Science.gov

Sample records for osservazioni di mercurio

  1. Osservazioni di Mercurio nel 1997.

    NASA Astrophysics Data System (ADS)

    Giuntoli, M.

    1999-08-01

    The observations of Mercury received by the UAI Planet Section during 1997 are analyzed. Nine observers contributed 60 report forms, mainly concerning the January, April and July elongations of the planet. Several disk markings were detected, as well as bright cusps. Visual phase estimates showed a reverse Schroeter effect.

  2. Osservazioni di Urano e Nettuno nel 2001

    NASA Astrophysics Data System (ADS)

    Carbognani, Albino

    2002-09-01

    The observations of Uranus and Neptune collected by the UAI Planet Section during the year 2001 are analysed. The Uranus disk in some occasion had presented a bright eccentric zone. The different colours of the border probably is an effect of atmospheric refraction. The Neptune disk was featureless. The methan band in the spectra of both planets was registered at different time but no changes were observed. Some indications for the next opposition of remote planets are given.

  3. Osservazioni dell'eclissi penombrale di Luna

    NASA Astrophysics Data System (ADS)

    Sigismondi, Costantino

    2016-05-01

    The penumbral lunar eclipses equilibrate the probability of occurrence of solar and lunar eclipses over several years, but they are often neglected in the media and in the observations because of the difficulty of their identification due to the high luminosity of the full Moon. Three methods are presented to reduce this luminosity and to detect the penumbral phase of the lunar eclipse: the reflection on glass and water, the double polarizer and the short exposure photographs with 400 and 800 ISO and 1/500s of pose.

  4. Il transito di Mercurio del 15 novembre 1999.

    NASA Astrophysics Data System (ADS)

    Carbognani, A.

    2000-02-01

    The 1999 November 15th transit of Mercury was observed. After a brief introduction to the transits of inferior planets, results of visual observation with a small refractor are described. A comparison between observed and computed times of contacts is made. A light aureole around Mercury was observed, no black-drop effect was noted.

  5. Desentrañar los secretos de Mercurio - Duration: 31 seconds.

    NASA Video Gallery

    De todos los planetas rocosos, Mercurio es el más pequeño y denso, el que posee la superficie más antigua y el que tiene las variaciones diarias de temperatura más amplias. También es el menos expl...

  6. Calibrazioni a terra e prestazioni in volo di spettrometri ad immagine nel visibile e nel vicino infrarosso per l'esplorazione planetaria

    NASA Astrophysics Data System (ADS)

    Filacchione, Gianrico

    2006-10-01

    Nel corso dell’ultimo decennio l’esplorazione planetaria ha potuto beneficiare dei dati prodotti dagli spettrometri ad immagine: grazie a questa nuova classe di strumenti, realizzati per l’osservazione in remoto di superfici ed atmosfere planetarie, è possibile acquisire dati iperspettrali con elevati poteri risolutivi spaziali e spettrali. Il principale vantaggio offerto dagli spettrometri ad immagine, rispetto alle camere ed agli spettrometri puntuali, è rappresentato dalla capacità di misurare, identificare e mappare le unità composizionali delle superfici planetarie; queste informazioni permettono di investigare sia l’evoluzione geochimica delle superfici sia la dinamica e la composizione delle atmosfere. Sebbene i primi spettrometri ad immagine siano stati francesi (Phobos/ISM, Imaging Spectrometer for Mars) e statunitensi (Galileo/NIMS, Near Infrared Mapping Spectrometer), il nostro paese nel corso degli ultimi anni è stato in grado di proporre alla com unità spaziale internazionale degli strumenti dalle elevate prestazioni che sono stati infatti accettati come payload scientifici su diverse missioni interplanetarie: dai canali visibili di VIMS (Visual and Infrared Mapping Spectrometer) su Cassini (Nasa, JPL, ESA, ASI) e di OMEGA (Observatoire pour la Minéralogie, l’Eau, les Glacies et l’Activitè de Mars) su MarsExpress (ESA) ai due VIRTIS (Visible and Infrared Thermal Imaging Spectrometer) su Rosetta (ESA) e VenusExpress (ESA) fino a VIR-MS (Visible and Infrared Mapping Spectrometer) su Dawn (Nasa). In questo momento inoltre altri due spettrometri sono in avanzata fase di studio: JIRAM (Jovian InfraRed Auroral Mapper) su Juno (missione New Discovery Nasa) e VIHI (Visible and Infrared Hyperspectral Imager) integrato nel payload italiano di remote sensing SIMBIO-SYS di BepiColombo (missione cornerstone ESA). La realizzazione di uno spettrometro ad immagini da utilizzare su una missione interplanetaria richiede un’accurata analisi in fase progettuale e realizzativa dei parametri e de lle prestazioni strumentali; in generale infatti non solo sarà necessario mantenere le dimensioni, il peso, i consumi elettrici ed il data-volume entro i requisiti disponibili del satellite ma anche ottimizzare i disegni ottici, meccanici ed elettronici al fine di ottenere le massime prestazioni possibili in funzione della natura del target osservato e dei parametri orbitali della missione. Questa tesi descrive i metodi utilizzati per caratterizzare il funzionamento di spettrometri ad immagine per l’esplorazione planetaria. L’attività svolta ha riguardato sia la misura in laboratorio dei parametri strumentali fondamentali sia l’analisi dei dati in volo su cui verificarne ed eventualmente correggerne la risposta. Il funzionamento degli strumenti e la metodologia di calibrazione vengono descritti nelle due parti principali e nelle appendici di questa tesi per gli esperimenti Cassini-VIMS-V e Rosetta-VIRTIS-M. La prima parte è dedicata all’esperimento VIMS-V sul satellite Cassini, il cui disegno ottico, originariamente proposto da Francis Reininger, verrà successivamente riutilizzato e perfezionato su VIRTIS-M (Reininger et al., 1994; Miller et al., 1996). Il capitolo 1 contiene una descrizione dei parametri ottici, strutturali, termici ed elettronici di VIMS-V mettendone in risalto gli aspetti più innovativi del progetto. Vengono inoltre descritti la collocazione dell’esperimento sul satellite Cassini, il coallineamento con gli altri strumenti di remote sensing, i possibili modi operativi ed il formato dei dati scientifici. Il capitolo 2 riguarda il processo di calibrazione ed analisi dei dati in volo di VIMS-V. La procedura eseguita per calibrare radiometricamente lo strumento utilizzando i dati della superficie della Luna e per stimare il flat-field mediante i dati dell’atmosfera di Venere viene dettagliatamente descritta assieme agli algoritmi utilizzati per la rimozione di diversi effetti strumentali (read-out noise e tilt spettrale); alcuni di questi effetti sono stati caratterizzati e dettagliamente misurati in laboratorio utilizzando il modello spare (flight) di VIMS-V. Parte del capitolo è dedicata alla verifica della procedura di calibrazione su diversi target aventi caratteristiche spettroradiometriche note. Questi algoritmi di processamento sono correntemente utilizzati dal team scientifico di VIMS per calibrare i dati del canale -VIS rilasciati ufficialmente alla comunità scientifica internazionale attraverso il Planetary Data System (PDS) della Nasa. La seconda parte riguarda l’esperimento VIRTIS-M sul satellite Rosetta. Il capitolo 3 contiene la descrizione dello strumento mettendo in risalto l’evoluzione dal precedente progetto VIMS-V ed i problemi tecnologici e costruttivi da questo derivanti. I diversi modi operativi, la sequenza di acquisizione e di processamento dei dati nell’elettronica principale sono ampiament e discussi. Viene inoltre evidenziata la collocazione dello spettrometro sul satellite Rosetta. Nel capitolo 4 viene descritta l’attività di calibrazione effettuata in Galileo Avionica (Campi Bisenzio, FI, Italia) ed allo IAS (Orsay, Francia) subito dopo l’integrazione di VIRTIS ed il conseguente processamento dei dati necessario per ricavare i principali parametri di funzionamento (calibrazioni spettrali e geometriche, flat-field, funzioni di trasferimento, lampade di calibrazione interne). Nel capitolo 5 l’accuratezza di queste grandezze è stata verificata su i primi dati in volo ottenuti da VIRTIS-M durante la fase di commissioning e di cruise del satellite (Terra, Luna e Saturno); queste osservazioni sono inoltre state utilizzate per migliorare e verificare alcuni aspetti della procedura di calibrazione che non erano stati sufficientemente definiti durante i test a terra. L’appendice A riguarda il formato PDS (Planetary Data System) utilizzato per l’archiviazione dei dati e degli housekeepings ingegnerisitici e scientifici delle osservazioni; nell’appendice B è contenuta la descrizione del modello radiometrico teorico di VIRTIS-M utilizzato per stimare il rapporto segnale/rumore; nelle appendici C e D sono infine contenute diverse Tabelle non incluse nel testo delle parti principali a causa della loro lunghezza.

  7. Di Sala syndrome.

    PubMed

    Kumar, Manoj; Bhasker, Shashi Kumar; Singh, Ragini; Kohli, Neera; Kumar, Rashmi

    2012-01-01

    Di Sala syndrome or fetal warfarin syndrome/fetal warfarin embryopathy is a rare condition as result of fetal exposure due to maternal ingestion of warfarin during pregnancy. The authors report here a male infant with this condition whose mother was suffering from rheumatic mitral valvular heart disease for which she underwent prosthetic mitral valvular replacement surgery and put on injectable long acting penicillin and oral low-molecular weight anticoagulant drug (warfarin) for life long. The patient presented with facial dysmorphism, pectus excavatum, stippled epiphyses dolichocephaly, brachydactyly, polydactyly short neck and growth retardation. Shortened fourth metacarpal bones were also noted in this case which was not yet reported in literatures, to the best of our knowledge. PMID:22605711

  8. Di(hydroxyphenyl)- benzimidazole monomers

    NASA Technical Reports Server (NTRS)

    Connell, John W. (Inventor); Hergenrother, Paul M. (Inventor); Smith, Joseph G. (Inventor)

    1993-01-01

    Di(hydroxyphenyl)benzimidazole monomers were prepared from phenyl-hydroxybenzoate and aromatic bis(o-diamine)s. These monomers were used in the synthesis of soluble polybenzimidazoles. The reaction involved the aromatic nucleophilic displacement of various di(hydroxyphenyl)benzimidazole monomers with activated aromatic dihalides or activated aromatic dinitro compounds in the presence of an alkali metal base. These polymers exhibited lower glass transition temperatures, improved solubility, and better compression moldability over their commercial counterparts.

  9. Trasforiiazioni Termoelastiche Finite di Solidi Incomprimibili

    NASA Astrophysics Data System (ADS)

    Signorini, A.

    Queste lezlioni hanno come direttiva una sintesi di quanto si trova sistematicamente sviluppato in una mia Memoria sulle trasformazioni termoelastiche finite di solidi incomprimibili, in corso di stampa negli Annali di Matematica pura e applicata t. XXXIX ( 1955) pp. 147-201 , Verranno anche esposti, come necessaria premessa, alcuni d ei risultati di due precedenti Memorie degli stessi Annali. Invece, per motivo di brevità, non potrò dare neppure un cenno delle ulteriori ricerche svilup pate dal prof. T. Manacorda in tre recentissimi suoi lavori:

  10. Di(2-ethylhexyl)adipate

    Integrated Risk Information System (IRIS)

    Di ( 2 - ethylhexyl ) adipate ; CASRN 103 - 23 - 1 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 Non

  11. The "Bestie di Satana" murders.

    PubMed

    Birkhoff, Jutta; Candelli, Chiara; Zeroli, Stefania; La Tegola, Donatella; Carabellese, Felice

    2013-11-01

    In recent years, satanic groups have been responsible for various types and degrees of crimes. We report the case of a number of murders committed in Italy by a group of young people calling themselves the "Bestie di Satana". Forensic psychiatric assessment of the members of a satanic sect charged with the crime revealed that all the young people had a fragile, immature personality, a very low level of education and were socially disadvantaged. The trial of the members of the "Bestie di Satana" sect was concluded with the verdict of deliberate murder, and all the members were given long jail sentences. This report should lead us to explore social and cultural responses to juvenile satanism, statistically shown to be a relatively rare phenomenon but with a high criminal potential. PMID:24117906

  12. Introduzione al Laboratorio di Fisica

    NASA Astrophysics Data System (ADS)

    Ciullo, Giuseppe

    La Fisica (dal greco τὰ ϕυσικὰ: le cose naturali) si pone l'obiettivo di descrivere e prevedere il comportamento dei fenomeni naturali, nonché degli apparati e degli strumenti, che hanno reso e rendono la nostra vita più comoda ed efficiente. Tale obiettivo viene perseguito mediante un'attenta osservazione dei fenomeni, con una conseguente schematizzazione dell'osservazione, per fornire una conoscenza della realtà oggettiva, affidabile, verificabile e condivisibile.

  13. Cyclic di-AMP mediates biofilm formation.

    PubMed

    Peng, Xian; Zhang, Yang; Bai, Guangchun; Zhou, Xuedong; Wu, Hui

    2016-03-01

    Cyclic di-AMP (c-di-AMP) is an emerging second messenger in bacteria. It has been shown to play important roles in bacterial fitness and virulence. However, transduction of c-di-AMP signaling in bacteria and the role of c-di-AMP in biofilm formation are not well understood. The level of c-di-AMP is modulated by activity of di-adenylyl cyclase that produces c-di-AMP and phosphodiesterase (PDE) that degrades c-di-AMP. In this study, we determined that increased c-di-AMP levels by deletion of the pdeA gene coding for a PDE promoted biofilm formation in Streptococcus mutans. Deletion of pdeA upregulated expression of gtfB, the gene coding for a major glucan producing enzyme. Inactivation of gtfB blocked the increased biofilm by the pdeA mutant. Two c-di-AMP binding proteins including CabPA (SMU_1562) and CabPB (SMU_1708) were identified. Interestingly, only CabPA deficiency inhibited both the increased biofilm formation and the upregulated expression of GtfB observed in the pdeA mutant. In addition, CabPA but not CabPB interacted with VicR, a known transcriptional factor that regulates expression of gtfB, suggesting that a signaling link between CabPA and GtfB through VicR. Increased biofilm by the pdeA deficiency also enhanced bacterial colonization of Drosophila in vivo. Taken together, our studies reveal a new role of c-di-AMP in mediating biofilm formation through a CabPA/VicR/GtfB signaling network in S. mutans. PMID:26564551

  14. Exclusive e+e-, di-photon and di-jet production at the Tevatron

    SciTech Connect

    Terashi, Koji; /Rockefeller U.

    2007-05-01

    Results from studies on exclusive production of electron-position pair, di-photon, and dijet production at CDF in proton-antiproton collisions at the Fermilab Tevatron are presented. THe first observation and cross section measurements of exclusive e{sup +}e{sup -} and di-jet production in hadron-hadron collisions are emphasized.

  15. Di-leptons at the Bevalac

    SciTech Connect

    Matis, H.S.

    1988-03-01

    Recent results on the production of di-leptons measured by the Di-Lepton-Spectrometer (DLS) collaboration are discussed. Results are reported from observations made on p /plus/ Be collisions with proton beams from 1.0 to 4.9 GeV and on Ca collisions with calcium beams of 1.0 to 2.0 GeV/A. The shape of the distributions are similar to that at higher energies. The low mass cross section appears to be explained by ..pi..-..pi.. annihilation, but detailed calculations are needed to substantiate that hypothesis. (LEN)

  16. Severe dystrophy in DiGeorge syndrome

    PubMed Central

    Rózsai, Barnabás; Kiss, Ákos; Csábi, Györgyi; Czakó, Márta; Decsi, Tamás

    2009-01-01

    We present the case history of a 3-year-old girl who was examined because of severe dystrophy. In the background, cow’s milk allergy was found, but her body weight was unchanged after eliminating milk from her diet. Other types of malabsorption were excluded. Based on nasal regurgitation and facial dysmorphisms, the possibility of DiGeorge syndrome was suspected and was confirmed by fluorescence in situ hybridization. The authors suggest a new feature associated with DiGeorge syndrome. PMID:19294771

  17. 40 CFR 721.305 - Di-substituted acetophenone (generic).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Di-substituted acetophenone (generic... Substances § 721.305 Di-substituted acetophenone (generic). (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified generically as di-substituted...

  18. URINARY BIOMARKERS OF DI-ISONONYL PHTHALATE IN RATS

    EPA Science Inventory

    Commercial di-isononyl phthalate (DiNP) is a mixture of various branched-chain dialkyl phthalates mainly containing ninecarbon alkyl isomers. At high doses in rodents, DiNP is a carcinogen, and a developmental toxicant. After exposure, the diester isomers are de-esterified to for...

  19. 21 CFR 178.3940 - Tetraethylene glycol di-(2-ethylhexoate).

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... SANITIZERS Certain Adjuvants and Production Aids § 178.3940 Tetraethylene glycol di-(2-ethylhexoate). Tetraethylene glycol di-(2-ethylhexoate) containing not more than 22 parts per million ethylene and/or... 21 Food and Drugs 3 2012-04-01 2012-04-01 false Tetraethylene glycol di-(2-ethylhexoate)....

  20. 21 CFR 178.3940 - Tetraethylene glycol di-(2-ethylhexoate).

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Tetraethylene glycol di-(2-ethylhexoate). 178.3940... Production Aids § 178.3940 Tetraethylene glycol di-(2-ethylhexoate). Tetraethylene glycol di-(2-ethylhexoate) containing not more than 22 parts per million ethylene and/or diethylene glycols may be used at a level...

  1. 21 CFR 178.3940 - Tetraethylene glycol di-(2-ethylhexoate).

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... SANITIZERS Certain Adjuvants and Production Aids § 178.3940 Tetraethylene glycol di-(2-ethylhexoate). Tetraethylene glycol di-(2-ethylhexoate) containing not more than 22 parts per million ethylene and/or... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Tetraethylene glycol di-(2-ethylhexoate)....

  2. Detection of cyclic di-AMP using a competitive ELISA with a unique pneumococcal cyclic di-AMP binding protein

    PubMed Central

    Underwood, Adam J.; Zhang, Yang; Metzger, Dennis W.; Bai, Guangchun

    2014-01-01

    Cyclic di-AMP (c-di-AMP) is a signaling molecule that has been shown to play important roles in bacterial physiology and infections. Currently, c-di-AMP detection and quantification relies mostly on the use of high-performance liquid chromatography (HPLC) or liquid chromatography-mass spectrometry (LC-MS). In this study, a competitive enzyme-linked immunosorbent assay (ELISA) for the quantification of c-di-AMP was developed, which utilizes a novel pneumococcal c-di-AMP binding protein (CabP) and a newly commercialized c-di-AMP derivative. With this new method, c-di-AMP concentrations in biological samples can be quickly and accurately quantified. Furthermore, this assay is much more efficient than current methods as it requires less overall cost and training while processing many samples at once. Therefore, this assay can be extensively used in research into c-di-AMP signaling. PMID:25239824

  3. Protoisomerization of indigo di- and monoimines.

    PubMed

    Nicholls-Allison, Emma C; Nawn, Graeme; Patrick, Brian O; Hicks, Robin G

    2015-08-11

    Indigo di- and monoimines can be protonated to form stable salts in which the central C=C bond has isomerized from a trans to cis configuration. Deprotonation of these salts regenerates the neutral trans species. The protonation chemistry of indigo is also explored. PMID:26146012

  4. Di-hadron production at Jefferson Lab

    SciTech Connect

    Anefalos Pereira, Sergio; et. al.,

    2014-10-01

    Semi-inclusive deep inelastic scattering (SIDIS) has been used extensively in recent years as an important testing ground for QCD. Studies so far have concentrated on better determination of parton distribution functions, distinguishing between the quark and antiquark contributions, and understanding the fragmentation of quarks into hadrons. Hadron pair (di-hadron) SIDIS provides information on the nucleon structure and hadronization dynamics that complement single hadron SIDIS. Di-hadrons allow the study of low- and high-twist distribution functions and Dihadron Fragmentation Functions (DiFF). Together with the twist-2 PDFs ( f1, g1, h1), the Higher Twist (HT) e and hL functions are very interesting because they offer insights into the physics of the largely unexplored quark-gluon correlations, which provide access into the dynamics inside hadrons. The CLAS spectrometer, installed in Hall-B at Jefferson Lab, has collected data using the CEBAF 6 GeV longitudinally polarized electron beam on longitudinally polarized solid NH3 targets. Preliminary results on di-hadron beam-, target- and double-spin asymmetries will be presented.

  5. N-Nitroso-di-n-butylamine

    Integrated Risk Information System (IRIS)

    N - Nitroso - di - n - butylamine ; CASRN 924 - 16 - 3 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

  6. Di (2-ethylhexyl)phthalate (DEHP)

    Integrated Risk Information System (IRIS)

    Di ( 2 - ethylhexyl ) phthalate ( DEHP ) ; CASRN 117 - 81 - 7 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 Assessme

  7. [Valutazione delle guardie di sicurezza privata attraverso la Suicide Probability Scale e la Brief Symptom Inventory].

    PubMed

    Dogan, Bulent; Canturk, Gurol; Canturk, Nergis; Guney, Sevgi; Özcan, Ebru

    2016-01-01

    RIASSUNTO. Scopo. Lo scopo di questo studio è stato quello di investigare l'influenza della probabilità di suicidio, con le sue caratteristiche sociodemografiche, e di procurare i dati per la prevenzione del suicidio tra le guardie di sicurezza privata che lavorano in condizioni di stress, essendo a contatto ininterrottamente con eventi negativi e traumatici di vita durante il loro lavoro. Metodi. Hanno partecipato allo studio 200 guardie di sicurezza privata e 200 persone dell'Università di Ankara. Per raccogliere i dati sono stati utilizzati un questionario riguardante le condizioni sociodemografiche dei partecipanti, la Suicide Probability Scale (SPS) e la Brief Symptom Inventory (BSI). Risultati. Genere, stato civile, stipendio, credenze religiose, vivere una situazione di pericolo di vita, passato di tentativi di suicidio, fumare e non avere una malattia cronica hanno causato statisticamente una differenza significativa sui punteggi di SPS tra il gruppo di guardie di sicurezza privata e quello di controllo. In aggiunta, c'è stata una correlazione positiva statisticamente significativa tra i punteggi totali delle sottoscale di SPS e quelli di BSI. Conclusioni. Allo stesso modo degli agenti di polizia e dei gendarmi, le guardie di sicurezza privata sono ad alto rischio di commettere e tentare il suicidio trovandosi in condizioni stressanti di lavoro e anche soffrendo del trauma secondario. È necessario che essi siano consapevoli della propria tendenza al suicidio e avere controlli psichiatrici regolari. PMID:27183512

  8. CYCLIC DI-NUCLEOTIDE SIGNALLING ENTERS THE EUKARYOTE DOMAIN

    PubMed Central

    Schaap, Pauline

    2014-01-01

    SUMMARY Cyclic di-GMP (c-di-GMP) is the prevalent intracellular signalling intermediate in bacteria. It triggers a spectrum of responses that cause bacteria to shift from a swarming motile phase to sessile biofilm formation. However, additional functions for c-di-GMP and roles for related molecules, such as c-di-AMP and c-AMP-GMP continue to be uncovered. The first usage of cyclic-di-nucleotide (c-di-NMP) signalling in the eukaryote domain emerged only recently. In Dictyostelid social amoebas, c-di-GMP is a secreted signal that induces motile amoebas to differentiate into sessile stalk cells. In humans, c-di-NMPs, which are either produced endogenously in response to foreign DNA or by invading bacterial pathogens, trigger the innate immune system by activating the expression of interferon genes. STING, the human c-di-NMP receptor, is conserved throughout metazoa and their closest unicellular relatives, suggesting protist origins for human c-di-NMP signalling. Compared to the limited number of conserved protein domains that detect the second messengers cAMP and cGMP, the domains that detect the c-di-NMPs are surprisingly varied. PMID:24136904

  9. Biomaterial based sulphur di oxide gas sensor

    NASA Astrophysics Data System (ADS)

    Ghosh, P. K.; Sarkar, A.

    2013-06-01

    Biomaterials are getting importance in the present research field of sensors. In this present paper performance of biomaterial based gas sensor made of gum Arabica and garlic extract had been studied. Extract of garlic clove with multiple medicinal and chemical utility can be proved to be useful in sensing Sulphur di Oxide gas. On exposure to Sulphur di Oxide gas the material under observation suffers some temporary structural change, which can be observed in form of amplified potentiometric change through simple electronic circuitry. Exploiting this very property a potentiometric gas sensor of faster response and recovery time can be designed. In this work sensing property of the said material has been studied through DC conductance, FTIR spectrum etc.

  10. Di-interstitial defect in silicon revisited

    SciTech Connect

    Londos, C. A.; Antonaras, G.; Chroneos, A.; Department of Materials, Imperial College London, London SW7 2BP

    2013-11-21

    Infrared spectroscopy was used to study the defect spectrum of Cz-Si samples following fast neutron irradiation. We mainly focus on the band at 533 cm{sup −1}, which disappears from the spectra at ∼170 °C, exhibiting similar thermal stability with the Si-P6 electron paramagnetic resonance (EPR) spectrum previously correlated with the di-interstitial defect. The suggested structural model of this defect comprises of two self-interstitial atoms located symmetrically around a lattice site Si atom. The band anneals out following a first-order kinetics with an activation energy of 0.88 ± 0.3 eV. This value does not deviate considerably from previously quoted experimental and theoretical values for the di-interstitial defect. The present results indicate that the 533 cm{sup −1} IR band originates from the same structure as that of the Si-P6 EPR spectrum.

  11. Di-boson physics at the Tevatron

    SciTech Connect

    Goshaw, A.T.; /Duke U.

    2005-07-01

    A summary is presented of recent measurements of di-boson production at the Tevatron. The results from the CDF and D0 experiments are based upon 130-320 pb{sup -1} of p{bar p} collisions at {radical}s = 1.96 TeV. The W{gamma}, Z{gamma}, WW, and WZ production properties are compared to Standard Model predictions, and limits extracted for anomalous triple gauge couplings.

  12. [Donatori di Musica: when oncology meets music].

    PubMed

    Graiff, Claudio

    2014-10-01

    Donatori di Musica is a network of musicians - both physicians and volunteers - that was initially founded in 2009 with the aim to set up and coordinate classical music concerts in hospitals. This activity was initially started and led by the Oncology Departments at Carrara and Bolzano Hospitals, where high profile professional musicians make themselves available for concerts in support of Oncological in/out-patients of that specific Hospital. A live classical music performance is a deeply touching experience - particularly for those who live a critical condition like cancer. Main characteristics of Donatori di Musica concerts are: continuity (concerts are part of a regular and non-stopping music season); quality (concerts are held by well-established professional musicians); philanthropic attitude (musicians do not wear a suit and usually chat with patients; they also select an easy-to-listen program; a convivial event is usually organized after the performance with the aim of overcoming distinctions and barriers between physician and patient); no profit: musicians perform for free - travel expenses and/or overnight staying only can be claimed; concerts have free access for patients, their families and hospital staff.Patients and musicians therefore do get in close contact and music is able to merge each other experiences - with patients being treated by the beauty of music and musicians being treated theirselves by patients daily-life feedback. The Donatori di Musica experience is therefore able to help Medicine to retrieve its very first significance - the medical act regain that human and cultural dimension that seems to be abandoned in the last decades in favour of a mere technicism. This is the spirit and the deep significance of Donatori di Musica - «[…] the hope that Music can become a key support to medical treatments in every Oncology department» (by Gian Andrea Lodovici). PMID:25282347

  13. Cyclic di-nucleotide signaling enters the eukaryote domain.

    PubMed

    Schaap, Pauline

    2013-11-01

    Cyclic (c-di-GMP) is the prevalent intracellular signaling intermediate in bacteria. It triggers a spectrum of responses that cause bacteria to shift from a swarming motile phase to sessile biofilm formation. However, additional functions for c-di-GMP and roles for related molecules, such as c-di-AMP and c-AMP-GMP continue to be uncovered. The first usage of cyclic-di-nucleotide (c-di-NMP) signaling in the eukaryote domain emerged only recently. In dictyostelid social amoebas, c-di-GMP is a secreted signal that induces motile amoebas to differentiate into sessile stalk cells. In humans, c-di-NMPs, which are either produced endogenously in response to foreign DNA or by invading bacterial pathogens, trigger the innate immune system by activating the expression of interferon genes. STING, the human c-di-NMP receptor, is conserved throughout metazoa and their closest unicellular relatives, suggesting protist origins for human c-di-NMP signaling. Compared to the limited number of conserved protein domains that detect the second messengers cAMP and cGMP, the domains that detect the c-di-NMPs are surprisingly varied. PMID:24136904

  14. Cyclic Di-AMP Impairs Potassium Uptake Mediated by a Cyclic Di-AMP Binding Protein in Streptococcus pneumoniae

    PubMed Central

    Bai, Yinlan; Yang, Jun; Zarrella, Tiffany M.; Zhang, Yang; Metzger, Dennis W.

    2014-01-01

    Cyclic di-AMP (c-di-AMP) has been shown to play important roles as a second messenger in bacterial physiology and infections. However, understanding of how the signal is transduced is still limited. Previously, we have characterized a diadenylate cyclase and two c-di-AMP phosphodiesterases in Streptococcus pneumoniae, a Gram-positive pathogen. In this study, we identified a c-di-AMP binding protein (CabP) in S. pneumoniae using c-di-AMP affinity chromatography. We demonstrated that CabP specifically bound c-di-AMP and that this interaction could not be interrupted by competition with other nucleotides, including ATP, cAMP, AMP, phosphoadenylyl adenosine (pApA), and cyclic di-GMP (c-di-GMP). By using a bacterial two-hybrid system and genetic mutagenesis, we showed that CabP directly interacted with a potassium transporter (SPD_0076) and that both proteins were required for pneumococcal growth in media with low concentrations of potassium. Interestingly, the interaction between CabP and SPD_0076 and the efficiency of potassium uptake were impaired by elevated c-di-AMP in pneumococci. These results establish a direct c-di-AMP-mediated signaling pathway that regulates pneumococcal potassium uptake. PMID:24272783

  15. Thermal and optical studies of some di-methyl-di-alkyl ammonium bromides

    NASA Astrophysics Data System (ADS)

    Witko, Waclaw; Godlewska, Malgorzata; Dynarowicz, Patrycja

    1998-01-01

    Phase situation of homologous series of di-alkyl-di-methyl ammonium bromides represented by the general formula: 2CnN+2C1Br-, with n equals 10, 12, 14, 16, 18, was investigated by means of differential scanning calorimetry and optical microscopy methods in the temperature range 20-180 degrees C. A more complex polymorphism as already reported was detected. All the compounds studied show at least tow anomalies on the DSC curves. The high-temperature phase which appears below the isotropic phase has lancet-like dendritic texture which can be attributed to SmB phase. The enthalpy changes at the transitions were calculated.

  16. Absent Aortic Valve in DiGeorge Syndrome.

    PubMed

    Bertsch, Elizabeth C; Minturn, Lucy; Gotteiner, Nina L; Ernst, Linda M

    2016-01-01

    A 20-week-old fetus with the 22q11.2 deletion characteristic of DiGeorge syndrome is described with vertebral segmentation abnormalities and complex cardiovascular anomalies including an absent aortic valve. This is only the second known case of absent aortic valve in association with DiGeorge syndrome. We discuss the association of absent aortic valve with other conotruncal defects and the utility of fetal echocardiography in the diagnosis of DiGeorge syndrome. PMID:26230226

  17. Meningococco B: controllo di due focolai epidemici mediante vaccinazione

    PubMed Central

    2014-01-01

    Riassunto La problematica di un efficace approccio vaccinale nei confronti del Meningococco B (MenB) è stata superata identificando con la metodica della "reverse vaccinology" alcuni antigeni capaci di indurre una risposta verso la maggior parte dei ceppi di MenB circolanti nel mondo. Il nuovo vaccino MenB a 4 componenti (4CMenB) è stato autorizzato in Europa, Australia e Canada, ed è entrato nei calendari di immunizzazione pediatrica internazionali: Australia, Canada, UK. In Italia, le prime regioni che hanno raccomandato la vaccinazione contro il MenB sono state Basilicata e Puglia. La gestione di epidemie/focolai epidemici richiede la messa in atto di una risposta rapida da parte delle autorità sanitarie nei confronti di una emergenza sanitaria ad elevato impatto, anche emotivo, sulla popolazione, come recentemente dimostrato in due università americane. Alla dichiarazione di focolaio epidemico in atto, in entrambi i contesti si è attivata una procedura per l'uso del vaccino 4CMenB non ancora autorizzato negli USA. È stato così possibile organizzare gli interventi di profilassi attiva nei due campus universitari, adottando il primo impiego su larga scala del nuovo vaccino 4CMenB e conseguendo, in tempi relativamente brevi, elevati tassi di copertura vaccinale. A fronte di circa 14000 studenti immunizzati con almeno una dose, non è stata segnalata alcuna problematica di eventi avversi conseguenti all'immunizzazione; ad oggi non si sono verificati casi nei soggetti che hanno ricevuto il vaccino. Come conseguenza dei due focolai descritti, è oggi in corso la valutazione da parte dell'FDA per l'estensione dell'uso del vaccino 4CMenB negli Stati Uniti negli adolescenti e giovani adulti. PMID:25916017

  18. Cyclic-di-GMP and cyclic-di-AMP activate the NLRP3 inflammasome

    PubMed Central

    Abdul-Sater, Ali A; Tattoli, Ivan; Jin, Lei; Grajkowski, Andrzej; Levi, Assaf; Koller, Beverly H; Allen, Irving C; Beaucage, Serge L; Fitzgerald, Katherine A; Ting, Jenny P -Y; Cambier, John C; Girardin, Stephen E; Schindler, Christian

    2013-01-01

    The cyclic dinucleotides 3'-5'diadenylate (c-diAMP) and 3'-5' diguanylate (c-diGMP) are important bacterial second messengers that have recently been shown to stimulate the secretion of type I Interferons (IFN-Is) through the c-diGMP-binding protein MPYS/STING. Here, we show that physiologically relevant levels of cyclic dinucleotides also stimulate a robust secretion of IL-1β through the NLRP3 inflammasome. Intriguingly, this response is independent of MPYS/STING. Consistent with most NLRP3 inflammasome activators, the response to c-diGMP is dependent on the mobilization of potassium and calcium ions. However, in contrast to other NLRP3 inflammasome activators, this response is not associated with significant changes in mitochondrial potential or the generation of mitochondrial reactive oxygen species. Thus, cyclic dinucleotides activate the NLRP3 inflammasome through a unique pathway that could have evolved to detect pervasive bacterial pathogen-associated molecular patterns associated with intracellular infections. PMID:24008845

  19. Efficient heterocyclisation by (di)terpene synthases.

    PubMed

    Mafu, S; Potter, K C; Hillwig, M L; Schulte, S; Criswell, J; Peters, R J

    2015-09-11

    While cyclic ether forming terpene synthases are known, the basis for such heterocyclisation is unclear. Here it is reported that numerous (di)terpene synthases, particularly including the ancestral ent-kaurene synthase, efficiently produce isomers of manoyl oxide from the stereochemically appropriate substrate. Accordingly, such heterocyclisation is easily accomplished by terpene synthases. Indeed, the use of single residue changes to induce production of the appropriate substrate in the upstream active site leads to efficient bifunctional enzymes producing isomers of manoyl oxide, representing novel enzymatic activity. PMID:26214384

  20. DiTour 3.1

    SciTech Connect

    Pelaia II, Thomas A.

    2015-06-30

    There is a need for software that allows a tour guide to present different tracks of slides and then return to the default slide show automatically upon completion. A mobile solution is needed for trade shows. DiTour is an iPad/iPhone app that pulls presentation content from a website, stores it on the device and presents it on a connected display. A tour guide can select a track to present and it will automatically return to the default track after a timeout. It offers a mobile solution which is ideal for trade shows.

  1. DiTour 3.1

    Energy Science and Technology Software Center (ESTSC)

    2015-06-30

    There is a need for software that allows a tour guide to present different tracks of slides and then return to the default slide show automatically upon completion. A mobile solution is needed for trade shows. DiTour is an iPad/iPhone app that pulls presentation content from a website, stores it on the device and presents it on a connected display. A tour guide can select a track to present and it will automatically return tomore » the default track after a timeout. It offers a mobile solution which is ideal for trade shows.« less

  2. The cyclic di-nucleotide c-di-AMP is an allosteric regulator of metabolic enzyme function

    PubMed Central

    Precit, Mimi; Delince, Matthieu; Pensinger, Daniel; Huynh, TuAnh Ngoc; Jurado, Ashley R.; Goo, Young Ah; Sadilek, Martin; Iavarone, Anthony T.; Sauer, John-Demian; Tong, Liang; Woodward, Joshua J.

    2014-01-01

    SUMMARY Cyclic di-adenosine monophosphate (c-di-AMP) is a broadly conserved second messenger required for bacterial growth and infection. However, the molecular mechanisms of c-di-AMP signaling are still poorly understood. Using a chemical proteomics screen for c-di-AMP interacting proteins in the pathogen Listeria monocytogenes, we identified several broadly conserved protein receptors, including the central metabolic enzyme pyruvate carboxylase (LmPC). Biochemical and crystallographic studies of the LmPC-c-di-AMP interaction revealed a previously unrecognized allosteric regulatory site 25 Å from the active site. Mutations in this site disrupted c-di-AMP binding and affected enzyme catalysis of LmPC as well as PC from pathogenic Enterococcus faecalis. C-di-AMP depletion resulted in altered metabolic activity in L. monocytogenes. Correction of this metabolic imbalance rescued bacterial growth, reduced bacterial lysis, and resulted in enhanced bacterial burdens during infection. These findings greatly expand the c-di-AMP signaling repertoire and reveal a central metabolic regulatory role for a cyclic di-nucleotide. PMID:25215494

  3. Live viral vaccines in a DiGeorge syndrome patient.

    PubMed

    Waters, V; Peterson, K S; LaRussa, P

    2007-06-01

    We report a case of pneumonia in a 13 month old male child with partial DiGeorge syndrome who died after inadvertently receiving live viral vaccines. Although live viral vaccines have been used safely in some children with DiGeorge syndrome, there are insufficient data to recommend their routine use in those with severe immunodeficiency. PMID:16798784

  4. Interdisciplinary investigations in support of project DI-MOD

    NASA Technical Reports Server (NTRS)

    Starks, Scott A.

    1991-01-01

    Interdisciplinary investigations in support of project DI-MOD are discussed. The following subject areas were covered: (1) potential extensions of Project DI-MOD to additional sites in Central America; (2) human migration patterns and their impact on malaria transmission; and (3) an investigation into possible computer-based approaches to the analysis of remotely sensed multispectral data.

  5. Sul foro nella stanza di Nicola Cusano al castello di Andraz: un'ipotesi astronomica

    NASA Astrophysics Data System (ADS)

    de Donà, G.

    2011-02-01

    Nicolas Krebs (Kues 1401 - Todi 1464), also called Nicola Cusano, or Nicholas of Cusa - reached the Castello di Andraz (BL, Italy), where he lived for a long period. In a wall of his room there is a hole representing a possible astronomical function. In this paper, the author illustrates the orientation of the hole and suggests that it is been created by the great German thinker to correct the Julian calendar.

  6. Di-photon excess illuminates dark matter

    NASA Astrophysics Data System (ADS)

    Backović, Mihailo; Mariotti, Alberto; Redigolo, Diego

    2016-03-01

    We propose a simplified model of dark matter with a scalar mediator to accommodate the di-photon excess recently observed by the ATLAS and CMS collaborations. Decays of the resonance into dark matter can easily account for a relatively large width of the scalar resonance, while the magnitude of the total width combined with the constraint on dark matter relic density leads to sharp predictions on the parameters of the Dark Sector. Under the assumption of a rather large width, the model predicts a signal consistent with ˜ 300 GeV dark matter particle and ˜ 750 GeV scalar mediator in channels with large missing energy. This prediction is not yet severely bounded by LHC Run I searches and will be accessible at the LHC Run II in the jet plus missing energy channel with more luminosity. Our analysis also considers astro-physical constraints, pointing out that future direct detection experiments will be sensitive to this scenario.

  7. Phosphorylation of serine residue modulates cotton Di19-1 and Di19-2 activities for responding to high salinity stress and abscisic acid signaling

    PubMed Central

    Qin, Li-Xia; Nie, Xiao-Ying; Hu, Rong; Li, Gang; Xu, Wen-Liang; Li, Xue-Bao

    2016-01-01

    Di19 (drought-induced protein 19) family is a novel type of Cys2/His2 zinc-finger proteins. In this study, we demonstrated that cotton Di19-1 and Di19-2 (GhDi19-1/-2) proteins could be phosphorylated in vitro by the calcium-dependent protein kinase (CDPK). Mutation of Ser to Ala in N-terminus of GhDi19-1/-2 led to the altered subcellular localization of the two proteins, but the constitutively activated form (Ser was mutated to Asp) of GhDi19-1/-2 still showed the nuclear localization. GhDi19-1/-2 overexpression transgenic Arabidopsis seedlings displayed the hypersensitivity to high salinity and abscisic acid (ABA). However, Ser site-mutated GhDi19-1(S116A) and GhDi19-2(S114A), and Ser and Thr double sites-mutated GhDi19-1(S/T-A/A) and GhDi19-2(S/T-A/A) transgenic Arabidopsis did not show the salt- and ABA-hypersensitive phenotypes. In contrast, overexpression of Thr site-mutated GhDi19-1(T114A) and GhDi19-2(T112A) in Arabidopsis still resulted in salt- and ABA-hypersensitivity phenotypes, like GhDi19-1/-2 transgenic lines. Overexpression of GhDi19-1/-2 and their constitutively activated forms in Atcpk11 background could recover the salt- and ABA-insensitive phenotype of the mutant. Thus, our results demonstrated that Ser phosphorylation (not Thr phosphorylation) is crucial for functionally activating GhDi19-1/-2 in response to salt stress and ABA signaling during early plant development, and GhDi19-1/-2 proteins may be downstream targets of CDPKs in ABA signal pathway. PMID:26829353

  8. ParaDiS-FEM dislocation dynamics simulation code primer

    SciTech Connect

    Tang, M; Hommes, G; Aubry, S; Arsenlis, A

    2011-09-27

    The ParaDiS code is developed to study bulk systems with periodic boundary conditions. When we try to perform discrete dislocation dynamics simulations for finite systems such as thin films or cylinders, the ParaDiS code must be extended. First, dislocations need to be contained inside the finite simulation box; Second, dislocations inside the finite box experience image stresses due to the free surfaces. We have developed in-house FEM subroutines to couple with the ParaDiS code to deal with free surface related issues in the dislocation dynamics simulations. This primer explains how the coupled code was developed, the main changes from the ParaDiS code, and the functions of the new FEM subroutines.

  9. Vibrational frequencies and structural determinations of di-vinyl sulfone

    NASA Astrophysics Data System (ADS)

    Ellzy, Michael W.; Jensen, James O.; Kay, Jack G.

    2003-03-01

    We present a detailed analysis of the structure and infrared spectra of di-vinyl sulfone. The vibrational frequencies of the di-vinyl sulfone molecule were analyzed using standard quantum chemical techniques. Frequencies were calculated at the MP2 and DFT levels of theory using the standard 6-311G* basis set. The structural transformation of the chemical agent bis(2-chloroehtyl) sulfide (HD, mustard gas) and the related symmetry to a previously study compounds [Spectrochim. Acta Part A 55 (1999) 121; Spectrochim. Acta Part A 57 (2001) 2417] makes the symmetry of the di-vinyl sulfone molecule an interesting candidate for study. The molecule exists normally in a C2 configuration. High-energy forms of di-vinyl sulfone with CS and C1 symmetries also exist.

  10. Synthesis, physicochemical, and tribological characterization of S-Di-n-octoxyboron-O,O'-di-n-octyldithiophosphate.

    PubMed

    Shah, Faiz Ullah; Glavatskih, Sergei; Antzutkin, Oleg N

    2009-12-01

    Dialkyldithiophosphates (DTPs) of zinc(II), copper(II), and other metals have been extensively used as multifunctional additives in lubricants to control friction and reduce wear in mechanical systems. Among these DTP compounds, zinc dialkyldithiophosphates (ZnDTPs) are the most common additives extensively used for more than 60 years. These additives form a protective film on steel surfaces and, thus, control friction and reduce wear. However, ZnDTPs contain zinc and large amounts of phosphorus and sulfur, which impair the environment, both directly and indirectly, by adversely affecting the performance of catalytic converters of various automobiles. For this reason, environmental legislation imposes limitations on concentrations of phosphorus, sulfur, and zinc in the lubricants. In this work, we report on zinc-free S-di-n-octoxyboron-O,O'-di-n-octyldithiophosphate (DOB-DTP) lubricant additive with amount of phosphorus and sulfur reduced by half in a molecule as compared with ZnDTPs. DOB-DTP was synthesized by a reaction in two steps under inert nitrogen atmosphere. The final product, a viscous liquid, was characterized by the elemental analysis, FT-IR, multinuclear (1)H, (13)C, (31)P, and (11)B NMR spectroscopy and thermal analyses. Tribological performance of a mineral oil with this new additive was evaluated in comparison with O,O'-di-n-butyl-dithiophosphato-zinc(II) (ZnDTP) using a four-ball tribometer. The surface morphology and the elemental composition of the tribofilms were characterized using scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM/EDS). The results show that DOB-DTP has a considerably better antiwear performance and higher stability of the coefficient of friction with time as compared with ZnDTP. Both phosphorus and sulfur were detected by the EDS on the worn steel surfaces at all concentrations of additives in the base oil. PMID:20356164

  11. Biosynthesis of di-(2-ethylhexyl) phthalate (DEHP) and di-n-butyl phthalate (DBP) from red alga--Bangia atropurpurea.

    PubMed

    Chen, Chih Yu

    2004-02-01

    The contents of di-(2-ethylhexyl) phthalate (DEHP) and di-n-butyl phthalate (DBP) of red alga, Bangia atropurpurea, filaments cultured in artificial sea water medium were similar to those cultured in natural sea water medium. In the culture experiment, B. atropurpurea filaments were found to synthesize de novo phthalate esters. Additionally, DEHP and DBP contents in different species of algae grown in the same environment were different significantly, suggesting that it was due to the intrinsic nature of algae. PMID:14769421

  12. DDX41 recognizes bacterial secondary messengers cyclic di-GMP and cyclic di-AMP to activate a type I interferon immune response

    PubMed Central

    Parvatiyar, Kislay; Zhang, Zhiqiang; Teles, Rosane M; Ouyang, Songying; Jiang, Yan; Iyer, Shankar S; Zaver, Shivam A; Schenk, Mirjam; Zeng, Shang; Zhong, Wenwan; Liu, Zhi-Jie; Modlin, Robert L; Liu, Yongjun; Cheng, Genhong

    2012-01-01

    Induction of type I interferons by the bacterial secondary messengers cyclic-di-GMP (c-di-GMP) or cyclic-di-AMP (c-di-AMP) is dependent on a signaling axis involving the STING adaptor, TBK1 kinase and IRF3 transcription factor. Here we identified the helicase DEAD box polypeptide 41 (DDX41) as a pattern recognition receptor (PRR) that sensed both c-di-GMP and c-di-AMP. DDX41 specifically and directly interacted with c-di-GMP. Knockdown of DDX41 via shRNA in murine or human cells inhibited the induction of innate immune genes and resulted in defective STING, TBK1 and IRF3 activation in response to c-di-GMP or c-di-AMP. These results suggest a mechanism whereby c-di-GMP and c-di-AMP are detected by the DDX41 PRR, which complexes with STING to signal to TBK1-IRF3 and activate the interferon response. PMID:23142775

  13. The helicase DDX41 recognizes the bacterial secondary messengers cyclic di-GMP and cyclic di-AMP to activate a type I interferon immune response.

    PubMed

    Parvatiyar, Kislay; Zhang, Zhiqiang; Teles, Rosane M; Ouyang, Songying; Jiang, Yan; Iyer, Shankar S; Zaver, Shivam A; Schenk, Mirjam; Zeng, Shang; Zhong, Wenwan; Liu, Zhi-Jie; Modlin, Robert L; Liu, Yong-jun; Cheng, Genhong

    2012-12-01

    The induction of type I interferons by the bacterial secondary messengers cyclic di-GMP (c-di-GMP) or cyclic di-AMP (c-di-AMP) is dependent on a signaling axis that involves the adaptor STING, the kinase TBK1 and the transcription factor IRF3. Here we identified the heliase DDX41 as a pattern-recognition receptor (PRR) that sensed both c-di-GMP and c-di-AMP. DDX41 specifically and directly interacted with c-di-GMP. Knockdown of DDX41 via short hairpin RNA in mouse or human cells inhibited the induction of genes encoding molecules involved in the innate immune response and resulted in defective activation of STING, TBK1 and IRF3 in response to c-di-GMP or c-di-AMP. Our results suggest a mechanism whereby c-di-GMP and c-di-AMP are detected by DDX41, which forms a complex with STING to signal to TBK1-IRF3 and activate the interferon response. PMID:23142775

  14. Biological effects summary report di(2-ethylhexyl) sebacate

    SciTech Connect

    Silverstein, B.D.; White, O. Jr.; Brower, J.E.; Bernholc, N.M.

    1983-10-01

    An evaluation of the health effects of di(2-ethylhexyl) sebacate (DEHS) was made to assess its potential use as substitute for di(2-ethylhexyl) phthalate (DEHP), which is used as a test aerosol in quantitative fit testing of respirators. A review of published and unpublished information on toxicity of DEHS was made. The limited amount of data on DEHS indicated that it has a low level of toxicity to laboratory animals. No oral or inhalation toxicity studies on humans were found, but skin sensitization and irritation studies were negative. Insufficeint data exists at present to permit determination of DEHS carcinogenicity. Because of structural similarities of DEHS to DEHP and di(ethylhexyl) adipate, and because these latter two materials have been shown to be carcinogenic in rats and mice, DEHS is not recommended at this time as a DEHP substitute until lack of its carcinogenic potential is confirmed.

  15. Carbon dioxide emissions from Specchio di Venere, Pantelleria, Italy

    NASA Astrophysics Data System (ADS)

    Paz, Mariana P. Jácome; Inguaggiato, Salvatore; Taran, Yuri; Vita, Fabio; Pecoraino, Giovanella

    2016-04-01

    We have mapped the diffuse CO2 efflux from the Specchio di Venere Lake area using the accumulation chamber method. We calculated a CO2 emission of 43 ± 5 t day-1 for the area studied, accounting for both diffuse degassing from soil and bubbling through the lake. We also present data on the water composition of Specchio di Venere Lake, the Polla 3 spring, and Liuzza well. On the basis of water chemistry, two physical-chemical processes, evaporation and mineral precipitation of carbonate species, are invoked to explain the CO2 degassing for the lake area.

  16. Target Search & Selection for the DI/EPOXI Spacecraft

    NASA Technical Reports Server (NTRS)

    Grebow, Daniel J.; Bhaskaran, Shyam; Chesley, Steven R.

    2012-01-01

    Upon completion of the Hartley 2 flyby in November 2010, the Deep Impact (DI) spacecraft resided in a solar orbit without possibility for gravity assist with any large body. Conservative estimates of remaining fuel were enough to provide only an 18 m/s impulse on the spacecraft. We present our method and results of our systematic scan of potential small body encounters for DI, and our criteria to narrow the selection to the asteroid 2002 GT as the target flyby body. The mission profile has two deterministic maneuvers to achieve the encounter, the first of which executed on November 25, 2011.

  17. Target Search and Selection for the DI/EPOXI Spacecraft

    NASA Technical Reports Server (NTRS)

    Grebow, Daniel J.; Bhaskaran, Shyam; Chesley, Steven R.

    2012-01-01

    Upon completion of the Hartley 2 flyby in November 2010, the Deep Impact (DI) spacecraft resided in a solar orbit without possibility for gravity assist with any large body. Conservative estimates of remaining fuel were enough to provide only an 18 m/s impulse on the spacecraft. We present our method and results of our systematic scan of potential small body encounters for DI, and our criteria to narrow the selection to the asteroid 2002 GT as the target flyby body. The mission profile has two deterministic maneuvers to achieve the encounter, the first of which executed on November 25, 2011.

  18. 4-(Di-methyl-amino)-pyridinium trichlorido[4-(di-methyl-amino)-pyridine-κN]cobaltate(II).

    PubMed

    Guenifa, Fatiha; Hadjadj, Nasreddine; Zeghouan, Ouahida; Bendjeddou, Lamia; Merazig, Hocine

    2013-01-01

    In the anion of the title compound, (C7H11N2)[CoCl3(C7H10N2)], the Co(II) ion is coordinated by one N atom from a 4-(di-methyl-amino)-pyridine (DMAP) ligand and three Cl atoms, forming a CoNCl3 polyhedron with a distorted tetra-hedral geometry. In the crystal, cations and anions are linked via weak N-H⋯Cl and C-H⋯Cl hydrogen bonds. Double layers of complex anions stack along the b- axis direction, which alternate with double layers of 4-(di-methyl-amino)-pyridinium cations. PMID:24046560

  19. 40 CFR 721.2094 - N,N′-di(alkyl heteromonocycle)amino chlorotriazine.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false N,Nâ²-di(alkyl heteromonocycle)amino... Specific Chemical Substances § 721.2094 N,N′-di(alkyl heteromonocycle)amino chlorotriazine. (a) Chemical... as N,N′-di(alkyl heteromonocycle)amino chlorotriazine (PMN P-93-1369) is subject to reporting...

  20. 40 CFR 721.2094 - N,N′-di(alkyl heteromonocycle)amino chlorotriazine.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false N,Nâ²-di(alkyl heteromonocycle)amino... Specific Chemical Substances § 721.2094 N,N′-di(alkyl heteromonocycle)amino chlorotriazine. (a) Chemical... as N,N′-di(alkyl heteromonocycle)amino chlorotriazine (PMN P-93-1369) is subject to reporting...

  1. 40 CFR 721.2094 - N,N′-di(alkyl heteromonocycle)amino chlorotriazine.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false N,Nâ²-di(alkyl heteromonocycle)amino... Specific Chemical Substances § 721.2094 N,N′-di(alkyl heteromonocycle)amino chlorotriazine. (a) Chemical... as N,N′-di(alkyl heteromonocycle)amino chlorotriazine (PMN P-93-1369) is subject to reporting...

  2. 40 CFR 721.2094 - N,N′-di(alkyl heteromonocycle)amino chlorotriazine.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false N,Nâ²-di(alkyl heteromonocycle)amino... Specific Chemical Substances § 721.2094 N,N′-di(alkyl heteromonocycle)amino chlorotriazine. (a) Chemical... as N,N′-di(alkyl heteromonocycle)amino chlorotriazine (PMN P-93-1369) is subject to reporting...

  3. URINARY METABOLITES OF DI-N-OCTYL PHTHALATE IN RATS

    EPA Science Inventory

    Di-n-octyl phthalate (DnOP) is a plasticizer used in polyvinyl chloride plastics, cellulose esters, and polystyrene resins. The metabolism of DnOP results in the hydrolysis of one ester linkage to produce mono-n-octyl phthalate (MnOP), which subsequently metabolizes to form oxida...

  4. PLCs, DI, & RTI: A Tapestry for School Change

    ERIC Educational Resources Information Center

    Stoehr, Judy; Banks, Maria; Allen, Linda

    2011-01-01

    Rather than buying individual books about professional learning communities (PLCs), differentiated instruction (DI), and Response to Intervention (RTI), invest wisely in one resource that synthesizes all three. The text uses a tapestry analogy to weave together these critical topics to form a comprehensive framework for achieving continuous school…

  5. 21 CFR 178.3940 - Tetraethylene glycol di-(2-ethylhexoate).

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Tetraethylene glycol di-(2-ethylhexoate). 178.3940 Section 178.3940 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION (CONTINUED) INDIRECT FOOD ADDITIVES: ADJUVANTS, PRODUCTION AIDS, AND SANITIZERS Certain Adjuvants...

  6. 21 CFR 178.3940 - Tetraethylene glycol di-(2-ethylhexoate).

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Tetraethylene glycol di-(2-ethylhexoate). 178.3940 Section 178.3940 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) FOOD FOR HUMAN CONSUMPTION (CONTINUED) INDIRECT FOOD ADDITIVES: ADJUVANTS, PRODUCTION AIDS, AND SANITIZERS Certain Adjuvants...

  7. TOXICOLOGY OF MONO- AND DI-ALKYLTIN CHLORIDES.

    EPA Science Inventory

    Mono- and di-alkyltin chlorides are reactive compounds used in the production of stabilizers for polyvinyl chloride (PVC) plastics, primarily used for water distribution pipes. Health effects data were compiled or developed by the manufacturers for the EPA's HPV Challenge progra...

  8. TOXICOLOGY OF MONO- AND DI-ALKYLTIN CHLORIDES

    EPA Science Inventory

    Mono- and di-alkyltin chlorides are reactive compounds used in the production of stabilizers for polyvinyl chloride (PVC) plastics, primarily used for water distribution pipes. Health effects data were compiled or developed by the manufacturers for the EPA's HPV Challenge progra...

  9. "DI Days:" Differentiating Instruction through Student Choice. Classroom Tips

    ERIC Educational Resources Information Center

    Hammond, Donald J.

    2011-01-01

    To better meet the needs of the author's high school students, who have a variety of abilities, interests and engagement levels, he often differentiates instruction through the use of "DI Days." On these days, students use a choice board to select from a wide range of activities offered in learning centers. Each center offers content-focused

  10. "DI Days:" Differentiating Instruction through Student Choice. Classroom Tips

    ERIC Educational Resources Information Center

    Hammond, Donald J.

    2011-01-01

    To better meet the needs of the author's high school students, who have a variety of abilities, interests and engagement levels, he often differentiates instruction through the use of "DI Days." On these days, students use a choice board to select from a wide range of activities offered in learning centers. Each center offers content-focused…

  11. Clinical Phenotype of DiGeorge Syndrome with Negative Genetic Tests: A Case of DiGeorge-Like Syndrome?

    PubMed Central

    Laccetta, Gianluigi; Toschi, Benedetta; Fogli, Antonella; Bertini, Veronica; Valetto, Angelo; Consolini, Rita

    2015-01-01

    We report a case of DiGeorge-like syndrome in which immunodeficiency coexisting with juvenile idiopathic arthritis, congenital heart disease, delay in emergence of language and in motor milestones, feeding and growing problems, enamel hypoplasia, mild skeletal anomalies, and facial dysmorphisms are associated with no abnormalities found on genetic tests. PMID:26793401

  12. Late Pleistocene climatic variations as recorded in two Italian maar lakes (Lago di Mezzano, Lago Grande di Monticchio)

    NASA Astrophysics Data System (ADS)

    Ramrath, Antje; Zolitschka, Bernd; Wulf, Sabine; Negendank, Jörg F. W.

    1999-06-01

    Sediment profiles from two maar lakes, Lago di Mezzano (central Italy) and Lago Grande di Monticchio (southern Italy), were investigated with respect to their minerogenic and biogenic sediment accumulation rates for a time window spanning the final 20,000 yr of the last glaciation. The chronological framework is provided by calibrated radiocarbon ages, varve counting, calculation of sedimentation rates and tephrochronology. In the time slice between 34,000 and 14,000 cal BP periods of increased minerogenic input are observed in both lacustrine records, interrupted by periods of low minerogenic input. These cyclic variations have an average recurrence time of 1785 yr for Lago di Mezzano and 2875 yr for Lago Grande di Monticchio, comparing well with marine and ice core data. Explanations for these pulses of increased minerogenic sedimentation include enhanced erosion and runoff. The higher precipitation/evaporation ratio required for this interpretation was possibly restricted to winter months as earlier published pollen analyses on sediments from Lago Grande di Monticchio show a contemporary development of steppe vegetation, an indicator for cool/dry climatic conditions. This may be connected with a southward shift of the westerlies and a reinforced jet stream. Agreement of lacustrine data from Italy with late Pleistocene glacial events in central Italy, with events recorded in marine archives from the North Atlantic (Heinrich events) and with oxygen isotope data from Greenland ice cores is interpreted as evidence for the Late Pleistocene climate in Europe being influenced by North Atlantic climatic forcing which may be related to Dansgaard-Oeschger cycles.

  13. Photodegradation of polymer-dispersed perylene di-imide dyes

    NASA Astrophysics Data System (ADS)

    Tanaka, Nobuaki; Barashkov, Nikolay; Heath, Jerry; Sisk, Wade N.

    2006-06-01

    Polymer-dispersed perylene di-imide dye photodegradation is investigated by monitoring the fluorescence intensity as a function of 532 nm laser pulses. Anaerobically irradiated polymer-dye films exhibited an accelerated decrease in fluorescence intensity, which was partially recovered upon exposure to oxygen. Decelerated photodegradation rates were observed for perylene di-imide ethanol solutions upon the addition of a singlet oxygen quenching antioxidant. These observations suggest reversible photoreduction and type II photo-oxidation as important photodegradation mechanisms. Type II photo-oxidation for perylene red 532 nm irradiation is supported by a singlet oxygen quantum yield of 0.09±0.03, determined via detection of time-resolved O2 (a1Δg —> X3∑g-) infrared phosphorescence.

  14. [Dr Lorenzo Dojmi di Delupis- the "Leopard" from Vis].

    PubMed

    Jamnicki Dojmi, Mirko

    2011-01-01

    Dr Lorenzo Dojmi di Delupis (1845-1927) was a descendant of a respectful aristocratic family from Vis. His father was Peter Dojmi di Delupis (1809-1886), an attorney, a moderate pro-Italian autonomist, and a mayor of Vis, and his mother was Margherita Siminati. As soon as he graduated from the Medical University of Graz in 1870, he joined the Ottoman army as a physician for a two-year journey in which he reached as far as Baghdad and Basra. He left notes about this dramatic, juvenile adventure in his diaries. In 1878, he married a Viennese girl Maria Neidl and brought her home to Vis, where he got a position of municipal doctor. He had an extraordinary diagnosing acuity, great sympathy for patients, and was always willing to help, which is why he was adored by all the people of Vis, whether they agreed with his autonomist ideas or not, and soon became "the father of Vis". He was the first to warn of leprosy in Dalmatia, when he diagnosed two cases in Vis. Beside medicine and politics, he was also a passionate botanist. He was the first to seed palms in Vis and to grow a palm nursery with his agronomist son Peter Dojmi, for the whole of Dalmatia. He also tried breeding ostriches and growing Mexican coffee. He funded a small meteorological station in Vis, and planned to open a health resort with professor Schröter from Vienna. Even though Lorenzo Dojmi di Delupis held the great Italian culture very dear, his vocation as a physician and humanist inclination never let him burn with the fervour of a political extremist. Thanks to his psychophysical stability, he overcame numerous difficulties in life and retained faith in people. All these traits evoke Prince Salina, the leading character of the renowned novel Il gattopardo (The Leopard) by Giuseppe Tomasi di Lampedusa, which is why the author has so entitled this article "The Gattopardo of Vis". PMID:22292541

  15. The di-heme family of respiratory complex II enzymes.

    PubMed

    Lancaster, C Roy D

    2013-05-01

    The di-heme family of succinate:quinone oxidoreductases is of particular interest, because its members support electron transfer across the biological membranes in which they are embedded. In the case of the di-heme-containing succinate:menaquinone reductase (SQR) from Gram-positive bacteria and other menaquinone-containing bacteria, this results in an electrogenic reaction. This is physiologically relevant in that it allows the transmembrane electrochemical proton potential Δp to drive the endergonic oxidation of succinate by menaquinone. In the case of the reverse reaction, menaquinol oxidation by fumarate, catalysed by the di-heme-containing quinol:fumarate reductase (QFR), evidence has been obtained that this electrogenic electron transfer reaction is compensated by proton transfer via a both novel and essential transmembrane proton transfer pathway ("E-pathway"). Although the reduction of fumarate by menaquinol is exergonic, it is obviously not exergonic enough to support the generation of a Δp. This compensatory "E-pathway" appears to be required by all di-heme-containing QFR enzymes and results in the overall reaction being electroneutral. In addition to giving a brief overview of progress in the characterization of other members of this diverse family, this contribution summarizes key evidence and progress in identifying constituents of the "E-pathway" within the framework of the crystal structure of the QFR from the anaerobic epsilon-proteobacterium Wolinella succinogenes at 1.78Å resolution. This article is part of a Special Issue entitled: Respiratory complex II: Role in cellular physiology and disease. PMID:23466335

  16. URINARY AND AMNIOTIC FLUID LEVELS OF PHTHALATE MONOESTERS IN RATS AFTER THE ORAL ADMINISTRATION OF DI(2-ETHYLHEXYL) PHTHALATE AND DI-N-BUTYL PHTHALATE

    EPA Science Inventory

    Two studies were designed to examine amniotic fluid and maternal urine concentrations of the di(2-ethylhexyl) phthalate (DEHP) metabolite mono(2-ethylhexyl) phthalate (MEHP) and the di-n-butyl phthalate (DBP) metabolite monobutyl phthalate (MBP) after administration of DEHP and D...

  17. Di-n-butyl Phthalate (DNBP) and Diisobutyl Phthalate (DiBP) Metabolism in a Human Volunteer after Single Oral Doses [Journal Article

    EPA Science Inventory

    An individual (male, 36 years, 87 kg) ingested two separate doses of di-n-butyl phthalate (DnBP) and diisobutyl phthalate (DiBP) at a rate of ~60 g/kg. Key monoester and oxidized metabolites were identified and quantified in urine continuously collected until 48 hours post dos...

  18. Di-n-butyl Phthalate (DNBP) and Diisobutyl Phthalate (DiBP) Metabolism in a Human Volunteer after Single Oral Doses [Journal Article

    EPA Science Inventory

    An individual (male, 36 years, 87 kg) ingested two separate doses of di-n-butyl phthalate (DnBP) and diisobutyl phthalate (DiBP) at a rate of ~60 µg/kg. Key monoester and oxidized metabolites were identified and quantified in urine continuously collected until 48 hours post dos...

  19. 40 CFR 721.10325 - Cyclosilazanes, di-Me, Me hydrogen, polymers with di-Me, Me hydrogen silazanes, reaction products...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ..., polymers with di-Me, Me hydrogen silazanes, reaction products with 3-(triethoxysilyl)-1-propanamine. 721..., reaction products with 3-(triethoxysilyl)-1-propanamine. (a) Chemical substance and significant new uses..., polymers with di-Me, Me hydrogen silazanes, reaction products with 3-(triethoxysilyl)-1-propanamine (PMN...

  20. 40 CFR 721.10325 - Cyclosilazanes, di-Me, Me hydrogen, polymers with di-Me, Me hydrogen silazanes, reaction products...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ..., polymers with di-Me, Me hydrogen silazanes, reaction products with 3-(triethoxysilyl)-1-propanamine. 721..., reaction products with 3-(triethoxysilyl)-1-propanamine. (a) Chemical substance and significant new uses..., polymers with di-Me, Me hydrogen silazanes, reaction products with 3-(triethoxysilyl)-1-propanamine (PMN...

  1. DiGeorge syndrome with vertebral and rib dysplasia

    SciTech Connect

    Puno-Cocuzza, C.; David, K.; Kogekar, N.

    1994-09-01

    DiGeorge syndrome results from defect in the development of the third and fourth pharyngeal pouches, and is characterized by conotruncal heart defects, aplasia or hypoplasia of thymus and parathyroid glands resulting in immune deficiency and hypocalcemia. Other associated abnormalities include renal, thyroid and diaphragmatic defects, oral clefting, etc. Etiologically, it is heterogeneous, with a microdeletion of 22q11 present in over 80% of cases. Our patient was born following a pregnancy complicated by insulin dependent gestational diabetes. There was truncus arteriosus type 2, absense of thymic shadow on CXR with severe deficiency of T cell function, and persistent hypocalcemia with low parathormone. Right kidney was absent. Dysplastic ribs including fused and bifid ribs were noted. Hypoplastic vertebrae and hemivertebrae were present through thoracic and lumbar regions. Chromosome analysis was normal, and metaphase FISH analysis with probe N25 representing locus D22S75 did not show any deletion of 22q11.2. The skeletal findings similar to these have not been previously reported in association with DiGeorge syndrome to our knowledge. Vertebral and rib abnormalities are known to occur with pregestational maternal diabetes. Maternal diabetes has also been suggested to be a possible etiology in a very small proportion of DiGeorge syndrome cases. It is possible that these findings occured together on account of gestational maternal diabetes in our case.

  2. Complexation of di-amides of dipicolinic acid with neodymium

    SciTech Connect

    Lapka, J.L.; Paulenova, A.

    2013-07-01

    Di-amides have undergone significant studies as possible ligands for use in the partitioning of trivalent minor actinides and lanthanides. The binding affinities of three isomeric ligands with neodymium in acetonitrile solution have been investigated. The stability constants of the metal-ligand complexes formed between different isomers of N,N'-diethyl-N,N'- ditolyl-di-picolinamide (EtTDPA) and trivalent neodymium in acetonitrile have been determined by spectrophotometric and calorimetric methods. Each isomer of EtTDPA has been found to be capable of forming three complexes with trivalent neodymium, Nd(EtTDPA), Nd(EtTDPA){sub 2}, and Nd(EtTDPA){sub 3}. Values from spectrophotometric and calorimetric titrations are within reasonable agreement with each other. The order of stability constants for each metal:ligand complex decreases in the order Et(m)TDPA > Et(p)TDPA > Et(o)TDPA. The obtained values are comparable to other di-amidic ligands obtained under similar system conditions and mirror previously obtained solvent extraction data for EtTDPA at low ionic strengths. (authors.

  3. Di(hydroxyphenyl)- 1,2,4-triazole monomers

    NASA Technical Reports Server (NTRS)

    Connell, John W. (Inventor); Hergenrother, Paul M. (Inventor); Wolf, Peter (Inventor)

    1993-01-01

    The di(hydroxyphenyl)- 1,2,4-triazole monomers were first synthesized by reacting bis (4-hydroxyphenyl) hydrazide with aniline hydrochloride at 250 C in the melt and also by reacting 1,3 or 1,4-bis- (4-hydroxyphenyl)- phenylene- dihydrazide with 2 moles of aniline hydrochloride in the melt. Purification of the di(hydroxyphenyl)- 1,2,4-triazole monomers was accomplished by recrystallization. Poly (1,2,4-triazoles) (PT) were prepared by the aromatic nucleophilic displacement reaction of di(hydroxyphenyl)- 1,2,4-triazole monomers with activated aromatic dihalides or activated aromatic dinitro compounds. The reactions were carried out in polar aprotic solvents such as sulfolane or diphenylsulfone using alkali metal bases such as potassium carbonate at elevated temperatures under nitrogen. This synthetic route has provided high molecular weight PT of new chemical structure, is economically and synthetically more favorable than other routes, and allows for facile chemical structure variation due to the availability of a large variety of activated aromatic dihalides.

  4. (Di-methyl-phosphor-yl)methanaminium iodide-(di-methyl-phosphor-yl)methan-amine (1/1).

    PubMed

    Reiss, Guido J

    2013-01-01

    The asymmetric unit of the title structure, C3H11NOP(+)·I(-)·C3H10NOP, consists of one (di-methyl-phosphor-yl)methanamine (dpma) mol-ecule, one (di-methyl-phosphor-yl)methanaminium (dpmaH) ion and one iodide counter-anion. In the crystal, medium-strong to weak N-H⋯O and N-H⋯N hydrogen bonds connect dpmaH cations and dpma mol-ecules into strands along [001]. The iodide counter-anions form only very weak hydrogen bonds. The crystal used for the diffraction study was found to be an inversion twin with a ratio of 0.83 (2):0.17 (2). The title structure is isotypic to that of dpmaH[ClO4]·dpma [Buhl et al. (2013 ▶). Crystals 3, 350-362]. PMID:24109340

  5. [La scuola di psicoterapia post-razionalista oggi: ricerca e pratica clinica].

    PubMed

    De Pascale, Adele; Quiñones, Álvaro; Cimbolli, Paola

    2016-01-01

    RIASSUNTO. La scuola di psicoterapia post-razionalista (approccio cognitivista non classico) ha avuto inizio alla fine degli anni Ottanta con una serie di ipotesi coerenti e scientificamente attendibili. È una scuola che prende l'avvio dalla psicoterapia contemporanea e si sviluppa in aree differenti, offrendo un notevole contributo alla teoria e alla clinica della psicoterapia. Tale scuola ha avuto nel corso degli anni i suoi sviluppi, al pari di tutte le altre scuole di psicoterapia, come pure le stesse difficoltà e capacità di trovare soluzioni. In questo articolo, nostro scopo è quello di illustrare alcune tendenze che non presentano una coerenza epistemologica, teorica e metodologica e non consentono alcuna confutazione, cosa invece fondamentale nelle premesse della scuola iniziata da Vittorio Guidano. Infine, sottolineiamo come sia fondamentale oggi in psicoterapia applicare metodologie coerenti e posizioni concettuali basate sulla ricerca. PMID:27030344

  6. Effects of di-iso-butyl phthalate on testes of prepubertal rats and mice.

    PubMed

    Zhu, Xiao Bo; Tay, Tat Wei; Andriana, Bibin Bintang; Alam, Mohammad Shah; Choi, Ehn Kyoung; Tsunekawa, Naoki; Kanai, Yoshiakira; Kurohmaru, Masamichi

    2010-02-01

    Di-iso-butyl phthalate (DiBP), a special plasticizer, is used as a substitute for di(n-butyl) phthalate (DBP). The effects of DiBP on testes in prepubertal rodents still remain to be obscure. Testicular toxicity of DiBP was investigated in 21-day-old Sprague-Dawley rats and C57BL/6N mice, using with in situ TUNEL method. For an acute exposure experiment, animals were once given DiBP at various concentrations by oral gavage. For a subchronic exposure experiment, they were daily given DiBP at various concentrations for consecutive 7 days. Controls were treated with corn oil under the same condition. For a recovery experiment, rats were once given DiBP (1000 mg/kg), and were sacrificed at day 1 to 8 after administration. Furthermore, the disorder of vimentin filaments in Sertoli cells after daily administration of DiBP (500 mg/kg) for consecutive 7 days in rats also identified by immunohistochemistry using anti-vimentin antibody. As a result, the present study demonstrated that DiBP can induce testicular atrophy in rats due to the increase of TUNEL-positive spermatogenic cells in both acute and subchronic exposure experiments. At the same time, the disorder of vimentin filaments in Sertoli cells was recognized. However, no such damages could be found in mouse testis. For the recovery experiment, the testis weight and testicular morphology returned to normal at day 6 after administration. In conclusion, the present study indicates that DiBP causes the significant increase of TUNEL-positive spermatogenic cells and the disorder of vimentin filaments in Sertoli cells in rats and that DiBP shows a species-specific toxicity. PMID:20560449

  7. Cyclic Di-GMP Riboswitch-Regulated Type IV Pili Contribute to Aggregation of Clostridium difficile

    PubMed Central

    Bordeleau, Eric; Purcell, Erin B.; Lafontaine, Daniel A.; Fortier, Louis-Charles; Tamayo, Rita

    2014-01-01

    Clostridium difficile is an anaerobic Gram-positive bacterium that causes intestinal infections with symptoms ranging from mild diarrhea to fulminant colitis. Cyclic diguanosine monophosphate (c-di-GMP) is a bacterial second messenger that typically regulates the switch from motile, free-living to sessile and multicellular behaviors in Gram-negative bacteria. Increased intracellular c-di-GMP concentration in C. difficile was recently shown to reduce flagellar motility and to increase cell aggregation. In this work, we investigated the role of the primary type IV pilus (T4P) locus in c-di-GMP-dependent cell aggregation. Inactivation of two T4P genes, pilA1 (CD3513) and pilB1 (CD3512), abolished pilus formation and significantly reduced cell aggregation under high c-di-GMP conditions. pilA1 is preceded by a putative c-di-GMP riboswitch, predicted to be transcriptionally active upon c-di-GMP binding. Consistent with our prediction, high intracellular c-di-GMP concentration increased transcript levels of T4P genes. In addition, single-round in vitro transcription assays confirmed that transcription downstream of the predicted transcription terminator was dose dependent and specific to c-di-GMP binding to the riboswitch aptamer. These results support a model in which T4P gene transcription is upregulated by c-di-GMP as a result of its binding to an upstream transcriptionally activating riboswitch, promoting cell aggregation in C. difficile. PMID:25512308

  8. In vitro selection of allosteric ribozymes that sense the bacterial second messenger c-di-GMP.

    PubMed

    Furukawa, Kazuhiro; Gu, Hongzhou; Breaker, Ronald R

    2014-01-01

    Recently, a number of study have shown the ligand-dependent allosteric ribozymes can be harnessed as biosensors, high-throughput screening, and agents for the control of gene expression in vivo, called artificial riboswitches. In this chapter, we describe how in vitro selection can be used to create an allosteric ribozyme that senses bacterial second messenger cyclic-di-GMP (c-di-GMP). A hammerhead ribozyme was joined to a natural c-di-GMP class I riboswitch aptamer via communication modules. Both c-di-GMP-activating and -inhibiting ribozyme can be obtained by this approach. PMID:24549622

  9. Structural Basis of Ligand Binding by a C-di-GMP Riboswitch

    SciTech Connect

    Smith, K.; Lipchock, S; Ames, T; Wang, J; Breaker, R; Strobel, S

    2009-01-01

    The second messenger signaling molecule bis-(3{prime}-5{prime})-cyclic dimeric guanosine monophosphate (c-di-GMP) regulates many processes in bacteria, including motility, pathogenesis and biofilm formation. c-di-GMP-binding riboswitches are important downstream targets in this signaling pathway. Here we report the crystal structure, at 2.7 {angstrom} resolution, of a c-di-GMP riboswitch aptamer from Vibrio cholerae bound to c-di-GMP, showing that the ligand binds within a three-helix junction that involves base-pairing and extensive base-stacking. The symmetric c-di-GMP is recognized asymmetrically with respect to both the bases and the backbone. A mutant aptamer was engineered that preferentially binds the candidate signaling molecule c-di-AMP over c-di-GMP. Kinetic and structural data suggest that genetic regulation by the c-di-GMP riboswitch is kinetically controlled and that gene expression is modulated through the stabilization of a previously unidentified P1 helix, illustrating a direct mechanism for c-di-GMP signaling.

  10. Crystal structure of di-aqua-bis-(2,6-di-methyl-pyrazine-κN (4))bis-(thio-cyanato-κN)cobalt(II) 2,5-di-methyl-pyrazine monosolvate.

    PubMed

    Suckert, Stefan; Wöhlert, Susanne; Jess, Inke; Näther, Christian

    2015-12-01

    In the crystal structure of the title compound, [Co(NCS)2(C6H8N2)2(H2O)2]·C6H8N2, the Co(II) cation is coordinated by the N atoms of two terminal thio-cyanate anions, the O atoms of two water mol-ecules and two N atoms of two 2,6-di-methyl-pyrazine ligands. The coordination sphere of the resulting discrete complex is that of a slightly distorted octa-hedron. The asymmetric unit comprises a Co(II) cation and half of a 2,5-di-methyl-pyrazine ligand, both of which are located on centres of inversion, and a water ligand, a 2,6-di--methyl-pyrazine ligand and one thio-cyanate anion in general positions. In the crystal, the discrete complexes are arranged in such a way that cavities are formed in which the 2,5-di-methyl-pyrazine solvent mol-ecules are located. The coordination of the 2,5-di-methyl-pyrazine mol-ecules to the metal is apparently hindered due to the bulky methyl groups in vicinal positions to the N atoms, leading to a preferential coordination of the 2,6-di-methyl-pyrazine ligands. The discrete complexes are linked by O-H⋯N hydrogen bonds between one water H atom and the non-coordinating N atom of the 2,6-di-methyl-pyrazine ligands. The remaining water H atom is hydrogen bonded to one N atom of the 2,5-di-methyl-pyrazine solvent mol-ecule. This arrangement leads to the formation of a two-dimensional network extending parallel to (010). PMID:26870445

  11. The Hydrolysis of Di-Isopropyl Methylphosphonate in Ground Water

    SciTech Connect

    Sega, G.A., Tomkins, B.A., Griest, W.H., Bayne, C.K.

    1997-12-31

    Di-isopropyl methylphosphonate (DIMP) is a byproduct from the manufacture of the nerve agent Sarin. The persistence of DIMP in the ground water is an important question in evaluating the potential environmental impacts of DIMP contamination. The half-life of DIMP in ground water at 10 deg C was estimated to be 500 years with a 95% confidence interval of 447 to 559 years from measurements of the hydrolysis rates at temperatures between 70 to 98 deg C.Extrapolation of the kinetics to 10 deg C used the Arrhenius equation, and calculation of the half-life assumed first-order kinetics. Inorganic phosphate was not detected.

  12. Bis(benzyl­ammonium) di­hydrogen diphosphate

    PubMed Central

    Saad, Ahlem Ben; Elboulali, Adel; Ratel-Ramond, Nicolas; Mohamed, Rzaigui; Toumi, Samah Akriche

    2014-01-01

    The asymmetric unit of the title salt, 2C6H5CH2NH3 +·H2P2O7 2−, contains two independent benzyl­ammonium cations and a di­hydrogen diphosphate dianion. In the crystal, O—H⋯O and N—H⋯O hydrogen bonds link the cations and anions, forming a two-dimensional network parallel to (010). Within this network, weak C—H⋯O hydrogen bonds are observed. PMID:24526977

  13. Crystal structure of 3-(di-ethyl-amino)-phenol.

    PubMed

    Golen, James A; McDonald, Kyle J; Manke, David R

    2015-12-01

    The title compound, C10H15NO, has two mol-ecules in the asymmetric unit. Each mol-ecule has a near-planar C8NO unit excluding H atoms and the terminal methyl groups on the di-ethyl-amino groups, with mean deviations from planarity of 0.036 and 0.063?. In the crystal, hydrogen bonding leads to four-membered O-H?O-H?O-H rings. No ?-? inter-actions were observed in the structure. PMID:26870505

  14. Gelling Mechanism of Aluminum Di-Soaps in Oils

    NASA Astrophysics Data System (ADS)

    Wang, Xiaorong; Rackaitis, Mindaugas

    2009-03-01

    This work demonstrates that aluminum di-soaps form nano-sized spherical micelles in the oils and that the aggregation of these micelles forms a network that gives rise to a gel formation -- thereby refuting a long-held belief that the gel formation was the result of linear polymeric chains of aluminum association. The discovery of such aluminum nano-particles could expand application of these materials to new technologies because these materials are chemically inert, odorless and nontoxic, and have been widely used in greases, paints, gels, cosmetics, drugs and foods.

  15. Line plotting program using DI-3000/Grafmaker routines

    NASA Technical Reports Server (NTRS)

    Poppen, William A., Jr.; Smith-Taylor, Rudeen

    1986-01-01

    A line plotting program has been developed using the DI-3000 graphics libraries and incorporates Grafmaker subroutines. The program allows multiple lines on a frame and multiple frames per run. Options such as automatic scaling, linear or single-cycle log graphs, and plot text such as titles, legends and axis labels are incorporated in the program. Greek and other fonts can be used in the plot text as well as upper and lower case text. Plot inputs are specified through a control file. The program also allows display of multiple independent data sets on a single graph.

  16. Synthesis and study of conjugated polymers containing Di- or Triphenylamine

    SciTech Connect

    Sukwattanasinitt, M.

    1996-06-21

    This thesis consists of two separate parts. The first part addresses the synthesis and study of conjugated polymers containing di- or triphenylamine. Two types of polymers: linear polymers and dendrimers, were synthesized. The polymers were characterized by NMR, IR, UV, GPC, TGA and DSC. Electronic and optical properties of the polymers were studied through the conductivity measurements and excitation- emission spectra. the second part of this thesis deals with a reaction of electron-rich acetylenes with TCNE. The discovery of the reaction from charge transfer complex studies and the investigation of this reaction on various electron-rich acetylenes are presented.

  17. Crystal structure of di-aqua-bis-(2,6-di-methyl-pyrazine-κN)bis-(thio-cyanato-κN)cobalt(II) 2,5-di-methyl-pyrazine tris-olvate.

    PubMed

    Suckert, Stefan; Wöhlert, Susanne; Jess, Inke; Näther, Christian

    2015-12-01

    In the crystal structure of the title compound, [Co(NCS)2(C6H8N2)2(H2O)2]·3C6H8N2, the Co(II) cation is coordinated by two terminally N-bound thio-cyanate anions, two water mol-ecules and two 2,6-di-methyl-pyrazine ligands, forming a discrete complex with a slightly distorted octa-hedral N4O2 coordination environment. The asymmetric unit contains one Co(II) cation and three halves of 2,5-di-methyl-pyrazine solvate mol-ecules, all entities being completed by inversion symmetry, as well as one thio-cyanate anion, an aqua ligand and a 2,6-di-methyl-pyrazine ligand, all in general positions. In the crystal, discrete complexes are arranged in a way that cavities are formed where the noncoordinating 2,5-di-methyl-pyrazine mol-ecules are located. The coordination of the latter to the metal is prevented due to the bulky methyl groups in vicinal positions to the N atoms, leading to a preferential coordination through the 2,6-di-methyl-pyrazine ligands. The complex mol-ecules are linked by O-H⋯N hydrogen bonds between the water H atoms and the N atoms of 2,5-di-methyl-pyrazine solvent mol-ecules, leading to a layered structure extending parallel to (100). PMID:26870459

  18. Occurrence of Cyclic di-GMP-Modulating Output Domains in Cyanobacteria: an Illuminating Perspective

    PubMed Central

    Agostoni, Marco; Koestler, Benjamin J.; Waters, Christopher M.; Williams, Barry L.; Montgomery, Beronda L.

    2013-01-01

    ABSTRACT Microorganisms use a variety of metabolites to respond to external stimuli, including second messengers that amplify primary signals and elicit biochemical changes in a cell. Levels of the second messenger cyclic dimeric GMP (c-di-GMP) are regulated by a variety of environmental stimuli and play a critical role in regulating cellular processes such as biofilm formation and cellular motility. Cyclic di-GMP signaling systems have been largely characterized in pathogenic bacteria; however, proteins that can impact the synthesis or degradation of c-di-GMP are prominent in cyanobacterial species and yet remain largely underexplored. In cyanobacteria, many putative c-di-GMP synthesis or degradation domains are found in genes that also harbor light-responsive signal input domains, suggesting that light is an important signal for altering c-di-GMP homeostasis. Indeed, c-di-GMP-associated domains are often the second most common output domain in photoreceptors—outnumbered only by a histidine kinase output domain. Cyanobacteria differ from other bacteria regarding the number and types of photoreceptor domains associated with c-di-GMP domains. Due to the widespread distribution of c-di-GMP domains in cyanobacteria, we investigated the evolutionary origin of a subset of genes. Phylogenetic analyses showed that c-di-GMP signaling systems were present early in cyanobacteria and c-di-GMP genes were both vertically and horizontally inherited during their evolution. Finally, we compared intracellular levels of c-di-GMP in two cyanobacterial species under different light qualities, confirming that light is an important factor for regulating this second messenger in vivo. PMID:23943760

  19. C-E1 fusion protein synthesized by rubella virus DI RNAs maintained during serial passage

    SciTech Connect

    Tzeng, W.-P.; Frey, Teryl K. . E-mail: tfrey@gsu.edu

    2006-12-20

    Rubella virus (RUB) replicons are derivatives of the RUB infectious cDNA clone that retain the nonstructural open reading frame (NS-ORF) that encodes the replicase proteins but not the structural protein ORF (SP-ORF) that encodes the virion proteins. RUB defective interfering (DI) RNAs contain deletions within the SP-ORF and thus resemble replicons. DI RNAs often retain the 5' end of the capsid protein (C) gene that has been shown to modulate virus-specific RNA synthesis. However, when replicons either with or without the C gene were passaged serially in the presence of wt RUB as a source of the virion proteins, it was found that neither replicon was maintained and DI RNAs were generated. The majority DI RNA species contained in-frame deletions in the SP-ORF leading to a fusion between the 5' end of the C gene and the 3' end of the E1 glycoprotein gene. DI infectious cDNA clones were constructed and transcripts from these DI infectious cDNA clones were maintained during serial passage with wt RUB. The C-E1 fusion protein encoded by the DI RNAs was synthesized and was required for maintenance of the DI RNA during serial passage. This is the first report of a functional novel gene product resulting from deletion during DI RNA generation. Thus far, the role of the C-E1 fusion protein in maintenance of DI RNAs during serial passage remained elusive as it was found that the fusion protein diminished rather than enhanced DI RNA synthesis and was not incorporated into virus particles.

  20. Functional Analysis of a c-di-AMP-specific Phosphodiesterase MsPDE from Mycobacterium smegmatis

    PubMed Central

    Tang, Qing; Luo, Yunchao; Zheng, Cao; Yin, Kang; Ali, Maria Kanwal; Li, Xinfeng; He, Jin

    2015-01-01

    Cyclic di‑AMP (c-di-AMP) is a second signaling molecule involved in the regulation of bacterial physiological processes and interaction between pathogen and host. However, the regulatory network mediated by c-di-AMP in Mycobacterium remains obscure. In M. smegmatis, a diadenylate cyclase (DAC) was reported recently, but there is still no investigation on c-di-AMP phosphodiesterase (PDE). Here, we provide a systematic study on signaling mechanism of c-di-AMP PDE in M. smegmatis. Based on our enzymatic analysis, MsPDE (MSMEG_2630), which contained a DHH-DHHA1 domain, displayed a 200-fold higher hydrolytic efficiency (kcat/Km) to c-di-AMP than to c-di-GMP. MsPDE was capable of converting c-di-AMP to pApA and AMP, and hydrolyzing pApA to AMP. Site-directed mutations in DHH and DHHA1 revealed that DHH domain was critical for the phosphodiesterase activity. To explore the regulatory role of c-di-AMP in vivo, we constructed the mspde mutant (Δmspde) and found that deficiency of MsPDE significantly enhanced intracellular C12-C20 fatty acid accumulation. Deficiency of DAC in many bacteria results in cell death. However, we acquired the M. smegmatis strain with DAC gene disrupted (ΔmsdisA) by homologous recombination approach. Deletion of msdisA reduced bacterial C12-C20 fatty acids production but scarcely affected bacterial survival. We also provided evidences that superfluous c-di-AMP in M. smegmatis could lead to abnormal colonial morphology. Collectively, our results indicate that MsPDE is a functional c-di-AMP-specific phosphodiesterase both in vitro and in vivo. Our study also expands the regulatory network mediated by c-di-AMP in M. smegmatis. PMID:26078723

  1. Crystal structure of 9,10-bis-(1,3-di-thiol-2-yl-idene)-9,10-di-hydro-anthracene.

    PubMed

    Ren, Yi; Lee, Semin; Bertke, Jeffery A; Moore, Jeffrey S

    2015-12-01

    The crystal structure of the well-studied 9,10-bis-(1,3-di-thiol-2-yl-idene)-9,10-di-hydro-anthracene mol-ecule, C20H12S4, (I), also known as exTTF, is reported. The mol-ecular structure of (I) consists of a di-hydro-anthracene moiety with two 1,3-di-thiol-2-yl-idene substituents. This is a saddle-shaped mol-ecule, which inter-acts with a close neighbor through various ?-? and C-H?? contacts to form a 'dimer'. These 'dimers' inter-act through a series of C-H?S and C-H?? contacts to construct a complex three-dimensional extended structure. PMID:26870408

  2. Genetic toxicology testing of di(2-ethylhexyl) terephthalate.

    PubMed

    Barber, E D

    1994-01-01

    Di(2-ethylhexyl) terephthalate (DEHT) is a commercially produced chemical (Kodaflex DOTP) that is used as a general purpose, low-volatility plasticizer for polyvinyl chloride and other polymeric materials. Less than 30 million kilograms of DEHT are produced annually. DEHT is isomeric with di(2-ethylhexyl) phthalate (DEHP), a nongenotoxic rodent carcinogen whose mode of action has been suggested to derive from its ability to produce hepatocellular proliferation and/or hepatic peroxisome proliferation. Thus it is important to know the behavior of DEHT in genotoxicity assays in order to compare it with that of DEHP and other phthalate ester plasticizers. It is known from previously published studies that rats fed DEHT in the diet at 2,000 mg/kg produce urine that is negative in the Ames Salmonella bacterial mutagenicity assay in the presence and absence of induced rat liver S-9 and in the presence and absence of beta-glucuronidase/aryl sulfatase. Reported here are the results of direct testing of DEHT in the Ames plate incorporation assay, the Chinese hamster ovary/hypoxanthine guanine phosphoribosyl transferase (CHO/HGPRT) in vitro mammalian cell mutagenicity assay, and an in vitro chromosome aberrations assay using CHO cells. The results for mono(ethylhexyl) terephthalate (MEHT), a metabolite of DEHT, in the Ames Salmonella bacterial mutagenicity assay are also presented. All test results for both DEHT and MEHT were found to be negative, and it is therefore concluded that DEHT, like its isomeric relative DEHP, is not genotoxic. PMID:8162897

  3. Critical cleaning agents for Di-2-ethylhexyl sebacate.

    SciTech Connect

    Hartley, Mya; Archuleta, Kim M.

    2013-08-01

    It is required that Di-2-ethylhexyl Sebacate oil, also commonly known as Dioctyl Sebacate oil, be thoroughly removed from certain metals, in this case stainless steel parts with narrow, enclosed spaces. Dioctyl Sebacate oil is a synthetic oil with a low compressibility. As such, it is ideally used for high pressure calibrations. The current method to remove the Dioctyl Sebacate from stainless steel parts with narrow, enclosed spaces is a labor-intensive, multi-step process, including a detergent clean, a deionized (DI) water rinse, and several solvent rinses, to achieve a nonvolatile residue of0.04 mg per 50 mL rinse effluent. This study was undertaken to determine a superior detergent/solvent cleaning method for the oil to reduce cleaning time and/or the amount of detergent/solvent used. It was determined that while some detergent clean the oil off the metal better than the current procedure, using only solvents obtained the best result. In addition, it can be inferred, based on elevated temperature test results, that raising the temperature of the oil-contaminated stainless steel parts to approximately 50%C2%B0C will provide for improved cleaning efficacy.

  4. RATE CONSTANTS FOR THE REACTIONS OF OH RADICALS AND CL ATOMS WITH DI-N-PROPYL ETHER AND DI-N-BUTYL ETHER AND THEIR DEUTERATED ANALOGS. (R825252)

    EPA Science Inventory

    Using relative rate methods, rate constants for the gas-phase reactions of OH radicals and Cl atoms with di-n-propyl ether, di-n-propyl ether-d14, di-n-butyl ether and di-n-butyl ether-d18 have been measured at 296 ? 2 K and atmos...

  5. Are There Good Probes for the Di-Neutron Correlation in Light Neutron-Rich Nuclei?

    NASA Astrophysics Data System (ADS)

    Hagino, K.; Sagawa, H.

    2016-03-01

    The di-neutron correlation is a spatial correlation with which two valence neutrons are located at a similar position inside a nucleus. We discuss possible experimental probes for the di-neutron correlation. This includes the Coulomb breakup and the pair transfer reactions of neutron-rich nuclei, and the direct two-neutron decays of nuclei beyond the neutron drip-line.

  6. Contrastive Analysis and Second Language Teaching Today: The Legacy of Robert J. Di Pietro.

    ERIC Educational Resources Information Center

    Danesi, Marcel

    1995-01-01

    Provides a historical overview of the role of Contrastive Analysis (CA) in second-language teaching and discusses Di Pietro's steadfast support of CA. The article concludes with the importance of Di Pietro's notion of strategic interaction, part of his rich legacy to linguistics. (CFM)

  7. c-di-GMP induction of Dictyostelium cell death requires the polyketide DIF-1

    PubMed Central

    Song, Yu; Luciani, Marie-Françoise; Giusti, Corinne; Golstein, Pierre

    2015-01-01

    Cell death in the model organism Dictyostelium, as studied in monolayers in vitro, can be induced by the polyketide DIF-1 or by the cyclical dinucleotide c-di-GMP. c-di-GMP, a universal bacterial second messenger, can trigger innate immunity in bacterially infected animal cells and is involved in developmental cell death in Dictyostelium. We show here that c-di-GMP was not sufficient to induce cell death in Dictyostelium cell monolayers. Unexpectedly, it also required the DIF-1 polyketide. The latter could be exogenous, as revealed by a telling synergy between c-di-GMP and DIF-1. The required DIF-1 polyketide could also be endogenous, as shown by the inability of c-di-GMP to induce cell death in Dictyostelium HMX44A cells and DH1 cells upon pharmacological or genetic inhibition of DIF-1 biosynthesis. In these cases, c-di-GMP–induced cell death was rescued by complementation with exogenous DIF-1. Taken together, these results demonstrated that c-di-GMP could trigger cell death in Dictyostelium only in the presence of the DIF-1 polyketide or its metabolites. This identified another element of control to this cell death and perhaps also to c-di-GMP effects in other situations and organisms. PMID:25518941

  8. 21 CFR 178.2550 - 4-Hydroxymethyl-2,6-di-tert-butylphenol.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... SANITIZERS Antioxidants and Stabilizers § 178.2550 4-Hydroxymethyl-2,6-di-tert-butylphenol. 4-Hydroxymethyl-2,6-di-tert-butyl-phenol may be safely used as an antioxidant in articles intended for use in contact... solidification point of 140°-141 °C. (b) The concentration of the additive and any other permitted...

  9. 21 CFR 178.2550 - 4-Hydroxymethyl-2,6-di-tert-butylphenol.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... SANITIZERS Antioxidants and Stabilizers § 178.2550 4-Hydroxymethyl-2,6-di-tert-butylphenol. 4-Hydroxymethyl-2,6-di-tert-butyl-phenol may be safely used as an antioxidant in articles intended for use in contact... solidification point of 140°-141 °C. (b) The concentration of the additive and any other permitted...

  10. 21 CFR 178.2550 - 4-Hydroxymethyl-2,6-di-tert-butylphenol.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... SANITIZERS Antioxidants and Stabilizers § 178.2550 4-Hydroxymethyl-2,6-di-tert-butylphenol. 4-Hydroxymethyl-2,6-di-tert-butyl-phenol may be safely used as an antioxidant in articles intended for use in contact... solidification point of 140°-141 °C. (b) The concentration of the additive and any other permitted...

  11. 21 CFR 178.2550 - 4-Hydroxymethyl-2,6-di-tert-butylphenol.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... SANITIZERS Antioxidants and Stabilizers § 178.2550 4-Hydroxymethyl-2,6-di-tert-butylphenol. 4-Hydroxymethyl-2,6-di-tert-butyl-phenol may be safely used as an antioxidant in articles intended for use in contact... solidification point of 140°-141 °C. (b) The concentration of the additive and any other permitted...

  12. The cyclic-di-GMP signaling pathway in the Lyme disease spirochete, Borrelia burgdorferi

    PubMed Central

    Novak, Elizabeth A.; Sultan, Syed Z.; Motaleb, Md. A.

    2014-01-01

    In nature, the Lyme disease spirochete Borrelia burgdorferi cycles between the unrelated environments of the Ixodes tick vector and mammalian host. In order to survive transmission between hosts, B. burgdorferi must be able to not only detect changes in its environment, but also rapidly and appropriately respond to these changes. One manner in which this obligate parasite regulates and adapts to its changing environment is through cyclic-di-GMP (c-di-GMP) signaling. c-di-GMP has been shown to be instrumental in orchestrating the adaptation of B. burgdorferi to the tick environment. B. burgdorferi possesses only one set of c-di-GMP-metabolizing genes (one diguanylate cyclase and two distinct phosphodiesterases) and one c-di-GMP-binding PilZ-domain protein designated as PlzA. While studies in the realm of c-di-GMP signaling in B. burgdorferi have exploded in the last few years, there are still many more questions than answers. Elucidation of the importance of c-di-GMP signaling to B. burgdorferi may lead to the identification of mechanisms that are critical for the survival of B. burgdorferi in the tick phase of the enzootic cycle as well as potentially delineate a role (if any) c-di-GMP may play in the transmission and virulence of B. burgdorferi during the enzootic cycle, thereby enabling the development of effective drugs for the prevention and/or treatment of Lyme disease. PMID:24822172

  13. The voltage-sensitive dye di-4-ANEPPS slows conduction velocity in isolated guinea pig hearts

    PubMed Central

    Larsen, Anders Peter; Sciuto, Katie J.; Moreno, Alonso P.; Poelzing, Steven

    2014-01-01

    BACKGROUND Voltage-sensitive dyes are important tools for mapping electrical activity in the heart. However, little is known about the effects of voltage-sensitive dyes on cardiac electrophysiology. OBJECTIVE To test the hypothesis that the voltage-sensitive dye di-4-ANEPPS modulates cardiac impulse propagation. METHODS Electrical and optical mapping experiments were performed in isolated Langendorff perfused guinea pig hearts. The effect of di-4-ANEPPS on conduction velocity and anisotropy of propagation was quantified. HeLa cells expressing connexin 43 were used to evaluate the effect of di-4-ANEPPS on gap junctional conductance. RESULTS In electrical mapping experiments, di-4-ANEPPS (7.5 μM) was found to decrease both longitudinal and transverse conduction velocities significantly compared with control. No change in the anisotropy of propagation was observed. Similar results were obtained in optical mapping experiments. In these experiments, the effect of di-4-ANEPPS was dose dependent. di-4-ANEPPS had no detectable effect on connexin 43–mediated gap junctional conductance in transfected HeLa cells. CONCLUSION Our results demonstrate that the voltage-sensitive dye di-4-ANEPPS directly and dose-dependently modulates cardiac impulse propagation. The effect is not likely mediated by connexin 43 inhibition. Our results highlight an important caveat that should be taken into account when interpreting data obtained using di-4-ANEPPS in cardiac preparations. PMID:22537886

  14. Palladium-catalyzed arylation of (di)azinyl aldoxime ethers by aryl iodides: stereoselective synthesis of unsymmetrical (E)-(di)azinylaryl ketoxime ethers.

    PubMed

    Gou, Quan; Deng, Bin; Qin, Jun

    2015-09-01

    The first example of direct arylation of (di)azinyl aldoxime ethers by aryl iodides is reported. The reaction produces, in a single step, a variety of geometrically pure unsymmetrical (E)-(di)azinylaryl ketoxime ethers, a class of nitrogenated motifs that have found wide applications in medicinal and organic chemistry but are difficult to access using conventional procedure. The utility of the method is further illustrated in a formal synthesis of the Merck melanin-concentrating hormone 1 receptor antagonist. PMID:26208223

  15. Too much of a good thing: regulated depletion of c-di-AMP in the bacterial cytoplasm.

    PubMed

    Huynh, TuAnh Ngoc; Woodward, Joshua J

    2016-04-01

    Bacteria that synthesize c-di-AMP also encode several mechanisms for controlling c-di-AMP levels within the cytoplasm. One major class of phosphodiesterases comprises GdpP and DhhP homologs, which degrade c-di-AMP into the linear molecule 5'-pApA or AMP by the DHH-DHHA1 domain. The other major class comprises PgpH homologs, which degrade c-di-AMP by the HD domain. Both GdpP and PgpH harbor sensory domains, likely to regulate c-di-AMP hydrolysis activity in response to signal input. As another possible mechanism for controlling cytoplasmic c-di-AMP levels, bacteria also secrete c-di-AMP via multidrug resistance transporters, as demonstrated for Listeria monocytogenes. Mutants that accumulate high c-di-AMP levels, by deletion of phosphodiesterases or multidrug resistance transporters, exhibit aberrant physiology, growth defects, and attenuated virulence in infection. PMID:26773214

  16. [La sindrome metabolica in un campione italiano di pazienti psichiatrici: uno studio retrospettivo su soggetti trattati con antipsicotici].

    PubMed

    Santini, Ilaria; Stratta, Paolo; D'Onofrio, Simona; De Lauretis, Ida; Santarelli, Valeria; Pacitti, Francesca; Rossi, Alessandro

    2016-01-01

    RIASSUNTO. Introduzione. La sindrome metabolica (SM) è un tema di interesse centrale nell'ambito della salute mentale, visto l'aumentato rischio di comorbilità medica e di mortalità tra gli individui con patologia psichiatrica grave rispetto alla popolazione generale. Il presente studio trasversale è volto a stimare la prevalenza della SM in un campione di pazienti psichiatrici di nazionalità italiana, trattati con diversi tipi di antipsicotici. Metodi. I dati sono stati raccolti da cartelle cliniche di pazienti con psicosi affettive e non affettive, ricoverati consecutivamente presso il reparto psichiatrico dell'ospedale dell'Aquila, dal gennaio 2012 al luglio 2014. Il campione si riferisce a individui di entrambi i sessi e di età superiore ai 18 anni, in trattamento con uno o più antipsicotici. La diagnosi di SM è stata formulata in accordo ai criteri diagnostici del Treatment Panel (NCEP-ATP III). Risultati. Sono stati valutati 389 soggetti. Il 27,5% del campione risulta affetto da SM, prevalenza molto simile a quella riportata per la popolazione generale italiana che si attesta intorno al 26%. Allo stesso modo, i valori di BMI risultano essere molto simili tra queste due popolazioni, mentre, nel campione clinico, si registra un tasso di obesità più elevato. I tassi di prevalenza di SM nei sottocampioni di pazienti affetti da schizofrenia, disturbi bipolari e disturbi depressivi sono stati rispettivamente 30,6%, 36,4% e 36,8%. Fra i tre gruppi diagnostici non si evidenziano differenze significative nella prevalenza della SM, il diabete o la dislipidemia. Non emergono differenze significative nella prevalenza della SM né in relazione alla politerapia antipsicotica, né in relazione all'utilizzo di antipsicotici tipici o atipici. Nell'ambito del campione clinico, si registrano, tuttavia, tassi di obesità più elevata per i soggetti di sesso femminile, con una distribuzione del tipo "Tutto o nulla" (cioè maggiori tassi di obesità e normopeso, minori tassi di sovrappeso) rispetto alla popolazione generale. Conclusioni. I risultati del nostro studio potrebbero essere spiegati con l'interazione di più fattori quali il trattamento farmacologico, i lifestyle malattia correlati, il sesso e altre variabili (per es., predisposizione genetica) che concorrono a determinare problematiche metaboliche di diversa natura. PMID:27030348

  17. Secreted Cyclic Di-GMP Induces Stalk Cell Differentiation in the Eukaryote Dictyostelium discoideum

    PubMed Central

    Chen, Zhi-hui

    2015-01-01

    Cyclic di-GMP (c-di-GMP) is currently recognized as the most widely used intracellular signal molecule in prokaryotes, but roles in eukaryotes were only recently discovered. In the social amoeba Dictyostelium discoideum, c-di-GMP, produced by a prokaryote-type diguanylate cyclase, induces the differentiation of stalk cells, thereby enabling the formation of spore-bearing fruiting bodies. In this review, we summarize the currently known mechanisms that control the major life cycle transitions of Dictyostelium and focus particularly on the role of c-di-GMP in stalk formation. Stalk cell differentiation has characteristics of autophagic cell death, a process that also occurs in higher eukaryotes. We discuss the respective roles of c-di-GMP and of another signal molecule, differentiation-inducing factor 1, in autophagic cell death in vitro and in stalk formation in vivo. PMID:26013485

  18. Secreted Cyclic Di-GMP Induces Stalk Cell Differentiation in the Eukaryote Dictyostelium discoideum.

    PubMed

    Chen, Zhi-hui; Schaap, Pauline

    2016-01-01

    Cyclic di-GMP (c-di-GMP) is currently recognized as the most widely used intracellular signal molecule in prokaryotes, but roles in eukaryotes were only recently discovered. In the social amoeba Dictyostelium discoideum, c-di-GMP, produced by a prokaryote-type diguanylate cyclase, induces the differentiation of stalk cells, thereby enabling the formation of spore-bearing fruiting bodies. In this review, we summarize the currently known mechanisms that control the major life cycle transitions of Dictyostelium and focus particularly on the role of c-di-GMP in stalk formation. Stalk cell differentiation has characteristics of autophagic cell death, a process that also occurs in higher eukaryotes. We discuss the respective roles of c-di-GMP and of another signal molecule, differentiation-inducing factor 1, in autophagic cell death in vitro and in stalk formation in vivo. PMID:26013485

  19. Antiandrogenic effects in male rats perinatally exposed to a mixture of di(2-ethylhexyl) phthalate and di(2-ethylhexyl) adipate.

    PubMed

    Jarfelt, Kirsten; Dalgaard, Majken; Hass, Ulla; Borch, Julie; Jacobsen, Helene; Ladefoged, Ole

    2005-01-01

    Di(2-ethylhexyl) phthalate (DEHP) is a well-known testicular toxicant inducing adverse effects in androgen responsive tissues. Therefore, di(2-ethylhexyl) adipate (DEHA) is currently being evaluated as a potential substitute for DEHP. Similarities in structure and metabolism of DEHP and DEHA have led to the hypothesis that DEHA can modulate the effects of DEHP. Wistar rats were gavaged with either vehicle, DEHP (300 or 750mg/kg bw/day) or DEHP (750mg/kg bw/day) in combination with DEHA (400mg/kg bw/day) from gestation day (GD) 7 to postnatal day (PND) 17. Decreased anogenital distance (AGD) and retention of nipples in male offspring were found in all three exposed groups. Dosed males exhibited decreased weights of ventral prostate and m. levator ani/bulbocavernosus. Histopathological investigations revealed alterations in testis morphology in both juvenile and adult animals. The litter size was decreased and postnatal mortality was increased in the combination group only, which is likely a combined effect of DEHP and DEHA. However, no combination effect was seen with respect to antiandrogenic effects, as males receiving DEHP in combination with DEHA did not exhibit more pronounced effects in the reproductive system than males receiving DEHP alone. PMID:15749265

  20. Chronic toxicity of di-n-butyl and di-n-octyl phthalate to Daphnia magna and the fathead minnow

    SciTech Connect

    McCarthy, J.F.; Whitmore, D.K.

    1985-01-01

    The toxicities of di-n-butyl phthalate (DBP) and di-n-octyl phthalate (DOP) were assessed by measuring the effect of exposure to these compounds on the fecundity of Daphnia magna and on the hatching and survival of the early life stages of the fathead minnow Pimephales promelas. For D. magna, exposure to 1.8 mg/L DBP or 1.0 mg/L DOP caused a significant reduction in reproduction. Doses of 0.56 mg/L DBP or 0.32 mg/L DOP had no significant effect in decreasing reproduction. Survival of fathead minnow embryos was decreased by exposure to 1.8 mg/L DBP; none of the embryos exposed to this dose hatched successfully. Hatching and larval survival were affected by exposure to 1.0 mg/L DBP, but not to 0.56 mg/L. Exposure to DOP did not affect survival of either early embryos or larvae of the fathead minnow at doses up to 10 mg/L (the highest dose tested). Hatching of the embryos was significantly decreased at 10 mg/L, but not at 3.2 mg/L DOP. 26 references, 4 figures, 11 tables.

  1. Novel Cyclic di-GMP Effectors of the YajQ Protein Family Control Bacterial Virulence

    PubMed Central

    An, Shi-qi; Caly, Delphine L.; McCarthy, Yvonne; Murdoch, Sarah L.; Ward, Joseph; Febrer, Melanie; Dow, J. Maxwell; Ryan, Robert P.

    2014-01-01

    Bis-(3′,5′) cyclic di-guanylate (cyclic di-GMP) is a key bacterial second messenger that is implicated in the regulation of many critical processes that include motility, biofilm formation and virulence. Cyclic di-GMP influences diverse functions through interaction with a range of effectors. Our knowledge of these effectors and their different regulatory actions is far from complete, however. Here we have used an affinity pull-down assay using cyclic di-GMP-coupled magnetic beads to identify cyclic di-GMP binding proteins in the plant pathogen Xanthomonas campestris pv. campestris (Xcc). This analysis identified XC_3703, a protein of the YajQ family, as a potential cyclic di-GMP receptor. Isothermal titration calorimetry showed that the purified XC_3703 protein bound cyclic di-GMP with a high affinity (Kd∼2 µM). Mutation of XC_3703 led to reduced virulence of Xcc to plants and alteration in biofilm formation. Yeast two-hybrid and far-western analyses showed that XC_3703 was able to interact with XC_2801, a transcription factor of the LysR family. Mutation of XC_2801 and XC_3703 had partially overlapping effects on the transcriptome of Xcc, and both affected virulence. Electromobility shift assays showed that XC_3703 positively affected the binding of XC_2801 to the promoters of target virulence genes, an effect that was reversed by cyclic di-GMP. Genetic and functional analysis of YajQ family members from the human pathogens Pseudomonas aeruginosa and Stenotrophomonas maltophilia showed that they also specifically bound cyclic di-GMP and contributed to virulence in model systems. The findings thus identify a new class of cyclic di-GMP effector that regulates bacterial virulence. PMID:25329577

  2. Cyclic Di-GMP Modulates the Disease Progression of Erwinia amylovora

    PubMed Central

    Edmunds, Adam C.; Castiblanco, Luisa F.; Sundin, George W.

    2013-01-01

    The second messenger cyclic di-GMP (c-di-GMP) is a nearly ubiquitous intracellular signal molecule known to regulate various cellular processes, including biofilm formation, motility, and virulence. The intracellular concentration of c-di-GMP is inversely governed by diguanylate cyclase (DGC) enzymes and phosphodiesterase (PDE) enzymes, which synthesize and degrade c-di-GMP, respectively. The role of c-di-GMP in the plant pathogen and causal agent of fire blight disease Erwinia amylovora has not been studied previously. Here we demonstrate that three of the five predicted DGC genes in E. amylovora (edc genes, for Erwinia diguanylate cyclase), edcA, edcC, and edcE, are active diguanylate cyclases. We show that c-di-GMP positively regulates the secretion of the main exopolysaccharide in E. amylovora, amylovoran, leading to increased biofilm formation, and negatively regulates flagellar swimming motility. Although amylovoran secretion and biofilm formation are important for the colonization of plant xylem tissues and the development of systemic infections, deletion of the two biofilm-promoting DGCs increased tissue necrosis in an immature-pear infection assay and an apple shoot infection model, suggesting that c-di-GMP negatively regulates virulence. In addition, c-di-GMP inhibited the expression of hrpA, a gene encoding the major structural component of the type III secretion pilus. Our results are the first to describe a role for c-di-GMP in E. amylovora and suggest that downregulation of motility and type III secretion by c-di-GMP during infection plays a key role in the coordination of pathogenesis. PMID:23475975

  3. Cyclic di-GMP: the First 25 Years of a Universal Bacterial Second Messenger

    PubMed Central

    Galperin, Michael Y.; Gomelsky, Mark

    2013-01-01

    SUMMARY Twenty-five years have passed since the discovery of cyclic dimeric (3′→5′) GMP (cyclic di-GMP or c-di-GMP). From the relative obscurity of an allosteric activator of a bacterial cellulose synthase, c-di-GMP has emerged as one of the most common and important bacterial second messengers. Cyclic di-GMP has been shown to regulate biofilm formation, motility, virulence, the cell cycle, differentiation, and other processes. Most c-di-GMP-dependent signaling pathways control the ability of bacteria to interact with abiotic surfaces or with other bacterial and eukaryotic cells. Cyclic di-GMP plays key roles in lifestyle changes of many bacteria, including transition from the motile to the sessile state, which aids in the establishment of multicellular biofilm communities, and from the virulent state in acute infections to the less virulent but more resilient state characteristic of chronic infectious diseases. From a practical standpoint, modulating c-di-GMP signaling pathways in bacteria could represent a new way of controlling formation and dispersal of biofilms in medical and industrial settings. Cyclic di-GMP participates in interkingdom signaling. It is recognized by mammalian immune systems as a uniquely bacterial molecule and therefore is considered a promising vaccine adjuvant. The purpose of this review is not to overview the whole body of data in the burgeoning field of c-di-GMP-dependent signaling. Instead, we provide a historic perspective on the development of the field, emphasize common trends, and illustrate them with the best available examples. We also identify unresolved questions and highlight new directions in c-di-GMP research that will give us a deeper understanding of this truly universal bacterial second messenger. PMID:23471616

  4. Near-infrared Light Responsive Synthetic c-di-GMP Module for Optogenetic Applications

    PubMed Central

    2015-01-01

    Enormous potential of cell-based therapeutics is hindered by the lack of effective means to control genetically engineered cells in mammalian tissues. Here, we describe a synthetic module for remote photocontrol of engineered cells that can be adapted for such applications. The module involves photoactivated synthesis of cyclic dimeric GMP (c-di-GMP), a stable small molecule that is not produced by higher eukaryotes and therefore is suitable for orthogonal regulation. The key component of the photocontrol module is an engineered bacteriophytochrome diguanylate cyclase, which synthesizes c-di-GMP from GTP in a light-dependent manner. Bacteriophytochromes are particularly attractive photoreceptors because they respond to light in the near-infrared window of the spectrum, where absorption by mammalian tissues is minimal, and also because their chromophore, biliverdin IXα, is naturally available in mammalian cells. The second component of the photocontrol module, a c-di-GMP phosphodiesterase, maintains near-zero background levels of c-di-GMP in the absence of light, which enhances the photodynamic range of c-di-GMP concentrations. In the E. coli model used in this study, the intracellular c-di-GMP levels could be upregulated by light by >50-fold. Various c-di-GMP-responsive proteins and riboswitches identified in bacteria can be linked downstream of the c-di-GMP-mediated photocontrol module for orthogonal regulation of biological activities in mammals as well as in other organisms lacking c-di-GMP signaling. Here, we linked the photocontrol module to a gene expression output via a c-di-GMP-responsive transcription factor and achieved a 40-fold photoactivation of gene expression. PMID:24926804

  5. Cyclic Di-GMP modulates the disease progression of Erwinia amylovora.

    PubMed

    Edmunds, Adam C; Castiblanco, Luisa F; Sundin, George W; Waters, Christopher M

    2013-05-01

    The second messenger cyclic di-GMP (c-di-GMP) is a nearly ubiquitous intracellular signal molecule known to regulate various cellular processes, including biofilm formation, motility, and virulence. The intracellular concentration of c-di-GMP is inversely governed by diguanylate cyclase (DGC) enzymes and phosphodiesterase (PDE) enzymes, which synthesize and degrade c-di-GMP, respectively. The role of c-di-GMP in the plant pathogen and causal agent of fire blight disease Erwinia amylovora has not been studied previously. Here we demonstrate that three of the five predicted DGC genes in E. amylovora (edc genes, for Erwinia diguanylate cyclase), edcA, edcC, and edcE, are active diguanylate cyclases. We show that c-di-GMP positively regulates the secretion of the main exopolysaccharide in E. amylovora, amylovoran, leading to increased biofilm formation, and negatively regulates flagellar swimming motility. Although amylovoran secretion and biofilm formation are important for the colonization of plant xylem tissues and the development of systemic infections, deletion of the two biofilm-promoting DGCs increased tissue necrosis in an immature-pear infection assay and an apple shoot infection model, suggesting that c-di-GMP negatively regulates virulence. In addition, c-di-GMP inhibited the expression of hrpA, a gene encoding the major structural component of the type III secretion pilus. Our results are the first to describe a role for c-di-GMP in E. amylovora and suggest that downregulation of motility and type III secretion by c-di-GMP during infection plays a key role in the coordination of pathogenesis. PMID:23475975

  6. Near-infrared light responsive synthetic c-di-GMP module for optogenetic applications.

    PubMed

    Ryu, Min-Hyung; Gomelsky, Mark

    2014-11-21

    Enormous potential of cell-based therapeutics is hindered by the lack of effective means to control genetically engineered cells in mammalian tissues. Here, we describe a synthetic module for remote photocontrol of engineered cells that can be adapted for such applications. The module involves photoactivated synthesis of cyclic dimeric GMP (c-di-GMP), a stable small molecule that is not produced by higher eukaryotes and therefore is suitable for orthogonal regulation. The key component of the photocontrol module is an engineered bacteriophytochrome diguanylate cyclase, which synthesizes c-di-GMP from GTP in a light-dependent manner. Bacteriophytochromes are particularly attractive photoreceptors because they respond to light in the near-infrared window of the spectrum, where absorption by mammalian tissues is minimal, and also because their chromophore, biliverdin IXα, is naturally available in mammalian cells. The second component of the photocontrol module, a c-di-GMP phosphodiesterase, maintains near-zero background levels of c-di-GMP in the absence of light, which enhances the photodynamic range of c-di-GMP concentrations. In the E. coli model used in this study, the intracellular c-di-GMP levels could be upregulated by light by >50-fold. Various c-di-GMP-responsive proteins and riboswitches identified in bacteria can be linked downstream of the c-di-GMP-mediated photocontrol module for orthogonal regulation of biological activities in mammals as well as in other organisms lacking c-di-GMP signaling. Here, we linked the photocontrol module to a gene expression output via a c-di-GMP-responsive transcription factor and achieved a 40-fold photoactivation of gene expression. PMID:24926804

  7. Responses to elevated c-di-GMP levels in mutualistic and pathogenic plant-interacting bacteria.

    PubMed

    Pérez-Mendoza, Daniel; Aragón, Isabel M; Prada-Ramírez, Harold A; Romero-Jiménez, Lorena; Ramos, Cayo; Gallegos, María-Trinidad; Sanjuán, Juan

    2014-01-01

    Despite a recent burst of research, knowledge on c-di-GMP signaling pathways remains largely fragmentary and molecular mechanisms of regulation and even c-di-GMP targets are yet unknown for most bacteria. Besides genomics or bioinformatics, accompanying alternative approaches are necessary to reveal c-di-GMP regulation in bacteria with complex lifestyles. We have approached this study by artificially altering the c-di-GMP economy of diverse pathogenic and mutualistic plant-interacting bacteria and examining the effects on the interaction with their respective host plants. Phytopathogenic Pseudomonas and symbiotic Rhizobium strains with enhanced levels of intracellular c-di-GMP displayed common free-living responses: reduction of motility, increased production of extracellular polysaccharides and enhanced biofilm formation. Regarding the interaction with the host plants, P. savastanoi pv. savastanoi cells containing high c-di-GMP levels formed larger knots on olive plants which, however, displayed reduced necrosis. In contrast, development of disease symptoms in P. syringae-tomato or P. syringae-bean interactions did not seem significantly affected by high c-di-GMP. On the other hand, increasing c-di-GMP levels in symbiotic R. etli and R. leguminosarum strains favoured the early stages of the interaction since enhanced adhesion to plant roots, but decreased symbiotic efficiency as plant growth and nitrogen contents were reduced. Our results remark the importance of c-di-GMP economy for plant-interacting bacteria and show the usefulness of our approach to reveal particular stages during plant-bacteria associations which are sensitive to changes in c-di-GMP levels. PMID:24626229

  8. Responses to Elevated c-di-GMP Levels in Mutualistic and Pathogenic Plant-Interacting Bacteria

    PubMed Central

    Pérez-Mendoza, Daniel; Aragón, Isabel M.; Prada-Ramírez, Harold A.; Romero-Jiménez, Lorena; Ramos, Cayo; Gallegos, María-Trinidad; Sanjuán, Juan

    2014-01-01

    Despite a recent burst of research, knowledge on c-di-GMP signaling pathways remains largely fragmentary and molecular mechanisms of regulation and even c-di-GMP targets are yet unknown for most bacteria. Besides genomics or bioinformatics, accompanying alternative approaches are necessary to reveal c-di-GMP regulation in bacteria with complex lifestyles. We have approached this study by artificially altering the c-di-GMP economy of diverse pathogenic and mutualistic plant-interacting bacteria and examining the effects on the interaction with their respective host plants. Phytopathogenic Pseudomonas and symbiotic Rhizobium strains with enhanced levels of intracellular c-di-GMP displayed common free-living responses: reduction of motility, increased production of extracellular polysaccharides and enhanced biofilm formation. Regarding the interaction with the host plants, P. savastanoi pv. savastanoi cells containing high c-di-GMP levels formed larger knots on olive plants which, however, displayed reduced necrosis. In contrast, development of disease symptoms in P. syringae-tomato or P. syringae-bean interactions did not seem significantly affected by high c-di-GMP. On the other hand, increasing c-di-GMP levels in symbiotic R. etli and R. leguminosarum strains favoured the early stages of the interaction since enhanced adhesion to plant roots, but decreased symbiotic efficiency as plant growth and nitrogen contents were reduced. Our results remark the importance of c-di-GMP economy for plant-interacting bacteria and show the usefulness of our approach to reveal particular stages during plant-bacteria associations which are sensitive to changes in c-di-GMP levels. PMID:24626229

  9. Diffusion boriding of a press tool of DI22 steel

    SciTech Connect

    Duryagina, Z.A.; Pastukhova, L.V.; Kitsak, M.I.

    1987-11-01

    For the purpose of increasing the quality and thickness uniformity of the borided case on parts of complex configuration they used a method of boriding in a molten active low-melting transport metal making it possible to combine diffusion impregnation with subsequent heat treatment. The transport metal was lithium. The final purpose of this investigation was the development of a method of hardening coatings for press tools of DI22 (4Kh4VMFS) steel with (%) 0.37-0.44 C, 0.2-0.5 Mn, 3.2-4.0 Cr, 0.8-1.2 W, 0.6-0.9 V, 1.2-1.5 Mo, and 0.6-1.0 Si.

  10. Test and Analysis of Spliced DI-BSCCO HTS Tapes

    NASA Astrophysics Data System (ADS)

    Fetisov, S. S.; Sotnikov, D. V.; Radchenko, I. P.; Vysotsky, V. S.; Osabe, G.; Kinoshita, K.; Fujikami, J.; Kobayashi, S.; Yamazaki, K.

    For some applications, short unit lengths of HTS wires should be spliced if longer lengths are necessary and short unit lengths of HTS wires should be utilize by applying the splice technology to reduce the total wire cost in the application. The splice technology has been developed for DI-BSCCO Type HT-CA tapes by Sumitomo Electric and spliced tapes were tested in Russian Cable Institute. The test program included: measurements of splice's resistance, critical current anisotropy, thermo cycling tolerance, mechanical properties, overload tests and magnetization measurements. In the paper the results of tests are presented and discussed. The test results demonstrated that splices can be used for cable production if twisting and bending limitations are taken into account.

  11. Taming of 3,4-Di(nitramino)furazan.

    PubMed

    Tang, Yongxing; Zhang, Jiaheng; Mitchell, Lauren A; Parrish, Damon A; Shreeve, Jean'ne M

    2015-12-30

    Highly energetic 3,4-di(nitramino)furazan (1, DNAF) was synthesized and confirmed structurally by using single-crystal X-ray diffraction. Its highly sensitive nature can be attributed to the shortage of hydrogen-bonding interactions and an interactive nitro chain in the crystal structure. In order to stabilize this structure, a series of corresponding nitrogen-rich salts (3-10) has been prepared and fully characterized. Among these energetic materials, dihydrazinium 3,4-dinitraminofurazanate (5) exhibits a very promising detonation performance (νD = 9849 m s(-1); P = 40.9 GPa) and is one of the most powerful explosives to date. To ensure the practical applications of 5, rather than preparing the salts of 1 through acid-base reactions, an alternative route through the nitration of N-ethoxycarbonyl-protected 3,4-diaminofurazan and aqueous alkaline workup was developed. PMID:26669520

  12. Is an axizilla possible for di-photon resonance?

    NASA Astrophysics Data System (ADS)

    Kim, Jihn E.

    2016-04-01

    Heavy axion-like particles, called axizillas, are simple extensions of the standard model (SM). An axizilla is required not to couple to the quarks, leptons, and Brout-Englert-Higgs doublets of the SM, but couple to the gauge anomalies of the W±, Z and photon. It is possible to have its branching ratios (BRs) to two photons greater than 10 % and to two Z's less than 10 %. To have a (production cross section) ṡ (BR to di-photons) at a 10-38 cm2 level, a TeV scale heavy quark Q is required for the gluon-quark fusion process. The decay of Q to axizilla plus quark, and the subsequent decay of the axizilla to two photons can be fitted at the required level of 10-38 cm2.

  13. Aqueous infrared carboxylate absorbances: Aliphatic di-acids

    USGS Publications Warehouse

    Cabaniss, S.E.; Leenheer, J.A.; McVey, I.F.

    1998-01-01

    Aqueous attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectra of 18 aliphatic di-carboxylic acids are reported as a function of pH. The spectra show isosbestic points and intensity changes which indicate that Beer's law is obeyed, and peak frequencies lie within previously reported ranges for aqueous carboxylates and pure carboxylic acids. Intensity sharing from the symmetric carboxylate stretch is evident in many cases, so that bands which are nominally due to alkyl groups show increased intensity at higher pH. The asymmetric stretch of the HA- species is linearly related to the microscopic acidity constant of the H2A species, with ??pK 2 intervening atoms). The results suggest that aqueous ATR-FTIR may be able to estimate 'intrinsic' pKa values of carboxylic acids, in addition to providing quantitative estimates of ionization. ?? 1998 Elsevier Science B.V. All rights reserved.

  14. Sensing the messenger: The diverse ways that bacteria signal through c-di-GMP

    PubMed Central

    Krasteva, Petya Violinova; Giglio, Krista Michelle; Sondermann, Holger

    2012-01-01

    An intracellular second messenger unique to bacteria, c-di-GMP, has gained appreciation as a key player in adaptation and virulence strategies, such as biofilm formation, persistence, and cytotoxicity. Diguanylate cyclases containing GGDEF domains and phosphodiesterases containing either EAL or HD-GYP domains have been identified as the enzymes controlling intracellular c-di-GMP levels, yet little is known regarding signal transmission and the sensory targets for this signaling molecule. Although limited in number, identified c-di-GMP receptors in bacteria are characterized by prominent diversity and multilevel impact. In addition, c-di-GMP has been shown to have immunomodulatory effects in mammals and several eukaryotic c-di-GMP sensors have been proposed. The structural biology of c-di-GMP receptors is a rapidly developing field of research, which holds promise for the development of novel therapeutics against bacterial infections. In this review, we highlight recent advances in identifying bacterial and eukaryotic c-di-GMP signaling mechanisms and emphasize the need for mechanistic structure–function studies on confirmed signaling targets. PMID:22593024

  15. Identification of c-di-GMP derivatives resistant to an EAL domain phosphodiesterase.

    PubMed

    Shanahan, Carly A; Gaffney, Barbara L; Jones, Roger A; Strobel, Scott A

    2013-01-15

    The bacterial second messenger signaling molecule bis-(3'-5')-cyclic dimeric guanosine monophosphate (c-di-GMP) controls important biological processes such as biofilm formation, virulence response, and motility. This second messenger is sensed by macromolecular targets inside the cell, both protein and RNA, which induce specific phenotypic responses critical for bacterial survival. One class of enzymes responsible for regulating the intracellular concentration of c-di-GMP, and therefore the physiological behavior of the cell, consists of the EAL domain phosphodiesterases, which degrade the second messenger to its linear form, pGpG. Here, we investigate how base and backbone modifications of c-di-GMP affect the rate of cyclic dinucleotide degradation by an EAL domain protein (CC3396 from Caulobacter crescentus). The doubly substituted thiophosphate analogue is highly resistant to hydrolysis by this metabolizing enzyme but can still bind c-di-GMP riboswitch targets. We used these findings to develop a novel ribosyl phosphate-modified derivative of c-di-GMP containing 2'-deoxy and methylphosphonate substitutions that is charge neutral and demonstrate that this analogue is also resistant to EAL domain-catalyzed degradation. This suggests a general strategy for designing c-di-GMP derivatives with increased enzymatic stability that also possess desirable properties for development as chemical probes of c-di-GMP signaling. PMID:23256840

  16. Functional Characterization of Core Components of the Bacillus subtilis Cyclic-Di-GMP Signaling Pathway

    PubMed Central

    Gao, Xiaohui; Mukherjee, Sampriti; Matthews, Paige M.; Hammad, Loubna A.; Kearns, Daniel B.

    2013-01-01

    Bis-(3′-5′)-cyclic dimeric GMP (c-di-GMP) is an intracellular second messenger that regulates adaptation processes, including biofilm formation, motility, and virulence in Gram-negative bacteria. In this study, we have characterized the core components of a c-di-GMP signaling pathway in the model Gram-positive bacterium Bacillus subtilis. Specifically, we have directly identified and characterized three active diguanylate cyclases, DgcP, DgcK, and DgcW (formerly YtrP, YhcK, and YkoW, respectively), one active c-di-GMP phosphodiesterase, PdeH (formerly YuxH), and a cyclic-diguanylate (c-di-GMP) receptor, DgrA (formerly YpfA). Furthermore, elevation of c-di-GMP levels in B. subtilis led to inhibition of swarming motility, whereas biofilm formation was unaffected. Our work establishes paradigms for Gram-positive c-di-GMP signaling, and we have shown that the concise signaling system identified in B. subtilis serves as a powerful heterologous host for the study of c-di-GMP enzymes from bacteria predicted to possess larger, more-complex signaling systems. PMID:23893111

  17. MOVPE growth of (100) CdZnTe layers using DiPZn

    NASA Astrophysics Data System (ADS)

    Yasuda, K.; Minamide, M.; Kawamoto, K.; Maejima, T.

    1996-02-01

    Growth characteristics of (100) Cd 1 - xZn xTe (CZT) have been studied in MOVPE. CZT layers were grown on (100) GaAs substrates using diisopropylzinc (DiPZn), dimethylcadmium (DMCd) and diethyltelluride (DETe) as precursors. Growths were carried out in the temperature range from 375 to 450°C. Since DiPZn has a lower vapor pressure than DMCd, CZT layers with a Zn composition below 0.06 were grown under good compositional controllability. Layers with uniform Zn composition and thickness over the growth surface were grown at this low Zn composition region. The crystallinity of the grown layers was also evaluated. The results showed that DiPZn is suitable for growth of CZT layers, wich lattice-match with the HgCdTe layers. Enhancement of the CZT growth rate was observed upon introduction of a small amount of DiPZn under fixed flows of DMCd and DETe. The Zn composition increases abruptly upon further increase of the DiPZn flow, where the growth rate decreases. Growth characteristics were also studied by changing the DiPZn ratio while keeping the sum of the DiPZn and DMCd flow rates constant. The growth mechanisms under the above growth conditions are also discussed.

  18. The Mucosal Adjuvant Cyclic di-AMP Exerts Immune Stimulatory Effects on Dendritic Cells and Macrophages

    PubMed Central

    Libanova, Rimma; Lienenklaus, Stefan; Weiss, Siegfried; Guzmán, Carlos A.

    2014-01-01

    The cyclic di-nucleotide bis-(3′,5′)-cyclic dimeric adenosine monophosphate (c-di-AMP) is a candidate mucosal adjuvant with proven efficacy in preclinical models. It was shown to promote specific humoral and cellular immune responses following mucosal administration. To date, there is only fragmentary knowledge on the cellular and molecular mode of action of c-di-AMP. Here, we report on the identification of dendritic cells and macrophages as target cells of c-di-AMP. We show that c-di-AMP induces the cell surface up-regulation of T cell co-stimulatory molecules as well as the production of interferon-β. Those responses were characterized by in vitro experiments with murine and human immune cells and in vivo studies in mice. Analyses of dendritic cell subsets revealed conventional dendritic cells as principal responders to stimulation by c-di-AMP. We discuss the impact of the reported antigen presenting cell activation on the previously observed adjuvant effects of c-di-AMP in mouse immunization studies. PMID:24755640

  19. Cyclic di-GMP-dependent Signaling Pathways in the Pathogenic Firmicute Listeria monocytogenes

    PubMed Central

    Chen, Li-Hong; Köseoğlu, Volkan K.; Güvener, Zehra T.; Myers-Morales, Tanya; Reed, Joseph M.; D'Orazio, Sarah E. F.; Miller, Kurt W.; Gomelsky, Mark

    2014-01-01

    We characterized key components and major targets of the c-di-GMP signaling pathways in the foodborne pathogen Listeria monocytogenes, identified a new c-di-GMP-inducible exopolysaccharide responsible for motility inhibition, cell aggregation, and enhanced tolerance to disinfectants and desiccation, and provided first insights into the role of c-di-GMP signaling in listerial virulence. Genome-wide genetic and biochemical analyses of c-di-GMP signaling pathways revealed that L. monocytogenes has three GGDEF domain proteins, DgcA (Lmo1911), DgcB (Lmo1912) and DgcC (Lmo2174), that possess diguanylate cyclase activity, and three EAL domain proteins, PdeB (Lmo0131), PdeC (Lmo1914) and PdeD (Lmo0111), that possess c-di-GMP phosphodiesterase activity. Deletion of all phosphodiesterase genes (ΔpdeB/C/D) or expression of a heterologous diguanylate cyclase stimulated production of a previously unknown exopolysaccharide. The synthesis of this exopolysaccharide was attributed to the pssA-E (lmo0527-0531) gene cluster. The last gene of the cluster encodes the fourth listerial GGDEF domain protein, PssE, that functions as an I-site c-di-GMP receptor essential for exopolysaccharide synthesis. The c-di-GMP-inducible exopolysaccharide causes cell aggregation in minimal medium and impairs bacterial migration in semi-solid agar, however, it does not promote biofilm formation on abiotic surfaces. The exopolysaccharide also greatly enhances bacterial tolerance to commonly used disinfectants as well as desiccation, which may contribute to survival of L. monocytogenes on contaminated food products and in food-processing facilities. The exopolysaccharide and another, as yet unknown c-di-GMP-dependent target, drastically decrease listerial invasiveness in enterocytes in vitro, and lower pathogen load in the liver and gallbladder of mice infected via an oral route, which suggests that elevated c-di-GMP levels play an overall negative role in listerial virulence. PMID:25101646

  20. Association of exposure to di-2-ethylhexylphthalate replacements with increased blood pressure in children and adolescents.

    PubMed

    Trasande, Leonardo; Attina, Teresa M

    2015-08-01

    Phthalates are environmental chemicals widely used in consumer and personal care products. In this study, we examined associations of urinary phthalates with blood pressure, triglycerides, and lipoproteins in children and adolescents, performing a cross-sectional analysis of a subsample of US children 6 to 19 years of age who participated in the National Health and Nutrition Examination Survey between the years 2009 and 2012. We quantified exposure to common environmental phthalates, with a focus on the dietary contaminant di-2-ethylhexylphthalate and 2 increasingly used replacements, di-isononyl phthalate and di-isodecyl phthalate, based on micromolar concentration of urinary metabolites. We assessed descriptive, univariate, and multivariable associations with blood pressure and lipids. Controlling for an array of sociodemographic and behavioral factors, as well as diet and body mass, metabolites of di-2-ethylhexylphthalate, di-isononyl phthalate, and di-isodecyl phthalate were associated with higher age-, sex- and height-standardized blood pressure. For each log unit increase in di-isodecyl phthalate metabolites, a 0.105 standard deviation unit increase in systolic blood pressure z score was identified (P=0.004); for di-isononyl phthalate metabolites, a 0.113 standard deviation unit increment was identified (P=0.008). For di-2-ethylhexylphthalate metabolites, a 0.103 standard deviation unit increment (P=0.013) was detected. Metabolites of low molecular weight phthalates commonly found in cosmetics and personal care products showed an association with blood pressure (≥90th percentile) in univariate analysis, but this was no longer significant in our full multivariable model, suggesting specificity. Phthalate metabolites were not associated with triglycerides or high-density lipoproteins. Further, longitudinal studies are needed to confirm these associations and to assess opportunities for intervention. PMID:26156503

  1. Exposure to di-2-ethylhexyl phthalate, di-n-butyl phthalate and bisphenol A through infant formulas.

    PubMed

    Cirillo, Teresa; Latini, Giuseppe; Castaldi, Maria Antonietta; Dipaola, Lucia; Fasano, Evelina; Esposito, Francesco; Scognamiglio, Gelsomina; Francesco, Fabio Di; Cobellis, Luigi

    2015-04-01

    Phthalates and bisphenol A (BPA) are ubiquitous contaminants identified as endocrine disruptors. Phthalates are worldwide used as plasticizers, in particular to improve the mechanical properties of polymers such as polyvinyl chloride. Because they are not chemically bound to the polymer, they tend to leach out with time and use. Di-2-ethylhexyl phthalate (DEHP) and di-n-butyl phthalate (DnBP) are the two most common phthalates. BPA is an estrogenic compound used to manufacture polycarbonate containers for food and drink, including baby bottles. It can migrate from container into foods, especially at elevated temperatures. Diet is a predominant source of exposure for phthalates and BPA, especially for infants. The aim of this study was to test the presence of DEHP, DnBP, and BPA in infant formulas. DEHP, DnBP, and BPA concentrations were measured in 22 liquid and 28 powder milks by gas chromatography with flame ionization detection and high performance liquid chromatography with fluorimetric detection, respectively. DEHP concentrations in our samples were between 0.005 and 5.088 μg/g (median 0.906 μg/g), DnBP concentrations were between 0.008 and 1.297 μg/g (median 0.053 μg/g), and BPA concentrations were between 0.003 and 0.375 μg/g (median 0.015 μg/g). Concentrations of the investigated contaminants in liquid and powder milks were not significantly different, even though samples were packed in different types of containers. These data point out potential hazards for infants fed with baby formulas. Contamination seems more related to the production of formulas than to a release from containers. PMID:25730646

  2. Cyclic Di-GMP Regulates Type IV Pilus-Dependent Motility in Myxococcus xanthus

    PubMed Central

    Skotnicka, Dorota; Petters, Tobias; Heering, Jan; Hoppert, Michael; Kaever, Volkhard

    2015-01-01

    ABSTRACT The nucleotide-based second messenger bis-(3′-5′)-cyclic dimeric GMP (c-di-GMP) is involved in regulating a plethora of processes in bacteria that are typically associated with lifestyle changes. Myxococcus xanthus undergoes major lifestyle changes in response to nutrient availability, with the formation of spreading colonies in the presence of nutrients and spore-filled fruiting bodies in the absence of nutrients. Here, we investigated the function of c-di-GMP in M. xanthus and show that this bacterium synthesizes c-di-GMP during growth. Manipulation of the c-di-GMP level by expression of either an active, heterologous diguanylate cyclase or an active, heterologous phosphodiesterase correlated with defects in type IV pilus (T4P)-dependent motility, whereas gliding motility was unaffected. An increased level of c-di-GMP correlated with reduced transcription of the pilA gene (which encodes the major pilin of T4P), reduced the assembly of T4P, and altered cell agglutination, whereas a decreased c-di-GMP level correlated with altered cell agglutination. The systematic inactivation of the 24 genes in M. xanthus encoding proteins containing GGDEF, EAL, or HD-GYP domains, which are associated with c-di-GMP synthesis, degradation, or binding, identified three genes encoding proteins important for T4P-dependent motility, whereas all mutants had normal gliding motility. Purified DmxA had diguanylate cyclase activity, whereas the hybrid histidine protein kinases TmoK and SgmT, each of which contains a GGDEF domain, did not have diguanylate cyclase activity. These results demonstrate that c-di-GMP is important for T4P-dependent motility in M. xanthus. IMPORTANCE We provide the first direct evidence that M. xanthus synthesizes c-di-GMP and demonstrate that c-di-GMP is important for T4P-dependent motility, whereas we did not obtain evidence that c-di-GMP regulates gliding motility. The data presented uncovered a novel mechanism for regulation of T4P-dependent motility, in which increased levels of c-di-GMP inhibit transcription of the pilA gene (which encodes the major pilin of T4P), ultimately resulting in the reduced assembly of T4P. Moreover, we identified an enzymatically active diguanylate cyclase that is important for T4P-dependent motility. PMID:26124238

  3. 5-Bromo-4-(3,5-di-bromo-2-hy-droxy-phen-yl)-2-(piperidin-1-yl)-1,3-di-thiol-2-ylium bromide.

    PubMed

    Chirita, Paul; Hrib, Cristian G; Birsa, Lucian M

    2013-01-01

    In the title salt, C14H13Br3NOS2 (+)·Br(-), synthesized by bromination of mesoionic 2-[2-(piperidin-1-yl)-1,3-di-thiol-2-ylium-4-yl]phenolate in glacial acetic acid, the dihedral angle between the 1,3-di-thiol-ium ring and the phenolic substituent ring is 45.9 (3)° due to the steric influence of the ortho-Br group on the 1,3-di-thiol-ium ring. The piperidine ring adopts a chair conformation. In the crystal, the cation and anion are linked by an O-H⋯Br hydrogen bond. PMID:24046659

  4. D.O.P. and D.I. secured room, looking southeast towards the map ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    D.O.P. and D.I. secured room, looking southeast towards the map rack sliding panels and the east mural - March Air Force Base, Strategic Air Command, Combat Operations Center, 5220 Riverside Drive, Moreno Valley, Riverside County, CA

  5. Combination of diOlistic labeling with retrograde tract tracing and immunohistochemistry.

    PubMed

    Neely, M Diana; Stanwood, Gregg D; Deutch, Ariel Y

    2009-11-15

    Neuronal staining techniques have played a crucial role in the analysis of neuronal function. Several different staining techniques have been developed to allow morphological analyses of neurons. DiOlistic labeling, in which beads are coated with a lipophilic dye and then ballistically ejected onto brain tissue, has recently been introduced as a useful and simple means to label neurons and glia in their entirety. Although diOlistic labeling provides detailed information on the morphology of neurons, combining this approach with other staining methods is a significant advance. We have developed protocols that result in high quality diOlistically- and retrogradely-labeled or diOlistically-immunohistochemically labeled neurons. These dual-label methods require modification of fixation parameters and the restricted use of detergents for tissue permeabilization, and are readily applicable to a wide range of tracers and antibodies. PMID:19712695

  6. DEVELOPMENTAL TOXICITY OF DI- AND TETRACHLOROETHANE AND DICHLOROPROPANE IN EMBRYO CULTURE

    EPA Science Inventory

    DEVELOPMENTAL TOXICITY OF DI- AND TETRACHLOROETHANE AND DICHLOROPROPANE IN EMBRYO CULTURE. JE Andrews, H Nichols, and ES Hunter. Reproductive Toxicology Division, NHEERL, USEPA, RTP, NC.

    Disinfection of drinking water with chlorine results in numerous chlorinated byprodu...

  7. The expanding roles of c-di-GMP in the biosynthesis of exopolysaccharides and secondary metabolites.

    PubMed

    Liang, Zhao-Xun

    2015-05-01

    The cyclic dinucleotide c-di-GMP has emerged in the last decade as a prevalent intracellular messenger that orchestrates the transition between the motile and sessile lifestyles of many bacterial species. The motile-to-sessile transition is often associated with the formation of extracellular matrix-encased biofilm, an organized community of bacterial cells that often contributes to antibiotic resistance and host-pathogen interaction. It is increasingly clear that c-di-GMP controls motility, biofilm formation and bacterial pathogenicity partially through regulating the production of exopolysaccharides (EPS) and small-molecule secondary metabolites. This review summarizes our current understanding of the regulation of EPS biosynthesis by c-di-GMP in a diversity of bacterial species and highlights the emerging role of c-di-GMP in the biosynthesis of small-molecule secondary metabolites. PMID:25666534

  8. The oxidation of 2,6-di-tert-butyl-4-methylphenol

    USGS Publications Warehouse

    Yohe, G.R.; Dunbar, J.E.; Pedrotti, R.L.; Scheidt, F.M.; Lee, F.G.H.; Smith, E.C.

    1956-01-01

    The products formed in the oxidation of 2,6-di-tert-butyl-4-methylphenol with oxygen and sodium hydroxide at about 100?? are 3,5-di-tert-butyl-4-hydroxybenzaldehyde, trimethylacetic acid, an acidic compound C14H22O3, and probably 2,6-di-tert-butylbenzoquinone (which was actually isolated in the similar oxidation of the above-named benzaldehyde), in addition to compounds previously reported. Some of the properties of C14H22O3 are given, and the oxidation of it to 2,3-di-tert-butylsuccinic anhydride is described, but assignment of structure is reserved pending the completion of more experimental work.

  9. DECHLORINATION ACTIVITY (CROSS-ACCLIMATION) OF FRESHWATER SEDIMENTS ADAPTED TO MONO- AND DI-CHLOROPHENOLS

    EPA Science Inventory

    The reductive dechlorination of chlorophenols (CPs) in sediment slurries (10% solids) adapted to dechlorinate mono- and di-CPs (DCP) was investigated to define the regiospecificity of the dechlorination reaction. nadapted sediment slurries amended with various ortho-substituted C...

  10. BrlR from Pseudomonas aeruginosa is a c-di-GMP-responsive transcription factor

    PubMed Central

    Chambers, Jacob R.; Liao, Julie; Schurr, Michael J.; Sauer, Karin

    2014-01-01

    The transcriptional regulator BrlR is a member of the MerR family of multidrug transport activators that contributes to the high-level drug tolerance of Pseudomonas aeruginosa biofilms. While MerR regulators are known to activate both the expression of multidrug efflux pump genes and their own transcription upon inducer-binding, little is known about BrlR activation. We demonstrate using promoter reporter strains, in vivo and in vitro DNA-binding assays combined with 5’RACE, that BrlR binds to its own promoter, likely via a MerR-like palindromic sequence. Unlike known MerR multidrug transport activators, BrlR and brlR expression are not activated by multidrug transporter substrates. Instead, BrlR-DNA binding was enhanced by the secondary messenger c-di-GMP. In addition to enhanced BrlR-DNA binding, c-di-GMP levels contributed to PbrlR promoter activity in initial attached cells with elevated c-di-GMP levels correlating with increased expression of brlR. While not harboring amino acid motifs resembling previously defined c-di-GMP-binding domains, BrlR was found to bind c-di-GMP in vitro at a ratio of one c-di-GMP per two BrlR. Crosslinking assays confirmed dimer formation to be enhanced in the presence of elevated c-di-GMP levels. Our findings demonstrate BrlR to be an unusual MerR-family member in that BrlR function and expression require the secondary messenger c-di-GMP. PMID:24612375

  11. Two chain rules for divided differences and Fa`a di Bruno's formula

    NASA Astrophysics Data System (ADS)

    Floater, Michael S.; Lyche, Tom

    2007-06-01

    In this paper we derive two formulas for divided differences of a function of a function. Both formulas lead to other divided difference formulas, such as reciprocal and quotient rules. The two formulas can also be used to derive Fa`a di Bruno's formula and other formulas for higher derivatives of composite functions. We also derive a divided difference version of Fa`a di Bruno's determinant formula.

  12. Di-jet production and angular correlations in DIS at NLO

    NASA Astrophysics Data System (ADS)

    Jalilian-Marian, Jamal

    2016-03-01

    Angular correlations are a sensitive probe of the dynamics of QCD at high energy. In particular azimuthal angular correlations between two hadrons produced in Deeply Inelastic Scattering (DIS) of a virtual photon on a hadron or nucleus offer the best environment in which to investigate high gluon density (gluon saturation) effects expected to arise at small x. Here we give a progress report on our derivation of Next to Leading Order (NLO) corrections to di-jet (di-hadron) production in DIS.

  13. Dictyostelium uses the prokaryote messenger c-di-GMP to trigger stalk cell differentiation

    PubMed Central

    Chen, Zhi-hui; Schaap, Pauline

    2014-01-01

    Cyclic di-(3′:5′)-guanosine monophosphate (c-di-GMP) is a major prokaryote signalling intermediate, which is synthesized by diguanylate cyclases and triggers sessility and biofilm formation1,2. We detected the first eukaryote diguanylate cyclases (DgcAs) in all major groups of Dictyostelia. Upon food depletion, Dictyostelium discoideum amoebas collect into aggregates, which first transform into migrating slugs and next into sessile fruiting structures. These structures consist of a spherical spore mass that is supported by a column of stalk cells and a basal disk. A polyketide, DIF-1, was isolated earlier, which induces stalk-like cells in vitro3. However, its role in vivo proved recently to be restricted to basal disk formation4. Here we show that Dictyostelium DgcA produces c-di-GMP as the morphogen responsible for stalk cell differentiation. D.discoideum DgcA synthesized c-di-GMP in a GTP-dependent manner and was expressed at the slug tip, the site of stalk cell differentiation. Disruption of the DgcA gene blocked the transition from slug migration to fructification and the expression of stalk genes. Fructification and stalk formation were restored by exposing dgca- slugs to wild-type secretion products or to c-di-GMP. Moreover, c-di-GMP, but not c-di-AMP, induced stalk gene expression in dilute cell monolayers. Apart from identifying the long elusive stalk-inducing morphogen, our work also identifies the first role for c-di-GMP in eukaryotes. PMID:22864416

  14. Bacterial Signal Transduction by Cyclic Di-GMP and Other Nucleotide Second Messengers.

    PubMed

    Hengge, Regine; Gründling, Angelika; Jenal, Urs; Ryan, Robert; Yildiz, Fitnat

    2016-01-01

    The first International Symposium on c-Di-GMP Signaling in Bacteria (22 to 25 March 2015, Harnack-Haus, Berlin, Germany)brought together 131 molecular microbiologists from 17 countries to discuss recent progress in our knowledge of bacterial nucleotide second messenger signaling. While the focus was on signal input, synthesis, degradation, and the striking diversity of the modes of action of the current second messenger paradigm, i.e., cyclic di-GMP (c-di-GMP), “classics” like cAMP and (p)ppGpp were also presented, in novel facets, and more recent “newcomers,” such as c-di-AMP and c-AMP-GMP, made an impressive appearance. A number of clear trends emerged during the 30 talks, on the 71 posters, and in the lively discussions, including (i)c-di-GMP control of the activities of various ATPases and phosphorylation cascades, (ii) extensive cross talk between c-di-GMP and other nucleotide second messenger signaling pathways, and (iii) a stunning number of novel effectors for nucleotide second messengers that surprisingly include some long-known master regulators of developmental pathways. Overall, the conference made it amply clear that second messenger signaling is currently one of the most dynamic fields within molecular microbiology,with major impacts in research fields ranging from human health to microbial ecology. PMID:26055111

  15. Identification of Ligand Analogs that Control c-di-GMP Riboswitches

    PubMed Central

    Furukawa, Kazuhiro; Gu, Hongzhou; Sudarsan, Narasimhan; Hayakawa, Yoshihiro; Hyodo, Mamoru; Breaker, Ronald R.

    2012-01-01

    Riboswitches for the bacterial second messenger c-di-GMP control the expression of genes involved in numerous cellular processes such as virulence, competence, biofilm formation and flagella synthesis. Therefore, the two known c-di-GMP riboswitch classes represent promising targets for developing novel modulators of bacterial physiology. Here, we examine the binding characteristics of circular and linear c-di-GMP analogs for representatives of both class I and II c-di-GMP riboswitches derived from the pathogenic bacterium Vibrio choleae (class I) and Clostridium difficile (class II). Some compounds exhibit values for apparent dissociation constant (KD) below 1 μM and associate with riboswitch RNAs during transcription with a speed that is sufficient to influence riboswitch function. These findings are consistent with the published structural models for these riboswitches and suggest that large modifications at various positions on the ligand can be made to create novel compounds that target c-di-GMP riboswitches. Moreover, we demonstrate the potential of an engineered allosteric ribozyme for the rapid screening of chemical libraries for compounds that bind c-di-GMP riboswitches. PMID:22646696

  16. Cyclic-di-GMP signalling regulates motility and biofilm formation in Bordetella bronchiseptica

    PubMed Central

    Sisti, Federico; Ha, Dae-Gon; O'Toole, George A.; Hozbor, Daniela

    2013-01-01

    The signalling molecule bis-(3′–5′)-cyclic-dimeric guanosine monophosphate (c-di-GMP) is a central regulator of diverse cellular functions, including motility, biofilm formation, cell cycle progression and virulence, in bacteria. Multiple diguanylate cyclase and phosphodiesterase-domain-containing proteins (GGDEF and EAL/HD-GYP, respectively) modulate the levels of the second messenger c-di-GMP to transmit signals and obtain such specific cellular responses. In the genus Bordetella this c-di-GMP network is poorly studied. In this work, we evaluated the expression of two phenotypes in Bordetella bronchiseptica regulated by c-di-GMP, biofilm formation and motility, under the influence of ectopic expression of Pseudomonas aeruginosa proteins with EAL or GGDEF domains that regulates the c-di-GMP level. In agreement with previous reports for other bacteria, we observed that B. bronchiseptica is able to form biofilm and reduce its motility only when GGDEF domain protein is expressed. Moreover we identify a GGDEF domain protein (BB3576) with diguanylate cyclase activity that participates in motility and biofilm regulation in B. bronchiseptica. These results demonstrate for the first time, to our knowledge, the presence of c-di-GMP regulatory signalling in B. bronchiseptica. PMID:23475948

  17. Cyclic di-GMP acts as a cell cycle oscillator to drive chromosome replication.

    PubMed

    Lori, C; Ozaki, S; Steiner, S; Böhm, R; Abel, S; Dubey, B N; Schirmer, T; Hiller, S; Jenal, U

    2015-07-01

    Fundamental to all living organisms is the capacity to coordinate cell division and cell differentiation to generate appropriate numbers of specialized cells. Whereas eukaryotes use cyclins and cyclin-dependent kinases to balance division with cell fate decisions, equivalent regulatory systems have not been described in bacteria. Moreover, the mechanisms used by bacteria to tune division in line with developmental programs are poorly understood. Here we show that Caulobacter crescentus, a bacterium with an asymmetric division cycle, uses oscillating levels of the second messenger cyclic diguanylate (c-di-GMP) to drive its cell cycle. We demonstrate that c-di-GMP directly binds to the essential cell cycle kinase CckA to inhibit kinase activity and stimulate phosphatase activity. An upshift of c-di-GMP during the G1-S transition switches CckA from the kinase to the phosphatase mode, thereby allowing replication initiation and cell cycle progression. Finally, we show that during division, c-di-GMP imposes spatial control on CckA to install the replication asymmetry of future daughter cells. These studies reveal c-di-GMP to be a cyclin-like molecule in bacteria that coordinates chromosome replication with cell morphogenesis in Caulobacter. The observation that c-di-GMP-mediated control is conserved in the plant pathogen Agrobacterium tumefaciens suggests a general mechanism through which this global regulator of bacterial virulence and persistence coordinates behaviour and cell proliferation. PMID:25945741

  18. Cyclic di-GMP signalling and the regulation of bacterial virulence

    PubMed Central

    2013-01-01

    Signal transduction pathways involving the second messenger cyclic di-GMP [bis-(3′-5′)-cyclic di-guanosine monophosphate] occur widely in bacteria where they act to link perception of environmental or intracellular cues and signals to specific alterations in cellular function. Such alterations can contribute to bacterial lifestyle transitions including biofilm formation and virulence. The cellular levels of the nucleotide are controlled through the opposing activities of diguanylate cyclases (DGCs) and phosphodiesterases (PDEs). The GGDEF domain of DGCs catalyses the synthesis of cyclic di-GMP from GTP, whereas EAL or HD-GYP domains in different classes of PDE catalyse cyclic di-GMP degradation to pGpG and GMP. We are now beginning to understand how alterations in cyclic di-GMP exert a regulatory action through binding to diverse receptors or effectors that include a small ‘adaptor’ protein domain called PilZ, transcription factors and riboswitches. The regulatory action of enzymically active cyclic di-GMP signalling proteins is, however, not restricted to an influence on the level of nucleotide. Here, I will discuss our recent findings that highlight the role that protein–protein interactions involving these signalling proteins have in regulating functions that contribute to bacterial virulence. PMID:23704785

  19. Cyclic di-GMP signalling in the virulence and environmental adaptation of Xanthomonas campestris.

    PubMed

    Ryan, Robert P; Fouhy, Yvonne; Lucey, Jean F; Jiang, Bo-Le; He, Yong-Qiang; Feng, Jia-Xun; Tang, Ji-Liang; Dow, J Maxwell

    2007-01-01

    Cyclic di-GMP is a second messenger with a role in regulation of a range of cellular functions in diverse bacteria including the virulence of pathogens. Cellular levels of cyclic di-GMP are controlled through synthesis, catalysed by the GGDEF protein domain, and degradation by EAL or HD-GYP domains. Here we report a comprehensive study of cyclic di-GMP signalling in bacterial disease in which we examine the contribution of all proteins with GGDEF, EAL or HD-GYP domains to virulence and virulence factor production in the phytopathogen Xanthomonas campestris pathovar campestris (Xcc). Genes with significant roles in virulence to plants included those encoding proteins whose probable function is in cyclic-di-GMP synthesis as well as others (including the HD-GYP domain regulator RpfG) implicated in cyclic di-GMP degradation. Furthermore, RpfG controlled expression of a subset of these genes. A partially overlapping set of elements controlled the production of virulence factors in vitro. Other GGDEF-EAL domain proteins had no effect on virulence factor synthesis but did influence motility. These findings indicate the existence of a regulatory network that may allow Xcc to integrate information from diverse environmental inputs to modulate virulence factor synthesis as well as of cyclic di-GMP signalling systems dedicated to other specific tasks. PMID:17241199

  20. Hyperpigmentation mechanism of methyl 3,5-di-caffeoylquinate through activation of p38 and MITF induction of tyrosinase.

    PubMed

    Kim, Hyo Jung; Kim, Jin Sook; Woo, Je-Tae; Lee, Ik-Soo; Cha, Byung-Yoon

    2015-07-01

    Methyl 3,5-di-caffeoylquinate (3,5-diCQM) has been used for the treatment of various diseases in oriental medicine, but its effect on melanogenesis has not been reported yet. In this study, the molecular mechanism of 3,5-diCQM-induced melanogenesis was investigated. It was found that 3,5-diCQM induced synthesis of melanin pigments in murine B16F10 melanoma cells in a concentration-dependent manner. Treatment of cells with 3,5-diCQM for 48 h increased extracellular and intracellular melanin production and tyrosinase activity. The expressions of tyrosinase, tyrosinase-related protein 1 (TRP1), and TRP2 were up-regulated in a dose-dependent manner 48 h after 3,5-diCQM treatment. Western blot analysis showed that 3,5-diCQM increased the phosphorylation of p38 mitogen-activated protein kinase and cAMP responsive element binding as well as the expression of microphthalmia-associated transcription factor. In addition, 3,5-diCQM-stimulated cAMP production, and 3,5-diCQM-induced tyrosinase activity and melanin synthesis were attenuated by H89, a protein kinase A inhibitor. These results suggested that 3,5-diCQM-mediated activation of the p38 pathway may represent a novel approach for an effective therapy for vitiligo and hair graying. PMID:26018825

  1. An HD-domain phosphodiesterase mediates cooperative hydrolysis of c-di-AMP to affect bacterial growth and virulence

    PubMed Central

    Huynh, TuAnh Ngoc; Luo, Shukun; Pensinger, Daniel; Sauer, John-Demian; Tong, Liang; Woodward, Joshua J.

    2015-01-01

    The nucleotide cyclic di-3′,5′- adenosine monophosphate (c-di-AMP) was recently identified as an essential and widespread second messenger in bacterial signaling. Among c-di-AMP–producing bacteria, altered nucleotide levels result in several physiological defects and attenuated virulence. Thus, a detailed molecular understanding of c-di-AMP metabolism is of both fundamental and practical interest. Currently, c-di-AMP degradation is recognized solely among DHH-DHHA1 domain-containing phosphodiesterases. Using chemical proteomics, we identified the Listeria monocytogenes protein PgpH as a molecular target of c-di-AMP. Biochemical and structural studies revealed that the PgpH His-Asp (HD) domain bound c-di-AMP with high affinity and specifically hydrolyzed this nucleotide to 5′-pApA. PgpH hydrolysis activity was inhibited by ppGpp, indicating a cross-talk between c-di-AMP signaling and the stringent response. Genetic analyses supported coordinated regulation of c-di-AMP levels in and out of the host. Intriguingly, a L. monocytogenes mutant that lacks c-di-AMP phosphodiesterases exhibited elevated c-di-AMP levels, hyperinduced a host type-I IFN response, and was significantly attenuated for infection. Furthermore, PgpH homologs, which belong to the 7TMR-HD family, are widespread among hundreds of c-di-AMP synthesizing microorganisms. Thus, PgpH represents a broadly conserved class of c-di-AMP phosphodiesterase with possibly other physiological functions in this crucial signaling network. PMID:25583510

  2. Francium sources at Laboratori Nazionali di Legnaro: Design and performance

    SciTech Connect

    Stancari, G.; Veronesi, S.; Corradi, L.; Atutov, S.N.; Calabrese, R.; Dainelli, A.; Mariotti, E.; Moi, L.; Sanguinetti, S.; Tomassetti, L.

    2006-03-15

    A facility for the production of radioactive francium is operating at the laboratories of the Istituto Nazionale di Fisica Nucleare (INFN) in Legnaro, Italy. The goal is to collect a cold sample of radioactive atoms in a magneto-optical trap for studies in atomic, nuclear, and particle physics. Production of francium is achieved via the fusion-evaporation reaction {sup 197}Au({sup 18}O,kn){sup 215-k}Fr generated by a {approx}100-MeV {sup 18}O{sup 6+} beam on a thick gold target. The production target is heated to {approx}1200 K and kept at a potential of +3 kV to enhance Fr diffusion and surface desorption. Average production rates are 0.7x10{sup 6} ions/s for {sup 210}Fr with a primary beam flux of 10{sup 12} particles/s, with peaks of 2x10{sup 6} ions/s. Details are given on the design and construction of the production targets and on the measurements that characterize their performance.

  3. Laser Ablation Characterization in Laboratori Nazionali di Legnaro

    NASA Astrophysics Data System (ADS)

    Scarpa, D.; Nicolosi, P.; Franci, A.; Tomaselli, A.; Manzolaro, M.; Corradetti, S.; Vasquez, J.; Rossignoli, M.; Calderolla, M.; Monetti, A.; Andrighetto, A.; Prete, G.

    2014-04-01

    Using high power laser focalized into a target material generates plasma and it has the consequence to immediately extract and ionize atoms from the target itself. This process is the starting point to have a simple and compact ion source, usually named Laser Ion Source (LIS). This kind of sources are arising in the scenario of ion sources especially in refractory elements ions production, where the atomization of the material to ionize is the main issue because of its high evaporating temperature. These considerations and the fact that ion sources are becoming nowadays more and more important to several fields of science and technology, open an interesting line of research that our group at Laboratori Nazionali di Legnaro wants to investigate. Experiment involves characterization of produced ions by measuring charge state and amount of ions created. Measurements will be performed with several power densities and varying ions collector distance and potential respect to the target. These simple experiments are the necessary preliminary steps to characterize the system and to start a solid future development onto possible different and effective ways to perform ions sources using laser.

  4. Biotransformation of di(2-ethylhexyl)phthalate by rainbow trout

    SciTech Connect

    Barron, M.G.; Hayton, W.L.

    1995-05-01

    The biotransformation of di(2-ethylhexyl)phthalate (DEHP) was studied in rainbow trout (Oncorhynchus mykiss) following intravascular administration. Methyl-esterified metabolites were identified using rodent-derived standards and non-linear gradient elution HPLC; metabolites were confirmed by gas chromatography. Similarities between the biotransformation of DEHP by rainbow trout and mammalian species included (a) mono-ethylhexyl phthalate (MEHP) appeared to be the obligatory first step in DEHP metabolism; (b) the phthalate ring was not oxidized; (c) phthalic acid was a minor metabolite; and (d) several metabolites contained multiple oxidations of the 2-ethylhexyl moiety of MEHP. No metabolites unique to rainbow trout were identified. However, fewer oxidized metabolites were identified in rainbow trout than in mammalian species, possibly due to limited mitochondrial metabolism of MEHP in rainbow trout. The amount of biliary MEHP glucuronide after intravascular administration of DEHP was substantially less than reported in rainbow trout exposed to DEHP via the water. Results confirmed that DEHP metabolism in rainbow trout proceeds by initial rapid formation of MEHP, followed by excretion or extensive oxidation by microsomal P450.

  5. 40 CFR 721.10325 - Cyclosilazanes, di-Me, Me hydrogen, polymers with di-Me, Me hydrogen silazanes, reaction products...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ..., reaction products with 3-(triethoxysilyl)-1-propanamine. (a) Chemical substance and significant new uses..., polymers with di-Me, Me hydrogen silazanes, reaction products with 3-(triethoxysilyl)-1-propanamine. 721... SUBSTANCES CONTROL ACT SIGNIFICANT NEW USES OF CHEMICAL SUBSTANCES Significant New Uses for Specific...

  6. 3,6-diHydroxyflavone/bovine serum albumin interaction in cyclodextrin medium: Absorption and emission monitoring

    NASA Astrophysics Data System (ADS)

    Voicescu, Mariana; Bandula, Rodica

    2015-03-01

    Photophysical properties of a bioactive flavonol which can be used as a model for polyhydroxylated natural flavonols, 3,6-diHydroxyflavone (3,6-diHF) in cyclodextrins (CDs)/bovine serum albumin (BSA) systems have been studied by absorption and fluorescence spectroscopy. The influence of CDs nature and of the different molar ratios BSA/CDs on the fluorescent characteristics of 3,6-diHF, and on the excited - state intramolecular proton transfer (ESIPT) process were studied. Quantitative information on the interaction between 3,6-diHF and BSA in CDs medium, were estimated. The influence of temperature (25-60 °C range) on the intrinsic fluorescence of BSA in 3,6-diHF/BSA/CDs systems, was investigated. The results are discussed with relevance to 3,6-diHF as a potential sensitive fluorescence probe in the systems of biological interest.

  7. Nuclease-resistant c-di-AMP derivatives that differentially recognize RNA and protein receptors

    PubMed Central

    Meehan, Robert E.; Torgerson, Chad D.; Gaffney, Barbara L.; Jones, Roger A.; Strobel, Scott A.

    2016-01-01

    The ability of bacteria to sense environmental cues and adapt is essential for their survival. The use of second-messenger signaling molecules to translate these cues into a physiological response is a common mechanism employed by bacteria. The second messenger 3’-5’-cyclic diadenosine monophosphate (c-di-AMP) has been linked to a diverse set of biological processes involved in maintaining cell viability and homeostasis, as well as pathogenicity. A complex network of both protein and RNA receptors inside the cell activate specific pathways and mediate phenotypic outputs in response to c-di-AMP. Structural analysis of these RNA and protein receptors has revealed the different recognition elements employed by these effectors to bind the same small molecule. Herein, using a series of c-di-AMP analogs, we probed the interactions made with a riboswitch and a phosphodiesterase protein to identify the features important for c-di-AMP binding and recognition. We found that the ydaO riboswitch binds c-di-AMP in two discrete sites with near identical affinity and a Hill coefficient of 1.6. The ydaO riboswitch distinguishes between c-di-AMP and structurally related second messengers by discriminating against an amine at the C2 position, more than a carbonyl at the C6 position. We also identified phosphate-modified analogs that bind both the ydaO RNA and GdpP protein with high affinity, while symmetrically-modified ribose analogs exhibited a substantial decrease in ydaO affinity, but retained high affinity for GdpP. These ligand modifications resulted in increased resistance to enzyme-catalyzed hydrolysis by the GdpP enzyme. Together, these data suggest that these c-di-AMP analogs could be useful as chemical tools to specifically target subsections of the second-messenger signaling pathways. PMID:26789423

  8. Pyrosequencing with di-base addition for single nucleotide polymorphism genotyping.

    PubMed

    Pu, Dan; Mao, Chengguang; Cui, Lunbiao; Shi, Zhiyang; Xiao, Pengfeng

    2016-05-01

    We develop color code-based pyrosequencing with di-base addition for analysis of single nucleotide polymorphisms (SNPs). When a di-base is added into the polymerization, one or several two-color code(s) containing the type and the number of incorporated nucleotides will be produced. The code information obtained in a single run is useful to genotype SNPs as each allelic variant will give a specific pattern compared to the two other variants. Special care has to be taken while designing the di-base dispensation order. Here, we present a detailed protocol for establishing sequence-specific di-base addition to avoid nonsynchronous extension at the SNP sites. By using this technology, as few as 50 copies of DNA templates were accurately sequenced. Higher signals were produced and thus a relatively lower sample amount was required. Furthermore, the read length of per flow was increased, making simultaneous identification of multiple SNPs in a single sequencing run possible. Validation of the method was performed by using templates with two SNPs covering 37 bp and with three SNPs covering 58 bp as well as 82 bp. These SNPs were successfully genotyped by using only a sequencing primer in a single PCR/sequencing run. Our results demonstrated that this technology could be potentially developed into a powerful methodology to accurately determine SNPs so as to diagnose clinical settings. Graphical Abstract Conventional pyrosequencing adds one base (A, G, C, or T) at a time to determine the SNP site (left). Pyrosequencing with di-base addition adds di-base AG, AC, AT, CT, GC or GT at a time to determine the SNP site (right). Higher signals at SNP site will be produced due to the addition of di-bases. PMID:26935928

  9. Nuclease-Resistant c-di-AMP Derivatives That Differentially Recognize RNA and Protein Receptors.

    PubMed

    Meehan, Robert E; Torgerson, Chad D; Gaffney, Barbara L; Jones, Roger A; Strobel, Scott A

    2016-02-16

    The ability of bacteria to sense environmental cues and adapt is essential for their survival. The use of second-messenger signaling molecules to translate these cues into a physiological response is a common mechanism employed by bacteria. The second messenger 3'-5'-cyclic diadenosine monophosphate (c-di-AMP) has been linked to a diverse set of biological processes involved in maintaining cell viability and homeostasis, as well as pathogenicity. A complex network of both protein and RNA receptors inside the cell activates specific pathways and mediates phenotypic outputs in response to c-di-AMP. Structural analysis of these RNA and protein receptors has revealed the different recognition elements employed by these effectors to bind the same small molecule. Herein, using a series of c-di-AMP analogues, we probed the interactions made with a riboswitch and a phosphodiesterase protein to identify the features important for c-di-AMP binding and recognition. We found that the ydaO riboswitch binds c-di-AMP in two discrete sites with near identical affinity and a Hill coefficient of 1.6. The ydaO riboswitch distinguishes between c-di-AMP and structurally related second messengers by discriminating against an amine at the C2 position more than a carbonyl at the C6 position. We also identified phosphate-modified analogues that bind both the ydaO RNA and GdpP protein with high affinity, whereas symmetrically modified ribose analogues exhibited a substantial decrease in ydaO affinity but retained high affinity for GdpP. These ligand modifications resulted in increased resistance to enzyme-catalyzed hydrolysis by the GdpP enzyme. Together, these data suggest that these c-di-AMP analogues could be useful as chemical tools to specifically target subsections of second-messenger signaling pathways. PMID:26789423

  10. Structural and Biochemical Determinants of Ligand Binding by the c-di-GMP Riboswitch

    SciTech Connect

    Smith, K.; Lipchock, S; Livingston,; Shanahan, C; Strobel, S

    2010-01-01

    The bacterial second messenger c-di-GMP is used in many species to control essential processes that allow the organism to adapt to its environment. The c-di-GMP riboswitch (GEMM) is an important downstream target in this signaling pathway and alters gene expression in response to changing concentrations of c-di-GMP. The riboswitch selectively recognizes its second messenger ligand primarily through contacts with two critical nucleotides. However, these two nucleotides are not the most highly conserved residues within the riboswitch sequence. Instead, nucleotides that stack with c-di-GMP and that form tertiary RNA contacts are the most invariant. Biochemical and structural evidence reveals that the most common natural variants are able to make alternative pairing interactions with both guanine bases of the ligand. Additionally, a high-resolution (2.3 {angstrom}) crystal structure of the native complex reveals that a single metal coordinates the c-di-GMP backbone. Evidence is also provided that after transcription of the first nucleotide on the 3{prime}-side of the P1 helix, which is predicted to be the molecular switch, the aptamer is functional for ligand binding. Although large energetic effects occur when several residues in the RNA are altered, mutations at the most conserved positions, rather than at positions that base pair with c-di-GMP, have the most detrimental effects on binding. Many mutants retain sufficient c-di-GMP affinity for the RNA to remain biologically relevant, which suggests that this motif is quite resilient to mutation.

  11. De novo asymmetric synthesis of oligo-rhamno di- and tri-saccharides related to the anthrax tetrasaccharide

    PubMed Central

    Wang, Hua-Yu Leo; Guo, Haibing; O’Doherty, George A.

    2013-01-01

    An asymmetric synthesis of the di- and trisaccharide portion of the naturally occurring anthrax tetrasaccharide from acetylfuran has been developed. The construction of the di- and trisaccharide subunits is based upon our previously disclosed route to anthrax tetrasaccharide. The approach uses iterative diastereoselective palladium-catalyzed glycosylations, Luche reductions, diastereoselective dihydroxylations, and regioselective protections for the assembly of the rhamno- di- and tri-saccharide. The route was also modified for the preparation of the mixed D-/L-disaccharide analogue. PMID:23794755

  12. Comment on "Competition for consciousness among visual events: the psychophysics of reentrant visual processes" (Di Lollo, Enns, & Rensink, 2000).

    PubMed

    Francis, Gregory; Hermens, Frouke

    2002-12-01

    V. Di Lolo, J. T. Enns, and R. A. Rensink (2000) reported properties of masking that they claimed were inconsistent with all current models. The current authors show, through computer simulation, that many current models can account for V. Di Lollo et al.'s (2000) data. Although V. Di Lollo et al. (2000) argued that their data could be accounted for only with models that incorporate reentrant processing, the current authors show that reentrant processing is not necessary. PMID:12500865

  13. DhhP, a cyclic di-AMP phosphodiesterase of Borrelia burgdorferi, is essential for cell growth and virulence.

    PubMed

    Ye, Meiping; Zhang, Jun-Jie; Fang, Xin; Lawlis, Gavin B; Troxell, Bryan; Zhou, Yan; Gomelsky, Mark; Lou, Yongliang; Yang, X Frank

    2014-05-01

    Cyclic di-AMP (c-di-AMP) is a recently discovered second messenger in bacteria. Most of work on c-di-AMP signaling has been done in Gram-positive bacteria, firmicutes, and actinobacteria, where c-di-AMP signaling pathways affect potassium transport, cell wall structure, and antibiotic resistance. Little is known about c-di-AMP signaling in other bacteria. Borrelia burgdorferi, the causative agent of Lyme disease, is a spirochete that has a Gram-negative dual membrane. In this study, we demonstrated that B. burgdorferi BB0619, a DHH-DHHA1 domain protein (herein designated DhhP), functions as c-di-AMP phosphodiesterase. Recombinant DhhP hydrolyzed c-di-AMP to pApA in a Mn(2+)- or Mg(2+)-dependent manner. In contrast to c-di-AMP phosphodiesterases reported thus far, DhhP appears to be essential for B. burgdorferi growth both in vitro and in the mammalian host. Inactivation of the chromosomal dhhP gene could be achieved only in the presence of a plasmid-encoded inducible dhhP gene. The conditional dhhP mutant had a dramatic increase in intracellular c-di-AMP level in comparison to the isogenic wild-type strain. Unlike what has been observed in Gram-positive bacteria, elevated cellular c-di-AMP in B. burgdorferi did not result in an increased resistance to ?-lactamase antibiotics, suggesting that c-di-AMP's functions in spirochetes differ from those in Gram-positive bacteria. In addition, the dhhP mutant was defective in induction of the ?(S) factor, RpoS, and the RpoS-dependent outer membrane virulence factor OspC, which uncovers an important role of c-di-AMP in B. burgdorferi virulence. PMID:24566626

  14. DhhP, a Cyclic di-AMP Phosphodiesterase of Borrelia burgdorferi, Is Essential for Cell Growth and Virulence

    PubMed Central

    Ye, Meiping; Zhang, Jun-Jie; Fang, Xin; Lawlis, Gavin B.; Troxell, Bryan; Zhou, Yan; Gomelsky, Mark

    2014-01-01

    Cyclic di-AMP (c-di-AMP) is a recently discovered second messenger in bacteria. Most of work on c-di-AMP signaling has been done in Gram-positive bacteria, firmicutes, and actinobacteria, where c-di-AMP signaling pathways affect potassium transport, cell wall structure, and antibiotic resistance. Little is known about c-di-AMP signaling in other bacteria. Borrelia burgdorferi, the causative agent of Lyme disease, is a spirochete that has a Gram-negative dual membrane. In this study, we demonstrated that B. burgdorferi BB0619, a DHH-DHHA1 domain protein (herein designated DhhP), functions as c-di-AMP phosphodiesterase. Recombinant DhhP hydrolyzed c-di-AMP to pApA in a Mn2+- or Mg2+-dependent manner. In contrast to c-di-AMP phosphodiesterases reported thus far, DhhP appears to be essential for B. burgdorferi growth both in vitro and in the mammalian host. Inactivation of the chromosomal dhhP gene could be achieved only in the presence of a plasmid-encoded inducible dhhP gene. The conditional dhhP mutant had a dramatic increase in intracellular c-di-AMP level in comparison to the isogenic wild-type strain. Unlike what has been observed in Gram-positive bacteria, elevated cellular c-di-AMP in B. burgdorferi did not result in an increased resistance to β-lactamase antibiotics, suggesting that c-di-AMP's functions in spirochetes differ from those in Gram-positive bacteria. In addition, the dhhP mutant was defective in induction of the σS factor, RpoS, and the RpoS-dependent outer membrane virulence factor OspC, which uncovers an important role of c-di-AMP in B. burgdorferi virulence. PMID:24566626

  15. Boosted di-boson from a mixed heavy stop

    SciTech Connect

    Ghosh, Diptimoy

    2013-12-01

    The lighter mass eigenstate ($\\widetilde{t}_1$) of the two top squarks, the scalar superpartners of the top quark, is extremely difficult to discover if it is almost degenerate with the lightest neutralino ($\\widetilde{\\chi}_1^0$), the lightest and stable supersymmetric particle in the R-parity conserving supersymmetry. The current experimental bound on $\\widetilde{t}_1$ mass in this scenario stands only around 200 GeV. For such a light $\\widetilde{t}_1$, the heavier top squark ($\\widetilde{t}_2$) can also be around the TeV scale. Moreover, the high value of the higgs ($h$) mass prefers the left and right handed top squarks to be highly mixed allowing the possibility of a considerable branching ratio for $\\widetilde{t}_2 \\to \\widetilde{t}_1 h$ and $\\widetilde{t}_2 \\to \\widetilde{t}_1 Z$. In this paper, we explore the above possibility together with the pair production of $\\widetilde{t}_2$ $\\widetilde{t}_2^*$ giving rise to the spectacular di-boson + missing transverse energy final state. For an approximately 1 TeV $\\widetilde{t}_2$ and a few hundred GeV $\\widetilde{t}_1$ the final state particles can be moderately boosted which encourages us to propose a novel search strategy employing the jet substructure technique to tag the boosted $h$ and $Z$. The reconstruction of the $h$ and $Z$ momenta also allows us to construct the stransverse mass $M_{T2}$ providing an additional efficient handle to fight the backgrounds. We show that a 4--5$\\sigma$ signal can be observed at the 14 TeV LHC for $\\sim$ 1 TeV $\\widetilde{t}_2$ with 100 fb$^{-1}$ integrated luminosity.

  16. DiMES divertor erosion experiments on DIII-D

    SciTech Connect

    Whyte, D.G.; Brooks, J.N.; Wong, C.P.C.; West, W.P.; Bastasz, R.; Wampler, W.R.; Rubinstein, J.

    1996-06-01

    The DiMES (Divertor Material Evaluation Studies) mechanism allows insertion of material samples to the lower divertor floor of the DIII-D tokamak. The main purpose of these studies is to measure erosion rates and redeposition mechanisms under tokamak divertor plasma conditions in order to obtain a physical understanding of the erosion/redeposition processes and to determine its implications for fusion power plant plasma facing components. Thin metal films of Be, W, V, and Mo, were deposited on a Si depth-marked graphite sample and exposed to the steady-state outer strike point on DIII-D. A variety of surface analysis techniques are used to determine the erosion/redeposition of the metals and the carbon after 5--15 seconds of exposure. These short exposure times ensure controlled exposure conditions and the extensive array of DIII-D divertor diagnostics provide a well characterized plasma for modeling efforts. Erosion rates and redeposition lengths are found to decrease with the atomic number of the metallic species, as expected. Under these conditions, the peak net erosion rate for carbon is {approximately} 4 nm/s, with the erosion following the ion flux profile. Comparisons of the measured carbon erosion with REDEP code calculations show good agreement for both the absolute net erosion rate and its spatial variation. Measured erosion rates of the metals are smaller than predicted for sputtering from a bare metal surface, apparently due to effects of carbon deposition on the metal surface. Visible spectroscopic measurements of singly ionized Be have determined that the erosion process reaches steady-state during the exposure.

  17. Liposomes loaded with a STING pathway ligand, cyclic di-GMP, enhance cancer immunotherapy against metastatic melanoma.

    PubMed

    Nakamura, Takashi; Miyabe, Hiroko; Hyodo, Mamoru; Sato, Yusuke; Hayakawa, Yoshihiro; Harashima, Hideyoshi

    2015-10-28

    Malignant melanomas escape immunosurveillance via the loss/down-regulation of MHC-I expression. Natural killer (NK) cells have the potential to function as essential effector cells for eliminating melanomas. Cyclic di-GMP (c-di-GMP), a ligand of the stimulator of interferon genes (STING) signal pathway, can be thought of as a new class of adjuvant against cancer. However, it is yet to be tested, because technologies for delivering c-di-GMP to the cytosol are required. Herein, we report that c-di-GMP efficiently activates NK cells and induces antitumor effects against malignant melanomas when loaded in YSK05 lipid containing liposomes, by assisting in the efficient delivery of c-di-GMP to the cytosol. The intravenous administration of c-di-GMP encapsulated within YSK05-liposomes (c-di-GMP/YSK05-Lip) into mice efficiently induced the production of type I interferon (IFN) as well as the activation of NK cells, resulting in a significant antitumor effect in a lung metastasis mouse model using B16-F10. This antitumor effect was dominated by NK cells. The infiltration of NK cells was observed in the lungs with B16-F10 melanomas. These findings indicate that the c-di-GMP/YSK05-Lip induces MHC-I non-restricted antitumor immunity mediated by NK cells. Consequently, c-di-GMP/YSK05-Lip represents a potentially new adjuvant system for use in immunotherapy against malignant melanomas. PMID:26282097

  18. Bilaterally Symmetric Populations of Chicken dI1 (Commissural) Axons Cross the Floor Plate Independently of Each Other

    PubMed Central

    Phan, Keith D.; Butler, Samantha J.

    2013-01-01

    Axons use temporal and directional guidance cues at intermediate targets to set the rate and direction of growth towards their synaptic targets. Our recent studies have shown that disrupting the temporal guidance process, by unilaterally accelerating the rate at which spinal dI1 (commissural) axons grow, resulted in turning errors both in the ventral spinal cord and after crossing the floor plate. Here we investigate a mechanistic explanation for these defects: the accelerated dI1 axons arrive in the ventral spinal cord before necessary fasciculation cues from incoming dI1 axons from the opposite side of the spinal cord. The identification of such an interaction would support a model of selective fasciculation whereby the pioneering dI1 axons serve as guides for the processes of the bilaterally symmetrical population of dI1 neurons. To test this model, we first developed the ability to “double” in ovo electroporate the embryonic chicken spinal cord to independently manipulate the rate of growth of the two bilateral populations of dI1 axons. Second, we examined the requirement for a putative bilateral interaction by unilaterally ablating the dI1 population in cultured explants of chicken embryonic spinal cord. Surprisingly, we find no evidence for a bilateral dI1 axon interaction, rather dI1 axons appear to project independently of each other. PMID:23646165

  19. Diethyl 4-(2-meth-oxy-phen-yl)-2,6-di-methyl-1,4-di-hydro-pyridine-3,5-di-carboxyl-ate.

    PubMed

    Wang, Ke; Wang, Yifeng; Yao, Minjie; Xu, Danqian

    2013-05-01

    In the title compound, C20H25NO5, the di-hydro-pyridine ring adopts a flattened boat conformation. The meth-oxy-phenyl ring is almost perpendicular to the mean plane of the pyridine ring [dihedral angle = 88.42 (3)°]. The two carbonyl units adopt a synperiplanar conformation with respect to the double bonds in the di-hydro-pyridine ring. In the crystal, mol-ecules are connected by N-H⋯O hydrogen bonds into R 4 (4)(24) tetra-meric rings. A region of disordered electron density, located at the center of four adjacent mol-ecules, was treated with the SQUEEZE routine in PLATON [Spek (2009 ▶). Acta Cryst. D65, 148-155]. It is probably the result of traces of the solvent of crystallization and was not taken into account during the structure refinement. PMID:23723929

  20. Systematic Identification of Cyclic-di-GMP Binding Proteins in Vibrio cholerae Reveals a Novel Class of Cyclic-di-GMP-Binding ATPases Associated with Type II Secretion Systems.

    PubMed

    Roelofs, Kevin G; Jones, Christopher J; Helman, Sarah R; Shang, Xiaoran; Orr, Mona W; Goodson, Jonathan R; Galperin, Michael Y; Yildiz, Fitnat H; Lee, Vincent T

    2015-10-01

    Cyclic-di-GMP (c-di-GMP) is a ubiquitous bacterial signaling molecule that regulates a variety of complex processes through a diverse set of c-di-GMP receptor proteins. We have utilized a systematic approach to identify c-di-GMP receptors from the pathogen Vibrio cholerae using the Differential Radial Capillary Action of Ligand Assay (DRaCALA). The DRaCALA screen identified a majority of known c-di-GMP binding proteins in V. cholerae and revealed a novel c-di-GMP binding protein, MshE (VC0405), an ATPase associated with the mannose sensitive hemagglutinin (MSHA) type IV pilus. The known c-di-GMP binding proteins identified by DRaCALA include diguanylate cyclases, phosphodiesterases, PilZ domain proteins and transcription factors VpsT and VpsR, indicating that the DRaCALA-based screen of open reading frame libraries is a feasible approach to uncover novel receptors of small molecule ligands. Since MshE lacks the canonical c-di-GMP-binding motifs, a truncation analysis was utilized to locate the c-di-GMP binding activity to the N-terminal T2SSE_N domain. Alignment of MshE homologs revealed candidate conserved residues responsible for c-di-GMP binding. Site-directed mutagenesis of these candidate residues revealed that the Arg9 residue is required for c-di-GMP binding. The ability of c-di-GMP binding to MshE to regulate MSHA dependent processes was evaluated. The R9A allele, in contrast to the wild type MshE, was unable to complement the ΔmshE mutant for the production of extracellular MshA to the cell surface, reduction in flagella swimming motility, attachment to surfaces and formation of biofilms. Testing homologs of MshE for binding to c-di-GMP identified the type II secretion ATPase of Pseudomonas aeruginosa (PA14_29490) as a c-di-GMP receptor, indicating that type II secretion and type IV pili are both regulated by c-di-GMP. PMID:26506097

  1. Systematic Identification of Cyclic-di-GMP Binding Proteins in Vibrio cholerae Reveals a Novel Class of Cyclic-di-GMP-Binding ATPases Associated with Type II Secretion Systems

    PubMed Central

    Shang, Xiaoran; Orr, Mona W.; Goodson, Jonathan R.; Galperin, Michael Y.; Yildiz, Fitnat H.; Lee, Vincent T.

    2015-01-01

    Cyclic-di-GMP (c-di-GMP) is a ubiquitous bacterial signaling molecule that regulates a variety of complex processes through a diverse set of c-di-GMP receptor proteins. We have utilized a systematic approach to identify c-di-GMP receptors from the pathogen Vibrio cholerae using the Differential Radial Capillary Action of Ligand Assay (DRaCALA). The DRaCALA screen identified a majority of known c-di-GMP binding proteins in V. cholerae and revealed a novel c-di-GMP binding protein, MshE (VC0405), an ATPase associated with the mannose sensitive hemagglutinin (MSHA) type IV pilus. The known c-di-GMP binding proteins identified by DRaCALA include diguanylate cyclases, phosphodiesterases, PilZ domain proteins and transcription factors VpsT and VpsR, indicating that the DRaCALA-based screen of open reading frame libraries is a feasible approach to uncover novel receptors of small molecule ligands. Since MshE lacks the canonical c-di-GMP-binding motifs, a truncation analysis was utilized to locate the c-di-GMP binding activity to the N-terminal T2SSE_N domain. Alignment of MshE homologs revealed candidate conserved residues responsible for c-di-GMP binding. Site-directed mutagenesis of these candidate residues revealed that the Arg9 residue is required for c-di-GMP binding. The ability of c-di-GMP binding to MshE to regulate MSHA dependent processes was evaluated. The R9A allele, in contrast to the wild type MshE, was unable to complement the ΔmshE mutant for the production of extracellular MshA to the cell surface, reduction in flagella swimming motility, attachment to surfaces and formation of biofilms. Testing homologs of MshE for binding to c-di-GMP identified the type II secretion ATPase of Pseudomonas aeruginosa (PA14_29490) as a c-di-GMP receptor, indicating that type II secretion and type IV pili are both regulated by c-di-GMP. PMID:26506097

  2. ANALYSIS OF SPIN-ORBIT MISALIGNMENT IN THE ECLIPSING BINARY DI HERCULIS

    SciTech Connect

    Philippov, Alexander A.; Rafikov, Roman R.

    2013-05-10

    The eclipsing binary DI Herculis (DI Her) is known to exhibit anomalously slow apsidal precession below the rate predicted by general relativity. Recent measurements of the Rossiter-McLaughlin effect indicate that stellar spins in DI Her are almost orthogonal to the orbital angular momentum, which explains the anomalous precession in agreement with the earlier theoretical suggestion by Shakura. However, these measurements yield only projections of the spin-orbit angles onto the sky plane, leaving the spin projection onto our line of sight unconstrained. Here we describe a method for determining the full three-dimensional spin orientation of the binary components relying on the use of the gravity-darkening effect, which is significant for the rapidly rotating stars in DI Her. Gravity darkening gives rise to a nonuniform brightness distribution over the stellar surface, the pattern of which depends on the stellar spin orientation. Using archival photometric data obtained during multiple eclipses over several decades, we are able to constrain the unknown spin angles in DI Her with this method, finding that the spin axes of both stars lie close to the plane of the sky. Our procedure fully accounts for the precession of stellar spins over the long time span of observations.

  3. Structural Insight into the Mechanism of c-di-GMP hydrolysis by EAL domain phosphodiesterases.

    SciTech Connect

    Tchigvintsev, A.; Xu, X.; Singer, A.; Chang, C.; Brown, G.; Proudfoot, M.; Cui, H.; Flick, R.; Anderson, W.; Joachimiak, A.; Galperin, M.; Savchenko, A.; Yakunin, A.; Biosciences Division; Univ. of Toronto; Northwestern Univ.; NIH

    2010-08-01

    Cyclic diguanylate (or bis-(3'-5') cyclic dimeric guanosine monophosphate; c-di-GMP) is a ubiquitous second messenger that regulates diverse cellular functions, including motility, biofilm formation, cell cycle progression, and virulence in bacteria. In the cell, degradation of c-di-GMP is catalyzed by highly specific EAL domain phosphodiesterases whose catalytic mechanism is still unclear. Here, we purified 13 EAL domain proteins from various organisms and demonstrated that their catalytic activity is associated with the presence of 10 conserved EAL domain residues. The crystal structure of the TBD1265 EAL domain was determined in free state (1.8 {angstrom}) and in complex with c-di-GMP (2.35 {angstrom}), and unveiled the role of conserved residues in substrate binding and catalysis. The structure revealed the presence of two metal ions directly coordinated by six conserved residues, two oxygens of c-di-GMP phosphate, and potential catalytic water molecule. Our results support a two-metal-ion catalytic mechanism of c-di-GMP hydrolysis by EAL domain phosphodiesterases.

  4. Tetrameric c-di-GMP Mediates Effective Transcription Factor Dimerization to Control Streptomyces Development

    PubMed Central

    Tschowri, Natalia; Schumacher, Maria A.; Schlimpert, Susan; Chinnam, Naga babu; Findlay, Kim C.; Brennan, Richard G.; Buttner, Mark J.

    2014-01-01

    Summary The cyclic dinucleotide c-di-GMP is a signaling molecule with diverse functions in cellular physiology. Here, we report that c-di-GMP can assemble into a tetramer that mediates the effective dimerization of a transcription factor, BldD, which controls the progression of multicellular differentiation in sporulating actinomycete bacteria. BldD represses expression of sporulation genes during vegetative growth in a manner that depends on c-di-GMP-mediated dimerization. Structural and biochemical analyses show that tetrameric c-di-GMP links two subunits of BldD through their C-terminal domains, which are otherwise separated by ∼10 Å and thus cannot effect dimerization directly. Binding of the c-di-GMP tetramer by BldD is selective and requires a bipartite RXD-X8-RXXD signature. The findings indicate a unique mechanism of protein dimerization and the ability of nucleotide signaling molecules to assume alternative oligomeric states to effect different functions. PMID:25171413

  5. Engineering a Novel c-di-GMP-Binding Protein for Biofilm Dispersal

    PubMed Central

    Ma, Qun; Yang, Zhonghua; Pu, Mingming; Peti, Wolfgang; Wood, Thomas K.

    2010-01-01

    SUMMARY Bacteria prefer to grow attached to themselves or an interface, and it is important for an array of applications to make biofilms disperse. Here we report simultaneously the discovery and protein engineering of BdcA (formerly YjgI) for biofilm dispersal using the universal signal 3,5-cyclic diguanylic acid (c-di-GMP). The bdcA deletion reduced biofilm dispersal, and production of BdcA increased biofilm dispersal to wild-type levels. Since BdcA increases motility and extracellular DNA production while decreasing exopolysaccharide, cell length, and aggregation, we reasoned that BdcA decreases the concentration of c-di-GMP, the intracellular messenger that controls cell motility through flagellar rotation and biofilm formation through synthesis of curli and cellulose. Consistently, c-di-GMP levels increase upon deleting bdcA, and purified BdcA binds c-di-GMP but does not act as a phosphodiesterase. Additionally, BdcR (formerly YjgJ) is a negative regulator of bdcA. To increase biofilm dispersal, we used protein engineering to evolve BdcA for greater c-di-GMP binding and found that the single amino acid change E50Q causes nearly complete removal of biofilms via dispersal without affecting initial biofilm formation. PMID:21059164

  6. Crystal and molecular structure of the sulfhydryl protease calotropin DI at 3.2 A resolution.

    PubMed

    Heinemann, U; Pal, G P; Hilgenfeld, R; Saenger, W

    1982-11-15

    The three-dimensional structure of the sulfhydryl protease calotropin DI from the madar plant, Calotropis gigantea, has been determined at 3.2 A resolution using the multiple isomorphous replacement method with five heavy atom derivatives. A Fourier synthesis based on protein phases with a mean figure of merit of 0.857 was used for model building. The polypeptide backbone of calotropin DI is folded to form two distinct lobes, one of which is comprised mainly of alpha-helices, while the other is characterized by a system of all antiparallel pleated sheets. The overall molecular architecture closely resembles those found in the sulfhydryl proteases papain and actinidin. Despite the unknown amino acid sequence of calotropin DI a number of residues around its active center could be identified. These amino acid side-chains were found in a similar arrangement as the corresponding ones in papain and actinidin. The polypeptide chain between residues 1 and 18 of calotropin DI folds in a unique manner, providing a possible explanation for the unusual inability of calotropin DI to hydrolyze those synthetic substrates that papain and actinidin act upon. PMID:6759664

  7. Cyclic di-GMP Sensing via the Innate Immune Signaling Protein STING

    PubMed Central

    Yin, Qian; Tian, Yuan; Kabaleeswaran, Venkataraman; Jiang, Xiaomo; Tu, Daqi; Eck, Michael J.; Chen, Zhijian J.; Wu, Hao

    2013-01-01

    SUMMARY Detection of foreign materials is the first step of successful immune responses. Stimulator of interferon genes (STING) was shown to directly bind cyclic diguanylate monophosphate (c-di-GMP), a bacterial second messenger, and to elicit strong interferon responses. Here we elucidate the structural features of the cytosolic c-di-GMP binding domain (CBD) of STING and its complex with c-di-GMP. The CBD exhibits an α + β fold and is a dimer in the crystal and in solution. Surprisingly, one c-di-GMP molecule binds to the central crevice of a STING dimer, using a series of stacking and hydrogen bonding interactions. We show that STING is autoinhibited by an intramolecular interaction between the CBD and the C-terminal tail (CTT) and that c-di-GMP releases STING from this autoinhibition by displacing the CTT. The structures provide a remarkable example of pathogen-host interactions in which a unique microbial molecule directly engages the innate immune system. PMID:22705373

  8. MOZ regulates the Tbx1 locus, and Moz mutation partially phenocopies DiGeorge syndrome.

    PubMed

    Voss, Anne K; Vanyai, Hannah K; Collin, Caitlin; Dixon, Mathew P; McLennan, Tamara J; Sheikh, Bilal N; Scambler, Peter; Thomas, Tim

    2012-09-11

    DiGeorge syndrome, caused by a 22q11 microdeletion or mutation of the TBX1 gene, varies in severity greatly, even among monozygotic twins. Epigenetic phenomena have been invoked to explain phenotypic differences in individuals of identical genetic composition, although specific chromatin modifications relevant to DiGeorge syndrome are elusive. Here we show that lack of the histone acetyltransferase MOZ (MYST3/KAT6A) phenocopies DiGeorge syndrome, and the MOZ complex occupies the Tbx1 locus, promoting its expression and histone 3 lysine 9 acetylation. Importantly, DiGeorge syndrome-like anomalies are present in mice with homozygous mutation of Moz and in heterozygous Moz mutants when combined with Tbx1 haploinsufficiency or oversupply of retinoic acid. Conversely, a Tbx1 transgene rescues the heart phenotype in Moz mutants. Our data reveal a molecular mechanism for a specific chromatin modification of the Tbx1 locus intersecting with an environmental determinant, modeling variability in DiGeorge syndrome. PMID:22921202

  9. MOZ Regulates the Tbx1 Locus, and Moz Mutation Partially Phenocopies DiGeorge Syndrome

    PubMed Central

    Voss, Anne K.; Vanyai, Hannah K.; Collin, Caitlin; Dixon, Mathew P.; McLennan, Tamara J.; Sheikh, Bilal N.; Scambler, Peter; Thomas, Tim

    2012-01-01

    Summary DiGeorge syndrome, caused by a 22q11 microdeletion or mutation of the TBX1 gene, varies in severity greatly, even among monozygotic twins. Epigenetic phenomena have been invoked to explain phenotypic differences in individuals of identical genetic composition, although specific chromatin modifications relevant to DiGeorge syndrome are elusive. Here we show that lack of the histone acetyltransferase MOZ (MYST3/KAT6A) phenocopies DiGeorge syndrome, and the MOZ complex occupies the Tbx1 locus, promoting its expression and histone 3 lysine 9 acetylation. Importantly, DiGeorge syndrome-like anomalies are present in mice with homozygous mutation of Moz and in heterozygous Moz mutants when combined with Tbx1 haploinsufficiency or oversupply of retinoic acid. Conversely, a Tbx1 transgene rescues the heart phenotype in Moz mutants. Our data reveal a molecular mechanism for a specific chromatin modification of the Tbx1 locus intersecting with an environmental determinant, modeling variability in DiGeorge syndrome. PMID:22921202

  10. [L'influenza del genere sui sintomi dello spettro d'ansia sociale in un campione di studenti universitari].

    PubMed

    Dell'Osso, Liliana; Abelli, Marianna; Pini, Stefano; Carpita, Barbara; Carlini, Marina; Mengali, Francesco; Tognetti, Rosalba; Rivetti, Francesco; Massimetti, Gabriele

    2015-01-01

    RIASSUNTO. Scopo. Valutare in un campione di studenti universitari le differenze di genere nella frequenza di sintomi dello spettro d'ansia sociale. Materiali e metodi. Un campione di 823 studenti è stato valutato con il questionario per lo spettro d'ansia sociale nella versione autosomministrata (SHY-SR). Utilizzando il punteggio di 68 come valore ottimale di soglia diagnostica, il campione è stato classificato in due gruppi: un gruppo definito "low scorers" (<68 item) e uno definito "high scorers" (≥68 item). Risultati. Tra le femmine è stata evidenziata una percentuale significativamente superiore di "high scorers" rispetto ai maschi (32,5% vs 25,3%). Tra i 13 item risultati più frequenti (>60%), sono emerse delle differenze di genere significative per 6 item: le femmine presentavano una maggiore presenza di item relativi al "Timore di effettuare una performace", che sembrerebbe confermare il nuovo specificatore del DSM-5 per il disturbo d'ansia sociale detto "Performance-only", mentre i maschi presentavano una maggior frequenza in un unico item relativo all' "Inibizione Comportamentale". Nel sottogruppo di "low scorers" le femmine avevano ottenuto punteggi significativamente superiori sia nel totale che nei domini relativi ad "Ansie Specifiche e Sintomi Fobici" e alla "Sensitività Interpersonale" se confrontati con il gruppo dei maschi mentre nel sotto gruppo di "high scorers" i maschi presentavano punteggi significativamente superiori nei domini relativi a "Tratti social-fobici" durante l'infanzia e l'adolescenza" e a "Inibizione Comportamentale e Sintomi Somatici" rispetto al gruppo delle femmine. Infine, la percentuale di individui che hanno dichiarato di consumare alcol era significativamente superiore nei maschi rispetto alle femmine. Conclusioni. Nella categoria degli studenti universitari, lo spettro d'ansia sociale sembra essere più frequente nel genere femminile rispetto a quello maschile. Nei maschi, lo spettro d'ansia sociale è più frequentemente associato con un esordio precoce, inibizione comportamentale e sintomi somatici, e, di conseguenza, con una maggiore gravità. PMID:26780203

  11. GIL, a new c-di-GMP binding protein domain involved in regulation of cellulose synthesis in enterobacteria

    PubMed Central

    Fang, Xin; Ahmad, Irfan; Blanka, Andrea; Schottkowski, Marco; Cimdins, Annika; Galperin, Michael Y.; Römling, Ute; Gomelsky, Mark

    2014-01-01

    Summary In contrast to numerous enzymes involved in c-di-GMP synthesis and degradation in enterobacteria, only a handful of c-di-GMP receptors/effectors have been identified. In search of new c-di-GMP receptors, we screened the Escherichia coli ASKA overexpression gene library using the Differential Radial Capillary Action of Ligand Assay (DRaCALA) with fluorescently and radioisotope-labeled c-di-GMP. We uncovered three new candidate c-di-GMP receptors in E. coli and characterized one of them, BcsE. The bcsE gene is encoded in cellulose synthase operons in representatives of Gammaproteobacteria and Betaproteobacteria. The purified BcsE proteins from E. coli, Salmonella enterica and Klebsiella pneumoniae bind c-di-GMP via the domain of unknown function, DUF2819, which is hereby designated GIL, GGDEF I-site like domain. The RxGD motif of the GIL domain is required for c-di-GMP binding, similar to the c-di-GMP-binding I-site of the diguanylate cyclase GGDEF domain. Thus, GIL is the second protein domain, after PilZ, dedicated to c-di-GMP-binding. We show that in S. enterica, BcsE is not essential for cellulose synthesis but is required for maximal cellulose production, and that c-di-GMP binding is critical for BcsE function. It appears that cellulose production in enterobacteria is controlled by a two-tiered c-di-GMP-dependent system involving BcsE and the PilZ domain containing glycosyltransferase BcsA. PMID:24942809

  12. Correction to storm, Tressoldi, and di Risio (2010).

    PubMed

    2015-03-01

    Reports an error in "Meta-analysis of free-response studies, 1992-2008: Assessing the noise reduction model in parapsychology" by Lance Storm, Patrizio E. Tressoldi and Lorenzo Di Risio (Psychological Bulletin, 2010[Jul], Vol 136[4], 471-485). In the article, the sentence giving the formula in the second paragraph on p. 479 was stated incorrectly. The corrected sentence is included. (The following abstract of the original article appeared in record 2010-12718-001.) [Correction Notice: An erratum for this article was reported in Vol 136(5) of Psychological Bulletin (see record 2010-17510-009). In the article, the second to last sentence of the abstract (p. 471) was stated incorrectly. The sentence should read as follows: "The mean effect size value of the ganzfeld database was significantly higher than the mean effect size of the standard free-response database but was not higher than the effect size of the nonganzfeld noise reduction database."] We report the results of meta-analyses on 3 types of free-response study: (a) ganzfeld (a technique that enhances a communication anomaly referred to as "psi"); (b) nonganzfeld noise reduction using alleged psi-enhancing techniques such as dream psi, meditation, relaxation, or hypnosis; and (c) standard free response (nonganzfeld, no noise reduction). For the period 1997-2008, a homogeneous data set of 29 ganzfeld studies yielded a mean effect size of 0.142 (Stouffer Z = 5.48, p = 2.13 × 10-8). A homogeneous nonganzfeld noise reduction data set of 16 studies yielded a mean effect size of 0.110 (Stouffer Z = 3.35, p = 2.08 × 10-4), and a homogeneous data set of 14 standard free-response studies produced a weak negative mean effect size of -0.029 (Stouffer Z = -2.29, p = .989). The mean effect size value of the ganzfeld database were significantly higher than the mean effect size of the nonganzfeld noise reduction and the standard free-response databases. We also found that selected participants (believers in the paranormal, meditators, etc.) had a performance advantage over unselected participants, but only if they were in the ganzfeld condition. PMID:25730257

  13. diArk--the database for eukaryotic genome and transcriptome assemblies in 2014.

    PubMed

    Kollmar, Martin; Kollmar, Lotte; Hammesfahr, Björn; Simm, Dominic

    2015-01-01

    Eukaryotic genomes are the basis for understanding the complexity of life from populations to the molecular level. Recent technological innovations have revolutionized the speed of data generation enabling the sequencing of eukaryotic genomes and transcriptomes within days. The database diArk (http://www.diark.org) has been developed with the aim to provide access to all available assembled genomes and transcriptomes. In September 2014, diArk contains about 2600 eukaryotes with 6000 genome and transcriptome assemblies, of which 22% are not available via NCBI/ENA/DDBJ. Several indicators for the quality of the assemblies are provided to facilitate their comparison for selecting the most appropriate dataset for further studies. diArk has a user-friendly web interface with extensive options for filtering and browsing the sequenced eukaryotes. In this new version of the database we have also integrated species, for which transcriptome assemblies are available, and we provide more analyses of assemblies. PMID:25378341

  14. Supramolecular Hydrogels from Self-Assembly of di-Fmoc-L-lysine

    NASA Astrophysics Data System (ADS)

    Hashemnejad, Seyed Meysam; Naas, Kinsey; Kundu, Santanu

    Mechanical properties and nanostructure of a supramolecular hydrogel formed by self-assembly of di-fluorenylmethyloxycarbonyl-lysine (di-Fmoc-L-lysine) are reported here. Hydrogels were prepared by solvent switch technique in which water was added to a solution of di-Fmoc-L-lysine in dimethyl sulfoxide (DMSO). Mechanical properties of the gels were investigated using shear and cavitation rheology. The gels display strain-softening behavior at moderate strain values. Morphological investigations of the samples were conducted using FTIR and CD spectroscopy, electron microscopy, and atomic force microscopy (AFM). Self-assembled fibers with lateral dimensions ranging from 10 to 50 nm were captured in microscopy studies. FTIR results indicate β-sheet-like conformation of the peptides in the hydrogel.

  15. Cyclic (di)nucleotides: the common language shared by microbe and host.

    PubMed

    Gao, Juyi; Tao, Jianli; Liang, Weili; Jiang, Zhengfan

    2016-04-01

    Fluency in a common language allows individuals to convey information and carry out complex activities that otherwise would be difficult or even impossible without the benefit of shared communication. Cyclic (di)nucleotides have recently been recognized as such an accessible language understood by both microbe and the host, ever since remarkable progresses have revealed the molecular details of these nucleotide second messengers used in cellular communication systems. Though undergoing separate evolutionary pathways in prokaryotes and eukaryotes, cyclic (di)nucleotides enable microbes to influence host cells immediately and fiercely by modulating a variety of cellular activities. Here we highlight recent insights in cyclic (di)nucleotides and focus on the balancing of these indispensable signaling molecules by synthases and phosphodiesterases. PMID:26871480

  16. First results with Mercedes-Benz DI diesel engines running on monoesters of vegetable oils

    SciTech Connect

    Ventura, L.M.; Nascimento, A.C.; Bandel, W.

    1982-01-01

    In their pure form the vegetable oils are not suitable for the use in modern DI diesel engines, due to the excessive carbon deposit on the injection nozzles and in the combustion chamber. Nevertheless, these oils are promising candidates as raw materials for alternative diesel fuels. Processes are being developed to transform the long vegetable oil molecules into smaller molecules in order to fulfill the fuel requirements of DI diesel engines. Methyl and ethyl esters of fatty acids e.g. obtained by transesterification of vegetable oils through their catalytic reaction with methanol and ethanol, have shown a typical diesel fuel behaviour in conventional DI engines without excessive deposit formation. Problems concerning lubricating oil contamiation, and possibile remedial measures to avoid it, are being examined. There are also problems to be solved in relation to white smoke formation and the odor of exhaust gases. 10 figures.

  17. c-di-GMP signalling and the regulation of developmental transitions in streptomycetes.

    PubMed

    Bush, Matthew J; Tschowri, Natalia; Schlimpert, Susan; Flärdh, Klas; Buttner, Mark J

    2015-12-01

    The complex life cycle of streptomycetes involves two distinct filamentous cell forms: the growing (or vegetative) hyphae and the reproductive (or aerial) hyphae, which differentiate into long chains of spores. Until recently, little was known about the signalling pathways that regulate the developmental transitions leading to sporulation. In this Review, we discuss important new insights into these pathways that have led to the emergence of a coherent regulatory network, focusing on the erection of aerial hyphae and the synchronous cell division event that produces dozens of unigenomic spores. In particular, we highlight the role of cyclic di-GMP (c-di-GMP) in controlling the initiation of development, and the role of the master regulator BldD in mediating c-di-GMP signalling. PMID:26499894

  18. diArk – the database for eukaryotic genome and transcriptome assemblies in 2014

    PubMed Central

    Kollmar, Martin; Kollmar, Lotte; Hammesfahr, Björn; Simm, Dominic

    2015-01-01

    Eukaryotic genomes are the basis for understanding the complexity of life from populations to the molecular level. Recent technological innovations have revolutionized the speed of data generation enabling the sequencing of eukaryotic genomes and transcriptomes within days. The database diArk (http://www.diark.org) has been developed with the aim to provide access to all available assembled genomes and transcriptomes. In September 2014, diArk contains about 2600 eukaryotes with 6000 genome and transcriptome assemblies, of which 22% are not available via NCBI/ENA/DDBJ. Several indicators for the quality of the assemblies are provided to facilitate their comparison for selecting the most appropriate dataset for further studies. diArk has a user-friendly web interface with extensive options for filtering and browsing the sequenced eukaryotes. In this new version of the database we have also integrated species, for which transcriptome assemblies are available, and we provide more analyses of assemblies. PMID:25378341

  19. Synthesis and characterization of ?-cyclodextrin inclusion complex containing di(8-hydroxyquinoline)magnesium

    NASA Astrophysics Data System (ADS)

    He, Jiang; Deng, Li; Yang, Shanshan

    2008-09-01

    The ?-cyclodextrin (?-CD) inclusion complex containing di(8-hydroxyquinoline)magnesium was prepared. The product was characterized by NMR, IR, differential thermal thermogravimetric analysis (DT-TGA), spectrofluorimetry, and elemental analysis, indicating the formation of inclusion complex in which the quinoline rings of the guest were encapsulated within the ?-CD cavities. The Job's method provided 2:1 stoichiometry for the inclusion complex between ?-CD and di(8-hydroxyquinoline)magnesium. The association constant calculated with the modified Benesi-Hildebrand equation at 25 C was determined. And the mean association constant was 3577 (L/mol) 2, R.S.D. was 2.58%. The thermal stability and solubility of di(8-hydroxyquinoline)magnesium were improved when forming inclusion complex.

  20. Propulsion Diagnostic Method Evaluation Strategy (ProDiMES) User's Guide

    NASA Technical Reports Server (NTRS)

    Simon, Donald L.

    2010-01-01

    This report is a User's Guide for the Propulsion Diagnostic Method Evaluation Strategy (ProDiMES). ProDiMES is a standard benchmarking problem and a set of evaluation metrics to enable the comparison of candidate aircraft engine gas path diagnostic methods. This Matlab (The Mathworks, Inc.) based software tool enables users to independently develop and evaluate diagnostic methods. Additionally, a set of blind test case data is also distributed as part of the software. This will enable the side-by-side comparison of diagnostic approaches developed by multiple users. The Users Guide describes the various components of ProDiMES, and provides instructions for the installation and operation of the tool.

  1. Hooked on the nicotine addiction thesis: a response to DiFranza.

    PubMed

    Dar, Reuven; Frenk, Hanan

    2013-01-01

    DiFranza's rebuttal to our critique of the "Hooked on Nicotine" research program misconstrues our arguments beyond recognition. The grossest misrepresentation of our critique by DiFranza is that we devise (by thwarting science) to rescue "the conventional wisdom" of the "threshold model of nicotine addiction." In fact, the difference between our positions lies elsewhere: We believe that nicotine is not an addictive drug and that its contribution to the smoking habit is secondary; DiFranza believes that nicotine is so powerfully addictive that novice smokers can lose autonomy over their smoking behavior after one cigarette or even following a single puff. Our review aimed to critically examine the empirical basis of this extreme version of the nicotine "addiction" model. In this brief commentary we illustrate how the commitment to the nicotine "addiction" theory has biased the methodology and the interpretation of the data in "Hooked on Nicotine" research program. PMID:24246023

  2. The First Case Report in Italy of Di George Syndrome Detected by Noninvasive Prenatal Testing

    PubMed Central

    Rapacchia, Giuseppina; Lapucci, Cristina; Pittalis, Maria Carla; Youssef, Aly; Farina, Antonio

    2015-01-01

    Panorama Plus (Natera), a single-nucleotide polymorphism- (SNP-) based approach that relies on the identification of maternal and fetal allele distributions, allows the detection of common aneuploidies and also incorporates a panel of 5 microdeletions including Di George syndrome. We report here the first case of Di George syndrome detected by NIPT in Italy; blood was drawn at 12 weeks' gestation. The patient had an amniocentesis to confirm the diagnosis by MLPA (multiplex ligation-dependent probe amplification) and an ultrasound aimed to detect the features associated with the syndrome. A right aortic arch and suspect of thymus atrophy were detected, but not other severe malformations typical of the disease. The patient terminated the pregnancy at 17 weeks. NIPT allowed an early screening of Di George syndrome. As the patient was at low risk, it is likely that an ultrasound would have missed the condition. PMID:26346617

  3. Aqueous phase oxidation of methane with hydrogen peroxide catalyzed by di-iron-substituted silicotungstate

    SciTech Connect

    Mizuno, Noritaka; Seki, Yasuhiro; Nishiyama, Yoshiyuki; Kiyoto, Ikuro; Misono, Makoto

    1999-06-10

    The active site of methane monooxygenase has been shown to have a {mu}-hydroxo di-iron structure. Among alkanes, the activation and functionalization of methane have attracted much attention because of its abundance and low reactivity. Recently, there has been a renewed interest in the direct conversion of methane into oxygenates with environmentally clean oxidants such as molecular oxygen and hydrogen peroxide. The use of water as a solvent in homogeneous transition-metal catalysis has been of growing importance because of its environmentally friendly nature. In these aspects, catalytic oxygenation of methane with hydrogen peroxide in water by model complex catalysts with di-iron centers is of great interest but has been unsuccessful due to the catalyst instability (particularly organic ligands) towards hydrogen peroxide and insolubility in water. In this paper, the authors attempt to demonstrate catalytic oxidation of methane with hydrogen peroxide in water by di-iron-substituted silicotungstate.

  4. c-di-AMP Secreted by Intracellular Listeria monocytogenes Activates a Host Type I Interferon Response

    PubMed Central

    Woodward, Joshua J.; Iavarone, Anthony T.; Portnoy, Daniel A.

    2011-01-01

    Intracellular bacterial pathogens, such as Listeria monocytogenes, are detected in the cytosol of host immune cells. Induction of this host response is often dependent on microbial secretion systems, and in L. monocytogenes, is dependent on multi-drug efflux pumps (MDRs). Using L. monocytogenes mutants that over-expressed MDRs, we identified cyclic diadenosine monophosphate (c-di-AMP) as a secreted molecule able to trigger the cytosolic host response. Over-expression of the di-adenylate cyclase, dacA (lmo2120), resulted in elevated levels of the host response during infection. C-di-AMP thus represents a putative bacterial secondary signaling molecule that triggers a cytosolic pathway of innate immunity and is predicted to be present in a wide variety of bacteria and archea. PMID:20508090

  5. Synthesis, conformational and theoretical studies of 1,n-di(2-formyl-4-phenylazophenoxy)alkanes

    NASA Astrophysics Data System (ADS)

    Balachander, R.; Manimekalai, A.

    2016-01-01

    1,n-di(2-Formyl-4-phenylazophenoxy)alkanes 1 and 2 and 1,3-di(2-formyl-4-phenylazophenoxymethyl)benzene 3 were synthesis and characterized by FT-IR, UV-Vis, 1H, 13C NMR and mass spectral studies. The stable conformations of 1-3 were predicted theoretically and selected geometrical parameters were derived from optimized structures. The molecular parameters of HOMO-LUMO energies, polarizability, hyperpolarizability, natural bond orbital (NBO), atom in molecule (AIM) analysis and molecular electrostatic potential (MEP) surfaces were determined by the density functional theory (DFT) method and analysed.

  6. A separation and purification procedure for [14C] di-2-ethylhexyl phthalate in fish.

    PubMed

    Karara, A H; Hayton, W L; Archer, B G

    1984-01-01

    A procedure utilizing the reverse isotope dilution analysis is presented for the determination of di-2-ethylhexyl phthalate (DEHP) and total metabolites in tissues of fish and water samples. This procedure offers several advantages: it eliminates laborious and expensive use of column chromatography and identification by gas chromatography/mass spectrometry analysis; it does not require quantitative separation; it selectively removes fish lipids by partitioning across a hexane/acetonitrile system; it uses an internal standard, di-pentylphthalate, for the gas-liquid chromatographic analysis; and it overcomes interference from background DEHP. PMID:6738003

  7. Pyridine derivatives, especially 2,6-di-tert-butylpyridine, labeled with nitrogen-15.

    PubMed

    Fărcaşiu, Dan; Lezcano, Marta

    2013-10-01

    Pyridine derivatives labeled with (15) N can be prepared by the reaction of the corresponding pyrylium salts with (15) NH4 Cl in close to a stoichiometric ratio, in a sodium acetate-acetic acid buffer. In particular, the reaction of 2,6-di-tert-butylpyrylium perchlorate gave 2,6-di-tert-butylpyridine with a conversion of 95%. The compound is valuable for studies of acid-base interactions on solid acid catalysts by (15) N nuclear magnetic resonance. PMID:24285241

  8. Visible Light-Promoted Decarboxylative Di- and Trifluoromethylthiolation of Alkyl Carboxylic Acids.

    PubMed

    Candish, Lisa; Pitzer, Lena; Gómez-Suárez, Adrián; Glorius, Frank

    2016-03-24

    Described herein is a new and straightforward decarboxylative di- and trifluoromethylthiolation of alkyl carboxylic acids promoted by visible light. This approach enables the synthesis of biologically relevant alkyl SCF2 H and SCF3 compounds from cheap and abundant carboxylic acids. The method is operationally simple, using irradiation from household light sources, and its mild reaction conditions make it tolerant of a range of functional groups. The strategy employs electrophilic phthalimide-derived di- and trifluoromethylthiolation reagents and exploits the ability of the imidyl radical to carry a radical chain. PMID:26840376

  9. Studying 750 GeV di-photon resonance at photon-photon collider

    NASA Astrophysics Data System (ADS)

    Ito, Hayato; Moroi, Takeo; Takaesu, Yoshitaro

    2016-05-01

    Motivated by the recent LHC discovery of the di-photon excess at the invariant mass of ∼ 750 GeV, we study the prospect of investigating the scalar resonance at a future photon-photon collider. We show that, if the di-photon excess observed at the LHC is due to a new scalar boson coupled to the standard-model gauge bosons, such a scalar boson can be observed and studied at the photon-photon collider with the center-of-mass energy of ∼ 1 TeV in large fraction of parameter space.

  10. MedSynDiKATe--design considerations for an ontology-based medical text understanding system.

    PubMed Central

    Hahn, U.; Romacker, M.; Schulz, S.

    2000-01-01

    MedSynDiKATe is a natural language processor for automatically acquiring knowledge from medical finding reports. The content of these documents is transferred to formal representation structures which constitute a corresponding text knowledge base. The general system architecture we present integrates requirements from the analysis of single sentences, as well as those of referentially linked sentences forming cohesive texts. The strong demands MedSynDiKATe poses to the availability of expressive knowledge sources are accounted for by two alternative approaches to (semi)automatic ontology engineering. PMID:11079899

  11. (Di­methyl­phosphor­yl)methanaminium iodide–(di­methyl­phosphor­yl)methan­amine (1/1)

    PubMed Central

    Reiss, Guido J.

    2013-01-01

    The asymmetric unit of the title structure, C3H11NOP+·I−·C3H10NOP, consists of one (di­methyl­phosphor­yl)methanamine (dpma) mol­ecule, one (di­methyl­phosphor­yl)methanaminium (dpmaH) ion and one iodide counter-anion. In the crystal, medium–strong to weak N—H⋯O and N—H⋯N hydrogen bonds connect dpmaH cations and dpma mol­ecules into strands along [001]. The iodide counter-anions form only very weak hydrogen bonds. The crystal used for the diffraction study was found to be an inversion twin with a ratio of 0.83 (2):0.17 (2). The title structure is isotypic to that of dpmaH[ClO4]·dpma [Buhl et al. (2013 ▶). Crystals 3, 350–362]. PMID:24109340

  12. Crystal structure of tris­(di­methyl­amido-κN)­bis­(di­methyl­amine-κN)­zirconium(IV) iodide

    PubMed Central

    Clark, Wesley D.; Akurathi, Gopalakrishna; Valle, Henry U.; Hollis, T. Keith

    2016-01-01

    Zirconium amides have become increasingly popular and useful due to their widespread use as precursors to other zirconium complexes and their use in the production of solid oxide fuel cells (SOFCs). Herein we report the mol­ecular structure of tris­(di­methyl­amido)­bis­(di­methyl­amine)­zirconium(IV) iodide, [Zr(C2H6N)3(C2H7N)2]I. The bond lengths and bond angles are consistent with a slightly distorted trigonal–bipyramidal coordination geometry around the metal atom. N⋯I contacts of 3.6153 (15) and 3.5922 (14) Å are consistent with the presence of N—H⋯I inter­actions. These N—H⋯I inter­actions link the complex cations and iodide anions into extended chains that propagate parallel to the a axis. PMID:26870590

  13. 4-(Di­methyl­amino)­pyridinium trichlorido[4-(di­methyl­amino)­pyridine-κN]cobaltate(II)

    PubMed Central

    Guenifa, Fatiha; Hadjadj, Nasreddine; Zeghouan, Ouahida; Bendjeddou, Lamia; Merazig, Hocine

    2013-01-01

    In the anion of the title compound, (C7H11N2)[CoCl3(C7H10N2)], the CoII ion is coordinated by one N atom from a 4-(di­methyl­amino)­pyridine (DMAP) ligand and three Cl atoms, forming a CoNCl3 polyhedron with a distorted tetra­hedral geometry. In the crystal, cations and anions are linked via weak N—H⋯Cl and C—H⋯Cl hydrogen bonds. Double layers of complex anions stack along the b- axis direction, which alternate with double layers of 4-(di­methyl­amino)-pyridinium cations. PMID:24046560

  14. PERIPUBERTAL DI (2-ETHYLHEXYL) PHTHALATE EXPOSURE INHIBITS ANDROGEN SENSITIVE TISSUE DEVELOPMENT AND DELAYS PUBERTY IN MALE SPRAGUE-DAWLEY RATS

    EPA Science Inventory

    PERIPUBERTAL DI (2-ETHYLHEXYL) PHTHALATE EXPOSURE INHIBITS ANDROGEN SENSITIVE TISSUE DEVELOPMENT AND DELAYS PUBERTY IN MALE SPRAGUE-DAWLEY RATS

    Nigel Noriega, Jonathan Furr, Christy Lambright, Vickie Wilson, L. Earl Gray Jr.

    The plasticizer Di (2-ethylhexyl) phtha...

  15. 32 CFR 644.336 - Notices to Departments of Interior (DI); Health and Human Resources (HHR); Education; and Housing...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 32 National Defense 4 2010-07-01 2010-07-01 true Notices to Departments of Interior (DI); Health and Human Resources (HHR); Education; and Housing and Urban Development (HUD). 644.336 Section 644.336... Departments of Interior (DI); Health and Human Resources (HHR); Education; and Housing and Urban...

  16. 32 CFR 644.336 - Notices to Departments of Interior (DI); Health and Human Resources (HHR); Education; and Housing...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 32 National Defense 4 2011-07-01 2011-07-01 false Notices to Departments of Interior (DI); Health and Human Resources (HHR); Education; and Housing and Urban Development (HUD). 644.336 Section 644.336... Departments of Interior (DI); Health and Human Resources (HHR); Education; and Housing and Urban...

  17. 76 FR 51980 - Atlantic Shipping Company, Inc. v. Di Nos Shipping, Inc.; Notice of Filing of Complaint and...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-08-19

    ... COMMISSION Atlantic Shipping Company, Inc. v. Di Nos Shipping, Inc.; Notice of Filing of Complaint and...) by Atlantic Shipping Company, Inc., hereinafter ``Complainant,'' against DI Nos Shipping, Inc... Respondent is in violation of the Shipping Act of 1984, 46 U.S.C. 40901 and 40902, by operating as a...

  18. Migration matrices and surnames in populations with different isolation patterns: Val di Lima (Italian Apennines), Val di Sole (Italian Alps), and La Cabrera (Spain).

    PubMed

    Boattini, Alessio; Calboli, Federico C F; Blanco Villegas, Maria José; Gueresi, Paola; Franceschi, Marcello G; Paoli, Giorgio; Cavicchi, Sandro; Pettener, Davide

    2006-01-01

    Biodemographic methods are widely used to infer the genetic structure of human populations. In this study, we revise and standardize the procedures required by the migration matrix model of Malécot ([1950] Ann Univ Lyon Sci [A] 13:37-60), testing it in large historical-demographic databases of 85 populations from three mountain valleys with different degrees of isolation: Val di Lima (Italian Apennines, 21 parishes), Val di Sole, (Italian Alps, 27 parishes), and La Cabrera (Spain, 37 parishes). An add-on package (Biodem) for the R program is proposed to perform all calculations. Results from migration matrices are compared with those obtained from isonymic relationships. Migration and isonymy matrices are derived from 22,781 marriage records. Matrices are analyzed using a nonlinear isolation-by-distance (IBD) model and multivariate techniques (multidimensional scaling, Procrustes rotation, and cluster analysis). Microdifferentiation levels (F(ST)) from the migration data agree with the observed inbreeding values: higher values are found in La Cabrera (F(ST) = 0.0082), the most isolated population; Val di Lima (F(ST) = 0.0015) and Val di Sole (F(ST) = 0.0012) have lower values due to the larger parish population sizes and greater mobility. Temporal changes of F(ST) and IBD are analyzed using the migration matrix approach. The populations show a marked decline in F(ST) values in time, together with increased population mobility and emigration rates. In all three valleys, marital migration and isonymy yield similar results, suggesting that geographic distance is the most important factor structuring the populations. However, isonymy shows a lower correlation with geographic distance than migration matrices do. This difference can be attributed to the differing sensitivity of the methods for past migration events, and to genetic drift. PMID:16917890

  19. Fourier-transform infrared and Raman spectra, and ab initio calculations for cadmium-n-di-iso-propylphosphorylguanidine-di-chloride (CdDPGCl2) complex.

    PubMed

    Téllez, Claudio A; Hollauer, Eduardo; Felcman, Judith; Lopes, Damiana C N; Cattapan, Renata A

    2002-07-01

    Cadmium-n-di-isopropylphosphorylguanidine-di-chloride (CdDPGCl2) was synthesized in the solid phase and characterized previously. The Fourier transform infrared and Raman spectra of (CdDPGCl2) in the solid state were recorded and analyzed. Emphasis was placed on the vibrational assignment of the [(O2P=O-[CdCl2]-HN=C) fragment of the complete molecular structure. With the aim of assisting the vibrational assignment of the experimental spectra, a comparison with the spectra of N-di-isopropylphosphorylguanidine ligand was carried out and ab initio calculations have been performed with several effective core potentials and valence basis sets (Hay-Wadt (HW) and Stevens-Basch-Krauss (SBK)). Due to our limited computational resources, hydrogen atoms replaced the isopropyl groups. The calculated geometrical parameters showed excellent agreement with the experimental, as well as the RHF/MP2 calculated infrared wave numbers, when compared to the IR/Raman experimental wave numbers. PMID:12164485

  20. Utility of the 3Di Short Version for the Diagnostic Assessment of Autism Spectrum Disorder and Compatibility with DSM-5.

    PubMed

    Slappendel, Geerte; Mandy, William; van der Ende, Jan; Verhulst, Frank C; van der Sijde, Ad; Duvekot, Jorieke; Skuse, David; Greaves-Lord, Kirstin

    2016-05-01

    The Developmental Diagnostic Dimensional Interview-short version (3Di-sv) provides a brief standardized parental interview for diagnosing autism spectrum disorder (ASD). This study explored its validity, and compatibility with DSM-5 ASD. 3Di-sv classifications showed good sensitivity but low specificity when compared to ADOS-2-confirmed clinical diagnosis. Confirmatory factor analyses found a better fit against a DSM-5 model than a DSM-IV-TR model of ASD. Exploration of the content validity of the 3Di-sv for the DSM-5 revealed some construct underrepresentation, therefore we obtained data from a panel of 3Di-trained clinicians from ASD-specialized centers to recommend items to fill these gaps. Taken together, the 3Di-sv provides a solid basis to create a similar instrument suitable for DSM-5. Concrete recommendations are provided to improve DSM-5 compatibility. PMID:26825661

  1. Regulation of biofilm formation and cellular buoyancy through modulating intracellular cyclic di-GMP levels in engineered cyanobacteria.

    PubMed

    Agostoni, Marco; Waters, Christopher M; Montgomery, Beronda L

    2016-02-01

    The second messenger cyclic dimeric (3'→5') GMP (cyclic di-GMP or c-di-GMP) has been implicated in the transition between motile and sessile lifestyles in bacteria. In this study, we demonstrate that biofilm formation, cellular aggregation or flocculation, and cellular buoyancy are under the control of c-di-GMP in Synechocystis sp. PCC 6803 (Synechocystis) and Fremyella diplosiphon. Synechocystis is a unicellular cyanobacterium and displays lower levels of c-di-GMP; F. diplosiphon is filamentous and displays higher intracellular c-di-GMP levels. We transformed Synechocystis and F. diplosiphon with a plasmid for constitutive expression of genes encoding diguanylate cylase (DGC) and phosphodiesterase (PDE) proteins from Vibrio cholerae or Escherichia coli, respectively. These engineered strains allowed us to modulate intracellular c-di-GMP levels. Biofilm formation and cellular deposition were induced in the DGC-expressing Synechocystis strain which exhibited high intracellular levels of c-di-GMP; whereas strains expressing PDE in Synechocystis and F. diplosiphon to drive low intracellular levels of c-di-GMP exhibited enhanced cellular buoyancy. In addition, the PDE-expressing F. diplosiphon strain showed elevated chlorophyll levels. These results imply roles for coordinating c-di-GMP homeostasis in regulating native cyanobacterial phenotypes. Engineering exogenous DGC or PDE proteins to regulate intracellular c-di-GMP levels represents an effective tool for uncovering cryptic phenotypes or modulating phenotypes in cyanobacteria for practical applications in biotechnology applicable in photobioreactors and in green biotechnologies, such as energy-efficient harvesting of cellular biomass or the treatment of metal-containing wastewaters. Biotechnol. Bioeng. 2016;113: 311-319. © 2015 Wiley Periodicals, Inc. PMID:26192200

  2. Systematic analysis of cyclic di-GMP signaling enzymes and their role in biofilm formation and virulence in Yersinia pestis

    PubMed Central

    Bobrov, Alexander G.; Kirillina, Olga; Ryjenkov, Dmitri A.; Waters, Christopher M.; Price, Paul A.; Fetherston, Jacqueline D.; Mack, Dietrich; Goldman, William E.; Gomelsky, Mark; Perry, Robert D.

    2011-01-01

    Cyclic di-GMP (c-di-GMP) is a signaling molecule that governs the transition between planktonic and biofilm states. Previously we showed that the diguanylate cyclase HmsT and the putative c-di-GMP phosphodiesterase HmsP inversely regulate biofilm formation through control of HmsHFRS-dependent poly-?-1,6-N-acetylglucosamine synthesis. Here, we systematically examine the functionality of the genes encoding putative c-di-GMP metabolic enzymes in Yersinia pestis. We determine that, in addition to hmsT and hmsP, only the gene y3730 encodes a functional enzyme capable of synthesizing c-di-GMP. The seven remaining genes are pseudogenes or encode proteins that do not function catalytically or are not expressed. Furthermore, we show that HmsP has c-di-GMP-specific phosphodiesterase activity. We report that a mutant incapable of c-di-GMP synthesis is unaffected in virulence in plague mouse models. Conversely, an hmsP mutant, unable to degrade c-di-GMP, is defective in virulence by a subcutaneous route of infection due to poly-?-1,6-N-acetylglucosamine overproduction. This suggests that c-di-GMP signaling is not only dispensable but deleterious for Y. pestis virulence. Our results show that a key event in the evolution of Y. pestis from the ancestral Yersinia pseudotuberculosis was a significant reduction in the complexity of its c-di-GMP signaling network likely resulting from the different disease cycles of these human pathogens. PMID:21219468

  3. Active coating to prolong the shelf life of Fior di latte cheese.

    PubMed

    Alessandro Del Nobile, Matteo; Gammariello, Daniela; Di Giulio, Stefania; Conte, Amalia

    2010-02-01

    This study explains how active coating can serve to prolong the shelf life of Fior di latte cheese. The active coating was prepared by dissolving, in two sodium alginic acid solutions (5 and 8% w/v), different concentrations of lysozyme (0.25, 0.50 and 1.00 mg ml-1)+50 mm of Ethylene-Diamine Tetraacetic Acid (EDTA). Samples of Fior di latte cheese packaged in brine and active brine (lysozyme+EDTA, at the above concentrations) were also used as controls. The quality decay of the Fior di latte cheese stored at 10 degrees C was assessed by monitoring the viable cell concentration of the main spoilage microorganism, as well as its sensory quality (i.e., external appearance, consistency, colour and flavour). The concentration of rod-or coccus-shaped Lactic Acid Bacteria (LAB) was also monitored to assess the effect of the proposed packaging strategies on the flora type of Fior di latte cheese. The results show that an increase in the shelf life equal to 104% was recorded for the coated samples, compared with controls packaged in brine without active compounds. This shelf life increase is slightly lower than that recorded with samples packaged in the active brine (151%), as a result of a more pronounced microbial proliferation; however, the coating could be a better packaging solution for the reduced weight of tray. PMID:19889250

  4. Di(phenylpropylamino)gossypol: a derivative of the dimeric natural product gossypol

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Di(phenylpropylamino)gossypol [2,2'-bis(1,6-dihydroxy,-5-isopropyl,-8-methineaminopropylbenzene-3-methyl)-naphthylene-7-one, C48H52N2O6] is formed by reaction of the dimeric natural product gossypol with 3-phenyl-1-propylamine. When crystallized from diethyl ether, the compound has monoclinic (P21/c...

  5. The Theory behind the Theory in DCT and SCDT: A Response to Rigazio-DiGilio.

    ERIC Educational Resources Information Center

    Terry, Linda L.

    1994-01-01

    Responds to previous article by Rigazio-DiGilio on Developmental Counseling and Therapy and Systemic Cognitive-Developmental Therapy as two integrative models that unify individual, family, and network treatment within coconstructive-developmental framework. Discusses hidden complexities in cognitive-developmental ecosystemic integration and…

  6. Draft Genome Sequence of the Xylella fastidiosa CoDiRO Strain.

    PubMed

    Giampetruzzi, Annalisa; Chiumenti, Michela; Saponari, Maria; Donvito, Giacinto; Italiano, Alessandro; Loconsole, Giuliana; Boscia, Donato; Cariddi, Corrado; Martelli, Giovanni Paolo; Saldarelli, Pasquale

    2015-01-01

    We determined the draft genome sequence of the Xylella fastidiosa CoDiRO strain, which has been isolated from olive plants in southern Italy (Apulia). It is associated with olive quick decline syndrome (OQDS) and characterized by extensive scorching and desiccation of leaves and twigs. PMID:25676759

  7. Dose Reconstruction of Di-2-Ethylhexyl Phthalate Using a Simple Pharmacokinetic Model [Manuscript

    EPA Science Inventory

    Background In 2005, eight adults provided full volumes and times of urine voids during one normal work week. These samples were analyzed for four di-2-ethylhexyl phthalate (DEHP) metabolites. Participants also provided diary information on their diet, driving, and outdoor a...

  8. Draft Genome Sequence of the Xylella fastidiosa CoDiRO Strain

    PubMed Central

    Chiumenti, Michela; Saponari, Maria; Donvito, Giacinto; Italiano, Alessandro; Loconsole, Giuliana; Boscia, Donato; Cariddi, Corrado; Martelli, Giovanni Paolo; Saldarelli, Pasquale

    2015-01-01

    We determined the draft genome sequence of the Xylella fastidiosa CoDiRO strain, which has been isolated from olive plants in southern Italy (Apulia). It is associated with olive quick decline syndrome (OQDS) and characterized by extensive scorching and desiccation of leaves and twigs. PMID:25676759

  9. Di-tert-butylsilylene-directed alpha-selective synthesis of 4-methylumbelliferyl T-antigen.

    PubMed

    Imamura, Akihiro; Ando, Hiromune; Ishida, Hideharu; Kiso, Makoto

    2005-09-29

    [reaction: see text] We have succeeded in the facile synthesis of 4-methylumbelliferyl T-antigen as a substrate for endo-alpha-N-acetylgalactosaminidase by exploiting the combination of the di-tert-butylsilylene effect and the Mitsunobu reaction. PMID:16178547

  10. Yield and economics of shallow subsurface drip irrigation (S3DI) and furrow diking

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A shallow subsurface drip irrigation (S3DI) was installed yearly in conjunction with furrow diking to document yield and economic benefit of these techniques on peanut (Arachis hypogaea L.), cotton (Gossypium hirsutum L.), and corn (Zea mays L.). This research was conducted for three years from 2005...

  11. Three new di-O-glycosyl-C-glucosyl flavones from the leaves of Caesalpinia ferrea Mart..

    PubMed

    Nawwar, Mahmoud; El-Mousallami, Amani; Hussein, Sahar; Hashem, Amani; Mousa, Mona; Lindequist, Ulrike; Linscheid, Michael

    2014-01-01

    Three hitherto unknown di-O-xylosyl-C-glycosyl flavones were isolated from the leaves of Caesalpinia ferrea. The structures of all isolated compounds were elucidated by conventional methods and spectroscopic analysis, including 1D and 2D NMR, as well as by HRESIMS. PMID:25711035

  12. MODULATION OF RAT LEYDIG CELL STEROIDOGENIC FUNCTION BY DI(2-ETHYLHEXYL)PHTHALATE

    EPA Science Inventory

    Modulation of rat Leydig cell steroidogenic function by di(2-ethylhexyl)phthalate.

    Akingbemi BT, Youker RT, Sottas CM, Ge R, Katz E, Klinefelter GR, Zirkin BR, Hardy MP.

    Center for Biomedical Research, Population Council, New York, New York 10021, USA. benson@popcbr...

  13. Circuits for grasping: spinal dI3 interneurons mediate cutaneous control of motor behavior

    PubMed Central

    Bui, Tuan V.; Akay, Turgay; Loubani, Osama; Hnasko, Thomas S.; Jessell, Thomas M.; Brownstone, Robert M.

    2013-01-01

    SUMMARY Accurate motor performance depends on the integration in spinal microcircuits of sensory feedback information. Hand grasp is a skilled motor behavior known to require cutaneous sensory feedback, but spinal microcircuits that process and relay this feedback to the motor system have not been defined. We sought to define classes of spinal interneurons involved in the cutaneous control of hand grasp in mice, and show that dI3 interneurons, a class of dorsal spinal interneurons marked by expression of Isl1, convey input from low threshold cutaneous afferents to motoneurons. Mice in which the output of dI3 interneurons has been inactivated exhibit deficits in motor tasks that rely on cutaneous afferent input. Most strikingly, the ability to maintain grip strength in response to increasing load is lost following genetic silencing of dI3 interneuron output. Thus, spinal microcircuits that integrate cutaneous feedback crucial for paw grip rely on the intermediary role of dI3 interneurons. PMID:23583114

  14. MECHANISTIC CONSIDERATIONS FOR HUMAN RELEVANCE OF CANCER HAZARD OF DI(2-ETHYLHEXYL) PHTHALATE

    EPA Science Inventory

    Di(2-ethylhexyl) phthalate (DEHP) is a peroxisome proliferator agent that is widely used as a plasticizer to soften polyvinylchloride plastics and non-polymers. Both occupational (e.g., by inhalation during its manufacture and use as a plasticizer of polyvinylchloride) and enviro...

  15. Shallow subsurface drip irrigation (S3DI) for small irregular-shaped fields in the southeast

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Field tests were conducted using S3DI on cotton (Gossypium hirsutum, L.), corn (Zea mays, L.), and peanut (Arachis hypogeae, L.) rotations to investigate yield potential and economic sustainability of this irrigation system. Drip tubing was installed in alternate row middles, strip tillage was used ...

  16. D.O.P. and D.I. secured room (room 215), looking west towards ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    D.O.P. and D.I. secured room (room 215), looking west towards murals. Sliding map tracks are visible on the floor next to the wall at left. Also note original fluorescent lights - March Air Force Base, Strategic Air Command, Combat Operations Center, 5220 Riverside Drive, Moreno Valley, Riverside County, CA

  17. Circuits for grasping: spinal dI3 interneurons mediate cutaneous control of motor behavior.

    PubMed

    Bui, Tuan V; Akay, Turgay; Loubani, Osama; Hnasko, Thomas S; Jessell, Thomas M; Brownstone, Robert M

    2013-04-10

    Accurate motor performance depends on the integration in spinal microcircuits of sensory feedback information. Hand grasp is a skilled motor behavior known to require cutaneous sensory feedback, but spinal microcircuits that process and relay this feedback to the motor system have not been defined. We sought to define classes of spinal interneurons involved in the cutaneous control of hand grasp in mice and to show that dI3 interneurons, a class of dorsal spinal interneurons marked by the expression of Isl1, convey input from low threshold cutaneous afferents to motoneurons. Mice in which the output of dI3 interneurons has been inactivated exhibit deficits in motor tasks that rely on cutaneous afferent input. Most strikingly, the ability to maintain grip strength in response to increasing load is lost following genetic silencing of dI3 interneuron output. Thus, spinal microcircuits that integrate cutaneous feedback crucial for paw grip rely on the intermediary role of dI3 interneurons. PMID:23583114

  18. Genetic Modifiers of the Physical Malformations in Velo-Cardio-Facial Syndrome/DiGeorge Syndrome

    ERIC Educational Resources Information Center

    Aggarwal, Vimla S.; Morrow, Bernice E.

    2008-01-01

    Velo-cardio-facial syndrome/DiGeorge syndrome (VCFS/DGS), the most common micro-deletion disorder in humans, is characterized by craniofacial, parathyroid, and thymic defects as well as cardiac outflow tract malformations. Most patients have a similar hemizygous 3 million base pair deletion on 22q11.2. Studies in mouse have shown that "Tbx1", a

  19. DEVELOPMENTAL EXPOSURE TO DI-N-BUTYLTIN DICHLORIDE (DBTC): IMMUNOTOXIC AND NEUROTOXIC EVALUATION

    EPA Science Inventory

    Organotins are incorporated as stabilizers in PVC water supply pipe. Particularly when new, mono- and di-substituted methyl- and butyltins leach from the pipe and are thus of regulatory concern to EPA. These contaminants have adverse effects on both the immune and nervous systems...

  20. VITELLOGENIN GENE EXPRESSION IN MALE FATHEAD MINNOWS EXPOSED TO DI(2-ETHYLHEXYL)PHTHALATE

    EPA Science Inventory

    Di(2-ethylhexyl) phthalate (DEHP) is a plasticizer used extensively in the plastics industry. DEHP has been shown to be ubiquitous in the environment and has been detected in ground and surface waters, sediment sludge and at several Superfund sites. Previous studies using rats ...

  1. MALDI-TOF Mass Spectrometry of Naturally-Occurring Mixtures of Mono- and Di-rhamnolipids

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) has been developed for high-throughput screening of naturally-occurring mixtures of rhamnolipids from Pseudomonas spp. Mono- and di-rhamnolipids are readily distinguished by characteristic molecular adduct i...

  2. The Instructional Instrument SL-EDGE Student Library-Educational DiGital Environment.

    ERIC Educational Resources Information Center

    Kyriakopoulou, Antonia; Kalamboukis, Theodore

    An educational digital environment that will provide appropriate methods and techniques for the support and enhancement of the educational and learning process is a valuable tool for both educators and learners. In the context of such a mission, the educational tool SL-EDGE (Student Library-Educational DiGital Environment) has been developed. The…

  3. Endoplasmic reticulum stress as a novel cellular response to di (2-ethylhexyl) phthalate exposure.

    PubMed

    Peropadre, Ana; Fernández Freire, Paloma; Pérez Martín, José Manuel; Herrero, Óscar; Hazen, María José

    2015-12-25

    Di (2-ethylhexyl) phthalate is a high-production chemical widely used as a plasticizer for polyvinyl chloride products. Due to its ubiquitous presence in environmental compartments and the constant exposure of the general population through ingestion, inhalation, and dermal absorption, this compound has been subjected to extensive in vivo and in vitro toxicological studies. Despite the available information, research on the cytotoxicity of di (2-ethylhexyl) phthalate in mammalian cells is relatively limited.In this paper, an in vitro multi-parametric approach was used to provide further mechanistic data on the toxic activity of this chemical in Vero and HaCaT cells. Our results reveal that a 24 h exposure to di (2-ethylhexyl) phthalate causes, in both cell lines, an inhibition of cell proliferation that was linked to cell cycle delay at the G1 phase. Concomitantly, the tested compound induces mild endoplasmic reticulum stress which leads to an adaptive rather than a pro-apoptotic response in mammalian cells. These findings demonstrate that there are multiple potential cellular targets of di (2-ethylhexyl) phthalate-induced toxicity and the need to develop further experimental studies for the risk assessment of this ubiquitous plasticizer. PMID:26514933

  4. Comparative studies on calotropins DI and DII from the latex of Calotropis gigantea.

    PubMed

    Sengupta, A; Bhattacharya, D; Pal, G; Sinha, N K

    1984-07-01

    Autodigestion of two cysteine proteinases, calotropins DI and DII isolated from the latex of Calotropis gigantea, has been studied at pH 7.5 and 37 degrees C in the presence of an activating agent. Calotropin DI is more susceptible to autodigestion than calotropin DII. During autodigestion no interconversion of one calotropin to another has occurred, as verified by polyacrylamide gel electrophoresis in the presence and absence of sodium dodecyl sulfate. Immunologically, both calotropins are closely related, but they differ from papain and ficin. Both calotropins have blocked N-terminal amino acid residues. Their C-terminal amino acid sequences, determined by treatment with carboxypeptidase Y, are -(Pro, Ala)-Ala-Val-Tyr for calotropin DI and -(Ala, Val)-Ala-Pro-Tyr for calotropin DII. The tryptic peptide maps of their reduced and S-carboxymethylated derivatives suggest that both calotropins share a high proportion of common regions in their amino acid sequences. Calotropins DI and DII are two distinct proteinases, and they do not appear to be produced by autodigestion of a single precursor. Although they are inert to the common synthetic substrates of papain and ficin, their specificities toward oxidized insulin B chain are comparable to those of papain and ficin. PMID:6430236

  5. A thermal lensing study of a photolysis of di- t-butyl peroxide

    NASA Astrophysics Data System (ADS)

    Fuke, K.; Hasegawa, A.; Ueda, M.; Itoh, M.

    1981-11-01

    A photolysis of di- t-butyl peroxide (BOOB) was studied by using a thermal lensing technique. This technique is found to be applicable to the determination Of the rate Constants of the decay of t-butoxy radical (BO ) and the hydrogen abstraction reaction.

  6. Regioselectivity in the formation of di- and tri-6-O-mesitylenesulfonates of α-cyclodextrin.

    PubMed

    Yoshikiyo, Keisuke; Shinjo, Misaki; Matsui, Yoshihisa; Yamamoto, Tatsuyuki

    2015-01-12

    The quantitative analysis of the reaction products for α-cyclodextrin (α-CD) with mesitylenesulfonyl chloride (MessCl) showed that di- and tri-mesitylenesulfonylation of the primary hydroxy groups of α-CD is regioselective. The reaction of mono-6-O-mesitylenesulfonyl-α-CD with MessCl in pyridine gave less 6(A),6(C)-di-O-mesitylenesulfonyl-α-CD than 6(A),6(B)-di-O-mesitylenesulfonyl-α-CD. The reaction of 6(A),6(D)-di-O-mesitylenesulfonyl-α-CD with MessCl gave less 6(A),6(B),6(E)-tri-O-mesitylenesulfonyl-α-CD than 6(A),6(B),6(D)-tri-O-mesitylenesulfonyl-α-CD. These results indicate that the mesitylenesulfonyl group attached to glucopyranose-A (Glc-A) retards further mesitylenesulfonylation of the primary hydroxy group of Glc-C. The (1)H NMR spectra of these modified α-CDs showed that the signal for the primary hydroxy and anomeric protons of Glc-C are significantly shifted upfield by the mesitylenesulfonyl group of Glc-A. PMID:25464082

  7. 40 CFR 721.2094 - N,N′-di(alkyl heteromonocycle)amino chlorotriazine.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false N,Nâ²-di(alkyl heteromonocycle)amino chlorotriazine. 721.2094 Section 721.2094 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC SUBSTANCES CONTROL ACT SIGNIFICANT NEW USES OF CHEMICAL SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.2094...

  8. Production technology and characterization of Fior di latte cheeses made from sheep and goat milks.

    PubMed

    Faccia, M; Trani, A; Gambacorta, G; Loizzo, P; Cassone, A; Caponio, F

    2015-03-01

    Innovation in the small ruminant dairy sector faces structural challenges because dairies are often involved in breeding and produce cheeses that appeal essentially to local markets using traditional technologies and facilities. An investigation was carried out to produce Fior di latte, a traditional, soft pasta filata cheese, from sheep and goat milks at the farm level. Fior di latte is an Italian high-moisture, round mozzarella currently produced from cow and water buffalo milks; it is very popular in Europe. Cheesemaking trials were performed and the most appropriate technology proved to be a combination of direct acidification and lactic fermentation, with some modifications to the milk coagulation phase. The gross composition of the experimental cheeses was similar to that of bovine Fior di latte, and the overall hygienic quality was satisfactory even though the milk had not been pasteurized. The new cheeses were similar in appearance to the bovine type, but some specific features were detected. Besides the typical "goaty" and "sheepy" flavors, some novel and distinctive descriptors of odor, flavor, and texture were noted. Our experiment showed that good quality Fior di latte cheese that complies with microbiological requirements of the European legislation can be obtained from sheep and goat milks by appropriately modifying the cheesemaking technology. PMID:25547300

  9. Dose Reconstruction of Di-2-Ethylhexyl Phthalate Using a Simple Pharmacokinetic Model [Manuscript

    EPA Science Inventory

    Background In 2005, eight adults provided full volumes and times of urine voids during one normal work week. These samples were analyzed for four di-2-ethylhexyl phthalate (DEHP) metabolites. Participants also provided diary information on their diet, driving, and out¬door a...

  10. 21 CFR 178.2550 - 4-Hydroxymethyl-2,6-di-tert-butylphenol.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... (CONTINUED) INDIRECT FOOD ADDITIVES: ADJUVANTS, PRODUCTION AIDS, AND SANITIZERS Antioxidants and Stabilizers... concentration of the additive and any other permitted antioxidants in the finished food-contact article does not... 21 Food and Drugs 3 2014-04-01 2014-04-01 false 4-Hydroxymethyl-2,6-di-tert-butylphenol....

  11. Genetic Modifiers of the Physical Malformations in Velo-Cardio-Facial Syndrome/DiGeorge Syndrome

    ERIC Educational Resources Information Center

    Aggarwal, Vimla S.; Morrow, Bernice E.

    2008-01-01

    Velo-cardio-facial syndrome/DiGeorge syndrome (VCFS/DGS), the most common micro-deletion disorder in humans, is characterized by craniofacial, parathyroid, and thymic defects as well as cardiac outflow tract malformations. Most patients have a similar hemizygous 3 million base pair deletion on 22q11.2. Studies in mouse have shown that "Tbx1", a…

  12. EFFECTS OF SEWAGE SLUDGE ON DI-(2-ETHYLHEXYL) PHTHALATE UPTAKE BY PLANTS

    EPA Science Inventory

    Di-(2-ethylhexyl) phthalate (DEHP) is a priority organic pollutant frequently found in municipal sludges. reenhouse study was conducted to determine the effects of sludge on plant uptake of 14 C-DEHP (carbonyl labeled). lants grown included three food chain crops, lettuce (Lactuc...

  13. 40 CFR 721.9675 - Titanate [Ti6O13 (2-)], di-po-tas-sium.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Titanate , di-po-tas-sium. 721.9675 Section 721.9675 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC SUBSTANCES CONTROL ACT SIGNIFICANT NEW USES OF CHEMICAL SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.9675 Titanate ,...

  14. Method of dissolving metal oxides with di- or polyphosphonic acid and a redundant

    DOEpatents

    Horwitz, Earl P.; Chiarizia, Renato

    1996-01-01

    A method of dissolving metal oxides using a mixture of a di- or polyphosphonic acid and a reductant wherein each is present in a sufficient amount to provide a synergistic effect with respect to the dissolution of metal oxides and optionally containing corrosion inhibitors and pH adjusting agents.

  15. Partial attenuation of Marek's disease virus by manipulation of Di-codon bias

    Technology Transfer Automated Retrieval System (TEKTRAN)

    All species studied to date demonstrate a preference for certain codons over other synonymous codons (codon bias), a preference which is also observed for pairs of codons (di-codon bias). Previous studies using poliovirus and influenza virus as models have demonstrated the ability to cause attenuat...

  16. DiMeX: A Text Mining System for Mutation-Disease Association Extraction.

    PubMed

    Mahmood, A S M Ashique; Wu, Tsung-Jung; Mazumder, Raja; Vijay-Shanker, K

    2016-01-01

    The number of published articles describing associations between mutations and diseases is increasing at a fast pace. There is a pressing need to gather such mutation-disease associations into public knowledge bases, but manual curation slows down the growth of such databases. We have addressed this problem by developing a text-mining system (DiMeX) to extract mutation to disease associations from publication abstracts. DiMeX consists of a series of natural language processing modules that preprocess input text and apply syntactic and semantic patterns to extract mutation-disease associations. DiMeX achieves high precision and recall with F-scores of 0.88, 0.91 and 0.89 when evaluated on three different datasets for mutation-disease associations. DiMeX includes a separate component that extracts mutation mentions in text and associates them with genes. This component has been also evaluated on different datasets and shown to achieve state-of-the-art performance. The results indicate that our system outperforms the existing mutation-disease association tools, addressing the low precision problems suffered by most approaches. DiMeX was applied on a large set of abstracts from Medline to extract mutation-disease associations, as well as other relevant information including patient/cohort size and population data. The results are stored in a database that can be queried and downloaded at http://biotm.cis.udel.edu/dimex/. We conclude that this high-throughput text-mining approach has the potential to significantly assist researchers and curators to enrich mutation databases. PMID:27073839

  17. Analysis of tomographic mineralogical data using YaDiV—Overview and practical case study

    NASA Astrophysics Data System (ADS)

    Friese, Karl-Ingo; Cichy, Sarah B.; Wolter, Franz-Erich; Botcharnikov, Roman E.

    2013-07-01

    We introduce the 3D-segmentation and -visualization software YaDiV to the mineralogical application of rock texture analysis. YaDiV has been originally designed to process medical DICOM datasets. But due to software advancements and additional plugins, this open-source software can now be easily used for the fast quantitative morphological characterization of geological objects from tomographic datasets. In this paper, we give a summary of YaDiV's features and demonstrate the advantages of 3D-stereographic visualization and the accuracy of 3D-segmentation for the analysis of geological samples. For this purpose, we present a virtual and a real use case (here: experimentally crystallized and vesiculated magmatic rocks, corresponding to the composition of the 1991-1995 Unzen eruption, Japan). Especially the spacial representation of structures in YaDiV allows an immediate, intuitive understanding of the 3D-structures, which may not become clear by only looking on 2D-images. We compare our results of object number density calculations with the established classical stereological 3D-correction methods for 2D-images and show that it was possible to achieve a seriously higher quality and accuracy. The methods described in this paper are not dependent on the nature of the object. The fact, that YaDiV is open-source and users with programming skills can create new plugins themselves, may allow this platform to become applicable to a variety of geological scenarios from the analysis of textures in tiny rock samples to the interpretation of global geophysical data, as long as the data are provided in tomographic form.

  18. DiMeX: A Text Mining System for Mutation-Disease Association Extraction

    PubMed Central

    Mahmood, A. S. M. Ashique; Wu, Tsung-Jung; Mazumder, Raja; Vijay-Shanker, K.

    2016-01-01

    The number of published articles describing associations between mutations and diseases is increasing at a fast pace. There is a pressing need to gather such mutation-disease associations into public knowledge bases, but manual curation slows down the growth of such databases. We have addressed this problem by developing a text-mining system (DiMeX) to extract mutation to disease associations from publication abstracts. DiMeX consists of a series of natural language processing modules that preprocess input text and apply syntactic and semantic patterns to extract mutation-disease associations. DiMeX achieves high precision and recall with F-scores of 0.88, 0.91 and 0.89 when evaluated on three different datasets for mutation-disease associations. DiMeX includes a separate component that extracts mutation mentions in text and associates them with genes. This component has been also evaluated on different datasets and shown to achieve state-of-the-art performance. The results indicate that our system outperforms the existing mutation-disease association tools, addressing the low precision problems suffered by most approaches. DiMeX was applied on a large set of abstracts from Medline to extract mutation-disease associations, as well as other relevant information including patient/cohort size and population data. The results are stored in a database that can be queried and downloaded at http://biotm.cis.udel.edu/dimex/. We conclude that this high-throughput text-mining approach has the potential to significantly assist researchers and curators to enrich mutation databases. PMID:27073839

  19. In vitro binding of 3,5-di-iodo-L-thyronine to rat liver mitochondria.

    PubMed

    Goglia, F; Lanni, A; Horst, C; Moreno, M; Thoma, R

    1994-12-01

    In this study we have demonstrated that specific binding sites for 3,5-di-iodo-L-thyronine (3,5-T2) can be detected in rat liver mitochondria. After incubation with the homogenate, liver mitochondria bound only a small portion of [3,5-125I]T2. The addition of a 100-fold excess of unlabelled 3,5-T2 caused the displacement of on average 50-60% of the [3,5-125I]T2 bound. Specific binding of 3,5-T2 to rat liver mitochondria occurred rapidly; a maximum was achieved after 5 min. Maximal binding was obtained at 37 degrees C, while at 0 degrees C and 20 degrees C the values were only slightly lower. Binding was maximal at pH 7.0; mean (+/- S.E.M.) values for the apparent association constant and the binding capacity (calculated at pH 7.0, 0 degrees C and after 30 min of incubation) were 0.5 +/- 0.04 x 10(8) M-1 and 0.4 +/- 0.04 pmol/mg mitochondrial protein respectively. The specificity of binding, examined in competition studies, followed the order: 3,5-T2 > 3,3'-di-iodo-L-thyronine > 3',3,5-tri-iodo-L-thyronine > thyroxine. Other iodothyronines (3',5'-di-iodo-L-thyronine, 3,5-di-iodo-D-thyronine, 3,3',5'-tri-iodo-L-thyronine, 3-iodo-L-thyronine and 3,5-di-iodothyroacetic acid) showed little or no competition. This suggests that the specific 3,5-T2 binding sites could be of biological relevance with respect to the understanding of the mechanism of physiological action of thyroid hormones at the cellular level. PMID:7893345

  20. Ultraviolet stimulated melanogenesis by human melanocytes is augmented by di-acyl glycerol but not TPA

    SciTech Connect

    Friedmann, P.S.; Wren, F.E.; Matthews, J.N. )

    1990-02-01

    Epidermal melanocytes (MC) synthesize melanin in response to ultraviolet radiation (UVR). The mechanisms mediating the UV-induced activation of melanogenesis are unknown but since UVR induces turnover of membrane phospholipids generating prostaglandins (PGs) and other products, it is possible that one of these might provide the activating signal. We have examined the effects of prostaglandins (PGs) E1, E2, D2, F2 alpha, and di-acyl glycerol upon the UV-induced responses of cultured human MC and the Cloudman S91 melanoma cell line. The PGs had little effect on unirradiated cells and did not alter the response to UVR in either human MC or S91 melanoma cells. However, a synthetic analogue of di-acyl glycerol, 1-oleyl 2-acetyl glycerol (OAG), caused a significant (P less than 0.0001), dose-related augmentation of melanin content both in human MC (seven-fold) and S91 cells (three-fold). UVR caused a significant augmentation of the OAG-induced melanogenesis of both human MC and S91 cells. Since OAG is known to activate protein kinase C, it was possible that the observed modulation of the UVR signal could be via that pathway. Di-octanoyl glycerol, another di-acyl glycerol, which activates kinase C, caused a small (70%) increase in melanogenesis in MC which was not altered by UVR. However, 12-0 tetradecanoyl phorbol 13-acetate (TPA), a potent activator of protein kinase C, had no significant effect on either basal or UV-induced melanin synthesis in either cell type. These data suggest that the UV-induced signal activating melanogenesis could be mediated by di-acyl glycerol. Furthermore, they imply that the signal is transduced via an alternative, pathway that might be independent of protein kinase C.

  1. Di-Ras2 Protein Forms a Complex with SmgGDS Protein in Brain Cytosol in Order to Be in a Low Affinity State for Guanine Nucleotides.

    PubMed

    Ogita, Yoshitaka; Egami, Sachiko; Ebihara, Arisa; Ueda, Nami; Katada, Toshiaki; Kontani, Kenji

    2015-08-14

    The Ras family of small GTPases function in a wide variety of biological processes as "molecular switches" by cycling between inactive GDP-bound and active GTP-bound forms. Di-Ras1 and Di-Ras2 were originally identified as small GTPases forming a distinct subgroup of the Ras family. Di-Ras1/Di-Ras2 mRNAs are detected predominantly in brain and heart tissues. Biochemical analysis of Di-Ras1/Di-Ras2 has revealed that they have little GTPase activity and that their intrinsic guanine-nucleotide exchange rates are much faster than that of H-Ras. Yet little is known about the biological role(s) of Di-Ras1/Di-Ras2 or of how their activities are regulated. In the present study we found that endogenous Di-Ras2 co-purifies with SmgGDS from rat brain cytosol. Size-exclusion chromatography of purified recombinant proteins showed that Di-Ras2 forms a high affinity complex with SmgGDS. SmgGDS is a guanine nucleotide exchange factor with multiple armadillo repeats and has recently been shown to specifically activate RhoA and RhoC. In contrast to the effect on RhoA, SmgGDS does not act as a guanine nucleotide exchange factor for Di-Ras2 but instead tightly associates with Di-Ras2 to reduce its binding affinity for guanine nucleotides. Finally, pulse-chase analysis revealed that Di-Ras2 binds, in a C-terminal CAAX motif-dependent manner, to SmgGDS immediately after its synthesis. This leads to increased Di-Ras2 stability. We thus propose that isoprenylated Di-Ras2 forms a tight complex with SmgGDS in cytosol immediately after its synthesis, which lowers its affinity for guanine nucleotides. PMID:26149690

  2. Intestinal GPS: bile and bicarbonate control cyclic di-GMP to provide Vibrio cholerae spatial cues within the small intestine

    PubMed Central

    Koestler, Benjamin J; Waters, Christopher M

    2014-01-01

    The second messenger cyclic di-GMP (c-di-GMP) regulates numerous phenotypes in response to environmental stimuli to enable bacteria to transition between different lifestyles. Here we discuss our recent findings that the human pathogen Vibrio cholerae recognizes 2 host-specific signals, bile and bicarbonate, to regulate intracellular c-di-GMP. We have demonstrated that bile acids increase intracellular c-di-GMP to promote biofilm formation. We have also shown that this bile-mediated increase of intracellular c-di-GMP is negated by bicarbonate, and that this interaction is dependent on pH, suggesting that V. cholerae uses these 2 environmental cues to sense and adapt to its relative location in the small intestine. Increased intracellular c-di-GMP by bile is attributed to increased c-di-GMP synthesis by 3 diguanylate cyclases (DGCs) and decreased expression of one phosphodiesterase (PDE) in the presence of bile. The molecular mechanisms by which bile controls the activity of the 3 DGCs and the regulators of bile-mediated transcriptional repression of the PDE are not yet known. Moreover, the impact of varying concentrations of bile and bicarbonate at different locations within the small intestine and the response of V. cholerae to these cues remains unclear. The native microbiome and pharmaceuticals, such as omeprazole, can impact bile and pH within the small intestine, suggesting these are potential unappreciated factors that may alter V. cholerae pathogenesis. PMID:25621620

  3. Dimeric c-di-GMP is required for post-translational regulation of alginate production in Pseudomonas aeruginosa

    SciTech Connect

    Whitney, John C.; Robinson, Howard; Whitfield, Gregory B.; Marmont, Lindsey S.; Yip, Patrick; Neculai, A. Mirela; Lobsanov, Yuri D.; Ohman, Dennis E.; Howell, P. Lynne

    2015-05-15

    Pseudomonas aeruginosa is an opportunistic human pathogen that secretes the exopolysaccharide alginate during infection of the respiratory tract of individuals afflicted with cystic fibrosis and chronic obstructive pulmonary disease. Among the proteins required for alginate production, Alg44 has been identified as an inner membrane protein whose bis-(3',5')-cyclic dimeric guanosine monophosphate (c-di-GMP) binding activity post-translationally regulates alginate secretion. In this study, we report the 1.8 crystal structure of the cytoplasmic region of Alg44 in complex with dimeric self-intercalated c-di-GMP and characterize its dinucleotide-binding site using mutational analysis. The structure shows that the c-di-GMP binding region of Alg44 adopts a PilZ domain fold with a dimerization mode not previously observed for this family of proteins. Moreover, calorimetric binding analysis of residues in the c-di-GMP binding site demonstrate that mutation of Arg-17 and Arg-95 alters the binding stoichiometry between c-di-GMP and Alg44 from 2:1 to 1:1. Introduction of these mutant alleles on the P. aeruginosa chromosome show that the residues required for binding of dimeric c-di-GMP in vitro are also required for efficient alginate production in vivo. Our results suggest that the dimeric form of c-di-GMP represents the biologically active signaling molecule needed for the secretion of an important virulence factor produced by P. aeruginosa.

  4. STING-Dependent Recognition of Cyclic di-AMP Mediates Type I Interferon Responses during Chlamydia trachomatis Infection

    PubMed Central

    Barker, Jeffrey R.; Koestler, Benjamin J.; Carpenter, Victoria K.; Burdette, Dara L.; Waters, Christopher M.; Vance, Russell E.; Valdivia, Raphael H.

    2013-01-01

    ABSTRACT STING (stimulator of interferon [IFN] genes) initiates type I IFN responses in mammalian cells through the detection of microbial nucleic acids. The membrane-bound obligate intracellular bacterium Chlamydia trachomatis induces a STING-dependent type I IFN response in infected cells, yet the IFN-inducing ligand remains unknown. In this report, we provide evidence that Chlamydia synthesizes cyclic di-AMP (c-di-AMP), a nucleic acid metabolite not previously identified in Gram-negative bacteria, and that this metabolite is a prominent ligand for STING-mediated activation of IFN responses during infection. We used primary mouse lung fibroblasts and HEK293T cells to compare IFN-β responses to Chlamydia infection, c-di-AMP, and other type I IFN-inducing stimuli. Chlamydia infection and c-di-AMP treatment induced type I IFN responses in cells expressing STING but not in cells expressing STING variants that cannot sense cyclic dinucleotides but still respond to cytoplasmic DNA. The failure to induce a type I IFN response to Chlamydia and c-di-AMP correlated with the inability of STING to relocalize from the endoplasmic reticulum to cytoplasmic punctate signaling complexes required for IFN activation. We conclude that Chlamydia induces STING-mediated IFN responses through the detection of c-di-AMP in the host cell cytosol and propose that c-di-AMP is the ligand predominantly responsible for inducing such a response in Chlamydia-infected cells. PMID:23631912

  5. Dimeric c-di-GMP is required for post-translational regulation of alginate production in Pseudomonas aeruginosa

    DOE PAGESBeta

    Whitney, John C.; Robinson, Howard; Whitfield, Gregory B.; Marmont, Lindsey S.; Yip, Patrick; Neculai, A. Mirela; Lobsanov, Yuri D.; Ohman, Dennis E.; Howell, P. Lynne

    2015-05-15

    Pseudomonas aeruginosa is an opportunistic human pathogen that secretes the exopolysaccharide alginate during infection of the respiratory tract of individuals afflicted with cystic fibrosis and chronic obstructive pulmonary disease. Among the proteins required for alginate production, Alg44 has been identified as an inner membrane protein whose bis-(3',5')-cyclic dimeric guanosine monophosphate (c-di-GMP) binding activity post-translationally regulates alginate secretion. In this study, we report the 1.8 Å crystal structure of the cytoplasmic region of Alg44 in complex with dimeric self-intercalated c-di-GMP and characterize its dinucleotide-binding site using mutational analysis. The structure shows that the c-di-GMP binding region of Alg44 adopts a PilZmore » domain fold with a dimerization mode not previously observed for this family of proteins. Moreover, calorimetric binding analysis of residues in the c-di-GMP binding site demonstrate that mutation of Arg-17 and Arg-95 alters the binding stoichiometry between c-di-GMP and Alg44 from 2:1 to 1:1. Introduction of these mutant alleles on the P. aeruginosa chromosome show that the residues required for binding of dimeric c-di-GMP in vitro are also required for efficient alginate production in vivo. Our results suggest that the dimeric form of c-di-GMP represents the biologically active signaling molecule needed for the secretion of an important virulence factor produced by P. aeruginosa.« less

  6. Dimeric c-di-GMP is required for post-translational regulation of alginate production in Pseudomonas aeruginosa

    SciTech Connect

    Whitney, John C.; Robinson, Howard; Whitfield, Gregory B.; Marmont, Lindsey S.; Yip, Patrick; Neculai, A. Mirela; Lobsanov, Yuri D.; Ohman, Dennis E.; Howell, P. Lynne

    2015-05-15

    Pseudomonas aeruginosa is an opportunistic human pathogen that secretes the exopolysaccharide alginate during infection of the respiratory tract of individuals afflicted with cystic fibrosis and chronic obstructive pulmonary disease. Among the proteins required for alginate production, Alg44 has been identified as an inner membrane protein whose bis-(3',5')-cyclic dimeric guanosine monophosphate (c-di-GMP) binding activity post-translationally regulates alginate secretion. In this study, we report the 1.8 Å crystal structure of the cytoplasmic region of Alg44 in complex with dimeric self-intercalated c-di-GMP and characterize its dinucleotide-binding site using mutational analysis. The structure shows that the c-di-GMP binding region of Alg44 adopts a PilZ domain fold with a dimerization mode not previously observed for this family of proteins. Moreover, calorimetric binding analysis of residues in the c-di-GMP binding site demonstrate that mutation of Arg-17 and Arg-95 alters the binding stoichiometry between c-di-GMP and Alg44 from 2:1 to 1:1. Introduction of these mutant alleles on the P. aeruginosa chromosome show that the residues required for binding of dimeric c-di-GMP in vitro are also required for efficient alginate production in vivo. Our results suggest that the dimeric form of c-di-GMP represents the biologically active signaling molecule needed for the secretion of an important virulence factor produced by P. aeruginosa.

  7. Structural Analysis of the GGDEF-EAL Domain-Containing c-di-GMP Receptor FimX

    SciTech Connect

    Navarro, M.; De, N; Bae, N; Wang, Q; Sondermann, H

    2009-01-01

    Bacterial pathogenesis involves social behavior including biofilm formation and swarming, processes that are regulated by the bacterially unique second messenger cyclic di-GMP (c-di-GMP). Diguanylate cyclases containing GGDEF and phosphodiesterases containing EAL domains have been identified as the enzymes controlling cellular c-di-GMP levels, yet less is known regarding signal transmission and the targets of c-di-GMP. FimX, a protein from Pseudomonas aeruginosa that governs twitching motility, belongs to a large subfamily containing both GGDEF and EAL domains. Biochemical and structural analyses reveals its function as a high-affinity receptor for c-di-GMP. A model for full-length FimX was generated combining solution scattering data and crystal structures of the degenerate GGDEF and EAL domains. Although FimX forms a dimer in solution via the N-terminal domains, a crystallographic EAL domain dimer suggests modes for the regulation of FimX by c-di-GMP binding. The results provide the structural basis for c-di-GMP sensing via degenerate phosphodiesterases.

  8. Identification of a cyclic-di-GMP-modulating response regulator that impacts biofilm formation in a model sulfate reducing bacterium

    PubMed Central

    Rajeev, Lara; Luning, Eric G.; Altenburg, Sara; Zane, Grant M.; Baidoo, Edward E. K.; Catena, Michela; Keasling, Jay D.; Wall, Judy D.; Fields, Matthew W.; Mukhopadhyay, Aindrila

    2014-01-01

    We surveyed the eight putative cyclic-di-GMP-modulating response regulators (RRs) in Desulfovibrio vulgaris Hildenborough that are predicted to function via two-component signaling. Using purified proteins, we examined cyclic-di-GMP (c-di-GMP) production or turnover in vitro of all eight proteins. The two RRs containing only GGDEF domains (DVU2067, DVU0636) demonstrated c-di-GMP production activity in vitro. Of the remaining proteins, three RRs with HD-GYP domains (DVU0722, DVUA0086, and DVU2933) were confirmed to be Mn2+-dependent phosphodiesterases (PDEs) in vitro and converted c-di-GMP to its linear form, pGpG. DVU0408, containing both c-di-GMP production (GGDEF) and degradation domains (EAL), showed c-di-GMP turnover activity in vitro also with production of pGpG. No c-di-GMP related activity could be assigned to the RR DVU0330, containing a metal-dependent phosphohydrolase HD-OD domain, or to the HD-GYP domain RR, DVU1181. Studies included examining the impact of overexpressed cyclic-di-GMP-modulating RRs in the heterologous host E. coli and led to the identification of one RR, DVU0636, with increased cellulose production. Evaluation of a transposon mutant in DVU0636 indicated that the strain was impaired in biofilm formation and demonstrated an altered carbohydrate:protein ratio relative to the D. vulgaris wild type biofilms. However, grown in liquid lactate/sulfate medium, the DVU0636 transposon mutant showed no growth impairment relative to the wild-type strain. Among the eight candidates, only the transposon disruption mutant in the DVU2067 RR presented a growth defect in liquid culture. Our results indicate that, of the two diguanylate cyclases (DGCs) that function as part of two-component signaling, DVU0636 plays an important role in biofilm formation while the function of DVU2067 has pertinence in planktonic growth. PMID:25120537

  9. DiPyMe in SDS Micelles: Artifacts and Their Implications in the Interpretation of Micellar Properties.

    PubMed

    Fowler, Michael; Hisko, Victoria; Henderson, Jason; Casier, Remi; Li, Lu; Thoma, Janine Lydia; Duhamel, Jean

    2015-11-10

    This study provides experimental evidence that di(1-pyrenylmethyl) ether or DiPyMe, a well-known fluorescent probe employed to determine the microviscosity of surfactant or polymeric micelles, is being hydrolyzed in the presence of water upon UV irradiation. This effect was established from a careful analysis of the fluorescence spectra and decays acquired with aqueous solutions of DiPyMe dissolved in micelles of sodium dodecyl sulfate (SDS). The size of the SDS micelles could be adjusted from an aggregation number (N(agg)) of 70 to 172 by increasing the ionic strength of the aqueous solution from 0.0 to 0.5 M NaCl. The hydrolysis of DiPyMe was much reduced in the larger SDS micelles. While the degradation of DiPyMe in aqueous solutions of SDS micelles affected the analysis of the fluorescence spectra, model-free analysis (MFA) of the fluorescence decays of DiPyMe could reliably retrieve the rate constant ⟨k⟩ of excimer formation for DiPyMe. After calibration with mixtures of organic solvents of known macroscopic viscosity, the ⟨k⟩ values obtained for DiPyMe yielded the microviscosity (μη) of the SDS micelles as a function of salt concentration. The μη was found to increase from 4.0 to 8.8 mPa·s as the salt concentration increased from 0.0 to 0.5 M. This study demonstrated that, regardless of the problem of its hydrolysis that jeopardizes its use in steady-state fluorescence experiments, DiPyMe remains an extremely valuable probe for describing the microviscosity of hydrophobic domains in aqueous solution as long as its decays are analyzed with a model that accounts for the presence of degradation products as the MFA does. PMID:26465066

  10. Cyclic di-AMP Is Critical for Listeria monocytogenes Growth, Cell Wall Homeostasis, and Establishment of Infection

    PubMed Central

    Witte, Chelsea E.; Whiteley, Aaron T.; Burke, Thomas P.; Sauer, John-Demian; Portnoy, Daniel A.; Woodward, Joshua J.

    2013-01-01

    ABSTRACT Listeria monocytogenes infection leads to robust induction of an innate immune signaling pathway referred to as the cytosolic surveillance pathway (CSP), characterized by expression of beta interferon (IFN-β) and coregulated genes. We previously identified the IFN-β stimulatory ligand as secreted cyclic di-AMP. Synthesis of c-di-AMP in L. monocytogenes is catalyzed by the diadenylate cyclase DacA, and multidrug resistance transporters are necessary for secretion. To identify additional bacterial factors involved in L. monocytogenes detection by the CSP, we performed a forward genetic screen for mutants that induced altered levels of IFN-β. One mutant that stimulated elevated levels of IFN-β harbored a transposon insertion in the gene lmo0052. Lmo0052, renamed here PdeA, has homology to a cyclic di-AMP phosphodiesterase, GdpP (formerly YybT), of Bacillus subtilis and is able to degrade c-di-AMP to the linear dinucleotide pApA. Reduction of c-di-AMP levels by conditional depletion of the di-adenylate cyclase DacA or overexpression of PdeA led to marked decreases in growth rates, both in vitro and in macrophages. Additionally, mutants with altered levels of c-di-AMP had different susceptibilities to peptidoglycan-targeting antibiotics, suggesting that the molecule may be involved in regulating cell wall homeostasis. During intracellular infection, increases in c-di-AMP production led to hyperactivation of the CSP. Conditional depletion of dacA also led to increased IFN-β expression and a concomitant increase in host cell pyroptosis, a result of increased bacteriolysis and subsequent bacterial DNA release. These data suggest that c-di-AMP coordinates bacterial growth, cell wall stability, and responses to stress and plays a crucial role in the establishment of bacterial infection. PMID:23716572

  11. 8 de noviembre de 2006: Mercurio pasea sobre el disco solar (Micro eclipse anular de Sol o el segundo tránsito de Mercurio del siglo XXI)

    NASA Astrophysics Data System (ADS)

    Mallamaci, C. C.

    On Wendsday November 8, 2006, the second transit of Mercury over the Sun of the 21st. Century, took place. In this work we present the principal characteristics of the phenomenon ocurrence, the visibility region and the local circumstances for some locations of Argentina and other countries of the world. Full TEXT IN SPANISH

  12. The soybean GmDi19-5 interacts with GmLEA3.1 and increases sensitivity of transgenic plants to abiotic stresses

    PubMed Central

    Feng, Zhi-Juan; Cui, Xiao-Yu; Cui, Xi-Yan; Chen, Ming; Yang, Guang-Xiao; Ma, You-Zhi; He, Guang-Yuan; Xu, Zhao-Shi

    2015-01-01

    Drought-induced (Di19) proteins played important roles in plant growth, development, and abiotic stress responses. In the present study, a total of seven Di19 genes were identified in soybean. Each soybean Di19 gene showed specific responses to salt, drought, oxidative, and ABA stresses based on expression profiles. With a relatively higher transcript level among Di19 members under four stress treatments, GmDi19-5 was selected for detailed analysis. Inhibitor assays revealed that ABA inhibitor (Fluridone) or H2O2 inhibitor (DMTU) was involved in the drought- or salt-induced transcription of GmDi19-5. The GUS activity driven by the GmDi19-5 promoter was induced by salt, PEG, ABA, and MV treatments and tended to be accumulated in the vascular bundles and young leaves. A subcellular localization assay showed that GmDi19-5 protein localized in the nucleus. Further investigation showed that GmDi19-5 protein was involved in the interaction with GmLEA3.1. Overexpression of GmDi19-5 increased sensitivity of transgenic Arabidopsis plants to salt, drought, oxidative, and ABA stresses and regulated expression of several ABA/stress-associated genes. This present investigation showed that GmDi19-5 functioned as a negative factor under abiotic stresses and was involved in ABA and SOS signaling pathway by altering transcription of stress-associated genes. PMID:25852726

  13. Crystal structure of [N,N′-bis­(4-methyl­phen­yl)-1,2-di­phenyl­ethane-1,2-di­imine-κ2 N,N′]di­chlorido­palladium(II) methanol monosolvate

    PubMed Central

    Peñaloza, Alfredo; Fronczek, Frank R.; Isovitsch, Ralph

    2015-01-01

    The title compound, [PdCl2(C28H24N2)]·CH3OH, was pre­pared from the reaction of PdCl2(DMSO)2 (DMSO is di­methyl sulfoxide) and N,N′-bis­(4-methyl­phen­yl)-1,2-di­phenyl­ethane-1,2-di­imine in methanol. The chelating di­imine core of the title compound deviates slightly from planarity, with an N—C—C—N torsion angle of 5.3 (3)°. Delocalization in the di­imine core is indicated by N—C and C—C bonds that are, respectively, longer and shorter than those found in related nonchelating di­imines. The distorted square-planar coordination environment around the PdII atom is manifested as bond angles that are smaller and larger than 90°, and palladacycle torsion angles of −173.22 (16) and 167.06 (16)°. These deviations are attributed to the small bite angle of 79.13 (8)° of the di­imine chelate. The crystal packing exhibits weak inter­molecular hydrogen-bonding inter­actions involving aromatic H atoms, Cl atoms and inter­calated methanol solvent mol­ecules, defining layers parallel to (010). PMID:26396867

  14. Utero-vaginal aplasia (Mayer-Rokitansky-Küster-Hauser syndrome) associated with deletions in known DiGeorge or DiGeorge-like loci

    PubMed Central

    2011-01-01

    Background Mayer-Rokitansky-Küster-Hauser (MRKH) syndrome is characterized by congenital aplasia of the uterus and the upper part of the vagina in women showing normal development of secondary sexual characteristics and a normal 46, XX karyotype. The uterovaginal aplasia is either isolated (type I) or more frequently associated with other malformations (type II or Müllerian Renal Cervico-thoracic Somite (MURCS) association), some of which belong to the malformation spectrum of DiGeorge phenotype (DGS). Its etiology remains poorly understood. Thus the phenotypic manifestations of MRKH and DGS overlap suggesting a possible genetic link. This would potentially have clinical consequences. Methods We searched DiGeorge critical chromosomal regions for chromosomal anomalies in a cohort of 57 subjects with uterovaginal aplasia (55 women and 2 aborted fetuses). For this candidate locus approach, we used a multiplex ligation-dependent probe amplification (MLPA) assay based on a kit designed for investigation of the chromosomal regions known to be involved in DGS. The deletions detected were validated by Duplex PCR/liquid chromatography (DP/LC) and/or array-CGH analysis. Results We found deletions in four probands within the four chromosomal loci 4q34-qter, 8p23.1, 10p14 and 22q11.2 implicated in almost all cases of DGS syndrome. Conclusion Uterovaginal aplasia appears to be an additional feature of the broad spectrum of the DGS phenotype. The DiGeorge critical chromosomal regions may be candidate loci for a subset of MRKH syndrome (MURCS association) individuals. However, the genes mapping at the sites of these deletions involved in uterovaginal anomalies remain to be determined. These findings have consequences for clinical investigations, the care of patients and their relatives, and genetic counseling. PMID:21406098

  15. Crystal structure of 9,10-bis­(1,3-di­thiol-2-yl­idene)-9,10-di­hydro­anthracene

    PubMed Central

    Ren, Yi; Lee, Semin; Bertke, Jeffery A.; Moore, Jeffrey S.

    2015-01-01

    The crystal structure of the well-studied 9,10-bis­(1,3-di­thiol-2-yl­idene)-9,10-di­hydro­anthracene mol­ecule, C20H12S4, (I), also known as exTTF, is reported. The mol­ecular structure of (I) consists of a di­hydro­anthracene moiety with two 1,3-di­thiol-2-yl­idene substituents. This is a saddle-shaped mol­ecule, which inter­acts with a close neighbor through various π–π and C—H⋯π contacts to form a ‘dimer’. These ‘dimers’ inter­act through a series of C—H⋯S and C—H⋯π contacts to construct a complex three-dimensional extended structure. PMID:26870408

  16. Crystal structure of tri-aqua-(2,6-di-methyl-pyrazine-κN (4))bis-(thio-cyanato-κN)manganese(II) 2,5-di-methyl-pyrazine disolvate.

    PubMed

    Suckert, Stefan; Wöhlert, Susanne; Jess, Inke; Näther, Christian

    2015-12-01

    In the crystal structure of the title complex, [Mn(NCS)2(C6H8N2)(H2O)3]·2C6H8N2, the Mn(II) cation is coordinated by two terminally N-bonded thio-cyanate anions, three water mol-ecules and one 2,6-di-methyl-pyrazine ligand within a slightly distorted N3O3 octa-hedral geometry; the entire complex mol-ecule is generated by the application of a twofold rotation axis. The asymmetric unit also contains an uncoordinating 2,5-di-methyl-pyrazine ligand in a general position. Obviously, the coordination to the 2,6-di-methyl-pyrazine ligand is preferred because coordination to the 2,5-di-methyl-pyrazine is hindered due to the bulky methyl group proximate to the N atom. The discrete complexes are linked by water-O-H⋯N(2,6-di-methyl-pyzazine/2,5-di-methyl-pyza-zine) hydrogen bonding, forming a three-dimensional network. In the crystal, mol-ecules are arranged in a way that cavities are formed in which unspecified, disordered solvent molecules reside. These were modelled employing the SQUEEZE routine in PLATON [Spek (2015 ▸). Acta Cryst. C71, 9-18]. The composition of the unit cell does not take into account the presence of the unspecified solvent. PMID:26870435

  17. A Versatile Room-Temperature Route to Di- and Trisubstituted Allenes Using Flow-Generated Diazo Compounds**

    PubMed Central

    Poh, Jian-Siang; Tran, Duc N; Battilocchio, Claudio; Hawkins, Joel M; Ley, Steven V

    2015-01-01

    A copper-catalyzed coupling reaction between flow-generated unstabilized diazo compounds and terminal alkynes provides di- and trisubstituted allenes. This extremely mild and rapid transformation is highly tolerant of several functional groups. PMID:26013774

  18. 2,6-Di(arylamino)-3-fluoropyridine Derivatives as HIV Non-Nucleoside Reverse Transcriptase Inhibitors.

    PubMed

    Sergeyev, Sergey; Yadav, Ashok Kumar; Franck, Philippe; Michiels, Johan; Lewi, Paul; Heeres, Jan; Vanham, Guido; Ariën, Kevin K; Vande Velde, Christophe M L; De Winter, Hans; Maes, Bert U W

    2016-03-10

    New non-nucleoside reverse transcriptase inhibitors (NNRTI), which are similar in structure to earlier described di(arylamino)pyrimidines but featuring a 2,6-di(arylamino)-3-fluoropyridine, 2,4-di(arylamino)-5-fluoropyrimidine, or 1,3-di(arylamino)-4-fluorobenzene moiety instead of a 2,4-disubstituted pyrimidine moiety, are reported. The short and practical synthesis of novel NNRTI relies on two sequential Pd-catalyzed aminations as the key steps. It is demonstrated through direct comparison with reference compounds that the presence of a fluorine atom increases the in vitro anti-HIV activity, both against the wild type virus and drug-resistant mutant strains. PMID:26785139

  19. Vibrio cholerae VpsT Regulates Matrix Production and Motility by Directly Sensing Cyclic di-GMP

    SciTech Connect

    Krasteva, P.; Fong, J; Shikuma, N; Beyhan, S; Navarro, M; Yildiz, F; Sondermann, H

    2010-01-01

    Microorganisms can switch from a planktonic, free-swimming life-style to a sessile, colonial state, called a biofilm, which confers resistance to environmental stress. Conversion between the motile and biofilm life-styles has been attributed to increased levels of the prokaryotic second messenger cyclic di-guanosine monophosphate (c-di-GMP), yet the signaling mechanisms mediating such a global switch are poorly understood. Here we show that the transcriptional regulator VpsT from Vibrio cholerae directly senses c-di-GMP to inversely control extracellular matrix production and motility, which identifies VpsT as a master regulator for biofilm formation. Rather than being regulated by phosphorylation, VpsT undergoes a change in oligomerization on c-di-GMP binding.

  20. Bromine Incorporation in Regulated and Emerging DBPs and the Relative Predominance of Mono, Di and Trihalogenated DBPs - SLIDES

    EPA Science Inventory

    Examination of bromine incorporation in emerging DBPs vs that of regulated DBPs Study of predominance of di- vs trihalogenated species in different DBP classes Better understand and characterize exposure to DBPs of health concern

  1. Oxidation of 2,6-di-tert-butyl-4-methylphenol. The structure of C14H22O3

    USGS Publications Warehouse

    Yohe, G.R.; Dunbar, J.E.; Lansford, M.W.; Pedrotti, R.L.; Scheidt, F.M.; Lee, F.G.H.; Smith, E.C.

    1959-01-01

    The acidic compound C14H22O3, previously reported without assignment of structure as an oxidation product of 2,6-di-tert-butyl-4-methylphenol, is now believed to be DL-trans-5,6-di-tert-butyl-2-hydroxy-1,4-diketo-2-cyclohexene (I). Chemical properties are described and infrared spectra are presented in support of this structure. This structure is of interest in relation to the problem of the existence of o-di-tert-alkylbenzene derivatives. The relatively easy racemization of optically active I suggests that its completely enolized form, 5,6-di-tert-butyl-1,2,4-trihydroxybenzene, is capable of transitory existence.

  2. MeDiA: Mean Distance Association and Its Applications in Nonlinear Gene Set Analysis

    PubMed Central

    Peng, Hesen; Ma, Junjie; Bai, Yun; Lu, Jianwei; Yu, Tianwei

    2015-01-01

    Probabilistic association discovery aims at identifying the association between random vectors, regardless of number of variables involved or linear/nonlinear functional forms. Recently, applications in high-dimensional data have generated rising interest in probabilistic association discovery. We developed a framework based on functions on the observation graph, named MeDiA (Mean Distance Association). We generalize its property to a group of functions on the observation graph. The group of functions encapsulates major existing methods in association discovery, e.g. mutual information and Brownian Covariance, and can be expanded to more complicated forms. We conducted numerical comparison of the statistical power of related methods under multiple scenarios. We further demonstrated the application of MeDiA as a method of gene set analysis that captures a broader range of responses than traditional gene set analysis methods. PMID:25915206

  3. Preliminary experimental results from a dichoptic vision system (DiVS)

    NASA Astrophysics Data System (ADS)

    Browne, Michael P.; Moffitt, Kirk; Hopper, Darrel G.; Fath, Bridget

    2011-06-01

    A dichoptic HMD vision system can provide an expansive and highly detailed visual experience by presenting a large FOV, lower quality image to one eye and a small FOV, higher quality image to the other. We compared a benchtop dichoptic vision system (DiVS) to a reference binocular system (RBS) using both subjective ratings and a performance test. Subjective ratings were directed at questions involving image quality, viewing comfort and presence or immersion. The performance test required observers to scan the scene to locate a target and then make an identification. Response times were collected for each component of this task. Target acquisition times were found to be much shorter for the DiVS condition while target identification times were longer. Total time to acquire and identify a target was found to be significantly shorter for a dichoptic system.

  4. Carbon Nanofiber Incorporated Silica Based Aerogels with Di-Isocyanate Cross-Linking

    NASA Technical Reports Server (NTRS)

    Vivod, Stephanie L.; Meador, Mary Ann B.; Capadona, Lynn A.; Sullivan, Roy M.; Ghosn, Louis J.; Clark, Nicholas; McCorkle, Linda

    2008-01-01

    Lightweight materials with excellent thermal insulating properties are highly sought after for a variety of aerospace and aeronautic applications. (1) Silica based aerogels with their high surface area and low relative densities are ideal for applications in extreme environments such as insulators for the Mars Rover battery. (2) However, the fragile nature of aerogel monoliths prevents their widespread use in more down to earth applications. We have shown that the fragile aerogel network can be cross-linked with a di-isocyanate via amine decorated surfaces to form a conformal coating. (3) This coating reinforces the neck regions between secondary silica particles and significantly strengthens the aerogels with only a small effect on density or porosity. Scheme 1 depicts the cross-linking reaction with the di-isocyanate and exhibits the stages that result in polymer cross-linked aerogel monoliths.

  5. New solid-state sensing materials for gaseous dimethylcadmium, di- iso-propyltelluride and dimethylmercury

    NASA Astrophysics Data System (ADS)

    Pardoe, Jennifer A. J.; Cole-Hamilton, David. J.; Hails, Janet E.

    2005-01-01

    Simple solid-state colorimetric sensors for precursors used in and toxic by-products of metal organic vapour-phase epitaxy (MOVPE) of mercury cadmium telluride (MCT) are described. 2,2'-Bipyridine and its commercially available 4,4'-dimethyl-, 5,5'-dimethyl- and 4,4'-di- tert-butyl-dialkyl derivatives have been found to change colour from white or off-white to yellow in the presence of dimethylcadmium at concentrations as low as 13 ppm. The red form of mercury(II) iodide has been tested in both hydrogen and helium gas streams and found to change colour to yellow or white in the presence of gaseous di- iso-propyltelluride at concentrations as low as 1.5 ppm. This form of mercury(II) iodide also reacts photochemically with Me 2Hg in a helium or hydrogen gas stream down to a concentration of 37 ppm.

  6. Contribution of di-SIA to mass transport in Fe-Cr alloys

    NASA Astrophysics Data System (ADS)

    Ryabov, V. A.; Pechenkin, V. A.; Molodtsov, V. L.; Terentyev, D.

    2016-04-01

    Molecular dynamics simulations have been performed to study the diffusion characteristics of di-self interstitial atom (di-SIA) in BCC Fe-Cr alloys and corresponding mass transport of Fe and Cratoms in the temperature range 600-1000 K in the alloys with Cr content 5-25 at%, which is relevant for ferritic/martensitic steels. An original treatment is proposed in this work to account for a mixed migration mode composed of the diffusion of the cluster itself and break-up into a pair of independent SIAs. The ratio of self-diffusion coefficients of Cr and Fe is found to exceed unity in Fe-5Cr and Fe-10Cr alloys, which implies that under cascade-producing damage, 3D-migrating small SIA clusters will effectively contribute to the segregation of Cr to neutral and SIA-preferential sinks, eventually causing radiation induced segregation.

  7. On-line process analysis innovation: DiComp (tm) shunting dielectric sensor technology

    NASA Technical Reports Server (NTRS)

    Davis, Craig R.; Waldman, Frank A.

    1993-01-01

    The DiComp Shunting Dielectric Sensor (SDS) is a new patent-pending technology developed under the Small Business Innovation Research Program (SBIR) for NASA's Kennedy Space Center. The incorporation of a shunt electrode into a conventional fringing field dielectric sensor makes the SDS uniquely sensitive to changes in material dielectric properties in the KHz to MHz range which were previously detectable only at GHz measurement frequencies. The initial NASA application of the SDS for Nutrient Delivery Control has demonstrated SDS capabilities for thickness and concentration measurement of Hoagland nutrient solutions. The commercial introduction of DiComp SDS technology for concentration and percent solids measurements in dispersions, emulsions and solutions represents a new technology for process measurements for liquids in a variety of industries.

  8. Properties of the material of interphase formations based on lanthanide Di-(2-ethylhexyl)phosphate

    NASA Astrophysics Data System (ADS)

    Golubina, E. N.; Kizim, N. F.; Chekmarev, A. M.

    2014-09-01

    The structural, optical, and electrical properties of the material of interphase formations arising spontaneously in the interface region of an extraction system consisting of an aqueous solution of a rare-earth element (REE) salt (a solution of di-(2-ethylhexyl)phosphoric acid (D2EHPA) in an organic solvent) are investigated. The structure of lanthanide di-(2-ethylhexyl)phosphate is determined and its lattice constants are estimated. It is shown that the electric conductivity and optical density of the material of interphase formations transferred onto a glass plate correlate with the accumulation of REEs in the interfacial layer of the extraction system. The difference between the properties of the material of interphase formations based on REEs of the yttrium and cerium subgroups is established.

  9. On-line process analysis innovation: DiComp (tm) shunting dielectric sensor technology

    NASA Astrophysics Data System (ADS)

    Davis, Craig R.; Waldman, Frank A.

    1993-02-01

    The DiComp Shunting Dielectric Sensor (SDS) is a new patent-pending technology developed under the Small Business Innovation Research Program (SBIR) for NASA's Kennedy Space Center. The incorporation of a shunt electrode into a conventional fringing field dielectric sensor makes the SDS uniquely sensitive to changes in material dielectric properties in the KHz to MHz range which were previously detectable only at GHz measurement frequencies. The initial NASA application of the SDS for Nutrient Delivery Control has demonstrated SDS capabilities for thickness and concentration measurement of Hoagland nutrient solutions. The commercial introduction of DiComp SDS technology for concentration and percent solids measurements in dispersions, emulsions and solutions represents a new technology for process measurements for liquids in a variety of industries.

  10. Chamber studies on mass-transfer of di(2-ethylhexyl)phthalate (DEHP) and di- n-butylphthalate (DnBP) from emission sources into house dust

    NASA Astrophysics Data System (ADS)

    Schripp, Tobias; Fauck, Christian; Salthammer, Tunga

    2010-08-01

    For a number of phthalates and especially for di(2-ethylhexyl)phthalate (DEHP), surprisingly high house dust concentrations are reported in the literature. Therefore, the uptake of the most prominent compounds DEHP and di- n-butylphthalate (DnBP) from plasticized indoor materials into house dust samples of different organic content has been experimentally determined. The experiments have been performed within 45 days which is sufficient for the more volatile phthalate (DnBP) to reach equilibrium conditions. DnBP reaches considerably higher concentrations in the chamber air compared to real room measurements and, thus, also elevated dust concentrations. In contrast, the mass transfer of DEHP in the dust via the gas phase was significantly lower. However, small chamber experiments showed elevated mass transfer of DEHP in case of direct contact between emission source and sink. This aspect is experimentally determined using an plasticized PVC polymer with and without direct contact to house dust. A transfer into the dust could be observed in dependence of the initial concentration in the material. However, the results do not allow the differentiation between the two uptake mechanisms via capillary forces and contact to the material's boundary layer. The results illustrate that the reasons for elevated DEHP concentrations in dust indoors can be traced back to direct contact of source and sink, abrasion from the source, and transport via airborne particles.

  11. Pharmacokinetic Study of Di-Phenyl-Di-(2,4-Difluobenzohydroxamato)Tin(IV): Novel Metal-Based Complex with Promising Antitumor Potential

    PubMed Central

    Li, Yunlan; Gao, Zhuyan; Guo, Pu; Li, Qingshan

    2012-01-01

    Di-phenyl-di-(2,4-difluobenzohydroxamato)tin(IV)(DPDFT), a new metal-based arylhydroxamate antitumor complex, showed high in vivo and in vitro antitumor activity with relative low toxicity, but no data was reported regarding its pharmacokinetics and dependent toxicity. In this paper, a rapid, sensitive, and reproducible HPLC method in vivo using Diamonsil ODS column with a mixture of methanol and phosphoric acid in water (30 : 70, V/V, pH 3.0) as mobile phase was developed and validated for the determination of DPDFT. The plasma was deproteinized with methanol that contained acetanilide as the internal standard (I.S.). The photodiode array detector was set at a wavelength of 228 nm at room temperature and a linear curve over the concentration range 0.1~25 μg·mL−1 (r = 0.9993) was obtained. The method was used to determine the concentration-time profiles for DPDFT in the plasma after single intravenous administration with doses of 5, 10, 15 mg·kg−1 to rats. The pharmacokinetics parameter calculations and modeling were carried out using the 3p97 software. The results showed that the concentration-time curves of DPDFT in rat plasma could be fitted to two-compartment model. PMID:22400014

  12. Assessing differences in toxicity and teratogenicity of three phthalates, Diethyl phthalate, Di-n-propyl phthalate, and Di-n-butyl phthalate, using Xenopus laevis embryos.

    PubMed

    Gardner, Steven T; Wood, Andrew T; Lester, Rachel; Onkst, Paitra E; Burnham, Nathaniel; Perygin, Donna H; Rayburn, James

    2016-01-01

    Phthalates, compounds used to add flexibility to plastics, are ubiquitous in the environment. In particular, the diethyl (DEP), di-n-propyl (DnPP), and di-n-butyl (DBP) phthalates were found to exert detrimental effects in both mammalian and non-mammalian studies, with toxic effects varying according to alkyl chain length. Embryos of Xenopus laevis, the African clawed frog, have been used to assess toxicity and teratogenicity of several compounds and serves as a model for assessing adverse and teratogenic effects of ortho-phthalate esters. The purpose of this study was to develop a model for comparison of developmentally toxic effects of ortho-phthalate esters using Xenopus embryos. In this study developing Xenopus laevis embryos were exposed to increasing concentrations of DEP, DnPP, and DBP using the 96-h Frog Embryo Teratogenesis Assay-Xenopus (FETAX), with 96-h lethal concentrations, effective concentrations to induce malformations, teratogenic indices, and concentrations to inhibit growth determined. DEP, DnPP, and DBP showed enhanced toxicity with increasing ester length. Developing Xenopus laevis exposed to DEP, DnPP, and DBP showed similar malformations that also occurred at lower concentrations with increasing alkyl chain length. Teratogenic risk did not change markedly with alkyl chain length, with data showing only DBP to be teratogenic. PMID:26730679

  13. Synthesis and DFT calculation of a novel 5,17-di(2-antracenylazo)-25,27-di(ethoxycarbonylmethoxy)-26,28-dihydroxycalix[4]arene.

    PubMed

    Bayrakdar, A; Kart, H H; Elcin, S; Deligoz, H; Karabacak, M

    2015-02-01

    In this study, 5,17-di(2-antracenylazo)-25,27-di(ethoxycarbonylmethoxy)-26,28-dihydroxycalix[4]arene has been synthesized from 2-aminoantracene and 25,27-dihydroxy-26,28-diethylacetate calix[4]arene. In order to identify the molecular structure and vibrational features of the prepared azocalix[4]arene, FT-IR and (1)H NMR spectral data have been used. FT-IR spectrum of the studied molecule is recorded in the region 4000-400 cm(-1). (1)H NMR spectrum is recorded for 0.1-0.2 M solutions in DMSO-d6 solution. The molecular geometry, infrared spectrum are calculated by the density functional method employing B3LYP level with different basis sets, including 6-31G(d) and LanL2DZ. The chemical shifts calculation for (1)H NMR of the title molecule is calculated by using by Gauge-Invariant Atomic Orbital method by utilizing the same basis sets. The total density of state, the partial density of state and the overlap population density of state diagram analysis are done via GaussSum 3.0 program. Frontier molecular orbital (HOMO-LUMO) and molecular electrostatic potential surface on the title molecule are carried out for various intramolecular interactions that are responsible for the stabilization of the molecule. The experimental results and theoretical calculations have been compared, and they are found to be in good agreement. PMID:25448961

  14. Comparative study of HEPA filter efficiencies when challenged with thermal- and air-jet-generated di-2-ethylhexyl sebecate, di-2-ethylhexyl phthalate, and sodium chloride

    SciTech Connect

    Kerschner, H.F. III; Ettinger, H.J.; DeField, J.D.; Beckman, R.

    1984-12-01

    Respirators fitted with high-efficiency particulate (HEPA) cartridge filters are designed to remove dust, fumes, mists, and airborne particulate radionuclides. If these filters are to be reused, a Quality Assurance (QA) program must be established to ensure that filter efficiency remains greater than 99.97%. The standard method for performing QA testing is to challenge the filter with a thermally generated aerosol of 0.3-..mu..m-diam di-2-ethylhexyl phthalate (DEHP). Because of potential toxicological and other problems associated with the use of monodisperse DEHP, an investigation to study measured filter efficiencies on a HEPA respirator filter population, using several recommended replacement aerosols, has been conducted. Aerosols compared in this study were thermally generated di-2-ethylhexyl sebecate (DEHS), thermally generated DEHP, air-jet-generated DEHS, and air-jet-generated salt (NaCl). The study also focused on determining compatibility for parallel use of aerosols generated for respirator-fit testing for use in QA filter testing. Results indicate that a polydisperse air-jet-generated aerosol of DEHS can substitute for thermally generated DEHP as a method of providing QA testing of HEPA respirator filters and that equipment used in the study designed for respirator quantitative-fit testing can easily be modified to perform this function. 30 refs., 28 figs., 11 tabs.

  15. Synthesis and DFT calculation of a novel 5,17-di(2-antracenylazo)-25,27-di(ethoxycarbonylmethoxy)-26,28-dihydroxycalix[4]arene

    NASA Astrophysics Data System (ADS)

    Bayrakdar, A.; Kart, H. H.; Elcin, S.; Deligoz, H.; Karabacak, M.

    2015-02-01

    In this study, 5,17-di(2-antracenylazo)-25,27-di(ethoxycarbonylmethoxy)-26,28-dihydroxycalix[4]arene has been synthesized from 2-aminoantracene and 25,27-dihydroxy-26,28-diethylacetate calix[4]arene. In order to identify the molecular structure and vibrational features of the prepared azocalix[4]arene, FT-IR and 1H NMR spectral data have been used. FT-IR spectrum of the studied molecule is recorded in the region 4000-400 cm-1. 1H NMR spectrum is recorded for 0.1-0.2 M solutions in DMSO-d6 solution. The molecular geometry, infrared spectrum are calculated by the density functional method employing B3LYP level with different basis sets, including 6-31G(d) and LanL2DZ. The chemical shifts calculation for 1H NMR of the title molecule is calculated by using by Gauge-Invariant Atomic Orbital method by utilizing the same basis sets. The total density of state, the partial density of state and the overlap population density of state diagram analysis are done via GaussSum 3.0 program. Frontier molecular orbital (HOMO-LUMO) and molecular electrostatic potential surface on the title molecule are carried out for various intramolecular interactions that are responsible for the stabilization of the molecule. The experimental results and theoretical calculations have been compared, and they are found to be in good agreement.

  16. Pharmacokinetic Study of Di-Phenyl-Di-(2,4-Difluobenzohydroxamato)Tin(IV): Novel Metal-Based Complex with Promising Antitumor Potential.

    PubMed

    Li, Yunlan; Gao, Zhuyan; Guo, Pu; Li, Qingshan

    2012-01-01

    Di-phenyl-di-(2,4-difluobenzohydroxamato)tin(IV)(DPDFT), a new metal-based arylhydroxamate antitumor complex, showed high in vivo and in vitro antitumor activity with relative low toxicity, but no data was reported regarding its pharmacokinetics and dependent toxicity. In this paper, a rapid, sensitive, and reproducible HPLC method in vivo using Diamonsil ODS column with a mixture of methanol and phosphoric acid in water (30 : 70, V/V, pH 3.0) as mobile phase was developed and validated for the determination of DPDFT. The plasma was deproteinized with methanol that contained acetanilide as the internal standard (I.S.). The photodiode array detector was set at a wavelength of 228 nm at room temperature and a linear curve over the concentration range 0.1~25 μg·mL(-1) (r = 0.9993) was obtained. The method was used to determine the concentration-time profiles for DPDFT in the plasma after single intravenous administration with doses of 5, 10, 15 mg·kg(-1) to rats. The pharmacokinetics parameter calculations and modeling were carried out using the 3p97 software. The results showed that the concentration-time curves of DPDFT in rat plasma could be fitted to two-compartment model. PMID:22400014

  17. A Minimal Threshold of c-di-GMP Is Essential for Fruiting Body Formation and Sporulation in Myxococcus xanthus.

    PubMed

    Skotnicka, Dorota; Smaldone, Gregory T; Petters, Tobias; Trampari, Eleftheria; Liang, Jennifer; Kaever, Volkhard; Malone, Jacob G; Singer, Mitchell; Søgaard-Andersen, Lotte

    2016-05-01

    Generally, the second messenger bis-(3'-5')-cyclic dimeric GMP (c-di-GMP) regulates the switch between motile and sessile lifestyles in bacteria. Here, we show that c-di-GMP is an essential regulator of multicellular development in the social bacterium Myxococcus xanthus. In response to starvation, M. xanthus initiates a developmental program that culminates in formation of spore-filled fruiting bodies. We show that c-di-GMP accumulates at elevated levels during development and that this increase is essential for completion of development whereas excess c-di-GMP does not interfere with development. MXAN3735 (renamed DmxB) is identified as a diguanylate cyclase that only functions during development and is responsible for this increased c-di-GMP accumulation. DmxB synthesis is induced in response to starvation, thereby restricting DmxB activity to development. DmxB is essential for development and functions downstream of the Dif chemosensory system to stimulate exopolysaccharide accumulation by inducing transcription of a subset of the genes encoding proteins involved in exopolysaccharide synthesis. The developmental defects in the dmxB mutant are non-cell autonomous and rescued by co-development with a strain proficient in exopolysaccharide synthesis, suggesting reduced exopolysaccharide accumulation as the causative defect in this mutant. The NtrC-like transcriptional regulator EpsI/Nla24, which is required for exopolysaccharide accumulation, is identified as a c-di-GMP receptor, and thus a putative target for DmxB generated c-di-GMP. Because DmxB can be-at least partially-functionally replaced by a heterologous diguanylate cyclase, these results altogether suggest a model in which a minimum threshold level of c-di-GMP is essential for the successful completion of multicellular development in M. xanthus. PMID:27214040

  18. Mechanistic insights into c-di-GMP-dependent control of the biofilm regulator FleQ from Pseudomonas aeruginosa.

    PubMed

    Matsuyama, Bruno Y; Krasteva, Petya V; Baraquet, Claudine; Harwood, Caroline S; Sondermann, Holger; Navarro, Marcos V A S

    2016-01-12

    Bacterial biofilm formation during chronic infections confers increased fitness, antibiotic tolerance, and cytotoxicity. In many pathogens, the transition from a planktonic lifestyle to collaborative, sessile biofilms represents a regulated process orchestrated by the intracellular second-messenger c-di-GMP. A main effector for c-di-GMP signaling in the opportunistic pathogen Pseudomonas aeruginosa is the transcription regulator FleQ. FleQ is a bacterial enhancer-binding protein (bEBP) with a central AAA+ ATPase σ(54)-interaction domain, flanked by a C-terminal helix-turn-helix DNA-binding motif and a divergent N-terminal receiver domain. Together with a second ATPase, FleN, FleQ regulates the expression of flagellar and exopolysaccharide biosynthesis genes in response to cellular c-di-GMP. Here we report structural and functional data that reveal an unexpected mode of c-di-GMP recognition that is associated with major conformational rearrangements in FleQ. Crystal structures of FleQ's AAA+ ATPase domain in its apo-state or bound to ADP or ATP-γ-S show conformations reminiscent of the activated ring-shaped assemblies of other bEBPs. As revealed by the structure of c-di-GMP-complexed FleQ, the second messenger interacts with the AAA+ ATPase domain at a site distinct from the ATP binding pocket. c-di-GMP interaction leads to active site obstruction, hexameric ring destabilization, and discrete quaternary structure transitions. Solution and cell-based studies confirm coupling of the ATPase active site and c-di-GMP binding, as well as the functional significance of crystallographic interprotomer interfaces. Taken together, our data offer unprecedented insight into conserved regulatory mechanisms of gene expression under direct c-di-GMP control via FleQ and FleQ-like bEBPs. PMID:26712005

  19. The Cyclic AMP-Vfr Signaling Pathway in Pseudomonas aeruginosa Is Inhibited by Cyclic Di-GMP

    PubMed Central

    Almblad, Henrik; Harrison, Joe J.; Rybtke, Morten; Groizeleau, Julie; Givskov, Michael; Parsek, Matthew R.

    2015-01-01

    ABSTRACT The opportunistic human pathogen Pseudomonas aeruginosa expresses numerous acute virulence factors in the initial phase of infection, and during long-term colonization it undergoes adaptations that optimize survival in the human host. Adaptive changes that often occur during chronic infection give rise to rugose small colony variants (RSCVs), which are hyper-biofilm-forming mutants that commonly possess mutations that increase production of the biofilm-promoting secondary messenger cyclic di-GMP (c-di-GMP). We show that RSCVs display a decreased production of acute virulence factors as a direct result of elevated c-di-GMP content. Overproduction of c-di-GMP causes a decrease in the transcription of virulence factor genes that are regulated by the global virulence regulator Vfr. The low level of Vfr-dependent transcription is caused by a low level of its coactivator, cyclic AMP (cAMP), which is decreased in response to a high level of c-di-GMP. Mutations that cause reversion of the RSCV phenotype concomitantly reactivate Vfr-cAMP signaling. Attempts to uncover the mechanism underlying the observed c-di-GMP-mediated lowering of cAMP content provided evidence that it is not caused by inhibition of adenylate cyclase production or activity and that it is not caused by activation of cAMP phosphodiesterase activity. In addition to the studies of the RSCVs, we present evidence that the deeper layers of wild-type P. aeruginosa biofilms have high c-di-GMP levels and low cAMP levels. IMPORTANCE Our work suggests that cross talk between c-di-GMP and cAMP signaling pathways results in downregulation of acute virulence factors in P. aeruginosa biofilm infections. Knowledge about this cross-regulation adds to our understanding of virulence traits and immune evasion by P. aeruginosa in chronic infections and may provide new approaches to eradicate biofilm infections. PMID:25897033

  20. Mechanistic insights into c-di-GMP–dependent control of the biofilm regulator FleQ from Pseudomonas aeruginosa

    PubMed Central

    Matsuyama, Bruno Y.; Krasteva, Petya V.; Baraquet, Claudine; Harwood, Caroline S.; Sondermann, Holger; Navarro, Marcos V. A. S.

    2016-01-01

    Bacterial biofilm formation during chronic infections confers increased fitness, antibiotic tolerance, and cytotoxicity. In many pathogens, the transition from a planktonic lifestyle to collaborative, sessile biofilms represents a regulated process orchestrated by the intracellular second-messenger c-di-GMP. A main effector for c-di-GMP signaling in the opportunistic pathogen Pseudomonas aeruginosa is the transcription regulator FleQ. FleQ is a bacterial enhancer-binding protein (bEBP) with a central AAA+ ATPase σ54-interaction domain, flanked by a C-terminal helix-turn-helix DNA-binding motif and a divergent N-terminal receiver domain. Together with a second ATPase, FleN, FleQ regulates the expression of flagellar and exopolysaccharide biosynthesis genes in response to cellular c-di-GMP. Here we report structural and functional data that reveal an unexpected mode of c-di-GMP recognition that is associated with major conformational rearrangements in FleQ. Crystal structures of FleQ’s AAA+ ATPase domain in its apo-state or bound to ADP or ATP-γ-S show conformations reminiscent of the activated ring-shaped assemblies of other bEBPs. As revealed by the structure of c-di-GMP–complexed FleQ, the second messenger interacts with the AAA+ ATPase domain at a site distinct from the ATP binding pocket. c-di-GMP interaction leads to active site obstruction, hexameric ring destabilization, and discrete quaternary structure transitions. Solution and cell-based studies confirm coupling of the ATPase active site and c-di-GMP binding, as well as the functional significance of crystallographic interprotomer interfaces. Taken together, our data offer unprecedented insight into conserved regulatory mechanisms of gene expression under direct c-di-GMP control via FleQ and FleQ-like bEBPs. PMID:26712005

  1. Type IV pilus assembly in Pseudomonas aeruginosa over a broad range of cyclic di-GMP concentrations.

    PubMed

    Jain, Ruchi; Behrens, Anna-Janina; Kaever, Volkhard; Kazmierczak, Barbara I

    2012-08-01

    Pseudomonas aeruginosa is a Gram-negative, opportunistic pathogen that utilizes polar type IV pili (T4P) for twitching motility and adhesion in the environment and during infection. Pilus assembly requires FimX, a GGDEF/EAL domain protein that binds and hydrolyzes cyclic di-GMP (c-di-GMP). Bacteria lacking FimX are deficient in twitching motility and microcolony formation. We carried out an extragenic suppressor screen in PA103ΔfimX bacteria to identify additional regulators of pilus assembly. Multiple suppressor mutations were mapped to PA0171, PA1121 (yfiR), and PA3703 (wspF), three genes previously associated with small-colony-variant phenotypes. Multiple independent techniques confirmed that suppressors assembled functional surface pili, though at both polar and nonpolar sites. Whole-cell c-di-GMP levels were elevated in suppressor strains, in agreement with previous studies that had shown that the disrupted genes encoded negative regulators of diguanylate cyclases. Overexpression of the regulated diguanylate cyclases was sufficient to suppress the ΔfimX pilus assembly defect, as was overexpression of an unrelated diguanylate cyclase from Caulobacter crescentus. Furthermore, under natural conditions of high c-di-GMP, PA103ΔfimX formed robust biofilms that showed T4P staining and were structurally distinct from those formed by nonpiliated bacteria. These results are the first demonstration that P. aeruginosa assembles a surface organelle, type IV pili, over a broad range of c-di-GMP concentrations. Assembly of pili at low c-di-GMP concentrations requires a polarly localized c-di-GMP binding protein and phosphodiesterase, FimX; this requirement for FimX is bypassed at high c-di-GMP concentrations. Thus, P. aeruginosa can assemble the same surface organelle in distinct ways for motility or adhesion under very different environmental conditions. PMID:22685276

  2. Development and evaluation of systems for controlling parallel high di/dt thyratrons

    SciTech Connect

    Litton. A.; McDuff, G.

    1982-01-01

    Increasing numbers of high power, high repetition rate applications dictate the use or thyratrons in multiple of hard parallel configurations to achieve the required rate of current rise, di/dt. This in turn demands the development of systems to control parallel thyratron commutation with nanosecond accuracy. Such systems must be capable of real-time, fully-automated control in multi-kilohertz applications while still remaining cost effective. This paper describes the evolution of such a control methodology and system.

  3. Strength and nature of hydrogen bonding interactions in mono- and di-hydrated formamide complexes.

    PubMed

    Angelina, Emilio L; Peruchena, Nélida M

    2011-05-12

    In this work, mono- and di-hydrated complexes of the formamide were studied. The calculations were performed at the MP2/6-311++G(d,p) level of approximation. The atoms in molecules theory (AIM), based on the topological properties of the electronic density distribution, was used to characterize the different types of bonds. The analysis of the hydrogen bonds (H-bonds) in the most stable mono- and di-hydrated formamide complexes shows a mutual reinforcement of the interactions, and some of these complexes can be considered as "bifunctional hydrogen bonding hydration complexes". In addition, we analyzed how the strength and the nature of the interactions, in mono-hydrated complexes, are modified by the presence of a second water molecule in di-hydrated formamide complexes. Structural changes, cooperativity, and electron density redistributions demonstrate that the H-bonds are stronger in the di-hydrated complexes than in the corresponding mono-hydrated complexes, wherein the σ- and π-electron delocalization were found. To explain the nature of such interactions, we carried out the atoms in molecules theory in conjunction with reduced variational space self-consistent field (RVS) decomposition analysis. On the basis of the local Virial theorem, the characteristics of the local electron energy density components at the bond critical points (BCPs) (the 1/4∇ (2)ρ(b) component of electron energy density and the kinetic energy density) were analyzed. These parameters were used in conjunction with the electron density and the Laplacian of the electron density to analyze the characteristics of the interactions. The analysis of the interaction energy components for the systems considered indicates that the strengthening of the hydrogen bonds is manifested by an increased contribution of the electrostatic energy component represented by the kinetic energy density at the BCP. PMID:21506592

  4. DiPerna-Lions Flow for Relativistic Particles in an Electromagnetic Field

    NASA Astrophysics Data System (ADS)

    Jabin, P.-E.; Masmoudi, N.

    2015-09-01

    We show the existence and uniqueness of a DiPerna-Lions flow for relativistic particles subject to a Lorentz force in an electromagnetic field. The electric and magnetic fields solve the linear Maxwell system in the vacuum but for singular initial conditions which are only in the physical energy space. As the corresponding force field is only in L 2, we have to perform a careful analysis of the cancellations over a trajectory.

  5. DiAs User Interface: A Patient-Centric Interface for Mobile Artificial Pancreas Systems

    PubMed Central

    Keith-Hynes, Patrick; Guerlain, Stephanie; Mize, Benton; Hughes-Karvetski, Colleen; Khan, Momin; McElwee-Malloy, Molly; Kovatchev, Boris P.

    2013-01-01

    Background Recent in-hospital studies of artificial pancreas (AP) systems have shown promising results in improving glycemic control in patients with type 1 diabetes mellitus. The next logical step in AP development is to conduct transitional outpatient clinical trials with a mobile system that is controlled by the patient. In this article, we present the user interface (UI) of the Diabetes Assistant (DiAs), an experimental smartphone-based mobile AP system, and describe the reactions of a round of focus groups to the UI. This work is an initial inquiry involving a relatively small number of potential users, many of whom had never seen an AP system before, and the results should be understood in that light. Methods We began by considering how the UI of an AP system could be designed to make use of the familiar touch-based graphical UI of a consumer smartphone. After developing a working prototype UI, we enlisted a human factors specialist to perform a heuristic expert analysis. Next we conducted a formative evaluation of the UI through a series of three focus groups with N = 13 potential end users as participants. The UI was modified based upon the results of these studies, and the resulting DiAs system was used in transitional outpatient AP studies of adults in the United States and Europe. Results The DiAs UI was modified based on focus group feedback from potential users. The DiAs was subsequently used in JDRF- and AP@Home-sponsored transitional outpatient AP studies in the United States and Europe by 40 subjects for 2400 h with no adverse events. Conclusions Adult patients with type 1 diabetes mellitus are able to control an AP system successfully using a patient-centric UI on a commercial smartphone in a transitional outpatient environment. PMID:24351168

  6. Characterization and biological effects of di-hydroxylated compounds deriving from the lipoxygenation of ALA

    PubMed Central

    Liu, Miao; Chen, Ping; Véricel, Evelyne; Lelli, Moreno; Béguin, Laetitia; Lagarde, Michel; Guichardant, Michel

    2013-01-01

    We have recently described a di-hydroxylated compound called protectin DX (PDX) which derives from docosahexaenoic acid (DHA) by double lipoxygenation. PDX exhibits anti-aggregatory and anti-inflammatory properties, that are also exhibited by similar molecules, called poxytrins, which possess the same E,Z,E conjugated triene geometry, and are synthesized from other polyunsaturated fatty acids with 22 or 20 carbons. Here we present new biological activities of di-hydroxylated metabolites deriving from α-linolenic acid (18:3n-3) treated by soybean 15-lipoxygenase (sLOX). We show that 18:3n-3 is converted by sLOX into mainly 13(S)-OH-18:3 after reduction of the hydroperoxide product. But surprisingly, and in contrast to DHA which is metabolized into only one di-hydroxylated compound, 18:3n-3 leads to four di-hydroxylated fatty acid isomers. We report here the complete characterization of these compounds using high field NMR and GC-MS techniques, and some of their biological activities. These compounds are: 9(R),16(S)-dihydroxy-10E,12E,14E-octadecatrienoic acid, 9(S),16(S)-dihydroxy-10E,12E,14E-octadecatrienoic acid, 9(S),16(S)-dihydroxy-10E,12Z,14E-octadecatrienoic acid, and 9(R),16(S)-dihydroxy-10E,12Z,14E-octadecatrienoic acid. They can also be synthesized by the human recombinant 15-lipoxygenase (type 2). Their inhibitory effect on blood platelet and anti-inflammatory properties were compared with those already reported for PDX. PMID:23740966

  7. Mono-, di-, and tri- tert-butyl ethers of glycerol . A molecular spectroscopic study

    NASA Astrophysics Data System (ADS)

    Jamróz, Małgorzata E.; Jarosz, Małgorzata; Witowska-Jarosz, Janina; Bednarek, Elżbieta; Tęcza, Witold; Jamróz, Michał H.; Dobrowolski, Jan Cz.; Kijeński, Jacek

    2007-07-01

    MS, NMR, IR and Raman molecular spectroscopy techniques were applied to characterize 3- tert-butoxy-propane-1,2-diol, 1,3-di- tert-butoxy-propan-2-ol, and 1,2,3-tri- tert-butoxy-propane. These ethers are the main products of glycerol etherification reaction and are excellent oxygen additives for diesel fuel. Computational DFT/ B3LYP/6-31G ** studies were performed to support and rationalize both vibrational spectroscopy analysis and the isomer ratio.

  8. A Bacterial Hemerythrin Domain Regulates Activity of a Vibrio cholerae Di-Guanylate Cyclase

    PubMed Central

    Schaller, Ruth A.; Ali, Syed Khalid; Klose, Karl E.; Kurtz, Donald M.

    2012-01-01

    The first demonstrated example of a regulatory function for a bacterial hemerythrin (Bhr) domain is reported. Bhrs have a characteristic sequence motif providing ligand residues for a type of non-heme diiron site that is known to bind O2 and undergo autoxidation. The amino acid sequence encoded by the gene, VC1216, from Vibrio cholerae O1 biovar El Tor str. N16961 contains an N-terminal Bhr domain connected to a C-terminal domain characteristic of bacterial di-guanylate cyclases (DGCs) that catalyze formation of cyclic di-(3′,5′)-guanosine monophosphate (c-di-GMP) from GTP. This protein, Vc Bhr-DGC, was found to contain two tightly bound non-heme iron atoms per protein monomer. The as-isolated protein showed the spectroscopic signatures of oxo/dicarboxylato-bridged non-heme diferric sites of previously characterized Bhr domains. The diiron site was capable of cycling between diferric and diferrous forms, the latter of which was stable only under anaerobic conditions, undergoing rapid autoxidation upon exposure to air. Vc Bhr-DGC showed approximately 10-times higher DGC activity in the diferrous relative to the diferric form. The level of intracellular c-di-GMP is known to regulate biofilm formation in Vibrio cholerae. The higher DGC activity of the diferrous Vc Bhr-DGC is consistent with induction of biofilm formation in low dioxygen environments. The non-heme diiron cofactor in the Bhr domain thus represents an alternative to heme or flavin for redox and/or diatomic gas sensing and regulation of DGC activity. PMID:23057727

  9. USSAERO version D computer program development using ANSI standard FORTRAN 77 and DI-3000 graphics

    NASA Technical Reports Server (NTRS)

    Wiese, M. R.

    1986-01-01

    The D version of the Unified Subsonic Supersonic Aerodynamic Analysis (USSAERO) program is the result of numerous modifications and enhancements to the B01 version. These changes include conversion to ANSI standard FORTRAN 77; use of the DI-3000 graphics package; removal of the overlay structure; a revised input format; the addition of an input data analysis routine; and increasing the number of aeronautical components allowed.

  10. Crystal structure of 4,4-dibutyl-2-phenyl-3,4-di-hydro-quinazoline.

    PubMed

    El-Hiti, Gamal A; Smith, Keith; Hegazy, Amany S; Alshammari, Mohammed B; Kariuki, Benson M

    2014-10-01

    In the title compound, C22H28N2, the dihedral angle between the planes of the phenyl ring and the di-hydro-quinazoline ring system (r.m.s. deviation = 0.030 Å) is 24.95 (7)° and both n-butane chains assume all-trans conformations. In the crystal, N-H⋯N hydrogen bonds link the mol-ecules into C(4) chains propagating in the [001] direction. PMID:25484693

  11. A di- and tripeptide transport system can supply Listeria monocytogenes Scott A with amino acids essential for growth.

    PubMed Central

    Verheul, A; Hagting, A; Amezaga, M R; Booth, I R; Rombouts, F M; Abee, T

    1995-01-01

    Listeria monocytogenes takes up di- and tripeptides via a proton motive force-dependent carrier protein. This peptide transport system resembles the recently cloned and sequenced secondary di- and tripeptide transport system of Lactococcus lactis (A. Hagting, E. R. S. Kunji, K. J. Leenhouts, B. Poolman, and W. N. Konings, J. Biol. Chem. 269:11391-11399, 1994). The peptide permease of L. monocytogenes has a broad substrate specificity and allows transport of the nonpeptide substrate 5-aminolevulinic acid, the toxic di- and tripeptide analogs, alanyl-beta-chloroalanine and alanyl-alanyl-beta-chloroalanine, and various di- and tripeptides. No extracellular peptide hydrolysis was detected, indicating that peptides are hydrolyzed after being transported into the cell. Indeed, peptidase activities in response to various synthetic substrates were detected in cell extracts obtained from L. monocytogenes cells grown in brain heart infusion broth or defined medium. The di- and tripeptide permease can supply L. monocytogenes with essential amino acids for growth and might contribute to growth of this pathogen in various foods where peptides are supplied by proteolytic activity of other microorganisms present in these foods. Possible roles of this di- and tripeptide transport system in the osmoregulation and virulence of L. monocytogenes are discussed. PMID:7887604

  12. C-di-GMP regulates Pseudomonas aeruginosa stress response to tellurite during both planktonic and biofilm modes of growth

    PubMed Central

    Chua, Song Lin; Sivakumar, Krishnakumar; Rybtke, Morten; Yuan, Mingjun; Andersen, Jens Bo; Nielsen, Thomas E.; Givskov, Michael; Tolker-Nielsen, Tim; Cao, Bin; Kjelleberg, Staffan; Yang, Liang

    2015-01-01

    Stress response plays an important role on microbial adaptation under hostile environmental conditions. It is generally unclear how the signaling transduction pathway mediates a stress response in planktonic and biofilm modes of microbial communities simultaneously. Here, we showed that metalloid tellurite (TeO32–) exposure induced the intracellular content of the secondary messenger cyclic di-GMP (c-di-GMP) of Pseudomonas aeruginosa. Two diguanylate cyclases (DGCs), SadC and SiaD, were responsible for the increased intracellular content of c-di-GMP. Enhanced c-di-GMP levels by TeO32– further increased P. aeruginosa biofilm formation and resistance to TeO32–. P. aeruginosa ΔsadCΔsiaD and PAO1/plac-yhjH mutants with low intracellular c-di-GMP content were more sensitive to TeO32– exposure and had low relative fitness compared to the wild-type PAO1 planktonic and biofilm cultures exposed to TeO32–. Our study provided evidence that c-di-GMP level can play an important role in mediating stress response in microbial communities during both planktonic and biofilm modes of growth. PMID:25992876

  13. Highly efficient enzymatic preparation of c-di-AMP using the diadenylate cyclase DisA from Bacillus thuringiensis.

    PubMed

    Zheng, Cao; Wang, Jieping; Luo, Yunchao; Fu, Yang; Su, Jianmei; He, Jin

    2013-05-10

    Cyclic 3',5'-diadenosine monophosphate (c-di-AMP) is a newly recognized bacterial nucleotide second messenger molecule. In addition, it has been shown to be a potential vaccine adjuvant. Although multiple methods are available for c-di-AMP synthesis, the yields are low and the purification procedures are laborious. Here, we report an enzymatic method for more efficient and economical c-di-AMP synthesis using a diadenylate cyclase DisA from Bacillus thuringiensis BMB 171 (btDisA). After overexpression and purification of btDisA, the enzyme-catalyzed reaction conditions were further investigated. Under the optimum conditions, in which 100mM CHES (pH 9.5) containing 2μM btDisA, 10mM ATP, and 10mM MgCl2 was incubated at 50°C for 4h, a high conversion rate of c-di-AMP was obtained. Coupling this process with HPLC purification and lyophilization yielded 100mg of highly pure c-di-AMP that was harvested in white powder form from a 50mL enzyme-catalyzed reaction system. The protocol is not only directly applicable for preparing abundant amounts of c-di-AMP for extensive biochemical and immunological use, but can also be scaled up to meet the requirements for medical applications. PMID:23608499

  14. Ab-initio study of germanium di-interstitial using a hybrid functional (HSE)

    NASA Astrophysics Data System (ADS)

    Igumbor, E.; Ouma, C. N. M.; Webb, G.; Meyer, W. E.

    2016-01-01

    In this work, we present ab-initio calculation results of Ge di-interstitials (I2(Ge)) in the framework of the density functional theory (DFT) using the Heyd, Scuseria, and Ernzerhof (HSE) hybrid functional. The formation energy, transition levels and minimum energy configurations were obtained for I2(Ge) -2, -1, 0, +1 and +2 charge states. The calculated formation energies show that for all charge states of I2(Ge), the double tetrahedral (T) configuration formed the most stable defect with a binding energy of 1.24 eV in the neutral state. We found the (+2/+1) charge state transition level for the T lying below the conduction band minimum and (+2/+1) for the split[110]-tetrahedral configuration lying deep at 0.41 eV above the valence band maximum. The di-interstitials in Ge exhibited the properties of both shallow and deep donor levels at (+2/+1) within the band gap and depending on the configurations. I2(Ge) gave rise to negative-U, with effective-U values of -0.61 and -1.6 eV in different configurations. We have compared our results with calculations of di-interstitials in silicon and available experimental data.

  15. Microcrystals engineering using assemblies of di-protonated meso-tetraphenylporphine dimers under Zundel cations operation

    NASA Astrophysics Data System (ADS)

    Udal'tsov, Alexander V.

    2015-03-01

    New approach based on the usage of self-organized assemblies of di-protonated meso-tetraphenylporphine (TPP) dimers under Zundel cations action is suggested for the microcrystals engineering. Properties of the assemblies consisting of water and the protonated dimers, as produced in aqueous HCl in the presence of a small concentration of water-soluble organic solvent were investigated by UV-Vis and infrared spectroscopy and atomic force microscopy (AFM) in thin films. The self-organized assemblies consisting of water and di-protonated TPP dimers looked like long rods produced green crystals. These crystals were found by light microscopy. The ordered assembled structures crystallized into thin layers at open air at relative humidity of least 60%. Three acts of the microcrystals engineering actions are needed to obtain the green crystals that are (i) self-assembling of protonated TPP dimers under Zundel cations operation; (ii) generation of pure rod precursor in the di-protonated state and (iii) application of gaseous water to initiate the crystallization in order to Zundel cations action in the surface layer could occur. The size of the green crystals produced by the self-organized assemblies varies within 30-35 μm.

  16. Di- or polysulphide-bound biomarkers in sulphur-rich geomacromolecules as revealed by selective chemolysis

    NASA Astrophysics Data System (ADS)

    Kohnen, Math E. l.; Sinninghe Damst, Jaap S.; Kock-van Dalen, A. c.; Jan, W. De Leeuw

    1991-05-01

    Three types of sulphur-rich high-molecular-weight material in the alkylsulphide, the polar, and the asphaltene fractions isolated from the bitumen of an immature bituminous shale from the Vena del Gesso basin (Italy) were desulphurised using Raney Ni and were treated with MeLi/MeI, a chemical degradation method which cleaves selectively and quantitatively di- or polysulphide linkages. The products formed were characterised by gas chromatography-mass spectrometry. Raney Ni desulphurisation revealed that these S-rich macromolecules are in substantial part composed of sulphur-linked biomarkers with linear, branched, isoprenoid, steroid, hopanoid, and carotenoid carbon skeletons. MeLi/Mel treatment provided evidence that a major part of the total amount of macromolecularly bound biomarkers are linked via di- or polysulphide moieties to the macromolecular network. Since the di- or polysulphide linkages are attached at specific positions of the bound biomarkers it is proposed that they are formed by intermolecular incorporation reactions of HS x- into low-molecular-weight functionalised biological lipids during early diagenesis. The different properties (solubility and molecular weight) of the sulphur-rich macromolecules in the alkylsulphide, the resin, and the asphaltene fractions can be explained simply by differences in degree of sulphur cross-linking.

  17. Fluorescent labeling of dendritic spines in cell cultures with the carbocyanine dye “DiI”

    PubMed Central

    Cheng, Connie; Trzcinski, Olivia; Doering, Laurie C.

    2014-01-01

    Analyzing cell morphology is a key component to understand neuronal function. Several staining techniques have been developed to facilitate the morphological analysis of neurons, including the use of fluorescent markers, such as DiI (1,1′-dioctadecyl-3,3,3′,3′-tetramethylindocarbocyanine perchlorate). DiI is a carbocyanine membrane dye that exhibits enhanced fluorescence upon insertion of its lipophilic hydrocarbon chains into the lipid membrane of cells. The high photostability and prominent fluorescence of the dye serves as an effective means of illuminating cellular architecture in individual neurons, including detailed dendritic arborizations and spines in cell culture and tissue sections. Here, we specifically optimized a simple and reliable method to fluorescently label and visualize dissociated hippocampal neurons using DiI and high-resolution confocal microscopic imaging. With high efficacy, this method accurately labels neuronal and synaptic morphology to permit quantitative analysis of dendritic spines. Accurate imaging techniques of these fine neuronal specializations are vital to the study of their morphology and can help delineate structure-function relationships in the central nervous system. PMID:24847216

  18. Novel Mono-, Di-, and Trimethylornithine Membrane Lipids in Northern Wetland Planctomycetes

    PubMed Central

    Hopmans, Ellen C.; Rijpstra, W. Irene C.; Villanueva, Laura; Dedysh, Svetlana N.; Kulichevskaya, Irina S.; Wienk, Hans; Schoutsen, Frans; Sinninghe Damsté, Jaap S.

    2013-01-01

    Northern peatlands represent a significant global carbon store and commonly originate from Sphagnum moss-dominated wetlands. These ombrotrophic ecosystems are rain fed, resulting in nutrient-poor, acidic conditions. Members of the bacterial phylum Planctomycetes are highly abundant and appear to play an important role in the decomposition of Sphagnum-derived litter in these ecosystems. High-performance liquid chromatography coupled to high-resolution accurate-mass mass spectrometry (HPLC-HRAM/MS) analysis of lipid extracts of four isolated planctomycetes from wetlands of European north Russia revealed novel ornithine membrane lipids (OLs) that are mono-, di-, and trimethylated at the ε-nitrogen position of the ornithine head group. Nuclear magnetic resonance (NMR) analysis of the isolated trimethylornithine lipid confirmed the structural identification. Similar fatty acid distributions between mono-, di-, and trimethylornithine lipids suggest that the three lipid classes are biosynthetically linked, as in the sequential methylation of the terminal nitrogen in phosphatidylethanolamine to produce phosphatidylcholine. The mono-, di-, and trimethylornithine lipids described here represent the first report of methylation of the ornithine head groups in biological membranes. Various bacteria are known to produce OLs under phosphorus limitation or fatty-acid-hydroxylated OLs under thermal or acid stress. The sequential methylation of OLs, leading to a charged choline-like moiety in the trimethylornithine lipid head group, may be an adaptation to provide membrane stability under acidic conditions without the use of scarce phosphate in nutrient-poor ombrotrophic wetlands. PMID:23995937

  19. Di-rhamnolipid is a mosquito pupicidal metabolite from Pseudomonas fluorescens (VCRC B426).

    PubMed

    Prabakaran, G; Hoti, S L; Rao, H Surya Prakash; Vijjapu, Satish

    2015-08-01

    Pseudomonas fluorescens Migula (VCRC B426) produces a secondary metabolite, which was found to be active against pupae of vector mosquitoes namely Culex quinquefasciatus, Anopheles stephensi and Aedes aegypti. The mosquito pupicidal metabolite from P. fluoescens was mass produced and separated by ethyl acetate extraction and purified further by silica gel column chromatography, FPLC, HPLC and TLC. The purified metabolite was characterized by NMR, FT-IR, LC-MS and MALDI-TOF. The FT-IR, (1)H and (13)C NMR results showed that it is a rhamnolipid (di-rhamnolipid). The matrix assisted laser desorption and ionization-time-of-flight spectrum of the sample showed predominant pupicidal component produced by P. fluorescens was the molecule mass of 673.40 Da. Owing to its high toxicity to mosquito pupae, especially Anopheles sp., and Aedes sp., the di-rhamnolipd has potential in the control of the vectors of dengue, chikungunya, yellow fever and malaria. This is the first report of mosquito pupicidal di-rhamnolipid from P. fluorescens. PMID:25912083

  20. High-Resolution Enabled 12-Plex DiLeu Isobaric Tags for Quantitative Proteomics

    PubMed Central

    2015-01-01

    Multiplex isobaric tags (e.g., tandem mass tags (TMT) and isobaric tags for relative and absolute quantification (iTRAQ)) are a valuable tool for high-throughput mass spectrometry based quantitative proteomics. We have developed our own multiplex isobaric tags, DiLeu, that feature quantitative performance on par with commercial offerings but can be readily synthesized in-house as a cost-effective alternative. In this work, we achieve a 3-fold increase in the multiplexing capacity of the DiLeu reagent without increasing structural complexity by exploiting mass defects that arise from selective incorporation of 13C, 15N, and 2H stable isotopes in the reporter group. The inclusion of eight new reporter isotopologues that differ in mass from the existing four reporters by intervals of 6 mDa yields a 12-plex isobaric set that preserves the synthetic simplicity and quantitative performance of the original implementation. We show that the new reporter variants can be baseline-resolved in high-resolution higher-energy C-trap dissociation (HCD) spectra, and we demonstrate accurate 12-plex quantitation of a DiLeu-labeled Saccharomyces cerevisiae lysate digest via high-resolution nano liquid chromatography–tandem mass spectrometry (nanoLC–MS2) analysis on an Orbitrap Elite mass spectrometer. PMID:25405479

  1. Neuronally expressed Ras-family GTPase Di-Ras modulates synaptic activity in Caenorhabditis elegans.

    PubMed

    Tada, Minoru; Gengyo-Ando, Keiko; Kobayashi, Tetsuo; Fukuyama, Masamitsu; Mitani, Shohei; Kontani, Kenji; Katada, Toshiaki

    2012-09-01

    Ras-family GTPases regulate a wide variety of cellular functions including cell growth and differentiation. Di-Ras, which belongs to a distinct subfamily of Ras-family GTPases, is expressed predominantly in brain, but the role of Di-Ras in nervous systems remains totally unknown. Here, we report that the Caenorhabditis elegans Di-Ras homologue drn-1 is expressed specifically in neuronal cells and involved in synaptic function at neuromuscular junctions. Loss of function of drn-1 conferred resistance to the acetylcholinesterase inhibitor aldicarb and partially suppressed the aldicarb-hypersensitive phenotypes of heterotrimeric G-protein mutants, in which acetylcholine release is up-regulated. drn-1 mutants displayed no apparent defects in the axonal distribution of the membrane-bound second messenger diacylglycerol (DAG), which is a key stimulator of acetylcholine release. Finally, we have identified EPAC-1, a C. elegans Epac homologue, as a binding partner for DRN-1. Deletion mutants of epac-1 displayed an aldicarb-resistant phenotype as drn-1 mutants. Genetic analysis of drn-1 and epac-1 showed that they acted in the same pathway to control acetylcholine release. Furthermore, DRN-1 and EPAC-1 were co-immunoprecipitated. These findings suggest that DRN-1 may function cooperatively with EPAC-1 to modulate synaptic activity in C. elegans. PMID:22897658

  2. Synthesis of a Smoothened Cholesterol: 18,19-Di-nor-cholesterol

    PubMed Central

    2015-01-01

    Herein, we report the first synthesis of a demethylated form of cholesterol (18,19-di-nor-cholesterol), in which the C18 and C19 methyl groups of the β-face were eliminated. Recent molecular simulations modeling 18,19-di-nor-cholesterol have suggested that cholesterol’s opposing rough β-face and smooth α-face play necessary roles in cholesterol’s membrane condensing abilities and, additionally, that specific facial preferences are displayed as cholesterol interacts with different neighboring lipids and transmembrane proteins. Inspired by these poorly characterized biochemical interactions, an extensive 18-step synthesis was completed as part of a collaborative effort, wherein synthesizing a “smoothened” cholesterol analogue would provide a direct way to experimentally measure the significance of the β-face methyl groups. Starting from known perhydrochrysenone A, the synthesis of 18,19-di-nor-cholesterol was accomplished with an excellent overall yield of 3.5%. The use of the highly stereoselective Dieckmann condensation and the employment of Evans’ chiral auxiliary were both key to ensuring the success of this synthesis. PMID:24823889

  3. A Basic Behavior of CNG DI Combustion in a Spark-Ignited Rapid Compression Machine

    NASA Astrophysics Data System (ADS)

    Huang, Zuohua; Shiga, Seiichi; Ueda, Takamasa; Jingu, Nobuhisa; Nakamura, Hisao; Ishima, Tsuneaki; Obokata, Tomio; Tsue, Mitsuhiro; Kono, Michikata

    A basic characteristics of compressed natural gas direct-injection (CNG DI) combustion was studied by using a rapid compression machine. Results show that comparing with homogeneous mixture, CNG DI has short combustion duration, high pressure rise due to combustion, and high rate of heat release, which are considered to come from the charge stratification and the gas flow generated by the fuel injection. CNG DI can realize extremely lean combustion which reaches 0.03 equivalence ratio, φ. Combustion duration, maximum pressure rise due to combustion and combustion efficiency are found to be insensitive to the injection modes. Unburned methane showed almost the same level as that of homogeneous mixture combustion. CO increased steeply with the increase in φ when φ was greater than 0.8 due to the excessive stratification, and NOx peak value shifted to the region of lower φ. Combustion inefficiency maintains less than 0.08 in the range of φ from 0.1 to 0.9 and increases at very low φ due to bulk quenching and at higher φ due to excessive stratification. The combustion efficiency estimated from combustion products shows good agreement with that of heat release analysis.

  4. Novel mono-, di-, and trimethylornithine membrane lipids in northern wetland planctomycetes.

    PubMed

    Moore, Eli K; Hopmans, Ellen C; Rijpstra, W Irene C; Villanueva, Laura; Dedysh, Svetlana N; Kulichevskaya, Irina S; Wienk, Hans; Schoutsen, Frans; Sinninghe Damsté, Jaap S

    2013-11-01

    Northern peatlands represent a significant global carbon store and commonly originate from Sphagnum moss-dominated wetlands. These ombrotrophic ecosystems are rain fed, resulting in nutrient-poor, acidic conditions. Members of the bacterial phylum Planctomycetes are highly abundant and appear to play an important role in the decomposition of Sphagnum-derived litter in these ecosystems. High-performance liquid chromatography coupled to high-resolution accurate-mass mass spectrometry (HPLC-HRAM/MS) analysis of lipid extracts of four isolated planctomycetes from wetlands of European north Russia revealed novel ornithine membrane lipids (OLs) that are mono-, di-, and trimethylated at the ε-nitrogen position of the ornithine head group. Nuclear magnetic resonance (NMR) analysis of the isolated trimethylornithine lipid confirmed the structural identification. Similar fatty acid distributions between mono-, di-, and trimethylornithine lipids suggest that the three lipid classes are biosynthetically linked, as in the sequential methylation of the terminal nitrogen in phosphatidylethanolamine to produce phosphatidylcholine. The mono-, di-, and trimethylornithine lipids described here represent the first report of methylation of the ornithine head groups in biological membranes. Various bacteria are known to produce OLs under phosphorus limitation or fatty-acid-hydroxylated OLs under thermal or acid stress. The sequential methylation of OLs, leading to a charged choline-like moiety in the trimethylornithine lipid head group, may be an adaptation to provide membrane stability under acidic conditions without the use of scarce phosphate in nutrient-poor ombrotrophic wetlands. PMID:23995937

  5. Two DHH Subfamily 1 Proteins in Streptococcus pneumoniae Possess Cyclic Di-AMP Phosphodiesterase Activity and Affect Bacterial Growth and Virulence

    PubMed Central

    Bai, Yinlan; Yang, Jun; Eisele, Leslie E.; Underwood, Adam J.; Koestler, Benjamin J.; Waters, Christopher M.; Metzger, Dennis W.

    2013-01-01

    Cyclic di-AMP (c-di-AMP) and cyclic di-GMP (c-di-GMP) are signaling molecules that play important roles in bacterial biology and pathogenesis. However, these nucleotides have not been explored in Streptococcus pneumoniae, an important bacterial pathogen. In this study, we characterized the c-di-AMP-associated genes of S. pneumoniae. The results showed that SPD_1392 (DacA) is a diadenylate cyclase that converts ATP to c-di-AMP. Both SPD_2032 (Pde1) and SPD_1153 (Pde2), which belong to the DHH subfamily 1 proteins, displayed c-di-AMP phosphodiesterase activity. Pde1 cleaved c-di-AMP into phosphoadenylyl adenosine (pApA), whereas Pde2 directly hydrolyzed c-di-AMP into AMP. Additionally, Pde2, but not Pde1, degraded pApA into AMP. Our results also demonstrated that both Pde1 and Pde2 played roles in bacterial growth, resistance to UV treatment, and virulence in a mouse pneumonia model. These results indicate that c-di-AMP homeostasis is essential for pneumococcal biology and disease. PMID:24013631

  6. Crystal structure of di­aqua­bis­(2,6-di­methyl­pyrazine-κN 4)bis­(thio­cyanato-κN)cobalt(II) 2,5-di­methyl­pyrazine monosolvate

    PubMed Central

    Suckert, Stefan; Wöhlert, Susanne; Jess, Inke; Näther, Christian

    2015-01-01

    In the crystal structure of the title compound, [Co(NCS)2(C6H8N2)2(H2O)2]·C6H8N2, the CoII cation is coordinated by the N atoms of two terminal thio­cyanate anions, the O atoms of two water mol­ecules and two N atoms of two 2,6-di­methyl­pyrazine ligands. The coordination sphere of the resulting discrete complex is that of a slightly distorted octa­hedron. The asymmetric unit comprises a CoII cation and half of a 2,5-di­methyl­pyrazine ligand, both of which are located on centres of inversion, and a water ligand, a 2,6-di­­methyl­pyrazine ligand and one thio­cyanate anion in general positions. In the crystal, the discrete complexes are arranged in such a way that cavities are formed in which the 2,5-di­methyl­pyrazine solvent mol­ecules are located. The coordination of the 2,5-di­methyl­pyrazine mol­ecules to the metal is apparently hindered due to the bulky methyl groups in vicinal positions to the N atoms, leading to a preferential coordination of the 2,6-di­methyl­pyrazine ligands. The discrete complexes are linked by O—H⋯N hydrogen bonds between one water H atom and the non-coordinating N atom of the 2,6-di­methyl­pyrazine ligands. The remaining water H atom is hydrogen bonded to one N atom of the 2,5-di­methyl­pyrazine solvent mol­ecule. This arrangement leads to the formation of a two-dimensional network extending parallel to (010). PMID:26870445

  7. Identification, Activity and Disulfide Connectivity of C-di-GMP Regulating Proteins in Mycobacterium tuberculosis

    PubMed Central

    Gupta, Kajal; Kumar, Prasun; Chatterji, Dipankar

    2010-01-01

    C-di-GMP, a bacterial second messenger plays a key role in survival and adaptation of bacteria under different environmental conditions. The level of c-di-GMP is regulated by two opposing activities, namely diguanylate cyclase (DGC) and phosphodiesterase (PDE-A) exhibited by GGDEF and EAL domain, respectively in the same protein. Previously, we reported a bifunctional GGDEFEAL domain protein, MSDGC-1 from Mycobacterium smegmatis showing both these activities (Kumar and Chatterji, 2008). In this current report, we have identified and characterized the homologous protein from Mycobacterium tuberculosis (Rv 1354c) named as MtbDGC. MtbDGC is also a bifunctional protein, which can synthesize and degrade c-di-GMP in vitro. Further we expressed Mtbdgc in M. smegmatis and it was able to complement the MSDGC-1 knock out strain by restoring the long term survival of M. smegmatis. Another protein Rv 1357c, named as MtbPDE, is an EAL domain protein and degrades c-di-GMP to pGpG in vitro. Rv1354c and 1357c have seven cysteine amino acids in their sequence, distributed along the full length of the protein. Disulfide bonds play an important role in stabilizing protein structure and regulating protein function. By proteolytic digestion and mass spectrometric analysis of MtbDGC, connectivity between cysteine pairs Cys94-Cys584, Cys2-Cys479 and Cys429-Cys614 was determined, whereas the third cysteine (Cys406) from N terminal was found to be free in MtbDGC protein, which was further confirmed by alkylation with iodoacetamide labeling. Bioinformatics modeling investigations also supported the pattern of disulfide connectivity obtained by Mass spectrometric analysis. Cys406 was mutated to serine by site directed mutagenesis and the mutant MtbC406S was not found to be active and was not able to synthesize or degrade c-di-GMP. The disulfide connectivity established here would help further in understanding the structure function relationship in MtbDGC. PMID:21151497

  8. Extraction of Palladium from Nitric Acid by Diamides of Di-picolinic Acid

    SciTech Connect

    Alyapyshev, M.Yu.; Babain, V.A.; Pokhitonov, Yu.A.; Esimantovskiy, V.M.

    2007-07-01

    The most complicated and urgent problem of atomic industry consists in the safe isolation and storage of radioactive wastes. The long-lived radionuclides presented in high-level liquid wastes (HLLW) pose a potential threat to environment for hundreds and thousands of years. One of the possible ways to reduce the danger of HLLW storages is concerned with treatment of HLLW intended to recovery of long-lived radionuclides and their partitioning into separate fractions. The separation of the most hazardous radionuclides (like transplutonium elements (TPE)) to the individual fraction of low volume leads to decrease of the total volume of HLLW and therefore to decrease of solidified waste storage costs. It should be noted that only in the case of reprocessing it can be possible to recover individual radionuclides (or their fractions) into separate flows with further special approach to each of them. Partitioning of different HLLW is under investigation in many countries now. Numerous processes for recovery of Cs, Sr, TPE and REE have been already developed and tested. At the same time partitioning is only the first step on the road to the following synthesis of materials providing the safe storage of long-lived radionuclides over many thousands of years. The metallic palladium contained in HLLW seems to be a promising material for producing of matrices for incorporation of radioactive wastes. Different methods for palladium recovery have been investigated: reductive precipitation, electrochemical precipitation, sorption and extraction. Of prime importance are extraction methods. Phosphine oxides, carbamoyl-phosphine oxides, crown-ethers, oximes, sulfides and some other compounds were proposed as extractants towards palladium from nitric acid media. It is reasonable to recover palladium into individual fraction during waste partitioning. Diamides of malonic, di-glycolic and pyridine-dicarboxylic (di-picolinic) acids are intensively investigated as extractants for HLLW partitioning. The data on palladium extraction by amides of pyridinecarboxylic acids from HCl medium are contradictory. It was shown that ethers of pyridine-3,5-dicarboxylic acid effectively recover palladium; at the same time the data given testify that palladium is effectively extracted by diamides of malonic and di-glycolic acids, while amides of di-picolinic acid (solution of N,N'-dimethyl-N,N'-diphenyl diamide of di-picolinic acid in chloroform) do not practically extract palladium from HCl solutions. It was found in our previous works that the use of polar fluorinated diluents instead of chloroform increases the extraction ability of diamides of di-picolinic acid towards americium and europium. The main goal of the present work was to investigate the palladium extraction from nitric acid by solutions of diamides of di-picolinic acid in meta-nitro-benzo-trifluoride (F-3) under conditions that were optimal for Am recovery from HLLW. (authors)

  9. NMR structure and binding studies confirm that PA4608 from Pseudomonas aeruginosa is a PilZ domain and a c-di-GMP binding protein

    SciTech Connect

    Ramelot, Theresa A.; Yee, Adelinda; Cort, John R.; Semesi, Anthony; Arrowsmith, Cheryl H.; Kennedy, Michael A.

    2007-02-01

    PA4608 is a 125 residue protein with a proposed identification as a PilZ domain and c-di-GMP adaptor protein that plays a role in bacterial second-messenger regulated processes. The NMR structure of PA4608 has been determined and c-di-GMP binding has been confirmed by NMR titration studies. The monomeric structure of PA4608 contains a six-stranded anti-parallel ? barrel flanked by three helices. Conserved surface residues among PA4608 homologs suggest the the c-di-GMP binding site is at one end of the barrel and includes residues in the helices as well as in the unstructured N-terminus. Chemical shift changes upon binding to c-di-GMP confirm that PA4608 binds to c-di-GMP. This evidence supports the hypothesis that proteins containing PilZ domains are the long-sought c-di-GMP adaptor proteins.

  10. Analysis of the selective advantage conferred by a C-E1 fusion protein synthesized by rubella virus DI RNAs

    SciTech Connect

    Claus, Claudia; Tzeng, W.-P.; Liebert, Uwe Gerd; Frey, Teryl K.

    2007-12-05

    During serial passaging of rubella virus (RUB) in cell culture, the dominant species of defective-interfering RNA (DI) generated contains an in-frame deletion between the capsid protein (C) gene and E1 glycoprotein gene resulting in production of a C-E1 fusion protein that is necessary for the maintenance of the DI [Tzeng, W.P., Frey, T.K. (2006). C-E1 fusion protein synthesized by rubella virus DI RNAs maintained during serial passage. Virology 356 198-207.]. A BHK cell line stably expressing the RUB structural proteins was established which was used to package DIs into virus particles following transfection with in vitro transcripts from DI infectious cDNA constructs. Packaging of a DI encoding an in-frame C-GFP-E1 reporter fusion protein corresponding to the C-E1 fusion protein expressed in a native DI was only marginally more efficient than packaging of a DI encoding GFP, indicating that the C-E1 fusion protein did not function by enhancing packaging. However, infection with the DI encoding the C-GFP-E1 fusion protein (in the absence of wt RUB helper virus) resulted in formation of clusters of GFP-positive cells and the percentage of GFP-positive cells in the culture following infection remained relatively constant. In contrast, a DI encoding GFP did not form GFP-positive clusters and the percentage of GFP-positive cells declined by roughly half from 2 to 4 days post-infection. Cluster formation and sustaining the percentage of infected (GFP-positive) cells required the C part of the fusion protein, including the downstream but not the upstream of two arginine clusters (both of which are associated with RNA binding and association with mitochondrial p32 protein) and the E1 part through the transmembrane sequence, but not the C-terminal cytoplasmic tail. Among a collection of mutant DI constructs, cluster formation and sustaining infected cell percentage correlated with maintenance during serial passage with wt RUB. We hypothesize that cluster formation and sustaining infected cell percentage increase the likelihood of co-infection by a DI and wt RUB during serial passage thus enhancing maintenance of the DI. Cluster formation and sustaining infected cell percentage were found to be due to a combination of attenuated cytopathogenicity of DIs that express the C-E1 fusion protein and cell-to-cell movement of the DI. In infected cells, the C-GFP-E1 fusion protein was localized to potentially novel vesicular structures that appear to originate from ER-Golgi transport vacuoles. This species of DI expressing a C-E1 fusion protein that exhibits attenuated cytopathogenicity and the ability to increase the number of infected cells through cell-to-cell movement could be the basis for development of an attractive vaccine vector.

  11. The Vibrio cholerae diguanylate cyclase VCA0965 has an AGDEF active site and synthesizes cyclic di-GMP

    PubMed Central

    2014-01-01

    Background Diguanylate cyclases (DGCs) regulate biofilm formation and motility in bacteria by synthesizing the second messenger cyclic di-GMP (c-di-GMP) in response to environmental stimuli. DGC enzymatic activity is believed to be dependent on the presence of a GG(D/E)EF active site motif, however approximately 25% of known DGCs contain a degenerate active site. The Vibrio cholerae protein VCA0965 contains an AGDEF active site and is presumed to be an inactive DGC. Results Ectopic expression of VCA0965 in V. cholerae causes a 3-fold reduction in flagellar-based motility. Additionally, an RXXD allosteric inhibition mutant of VCA0965 strongly inhibited motility and stimulated biofilm formation. This activity was lost when the active site of VCA0965 was mutated to AGDAF, suggesting that VCA0965 synthesizes c-di-GMP. In support of this, ectopic expression of VCA0965 and VCA0965 containing a mutation in its RXXD motif significantly increased the intracellular c-di-GMP levels in V. cholerae and Escherichia coli. Furthermore, we found that purified VCA0965 was able to synthesize c-di-GMP in vitro. Systematic mutation of the first amino acid in the AGDEF motif of VCA0965 revealed that glycine, methionine, and histidine also produced an active DGC capable of inhibiting motility and increasing the intracellular concentration of c-di-GMP in V. cholerae. Conclusions Based on these results, we conclude that VCA0965 is capable of c-di-GMP synthesis and that the first amino acid of the GG(D/E)EF motif is more tolerant of substitutions than currently appreciated. PMID:24490592

  12. Cyclic-di-AMP synthesis by the diadenylate cyclase CdaA is modulated by the peptidoglycan biosynthesis enzyme GlmM in Lactococcus lactis.

    PubMed

    Zhu, Yan; Pham, Thi Huong; Nhiep, Thi Hanh Nguyen; Vu, Ngoc Minh Thu; Marcellin, Esteban; Chakrabortti, Alolika; Wang, Yuanliang; Waanders, Jennifer; Lo, Raquel; Huston, Wilhelmina M; Bansal, Nidhi; Nielsen, Lars K; Liang, Zhao-Xun; Turner, Mark S

    2016-03-01

    The second messenger cyclic-di-adenosine monophosphate (c-di-AMP) plays important roles in growth, virulence, cell wall homeostasis, potassium transport and affects resistance to antibiotics, heat and osmotic stress. Most Firmicutes contain only one c-di-AMP synthesizing diadenylate cyclase (CdaA); however, little is known about signals and effectors controlling CdaA activity and c-di-AMP levels. In this study, a genetic screen was employed to identify components which affect the c-di-AMP level in Lactococcus. We characterized suppressor mutations that restored osmoresistance to spontaneous c-di-AMP phosphodiesterase gdpP mutants, which contain high c-di-AMP levels. Loss-of-function and gain-of-function mutations were identified in the cdaA and gdpP genes, respectively, which led to lower c-di-AMP levels. A mutation was also identified in the phosphoglucosamine mutase gene glmM, which is commonly located within the cdaA operon in bacteria. The glmM I154F mutation resulted in a lowering of the c-di-AMP level and a reduction in the key peptidoglycan precursor UDP-N-acetylglucosamine in L. lactis. C-di-AMP synthesis by CdaA was shown to be inhibited by GlmM(I154F) more than GlmM and GlmM(I154F) was found to bind more strongly to CdaA than GlmM. These findings identify GlmM as a c-di-AMP level modulating protein and provide a direct connection between c-di-AMP synthesis and peptidoglycan biosynthesis. PMID:26585449

  13. 40 CFR 721.10442 - 1,2-Benzenedicarboxylic acid, di-C6-14-branched and linear alkyl esters.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false 1,2-Benzenedicarboxylic acid, di-C6-14... Significant New Uses for Specific Chemical Substances 721.10442 1,2-Benzenedicarboxylic acid, di-C6-14...) The chemical substance identified as 1,2-benzenedicarboxylic acid, di-C6-14-branched and linear......

  14. 40 CFR 721.10441 - 1,2-Benzenedicarboxylic acid, di-C7-14-branched and linear alkyl esters.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false 1,2-Benzenedicarboxylic acid, di-C7-14... Significant New Uses for Specific Chemical Substances 721.10441 1,2-Benzenedicarboxylic acid, di-C7-14...) The chemical substance identified as 1,2-benzenedicarboxylic acid, di-C7-14-branched and linear......

  15. 40 CFR 721.10442 - 1,2-Benzenedicarboxylic acid, di-C6-14-branched and linear alkyl esters.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false 1,2-Benzenedicarboxylic acid, di-C6-14... Significant New Uses for Specific Chemical Substances 721.10442 1,2-Benzenedicarboxylic acid, di-C6-14...) The chemical substance identified as 1,2-benzenedicarboxylic acid, di-C6-14-branched and linear......

  16. 40 CFR 721.10441 - 1,2-Benzenedicarboxylic acid, di-C7-14-branched and linear alkyl esters.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false 1,2-Benzenedicarboxylic acid, di-C7-14... Significant New Uses for Specific Chemical Substances 721.10441 1,2-Benzenedicarboxylic acid, di-C7-14...) The chemical substance identified as 1,2-benzenedicarboxylic acid, di-C7-14-branched and linear......

  17. Synthesis, structural characterization, electronic spectroscopy, and microfluidic detection of Cu+2 and UO2+2 [di-tert-butyl-salphenazine] complexes†

    PubMed Central

    Maynard, B. A.; Brooks, J. C.; Hardy, E. E.; Easley, C. J.; Gorden, A. E. V.

    2015-01-01

    Metal templation by condensation of 2,3-diaminophenazine with 3,5-di-tert-butyl-2-hydroxybenzaldehyde around the metal centers [M = Cu(ii), and UO2(vi)] affords a new class of M[di-tert-butyl sal-phenazine] metal complexes. Reported here is the synthesis, single crystal X-ray structural characterization, electronic spectroscopy, and microfluidic detection of the formation of these M[di-tert-butyl sal-phenazine] complexes. PMID:25657039

  18. 40 CFR 721.9730 - 1,3,5-Triazin-2-amine, 4-di-meth-yl-a-mino-6-substituted-.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false 1,3,5-Triazin-2-amine, 4-di-meth-yl-a... New Uses for Specific Chemical Substances § 721.9730 1,3,5-Triazin-2-amine, 4-di-meth-yl-a-mino-6...-2-amine, 4-di-meth-yl-a-mino-6-substituted- (PMN Nos. P-92-343 and P-92-344) are subject...

  19. 40 CFR 721.9730 - 1,3,5-Triazin-2-amine, 4-di-meth-yl-a-mino-6-substituted-.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false 1,3,5-Triazin-2-amine, 4-di-meth-yl-a... New Uses for Specific Chemical Substances § 721.9730 1,3,5-Triazin-2-amine, 4-di-meth-yl-a-mino-6... substances generically identified as 1,3,5-triazin-2-amine, 4-di-meth-yl-a-mino-6-substituted- (PMN Nos....

  20. 40 CFR 721.9730 - 1,3,5-Triazin-2-amine, 4-di-meth-yl-a-mino-6-substituted-.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false 1,3,5-Triazin-2-amine, 4-di-meth-yl-a... New Uses for Specific Chemical Substances § 721.9730 1,3,5-Triazin-2-amine, 4-di-meth-yl-a-mino-6... substances generically identified as 1,3,5-triazin-2-amine, 4-di-meth-yl-a-mino-6-substituted- (PMN Nos....

  1. 40 CFR 721.9730 - 1,3,5-Triazin-2-amine, 4-di-meth-yl-a-mino-6-substituted-.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false 1,3,5-Triazin-2-amine, 4-di-meth-yl-a... New Uses for Specific Chemical Substances § 721.9730 1,3,5-Triazin-2-amine, 4-di-meth-yl-a-mino-6... substances generically identified as 1,3,5-triazin-2-amine, 4-di-meth-yl-a-mino-6-substituted- (PMN Nos....

  2. 40 CFR 721.9730 - 1,3,5-Triazin-2-amine, 4-di-meth-yl-a-mino-6-substituted-.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false 1,3,5-Triazin-2-amine, 4-di-meth-yl-a... New Uses for Specific Chemical Substances § 721.9730 1,3,5-Triazin-2-amine, 4-di-meth-yl-a-mino-6... substances generically identified as 1,3,5-triazin-2-amine, 4-di-meth-yl-a-mino-6-substituted- (PMN Nos....

  3. Crystal structure of di­chlorido­bis­(N,N′-di­methyl­thio­urea-κS)mercury(II)

    PubMed Central

    Shaheen, Muhammad Ashraf; Munawar, Aisha; Sadaf, Haseeba; Tahir, Muhammad Nawaz; Isab, Anvarhusein A.; Ahmad, Saeed

    2015-01-01

    The mol­ecular structure of the title compound, [HgCl2(C3H8N2S)2], has point group symmetry 2, with the twofold rotation axis passing through the HgII atom. The latter is coordinated by two Cl atoms and two N,N′-di­methyl­thio­urea (Dmtu) ligands through their S atoms, defining a distorted tetra­hedral coordination sphere with bond angles in the range 102.47 (4)–118.32 (4)°. Intra- and inter­molecular hydrogen bonds of the type N—H⋯Cl with S(6) and R 2 2(12) ring motifs are present. The inter­molecular contacts make up polymeric chains extending parallel to [101]. PMID:26396848

  4. Effects of di-n-butyl phthalate and di (2-ethylhexyl) phthalate on the growth, photosynthesis, and chlorophyll fluorescence of wheat seedlings.

    PubMed

    Gao, Minling; Qi, Yun; Song, Wenhua; Xu, Haoran

    2016-05-01

    Phthalates are commonly used man-made chemicals that can be released into soil, water, and the atmosphere. The potential toxicity of phthalates on wheat seedlings has not been well studied. To better understand the deleterious effects of di-n-butyl phthalate (DBP) and di (2-ethylhexyl) phthalate (DEHP) on wheat seedlings, their influences on the following were investigated: plant growth, net photosynthetic rate (Pn), stomatal conductance (Gs), transpiration rate (Tr), intercellular CO2 concentration (Ci), chlorophyll content, initial fluorescence (F0), maximal photochemical efficiency (Fv/Fm), photochemical quenching (qP), non-photochemical quenching (qN), effective quantum yield of photosystem II (ΦPSII), and photosynthetic electron transport rate (ETR). Compared with the control, the growth indices (plant height, fresh and dry weights of shoots, fresh and dry weights of roots), Pn, Gs, Tr, Ci, chlorophyll content, Fv/Fm, qP, ΦPSII, and ETR decreased in the 5 μg mL(-1) and 10 μg mL(-1) DBP and DEHP treatments, whereas F0 and qN increased. When wheat seedlings were treated with 20 μg mL(-1) of DBP and DEHP, the growth indices, Pn, Gs, Tr, chlorophyll content, Fv/Fm, qP, qN, ΦPSII, and ETR decreased significantly, whereas Ci and F0 increased. A decrease in the Pn of wheat seedlings was mainly caused by stomatal limitation in the 5 μg mL(-1) and 10 μg mL(-1) DBP and DEHP treatments. However, stomatal and non-stomatal limitations may have caused the reduction in Pn in the 20 μg mL(-1) DBP and DEHP treatments. Notably, the noxious effect of DBP on the wheat seedlings was significantly greater than that of DEHP. PMID:26928333

  5. Aerobic biodegradation of toluene-2,4-di(8:2 fluorotelomer urethane) and hexamethylene-1,6-di(8:2 fluorotelomer urethane) monomers in soils.

    PubMed

    Dasu, Kavitha; Lee, Linda S

    2016-02-01

    Aerobic soil biodegradation of toluene-2,4-di(8:2 fluorotelomer urethane) (FTU) and hexamethylene-1,6-di(8:2 fluorotelomer urethane) (HMU) in a forest soil and FTU in an agricultural silty clay loam soil was monitored for up to 6 months. Fluorotelomer alcohols were measured in headspace and parent monomers and all metabolites in soil extracts. Negligible degradation of FTU biodegradation occurred in the agricultural soil with 94 ± 15% recovered at day 180. However, in the forest soil, both FTU and HMU degradation was evident with significant losses of 24% (117 d) and 27% (180 day), respectively, and concomitant increases in the terminal metabolite, perfluorooctanoic acid (PFOA) concentrations were well above what could result from residual 8:2 FTOH. Kinetic modeling estimated half-lives for FTU (aromatic backbone) and HMU (aliphatic backbone) in the forest soil to be 3-5 months and 15.9-22.2 months, respectively. The addition of a structurally similar non-fluorinated FTU analog, toluene-2,4-dicarbamic acid diethyl ester (TDAEE) enhanced production of terminal end products from 8:2 FTOH degradation. However, there was no clear evidence that TDAEE enhanced cleavage of the urethane bond, thus TDAEE appeared to just serve as an additional carbon source. TDAEE's half-life was ∼ one week. A second addition of TDAEE appeared to retard subsequent degradation of FTU exemplifying the microbial dynamics and diversity impacting degradation of polyfluoroalkyl substances. Enhanced degradation of HMU was observed upon re-aeration indicating oxygen may have been limiting during some periods although degradation of intermediate metabolites to terminal metabolites was still occurring, albeit at slower rates. PMID:26624955

  6. E88, a new cyclic-di-GMP class I riboswitch aptamer from Clostridium tetani, has a similar fold to the prototypical class I riboswitch, Vc2, but differentially binds to c-di-GMP analogs.

    PubMed

    Luo, Yiling; Chen, Bin; Zhou, Jie; Sintim, Herman O; Dayie, T Kwaku

    2014-03-01

    C-di-GMP has emerged as a ubiquitous second messenger, which regulates the transition between sessile and motile lifestyles and virulence factor expression in many pathogenic bacteria using both RNA riboswitches and protein effectors. We recently showed that two additional class I c-di-GMP riboswitch aptamers (Ct-E88 and Cb-17B) bind c-di-GMP with nanomolar affinity, and that Ct-E88 RNA binds 2'-F-c-di-GMP 422 times less tightly than class I Vc2 RNA. Based on sequence comparison, it was concluded that the global folds of Ct-E88 and Vc2 RNAs were similar and that differences in ligand binding were probably due to differences in binding site architectures. Herein, we utilized EMSA, aptamer sensing spinach modules, SAXS and 1D NMR titration to study the conformational transitions of Ct-E88. We conclude that whereas the global folds of the bound states of Vc2 and Ct-E88 RNAs are similar, the unbound states are different and this could explain differences in ligand affinities between these class I c-di-GMP riboswitches. PMID:24430255

  7. ChIP-seq reveals the global regulator AlgR mediating cyclic di-GMP synthesis in Pseudomonas aeruginosa.

    PubMed

    Kong, Weina; Zhao, Jingru; Kang, Huaping; Zhu, Miao; Zhou, Tianhong; Deng, Xin; Liang, Haihua

    2015-09-30

    AlgR is a key transcriptional regulator required for the expression of multiple virulence factors, including type IV pili and alginate in Pseudomonas aeruginosa. However, the regulon and molecular regulatory mechanism of AlgR have yet to be fully elucidated. Here, among 157 loci that were identified by a ChIP-seq assay, we characterized a gene, mucR, which encodes an enzyme that synthesizes the intracellular second messenger cyclic diguanylate (c-di-GMP). A ΔalgR strain produced lesser biofilm than did the wild-type strain, which is consistent with a phenotype controlled by c-di-GMP. AlgR positively regulates mucR via direct binding to its promoter. A ΔalgRΔmucR double mutant produced lesser biofilm than did the single ΔalgR mutant, demonstrating that c-di-GMP is a positive regulator of biofilm formation. AlgR controls the levels of c-di-GMP synthesis via direct regulation of mucR. In addition, the cognate sensor of AlgR, FimS/AlgZ, also plays an important role in P. aeruginosa virulence. Taken together, this study provides new insights into the AlgR regulon and reveals the involvement of c-di-GMP in the mechanism underlying AlgR regulation. PMID:26206672

  8. Current Status of Divertor Plasma Simulator (DiPS-2) for Dust Interactions with Plasma and Surfaces

    NASA Astrophysics Data System (ADS)

    Kang, In Je; Cho, Soon-Gook; Bae, Min Keun; Lee, Dong-Han; Kim, Sang-You; Hong, Sung-Hoon; Choi, Heung-Gyoon; Lho, Tae-Hyup; Chung, Kyu-Sun

    2015-09-01

    The divertor plasma simulator (DiPS-2) which is a linear plasma machine with ~ 8 MW/m2 power density emitted from a DC plasma discharge source with a LaB6 cathode is under installation for experiments of dust interactions with plasma and surfaces in fusion research fields. Specifications of DiPS-2 have weakly magnetized helium plasmas (density ~ 1013 cm3, electron temperature ~ 1 - 10 eV, particle flux ~ 1023/(sec .m2), which are of the order of plasma parameters in a typical divertor. Currently, a vacuum chamber with the diameter of 560 mm and the length of 800 mm called as ``dust interaction with surface chamber (DiSC)'' is being setup to an end flange of DiPS-2. The DiSC has a load-lock system for easily changing material targets and plasma diagnostics systems such as laser induced fluorescence (LIF), laser Thomson scattering (LTS), thermocouples and fast scanning probes (FSP) with SP, TP and MP. Using the measured dust and plasma parameters, SOL heat flux width (λq) and sheath heat transmission factor (γs) will be experimentally deduced for the analysis of the dust effects to plasmas. Initial probe data will be addressed.

  9. ChIP-seq reveals the global regulator AlgR mediating cyclic di-GMP synthesis in Pseudomonas aeruginosa

    PubMed Central

    Kong, Weina; Zhao, Jingru; Kang, Huaping; Zhu, Miao; Zhou, Tianhong; Deng, Xin; Liang, Haihua

    2015-01-01

    AlgR is a key transcriptional regulator required for the expression of multiple virulence factors, including type IV pili and alginate in Pseudomonas aeruginosa. However, the regulon and molecular regulatory mechanism of AlgR have yet to be fully elucidated. Here, among 157 loci that were identified by a ChIP-seq assay, we characterized a gene, mucR, which encodes an enzyme that synthesizes the intracellular second messenger cyclic diguanylate (c-di-GMP). A ΔalgR strain produced lesser biofilm than did the wild-type strain, which is consistent with a phenotype controlled by c-di-GMP. AlgR positively regulates mucR via direct binding to its promoter. A ΔalgRΔmucR double mutant produced lesser biofilm than did the single ΔalgR mutant, demonstrating that c-di-GMP is a positive regulator of biofilm formation. AlgR controls the levels of c-di-GMP synthesis via direct regulation of mucR. In addition, the cognate sensor of AlgR, FimS/AlgZ, also plays an important role in P. aeruginosa virulence. Taken together, this study provides new insights into the AlgR regulon and reveals the involvement of c-di-GMP in the mechanism underlying AlgR regulation. PMID:26206672

  10. Donor-linked di(perylene bisimide)s: arrays exhibiting fast electron transfer for photosynthesis mimics.

    PubMed

    Wu, Yishi; Zhen, Yonggang; Wang, Zhaohui; Fu, Hongbing

    2013-02-28

    The first example of donor-linked di(perylene bisimide)s is reported. UV-vis absorption spectra of these newly synthesized dyads showed intense absorption across the entire visible region, demonstrating their excellent light-harvesting activities. The severe fluorescence quenching event probed by steady-state fluorescence spectroscopy and the free-energy calculations suggested the possibility of electron transfer (ET) in these arrays upon photoexcitation. Further femtosecond transient absorption spectra clarified that the fluorescence quenching was due to fast intramolecular ET. The rate of the charge separation (CS) was found to be as high as 10(12) s(-1) in CH(2)Cl(2). It was suggested that the large ET driving forces, strong donor-acceptor electronic coupling, and relatively small reorganization energy of diPBI accounted for the rapid ET process in a synergic manner. The fate of the generated radical ion pair depended on the solvent used. Rapid charge recombination to ground state occurred for the dyads in polar CH(2)Cl(2) and for diPBI-TPA in nonpolar toluene. However, sufficient (3)diPBI* population was attained via efficient spin-orbit coupled intersystem crossing from the charge-separated state for diPBI-PdTPP in toluene. These photophysical properties are interpreted as the cooperation between thermodynamic feasibility and kinetic manipulation. PMID:23391220

  11. Evaluation of a di-O-methylated glycan as a potential antigenic target for the serodiagnosis of human toxocariasis.

    PubMed

    Elefant, G R; Roldán, W H; Seeböck, A; Kosma, P

    2016-04-01

    Serodiagnosis of human toxocariasis is based on the detection of specific IgG antibodies by the enzyme-linked immunosorbent assay (ELISA) using Toxocara larvae excretory-secretory (TES) antigens, but its production is a laborious and time-consuming process being also limited by the availability of adult females of T. canis as source for ova to obtain larvae. Chemical synthesis of the di-O-methylated (DiM) glycan structure found in the TES antigens has provided material for studying the antibody reactivity in a range of mammalian hosts, showing reactivity with human IgM and IgG. In this study, we have evaluated the performance of the DiM glycan against a panel of sera including patients with toxocariasis (n = 60), patients with other helminth infections (n = 75) and healthy individuals (n = 94), showing that DiM is able to detect IgG antibodies with a sensitivity and specificity of 91·7% and 94·7%, respectively, with a very good agreement with the TES antigens (kappa = 0·825). However, cross-reactivity was observed in some sera from patients with ascariasis, hymenolepiasis and fascioliasis. These results show that the DiM glycan could be a promising antigenic tool for the serodiagnosis of human toxocariasis. PMID:26896376

  12. Synthetic di-sulfated iduronic acid attenuates asthmatic response by blocking T-cell recruitment to inflammatory sites.

    PubMed

    Nonaka, Motohiro; Bao, Xingfeng; Matsumura, Fumiko; Götze, Sebastian; Kandasamy, Jeyakumar; Kononov, Andrew; Broide, David H; Nakayama, Jun; Seeberger, Peter H; Fukuda, Minoru

    2014-06-01

    Identification of carbohydrate sequences that determine affinity to specific chemokines is a critical step for strategies to interfere with chemokine-mediated leukocyte trafficking. Here, we first characterized the development of allergic asthma in Tie2-dependent and inducible Ext1-knockout (Tie2-Ext1(iKO)) mice. We showed that heparan sulfate is essential for leukocyte recruitment in the peribronchial region and bronchoalveolar lavage fluid (BALF), and is crucial for induction of airway hyperresponsiveness. Our glycan microarray showed a unique affinity profile of chemokine CCL20 to substructures of heparin and heparin-like oligo/di/monosaccharides. Among them, we identified a synthetic and not naturally occurring monosaccharide, 2,4-O-di-sulfated iduronic acid (Di-S-IdoA), as a potential inhibitor for CCL20-heparan sulfate interaction. Mice injected with Di-S-IdoA via tail vain or nasal inhalation showed attenuated leukocyte recruitment into inflammatory sites and BALF. These results demonstrate a critical role of chemokine-heparan sulfate interaction in the asthma development and Di-S-IdoA as a potential drug for asthma treatment. PMID:24835176

  13. Di-Leucine Signals Mediate Targeting of Tyrosinase and Synaptotagmin to Synaptic-like Microvesicles within PC12 Cells

    PubMed Central

    Blagoveshchenskaya, Anastasiya D.; Hewitt, Eric W.; Cutler, Daniel F.

    1999-01-01

    One pathway in forming synaptic-like microvesicles (SLMV) involves direct budding from the plasma membrane, requires adaptor protein 2 (AP2) and is brefeldin A (BFA) resistant. A second route leads from the plasma membrane to an endosomal intermediate from which SLMV bud in a BFA-sensitive, AP3-dependent manner. Because AP3 has been shown to bind to a di-leucine targeting signal in vitro, we have investigated whether this major class of targeting signals is capable of directing protein traffic to SLMV in vivo. We have found that a di-leucine signal within the cytoplasmic tail of human tyrosinase is responsible for the majority of the targeting of HRP-tyrosinase chimeras to SLMV in PC12 cells. Furthermore, we have discovered that a Met-Leu di-hydrophobic motif within the extreme C terminus of synaptotagmin I supports 20% of the SLMV targeting of a CD4-synaptotagmin chimera. All of the traffic to the SLMV mediated by either di-Leu or Met-Leu is BFA sensitive, strongly suggesting a role for AP3 and possibly for an endosomal intermediate in this process. The differential reduction in SLMV targeting for HRP-tyrosinase and CD4-synaptotagmin chimeras by di-alanine substitutions or BFA treatment implies that different proteins use the two routes to the SLMV to differing extents. PMID:10564285

  14. Focusing the lens of language experience: Perception of Ma'di stops by Greek and English bilinguals and monolinguals

    PubMed Central

    Antoniou, Mark; Best, Catherine T.; Tyler, Michael D.

    2013-01-01

    Monolingual listeners are constrained by native language experience when categorizing and discriminating unfamiliar non-native contrasts. Are early bilinguals constrained in the same way by their two languages, or do they possess an advantage? Greek–English bilinguals in either Greek or English language mode were compared to monolinguals on categorization and discrimination of Ma'di stop-voicing distinctions that are non-native to both languages. As predicted, English monolinguals categorized Ma'di prevoiced plosive and implosive stops and the coronal voiceless stop as English voiced stops. The Greek monolinguals categorized the Ma'di short-lag voiceless stops as Greek voiceless stops, and the prevoiced implosive stops and the coronal prevoiced stop as Greek voiced stops. Ma'di prenasalized stops were uncategorized. Greek monolinguals discriminated the non-native voiced-voiceless contrasts very well, whereas the English monolinguals did poorly. Bilinguals were given all oral and written instructions either in English or in Greek (language mode manipulation). Each language mode subgroup categorized Ma'di stop-voicing comparably to the corresponding monolingual group. However, the bilinguals’ discrimination was unaffected by language mode: both subgroups performed intermediate to the monolinguals for the prevoiced-voiceless contrast. Thus, bilinguals do not possess an advantage for unfamiliar non-native contrasts, but are nonetheless uniquely configured language users, differing from either monolingual group. PMID:23556605

  15. The 750 GeV di-photon LHC excess and extra Z^' s in heterotic-string derived models

    NASA Astrophysics Data System (ADS)

    Faraggi, Alon E.; Rizos, John

    2016-03-01

    The ATLAS and CMS collaborations recently recorded possible di-photon excess at 750 GeV and a less significant di-boson excess around 1.9 TeV. Such excesses may be produced in heterotic string derived Z^' models, where the di-photon excess may be connected with the Standard Model singlet scalar responsible for the Z^' symmetry breaking, whereas the di-boson excess arises from production of the extra vector boson. Additional vector-like states in the string Z^' model are instrumental to explain the relatively large width of the di-photon events and mandated by anomaly cancellation to be in the vicinity of the Z^' breaking scale. Wilson line breaking of the non-Abelian gauge symmetries in the string models naturally gives rise to dark matter candidates. Future collider experiments will discriminate between the high-scale heterotic-string models, which preserve the perturbative unification paradigm indicated by the Standard Model data, versus the low scale string models. We also discuss the possibility for the production of the diphoton events with high scale U(1)_{Z^' } breaking.

  16. Di-J/psi Studies, Level 3 Tracking and the D0 Run IIb Upgrade

    SciTech Connect

    Vint, Philip John; /Imperial Coll., London

    2009-10-01

    The D0 detector underwent an upgrade to its silicon vertex detector and triggering systems during the transition from Run IIa to Run IIb to maximize its ability to fully exploit Run II at the Fermilab Tevatron. This thesis describes improvements made to the tracking and vertexing algorithms used by the high level trigger in both Run IIa and Run IIb, as well as a search for resonant di-J/{psi} states using both Run IIa and Run IIb data. Improvements made to the tracking and vertexing algorithms during Run IIa included the optimization of the existing tracking software to reduce overall processing time and the certification and testing of a new software release. Upgrades made to the high level trigger for Run IIb included the development of a new tracking algorithm and the inclusion of the new Layer 0 silicon detector into the existing software. The integration of Layer 0 into the high level trigger has led to an improvement in the overall impact parameter resolution for tracks of {approx}50%. The development of a new parameterization method for finding the error associated to the impact parameter of tracks returned by the high level tracking algorithm, in association with the inclusion of Layer 0, has led to improvements in vertex resolution of {approx}4.5 {micro}m. A previous search in the di-J/{psi} channel revealed a unpredicted resonance at {approx}13.7 GeV/c{sup 2}. A confirmation analysis is presented using 2.8 fb{sup -1} of data and two different approaches to cuts. No significant excess is seen in the di-J/{psi} mass spectrum.

  17. High abundance of novel environmental chlamydiae in a Tyrrhenian coastal lake (Lago di Paola, Italy).

    PubMed

    Pizzetti, Ilaria; Fazi, Stefano; Fuchs, Bernhard M; Amann, Rudolf

    2012-08-01

    For a long time the bacterial phylum of Chlamydiae exclusively consisted of one family of obligate intracellular bacteria, the Chlamydiaceae, which encompassed causative agents of severe diseases. In the 1990s, environmental chlamydiae were discovered as symbionts of free-living amoebae and other eukaryotic hosts. During a sampling campaign in September 2008, while monitoring Planctomycetes, we retrieved 20 almost full-length 16S rRNA gene sequences affiliated with Chlamydiales from a lake at the Tyrrhenian coast of central Italy (Lago di Paola, Latium). Two main clusters were identified. The nine sequences within the tight cluster I shared ∼98% identity, just like the six sequences of cluster II. The 16S rRNA sequence identity between the two novel groups was with 88% higher than with all known families of the order Chlamydiales. Four types of less frequent chlamydial 16S rRNA sequences were also detected. Two oligonucleotide probes were designed, and optimized. Chl282 targets the cluster I and almost all other Chlamydiales, while Chl282bis targets the cluster II and few other sequences. By catalysed reporter deposition fluorescence in situ hybridization (CARD-FISH), we identified in the Lago di Paola picoplankton abundant tiny cells with dot-shaped morphology and, interestingly, rarely also protists with intracellular pleomorphic chlamydiae. Abundances of the novel chlamydial clusters were up to 5 × 10(4) cells per millilitre. The two clusters were also detected in similar numbers during a second sampling in October 2010. This confirmed the relevance of the two newly described clusters of chlamydiae in Lago di Paola, not only enlarging the knowledge on the biodiversity of environmental chlamydiae in aquatic habitats, but also raising sanitary issues that should be addressed in the future. PMID:23760831

  18. Combining DI-ESI–MS and NMR datasets for metabolic profiling

    PubMed Central

    Marshall, Darrell D.; Lei, Shulei; Worley, Bradley; Huang, Yuting; Garcia-Garcia, Aracely; Franco, Rodrigo; Dodds, Eric D.; Powers, Robert

    2014-01-01

    Metabolomics datasets are commonly acquired by either mass spectrometry (MS) or nuclear magnetic resonance spectroscopy (NMR), despite their fundamental complementarity. In fact, combining MS and NMR datasets greatly improves the coverage of the metabolome and enhances the accuracy of metabolite identification, providing a detailed and high-throughput analysis of metabolic changes due to disease, drug treatment, or a variety of other environmental stimuli. Ideally, a single metabolomics sample would be simultaneously used for both MS and NMR analyses, minimizing the potential for variability between the two datasets. This necessitates the optimization of sample preparation, data collection and data handling protocols to effectively integrate direct-infusion MS data with one-dimensional (1D) 1H NMR spectra. To achieve this goal, we report for the first time the optimization of (i) metabolomics sample preparation for dual analysis by NMR and MS, (ii) high throughput, positive-ion direct infusion electrospray ionization mass spectrometry (DI-ESI-MS) for the analysis of complex metabolite mixtures, and (iii) data handling protocols to simultaneously analyze DI-ESI-MS and 1D 1H NMR spectral data using multiblock bilinear factorizations, namely multiblock principal component analysis (MB-PCA) and multiblock partial least squares (MB-PLS). Finally, we demonstrate the combined use of backscaled loadings, accurate mass measurements and tandem MS experiments to identify metabolites significantly contributing to class separation in MB-PLS-DA scores. We show that integration of NMR and DI-ESI-MS datasets yields a substantial improvement in the analysis of neurotoxin involvement in dopaminergic cell death. PMID:25774104

  19. Effects of Injector Conditions on the Flame Lift-Off Length of DI Diesel Sprays

    SciTech Connect

    D. L. Siebers; B. S. Higgins

    2000-07-01

    The effects of injection pressure and orifice diameter on the lift-off length of a direct-injection (DI) diesel spray (defined as the farthest upstream location of high temperature combustion) were investigated using a natural light emission imaging technique. The lift-off length experiments were conducted in a constant-volume combustion vessel under quiescent, heavy-duty DI diesel engine conditions using a Phillips research grade No.2 diesel fuel. The results show that natural light emission at 310 nm provides an excellent marker of the lift-off length. At this location, natural light emission at 310 nm is dominated by OH chemiluminescence generated by high-temperature combustion chemistry. Lift-off lengths determined from images of natural light emission at 310 nm show that as either injection pressure (i.e., injection velocity) or orifice diameter increase, the lift-off length increases. The observed lift-off length increase was linearly dependent on injection velocity, the same dependency as previously noted for gas jets. The lift-off length increase with increasing orifice diameter, however, is different than the independence of lift-off length on orifice diameter noted for gas jets An important overall observation was made by considering the lift-off length data in conjunction with data from recent investigations of liquid-phase fuel penetration and spray development. The combined data suggests that a systematic evolution of the relationship and interaction between various processes in a DI diesel spray has been occurring over time, as injection pressures have been increased and orifice diameters reduced as part of efforts to meet emissions regulations. The trends observed may eventually help explain effects of parameters such as injection pressure and orifice diameter on emissions.

  20. Three-dimensional cell culture of chondrocytes on modified di-phenylalanine scaffolds.

    PubMed

    Jayawarna, V; Smith, A; Gough, J E; Ulijn, R V

    2007-06-01

    The design of self-assembled peptide-based structures for three-dimensional cell culture and tissue repair has been a key objective in biomaterials science for decades. In search of the simplest possible peptide system that can self-assemble, we discovered that combinations of di-peptides that are modified with aromatic stacking ligands could form nanometre-sized fibres when exposed to physiological conditions. For example, we demonstrated that a number of Fmoc (fluoren-9-ylmethyloxycarbonyl) modified di- and tri-peptides form highly ordered hydrogels via hydrogen-bonding and pi-pi interactions from the fluorenyl rings. These highly hydrated gels allowed for cell proliferation of chondrocytes in three dimensions [Jayawarna, Ali, Jowitt, Miller, Saiani, Gough and Ulijn (2006) Adv. Mater. 18, 611-614]. We demonstrated that fibrous architecture and physical properties of the resulting materials were dictated by the nature of the amino acid building blocks. Here, we report the self-assembly process of three di-phenylalanine analogues, Fmoc-Phe-Phe-OH, Nap (naphthalene)-Phe-Phe-OH and Cbz (benzyloxycarbonyl)-Phe-Phe-OH, to compare and contrast the self-assembly properties and cell culture conditions attributable to their protecting group difference. Fibre morphology analysis of the three structures using cryo-SEM (scanning electron microscopy) and TEM (transmission electron microscopy) suggested fibrous structures with dramatically varying fibril dimensions, depending on the aromatic ligand used. CD and FTIR (Fourier-transform IR) data confirmed beta-sheet arrangements in all three samples in the gel state. The ability of these three new hydrogels to support cell proliferation of chondrocytes was confirmed for all three materials. PMID:17511646

  1. Magnetocaloric properties of manganese(III) porphyrins bearing 2,6-di-tert-butylphenol groups

    NASA Astrophysics Data System (ADS)

    Korolev, V. V.; Lomova, T. N.; Maslennikova, A. N.; Korolev, D. V.; Shpakovsky, D. B.; Zhang, Jianwei; Milaeva, E. R.

    2016-03-01

    Magnetocaloric effect (MCE) and heat capacity during the magnetization of (5,10,15,20-tetrakis(3,5-di-tert-butyl-4-hydroxyphenyl)porphynato) manganese (III) chloride (1), (5-(4-hydroxyphenyl)-10,15,20-tris(3,5-di-tert-butyl-4-hydroxyphenyl)porphynato) manganese (III) chloride (2), and (5-(4-palmitoyloxyphenyl)-10,15,20-tris(3,5-di-tert-butyl-4-hydroxyphenyl)porphynato) manganese (III) chloride (3) in their aqueous suspensions were determined by the microcalorimetric method over the temperature range of 278-320 K and in magnetic fields from 0 to 1 T. MCE was positive for all complexes studied, i.e. the magnetic field impression under adiabatic conditions led to an increase in temperature of the complexes suspensions. MCE increased with an increase in the magnetic field induction at all temperatures studied. Dependences of MCE on temperature had weak maxima at 298 K at all magnetic induction values. The disturbance of the intermolecular hydrogen-bonding of hydroxyl groups is one of probable reasons for such dependences type. MCE values increased under the palmitoyl substituent incorporation into one of the phenol groups at all temperatures. The heat capacity of the studied complexes rose slightly with temperature growth. Dependences of the heat capacity on temperature showed that the magnetic component of the heat capacity did not appear due to the presence of the manganese atom acting as a paramagnetic center in complexes 1, 2, and 3. The relation between the complexes structure and their magnetothermal properties was analyzed. It was justified that the changes of magnetothermal properties were caused by electronic substitution effects and, to an even greater degree, by the conditions of intermolecular hydrogen bonds formation in the paramagnetic materials.

  2. Molecular dynamics in supercooled di-isobutyl phthalate close to the glass transition

    NASA Astrophysics Data System (ADS)

    Suchanski, W.; Jurga, S.; Pakula, T.; Paluch, M.; Ziolo, J.

    2000-11-01

    The dynamics of the ?-relaxation in a glass-forming low-molecular-weight system, di-isobutyl phthalate (DIBP), has been studied by means of dielectric, nuclear magnetic and mechanical spectroscopies. By using these techniques we have covered a wide timescale ranging from 10-11 to 102 s. Vogel-Fulcher correlation time behaviour and the Davidson-Cole distribution function make possible a simultaneous fitting of T1, the nuclear Overhauser enhancement (NOE) factor and dielectric data over the temperature range (Tg-4 K)

  3. CURious Variables Experiment (CURVE): CCD photometry of active dwarf nova DI Ursae Majoris

    NASA Astrophysics Data System (ADS)

    Rutkowski, A.; Olech, A.; Wiśniewski, M.; Pietrukowicz, P.; Pala, J.; Poleski, R.

    2009-04-01

    Context: We report an analysis of photometric behaviour of DI UMa, an extremely active dwarf nova. The observational campaign (completed in 2007) covers five superoutbursts and four normal outbursts. Aims: We examined principal parameters of the system to understand peculiarities of DI UMa, and other active cataclysmic variables. Methods: Based on precise photometric measurements, temporal light curve behaviour, O-C analysis, and power spectrum analysis, we investigated physical parameters of the system. Results: We found that the period of the supercycle now equals 31.45 ± 0.3 days. Observations during superoutbursts infer that the period of superhumps equals P_sh = 0.055318(11) days (79.66± 0.02 min). During quiescence, the light curve reveals a modulation of period P_orb = 0.054579(6) days (78.59 ± 0.01 min), which we interpret as the orbital period of the binary system. The values obtained allowed us to determine a fractional period excess of 1.35% ± 0.02%, which is surprisingly small compared to the usual value for dwarf novae (2%-5%). A detailed O-C analysis was performed for two superoutbursts with the most comprehensive coverage. In both cases, we detected an increase in the superhump period with a mean rate of dot P/P_sh = 4.4(1.0)× 10-5. Conclusions: Based on these measurements, we confirm that DI UMa is probably a period bouncer, an old system that reached its period minimum a long time ago, has a secondary that became a degenerate brown dwarf, the entire system evolving now toward longer periods. DI UMa is an extremely interesting object because we know only one more active ER UMa star with similar characteristics (IX Dra). Photometric data are only available in electronic form at the CDS via anonymous ftp to cdsarc.u-strasbg.fr (130.79.128.5) or via http://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/497/437

  4. Psychoanalytic and musical perspectives on shame in Donizetti's Lucia Di Lammermoor.

    PubMed

    Nagel, Julie Jaffee

    2008-06-01

    Two disciplines, psychoanalysis and music, are synthesized here with an eye to the origins and vicissitudes of shame and guilt as seen in the emotional disintegration of the eponymous heroine of Donizetti's opera Lucia di Lammermoor. Lucia's affects and her intrapsychic and interpersonal dynamics are heard in the music itself. A psychoanalytic and musical analysis of the opera, taking Lucia's dynamics as a quasi-substitute for clinical material, illuminates the intersections between certain theoretical aspects of the two disciplines. Both manifest and latent themes are expressed through the music of Donizetti's score. PMID:18515706

  5. Method for separating mono- and di-octylphenyl phosphoric acid esters

    DOEpatents

    Arnold, Jr., Wesley D.

    1977-01-01

    A method for separating mono-octylphenyl phosphoric acid ester and di-octylphenyl phosphoric acid ester from a mixture thereof comprises reacting the ester mixture with a source of lithium or sodium ions to form a mixture of the phosphate salts; contacting the salt mixture with an organic solvent which causes the dioctylphenyl phosphate salt to be dissolved in the organic solvent phase and the mono-octylphenyl phosphate salt to exist in a solid phase; separating the phases; recovering the phosphate salts from their respective phases; and acidifying the recovered salts to form the original phosphoric acid esters.

  6. Improved di-p-xylylene polymer and apparatus and method for making the same

    DOEpatents

    Jahn, R.K.; Liepins, R.

    Solid di-para-xylyene dimer is sublimed in a sublimation furnace at approximately 100 to 200/sup 0/C and subsequently conducted to a pyrolysis furnace where it is pyrolyzed to the diradical p-xylylene monomer while in the vapor state at approximately 600 degrees C. The diradical monomer is then introduced into a deposition chamber for deposition onto a suitable substrate. The deposition chamber includes electrodes for producing a low pressure plasma through which the diradical monomer passes prior to deposition. The interaction of the diradical monomer with the low pressure plasma results in the formation of poly-p-xylyene film which is exceptionally hard and thermally stable.

  7. An elegant microwave assisted one-pot synthesis of di(α-aminophosphonate) pesticides.

    PubMed

    Chandra Sekhar Reddy, Gangireddy; Radha Rani, Chinthaparthi; Veera Narayana Reddy, Mudumala; Suresh Reddy, Cirandur

    2014-11-01

    A new class of di(α-aminophosphonate) pesticides were prepared by the Kabachnik-Fields reaction under solvent- and catalyst-free conditions with microwave irradiation, and the products were obtained in good-to-excellent yields at shorter reaction time. These compounds were characterized by IR, (1)H, (13)C, (31)P NMR, and mass spectral data. Among them, compounds 4f, 4c, and 4h showed good pesticidal activity against Spodoptera litura, with 92.6, 91.3, and 89.3% mortality. PMID:25142415

  8. Structure of the capsular polysaccharide of Acinetobacter baumannii ACICU containing di-N-acetylpseudaminic acid.

    PubMed

    Senchenkova, Sof'ya N; Shashkov, Alexander S; Shneider, Mikhail M; Arbatsky, Nikolay P; Popova, Anastasiya V; Miroshnikov, Konstantin A; Volozhantsev, Nikolay V; Knirel, Yuriy A

    2014-06-01

    Capsular polysaccharide was isolated by the phenol-water extraction of Acinetobacter baumannii ACICU cells and studied by sugar analysis, partial acid hydrolysis, and 1D and 2D (1)H and (13)C NMR spectroscopy. The polysaccharide was found to contain 5,7-diacetamido-3,5,7,9-tetradeoxy-l-glycero-l-manno-non-2-ulosonic or di-N-acetylpseudaminic acid (Pse5Ac7Ac), and the following structure of the branched tetrasaccharide repeating unit was established: The genes present in the polysaccharide gene cluster of A. baumannii ACICU are appropriate to the structure established. PMID:24785392

  9. Sponsor gnomonici di 2000 anni fa nelle Dolomiti e a Pompei

    NASA Astrophysics Data System (ADS)

    del Favero, Enrico

    2003-01-01

    The author describes two memorial tablets of the Roman age, probably dating back to the first Century AD, which were discovered in Belluno province, in the towns of Valle di Cadore and Castellavazzo. They are concerned with sundials donated to the local communities by coeval sponsors. After brief recalling how people measured the time during the Roman age, the meaning of a similar tablet found in Pompeii is examined. This last tablet is included - inter alia - in the Michael T. Bragg's website on Pompeii, which has been found thanks to the so-called Roth's sundials list.

  10. Crystal structure of 3-(di­ethyl­amino)­phenol

    PubMed Central

    Golen, James A.; McDonald, Kyle J.; Manke, David R.

    2015-01-01

    The title compound, C10H15NO, has two mol­ecules in the asymmetric unit. Each mol­ecule has a near-planar C8NO unit excluding H atoms and the terminal methyl groups on the di­ethyl­amino groups, with mean deviations from planarity of 0.036 and 0.063 Å. In the crystal, hydrogen bonding leads to four-membered O—H⋯O—H⋯O—H·· rings. No π–π inter­actions were observed in the structure. PMID:26870505

  11. Transfert radiatif entre une petite particule et un diélectrique: application au chauffage local

    NASA Astrophysics Data System (ADS)

    Mulet, J.-P.; Joulain, K.; Carminati, R.; Greffet, J. J.

    2002-06-01

    nous montrons dans cette étude que le transfert radiatif entre une particule de taille nanométrique et un diélectrique petit être très important lorsque les distances mises en jeu sont petites devant la longueur d'onde caractéristique du rayonnement thermique. Ce transfert peut devenir dominant lorsque les matériaux utilisés sont polaires. Nous discuterons de la possibilité d'appliquer ces résultats au chauffage local dans les nano-structures.

  12. Uptake of di-(2-ethylhexyl) phthalate of vegetables from plastic film greenhouses.

    PubMed

    Fu, Xiaowei; Du, Qizhen

    2011-11-01

    Uptake of di-(2-ethylhexyl) phthalate (DEHP) of nine vegetables including potherb mustard, bok choy, celery, spinach, cabbage, leaf of tube, lettuce, garlic, and edible amaranth in plastic film greenhouses with different plastic films, film thickness, greenhouse age, and greenhouse height was studied. The results showed that the higher the DEHP content of film, the thicker the film, the lower the height of the greenhouse, and the younger the age of the greenhouse were, the higher the DEHP concentration of vegetables was. The results afford significant information for production of safe vegetables with low level DEHP contamination. PMID:21958198

  13. Chemical dynamics and reverse saturable absorption in di-furfuryl ether solutions

    NASA Astrophysics Data System (ADS)

    Mendonça, C. R.; Batista, P. S.; de Souza, M. F.; Zilio, S. C.

    2001-08-01

    We report on the chemical dynamics and nonlinear optical absorption of di-furfuryl ether (DFE) solutions. DFE molecules were derivatized from the room temperature furfuryl alcohol self-reaction, whose reaction kinetics was investigated with the Z-scan technique and laser-induced fluorescence. These molecules are shown to exhibit a pronounced reverse saturable absorption process. The magnitude of the excited-state absorption cross-sections and the intersystem crossing lifetime have been evaluated with 8 ns pulses at 532 nm.

  14. Structural and spectroscopic investigation on a new potentially bioactive di-hydrazone containing thiophene heterocyclic rings

    NASA Astrophysics Data System (ADS)

    Nogueira, Vanessa de S.; Ramalho Freitas, Maria Clara; Cruz, Wellington S.; Ribeiro, Tatiana S.; Resende, Jackson A. L. C.; Rey, Nicolás A.

    2016-02-01

    Hydrazones and several substituted hydrazones are associated with a broad spectrum of biological activities, as well as compounds containing the thiophene ring. In this context, a novel di-hydrazone derived from 2-thiophenecarboxylic acid hydrazide was synthesized and completely characterized by elemental analysis, XRD, FT-IR, Raman and UV-Vis spectroscopies, thermogravimetry, 1H NMR, 1H-1H COSY and 1H-1H ROESY. A preliminary in silico pharmacological evaluation was also performed in order to assess the performance of the new compound regarding some molecular properties relevant for a drug's pharmacokinetics in the human body.

  15. The iodosulfonamidation of peracetylated glycals revisited: access to 1,2-di-nitrogenated sugars.

    PubMed

    Gautier, François-Moana; Djedaïni-Pilard, Florence; Grandjean, Cyrille

    2011-04-01

    Iodosulfonamidation of peracetylated glycals was investigated using either a combination of N-iodosuccinimide/iodine or iodine chloride as a source of iodonium ion. 1,2-trans- and 1,2-cis-2-deoxy-2-iodo-1-sulfonamido hexoses were, respectively, obtained depending on the reagent system used. Both series of isomers were successfully converted to 1,2-di-nitrogenated compounds, for example, 1-azido-1,2-dideoxy-2-sulfonamido sugars, which are useful intermediates for the synthesis of N-linked glycoproteins or glycoconjugates. PMID:21333277

  16. Behavior of transplutonium elements on thin-layer silica gel using di-2-ethylhexylphosphoric acid

    SciTech Connect

    Molochnikova, N.P.; Myasoedov, B.F.

    1995-03-01

    The behavior of transplutonium elements (TPE) on thin-layer silica gel on domestic sorbphil thin-layer chromatography (TLC) plates is investigated using di-2-ethylhexylphosphoric acid (D2EHPA) solutions in HNO{sub 3} of various concentrations. Conditions are found for separating Bk(IV) from other TPE in solutions with [HNO{sub 3}] > 5 M and also for separating Bk(III) and Ce. Solutions of D2EHPA as the mobile phase are recommended for TLC identification of tracer amounts of different oxidation states Am in HNO{sub 3}.

  17. 5-Bromo-4-(3,5-di­bromo-2-hy­droxy­phen­yl)-2-(piperidin-1-yl)-1,3-di­thiol-2-ylium bromide

    PubMed Central

    Chirita, Paul; Hrib, Cristian G.; Birsa, Lucian M.

    2013-01-01

    In the title salt, C14H13Br3NOS2 +·Br−, synthesized by bromination of mesoionic 2-[2-(piperidin-1-yl)-1,3-di­thiol-2-ylium-4-yl]phenolate in glacial acetic acid, the dihedral angle between the 1,3-di­thiol­ium ring and the phenolic substituent ring is 45.9 (3)° due to the steric influence of the ortho-Br group on the 1,3-di­thiol­ium ring. The piperidine ring adopts a chair conformation. In the crystal, the cation and anion are linked by an O—H⋯Br hydrogen bond. PMID:24046659

  18. Crystal structure of tri­aqua­(2,6-di­methyl­pyrazine-κN 4)bis­(thio­cyanato-κN)manganese(II) 2,5-di­methyl­pyrazine disolvate

    PubMed Central

    Suckert, Stefan; Wöhlert, Susanne; Jess, Inke; Näther, Christian

    2015-01-01

    In the crystal structure of the title complex, [Mn(NCS)2(C6H8N2)(H2O)3]·2C6H8N2, the MnII cation is coordinated by two terminally N-bonded thio­cyanate anions, three water mol­ecules and one 2,6-di­methyl­pyrazine ligand within a slightly distorted N3O3 octa­hedral geometry; the entire complex mol­ecule is generated by the application of a twofold rotation axis. The asymmetric unit also contains an uncoordinating 2,5-di­methyl­pyrazine ligand in a general position. Obviously, the coordination to the 2,6-di­methyl­pyrazine ligand is preferred because coordination to the 2,5-di­methyl­pyrazine is hindered due to the bulky methyl group proximate to the N atom. The discrete complexes are linked by water-O—H⋯N(2,6-di­methyl­pyzazine/2,5-di­methyl­pyza­zine) hydrogen bonding, forming a three-dimensional network. In the crystal, mol­ecules are arranged in a way that cavities are formed in which unspecified, disordered solvent molecules reside. These were modelled employing the SQUEEZE routine in PLATON [Spek (2015 ▸). Acta Cryst. C71, 9–18]. The composition of the unit cell does not take into account the presence of the unspecified solvent. PMID:26870435

  19. Crystal structure of (μ-1,4-di-carb-oxy-butane-1,4-di-carboxyl-ato)bis-[bis-(tri-phenyl-phosphane)silver(I)] di-chloro-methane tris-olvate.

    PubMed

    Frenzel, Peter; Korb, Marcus; Lang, Heinrich

    2016-02-01

    The mol-ecular structure of the tetra-kis(tri-phenyl-phosphan-yl)disilver salt of butane-1,1,4,4-tetra-carb-oxy-lic acid, [Ag2(C8H8O8)(C18H15P)4]·3CH2Cl2, crystallizes with one and a half mol-ecules of di-chloro-methane in the asymmetric unit. The coordination complex exhibits an inversion centre through the central CH2-CH2 bond. The Ag(I) atom has a distorted trigonal-planar P2O coordination environment. The packing is characterized by inter-molecular T-shaped π-π inter-actions between the phenyl rings of the PPh3 substituents in neighbouring mol-ecules, forming a ladder-type superstructure parallel to [010]. These ladders are arranged in layers parallel to (101). Intra-molecular hydrogen bonds between the OH group and one O atom of the Ag-bonded carboxyl-ate group results in an asymmetric bidendate coordination of the carboxyl-ate moiety to the Ag(I) ion. PMID:26958391

  20. VizieR Online Data Catalog: Redshifts of ABCG209 galaxies (Mercurio+, 2003)

    NASA Astrophysics Data System (ADS)

    Mercurio, A.; Girardi, M.; Boschin, W.; Merluzzi, P.; Busarello, G.

    2003-03-01

    We study the internal dynamics of the rich galaxy cluster ABGC 209 on the basis of new spectroscopic and photometric data. The distribution in redshift shows that ABCG 209 is a well isolated peak of 112 detected member galaxies at z=0.209, characterised by a high value of the line-of-sight velocity dispersion, {sigma}v=1250-1400km/s, on the whole observed area (1h-1Mpc from the cluster center), that leads to a virial mass of M=1.6-2.2x1015h-1M{sun} within the virial radius, assuming the dynamical equilibrium. The data were collected at the ESO New Technology Telescope (NTT) with the ESO Multi Mode Instrument (EMMI) in October 2001. (1 data file).

  1. Design of PACs for high-performance photoresists (I): role of di-esterified PACs having hindered -OH groups

    NASA Astrophysics Data System (ADS)

    Hanawa, Ryotaro; Uetani, Yasunori; Hanabata, Makoto

    1992-06-01

    Steric hindrance on a ballast molecule causes selective esterification of -OH groups and provides novel di-esterified PACs having -OH group(s) with high selectivity. These novel PACs give photoresists higher sensitivities, (gamma) -values and resolutions, than those of fully esterified PACs. Also, these novel PACs provide scum-free patterns. Comparison of dissolution properties of a novel di-esterified PAC having a sterically hindered -OH with those of a di-esterified PAC suggests that the presence of -OH enhances dissolution rates, but it does not change the slope of logR-logE plots. DRM's agitated development reduces a large (gamma) -value of a novel PAC observed in puddle development. On the other hand, (gamma) -values of fully esterified PACs were not affected by the change of development methods. This observation suggests significance of (gamma) - value evaluation by puddle development for the investigation of high performance PACs.

  2. Halimeda dominance in the coastal wedge of Pietra di Finale (Ligurian Alps, Italy): The role of trophic conditions

    NASA Astrophysics Data System (ADS)

    Brandano, Marco; Tomassetti, Laura; Frezza, Virgilio

    2015-05-01

    The Middle to Late Miocene mixed carbonate-siliciclastic coastal wedge of the Pietra di Finale, unconformably overlying the Ligurian Alps succession, displays a carbonate portion dominated by Halimeda and Porites fragments that fall in the photozoan assemblages. Photozoan assemblages typically develop under tropical and oligotrophic conditions, while hetorozoan assemblages tend to thrive in high-nutrient settings. The Pietra di Finale Formation shows, however, that high weathering and an increase of nutrient inputs related to Alpine uplift and humid climatic conditions promoted Halimeda over the seagrass carbonate factory in the photic zone. The successful Halimeda proliferation was due to its efficient competition for nutrients, especially nitrogen. Thus, the Pietra di Finale Formation represents an interesting, counter-intuitive example in which increased nutrient concentrations promoted, instead of inhibited, a photozoan over a seagrass-related heterozoan carbonate production.

  3. High-Throughput Quantitative Proteomics Enabled by Mass Defect-Based 12-Plex DiLeu Isobaric Tags.

    PubMed

    Frost, Dustin C; Li, Lingjun

    2016-01-01

    Isobaric labeling has become a popular technique for high-throughput, mass spectrometry (MS)-based relative quantification of peptides and proteins. However, widespread use of the approach for large-scale proteomics applications has been limited by the high cost of commercial isobaric tags. To address this, we have developed our own N,N-dimethyl leucine (DiLeu) multiplex isobaric tags as a cost-effective alternative that can be synthesized with ease using readily available isotopic reagents. When paired with high-resolution tandem mass (MS (n) ) acquisition, mass defect-based DiLeu isobaric tags allow relative quantification of up to twelve samples in a single liquid chromatography (LC)-MS(2) experiment. Herein, we present detailed methods for synthesis of 12-plex DiLeu isobaric tags, labeling of complex protein digest samples, analysis by high-resolution nanoLC-MS (n) , and processing of acquired data. PMID:26867744

  4. A novel combined WDM-PON with a single shared DI using downlink DPSK and uplink remodulated OOK signals

    NASA Astrophysics Data System (ADS)

    Zhang, Hongguang; Cheng, Xiaofei; Xu, Zhaowen; Yeo, Yong-Kee

    2012-03-01

    We propose a novel downlink optical carrier remodulated wavelength-division-multiplexed passive optical network (WDM-PON) architecture, in which two WDM-PONs whose wavelength locate in different wavebands share a single delay interferometer (DI) in remote node (RN) to demodulate the downlink data simultaneously. 10-Gb/s downlink differential phase-shift-keying (DPSK) signal and 1.25-Gb/s remodulated uplink On-Off keying (OOK) signal are generated and measured. Experiment results show that crosstalk between the two WDM-PONs is negligible even though the two PONs share a single DI. With our novel scheme, the single DI can be shared by more users in different PONs, which can reduce the cost of optical network unit (ONU). Meanwhile, Rayleigh backscattering noise is eliminated by combining these two PONs with different wavebands.

  5. Degradation pathway of 2,5-di-tert-butyl-1,4-dimethoxybenzene at high potential.

    SciTech Connect

    Chen, Z.; Amine, K.; Chemical Engineering

    2007-01-01

    2,5-Di-tert-butyl-1,4-dimethoxybenzene is a redox shuttle for overcharge protection of LiFePO{sub 4}-based lithium-ion batteries with a working potential lower than 4.2 V versus Li{sup +}/Li. However, an irreversible decomposition occurs when the working potential is higher than 4.2 V versus Li{sup +}/Li. 2,3,5,6-Tetrafluoro-1,4-di-tert-butoxybenzene was also investigated as a model molecule to further understand the possible degradation pathway of 2,5-di-tert-butyl-1,4-dimethxybenzene. The experimental results strongly suggest that the irreversible reaction be related to the decomposition of OC bond in alkoxy substitution groups.

  6. Mutation in the C-Di-AMP Cyclase dacA Affects Fitness and Resistance of Methicillin Resistant Staphylococcus aureus

    PubMed Central

    Dengler, Vanina; McCallum, Nadine; Kiefer, Patrick; Christen, Philipp; Patrignani, Andrea; Vorholt, Julia A.; Berger-Bächi, Brigitte; Senn, Maria M.

    2013-01-01

    Faster growing and more virulent strains of methicillin resistant Staphylococcus aureus (MRSA) are increasingly displacing highly resistant MRSA. Elevated fitness in these MRSA is often accompanied by decreased and heterogeneous levels of methicillin resistance; however, the mechanisms for this phenomenon are not yet fully understood. Whole genome sequencing was used to investigate the genetic basis of this apparent correlation, in an isogenic MRSA strain pair that differed in methicillin resistance levels and fitness, with respect to growth rate. Sequencing revealed only one single nucleotide polymorphism (SNP) in the diadenylate cyclase gene dacA in the faster growing but less resistant strain. Diadenylate cyclases were recently discovered to synthesize the new second messenger cyclic diadenosine monophosphate (c-di-AMP). Introduction of this mutation into the highly resistant but slower growing strain reduced resistance and increased its growth rate, suggesting a direct connection between the dacA mutation and the phenotypic differences of these strains. Quantification of cellular c-di-AMP revealed that the dacA mutation decreased c-di-AMP levels resulting in reduced autolysis, increased salt tolerance and a reduction in the basal expression of the cell wall stress stimulon. These results indicate that c-di-AMP affects cell envelope-related signalling in S. aureus. The influence of c-di-AMP on growth rate and methicillin resistance in MRSA indicate that altering c-di-AMP levels could be a mechanism by which MRSA strains can increase their fitness levels by reducing their methicillin resistance levels. PMID:24013956

  7. Effects of maternal exposure to di(2-ethylhexyl)phthalate (DEHP) during pregnancy on susceptibility to neonatal asthma

    SciTech Connect

    Shin, In-Sik; Lee, Mee-Young; Cho, Eun-Sang; Choi, Eun-young; Son, Hwa-Young; Lee, Kyoung-Youl

    2014-02-01

    Di(2-ethylhexyl) phthalate (DEHP) is used as a plasticizer and is widely dispersed in the environment. In this study, we investigated the effects of maternal exposure to DEHP during pregnancy on neonatal asthma susceptibility using a murine model of asthma induced by ovalbumin (OVA). Pregnant BALB/c mice received DEHP from gestation day 13 to lactation day 21. Their offspring were sensitized on postnatal days (PNDs) 9 and 15 by intraperitoneal injection of 0.5 μg OVA with 200 μg aluminum hydroxide. On PNDs 22, 23 and 24, live pups received an airway challenge of OVA for 30 min. Offspring from pregnant mice that received DEHP showed reductions in inflammatory cell count, interleukin (IL)-4, IL-13, and eotaxin in their bronchoalveolar lavage fluid and in total immunoglobulin E and OVA-specific IgE in their plasma compared with offspring from pregnant mice that did not receive DEHP treatment. These results were consistent with histological analysis and immunoblotting. Maternal exposure to DEHP reduces airway inflammation and mucus production in offspring, with a decrease in inducible nitric oxide synthase (iNOS) in the lung tissue. This study suggests that maternal exposure to DEHP during pregnancy reduces asthmatic responses induced by OVA challenge in offspring. These effects were considered to be closely related to the suppression of Th2 immune responses and iNOS expression. - Highlights: • Maternal exposure to di(2-ethylhexyl)phthalate reduces asthmatic response in pups. • Di(2-ethylhexyl)phthalate reduces eosinophilia induced by ovalbumin exposure. • Di(2-ethylhexyl)phthalate reduces T-helper type 2 cytokine production. • Di(2-ethylhexyl)phthalate attenuates airway inflammation and mucus production. • Di(2-ethylhexyl)phthalate suppresses inducible nitric oxide synthase in lung tissue.

  8. The synthetic cationic lipid diC14 activates a sector of the Arabidopsis defence network requiring endogenous signalling components.

    PubMed

    Cambiagno, Damián Alejandro; Lonez, Caroline; Ruysschaert, Jean-Marie; Alvarez, María Elena

    2015-12-01

    Natural and synthetic elicitors have contributed significantly to the study of plant immunity. Pathogen-derived proteins and carbohydrates that bind to immune receptors, allow the fine dissection of certain defence pathways. Lipids of a different nature that act as defence elicitors, have also been studied, but their specific effects have been less well characterized, and their receptors have not been identified. In animal cells, nanoliposomes of the synthetic cationic lipid 3-tetradecylamino-tert-butyl-N-tetradecylpropionamidine (diC14) activate the TLR4-dependent immune cascade. Here, we have investigated whether this lipid induces Arabidopsis defence responses. At the local level, diC14 activated early and late defence gene markers (FRK1, WRKY29, ICS1 and PR1), acting in a dose-dependent manner. This lipid induced the salicylic acid (SA)-dependent, but not jasmonic acid (JA)-dependent, pathway and protected plants against Pseudomonas syringae pv. tomato (Pst), but not Botrytis cinerea. diC14 was not toxic to plant or pathogen, and potentiated pathogen-induced callose deposition. At the systemic level, diC14 induced PR1 expression and conferred resistance against Pst. diC14-induced defence responses required the signalling protein EDS1, but not NDR1. Curiously, the lipid-induced defence gene expression was lower in the fls2/efr/cerk1 triple mutant, but still unchanged in the single mutants. The amidine headgroup and chain length were important for its activity. Given the robustness of the responses triggered by diC14, its specific action on a defence pathway and the requirement for well-known defence components, this synthetic lipid is emerging as a useful tool to investigate the initial events involved in plant innate immunity. PMID:25727690

  9. Alpha-COP can discriminate between distinct, functional di-lysine signals in vitro and regulates access into retrograde transport.

    PubMed

    Schröder-Köhne, S; Letourneur, F; Riezman, H

    1998-12-01

    Emp47p is a yeast Golgi transmembrane protein with a retrograde, Golgi to ER transport di-lysine signal in its cytoplasmic tail. Emp47p has previously been shown to recycle between the Golgi complex and the ER and to require its di-lysine signal for Golgi localization. In contrast to other proteins with di-lysine signals, the Golgi-localization of Emp47p has been shown to be preserved in ret1-1 cells expressing a mutant alpha-COP subunit of coatomer. Here we demonstrate by sucrose gradient fractionation and immunofluorescence analysis that recycling of Emp47p was unimpaired in ret1-1. Furthermore we have characterized three new alleles of ret1 and showed that Golgi localization of Emp47p was intact in cells with those mutant alleles. We could correlate the ongoing recycling of Emp47p in ret1-1 with preserved in vitro binding of coatomer from ret1-1 cells to immobilized GST-Emp47p-tail fusion protein. As previously reported, the di-lysine signal of Wbp1p was not recognized by ret1-1 mutant coatomer, suggesting a possible role for alpha-COP in the differential binding to distinct di-lysine signals. In contrast to results with alpha-COP mutants, we found that Emp47p was mislocalised to the vacuole in mutants affecting beta'-, gamma-, delta-, and zeta-COP subunits of coatomer and that the mutant coatomer bound neither to the Emp47p nor to the Wbp1p di-lysine signal in vitro. Therefore, the retrograde transport of Emp47p displayed a differential requirement for individual coatomer subunits and a special role of alpha-COP for a particular transport step in vivo. PMID:9811561

  10. A new volar plate DiPhos-RM for fixation of distal radius fracture: preliminary report.

    PubMed

    Tarallo, Luigi; Mugnai, Raffaele; Adani, Roberto; Catani, Fabio

    2013-03-01

    We analyzed the efficiency of a new plate DiPhos-RM in CFR-PEEK [carbon-fiber-reinforced poly (etheretherketone)] for the volar fixation of distal radius fractures. The new plate's composition has the advantage of x-ray absolute transparency, therefore allowing to monitor the healing of the fracture. The desired combination of high strength and low rigidity is obtained through the use of the polymer composites CFR-PEEK. In this preliminary study (from March 2012 to June 2012), 10 cases of intra-articular distal radius fractures were treated with DiPhos-RM produced by Lima Corporate (Italy). The fractures were classified according to the AO classification, 4 fractures were type C1, 3 type C2, and 3 were A2. A preoperative computed tomography scan was carried out in all patients. One patient also underwent a postoperative computed tomography scan. Grip strength, range of motion, and DASH score were evaluated at follow-up. There were no cases of hardware failure. Specifically, no loss of position or alignment of fixed-angle locking screws or breakage of the plate were observed. Radiographic union was present at an average of 6 weeks (range, 5 to 8 wk). The overall preliminary experience with this new plate is favorable. The new plate is easy to apply and provides the surgeon dual options of fixed-angle or variable-angle screws. It was rigid enough to maintain the reduction also in AO type C articular fractures. PMID:23423235

  11. Effects of triangular flow on di-hadron azimuthal correlations in relativistic heavy ion collisions

    SciTech Connect

    Xu Jun; Ko, Che Ming

    2011-02-15

    Using the AMPT model for relativistic heavy ion collisions, we have studied the di-hadron azimuthal angular correlations triggered by emitted jets in Au+Au collisions at center-of-mass energy {radical}(s{sub NN})=200 GeV and impact parameter b=8 fm. A double-peak structure for the associated particles at the away side of trigger particles is obtained after subtracting background correlations due to the elliptic flow. Both the near-side peak and the away-side double peaks in the azimuthal angular correlations are, however, significantly suppressed (enhanced) in events of small (large) triangular flow or triangularity in the initial collision geometry as a result of fluctuations. After subtraction of background correlations due to the triangular flow, the away-side double peaks change into a single peak with broad shoulders on both sides. The away side of the di-hadron correlations becomes essentially a single peak after further subtraction of higher-order flows.

  12. Nitric oxide modulates bacterial biofilm formation through a multicomponent cyclic-di-GMP signaling network.

    PubMed

    Plate, Lars; Marletta, Michael A

    2012-05-25

    Nitric oxide (NO) signaling in vertebrates is well characterized and involves the heme-nitric oxide/oxygen-binding (H-NOX) domain of soluble guanylate cyclase as a selective NO sensor. In contrast, little is known about the biological role or signaling output of bacterial H-NOX proteins. Here, we describe a molecular pathway for H-NOX signaling in Shewanella oneidensis. NO stimulates biofilm formation by controlling the levels of the bacterial secondary messenger cyclic diguanosine monophosphate (c-di-GMP). Phosphotransfer profiling was used to map the connectivity of a multicomponent signaling network that involves integration from two histidine kinases and branching to three response regulators. A feed-forward loop between response regulators with phosphodiesterase domains and phosphorylation-mediated activation intricately regulated c-di-GMP levels. Phenotypic characterization established a link between NO signaling and biofilm formation. Cellular adhesion may provide a protection mechanism for bacteria against reactive and damaging NO. These results are broadly applicable to H-NOX-mediated NO signaling in bacteria. PMID:22542454

  13. Coordinated regulation of accessory genetic elements produces cyclic di-nucleotides for Vibrio cholerae virulence

    PubMed Central

    Davies, Bryan W.; Bogard, Ryan W.; Young, Travis S.; Mekalanos, John J.

    2013-01-01

    SUMMARY The function of the Vibrio 7th pandemic island-1 (VSP-1) in cholera pathogenesis has remained obscure. Utilizing ChIP-seq and RNA-seq to map the regulon of the master virulence regulator ToxT, we identify a TCP island encoded small RNA that reduces the expression of a previously unrecognized VSP-1 encoded transcription factor termed VspR. VspR modulates the expression of several VSP-1 genes including one that encodes a novel class of di-nucleotide cyclase (DncV), which preferentially synthesizes a previously undescribed hybrid cyclic AMP-GMP molecule. We show that DncV is required for efficient intestinal colonization and downregulates V. cholerae chemotaxis, a phenotype previously associated with hyperinfectivity. This pathway couples the actions of previously disparate genomic islands, defines VSP-1 as a pathogenicity island in V. cholerae and implicates its occurrence in 7th pandemic strains as a benefit for host adaptation through the production of a regulatory cyclic di-nucleotide. PMID:22500802

  14. Di-Isocyanate Crosslinked Aerogels with 1, 6-Bis (Trimethoxysilyl) Hexane Incorporated in Silica Backbone

    NASA Technical Reports Server (NTRS)

    Vivod, Stephanie L.; Meador, Mary Ann B.; Nguyen, Baochau N.; Quade, Derek; Randall, Jason; Perry, Renee

    2008-01-01

    Silica aerogels are desirable materials for many applications that take advantage of their light weight and low thermal conductivity. Addition of a conformal polymer coating which bonds with the amine decorated surface of the silica network improves the strength of the aerogels by as much as 200 times. Even with vast improvement in strength they still tend to undergo brittle failure due to the rigid silica backbone. We hope to increase the flexibility and elastic recovery of the silica based aerogel by altering the silica back-bone by incorporation of more flexible hexane links. To this end, we investigated the use of 1,6-bis(trimethoxysilyl)hexane (BTMSH), a polysilsesquioxane precursor3, as an additional co-reactant to prepare silica gels which were subsequently cross-linked with di-isocyanate. Previously, this approach of adding flexibility by BTMSH incorporation was demonstrated with styrene cross-linked aerogels. In our study, we varied silane concentration, mol % of silicon from BTMSH and di-isocyanate concentration by weight percent to attempt to optimize both the flexibility and the strength of the aerogels.

  15. Surface microbiota analysis of Taleggio, Gorgonzola, Casera, Scimudin and Formaggio di Fossa Italian cheeses.

    PubMed

    Fontana, Cecilia; Cappa, Fabrizio; Rebecchi, Annalisa; Cocconcelli, Pier Sandro

    2010-04-15

    The composition of the bacterial consortia of the smear Italian cheeses and their role on quality and safety is still poorly understood. The objective of this study was to identify and characterize the bacterial communities present on the surface of five traditional Italian cheeses, Casera Valtellina, Scimudin, Formaggio di Fossa, Gorgonzola and Taleggio. DGGE analysis performed using total DNA obtained from cheese surfaces enabled us to identify the dominant bacterial populations. Bands showing different intensity and identified as Staphylococcus, Micrococcus, Psychrobacter, Enterococcus and Brevibacterium species were detected on the surface of cheeses. The cluster analysis showed that Gorgonzola, Taleggio and Formaggio di Fossa cheeses present high similarity in their surface bacterial composition while major differences in the DGGE profiles were observed in Scimudin and Casera. The molecular taxonomical identification among the Gram positive isolates, reveals the presence of the following bacterial genera: Staphylococcus, Micrococcus, Macrococcus, Enterococcus, Lactobacillus, Carnobacterium, Leuconostoc, Brevibacterium, Corynebacterium, Brochothrix, Bacillus. The combination of culture dependent and independent techniques allowed us to obtain information about the bacterial species covering the surface of five different traditional Italian cheeses. PMID:20167385

  16. Crystal structure of 2,6-di­amino­pyridinium chloride

    PubMed Central

    Mastalir, Matthias; Schroffenegger, Martina; Stöger, Berthold; Weil, Matthias; Kirchner, Karl

    2016-01-01

    The asymmetric unit of the title salt, C5H8N3 +·Cl−, comprises one half of the 2,6-di­amino­pyridinium cation (the other half being completed by the application of mirror symmetry) and one Cl− counter-anion, also located on the mirror plane. The amino N atom shows a significant pyramidalization, with a dihedral angle of 30.4 (14)° between the least-squares planes of the amino group and the non-H atoms of the 2,6-di­amino­pyridinium moiety. In the crystal, the cationic mol­ecules and Cl− counter-anions are arranged in sheets parallel to (001) consisting of alternating polar and non-polar parts associated with the the Cl− anions, pyridinium and amino moieties, and the pyridine rings, respectively. N—H⋯Cl inter­actions within the polar part, as well as slipped π–π inter­actions in the non-polar part, help to establish the three-dimensional network. PMID:27006800

  17. Crystal structure of 2,6-di-amino-pyridinium chloride.

    PubMed

    Mastalir, Matthias; Schroffenegger, Martina; Stöger, Berthold; Weil, Matthias; Kirchner, Karl

    2016-03-01

    The asymmetric unit of the title salt, C5H8N3 (+)·Cl(-), comprises one half of the 2,6-di-amino-pyridinium cation (the other half being completed by the application of mirror symmetry) and one Cl(-) counter-anion, also located on the mirror plane. The amino N atom shows a significant pyramidalization, with a dihedral angle of 30.4 (14)° between the least-squares planes of the amino group and the non-H atoms of the 2,6-di-amino-pyridinium moiety. In the crystal, the cationic mol-ecules and Cl(-) counter-anions are arranged in sheets parallel to (001) consisting of alternating polar and non-polar parts associated with the the Cl(-) anions, pyridinium and amino moieties, and the pyridine rings, respectively. N-H⋯Cl inter-actions within the polar part, as well as slipped π-π inter-actions in the non-polar part, help to establish the three-dimensional network. PMID:27006800

  18. The explosion of the bolide over Lugo DI Romagna (Italy) on 19 January 1993

    NASA Astrophysics Data System (ADS)

    Cevolani, G.

    1994-09-01

    A spectacular fireball was observed crossing Northern Italy from SE to NW on 19 January 1993, at about 00.33 h UT, ending with an explosion approximately over the city of Lugo di Romagna. Calculations on the fragmentation of the body were performed for an entry velocity of 25 km/s, a low-inclination of about 14-15 deg, and a material strength S = 10-50 MPa (Bronshten, V. A., 1983) valid for stony (and carbonaceous) chondrites, with heights of first fragmentation hbreak is less than or = 35-40 km. For estimated visual magnitudes Mv = -22 to -25 at the peak of the light-curve corresponding to values of an initial radius of 1.5-3 m (Hills, J. K. and Goda, 1993), a meteor luminosity ranging between 300 and 4000 GW is obtained, consistent with the radiant flux values obtained by the Stefan-Boltzmann law for a black-body temperature of tens of thousands degrees. The explosion of the bolide produced low-frequency (1.5-2 Hz) infrasonic waves which were monitored by a microseismic network of three stations near Ferrara and by regional seismic stations of the ING (Istituto Nazionale di Geofisica) at 20-60 km horizontal distances from the epicentre located in the stratosphere. Micronanalysis of recovered particles in the explosion zone, in the form of spherules of vaporized and recondensed material, reveals the relative importance of light chemical elements typical of soft structures.

  19. Crystal structure of the thermochromic bis-(di-ethyl-ammonium) tetra-chlorido-cuprate(II) complex.

    PubMed

    Aldrich, Emily P; Bussey, Katherine A; Connell, Jennifer R; Reinhart, Erin F; Oshin, Kayode D; Mercado, Brandon Q; Oliver, Allen G

    2016-01-01

    In the structure of the title complex salt, (Et2NH2)2[CuCl4], the asymmetric unit consists of four unique di-ethyl-ammonium cations and three unique tetra-chlorido-cuprate anions. Two of the three anions are located with their copper atoms on independent crystallographic twofold axes, while the remaining tetra-chlorido-cuprate is located at a general position of the ortho-rhom-bic space group P21212. Two of the three Cu atoms adopt a distorted square-planar/disphenoidal geometry and the third Cu atom has a regular square-planar coordination environment. The di-ethyl-ammonium cations form an extensive hydrogen-bonded network through N-H⋯Cl inter-actions with the tetra-chlorido-cuprate anions, resulting in a two-dimensional sheet-like hydrogen-bonded network parallel to the ab direction. The complex was observed to undergo a color shift from deep green at room temperature to pale yellow at temperatures above 328 K. PMID:26870581

  20. Di-hydrogen contact induced lattice instabilities and structural dynamics in complex hydride perovskites.

    PubMed

    Schouwink, P; Hagemann, H; Embs, J P; D'Anna, V; Černý, R

    2015-07-01

    The structural phase transitions occurring in a series of perovskite-type complex hydrides based on the tetrahydroborate anion BH4(-) are investigated by means of in situ synchrotron x-ray powder diffraction, vibrational spectroscopy, thermal methods and ab initio calculations in the solid state. Structural dynamics of the BH4 anion are followed with quasi-elastic neutron scattering. We show that unexpected temperature-induced lattice instabilities in perovskite-type ACa(BH4)3 (A = K, Rb, Cs) have their origin in close hydridic di-hydrogen contacts. The rich lattice dynamics lead to coupling between internal B-H vibrations and phonons, resulting in distortions in the high-temperature polymorph that are identical in symmetry to well-known instabilities in oxide perovskites, generally condensing at lower temperatures. It is found that anion-substitution BH4(-) <-> (X = Halide) can relax distortions in ACa(BH4)3 by eliminating coulomb repulsive H(-)···H(-) effects. The interesting nature of phase transition in ACa(BH4)3 enters an unexplored field of weak interactions in ceramic-like host lattices and is the principal motivation for this study. Close di-hydrogen contacts suggest new concepts to tailor crystal symmetries in complex hydride perovskites in the future. PMID:26076047

  1. Ionic environment and hydrogen bonding in di-ureasil ormolytes doped with lithium triflate

    NASA Astrophysics Data System (ADS)

    Nunes, S. C.; Bermudez, V. de Zea; Ostrovskii, D.; Carlos, L. D.

    2004-09-01

    Di-urea cross-linked sol-gel derived poly(oxyethylene) (POE)/siloxane hybrids (di-ureasils) doped with a wide concentration range of lithium triflate (LiCF 3SO 3) were studied by infrared and Raman spectroscopies with the primary objective of examining in detail the Li +/cross-link and hydrogen bonding interactions. Another goal of this work was to find additional data that confirmed previous conclusions regarding the Li +/polymer and Li +/anion bonding. Xerogels with ∞> n≥1 (where n, called salt composition, is the molar ratio OCH 2CH 2/Li +) were analyzed. The analysis of the 'amide I' and 'amide II' regions provided solid evidences that the Li + ions bond to the urea carbonyl oxygen atoms in the entire range of salt concentration studied. The changes detected in the CH 2 rocking region indicate that the alkali metal cations are also coordinated to the ether oxygen atoms of the POE chains at n≤20. Proofs of the formation of a POE/LiCF 3SO 3 crystalline compound at n≤10 were also found. The anionic configurations detected in the FT-IR SO 3 symmetric stretching region are in perfect agreement with those deduced from the FT-Raman spectra.

  2. Study of sol gel derived di-ureasils doped with zinc triflate

    NASA Astrophysics Data System (ADS)

    Nunes, S. C.; de Zea Bermudez, V.; Silva, M. M.; Smith, M. J.; Morales, E.; Sá Ferreira, R. A.; Carlos, L. D.; Rocha, J.

    2006-12-01

    Zinc triflate (Zn(CF 3SO 3) 2)-doped sol-gel derived di-urea cross-linked POE/siloxane ormolytes (designated as di-ureasils) with ∞>n⩾1 (where the salt content is expressed as n, the molar ratio of oxyethylene moieties to Zn 2+ ions) were investigated. The hybrids with n⩾5 are entirely amorphous; those with n>10 are thermally stable up to approximately 305 °C. The siliceous network of representative samples ( n=200 and 10) is essentially composed of (SiO) 3Si(CH 2)-environments and is thus highly branched. The distance between the structural units in samples with 200⩾n⩾10 and n⩽7 is 4.2 and 4.3 Å, respectively. The estimated interdomain distance is 11 and 13 Å for xerogels with 200⩾n⩾20 and n⩽10, respectively. At n=1 a crystalline POE/Zn(CF 3SO 3) 2 complex of unknown stoichiometry is formed. The conductivity maxima are located at n=60 ( 3×10 S cm) and n=20 ( 7×10 S cm) at 30 and 100 °C, respectively.

  3. Identification of a bacterial di-haem cytochrome c peroxidase from Methylomicrobium album BG8.

    PubMed

    Karlsen, O A; Larsen, Ø; Jensen, H B

    2010-09-01

    The nucleotide sequence of an open reading frame (corB) downstream of the copper-repressible CorA-encoding gene of the methanotrophic bacterium Methylomicrobium album BG8 was obtained by restriction enzyme digestion and inverse PCR. The amino acid sequence deduced from this gene showed significant sequence similarity to the surface-associated di-haem cytochrome c peroxidase (SACCP) previously isolated from Methylococcus capsulatus (Bath), including both c-type haem-binding motifs. Homology analysis placed this protein, phylogenetically, within the subfamily containing the M. capsulatus SACCP of the bacterial di-haem cytochrome c peroxidase (BCCP) family of proteins. Immunospecific recognition confirmed synthesis of the M. album CorB as a protein non-covalently associated with the outer membrane and exposed to the periplasm. corB expression is regulated by the availability of copper ions during growth and the protein is most abundant in M. album when grown at a low copper-to-biomass ratio, indicating an important physiological role of CorB under these growth conditions. corB was co-transcribed with the gene encoding CorA, constituting a copper-responding operon, which appears to be under the control of a sigma(54)-dependent promoter. M. album CorB is the second isolated member of the recently described subfamily of the BCCP family of proteins. So far, these proteins have only been described in methanotrophic bacteria. PMID:20576687

  4. A Conserved Di-Basic Motif of Drosophila Crumbs Contributes to Efficient ER Export.

    PubMed

    Kumichel, Alexandra; Kapp, Katja; Knust, Elisabeth

    2015-06-01

    The Drosophila type I transmembrane protein Crumbs is an apical determinant required for the maintenance of apico-basal epithelial cell polarity. The level of Crumbs at the plasma membrane is crucial, but how it is regulated is poorly understood. In a genetic screen for regulators of Crumbs protein trafficking we identified Sar1, the core component of the coat protein complex II transport vesicles. sar1 mutant embryos show a reduced plasma membrane localization of Crumbs, a defect similar to that observed in haunted and ghost mutant embryos, which lack Sec23 and Sec24CD, respectively. By pulse-chase assays in Drosophila Schneider cells and analysis of protein transport kinetics based on Endoglycosidase H resistance we identified an RNKR motif in Crumbs, which contributes to efficient ER export. The motif identified fits the highly conserved di-basic RxKR motif and mediates interaction with Sar1. The RNKR motif is also required for plasma membrane delivery of transgene-encoded Crumbs in epithelial cells of Drosophila embryos. Our data are the first to show that a di-basic motif acts as a signal for ER exit of a type I plasma membrane protein in a metazoan organism. PMID:25753515

  5. Probing a light CP-odd scalar in di-top-associated production at the LHC

    NASA Astrophysics Data System (ADS)

    Casolino, Mirkoantonio; Farooque, Trisha; Juste, Aurelio; Liu, Tao; Spannowsky, Michael

    2015-10-01

    CP-odd scalars are an integral part of many extensions of the Standard Model. Recently, electroweak-scale pseudoscalars have received increased attention in explaining the diffuse gamma-ray excess from the Galactic Centre. Elusive due to absence of direct couplings to gauge bosons, these particles receive only weak constraints from direct searches at LEP or searches performed during the first LHC runs. We investigate the LHC's sensitivity in probing a CP-odd scalar in the mass range 20 ≤ m_A ≤ 100 GeV via di-top-associated production using jet-substructure-based reconstruction techniques. We parameterise the scalar's interactions using a simplified model approach and relate the obtained upper limits to couplings within type-I and type-II 2HDMs as well as the NMSSM. We find that in di-top-associated production, experiments at the LHC can set tight limits on CP-odd scalars that fit the Galactic Centre excess. However, direct sensitivity to light CP-odd scalars from the NMSSM remains challenging.

  6. Distribution of di(2-ethylhexyl) phthalate and products in blood and blood components.

    PubMed Central

    Rock, G; Labow, R S; Tocchi, M

    1986-01-01

    In order to impart flexibility, plastic medical devices incorporate liquid plasticizers into their structure. Data from several laboratories, including ours, have shown that these compounds leach from blood bags and tubing during collection of blood, storage of various blood components and during kidney dialysis and cell and plasma apheresis procedures. After the plasticizer di(2-ethylhexyl) phthalate leaches from poly(vinyl chloride) blood packs, it is converted by a plasma enzyme to a more toxic metabolite, mono(2-ethylhexyl) phthalate. Blood fractionation products from outdated plasma contain mono(2-ethylhexyl) phthalate, the highest level being found in normal serum albumin. Recently, we have reported that di(2-ethylhexyl) phthalate actually binds to the red blood cell membrane and reduces its osmotic fragility. Current methods of red cells storage, which permit utilization up to 35 days after collection, are not possible without this membrane stabilization. Platelets are now stored for 5 days in the Fenwal PL 732 polyolefin bag. Although stated to be essentially free of liquid plasticizers, a significant level of leaching from this bag into the extracts of stored platelet concentrates was observed. PMID:3709456

  7. Listeria monocytogenes exopolysaccharide: origin, structure, biosynthetic machinery and c-di-GMP-dependent regulation.

    PubMed

    Kseo?lu, Volkan K; Heiss, Christian; Azadi, Parastoo; Topchiy, Elena; Gvener, Zehra T; Lehmann, Teresa E; Miller, Kurt W; Gomelsky, Mark

    2015-05-01

    Elevated levels of the second messenger c-di-GMP activate biosynthesis of an unknown exopolysaccharide (EPS) in the food-borne pathogen Listeria monocytogenes. This EPS strongly protects cells against disinfectants and desiccation, indicating its potential significance for listerial persistence in the environment and for food safety. We analyzed the potential phylogenetic origin of this EPS, determined its complete structure, characterized genes involved in its biosynthesis and hydrolysis and identified diguanylate cyclases activating its synthesis. Phylogenetic analysis of EPS biosynthesis proteins suggests that they have evolved within monoderms. Scanning electron microscopy revealed that L.?monocytogenes?EPS is cell surface-bound. Secreted carbohydrates represent exclusively cell-wall debris. Based on carbohydrate composition, linkage and NMR analysis, the structure of the purified EPS is identified as a ?-1,4-linked N-acetylmannosamine chain decorated with terminal ?-1,6-linked galactose. All genes of the pssA-E operon are required for EPS production and so is a separately located pssZ gene. We show that PssZ has an EPS-specific glycosylhydrolase activity. Exogenously added PssZ prevents EPS-mediated cell aggregation and disperses preformed aggregates, whereas an E72Q mutant in the presumed catalytic residue is much less active. The diguanylate cyclases DgcA and DgcB, whose genes are located next to pssZ, are primarily responsible for c-di-GMP-dependent EPS production. PMID:25662512

  8. Characterisation and cytomodulatory properties of peptides from Mozzarella di Bufala Campana cheese whey.

    PubMed

    De Simone, Carmela; Picariello, Gianluca; Mamone, Gianfranco; Stiuso, Paola; Dicitore, Alessandra; Vanacore, Daniela; Chianese, Lina; Addeo, Francesco; Ferranti, Pasquale

    2009-03-01

    Bioactive peptides are present in a latent state, encrypted within the amino acid sequence of milk proteins, requiring enzymatic proteolysis for their release. They can be produced by gastrointestinal digestion or food processing, thus they can be present in fermented milks, cheese and also in the by-products of dairy industry such as waste whey. The spectrum of biological activity covered by milk-derived peptides is extremely wide, including antibacterial, immunostimulating, antihypertensive, antithrombotic and opioid actions. However, the characterisation of milk-derived peptides with classical analytical methodologies is severely challenged by the complexity of the milk protein fraction and by the wide dynamic range of relative peptide abundance in both dairy products and by-products. Here we report the characterisation of the peptide fraction released in the whey during the different production stages of Mozzarella di Bufala Campana cheese. The peptide extracts were separated by RP HPLC and analysed by MS in order to identify the peptides produced and to trace the pathway of formation of potential bioactive peptides. The antioxidant properties and the modulatory effect on the cell cycle exerted by the peptide extracts were also studied in CaCo2 cell line. We found that a significant antiproliferative effect on CaCo2 was exerted by Mozzarella di Bufala waste whey peptides. PMID:19035578

  9. Revision Surgery in Permanent Patellar Dislocation in DiGeorge Syndrome

    PubMed Central

    Berruto, Massimo; Parente, Andrea; Ferrua, Paolo; Pasqualotto, Stefano; Uboldi, Francesco; Usellini, Eva

    2015-01-01

    A 29-year-old patient, suffering from DiGeorge syndrome, came to our attention with a history of persistent pain and patellar instability in the left knee after failure of arthroscopic lateral release and Elmslie-Trillat procedure. The patient was unable to walk without crutches and severely limited in daily living activities. Because of arthritic changes of the patellofemoral joint and the failure of previous surgeries it was decided to perform only an open lateral release and medial patellofemoral ligament (MPFL) reconstruction using a biosynthetic ligament in order to obtain patellofemoral stability. At one year post-op range of motion (ROM) was 0–120 with a firm end point at medial patellar mobilization; patella was stable throughout the entire ROM. All the scores improved and she could be able to perform daily activity without sensation of instability. Bilateral patellar subluxation and systemic hyperlaxity are characteristics of syndromic patients and according to literature can be also present in DiGeorge syndrome. MPFL reconstruction with lateral release was demonstrated to be the correct solution in the treatment of patellar instability in this complex case. The choice of an artificial ligament to reconstruct the MPFL was useful in this specific patient with important tissue laxity due to her congenital syndrome. PMID:26783479

  10. DiFX2: A more flexible, efficient, robust and powerful software correlator

    NASA Astrophysics Data System (ADS)

    Deller, A. T.; Brisken, W. F.; Phillips, C. J.; Morgan, J.; Alef, W.; Cappallo, R.; Middelberg, E.; Romney, J.; Rottmann, H.; Tingay, S. J.; Wayth, R.

    2011-02-01

    Software correlation, where a correlation algorithm written in a high-level language such as C++ is run on commodity computer hardware, has become increasingly attractive for small to medium sized and/or bandwidth constrained radio interferometers. In particular, many long baseline arrays (which typically have fewer than 20 elements and are restricted in observing bandwidth by costly recording hardware and media) have utilized software correlators for rapid, cost-effective correlator upgrades to allow compatibility with new, wider bandwidth recording systems and improve correlator flexibility. The DiFX correlator, made publicly available in 2007, has been a popular choice in such upgrades and is now used for production correlation by a number of observatories and research groups worldwide. Here we describe the evolution in the capabilities of the DiFX correlator over the past three years, including a number of new capabilities, substantial performance improvements, and a large amount of supporting infrastructure to ease use of the code. New capabilities include the ability to correlate a large number of phase centers in a single correlation pass, the extraction of phase calibration tones, correlation of disparate but overlapping sub-bands, the production of rapidly sampled filterbank and kurtosis data at minimal cost, and many more. The latest version of the code is at least 15% faster than the original, and in certain situations many times this value. Finally, we also present detailed test results validating the correctness of the new code.

  11. Electromagnetic methods to characterize the Savoia di Lucania waste dump (Southern Italy)

    NASA Astrophysics Data System (ADS)

    Bavusi, M.; Rizzo, E.; Lapenna, V.

    2006-11-01

    The aim of this work is the joint application and integration of non-invasive geoelectrical methods for studying the landfill of Savoia di Lucania (Southern Italy). This landfill for its engineering features and small dimensions (70 m × 30 m × 6 m) represents an optimal test site to assess a geophysical survey protocol for municipal solid waste landfills investigation and monitoring. The landfill of Savoia di Lucania has been built with a reinforced concrete material and coated with a high-density polyethylene (HDPE) liner. Three electrical resistivity tomographies (ERT), two self-potential (SP) map surveys and one induced polarization (IP) section have been performed, both in the surrounding area and inside the waste landfill. The geophysical investigations have well defined some buried boundaries of the landfill basin and localized the leachate accumulation zones inside the dumpsite. Comparison of our results with other engineering and geological investigations could be the key for evaluating the integrity of the HDPE liner. Finally, the joint use of the ERT, IP and SP methods seems to be a promising tool for studying and designing new monitoring systems able to perform a time-lapse analysis of waste landfill geometry and integrity.

  12. Identification of di-2-ethylhexyl terephthalate (DEHTP) metabolites using human liver microsomes for biomonitoring applications.

    PubMed

    Silva, Manori J; Samandar, Ella; Calafat, Antonia M; Ye, Xiaoyun

    2015-06-01

    Di-2-ethylhexyl terephthalate (DEHTP), a structural isomer of the plasticizer di-2-ethylhexyl phthalate (DEHP), is used in food packaging and medical devices, among other applications, and is a potential replacement for DEHP and other ortho-phthalate plasticizers. Identifying sensitive and specific biomarkers of DEHTP is necessary to assess humans' background exposure to DEHTP. Using mass spectrometry, we investigated the metabolism of DEHTP by human liver microsomes to identify in vitro DEHTP metabolites. We unequivocally identified terephthalic acid (TPA) and mono-2-ethylhydroxyhexyl terephthalate (MEHHTP), using authentic standards, and tentatively identified mono-2-ethylhexyl terephthalate (MEHTP) and two other oxidative metabolites of DEHTP: mono-2-ethyloxohexyl terephthalate (MEOHTP), and mono-2-ethyl-5-carboxypentyl terephthalate (MECPTP) from their mass spectrometry fragmentation patterns. We also evaluated the formation of in vitro metabolites of DEHP. DEHTP and DEHP produced similar metabolites, but their metabolite profiles differed considerably. DEHTP metabolized to form TPA, a metabolite of several terephthalates, as the major in vitro metabolite, followed by MEHTP, MEHHTP, MEOHTP and MECPTP. MEHTP, MEHHTP, MEOHTP and MECPTP, which are specific metabolites of DEHTP, may be suitable biomarkers for assessing exposure to DEHTP. Nonetheless, data on the urinary excretion fraction and temporal stability of these metabolites, among other considerations, are needed to demonstrate their utility as exposure biomarkers. PMID:25687528

  13. Revision Surgery in Permanent Patellar Dislocation in DiGeorge Syndrome.

    PubMed

    Berruto, Massimo; Parente, Andrea; Ferrua, Paolo; Pasqualotto, Stefano; Uboldi, Francesco; Usellini, Eva

    2015-01-01

    A 29-year-old patient, suffering from DiGeorge syndrome, came to our attention with a history of persistent pain and patellar instability in the left knee after failure of arthroscopic lateral release and Elmslie-Trillat procedure. The patient was unable to walk without crutches and severely limited in daily living activities. Because of arthritic changes of the patellofemoral joint and the failure of previous surgeries it was decided to perform only an open lateral release and medial patellofemoral ligament (MPFL) reconstruction using a biosynthetic ligament in order to obtain patellofemoral stability. At one year post-op range of motion (ROM) was 0-120 with a firm end point at medial patellar mobilization; patella was stable throughout the entire ROM. All the scores improved and she could be able to perform daily activity without sensation of instability. Bilateral patellar subluxation and systemic hyperlaxity are characteristics of syndromic patients and according to literature can be also present in DiGeorge syndrome. MPFL reconstruction with lateral release was demonstrated to be the correct solution in the treatment of patellar instability in this complex case. The choice of an artificial ligament to reconstruct the MPFL was useful in this specific patient with important tissue laxity due to her congenital syndrome. PMID:26783479

  14. Modeling of material erosion and redeposition for dedicated DiMES experiments on DIII-D

    NASA Astrophysics Data System (ADS)

    Ding, R.; Abrams, T.; Chrobak, C. P.; Guo, H. Y.; Snyder, P. B.; Chan, V. S.; Rudakov, D. L.; Stangeby, P. C.; Elder, J. D.; Tskhakaya, D.; Wampler, W. R.; Kirschner, A.; McLean, A. G.

    2015-11-01

    Erosion and redeposition of plasma facing materials is a key issue for high-power, long pulse tokamak operation. A series of experiments has been carried out on DIII-D in which well-characterized samples of different materials were exposed to divertor plasma using DiMES. Such experiments provide a good benchmark for PMI codes, such as ERO. It was found that the erosion and redeposition are strongly determined by the impurity content in the plasma and sheath properties near the surface. The principal experimental results (net erosion rate and profile, net/gross erosion ratio) are reproduced by ERO simulations to within the uncertainties, indicating that the controlling physics has likely been identified. New techniques suggested by modeling such as external biasing and local gas injection for suppressing material erosion are planned to be tested in DiMES/DIII-D experiments. Work supported by US DOE DE-FC02-04ER54698, DE-AC52-07NA27344, DE-AC04-94AL85000, DE-AC52-07NA27344.

  15. The DiViSA's Predictive Validity by Age: An Objective Online Test of Attention.

    PubMed

    Santacreu, J; Quiroga, M A

    2015-01-01

    The purpose of this study was to analyze the DiViSA's predictive validity in school-age children. To do so, two groups of school-age children were compared: one with low school achievement (N = 1,174), and one with typical development (N = 1,426). The obtained results show that: (1) in all grades, children with poor school performance exhibited lower levels of attention and task organization, greater hastiness, and made more commission errors; (2) the combination of variables that best differentiated between groups was not the same in all grades; (3) level of organization improved with age in the low-school-achievement group, and did not in the typical-development group; (4) the data regarding sensitivity (81% to 93%) and specificity (79% to 90%), for the first time computed for each grade separately, support the test's predictive validity in the grades we evaluated. The discussion focuses on the DiViSA test's usefulness in diagnosing attention problems. It is the first computerized test to include separate scores for: (a) how children complete the task (organization) and (2) the source of their errors (distraction or hastiness). PMID:26646471

  16. Ultrafast intramolecular charge transfer with strongly twisted aminobenzonitriles: 4-(di-tert-butylamino)benzonitrile and 3-(di-tert-butylamino)benzonitrile.

    PubMed

    Druzhinin, Sergey I; Dubbaka, Srinivas Reddy; Knochel, Paul; Kovalenko, Sergey A; Mayer, Peter; Senyushkina, Tamara; Zachariasse, Klaas A

    2008-04-01

    The newly synthesized aminobenzonitriles with two bulky amino substituents 4-(di-tert-butylamino)benzonitrile (DTABN) and 3-(di-tert-butylamino)benzonitrile (mDTABN) have strongly twisted amino groups in the ground state. From X-ray crystal analysis it is found that the amino twist angle theta of mDTABN equals 86.5 degrees , whereas a twist angle of around 75 degrees is deduced for DTABN from the extinction coefficient of its lowest-energy absorption band in n-hexane. Because of the electronic decoupling between the amino and benzonitrile groups caused by these large twist angles, the absorption of DTABN and mDTABN is relatively weak below 40000 cm-1, with extinction coefficients around 25 times smaller than those of the planar 4-(dimethylamino)benzonitrile (DMABN). DTABN as well as mDTABN undergo efficient intramolecular charge transfer (ICT) in the singlet excited state, in nonpolar (n-hexane) as well as in polar (acetonitrile) solvents. Their fluorescence spectra consist of an ICT emission band, without evidence for locally excited (LE) fluorescence. The occurrence of efficient ICT with mDTABN is different from the findings with all other N,N-dialkylaminobenzonitriles in the literature, for which ICT only appears with the para-derivative. From solvatochromic measurements, an ICT dipole moment of 17 D is determined for DTABN as well as for mDTABN, similar to that of DMABN. The picosecond fluorescence decays of DTABN (time resolution 3 ps) are effectively single exponential. Their decay time is equal to the ICT lifetime tau'0(ICT), which increases with solvent polarity from 0.86 ns in n-hexane to 3.48 ns in MeCN at 25 degrees C. The femtosecond excited-state absorption (ESA) spectra of DTABN in n-hexane and MeCN at 22 degrees C show a decay of the LE and a corresponding rise of the ICT absorption. The ICT reaction time is 70 fs in n-hexane and 60 fs in MeCN. DTABN and mDTABN may have a strongly twisted ICT state, similar to that of 6-cyanobenzoquinuclidine but different from that of DMABN. PMID:18331006

  17. Comparison of stabilization by Vitamin E and 2,6-di-tert-butylphenols during polyethylene radio-thermal-oxidation

    NASA Astrophysics Data System (ADS)

    Richaud, Emmanuel

    2014-10-01

    This paper reports a compilation of data for PE+Vitamin E and 2,6-di-tert-butylphenols oxidation in radio-thermal ageing. Data unambiguously show that Vitamin E reacts with Prad and POOrad whereas 2,6-di-tert-butyl phenols only react with POOrad . Kinetic parameters of the stabilization reactions for both kinds of antioxidants were tentatively extracted from phenol depletion curves, and discussed regarding the structure of the stabilizer. They were also used for completing an existing kinetic model used for predicting the stabilization by antioxidants. This one permits to compare the efficiency of stabilizer with dose rate or sample thickness.

  18. A c-di-GMP Effector System Controls Cell Adhesion by Inside-Out Signaling and Surface Protein Cleavage

    PubMed Central

    Newell, Peter D.; Boyd, Chelsea D.; Sondermann, Holger; O'Toole, George A.

    2011-01-01

    In Pseudomonas fluorescens Pf0-1 the availability of inorganic phosphate (Pi) is an environmental signal that controls biofilm formation through a cyclic dimeric GMP (c-di-GMP) signaling pathway. In low Pi conditions, a c-di-GMP phosphodiesterase (PDE) RapA is expressed, depleting cellular c-di-GMP and causing the loss of a critical outer-membrane adhesin LapA from the cell surface. This response involves an inner membrane protein LapD, which binds c-di-GMP in the cytoplasm and exerts a periplasmic output promoting LapA maintenance on the cell surface. Here we report how LapD differentially controls maintenance and release of LapA: c-di-GMP binding to LapD promotes interaction with and inhibition of the periplasmic protease LapG, which targets the N-terminus of LapA. We identify conserved amino acids in LapA required for cleavage by LapG. Mutating these residues in chromosomal lapA inhibits LapG activity in vivo, leading to retention of the adhesin on the cell surface. Mutations with defined effects on LapD's ability to control LapA localization in vivo show concomitant effects on c-di-GMP-dependent LapG inhibition in vitro. To establish the physiological importance of the LapD-LapG effector system, we track cell attachment and LapA protein localization during Pi starvation. Under this condition, the LapA adhesin is released from the surface of cells and biofilms detach from the substratum. This response requires c-di-GMP depletion by RapA, signaling through LapD, and proteolytic cleavage of LapA by LapG. These data, in combination with the companion study by Navarro et al. presenting a structural analysis of LapD's signaling mechanism, give a detailed description of a complete c-di-GMP control circuitfrom environmental signal to molecular output. They describe a novel paradigm in bacterial signal transduction: regulation of a periplasmic enzyme by an inner membrane signaling protein that binds a cytoplasmic second messenger. PMID:21304920

  19. Microbiota and metabolome of un-started and started Greek-type fermentation of Bella di Cerignola table olives.

    PubMed

    De Angelis, Maria; Campanella, Daniela; Cosmai, Lucrezia; Summo, Carmine; Rizzello, Carlo Giuseppe; Caponio, Francesco

    2015-12-01

    This study aimed to utilize an "omics" approach to evaluate the ability of selected lactobacilli and yeasts to improve the fermentation process of Bella di Cerignola table olives. Four types of fermentations were performed at the pilot-plant scale: un-started fermented olives used as a control (Ctrl); olives started with a commercial Lactobacillus plantarum strain (S); commercial L. plantarum strain and autochthonous yeast Wickeramomyces anomalus DiSSPA73 (SY); and L. plantarum, W. anomalus DiSSPA73, autochthonous L. plantarum DiSSPA1A7 and Lactobacillus pentosus DiSSPA7 (SYL). Compared to Ctrl, S, SY, SYL showed a higher acidification (P < 0.05) of the brine, which reached a pH value of 4.49 after one day of fermentation. The microbiota of unfermented olives and brine after one day of fermentation was primarily composed of Enterobacteria that belonged to Hafnia alvei and Methylobacterium. However, L. plantarum and L. pentosus dominated the total and metabolically active microbiota of the Ctrl brines and olives at the end of the fermentation. The use of lactobacilli and W. anomalus DiSSPA73 as a starter culture markedly affected the microbiota of the brines after one day of fermentation. The number of species (OTU) and the results of an alpha diversity analysis indicated that the microbial diversity of the brines was markedly simplified by the S, SY and, in particular, SYL fermentations. According to the lowest biodiversity, S, SY and SYL samples showed the lowest abundance of Proteobacteria, including Enterobacteriacea, Lactococcus lactis, Propionibacterium acidipropionici and Clostridium. The lactobacilli and W. anomalus DiSSPA73 used in this study markedly affected the amounts of free amino acids, phenolic and volatile organic compounds. Both a texture profile analysis and a sensory evaluation showed the highest appreciation for all of the started table olives. As shown through microbiological, biochemical, and sensory analyses, an accelerated fermentation of Bella di Cerignola table olives was achieved using the selected lactobacilli and yeast strains. PMID:26338113

  20. Crystal structure of racemic cis-2-amino-1,2-di­phenyl­ethanol (ADE)

    PubMed Central

    Fujii, Isao

    2015-01-01

    In the title racemic compound, C14H15NO, the hy­droxy and amino groups form a bent tweezer-like motif towards the phenyl groups. In the crystal, enanti­omers aggregate with each other and are linked by O—H⋯N hydrogen bonds, forming chiral 21-helical columnar structures from C(5) chains along the b-axis direction. Left- and right-handed 21 helices are formed from (1S,2R)-2-amino-1,2-di­phenyl­ethanol and (1R,2S)-2-amino-1,2-di­phenyl­ethanol, respectively. PMID:26870424

  1. Binding thermodynamics of paromomycin, neomycin, neomycin-dinucleotide and -diPNA conjugates to bacterial and human rRNA.

    PubMed

    Alguacil, Javier; Robles, Jordi; Ràfols, Clara; Bosch, Elisabeth

    2016-04-01

    Isothermal titration calorimetry (ITC) is a powerful technique able to evaluate the energetics of target-drug binding within the context of drug discovery. In this work, the interactions of RNAs reproducing bacterial and human ribosomal A-site, with two well-known antibiotic aminoglycosides, Paromomycin and Neomycin, as well as several Neomycin-dinucleotide and -diPNA conjugates, have been evaluated by ITC and the corresponding thermodynamic quantities determined. The comparison of the thermodynamic data of aminoglycosides and their chemical analogues allowed to select Neomycin-diPNA conjugates as the best candidates for antimicrobial activity. Copyright © 2015 John Wiley & Sons, Ltd. PMID:26530431

  2. Listeria monocytogenes Multidrug Resistance Transporters and Cyclic Di-AMP, Which Contribute to Type I Interferon Induction, Play a Role in Cell Wall Stress

    PubMed Central

    Kaplan Zeevi, Millie; Shafir, Nirit S.; Shaham, Shira; Friedman, Sivan; Sigal, Nadejda; Nir Paz, Ran; Boneca, Ivo G.

    2013-01-01

    The intracellular bacterial pathogen Listeria monocytogenes activates a robust type I interferon response upon infection. This response is partially dependent on the multidrug resistance (MDR) transporter MdrM and relies on cyclic-di-AMP (c-di-AMP) secretion, yet the functions of MdrM and cyclic-di-AMP that lead to this response are unknown. Here we report that it is not MdrM alone but a cohort of MDR transporters that together contribute to type I interferon induction during infection. In a search for a physiological function of these transporters, we revealed that they play a role in cell wall stress responses. A mutant with deletion of four transporter genes (ΔmdrMTAC) was found to be sensitive to sublethal concentrations of vancomycin due to an inability to produce and shed peptidoglycan under this stress. Remarkably, c-di-AMP is involved in this phenotype, as overexpression of the c-di-AMP phosphodiesterase (PdeA) resulted in increased susceptibility of the ΔmdrMTAC mutant to vancomycin, whereas overexpression of the c-di-AMP diadenylate cyclase (DacA) reduced susceptibility to this drug. These observations suggest a physiological association between c-di-AMP and the MDR transporters and support the model that MDR transporters mediate c-di-AMP secretion to regulate peptidoglycan synthesis in response to cell wall stress. PMID:24056102

  3. 40 CFR 721.2275 - N,N,N′,N′-Tetrakis(oxi-ranyl- methyl)-1,3-cyclohexane di-meth-anamine.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false N,N,Nâ²,Nâ²-Tetrakis(oxi-ranyl- methyl)-1,3-cyclohexane di-meth-anamine. 721.2275 Section 721.2275 Protection of Environment ENVIRONMENTAL...-cyclohexane di-meth-anamine. (a) Chemical substances and significant new uses subject to reporting. (1)...

  4. 40 CFR 721.2275 - N,N,N′,N′-Tetrakis(oxi-ranyl- methyl)-1,3-cyclohexane di-meth-anamine.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false N,N,Nâ²,Nâ²-Tetrakis(oxi-ranyl- methyl)-1,3-cyclohexane di-meth-anamine. 721.2275 Section 721.2275 Protection of Environment ENVIRONMENTAL...-cyclohexane di-meth-anamine. (a) Chemical substances and significant new uses subject to reporting. (1)...

  5. 40 CFR 721.2275 - N,N,N′,N′-Tetrakis(oxi-ranyl- methyl)-1,3-cyclohexane di-meth-anamine.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false N,N,Nâ²,Nâ²-Tetrakis(oxi-ranyl- methyl)-1,3-cyclohexane di-meth-anamine. 721.2275 Section 721.2275 Protection of Environment ENVIRONMENTAL...-cyclohexane di-meth-anamine. (a) Chemical substances and significant new uses subject to reporting. (1)...

  6. 40 CFR 721.2275 - N,N,N′,N′-Tetrakis(oxi-ranyl- methyl)-1,3-cyclohexane di-meth-anamine.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false N,N,Nâ²,Nâ²-Tetrakis(oxi-ranyl- methyl)-1,3-cyclohexane di-meth-anamine. 721.2275 Section 721.2275 Protection of Environment ENVIRONMENTAL...-cyclohexane di-meth-anamine. (a) Chemical substances and significant new uses subject to reporting. (1)...

  7. 40 CFR 721.2275 - N,N,N′,N′-Tetrakis(oxi-ranyl- methyl)-1,3-cyclohexane di-meth-anamine.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false N,N,Nâ²,Nâ²-Tetrakis(oxi-ranyl- methyl)-1,3-cyclohexane di-meth-anamine. 721.2275 Section 721.2275 Protection of Environment ENVIRONMENTAL...-cyclohexane di-meth-anamine. (a) Chemical substances and significant new uses subject to reporting. (1)...

  8. 40 CFR 721.9516 - Siloxanes and silicones, 3-[(2-aminoethyl) amino]propyl Me, di-Me, reaction products with...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ..., di-Me, reaction products with polyethylene-polypropylene glycol Bu glycidal ether. 721.9516 Section... CONTROL ACT SIGNIFICANT NEW USES OF CHEMICAL SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.9516 Siloxanes and silicones, 3- propyl Me, di-Me, reaction products with...

  9. 40 CFR 721.9516 - Siloxanes and silicones, 3-[(2-aminoethyl) amino]propyl Me, di-Me, reaction products with...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ..., di-Me, reaction products with polyethylene-polypropylene glycol Bu glycidal ether. 721.9516 Section... CONTROL ACT SIGNIFICANT NEW USES OF CHEMICAL SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.9516 Siloxanes and silicones, 3- propyl Me, di-Me, reaction products with...

  10. 40 CFR 721.9516 - Siloxanes and silicones, 3-[(2-aminoethyl) amino]propyl Me, di-Me, reaction products with...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ..., di-Me, reaction products with polyethylene-polypropylene glycol Bu glycidal ether. 721.9516 Section... CONTROL ACT SIGNIFICANT NEW USES OF CHEMICAL SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.9516 Siloxanes and silicones, 3- propyl Me, di-Me, reaction products with...

  11. 40 CFR 721.6900 - Polymer of bisphenol A di-glyc-i-dal ether, substituted al-kenes, and but-a-diene.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 31 2014-07-01 2014-07-01 false Polymer of bisphenol A di-glyc-i-dal... SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.6900 Polymer of bisphenol A di-glyc-i... subject to reporting. (1) The chemical substances identified generically as polymer of bisphenol...

  12. 40 CFR 721.6900 - Polymer of bisphenol A di-glyc-i-dal ether, substituted al-kenes, and but-a-diene.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Polymer of bisphenol A di-glyc-i-dal... SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.6900 Polymer of bisphenol A di-glyc-i... subject to reporting. (1) The chemical substances identified generically as polymer of bisphenol...

  13. 40 CFR 721.6900 - Polymer of bisphenol A di-glyc-i-dal ether, substituted al-kenes, and but-a-diene.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Polymer of bisphenol A di-glyc-i-dal... SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.6900 Polymer of bisphenol A di-glyc-i... subject to reporting. (1) The chemical substances identified generically as polymer of bisphenol...

  14. 40 CFR 721.6900 - Polymer of bisphenol A di-glyc-i-dal ether, substituted al-kenes, and but-a-diene.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Polymer of bisphenol A di-glyc-i-dal... SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.6900 Polymer of bisphenol A di-glyc-i... subject to reporting. (1) The chemical substances identified generically as polymer of bisphenol...

  15. 40 CFR 721.6900 - Polymer of bisphenol A di-glyc-i-dal ether, substituted al-kenes, and but-a-diene.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false Polymer of bisphenol A di-glyc-i-dal... SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.6900 Polymer of bisphenol A di-glyc-i... subject to reporting. (1) The chemical substances identified generically as polymer of bisphenol...

  16. Deletion of the cyclic di-AMP phosphodiesterase gene (cnpB) in Mycobacterium tuberculosis leads to reduced virulence in a mouse model of infection

    PubMed Central

    Yang, Jun; Bai, Yinlan; Zhang, Yang; Gabrielle, Vincent D.; Jin, Lei; Bai, Guangchun

    2014-01-01

    Summary Tuberculosis (TB) remains a major cause of morbidity and mortality worldwide. The pathogenesis by the causative agent, Mycobacterium tuberculosis, is still not fully understood. We have previously reported that M. tuberculosis Rv3586 (disA) encodes a diadenylate cyclase, which converts ATP to cyclic di-AMP (c-di-AMP). In this study, we demonstrated that a protein encoded by Rv2837c (cnpB) possesses c-di-AMP phosphodiesterase activity and cleaves c-di-AMP exclusively to AMP. Our results showed that in M. tuberculosis, deletion of disA abolished bacterial c-di-AMP production, whereas deletion of cnpB significantly enhanced the bacterial c-di-AMP accumulation and secretion. The c-di-AMP levels in both mutants could be corrected by expressing the respective gene. We also found that macrophages infected with ΔcnpB secreted much higher levels of IFN-β than those infected with the wildtype (WT) or the complemented mutant. Interestingly, mice infected with M. tuberculosis ΔcnpB displayed significantly reduced inflammation, less bacterial burden in the lungs and spleens, and extended survival compared to those infected with the WT or the complemented mutant. These results indicate that deletion of cnpB results in attenuated virulence, which is correlated with elevated c-di-AMP levels. PMID:24806618

  17. 40 CFR 721.9516 - Siloxanes and silicones, 3-[(2-aminoethyl) amino]propyl Me, di-Me, reaction products with...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ..., di-Me, reaction products with polyethylene-polypropylene glycol Bu glycidal ether. 721.9516 Section... Substances § 721.9516 Siloxanes and silicones, 3- propyl Me, di-Me, reaction products with polyethylene..., reaction products with polyethylene-polypropylene glycol Bu glycidyl ether (PMN P-97-740; CAS No....

  18. 40 CFR 721.9516 - Siloxanes and silicones, 3-[(2-aminoethyl) amino]propyl Me, di-Me, reaction products with...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ..., di-Me, reaction products with polyethylene-polypropylene glycol Bu glycidal ether. 721.9516 Section... Substances § 721.9516 Siloxanes and silicones, 3- propyl Me, di-Me, reaction products with polyethylene..., reaction products with polyethylene-polypropylene glycol Bu glycidyl ether (PMN P-97-740; CAS No....

  19. The Screening Accuracy of the Parent and Teacher-Reported Social Responsiveness Scale (SRS): Comparison with the 3Di and ADOS

    ERIC Educational Resources Information Center

    Duvekot, Jorieke; van der Ende, Jan; Verhulst, Frank C.; Greaves-Lord, Kirstin

    2015-01-01

    The screening accuracy of the parent and teacher-reported Social Responsiveness Scale (SRS) was compared with an autism spectrum disorder (ASD) classification according to (1) the Developmental, Dimensional, and Diagnostic Interview (3Di), (2) the Autism Diagnostic Observation Schedule (ADOS), (3) both the 3Di and ADOS, in 186 children referred to…

  20. Structural and Biochemical Insight into the Mechanism of Rv2837c from Mycobacterium tuberculosis as a c-di-NMP Phosphodiesterase.

    PubMed

    He, Qing; Wang, Feng; Liu, Shiheng; Zhu, Deyu; Cong, Hengjiang; Gao, Fei; Li, Bingqing; Wang, Hongwei; Lin, Zong; Liao, Jun; Gu, Lichuan

    2016-02-12

    The intracellular infections of Mycobacterium tuberculosis, which is the causative agent of tuberculosis, are regulated by many cyclic dinucleotide signaling. Rv2837c from M. tuberculosis is a soluble, stand-alone DHH-DHHA1 domain phosphodiesterase that down-regulates c-di-AMP through catalytic degradation and plays an important role in M. tuberculosis infections. Here, we report the crystal structure of Rv2837c (2.0 Å), and its complex with hydrolysis intermediate 5'-pApA (2.35 Å). Our structures indicate that both DHH and DHHA1 domains are essential for c-di-AMP degradation. Further structural analysis shows that Rv2837c does not distinguish adenine from guanine, which explains why Rv2837c hydrolyzes all linear dinucleotides with almost the same efficiency. We observed that Rv2837c degraded other c-di-NMPs at a lower rate than it did on c-di-AMP. Nevertheless, our data also showed that Rv2837c significantly decreases concentrations of both c-di-AMP and c-di-GMP in vivo. Our results suggest that beside its major role in c-di-AMP degradation Rv2837c could also regulate c-di-GMP signaling pathways in bacterial cell. PMID:26668313

  1. Crystal structure of di­aqua­bis­(2,6-di­methyl­pyrazine-κN)bis­(thio­cyanato-κN)cobalt(II) 2,5-di­methyl­pyrazine tris­olvate

    PubMed Central

    Suckert, Stefan; Wöhlert, Susanne; Jess, Inke; Näther, Christian

    2015-01-01

    In the crystal structure of the title compound, [Co(NCS)2(C6H8N2)2(H2O)2]·3C6H8N2, the CoII cation is coordinated by two terminally N-bound thio­cyanate anions, two water mol­ecules and two 2,6-di­methyl­pyrazine ligands, forming a discrete complex with a slightly distorted octa­hedral N4O2 coordination environment. The asymmetric unit contains one CoII cation and three halves of 2,5-di­methyl­pyrazine solvate mol­ecules, all entities being completed by inversion symmetry, as well as one thio­cyanate anion, an aqua ligand and a 2,6-di­methyl­pyrazine ligand, all in general positions. In the crystal, discrete complexes are arranged in a way that cavities are formed where the noncoordinating 2,5-di­methyl­pyrazine mol­ecules are located. The coordination of the latter to the metal is prevented due to the bulky methyl groups in vicinal positions to the N atoms, leading to a preferential coordination through the 2,6-di­methyl­pyrazine ligands. The complex mol­ecules are linked by O—H⋯N hydrogen bonds between the water H atoms and the N atoms of 2,5-di­methyl­pyrazine solvent mol­ecules, leading to a layered structure extending parallel to (100). PMID:26870459

  2. Intracellular Concentrations of Borrelia burgdorferi Cyclic Di-AMP Are Not Changed by Altered Expression of the CdaA Synthase.

    PubMed

    Savage, Christina R; Arnold, William K; Gjevre-Nail, Alexandra; Koestler, Benjamin J; Bruger, Eric L; Barker, Jeffrey R; Waters, Christopher M; Stevenson, Brian

    2015-01-01

    The second messenger nucleotide cyclic diadenylate monophosphate (c-di-AMP) has been identified in several species of Gram positive bacteria and Chlamydia trachomatis. This molecule has been associated with bacterial cell division, cell wall biosynthesis and phosphate metabolism, and with induction of type I interferon responses by host cells. We demonstrate that B. burgdorferi produces a c-di-AMP synthase, which we designated CdaA. Both CdaA and c-di-AMP levels are very low in cultured B. burgdorferi, and no conditions were identified under which cdaA mRNA was differentially expressed. A mutant B. burgdorferi was produced that expresses high levels of CdaA, yet steady state borrelial c-di-AMP levels did not change, apparently due to degradation by the native DhhP phosphodiesterase. The function(s) of c-di-AMP in the Lyme disease spirochete remains enigmatic. PMID:25906393

  3. Intracellular Concentrations of Borrelia burgdorferi Cyclic Di-AMP Are Not Changed by Altered Expression of the CdaA Synthase

    PubMed Central

    Savage, Christina R.; Arnold, William K.; Gjevre-Nail, Alexandra; Koestler, Benjamin J.; Bruger, Eric L.; Barker, Jeffrey R.; Waters, Christopher M.; Stevenson, Brian

    2015-01-01

    The second messenger nucleotide cyclic diadenylate monophosphate (c-di-AMP) has been identified in several species of Gram positive bacteria and Chlamydia trachomatis. This molecule has been associated with bacterial cell division, cell wall biosynthesis and phosphate metabolism, and with induction of type I interferon responses by host cells. We demonstrate that B. burgdorferi produces a c-di-AMP synthase, which we designated CdaA. Both CdaA and c-di-AMP levels are very low in cultured B. burgdorferi, and no conditions were identified under which cdaA mRNA was differentially expressed. A mutant B. burgdorferi was produced that expresses high levels of CdaA, yet steady state borrelial c-di-AMP levels did not change, apparently due to degradation by the native DhhP phosphodiesterase. The function(s) of c-di-AMP in the Lyme disease spirochete remains enigmatic. PMID:25906393

  4. Penta­aqua­(di­methyl­formamide)­cobalt(II) sulfate di­methyl­formamide monosolvate

    PubMed Central

    Taş, Murat; Çamur, Seval; Topal, Sevim

    2013-01-01

    The title compound, [Co(C3H7NO)(H2O)5]SO4·C3H7NO, contains five aqua ligands, a CoII atom, a sulfate ion and both a coordinating and a non-coordinating di­methyl­formamide (DMF) mol­ecule. The DMF solvent mol­ecule lies between the complex units, which are located along the b axis. The sulfate ion is for charge balance. The CoII atom has distorted octa­hedral coordination geometry, being ligated by five aqua ligands and the O atom of the DMF ligand. O—H⋯O hydrogen bonds between the aqua ligands and the sulfate anion and non-coordinating DMF molecule lead to the formation of a three-dimensional network. Since all constituents lie on a mirror plane, the H atoms of all methyl groups and of one of the aqua ligands are equally disordered over two positions. PMID:24046556

  5. 1-(2,3-Di-hydroxy-prop-yl)-4-{2-[4-(di-methyl-amino)-phen-yl]vin-yl}pyridinium chloride.

    PubMed

    Gainsford, Graeme J; Bhuiyan, M Delower H; Kay, Andrew J

    2014-01-01

    The title compound, C18H23N2O2 (+)·Cl(-), crystallizes with two independent cations and anions per cell. Each cation has twofold rotational disorder about the linking vinyl groups but with unequal occupancies [0.963 (5):0.037 (5) and 0.860 (8):0.140 (8)]. The two independent cations are close to being related by an inversion centre but the data does not support the expected centrosymmetric space-group assignment. The conclusion is that the differing rotational disorder has lead to an overall non-centrosymmetric lattice. In the crystal, the mol-ecules pack in layers parallel to (133) and (-13-3), chain-linked with motif C (1) 2(7) by the di-hydroxy-propyl O-H⋯Cl⋯H-O hydrogen bonds. Other lattice binding is provided by O-H⋯Cl, C-H⋯Cl and C-H⋯N inter-actions. PMID:24527014

  6. Crystal structure of 2-amino-1,3-di-bromo-6-oxo-5,6-di-hydro-pyrido[1,2-a]quinoxalin-11-ium bromide monohydrate.

    PubMed

    Faizi, Md Serajul Haque; Parashchenko, Yuliia

    2015-11-01

    In the title hydrated salt, C12H8Br2N3O(+)·Br(-)·H2O, which was synthesized by the reaction of the pyridine derivative Schiff base N (1),N (4)-bis-(pyridine-2-yl-methyl-ene)benzene-1,4-di-amine with bromine, the asymmetric unit contains a 2-amino-1,3-di-bromo-6-oxo-5,6-di-hydro-pyrido[1,2-a]quinoxalin-11-ium cation, with a protonated pyridine moiety, a bromide anion and a water mol-ecule of solvation. The cation is non-planar with the di-bromo-substituted benzene ring, forming dihedral angles of 24.3 (4) and 11.5 (4)° with the fused pyridine and pyrazine ring moieties, respectively. In the crystal, the cations are linked through a centrosymmetric hydrogen-bonded cyclic R 4 (2)(8) Br2(H2O)2 unit by N-H⋯Br, N-H⋯O and O-H⋯Br hydrogen bonds, forming one-dimensional ribbons extending along b, with the planes of the cations lying parallel to (100). PMID:26594504

  7. Crystal structure of 2-amino-1,3-dibromo-6-oxo-5,6-dihydropyrido[1,2-a]quinoxalin-11-ium bromide monohydrate

    PubMed Central

    Faizi, Md. Serajul Haque; Parashchenko, Yuliia

    2015-01-01

    In the title hydrated salt, C12H8Br2N3O+Br?H2O, which was synthesized by the reaction of the pyridine derivative Schiff base N 1,N 4-bis(pyridine-2-ylmethylene)benzene-1,4-diamine with bromine, the asymmetric unit contains a 2-amino-1,3-dibromo-6-oxo-5,6-dihydropyrido[1,2-a]quinoxalin-11-ium cation, with a protonated pyridine moiety, a bromide anion and a water molecule of solvation. The cation is non-planar with the dibromo-substituted benzene ring, forming dihedral angles of 24.3?(4) and 11.5?(4) with the fused pyridine and pyrazine ring moieties, respectively. In the crystal, the cations are linked through a centrosymmetric hydrogen-bonded cyclic R 4 2(8) Br2(H2O)2 unit by NH?Br, NH?O and OH?Br hydrogen bonds, forming one-dimensional ribbons extending along b, with the planes of the cations lying parallel to (100). PMID:26594504

  8. Poly[[nona-aqua-bis-(μ-5-hy-droxy-benzene-1,3-di-carboxyl-ato)(5-hy-droxy-benzene-1,3-di-carboxyl-ato)dicerium(III)] hexa-hydrate].

    PubMed

    Fan, Xiao; Daiguebonne, Carole; Guillou, Olivier; Camara, Magatte

    2014-05-01

    In the title coordination polymer, {[Ce2(C8H4O5)3(H2O)9]·6H2O} n , the asymmetric unit is formed by two Ce(III) atoms, three 5-hy-droxy-benzene-1,3-di-carboxyl-ate ligands, nine coordinating water mol-ecules and six water mol-ecules of crystallization. The two Ce(III) atoms are bridged by 5-hy-droxy-benzene-1,3-di-carboxyl-ate ligands acting in a bis-bidentate coordination mode, generating infinite chains along [101]. Both independent metal atoms are nine-coordinated, one by four O atoms from the carboxyl-ate groups of two bridging 5-hy-droxy-benzene-1,3-di-carboxyl-ate ligands and five O atoms from water mol-ecules, generating a tricapped trigonal-prismatic geometry. The coordination around the second Ce(III) atom is similar, except that one of the water mol-ecules is replaced by an O atom from an additional 5-hy-droxy-benzene-1,3-di-carboxyl-ate ligand acting in a monodentate coordination mode and forming a capped square-anti-prismatic geometry. PMID:24860313

  9. Molecular basis for the recognition of cyclic-di-AMP by PstA, a PII-like signal transduction protein

    PubMed Central

    Choi, Philip H; Sureka, Kamakshi; Woodward, Joshua J; Tong, Liang

    2015-01-01

    Cyclic-di-AMP (c-di-AMP) is a broadly conserved bacterial second messenger that is of importance in bacterial physiology. The molecular receptors mediating the cellular responses to the c-di-AMP signal are just beginning to be discovered. PstA is a previously uncharacterized PII-like protein which has been identified as a c-di-AMP receptor. PstA is widely distributed and conserved among Gram-positive bacteria in the phylum Firmicutes. Here, we report the biochemical, structural, and functional characterization of PstA from Listeria monocytogenes. We have determined the crystal structures of PstA in the c-di-AMP-bound and apo forms at 1.6 and 2.9 Å resolution, respectively, which provide the molecular basis for its specific recognition of c-di-AMP. PstA forms a homotrimer structure that has overall similarity to the PII protein family which binds ATP. However, PstA is markedly different from PII proteins in the loop regions, and these structural differences mediate the specific recognition of their respective nucleotide ligand. The residues composing the c-di-AMP binding pocket are conserved, suggesting that c-di-AMP recognition by PstA is of functional importance. Disruption of pstA in L. monocytogenes affected c-di-AMP-mediated alterations in bacterial growth and lysis. Overall, we have defined the PstA family as a conserved and specific c-di-AMP receptor in bacteria. PMID:25693966

  10. Di-Hadron Angular Correlation Dependence on Leading Hadron Identity in Relativistic Heavy Ion Collisions

    NASA Astrophysics Data System (ADS)

    Kauder, Kolja

    A unique state of matter is created in ultra-relativistic heavy ion collisions at the Relativistic Heavy Ion Collider (RHIC) and the Large Hadron Collider (LHC), the Quark Gluon Plasma (QGP). It displays the properties of a near-perfect liquid of quarks and gluons (partons) interacting collectively via the strong force. Properties of this medium can be explored using high-energy probes created in the form of back-to-back pairs (jets) in hard scatterings. A distinct feature of the QGP is jet quenching, which describes the large energy loss of such probes observed in measurements of hadron distributions in head-on heavy ion collisions. A more differential measurement of jet quenching is achieved using di-hadron correlations, where relative angular distributions are studied with respect to a leading (high energy) "trigger" hadron. Two striking features found in di-hadron correlations are the emergence of a long-range plateau on the near-side (at small relative azimuth), the so-called "ridge", and a broadening and deformation of the away-side, back to back with the trigger. Using 200 GeV central gold-gold and minimum bias deuteron-gold collision data collected by the STAR detector at RHIC, a systematic study of the dependence of di-hadron correlation structures on the identity of the trigger particle is carried out in this work by statistically separating pion from non-pion (i.e. proton and kaon) triggers, offering new insights into the hadronization mechanisms in the QGP. The jet-like yield at small relative angles is found enhanced for leading pions in Au+Au data with respect to the d+Au reference, while leading non-pions (protons and kaons) do not elicit such an enhancement. These findings are discussed within the context of quark recombination. At large angles, the correlated yield is significantly higher for leading non-pions than pions. Parameters extracted from two-dimensional model fits are used to test consistency with the constituent quark scaling assumptions in an azimuthal harmonics model, as well as the applicability of a mini-jet modification model.

  11. The Eclipsing Binary Di Herculis: One Mystery Solved, But Another Takes Its Place

    NASA Astrophysics Data System (ADS)

    Zimmerman, Nicole; Guinan, E.; Maloney, F.

    2010-01-01

    The 8th-mag eclipsing binary DI Herculis has perplexed scientists for the past few decades due to its anomalously slow apsidal motion rate. DI Her consists of two main-sequence stars (B5V, B6V), with P(orb) = 10.55 days, and eccentricity(e= 0.489). Since the apsidal motion is dominated by General Relativity, the system is one of the few tests available for verifying the theory. Combining the expected classical (1.93/100 yr) and relativistic (2.34/100 yr) effects, the predicted apsidal motion rate is 4.27/100 yr. Our recent determination of the apsidal motion yields 1.33+/-0.25 /100 yr, based on eclipse timings from 1936-2008. Recently, Albrecht et al (2009, Nature 461) have apparently solved the apsidal motion anomaly of DI Her, finding that the axes of both stars are significantly inclined from the normal to the orbital plane. This was determined from the radial velocity curves and observing the Rossiter-McLaughlin effect during primary and secondary eclipses. Having significantly misaligned axes of rotation produces a perturbation that greatly reduces the classical apsidal motion effect, thus explaining the observed small apsidal motion rate. Even though this discovery apparently solves the problem, it raises new questions as to how the axes are so tilted. Additionally, tilted axes are expected to contribute to other orbital effects, such as changes in orbital inclination, which have not yet observed from the apparent constancy in eclipse depths over time. We have also searched for evidence of small periodic oscillations in the eclipse timings and found no evidence of a light travel time effect arising from a possible tertiary component. Further, we find evidence that the projected rotation axes of the stars may be precessing, since it appears that the value of V(rot)sini has increased over the past 30 years. This research was supported by NSF/RUI Grants AST05-07536/42.

  12. Di-, tri-, and tetranuclear copper(I) complexes of phenanthroline-linked dicarbene ligands.

    PubMed

    Liu, Bo; Pan, Shanfei; Liu, Bin; Chen, Wanzhi

    2014-10-01

    A family of 2,9-di(3-R-1H-imidazolium-1-yl)-1,10-phenanthroline iodides and hexafluorophosphates (R = allyl, benzyl, mesityl, picolyl) were synthesized from 2,9-diiodophenanthroline and imidazole or N-substituted imidazoles. Simple reactions of these diimidazolium salts with copper powder at room temperature have afforded a series of multinuclear copper(I)-NHC complexes in good yields. The structures vary depending on the N substituents and counterions. [Cu4(L1)2(MeCN)4](PF6)4 (R = allyl) exhibits a zigzag Cu4 chain with two terminal [Cu(NHC)(MeCN)2] and two internal [Cu(phen)(NHC)] moieties. [Cu3(L2)2](PF6)3 (R = benzyl) contains a strictly linear Cu3 framework with two [Cu(NHC)2] units and a [Cu(phen)2] located at the center. Both complexes [Cu3(L4)2](PF6)3 (R = mesityl) and [Cu3(L5)2](PF6)3 (R = picolyl) consist of a triangular Cu3 core in which two copper(I) ions are surrounded by a phen and a NHC group and the third copper(I) is coordinated by two NHC groups. [Cu3(L3)2](PF6)3 derived from 2,9-di(3-benzyl-1H-benzimidazolium-1-yl)-1,10-phenanthroline hexafluorophosphate can undergo transannulation of the benzimidazolylidene ring giving [Cu2(L3')2](PF6)2. The decomposition process might involve solvent-induced rearrangement of the ligand and hydrolysis of carbene moieties. Treatment of 2,9-di(3-mesityl-1H-benzimidazolium-1-yl)-1,10-phenanthroline iodide with copper powder generated dinuclear complex [Cu2(L4)2][Cu2(μ-I)2I2] (R = mesityl) possessing a macrocyclic cation and [Cu2(μ-I)2I2](2-) anion. Tetranuclear complex [Cu4(L5)2(μ-I)2](CuI3) (R = picolyl) has been obtained from its diimidazolium iodide and copper powder. All Cu(I) complexes have been characterized by X-ray single diffraction analysis, elemental analysis, and NMR spectra. Their redox behavior and fluorescent properties have also been studied. PMID:25216090

  13. Impact of Age on the Cerebrovascular Proteomes of Wild-Type and Tg-SwDI Mice

    PubMed Central

    Searcy, James L.; Le Bihan, Thierry; Salvadores, Natalia; McCulloch, James; Horsburgh, Karen

    2014-01-01

    The structural integrity of cerebral vessels is compromised during ageing. Abnormal amyloid (Aβ) deposition in the vasculature can accelerate age-related pathologies. The cerebrovascular response associated with ageing and microvascular Aβ deposition was defined using quantitative label-free shotgun proteomic analysis. Over 650 proteins were quantified in vessel-enriched fractions from the brains of 3 and 9 month-old wild-type (WT) and Tg-SwDI mice. Sixty-five proteins were significantly increased in older WT animals and included several basement membrane proteins (nidogen-1, basement membrane-specific heparan sulfate proteoglycan core protein, laminin subunit gamma-1 precursor and collagen alpha-2(IV) chain preproprotein). Twenty-four proteins were increased and twenty-one decreased in older Tg-SwDI mice. Of these, increases in Apolipoprotein E (APOE) and high temperature requirement serine protease-1 (HTRA1) and decreases in spliceosome and RNA-binding proteins were the most prominent. Only six shared proteins were altered in both 9-month old WT and Tg-SwDI animals. The age-related proteomic response in the cerebrovasculature was distinctly different in the presence of microvascular Aβ deposition. Proteins found differentially expressed within the WT and Tg-SwDI animals give greater insight to the mechanisms behind age-related cerebrovascular dysfunction and pathologies and may provide novel therapeutic targets. PMID:24587158

  14. [Analysis on medication principles for cough based on experience of Xu Di-hua, descendant of Meng He Medical School].

    PubMed

    Xu, Xiao-jing; Xu, Li-min; Shen, Chun-feng; Wang, Cai-hua; Shen, Chun-ti

    2015-11-01

    Based on the software of traditional Chinese medicine inheritance support system (TCMISS), this article aims to analyze the experience and composition rules for cough from the descendant of Meng He Medical School, Xu Di-hua. The cough cases treated by Xu Di-hua were collected, and recorded into TCMISS (V2.0). Data mining methods such as Apriori algorithm and complex system entropy cluster were used to analyze the medication principles of Xu Di-hua for cough from pathogenesis and therapeutie aspects, and dig out the frequency of the herbs in prescription, core medicine and new combinations. The experience of curing cough from Professor Xu Di-hua were well found in the research. He is good at choosing prescriptions accurately, and pays attention to simultaneous use of cold and moisture drugs with combination of tonification and purgation. He is skilled in adding or reducing materia medica flexibly, as well as regulating lung to relieve cough and eliminating phlegm by clearing heat. PMID:27071274

  15. 40 CFR 721.7260 - Polymer of poly-ethylene-polyamine and alkanediol di-gly-cidyl ether.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... AGENCY (CONTINUED) TOXIC SUBSTANCES CONTROL ACT SIGNIFICANT NEW USES OF CHEMICAL SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.7260 Polymer of poly-ethylene-polyamine and alkanediol di-gly-cidyl ether. (a) Chemical substance and significant new uses subject to reporting. (1)...

  16. 40 CFR 721.7260 - Polymer of poly-ethylene-polyamine and alkanediol di-gly-cidyl ether.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... AGENCY (CONTINUED) TOXIC SUBSTANCES CONTROL ACT SIGNIFICANT NEW USES OF CHEMICAL SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.7260 Polymer of poly-ethylene-polyamine and alkanediol di-gly-cidyl ether. (a) Chemical substance and significant new uses subject to reporting. (1)...

  17. 40 CFR 721.7260 - Polymer of poly-ethylene-polyamine and alkanediol di-gly-cidyl ether.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Polymer of poly-ethylene-polyamine and alkanediol di-gly-cidyl ether. 721.7260 Section 721.7260 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC SUBSTANCES CONTROL ACT SIGNIFICANT NEW USES OF CHEMICAL SUBSTANCES Significant New Uses for Specific...

  18. Differential inhibition of cellular and viral pp60src kinase by P1,P4-di(adenosine-5')tetraphosphate.

    PubMed Central

    Levy, B T; Sorge, L K; Drum, C C; Maness, P F

    1983-01-01

    We contrasted the protein kinase activities of pp60v-src, the transforming protein of Rous sarcoma virus, and its normal cellular homolog pp60c-src with respect to inhibition by P1,P4-di(adenosine-5')tetraphosphate by using the immune complex protein kinase assay. The concentration of P1,P4-di(adenosine-5')tetraphosphate required for 50% inhibition of pp60v-src kinase (1 microM) was found to be significantly lower than that required for inhibition of pp60c-src kinase (46 microM). Viral and cellular pp60src kinases differed to a lesser extent with respect to inhibition by adenosine-5'-tetraphosphate, di(guanosine-5')tetraphosphate, and ADP. No significant differences were found in the ATP Km values of pp60v-src (0.108 +/- 0.048 microM) and pp60c-src kinases (0.056 +/- 0.012 microM). These results demonstrate that the protein kinase activities of viral and cellular pp60src are functionally distinguishable, particularly on the basis of enhanced sensitivity of the viral enzyme to inhibition by P1,P4-di(adenosine-5')tetraphosphate. These functional differences are likely to be due to differences in the conformation of the active site and may be important for determining transformation potential. PMID:6196614

  19. ALTERATIONS IN COMPOSITION OF FIELD- AND LABORATORY-DEVELOPED ESTUARINE BENTHIC COMMUNITIES EXPOSED TO DI-N-BUTYL PHTHALATE

    EPA Science Inventory

    Macrobenthic animal communities, developed in sand-filled aquaria in the laboratory and in the field, were exposed to three concentrations of the plasticizer, di-n-butyl phthalate (DBP), and effects on community structure assessed. Laboratory communities were colonized by plankto...

  20. Streptococcus pyogenes c-di-AMP Phosphodiesterase, GdpP, Influences SpeB Processing and Virulence

    PubMed Central

    Cho, Kyu Hong; Kang, Song Ok

    2013-01-01

    Small cyclic nucleotide derivatives are employed as second messengers by both prokaryotes and eukaryotes to regulate diverse cellular processes responding to various signals. In bacteria, c-di-AMP has been discovered most recently, and some Gram-positive pathogens including S. pyogenes use this cyclic nucleotide derivative as a second messenger instead of c-di-GMP, a well-studied important bacterial second messenger. GdpP, c-di-AMP phosphodiesterase, is responsible for degrading c-di-AMP inside cells, and the cellular role of GdpP in S. pyogenes has not been examined yet. To test the cellular role of GdpP, we created a strain with a nonpolar inframe deletion of the gdpP gene, and examined the properties of the strain including virulence. From this study, we demonstrated that GdpP influences the biogenesis of SpeB, the major secreted cysteine protease, at a post-translational level, susceptibility to the beta lactam antibiotic ampicillin, and is necessary for full virulence in a murine subcutaneous infection model. PMID:23869242

  1. The hmsT 3' untranslated region mediates c-di-GMP metabolism and biofilm formation in Yersinia pestis.

    PubMed

    Zhu, Hui; Mao, Xu-Jian; Guo, Xiao-Peng; Sun, Yi-Cheng

    2016-03-01

    Yersinia pestis, the cause of plague, forms a biofilm in the proventriculus of its flea vector to enhance transmission. Biofilm formation in Y. pestis is regulated by the intracellular levels of cyclic diguanylate (c-di-GMP). In this study, we investigated the role of the 3' untranslated region (3'UTR) in hmsT mRNA, a transcript that encodes a diguanylate cyclase that stimulates biofilm formation in Y. pestis by synthesizing the second messenger c-di-GMP. Deletion of the 3'UTR increased the half-life of hmsT mRNA, thereby upregulating c-di-GMP levels and biofilm formation. Our findings indicate that multiple regulatory sequences might be present in the hmsT 3'UTR that function together to mediate mRNA turnover. We also found that polynucleotide phosphorylase is partially responsible for hmsT 3'UTR-mediated mRNA decay. In addition, the hmsT 3'UTR strongly repressed gene expression at 37°C and 26°C, but affected gene expression only slightly at 21°C. Our findings suggest that the 3'UTR might be involved in precise and rapid regulation of hmsT expression, allowing Y. pestis to fine-tune c-di-GMP synthesis and consequently regulate biofilm production to adapt to the changing host environment. PMID:26711808

  2. Di-electron spectrum at mid-rapidity in p+p collisions at s=200 GeV

    NASA Astrophysics Data System (ADS)

    Adamczyk, L.; Agakishiev, G.; Aggarwal, M. M.; Ahammed, Z.; Alakhverdyants, A. V.; Alekseev, I.; Alford, J.; Anderson, B. D.; Anson, C. D.; Arkhipkin, D.; Aschenauer, E.; Averichev, G. S.; Balewski, J.; Banerjee, A.; Barnovska, Z.; Beavis, D. R.; Bellwied, R.; Betancourt, M. J.; Betts, R. R.; Bhasin, A.; Bhati, A. K.; Bichsel, H.; Bielcik, J.; Bielcikova, J.; Bland, L. C.; Bordyuzhin, I. G.; Borowski, W.; Bouchet, J.; Brandin, A. V.; Brovko, S. G.; Bruna, E.; Bueltmann, S.; Bunzarov, I.; Burton, T. P.; Butterworth, J.; Cai, X. Z.; Caines, H.; Calderón de la Barca Sánchez, M.; Cebra, D.; Cendejas, R.; Cervantes, M. C.; Chaloupka, P.; Chang, Z.; Chattopadhyay, S.; Chen, H. F.; Chen, J. H.; Chen, J. Y.; Chen, L.; Cheng, J.; Cherney, M.; Chikanian, A.; Christie, W.; Chung, P.; Chwastowski, J.; Codrington, M. J. M.; Corliss, R.; Cramer, J. G.; Crawford, H. J.; Cui, X.; Davila Leyva, A.; De Silva, L. C.; Debbe, R. R.; Dedovich, T. G.; Deng, J.; Derradi de Souza, R.; Dhamija, S.; Didenko, L.; Ding, F.; Dion, A.; Djawotho, P.; Dong, X.; Drachenberg, J. L.; Draper, J. E.; Du, C. M.; Dunkelberger, L. E.; Dunlop, J. C.; Efimov, L. G.; Elnimr, M.; Engelage, J.; Eppley, G.; Eun, L.; Evdokimov, O.; Fatemi, R.; Fazio, S.; Fedorisin, J.; Fersch, R. G.; Filip, P.; Finch, E.; Fisyak, Y.; Gagliardi, C. A.; Gangadharan, D. R.; Geurts, F.; Gibson, A.; Gliske, S.; Gorbunov, Y. N.; Grebenyuk, O. G.; Grosnick, D.; Gupta, S.; Guryn, W.; Haag, B.; Hajkova, O.; Hamed, A.; Han, L.-X.; Harris, J. W.; Hays-Wehle, J. P.; Heppelmann, S.; Hirsch, A.; Hoffmann, G. W.; Hofman, D. J.; Horvat, S.; Huang, B.; Huang, H. Z.; Huck, P.; Humanic, T. J.; Huo, L.; Igo, G.; Jacobs, W. W.; Jena, C.; Joseph, J.; Judd, E. G.; Kabana, S.; Kang, K.; Kapitan, J.; Kauder, K.; Ke, H. W.; Keane, D.; Kechechyan, A.; Kesich, A.; Kettler, D.; Kikola, D. P.; Kiryluk, J.; Kisiel, A.; Kizka, V.; Klein, S. R.; Koetke, D. D.; Kollegger, T.; Konzer, J.; Koralt, I.; Koroleva, L.; Korsch, W.; Kotchenda, L.; Kravtsov, P.; Krueger, K.; Kumar, L.; Lamont, M. A. C.; Landgraf, J. M.; LaPointe, S.; Lauret, J.; Lebedev, A.; Lednicky, R.; Lee, J. H.; Leight, W.; LeVine, M. J.; Li, C.; Li, L.; Li, W.; Li, X.; Li, X.; Li, Y.; Li, Z. M.; Lima, L. M.; Lisa, M. A.; Liu, F.; Ljubicic, T.; Llope, W. J.; Longacre, R. S.; Lu, Y.; Luo, X.; Luszczak, A.; Ma, G. L.; Ma, Y. G.; Madagodagettige Don, D. M. M. D.; Mahapatra, D. P.; Majka, R.; Mall, O. I.; Margetis, S.; Markert, C.; Masui, H.; Matis, H. S.; McDonald, D.; McShane, T. S.; Mioduszewski, S.; Mitrovski, M. K.; Mohammed, Y.; Mohanty, B.; Mondal, M. M.; Morozov, B.; Munhoz, M. G.; Mustafa, M. K.; Naglis, M.; Nandi, B. K.; Nasim, Md.; Nayak, T. K.; Nogach, L. V.; Novak, J.; Odyniec, G.; Ogawa, A.; Oh, K.; Ohlson, A.; Okorokov, V.; Oldag, E. W.; Oliveira, R. A. N.; Olson, D.; Ostrowski, P.; Pachr, M.; Page, B. S.; Pal, S. K.; Pan, Y. X.; Pandit, Y.; Panebratsev, Y.; Pawlak, T.; Pawlik, B.; Pei, H.; Perkins, C.; Peryt, W.; Pile, P.; Planinic, M.; Pluta, J.; Plyku, D.; Poljak, N.; Porter, J.; Poskanzer, A. M.; Powell, C. B.; Prindle, D.; Pruneau, C.; Pruthi, N. K.; Przybycien, M.; Pujahari, P. R.; Putschke, J.; Qiu, H.; Raniwala, R.; Raniwala, S.; Ray, R. L.; Redwine, R.; Reed, R.; Riley, C. K.; Ritter, H. G.; Roberts, J. B.; Rogachevskiy, O. V.; Romero, J. L.; Ross, J. F.; Ruan, L.; Rusnak, J.; Sahoo, N. R.; Sakrejda, I.; Salur, S.; Sandacz, A.; Sandweiss, J.; Sangaline, E.; Sarkar, A.; Schambach, J.; Scharenberg, R. P.; Schmah, A. M.; Schmidke, B.; Schmitz, N.; Schuster, T. R.; Seele, J.; Seger, J.; Seyboth, P.; Shah, N.; Shahaliev, E.; Shao, M.; Sharma, B.; Sharma, M.; Shi, S. S.; Shou, Q. Y.; Sichtermann, E. P.; Singaraju, R. N.; Skoby, M. J.; Smirnov, D.; Smirnov, N.; Solanki, D.; Sorensen, P.; deSouza, U. G.; Spinka, H. M.; Srivastava, B.; Stanislaus, T. D. S.; Steadman, S. G.; Stevens, J. R.; Stock, R.; Strikhanov, M.; Stringfellow, B.; Suaide, A. A. P.; Suarez, M. C.; Sumbera, M.; Sun, X. M.; Sun, Y.; Sun, Z.; Surrow, B.; Svirida, D. N.; Symons, T. J. M.; Szanto de Toledo, A.; Takahashi, J.; Tang, A. H.; Tang, Z.; Tarini, L. H.; Tarnowsky, T.; Thein, D.; Thomas, J. H.; Tian, J.; Timmins, A. R.; Tlusty, D.; Tokarev, M.; Trainor, T. A.; Trentalange, S.; Tribble, R. E.; Tribedy, P.; Trzeciak, B. A.; Tsai, O. D.; Turnau, J.; Ullrich, T.; Underwood, D. G.; Van Buren, G.; van Nieuwenhuizen, G.; Vanfossen, J. A., Jr.; Varma, R.; Vasconcelos, G. M. S.; Videbæk, F.; Viyogi, Y. P.; Vokal, S.; Voloshin, S. A.; Vossen, A.; Wada, M.; Wang, F.; Wang, G.; Wang, H.; Wang, J. S.; Wang, Q.; Wang, X. L.; Wang, Y.; Webb, G.; Webb, J. C.; Westfall, G. D.; Whitten, C., Jr.; Wieman, H.; Wissink, S. W.; Witt, R.; Witzke, W.; Wu, Y. F.; Xiao, Z.; Xie, W.; Xin, K.; Xu, H.; Xu, N.; Xu, Q. H.; Xu, W.; Xu, Y.; Xu, Z.; Xue, L.; Yang, Y.; Yang, Y.; Yepes, P.; Yi, Y.; Yip, K.; Yoo, I.-K.; Zawisza, M.; Zbroszczyk, H.; Zhang, J. B.; Zhang, S.; Zhang, W. M.; Zhang, X. P.; Zhang, Y.; Zhang, Z. P.; Zhao, F.; Zhao, J.; Zhong, C.; Zhu, X.; Zhu, Y. H.; Zoulkarneeva, Y.

    2012-08-01

    We report on the mid-rapidity mass spectrum of di-electrons and cross sections of pseudoscalar and vector mesons via e+e- decays, from s=200 GeV p+p collisions, measured by the large-acceptance experiment STAR at the Relativistic Heavy Ion Collider. The ratio of the di-electron continuum to the combinatorial background is larger than 10% over the entire mass range. Simulations of di-electrons from light-meson decays and heavy-flavor decays (charmonium and open charm correlation) are found to describe the data. The extracted ω→e+e- invariant yields are consistent with previous measurements. The mid-rapidity yields (dN/dy) of φ and J/ψ are extracted through their di-electron decay channels and are consistent with the previous measurements of φ→K+K- and J/ψ→e+e-. Our results suggest a new upper limit of the branching ratio of the η→e+e- of 1.7×10-5 at the 90% confidence level.

  3. 40 CFR 721.1450 - 1,3-Benzenediamine, 4-(1,1-di-methylethyl)-ar-methyl.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 32 2012-07-01 2012-07-01 false 1,3-Benzenediamine, 4-(1,1-di-methylethyl)-ar-methyl. 721.1450 Section 721.1450 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC SUBSTANCES CONTROL ACT SIGNIFICANT NEW USES OF CHEMICAL SUBSTANCES Significant New Uses for Specific Chemical Substances §...

  4. 40 CFR 721.10483 - Siloxanes and Silicones, di-Me, Me vinyl, hydroxy-terminated, reaction products with...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... vinyl, hydroxy-terminated, reaction products with -modified silica. 721.10483 Section 721.10483... SIGNIFICANT NEW USES OF CHEMICAL SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.10483 Siloxanes and Silicones, di-Me, Me vinyl, hydroxy-terminated, reaction products with -modified silica....

  5. 40 CFR 721.10482 - Siloxanes and Silicones, di-Me, Me vinyl, hydroxy-terminated, reaction products with silica.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... CHEMICAL SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.10482 Siloxanes and Silicones, di-Me, Me vinyl, hydroxy-terminated, reaction products with silica. (a) Chemical substance and... vinyl, hydroxy-terminated, reaction products with silica. 721.10482 Section 721.10482 Protection...

  6. 40 CFR 721.10482 - Siloxanes and Silicones, di-Me, Me vinyl, hydroxy-terminated, reaction products with silica.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... CHEMICAL SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.10482 Siloxanes and Silicones, di-Me, Me vinyl, hydroxy-terminated, reaction products with silica. (a) Chemical substance and... vinyl, hydroxy-terminated, reaction products with silica. 721.10482 Section 721.10482 Protection...

  7. 40 CFR 721.10483 - Siloxanes and Silicones, di-Me, Me vinyl, hydroxy-terminated, reaction products with...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... vinyl, hydroxy-terminated, reaction products with -modified silica. 721.10483 Section 721.10483... SIGNIFICANT NEW USES OF CHEMICAL SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.10483 Siloxanes and Silicones, di-Me, Me vinyl, hydroxy-terminated, reaction products with -modified silica....

  8. Genome sequence of Ensifer medicae Di28; an effective N2-fixing microsymbiont of Medicago murex and M. polymorpha.

    PubMed

    Garau, Giovanni; Terpolilli, Jason; Hill, Yvette; Tian, Rui; Howieson, John; Bru, Lambert; Goodwin, Lynne; Han, James; Reddy, Tbk; Huntemann, Marcel; Pati, Amrita; Woyke, Tanja; Mavromatis, Konstantinos; Markowitz, Victor; Ivanova, Natalia; Kyrpides, Nikos; Reeve, Wayne

    2014-01-01

    Ensifer medicae Di28 is an aerobic, motile, Gram-negative, non-spore-forming rod that can exist as a soil saprophyte or as a legume microsymbiont of Medicago spp. Di28 was isolated in 1998 from a nodule recovered from the roots of M. polymorpha growing in the south east of Sardinia (Italy). Di28 is an effective microsymbiont of the annual forage legumes M. polymorpha and M. murex and is capable of establishing a partially effective symbiotic association with the perennial M. sativa. Here we describe the features of E. medicae Di28, together with genome sequence information and its annotation. The 6,553,624bp standard draft genome is arranged into 104 scaffolds of 104 contigs containing 6,394 protein-coding genes and 75 RNA-only encoding genes. This rhizobial genome is one of 100 sequenced as part of the DOE Joint Genome Institute 2010 Genomic Encyclopedia for Bacteria and Archaea-Root Nodule Bacteria (GEBA-RNB) project. PMID:25780497

  9. 40 CFR 721.1725 - Benzoic acid, 3,3′-methyl-enebis [6 amino-, di-2-propenyl ester.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 32 2013-07-01 2013-07-01 false Benzoic acid, 3,3â²-methyl-enebis [6 amino-, di-2-propenyl ester. 721.1725 Section 721.1725 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) TOXIC SUBSTANCES CONTROL ACT SIGNIFICANT NEW USES OF CHEMICAL SUBSTANCES Significant New Uses for Specific Chemical...

  10. Dicodon monitoring of protein synthesis (DiCoMPS) reveals levels of synthesis of a viral protein in single cells

    PubMed Central

    Barhoom, Sima; Farrell, Ian; Shai, Ben; Dahary, Dvir; Cooperman, Barry S.; Smilansky, Zeev; Elroy-Stein, Orna; Ehrlich, Marcelo

    2013-01-01

    The current report represents a further advancement of our previously reported technology termed Fluorescent transfer RNA (tRNA) for Translation Monitoring (FtTM), for monitoring of active global protein synthesis sites in single live cells. FtTM measures Förster resonance energy transfer (FRET) signals, generated when fluorescent tRNAs (fl-tRNAs), separately labeled as a FRET pair, occupy adjacent sites on the ribosome. The current technology, termed DiCodon Monitoring of Protein Synthesis (DiCoMPS), was developed for monitoring active synthesis of a specific protein. In DiCoMPS, specific fl-tRNA pair combinations are selected for transfection, based on the degree of enrichment of a dicodon sequence to which they bind in the mRNA of interest, relative to the background transcriptome of the cell in which the assay is performed. In this study, we used cells infected with the Epizootic Hemorrhagic Disease Virus 2-Ibaraki and measured, through DiCoMPS, the synthesis of the viral non-structural protein 3 (NS3), which is enriched in the AUA:AUA dicodon. fl-tRNAIleUAU-generated FRET signals were specifically enhanced in infected cells, increased in the course of infection and were diminished on siRNA-mediated knockdown of NS3. Our results establish an experimental approach for the single-cell measurement of the levels of synthesis of a specific viral protein. PMID:23965304

  11. Dicodon monitoring of protein synthesis (DiCoMPS) reveals levels of synthesis of a viral protein in single cells.

    PubMed

    Barhoom, Sima; Farrell, Ian; Shai, Ben; Dahary, Dvir; Cooperman, Barry S; Smilansky, Zeev; Elroy-Stein, Orna; Ehrlich, Marcelo

    2013-10-01

    The current report represents a further advancement of our previously reported technology termed Fluorescent transfer RNA (tRNA) for Translation Monitoring (FtTM), for monitoring of active global protein synthesis sites in single live cells. FtTM measures Förster resonance energy transfer (FRET) signals, generated when fluorescent tRNAs (fl-tRNAs), separately labeled as a FRET pair, occupy adjacent sites on the ribosome. The current technology, termed DiCodon Monitoring of Protein Synthesis (DiCoMPS), was developed for monitoring active synthesis of a specific protein. In DiCoMPS, specific fl-tRNA pair combinations are selected for transfection, based on the degree of enrichment of a dicodon sequence to which they bind in the mRNA of interest, relative to the background transcriptome of the cell in which the assay is performed. In this study, we used cells infected with the Epizootic Hemorrhagic Disease Virus 2-Ibaraki and measured, through DiCoMPS, the synthesis of the viral non-structural protein 3 (NS3), which is enriched in the AUA:AUA dicodon. fl-tRNA(Ile)UAU-generated FRET signals were specifically enhanced in infected cells, increased in the course of infection and were diminished on siRNA-mediated knockdown of NS3. Our results establish an experimental approach for the single-cell measurement of the levels of synthesis of a specific viral protein. PMID:23965304

  12. The Shell Seeker: What Is the Quantity of Shell in the Lido di Venezia Sand? A Calibration DRIFTS Experiment

    ERIC Educational Resources Information Center

    Pezzolo, Alessandra De Lorenzi

    2011-01-01

    In this experiment, students are given a fanciful application of the standard addition method to evaluate the approximate quantity of the shell component in a sample of sand collected on the Lido di Venezia seashore. Several diffuse reflectance infrared Fourier transform (DRIFT) spectra are recorded from a sand sample before and after addition of…

  13. 32 CFR 644.336 - Notices to Departments of Interior (DI); Health and Human Resources (HHR); Education; and Housing...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... ESTATE HANDBOOK Disposal Screening, Reassignment and Transfer of Real Property § 644.336 Notices to Departments of Interior (DI); Health and Human Resources (HHR); Education; and Housing and Urban Development... and Human Resources (HHR); Education; and Housing and Urban Development (HUD). 644.336 Section...

  14. 32 CFR 644.336 - Notices to Departments of Interior (DI); Health and Human Resources (HHR); Education; and Housing...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... ESTATE HANDBOOK Disposal Screening, Reassignment and Transfer of Real Property § 644.336 Notices to Departments of Interior (DI); Health and Human Resources (HHR); Education; and Housing and Urban Development... and Human Resources (HHR); Education; and Housing and Urban Development (HUD). 644.336 Section...

  15. 32 CFR 644.336 - Notices to Departments of Interior (DI); Health and Human Resources (HHR); Education; and Housing...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... ESTATE HANDBOOK Disposal Screening, Reassignment and Transfer of Real Property § 644.336 Notices to Departments of Interior (DI); Health and Human Resources (HHR); Education; and Housing and Urban Development... and Human Resources (HHR); Education; and Housing and Urban Development (HUD). 644.336 Section...

  16. Resonance Raman study of the A-band short-time photodissociation dynamics of 2,5-di-iodothiophene

    SciTech Connect

    Ruan Caibin; Zhu Hailin; Wang Huigang; Zheng Xuming; Phillips, David Lee

    2008-12-07

    Resonance Raman spectra were obtained for 2,5-di-iodothiophene in cyclohexane solution with excitation wavelengths in resonance with its A-band absorption. These spectra indicate that the Franck-Condon region photodissociation dynamics have multidimensional character with motion mostly along the nominal symmetric C{sub 2}C{sub 3}/C{sub 4}C{sub 5} stretch {nu}{sub 2} (1388 cm{sup -1}) of the thienyl ring and this is accompanied by motions along the nominal symmetric CSC stretch {nu}{sub 6} (640 cm{sup -1}), the nominal symmetric C-I stretch {nu}{sub 7} (187 cm{sup -1}), the nominal antisymmetric CSC stretch {nu}{sub 19} (728 cm{sup -1}), the nominal antisymmetric C{sub 2}C{sub 3}/C{sub 4}C{sub 5} stretch {nu}{sub 16} (1497 cm{sup -1}), the nominal C{sub 3}C{sub 4} stretch {nu}{sub 3} (1286 cm{sup -1}) and four other vibrational modes. A preliminary resonance Raman intensity analysis was done and the results for 2,5-di-iodothiophene were compared to previous results for 2-iodothiophene and di-iodomethane to discuss the mechanism of the symmetric breaking in the initial A-band photodissociation dynamics of 2,5-di-iodothiophene and 2-iodothiophene.

  17. An unexpected transmetalation intermediate: isolation and structural characterization of a solely CH3 bridged di-copper(i) complex.

    PubMed

    Molteni, Roberto; Bertermann, Rüdiger; Edkins, Katharina; Steffen, Andreas

    2016-04-11

    Structural characterization of unsupported, two metal centres bridging methyl groups is rare. They have been proposed as transmetalation intermediates in cuprate chemistry, but as yet no structural evidence has been presented. We have isolated a di-copper(i) complex with solely a methyl ligand bridging two Cu(i) atoms, representing a new bonding mode of CH3. PMID:26983362

  18. The Shell Seeker: What Is the Quantity of Shell in the Lido di Venezia Sand? A Calibration DRIFTS Experiment

    ERIC Educational Resources Information Center

    Pezzolo, Alessandra De Lorenzi

    2011-01-01

    In this experiment, students are given a fanciful application of the standard addition method to evaluate the approximate quantity of the shell component in a sample of sand collected on the Lido di Venezia seashore. Several diffuse reflectance infrared Fourier transform (DRIFT) spectra are recorded from a sand sample before and after addition of

  19. A Bayes Factor Meta-Analysis of Recent Extrasensory Perception Experiments: Comment on Storm, Tressoldi, and Di Risio (2010)

    ERIC Educational Resources Information Center

    Rouder, Jeffrey N.; Morey, Richard D.; Province, Jordan M.

    2013-01-01

    Psi phenomena, such as mental telepathy, precognition, and clairvoyance, have garnered much recent attention. We reassess the evidence for psi effects from Storm, Tressoldi, and Di Risio's (2010) meta-analysis. Our analysis differs from Storm et al.'s in that we rely on Bayes factors, a Bayesian approach for stating the evidence from data for

  20. Achromobactor denitrificans SP1 produces pharmaceutically active 25C prodigiosin upon utilizing hazardous di(2-ethylhexyl)phthalate

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Achromobacter denitrificans SP1 isolated from soil sludge heavily contaminated with plastic waste produced a novel pharmaceutically-active 25C prodigiosin analog during growth in a simple mineral salt medium supplemented with hazardous di(2-ethylhexyl)phthalate (DEHP) blended PVC plastics (in situ) ...

  1. Preparation and characterization of di-, tri-, and tetranuclear schiff base complexes derived from diamines and 3,4-dihydroxybenzaldehyde.

    PubMed

    Abdulghani, Ahlam Jameel; Khaleel, Asmaa Mohammed Noori

    2013-01-01

    A series of new di-, tri-, and tetranuclear Co(II) and Cu(II) complexes of three new diSchiff base ligands were synthesized by two different methods. The first method involved the synthesis of the three ligands from condensation reaction of 3,4-dihydroxybenzaldehyde (L'H2) with ethylenediamine (en), o-phenylenediamine (o-PD), or 4,5-dimethyl-1,2-phenylendiamine (DMPD) in a mole ratio of 2 : 1 followed by the reaction of the resulting Schiff bases ligands with Cu(II) or Co(II) ions in the presence of 2,2'-bipyridyl (L) to form the di- and trinuclear metal complexes. The second method involved the condensation of the copper complex LCu(II)L' (L = 2,2'-bipyridyl, L' = 4-formylbenzene-1,2-bis(olate)) with en, o-PD, or DMPD in a mole ratio of 2 : 1, respectively, followed by reaction with CuCl2 or Cu(ClO4)2 to form di-, tri-, and tetranuclear copper (II) complexes, respectively. The structures of the ligands and metal complexes were characterized by elemental analyses, NMR, and FTIR spectra. The geometries of metal complexes were suggested according to elemental analysis, electronic spectra, thermal analyses, atomic absorption, and magnetic moments and conductivity measurements. PMID:24453995

  2. A Study of the Contribution from Non-Perturbative Effects to Di-jet Yields at Forward Rapidity

    NASA Astrophysics Data System (ADS)

    Poulsen, Anna; Chang, Zilong; Gagliardi, Carl; Gagliardi Team

    2015-10-01

    It is well known that the proton's spin is equal to ℏ/2, but its internal structure and the spin contributions made by its parton constituents, especially gluons, remain enigmatic. By studying asymmetric di-jets produced in polarized proton-proton collisions at forward rapidity, more information about the spin contribution of the gluon can be attained. Next-to-leading order perturbative QCD calculations indicate that measurements of di-jets at forward rapidity with transverse momenta of 5 and 8 GeV/c can provide valuable information regarding the gluon polarization. However these calculations do not include background contributions from initial state-radiation, underlying events and beam remnants that can create additional particles which appear in the detector as jets. In this study, PYTHIA simulations were used to analyze jets of stable final state hadrons. A simple procedure is found to reject the background. Most of the di-jets that remain can be matched to initial hard scattered partons with momentum fractions x2 of the order 10-3 and x1 of 0.4 or greater. These kinematics indicate that the remaining di-jets will provide relevant information about the gluon's polarization and lead to a better understanding of the proton's structure at the partonic level. This material is based upon work supported by the National Science Foundation Graduate Research Fellowship under Grant No. 1263281.

  3. A Bayes Factor Meta-Analysis of Recent Extrasensory Perception Experiments: Comment on Storm, Tressoldi, and Di Risio (2010)

    ERIC Educational Resources Information Center

    Rouder, Jeffrey N.; Morey, Richard D.; Province, Jordan M.

    2013-01-01

    Psi phenomena, such as mental telepathy, precognition, and clairvoyance, have garnered much recent attention. We reassess the evidence for psi effects from Storm, Tressoldi, and Di Risio's (2010) meta-analysis. Our analysis differs from Storm et al.'s in that we rely on Bayes factors, a Bayesian approach for stating the evidence from data for…

  4. Using Expansion Strategies in Making Untranslatable Areas of Poetry Translatable: Sa'di's Bustan as a Case in Point

    ERIC Educational Resources Information Center

    Shirinzadeh, Seyed Alireza; Mahadi, Tengku Sepora Tengku

    2014-01-01

    The purpose of this study was to explore poetry translatability and seek to see what the translators do to compensate those untranslatable areas of poetry. In doing so, the researchers chose a literary work, i.e., Bustan, by one of the well-known Iranian poets, that is, Sa'di (Wickens, 1990) and one of its translations, "The Bustan by Shaikh…

  5. Synthesis of Triazole-Linked Analogues of c-di-GMP and Their Interactions with Diguanylate Cyclase.

    PubMed

    Fernicola, Silvia; Torquati, Ilaria; Paiardini, Alessandro; Giardina, Giorgio; Rampioni, Giordano; Messina, Marco; Leoni, Livia; Del Bello, Fabio; Petrelli, Riccardo; Rinaldo, Serena; Cappellacci, Loredana; Cutruzzolà, Francesca

    2015-10-22

    Cyclic di-GMP (c-di-GMP) is a widespread second messenger that plays a key role in bacterial biofilm formation. The compound's ability to assume multiple conformations allows it to interact with a diverse set of target macromolecules. Here, we analyzed the binding mode of c-di-GMP to the allosteric inhibitory site (I-site) of diguanylate cyclases (DGCs) and compared it to the conformation adopted in the catalytic site of the EAL phosphodiesterases (PDEs). An array of novel molecules has been designed and synthesized by simplifying the native c-di-GMP structure and replacing the charged phosphodiester backbone with an isosteric nonhydrolyzable 1,2,3-triazole moiety. We developed the first neutral small molecule able to selectively target DGCs discriminating between the I-site of DGCs and the active site of PDEs; this molecule represents a novel tool for mechanistic studies, particularly on those proteins bearing both DGC and PDE modules, and for future optimization studies to target DGCs in vivo. PMID:26426545

  6. r-bPiDI, an α6β2* Nicotinic Receptor Antagonist, Decreases Nicotine-Evoked Dopamine Release and Nicotine Reinforcement.

    PubMed

    Beckmann, Joshua S; Meyer, Andrew C; Pivavarchyk, M; Horton, David B; Zheng, Guangrong; Smith, Andrew M; Wooters, Thomas E; McIntosh, J Michael; Crooks, Peter A; Bardo, Michael T; Dwoskin, Linda P

    2015-10-01

    α6β2* nicotinic acetylcholine receptors (nAChRs) expressed by dopaminergic neurons mediate nicotine-evoked dopamine (DA) release and nicotine reinforcement. α6β2* antagonists inhibit these effects of nicotine, such that α6β2* receptors serve as therapeutic targets for nicotine addiction. The present research assessed the neuropharmacology of 1,10-bis(3-methyl-5,6-dihydropyridin-1(2H)-yl)decane (r-bPiDI), a novel small-molecule, tertiary amino analog of its parent compound, N,N-decane-1,10-diyl-bis-3-picolinium diiodide (bPiDI). bPiDI was previously shown to inhibit both nicotine-evoked DA release and the reinforcing effects of nicotine. In the current study, r-bPiDI inhibition of [(3)H]nicotine and [(3)H]methyllycaconitine binding sites was evaluated to assess interaction with the recognition binding sites on α4β2* and α7* nAChRs, respectively. Further, r-bPiDI inhibition of nicotine-evoked DA release in vitro in the absence and presence of α-conotoxin MII and following chronic in vivo nicotine administration were determined. The ability of r-bPiDI to decrease nicotine self-administration and food-maintained responding was also assessed. Results show that r-bPiDI did not inhibit [(3)H]nicotine or [(3)H]methyllycaconitine binding, but potently (IC50 = 37.5 nM) inhibited nicotine-evoked DA release from superfused striatal slices obtained from either drug naïve rats or from those repeatedly treated with nicotine. r-bPiDI inhibition of nicotine-evoked DA release was not different in the absence or presence of α-conotoxin MII, indicating that r-bPiDI acts as a potent, selective α6β2* nAChR antagonist. Acute systemic administration of r-bPiDI specifically decreased nicotine self-administration by 75 %, and did not alter food-maintained responding, demonstrating greater specificity relative to bPiDI and bPiDDB, as well as the tertiary amino analog r-bPiDDB. The current work describes the discovery of r-bPiDI, a tertiary amino, α-conotoxin MII-like small molecule that acts as a potent and selective antagonist at α6β2* nAChRs to specifically decrease nicotine self-administration in rats, thus, establishing r-bPiDI as a lead compound for development as a treatment for nicotine addiction. PMID:26227997

  7. Di-22:6-bis(monoacylglycerol)phosphate: A clinical biomarker of drug-induced phospholipidosis for drug development and safety assessment

    SciTech Connect

    Liu, Nanjun; Tengstrand, Elizabeth A.; Chourb, Lisa; Hsieh, Frank Y.

    2014-09-15

    The inability to routinely monitor drug-induced phospholipidosis (DIPL) presents a challenge in pharmaceutical drug development and in the clinic. Several nonclinical studies have shown di-docosahexaenoyl (22:6) bis(monoacylglycerol) phosphate (di-22:6-BMP) to be a reliable biomarker of tissue DIPL that can be monitored in the plasma/serum and urine. The aim of this study was to show the relevance of di-22:6-BMP as a DIPL biomarker for drug development and safety assessment in humans. DIPL shares many similarities with the inherited lysosomal storage disorder Niemann–Pick type C (NPC) disease. DIPL and NPC result in similar changes in lysosomal function and cholesterol status that lead to the accumulation of multi-lamellar bodies (myeloid bodies) in cells and tissues. To validate di-22:6-BMP as a biomarker of DIPL for clinical studies, NPC patients and healthy donors were classified by receiver operator curve analysis based on urinary di-22:6-BMP concentrations. By showing 96.7-specificity and 100-sensitivity to identify NPC disease, di-22:6-BMP can be used to assess DIPL in human studies. The mean concentration of di-22:6-BMP in the urine of NPC patients was 51.4-fold (p ≤ 0.05) above the healthy baseline range. Additionally, baseline levels of di-22:6-BMP were assessed in healthy non-medicated laboratory animals (rats, mice, dogs, and monkeys) and human subjects to define normal reference ranges for nonclinical/clinical studies. The baseline ranges of di-22:6-BMP in the plasma, serum, and urine of humans and laboratory animals were species dependent. The results of this study support the role of di-22:6-BMP as a biomarker of DIPL for pharmaceutical drug development and health care settings. - Highlights: • A reliable biomarker of drug-induced phospholipidosis (DIPL) is needed for humans. • Di-22:6-BMP is specific/sensitive for DIPL in animals as published in literatures. • The di-22:6-BMP biomarker can be validated for humans via NPC patients. • DIPL shares morphologic/mechanistic similarities with Niemann–Pick type C disease. • Di-22:6-BMP is an effective DIPL biomarker in humans via NPC patient validation.

  8. Future prospects for stau in Higgs coupling to di-photon

    NASA Astrophysics Data System (ADS)

    Endo, Motoi; Kitahara, Teppei; Yoshinaga, Takahiro

    2014-04-01

    We study future prospects of the stau which contributes to the Higgs coupling to di-photon. The coupling is sensitive to new physics and planned to be measured at percent levels in future colliders. We show that, if the excess of the coupling is measured to be larger than 4%, the lightest stau is predicted to be lighter than about 200 GeV by taking vacuum meta-stability conditions into account. Such a stau can be discovered at ILC. Moreover, we show how accurately the stau contribution to the coupling can be reconstructed from the information that is available at ILC. We also argue that, if the stau mixing angle is measured, the mass of the heaviest stau can be predicted by measuring the Higgs coupling, even when the heaviest stau is not yet discovered at the early stage of ILC.

  9. Bis[(di-methyl-phosphor-yl)methan-amin-ium] tetra-chlorido-palladate(II).

    PubMed

    Reiss, Guido J

    2013-10-19

    In the crystal structure of the title compound, (C3H11NOP)2[PdCl4], (di-methyl-phosphor-yl)methanaminium (dpmaH(+)) cations are connected head-to-tail by strong N-H⋯O hydrogen bonds, forming inversion-related cyclic dimers. The square-planar [PdCl4](2-) counter-dianion is located about a center of inversion. The dications and the [PdCl4](2-) dianions are connected by medium-strong N-H⋯Cl hydrogen bonds, forming zigzag chains parallel to [001]. Somewhat weaker N-H⋯Cl hydrogen bonds connect the chains into a three-dimensional network. PMID:24454042

  10. Bio-Source of di-n-butyl phthalate production by filamentous fungi

    PubMed Central

    Tian, Congkui; Ni, Jinren; Chang, Fang; Liu, Sitong; Xu, Nan; Sun, Weiling; Xie, Yuan; Guo, Yongzhao; Ma, Yanrong; Yang, Zhenxing; Dang, Chenyuan; Huang, Yuefei; Tian, Zhexian; Wang, Yiping

    2016-01-01

    Although DBP (di-n-butyl phthalate) is commonly encountered as an artificially-synthesized plasticizer with potential to impair fertility, we confirm that it can also be biosynthesized as microbial secondary metabolites from naturally occurring filamentous fungi strains cultured either in an artificial medium or natural water. Using the excreted crude enzyme from the fungi for catalyzing a variety of substrates, we found that the fungal generation of DBP was largely through shikimic acid pathway, which was assembled by phthalic acid with butyl alcohol through esterification. The DBP production ability of the fungi was primarily influenced by fungal spore density and incubation temperature. This study indicates an important alternative natural waterborne source of DBP in addition to artificial synthesis, which implied fungal contribution must be highlighted for future source control and risk management of DBP. PMID:26857605

  11. Crystal structure of 2,2-di­phenyl­hydrazinium chloride

    PubMed Central

    Paul, Amit Kumal; Mukherjee, Soma; Stoeckli-Evans, Helen

    2014-01-01

    In the title compound, C12H13N2 +·Cl−, the chloride salt of 1,1′-di­phenyl­hydrazine, the phenyl rings are inclined to one another by 78.63 (17)°. The N—+NH3 bond lengths is 1.445 (3) Å, and the N—Cphen­yl bond lengths are 1.435 (3) and 1.447 (4) Å. In the crystal, mol­ecules are linked via N—H⋯Cl hydrogen bonds, forming chains along [10-1], which enclose two adjacent R 4 2(6) ring motifs. The chains are reinforced by C—H⋯Cl hydrogen bonds. PMID:25484752

  12. 1,5-Di(nitramino)tetrazole: High Sensitivity and Superior Explosive Performance.

    PubMed

    Fischer, Dennis; Klapötke, Thomas M; Stierstorfer, Jörg

    2015-08-24

    Highly energetic 1,5-di(nitramino)tetrazole and its salts were synthesized. The neutral compound is very sensitive and one of the most powerful non-nuclear explosives to date. Selected nitrogen-rich and metal salts were prepared. The potassium salt can be used as a sensitizer in place of tetracene. The obtained compounds were characterized by low-temperature X-ray diffraction, IR and Raman spectroscopy, multinuclear NMR spectroscopy, elemental analysis, and DSC. Calculated energetic performances using the EXPLO5 code based on calculated (CBS-4M) heats of formation and X-ray densities support the high energetic performances of the 1,5-dinitraminotetrazolates as energetic materials. The sensitivities towards impact, friction, and electrostatic discharge were also explored. PMID:26095124

  13. Bio-Source of di-n-butyl phthalate production by filamentous fungi

    NASA Astrophysics Data System (ADS)

    Tian, Congkui; Ni, Jinren; Chang, Fang; Liu, Sitong; Xu, Nan; Sun, Weiling; Xie, Yuan; Guo, Yongzhao; Ma, Yanrong; Yang, Zhenxing; Dang, Chenyuan; Huang, Yuefei; Tian, Zhexian; Wang, Yiping

    2016-02-01

    Although DBP (di-n-butyl phthalate) is commonly encountered as an artificially-synthesized plasticizer with potential to impair fertility, we confirm that it can also be biosynthesized as microbial secondary metabolites from naturally occurring filamentous fungi strains cultured either in an artificial medium or natural water. Using the excreted crude enzyme from the fungi for catalyzing a variety of substrates, we found that the fungal generation of DBP was largely through shikimic acid pathway, which was assembled by phthalic acid with butyl alcohol through esterification. The DBP production ability of the fungi was primarily influenced by fungal spore density and incubation temperature. This study indicates an important alternative natural waterborne source of DBP in addition to artificial synthesis, which implied fungal contribution must be highlighted for future source control and risk management of DBP.

  14. Erosion results from DiMES and design implications to ITER and Starlite

    SciTech Connect

    Wong, C.P.C.; West, W.P.; Whyte, D.G.; Bastaz, R.J.; Wampler, W.R.

    1996-12-31

    Using the DiMES mechanism at DIII-D, erosion rates of graphite, and metallic coatings of Be, V, Mo, and W have been measured under different plasma operating conditions. The measured net erosion rate for C is substantial (16 nm/s) during ELMing H-mode at a heat flux of 2 MW/m{sup 2}. Measured gross erosion rates of the metals are lower than expected from sputtering yields, most likely due to heavy surface contamination by carbon. The measured erosion of W is substantially lower than the other materials, and when account is taken for redeposition, it is shown to be a viable candidate for the Starlite reactor`s divertor. 15 refs., 1 fig., 1 tab.

  15. Erosion results from DiMES and design implications to ITER and Starlite

    SciTech Connect

    Wong, C.P.C.; West, W.P.; Bastaz, R.J.; Whyte, D.G.; Wampler, W.R.

    1996-07-01

    Using the DiMES mechanism at DIII-D, erosion rates of graphite, and metallic coatings of Be, V, Mo, and W have been measured under different plasma operating conditions. The measured net erosion rate for C is substantial (16 nm/s) during ELMing H-mode at a heat flux of 2 MW/m{sup 2}. Measured gross erosion rates of the metals are lower than expected from sputtering yields, most likely due to heavy surface contamination by carbon. The measured erosion of W is substantially lower than the other materials, and when account is taken for redeposition, it is shown to be a viable candidate for the Starlite reactor`s divertor.

  16. Investigation and application of multiple reactions between molybdoniobium heteropoly acid and di- or trimethylthionines

    SciTech Connect

    Mirzoyam, F.B.; Karapetyan, A.A.

    1986-03-01

    This paper presents the results of the study and use of reactions of molybdoniobic acid (MNA) with di- and trimethylthiones (DMT and TMT, respectively). It was found that light absorption of acetone solutions of the products of outer-sphere interaction between MNA and DMT or TMT enabled the determination of optimum acidity for MNA formation. Reaction between TMT and MNA gives two different compounds containing two and five associated dye cations, different in molar extinction coefficient and optimum reaction acidity (pH 0.05-0.25 and 0.35-0.90). Formation of the 6th and 8th molybdenum series with an identical composition of the outer sphere is shown. A highly sensitive photometric method for determining niobium has been developed.

  17. Introspection on improper seismic retrofit of Basilica Santa Maria di Collemaggio after 2009 Italian earthquake

    NASA Astrophysics Data System (ADS)

    Cimellaro, Gian Paolo; Reinhorn, Andrei M.; de Stefano, Alessandro

    2011-03-01

    The 2009 L'Aquila, Italy earthquake highlighted the seismic vulnerability of historic masonry building structures due to improper "strengthening" retrofit work that has been done in the last 50 years. Italian seismic standards recommend the use of traditional reinforcement techniques such as replacing the original wooden roof structure with new reinforced concrete (RC) or steel elements, inserting RC tie-beams in the masonry and new RC floors, and using RC jacketing on the shear walls. The L'Aquila earthquake revealed the numerous limitations of these interventions, because they led to increased seismic forces (due to greater additional weight) and to deformation incompatibilities of the incorporated elements with the existing masonry walls. This paper provides a discussion of technical issues pertaining to the seismic retrofit of the Santa Maria di Collemaggio Basilica and in particular, the limitations of the last (2000) retrofit intervention. Considerable damage was caused to the church because of questionable actions and incorrect and improper technical choices.

  18. The apsidal motion of the eccentric eclipsing binary DI Herculis - An apparent discrepancy with general relativity

    NASA Technical Reports Server (NTRS)

    Guinan, E. F.; Maloney, F. P.

    1985-01-01

    The apsidal motion of the eccentric eclipsing binary DI Herculis (HD 175227) is determined from an analysis of the available observations and eclipse timings from 1959 to 1984. Least squares solutions to the primary and secondary minima extending over an 84-yr interval yielded a small advance of periastron omega dot of 0.65 deg/100 yr + or - 0.18/100 yr. The observed advance of the periastron is about one seventh of the theoretical value of 4.27 deg/100 yr that is expected from the combined relativistic and classical effects. The discrepancy is about -3.62 deg/100 yr, or a magnitude of about 20 sigma. Classical mechanisms which explain the discrepancy are discussed, together with the possibility that there may be problems with general relativity itself.

  19. Survey of di-(2-ethylhexyl)phthalate plasticizer contamination of retail Danish milks.

    PubMed

    Petersen, J H

    1991-01-01

    An investigation of residues of di-(2-ethylhexyl)-phthalate (DEHP) in retail whole milk in samples from one German and 14 Danish dairies is reported. The investigation was performed about six months after the use of DEHP-plasticized milk tubing was banned in Denmark. The results indicate a mean concentration of DEHP lower than 50 micrograms/litre in retail whole milk. Based on these data and the Tolerable Daily Intake (TDI) for DEHP of 25 micrograms/kg body weight laid down by the EEC Scientific Committee for Food, it is concluded that the intake of DEHP from milk and milk products does not, even through a whole life, constitute a danger to health for the Danish population. PMID:1812016

  20. Modeling of nickel extraction between Di-n-butyl phosphorodithioate and acid

    SciTech Connect

    Bogacki, M.B.; Szymanowski, J. . Inst. of Chemical Technology and Engineering); Cote, G. . Lab. de Chimie Analytique)

    1993-11-01

    A chemical model for nickel(II) extraction from acidic sulfate solutions with O,O-di-n-butyl phosphorodithioate and for nickel stripping with hydrochloric acid solutions is presented and used for discussion of extraction-stripping systems with either conventional sequential stages of extraction and stripping or unconventional cross-current flows. A good agreement of the model with experimental extraction data is observed. The number of extraction and stripping stages necessary to obtain a given yield of transfer of nickel(II) has been found to be lower in unconventional extraction-stripping systems than in conventional systems with sequential stages of extraction and stripping. The use of hydrochloric acid for stripping instead of sulfuric acid leads to an important increase of nickel transfer from the feed to the strip liquor.