioxidant propyl gallate (3.0 mmol/kg or 1.30 micromol/embryo) was co-administered with the hydroxylamine-bearing compounds to determine its effect on early cell death. Embryos were harvested 4 or 8 hr after treatment and analyzed by light microscopy. Cellular debris was obvious in forelimb buds from embryos treated with the hydroxylamine-bearing compounds; however, none of the amino compounds produced an early episode of embryonic cell death. In all cases, the antioxidant propyl gallate prevented or delayed the early episode of cell death observed after treatment with the hydroxylamine-bearing compounds. These results are consistent with the concept that the rapidly occurring embryonic

  15. 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.

  16. 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.

  17. Datacomputer Project Technical Report

    DTIC Science & Technology

    1974-02-28

    34IM " "■ mmmam DATACOMPUTER PROJECT TECHNICAL REPORT Computer Corporation of America AD/A-002 083 Prepared for: Army Research Office...021 Computer Corporation of America 575 Technology Square Cambridge, Massachusetts Ü2139 0 DATACOMPUTER PROJECT TECHNICAL REPORT August 1...applications and user programs. The present document is the final technical report under Contract No. DAHC04-71-C-0Q11. The project is continuing

  18. Inhibition of β-carbonic anhydrases from Brucella suis with C-cinnamoyl glycosides incorporating the phenol moiety.

    PubMed

    Riafrecha, Leonardo E; Vullo, Daniela; Ouahrani-Bettache, Safia; Köhler, Stephan; Dumy, Pascal; Winum, Jean-Yves; Supuran, Claudiu T; Colinas, Pedro A

    2015-12-01

    A small series of C-glycosides containing the phenol moiety was tested for the inhibition of the β-class carbonic anhydrases (βCAs, EC 4.2.1.1) from Brucella suis. Many compounds showed activities in the micromolar or submicromolar range and excellent selectivity for pathogen CAs over human isozymes. Glycosides incorporating the 3-hydroxyphenyl moiety showed the best inhibition profile, and therefore this functionality represents lead for the development of novel anti-infectives with a new mechanism of action.

  19. Synthesis of analogues of the O-beta-D-ribofuranosyl nucleoside moiety of liposidomycins. Part 1: contribution of the amino group and the uracil moiety upon the inhibition of MraY.

    PubMed

    Dini, C; Drochon, N; Feteanu, S; Guillot, J C; Peixoto, C; Aszodi, J

    2001-02-26

    The O-beta-D-ribofuranosyl nucleoside I is the minimal structural entity of liposidomycins maintaining enzyme inhibitory activity. Modifications performed on both the primary amine and the uracil moieties clearly demonstrate their major contribution to the inhibition of the bacterial translocase (MraY).

  20. Technical Mathematics: Restructure of Technical Mathematics.

    ERIC Educational Resources Information Center

    Flannery, Carol A.

    Designed to accompany a series of videotapes, this textbook provides information, examples, problems, and solutions relating to mathematics and its applications in technical fields. Chapter I deals with basic arithmetic, providing information on fractions, decimals, ratios, proportions, percentages, and order of operations. Chapter II focuses on…

  1. Technical Mathematics: Restructure of Technical Mathematics.

    ERIC Educational Resources Information Center

    Flannery, Carol A.

    Designed to accompany a series of videotapes, this textbook provides information, examples, problems, and solutions relating to mathematics and its applications in technical fields. Chapter I deals with basic arithmetic, providing information on fractions, decimals, ratios, proportions, percentages, and order of operations. Chapter II focuses on…

  2. Technical Education Curriculum Assessment

    ERIC Educational Resources Information Center

    Keiser, Jonathan C.; Lawrenz, Frances; Appleton, James J.

    2004-01-01

    The purpose of this paper is to describe and determine the efficacy of a Technical Education Curriculum Assessment (TECA). The TECA was designed to guide the judgment of the quality of technical education curricular materials. Three research strands were combined into a theoretical framework which underlies the education of effective technicians.…

  3. Scientific and Technical English.

    ERIC Educational Resources Information Center

    Vaclavik, Jaroslav

    Technical English differs from everyday English because of the specialized contexts in which it is used and because of the specialized interests of scientists and engineers. This text provides exercises in technical and scientific exposition in the following fields: mathematics, physics, temperature effects, mechanics, dynamics, conservation of…

  4. Technical Training for Managers.

    ERIC Educational Resources Information Center

    Haverland, Edgar M.

    The question has arisen as to what kind of information a manager without extensive technical training needs to learn to supervise effectively. For example, the Nike Hercules fire control platoon leader, usually an officer in his first active duty assignment, seldom has had extensive technical training. Yet he is responsibile for the…

  5. Technical and Vocational Training.

    ERIC Educational Resources Information Center

    Vocational Training, 1993

    1993-01-01

    This issue focuses on the various forms that secondary technical and vocational education takes in different European Community Member States. "The Future for Skilled Workers" is an interview with Burkart Lutz, a German researcher. Other articles are as follows: "Contradictions in Technical and Vocational Education: The…

  6. Developing Technical Skill Assessments

    ERIC Educational Resources Information Center

    Hyslop, Alisha

    2009-01-01

    One of the biggest challenges facing the career and technical education (CTE) community as it works to implement the 2006 Perkins Act is responding to more rigorous requirements for reporting on CTE students' technical skill attainment. The U.S. Department of Education suggested in non-regulatory guidance that states and locals use the number of…

  7. Technical Manual. The ACT®

    ERIC Educational Resources Information Center

    ACT, Inc., 2014

    2014-01-01

    This manual contains technical information about the ACT® college readiness assessment. The principal purpose of this manual is to document the technical characteristics of the ACT in light of its intended purposes. ACT regularly conducts research as part of the ongoing formative evaluation of its programs. The research is intended to ensure that…

  8. Annual Technical Report.

    DTIC Science & Technology

    1982-11-01

    T ’ .. . . . -. . . . , . . . - . ... - -. --- ~ . . . ..... .... IIS~ANNUAL TECHNICAL REPORT K-TO THE OFFICE OF NAVAL RESEARCH CONTRACT No, N00014...RIECIPICHT’S CATC1.O@ NUM@SA 4. TITLE (sn$ S-611fleI) ’I TYPE OP RErPORT A Pimo0o COVEREC, Annual Technical Report Am~4~10/01ZS-9130/26 S.PERFORMING

  9. Research in Technical Colleges

    ERIC Educational Resources Information Center

    MacLennan, A.

    2008-01-01

    Purpose: The purpose of this paper is to list and demonstrate areas in which research needs to be carried out, or questions answered, in order to raise the quality of technical education. Design/methodology/approach: The area of technical education expanded very rapidly in the late 1950s, and there was little comprehensive knowledge regarding the…

  10. Technical Training for Managers.

    ERIC Educational Resources Information Center

    Haverland, Edgar M.

    The question has arisen as to what kind of information a manager without extensive technical training needs to learn to supervise effectively. For example, the Nike Hercules fire control platoon leader, usually an officer in his first active duty assignment, seldom has had extensive technical training. Yet he is responsibile for the…

  11. Scientific and Technical English.

    ERIC Educational Resources Information Center

    Vaclavik, Jaroslav

    Technical English differs from everyday English because of the specialized contexts in which it is used and because of the specialized interests of scientists and engineers. This text provides exercises in technical and scientific exposition in the following fields: mathematics, physics, temperature effects, mechanics, dynamics, conservation of…

  12. 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

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

    PubMed

    van Rossum, Harmen M; Kozak, Barbara U; Niemeijer, Matthijs S; Dykstra, James C; Luttik, Marijke A H; Daran, Jean-Marc G; van Maris, Antonius J A; Pronk, Jack T

    2016-05-03

    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. This study demonstrates, for the first time, that Saccharomyces cerevisiae can be engineered to employ the carnitine shuttle for export of acetyl moieties from the mitochondria and, thereby, to act as the sole source of cytosolic acetyl-CoA. Further optimization of this ATP-independent mechanism for cytosolic acetyl-CoA provision can contribute to efficient

  14. Monomeric and dimeric nickel complexes derived from a pincer ligand featuring a secondary amine donor moiety.

    PubMed

    Spasyuk, Denis M; Zargarian, Davit

    2010-07-05

    Reaction of NiBr(2)(CH(3)CN)(x) with the unsymmetrical pincer ligand m-(i-Pr(2)PO)(CH(2)NHBn)C(6)H(4) (Bn = CH(2)Ph) gives the complex (R,S)-kappa(P),kappa(C),kappa(N)-{2-(i-Pr(2)PO),6-(CH(2)NHBn)-C(6)H(3)}Ni(II)Br, 1, featuring an asymmetric secondary amine donor moiety. Deprotonation of the latter with methyl lithium gave a dark brown compound that could not be characterized directly, but fully characterized derivatives prepared from this compound indicate that it is the LiBr adduct of the 14-electron amido species [kappa(P),kappa(C),kappa(N)-{2-(i-Pr(2)PO),6-(CH(2)NBn)-C(6)H(3)}Ni], 2. Thus, 2.LiBr reacts with water to regenerate 1, while reaction with excess benzyl or allyl bromide gave the POCN-type pincer complexes 3 and 4, respectively, featuring tertiary amine donor moieties. On the other hand, heating 2.LiBr at 60 degrees C led to loss of LiBr and dimerization to generate the orange crystalline compound [mu(N);kappa(P),kappa(C),kappa(N)-{2-(i-Pr(2)PO),6-(CH(2)NBn)-C(6)H(3)}Ni](2), 5. Solid state structural studies show that 1, 3, and 4 are monomeric, square planar complexes involving one Ni-N interaction, whereas complex 5 is a C(2)-symmetric dimer involving four Ni-N interactions and a Ni(2)N(2) core featuring a short Ni-Ni distance (2.51 A). Preliminary reactivity tests have shown that 5 is stable toward weak nucleophiles such as acetonitrile but reacts with strong nucleophiles such as CO or 2,6-Me(2)(C(6)H(3))NC. Reactions with protic reagents showed that phthalimide appears to break the dimer to generate a monomeric species, whereas alcohols appear to leave the dimer intact, giving rise instead to adducts through N...H...O interactions. These ROH adducts of 5 were found to be active precatalysts for the alchoholysis of acrylonitrile with up to 2000 catalytic turnover numbers.

  15. 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.

  16. Technical Writing in the Netherlands.

    ERIC Educational Resources Information Center

    de Vet, Dominique M. W.

    1996-01-01

    Discusses the technical writing profession in the Netherlands. Bases the discussion on two studies--one directed at technical freelancers and another directed at technical writers working within organizations. Gives a profile of technical writers in the Netherlands; an impression of the problems technical writers in organizations deal with;…

  17. 76 FR 64083 - Reliability Technical Conference; Notice of Technical Conference

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-10-17

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF ENERGY Federal Energy Regulatory Commission Reliability Technical Conference; Notice of Technical Conference Take notice that the Federal Energy Regulatory Commission will hold a Technical Conference on Tuesday, November...

  18. 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.

  19. Lewis base-promoted rearrangement of allylic cyanohydrins: construction of functionalized nitriles bearing 1,3-diketone moieties.

    PubMed

    Zhang, Yan-Jing; Hou, Qi-Lan; Wang, Hai-Jing; Liao, Wei-Wei

    2014-11-21

    A novel Lewis base-promoted rearrangement of allylic cyanohydrins has been developed, in which the cyano group was rearranged, directly coupled with the generation of new functional groups. This protocol provides a unique and facile way to prepare highly functionalized nitriles bearing 1,3-diketone moieties under mild reaction conditions. Furthermore, the synthetic transformations of the functionalized products have also been demonstrated.

  20. 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

  1. 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.

  2. 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.

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

    USDA-ARS?s Scientific Manuscript database

    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...

  4. Catalytic amidolysis of amino acid p-nitroanilides using transition state analogue imprinted artificial enzymes: Cooperative effect of pyridine moiety.

    PubMed

    Divya, Mathew; Benny, Thomas; Christy, Philip; Aparna, E P; Devaky, K S

    2017-10-01

    Enzyme-like polymer catalysts with the imprints of phosphonate transition state analogue (TSA) lined along with imidazole and pyridine moieties were synthesized using methacryloyl-l-histidine and 4-vinylpyridine as the functional monomers and phenyl-1-(N-benzyloxycarbonylamino)-2-(phenyl)ethyl phosphonate - the TSA of hydrolytic reaction as the template for the amidolysis of N-benzyloxycarbonyl-l-phenylalanine p-nitroanilide (Z-l-Phe-PNA). Polymers containing different functional groups can act together to provide catalytic activity and selectivity superior to what can be obtained from monofunctional analogues. The higher rate acceleration exhibited by the bifunctional polymer over the monofunctional polymers indicates cooperative catalysis of imidazole and pyridine moieties. The optimum catalytic competence is shown by the bifunctional polymer containing imidazole and pyridine moieties in 2:1M ratio which may be due to alignment of the functional groups in proper H-bond distance. In addition to the non-covalent interactions like hydrogen bonding or π-stacking interactions between the functional groups of the polymer and the template, 3D-microcavities complementary to the geometry of the template are necessary for effective shape selective binding. Michaelis-Menten kinetics implies that only the catalysts with imidazole moieties act as enzyme-like catalysts and imidazole is the key catalytic function of the enzyme mimics. Copyright © 2017 Elsevier Inc. All rights reserved.

  5. 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).

  6. Solvent-free Povarov reaction for synthesizing ferrocenyl quinolines: antioxidant abilities deriving from ferrocene moiety.

    PubMed

    Xi, Gao-Lei; Liu, Zai-Qun

    2014-10-30

    Twenty-two 2-phenyl-4-ferrocenylquinolines are synthesized by Povarov three-component-reaction (3CR) among the substituted anilines, benzaldehydes, and ferrocenylacetylene with Ce(OTf)3 being catalyst in the absence of solvents. The antioxidative effects of the obtained quinolines are estimated by quenching 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonate) cationic radical (ABTS(+·)), 2,2'-diphenyl-1-picrylhydrazyl (DPPH), and galvinoxyl radicals, and by inhibiting Cu(2+)/glutathione (GSH)-, hydroxyl radical (·OH)-, and 2,2'-azobis(2-amidinopropane hydrochloride) (AAPH)-induced oxidations of DNA. It is found that the ferrocenyl group instead of hydroxyl group generates the antioxidative effect for quinoline to quench radicals and to protect DNA against radical-induced oxidations. The antioxidative effect generated by ferrocenyl group can be further increased by the electron-donating moieties such as furan, -N(CH3)2, -OCH3, and ferrocenyl group, while the electron-withdrawing groups such as -NO2 and -Cl are not beneficial for quinolines to be antioxidants. The ferrocenyl group in quinoline exhibits higher antioxidant activity than hydroxyl group in Trolox. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

  7. Synthesis and antitumor activity of new alkylphospholipids containing modifications of the phosphocholine moiety.

    PubMed

    Ukawa, K; Imamiya, E; Yamamoto, H; Mizuno, K; Tasaka, A; Terashita, Z; Okutani, T; Nomura, H; Kasukabe, T; Hozumi, M

    1989-05-01

    New antitumor alkylglycerophospholipids, in which primarily the phosphocholine moiety of the platelet activating factor (PAF) molecule was modified, were synthesized from 1-alkyl-2-substituted glycerols by introducing polar head phosphoryl groups having methylene bridges of various lengths (from 2 to 14 carbons). They were tested for PAF agonistic activity and antitumor properties. In a series of 1-octadecyl-2-acetoacetylglycerophospholipids (1a-f), an increase in the length of the methylene bridge separating the phosphate and trimethylammonio group in the polar head side chain at position 3 of the glycerol backbone resulted in a progressive decrease in PAF agonistic activity and a characteristic change in antitumor activity against human promyelocytic leukemia cells (HL-60). Maximal potency was obtained with the compound having a decamethylene bridge (1e, IC50 value = 1.5 microgram/ml). Thus, alkylphospholipids possessing a decamethylene bridge and a variety of substituents at position 2 (1g-n) were synthesized. They showed potent inhibitory activity with IC50 values ranging from 0.4 to 1.9 micrograms/ml, depending on the nature of the 2-substituent in the phospholipid molecule. In in vivo tests of the present series of alkylglycerophospholipids (1a--n), using mice bearing sarcoma 180 and mice with mammary carcinoma MM46 (both cells and compounds were given i.p.), 1-octadecyl-2-acetoacetyl-3-glyceryl omega-trimethylammoniodecyl phosphate (1e) showed the most potent life-prolonging effect. The structure-activity relationships are discussed.

  8. Asymmetric energy transfer and optical diffraction in novel molecular glass with carbazole moiety

    NASA Astrophysics Data System (ADS)

    Tsutsumi, Naoto; Eguchi, Junya; Sakai, Wataru

    2006-12-01

    Asymmetric energy transfer and optical diffraction under optically interfered beams was presented in composites with novel star-shaped molecular glass end-caped by carbazole moiety, α,α',α″-tris-(4-(carbazoryl)- n-hexyloxyphenyl)-1,3,5-triisopropylbenzene (Tris). Composite consisted of Tris as host matrix, 2,4,7-trinitro-9-fluorenone (TNF) as a sensitizer, ( S)-(-)-1-(4-nitrophenyl)-2-pyrrolidine-methanol (NPP) as a nonlinear optical dye and either tricresyl phosphate (TCP), n-butyl benzyl phthalate (BBP), diphenyl phthalate (DPP), or dicyclohexyl phthalate (DCP) as a plasticizer. Asymmetric two beam coupling (asymmetric energy transfer) and beam diffraction were achieved with no external field. Glass transition temperature of the composites plays an important role for these phenomena of asymmetric energy transfer and optical diffraction with no external field. Highest net gain coefficient of 59.7 cm -1 with optical gain of 151.3 cm -1 and absorption coefficient of 91.6 cm -1 was obtained for Tris/NPP/DPP/TNF (35/20/40/5) composite. TNF anion produced by laser illumination plays a key role of beam diffraction and asymmetric two beam coupling in the composites.

  9. Self-assembled layers based on isomerizable stilbene and diketoarylhydrazone moieties.

    PubMed

    Marten, Jan; Erbe, Andreas; Critchley, Kevin; Bramble, Jonathan P; Weber, Edwin; Evans, Stephen D

    2008-03-18

    The ability to form self-assembled layers on gold (Au) using five organosulfur compounds that contain isomerizable groups has been investigated. The isomerizable groups are either stilbene or diketoarylhydrazone derivatives. To anchor them on a gold surface, the isomerizable groups have been combined with sulfur-containing groups (disulfide, 1,2-dithiolane, and thiophene). The resulting thin films assembled on gold were characterized by X-ray photoelectron spectroscopy (XPS), infrared (FTIR) reflectance spectroscopy, ellipsometry, and water contact angle measurements. Though all substances have the potential to form self-assembled monolayers (SAMs), only two of them, disulfanediyl-bis(ethane-2,1-diyl) bis(4-styrylbenzoate) (1) and 4-[(2,4-dioxo-3-pentylidene)diazane-2,2,1-triyl]phenyl thioctate (4), yield the expected structure, the latter one showing the possibility to incorporate diarylketohydrazone moieties into SAMs. The compound 4-[(2,4-dioxo-3-pentylidene)diazane-2,2,1-triyl]phenyl thiophene-2-carboxylate (5) does not self-assemble on gold, but 4-styrylphenyl thioctate (3) presumably forms multilayers. In the case of disulfanediyl-bis(ethane-2,1-diyl) bis[4-(p-nitrostyryl)benzoate] (2), we propose a structure with a fraction of the molecules bound to gold via the nitro group. The results show that the propensity of organosulfur compounds to self-assemble on gold not only is determined by the sulfur-containing group but also is affected by the complete molecule.

  10. Tails wagging the dogs: On phosphoinositides and their fatty acyl moieties.

    PubMed

    Heilmann, Ingo

    2008-10-01

    Phosphoinositides (PIs) control various cellular functions of eukaryotic cells. PIs are derived from phosphatidylinositol (PtdIns) by phosphorylation of the inositol-ring in the lipid-head group; the action of specific lipid kinases gives rise to a family of structurally-related PIs, in plants representing PtdIns-mono-, and -bisphosphates. Specific PIs, such as phosphatidylinositol4,5-bisphosphate (PtdIns(4,5)P(2)), can influence more than one physiological process, raising the question as to how interactions with alternative protein partners are coordinated. Previous studies have proposed that PIs are organized by spatiotemporal compartmentation into distinct functional pools, however, mechanisms for the generation and maintenance of such pools have not been presented. Several recent studies now indicate that not only the distinctive inositolpolyphosphate head groups may be relevant for PI function but also the associated fatty acyl-moieties, which may be involved in sorting of PI precursors into distinct pools. This mini-review aims at highlighting recent evidence that PI acylgroups exert relevant effects on signaling.

  11. Farnesyl Diphosphate Analogues with Aryl Moieties are Efficient Alternate Substrates for Protein Farnesyltransferase

    PubMed Central

    Subramanian, Thangaiah; Pais, June E.; Liu, Suxia; Troutman, Jerry M.; Suzuki, Yuta; Subramanian, Karunai Leela; Fierke, Carol; Andres, Douglas A.; Spielmann, H. Peter

    2012-01-01

    Farnesylation is an important post-translational modification essential for proper localization and function of many proteins. Transfer of the farnesyl group from farnesyl diphosphate (FPP) to proteins is catalyzed by protein farnesyltransferase (FTase). We employed a library of FPP analogues with a range of aryl groups substituting for individual isoprene moieties to examine some of the structural and electronic properties of analogue transfer to peptide catalyzed by FTase. Analysis of steady-state kinetics for modification of peptide substrates revealed that the multiple turnover activity depends on the analogue structure. Analogues where the first isoprene is replaced by a benzyl group and an analogue where each isoprene is replaced by an aryl group are good substrates. In sharp contrast with the steady-state reaction, the single turnover rate constant for dansyl-GCVLS alkylation was found to be the same for all analogues, despite the increased chemical reactivity of the benzyl analogues and the increased steric bulk of other analogues. However, the single turnover rate constant for alkylation does depend on the Ca1a2X peptide sequence. These results suggest that the isoprenoid transition state conformation is preferred over the inactive E•FPP• Ca1a2X ternary complex conformation. Furthermore, these data suggest that the farnesyl binding site in the exit groove may be significantly more selective for the farnesyl diphosphate substrate than the active site binding pocket and therefore might be a useful site for design of novel inhibitors. PMID:22989235

  12. Synthesis, optical and electrochemical study of bipolar heterocyclic systems, including 1,2,4-oxadiazole moiety

    NASA Astrophysics Data System (ADS)

    Selivanova, D. G.; Mayorova, O. A.; Gorbunov, A. A.; Vasyanin, A. N.; Dmitriev, M. V.; Shklyaeva, E. V.; Abashev, G. G.

    2016-12-01

    Two new 3,5-dihetarylsubstituted 1,2,4- oxadiazoles 8 a,b, including N-alkyl substituted carbazole and thiophene moieties, were synthesized as potential components of materials for organic electronics devices. Optical and electrochemical properties of all new compounds were investigated. On the basis of the experimental UV absorption data, the values of bandgap energies equal to 3.44 eV (8a) and 3.05 eV (8b) were determined. The values of their ionization potentials, HOMO levels (-5.62 eV for 8a, -5.46 eV - for 8b), as well as their electron affinity levels, LUMO levels (-2.2 eV for 8a, -2.4 eV - for 8b), were calculated from the results of electrochemical studies. The energy of the triplet excited states of 8 a,b was defined with the help of time-dependent density functional theory (TD-DFT), comprising 2.68 eV (8a) and 2.32 eV (8b), where the greatest value of this parameter was for the compound with a shorter conjugation chain.

  13. 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

  14. The Biosynthesis of the Thiazole Moiety of Thiamin in the Archaeon Halobacterium salinarum.

    PubMed

    Hayashi, Maria; Kijima, Yukie; Tazuya-Murayama, Keiko; Yamada, Kazuko

    2015-01-01

    The biosynthetic pathways of the thiazole moiety of thiamin were studied in the archaeon Halobacterium salinarum. Thiamin is generated by the union of 4-amino-5-hydroxymethyl-2-methylpyrimidine (pyrimidine) and 5-(2-hydroxyethyl)-4-methylthiazole (thiazole). The biosynthesis of thiazole is different in facultative anaerobes, aerobes and eukaryotes. In eukaryotes, the C-4, -4', -5, -5' and -5" of the thiazole is biosynthesized from nicotinamide adenine dinucleotide (NAD), with cysteine as S donor and the C-2 and N atoms of glycine. In facultative anaerobic bacteria, such as Escherichia coli, the precursors of the thiazole are the N and C-2 atoms from tyrosine and C-4, -4', -5, -5' and -5" from 1-deoxy-D-xylurose-5-phosphate, again with cysteine as S donor. In aerobic bacteria, such as Bacillus subtilis, L-tyrosine is replaced by glycine. In Archaea, known as the third domain of life, the biosynthetic pathway of thiamin has not yet been elucidated. In the present study in the archaeon H. salinarum, it was shown that both the N and C-2 from glycine are incorporated into the thiazole, rather than the N atom coming from L-tyrosine. These results show that thiazole biosynthesis in H. salinarum more closely resembles the biosynthetic pathway found in eukaryotes.

  15. Small flexible structure for targeted delivery of therapeutic and imaging moieties in precision medicine

    PubMed Central

    Li, Bingjie; Qiu, Xiuchun; Zou, Chaoxia; Ran, Henry; Zhang, Fujun; Ke, Shi

    2016-01-01

    The goals of precision medicine are to link diagnostic and therapeutic agents, improve clinical outcomes, and minimize side effects. We present a simple, small, flexible three-armed core structure that can be conjugated to targeting, imaging, and therapeutic moieties. The targeting molecule can be a peptide, protein, or chemical compound. The diagnostic reporter can be optical and/or nuclear in nature, and can be replaced by chemo- and/or radiotherapeutic compounds for treatment using a single targeting molecule. Imaging components can be used to detect disease biomarkers, monitor treatment response, and guide surgery in real-time to create a tumor-free margin. Isotope impurity can be exploited to visualize whole-body distribution of therapeutic agents. The one-to-one ratio of targeting component to therapeutic agents facilitates dose calculation. The simple synthesis and flexible, modular nature of the agent facilitate high-purity, large-scale production. The core capacity to “seek, treat, and see” may advance precision medicine in the future. PMID:27027441

  16. 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.

  17. Interactions of ruthenium complexes containing indoloquinoline moiety with human telomeric G-quadruplex DNA.

    PubMed

    Yu, Hui-juan; Yu, Lin; Hao, Zhi-feng; Zhao, Ying

    2014-04-24

    G-quadruplex structures are attractive targets for the development of anticancer drugs, as their formation in human telomere could impair telomerase activity, thus inducing apoptosis in cancer cells. Vast majority of G-quadruplex binding molecules have been designed and synthesized. Ruthenium complexes have also been reported to induction or stabilization of G-quadruplex structure of human telomeric sequence, whereas most of them generally promote the formation of antiparallel or hybrid-type G-quadruplex structure. Ruthenium complex that selectively promotes the formation of parallel G-quadruplex structure has rarely been reported. We reported here the interaction of two ruthenium complexes [Ru(bpy)2(mitatp)](2+)1 and [Ru(phen)2(mitatp)](2+)2 (bpy=2,2' bipyridine, phen=1,10-phenanthroline, mitatp=5-methoxy-isatino[1,2-b]-1,4,8,9-tetraazatriphenylene) containing indoloquinoline moiety with human telomeric G-quadruplex DNA (Telo22). Complex 1 binds to Telo22 tightly via a stable π-π stacking interaction and efficiently stabilizes the G-quadruplex structure. Circular dichroism (CD) spectra titration results suggest that complex 1 could induce Telo22 to fold into antiparallel G-quadruplex conformation. Complex 2 exhibits moderate G-quadruplex binding and stabilizing ability, while CD titration data reveals that complex 2 could promote the formation of parallel G-quadruplex structure.

  18. Stability assessment of different chelating moieties used for elemental labeling of bio-molecules

    PubMed Central

    Kretschy, Daniela; Koellensperger, Gunda; Hann, Stephan

    2012-01-01

    Integrating elemental labeling in quantitative LC-ICP-MS based bio-analysis requires fundamental experiments concerning the stability of complexes during analysis. In a competitive approach complex stability of the chelating moieties 1,4,7,10-tetraazacyclododecane-N, N′, N′′, N′′′-tetraaceticacid (DOTA), 1,4,7-triazacyclononane-N, N′, N′′-triacetic acid (NOTA) and diethylenetriaminepentaacetic dianhydride (DTPA) in combination with 11 different lanthanides was investigated under typical chromatographic conditions. Measurements were carried out via LC-ICP-QMS using a novel mixed mode separation method. The influence of chromatographic separation, pH and temperature on complex stability constants was assessed regarding further applications of multiplexing in bio-analytical assays. The limit of detection (LOD) for LC-ICP-QMS were 0.03 nM for all investigated Tm complexes (0.15 fmol absolute). Quantification of the complexes was performed via external, flow injection based calibration. For all investigated complexes the stability was significantly decreased by the chromatographic conditions. Moreover, complexation by DOTA revealed two different signals suggesting the presence of a stable intermediate product. Ln3+-DOTA and Ln3+-NOTA complexes provided high stability at 5 °C and 37°C over a time of 12 hours, whereas Ln3+-DTPA complexes showed significant degradation at 37 °C. PMID:21922111

  19. Enzymatic synthesis and RNA interference of nucleosides incorporating stable isotopes into a base moiety.

    PubMed

    Hatano, Akihiko; Shiraishi, Mitsuya; Terado, Nanae; Tanabe, Atsuhiro; Fukuda, Kenji

    2015-10-15

    Thymidine phosphorylase was used to catalyze the conversion of thymidine (or methyluridine) and uracil incorporating stable isotopes to deoxyuridine (or uridine) with the uracil base incorporating the stable isotope. These base-exchange reactions proceeded with high conversion rates (75-96%), and the isolated yields were also good (64-87%). The masses of all synthetic compounds incorporating stable isotopes were identical to the theoretical molecular weights via EIMS. (13)C NMR spectra showed spin-spin coupling between (13)C and (15)N in the synthetic compounds, and the signals were split, further proving incorporation of the isotopes into the compounds. The RNA interference effects of this siRNA with uridine incorporating stable isotopes were also investigated. A 25mer siRNA had a strong knockdown effect on the MARCKS protein. The insertion position and number of uridine moieties incorporating stable isotopes introduced into the siRNA had no influence on the silencing of the target protein. This incorporation of stable isotopes into RNA and DNA has the potential to function as a chemically benign tracer in cells. Copyright © 2015 Elsevier Ltd. All rights reserved.

  20. Synthesis and electroluminescent properties of anthracene derivatives containing electron-withdrawing oxide moieties

    SciTech Connect

    Yoon, Jhin-yeong; Na, Eun Jae; Park, Soo Na; Lee, Seok Jae; Kim, Young Kwan; Yoon, Seung Soo

    2014-10-15

    Highlights: • Blue fluorescent material is important for application in full-color displays. • We have synthesized emitters based on anthracene connected with oxide moieties. • 1C shows a highly efficient blue EL emission due to electron-injection property. - Abstract: A series of new blue-emitting materials: (4-(10-(naphthalen-2-yl)anthracen-9-yl)phenyl)(phenyl)methanone (1); 9-(naphthalen-2-yl)-10-(4-((diphenyl)phosphine oxide)phenyl)anthracene (2); 9-(naphthalen-2-yl)-10-(4-(phenylsulfonyl)phenyl)anthracene (3) were designed and synthesized via Suzuki cross-coupling reaction. Multilayer OLEDs were fabricated in the following sequence: ITO (180 nm)/NPB (50 nm)/blue materials 1–3 (30 nm)/TPBi (15 nm)/Liq (2 nm)/Al (100 nm). All devices showed the efficient blue EL emissions. In particular, the device using 1 as an emitter exhibited efficient blue electroluminescent properties with a maximum luminous, power, external quantum efficiency and CIE coordinates of 0.36 cd/A, 0.90 lm/W, 0.55% at 20 mA/cm{sup 2} and (x = 0.16, y = 0.20) at 10.0 V, respectively.

  1. Synthesis and in vitro antibacterial activity of gemifloxacin derivatives containing a substituted benzyloxime moiety.

    PubMed

    Feng, Lianshun; Lv, Kai; Liu, Mingliang; Wang, Shuo; Zhao, Jing; You, Xuefu; Li, Sujie; Cao, Jue; Guo, Huiyuan

    2012-09-01

    A series of novel gemifloxacin (GMFX) derivatives containing a substituted benzyloxime moiety with remarkable improvement in lipophilicity were synthesized. The target compounds evaluated for their in vitro antibacterial activity against representative strains. Our results reveal that most of the target compounds have considerable potency against all of the tested gram-positive strains including MRSA and MRSE (MIC: <0.008-8 μg/mL), although they are generally less active than the references against the gram-negative strains. In particular, compound 11l (MIC: <0.008-4 μg/mL) was found to be 8-2048 and 2-128 times more potent than levofloxacin (LVFX) and GMFX against the gram-positive strains, respectively. Moreover, against MRSA clinical isolates, 11l (MIC(90): 1 μg/mL) is 8-fold more active than GMFX, and 2-fold more active than GMFX and moxifloxacin against MRSE clinical isolates (MIC(90): 4 μg/mL). Crown Copyright © 2012. Published by Elsevier Masson SAS. All rights reserved.

  2. High temperature polyimide containing anthracene moiety and its structure, interface, and nonvolatile memory behavior.

    PubMed

    Park, Samdae; Kim, Kyungtae; Kim, Dong Min; Kwon, Wonsang; Choi, Junman; Ree, Moonhor

    2011-03-01

    A high temperature polyimide bearing anthracene moieties, poly(3,3'-di(9-anthracenemethoxy)-4,4'-biphenylene hexafluoroisopropylidenediphthalimide) (6F-HAB-AM PI) was synthesized. The polymer exhibits excellent thermal stability up to around 410 °C. This polymer is amorphous but orients preferentially in the plane of nanoscale thin films. In device fabrications of its nanoscale thin films with metal top and bottom electrodes, no diffusion of the metal atoms or ions between the polymer and electrodes was found; however, the aluminum bottom electrode had somewhat undergone oxide layer (about 1.2 nm thick) formation at the surface during the post polymer layer formation process, which was confirmed to have no significant influence on the device performance. The polymer thin film exhibited excellent unipolar and bipolar switching behaviors over a very small voltage range, less than ±2 V. Further, the PI films show repeatable writing, reading, and erasing ability with long reliability and high ON/OFF current ratio (up to 10(7)) in air ambient conditions as well as even at temperatures up to 200 °C.

  3. 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.

  4. Effect of oligoethylene glycol moieties in porous silicon surface functionalisation on protein adsorption and cell attachment

    NASA Astrophysics Data System (ADS)

    Sweetman, Martin J.; Harding, Frances J.; Graney, Sean D.; Voelcker, Nicolas H.

    2011-05-01

    We report on the synthesis of two carboxy-functional alkene compounds as modifiers of porous silicon (pSi) surface chemistry by means of thermal hydrosilylation. Both alkene compounds have hydrophobic, aliphatic carbon segments, with terminal carboxylic acid functionality appended through a thioether linkage. In one of the alkene linkers, we incorporated a short oligoethylene glycol (OEG) moiety to explore its low-fouling properties when attached to porous silicon. We examined surface stability of the surface-modified porous silicon in aqueous milieu. Albumin and fibronectin were adsorbed and, using carbodiimide chemistry, covalently immobilised to linker-modified porous silicon, and the propensity for mammalian cells to attach to these surfaces investigated. Surface chemistry was characterised by infrared spectroscopy and the stability of porous silicon in an aqueous milieu was investigated by interferometric reflectance spectroscopy (IRS). Surfaces functionalised with the alkene linker containing OEG displayed greater resistance to the adsorption of albumin. This linker also facilitated higher levels of covalent protein immobilisation to the functionalised pSi surface. Higher levels of cell attachment were observed on pSi surfaces with fibronectin covalently immobilised onto the OEG linker, than for fibronectin covalently immobilised on the non-OEG linker.

  5. Synthesis, biological activity and molecular modeling study of new Schiff bases incorporated with indole moiety.

    PubMed

    Halawa, Ahmed H; El-Gilil, Shimaa Mohamed Abd; Bedair, Ahmed H; Shaaban, Mohamed; Frese, Marcel; Sewald, Norbert; Eliwa, Essam M; El-Agrody, Ahmed M

    2017-05-18

    A new series of heterocyclic Schiff bases 2-9 containing indole moiety were synthesized by facile and efficient condensation of indole-3/2/5-carboxaldehyde (1a/1b/1c) with different aromatic and heterocyclic primary amines using conventional and/or microwave irradiation methods. The structures of the obtained compounds were assigned by sophisticated spectroscopic and spectrometric techniques (1D-NMR, 2D-NMR and MS). The synthesized compounds were screened for their cytotoxicity and antibacterial activities. In vitro cytotoxicity screening revealed that compound 5 exhibited moderate activity against KB-3-1 cell line (IC50=57.7 μM) while 5-indolylimino derivative 7 indicated close to the activity (IC50=19.6 μM) in comparison with the positive control (+)-Griseofulvin (IC50=19.2 μM), while the tested compounds 5, 6b, 7 and 9 revealed good or moderate antibacterial activity. In addition, molecular docking study of Schiff bases 2-9 was performed by Molecular Operating Environment (MOE 2014.09) program on the matrix metalloproteinase-8 (MMP-8) (Protein Data Bank (PDB) ID: 1MNC) in an attempt to explore their mode of action as anticancer drugs.

  6. Blue fluorescent materials based on bis(10-phenylanthracen-9-yl) derivatives containing heterocyclic moiety

    NASA Astrophysics Data System (ADS)

    Kim, Young Seok; Yoon, Jhin-yeong; Lee, Hyun Woo; Kim, Jwajin; Lee, Ho Won; Lee, Song Eun; Kim, Young Kwan; Yoon, Seung Soo

    2015-08-01

    We synthesized a series of bis(10-phenylanthracen-9-yl) derivatives containing various heterocyclic moieties such as 9-ethylcarbazole, dibenzofuran and dibenzothiophene (1-3) by Suzuki cross-coupling reactions. To explore electroluminescent properties of these materials, multilayered devices were fabricated with configuration of indium-tin-oxide (ITO) (180 nm)/4,4‧-bis(N-(1-naphthyl)-N-phenylamino)biphenyl (NPB) (50 nm)/Emitters 1-3 (30 nm)/Tris(8-hydroxyquinolinato) aluminium (Alq3) (15 nm)/lithium quinolate (Liq) (2.0 nm)/Al (100 nm). In particular, a device using 2,8-bis(10-phenylanthracen-9-yl)dibenzo[b,d]furan (2), as an emitter, exhibited efficient blue emission with maximum luminance, luminous, power and external quantum efficiency of 620 cd/m2, 2.05 cd/A, 1.05 lm/W, 1.43% at 20 mA/cm2, and CIE coordinates of (x = 0.18, y = 0.17) at 8 V, respectively.

  7. Synthesis and antibacterial activities of novel pleuromutilin derivatives with a substituted pyrimidine moiety.

    PubMed

    Yi, Yunpeng; Xu, Ximing; Liu, Yu; Xu, Shuijin; Huang, Xin; Liang, Jianping; Shang, Ruofeng

    2017-01-27

    The alarming growth of multidrug-resistant bacteria such as methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant Enterococci (VRE) has become a major global health hazard. Therefore, urgent demand for new antibiotics with a unique mechanism of action is very necessary. The present study reports the design, synthesis, and antibacterial studies of a series of novel pleuromutilin derivatives with substituted 6-amino pyrimidine moieties. Most of the tested compounds exhibited highly potent anti-MRSA or Staphylococcus aureus (S. aureus) activities. 14-O-[(4,6-Diamino -pyrimidine-2-yl) thioacetyl] mutilin (3) and 14-O-[(2-((3R)-3-Hydroxymethylpiperidine-1-yl)-acetamido-6-aminopyrimidine-2-yl) thioacetyl] mutilin (5h) were the most active compounds and showed higher antibacterial activities. Compound 3 displayed rapid bactericidal activity and affected bacterial growth with the same manner as tiamulin fumarate. Docking experiments for compounds 3 and 5h carried out on the peptidyl transferase center (PTC) of 23S rRNA provided the information about the binding model. In vivo mouse systemic infection experimental results confirmed the therapeutic efficacy of compound 3, with ED50 of 4.22 mg/kg body weight against MRSA. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  8. A role of glycosyl moieties in the stabilization of bitter gourd (Momordica charantia) peroxidase.

    PubMed

    Fatima, Aiman; Husain, Qayyum

    2007-06-01

    The possible role of carbohydrate moieties in the stabilization of proteins has been investigated by using bitter gourd peroxidase as a model system. A comparative study of glycosylated and non-glycosylated isoenzymes of bitter gourd peroxidase was performed at various temperatures, pH, water-miscible organic solvents, detergents and chaotropic agent like urea. The pH-optima and temperature-optima of both glycosylated and non-glycosylated isoforms of bitter gourd peroxidase remained unchanged. The probes employed were changes in the enzyme activity and fluorescence. The glycosylated form of peroxidase retained greater fraction of enzyme activity against the exposure caused by various physical and chemical denaturants. The unfolding of both forms of enzyme in the presence of high urea concentrations, studied by fluorescence, indicated greater perturbations in the conformation of non-glycosylated preparation. The different properties examined thus indicated that glycosylation plays an important role in the stabilization of native conformation of proteins against the inactivation caused by various types of denaturants.

  9. Design, Synthesis, and Acaricidal/Insecticidal Activities of Oxazoline Derivatives Containing a Sulfur Ether Moiety.

    PubMed

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

    2015-11-11

    On the basis of etoxazole, a series of novel 2-(2,6-difluorophenyl)-4-(4-substituted phenyl)-1,3-oxazolines containing a sulfur ether moiety were designed and synthesized via the key intermediate N-(1-(4-(bromomethyl)phenyl)-2-chloroethyl)-2,6-difluorobenzamide. The bioassay results showed that most of these designed target compounds exhibited excellent acaricidal activity against both the eggs and larvae of Tetranychus cinnabarinus, especially the eggs. Among compounds with high activity against the eggs of mites, the LC50 values of 2, 11, 17, and 19 were 0.0003, 0.0002, 0.0005, and 0.0008 mg L(-1), respectively, much lower than that of etoxazole (0.0089 mg L(-1)). Compound 2 was chosen to evaluate the acaricidal activity in the field, and the results displayed that at a concentration of 22 mg kg(-1), 2 had a much better control effect than etoxazole against both T. cinnabarinus and P. latus on eggplant. Some compounds also showed good insecticidal activities against oriental armyworm and mosquito. On the basis of our research, the newly found structure-activity relationship may guide the development of new acaricides/pesticides that are required in the agriculture market.

  10. Design, Synthesis, Acaricidal Activity, and Mechanism of Oxazoline Derivatives Containing an Oxime Ether Moiety.

    PubMed

    Li, Yongqiang; Li, Chaojie; Zheng, Yanlong; Wei, Xingcun; Ma, Qiaoqiao; Wei, Peng; Liu, Yuxiu; Qin, Yaoguo; Yang, Na; Sun, Yufeng; Ling, Yun; Yang, Xinling; Wang, Qingmin

    2014-03-27

    Two series of novel 2,4-diphenyl-1,3-oxazolines containing an oxime ether moiety were designed and synthesized via the key intermediate N-(2-chloro-1-(p-tolyl)ethyl)-2,6-difluorobenzamide. The bioassay results showed that the target compounds with an oxime ether substituent at the para position of 4-phenyl exhibited excellent acaricidal activity against Tetranychus cinnabarinus in the laboratory. Moreover, all of the target compounds had much higher activities than etoxazole, as the ovicidal and larvicidal activities of the target compounds I-a-I-l and II-a-II-n against T. cinnabarinus were all over 90% at 0.001 mg L(-1), but etoxazole gave only 30% and 40% respectively at the same concentration. The activity order of compounds with regard to acaricidal activity in vivo was almost consistent with their affinity activity with sulfonylurea receptor (SUR) of Blattella germanica in vitro, hence, it was supposed that the acaricidal mechanism of action of the target compounds was that they can bind with the site of SUR and therefore inhibit chitin synthesis. Moreover, the eminent effect of the compound II-l, [2-(trifluoromethyl)benzaldehyde O-(4-(2-(2,6-difluorophenyl)-4,5-dihydrooxazol-4-yl)benzyl) oxime], against Panonychus citri and T. cinnabarinus in the field indicated that II-l exhibited a promising application prospect as a new candicate for controlling spider mites in the field.

  11. Synthesis and biological evaluation of novel indole-pyrimidine hybrids bearing morpholine and thiomorpholine moieties.

    PubMed

    Diao, Peng-Cheng; Li, Qiu; Hu, Meng-Jin; Ma, Yu-Feng; You, Wen-Wei; Hong, Kwon Ho; Zhao, Pei-Liang

    2017-07-07

    Based on our previous screening hit compound 1, a series of novel indole-pyrimidine hybrids possessing morpholine or thiomorpholine moiety were synthesized via an efficient one-pot multistep synthetic method. The antiproliferative activities of the synthesized compounds were evaluated in vitro against four cancer cell lines including HeLa, MDA-MB-231, MCF-7, and HCT116. The results revealed that most compounds possessed moderate to excellent potency. The IC50 values of the most promising compound 15 are 0.29, 4.04, and 9.48 μM against MCF-7, HeLa, and HCT116 cell lines, respectively, which are 48.0, 4.9, and 1.8 folds more active than the lead compound 1. Moreover, fluorescence-activated cell sorting analysis revealed that compound 14 showing the highest activity against HeLa (IC50 = 2.51 μM) displayed a significant effect on G2/M cell-cycle arrest in a concentration-dependent manner in HeLa cell line. In addition, representative nine active hybrids were evaluated for tubulin polymerization inhibitory activities, and compound 15 exhibited the most potent anti-tubulin activity showing 42% inhibition at 10 μM. These preliminary results encourage a further investigation on indole-pyrimidine hybrids for the development of potent anticancer agents that inhibit tubulin polymerization. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  12. 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

  13. In vitro labeling of the sialic acid moiety of glycoconjugates with carbon-14

    SciTech Connect

    Carubelli, R.; Wen, G.; McCaffree, D.R.

    1984-03-01

    Labeling of sialoglycoproteins with carbon-14 in vitro was performed by reacting the aldehyde groups, generated by mild periodate oxidation of the terminal sialyl groups, with /sup 14/C-labeled sodium cyanide to produce the labeled cyanohydrin derivatives (Kiliani reaction). Labeling with tritium was carried out by reduction by the aldehyde groups generated on the sialyl residues with /sup 3/H-labeled sodium borohydride following standard procedures. The behavior of both types of labeled specimens of fetuin and ovine submaxillary mucin, individually and in mixtures, was investigated by gel-filtration chromatography, gel electrophoresis, and cesium bromide gradient ultracentrifugation. The labeled sialyl residues were subjected to partial characterization; color yield with the resorcinol and thiobarbituric acid reagents, behavior on ion-exchange chromatography, and susceptibility to mild acid and enzymatic hydrolyses. In addition to these model glycoproteins, this procedure was also utilized to label the sialoglycoproteins present in human tracheobronchial secretions collected from normal subjects and patients with chronic bronchitis. The potential uses of this approach for comparative studies of normal and pathological sialoglycoconjugates available in minute amounts is described. The extension of this approach to the labeling of the galactosyl and N-acetylgalactosaminyl moieties of glycoconjugates following treatment with galactose oxidase is outlined. 21 references.

  14. Experimental and Theoretical Evaluation of the Ethynyl Moiety as a Halogen Bioisostere

    PubMed Central

    2015-01-01

    Bioisosteric replacements are widely used in medicinal chemistry to improve physicochemical and ADME properties of molecules while retaining or improving affinity. Here, using the p53 cancer mutant Y220C as a test case, we investigate both computationally and experimentally whether an ethynyl moiety is a suitable bioisostere to replace iodine in ligands that form halogen bonds with the protein backbone. This bioisosteric transformation is synthetically feasible via Sonogashira cross-coupling. In our test case of a particularly strong halogen bond, replacement of the iodine with an ethynyl group resulted in a 13-fold affinity loss. High-resolution crystal structures of the two analogues in complex with the p53-Y220C mutant enabled us to correlate the different affinities with particular features of the binding site and subtle changes in ligand binding mode. In addition, using QM calculations and analyzing the PDB, we provide general guidelines for identifying cases where such a transformation is likely to improve ligand recognition. PMID:26378745

  15. 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.

  16. Modified hydrolysis kinetics of the active lactone moiety of 10-hydroxycamptothecin by liposomal encapsulation.

    PubMed

    Shi, Kai; Tian, Ye; Jiang, Yanbo; Wang, Lan; Cui, Fude

    2010-12-01

    The key structural requirement for the antitumor activity of 10-hydroxycamptothecin (HCPT) is the intact lactone moiety which is always instability and suffered from pH-dependent hydrolysis. The aim of this study was to evaluate the protection effects of liposomal encapsulation on the labile lactone ring. Mono-modal dispersed quasi-spherical liposomes with mean diameter of 145 nm and high drug entrapment efficiency of 90% were obtained under optimal conditions. The in vitro hydrolysis kinetics behaviors of lactone were studied in varied pH buffers. Compared to that of free HCPT in solution formulation, both the hydrolysis half-life and observed equilibrium constant of liposomal HCPT were increased significantly along with the decreased apparent hydrolysis rate constant. The plasma pharmacokinetics was studied by assessing the lactone stability versus time profiles in vivo following intravenous administration of free and liposomal HCPT. The liposomal encapsulation led to a twofold increase in the AUC values and significant decrease in the plasma clearance of lactone (P < 0.05). There was a good correlation between in vitro and in vivo stability of HCPT-lactone. These results suggested a potential application of the novel liposome formulation for the stable delivery system of HCPT.

  17. Biosynthesis of the thiazole moiety of thiamin pyrophosphate (vitamin B1).

    PubMed

    Park, Joo-Heon; Dorrestein, Pieter C; Zhai, Huili; Kinsland, Cynthia; McLafferty, Fred W; Begley, Tadhg P

    2003-10-28

    While most of the proteins required for the biosynthesis of thiamin pyrophosphate have been known for more than a decade, the reconstitution of this biosynthesis in a defined biochemical system has been difficult due to the novelty of the chemistry involved. Here we demonstrate the first successful enzymatic synthesis of the thiazole moiety of thiamin from glycine, cysteine, and deoxy-D-xylulose-5-phosphate using overexpressed Bacillus subtilis ThiF, ThiS, ThiO, ThiG, and a NifS-like protein. This has facilitated the identification of the biochemical function of each of the proteins involved: ThiF catalyzes the adenylation of ThiS; NifS catalyzes the transfer of sulfur from cysteine to the acyl adenylate of ThiS; ThiO catalyzes the oxidation of glycine to the corresponding imine; and ThiG catalyzes the formation of the thiazole phosphate ring. The complex oxidative cyclization reaction involved in the biosynthesis of the thiamin thiazole has been greatly simplified by replacing ThiF, ThiS, ThiO, and NifS with defined biosynthetic intermediates in a reaction where ThiG is the only required enzyme.

  18. Synthesis, Aggregation Induced Emission and Mechanochromic Luminescence of New β-Diketone Derivatives Bearing Tetraphenylene Moieties.

    PubMed

    Shi, Haijie; Liu, Rui; Zhu, Senqiang; Gong, Qiqi; Shi, Hong; Zhu, Xiaolin; Zhu, Hongjun

    2016-11-01

    A series of β-diketone derivatives bearing tetraphenylene (TPE) moieties were synthesized and characterized. Their photophysical properties were investigated systematically via spectroscopic and theoretical methods. All compounds exhibit broad absorption bands between 300 and 450 nm, which are assigned to the (1)π-π* transition of the conjugated system mixed intramolecular charge-transfer (ICT) transitions. Meanwhile, the emission of these compounds in solution at room temperature (λ em = 458 ~ 509 nm) can be attributed to the (1)π,π*/(1)ICT state. Introduction of freely rotatable TPE to conventional β-diketone luminophors quenches their light emissions in the solutions, but endows these molecules with aggregation-induced emission (AIE) characteristics in the condensed phase due to the restriction of intramolecular rotation. The spectroscopic studies and theoretical calculations indicate that the photophysical properties of these β-diketone derivatives can be tuned by the appended substituents, which would be useful for rational design of AIE compounds with high solid state luminescence performance. Furthermore, these AIE-active compounds exhibited distinct piezofluorochromic properties and switched reversibly upon grinding-fuming. Their photophysical properties have been investigated with the aim to provide a basis for elucidating the structure-property correlations and developing new multi-stimuli responsive luminescent materials.

  19. 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.

  20. Hydrogen Peroxide Generation and Biocompatibility of Hydrogel-Bound Mussel Adhesive Moiety

    PubMed Central

    Meng, Hao; Li, Yuting; Faust, Madeline; Konst, Shari; Lee, Bruce P.

    2015-01-01

    To decouple the extracellular oxidative toxicity of catechol adhesive moiety from its intracellular non-oxidative toxicity, dopamine was chemically bound to a non-degradable polyacrylamide hydrogel through photo-initiated polymerization of dopamine methacrylamide (DMA) with acrylamide monomers. Network-bound dopamine released cytotoxic levels of H2O2 when its catechol side chain oxidized to quinone. Introduction of catalase at a concentration as low as 7.5 U/mL counteracted the cytotoxic effect of H2O2 and enhanced the viability and proliferation rate of fibroblasts. These results indicated that H2O2 generation is one of the main contributors to the cytotoxicity of dopamine in culture. Additionally, catalase is a potentially useful supplement to suppress the elevated oxidative stress found in typical culture conditions and can more accurately evaluate the biocompatibility of mussel-mimetic biomaterials. The release of H2O2 also induced a higher foreign body reaction to catechol-modified hydrogel when it was implanted subcutaneously in rat. Given that H2O2 has a multitude of biological effects, both beneficiary and deleterious, regulation of H2O2 production from catechol-containing biomaterials is necessary to optimize the performance of these materials for a desired application. PMID:25676582

  1. [Synthesis of novel beta-aminoalcohols containing nabumetone moiety with potential antidiabetic activity].

    PubMed

    Zhang, Kun; Yan, Ju-fang; Tang, Xue-mei; Liu, Hong-ping; Fan, Li; Zhou, Guang-ming; Yang, Da-cheng

    2011-04-01

    Twenty five new beta-aminoalcohols containing nabumetone moiety were prepared via the reduction of potassium borohydride with a convenient and efficient procedure, starting from beta-aminoketones that have been synthesized by our group. Their chemical structures were determined by IR, MS, 1H NMR, 13C NMR, HR-MS and antidiabetic activities were screened in vitro. Preliminary results revealed that the antidiabetic activity of most beta-aminoalcohols were better than that of the corresponding beta-aminoketones. Although most compounds showed weak antidiabetic activity, the alpha-glucosidase inhibitory activity of compounds 5hd(1) and 5id(2) reached 74.37% and 90.15%, respectively, which were superior to the positive control. The relative peroxisome proliferator-activated receptor response element (PPRE) activity of five compounds were more than 60%, among them compound 5ca possessed the highest activity (112.59%). As lead molecules of antidiabetic agents, compounds 5hd(1), 5id(2) and 5ca deserve further study.

  2. Synthesis and antidiabetic performance of β-amino ketone containing nabumetone moiety.

    PubMed

    Wang, Hang; Yan, Ju-fang; Song, Xiao-li; Fan, Li; Xu, Jin; Zhou, Guang-ming; Jiang, Li; Yang, Da-cheng

    2012-03-15

    We wish to report the further design and improved synthesis that resulted in two series of target molecules, TM-1 and TM-2, with remarkably simplified structures containing β-amino ketone of discrete nabumetone moiety. These were obtained via a 'one-pot, two-step, three-component' protocol of Mannich reaction with yield up to 97%. A total of 28 out of 31 new compounds were characterized using (1)H NMR, (13)C NMR, ESI MS and HRMS techniques. Studies on their antidiabetic activities, screened in vitro at 10 μg mL(-1) level, indicate that TM-2 possesses peroxisome proliferator-activated receptor activation and α-glucosidase inhibition activity significantly stronger than that of TM-1, and also that of the series B compounds that were previously synthesized by the group. Analysis of the structure-activity relationship points to the sulfanilamide unit as the most probable potent group of β-amino ketone and, on the basis of which, a tangible strategy is presented for the development of new antidiabetic drugs.

  3. Oxidation of antibacterial molecules by aqueous ozone: moiety-specific reaction kinetics and application to ozone-based wastewater treatment.

    PubMed

    Dodd, Michael C; Buffle, Marc-Olivier; Von Gunten, Urs

    2006-03-15

    Ozone and hydroxyl radical (*OH) reaction kinetics were measured for 14 antibacterial compounds from nine structural families, to determine whether municipal wastewater ozonation is likely to result in selective oxidation of these compounds' biochemically essential moieties. Each substrate is oxidized by ozone with an apparent second-order rate constant, k''(O3,app) > 1 x 10(3) M(-1) s(-1), at pH 7, with the exception of N(4)-acetylsulfamethoxazole (K''(O3,app) is 2.5 x 102 M(-1) s(-1)). k''(O3,app) values (pH 7) for macrolides, sulfamethoxazole, trimethoprim, tetracycline, vancomycin, and amikacin appear to correspond directly to oxidation of biochemically essential moieties. Initial reactions of ozone with N(4)-acetylsulfamethoxazole, fluoroquinolones, lincomycin, and beta-lactams do not lead to appreciable oxidation of biochemically essential moieties. However, ozone oxidizes these moieties within fluoroquinolones and lincomycin via slower reactions. Measured k''(O3,app) values and second-order *OH rate constants, k''(*OH,app) were utilized to characterize pollutant losses during ozonation of secondary municipal wastewater effluent. These losses were dependent on k''(O3,app), but independent of k''(*OH,app). Ozone doses > or =3 mg/L yielded > or =99% depletion of fast-reacting substrates (K''(O3,app) > 5 x 10(4) M(-1) s(-1)) at pH 7.7. Ten substrates reacted predominantly with ozone; only four were oxidized predominantly by .OH. These results indicate that many antibacterial compounds will be oxidized in wastewater via moiety-specific reactions with ozone.

  4. Interaction between total body gamma-irradiation and choline deficiency triggers immediate modulation of choline and choline-containing moieties.

    PubMed

    Batra, Vipen; Kislay, Binita; Devasagayam, Thomas Paul Asir

    2011-12-01

    The objective of this study was to examine the effect of 60Co-gamma (γ) radiation on acute phase modulation, if any, of choline and choline-containing moieties in choline-deficient subjects. Corresponding results could provide information that might be useful in the management of adverse effects of γ-radiation. Male Swiss mice maintained on a choline-sufficient diet (CSD) and choline-free diet (CFD) based on AIN-93M formula, were subjected to whole body γ-irradiation (2-6 Gy). Liver, serum and brain samples from each group were then tested for: (i) Alterations in choline and choline-containing moieties such as phosphatidylcholine (PC) and sphingomyeline (SM); and (ii) modulation of choline profile modulating enzymes such as phospholipase D (PLD) and total sphingomyelinase (t-SMase). Liver and brain samples were also subjected to histo-pathological examinations. No significant changes were observed in folate, choline, choline-containing moieties and choline-modulating enzymes in choline-sufficient mice. In contrast, interaction between cytotoxic effects of γ-radiation and choline deficiency modulated choline and choline-containing moieties. Feeding CFD reduced hepatic concentrations of choline, PC and SM whereas PLD and t-SMase activities were significantly raised. The decrease in liver choline and choline-containing moieties was accompanied by an increase in blood choline concentration. Despite choline deficiency, the level of choline and acetylcholine synthesizing enzyme choline acetyltransfease (ChAT) significantly increased in the brain. We propose that choline deprivation and γ-radiation interact to modulate choline reserves of hepatic tissue, which might release choline to blood. Our studies also clearly showed that interaction between choline deficiency and γ-radiation might substantially enhance liver adipogenesis.

  5. RASSP Final Technical Report.

    DTIC Science & Technology

    1992-10-21

    AD-A258 56211t Ul!Il Hili11111 IMIl Uli GE Aerospace Advanced Technology Laboratories RASSP Final Technical Report DTIC CLIN 0002AB S /= 2 C U...2. REPORT DATE 4 REPORT TYPE AND DATES COVERED October 21, 1992 - Technical Report 5/18/92 - 10/21/92 4. TITLE AND SUBTITLE 5. FUNDING NUMBERS Rapid...Prototyping of Application Specific Signal CMDA972-92-R-O017 Processors (RASSP) Program - Stuay Phase Final Technical Report 6. AUTHOR(S) John 6delsh

  6. Depleted Uranium: Technical Brief

    EPA Pesticide Factsheets

    This technical brief provides accepted data and references to additional sources for radiological and chemical characteristics, health risks and references for both the monitoring and measurement, and applicable treatment techniques for depleted uranium.

  7. OSH technical reference manual

    SciTech Connect

    Not Available

    1993-11-01

    In an evaluation of the Department of Energy (DOE) Occupational Safety and Health programs for government-owned contractor-operated (GOCO) activities, the Department of Labor`s Occupational Safety and Health Administration (OSHA) recommended a technical information exchange program. The intent was to share written safety and health programs, plans, training manuals, and materials within the entire DOE community. The OSH Technical Reference (OTR) helps support the secretary`s response to the OSHA finding by providing a one-stop resource and referral for technical information that relates to safe operations and practice. It also serves as a technical information exchange tool to reference DOE-wide materials pertinent to specific safety topics and, with some modification, as a training aid. The OTR bridges the gap between general safety documents and very specific requirements documents. It is tailored to the DOE community and incorporates DOE field experience.

  8. SAM Technical Contacts

    EPA Pesticide Factsheets

    These technical contacts are available to help with questions regarding method deviations, modifications, sample problems or interferences, quality control requirements, the use of alternative methods, or the need to address analytes or sample types.

  9. Performance Technical Report

    DTIC Science & Technology

    1991-07-08

    II AD-A238 575 Performance Technical Report DTIC A - W...CTE JUL18 1991 Under ONR Grant D N00014-90-J-1526 P’ ’: A-fl :’ C ’e~roduct. by-’ ll bv I...1991 Performance Technical Report ONR Grant Number NOOO14-90-J-1526 Distribution Scientific Offire Code: 1122MM 3 copies Robert Abbey Office of Naval

  10. 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. Copyright © 2016 Elsevier Ltd. All rights reserved.

  11. Reduction of CO2 using a Rhenium Bipyridine Complex Containing Ancillary BODIPY Moieties

    PubMed Central

    Teesdale, Justin J.; Pistner, Allen J.; Yap, Glenn P.A.; Ma, Ying-Zhong; Lutterman, Daniel A.; Rosenthal, Joel

    2014-01-01

    The reduction of carbon dioxide to chemical fuels such as carbon monoxide is an important challenge in the field of renewable energy conversion. Given the thermodynamic stability of carbon dioxide, it is difficult to efficiently activate this substrate in a selective fashion and the development of new electrocatalysts for CO2 reduction is of prime importance. To this end, we have prepared and studied a new fac-ReI(CO)3 complex supported by a bipyridine ligand containing ancillary BODIPY moieties ([Re(BB2)(CO)3Cl]). Voltammetry experiments revealed that this system displays a rich redox chemistry under N2, as [Re(BB2)(CO)3Cl] can be reduced by up to four electrons at modest potentials. These redox events have been characterized as the ReI/0 couple, and three ligand based reductions – two of which are localized on the BODIPY units. The ability of the BB2 ligand to serve as a non-innocent redox reservoir is manifest in an enhanced electrocatalysis with CO2 as compared to an unsubstituted Re-bipyridine complex lacking BODIPY units ([Re(bpy)(CO)3Cl]). The second order rate constant for reduction of CO2 by [Re(BB2)(CO)3Cl] was measured to be k = 3400 M−1s−1 at an applied potential of −2.0 V versus SCE, which is roughly three times greater than the corresponding unsubstituted Re-bipyridine homologue. Photophysical and photochemical studies were also carried out to determine if [Re(BB2)(CO)3Cl] was a competent platform for CO2 reduction using visible light. These experiments showed that this complex supports unusual excited state dynamics that precludes efficient CO2 reduction and are distinct from those that are typically observed for fac-ReI(CO)3 complexes. PMID:25395735

  12. Influence of carbohydrate moieties on the immunogenicity of human immunodeficiency virus type 1 recombinant gp160.

    PubMed Central

    Benjouad, A; Gluckman, J C; Rochat, H; Montagnier, L; Bahraoui, E

    1992-01-01

    The role of carbohydrates in the immunogenicity of human immunodeficiency virus type 1 (HIV-1) glycoproteins (gp160 and gp120) remains poorly understood. We have analyzed the specificity and neutralizing capacity of antibodies raised against native gp160 or against gp160 deglycosylated by either endo F-N glycanase, neuraminidase, or alpha-mannosidase. Rabbits immunized with these immunogens produced antibodies that recognized recombinant gp160 (rgp160) from HIV-1 in a radioimmunoassay and in an enzyme-linked immunosorbent assay. Antibodies elicited by the different forms of deglycosylated gp160 were analyzed for their reactivity against a panel of synthetic peptides. Compared with anti-native gp160 antisera, serum reactivity to most peptides remained unchanged, or it could increase (peptide P41) or decrease. Only antibodies raised against mannosidase-treated gp160 failed to react with a synthetic peptide (peptide P29) within the V3 loop of gp120. Rabbits immunized with desialylated rgp160 generated antibodies which recognized not only rgp160 from HIV-1 but also rgp140 from HIV-2 at high titers. Although all antisera produced against glycosylated or deglycosylated rgp160 could prevent HIV-1 binding to CD4-positive cells in vitro, only antibodies raised against native or desialylated gp160 neutralized HIV-1 infectivity and inhibited syncytium formation between HIV-1-infected cells and noninfected CD4-positive cells, whereas antibodies raised against alpha-mannosidase-treated gp160 inhibited neither virus replication nor syncytium formation. These findings indicate that the carbohydrate moieties of gp160 can modulate the specificity and the protective efficiency of the antibody response to the molecule. Images PMID:1347797

  13. Covalent attachment of heme to the protein moiety in an insect E75 nitric oxide sensor

    PubMed Central

    Aicart-Ramos, Clara; Valhondo-Falcón, Margarita; Ortiz de Montellano, Paul R.; Rodriguez-Crespo, Ignacio

    2012-01-01

    We have recombinantly expressed and purified the ligand binding domains (LBDs) of four insect nuclear receptors of the E75 family. The Drosophila melanogaster and Bombyx mori nuclear receptors were purified as ferric hemoproteins with Soret maxima at 424 nm, whereas their ferrous form had a Soret maximum at 425 nm that responds to ·NO and CO binding. In contrast, the purified LBD of Oncopeltus fasciatus displayed a Soret maximum at 415 nm for the ferric protein that shifted to 425 nm in its ferrous state. Binding of ·NO to the heme moiety of D. melanogaster and B. mori E75 LBD resulted in the appearance of a peak at 385 nm, whereas this peak appeared at 416 nm in the case of the O. fasciatus hemoprotein, resembling the behaviour displayed by its human homolog Rev-erbβ. HPLC analysis revealed that, unlike the D. melanogaster and B. mori counterparts, the heme group of O. fasciatus is covalently attached to the protein through the side-chains of two amino acids. The large sequence homology with O. fasciatus E75 led us to clone and express the LBD of Blattella germanica, which established that its spectral properties closely resemble those of O. fasciatus and that it also has the heme group covalently bound to the protein. Hence, ·NO/CO regulation of the transcriptional activity of these nuclear receptors might be differently controlled among various insect species. In addition, covalent heme binding provides strong evidence that at least some of these nuclear receptors function as diatomic gas sensors rather than heme sensors. Finally, our findings expand the classes of hemoproteins in which the heme group is normally covalently attached to the polypeptide chain. PMID:22946928

  14. Nickel(ii) radical complexes of thiosemicarbazone ligands appended by salicylidene, aminophenol and aminothiophenol moieties.

    PubMed

    Kochem, Amélie; Gellon, Gisèle; Jarjayes, Olivier; Philouze, Christian; du Moulinet d'Hardemare, Amaury; van Gastel, Maurice; Thomas, Fabrice

    2015-07-28

    The nickel(ii) complexes of three unsymmetrical thiosemicarbazone-based ligands featuring a sterically hindered salicylidene (1), aminophenol (2) or thiophenol (3) moiety were synthesized and structurally characterized. The metal ion lies in an almost square planar geometry in all the complexes. The cyclic voltammetry (CV) curve of 1 shows an irreversible oxidation wave at E = 0.49 V, which is assigned to the phenoxyl/phenolate redox couple. The CV curves of 2 and 3 display a reversible one-electron oxidation wave (E1/2 = 0.26 and 0.22 V vs. Fc(+)/Fc, respectively) and an one-electron reduction wave (E1/2 = -1.55 and -1.46 V, respectively). The cations 2(+) and 3(+) as well as the anions 2(-) and 3(-) were generated. The EPR spectra of the cations in THF show a rhombic signal at g1 = 2.034, g2 = 2.010 and g3 = 1.992 (2(+)) and g1 = 2.069, g2 = 2.018, g3 = 1.986 (3(+)) that is consistent with a main radical character of the complexes. The difference in anisotropy is assigned to the different nature of the radical, iminosemiquinonate vs. iminothiosemiquinonate. The anions display an isotropic EPR signal at giso = 2.003 (2(+)) and 2.006 (3(+)), which is indicative of a main α-diimine radical character of the compounds. Both the anions and cations exhibit charge transfer transitions of low to moderate intensity in their visible spectrum. Quantum chemical calculations (B3LYP) reproduce both the g-values and Vis-NIR spectra of the complexes. The radical anions readily react with dioxygen to give the radical cations. 2(+) catalyzes the aerobic oxidation of benzyl alcohol into benzaldehyde.

  15. Understanding the Action of Indolizines as Biologically Active Moieties: A Molecular Dynamics Study.

    PubMed

    Szefler, Beata; Czelen, Przemyslaw; Diudea, Mircea V

    2017-01-01

    Indolizines represent a class of heteroaromatic compounds, of pharmacological importance, containing two condensed 5- and 6-memebered rings bridged by a nitrogen atom. Despite indolizine is an important medicinal moiety, a detailed view on the mechanism of action of biologically active indolizines is unavailable. The study of ligand-enzyme affinity is of high interest; description of characteristics (energetic and geometric ones) of ligand binding to the active sites of an enzyme could be useful in understanding the action mechanism of a given ligand on the concerned enzyme. After conducting a QSAR study, to predict IC50 (on 15-LO protein from soybeans) of indolizine derivatives and a docking study of indolizines on Beta lactamase and Nicotinamide phosphoribosyltransferase proteins [1], a molecular dynamics analysis was performed on one of the indolizine derivatives, complexed to the above proteins. The performed molecular dynamics study led to the identification of interactions responsible for the stabilization of complexes of the chosen ligand (i.e., indolizine derivative) with the considered enzymes and the specificity of the ligand interaction as well. The structural data and enthalpy values clearly indicate the differences in the behavior of ligand at the active sites of the three investigated enzymes. Among the studied proteins, the hydrophobicity of the active site of Nicotinamide phosphoribosyltransferase seems to be the main factor in promoting the interaction enzyme-ligand, much more manifested in this case, in comparison to the other two proteins Beta lactamase and Nicotinamide phosphoribosyltransferase. The present paper discusses a possible mechanism of interaction of an indolizine derivative with three enzyme proteins, providing information for future work in this topic. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  16. An approach to water molecule dynamics associated with motion of catalytic moiety

    NASA Astrophysics Data System (ADS)

    Shimahara, Hideto; Sugimori, Kimikazu; Koyimatu, Muhmad; Nagao, Hidemi; Ohkubo, Tadayasu; Kobayashi, Yuji

    2013-02-01

    A water bridge composed of several water molecules between the catalytic moieties, His64 and the zinc-bound solvent, in human carbonic anhydrase II (hCAII) is disrupted when the inhibitor acetazolamide (ACZ) binds to the zinc ion, according to the crystallographic structure of the ACZ-hCAII complex. In this structure, the ACZ methyl group is far (˜10 Å) from the His64. However, this binding causes an 1H NMR chemical shift change (˜1 ppm) in His64 in solution. This suggests two alternative mechanisms: a) the ACZ methyl group may be closer to His64 in the complex in solution, compared to the crystal, or b) the disruption of the water bridge might cause the His64 to move or behave in a different manner. The binding of ACZ to the enzyme in solution was examined by observing the NMR signals of the 13C-labeled ACZ methyl group in the ACZ-hCAII complex. The 13C signals of the free and bound forms were detected. In the bound form, the signal for the acetamide group was pH dependent, whereas the sulfonamide group signal was pH independent. Some 13C-filtered NOE signals were observed, although none of the signals were related to the His64 chemical shift. Based on these observations, we suggest that the position or motion of His64 is associated with disruption of the water bridge in the ACZ-hCAII complex in solution, which could change the 1H chemical shift.

  17. Influence of the carbohydrate moieties on the immunoreactivity and digestibility of the egg allergen ovomucoid.

    PubMed

    Benedé, Sara; López-Fandiño, Rosina; Reche, Marta; Molina, Elena; López-Expósito, Iván

    2013-01-01

    Ovomucoid (OM) has two carbohydrate chains on each of the first and second domains and one in the third. The contribution of the covalently bound carbohydrate chains to the overall OM allergenicity is controversial. Another aspect directly related with the immunological properties of OM that has not been studied in depth is the importance of the carbohydrate chains on its digestibility. The aim of the study was to assess the involvement of the carbohydrate moieties of OM in its digestibility and allergenic properties. IgE-binding and basophil activation by glycosylated and enzymatically deglycosylated OM (dOM) were compared using blood from egg-allergic patients. The peptides obtained after digestion using a physiologically relevant model were identified by RP-HPLC-MS/MS and the IgE-binding of the resulting fragments was evaluated by DOT-Blot. No structural changes were observed after deglycosylation of OM. 80% of the patients showed lower IgE binding to dOM as compared with OM and, in some patients, IgE reactivity could not be inhibited by pre-incubation with dOM. A subtle reduction in the percentage of activated basophils was observed when incubated with dOM as compared to OM. Following simulated digestion, dOM was more extensively degraded than OM, particularly during the gastric phase and both, OM and dOM, yielded, after the duodenal phase, immunoreactive fragments that were totally or partially coincident with previously described epitopes. this work demonstrated an enhanced IgE reactivity towards carbohydrate containing OM in some egg-allergic patients that could be attributed to cross-sensitization or sensitization to the glycosylated components. The carbohydrate chains contributed to an increased resistance to proteolysis, and thus, to its allergenic potency. Evaluation of the products of digestion of OM and dOM revealed the presence of high-frequency IgE-binding epitopes that could remain linked by disulphide bonds.

  18. NASA Technical Standards Program

    NASA Technical Reports Server (NTRS)

    Gill, Paul S.; Vaughan, William W.; Parker, Nelson C. (Technical Monitor)

    2002-01-01

    The NASA Technical Standards Program was officially established in 1997 as result of a directive issued by the Administrator. It is responsible for Agency wide technical standards development, adoption (endorsement), and conversion of Center-unique standards for Agency wide use. One major element of the Program is the review of NSA technical standards products and replacement with non-Government Voluntary Consensus Standards in accordance with directions issued by the Office of Management and Budget. As part of the Program's function, it developed a NASA Integrated Technical Standards Initiative that consists of and Agency wide full-text system, standards update notification system, and lessons learned-standards integration system. The Program maintains a 'one stop-shop' Website for technical standards ad related information on aerospace materials, etc. This paper provides information on the development, current status, and plans for the NAS Technical Standards Program along with metrics on the utility of the products provided to both users within the nasa.gov Domain and the Public Domain.

  19. NASA Technical Standards Program

    NASA Technical Reports Server (NTRS)

    Gill, Paul S.; Vaughan, WIlliam W.

    2003-01-01

    The NASA Technical Standards Program was officially established in 1997 as result of a directive issued by the Administrator. It is responsible for Agency wide technical standards development, adoption (endorsement), and conversion of Center-unique standards for Agency wide use. One major element of the Program is the review of NSA technical standards products and replacement with non-Government Voluntary Consensus Standards in accordance with directions issued by the Office of Management and Budget. As part of the Program s function, it developed a NASA Integrated Technical Standards Initiative that consists of and Agency wide full-text system, standards update notification system, and lessons learned - standards integration system. The Program maintains a "one stop-shop" Website for technical standards ad related information on aerospace materials, etc. This paper provides information on the development, current status, and plans for the NAS Technical Standards Program along with metrics on the utility of the products provided to both users within the nasa.gov Domain and the Public Domain.

  20. 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.

  1. 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.

  2. 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

  3. Interaction of the aziridine moiety of RSU-1069 with nucleotides and inorganic phosphate. Implications for alkylation of DNA.

    PubMed

    Silver, A R; O'Neill, P

    1986-04-01

    The aziridine moiety of RSU-1069 (1-(2-nitro-1-imidazolyl)-3-(1-aziridino-2-propanol] alkylates inorganic phosphate and a range of nucleotides in aqueous solutions of pH 7.0. From the rate constants obtained and a study of the adducts formed it is demonstrated that phosphate is a major target on nucleotides at neutral pH, although additional sites may exist particularly on dGMP and dAMP. From the dependence of reactivity on pH and the influence of ionic strength, it is established that the protonated aziridine is the reactive species and that hydrolysis is insignificant when compared to the rate of phosphorylation. The reaction kinetics detailed in this study are discussed in terms of DNA alkylation and strand breakage effected by the aziridine moiety of RSU-1069.

  4. Transfection of Antisense Oligonucleotides Mediated by Cationic Vesicles Based on Non-Ionic Surfactant and Polycations Bearing Quaternary Ammonium Moieties

    PubMed Central

    Mayr, Judith; Grijalvo, Santiago; Bachl, Jürgen; Pons, Ramon; Eritja, Ramon; Díaz Díaz, David

    2017-01-01

    Three different ionene polymers with varying quaternary ammonium moieties were used as a proof of concept for the formulation of antisense oligonucleotides, which are capable of inhibiting Renilla luciferase messenger ribonucleic acid (mRNA). Cationic vesicles, consisting of cationic polymer, antisense oligonucleotide (Luc) and non-ionic surfactant polysorbate 80, were investigated regarding their ζ potential, cytotoxicity and transfection efficiency. Deoxyribonucleic acid- (DNA) forming complexes in the presence of cationic vesicles were also investigated in terms of small-angle X-ray scattering (SAXS). The studied cationic vesicles showed very little, if any, toxicity against HeLa cells. Transfection abilities proved to vary strongly depending on the present quaternary ammonium moiety. PMID:28587106

  5. Synthesis and in vitro antiproliferative activity of new 1,3,4-oxadiazole derivatives possessing sulfonamide moiety.

    PubMed

    Gamal El-Din, Mahmoud M; El-Gamal, Mohammed I; Abdel-Maksoud, Mohammed S; Yoo, Kyung Ho; Oh, Chang-Hyun

    2015-01-27

    Synthesis of a new series of 1,3,4-oxadiazole derivatives possessing sulfonamide moiety is described. Their in vitro antiproliferative activities against NCI-58 human cancer cell lines of nine different cancer types were tested. Compound 1k with p-methoxybenzenesulfonamido moiety showed the highest mean %inhibition value over the 58 cell line panel at 10 μM concentration. It showed broad-spectrum antiproliferative activity over many cell lines of different cancer types. For instance, compound 1k inhibited the growth of T-47D breast cancer cell line by 90.47% at 10 μM. And it inhibited growth of SR leukemia, SK-MEL-5 melanoma, and MDA-MB-468 breast cancer cell lines by more than 80% at the same test concentration. Compound 1k showed superior activity than Paclitaxel and Gefitinib against the most sensitive cell lines.

  6. Synthesis and biological evaluation of novel fluconazole analogues bearing 1,3,4-oxadiazole moiety as potent antifungal agents.

    PubMed

    Liao, Jun; Yang, Fan; Zhang, Lei; Chai, Xiaoyun; Zhao, Qingjie; Yu, Shichong; Zou, Yan; Meng, Qingguo; Wu, Qiuye

    2015-04-01

    A novel series of fluconazole based mimics incorporating 1,3,4-oxadiazole moiety were designed and synthesized. All the title compounds were characterized by (1)H-NMR, (13)C-NMR, and Q-TOF-MS. Preliminary results revealed that most of analogues exhibited significant antifungal activity against seven pathogenic fungi. Compounds 9g and 9k (MIC80 ≤ 0.125 μg/mL, respectively) were found more potent than the positive controls itraconazole and fluconazole as broad-spectrum antifungal agents. The observed docking results showed that the 1,3,4-oxadiazole moiety enhanced the affinity binding to the cytochrome P450 14α-demethylase (CYP51).

  7. Transfection of Antisense Oligonucleotides Mediated by Cationic Vesicles Based on Non-Ionic Surfactant and Polycations Bearing Quaternary Ammonium Moieties.

    PubMed

    Mayr, Judith; Grijalvo, Santiago; Bachl, Jürgen; Pons, Ramon; Eritja, Ramon; Díaz Díaz, David

    2017-05-26

    Three different ionene polymers with varying quaternary ammonium moieties were used as a proof of concept for the formulation of antisense oligonucleotides, which are capable of inhibiting Renilla luciferase messenger ribonucleic acid (mRNA). Cationic vesicles, consisting of cationic polymer, antisense oligonucleotide (Luc) and non-ionic surfactant polysorbate 80, were investigated regarding their ζ potential, cytotoxicity and transfection efficiency. Deoxyribonucleic acid- (DNA) forming complexes in the presence of cationic vesicles were also investigated in terms of small-angle X-ray scattering (SAXS). The studied cationic vesicles showed very little, if any, toxicity against HeLa cells. Transfection abilities proved to vary strongly depending on the present quaternary ammonium moiety.

  8. Synthesis and characterization of anion exchange multi-block copolymer membranes with a fluorine moiety as alkaline membrane fuel cells

    NASA Astrophysics Data System (ADS)

    Kim, Eunyoung; Lee, Sojeong; Woo, Seunghee; Park, Seok-Hee; Yim, Sung-Dae; Shin, Dongwon; Bae, Byungchan

    2017-08-01

    Multi-block copolymers containing a partially fluorinated hydrophobic moiety (F-PE) are synthesized for application as alkaline membrane fuel cells (AMFCs). The partially fluorinated monomer is synthesized by palladium-catalyzed Suzuki coupling, and quaternary ammonium groups are introduced after selective chloromethylation of the hydrophilic blocks. TEM investigation of the block copolymers show well-defined hydrophilic-hydrophobic phase separation behavior, resulting in high anion conductivity. In particular, the partially fluorinated hydrophobic blocks are stable even after immersing into a 1 M KOH solution because the hydrophobicity of the fluorine moiety excludes hydrophilic nucleophiles, which are the main sources of chemical degradation of AEMs. Although the hydrophilic domains are slightly degraded under harsh alkaline conditions, the F-PE survives at room temperature in a 1 M KOH solution for 720 h. F-PE membranes result in an AMFC performance of 310 mA cm-2 at 0.6 V and 70 °C.

  9. 1981 Bibliography of Technical Writing.

    ERIC Educational Resources Information Center

    Book, Virginia Alm; And Others

    1982-01-01

    Offers resources on technical writing published in 1981. Arranges the citations under the following categories: bibliographies, books, reviews, and articles on the profession; theory and philosophy; pedagogy; technical speech; research; designing degree programs; technical writing and the computer; writing technical articles and reports;…

  10. 1980 Bibliography of Technical Writing.

    ERIC Educational Resources Information Center

    Book, Virginia Alm; And Others

    1981-01-01

    Offers resources on technical writing that were published in 1980. Arranges the citations under 12 categories: bibliographies, books, reviews, and articles on theory and philosophy; pedagogy; writing technical articles and reports; research; technical writing and the computer; graphic/visual aids; correspondence; technical speech; and designing…

  11. Technical Subjects in Secondary Schools

    ERIC Educational Resources Information Center

    Howard, A. E.

    2008-01-01

    Purpose: This paper aims to examine technical education in various types of secondary schools, and suggests three levels of technical courses to be taught in secondary schools. Design/methodology/approach: The paper discusses the differences between technical schools and colleges, and vocational technical courses taught in "academic"…

  12. 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.

  13. 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

  14. [Spin-spin interaction upon introduction of a spin label into immunoglobulins M and G at the carbohydrate moiety].

    PubMed

    Timofeev, V P; Nikol'skiĭ, D O; Lapuk, V A; Aleshkin, V A

    2002-01-01

    By spin labeling the monoclonal IgM and normal IgG at the carbohydrate moiety with 2,2,6,6-tetramethyl-4-aminopiperidine-1-oxyl, preparations were obtained whose ESR spectra indicate rapid exchange spin-spin interactions between two spin labels. It was shown that, in the case of spin-labeled IgM, this spectrum is determined by a glycopeptide noncovalently bound to IgM, which incorporates two spin labels.

  15. Reaction mechanisms in aromatic hydrocarbon formation involving the C{sub 5}H{sub 5} cyclopentadienyl moiety

    SciTech Connect

    Melius, C.F.; Colvin, M.E.; Marinov, N.M.; Pitz, W.J.; Senkan, S.M.

    1996-02-01

    The quantum chemical BAC-MP4 and BAC-MP2 methods have been used to investigate the reaction mechanisms leading to polycyclic aromatic hydrocarbon (PAH) ring formation. In particular the authors have determined the elementary reaction steps in the conversion of two cyclopentadienyl radicals to naphthalene. This reaction mechanism is shown to be an extension of the mechanism occurring in the H atom-assisted conversion of fulvene to benzene. The net reaction involves the formation of dihydrofulvalene, which eliminates a hydrogen atom and then rearranges to form naphthalene through a series of ring closures and openings. The importance of forming the {single_bond}CR({center_dot}){single_bond}CHR{single_bond}CR{prime}{double_bond}CR{double_prime}-moiety, which can undergo rearrangement to form three-carbon-atom ring structures, is illustrated with the C{sub 4}H{sub 7} system. The ability of hydrogen atoms to migrate around the cyclopentadienyl moiety is illustrated both for methyl-cyclopentadiene, C{sub 5}H{sub 5}CH{sub 3}, and dihydrofulvalene, C{sub 5}H{sub 5}C{sub 5}H{sub 5}, as well as for their radical species, C{sub 6}H{sub 7} and C{sub 5}H{sub 5}C{sub 5}H{sub 4}. The mobility of hydrogen in the cyclopentadienyl moiety plays an important role both in providing resonance-stabilized radical products and in creating the {single_bond}CR({center_dot}){single_bond}CHR{single_bond}CR{prime}{double_bond}CR{double_prime}-moiety for ring formation. The results illustrate the radical pathway for converting five-membered rings to aromatic six-membered rings. Furthermore, the results indicate the important catalytic role of H atoms in the aromatic ring formation process.

  16. Dragmacidins G and H, Bisindole Alkaloids Tethered by a Guanidino Ethylthiopyrazine Moiety, from a Lipastrotethya sp. Marine Sponge.

    PubMed

    Hitora, Yuki; Takada, Kentaro; Ise, Yuji; Okada, Shigeru; Matsunaga, Shigeki

    2016-11-23

    LCMS analysis of the extract and a cytotoxicity assay of the HPLC fractions generated from a small-scale extract of a Lipastrotethya sp. marine sponge demonstrated the presence of bisindole alkaloids that were associated with the cytotoxic activity. Two bisindole alkaloids tethered by a guanidino ethylthiopyrazine moiety, dragmacidins G (1) and H (2), were isolated, and their structures were assigned by analysis of the MS and NMR data. They showed moderate cytotoxic activity against HeLa cells.

  17. Antimicrobial and Hemolytic Studies of a Series of Polycations Bearing Quaternary Ammonium Moieties: Structural and Topological Effects

    PubMed Central

    Mayr, Judith; Bachl, Jürgen; Schlossmann, Jens; Díaz Díaz, David

    2017-01-01

    A series of polycations bearing quaternary ammonium moieties have shown antimicrobial activity against the Gram-negative bacterium Escherichia coli. Different polymer topologies governed by a disubstituted aromatic core as well as different diamine-based linkers were found to influence the antimicrobial properties. Moreover, the hemolytic activity against human red blood cells was measured and demonstrated good biocompatibility and selectivity of these polycations for bacteria over mammalian cells. PMID:28146105

  18. Polycycloiridals A-D, Four Iridal-Type Triterpenoids with an α-Terpineol Moiety from Iris tectorum.

    PubMed

    Zhang, Chun-Lei; Liu, Yan-Fei; Wang, Yan; Liang, Dong; Jiang, Zhi-Bo; Li, Li; Hao, Zhi-You; Luo, Huan; Shi, Guo-Ru; Chen, Ruo-Yun; Cao, Zheng-Yu; Yu, De-Quan

    2015-11-20

    Polycycloiridals A-D, four novel iridals with an unprecedented α-terpineol moiety resulting from cyclization of the homofarnesylside chain, were isolated from the ethanol extract of rhizomes of Iris tectorum. Their structures were elucidated on the basis of comprehensive spectroscopic analysis. The absolute configuration of 1 was determined by the modified Mosher's method and comparison of experimental and calculated electronic circular dichroism (ECD) spectrum. A possible biosynthetic pathway was postulated.

  19. Generation of light-induced electrical potential from ion exchange membranes containing 4,4{prime}-bipyridine moiety

    SciTech Connect

    Sata, Toshikatsu

    1996-07-15

    Ion exchange membranes, which are some of the most advanced separation membranes, are widely used in industry, i.e., in electrodialysis processes, diffusion dialysis processes, as separators for electrolysis, solid polyelectrolytes for fuel cells, etc. Generation of photovoltage and photocurrent from ion exchange membranes containing a viologen moiety was examined, cation exchange membranes ion-exchanged with methyl viologen and anion exchange membranes to which a viologen moiety was bonded. After the membrane, swelled with ethylene glycol, had been clamped between two ITO electrodes and sealed, it was irradiated with a xenon lamp. In the case of the cation exchange membranes ion-exchanged with methyl viologen, 155.3 mV of photo-voltage was observed immediately after photoirradiation, and the voltage decreased and attained almost a constant value. The photovoltage of anion exchange membranes with the viologen moiety increased very slowly (maximum 81 mV, 405 nA; load resistance 200 K{Omega}) after beginning the irradiation. However, when the light was irradiated again on the membrane after interruption of the irradiation, almost the same photovoltage was generated immediately after the irradiation. Though the anion exchange membrane showed absorbance only at 320 nm in the UV-VIS spectrum, wavelengths between 300 and 400 nm were active to reduce the viologen moiety of the membrane. This might be due to a polymer effect. On the other hand, the electrical resistance between the ITO electrodes decreased upon photoirradiation because of radical formation. In order to accelerate generation of the voltage, an oxidative agent (ferric ions) or a reductive agent (triethanolamine) was added to the system. The photovoltage was generated immediately after irradiation in both cases. Ferric ions act as an electron acceptor and triethanolamine forms cation radicals in the membrane before the irradiation.

  20. Inhibition of the ribosomal peptidyl transferase reaction by the mycarose moiety of the antibiotics carbomycin, spiramycin and tylosin.

    PubMed

    Poulsen, S M; Kofoed, C; Vester, B

    2000-12-01

    Many antibiotics, including the macrolides, inhibit protein synthesis by binding to ribosomes. Only some of the macrolides affect the peptidyl transferase reaction. The 16-member ring macrolide antibiotics carbomycin, spiramycin, and tylosin inhibit peptidyl transferase. All these have a disaccharide at position 5 in the lactone ring with a mycarose moiety. We have investigated the functional role of this mycarose moiety. The 14-member ring macrolide erythromycin and the 16-member ring macrolides desmycosin and chalcomycin do not inhibit the peptidyl transferase reaction. These drugs have a monosaccharide at position 5 in the lactone ring. The presence of mycarose was correlated with inhibition of peptidyl transferase, footprints on 23 S rRNA and whether the macrolide can compete with binding of hygromycin A to the ribosome. The binding sites of the macrolides to Escherichia coli ribosomes were investigated by chemical probing of domains II and V of 23 S rRNA. The common binding site is around position A2058, while effects on U2506 depend on the presence of the mycarose sugar. Also, protection at position A752 indicates that a mycinose moiety at position 14 in 16-member ring macrolides interact with hairpin 35 in domain II. Competitive footprinting of ribosomal binding of hygromycin A and macrolides showed that tylosin and spiramycin reduce the hygromycin A protections of nucleotides in 23 S rRNA and that carbomycin abolishes its binding. In contrast, the macrolides that do not inhibit the peptidyl transferase reaction bind to the ribosomes concurrently with hygromycin A. Data are presented to argue that a disaccharide at position 5 in the lactone ring of macrolides is essential for inhibition of peptide bond formation and that the mycarose moiety is placed near the conserved U2506 in the central loop region of domain V 23 S rRNA.

  1. Asymmetric induction by the cholestanic moiety on tropos species: synthesis and stereochemical characterization of bile acid-based biphenyl phosphites.

    PubMed

    Iuliano, A; Facchetti, S; Uccello-Barretta, G

    2006-06-23

    Three different bile acid-derived biphenyl phosphites were synthesized, starting from cholic and deoxycholic acids and biphenol, and their stereochemical features were checked by CD and NMR spectroscopies. On the basis of the spectroscopic results, the capability of the cholestanic system to induce a prevalent sense of twist on the biphenyl moiety of the bile acid-derived phosphites as well as their tropos nature was inferred.

  2. Glycosidic moiety changes the spectroscopic properties of DL-α-tocopherol in DMSO/water solution and in organic solvents

    NASA Astrophysics Data System (ADS)

    Neunert, G.; Polewski, P.; Walejko, P.; Markiewicz, M.; Witkowski, S.; Polewski, K.

    2009-07-01

    In this study we estimated how conjugation with a sugar moiety influences the spectral properties of tocopherol and relate the spectroscopic properties of glycosides to solvent properties such as viscosity and polarity. Spectroscopic properties (absorption, fluorescence, fluorescence anisotropy and fluorescence lifetime) of three DL-α-tocopheryl glycosides (DL-α-tocopheryl orthoacetate derivative and glycosides of DL-α-tocopherol model compounds: 2,2,5,7,8-pentamethyl-6-chromanol and Trolox) were studied in DMSO/water solution. In all investigated compounds dissolved in DMSO/water mixture the absorption and emission maxima were blue-shifted. The fluorescence lifetimes were longer compared with those obtained for the parent compounds, except for the Trolox glucoside, in which it was shorter. The observed effect is connected with an increase in the electronic energy in the ground state due to electron rearrangement in the chromanol system caused by interaction with the sugar moiety. The extent of the spectral shift is related to the sugar moiety substituted at the phenolic oxygen rather than to substitution at the 2a position in the chromanol ring. The fluorescent properties of DL-α-tocopheryl glucoside in organic solvents were measured. The Stokes shift was related to the orientational polarizability of the solvents. The study of viscosity suggested two different mechanisms explaining the results observed in a low- and high-viscosity environment. The results indicated the fundamental role of interactions between the chromophore and sugar moiety in a low-viscosity environment. The results obtained at high values of viscosity are discussed in terms of a frictional boundary solvent-solute interaction model.

  3. Synthesis and Characterization of a Series of Alternating Copolymers (Oligomers) Containing Organophospha-lambda5-azene Backbone Moieties

    DTIC Science & Technology

    1989-04-03

    ORGANIZATION The University of Texas Offic of NaalcReearc at Arlington Ofc fNvlRsac 6C- ADDRESS (City, Stare, and ZIP Coce) 7b. ADDRESS (Lay, State, ad...ZIP Coae) Department of Chemistry, Box 1906580NotQunySre The University of Texas at Arlington 800inothn Viuin Street Arlington, Texas 76019...Moieties Accession For NTIS GRA&I DTIC TABUnannouac ed El Martin Pomerantz* and Mark W. Victor ustiocation Department of Chemistry The University of

  4. 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.

  5. The Synthesis and Evaluation of Third-Order Optical Nonlinearities of Model Compounds Containing Benzothiazole, Benzimidazole and Benzoxazole Moieties.

    DTIC Science & Technology

    1991-02-01

    AD-A235 622 WL-TR-91-4015 THE SYNTHESIS AND EVALUATION OF THIRD-ORDER OPTICAL NONLINEARITIES OF MODEL COMPOUNDS CONTAINING BENZOTHIAZOLE ...Nonlinearities of Model Compounds Containing Benzothiazole , Benzimidazole, and Benzoxazole Moieties 12 PERSONAL AUTHOR(S) Bruce A. Reinhardt, Marilyn R...necessary and identify by block number) FIELD GROUP SUB-GROUP nonlinear optical properties benzothiazole u/ 03 degenerate four-wave mixing benzimidazole 21

  6. Amino(oxo)acetate moiety: A new functional group to improve the cytotoxicity of betulin derived carbamates.

    PubMed

    Heller, Lucie; Perl, Vincent; Wiemann, Jana; Al-Harrasi, Ahmed; Csuk, René

    2016-06-15

    While 3-O-acetylated betulin derivatives carrying a carbamate moiety at position C-28 are of rather low cytotoxicity for human tumor cell lines, the corresponding C-3 amino(oxo) acetates show good cytotoxicity. For example, an EC50 as low as 2.0μM was found for (3β) 28-{[(hexylamino)carbonyl]oxy}lup-20(29)-en-3-yl amino(oxo)acetate (16) employing the ovarian cancer cell line A2780.

  7. Analysis of the lipid moiety of lipopolysaccharide from Rhizobium tropici CIAT899: identification of 29-hydroxytriacontanoic acid.

    PubMed Central

    Gil-Serrano, A M; González-Jiménez, I; Tejero-Mateo, P; Megías, M; Romero-Vazquez, M J

    1994-01-01

    The lipid moieties of two lipid A's isolated from the phenolic and aqueous fractions of lipopolysaccharide from Rhizobium tropici CIAT899 have been studied. Several 3-hydroxy fatty acids and two long-chain hydroxy fatty acids, 27-hydroxyoctacosanoic acid, and 29-hydroxytriacontanoic acid were identified; the ratios of these acids are the same in both lipid A's. These results can be used for chemotaxonomic purposes. PMID:8157617

  8. Can the Excited State Energy of a Pyrenyl Unit Be Directly Transferred to a Perylene Bisimide Moiety?

    PubMed

    Wang, Gang; Shang, Congdi; Wang, Li; Peng, Haonan; Yin, Shiwei; Fang, Yu

    2016-11-23

    A pyrenyl unit (Py) was chemically connected to a perylene bisimide (PBI) moiety through a long and flexible linker, 4,7,10-trioxa-1,13-tridecanediamine (TOA), resulting in a fluorescent dyad, PBI-TOA-Py. Ultraviolet-visible absorption and fluorescence studies revealed that the two fluorescent units of PBI-TOA-Py behave independently. However, efficient Förster resonance energy transfer (FRET) from the Py unit to the PBI moiety in solution state was also observed. Temperature and solvent effect studies demonstrated that the energy transfer efficiency is highly dependent upon solution temperature and solvent nature. Specifically, for the dimethylformamide (DMF) solution of PBI-TOA-Py, the FRET efficiency is close to 88% at temperatures below ∼40 °C, but the efficiency greatly decreases to nearly zero when the temperature exceeds ∼80 °C. Moreover, addition of HAc into the DMF solution at room temperature could reduce the energy transfer efficiency to nearly zero, suggesting that the excited state energy of Py cannot be directly transferred to the PBI structure even though they are properly and chemically bonded. On the basis of the observations and time-resolved studies, it is believed that the observed efficient FRET from the Py unit to the PBI moiety occurs mainly through Py excimer formation, which could be a result of intermolecular association of the compound. Thus, the applications of the fluorescent dyad in solvent discrimination and trace water determination in organic solvents were verified through example studies.

  9. Synthesis and properties of mRNA cap analogs containing phosphorothioate moiety in 5',5'-triphosphate chain.

    PubMed

    Kowalska, Joanna; Lewdorowicz, Magdalena; Zuberek, Joanna; Bojarska, Elzbieta; Wojcik, Jacek; Cohen, Lean S; Davis, Richard E; Stepinski, Janusz; Stolarski, Ryszard; Darzynkiewicz, Edward; Jemielity, Jacek

    2005-01-01

    Nucleosides and oligonucleotides with an oxygen replaced by sulfur atom are an interesting class of compounds because of their improved stability toward enzymatic cleavage by nucleases. We have synthesized several dinucleotide mRNA cap analogs containing a phosphorothioate moiety in the alpha, beta, or gamma position of 5',5'-triphosphate chain [m7Gp(s)ppG, m7Gpp(s)pG, and m7Gppp(s)G]. These are the first examples of the biologically important 5'mRNA cap analogs containing a phosphorothioate moiety, and these compounds may be useful in a variety of biochemical and biotechnological applications. Incorporation of a sulfur atom in the alpha or gamma position within the dinucleotide cap analog was achieved using PSCl3 in a nucleoside phosphorylation reaction followed by coupling the phosphorothioate of nucleoside with a second nucleotide. Synthesis of cap analogs with the phosphorothioate moiety in beta position was performed using an organic phosphorothioate salt in a coupling reaction with an activated nucleotide. The structures of newly synthesized compounds was confirmed using MS and 1H and 31P NMR spectroscopy. We present here the results of preliminary studies on their interaction with translation initiation factor eIF4E and enzymatic hydrolysis with human and nematode DcpS scavengers.

  10. Tea catechins with a galloyl moiety suppress postprandial hypertriacylglycerolemia by delaying lymphatic transport of dietary fat in rats.

    PubMed

    Ikeda, Ikuo; Tsuda, Koichi; Suzuki, Yuko; Kobayashi, Makoto; Unno, Tomonori; Tomoyori, Hiroko; Goto, Hitomi; Kawata, Yayoi; Imaizumi, Katsumi; Nozawa, Ayumu; Kakuda, Takami

    2005-02-01

    Tea catechins, (-)-epicatechin (EC), (-)-epigallocatechin (EGC), (-)-epicatechin gallate (ECG), and (-)-epigallocatechin gallate (EGCG), have been shown to be epimerized to (-)-catechin (C), (-)-gallocatechin (GC), (-)-catechin gallate (CG), and (-)-gallocatechin gallate (GCG), respectively, during heat treatment. In this study, we examined the effect of tea catechins rich in ECG and EGCG and heat-treated tea catechins rich in CG and GCG on postprandial hypertriacylglycerolemia in rats. Both tea catechins and heat-treated tea catechins suppressed postprandial hypertriacylglycerolemia. Lymphatic recovery of (14)C-trioleoylglycerol in rats cannulated in the thoracic duct was delayed by the administration of tea catechins and heat-treated tea catechins. Tea catechins and heat-treated tea catechins had the same effect on all variables tested. These catechin preparations dose-dependently inhibited the activity of pancreatic lipase in vitro. When purified catechins were used, only those with a galloyl moiety inhibited the activity of pancreatic lipase. These results suggest that catechins with a galloyl moiety suppress postprandial hypertriacylglycerolemia by slowing down triacylglycerol absorption through the inhibition of pancreatic lipase. Because postprandial hypertriacylglycerolemia is a risk factor for coronary heart disease, our results suggest that catechins with a galloyl moiety may prevent this disease.

  11. Potential roles of myeloperoxidase and hypochlorous acid in metabolism and toxicity of alkene hydrocarbons and drug molecules containing olefinic moieties.

    PubMed

    Zhang, Xin-Yu; Elfarra, Adnan A

    2017-05-01

    Adverse drug reactions (ADRs) pose a significant health problem and are generally attributed to reactive metabolites. Olefinic moieties in drugs can undergo cytochrome P450-mediated bioactivation to produce reactive metabolites but myeloperoxidase (MPO)-mediated bioactivation of these moieties has not been reported. Thus, small molecules of alkene hydrocarbons are used as model compounds to characterize the MPO-mediated metabolism. Areas covered: The authors focus on MPO-mediated metabolism of alkene hydrocarbons to form chlorohydrins and the potential role of chlorohydrins in alkene toxicity and carcinogenicity. A case study is presented, in which a carcinogenic alkene, 1,3-butadiene, is demonstrated to form 1-chloro-2-hydroxy-3-butene (CHB) through the MPO-mediated pathway. Further bioactivation of CHB yields a cross-linking metabolite, 1-chloro-3-buten-2-one (CBO), which is highly reactive toward glutathione, proteins, nucleosides, and DNA. Toxicity and mutagenicity of CHB and CBO are also presented. Expert opinion: Alkene hydrocarbons readily undergo MPO-mediated bioactivation to form chlorohydrins, which can further be biotransformed into proteins/DNA-modifying reactive metabolites. Therefore, chlorohydrin formation may play an important role in alkene toxicity and carcinogenicity. Olefinic moieties in drugs are expected to undergo similar bioactivation, which may contribute to ADRs. Studies to investigate the roles of MPO and chlorohydrin formation in ADRs are thus warranted.

  12. Surface hydrophilic modification with a sugar moiety for a uniform-sized polymer molecularly imprinted for phenobarbital in serum.

    PubMed

    Hua, Kuichang; Zhang, Lei; Zhang, Zhenhui; Guo, Yong; Guo, Tianying

    2011-08-01

    A uniform-sized polymer molecularly imprinted for phenobarbital, which is surface modified by a sugar moiety, has been prepared through a two-step swelling polymerization method using polystyrene beads as seeds, phenobarbital as the template, 4-vinylpyridine as a functional monomer, ethylene glycol dimethacrylate as a cross-linker and 2-O-meth-acryloyloxyethoxyl-(2,3,4,6- tetra-O-acetyl-β-d-galactopyranosyl)-(1-4)-2,3,6-tri-O-acetyl-β-d-glucopyranoside as a surface-modifying glycomonomer, respectively. After deprotecting the glycopolymer, a surface sugar moiety-modified, hydrophilic, molecularly imprinted polymer for phenobarbital (glyco-MIP) was obtained. The resulting polymer beads were packed into a stainless steel column to evaluate their chromatographic characteristics by high-performance liquid chromatography (HPLC). Good selectivity for phenobarbital was obtained with the glyco-MIP compared to the unmodified molecularly imprinted polymer, which revealed that the recognition sites of phenobarbital were unchanged with sugar moiety surface modification. Furthermore, bovine serum albumin was almost completely recovered from the glyco-MIP column, which indicates that the glyco-MIP materials can be used to separate and analyze drugs in complex samples, such as biological samples. The results of pretreatment with and analysis of phenobarbital in serum suggest that this material can be used to analyze phenobarbital in serum through a pretreatment and reverse-phase HPLC analysis process. Copyright © 2011 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  13. Multivalent agents containing 1-substituted 2,3,4-trihydroxyphenyl moieties as novel synthetic polyphenols directed against HIV-1.

    PubMed

    Flores, Aida; Camarasa, María José; Pérez-Pérez, María Jesús; San-Félix, Ana; Balzarini, Jan; Quesada, Ernesto

    2014-07-28

    The synthesis and the assessment of the anti-HIV activity of a set of molecules inspired by the multivalent structures of some naturally-occurring polyphenols (tannins) are reported. Different multibranched scaffolds have been derived from pentaerythritol as the central core which distribute spatially synthetic polyphenolic subunits based on 1-substituted 2,3,4-trihydroxyphenyl moieties. A tetrapodal compound () bearing four N-(2,3,4-trihydroxyphenyl)amide groups, exhibits remarkable selective activity against HIV-1 with EC50 values in the micromolar scale, in the same range as those reported for the most representative anti-HIV tannins. Preliminary SAR studies emphasize the importance of the 1-substituted 2,3,4-trihydroxyphenyl moiety, the presence of an amide as the linker and the multivalent architecture of these molecules, since the anti-HIV activity increases with the number of polyphenolic moieties. The data support the interest in synthetic polyphenols and represent a promising starting point for further design and development of selective HIV-1 inhibitors.

  14. Endothelial targeting and enhanced antiinflammatory effects of complement inhibitors possessing sialyl Lewisx moieties.

    PubMed

    Mulligan, M S; Warner, R L; Rittershaus, C W; Thomas, L J; Ryan, U S; Foreman, K E; Crouch, L D; Till, G O; Ward, P A

    1999-04-15

    The complement inhibitor soluble complement receptor type 1 (sCR1) and a truncated form of sCR1, sCR1[desLHR-A], have been generated with expression of the selectin-reactive oligosaccharide moiety, sialyl Lewisx (sLex), as N-linked oligosaccharide adducts. These modified proteins, sCR1sLex and sCR1[desLHR-A]sLex, were assessed in the L-selectin- and P-selectin-dependent rat model of lung injury following systemic activation of complement by cobra venom factor and in the L-selectin-, P-selectin-, and E-selectin-dependent model of lung injury following intrapulmonary deposition of IgG immune complexes. In the cobra venom factor model, sCR1sLex and sCR1[desLHR-A]sLex caused substantially greater reductions in neutrophil accumulation and in albumin extravasation in lung when compared with the non-sLex-decorated forms. In this model, increased lung vascular binding of sCR1sLex and sCR1[desLHR-A]sLex occurred in a P-selectin-dependent manner, in contrast to the absence of any increased binding of sCR1 or sCR1[desLHR-A]. In the IgG immune complex model, sCR1[desLHR-A]sLex possessed greater protective effects relative to sCR1[desLHR-A], based on albumin extravasation and neutrophil accumulation. Enhanced protective effects correlated with greater lung vascular binding of sCR1[desLHR-A]sLex as compared with the non-sLex-decorated form. In TNF-alpha-activated HUVEC, substantial in vitro binding occurred with sCR1[desLHR-A]sLex (but not with sCR1[desLHR-A]). This endothelial cell binding was blocked by anti-E-selectin but not by anti-P-selectin. These data suggest that sLex-decorated complement inhibitors have enhanced antiinflammatory effects and appear to have enhanced ability to localize to the activated vascular endothelium.

  15. Non-imidazole histamine H3 receptor ligands incorporating antiepileptic moieties.

    PubMed

    Sadek, Bassem; Schwed, Johannes Stephan; Subramanian, Dhanasekaran; Weizel, Lilia; Walter, Miriam; Adem, Abdu; Stark, Holger

    2014-04-22

    A small series of histamine H3 receptor (H3R) ligands (1-5) incorporating different antiepileptic structural motifs has been newly synthesized. All compounds exhibited moderate to high in vitro hH3R affinities up to a sub-nanomolar concentration range with pKi values in the range of 6.25-9.62 with varying preferences for this receptor subtype. The compounds (1-5) were further investigated in vivo on anticonvulsant effects against maximum electroshock (MES)-induced and pentylenetetrazole (PTZ)-kindled convulsions in rats having phenytoin (PHT) as the reference antiepileptic drug (AED). Surprisingly, animals pretreated with 1 mg/kg, i.p. of 5,5-diphenyl-3-(3-(piperidin-1-yl)propyl)imidazolidine-2,4-dione (4) were only moderately protected and no protection was observed for compounds 1-3 and 5 in three different doses (1 mg, 5 mg, and 10 mg/kg i.p.). Compound 4 (1 mg/kg, i.p.) failed to modify PTZ-kindled convulsion. However, a dose of 10 mg/kg significantly reduced convulsions in both models. In contrast, 5,5-diphenyl-3-(4-(3-(piperidin-1-yl)propoxy)benzyl)imidazolidine-2,4-dione (5) (1, 5, and 10 mg/kg, i.p.) showed proconvulsant effects in the MES model with further confirmation of these results in the PTZ model as no protection was observed against convulsion in the doses tested (1 and 10 mg/kg). In addition, compound 4 (10 mg/kg, i.p.) significantly prolonged myoclonic latency time and shortened total convulsion duration when compared to control, PHT or standard H3R inverse agonist/antagonist pitolisant (PIT). Our results showed that H3R pharmacophores could successfully be structurally combined to antiepileptic moieties, especially phenytoin partial structures, maintaining the H3R affinity. However, the new derivatives for multiple-target approaches in epilepsy models are complex and show that pharmacophore elements are not easily pharmacologically combinable.

  16. Characterisation of the native lipid moiety of Echinococcus granulosus antigen B.

    PubMed

    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. A molecular hybrid polyoxometalate-organometallic moieties and its relevance to supercapacitors in physiological electrolytes

    NASA Astrophysics Data System (ADS)

    Chinnathambi, Selvaraj; Ammam, Malika

    2015-06-01

    Supercapacitors operating in physiological electrolytes are of great relevance for both their environmentally friendly aspect as well as the possibility to be employed for powering implantable microelectronic devices using directly biological fluids as electrolytes. Polyoxometalate (POMs) have been proven to be useful for supercapacitors in acidic media. However, in neutral pH, POMs are usually not stable. One relevant alternative is to stabilize POMs by pairing them with organic moieties to form hybrids. In this study, we combined K6P2Mo18O62·12H2O (P2Mo18) with Ru(bpy)3Cl2.6H2O (Ru(bpy)). The synthesis was carried out with and without the mild reducing agent KI. The hybrids were characterized by CHN analysis, TEM, FT-IR, XRD, TGA and cyclic voltammetry. CHN elemental analysis revealed that one mole [P2Mo18O62]6- is paired with 3 mol [Ru(bpy)3]2+ to form [Ru(bpy)3]3PMo18O62·nH2O. With KI present, [P2Mo18O62]6- is linked to 3.33 mol to yield [Ru(bpy)3]3.33PMo18O62·mH2O. Excess of Ru(bpy) in [Ru(bpy)3]3.33PMo18O62·mH2O was further confirmed by TEM, FT-IR, XRD, TGA and cyclic voltammetry. In turn, hybrid composition is found to strongly influence the supercapacitor behavior. The hybrid rich in Ru(bpy) is found to perform better for supercapacitors in physiological electrolytes. 125 F g-1 and 68 F g-1 are the capacitance values obtained with [Ru(bpy)3]3.33PMo18O62·mH2O and [Ru(bpy)3]3PMo18O62·nH2O, respectively. In terms of specific energy densities, 3.5 Wh kg-1 and 2 Wh kg-1 were obtained for both hybrid simultaneously. The difference in supercapacitor performance between both hybrids is also noticed in impedance spectroscopy which showed that [Ru(bpy)3]3.33PMo18O62·mH2O has lower electron transfer resistance if compared to [Ru(bpy)3]3PMo18O62·nH2O. Finally, if compared of parent K6P2Mo18O62·12H2O, the stability of both hybrids is found to be highly improved.

  18. 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

  19. Influence of the Carbohydrate Moieties on the Immunoreactivity and Digestibility of the Egg Allergen Ovomucoid

    PubMed Central

    Benedé, Sara; López-Fandiño, Rosina; Reche, Marta; Molina, Elena; López-Expósito, Iván

    2013-01-01

    Background Ovomucoid (OM) has two carbohydrate chains on each of the first and second domains and one in the third. The contribution of the covalently bound carbohydrate chains to the overall OM allergenicity is controversial. Another aspect directly related with the immunological properties of OM that has not been studied in depth is the importance of the carbohydrate chains on its digestibility. Objective The aim of the study was to assess the involvement of the carbohydrate moieties of OM in its digestibility and allergenic properties. Methods IgE-binding and basophil activation by glycosylated and enzymatically deglycosylated OM (dOM) were compared using blood from egg-allergic patients. The peptides obtained after digestion using a physiologically relevant model were identified by RP-HPLC-MS/MS and the IgE-binding of the resulting fragments was evaluated by DOT-Blot. Results No structural changes were observed after deglycosylation of OM. 80% of the patients showed lower IgE binding to dOM as compared with OM and, in some patients, IgE reactivity could not be inhibited by pre-incubation with dOM. A subtle reduction in the percentage of activated basophils was observed when incubated with dOM as compared to OM. Following simulated digestion, dOM was more extensively degraded than OM, particularly during the gastric phase and both, OM and dOM, yielded, after the duodenal phase, immunoreactive fragments that were totally or partially coincident with previously described epitopes. Conclusion & Clinical Relevance: this work demonstrated an enhanced IgE reactivity towards carbohydrate containing OM in some egg-allergic patients that could be attributed to cross-sensitization or sensitization to the glycosylated components. The carbohydrate chains contributed to an increased resistance to proteolysis, and thus, to its allergenic potency. Evaluation of the products of digestion of OM and dOM revealed the presence of high-frequency IgE-binding epitopes that could

  20. Technical Assistance to Developers

    SciTech Connect

    Rockward, Tommy; Borup, Rodney L.; Garzon, Fernando H.; Mukundan, Rangachary; Spernjak, Dusan

    2012-07-17

    This task supports the allowance of technical assistance to fuel-cell component and system developers as directed by the DOE. This task includes testing of novel materials and participation in the further development and validation of single cell test protocols. This task also covers technical assistance to DOE Working Groups, the U.S. Council for Automotive Research (USCAR) and the USCAR/DOE Driving Research and Innovation for Vehicle efficiency and Energy sustainability (U.S. Drive) Fuel Cell Technology Team. Assistance includes technical validation of new fuel cell materials and methods, single cell fuel cell testing to support the development of targets and test protocols, and regular advisory participation in other working groups and reviews. This assistance is made available to PEM fuel cell developers by request and DOE Approval. The objectives are to: (1) Support technically, as directed by DOE, fuel cell component and system developers; (2) Assess fuel cell materials and components and give feedback to developers; (3) Assist the DOE Durability Working Group with the development of various new material durability Testing protocols; and (4) Provide support to the U.S. Council for Automotive Research (USCAR) and the USCAR/DOE Fuel Cell Technology Team. FY2012 specific technical objectives are: (1) Evaluate novel MPL materials; (2) Develop of startup/ shutdown protocol; (3) Test the impact of hydrophobic treatment on graphite bi-polar plates; (4) Perform complete diagnostics on metal bi-polar plates for corrosion; and (5) Participate and lead efforts in the DOE Working Groups.

  1. AUAMP Resolution Issues. Technical Report

    DTIC Science & Technology

    1992-04-01

    Technical Issues Technical Report Reference: (a) N00014-91-D-0287/001 Gentlemen: The enclosed document provides an investigation into sampling intervals used...Resolution Issues Technical Report " 1 April 1992. cc: Defense Technical Information Center (2) AC, Sj. ] Naval Research Laboratory (Director) ’ • ONR...Project (AUAMP) for shallow water predictions. The Ssecond technical report to be completed under this investigation will be a compendium of shallow

  2. KSC Technical Capabilities Website

    NASA Technical Reports Server (NTRS)

    Nufer, Brian; Bursian, Henry; Brown, Laurette L.

    2010-01-01

    This document is the website pages that review the technical capabilities that the Kennedy Space Center (KSC) has for partnership opportunities. The purpose of this information is to make prospective customers aware of the capabilities and provide an opportunity to form relationships with the experts at KSC. The technical capabilities fall into these areas: (1) Ground Operations and Processing Services, (2) Design and Analysis Solutions, (3) Command and Control Systems / Services, (4) Materials and Processes, (5) Research and Technology Development and (6) Laboratories, Shops and Test Facilities.

  3. Dry pressing technical ceramics

    SciTech Connect

    Lewis, W.A. Jr.

    1996-04-01

    Dry pressing of technical ceramics is a fundamental method of producing high-quality ceramic components. The goals of dry pressing technical ceramics are uniform compact size and green density, consistent part-to-part green density and defect-free compact. Dry pressing is the axial compaction of loosely granulated dry ceramic powders (< 3% free moisture) within a die/punch arrangement. The powder, under pressure, conforms to the specific shape of the punch faces and die. Powder compaction occurs within a rigid-walled die and usually between a top and bottom punch. Press configurations include anvil, rotary, multiple-punch and multiple-action.

  4. Materials Technical Team Roadmap

    SciTech Connect

    none,

    2013-08-01

    Roadmap identifying the efforts of the Materials Technical Team (MTT) to focus primarily on reducing the mass of structural systems such as the body and chassis in light-duty vehicles (including passenger cars and light trucks) which enables improved vehicle efficiency regardless of the vehicle size or propulsion system employed.

  5. Artwork as Technics

    ERIC Educational Resources Information Center

    Jackson, Mark

    2016-01-01

    "Artwork as technics" opens discussion on activating aesthetics in educational contexts by arguing that we require some fundamental revision in understanding relations between aesthetics and technology in contexts where education is primarily encountered instrumentally and technologically. The paper addresses this through the writing of…

  6. Technical Writing in Hydrogeology.

    ERIC Educational Resources Information Center

    Tinker, John R., Jr.

    1986-01-01

    A project for Writing Across the Curriculum at the University of Wisconsin-Eau Claire is described as a method to relate the process of writing to the process of learning hydrology. The project focuses on an actual groundwater contamination case and is designed to improve the technical writing skills of students. (JN)

  7. Technical Report Bibliography.

    ERIC Educational Resources Information Center

    Hoffnagle, Gale F.

    A Bibliography of all unclassified technical reports prepared by USAF Environmental Health Laboratory, McClellan is presented. It contains a listing by subject matter and a listing of all reports by year with report number and abstract. The reports cover most areas of environmental topics such as air, water, noise, and radiation pollution. (NTIS)

  8. Artwork as Technics

    ERIC Educational Resources Information Center

    Jackson, Mark

    2016-01-01

    "Artwork as technics" opens discussion on activating aesthetics in educational contexts by arguing that we require some fundamental revision in understanding relations between aesthetics and technology in contexts where education is primarily encountered instrumentally and technologically. The paper addresses this through the writing of…

  9. PISA 2009 Technical Report

    ERIC Educational Resources Information Center

    OECD Publishing (NJ1), 2012

    2012-01-01

    The "PISA 2009 Technical Report" describes the methodology underlying the PISA 2009 survey. It examines additional features related to the implementation of the project at a level of detail that allows researchers to understand and replicate its analyses. The reader will find a wealth of information on the test and sample design,…

  10. ICCS 2009 Technical Report

    ERIC Educational Resources Information Center

    Schulz, Wolfram, Ed.; Ainley, John, Ed.; Fraillon, Julian, Ed.

    2011-01-01

    This report is structured so as to provide technical detail about each aspect of International Civic and Citizenship Education Study (ICCS). The overview is followed by a series of chapters that provide detail about different aspects of ICCS. Chapters, 2, 3, 4, and 5 are concerned with the instruments. Chapter 2 provides information about the…

  11. Education for Technical Services.

    ERIC Educational Resources Information Center

    Libbey, Maurice C., Ed.

    1985-01-01

    The 20 articles in this issue of Illinois Libraries were written by practicing technical services librarians, library educators, and former librarians now involved in commercial enterprise. The articles are: (1) "The Development of Library Education in Illinois" (Anne V. J. Wendler); (2) "Financial Management in Acquisitions: Things…

  12. Technical Evaluation Report

    DTIC Science & Technology

    2009-10-01

    NATO nations should decide, at a minimum, on bioethical boundaries before medical and materiel performance enhancement technology significantly...RTO-MP-HFM-181 T - 1 Technical Evaluation Report LTC James Ness, Ph.D. (USA) US Army Medical Research and Materiel Command Telemedicine and...Advanced Technology Research Center Medical Research and Advanced Technology Liaison Gruppe Wehrpsychologie Streitkäfteamt Bonn, Germany

  13. Final Technical Report

    SciTech Connect

    Gandy, Rex

    2000-05-15

    The technical goal of this collaborative effort is to measure electron temperature fluctuations using electron cyclotron emission on the Alcator-C tokamak. The physics goal is to understand the role that these fluctuations play in plasma transport; in particular, the influence of electron temperature fluctuations on anomalous transport. Measurement techniques and apparatus are discussed.

  14. Identifying Technical Vocabulary

    ERIC Educational Resources Information Center

    Chung, Teresa Mihwa; Nation, Paul

    2004-01-01

    This study compared four different approaches to identifying technical words in an anatomy text. The first approach used a four step rating scale, and was used as the comparison for evaluating the other three approaches. It had a high degree of reliability. The least successful approach was that using clues provided by the writer such as labels in…

  15. Technical Writing Needs Assessment.

    ERIC Educational Resources Information Center

    Oakland Community Coll., Farmington, MI. Office of Institutional Planning and Analysis.

    In fall 1991, a study was conducted by Oakland Community College (OCC) to evaluate the need for a proposed Technical Writing program. General information was gathered from a literature review, Michigan Occupational Information System data, interviews with professionals in the field, and a 1987 needs assessment conducted by Washtenaw Community…

  16. Technical Entrepreneurship: A Symposium.

    ERIC Educational Resources Information Center

    Cooper, Arnold C., Ed.; Komives, John L., Ed.

    Contained in this document are papers presented at the Symposium on Technical Entrepreneurship at Purdue University by researchers who were then or had previously been engaged in research in the area. Because formal research in this area was in its infancy, there was a particular need to afford investigators in the field opportunities to compare…

  17. PISA 2012 Technical Report

    ERIC Educational Resources Information Center

    OECD Publishing, 2014

    2014-01-01

    The "PISA 2012 Technical Report" describes the methodology underlying the PISA 2012 survey, which tested 15-year-olds' competencies in mathematics, reading and science and, in some countries, problem solving and financial literacy. It examines the design and implementation of the project at a level of detail that allows researchers to…

  18. Technical Report Bibliography.

    ERIC Educational Resources Information Center

    Hoffnagle, Gale F.

    A Bibliography of all unclassified technical reports prepared by USAF Environmental Health Laboratory, McClellan is presented. It contains a listing by subject matter and a listing of all reports by year with report number and abstract. The reports cover most areas of environmental topics such as air, water, noise, and radiation pollution. (NTIS)

  19. Grammar and Technical Writing.

    ERIC Educational Resources Information Center

    Ferguson, K. Scott; Parker, Frank

    1990-01-01

    Argues that R. A. Harris, in applying linguistic theory to technical writing, undermines his purpose by introducing irrelevant distinctions between competing syntactic theories and by failing to exploit the full potential of applications he mentions. Uses the passive construction to illustrate how linguistics can be used to advantage by technical…

  20. Teaching Technical Report Writing

    ERIC Educational Resources Information Center

    De Pasquale, Joseph A.

    1977-01-01

    A high school electronics teacher describes the integration of technical report writing in the electronics program for trade and industrial students. He notes that the report writing rather than just recording data seemed to improve student laboratory experience but further improvements in the program are needed. A sample lab report is included.…

  1. On Technical Eclecticism.

    ERIC Educational Resources Information Center

    Lazarus, Arnold A.; Beutler, Larry E.

    1993-01-01

    Underscores differences among unsystematic eclecticism, theoretical integrationism, and technical eclecticism. Present brief case history to demonstrate how and why combination of theories and smorgasbord conception of eclecticism yields clinical confusion rather than therapeutic precision. Explains why atheoretical or mechanistic procedures must…

  2. Vocational and Technical Education.

    ERIC Educational Resources Information Center

    Compact, 1968

    1968-01-01

    Volume 2, Issue 3 of "Compact" was designed to point out the problems and potential of vocational-technical education and to offer some suggestions for action. Major content includes: (1) "Education for Twenty-First Century Employment," by Wayne Morse, (2) "Pending Federal Legislation Encourages Vocational Innovation," by Grant Venn, (3)…

  3. Teaching Technical Writing.

    ERIC Educational Resources Information Center

    Lummis, Jean

    2001-01-01

    Uses concept-based laboratory reports to incorporate technical writing into teaching. Features three paragraphs in the writing format: introductory paragraph, data paragraph, and conclusion. Recommends using this teaching method, especially in chemistry laboratories, because of the difficulties students have in understanding. (YDS)

  4. Special technical assistance

    SciTech Connect

    Alexander, D.J.; Nanstad, R.K.; Sokolov, M.A.

    1995-10-01

    The purpose of this task is to perform various special analytical and experimental investigations to support the NRC in resolving regulatory research issues related to irradiation effects on materials. This task currently addresses two major areas: (1) providing technical expertise and assistance in the review of national codes and standards and (2) experimental evaluations of test specimens and practices and material properties.

  5. MCFire model technical description

    Treesearch

    David R. Conklin; James M. Lenihan; Dominique Bachelet; Ronald P. Neilson; John B. Kim

    2016-01-01

    MCFire is a computer program that simulates the occurrence and effects of wildfire on natural vegetation, as a submodel within the MC1 dynamic global vegetation model. This report is a technical description of the algorithms and parameter values used in MCFire, intended to encapsulate its design and features a higher level that is more conceptual than the level...

  6. Technical Writing in Hydrogeology.

    ERIC Educational Resources Information Center

    Tinker, John R., Jr.

    1986-01-01

    A project for Writing Across the Curriculum at the University of Wisconsin-Eau Claire is described as a method to relate the process of writing to the process of learning hydrology. The project focuses on an actual groundwater contamination case and is designed to improve the technical writing skills of students. (JN)

  7. Literature and Technical Writing.

    ERIC Educational Resources Information Center

    de Beaugrande, Robert

    By comparing the strategies involved in creating a poem and in writing a government report, this paper presents a model of reading and writing processes for exploring the relationship between literature and technical writing and for pointing out the similarities in the use of texts. The model assumes that the student approaches a piece of writing…

  8. PISA 2009 Technical Report

    ERIC Educational Resources Information Center

    OECD Publishing (NJ1), 2012

    2012-01-01

    The "PISA 2009 Technical Report" describes the methodology underlying the PISA 2009 survey. It examines additional features related to the implementation of the project at a level of detail that allows researchers to understand and replicate its analyses. The reader will find a wealth of information on the test and sample design,…

  9. PISA 2012 Technical Report

    ERIC Educational Resources Information Center

    OECD Publishing, 2014

    2014-01-01

    The "PISA 2012 Technical Report" describes the methodology underlying the PISA 2012 survey, which tested 15-year-olds' competencies in mathematics, reading and science and, in some countries, problem solving and financial literacy. It examines the design and implementation of the project at a level of detail that allows researchers to…

  10. Improved technical specifications

    SciTech Connect

    Hoffman, D.R.

    1994-12-31

    Improved technical specifications for nuclear power plants are outlined. The objectives of this work are to improve safety, provide a clearer understanding of safety significance, and ease NRC and industry administrative burdens. Line item improvements, bases, and implementation of the specifications are discussed.

  11. 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,

  12. Technical Education Now. Missouri State Plan for Postsecondary Technical Education.

    ERIC Educational Resources Information Center

    Missouri State Coordinating Board for Higher Education, Jefferson City.

    This Plan for Postsecondary Vocational Technical Education is a work in progress to build a seamless technical education delivery system from secondary through postsecondary education to employment. The plan outlines mechanisms to heighten citizen awareness of the critical importance of technical human resources to the state's economy. Similarly…

  13. 78 FR 27963 - Reliability Technical Conference; Notice of Technical Conference

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-05-13

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF ENERGY Federal Energy Regulatory Commission Reliability Technical Conference; Notice of Technical Conference Take notice that the Federal Energy Regulatory Commission will hold a Technical Conference on Tuesday, July 9,...

  14. Surface segregation of fluorinated moieties on random copolymer films controlled by random-coil conformation of polymer chains in solution.

    PubMed

    Xue, Dongwu; Wang, Xinping; Ni, Huagang; Zhang, Wei; Xue, Gi

    2009-02-17

    The relationship between solution properties, film-forming methods, and the solid surface structures of random copolymers composed of butyl methacrylate and dodecafluorheptyl methylacrylate (DFHMA) was investigated by contact angle measurements, X-ray photoelectron spectroscopy, sum frequency generation vibrational spectroscopy, and surface tension measurements. The results, based on thermodynamic considerations, demonstrated that the random copolymer chain conformation at the solution/air interface greatly affected the surface structure of the resulting film, thereby determining the surface segregation of fluorinated moieties on films obtained by various film-forming techniques. When the fluorinated monomer content of the copolymer solution was low, entropic forces dominated the interfacial structure, with the perfluoroalkyl groups unable to migrate to the solution/air interface and thus becoming buried in a random-coil chain conformation. When employing this copolymer solution for film preparation by spin-coating, the copolymer chains in solution were likely extended due to centrifugal forces, thereby weakening the entropy effect of the polymer chains. Consequently, this resulted in the segregation of the fluorinated moieties on the film surface. For the films prepared by casting, the perfluoroalkyl groups were, similar to those in solution, incapable of segregating at the film surface and were thus buried in the random-coil chains. When the copolymers contained a high content of DFHMA, the migration of perfluoroalkyl groups at the solution/air interface was controlled by enthalpic forces, and the perfluoroalkyl groups segregated at the surface of the film regardless of the film-forming technique. The aim of the present work was to obtain an enhanced understanding of the formation mechanism of the chemical structure on the surface of the polymer film, while demonstrating that film-forming methods may be used in practice to promote the segregation of fluorinated

  15. Synthesis and evaluation of antioxidant and cytotoxicity of the N-Mannich base of berberine bearing benzothiazole moieties.

    PubMed

    Mistry, Bhupendra M; Keum, Young-Soo; Pandurangan, Muthuraman; Kim, Doo Hwan; Moon, So Hyun; Kadam, Avinash A; Shinde, Surendra; Shin, Han-Seung; Patel, Rahul V

    2017-07-10

    The N-Mannich base of an isoquinoline alkaloid, berberine, bearing substituted benzothiazole moieties was obtained. Novel synthesized analogues were in vitro screened for antioxidant efficacy toward 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) free radicals and in vitro cytotoxicity towards cervical cancer cell lines (HeLa and CaSki), an ovarian cancer cell line (SK-OV-3) and human renal cancer cell line (Caki-2). Cytotoxicity of the compounds toward normal cell lines was examined using the Madin-Darby canine kidney (MDCK) non-cancer cell line. Analogues bearing a methoxy functional group (5e), acid functionality (5c), and a cyano group (5m) showed remarkable radical scavenging potential in DPPH and ABTS bioassays. Potent cytotoxicity exhibited by berberine against the HeLa cell line was attributable to the presence of a 2-aminobenzothaizole moiety (5a) and its 6-chloro congener (5g) on the berberine core, and the 6-cyano group (5m) on the benzothiazole ring revealed strong sensitivity for the CaSki cell line, whereas subjected scaffolds demonstrated diminished activity against the SK-OV-3 cell line. In addition, the compound with a 2-aminobenzothaizole moiety (5a), compound with methoxy functional group (5e) and compound with cyano group appeared with the most significant cytotoxicity effect in Caki-2 cell line. Their structures have been elucidated by FT-IR, 1H NMR, 13C NMR, and elemental analyses (CHN) essential research. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  16. Functionalized mesoporous silicas with crown ether moieties for selective adsorption of lithium ions in artificial sea water.

    PubMed

    Sung, Soo Park; Moorthy, Madhappan Santha; Song, Hyun-Jin; Ha, Chang-Sik

    2014-11-01

    Lithium ion has been increasingly recognized in a wide range of industrial applications. In this work, we studied on the adsorption of Li+ in the artificial seawater with high selectivity using methyl-crown ether (AC-SBA-15) and aza-crown ether (HMC-SBA-15) moieties-functionalized mesoporous silica materials. First, methyl-crown ether and aza-crown ether moieties-functionalized mesoporous silica materials were synthesized via two-step post-synthesis process using a grafting method. The functionalized materials were employed to the metal ion adsorption from aqueous solution (artificial seawater) containing Li+, Co2+, Cr3+ and Hg2+. The prepared hybrid material showed high selectivity for Li+ ion in the artificial seawater at pH 8.0. The absorbed amount of Li+ was 73 times higher than Cr3+ for aza-crown ether containing AC-SBA-15 as an absorbent. The absorbed amount of Co2+ (4.5 x 10(-5) mol/g), Cr3+ (1.5 x 10(-5) mol/g) and Hg2+ (2.25 x 10(-4) mol/g) were remarkably lower than the case of Li+. On the other hand, the absorbed amount of various metal ions of HMC-SBA-15 with amine groups in alky chains and crown ether moieties were 1.1 x 10(-3) mol/g for Li+, 5.0 x 10(-5) mol/g for Co2+, 2.9 x 10(-4) mol/g for Cr3+, 2.8 x 10(-4) mol/g for Hg2+ mol/g, respectively.

  17. Design, synthesis and docking studies of novel thienopyrimidine derivatives bearing chromone moiety as mTOR/PI3Kα inhibitors.

    PubMed

    Zhu, Wufu; Chen, Chen; Sun, Chengyu; Xu, Shan; Wu, Chunjiang; Lei, Fei; Xia, Hui; Tu, Qidong; Zheng, Pengwu

    2015-03-26

    Two series of thienopyrimidine derivatives (10a-k, 16a-j) bearing chromone moiety were designed and synthesized. All the compounds were evaluated for inhibitory activity against mTOR kinase at a concentration of 10uM. Four selected compounds were further evaluated for the IC50 values against mTOR kinase, PI3Kα kinase and two cancer cell lines. Some of the target compounds exhibited moderate to excellent mTOR/PI3Kα kinase inhibitory activity and cytotoxicity. The most promising compound 16i showed good inhibitory activity against mTOR/PI3Kα kinase and good antitumor potency for H460 and PC-3 cell lines with IC50 values of 0.16 ± 0.03 μM, 2.35 ± 0.19 μM, 1.20 ± 0.23 μM and 0.85 ± 0.04 μM, which were 8.6, >5, 7.9 and 19.1 times more active than compound I (1.37 ± 0.07 μM, >10 μM, 9.52 ± 0.29 μM, 16.27 ± 0.54 μM), respectively. Structure-activity relationships (SARs) and docking studies indicated that the chromone moiety is necessary for the potent antitumor activity and cytotoxicity of these compounds. Substitution of the chromone moiety at the 6-position has a significant impact to the inhibitory activity, in particular a carboxylic acid group, produced the best potency. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

  18. Lanthanide coordination polymers based on multi-donor ligand containing pyridine and phthalate moieties: Structures, luminescence and magnetic properties

    SciTech Connect

    Feng, Xun; Liu, Lang; Wang, Li-Ya; Song, Hong-Liang; Qiang Shi, Zhi; Wu, Xu-Hong; Ng, Seik-Weng

    2013-10-15

    A new family of five lanthanide-organic coordination polymers incorporating multi-functional N-hetrocyclic dicarboxylate ligand, namely, [Ln{sub 2}(Hdpp){sub 2}(dpp){sub 2}]{sub n}Ln=Pr(1), Eu(2), Gd(3), Dy(4), Er(5) (H{sub 2}dpp=1-(3, 4-dicarboxyphenyl) pyridin-4-ol) have been fabricated successfully through solvothermal reaction of 1-(3,4-dicarboxyphenyl)-4-hydroxypyridin-1-ium chloride with trivalent lanthanide salts, and have been characterized systematically. The complexes 1–5 are isomorphous and isostructural. They all feature three dimensional (3D) frameworks based on the interconnection of 1D double chains composed of the binuclear moiety [Ln{sub 2}(Hdpp){sub 2}]{sup 4+} basic carboxylate as secondary building unit (SBU). The results of magnetic analysis shows the same bridging fashion of carboxylic group in this case results in the different magnetic properties occurring within lanthanide polymers. Moreover, the Eu(III) and Dy(III) complexes display characteristic luminescence emission in the visible regions. - Graphical abstract: A new family of lanthanide-organic frameworks incorporating multi-donor twisted ligand has been fabricated successfully, and has been characterized systematically. The complexes 1–5 are isostructural, and all feather three dimensional (3D) frameworks based on the interconnection of 1D double stride chains composed of the binuclear moiety [Ln{sub 2}(Hdpp){sub 2}]{sup 2+} basic carboxylate as secondary building unit (SBU). Display Omitted - Highlights: • New family of lanthanide–organic coordination polymers incorporating multifunctional N-hetrocyclic dicarboxylate ligand has been fabricated. • They have been characterized systematically. • They all feather three dimensional frameworks based on the binuclear moiety of [Ln{sub 2}(Hdpp){sub 2}]{sup 2+}. • The Eu(III) and Dy(III) analogues exhibit intense photoluminescence.

  19. Interpersonal Skills for Technical Writers.

    ERIC Educational Resources Information Center

    Fridie, Pamela

    1986-01-01

    Describes a summer internship as a faculty technical writer with a business corporation, revising installation manuals based upon information from computer programers--an experience that highlighted technical writers' need for interpersonal skills. (HTH)

  20. Technical Assistance Needs Assessments (TANAs)

    EPA Pesticide Factsheets

    The Technical Assistance Needs Assessment (TANA) is a process to identify whether a community requires additional support from EPA in order to understand technical information and have meaningful participation in the Superfund decision-making process.

  1. Upgrading the Beginning Technical Student

    ERIC Educational Resources Information Center

    Boudreau, Howard E.

    1971-01-01

    How a pre-technical program, established to maintain the high engineering technology program standards, succeeds while maintaining an open door" policy. Technical Education is a bimonthly supplement to Industrial Arts and Vocational Education. (GB)

  2. Introducing Invention to Technical Students

    ERIC Educational Resources Information Center

    Allen, J. W., Jr.

    1978-01-01

    Outlines approaches for defining and presenting invention techniques to technical writing students; describes the method used by a technical writing teacher to demonstrate the usefulness of such techniques. (GW)

  3. The Genre of Technical Description.

    ERIC Educational Resources Information Center

    Jordan, Michael P.

    1986-01-01

    Summarizes recent research into systems of lexical and grammatical cohesion in technical description. Discusses various methods by which technical writers "re-enter" the topic of description back into the text in successive sentences. (HTH)

  4. Assignment of the absolute configuration of P-chiral 5' mRNA cap analogues containing phosphorothioate moiety.

    PubMed

    Kowalska, Joanna; Lewdorowicz, Magdalena; Zuberek, Joanna; Bojarska, Elzbieta; Stepinski, Janusz; Stolarski, Ryszard; Darzynkiewicz, Edward; Jemielity, Jacek

    2007-01-01

    Enzymatic cleavage of the P-chiral diastereoisomers of the 5' mRNA cap analogue bearing phosphorothioate moiety in alfa position of 5',5'-triphosphate bridge (m(7)Gppp(S)G D1 and D2) was performed by human Decapping Scavenger (DcpS) enzyme. Analysis of the degradation products allowed to estimate the absolute configuration at the asymmetric phosphorus atoms in examined compounds via correlation with the R(P) and S(P) diastereoisomers of guanosine 5'-O-(1-thiodiphosphate) (GDPalphaS).

  5. The design and synthesis of novel SGLT2 inhibitors: C-glycosides with benzyltriazolopyridinone and phenylhydantoin as the aglycone moieties.

    PubMed

    Guo, Cheng; Hu, Min; DeOrazio, Russell J; Usyatinsky, Alexander; Fitzpatrick, Kevin; Zhang, Zhenjun; Maeng, Jun-Ho; Kitchen, Douglas B; Tom, Susan; Luche, Michele; Khmelnitsky, Yuri; Mhyre, Andrew J; Guzzo, Peter R; Liu, Shuang

    2014-07-01

    The sodium glucose co-transporter 2 (SGLT2) has received considerable attention in recent years as a target for the treatment of type 2 diabetes mellitus. This report describes the design, synthesis and structure-activity relationship (SAR) of C-glycosides with benzyltriazolopyridinone and phenylhydantoin as the aglycone moieties as novel SGLT2 inhibitors. Compounds 5p and 33b demonstrated high potency in inhibiting SGLT2 and high selectivity against SGLT1. The in vitro ADMET properties of these compounds will also be discussed.

  6. A new bioassay for the immunocytokine L19-IL2 for simultaneous analysis of both functional moieties.

    PubMed

    Winter, Jonas; Barbin, Karin; Bacci, Camilla; Bunte, Thomas

    2011-01-05

    Currently, cancer directed new biological entities (NBEs) in the pharmaceutical R&D pipelines are derived from monoclonal antibodies in various formats, such as immunocytokines. Generally, immunocytokines are bi-functional molecules that consist of a specific targeting antibody-based portion and a linked cytokine. To confirm the quality of the drug product both moieties have to be characterized using appropriate techniques. Until now, the binding capacity of antibodies is usually examined by ligand binding assays whereas the biological activity of the linked cytokine is determined by cell-based potency assays. However, the simultaneous analysis of both functional moieties in a single assay format has not been described so far. In this paper we present a newly designed bioassay format for the anti-cancer immunocytokine L19-IL2, comprising of the human vascular targeting single-chain Fv L19 and human interleukin 2 (IL2). This new potency assay allows simultaneous analysis of both moieties, thus specific L19 binding capacity and the ability of IL2 to induce the proliferation of the detector cytotoxic T-cell line CTLL-2. Assay development was performed with special focus on application of different fitting models for the sigmoid dose-response curves to evaluate the influence of model optimization on the validity of assay results. For assay validation generally accepted characteristics were determined. Assay specificity was shown by testing L19-IL2 related compounds. All other validation parameters were derived from 25 batch runs using five nominal L19-IL2 concentrations, covering a range from 60% to 140% of the standard's potency. Accuracy ranged from -3.4% to -6.9% relative error (%RE). Interbatch precision ranged from 6.1% to 10.6% coefficient of variation (%CV). For assay linearity a coefficient of determination (R(2)) of 0.9992 was found. Assay robustness was shown with L19-IL2 samples after three freeze-thaw cycles and also with different cell passages of the used

  7. One-pot synthesis and antifungal activity against plant pathogens of quinazolinone derivatives containing an amide moiety.

    PubMed

    Zhang, Jin; Liu, Jia; Ma, Yangmin; Ren, Decheng; Cheng, Pei; Zhao, Jiawen; Zhang, Fan; Yao, Yuan

    2016-05-01

    An efficient one-pot, three-component synthesis of quinazolinone derivatives containing 3-acrylamino motif was carried out using CeO2 nanoparticles as catalyst. Thirty-nine synthesized compounds were obtained with satisfied yield and elucidated by spectroscopic analysis. Four phytopathogenic fungi were chosen to test the antifungal activities by minimum inhibitory concentration (MIC) method. Compounds 4ag, 4bb, 4bc showed broad antifungal activities against at least three fungi, and dramatic effects of substituents on the activities were observed. Docking studies were established to explore the potential antifungal mechanism of quinazolinone derivatives as the chitinase inhibitors, and also verified the importance of the amide moiety.

  8. Technical Typography Using Personal Computers

    DTIC Science & Technology

    1989-07-01

    LETTER REPORT 359 00 TECHNICAL TYPOGRAPHY USING PERSONAL COMPUTERS i James M. King DTIC ELECTE fliN AUG 1 6 1989 D D o. U July 1989 Aroved for public...endorsement of any of the products or companies mentioned. The opinions expressed herein are solely those of the author. ABSTRACT Technical typography is...tefrursivvd in publishing technical manuscripts, who require th highest quality of technical typography . General users willing to expend the necessary time and

  9. Self-assembled mesoscopic surface domains of fluorocarbon-hydrocarbon diblocks can form at zero surface pressure: tilting of solid-like hydrocarbon moieties compensates for cross-section mismatch with fluorocarbon moieties.

    PubMed

    Schwieger, Christian; Liu, Xianhe; Krafft, Marie Pierre

    2017-09-13

    At low molecular areas, fluorocarbon-hydrocarbon diblocks (CnF2n+1CmH2m+1, FnHm), when spread as Langmuir monolayers on water, form organized monodisperse circular self-assembled domains, one molecule high and tens of nanometers in diameter. Whether such domains form at high molecular areas (low surface pressures) could until now not be established. Furthermore, the common assumption was that the inner core hydrocarbon chains within these domains were in the liquid state in order to compensate for the difference in the cross-section area between the perfluoroalkyl (∼30 Å(2)) and alkyl (∼20 Å(2)) chains. Our IRRAS investigation of F8H16 now establishes (1) that these diblock surface domains do exist at the air/water interface at large molecular areas (zero surface pressure), (2) that they remain essentially unchanged throughout film compression, and (3) that the H16 moieties are actually stretched in an all-trans configuration and tilted by ∼30° with respect to the normal to the monolayer in order to satisfy the greater space requirement of the F8 moieties. Consequently, the core of the domains is in an ordered, crystalline-like state, and the domains can be visualized as solid particles at the air/water interface.

  10. Independent technical review, handbook

    SciTech Connect

    Not Available

    1994-02-01

    Purpose Provide an independent engineering review of the major projects being funded by the Department of Energy, Office of Environmental Restoration and Waste Management. The independent engineering review will address questions of whether the engineering practice is sufficiently developed to a point where a major project can be executed without significant technical problems. The independent review will focus on questions related to: (1) Adequacy of development of the technical base of understanding; (2) Status of development and availability of technology among the various alternatives; (3) Status and availability of the industrial infrastructure to support project design, equipment fabrication, facility construction, and process and program/project operation; (4) Adequacy of the design effort to provide a sound foundation to support execution of project; (5) Ability of the organization to fully integrate the system, and direct, manage, and control the execution of a complex major project.

  11. ION-1 technical manual

    SciTech Connect

    Halbig, J.K.; Caine, J.C.

    1985-07-01

    The portable gamma-ray and neutron detector electronics (ION-1) gives a digital readout of the current-mode response produced by gamma rays in an ion chamber and of amplification and scaling of pulses received from a neutron detector. The primary application is the measurement of gamma-ray and neutron activity of irradiated reactor fuels stored at a reactor or at a storage pond away from a reactor. ION-1 is the first such instrument to use a design that allows communication of procedures, response, and results between instrument and inspector. It prompts the inspector through procedures, carries out programmed measurement steps, calculates results and error estimates, and performs internal diagnostic checks. This Technical Manual describes adjustment procedures and limited technical information that enable the inspector to troubleshoot at the board level. 5 figs., 10 tabs.

  12. Bioethics for Technical Experts

    NASA Astrophysics Data System (ADS)

    Asano, Shigetaka

    Along with rapidly expanding applications of life science and technology, technical experts have been implicated more and more often with ethical, social, and legal problems than before. It should be noted that in this background there are scientific and social uncertainty elements which are inevitable during the progress of life science in addition to the historically-established social unreliability to scientists and engineers. In order to solve these problems, therefore, we should establish the social governance with ‘relief’ and ‘reliance’ which enables for both citizens and engineers to share the awareness of the issues, to design social orders and criterions based on hypothetical sense of values for bioethics, to carry out practical use management of each subject carefully, and to improve the sense of values from hypothetical to universal. Concerning these measures, the technical experts can learn many things from the present performance in the medical field.

  13. Final Technical Report

    SciTech Connect

    Maxwell, Mike, J., P.E.

    2012-08-30

    The STI product is the Final Technical Report from ReliOn, Inc. for contract award DE-EE0000487: Recovery Act PEM Fuel Cell Systems Providing Emergency Reserve and Backup Power. The program covered the turnkey deployment of 431 ReliOn fuel cell systems at 189 individual sites for AT&T and PG&E with ReliOn functioning as the primary equipment supplier and the project manager. The Final Technical Report provides an executive level summary, a comparison of the actual accomplishments vs. the goals and objectives of the project, as well as a summary of the project activity from the contract award date of August 1, 2009 through the contract expiration date of December 31, 2011. Two photos are included in the body of the report which show hydrogen storage and bulk hydrogen refueling technologies developed as a result of this program.

  14. Microemulsions in technical processes

    SciTech Connect

    Schwuger, M.J.; Stickdorn, K.; Schomaecker, R.

    1995-06-01

    The aim of this review is to present once again the basic properties of microemulsions and to relate them to some already established applications and also to show further potential fields of application. This review will survey this area, focusing mainly on the last decade. Earlier publications on the technical relevance of microemulsions and reverse micelles were reviewed by Langevin in 1982. The most important properties of these systems, which are of significance for technical applications, will be described. The applications discussed are: enhanced oil recovery; liquid-liquid extraction; extraction from chemically contaminated soils; lubricants and cutting oils; pharmaceuticals and cosmetics; washing; impregnation and textile finishing; and chemical reactions in microemulsions. 143 refs.

  15. [Standardization of technical terminology].

    PubMed

    Wesolowski, Tilmann

    2010-01-01

    This paper analyzes the example of the publishers Oldenbourg and the publication of the 'Illustrierte Technische Wörterbücher' (ITW), a multilingual dictionary which competed with a similar project that the Verein Deutscher Ingenieure (VDI) had already initiated. Its willingness to challenge the vast and well-funded VDI with this project--and to tackle the immense difficulties associated with the dictionary itself, which pioneered the standardization of technical terminology across six languages--indicates that for Oldenbourg, this project was of paramount importance to its reputation. The decision to take the challenge and publish the ITW was the starting point of Alfred Schlomann's career as well as the foundation of Oldenbourgs reputation as a premier publishing house and pioneered the standardization of technical terminology. The example shows that the publishers' decisions had been of paramount importance not only for scientists' careers and as gatekeeper of the scientific community but can also influence the development of science.

  16. SPS technical issues

    NASA Technical Reports Server (NTRS)

    Guttman, C. H.

    1980-01-01

    The technical issues which would either seriously impact or potentially negate the integrity of a solar power satellite program are enumerated. Issues are identified not only relating to the question of engineering feasibility, but also to the equally important areas of environmental and social acceptability and, especially, economic viability. Specific information required for resolution of the issues was developed and a planned overall approach for resolution was identified. Results of these analyses show that 60% of the technical issues can be resolved with analysis only; 10% require only ground testing for resolution; and the remaining 30% require space experiments or demonstrations for resolution. The results also show that 85% resolution of the issues may be accomplished prior to development of a protoype.

  17. Assessing Students' Technical Skill Attainment

    ERIC Educational Resources Information Center

    Jorgensen, Haley

    2010-01-01

    The Wisconsin Technical College System (WTCS) is working to comply with the Carl D. Perkins Career and Technical Education Improvement Act of 2006 (Perkins) to ensure that its graduates have mastered the technical skills needed by business and industry. The legislation requires that each state identify and approve program assessment strategies…

  18. Advisory Technical Skills Committee Manual

    ERIC Educational Resources Information Center

    Barbee, Jim R.

    2005-01-01

    The use of advisory committees is well established in the public school system. The purpose of advisory committees is to provide leadership, guidance and technical assistance to maintain, improve and develop quality career and technical education programs. This manual is written for those planning to form new advisory technical skills committees,…

  19. Technical approach document

    SciTech Connect

    Not Available

    1989-12-01

    The Uranium Mill Tailings Radiation Control Act (UMTRCA) of 1978, Public Law 95-604 (PL95-604), grants the Secretary of Energy the authority and responsibility to perform such actions as are necessary to minimize radiation health hazards and other environmental hazards caused by inactive uranium mill sites. This Technical Approach Document (TAD) describes the general technical approaches and design criteria adopted by the US Department of Energy (DOE) in order to implement remedial action plans (RAPS) and final designs that comply with EPA standards. It does not address the technical approaches necessary for aquifer restoration at processing sites; a guidance document, currently in preparation, will describe aquifer restoration concerns and technical protocols. This document is a second revision to the original document issued in May 1986; the revision has been made in response to changes to the groundwater standards of 40 CFR 192, Subparts A--C, proposed by EPA as draft standards. New sections were added to define the design approaches and designs necessary to comply with the groundwater standards. These new sections are in addition to changes made throughout the document to reflect current procedures, especially in cover design, water resources protection, and alternate site selection; only minor revisions were made to some of the sections. Sections 3.0 is a new section defining the approach taken in the design of disposal cells; Section 4.0 has been revised to include design of vegetated covers; Section 8.0 discusses design approaches necessary for compliance with the groundwater standards; and Section 9.0 is a new section dealing with nonradiological hazardous constituents. 203 refs., 18 figs., 26 tabs.

  20. DENSO Technical Communication Education

    NASA Astrophysics Data System (ADS)

    Isogai, Emiko; Suzuki, Takamasa

    We developed technical communication education from beginning to managerial levels to enhance communication skills necessary for engineers. The courses in this program progressed from theory to hands-on training and discussion, providing an opportunity for fact-finding and problem-solving. After the courses were completed, the engineers applied what they had learned on the job. The courses proved to be useful, satisfying participating engineers.

  1. Superfund Technical Assistance Grants

    EPA Pesticide Factsheets

    This asset includes data related to the Superfund Technical Assistance Grant program, including grant number, award amounts, award dates, period of performance, site/PRP name, and community group awarded grant. Data collected from Regional TAG Coordinators enables HQ to easily access statistical information on the TAG program in order to respond to requests for Catalog of Federal Domestic Assistance (CFDA) updates, requests for talking point information, questions from OSRTI/OSWER managers, and other various requests for program statistics.

  2. Technical computing system evaluations

    SciTech Connect

    Shaw, B.R.

    1987-05-01

    The acquisition of technical computing hardware and software is an extremely personal process. Although most commercial system configurations have one of several general organizations, individual requirements of the purchaser can have a large impact on successful implementation even though differences between products may seem small. To assure adequate evaluation and appropriate system selection, it is absolutely essential to establish written goals, create a real benchmark data set and testing procedure, and finally test and evaluate the system using the purchaser's technical staff, not the vendor's. BHP P(A) (formerly Monsanto Oil Company) was given the opportunity to acquire a technical computing system that would meet the needs of the geoscience community, provide future growth avenues, and maintain corporate hardware and software standards of stability and reliability. The system acquisition team consisted of a staff geologist, geophysicist, and manager of information systems. The eight-month evaluation allowed the development procedures to personalize and evaluate BHP needs as well as the vendor's products. The goal-driven benchmark process has become the standard procedure for system additions and expansions as well as product acceptance evaluations.

  3. 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.

  4. Chemoprevention of oxidative stress-associated oral carcinogenesis by sulforaphane depends on NRF2 and the isothiocyanate moiety.

    PubMed

    Lan, Aixian; Li, Wenjun; Liu, Yao; Xiong, Zhaohui; Zhang, Xinyan; Zhou, Shanshan; Palko, Olesya; Chen, Hao; Kapita, Mayanga; Prigge, Justin R; Schmidt, Edward E; Chen, Xin; Sun, Zheng; Chen, Xiaoxin Luke

    2016-08-16

    Oxidative stress is known to play an important role in oral cancer development. In this study we aimed to examine whether a chemical activator of NRF2, sulforaphane (SFN), may have chemopreventive effects on oxidative stress-associated oral carcinogenesis. We first showed that Nrf2 activation and oxidative damage were commonly seen in human samples of oral leukoplakia. With gene microarray and immunostaining, we found 4-nitroquinoline 1-oxide (4NQO) in drink activated the Nrf2 pathway and produced oxidative damage in mouse tongue. Meanwhile whole exome sequencing of mouse tongue identified mutations consistent with 4NQO's mutagenic profile. Using cultured human oral keratinocytes and 4NQO-treated mouse tongue, we found that SFN pre-treatment activated the NRF2 pathway and inhibited oxidative damage both in vitro and in vivo. On the contrary, a structural analogue of SFN without the isothiocyanate moiety did not have such effects. In a long-term chemoprevention study using wild-type and Nrf2-/- mice, we showed that topical application of SFN activated the NRF2 pathway, inhibited oxidative damage, and prevented 4NQO-induced oral carcinogenesis in an Nrf2-dependent manner. Our data clearly demonstrate that SFN has chemopreventive effects on oxidative stress-associated oral carcinogenesis, and such effects depend on Nrf2 and the isothiocyanate moiety.

  5. 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.

  6. A highly selective fluorescence-based polymer sensor incorporating an (R,R)-salen moiety for Zn(2+) detection.

    PubMed

    Xu, Ying; Meng, Jie; Meng, Lingxing; Dong, Yu; Cheng, Yixiang; Zhu, Chengjian

    2010-11-15

    A chiral polymer incorporating an (R,R)-salen moiety was synthesized by the polymerization of (R,R)-1,2-diaminocyclohexane with 2,5-dibutoxy-1,4-di(salicyclaldehyde)-1,4-diethynyl-benzene by a nucleophilic addition-elimination reaction. The fluorescence responses of the (R,R)-salen-based polymer toward various metal ions were investigated by fluorescence spectra. Compared with other cations, such as Na(+), K(+), Mg(2+), Ca(2+), Mn(2+), Fe(2+), Fe(3+), Co(2+), Ni(2+), Cu(2+), Ag(+), Cd(2+), Hg(2+), and Pb(2+), Zn(2+) can lead to a pronounced fluorescence enhancement as high as 7.8-fold together with an obvious blue-shift change of the chiral polymer. More importantly, the fluorescent color of the polymer changed to bright blue instead of weak yellow after addition of Zn(2+), which can be easily detected by the naked eye. The results indicate that this kind of chiral polymer, incorporating an (R,R)-salen moiety as a receptor in the main chain backbone, can exhibit high sensitivity and selectivity for Zn(2+) recognition.

  7. Charge carrier transport properties in polymer liquid crystals containing oxadiazole and amine moieties in the same side chain.

    PubMed

    Kawamoto, Masuki; Mochizuki, Hiroyuki; Ikeda, Tomiki; Iino, Hiroaki; Hanna, Jun-ichi

    2005-05-19

    Steady-state and transient photocurrent measurements were carried out to study the charge carrier transport properties of polymer liquid crystal (LC) containing oxadiazole (OXD) and amine moieties in the same side chain. The steady-state photocurrent measurement with asymmetric electrodes of ITO and Al and a short penetration depth of the illumination light indicated that both electrons and holes can be transported in this film. The transient hole photocurrent observed by time-of-flight (TOF) experiments was dispersive at room temperature. The hole drift mobility significantly depended on temperature and electric field and was determined to be 6.1 x 10(-8) cm2/Vs at a field of 9.1 x 10(5) V/cm. According to the disorder formalism, the Gaussian width of the density of states was determined to be 170 meV for holes. Despite the indication of possible electron transport in this film, we could not determine the electron mobility by TOF experiments due to strong dispersive photocurrent. We discuss the present charge transport properties of the film in relation to a large dipole attributed to an electrical push-pull structure of p-dimethylaminophenyl-substitited OXD moiety in polymer LC and its electroluminescent properties.

  8. Biosynthesis of triacylglycerols containing very long chain monounsaturated acyl moieties in developing seeds. [Lunaria annua L. ; Sinapis alba L

    SciTech Connect

    Fehling, E.; Murphy, D.J.; Mukherjee, K.D. )

    1990-10-01

    Particulate (15,000g) fractions from developing seeds of honesty (Lunaria annua L.) and mustard (Sinapis alba L.) synthesize radioactive very long chain monounsaturated fatty acids (gadoleic, erucic, and nervonic) from (1-{sup 14}C)oleoyl-CoA and malonyl-CoA or from oleoyl-CoA and (2-{sup 14}C)malonyl-CoA. The very long chain monounsaturated fatty acids are rapidly channeled to triacylglycerols and other acyl lipids without intermediate accumulation of their CoA thioesters. When (1-{sup 14}C)oleoyl-CoA is used as the radioactive substrate, phosphatidylcholines and other phospholipids are most extensively radiolabeled by oleoyl moieties rather than by very long chain monounsaturated acyl moieties. When (2-{sup 14}C)malonyl-CoA is used as the radioactive substrate, no radioactive oleic acid is formed and the newly synthesized very long chain monounsaturated fatty acids are extensively incorporated into phosphatidylcholines and other phospholipids as well as triacylglycerols. The pattern of labeling of the key intermediates of the Kennedy pathway, e.g. lysophosphatidic acids, phosphatidic acids, and diacylglycerols by the newly synthesized very long chain monounsaturated fatty acids is consistent with the operation of this pathway in the biosynthesis of triacylglycerols.

  9. In Situ Surface Tailoring with Zwitterionic Carboxybetaine Moieties on Self-Assembled Thin Film for Antifouling Biointerfaces

    PubMed Central

    Huang, Chun-Jen; Chang, Ying-Chih

    2014-01-01

    A novel biointerface bearing zwitterionic carboxybetaine moieties was developed for effective resistance to nonspecific adsorption of proteins and blood cells. Self-assembled thin films (SAFs) of (N,N-dimethylaminopropyl) trimethoxysilane were formed as mattress layers by either vapor or solution deposition. Subsequently, the tertiary amine head groups on SAFs were reacted with β-propiolactone to give zwitterionic carboxybetaine moieties via in situ synthesis. The optimal reaction time of 8 h for both preparation methods was verified by static contact angle measurements. According to the X-ray photoelectron spectroscopy, 67.3% of amine groups on SAFs prepared from the vapor deposition was converted to the zwitterionic structures after reaction of β-propiolactone. The antifouling properties of the zwitterionic biointerfaces were quantitatively evaluated in the presence of protein solutions using a quartz crystal microbalance with dissipation, showing a great improvement by factors of 6.5 and 20.2 from tertiary amine SAFs and bare SiO2 surfaces, respectively. More importantly, the zwitterionic SAFs were brought to contact with undiluted human blood in chaotic-mixer microfluidic systems; the results present their capability to effectively repel blood cell adhesion. Accordingly, in this work, development of carboxybetaine SAFs offers a facile yet effective strategy to fabricate biocompatible biointerfaces for a variety of potential applications in surface coatings for medical devices. PMID:28788445

  10. Stevia Glycosides: Chemical and Enzymatic Modifications of Their Carbohydrate Moieties to Improve the Sweet-Tasting Quality.

    PubMed

    Gerwig, Gerrit J; Te Poele, Evelien M; Dijkhuizen, Lubbert; Kamerling, Johannis P

    2016-01-01

    Stevia glycosides, extracted from the leaves of the plant Stevia rebaudiana Bertoni, display an amazing high degree of sweetness. As processed plant products, they are considered as excellent bio-alternatives for sucrose and artificial sweeteners. Being noncaloric and having beneficial properties for human health, they are the subject of an increasing number of studies for applications in food and pharmacy. However, one of the main obstacles for the successful commercialization of Stevia sweeteners, especially in food, is their slight bitter aftertaste and astringency. These undesirable properties may be reduced or eliminated by modifying the carbohydrate moieties of the steviol glycosides. A promising procedure is to subject steviol glycosides to enzymatic glycosylation, thereby introducing additional monosaccharide residues into the molecules. Depending on the number and positions of the monosaccharide units, the taste quality and sweetness potency of the compounds will vary. Many studies have been performed already, and this review summarizes the structures of native steviol glycosides and the recent data of modifications of the carbohydrate moieties that have been published to provide an overview of the current progress.

  11. Role of the sugar moiety on the opioid receptor binding and conformation of a series of enkephalin neoglycopeptides.

    PubMed

    Rosa, Mònica; Gonzalez-Nunez, Verónica; Barreto-Valer, Katherine; Marcelo, Filipa; Sánchez-Sánchez, Julia; Calle, Luis P; Arévalo, Juan C; Rodríguez, Raquel E; Jiménez-Barbero, Jesús; Arsequell, Gemma; Valencia, Gregorio

    2017-04-01

    Glycosylation by simple sugars is a drug discovery alternative that has been explored with varying success for enhancing the potency and bioavailability of opioid peptides. Long ago we described two O-glycosides having either β-Glucose and β-Galactose of (d-Met(2), Pro(5))-enkephalinamide showing one of the highest antinociceptive activities known. Here, we report the resynthesis of these two analogs and the preparation of three novel neoglycopeptide derivatives (α-Mannose, β-Lactose and β-Cellobiose). Binding studies to cloned zebrafish opioid receptors showed very small differences of affinity between the parent compound and the five glycopeptides thus suggesting that the nature of the carbohydrate moiety plays a minor role in determining the binding mode. Indeed, NMR conformational studies, combined with molecular mechanics calculations, indicated that all glycopeptides present the same major conformation either in solution or membrane-like environment. The evidences provided here highlight the relevance for in vivo activity of the conjugating bond between the peptide and sugar moieties in opioid glycopeptides. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. A conserved flagellar pocket exposed high mannose moiety is used by African trypanosomes as a host cytokine binding molecule.

    PubMed

    Magez, S; Radwanska, M; Stijlemans, B; Xong, H V; Pays, E; De Baetselier, P

    2001-09-07

    Trypanosomes use antigenic variation of their variant-specific surface glycoprotein (VSG) coat as defense against the host immune system. However, in order to sustain their growth, they need to expose conserved epitopes, allowing host macromolecule binding and receptor-mediated endocytosis. Here we show that Trypanosoma brucei uses the conserved chitobiose-oligomannose (GlcNAc(2)-Man(5-9)) moieties of its VSG as a binding ligand for tumor necrosis factor (TNF), a host cytokine with lectin-like properties. As endocytosis in trypanosomes is restricted to the flagellar pocket, we show that soluble flagellar pocket extracts, and in particular soluble VSG, inhibit the binding of (125)I-TNF to trypanosomes. The interaction between TNF and VSG is confirmed by affinity chromatography, biosensor, and dot-blot affinity measurements, and soluble VSG inhibition of TNF-mediated trypanolysis. In all approaches, removal of N-linked carbohydrates abrogates the TNF-VSG interaction. In addition, synthetic high mannose oligosaccharides can block TNF-VSG interactions, and a VSG glycopeptide carrying the GlcNAc(2)-Man(5-9) moiety is shown to inhibit TNF-mediated trypanosome killing in mixed parasite/macrophage cell cultures. Together, these results support the observation that TNF plays a role in growth control of trypanosomes and, moreover, suggest that, by the use of conserved VSG carbohydrates as lectin-binding epitopes, trypanosomes can limit the necessity to express large numbers of invariant surface exposed receptors.

  13. Chemoprevention of oxidative stress-associated oral carcinogenesis by sulforaphane depends on NRF2 and the isothiocyanate moiety

    PubMed Central

    Liu, Yao; Xiong, Zhaohui; Zhang, Xinyan; Zhou, Shanshan; Palko, Olesya; Chen, Hao; Kapita, Mayanga; Prigge, Justin R.; Schmidt, Edward E.; Chen, Xin; Sun, Zheng; Chen, Xiaoxin Luke

    2016-01-01

    Oxidative stress is known to play an important role in oral cancer development. In this study we aimed to examine whether a chemical activator of NRF2, sulforaphane (SFN), may have chemopreventive effects on oxidative stress-associated oral carcinogenesis. We first showed that Nrf2 activation and oxidative damage were commonly seen in human samples of oral leukoplakia. With gene microarray and immunostaining, we found 4-nitroquinoline 1-oxide (4NQO) in drink activated the Nrf2 pathway and produced oxidative damage in mouse tongue. Meanwhile whole exome sequencing of mouse tongue identified mutations consistent with 4NQO's mutagenic profile. Using cultured human oral keratinocytes and 4NQO-treated mouse tongue, we found that SFN pre-treatment activated the NRF2 pathway and inhibited oxidative damage both in vitro and in vivo. On the contrary, a structural analogue of SFN without the isothiocyanate moiety did not have such effects. In a long-term chemoprevention study using wild-type and Nrf2-/- mice, we showed that topical application of SFN activated the NRF2 pathway, inhibited oxidative damage, and prevented 4NQO-induced oral carcinogenesis in an Nrf2-dependent manner. Our data clearly demonstrate that SFN has chemopreventive effects on oxidative stress-associated oral carcinogenesis, and such effects depend on Nrf2 and the isothiocyanate moiety. PMID:27447968

  14. Dihydroartemisinin and its derivative induce apoptosis in acute myeloid leukemia through Noxa-mediated pathway requiring iron and endoperoxide moiety

    PubMed Central

    Zhao, Xuan; Zhong, Hang; Wang, Rui; Liu, Dan; Waxman, Samuel; Zhao, Linxiang; Jing, Yongkui

    2015-01-01

    Anti-apoptotic protein Mcl-1 plays an important role in protecting cell from death in acute myeloid leukemia (AML). The apoptosis blocking activity of Mcl-1 is inhibited by BH3-only protein Noxa. We found that dihydroartemisinin (DHA) and its derivative X-11 are potent apoptosis inducers in AML cells and act through a Noxa-mediate pathway; X-11 is four-fold more active than DHA. DHA and X-11-induced apoptosis is associated with induction of Noxa; apoptosis is blocked by silencing Noxa. DHA and X-11 induce Noxa expression by upregulating the transcription factor FOXO3a in a reactive oxygen species-mediated pathway. Interfering with the integrity of the endoperoxide moiety of DHA and X-11, as well as chelating intracellular iron with deferoxamine, diminish apoptosis and Noxa induction. AML cells expressing Bcl-xL, or with overexpression of Bcl-2, have decreased sensitivity to DHA and X-11-induced apoptosis which could be overcome by addition of Bcl-2/Bcl-xL inhibitor ABT-737. DHA and X-11 represent a new group of AML cells-apoptosis inducing compounds which work through Noxa up-regulation utilizing the specific endoperoxide moiety and intracellular iron. PMID:25714024

  15. Characterization of pneumolysin from Streptococcus pneumoniae, interacting with carbohydrate moiety and cholesterol as a component of cell membrane.

    PubMed

    Lim, Jong Eun; Park, Seong Ah; Bong, Seoung Min; Chi, Young Min; Lee, Ki Seog

    2013-01-11

    The cytolytic mechanism of cholesterol-dependent cytolysins (CDCs) requires the presence of cholesterol in the target cell membrane. Membrane cholesterol was thought to serve as the common receptor for these toxins, but not all CDCs require cholesterol for binding. One member of this toxin family, pneumolysin (PLY) is a major virulence factor of Streptococcus pneumoniae, and the mechanism via which PLY binds to its putative receptor or cholesterol on the cell membrane is still poorly understood. Here, we demonstrated that PLY interacted with carbohydrate moiety and cholesterol as a component of the cell membrane, using the inhibitory effect of hemolytic activity. The hemolytic activity of PLY was inhibited by cholesterol-MβCD, which is in a 3β configuration at the C3-hydroxy group, but is not in a 3α-configuration. In the interaction between PLY and carbohydrate moiety, the mannose showed a dose-dependent increase in the inhibition of PLY hemolytic activity. The binding ability of mannose with truncated PLYs, as determined by the pull-down assay, showed that mannose might favor binding to domain 4 rather than domains 1-3. These studies provide a new model for the mechanism of cellular recognition by PLY, as well as a foundation for future investigations into whether non-sterol molecules can serve as receptors for other members of the CDC family of toxins. Copyright © 2012 Elsevier Inc. All rights reserved.

  16. Towards technical interoperability in telemedicine.

    SciTech Connect

    Craft, Richard Layne, II

    2004-05-01

    For telemedicine to realize the vision of anywhere, anytime access to care, the question of how to create a fully interoperable technical infrastructure must be addressed. After briefly discussing how 'technical interoperability' compares with other types of interoperability being addressed in the telemedicine community today, this paper describes reasons for pursuing technical interoperability, presents a proposed framework for realizing technical interoperability, identifies key issues that will need to be addressed if technical interoperability is to be achieved, and suggests a course of action that the telemedicine community might follow to accomplish this goal.

  17. Two-dimensional NMR spectroscopy links structural moieties of soil organic matter to the temperature sensitivity of its decomposition

    NASA Astrophysics Data System (ADS)

    Soucemarianadin, Laure; Erhagen, Björn; Öquist, Mats; Nilsson, Mats; Schleucher, Jürgen

    2015-04-01

    Soil organic matter (SOM) represents a huge carbon pool, specifically in boreal ecosystems. Warming-induced release of large amounts of CO2 from the soil carbon pool might become a significant exacerbating feedback to global warming, if decomposition rates of boreal soils were more sensitive to increased temperatures. Despite a large number of studies dedicated to the topic, it has proven difficult to elucidate how the organo-chemical composition of SOM influences its decomposition, or its quality as a substrate for microbial metabolism. A great part of this challenge results from our inability to achieve a detailed characterization of the complex composition of SOM on the level of molecular structural moieties. 13C nuclear magnetic resonance (NMR) spectroscopy is a common tool to characterize SOM. However, SOM is a very complex mixture and the chemical shift regions distinguished in the 13C NMR spectra often represent many different molecular fragments. For example, in the carbohydrates region, signals of all monosaccharides present in many different polymers overlap. This overlap thwarts attempts to identify molecular moieties, resulting in insufficient information to characterize SOM composition. We applied two-dimensional (2D) NMR to characterize SOM with highly increased resolution. We directly dissolved finely ground litters and forest floors'fibric and humic horizons'of both coniferous and deciduous boreal forests in dimethyl sulfoxide and analyzed the resulting solution with a 2D 1H-13C NMR experiment. In the 2D planes of these spectra, signals of CH groups can be resolved based on their 13C and 1H chemical shifts, hence the resolving power and information content of these NMR spectra is hugely increased. The 2D spectra indeed resolved overlaps observed in 1D 13C spectra, so that hundreds of distinct CH groups could be observed and many molecular fragments could be identified. For instance, in the aromatics region, signals from individual lignin units could

  18. Technical Writing: Past, Present and Future

    NASA Technical Reports Server (NTRS)

    Mathes, J. C. (Compiler); Pinelli, T. E. (Compiler)

    1981-01-01

    The training of technical writers and the objectives of such education are discussed. Special emphasis was placed on the communication between technical personnel and non-technical personnel. The liabilities that affect technical writers were also discussed.

  19. PREPARING A TECHNICAL REPORT ON AN INVESTIGATION

    DTIC Science & Technology

    Contents: Importance of technical report writing; General report categories and coverage; Processing the report; Structure and contents of reports...Technical description; Use of tables, graphs, and illustrations; Mechanics of writing technical reports; Typing the technical report .

  20. Cybernetica Qualified: Technical vs. Creative Writing.

    ERIC Educational Resources Information Center

    Meis, Ben H.

    1984-01-01

    Discusses the similarities and differences between the kind of writing that is commonly taught in English courses (composition, creative writing) and that taught in technical education classes (technical report writing, technical communications); and between creative and technical writers. (DMM)

  1. Final Technical Report

    SciTech Connect

    Sobecky, Patricia A; Taillefert, Martial

    2013-03-29

    This final technical report describes results and findings from a research project to examine the role of microbial phosphohydrolase enzymes in naturally occurring subsurface microorganisms for the purpose of promoting the immobilization of the radionuclide uranium through the production of insoluble uranium phosphate minerals. The research project investigated the microbial mechanisms and the physical and chemical processes promoting uranium biomineralization and sequestration in oxygenated subsurface soils. Uranium biomineralization under aerobic conditions can provide a secondary biobarrier strategy to immobilize radionuclides should the metal precipitates formed by microbial dissimilatory mechanisms remobilize due to a change in redox state.

  2. Robotics Technical Note 102.

    DTIC Science & Technology

    1981-06-01

    IAfl-AIBZ 4U2 AIR FORCE BUSINESS RESEARCH MANAGEMENT CENTER WRIGHT-ETC F/6 13/8 I ROBOTICS TECHNIICAL NOTE 102.(U) JUN Al B M BLABIERSALL UNCLASSIFE...CATALOG uME 1T4.T7- Subtitle S. TYPE OF REPOR & PERIOO COVERED Technical Note 102 Robotics 𔄁 FInal r ---- 6. PERFORMING O1G. REPORT NUMBER C 7. A tNORa B...Identify by block number) Robotics Manufacturing Industrial Robots Robot Technology SRobotics Application BQ~.STRACT (Continue on revere* side It

  3. RADTRAN 6 Technical Manual

    SciTech Connect

    Weiner, Ruth F.; Neuhauser, Karen Sieglinde; Heames, Terence John; O'Donnell, Brandon M.; Dennis, Matthew L.

    2014-01-01

    This Technical Manual contains descriptions of the calculation models and mathematical and numerical methods used in the RADTRAN 6 computer code for transportation risk and consequence assessment. The RADTRAN 6 code combines user-supplied input data with values from an internal library of physical and radiological data to calculate the expected radiological consequences and risks associated with the transportation of radioactive material. Radiological consequences and risks are estimated with numerical models of exposure pathways, receptor populations, package behavior in accidents, and accident severity and probability.

  4. RADTRAN 6 technical manual.

    SciTech Connect

    Weiner, Ruth F.; Neuhauser, Karen Sieglinde; Heames, Terence John; O'Donnell, Brandon M.; Dennis, Matthew L.

    2014-01-01

    This Technical Manual contains descriptions of the calculation models and mathematical and numerical methods used in the RADTRAN 6 computer code for transportation risk and consequence assessment. The RADTRAN 6 code combines user-supplied input data with values from an internal library of physical and radiological data to calculate the expected radiological consequences and risks associated with the transportation of radioactive material. Radiological consequences and risks are estimated with numerical models of exposure pathways, receptor populations, package behavior in accidents, and accident severity and probability.

  5. Receptors for oxidized low-density lipoprotein on elicited mouse peritoneal macrophages can recognize both the modified lipid moieties and the modified protein moieties: Implications with respect to macrophage recognition of apoptotic cells

    PubMed Central

    Bird, David A.; Gillotte, Kristin L.; Hörkkö, Sohvi; Friedman, Peter; Dennis, Edward A.; Witztum, Joseph L.; Steinberg, Daniel

    1999-01-01

    It has been shown previously that the binding of oxidized low-density lipoprotein (OxLDL) to resident mouse peritoneal macrophages can be inhibited (up to 70%) by the apoprotein B (apoB) isolated from OxLDL, suggesting that macrophage recognition of OxLDL is primarily dependent on its modified protein moiety. However, recent experiments have demonstrated that the lipids isolated from OxLDL and reconstituted into a microemulsion can also strongly inhibit uptake of OxLDL (up to 80%). The present studies show that lipid microemulsions prepared from OxLDL bind to thioglycollate-elicited macrophages at 4°C in a saturable fashion and inhibit the binding of intact OxLDL and also of the apoB from OxLDL. Reciprocally, the binding of the OxLDL-lipid microemulsions was strongly inhibited by intact OxLDL. A conjugate of synthetic 1-palmitoyl 2(5-oxovaleroyl) phosphatidylcholine (an oxidation product of 1-palmitoyl 2-arachidonoyl phosphatidylcholine) with serum albumin, shown previously to inhibit macrophage binding of intact OxLDL, also inhibited the binding of both the apoprotein and the lipid microemulsions prepared from OxLDL. Finally, a monoclonal antibody against oxidized phospholipids, one that inhibits binding of intact OxLDL to macrophages, also inhibited the binding of both the resolubilized apoB and the lipid microemulsions prepared from OxLDL. These studies support the conclusions that: (i) at least some of the macrophage receptors for oxidized LDL can recognize both the lipid and the protein moieties; and (ii) oxidized phospholipids, in the lipid phase of the lipoprotein and/or covalently linked to the apoB of OxLDL, likely play a role in that recognition. PMID:10339590

  6. Muscle-Type Nicotinic Receptor Modulation by 2,6-Dimethylaniline, a Molecule Resembling the Hydrophobic Moiety of Lidocaine

    PubMed Central

    Alberola-Die, Armando; Fernández-Ballester, Gregorio; González-Ros, José M.; Ivorra, Isabel; Morales, Andrés

    2016-01-01

    To identify the molecular determinants responsible for lidocaine blockade of muscle-type nAChRs, we have studied the effects on this receptor of 2,6-dimethylaniline (DMA), which resembles lidocaine’s hydrophobic moiety. Torpedo marmorata nAChRs were microtransplanted to Xenopus oocytes and currents elicited by ACh (IACh), either alone or co-applied with DMA, were recorded. DMA reversibly blocked IACh and, similarly to lidocaine, exerted a closed-channel blockade, as evidenced by the enhancement of IACh blockade when DMA was pre-applied before its co-application with ACh, and hastened IACh decay. However, there were marked differences among its mechanisms of nAChR inhibition and those mediated by either the entire lidocaine molecule or diethylamine (DEA), a small amine resembling lidocaine’s hydrophilic moiety. Thereby, the IC50 for DMA, estimated from the dose-inhibition curve, was in the millimolar range, which is one order of magnitude higher than that for either DEA or lidocaine. Besides, nAChR blockade by DMA was voltage-independent in contrast to the increase of IACh inhibition at negative potentials caused by the more polar lidocaine or DEA molecules. Accordingly, virtual docking assays of DMA on nAChRs showed that this molecule binds predominantly at intersubunit crevices of the transmembrane-spanning domain, but also at the extracellular domain. Furthermore, DMA interacted with residues inside the channel pore, although only in the open-channel conformation. Interestingly, co-application of ACh with DEA and DMA, at their IC50s, had additive inhibitory effects on IACh and the extent of blockade was similar to that predicted by the allotopic model of interaction, suggesting that DEA and DMA bind to nAChRs at different loci. These results indicate that DMA mainly mimics the low potency and non-competitive actions of lidocaine on nAChRs, as opposed to the high potency and voltage-dependent block by lidocaine, which is emulated by the hydrophilic DEA

  7. Technical Abstracts, 1988

    SciTech Connect

    Kotowski, M.

    1989-05-01

    This document is a compilation of the abstracts from unclassified documents published by Mechanical Engineering at Lawrence Livermore National Laboratory (LLNL) during the calendar year 1988. Many abstracts summarize work completed and published in report form. These are UCRL-90,000 and 100,000 series documents, which include the full text of articles to be published in journals and of papers to be presented at meetings, and UCID reports, which are informal documents. Not all UCIDs contain abstracts: short summaries were generated when abstracts were not included. Technical Abstracts also provides brief descriptions of those documents assigned to the MISC (miscellaneous) category. These are generally viewgraphs or photographs presented at meetings. The abstracts cover the broad range of technologies within Mechanical Engineering and are grouped by the principal author's division. An eighth category is devoted to abstracts presented at the CUBE symposium sponsored jointly by LLNL, Los Alamos National Laboratory, and Sandia Laboratories. Within these areas, abstracts are listed numerically. An author index and title index are provided at the back of the book for cross referencing. The publications listed may be obtained by contacting LLNL's TID library or the National Technical Information Service, US Department of Commerce, 5285 Port Royal Road, Springfield, VA 22161. Further information may be obtained by contacting the author directly or the persons listed in the introduction of each subject area.

  8. Molecular insight in the purification of immunoglobulin by pseudobiospecific ligand l-histidine and histidyl moieties in histidine ligand affinity chromatography (HLAC) by molecular docking.

    PubMed

    Savane, Tushar S; Kumar, Sanjit; Janakiraman, Vignesh Narasimhan; Kamalanathan, Agamudi S; Vijayalakshmi, Mookambeswaran A

    2016-05-15

    Pseudobiospecific ligand l-histidine is an inexpensive, highly stable, non-toxic ligand explored successfully over the last twenty years for the purification of immunoglobulins in immobilised histidine ligand affinity chromatography. It is of great interest to know the molecular recognition sites of IgG to immobilized l-histidine. Here, we have used an in silico approach to explore the molecular recognition of l-histidine by IgG. We have assessed the feasible binding modes of histidine and its moieties at different sites of IgG and considered only those binding conformations which are exhibited via the imidazole ring NH group or any other OH donating group apart from the ones which are terminally conjugated with the support matrix. We categorised binding site into two categories; category I: inner binding groove and category II: surface binding groove and observed that the hinge region of IgG has most favourable binding pocket for l-histidine and histidyl moieties. Ser and Tyr residues on the hinge region make several significant interactions with l-histidine and histidyl moieties. In case of Fc region of IgG, l-histidine and histidyl moieties closely resemble the binding modes of Protein A, biomimetic ligand 22/8 and B domain of SpA to IgG. In addition to these we have also observed a significant binding site for l-histidine and histidyl moieties at Fab region of IgG.

  9. 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

  10. Novel blue emitters based on anthracene derivatives with naphthalene and phenylquinoline moieties for organic light-emtting diodes

    NASA Astrophysics Data System (ADS)

    Park, Soo Na; Bee Lee, Seul; Kim, Chanwoo; Lee, Ho Won; Kim, Young Kwan; Yoon, Seung Soo

    2015-06-01

    In this study, we have designed three blue emitters based on anthracene derivatives with electron withdrawing phenylquinoline moieties. To explore the electroluminescence properties of these materials as blue materials, multilayer blue organic light-emtting diodes (OLEDs) were fabricated in the following device structure: indium-tin-oxide (ITO)/4,4‧-bis[N-(1-naphthyl)-N-phenylamino]biphenyl (NPB)/blue emitters (30 nm) bathophenanthroline (Bphen) (35 nm)/lithium quinolate (Liq) (2 nm)/Al. Among those, a device using 4-{4-[10-(naphthalen-2-yl)anthracen-9-yl]phenyl}-2-phenylquinoline exhibited efficient blue emission with a luminous and power efficiency of 1.59 cd/A and 0.89 lm/W at 20 mA/cm2, respectively. The commission internationale de l’éclairage (CIE) coordinates of this device were (x = 0.17, y = 0.21) at 7.5 V.

  11. Synthesis of 4-methylcoumarin derivatives containing 4,5-dihydropyrazole moiety to scavenge radicals and to protect DNA.

    PubMed

    Xiao, Chuan; Luo, Xu-Yang; Li, De-Jun; Lu, Hang; Liu, Zai-Qun; Song, Zhi-Guang; Jin, Ying-Hua

    2012-07-01

    A series of 4-methylcoumarin derivatives containing 4,5-dihydropyrazole moiety were synthesized and their antioxidant activities were evaluated in AAPH (2,2'-azobis(2-amidinopropane hydrochloride))-induced oxidation of DNA, and in trapping DPPH (2,2'-diphenyl-1-picrylhydrazyl) and ABTS(+•) (2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonate) cationic radical), respectively. Among coumarin derivatives, 3a-d and 4a-c exhibited the termination of radical propagation-chains in AAPH-induced oxidation of DNA. The ortho dihydroxyphenyl substitution at 5 position and 1-unsubstitution of the 4,5-dihydroxylpyrazole was found enhancing the antioxidant activities of these coumarin derivatives. Copyright © 2012 Elsevier Masson SAS. All rights reserved.

  12. Photoelectric and electrical properties of soluble polyphenylquinolines containing an oxygen or phenylamine bridge group between quinoline moieties

    SciTech Connect

    Aleksandrova, E. L.; Svetlychnyi, V. M. Miagkova, L. A.; Nekrasova, T. N.; Tameev, A. R.; Vannikov, A. V.; Kudryavtsev, V. V.

    2009-03-15

    Photoelectric and electrical properties of polyphenylquinolines differing in the structure of donor bridge groups between quinoline moieties have been studied. It is demonstrated that films of the polymers synthesized exhibit a photosensitivity at the level of 10{sup 5} cm{sup 2} J{sup -1} (integrated sensitivity 5 x 10{sup -4} lx{sup -1} . s{sup -1}), with a quantum yield of carrier photogeneration of 0.07 and a carrier drift mobility on the order of 10{sup -6} cm{sup 2} V{sup -1} s{sup -1}. The fact that the electron and hole drift mobilities in polyphenylquinoline with a phenylamine bridge group are balanced makes the polymer promising for development of film-type devices based on the bipolar conductivity of a material (e.g., single-layer light-emitting diode)

  13. Synthesis and biological evaluation of novel formyl-pyrazoles bearing coumarin moiety as potent antimicrobial and antioxidant agents.

    PubMed

    Nagamallu, Renuka; Kariyappa, Ajay Kumar

    2013-12-01

    A series of coumarin appended formyl-pyrazoles 14-18 were synthesized by a simple and accessible approach. The reaction of 8-acetyl-4-methyl-7-hydroxy coumarin 3 and phenyl hydrazine hydrochlorides 4-8 produces the intermediate compounds 8-acetyl-4-methyl-7-hydroxy coumarin hydrazones 9-13. The reaction of compounds 9-13 and DMF in the presence of POCl3 yielded formyl-pyrazoles bearing coumarin moiety 14-18 in good yield. The synthesized new compounds 14-18 and the intermediates 8-acetyl-4-methyl-7-hydroxy coumarin hydrazones 9-13 prepared were screened in vitro for their antibacterial, antifungal antioxidant activities. The compounds 12 and 17 having chloro substitution exhibited promising antifungal and antibacterial activity against the different organisms tested. The compound 17 showed remarkable DPPH radical scavenging ability. Copyright © 2013 Elsevier Ltd. All rights reserved.

  14. [Multiple forms of certain enzymes result post-translationally by a modification of sugar or protein moieties].

    PubMed

    Komoda, T; Koyama, I

    1995-05-01

    Multiple forms of a certain enzyme may result from at least two mechanisms: first, allozymes are coded by distinct genes which exist in separate locus on the chromosome or processed by shuffling of distinct exons on the same genome, and second is this subject, so-called isozymes biosynthesized from single gene subsequently become distinguishable from each other as a result of post-translational modification by protease cleavage (CK), deamidation (AMY) and sugar (ALP, GGT, AMY) or GPI-anchor (ALP) moieties attaching to the enzyme molecules. Therefore, it is interesting to speculate whether alternative forms of the above-mentioned enzymes are true isozymes synthesized from a mRNA from single and/or different cells. In this section, the current topics of these isozymes are commented or discussed.

  15. Discovery of a Potent and Selective DGAT1 Inhibitor with a Piperidinyl-oxy-cyclohexanecarboxylic Acid Moiety

    PubMed Central

    2014-01-01

    We report the discovery of a novel series of DGAT1 inhibitors in the benzimidazole class with a piperdinyl-oxy-cyclohexanecarboxylic acid moiety. This novel series possesses significantly improved selectivity against the A2A receptor, no ACAT1 off-target activity at 10 μM, and higher aqueous solubility and free fraction in plasma as compared to the previously reported pyridyl-oxy-cyclohexanecarboxylic acid series. In particular, 5B was shown to possess an excellent selectivity profile by screening it against a panel of more than 100 biological targets. Compound 5B significantly reduces lipid excursion in LTT in mouse and rat, demonstrates DGAT1 mediated reduction of food intake and body weight in mice, is negative in a 3-strain Ames test, and appears to distribute preferentially in the liver and the intestine in mice. We believe this lead series possesses significant potential to identify optimized compounds for clinical development. PMID:25349648

  16. D-π-A Compounds with Tunable Intramolecular Charge Transfer Achieved by Incorporation of Butenolide Nitriles as Acceptor Moieties.

    PubMed

    Moreno-Yruela, Carlos; Garín, Javier; Orduna, Jesús; Franco, Santiago; Quintero, Estefanía; López Navarrete, Juan T; Diosdado, Beatriz E; Villacampa, Belén; Casado, Juan; Andreu, Raquel

    2015-12-18

    Chromophores where a polyenic spacer separates a 4H-pyranylidene or benzothiazolylidene donor and three different butenolide nitriles have been synthesized and characterized. The role of 2(5H)-furanones as acceptor units on the polarization and the second-order nonlinear (NLO) properties has been studied. Thus, their incorporation gives rise to moderately polarized structures with NLO responses that compare favorably to those of related compounds featuring more efficient electron-withdrawing moieties. Derivatives of the proaromatic butenolide PhFu show the best nonlinearities. Benzothiazolylidene-containing chromophores present less alternated structures than their pyranylidene analogues, and, unlike most merocyanines, the degree of charge transfer does not decrease on lengthening the π-bridge.

  17. Synthesis of the nucleoside moiety of liposidomycins: elucidation of the pharmacophore of this family of MraY inhibitors.

    PubMed

    Dini, C; Collette, P; Drochon, N; Guillot, J C; Lemoine, G; Mauvais, P; Aszodi, J

    2000-08-21

    Tunicamycins (TCMs) and liposidomycins (LPMs) are naturally occurring inhibitors of the bacterial translocase (MraY). Based on structure-activity relationship (SAR) studies, a molecular model has been proposed for their inhibitory mechanism. This study points out the importance of the nucleoside moiety of liposidomycins in the inhibition of MraY. A simplified molecule (I) based on the liposidomycin core structure has been synthesised and tested on MraY. The compound displayed a moderate inhibitory activity (IC50 = 50 microM). The validation of the molecular model was then performed by synthesising higher homologues of I, containing an additional stereocentre in the 5' position (XIV and XV). In agreement with the prediction, only the (S) isomer XV showed significant activity against MraY (IC50 = 5 microM).

  18. Synthesis of new Schiff bases bearing 1,2,4-triazole, thiazolidine and chloroazetidine moieties and their pharmacological evaluation.

    PubMed

    Kandile, Nadia G; Mohamed, Mansoura I; Ismaeel, Hind M

    2017-12-01

    New compounds based on oxindole moiety were synthesized via the reaction of 5-substitued isatins 1a-e with different nucleophiles such as benzidine, 3,3'-dimethoxybenzidine 2a,b and 2,6-diaminopyridine 3 to afford three different classes of bis-Schiff bases 4a-e, 5a-e and 6a-e, respectively. The structures of the new compounds were elucidated on the basis of their FTIR, (1)H NMR, (13)C NMR, GC/MS spectral data and elemental analysis. The in vitro antimicrobial activity of the new compounds was evaluated using a broth dilution technique in terms of minimal inhibitory concentration (MIC) against four bacterial and two fungal pathogens and anticancer activities against HELA cervix. The revealed data showed that compound 9d has excellent activity against Gram + ve and Gram -ve bacteria, and compounds 11b presented promising anticancer activity against HELA cervix. [Formula: see text].

  19. DNA cleavage by homo- and heterotetranuclear Cu(II) and Mn(II) complexes with tetrathioether-tetrathiol moiety.

    PubMed

    Dülger, S; Saglam, N; Beldüz, A O; Güner, S; Karaböcek, S

    2000-09-01

    Novel homotetranuclear Cu(II) and heteronuclear Cu(II)-Mn(II) complexes with tetrathioether-tetrathiol moiety have been prepared and their DNA relaxation activities with plasmid pCYTEXP (5kb) were electrophoretically established. The cleavage products analyzed by neutral agarose gel electrophoresis indicated that the interaction of the metal complexes with supercoiled plasmid DNA yielded linear, nicked or degraded DNA. The relaxation activities of both homo- and heterotetranuclear (SK4) complexes are time- and concentration-dependent. The findings suggest that SK4 with potent nucleolytic activity is a good nuclease substitute in the presence ofcooxidant. Furthermore, the observation of induction of DNA into smaller fragments by SK4 is also significant.

  20. CYTOCHROME P450 REGULATION: THE INTERPLAY BETWEEN ITS HEME AND APOPROTEIN MOIETIES IN SYNTHESIS, ASSEMBLY, REPAIR AND DISPOSAL123

    PubMed Central

    Correia, Maria Almira; Sinclair, Peter R.; De Matteis, Francesco

    2011-01-01

    Heme is vital to our aerobic universe. Heme cellular content is finely tuned through an exquisite control of synthesis and degradation. Heme deficiency is deleterious to cells, whereas excess heme is toxic. Most of the cellular heme serves as the prosthetic moiety of functionally diverse hemoproteins, including cytochromes P450 (P450s). In the liver, P450s are its major consumers with >50% of hepatic heme committed to their synthesis. Prosthetic heme is the sine qua non of P450 catalytic biotransformation of both endo- and xenobiotics. This well-recognized functional role notwithstanding, heme also regulates P450 protein synthesis, assembly, repair and disposal. These less well-appreciated aspects are reviewed herein. PMID:20860521

  1. New Poly(amide-imide)/Nanocomposites Reinforced Silicate Nanoparticles Based on N-pyromellitimido-L-phenyl Alanine Containing Ether Moieties

    NASA Astrophysics Data System (ADS)

    Faghihi, Khalil; Shabanian, Meisam; Dadfar, Ehsan

    2012-02-01

    A series of Poly(amide-imide)/montmorillonite nanocomposites containing N-pyromellitimido-L-phenyl alanine moiety in the main chain were synthesized by a convenient solution intercalation technique. Poly(amide-imide) (PAI) 5 as a source of polymer matrix was synthesized by the direct polycondensation reaction of N-pyromellitimido-L-phenyl alanine 3 with 4,4'-diamino diphenyl ether 4 in the presence of triphenyl phosphite (TPP), CaCl2, pyridine and N-methyl-2-pyrrolidone (NMP). The resulting nanocomposite films were characterized by Fourier transform infrared spectra (FT-IR), X-ray diffraction (XRD), scanning electron microscopy (SEM) and thermogravimetric analysis (TGA). The results showed that organo-modified clay was dispersed homogeneously in PAI matrix. TGA indicated an enhancement of thermal stability of new nanocomposites compared with the pure polymer.

  2. Investigating the use of endogenous quinoid moieties on carbon fibre as means of developing micro pH sensors.

    PubMed

    Anderson, Ashleigh; Phair, Jolene; Benson, John; Meenan, Brian; Davis, James

    2014-10-01

    The redox profile obtained from electrochemically oxidised carbon fibre was exploited as a foundation from which to design a reusable pH probe. X-ray photoelectron spectroscopy of the surface after anodisation revealed an increase in the population of endogenous quinone moieties. Square wave voltammograms recorded in various buffer solutions (pH3-9) yielded a distinct and unambiguous oxidation process through which to ascribe the peak potential - with the latter found to shift in a sub-Nernstian (-0.052 V/pH) manner. The design of a discrete 2-electrode reusable probe which provides a rapid assessment of pH is described and a preliminary characterisation of the electrochemical performance is critically assessed. Copyright © 2014 Elsevier B.V. All rights reserved.

  3. Combinatorial Strategy to Identify Fluorescent Probes for Biothiol and Thiophenol Based on Diversified Pyrimidine Moieties and Their Biological Applications.

    PubMed

    Xie, Xilei; Li, Mengmeng; Tang, Fuyan; Li, Yong; Zhang, Leilei; Jiao, Xiaoyun; Wang, Xu; Tang, Bo

    2017-03-07

    We present a feasible paradigm of developing original fluorescent probes for target biomolecules via combinatorial chemistry. In this developmental program, pyrimidine moieties were investigated and optimized as unique recognition units for thiols for the first time through a parallel synthesis in combination with a rapid screening process. This time-efficient and cost-saving process effectively facilitated the developmental progress and provided detailed structure-reactivity relationships. As a result, Res-Biot and Flu-Pht were identified as optimal fluorescent probes for biothiol and thiophenol, respectively. Their favorable characteristics and superior applicability have been well demonstrated in both chemical and biological contexts. In particular, Res-Biot enables the direct visualization of biothiol fluctuations during oxidative stress and cell apoptosis, indicating its suitability in elucidation of a specific pathophysiological process in both living cells and living animals. Meanwhile, Flu-Pht is competent to visualize thiophenols without the interference from endogenous biothiols in living cells.

  4. 3D printed modular centrifugal contactors and method for separating moieties using 3D printed optimized surfaces

    DOEpatents

    Wardle, Kent E.

    2017-08-29

    The present invention provides an annular centrifugal contactor, having a housing to receive a plurality of liquids; a rotor inside the housing; an annular mixing zone, with a plurality of fluid retention reservoirs; and an adjustable stem that can be raised to restrict the flow of a liquid into the rotor or lowered to increase the flow of liquid into the rotor. The invention also provides a method for transferring moieties from a first liquid to a second liquid, the method having the steps of combining the fluids in a housing whose interior has helically shaped first channels; subjecting the fluids to a spinning rotor to produce a mixture, whereby the channels simultaneously conduct the mixture downwardly and upwardly; and passing the mixture through the rotor to contact second channels, whereby the channels pump the second liquid through a first aperture while the first fluid exits a second aperture.

  5. Synthesis and biological activities of novel pleuromutilin derivatives with a substituted thiadiazole moiety as potent drug-resistant bacteria inhibitors.

    PubMed

    Shang, Ruofeng; Pu, Xiuying; Xu, Ximing; Xin, Zhijun; Zhang, Chao; Guo, Wenzhu; Liu, Yu; Liang, Jianping

    2014-07-10

    A series of novel pleuromutilin derivatives possessing thiadiazole moieties were synthesized via acylation reactions under mild conditions. The in vitro antibacterial activities of the derivatives against methicillin-resistant Staphylococcus aureus, methicillin-resistant Staphylococcus epidermidis, Escherichia coli, and Streptococcus agalactiae were tested by the agar dilution method and Oxford cup assay. The majority of the tested compounds displayed moderate antibacterial activities. Importantly, the three compounds with amino or tertiary amine groups in their side chains, 11, 13b, and 15c, were the most active antibacterial agents. Docking experiments carried out on the peptidyl transferase center (PTC) of 23S rRNA proved that there is a reasonable direct correlation between the binding free energy (ΔGb, kcal/mol) and the antibacterial activity. Moreover, the pharmacokinetic profiles of 11 and 15c in rat were characterized by moderate clearance and oral bioavailability.

  6. Synthesis, antimycobacterial and antibacterial activity of fluoroquinolone derivatives containing an 3-alkoxyimino-4-(cyclopropylanimo)methylpyrrolidine moiety.

    PubMed

    Zhang, Tingting; Shen, Weiyi; Liu, Mingliang; Zhang, Rui; Wang, Minghua; Li, Linhu; Wang, Bin; Guo, Huiyuan; Lu, Yu

    2015-11-02

    A series of novel fluoroquinolone derivatives containing an 3-alkoxyimino-4-(cyclopropylanimo)methylpyrrolidine moiety were designed, synthesized and evaluated for their biological activity. Our results revealed that 19b2 shows good activity against MTB H37Rv ATCC 27294 (MIC: <0.25 μg/mL) and MDR-MTB 6133 clinical isolate (MIC: 0.11 μg/mL). Most of them have potent potency against Gram-positive strains, although they are generally poor active against Gram-negative strains. Especially, compounds 22b1 and 23a3 (MICs: <0.008-8 μg/mL) were found to 2-128 times more potent than ciprofloxacin and levofloxacin against all of the tested Gram-positive strains including quinolone-resistant MRSA, MRSE, Enterococcus faecium and Enterococcus faecalis. Copyright © 2015. Published by Elsevier Masson SAS.

  7. Theoretical pKa prediction of the α-phosphate moiety of uridine 5‧-diphosphate-GlcNAc

    NASA Astrophysics Data System (ADS)

    Vipperla, Bhavaniprasad; Griffiths, Thomas M.; Wang, Xingyong; Yu, Haibo

    2017-01-01

    The pKa value of the α-phosphate moiety of uridine 5‧-diphosphate-GlcNAc (UDP-GlcNAc) has been successfully calculated using density functional theory methods in conjunction with the Polarizable Continuum Models. Theoretical methods were benchmarked over a dataset comprising of alkyl phosphates. B3LYP/6-31+G(d,p) calculations using SMD solvation model provide excellent agreement with the experimental data. The predicted pKa for UDP-GlcNAc is consistent with most recent NMR studies but much higher than what it has long been thought to be. The importance of this study is evident that the predicted pKa for UDP-GlcNAc supports its potential role as a catalytic base in the substrate-assisted biocatalysis.

  8. Toward interaction of sensitizer and functional moieties in hole-transporting materials for efficient semiconductor-sensitized solar cells.

    PubMed

    Im, Sang Hyuk; Lim, Choong-Sun; Chang, Jeong Ah; Lee, Yong Hui; Maiti, Nilkamal; Kim, Hi-Jung; Nazeeruddin, Md K; Grätzel, Michael; Seok, Sang Il

    2011-11-09

    Sb(2)S(3)-sensitized mesoporous-TiO(2) solar cells using several conjugated polymers as hole-transporting materials (HTMs) are fabricated. We found that the cell performance was strongly correlated with the chemical interaction at the interface of Sb(2)S(3) as sensitizer and the HTMs through the thiophene moieties, which led to a higher fill factor (FF), open-circuit voltage (V(oc)), and short-circuit current density (J(sc)). With the application of PCPDTBT (poly(2,6-(4,4-bis-(2-ethylhexyl)-4H-cyclopenta[2,1-b;3,4-b']dithiophene)-alt-4,7(2,1,3-benzothiadiazole)) as a HTM in a Sb(2)S(3)-sensitized solar cell, overall power conversion efficiencies of 6.18, 6.57, and 6.53% at 100, 50, and 10% solar irradiation, respectively, were achieved with a metal mask.

  9. Scapiformolactones A-I: germacrane sesquiterpenoids with an unusual Δ3-15,6-lactone moiety from Salvia scapiformis.

    PubMed

    Lai, Yongji; Xue, Yongbo; Zhang, Mengke; Zhang, Jinwen; Tang, Wei; Liu, Junjun; Lei, Liang; Yan, Juming; Luo, Zengwei; Zuo, Jianping; Li, Yan; Yao, Guangmin; Zhang, Yonghui

    2013-12-01

    Nine germacrane sesquiterpenoids with an unusual Δ(3)-15,6-lactone moiety, scapiformolactones A-I (1-9), and one known seco-germacrane sesquiterpenoid, 3,7,11-trimethyldodeca-l,6,9-triene-3,11-diol (10), were isolated from whole plants of Salvia scapiformis Hance. Their structures were elucidated by spectroscopic methods including HR-ESIMS, IR, UV, NMR, and CD, as well as by quantum mechanical calculations and chemical transformations. Structures of compounds 1-3 were also confirmed by single-crystal X-ray diffraction analysis. Six germacrane 6,15-diol derivatives (11-16) were obtained by chemical transformation. Compounds 1-9 and 11-16 were evaluated for their in vitro immunomodulatory effects on T and B cells, as well as their in vitro cytotoxicity against five human cancer cell lines, HL-60, SMMC-7721, A-549, MCF-7, and SW480.

  10. Direct labeling microRNA with an electrocatalytic moiety and its application in ultrasensitive microRNA assays.

    PubMed

    Gao, Zhiqiang; Yu, Yuan Hong

    2007-01-15

    An ultrasensitive procedure for the detection of microRNA (miRNA) in total RNA is described in this work. The miRNA is directly labeled with a redox active and electrocatalytic moiety, Ru(PD)(2)Cl(2) (PD=1,10-phenanthroline-5,6-dione), through coordinative bonds with purine bases in the miRNA molecule. The excellent electrocatalytic activity of the Ru(PD)(2)Cl(2) towards the oxidation of hydrazine makes it possible to conduct ultrasensitive miRNA detection. Under optimized experimental conditions, the assay allows the detection of miRNAs in the range of 0.50-400 pM with a detection limit of 0.20 pM in 2.5 microl (0.50 amole). MicroRNA quantitation is therefore performed in as little as 10 ng of total RNA, providing a much-needed platform for miRNA expression analysis.

  11. Effect of organic moieties on the scintillation properties of organic-inorganic layered perovskite-type compounds

    NASA Astrophysics Data System (ADS)

    Kawano, Naoki; Koshimizu, Masanori; Horiai, Akiyoshi; Nishikido, Fumihiko; Haruki, Rie; Kishimoto, Shunji; Shibuya, Kengo; Fujimoto, Yutaka; Yanagida, Takayuki; Asai, Keisuke

    2016-11-01

    The effects of organic moieties on the scintillation properties of organic-inorganic layered perovskite-type compounds have been investigated. Three kinds of single crystals were fabricated, namely, (C4H9NH3)2PbBr4 (C4), (C6H5CH2NH3)2PbBr4 (Ben), and (C6H5C2H4NH3)2PbBr4 (Phe). Among the single crystals, the light output of Phe was found to have the greatest value when exposed to X-ray radiation (67.4 keV). The light output of Phe was 0.62 times that of YAP:Ce. The relative values of the light outputs among the fabricated single crystals under X-ray radiation correlated well with those of the quantum efficiencies and the luminescence intensity under ultraviolet radiation.

  12. Discovery of a Potent and Selective DGAT1 Inhibitor with a Piperidinyl-oxy-cyclohexanecarboxylic Acid Moiety.

    PubMed

    He, Shuwen; Hong, Qingmei; Lai, Zhong; Yang, David X; Ting, Pauline C; Kuethe, Jeffrey T; Cernak, Timothy A; Dykstra, Kevin D; Sperbeck, Donald M; Wu, Zhicai; Yu, Yang; Yang, Ginger X; Jian, Tianying; Liu, Jian; Guiadeen, Deodial; Krikorian, Arto D; Sonatore, Lisa M; Wiltsie, Judyann; Liu, Jinqi; Gorski, Judith N; Chung, Christine C; Gibson, Jack T; Lisnock, JeanMarie; Xiao, Jianying; Wolff, Michael; Tong, Sharon X; Madeira, Maria; Karanam, Bindhu V; Shen, Dong-Ming; Balkovec, James M; Pinto, Shirly; Nargund, Ravi P; DeVita, Robert J

    2014-10-09

    We report the discovery of a novel series of DGAT1 inhibitors in the benzimidazole class with a piperdinyl-oxy-cyclohexanecarboxylic acid moiety. This novel series possesses significantly improved selectivity against the A2A receptor, no ACAT1 off-target activity at 10 μM, and higher aqueous solubility and free fraction in plasma as compared to the previously reported pyridyl-oxy-cyclohexanecarboxylic acid series. In particular, 5B was shown to possess an excellent selectivity profile by screening it against a panel of more than 100 biological targets. Compound 5B significantly reduces lipid excursion in LTT in mouse and rat, demonstrates DGAT1 mediated reduction of food intake and body weight in mice, is negative in a 3-strain Ames test, and appears to distribute preferentially in the liver and the intestine in mice. We believe this lead series possesses significant potential to identify optimized compounds for clinical development.

  13. Synthesis, characterization and biological evaluation of some thiourea derivatives bearing benzothiazole moiety as potential antimicrobial and anticancer agents.

    PubMed

    Saeed, Sohail; Rashid, Naghmana; Jones, Peter G; Ali, Muhammad; Hussain, Rizwan

    2010-04-01

    Five series of thiourea derivatives bearing benzothiazole moiety (20 compounds) were efficiently synthesized and evaluated for antimicrobial and anticancer activities. The results indicated that the compounds possessed a broad spectrum of activity against the tested microorganisms and showed higher activity against fungi than bacteria. Compounds 1b, 2b, 3b, 4b and 5b exhibited the greatest antimicrobial activity. Preliminary study of the structure-activity relationship revealed that electronic factors in benzothiazole rings had a great effect on the antimicrobial activity of these compounds. In preliminary MTT cytotoxicity studies, the thiourea derivatives (2d, 5c and 5d) were found most potent. In MCF-7 and HeLa cells, the IC(50) values were observed in the range of 18-26 microM and 38-46 microM, respectively. Copyright (c) 2009 Elsevier Masson SAS. All rights reserved.

  14. 1,4-Dihydropyridine derivatives as calcium channel modulators: the role of 3-methoxy-flavone moiety.

    PubMed

    Budriesi, Roberta; Bisi, Alessandra; Ioan, Pierfranco; Rampa, Angela; Gobbi, Silvia; Belluti, Federica; Piazzi, Lorna; Valenti, Piero; Chiarini, Alberto

    2005-05-16

    It was earlier recognized that calcium antagonists, and in particular 1,4-dihydropyridines, exhibited distinct cardiovascular profiles. In addition two different splice variants of the L-type calcium channel were found in vascular and cardiac tissues. In this study, novel substituted 1,4-dihydropyridines with a 3-methoxy-flavone moiety were synthesized and structural modifications of the substituents in the dihydropyridine ring of nifedipine were carried out in order to find tissue specific compounds. The negative inotropic, chronotropic and vasorelaxant effects were investigated on guinea-pig left, right atria and aortic strips, respectively. The introduction of an heteroaromatic ring in 4-position of the 1,4-dihydropyridine nucleus led to compounds selective for cardiac tissues. Moreover, different residues in the 1,4-dihydropyridine ring could modulate the chronotropic versus inotropic activity.

  15. The B(12)-binding subunit of glutamate mutase from Clostridium tetanomorphum traps the nucleotide moiety of coenzyme B(12).

    PubMed

    Tollinger, M; Eichmüller, C; Konrat, R; Huhta, M S; Marsh, E N; Kräutler, B

    2001-06-08

    Glutamate mutase from Clostridium tetanomorphum binds coenzyme B(12) in a base-off/His-on form, in which the nitrogenous ligand of the B(12)-nucleotide function is displaced from cobalt by a conserved histidine. The effect of binding the B(12)-nucleotide moiety to MutS, the B(12)-binding subunit of glutamate mutase, was investigated using NMR spectroscopic methods. Binding of the B(12)-nucleotide to MutS was determined to occur with K(d)=5.6(+/-0.7) mM and to be accompanied by a specific conformational change in the protein. The nucleotide binding cleft of the apo-protein, which is formed by a dynamic segment with propensity for partial alpha-helical conformation (the "nascent" alpha-helix), becomes completely structured upon binding of the B(12)-nucleotide, with formation of helix alpha1. In contrast, the segment containing the conserved residues of the B(12)-binding Asp-x-His-x-x-Gly motif remains highly dynamic in the protein/B(12)-nucleotide complex. From relaxation studies, the time constant tau, which characterizes the time scale for the formation of helix alpha1, was estimated to be about 30 micros (15)N and was the same in both, apo-protein and nucleotide-bound protein. Thus, the binding of the B(12)-nucleotide moiety does not significantly alter the kinetics of helix formation, but only shifts the equilibrium towards the structured fold. These results indicate MutS to be structured in such a way, as to be able to trap the nucleotide segment of the base-off form of coenzyme B(12) and provide, accordingly, the first structural clues as to how the process of B(12)-binding occurs. Copyright 2001 Academic Press.

  16. The (1->6)-β-glucan moiety represents a cross-reactive epitope of infection-induced malignancy surveillance.

    PubMed

    Dong, Hongliang; Dai, Hui; Hu, Xiaomin; Xiong, Si-Dong; Gao, Xiao-Ming

    2014-02-01

    Exposure to pathogen-associated molecular patterns (PAMPs) by vaccination or infection is known to have beneficial effects on neoplastic diseases, although the underlying molecular mechanisms are so far unclear. In this article, we report that Abs against (1→6)-β-d-glucan, a typical microbial PAMP and a major target for high titer circulating natural Abs in healthy human subjects, cross-recognize a novel tumor-associated carbohydrate Ag on cancer cells. The (1→6)-β-glucan cross-reactive moiety is immunologically dominant in tumor cells, as C57BL/6 mice harboring EL-4 solid tumors produced anti-(1→6)-β-glucan Abs and the titer of which significantly correlated with enhanced survival and smaller tumor burden. Moreover, the (1→6)-β-glucan-specific Abs exhibited potent tumoricidal activities in vitro. C57BL/6 mice immunized with Candida albicans produced protective immunity against inoculated EL-4 tumors, which was attributed to the formation of (1→6)-β-glucan-specific Abs. Importantly, (1→6)-β-glucan-specific Abs significantly prolonged the survival and reduced the tumor size in mice inoculated with EL-4 tumors. Our results demonstrate that the (1→6)-β-glucan cross-reactive moiety represents a focal point between infection immunity and cancer surveillance, and natural Abs against this epitope may contribute to the first-line antitumor surveillance in humans. Our data also provide important explanation for the long-observed relationship between feverish infection and concurrent remission from cancer.

  17. Carbonic anhydrase activators: design of high affinity isozymes I, II, and IV activators, incorporating tri-/tetrasubstituted-pyridinium-azole moieties.

    PubMed

    Ilies, Monica; Banciu, Mircea D; Ilies, Marc A; Scozzafava, Andrea; Caproiu, Miron T; Supuran, Claudiu T

    2002-01-17

    A series of tight binding carbonic anhydrase (CA) activators was obtained by reaction of amino-azoles (3-amino-pyrazole, 2-amino-imidazole, and 5-amino-tetrazole) with tri- or tetrasubstituted pyrylium salts. Many of the new pyridinium salts incorporating azole moieties reported here proved to be efficient in vitro activators of three CA isozymes, CA I, II, and IV. Very good activity was detected against hCA I and bCA IV (h = human; b = bovine isozymes), for which some of the new compounds showed affinities in the low nanomolar range, whereas against hCA II, their affinities were in the range of 95-150 nM. Substitution patterns of the pyridinium ring leading to best activity included 4-phenyl-2,6-dialkyl moieties or 2,4,6-tri- and 2,3,4,6-tetraalkyl groups. Ex vivo experiments showed some of the new activators to strongly enhance CA activity after incubation with human erythrocytes. Furthermore, due to their cationic nature, some of these compounds (the imidazole and pyrazole derivatives) are membrane-impermeant, discriminating thus between cytosolic and membrane-bound CA isozymes. The present paper is the first report of membrane-impermeant CA activators. The pyridinium tetrazole derivatives on the other hand do penetrate through biological membranes. Such CA activators might lead to the development of drugs/diagnostic tools for the management of CA deficiency syndromes as well as for the pharmacological enhancement of synaptic efficacy, spatial learning, and memory. This may constitute a new approach for the treatment of Alzheimer disease and other conditions in need of achieving memory therapy.

  18. 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

  19. 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

  20. 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.

  1. 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

  2. Mechanical engineering department technical review

    SciTech Connect

    Carr, R.B. Denney, R.M.

    1981-01-01

    The Mechanical Engineering Department Technical Review is published to: (1) inform the readers of various technical activities within the department, (2) promote exchange of ideas, and (3) give credit to the personnel who are achieving the results. The report is formatted into two parts: technical acievements and publication abstracts. The first is divided into eight sections, one for each division in the department providing the reader with the names of the personnel and the division accomplishing the work.

  3. Mechanical Engineering Department. Technical review

    SciTech Connect

    Simecka, W.B.; Condouris, R.A.; Talaber, C.

    1980-01-01

    The Mechanical Engineering Department Technical Review is published to (1) inform the readers of various technical activities within the Department, (2) promote exchange of ideas, and (3) give credit to the personnel who are achieving the results. The report is formatted into two parts: technical achievements and publication abstracts. The first is divided into eight sections, one for each Division in the Department providing the reader with the names of the personnel and the Division accomplishing the work.

  4. RF Chain Final Technical Report

    DTIC Science & Technology

    1983-01-01

    UNCLASSIFIED ~SECR1 AFWAL-TR-82-1160 RF CHAIN FINAL TECHNICAL REPORT (U) NORTHROP CORPORATION DEFENSE SYSTEMS DIVISION 600 HICKS ROAD * ROLLING MEADOWS...ILLINOIS 60008 JANUARY 1983 TECHNICAL REPORT AFWAL-TR-82-1160 Final Report for Period October 1979 - October 1982 Distribution Limited to U. S. Government...This technical report has been reviewed and is approved for publication. RICHARD A. HIEBER, Elec. Engr. fiNNETH W. HEL. A chnical Mgr Deception

  5. Mechanical Engineering Department Technical Review

    SciTech Connect

    Carr, R.B.; Denney, R.M.

    1981-07-01

    The Mechanical Engineering Department Technical Review is published to inform readers of various technical activities within the Department, promote exchange of ideas, and give credit to personnel who are achieving the results. The report is presented in two parts: technical achievements and publication abstracts. The first is divided into seven sections, each of which reports on an engineering division and its specific activities related to nuclear tests, nuclear explosives, weapons, energy systems, engineering sciences, magnetic fusion, and materials fabrication.

  6. Mechanical Engineering Department technical abstracts

    SciTech Connect

    Denney, R.M.

    1982-07-01

    The Mechanical Engineering Department publishes listings of technical abstracts twice a year to inform readers of the broad range of technical activities in the Department, and to promote an exchange of ideas. Details of the work covered by an abstract may be obtained by contacting the author(s). Overall information about current activities of each of the Department's seven divisions precedes the technical abstracts.

  7. Final Technical Report

    SciTech Connect

    Eckerlin, H, M, PhD PE; Leach, J, W, PhD PE; Terry, S, D, PhD PE

    2007-02-28

    The Industrial Assessment Center program at North Carolina State University has conducted one hundred industrial assessments of small and medium sized manufacturers in North Carolina, South Carolina, and Virginia. Reports were submitted to each facility that included a brief description of the plant, historical energy use, and a technical analysis of potential energy efficiency savings, waste reduction, and productivity savings. Seven hundred thirty eight conservation measures were recommended with total annual cost savings in excess of $18 million. The NCSU IAC has worked with other government and private entities to deliver energy efficiency and conservation services. We have worked closely with the NCSU Industrial Extension Service, the Manufacturer’s Extension Partnership (MEP), and the North Carolina State Energy Office to provide follow-up technical help and financial assistance in implementing conservation recommendations. In addition to these organizations, the NCSU IAC has also worked with the NC Department of Pollution Prevention and Environmental Assistance, the NC Solar Center, Advanced Energy Corporation, Duke Power, Progress Energy, Dominion Power, and the City of Danville, Virginia. Eighteen undergraduate and twenty graduate students were exposed to a variety of manufacturing processes, trained on plant safety, and taught the use of various types of data collection equipment. The students performed technical analyses of each recommendation, computed the potential savings from engineering relations and collected data, estimated the cost from vendor information, and communicated the findings in a compact, well written report to the client. The students have also been exposed to a variety of business personnel, including corporate presidents, engineering managers, plant managers, plant engineers, facility maintenance staff, and production workers – each with a unique perspective on the challenges faced in a modern manufacturing facility. The program

  8. Technical Assistance to Brownfields Communities

    EPA Pesticide Factsheets

    This notice announces the availability of funds and solicits proposals from eligible entities (including eligible non-profit organizations) to provide technical assistance to communities on brownfields issues.

  9. 77 FR 37284 - Technical Amendments

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-06-21

    ... of Workers' Compensation Programs is making ] technical amendments to reflect the dissolution of the... substantive rule governing administration of these statutes. ESA's dissolution has also necessitated revising...

  10. ERLN Technical Support for Labs

    EPA Pesticide Factsheets

    The Environmental Response Laboratory Network provides policies and guidance on lab and data requirements, Standardized Analytical Methods, and technical support for water and radiological sampling and analysis

  11. Technical advances in hemodialysis therapy.

    PubMed

    Parker, T F

    2000-01-01

    Other than pharmaceutical advancements, the improvements in hemodialysis have largely been due to technical changes. This article summarizes the various technical areas that are noteworthy: hemodialysis membranes; dialysate buffer, electrolyte concentration, and temperature; prescription monitoring; reprocessing; volume-ultrafiltration control; information system interface; arteriovenous access monitoring; water treatment; and continuous and nocturnal dialysis. Within each category, subjective and objective conclusions are drawn as to whether the technical advancements have translated to improved clinical outcomes. In addition, an hypothesis is proposed that due to a confluence of ownership of research and development, manufacturing of equipment, and dialysis facilities conflicts may arise which could slow future technical developments.

  12. Final Technical Report

    SciTech Connect

    John Tanis

    2005-11-25

    This document comprises the final technical report for atomic collisions research supported by DOE grant No. DE-FG02-87ER13778 from September 1, 2001 through August 31, 2004. The research involved the experimental investigation of excitation and charge-changing processes occurring in ion-atom and ion-molecule collisions. Major emphases of the study were: (1) interference effects resulting from coherent electron emission in H2, (2) production of doubly vacant K-shell (hollow ion) states due to electron correlation, and (3) formation of long-lived metastable states in electron transfer processes. During the period of the grant, this research resulted in 23 publications, 12 invited presentations, and 39 contributed presentations at national and international meetings and other institutions. Brief summaries of the completed research are presented below.

  13. Final Technical Report

    SciTech Connect

    Eggeman, Tim; O'Neill, Brian

    2016-08-17

    ZeaChem Inc. and US DOE successfully demonstrated the ZeaChem process for producing sugars and ethanol from high-impact biomass feedstocks. The project was executed over a 5-year period under a $31.25 million cooperative agreement (80:20 Federal:ZeaChem cost share). The project was managed by dividing it into three budget periods. Activities during Budget Period 1 were limited to planning, permitting, and other pre-construction planning. Budget Period 2 activities included engineering, procurement, construction, commissioning, start-up and initial operations through the Independent Engineer Test Runs. The scope of construction was limited to the Chem Frac and Hydrogenolysis units, as the Core Facility was already in place. Construction was complete in December 2012, and the first cellulosic ethanol was produced in February 2013. Additional operational test runs were conducted during Budget Period 3 (completed June 2015) using hybrid poplar, corn stover, and wheat straw feedstocks, resulting in the production of cellulosic ethanol and various other biorefinery intermediates. The research adds to the understanding of the Chem Frac and Hydrogenolysis technologies in that the technical performance of each unit was measured, and the resulting data and operational experience can be used as the basis for engineering designs, thus mitigating risks for deployment in future commercial facilities. The Chem Frac unit was initially designed to be operated as two-stage dilute acid hydrolysis, with first stage conditions selected to remove the hemicellulose fraction of the feedstock, and the second stage conditions selected to remove the cellulose fraction. While the Chem Frac unit met or exceeded the design capacity of 10 ton(dry)/day, the technical effectiveness of the Chem Frac unit was below expectations in its initial two-stage dilute acid configuration. The sugars yields were low, the sugars were dilute, and the sugars had poor fermentability caused by excessive inhibitors

  14. Technical applications of aerogels

    SciTech Connect

    Hrubesh, L.W.

    1997-08-18

    Aerogel materials posses such a wide variety of exceptional properties that a striking number of applications have developed for them. Many of the commercial applications of aerogels such as catalysts, thermal insulation, windows, and particle detectors are still under development and new application as have been publicized since the ISA4 Conference in 1994: e.g.; supercapacitors, insulation for heat storage in automobiles, electrodes for capacitive deionization, etc. More applications are evolving as the scientific and engineering community becomes familiar with the unusual and exceptional physical properties of aerogels, there are also scientific and technical application, as well. This paper discusses a variety of applications under development at Lawrence Livermore National Laboratory for which several types of aerogels are formed in custom sizes and shapes. Particular discussions will focus on the uses of aerogels for physics experiments which rely on the exceptional, sometimes unique, properties of aerogels.

  15. LLNL 1981: technical horizons

    SciTech Connect

    Not Available

    1981-07-01

    Research programs at LLNL for 1981 are described in broad terms. In his annual State of the Laboratory address, Director Roger Batzel projected a $481 million operating budget for fiscal year 1982, up nearly 13% from last year. In projects for the Department of Energy and the Department of Defense, the Laboratory applies its technical facilities and capabilities to nuclear weapons design and development and other areas of defense research that include inertial confinement fusion, nonnuclear ordnances, and particle-beam technology. LLNL is also applying its unique experience and capabilities to a variety of projects that will help the nation meet its energy needs in an environmentally acceptable manner. A sampling of recent achievements by LLNL support organizations indicates their diversity. (GHT)

  16. Technical Report - FINAL

    SciTech Connect

    Barbara Luke, Director, UNLV Engineering Geophysics Laboratory

    2007-04-25

    Improve understanding of the earthquake hazard in the Las Vegas Valley and to assess the state of preparedness of the area's population and structures for the next big earthquake. 1. Enhance the seismic monitoring network in the Las Vegas Valley 2. Improve understanding of deep basin structure through active-source seismic refraction and reflection testing 3. Improve understanding of dynamic response of shallow sediments through seismic testing and correlations with lithology 4. Develop credible earthquake scenarios by laboratory and field studies, literature review and analyses 5. Refine ground motion expectations around the Las Vegas Valley through simulations 6. Assess current building standards in light of improved understanding of hazards 7. Perform risk assessment for structures and infrastructures, with emphasis on lifelines and critical structures 8. Encourage and facilitate broad and open technical interchange regarding earthquake safety in southern Nevada and efforts to inform citizens of earthquake hazards and mitigation opportunities

  17. Final Technical Report

    SciTech Connect

    Klein, Stephen A.

    2003-06-23

    In this final technical report, a summary of work is provided. Concepts were developed for a new statistical cloud parameterization suitable for inclusion into global climate models. These concepts were evaluated by comparison to ARM data and data from cloud resolving models driven by ARM data. The purpose of this grant was to develop a new cloud parameterization for the global climate model of the Geophysical Fluid Dynamics Laboratory (GFDL) of the National Oceanic and Atmospheric Administration (NOAA). Note that uncertainties in cloud parameterizations are a key reason why prediction of climate change from climate models remain unacceptably uncertain. To develop the parameterizations, the observations and models provided by the Department of Energy's Atmospheric Radiation Measurement (ARM) program were analyzed and used.

  18. FINAL/ SCIENTIFIC TECHNICAL REPORT

    SciTech Connect

    McDonald, Henry; Singh, Suminderpal

    2006-08-28

    The overall objective of the Chattanooga fuel cell demonstrations project was to develop and demonstrate a prototype 5-kW grid-parallel, solid oxide fuel cell (SOFC) system that co-produces hydrogen, based on Ion America’s technology. The commercial viability of the 5kW SOFC system was tested by transporting, installing and commissioning the SOFC system at the Alternative Energy Laboratory at the University of Tennessee – Chattanooga. The system also demonstrated the efficiency and the reliability of the system running on natural gas. This project successfully contributed to the achievement of DOE technology validation milestones from the Technology Validation section of the Hydrogen, Fuel Cells and Infrastructure Technologies Program Multi-Year Research, Development and Demonstration Plan. Results of the project can be found in the final technical report.

  19. Technical literature review.

    PubMed

    Nußbeck, Gunnar; Gök, Murat

    2013-01-01

    This review gives a comprehensive overview on the technical perspective of personal health monitoring. It is designed to build a mutual basis for the project partners of the PHM-Ethics project. A literature search was conducted to screen pertinent literature databases for relevant publications. All review papers that were retrieved were analyzed. The increasing number of publications that are published per year shows that the field of personal health monitoring is of growing interest in the research community. Most publications deal with telemonitoring, thus forming the core technology of personal health monitoring. Measured parameters, fields of application, participants and stakeholders are described. Moreover an outlook on information and communication technology that foster the integration possibilities of personal health monitoring into decision making and remote monitoring of individual people's health is provided. The removal of the technological barriers opens new perspectives in health and health care delivery using home monitoring applications.

  20. Predictors of employer satisfaction: technical and non-technical skills.

    PubMed

    Danielson, Jared A; Wu, Tsui-Feng; Fales-Williams, Amanda J; Kirk, Ryan A; Preast, Vanessa A

    2012-01-01

    Employers of 2007-2009 graduates from Iowa State University College of Veterinary Medicine were asked to respond to a survey regarding their overall satisfaction with their new employees as well as their new employees' preparation in several technical and non-technical skill areas. Seventy-five responses contained complete data and were used in the analysis. Four technical skill areas (data collection, data interpretation, planning, and taking action) and five non-technical skill areas (interpersonal skills, ability to deal with legal issues, business skills, making referrals, and problem solving) were identified. All of the skill area subscales listed above had appropriate reliability (Cronbach's alpha>0.70) and were positively and significantly correlated with overall employer satisfaction. Results of two simultaneous regression analyses indicated that of the four technical skill areas, taking action is the most salient predictor of employer satisfaction. Of the five non-technical skill areas, interpersonal skills, business skills, making referrals, and problem solving were the most important skills in predicting employer satisfaction. Hierarchical regression analysis revealed that all technical skills explained 25% of the variation in employer satisfaction; non-technical skills explained an additional 42% of the variation in employer satisfaction.

  1. Scientific and Technical Information. Handbook for Technical Report Preparation

    DTIC Science & Technology

    1991-05-31

    The contents of this publication describes the organization and format of a technical report , and is a compilation of standards, manuals and...regulations pertaining to technical report publication. Attachments 1 through 4 contain report preparation and processing requirements. Attachments 5 through 18 contain examples of report content and format.

  2. Does Being Technical Matter? XML, Single Source, and Technical Communication.

    ERIC Educational Resources Information Center

    Sapienza, Filipp

    2002-01-01

    Describes XML, a recent Web design language that will enable technical communicators to produce documentation that can reuse information and present it across multiple types of media for diverse audiences. Argues that XML requires more interdisciplinary approaches toward the teaching and research of technical communication, particularly with…

  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. Discovery and biological evaluation of some (1H-1,2,3-triazol-4-yl)methoxybenzaldehyde derivatives containing an anthraquinone moiety as potent xanthine oxidase inhibitors.

    PubMed

    Zhang, Ting-Jian; Li, Song-Ye; Yuan, Wei-Yan; Wu, Qing-Xia; Wang, Lin; Yang, Su; Sun, Qi; Meng, Fan-Hao

    2017-02-15

    A series of (1H-1,2,3-triazol-4-yl)methoxybenzaldehyde derivatives containing an anthraquinone moiety were synthesized and identified as novel xanthine oxidase inhibitors. Among them, the most promising compounds 1h and 1k were obtained with IC50 values of 0.6μM and 0.8μM, respectively, which were more than 10-fold potent compared with allopurinol. The Lineweaver-Burk plot revealed that compound 1h acted as a mixed-type xanthine oxidase inhibitor. SAR analysis showed that the benzaldehyde moiety played a more important role than the anthraquinone moiety for inhibition potency. The basis of significant inhibition of xanthine oxidase by 1h was rationalized by molecular modeling studies.

  5. A biphenyl containing two electron-donating and two electron-accepting moieties: a rigid and small donor-acceptor-donor ladder system.

    PubMed

    Greulich, Tobias W; Suzuki, Naoya; Daniliuc, Constantin G; Fukazawa, Aiko; Yamaguchi, Eriko; Studer, Armido; Yamaguchi, Shigehiro

    2016-02-07

    Ladder π-conjugated materials and also push-pull systems belong to important classes of compounds for the development of organic electronic devices. In this communication, a novel π-conjugated material that unifies the properties of both of these classes is presented. The material comprises a rigid biphenyl framework, which bears two bridging electron-accepting phosphine oxide moieties as well as two electron-donating amino groups. The structure and photophysical properties of this compound are discussed and compared with those of a related system lacking the second P-moiety.

  6. Insights into the structure-activity relationship of the anticancer compound ZJ-101, a derivative of marine natural product superstolide A: A role played by the lactone moiety.

    PubMed

    Qiu, Haibo; Qian, Shan; Head, Sarah A; Liu, Jun O; Jin, Zhendong

    2016-10-01

    Compound ZJ-101, a structurally simplified analog of the marine natural product superstolide A, was previously developed in our laboratory. In the subsequent structure-activity relationship study, a new analog ZJ-109 was designed and synthesized to probe the importance of the lactone moiety of the molecule by replacing the lactone in ZJ-101 with a lactam. The biological evaluation showed that ZJ-109 is about 8-12 times less active against cancer cells in vitro than ZJ-101, suggesting that the lactone moiety of the molecule is important for its anticancer activity. Copyright © 2016 Elsevier Ltd. All rights reserved.

  7. Technical Documentation and Legal Liability.

    ERIC Educational Resources Information Center

    Caher, John M.

    1995-01-01

    States that litigation over the interpretation and sufficiency of technical documentation is increasingly common as a number of suits have been filed in state and federal courts. Describes the case of "Martin versus Hacker," a recent case in which New York's highest court analyzed a technical writer's prose in the context of a lawsuit…

  8. Technical Support for Contaminated Sites

    EPA Science Inventory

    In 1987, the U.S. Environmental Protection Agency’s (EPA) Office of Research and Development (ORD), Office of Land and Emergency Management, and EPA Regional waste management offices established the Technical Support Project. The creation of the Technical Support Project enabled...

  9. Technical Support for Contaminated Sites

    EPA Science Inventory

    In 1987, the U.S. Environmental Protection Agency’s (EPA) Office of Research and Development (ORD), Office of Land and Emergency Management, and EPA Regional waste management offices established the Technical Support Project. The creation of the Technical Support Project enabled...

  10. Grid Interaction Technical Team Roadmap

    SciTech Connect

    2013-06-01

    The mission of the Grid Interaction Technical Team (GITT) is to support a transition scenario to large scale grid-connected vehicle charging with transformational technology, proof of concept and information dissemination. The GITT facilitates technical coordination and collaboration between vehicle-grid connectivity and communication activities among U.S. DRIVE government and industry partners.

  11. Technical Support for Contaminated Sites

    EPA Science Inventory

    In 1987, the U.S. Environmental Protection Agency’s (EPA) Office of Research and Development (ORD), Office of Land and Emergency Management, and EPA Regional waste management offices established the Technical Support Project. The creation of the Technical Support Project e...

  12. The 1996 NAEP Technical Report.

    ERIC Educational Resources Information Center

    Allen, Nancy L.; Carlson, James E.; Zelenak, Christine A.

    This report documents the design, administration, and data analysis procedure of the National Assessment of Education Progress (NAEP) for 1996. It indicates the technical decisions that were made and the rationale behind them. Detailed substantive findings are not presented in this report. These chapters provide technical information about the…

  13. Technical Documentation and Legal Liability.

    ERIC Educational Resources Information Center

    Caher, John M.

    1995-01-01

    States that litigation over the interpretation and sufficiency of technical documentation is increasingly common as a number of suits have been filed in state and federal courts. Describes the case of "Martin versus Hacker," a recent case in which New York's highest court analyzed a technical writer's prose in the context of a lawsuit…

  14. Hanford Site technical baseline database

    SciTech Connect

    Porter, P.E., Westinghouse Hanford

    1996-05-10

    This document includes a cassette tape that contains the Hanford specific files that make up the Hanford Site Technical Baseline Database as of May 10, 1996. The cassette tape also includes the delta files that delineate the differences between this revision and revision 3 (April 10, 1996) of the Hanford Site Technical Baseline Database.

  15. Scientific and Technical Document Database

    National Institute of Standards and Technology Data Gateway

    NIST Scientific and Technical Document Database (PC database for purchase)   The images in NIST Special Database 20 contain a very rich set of graphic elements from scientific and technical documents, such as graphs, tables, equations, two column text, maps, pictures, footnotes, annotations, and arrays of such elements.

  16. Technical Writing: The Real Needs.

    ERIC Educational Resources Information Center

    Sparrow, W. Keats

    To understand the specific differences between technical writing and ordinary writing, it is helpful to consider five definitions cited by W. Earl Britton: (1) technical writing deals with subject matter in science, engineering, and business; (2) it demands a specialized vocabulary, particularly of adjectives and nouns; (3) it involves a tightly…

  17. EDI and the Technical Communicator.

    ERIC Educational Resources Information Center

    Eiler, Mary Ann

    1994-01-01

    Assesses the role of technical communicators in electronic data interchange (EDI). Argues that, as experts in information design, human factors, instructional theory, and professional writing, technical communicators should be advocates of standard documentation protocols and should rethink the traditional concepts of "document" to…

  18. COMPASS Accelerator Design Technical Overview

    SciTech Connect

    Nanni, Emilio; Dolgashev, Valery; Tantawi, Sami; Neilson, Jeff

    2016-03-14

    This report is a survey of technical options for generating a MeV-class accelerator for space based science applications. The survey was performed focusing on the primary technical requirements of the accelerator in the context of a satellite environment with its unique challenges of limited electrical power (PE), thermal isolation, dimensions, payload requirement and electrical isolation.

  19. Technical Education for the Seventies.

    ERIC Educational Resources Information Center

    1969

    Presentations at the clinic focused on technical education programs under the Vocational Education Act of 1963 and the influence of the Vocational Education Amendments of 1968. The 12 presentations were grouped into three general subject areas. Four addresses discussed the emerging role of technical education, some suggestions for school-community…

  20. Cultural Influences on Technical Manuals.

    ERIC Educational Resources Information Center

    Warren, Thomas L.

    2002-01-01

    Discusses the cultural elements in developing a technical manual. Shows, through a comparison of two mythical cultures, how the manual will differ when organized for those two cultures. Considers the influences of culture on developing technical documents, specifically manuals. Concludes that the attitudes of a culture are significant factors in…

  1. Technical planning activity: Final report

    SciTech Connect

    Not Available

    1987-01-01

    In April 1985, the US Department of Energy's (DOE's) Office of Fusion Energy commissioned the Technical Planning Activity (TPA). The purpose of this activity was to develop a technical planning methodology and prepare technical plans in support of the strategic and policy framework of the Magnetic Fusion Program Plan issued by DOE in February 1985. Although this report represents the views of only the US magnetic fusion community, it is international in scope in the sense that the technical plans contained herein describe the full scope of the tasks that are prerequisites for the commercialization of fusion energy. The TPA has developed a well-structured methodology that includes detailed definitions of technical issues, definitions of program areas and elements, statements of research and development objectives, identification of key decision points and milestones, and descriptions of facility requirements.

  2. 7 CFR 1469.9 - Technical assistance.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 10 2010-01-01 2010-01-01 false Technical assistance. 1469.9 Section 1469.9... Provisions § 1469.9 Technical assistance. (a) NRCS may use the services of NRCS-approved or certified Technical Service Providers in performing its responsibilities for technical assistance. (b) Technical...

  3. FINAL TECHNICAL REPORT

    SciTech Connect

    STEFAN VASILE; ZHENG LI

    2010-06-17

    High-resolution tracking detectors based on Active Pixel Sensor (APS) have been valuable tools in Nuclear Physics and High-Energy Physics research, and have contributed to major discoveries. Their integration time, radiation length and readout rate is a limiting factor for the planed luminosity upgrades in nuclear and high-energy physics collider-based experiments. The goal of this program was to demonstrate and develop high-gain, high-resolution tracking detector arrays with faster readout, and shorter radiation length than APS arrays. These arrays may operate as direct charged particle detectors or as readouts of high resolution scintillating fiber arrays. During this program, we developed in CMOS large, high-resolution pixel sensor arrays with integrated readout, and reset at pixel level. Their intrinsic gain, high immunity to surface and moisture damage, will allow operating these detectors with minimal packaging/passivation requirements and will result in radiation length superior to APS. In Phase I, we designed and fabricated arrays with calorimetric output capable of sub-pixel resolution and sub-microsecond readout rate. The technical effort was dedicated to detector and readout structure development, performance verification, as well as to radiation damage and damage annealing.

  4. Final Technical Report

    SciTech Connect

    Stoessel, Chris

    2013-11-13

    This project developed a new high-performance R-10/high SHGC window design, reviewed market positioning and evaluated manufacturing solutions required for broad market adoption. The project objectives were accomplished by: identifying viable technical solutions based on modeling of modern and potential coating stacks and IGU designs; development of new coating material sets for HM thin film stacks, as well as improved HM IGU designs to accept multiple layers of HM films; matching promising new coating designs with new HM IGU designs to demonstrate performance gains; and, in cooperation with a window manufacturer, assess the potential for high-volume manufacturing and cost efficiency of a HM-based R-10 window with improved solar heat gain characteristics. A broad view of available materials and design options was applied to achieve the desired improvements. Gated engineering methodologies were employed to guide the development process from concept generation to a window demonstration. The project determined that a slightly de-rated window performance allows formulation of a path to achieve the desired cost reductions to support end consumer adoption.

  5. Final Technical Report

    SciTech Connect

    Frederick J. Carranti, P.E.

    2008-02-27

    During the contract period noted above, the Syracuse University Industrial Assessment Center conducted 97.5 assessment days for 98 different industrial clients. These assessments developed 818 assessment recommendations with an overall implementation rate of 51 % (AR’s). Total recommended dollar savings for the period was $17,386,758.00, with $8,893,212.00 actually implemented, for a dollar implementation rate of 57%. The Center employed a total of sixteen undergraduate interns throughout the contract period. Nine of these students stayed on at Syracuse University for graduate study with Center support; five students pursued graduate study at other universities. Ten of these students have, or will, accept professional positions in the energy consulting field. The Center has successfully engaged with a wide variety of professional and development organizations, including the Manufacturers Association of Central New York, The Central New York Technical Development Organization, (the local MEP), the New York State Energy Research and Development Authority, The New York Power Authority, the Onondaga County Citizens Energy Committee, and the New York State Center of Excellence on Indoor Environmental Systems.

  6. GEM Technical Design Report

    SciTech Connect

    Not Available

    1993-07-31

    The GEM collaboration was formed in June 1991 to develop a major detector for the SSC. The primary physics objectives of GEM are those central to the motivation for the SSC, to study high p{sub T} physics - exemplified by the search for Higgs bosons - and to search for new physics beyond the standard model. The authors present in this Technical Design Report (TDR) a detector with broad capabilities for the discovery and subsequent study of electroweak symmetry breaking, the origin of mass and flavor, and other physics requiring precise measurements of gammas, electrons, and muons - hence the name, GEM. In addition, as a design goal, they have taken care to provide the robustness needed to do the physics that requires high luminosity. Finally, good coverage and hermeticity allow the detection of missing transverse energy, E{sub T}. The GEM design emphasizes clean identification and high resolution measurement of the primary physics signatures for high p{sub T} physics. The approach is to make precise energy measurements that maximize the sensitivity to rare narrow resonances, to detect the elementary interaction products (quarks, leptons, and photons), and to build in the features required to reduce backgrounds.

  7. Final Technical Report

    SciTech Connect

    Dmitriy Y. Anistratov; Marvin L. Adams; Todd S. Palmer; Kord S. Smith; Kevin Clarno; Hikaru Hiruta; Razvan Nes

    2003-08-04

    OAK B202 Final Technical Report. The present generation of reactor analysis methods uses few-group nodal diffusion approximations to calculate full-core eigenvalues and power distributions. The cross sections, diffusion coefficients, and discontinuity factors (collectively called ''group constants'') in the nodal diffusion equations are parameterized as functions of many variables, ranging from the obvious (temperature, boron concentration, etc.) to the more obscure (spectral index, moderator temperature history, etc.). These group constants, and their variations as functions of the many variables, are calculated by assembly-level transport codes. The current methodology has two main weaknesses that this project addressed. The first weakness is the diffusion approximation in the full-core calculation; this can be significantly inaccurate at interfaces between different assemblies. This project used the nodal diffusion framework to implement nodal quasidiffusion equations, which can capture transport effects to an arbitrary degree of accuracy. The second weakness is in the parameterization of the group constants; current models do not always perform well, especially at interfaces between unlike assemblies. The project developed a theoretical foundation for parameterization and homogenization models and used that theory to devise improved models. The new models were extended to tabulate information that the nodal quasidiffusion equations can use to capture transport effects in full-core calculations.

  8. Engineering Technical Review Planning Briefing

    NASA Technical Reports Server (NTRS)

    Gardner, Terrie

    2012-01-01

    The general topics covered in the engineering technical planning briefing are 1) overviews of NASA, Marshall Space Flight Center (MSFC), and Engineering, 2) the NASA Systems Engineering(SE) Engine and its implementation , 3) the NASA Project Life Cycle, 4) MSFC Technical Management Branch Services in relation to the SE Engine and the Project Life Cycle , 5) Technical Reviews, 6) NASA Human Factor Design Guidance , and 7) the MSFC Human Factors Team. The engineering technical review portion of the presentation is the primary focus of the overall presentation and will address the definition of a design review, execution guidance, the essential stages of a technical review, and the overall review planning life cycle. Examples of a technical review plan content, review approaches, review schedules, and the review process will be provided and discussed. The human factors portion of the presentation will focus on the NASA guidance for human factors. Human factors definition, categories, design guidance, and human factor specialist roles will be addressed. In addition, the NASA Systems Engineering Engine description, definition, and application will be reviewed as background leading into the NASA Project Life Cycle Overview and technical review planning discussion.

  9. Quantum mechanics models of the methanol dimer: O-H…O hydrogen bonds of ß-D-glucose moieties from crystallographic data.

    USDA-ARS?s Scientific Manuscript database

    In this study, a survey of the Cambridge Crystal Structure Database for all donor-acceptor interactions in ß-D-glucose moieties was performed to examine the similarities and differences among the different hydroxyl groups and ether oxygen atoms that participate in hydrogen bonds. Comparable behavior...

  10. Surface segregation of fluorinated moieties on poly(methyl methacrylate-ran-2-perfluorooctylethyl methacrylate) films during film formation: Entropic or enthalpic influences.

    PubMed

    Ye, Xiuyun; Zuo, Biao; Deng, Mao; Hei, Yanlin; Ni, Huagang; Lu, Xiaolin; Wang, Xinping

    2010-09-01

    The effects of solvents, fluorinated monomer content and film-formation methods on the surface structures of random copolymers composed of methyl methacrylate (MMA) and 2-perfluorooctylethyl methacrylate (FMA) were investigated by contact angle goniometry, X-ray photoelectron spectroscopy, sum frequency generation (SFG) vibrational spectroscopy and surface tension measurement. It is found that, with cyclohexanone as the solvent, there is a critical FMA content of 9mol%, below which the copolymer films by spin coating have a more surface segregation extent of fluorinated moieties than those by solution casting; above which the copolymer films by solution casting have a more surface segregation extent of fluorinated moieties than those by spin coating. However, with toluene as solvent, the critical FMA content lowers down to 3mol%. We believe that the solvent nature and the content of fluorinated moieties in the random copolymer have the great effect because the combined effect of these two factors can determine the random copolymer chain conformations and their thermodynamic dominating factors in the solution and at the solution-air interface. A thermodynamic analysis combining the entropic and enthalpic effects is suggested to explain the observed phenomenon. This research is believed to obtain an enhanced understanding of the surface formation mechanism of the polymer films and thus demonstrate how to promote the segregation of fluorinated moieties at the polymer film surfaces.

  11. Polymer composite electrolytes having core-shell silica fillers with anion-trapping boron moiety in the shell layer for all-solid-state lithium-ion batteries.

    PubMed

    Shim, Jimin; Kim, Dong-Gyun; Kim, Hee Joong; Lee, Jin Hong; Lee, Jong-Chan

    2015-04-15

    Core-shell silica particles with ion-conducting poly(ethylene glycol) and anion-trapping boron moiety in the shell layer were prepared to be used as fillers for polymer composite electrolytes based on organic/inorganic hybrid branched copolymer as polymer matrix for all-solid-state lithium-ion battery applications. The core-shell silica particles were found to improve mechanical strength and thermal stability of the polymer matrix and poly(ethylene glycol) and boron moiety in the shell layer increase compatibility between filler and polymer matrix. Furthermore, boron moiety in the shell layer increases both ionic conductivity and lithium transference number of the polymer matrix because lithium salt can be more easily dissociated by the anion-trapping boron. Interfacial compatibility with lithium metal anode is also improved because well-dispersed silica particles serve as protective layer against interfacial side reactions. As a result, all-solid-state battery performance was found to be enhanced when the copolymer having core-shell silica particles with the boron moiety was used as solid polymer electrolyte.

  12. 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.

  13. 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.

  14. 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.

  15. Arginine 485 of human serum albumin interacts with the benzophenone moiety of ketoprofen in the binding pocket of subdomain III A and III B.

    PubMed

    Kaneko, K; Chuang, V T G; Ito, T; Suenaga, A; Watanabe, H; Maruyama, T; Otagiri, M

    2012-05-01

    Arylpropionic acid nonsteroidal anti-inflammatory drusg (NSAIDs) primarily bind to subdomain III A (site II) of human serum albumin (HSA). Ketoprofen (KP), an arylpropionic acid that contains a photoreactive benzophenone moiety, was used to photolabel the binding region of site II. LC/Q-TOF mass spectrometry determination revealed that R485 was the amino acid residue that formed covalent adduct with the benzophenone moiety of KP. Point mutation of arginine 485 to alanine showed a slight decrease in the overall binding percentage of KP when compared to that of native HSA. The induced circular dichroism spectral data of KP with both R485A and native albumin confirmed the photolabeling findings. Interestingly, an increase in the extent of [14C]KP covalent adduct formation with the 11.6 kDa peptide derived from subdomain IIB-IIIA was observed for R485A. In contrast, mutation of arginine 410 caused a significant reduction of binding percentage, confirming the importance of this residue in high affinity binding of arylpropionic acid derivatives. This may indicate that while KP's carboxylate interacts electrostatically with arginine 410, the benzophenone moiety may have swung away from helix 6 in the absence of arginine 485. In this study, photolabeling of native and mutants albumins, R485A and R410C with [14C]KP confirmed that R485 involved in the non-electrostatic interaction with the benzophenone moiety of KP, but not vital to hold KP in the binding pocket of subdomain IIIA.

  16. A New Metabolite with a unique 4-pyranone-ylactam-1,4-thiazine moiety from a Hawaiian-plant associated fungus

    USDA-ARS?s Scientific Manuscript database

    An endophytic fungus Paraphaeosphaeria neglecta FT462 isolated from the Hawaiian-plant Lycopodiella cernua (L.) Pic. Serm produced one unusual compound (1, paraphaeosphaeride A) with the 4-pyranone-'-lactam-1,4-thiazine moiety, along with two new compounds (2 and 3, paraphaeosphaerides B and C, resp...

  17. 78 FR 65689 - Technical Mapping Advisory Council

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-11-01

    ... SECURITY Federal Emergency Management Agency Technical Mapping Advisory Council AGENCY: Federal Emergency... Emergency Management Agency's Technical Mapping Advisory Council. SUMMARY: The Federal Emergency Management Agency (FEMA) is requesting qualified individuals interested in serving on the Technical Mapping Advisory...

  18. Australia: A New Technical Teacher College

    ERIC Educational Resources Information Center

    Senior, R. L.

    1969-01-01

    A new technical teacher college will open its doors in Hawthorn, Victoria, in January 1970. R.L. Senior, Inspector of Technical Schools, describes the development of technical teacher training in the State. (Editor)

  19. Technical Standards Products Informing NASA Quality Practices

    NASA Technical Reports Server (NTRS)

    Oberhettinger, David

    2006-01-01

    This viewgraph presentation includes formal definitions of standards (external and internal), as well as discussions of the importance of standards to NASA, current technical standards issues, the NASA technical standards program, and provides technical standards resources.

  20. Technical Standards Products Informing NASA Quality Practices

    NASA Technical Reports Server (NTRS)

    Oberhettinger, David

    2006-01-01

    This viewgraph presentation includes formal definitions of standards (external and internal), as well as discussions of the importance of standards to NASA, current technical standards issues, the NASA technical standards program, and provides technical standards resources.

  1. Industrial Hardening: 1980 Technical Report.

    DTIC Science & Technology

    1981-06-01

    AD-AI02 621 SCIENTIFIC SERVICE INC REDWOOD CITY CA F/6 15/3 INDUSTRIAL HARDENING: 1980 TECHNICAL REPORT . (U) JUN 81 J V ZACCOR, C WILTON. R D BERNARD...INDUSTRIAL HARDENING. 1980 TECHNICAL REPORT zFINAL REPORT OL ELTC : -. brCc -i ’ Approved for public release; Contract No. EMW-C-0154 distribution...TYPE Of REPORT & PERIOD COVERED INDUSTRIAL HARDENING: 198k TECHNICAL REPORT , Final Ppoe t *PEg 8’Wo-C"EPT UMBER 7. AUTHOR(@) S. CONTRACT OR GRANT

  2. Final Environmental Planning Technical Report

    DTIC Science & Technology

    1984-01-01

    AD-A267 225e i Department of the Air Force FINAL ENVIRONMENTAL JUL 1993 PLANNINGU• TECHNICAL REPORT _____________-_--_ AIR QUALITY P+prpoT d kr ptu...2922 JUL 16 󈨡 9:31 703 614 -1572 PAGE. 002’ FINAL ENVIRONMENTAL PLANNING TECHNICAL REPORT AIR QUALITY January 1984 PREFACE The President has directed...Matrix 3-33 vi 1.0 INTRODUCTION 1.0 INTRODUCTION This final environmental planning technical report (EPTR) is a companion document to the air quality

  3. Engineering directorate technical facilities catalog

    NASA Technical Reports Server (NTRS)

    Maloy, Joseph E.

    1993-01-01

    The Engineering Directorate Technical Facilities Catalog is designed to provide an overview of the technical facilities available within the Engineering Directorate at the National Aeronautics and Space Administration (NASA), Lyndon B. Johnson Space Center (JSC) in Houston, Texas. The combined capabilities of these engineering facilities are essential elements of overall JSC capabilities required to manage and perform major NASA engineering programs. The facilities are grouped in the text by chapter according to the JSC division responsible for operation of the facility. This catalog updates the facility descriptions for the JSC Engineering Directorate Technical Facilities Catalog, JSC 19295 (August 1989), and supersedes the Engineering Directorate, Principle test and Development Facilities, JSC, 19962 (November 1984).

  4. The Independent Technical Analysis Process

    SciTech Connect

    Duberstein, Corey A.; Ham, Kenneth D.; Dauble, Dennis D.; Johnson, Gary E.

    2007-04-13

    The Bonneville Power Administration (BPA) contracted with the Pacific Northwest National Laboratory (PNNL) to provide technical analytical support for system-wide fish passage information (BPA Project No. 2006-010-00). The goal of this project was to produce rigorous technical analysis products using independent analysts and anonymous peer reviewers. In the past, regional parties have interacted with a single entity, the Fish Passage Center to access the data, analyses, and coordination related to fish passage. This project provided an independent technical source for non-routine fish passage analyses while allowing routine support functions to be performed by other well-qualified entities.

  5. Inhibition studies of bacterial, fungal and protozoan β-class carbonic anhydrases with Schiff bases incorporating sulfonamide moieties.

    PubMed

    Ceruso, Mariangela; Carta, Fabrizio; Osman, Sameh M; Alothman, Zeid; Monti, Simona Maria; Supuran, Claudiu T

    2015-08-01

    A series of new Schiff bases derived from sulfanilamide, 3-fluorosulfanilamide or 4-(2-aminoethyl)-benzenesulfonamide containing either a hydrophobic or a hydrophilic tail, have been investigated as inhibitors of three β-carbonic anhydrases (CA, EC 4.2.1.1) from three different microorganisms. Their antifungal, antibacterial and antiprotozoan activities have been determined against the pathogenic fungus Cryptococcus neoformans, the bacterial pathogen Brucella suis and the protozoan parasite Leishmania donovani chagasi, responsible for Leishmaniasis. The results of these inhibition studies show that all three enzymes were efficiently inhibited by the Schiff base sulfonamides with KI values in the nanomolar or submicromolar range, depending on the nature of the tail, coming from the aryl/heteroaryl moiety present in the starting aldehyde employed in the synthesis. Furthermore, the compounds hereby investigated revealed high β-CAs selectivity over the ubiquitous, physiologically relevant and off-target human isoforms (CA I and II) and to be more potent as antifungal and antibacterial than as antiprotozoan potential drugs. Copyright © 2015 Elsevier Ltd. All rights reserved.

  6. Synthesis, characterization, and in vitro evaluation and in silico molecular docking of thiourea derivatives incorporating 4-(trifluoromethyl)phenyl moiety

    NASA Astrophysics Data System (ADS)

    Qiao, Lei; Huang, Jie; Hu, Wei; Zhang, Yu; Guo, Jiajia; Cao, Wenli; Miao, Kanghua; Qin, Baofu; Song, Jirong

    2017-07-01

    A series of acyl thiourea derivatives bearing 4-(trifluoromethyl)phenyl moiety (7 compounds) has been synthesized and characterized by FT-IR, 1H and 13C NMR spectroscopy and elemental analyses. The molecular structure of five compounds (2, 4, 5, 6 and 7) was determined by single crystal X-ray diffraction analysis. The crystal structures revealed that the carbonyl thiourea units in all determined compounds are mostly planar due in part to the formation of intramolecular Nsbnd H⋯Odbnd C and Csbnd H⋯Sdbnd C hydrogen bonds that form two S (6) rings. The intermolecular contacts of five crystal structures have been preformed based on the Hirshfeld surface and their associated 2D fingerprint plots. All the synthesized compounds were preliminarily screened for their in vitro anti-fungal activity. Especially, compounds 4, 5 and 6 showed a good anti-fungal activity for four different kinds of fungi. Furthermore, all prepared thiourea derivatives were screened for antioxidant potential activity by DPPH free radical scavenging and the excellent activity were found compounds 5 and 6 with the IC50 value of 191.75 μg/mL and 189.75 μg/mL, respectively. In silico molecular docking studies were performed to screen the thiourea derivatives against heat shock protein HSP90.

  7. Electropolymerization of a calix[4]arene modified by N-substituted pyrrole moieties. New sensitive layer for ionic electrochemical detection

    NASA Astrophysics Data System (ADS)

    Buffenoir, A.; Bidan, G.

    1998-06-01

    A calix[4]arene modified by grafting N-substituted pyrrole moieties at the upper rim was synthetised. Electropolymerisation of this new calix[4]arene in a Bu4NClO4 (10-1 M) - CH3CN solution is described. The obtained film presents a rather stable electroactivity to electrochemical cycling but its growing is limited to a few monolayers. It's the first example of homopolymerisation of a calix[4]arene modified by electropolymerisable monomers. Un calix[4]arène modifié sur sa couronne supérieure par des pyrroles N-substitués a été synthétisé. Son électropolymérisation en milieu Bu4NClO4 (10-1 M) - CH3CN par balayage de potentiels est décrite. Le film obtenu présente une électroactivité assez stable au cyclage électrochimique mais sa croissance est limitée à quelques monocouches. C'est le premier exemple d'homopolymérisation d'un calix[4]arène modifié par des monomères électropolymérisables.

  8. The lipid moiety of haemozoin (Malaria Pigment) and P. falciparum parasitised red blood cells bind synthetic and native endothelin-1.

    PubMed

    Basilico, Nicoletta; Parapini, Silvia; Sisto, Francesca; Omodeo-Salè, Fausta; Coghi, Paolo; Ravagnani, Fernando; Olliaro, Piero; Taramelli, Donatella

    2010-01-01

    Endothelin1 (ET-1) is a 21-amino acid peptide produced by the vascular endothelium under hypoxia, that acts locally as regulator of vascular tone and inflammation. The role of ET-1 in Plasmodium falciparum malaria is unknown, although tissue hypoxia is frequent as a result of the cytoadherence of parasitized red blood cell (pRBC) to the microvasculature. Here, we show that both synthetic and endothelial-derived ET-1 are removed by parasitized RBC (D10 and W2 strains, chloroquine sensitive, and resistant, resp.) and native haemozoin (HZ, malaria pigment), but not by normal RBC, delipidized HZ, or synthetic beta-haematin (BH). The effect is dose dependent, selective for ET-1, but not for its precursor, big ET-1, and not due to the proteolysis of ET-1. The results indicate that ET-1 binds to the lipids moiety of HZ and membranes of infected RBCs. These findings may help understanding the consequences of parasite sequestration in severe malaria.

  9. The Lipid Moiety of Haemozoin (Malaria Pigment) and P. falciparum Parasitised Red Blood Cells Bind Synthetic and Native Endothelin-1

    PubMed Central

    Basilico, Nicoletta; Parapini, Silvia; Sisto, Francesca; Omodeo-Salè, Fausta; Coghi, Paolo; Ravagnani, Fernando; Olliaro, Piero; Taramelli, Donatella

    2010-01-01

    Endothelin1 (ET-1) is a 21-amino acid peptide produced by the vascular endothelium under hypoxia, that acts locally as regulator of vascular tone and inflammation. The role of ET-1 in Plasmodium falciparum malaria is unknown, although tissue hypoxia is frequent as a result of the cytoadherence of parasitized red blood cell (pRBC) to the microvasculature. Here, we show that both synthetic and endothelial-derived ET-1 are removed by parasitized RBC (D10 and W2 strains, chloroquine sensitive, and resistant, resp.) and native haemozoin (HZ, malaria pigment), but not by normal RBC, delipidized HZ, or synthetic beta-haematin (BH). The effect is dose dependent, selective for ET-1, but not for its precursor, big ET-1, and not due to the proteolysis of ET-1. The results indicate that ET-1 binds to the lipids moiety of HZ and membranes of infected RBCs. These findings may help understanding the consequences of parasite sequestration in severe malaria. PMID:20204072

  10. Syntheses of D-A-A Type Small Molecular Donor Materials Having Various Electron Accepting Moiety for Organic Photovoltaic Application.

    PubMed

    Kim, Nahyeon; Park, Sangman; Lee, Myong-Hoon; Lee, Jaemin; Lee, Changjin; Yoon, Sung Cheol

    2016-03-01

    Small molecular donor, DTDCTB achieved a high power conversion efficiency (PCE) value of 6.6 ± 0.2% in vacuum-deposited planar mixed heterojunction (PMHJ) structure. However, the same material just recorded PCE of 0.34% in solution processed small molecule based bulk heterjunction (BHJ) organic photovoltaic cells. For the improvement of organic photovoltaic cells (OPVs), In this study, we designed and synthesized several D-A-A (donor-acceptor-acceptor) type molecular electron donating materials. Ditolylaminothienyl moiety as an electron donating group connected to 1,2,5-benzothiadiazole as a conjugated electron accepting unit, simultaneously with an electron accepting terminal group such as cyano alkyl acetate and N-alkyl rhodanine. The thermal, photophysical, and electrochemical properties of prepared small molecules were investigated by DSC, UV/Vis spectroscopy and Cyclic Voltametry, respectively. As a result, 0.89% of PCE can be obtained from OPV using a mixture of DTATBTER and PCBM as an active layer with a Voc of 0.87 V, a Jsc of 3.20 mA/cm2, and a fill factor of 31.9%.

  11. Tuning the Electrical Memory Behavior from Nonvolatile to Volatile in Functional Copolyimides Bearing Varied Fluorene and Pyrene Moieties

    NASA Astrophysics Data System (ADS)

    Jia, Nanfang; Qi, Shengli; Tian, Guofeng; Wang, Xiaodong; Wu, Dezhen

    2017-04-01

    For producing polymer based electronics with good memory behavior, a series of functional copolyimides were designed and synthesized in this work by copolymerizing 3,3',4,4'-diphenylsulfonetetracarboxylic dianhydride (DSDA) with (9,9'-bis(4-aminophenyl)fluorene) (BAPF) and N, N-bis(4-aminophenyl) aminopyrene (DAPAP) diamines. The synthesized copolyimides DSDA/(DAPAP/BAPF) were denoted as coPI-DAPAP x ( x = 100, 50, 20, 10, 5, 1, 0), where x% represents the molar fraction of the DAPAP unit in the diamines. Characterization results indicate that the coPI-DAPAP x exhibits tunable electrical switching behaviors from write once read many times (WORM, nonvolatile, coPI-DAPAP100, coPI-DAPAP50, coPI-DAPAP20, coPI-DAPAP10) to the static random access memory (SRAM, volatile, coPI-DAPAP5, coPI-DAPAP1) with the variation of the DAPAP content. Optical and electrochemical characterization show gradually decreasing highest occupied molecular orbital levels and enlarged energy gap with the decrease of the DAPAP moiety, suggesting decreasing charge-transfer effect in the copolyimides, which can account for the observed WORM-SRAM memory conversion. Meanwhile, the charge transfer process was elucidated by quantum chemical calculation at B3LYP/6-31G(d) theory level. This work shows the effect of electron donor content on the memory behavior of polymer electronic materials.

  12. Origins of natural gases from marine strata in Northeastern Sichuan Basin (China) from carbon molecular moieties and isotopic data

    NASA Astrophysics Data System (ADS)

    Wang, Yunpeng; Zhao, Changyi; Wang, Hongjun; Wang, Zhaoyun; Wang, Zecheng

    2013-03-01

    To determine the origin, maturity, formation mechanism and secondary process of marine natural gases in Northeastern Sichuan area, molecular moieties and carbon isotopic data of the Carboniferous and Triassic gases have been analyzed. Typical samples of marine gas precursors including low-maturity kerogen, dispersed liquid hydrocarbons (DLHs) in source rocks, residual kerogen and oil have been examined in a closed system, and several published geochemical diagrams of gas origins have been calibrated by using laboratory data. Results show that both Carboniferous and Triassic gases in the study area have a thermogenic origin. Migration leads to stronger compositional and weak isotopic fractionation, and is path dependent. Carboniferous gases and low-H2S gases are mainly formed by secondary cracking of oil, whereas high-H2S gases are clearly related to the TSR (Thermal Sulfate Reduction) process. Gases in NE Sichuan show a mixture of heavy (13C-enriched) methane in comparison to the lower maturated ethane of Triassic gas samples, suggesting a similar source and maturity for ethane and propane of Carboniferous gases, and a mixture of heavy ethane to the propane for Triassic gases. Based on the data plotted in the diagram of Chung et al. (1988), the residual kerogen from Silurian marine shale and palaeo oil reservoirs are the main source for Carboniferous gases, and that the residual kerogen from Silurian and Permian marine rocks and Permian paleao oil reservoirs constitute the principal source of Triassic gases.

  13. Influence of Galloyl Moiety in Interaction of Epicatechin with Bovine Serum Albumin: A Spectroscopic and Thermodynamic Characterization

    PubMed Central

    Pal, Sandip; Saha, Chabita; Hossain, Maidul; Dey, Subrata Kumar; Kumar, Gopinatha Suresh

    2012-01-01

    The health benefits stemming from green tea are well known, but the exact mechanism of its biological activity is not elucidated. Epicatechin (EC) and epicatechin gallate (ECG) are two dietary catechins ubiquitously present in green tea. Serum albumins functionally carry these catechins through the circulatory system and eliminate reactive oxygen species (ROS) induced injury. In the present study ECG is observed to have higher antioxidant activity; which is attributed to the presence of galloyl moiety. The binding affinity of these catechins to bovine serum albumin (BSA) will govern the efficacy of their biological activity. EC and ECG bind with BSA with binding constants 1.0×106 M−1 and 6.6×107 M−1, respectively. Changes in secondary structure of BSA on interaction with EC and ECG have been identified by circular dichroism (CD) and Fourier transform infrared (FT-IR) spectroscopy. Thermodynamic characterization reveals the binding process to be exothermic, spontaneous and entropy driven. Mixed binding forces (hydrophobic, electrostatic and hydrogen bonding) exist between ECG and BSA. Binding site for EC is primarily site-II in sub-domain IIIA of BSA and for ECG; it is site-I in sub-domain IIA. ECG with its high antioxidant activity accompanied by high affinity for BSA could be a model in drug designing. PMID:22916242

  14. Synthesis and Antimicrobial Evaluation of Some Novel Thiazole, Pyridone, Pyrazole, Chromene, Hydrazone Derivatives Bearing a Biologically Active Sulfonamide Moiety

    PubMed Central

    Darwish, Elham S.; Abdel Fattah, Azza M.; Attaby, Fawzy A.; Al-Shayea, Oqba N.

    2014-01-01

    This study aimed for the synthesis of new heterocyclic compounds incorporating sulfamoyl moiety suitable for use as antimicrobial agents via a versatile, readily accessible N-[4-(aminosulfonyl)phenyl]-2-cyanoacetamide (3). The 2-pyridone derivatives were obtained via reaction of cyanoacetamide with acetylacetone or arylidenes malononitrile. Cycloaddition reaction of cyanoacetamide with salicyaldehyde furnished chromene derivatives. Diazotization of 3 with the desired diazonium chloride gave the hydrazone derivatives 13a–e. Also, the reactivity of the hydrazone towards hydrazine hydrate to give Pyrazole derivatives was studied. In addition, treatment of 3 with elemental sulfur and phenyl isothiocyanate or malononitrile furnished thiazole and thiophene derivatives respectively. Reaction of 3 with phenyl isothiocyanate and KOH in DMF afforded the intermediate salt 17 which reacted in situ with 3-(2-bromoacetyl)-2H-chromen-2-one and methyl iodide afforded the thiazole and ketene N,S-acetal derivatives respectively. Finally, reaction of 3 with carbon disulfide and 1,3-dibromopropane afforded the N-[4-(aminosulfonyl) phenyl]-2-cyano-2-(1,3-dithian-2-ylidene)acetamide product 22. All newly synthesized compounds were elucidated by considering the data of both elemental and spectral analysis. The compounds were evaluated for both their in vitro antibacterial and antifungal activities and showed promising results. PMID:24445259

  15. Syntheses, crystal structures, and water adsorption behaviors of jungle-gym-type porous coordination polymers containing nitro moieties

    NASA Astrophysics Data System (ADS)

    Uemura, Kazuhiro; Onishi, Fumiaki; Yamasaki, Yukari; Kita, Hidetoshi

    2009-10-01

    NO 2 containing dicarboxylate bridging ligands, nitroterephthalate (bdc-NO 2) and 2,5-dinitroterephthalate (bdc-(NO 2) 2), afford porous coordination polymers, {[Zn 2(bdc-NO 2) 2(dabco)]· solvents} n ( 2⊃ solvents) and {[Zn 2(bdc-(NO 2) 2) 2(dabco)]· solvents} n ( 3⊃ solvents). Both compounds form jungle-gym-type regularities, where a 2D square grid composed of dinuclear Zn 2 units and dicarboxylate ligands is bridged by dabco molecules to extend the 2D layers into a 3D structure. In 2⊃ solvents and 3⊃ solvents, a rectangle pore surrounded by eight Zn 2 corners contains two and four NO 2 moieties, respectively. Thermal gravimetry (TG) and X-ray powder diffraction (XRPD) measurements reveal that both compounds maintain the frameworks regularities without guest molecules and with solvents such as MeOH, EtOH, i-PrOH, and Me 2CO. Adsorption measurements reveal that dried 2 and 3 adsorb H 2O molecules to be {[Zn 2(bdc-NO 2) 2(dabco)]·4H 2O} n ( 2⊃4H 2O) and {[Zn 2(bdc-(NO 2) 2) 2(dabco)]·6H 2O} n ( 3⊃6H 2O), showing the pore hydrophilicity enhancement caused by NO 2 group introduction.

  16. Design, synthesis and biological evaluation of novel nicotinamide derivatives bearing a substituted pyrazole moiety as potential SDH inhibitors.

    PubMed

    Lv, Xian-Hai; Ren, Zi-Li; Liu, Peng; Li, Bing-Xin; Li, Qing-Shan; Chu, Ming-Jie; Cao, Hai-Qun

    2017-08-01

    Succinate dehydrogenase (SDH) plays an important role in the Krebs cycle, which is considered as an attractive target for development of succinate dehydrogenase inhibitors (SDHIs) based on antifungal agents. Thus, in order to discover novel molecules with high antifungal activities, SDH as the target for a series of novel nicotinamide derivatives bearing substituted pyrazole moieties were designed and synthesised via a one-pot reaction. The biological assay data showed that compound 3 l displayed the most potent antifungal activity with EC50 values of 33.5 and 21.4 µm against Helminthosporium maydis and Rhizoctonia cerealis, respectively. Moreover, 3 l exhibited the best inhibitory ability against SDH enzymes. The results of docking simulation showed that 3 l was deeply embedded into the SDH binding pocket, and the binding model was stabilised by a cation-π interaction with Arg 43, Tyr 58 and an H-bond with Trp 173. The study suggests that the pyrazole nicotinamide derivative 3 l may serve as a potential SDHI that can be used as a novel antifungal agent, and provides valuable clues for the further design and optimisation of SDH inhibitors. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

  17. Activation of DNA strand exchange by cationic comb-type copolymers: effect of cationic moieties of the copolymers

    PubMed Central

    Choi, Sung Won; Kano, Arihiro; Maruyama, Atsushi

    2008-01-01

    We have previously reported that poly(l-lysine)-graft-dextran cationic comb-type copolymers accelerate strand exchange reaction between duplex DNA and its complementary single strand by >4 orders of magnitude, while stabilizing duplex. However, the stabilization of the duplex is considered principally unfavourable for the accelerating activity since the strand exchange reaction requires, at least, partial melting of the initial duplex. Here we report the effects of different cationic moieties of cationic comb-type copolymers on the accelerating activity. The copolymer having guanidino groups exhibited markedly higher accelerating effect on strand exchange reactions than that having primary amino groups. The high accelerating effect of the former is considered to be due to its lower stabilizing effect on duplex DNA, resulting from its increased affinity to single-stranded DNA. The difference in affinity was clearly demonstrated by a fluorescence correlation spectroscopy study; the interaction of the former with single-stranded DNA still remained high even at 1 M NaCl, while that of the latter completely disappeared. These results suggest that some modes of interactions, such as hydrogen bonding, other than electrostatic interactions between the copolymers having guanidino groups and DNAs may be involved in strand exchange activation. PMID:18033803

  18. Novel Quinazoline Derivatives Bearing Various 4-Aniline Moieties as Potent EGFR Inhibitors with Enhanced Activity Against NSCLC Cell Lines.

    PubMed

    Wang, Changyan; Sun, Yajun; Zhu, Xingqi; Wu, Bin; Wang, Qiao; Zhen, Yuhong; Shu, Xiaohong; Liu, Kexin; Zhou, Youwen; Ma, Xiaodong

    2016-04-01

    A class of novel quinazoline derivatives bearing various C-4 aniline moieties was synthesized and biologically evaluated as potent epidermal growth factor receptor (EGFR) inhibitors for intervention of non-small-cell lung cancer (NSCLC). Most of these inhibitors are comparable to gefitinib in inhibiting these cancer cell lines, and several of them even displayed superior inhibitory activity. In particular, analogue 5b with an IC50 of 0.10 μm against the EGFR wild-type A431 cells and 5c with an IC50 of 0.001 μm against the gefitinib-sensitive HCC827 cells (EGFR del E746-A750) was identified as highly active EGFR inhibitors. It was also significant that the discovered analogue 2f, not only has high potency against the gefitinib-sensitive cells (IC50 = 0.031 μm), but also possesses remarkably improved activity against the gefitinib-resistant cells. In addition, the enzymatic assays and the Western blot analysis for evaluating the effects of the typical inhibitors indicated that these molecules strongly interfere with the EGFR target.

  19. 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.

  20. Ultrasound-aided formation of gold nanoparticles on multi-walled carbon nanotubes functionalized with mercaptobenzene moieties.

    PubMed

    Park, Gle; Lee, Kyung G; Lee, Seok Jae; Park, Tae Jung; Wi, Ringbok; Wang, Kye Won; Kim, Do Hyun

    2011-07-01

    A hybrid of multi-walled carbon nanotube (MWCNT) and gold nanoparticle (Au NP) was prepared under ultrasound irradiation. The approach starts with the functionalization of the walls of MWCNTs with mercaptobenzene moieties for the subsequent immobilization of Au NPs. From the Raman spectra, mercaptobenzene was proven to exist on the MWCNTs. Gold ions were added to the aqueous dispersion of functionalized MWCNTs (f-MWCNTs), and were reduced with the aid of ultrasound and ammonium hydroxide. The reduced gold nanoparticles were examined from the TEM images. Au NPs adhered specifically on the thiol groups of mercaptobenzene to be deposited uniformly on the outer walls of the f-MWCNTs. The application of ultrasound led to a high yield of MWCNT-Au nanocomposites and to the dense distribution of the Au NPs. Moreover, the synthesis reaction rate of the hybrid was considerably enhanced relative to synthesis with mechanical agitation. Through an adsorption test using gold-binding-peptide-(GBP)-modified biomolecules, the hybrid's potential for biological diagnosis was verified.