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Sample records for 2a 2b 2c

  1. Vaccination of dogs with canine parvovirus type 2b (CPV-2b) induces neutralising antibody responses to CPV-2a and CPV-2c.

    PubMed

    Wilson, Stephen; Illambas, Joanna; Siedek, Elisabeth; Stirling, Catrina; Thomas, Anne; Plevová, Edita; Sture, Gordon; Salt, Jeremy

    2014-09-22

    Since the identification of canine parvovirus type 2, three variants have subsequently been observed differing from the historical CPV-2 and each other by 1-2 amino acids only. As a result there has been considerable research into differential diagnostics, with some researchers indicating there is a need for new vaccines containing different strains of CPV-2. In this study we investigated whether vaccination with a CPV-2b containing vaccine would induce cross-reactive antibody responses to the other CPV-2 variants. Two studies where dogs were vaccinated with a multivalent vaccine, subsequently challenged with CPV-2b and sera samples analysed are presented. Six week old pups with defined serological status were vaccinated twice, three weeks apart and challenged either 5 weeks (MDA override study) or one year after vaccination (duration of immunity study). Sera samples were collected before each vaccination and at periods throughout each study. In each study the antibody profiles were very similar; serological responses against CPV-2a, CPV-2b and CPV-2c were higher than those for CPV-2. Nevertheless, responses against CPV-2 were well above levels considered clinically protective. In each study dogs also showed a rapid increase in antibody titres following vaccination, reached a plateau following second vaccination with a slight decline to challenge after which rapid anamnestic responses were seen. Evaluation of the serological responses suggests vaccination with CPV-2b would cross-protect against CPV-2a and CPV-2c, as well as against CPV-2 which is now extinct in the field. In conclusion we have demonstrated that vaccination of minimum aged dogs with a multivalent vaccine containing the CPV-2b variant strain will induce serological responses which are cross-reactive against all currently circulating field strains, CPV-2a and CPV-2c, and the now extinct field strain CPV-2. PMID:25148778

  2. Vaccination of dogs with canine parvovirus type 2b (CPV-2b) induces neutralising antibody responses to CPV-2a and CPV-2c.

    PubMed

    Wilson, Stephen; Illambas, Joanna; Siedek, Elisabeth; Stirling, Catrina; Thomas, Anne; Plevová, Edita; Sture, Gordon; Salt, Jeremy

    2014-09-22

    Since the identification of canine parvovirus type 2, three variants have subsequently been observed differing from the historical CPV-2 and each other by 1-2 amino acids only. As a result there has been considerable research into differential diagnostics, with some researchers indicating there is a need for new vaccines containing different strains of CPV-2. In this study we investigated whether vaccination with a CPV-2b containing vaccine would induce cross-reactive antibody responses to the other CPV-2 variants. Two studies where dogs were vaccinated with a multivalent vaccine, subsequently challenged with CPV-2b and sera samples analysed are presented. Six week old pups with defined serological status were vaccinated twice, three weeks apart and challenged either 5 weeks (MDA override study) or one year after vaccination (duration of immunity study). Sera samples were collected before each vaccination and at periods throughout each study. In each study the antibody profiles were very similar; serological responses against CPV-2a, CPV-2b and CPV-2c were higher than those for CPV-2. Nevertheless, responses against CPV-2 were well above levels considered clinically protective. In each study dogs also showed a rapid increase in antibody titres following vaccination, reached a plateau following second vaccination with a slight decline to challenge after which rapid anamnestic responses were seen. Evaluation of the serological responses suggests vaccination with CPV-2b would cross-protect against CPV-2a and CPV-2c, as well as against CPV-2 which is now extinct in the field. In conclusion we have demonstrated that vaccination of minimum aged dogs with a multivalent vaccine containing the CPV-2b variant strain will induce serological responses which are cross-reactive against all currently circulating field strains, CPV-2a and CPV-2c, and the now extinct field strain CPV-2.

  3. Telecom 2-B and 2-C (TC2B and TC2C)

    NASA Technical Reports Server (NTRS)

    Dulac, J.; Alvarez, H.

    1991-01-01

    The DSN (Deep Space Network) mission support requirements for Telecom 2-B and 2-C (TC2B and TC2C) are summarized. These Telecom missions will provide high-speed data link applications, telephone, and television service between France and overseas territories as a follow-on to TC2A. Mission objectives are outlined and the DSN support requirements are defined through the presentation of tables and narratives describing the spacecraft flight profile; DSN support coverage; frequency assignments; support parameters for telemetry, command and support systems; and tracking support responsibility.

  4. PHOX2A and PHOX2B are differentially regulated during retinoic acid-driven differentiation of SK-N-BE(2)C neuroblastoma cell line

    PubMed Central

    Di Lascio, Simona; Saba, Elena; Belperio, Debora; Raimondi, Andrea; Lucchetti, Helen; Fornasari, Diego; Benfante, Roberta

    2016-01-01

    PHOX2B and its paralogue gene PHOX2A are two homeodomain proteins in the network regulating the development of autonomic ganglia that have been associated with the pathogenesis of neuroblastoma (NB), because of their over-expression in different NB cell lines and tumour samples. We used the SK-N-BE(2)C cell line to show that all-trans retinoic acid (ATRA), a drug that is widely used to inhibit growth and induce differentiation in NBs, regulates both PHOX2A and PHOX2B expression, albeit by means of different mechanisms: it up-regulates PHOX2A and down-regulates PHOX2B. Both mechanisms act at transcriptional level, but prolonged ATRA treatment selectively degrades the PHOX2A protein, whereas the corresponding mRNA remains up-regulated. Further, we show that PHOX2A is capable of modulating PHOX2B expression, but this mechanism is not involved in the PHOX2B down-regulation induced by retinoic acid. Our findings demonstrate that PHOX2A expression is finely controlled during retinoic acid differentiation and this, together with PHOX2B down-regulation, reinforces the idea that they may be useful biomarkers for NB staging, prognosis and treatment decision making. PMID:26902400

  5. Roles of human CYP2A6 and 2B6 and rat CYP2C11 and 2B1 in the 10-hydroxylation of (-)-verbenone by liver microsomes.

    PubMed

    Miyazawa, Mitsuo; Sugie, Atsushi; Shimada, Tsutomu

    2003-08-01

    (-)-Verbenone, a monoterpene bicyclic ketone, is a component of the essential oil from rosemary species such as Rosmarinus officinalis L., Verbena triphylla, and Eucalyptus globulus and is used for an herb tea, a spice, and a perfume. In this study, (-)-verbenone was found to be converted to 10-hydroxyverbenone by rat and human liver microsomal cytochrome p450 (p450) enzymes. The product formation was determined by high-performance liquid chromatography with UV detection at 251 nm. There was a good correlation between activities of coumarin 7-hydroxylation and (-)-verbenone 10-hydroxylation catalyzed by liver microsomes of 16 human samples, indicating that CYP2A6 is a principal enzyme in (-)-verbenone 10-hydroxylation in humans. Human recombinant CYP2A6 and CYP2B6 catalyzed (-)verbenone 10-hydroxylation at Vmax values of 15 and 21 nmol/min/nmol p450 with apparent Km values of 16 and 91 microM, respectively. In contrast, rat CYP2A1 and 2A2 did not catalyze (-)-verbenone 10-hydroxylation at all, suggesting that there were species-related differences in the catalytic properties of human and rat CYP2A enzymes in the metabolism of (-)-verbenone. In the rat, recombinant CYP2C11, CYP2B1, and CYP3A2 catalyzed (-)-verbenone 10-hydroxylation with Vmax and Km ratios (ml/min/nmol p450) of 0.73, 0.20, and 0.03, respectively. Male-specific CYP2C11 was a major enzyme in (-)-verbenone 10-hydroxylation by untreated rat livers, and CYP2B1 catalyzed this reaction in liver microsomes of phenobarbital-treated rats. Rat CYP2C12, a female-specific enzyme, did not catalyze (-)verbenone 10-hydroxylation. These results suggest that human CYP2A6 and rat CYP2C11 are the major catalysts in the metabolism of (-)-verbenone by liver microsomes and that there are species-related differences in human and rat CYP2A enzymes and sex-related differences in male and female rats in the metabolism of (-)-verbenone.

  6. A study of presynaptic alpha2-autoreceptors in alpha2A/D-, alpha2B- and alpha2C-adrenoceptor-deficient mice.

    PubMed

    Trendelenburg, A U; Klebroff, W; Hein, L; Starke, K

    2001-08-01

    The function of presynaptic alpha2-autoreceptors was studied in the hippocampus, occipito-parietal cortex, atria and vas deferens of NMRI mice, mice in which the alpha2A/D-, the alpha2B- or alpha2c-adrenoceptor gene had been disrupted (alpha2A/DKO, alpha2BKO and alpha2CKO, respectively), and the wildtype mice from which the knockout animals had been generated. Tissue pieces were preincubated with 3H-noradrenaline and then superfused and stimulated electrically. The alpha2-adrenoceptor agonist medetomidine reduced the electrically evoked overflow of tritium in all tissues from all mouse strains (stimulation with single pulses or single high-frequency pulse trains, called POPs, i.e. pulse patterns leading to minimal autoinhibition). The effects of medetomidine did not differ in NMRI, wildtype, alpha2BKO and alpha2CKO mice but were greatly reduced in alpha2A/DKO brain preparations and to a lesser extent in alpha2A/DKO atria and vasa deferentia. Six drugs were tested as antagonists against medetomidine. Their pKd values indicated that the hippocampal and occipito-parietal alpha2-autoreceptors in NMRI and wildtype mice were alpha2D (the rodent variant of the alpha2A/D-adrenoceptor) whereas the atrial and vas deferens alpha2-autoreceptors in NMRI and wildtype mice could not be identified with a single alpha2 subtype. Deletion of the alpha2A/D gene changed the pKd values in all tissues so that they now reflected alpha2C properties, whereas deletion of the alpha2C gene changed the pKd values in atria and vasa deferentia so that they now had alpha2D properties (as they had in NMRI and wildtype brain preparations). Autoinhibition by released noradrenaline was created using trains of up to 64 pulses or up to 4 POPs, and the overflow-enhancing effect of the alpha2 antagonist rauwolscine was determined. Results did not differ, irrespective of whether preparations were obtained from NMRI, wildtype, alpha2BKO or alpha2CKO mice: the overflow of tritium elicited by p pulses or POPs

  7. The relative cellular levels of CP2a and CP2b potentiates erythroid cell-specific expression of the {alpha}-globin gene by regulating the nuclear localization of CP2c

    SciTech Connect

    Chae, Ji Hyung; Kang, Ho Chul; Kim, Chul Geun

    2009-03-20

    CP2b activates {alpha}-globin expression in an erythroid cell-specific manner, through interaction with CP2c and PIAS1. Although CP2a is identical to CP2b except for lacking an exon encoding additional 36 amino acids and has the intrinsic DNA binding and transactivation properties, it does not exert any role in {alpha}-globin expression. Investigation of subcellular localization of exogenous CP2 proteins revealed that CP2a and CP2b were exclusively localized in the cytosol and nucleus, respectively. The CP2b-specific exon was in charge of the nuclear localization of CP2b. Interestingly, subcellular localization of CP2c was either in the nucleus or cytosol depending on the relative level of CP2a and CP2b although CP2c intrinsically localized in the cytosol in the absence of CP2a/CP2b. Finally, dramatic increment of hemoglobin expression was correlated with nuclear translocation of CP2c during MEL cell differentiation. Our data suggest that CP2b potentiate erythroid cell-specific {alpha}-globin expression by recruiting CP2c into the nucleus.

  8. Characterization of Human Disease Phenotypes Associated with Mutations in TREX1, RNASEH2A, RNASEH2B, RNASEH2C, SAMHD1, ADAR, and IFIH1

    PubMed Central

    Crow, Yanick J.; Chase, Diana S.; Schmidt, Johanna Lowenstein; Szynkiewicz, Marcin; Forte, Gabriella M.A.; Gornall, Hannah L.; Oojageer, Anthony; Anderson, Beverley; Pizzino, Amy; Helman, Guy; Abdel-Hamid, Mohamed S.; Abdel-Salam, Ghada M.; Ackroyd, Sam; Aeby, Alec; Agosta, Guillermo; Albin, Catherine; Allon-Shalev, Stavit; Arellano, Montse; Ariaudo, Giada; Aswani, Vijay; Babul-Hirji, Riyana; Baildam, Eileen M.; Bahi-Buisson, Nadia; Bailey, Kathryn M.; Barnerias, Christine; Barth, Magalie; Battini, Roberta; Beresford, Michael W.; Bernard, Geneviève; Bianchi, Marika; de Villemeur, Thierry Billette; Blair, Edward M.; Bloom, Miriam; Burlina, Alberto B.; Carpanelli, Maria Luisa; Carvalho, Daniel R.; Castro-Gago, Manuel; Cavallini, Anna; Cereda, Cristina; Chandler, Kate E.; Chitayat, David A.; Collins, Abigail E.; Corcoles, Concepcion Sierra; Cordeiro, Nuno J.V.; Crichiutti, Giovanni; Dabydeen, Lyvia; Dale, Russell C.; D’Arrigo, Stefano; De Goede, Christian G.E.L.; De Laet, Corinne; De Waele, Liesbeth M.H.; Denzler, Ines; Desguerre, Isabelle; Devriendt, Koenraad; Di Rocco, Maja; Fahey, Michael C.; Fazzi, Elisa; Ferrie, Colin D.; Figueiredo, António; Gener, Blanca; Goizet, Cyril; Gowrinathan, Nirmala R.; Gowrishankar, Kalpana; Hanrahan, Donncha; Isidor, Bertrand; Kara, Bülent; Khan, Nasaim; King, Mary D.; Kirk, Edwin P.; Kumar, Ram; Lagae, Lieven; Landrieu, Pierre; Lauffer, Heinz; Laugel, Vincent; La Piana, Roberta; Lim, Ming J.; Lin, Jean-Pierre S.-M.; Linnankivi, Tarja; Mackay, Mark T.; Marom, Daphna R.; Lourenço, Charles Marques; McKee, Shane A.; Moroni, Isabella; Morton, Jenny E.V.; Moutard, Marie-Laure; Murray, Kevin; Nabbout, Rima; Nampoothiri, Sheela; Nunez-Enamorado, Noemi; Oades, Patrick J.; Olivieri, Ivana; Ostergaard, John R.; Pérez-Dueñas, Belén; Prendiville, Julie S.; Ramesh, Venkateswaran; Rasmussen, Magnhild; Régal, Luc; Ricci, Federica; Rio, Marlène; Rodriguez, Diana; Roubertie, Agathe; Salvatici, Elisabetta; Segers, Karin A.; Sinha, Gyanranjan P.; Soler, Doriette; Spiegel, Ronen; Stödberg, Tommy I.; Straussberg, Rachel; Swoboda, Kathryn J.; Suri, Mohnish; Tacke, Uta; Tan, Tiong Y.; Naude, Johann te Water; Teik, Keng Wee; Thomas, Maya Mary; Till, Marianne; Tonduti, Davide; Valente, Enza Maria; Van Coster, Rudy Noel; van der Knaap, Marjo S.; Vassallo, Grace; Vijzelaar, Raymon; Vogt, Julie; Wallace, Geoffrey B.; Wassmer, Evangeline; Webb, Hannah J.; Whitehouse, William P.; Whitney, Robyn N.; Zaki, Maha S.; Zuberi, Sameer M.; Livingston, John H.; Rozenberg, Flore; Lebon, Pierre; Vanderver, Adeline; Orcesi, Simona; Rice, Gillian I.

    2015-01-01

    Aicardi–Goutières syndrome is an inflammatory disease occurring due to mutations in any of TREX1, RNASEH2A, RNASEH2B, RNASEH2C, SAMHD1, ADAR or IFIH1. We report on 374 patients from 299 families with mutations in these seven genes. Most patients conformed to one of two fairly stereotyped clinical profiles; either exhibiting an in utero disease-onset (74 patients; 22.8% of all patients where data were available), or a post-natal presentation, usually within the first year of life (223 patients; 68.6%), characterized by a sub-acute encephalopathy and a loss of previously acquired skills. Other clinically distinct phenotypes were also observed; particularly, bilateral striatal necrosis (13 patients; 3.6%) and non-syndromic spastic paraparesis (12 patients; 3.4%). We recorded 69 deaths (19.3% of patients with follow-up data). Of 285 patients for whom data were available, 210 (73.7%) were profoundly disabled, with no useful motor, speech and intellectual function. Chilblains, glaucoma, hypothyroidism, cardiomyopathy, intracerebral vasculitis, peripheral neuropathy, bowel inflammation and systemic lupus erythematosus were seen frequently enough to be confirmed as real associations with the Aicardi-Goutieres syndrome phenotype. We observed a robust relationship between mutations in all seven genes with increased type I interferon activity in cerebrospinal fluid and serum, and the increased expression of interferon-stimulated gene transcripts in peripheral blood. We recorded a positive correlation between the level of cerebrospinal fluid interferon activity assayed within one year of disease presentation and the degree of subsequent disability. Interferon-stimulated gene transcripts remained high in most patients, indicating an ongoing disease process. On the basis of substantial morbidity and mortality, our data highlight the urgent need to define coherent treatment strategies for the phenotypes associated with mutations in the Aicardi–Goutières syndrome

  9. Co-Circulation of the Rare CPV-2c with Unique Gln370Arg Substitution, New CPV-2b with Unique Thr440Ala Substitution, and New CPV-2a with High Prevalence and Variation in Heilongjiang Province, Northeast China

    PubMed Central

    Geng, Yufei; Guo, Donghua; Li, Chunqiu; Wang, Enyu; Wei, Shan; Wang, Zhihui; Yao, Shuang; Zhao, Xiwen; Su, Mingjun; Wang, Xinyu; Wang, Jianfa; Wu, Rui; Feng, Li; Sun, Dongbo

    2015-01-01

    To trace evolution of canine parvovirus-2 (CPV-2), a total of 201 stool samples were collected from dogs with diarrhea in Heilongjiang province of northeast China from May 2014 to April 2015. The presence of CPV-2 in the samples was determined by PCR amplification of the VP2 gene (568 bp) of CPV-2. The results revealed that 95 samples (47.26%) were positive for CPV-2, and they showed 98.8%–100% nucleotide identity and 97.6%–100% amino acid identity. Of 95 CPV-2-positive samples, types new2a (Ser297Ala), new2b (Ser297Ala), and 2c accounted for 64.21%, 21.05%, and 14.74%, respectively. The positive rate of CPV-2 and the distribution of the new2a, new2b and 2c types exhibited differences among regions, seasons, and ages. Immunized dogs accounted for 48.42% of 95 CPV-2-positive samples. Coinfections with canine coronavirus, canine kobuvirus, and canine bocavirus were identified. Phylogenetic analysis revealed that the identified new2a, new2b, and CPV-2c strains in our study exhibited a close relationship with most of the CPV-2 strains from China; type new2a strains exhibited high variability, forming three subgroups; type new2b and CPV-2c strains formed one group with reference strains from China. Of 95 CPV-2 strains, Tyr324Ile and Thr440Ala substitutions accounted for 100% and 64.21%, respectively; all type new2b strains exhibited the Thr440Ala substitution, while the unique Gln370Arg substitution was found in all type 2c strains. Recombination analysis using entire VP2 gene indicated possible recombination events between the identified CPV-2 strains and reference strains from China. Our data revealed the co-circulation of new CPV-2a, new CPV-2b, and rare CPV-2c, as well as potential recombination events among Chinese CPV-2 strains. PMID:26348721

  10. Aquifer-test data for wells H-1, H-2A, H-2B, H-2C, and H-3 at the Waste Isolation Pilot Plant, southeastern New Mexico

    USGS Publications Warehouse

    Huff, G.F.; Gregory, Angela

    2006-01-01

    A series of aquifer tests was performed by the U.S. Geological Survey on geologic units of Permian age at the Waste Isolation Pilot Plant site between February 1979 and July 1980 in wells H-1, H-2 complex (H-2A, H-2B, and H-2C), and H-3. The tested geologic units included the Magenta Dolomite and Culebra Dolomite Members of the Rustler Formation, and the contact zone between the Rustler and Salado Formations. Selected information on the tested formations, test dates, pre-test static water levels, test configurations, and raw data collected during these tests are tabulated in this report.

  11. A Novel Aminotetralin-Type Serotonin (5-HT) 2C Receptor-Specific Agonist and 5-HT2A Competitive Antagonist/5-HT2B Inverse Agonist with Preclinical Efficacy for Psychoses

    PubMed Central

    Morgan, Drake; Felsing, Daniel; Kondabolu, Krishnakanth; Rowland, Neil E.; Robertson, Kimberly L.; Sakhuja, Rajeev; Booth, Raymond G.

    2014-01-01

    Development of 5-HT2C agonists for treatment of neuropsychiatric disorders, including psychoses, substance abuse, and obesity, has been fraught with difficulties, because the vast majority of reported 5-HT2C selective agonists also activate 5-HT2A and/or 5-HT2B receptors, potentially causing hallucinations and/or cardiac valvulopathy. Herein is described a novel, potent, and efficacious human 5-HT2C receptor agonist, (−)-trans-(2S,4R)-4-(3′[meta]-bromophenyl)-N,N-dimethyl-1,2,3,4-tetrahydronaphthalen-2-amine (−)-MBP), that is a competitive antagonist and inverse agonist at human 5-HT2A and 5-HT2B receptors, respectively. (−)-MBP has efficacy comparable to the prototypical second-generation antipsychotic drug clozapine in three C57Bl/6 mouse models of drug-induced psychoses: the head-twitch response elicited by [2,5]-dimethoxy-4-iodoamphetamine; hyperlocomotion induced by MK-801 [(5R,10S)-(+)-5-methyl-10,11-dihydro-5H-dibenzo[a,d]cyclohepten-5,10-imine hydrogen maleate (dizocilpine maleate)]; and hyperlocomotion induced by amphetamine. (−)-MBP, however, does not alter locomotion when administered alone, distinguishing it from clozapine, which suppresses locomotion. Finally, consumption of highly palatable food by mice was not increased by (−)-MBP at a dose that produced at least 50% maximal efficacy in the psychoses models. Compared with (−)-MBP, the enantiomer (+)-MBP was much less active across in vitro affinity and functional assays using mouse and human receptors and also translated in vivo with comparably lower potency and efficacy. Results indicate a 5-HT2C receptor-specific agonist, such as (−)-MBP, may be pharmacotherapeutic for psychoses, without liability for obesity, hallucinations, heart disease, sedation, or motoric disorders. PMID:24563531

  12. Review of magnetic features observed in (A,A')Ni 2B 2C solid solutions

    NASA Astrophysics Data System (ADS)

    Kuznietz, Moshe; Gonçalves, António P.; Almeida, Manuel

    2002-08-01

    The nickel-borocarbides ANi 2B 2C [A=Y, Ln (lanthanide), An(actinide)], crystallizing in the body-centred tetragonal LuNi 2B 2C-type structure, are classified according to the existence or coexistence of superconducting and antiferromagnetic states (AF). The magnetic features observed in polycrystalline (A,A')Ni 2B 2C solid solutions, adopting the same crystal structure, are reviewed and discussed. Published data on the magnetism in (A,Ln)Ni 2B 2C systems (ANi 2B 2C nonmagnetic, A=Y,La,Lu) indicate a gradual rise in the threshold content, x( m), in (Y 1- xLn x)Ni 2B 2C (Ln=Gd,Tb,Dy,Ho,Er) for the establishment of AF states. (A,A')Ni 2B 2C systems with magnetic end compounds show gradual variation in magnetic features when A and A' are both heavy Ln. The behaviour of (A,A')Ni 2B 2C systems of light A (Pr or U) and heavy A' (Dy or Tm) depends on the magnetic structures of the end compounds. In intermediate compositions, incomplete moment compensation in (Pr,Dy)Ni 2B 2C decreases TN, while different moment directions in the end compounds in (U,Dy)Ni 2B 2C lead to a directional frustration of ordered moments. Such a frustration in (U,Tm)Ni 2B 2C is related to different magnetic structures of the end compounds.

  13. Transport Anisotropy in ErNi2B2C Along c-AXIS

    NASA Astrophysics Data System (ADS)

    Lee, W. C.

    The resistivities along c-axis ρc(H, T) of ErNi2 B2C have been measured with H⊥ and H‖ c-axis for 2 < T < 300 K and the superconducting upper critical field Hc2(T) curves of ErNi2B2C were constructed for each magnetic fields. Our Hc2(T) curves have been compared and discussed with those from ρab(H, T) measurements which explain the anisotropy and its temperature dependence of Hc2(T) are thought to arise from magnetic pair breaking and the anisotropic field dependence of Néel temperature TN originated from Er+3 sublattice.

  14. Anomalous behavior of PrNi{sub 2}B{sub 2}C borocarbide

    SciTech Connect

    Narozhnyi, V.N.; Freudenberger, J.; Fuchs, G.; Nenkov, K.A.; Eckert, D.; Czopnik, A.; Mueller, K.H.

    1999-12-01

    Electrical resistivity {rho}(T), specific heat C{sub p}(T), magnetic susceptibility {chi}(T), and magnetization M(H) have been measured for polycrystalline PrNi{sub 2}B{sub 2}C. Maxima in C{sub p}(T) and {vert{underscore}bar}d{chi}(T)/dT{vert{underscore}bar} dependencies were found at T{sub N} {approx} 4.3 K connected with AFM ordering observed earlier by neutron diffraction. The Sommerfeld coefficient is at least 250 mJ/mol K{sup 2}. The values of T{sub N} for PrNi{sub 2}B{sub 2}C and {vert{underscore}bar}d{Tc}/dx{vert{underscore}bar} for Y{sub 1{minus}x}Pr{sub x}Ni{sub 2}B{sub 2}C were found to be much larger than estimated by the de Gennes scaling from the Gd-based borocarbides. These facts as well as anomalous decrease of {rho}(T) found below 20K are connected with moderate heavy fermion behavior of antiferromagnetic PrNi{sub 2}B{sub 2}C.

  15. Magnetic structures in RNi{sub 2}B{sub 2}C (R = Ho, Er) superconductors

    SciTech Connect

    Stassis, C.; Goldman, A.I.; Dervenagas, P.; Zarestky, J.; Canfield, P.C.; Cho, B.K.; Johnston, D.C.; Sternlieb, B.; Sternlieb, B.

    1994-12-31

    Single crystal neutron diffraction techniques have been employed to study the evolution of magnetic structures in RNi{sub 2}B{sub 2}C compounds in an attempt to understand the relationship between magnetic ordering and superconductivity in several members of this series. For HoNi{sub 2}B{sub 2}C, below the superconducting transition (T{sub c} = 8 K), an incommensurate magnetic structure characterized by two wave vectors (0.585 a* and 0.915 c*) is found in a narrow temperature range between 4.7 K and 6 K. This is the same temperature range where bulk measurements find a deep minimum in the upper critical field, H{sub c2}. Below 4.7 K, HoNi{sub 2}B{sub 2}C is a simple collinear antiferromagnet. ErNi{sub 2}B{sub 2}C ({Tc} = 11 K) orders in an incommensurate modulated antiferromagnetic state characterized by an ordering wave vector 0.553 a* below 7 K, which coexists with superconductivity.

  16. Quadrupolar interaction of ^57Fe in compounds RENi_2B_2C: Experimental and Theoretical Studies

    NASA Astrophysics Data System (ADS)

    Zeng, Zhi; Guenzburger, Diana; Sanchez, D. R. S.; Bud'Ko, S. L.; Fontes, Magda B.; Baggia-Saitovitch, E. M.; Ellis, D. E.

    1996-03-01

    ^57Fe Mössbauer spectra were taken with the RE(Ni_0.99^57Fe_0.01)_2B_2C (RE=Tb, Dy, Ho, Er) samples in a variable temperature helium crysostat to study the interplay between superconductivity and magnetism in the RENi_2B_2C (RE=Dy, Ho, Er, Tm) compounds. The rare earth dependent quadrupole splitting (QS) from ^57Fe Mössbauer spectra decreases with the lanthanide contraction^footnotetext^The lanthanide contraction causes an increase in the ratio c/a along the RE series. from QS=0.27mm/s for TbNi_2B_2C to QS=0.14mm/s for ErNi_2B_2C. Self-consistent frist-principles electronic structure calculation[1] were performed for clusters with 71 atoms (Fe-12RE-14Ni-32B-12C), which were embedded in the charge denisity of several shells of neighbours in the crystal, representing the doped compounds RE(Ni_0.93Fe_0.07)_2B_2C (RE=Gd, Tb, Dy, Ho, and Er). The quadrupole splitting was obtained with the nuclear quadrupole moment Q=0.16b of ^57Fe[2]. The calculated results are in good agreement with experiment. The theoretical results give negative signs for all the QS values; which have not been determined by experiment, except for the compounds with Tb and Ho, for which they are negative. REFERENCES D.E. Ellis, Int. J. Quant. Chem. Suppl. 2, 35(1968); D.E. Ellis and G.S. Painter, Phys. Rev. B, 2, 2887(1970). Ohilipp Dufek, Peter Blaha and K. Schwarz, Phys. Rev. Lett. 75, 3545(1995).

  17. Angular-dependent I-V characteristics in borocarbide superconductor YNi(2)B(2)C.

    PubMed

    Chu, R M; Chen, Q Y; Chu, W K

    2006-04-26

    We present angular-dependent current-voltage (I-V) measurements in borocarbide YNi(2)B(2)C single crystals near the vortex-glass irreversible line. External magnetic fields are applied along the angle θ with respect to the c-axis. The nonlinear I-V curves reveal scaling behaviour near the transition. Using the scaling analysis, the relevant critical exponents and vortex transition temperatures are determined for all orientations. The data agrees well with the vortex-glass (VG) model. No evidence was found that supports the existence of a Bose-glass (BG) type of transition.

  18. Vortex imaging of magnetic superconductor HoNi 2B 2C by scanning SQUID microscopy

    NASA Astrophysics Data System (ADS)

    Hata, Y.; Suzuki, J.; Kakeya, I.; Kadowaki, K.; Nakayama, S.; Nagata, A.; Odawara, A.; Chinone, K.

    2002-10-01

    We have observed vortex trapped images in the ab-plane of a HoNi 2B 2C single crystal in a magnetic field of 1.2 μT at 4 K using a scanning SQUID microscope. The vortex observed has a fine structure consisting of two regions with opposite signs of the magnetic field which is quantized with multiple flux quanta as a whole. The spatial size of the magnetic field distribution extends over 10 μm. Such giant vortices are also observed at TN< T< TC and disappear above TC where TN is the magnetic transition temperature and TC is the superconducting transition temperature.

  19. Vortex lattice structures in YNi{sub 2}B{sub 2}C

    SciTech Connect

    Yethiraj, M.; Paul, D.M.; Tomy, C.V.; Forgan, E.M.

    1997-12-01

    The authors observe a flux lattice with square symmetry in the superconductor YNi{sub 2}B{sub 2}C when the applied field is parallel to the c-axis of the crystal. A square lattice observed previously in the isostructural magnetic analog ErNi{sub 2}B{sub 2}C was attributed to the interaction between magnetic order in that system and the flux lattice. Since the Y-based compound does not order magnetically, it is clear that the structure of the flux lattice is unrelated to magnetic order. In fact, they show that the flux lines have a square cross-section when the applied field is parallel to the c-axis of the crystal, since the measured penetration depth along the 100 crystal direction is larger than the penetration depth along the 110 by approximately 60%. This is the likely reason for the square symmetry of the lattice. Although they find considerable disorder in the arrangement of the flux lines at 2.5T, no melting of the vortex lattice was observed.

  20. Rf2a and rf2b transcription factors

    DOEpatents

    Beachy, Roger N.; Petruccelli, Silvana; Dai, Shunhong

    2007-10-02

    A method of activating the rice tungro bacilliform virus (RTBV) promoter in vivo is disclosed. The RTBV promoter is activated by exposure to at least one protein selected from the group consisting of Rf2a and Rf2b.

  1. Synthesis and characterization of new quaternary borocarbides RRh{sub 2}B{sub 2}C (R = rare earth)

    SciTech Connect

    Ye, Jinhua; Matsumoto, Takehiko; Shishido, Toetsu

    1997-10-01

    Arc-melting syntheses of RRh{sub 2}B{sub 2}C were carried out for all lanthanide elements except promethium. X ray diffraction revealed that new compounds exit for R = Y, La-Er (except Eu), and the stability of RRh{sub 2}B{sub 2}C decreases for the smaller lanthanide. The tetragonal a-axis of RRh{sub 2}B{sub 2}C decreases for the smaller lanthanide. The tetragonal a-axis of RRh{sub 2}B{sub 2}C was found to contract as R goes from La to Er. The c-axis, however, expands slightly. In accordance with the lattice parameter change, interatomic distances between Rh atoms decrease significantly from 2.7623 {angstrom} in LaRh{sub 2}B{sub 2}C to 2.6552 {angstrom} in ErRh{sub 2}B{sub 2}C. The reduced stability of the RRh{sub 2}B{sub 2}C phase for the smaller rare earth is explained by the change in the crystallographic parameters with the size of R.

  2. Scanning Hall Probe Imaging of ErNi2B2C

    SciTech Connect

    Bluhm, Hendrik; Sebastian, Suchitra; Guikema, Janice W.; Fisher, I.R.; Moler, Kathryn A.; /Stanford U., Appl. Phys. Dept.

    2005-12-02

    We report scanning Hall probe imaging of ErNi{sub 2}B{sub 2}C in the superconducting, antiferromagnetic, and weakly ferromagnetic regimes in magnetic fields up to 20 Oe, well below H{sub c1}, with two results. First, imaging isolated vortices shows that they spontaneously rearrange on cooling through the antiferromagnetic transition temperature T{sub N} = 6 K to pin on twin boundaries, forming a striped pattern. Second, a weak, random magnetic signal appears in the ferromagnetic phase below T{sub WFM} = 2.3 K, and no spontaneous vortex lattice is present down to 1.9 K. We conclude that ferromagnetism coexists with superconductivity either by forming small ferromagnetic domains or with oscillatory variation of the magnetization on sub-penetration depth length scales.

  3. Electronic Commerce in Tourism in China: B2B or B2C?

    NASA Astrophysics Data System (ADS)

    Li, Hongxiu; Suomi, Reima

    E-commerce has significantly changed the distribution channels of travel products in the world including China. Online channels are growing important in travel service distribution. In China tourism industry has been developed rapidly with the economic development, more and more international travel service providers are trying to expand their Chinese market through the Internet. This paper sheds lights on the e-commerce development models in China for international travel service providers. It explores the current e-tourism in China from the three different participants in the value chain in tourism industry - consumer, travel agent and travel service provider. The paper also identifies the barriers in B2C arena in international outbound travel market, and discusses the possible approaches for international travel service providers to develop their e-commerce in the huge Chinese market. The results in this study reveal that international travel service providers should focus on B2B model to expand their electronic market in China. B2C development in tourism largely depends on the change of Chinese customers' behavior and the change of international tourism regulations. The findings of the study are expected to assist international travel service providers to understand current e-tourism in China and to support their planning for future e-commerce development in China.

  4. Complex Structures in the Reentrant Phase Diagram of HoNi_2B_2C

    NASA Astrophysics Data System (ADS)

    Childers, J.; Zhang, J.; Olinger, A., Jr.; Metlushko, V.; Delong, L.; Canfield, P.

    1996-03-01

    HoNi_2B_2C exhibits a resistive onset to superconductivity near 9.0 K, followed by transitions to incommensurate magnetic order (IMO) at 6.0 K and 5.5 K, and commensurate antiferromagnetic order (AFM) at TN = 5.2 K. Vibrating reed (VR) and resistance data reveal two previously unobserved lines of magnetic anomalies in both the upper superconducting (SC) and lower reentrant SC regions for H || a*b*. The wide region between the upper onset of SC and the first magnetic anomaly reflects weak vortex pinning, possibly due to a subtle buildup of IMO from well above 8K. The interplay between SC and magnetic order is evident in abrupt displacements of transition lines to IMO near their crossing with the reentrant normal transition line for 5.2

  5. We Need 2C but Not 2B: Developing Serotonin 2C (5-HT2C) Receptor Agonists for the Treatment of CNS Disorders

    PubMed Central

    Cheng, Jianjun; Kozikowski, Alan P.

    2016-01-01

    The serotonin 2C (5-HT2C) receptor has been identified as a potential drug target for the treatment of a variety of central nervous system (CNS) disorders, such as obesity, substance abuse, and schizophrenia. In this Viewpoint article, recent progress in developing selective 5-HT2C agonists for use in treating these disorders is summarized, including the work of our group. Challenges in this field and the possible future directions are described. Homology modeling as a method to predict the binding modes of 5-HT2C ligands to the receptor is also discussed. Compared to known ligands, the improved pharmacological profiles of the 2-phenylcyclopropylmethylamine-based 5-HT2C agonists make them preferred candidates for further studies. PMID:26507582

  6. Transport and superconducting properties of RNi2B2C (R=Y,nLu) single crystals

    NASA Astrophysics Data System (ADS)

    Rathnayaka, K. D. D.; Bhatnagar, A. K.; Parasiris, A.; Naugle, D. G.; Canfield, P. C.; Cho, B. K.

    1997-04-01

    The in-plane resistivity, in-plane absolute thermopower, and upper critical field measurements are reported for single-crystal samples of YNi2B2C and LuNi2B2C superconductors. The in-plane resistivity shows metallic behavior and varies approximately linearly with temperature near room temperature (RT) but shows nearly quadratic behavior in temperature at low temperatures. The YNi2B2C and LuNi2B2C single-crystal samples exhibit large transverse magnetoresistance (~6-8 % at 45 kOe) in the ab plane. The absolute thermopower S(T) is negative from RT to the superconducting transition temperature Tc. Its magnitude at RT is a few times of the value for a typical good metal. S(T) is approximately linear in temperature between ~150 K and RT. Extrapolation to T=0 gives large intercepts (few μV/K) for both samples suggesting the presence of a much larger 'knee' than would be expected from electron-phonon interaction renormalization effects. The upper critical fields for H parallel and perpendicular to the c axis and the superconducting parameters derived from it do not show any anisotropy for the YNi2B2C single-crystal samples in agreement with magnetization and torque magnetometry measurements, but a small anisotropy is observed for the LuNi2B2C single crystals. The analysis shows that these are moderately strong-coupling type-II superconductors (similar to the A-15 compounds) with a value of the electron-phonon coupling parameter λ(0) approximately equal to 1.2 for YNi2B2C and 1.0 for LuNi2B2C, the Ginzburg-Landau coherence length ξ(0) approximately equal to 70 Å, and Hc2(0)~60-70 kOe. The temperature dependence of the upper critical field shows a positive curvature near Tc in disagreement with the Werthamer, Helfand, Hohenberg, and Maki (WHHM) theory but in agreement with a recent solution of the Gor'kov equation using a basis formed by Landau levels (Bahcall); however, the data show a severe disagreement between the observed low-temperature behavior of Hc2(T) and that

  7. Direct evidence for the electronic phase inhomogeneity in HoNi 2B 2C

    NASA Astrophysics Data System (ADS)

    Chechersky, Vladimir; Nath, Amar; Cava, R. J.

    1998-07-01

    We substitute a few parts per million of 57Co for Ni. The Mössbauer spectra of HoNi2( 57Co) B2C reveal the presence of two components, one of which is truly metallic as indicated by delocalization of 3d electrons. In the other component, the electrons are delocalized to a lesser extent. The relative ratio of the components can vary from sample to sample.

  8. Spatially resolved penetration depth measurements and vortex manipulation in the ferromagnetic superconductor ErNi2B2C

    DOE PAGES

    Wulferding, Dirk; Yang, Ilkyu; Yang, Jinho; Lee, Minkyung; Choi, Hee Cheul; Bud'ko, Sergey L.; Canfield, Paul C.; Yeom, Han Woong; Kim, Jeehoon

    2015-07-31

    We present a local probe study of the magnetic superconductor ErNi2B2C, using magnetic force microscopy at sub-Kelvin temperatures. ErNi2B2C is an ideal system to explore the effects of concomitant superconductivity and ferromagnetism. At 500 mK, far below the transition to a weakly ferromagnetic state, we directly observe a structured magnetic background on the micrometer scale. We determine spatially resolved absolute values of the magnetic penetration depth λ and study its temperature dependence as the system undergoes magnetic phase transitions from paramagnetic to antiferromagnetic, and to weak ferromagnetic, all within the superconducting regime. We estimate the absolute pinning force of Abrikosovmore » vortices, which shows a position dependence and temperature dependence as well, and discuss the possibility of the purported spontaneous vortex formation.« less

  9. Superconducting and normal state magnetic properties of RNi{sub 2}B{sub 2}C single crystals

    SciTech Connect

    Johnston, D.C.; Borsa, F.; Cho, B.K. |

    1995-10-01

    The authors` studies of the magnetic properties of RNi{sub 2}B{sub 2}C single crystals (R = Y, Gd-Tm, Lu) are reviewed. Of particular interest are the ordered magnetic structures when R is a magnetic rare earth atom, the interaction between magnetism and superconductivity, the influence of crystalline electric fields of the magnetic rare earth ions on these behaviors, and the magnetic character of the Ni sublattice.

  10. Single crystal neutron diffraction study of the magnetic structure of TmNi{sub 2}B{sub 2}C

    SciTech Connect

    Sternlieb, B.; Shapiro, S.; Stassis, C.; Goldman, A.I.; Canfield, P.

    1997-02-01

    Neutron diffraction techniques have been used to study the magnetic structure of single crystals of the magnetic superconductor (T{sub c} {congruent} 11K) TmNi{sub 2}B{sub 2}C. We find that below approximately 1.5K the magnetic moments order in an incommensurate spin wave with propagation vector q{sub m} = q{sub m} (a* +b*) (or q{sub m} = q{sub m} (a* + b*)) with q{sub m} = 0.094 {+-} 0.001. The spin wave is transverse with the moments aligned along the c-axis, and the observation of relatively intense higher order harmonics shows that the modulation is not purely sinusoidal but considerably squared. This incommensurate magnetic structure, which coexists with superconductivity below T{sub N} {congruent} 1.5K, is quite different from those observed in the magnetic superconductors HoNi{sub 2}B{sub 2}C and ErNi{sub 2}B{sub 2}C. The origin of diffraction peaks observed in scans parallel to a* is briefly discussed.

  11. Click Dehydrogenation of Carbon-Substituted nido-5,6-C2B8H12 Carboranes: A General Route to closo-1,2-C2B8H10 Derivatives.

    PubMed

    Tok, Oleg L; Bakardjiev, Mario; Štíbr, Bohumil; Hnyk, Drahomír; Holub, Josef; Padělková, Zdenka; Růžička, Aleš

    2016-09-01

    Triethylamine-catalyzed dehydrogenation of carbon-disubstituted dicarbaboranes 5,6-R2-nido-5,6-C2B8H10 [1, where R = H (1a), Me (1b), and Ph (1c)] in refluxing acetonitrile leads to a high-yield (up to 85-95%) formation of a series of dicarbaboranes 1,2-R2-closo-1,2-C2B8H8 (2). The monosubstituted 6-R-nido-5,6-C2B8H11 (3) analogues [where R = Ph (3a), naph (1-naphthyl; 3b), Bu (3c)] afforded 1-R-1,2-closo C2B8H9 (4) isomers [where R = Ph (4a), naph (4b), n-Bu (4c)] as the main products; compounds 4a and 4c were accompanied by 2-R-1,2-C2B8H9 (5) isomers (total yields up to 90%), with the 4/5 molar ratio being strongly dependent on the nature of R (4:1 and 1:1, respectively). All of these cage-closure reactions are supposed to proceed via the stage of the corresponding Et3NH(+) salts of nido anions [5,6-R2-5,6-C2B8H9](-) (1(-)) and [6-R-5,6-C2B8H10](-) (3(-)), which lose H2 and Et3N upon heating (dehydrodeamination). The cage-closure mechanisms leading to closo isomers 2, 4, and 5 have been substantiated by B3LYP/6-31+G* calculations of the reaction profile for a simple 1a(-) → 2a + H(-) conversion. All of the compounds isolated have been characterized by multinuclear ((11)B, (1)H, and (13)C) NMR spectroscopy, mass spectrometry, and elemental analyses, and the structure of 1-Ph-closo-1,2-C2B8H9 (4a) was established by an X-ray diffraction study. PMID:27551885

  12. Rare earth magnetic order in RNi{sub 2}B{sub 2}C and RNiBC

    SciTech Connect

    Skanthakumar, S.; Lynn, J.W.

    1998-07-05

    A review of neutron diffraction experiments on the magnetic order in the RNi{sub 2}B{sub 2}C and RNiBC (R-rare earth) systems is given. The RNi{sub 2}B{sub 2}C materials exhibit a wide variety of commensurate and incommensurate magnetic structures for different rare earths, along with superconductivity that is coupled to the magnetism. Simple commensurate antiferromagnetic structures are observed for R = Pr (T{sub N} = 4.0 K), Nd (T{sub N} = 4.8 K), Ho (T{sub N} = 8.5 K) and Dy (T{sub N} = 4.8 K). In addition, HoNi{sub 2}B{sub 2}C exhibits a c-axis spiral and an a-axis modulated incommensurate structure above 5 K, while both structures collapse in favor of the commensurate structure at low T. A transversely polarized spin density wave (SDW) type incommensurate structure is observed for Er (T{sub N} = 6.8 K) and Tm (T{sub N} = 1.5 K), while a longitudinally polarized SDW structure is observed for Tb (T{sub N} = 15 K). No magnetic ordering of any type is detected for Y, Ce and Yb. HoNiBC is an antiferromagnet (T{sub N} = 9.8 K), ErNiBC is a ferromagnetic (T{sub C} = 4.6 K), while TbNiBC and DyNiBC exhibit both ferromagnetic and antiferromagnetic ordering at 17 K and {approximately} 13 K, respectively.

  13. Experiences and Future Expectations towards Online Courses--An Empirical Study of the B2C-and B2B-Segments

    ERIC Educational Resources Information Center

    Krämer, Andreas; Böhrs, Sandra

    2016-01-01

    This article explores the future potential for the development of online courses. The findings are based on an empirical study with 3 sample groups: (1) B2C segment in Germany, (2) B2C segment in the United States, and (3) B2B segment (international). In the first step the status quo of the use of e-learning in general and online courses in…

  14. Solution structure of the isolated histone H2A-H2B heterodimer.

    PubMed

    Moriwaki, Yoshihito; Yamane, Tsutomu; Ohtomo, Hideaki; Ikeguchi, Mitsunori; Kurita, Jun-Ichi; Sato, Masahiko; Nagadoi, Aritaka; Shimojo, Hideaki; Nishimura, Yoshifumi

    2016-01-01

    During chromatin-regulated processes, the histone H2A-H2B heterodimer functions dynamically in and out of the nucleosome. Although detailed crystal structures of nucleosomes have been established, that of the isolated full-length H2A-H2B heterodimer has remained elusive. Here, we have determined the solution structure of human H2A-H2B by NMR coupled with CS-Rosetta. H2A and H2B each contain a histone fold, comprising four α-helices and two β-strands (α1-β1-α2-β2-α3-αC), together with the long disordered N- and C-terminal H2A tails and the long N-terminal H2B tail. The N-terminal αN helix, C-terminal β3 strand, and 310 helix of H2A observed in the H2A-H2B nucleosome structure are disordered in isolated H2A-H2B. In addition, the H2A α1 and H2B αC helices are not well fixed in the heterodimer, and the H2A and H2B tails are not completely random coils. Comparison of hydrogen-deuterium exchange, fast hydrogen exchange, and {(1)H}-(15)N hetero-nuclear NOE data with the CS-Rosetta structure indicates that there is some conformation in the H2A 310 helical and H2B Lys11 regions, while the repression domain of H2B (residues 27-34) exhibits an extended string-like structure. This first structure of the isolated H2A-H2B heterodimer provides insight into its dynamic functions in chromatin. PMID:27181506

  15. Solution structure of the isolated histone H2A-H2B heterodimer

    PubMed Central

    Moriwaki, Yoshihito; Yamane, Tsutomu; Ohtomo, Hideaki; Ikeguchi, Mitsunori; Kurita, Jun-ichi; Sato, Masahiko; Nagadoi, Aritaka; Shimojo, Hideaki; Nishimura, Yoshifumi

    2016-01-01

    During chromatin-regulated processes, the histone H2A-H2B heterodimer functions dynamically in and out of the nucleosome. Although detailed crystal structures of nucleosomes have been established, that of the isolated full-length H2A-H2B heterodimer has remained elusive. Here, we have determined the solution structure of human H2A-H2B by NMR coupled with CS-Rosetta. H2A and H2B each contain a histone fold, comprising four α-helices and two β-strands (α1–β1–α2–β2–α3–αC), together with the long disordered N- and C-terminal H2A tails and the long N-terminal H2B tail. The N-terminal αN helix, C-terminal β3 strand, and 310 helix of H2A observed in the H2A-H2B nucleosome structure are disordered in isolated H2A-H2B. In addition, the H2A α1 and H2B αC helices are not well fixed in the heterodimer, and the H2A and H2B tails are not completely random coils. Comparison of hydrogen-deuterium exchange, fast hydrogen exchange, and {1H}-15N hetero-nuclear NOE data with the CS-Rosetta structure indicates that there is some conformation in the H2A 310 helical and H2B Lys11 regions, while the repression domain of H2B (residues 27–34) exhibits an extended string-like structure. This first structure of the isolated H2A-H2B heterodimer provides insight into its dynamic functions in chromatin. PMID:27181506

  16. Serotonin increases ERK1/2 phosphorylation in astrocytes by stimulation of 5-HT2B and 5-HT2C receptors.

    PubMed

    Li, Baoman; Zhang, Shiquen; Li, Min; Hertz, Leif; Peng, Liang

    2010-11-01

    We have previously shown that fluoxetine causes ERK(1/2) phosphorylation in cultured mouse astrocytes mediated exclusively by stimulation of 5-HT(2B) receptors (Li et al., 2008b). This raises the question whether this is also the case for serotonin (5-HT) itself. In the present study serotonin was found to induce ERK(1/2) phosphorylation by stimulation of 5-HT(2B) receptors with high affinity (EC(50): 20-30 pM), and by stimulation of 5-HT(2C) receptor with low affinity (EC(50): 1 microM or higher). ERK(1/2) phosphorylation induced by stimulation of either 5-HT(2B) or 5-HT(2C) receptors was mediated by epidermal growth factor (EGF) receptor transactivation (Peng et al., this issue), shown by the inhibitory effect of AG1478, an inhibitor of the EGF receptor tyrosine kinase, and GM6001, an inhibitor of Zn-dependent metalloproteinases, and thus of 5-HT(2B) receptor-mediated EGF receptor agonist release. It is discussed that the high potency of the 5-HT(2B)-mediated effect is consistent with literature data for binding affinity of serotonin to cloned human 5-HT(2B) receptors and with observations of low extracellular concentrations of serotonin in brain, which would allow a demonstrated moderate and modality-dependent increase in specific brain areas to activate 5-HT(2B) receptors. In contrast the relevance of the observed 5-HT(2C) receptors on astrocytes is questioned.

  17. Fabrication Report for the AFC-2A and AFC-2B Capsule Irradiations in the ATR

    SciTech Connect

    Timothy A. Hyde

    2007-10-01

    This document provides a general narrative description of the AFC-2A and 2B fuel fabrication processes for the AFC 2A and AFC 2B fuel irradiation experiments fabricated at the Idaho National Laboratory’s Materials and Fuels Complex (MFC) for irradiation in the Advanced Test Reactor (ATR).

  18. Pathogenesis of PCV2a and PCV2b virus in germ-free pigs

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Genetic analysis of porcine circovirus type 2 (PCV2) reveals 2 subgroups that will be referred to as PCV2a and PCV2b representing the North American and European prototypes respectfully. This paper summarizes 3 studies comparing the pathogenesis of 2a and 2b viruses in germ-free pigs. In this PCV2...

  19. NMDA receptor surface mobility depends on NR2A-2B subunits

    PubMed Central

    Groc, Laurent; Heine, Martin; Cousins, Sarah L.; Stephenson, F. Anne; Lounis, Brahim; Cognet, Laurent; Choquet, Daniel

    2006-01-01

    The NR2 subunit composition of NMDA receptors (NMDARs) varies during development, and this change is important in NMDAR-dependent signaling. In particular, synaptic NMDAR switch from containing mostly NR2B subunit to a mixture of NR2B and NR2A subunits. The pathways by which neurons differentially traffic NR2A- and NR2B-containing NMDARs are poorly understood. Using single-particle and -molecule approaches and specific antibodies directed against NR2A and NR2B extracellular epitopes, we investigated the surface mobility of native NR2A and NR2B subunits at the surface of cultured neurons. The surface mobility of NMDARs depends on the NR2 subunit subtype, with NR2A-containing NMDARs being more stable than NR2B-containing ones, and NR2A subunit overexpression stabilizes surface NR2B-containing NMDARs. The developmental change in the synaptic surface content of NR2A and NR2B subunits was correlated with a developmental change in the time spent by the subunits within synapses. This suggests that the switch in synaptic NMDAR subtypes depends on the regulation of the receptor surface trafficking. PMID:17124177

  20. Acid-Sensing Ion Channel 2a (ASIC2a) Promotes Surface Trafficking of ASIC2b via Heteromeric Assembly

    PubMed Central

    Kweon, Hae-Jin; Kim, Dong-Il; Bae, Yeonju; Park, Jae-Yong; Suh, Byung-Chang

    2016-01-01

    Acid-sensing ion channels (ASICs) are proton-activated cation channels that play important roles as typical proton sensors during pathophysiological conditions and normal synaptic activities. Among the ASIC subunits, ASIC2a and ASIC2b are alternative splicing products from the same gene, ACCN1. It has been shown that ASIC2 isoforms have differential subcellular distribution: ASIC2a targets the cell surface by itself, while ASIC2b resides in the ER. However, the underlying mechanism for this differential subcellular localization remained to be further elucidated. By constructing ASIC2 chimeras, we found that the first transmembrane (TM1) domain and the proximal post-TM1 domain (17 amino acids) of ASIC2a are critical for membrane targeting of the proteins. We also observed that replacement of corresponding residues in ASIC2b by those of ASIC2a conferred proton-sensitivity as well as surface expression to ASIC2b. We finally confirmed that ASIC2b is delivered to the cell surface from the ER by forming heteromers with ASIC2a, and that the N-terminal region of ASIC2a is additionally required for the ASIC2a-dependent membrane targeting of ASIC2b. Together, our study supports an important role of ASIC2a in membrane targeting of ASIC2b. PMID:27477936

  1. The interplay between magnetism and superconductivity in RNi 2B 2C (R dbnd Lu, Tm, Er, Ho, Dy, Tb, Gd)

    NASA Astrophysics Data System (ADS)

    El Massalami, M.; Bud'ko, S. L.; Giordanengo, B.; Baggio-Saitovitch, E. M.

    1995-02-01

    The superconducting and magnetic phase diagram (characteristic temperatures versus effective ionic radii) of the RNi 2B 2C (R dbnd Lu, Tm, Er, Ho, Dy, Tb, Gd) compounds are considered. Although the gradual degradation of superconductivity can be scaled to the de Gennes factor, ( g-1) 2J( J + 1), the unique reentrant behavior of the HoNi 2B 2C compound and the abrupt quenching of superconductivity for R lighter than Ho are most probably unaccountable within this scheme. Rather, it is argued that their low- T magnetic and transport properties as well as the main features of the interplay between magnetism and superconductivity can be accounted for if the low- T magnetism of HoNi 2B 2C, as reported by Grigereit et al., is generalized to the other isomorphous R members. Thus the onset of the 4f moments antiferromagnetic state at T1 is accompanied by an oscillatory component, which transforms to a commensurate antiferromagnetic state at T2. For HoNi 2B 2C, the pressure and magnetic-field influence on Tc, T1 and T2 will be discussed.

  2. Serotonin increases ERK1/2 phosphorylation in astrocytes by stimulation of 5-HT2B and 5-HT2C receptors.

    PubMed

    Li, Baoman; Zhang, Shiquen; Li, Min; Hertz, Leif; Peng, Liang

    2010-11-01

    We have previously shown that fluoxetine causes ERK(1/2) phosphorylation in cultured mouse astrocytes mediated exclusively by stimulation of 5-HT(2B) receptors (Li et al., 2008b). This raises the question whether this is also the case for serotonin (5-HT) itself. In the present study serotonin was found to induce ERK(1/2) phosphorylation by stimulation of 5-HT(2B) receptors with high affinity (EC(50): 20-30 pM), and by stimulation of 5-HT(2C) receptor with low affinity (EC(50): 1 microM or higher). ERK(1/2) phosphorylation induced by stimulation of either 5-HT(2B) or 5-HT(2C) receptors was mediated by epidermal growth factor (EGF) receptor transactivation (Peng et al., this issue), shown by the inhibitory effect of AG1478, an inhibitor of the EGF receptor tyrosine kinase, and GM6001, an inhibitor of Zn-dependent metalloproteinases, and thus of 5-HT(2B) receptor-mediated EGF receptor agonist release. It is discussed that the high potency of the 5-HT(2B)-mediated effect is consistent with literature data for binding affinity of serotonin to cloned human 5-HT(2B) receptors and with observations of low extracellular concentrations of serotonin in brain, which would allow a demonstrated moderate and modality-dependent increase in specific brain areas to activate 5-HT(2B) receptors. In contrast the relevance of the observed 5-HT(2C) receptors on astrocytes is questioned. PMID:20450948

  3. Different effects of proton pump inhibitors and famotidine on the clopidogrel metabolic activation by recombinant CYP2B6, CYP2C19 and CYP3A4.

    PubMed

    Ohbuchi, Masato; Noguchi, Kiyoshi; Kawamura, Akio; Usui, Takashi

    2012-07-01

    Inhibitory potential of proton pump inhibitors (PPIs) and famotidine, an H(2) receptor antagonist, on the metabolic activation of clopidogrel was evaluated using recombinant CYP2B6, CYP2C19 and CYP3A4. Formation of the active metabolite from an intermediate metabolite, 2-oxo-clopidogrel, was investigated by liquid chromatography-tandem mass spectrometry and three peaks corresponding to the pharmacologically active metabolite and its stereoisomers were detected. Omeprazole potently inhibited clopidogrel activation by CYP2C19 with an IC(50) of 12.8 μmol/L and more weakly inhibited that by CYP2B6 and CYP3A4. IC(50) of omeprazole for CYP2C19 and CYP3A4 was decreased about two- and three-fold, respectively, by 30-min preincubation with NADPH. Lansoprazole, esomeprazole, pantoprazole, rabeprazole and rabeprazole thioether, a major metabolite, also inhibited metabolic activation by CYP2C19, with an IC(50) of 4.3, 8.9, 48.3, 36.2 and 30.5 μmol/L, respectively. In contrast, famotidine showed no more than 20% inhibition of clopidogrel activation by CYP2B6, CYP2C19 and CYP3A4 at up to 100 μmol/L and had no time-dependent CYP2C19 and CYP3A4 inhibition. These results provide direct evidence that PPIs inhibit clopidogrel metabolic activation and suggest that CYP2C19 inhibition is the main cause of drug-drug interaction between clopidogrel and omeprazole. Famotidine is considered as a safe anti-acid agent for patients taking clopidogrel. PMID:22313038

  4. The effect of a paramagnetic metal ion within a molecule: comparison of the structurally identical paramagnetic [3,3-Fe(1,2-C2B9H11)2]- with the diamagnetic [3,3-Co(1,2-C2B9H11)2]- sandwich complexes.

    PubMed

    Cioran, Ana M; Teixidor, Francesc; Viñas, Clara

    2015-02-14

    Derivatives of the ferrabisdicarbollide [3,3'-Fe(1,2-C(2)B(9)H(11))(2)](-) have been produced starting from the zwitterion [3,3'-Fe(8-(OCH(2)CH(2))(2)-1,2-C(2)B(9)H(10))(1',2'-C(2)B(9)H(11))], 1, upon reaction with nucleophiles: alkoxides, halides and hydrosulfide ions HS(-). The result has been the preparation of [3,3'-Fe(8-(OCH(2)CH(2))(2)R/X-1,2-C(2)B(9)H(10))(1',2'-C(2)B(9)H(11))] (R = OMe, [2](-); OEt, [3](-); OCH(2)CH(2)OCH(3), [4](-); and X = Cl, [5](-); Br, [6](-); I, [7](-); and SH, [8](-)). The reaction behavior of is comparable to the well-studied cobalt equivalent, [3,3'-Co(8-(OCH(2)CH(2))2-1,2-C(2)B(9)H(10))(1',2'-C(2)B(9)H(11))], and the yields and stability of the resulting complexes are similar. These results are relevant taking into account that [3,3'-Fe(1,2-C(2)B(9)H(11))(2))(-) is a paramagnetic anion. Implications of this are observed in the (11)B-, (1)H and (13)C NMR spectra of [3,3'-Co(1,2-C(2)B(9)H(11))(2)](-) and [3,3'-Fe(1,2-C(2)B(9)H(11))(2)](-) that having identical sandwich molecular structures and the same negative charge have absolutely different widths of the NMR field, between 15 and -25 ppm for [3,3'-Co(1,2-C(2)B(9)H(11))(2)](-) and in the range 150 to -550 ppm for [3,3'-Fe(1,2-C(2)B(9)H(11))(2)](-). The sharpness of both spectra is on the other hand comparable, although no B-H couplings are observed in the Fe metallacarborane or its derivatives. Remarkable is the comparative influence vs. [3,3'-Co(1,2-C(2)B(9)H(11))(2)](-) of replacing Co by Fe on the elements of the cluster layer nearest to the metal. The two equivalent C cluster (Cc) atoms are influenced at 36 840 Hz, the two equivalent B atoms that are adjacent to the two Cc are influenced at 38 157 Hz and the single B that is adjacent to the two B atoms is influenced at 44 062 Hz. Remarkable is the similar influence on B and on C, taking into account that the values have been obtained from two distinct NMR spectra of (11)B and (13)C. The {(11)B-(11)B} COSY NMR and {(1)H

  5. Evolution of magnetic layers stacking sequence within the magnetic structure of Ho(CoxNi1-x)2B2C

    NASA Astrophysics Data System (ADS)

    ElMassalami, M.; Takeya, H.; Ouladdiaf, B.; Gomes, A. M.; Paiva, T.; dos Santos, R. R.

    2014-12-01

    We evaluated the influence of Co substitution on the magnetic structure of Ho(CoxNi1-x)2B2C (x=0.2, 0.4, 0.6, 0.8) using neutron diffraction, magnetization and specific heat studies. Different modes are stabilized: an AFM k=(0,0,1) mode for x=0.2, a spiral k=(0,0,0.49) mode for x=0.4, a spiral k=(0,0,0.26) mode for x=0.6, and a FM k=(0,0,0) mode for x=0.8. Recalling that for x=0.0, k=(0,0,1) while for x=1.0, k=(0,0,0), then all these magnetic structures can be visualized as a variation in the stacking sequence, along the z-axis, of the intra-planar FM-coupled Ho sheets as such Co substitution controls the z-component of the k=(0,0,ux) vector where ux=0,0.26,0.49, or 1. We discuss this inference and the observation that in spite of such a diversity of magnetic structures, the critical temperatures and the saturated moments are only weakly influenced by substitution.

  6. Differential expression of hoxa2a and hoxa2b genes during striped bass embryonic development.

    PubMed

    Scemama, Jean-Luc; Vernon, Jamie L; Stellwag, Edmund J

    2006-10-01

    Here, we report the cloning and expression analysis of two previously uncharacterized paralogs group 2 Hox genes, striped bass hoxa2a and hoxa2b, and the developmental regulatory gene egr2. We demonstrate that both Hox genes are expressed in the rhombomeres of the developing hindbrain and the pharyngeal arches albeit with different spatio-temporal distributions relative to one another. While both hoxa2a and hoxa2b share the r1/r2 anterior boundary of expression characteristic of the hoxa2 paralog genes of other species, hoxa2a gene expression extends throughout the hindbrain, whereas hoxa2b gene expression is restricted to the r2-r5 region. Egr2, which is used in this study as an early developmental marker of rhombomeres 3 and 5, is expressed in two distinct bands with a location and spacing typical for these two rhombomeres in other species. Within the pharyngeal arches, hoxa2a is expressed at higher levels in the second pharyngeal arch, while hoxa2b is more strongly expressed in the posterior arches. Further, hoxa2b expression within the arches becomes undetectable at 60hpf, while hoxa2a expression is maintained at least up until the beginning of chondrogenesis. Comparison of the striped bass HoxA cluster paralog group 2 (PG2) genes to their orthologs and trans-orthologs shows that the striped bass hoxa2a gene expression pattern is similar to the overall expression pattern described for the hoxa2 genes in the lobe-finned fish lineage and for the hoxa2b gene from zebrafish. It is notable that the pharyngeal arch expression pattern of the striped bass hoxa2a gene is more divergent from its sister paralog, hoxa2b, than from the zebrafish hoxa2b gene. Overall, our results suggest that differences in the Hox PG2 gene complement of striped bass and zebrafish affects both their rhombomeric and pharyngeal arch expression patterns and may account for the similarities in pharyngeal arch expression between striped bass hoxa2a and zebrafish hoxa2b.

  7. Neutron scattering studies of the RENi{sub 2}B{sub 2}C (RE = Lu, Y, Ho, Er): Lattice dynamics

    SciTech Connect

    Bullock, M.

    1998-02-23

    The first chapter gives a brief overview of the system discussed in this dissertation. Chapters 2--5 and Appendix B of this dissertation consist of papers that are published, or have been submitted, which show experimental data regarding the phonon softening of LuNi{sub 2}B{sub 2}C. These papers have been removed and processed separately. Chapter 6 will contain a summary of the conclusions up to date. Appendix A will consist of a brief derivation of {chi}(q) which is talked about in the introduction of the dissertation. Appendix B will contain a Born-von Karman model fit to the experimental LuNi{sub 2}B{sub 2}C data and a comparison with experimental data. Appendix C will contain a brief summary of the work done on LuNi{sub 2}B{sub 2}C as well as a complete listing of experimental data taken on the crystals which may be needed later for theoretical models of this system. Appendix D will outline a brief introduction covering some of the field theory used in the theoretical work for this thesis.

  8. Zebrafish Zic2a and Zic2b regulate neural crest and craniofacial development.

    PubMed

    Teslaa, Jessica J; Keller, Abigail N; Nyholm, Molly K; Grinblat, Yevgenya

    2013-08-01

    Holoprosencephaly (HPE), the most common malformation of the human forebrain, is associated with defects of the craniofacial skeleton. ZIC2, a zinc-finger transcription factor, is strongly linked to HPE and to a characteristic set of dysmorphic facial features in humans. We have previously identified important functions for zebrafish Zic2 in the developing forebrain. Here, we demonstrate that ZIC2 orthologs zic2a and zic2b also regulate the forming zebrafish craniofacial skeleton, including the jaw and neurocranial cartilages, and use the zebrafish to study Zic2-regulated processes that may contribute to the complex etiology of HPE. Using temporally controlled Zic2a overexpression, we show that the developing craniofacial cartilages are sensitive to Zic2 elevation prior to 24hpf. This window of sensitivity overlaps the critical expansion and migration of the neural crest (NC) cells, which migrate from the developing neural tube to populate vertebrate craniofacial structures. We demonstrate that zic2b influences the induction of NC at the neural plate border, while both zic2a and zic2b regulate NC migratory onset and strongly contribute to chromatophore development. Both Zic2 depletion and early ectopic Zic2 expression cause moderate, incompletely penetrant mispatterning of the NC-derived jaw precursors at 24hpf, yet by 2dpf these changes in Zic2 expression result in profoundly mispatterned chondrogenic condensations. We attribute this discrepancy to an additional role for Zic2a and Zic2b in patterning the forebrain primordium, an important signaling source during craniofacial development. This hypothesis is supported by evidence that transplanted Zic2-deficient cells can contribute to craniofacial cartilages in a wild-type background. Collectively, these data suggest that zebrafish Zic2 plays a dual role during craniofacial development, contributing to two disparate aspects of craniofacial morphogenesis: (1) neural crest induction and migration, and (2) early

  9. Identification of high-risk Listeria monocytogenes serotypes in lineage I (serotype 1/2a, 1/2c, 3a and 3c) using multiplex PCR

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Aims: Using molecular subtyping techniques, Listeria monocytogenes is divided into three major phylogenetic lineages, and a multiplex PCR method can differentiate five L. monocytogenes subgroups: 1/2a-3a, 1/2c-3c, 1/2b-3b-7, 4b-4d-4e, and 4a-4c. In the current study, we conducted genome comparison...

  10. A chimeric Plasmodium falciparum Pfnbp2b/Pfnbp2a gene originated during asexual growth.

    PubMed

    Cortés, Alfred

    2005-02-01

    The Plasmodium falciparum line 3D7-A has an unusual invasion phenotype, such that it can invade enzyme-treated and mutant red blood cells that are resistant to invasion by other parasite lines. 3D7-A has a chimeric Pfnbp2b gene that contains part of the repeat region of the paralogous gene Pfnbp2a. This chimeric gene originated by spontaneous gene conversion during normal maintenance in culture, indicating that ectopic recombination and gene conversion during asexual growth are potentially important mechanisms participating in the evolution of paralogous genes in Plasmodium. However, the presence of the chimeric Pfnbp2b gene in 3D7-A was not associated with its peculiar invasion phenotype.

  11. Apically Linked Small Metallacarborane Clusters. Directed Synthesis and Structural Characterization of 7,7'-[CpCo(2,3-Et(2)C(2)B(4)H(3)](2) and [CpCo(2,3-Et(2)C(2)B(4)H(3)-7)](2)X Complexes (X = MeCH, HC=CH, C&tbd1;C)(,)(1).

    PubMed

    Curtis, Michael A.; Müller, Thomas; Beez, Volker; Pritzkow, Hans; Siebert, Walter; Grimes, Russell N.

    1997-08-13

    A series of novel bis(cobaltacarboranyl) (CoC(2)B(4))(2)X dicluster complexes whose B(7) (apex) atoms are linked by organic moieties involving sp-, sp(2)-, or sp(3)-hybridized carbon, or by a direct B(7)-B(7') bond, has been prepared by extension of the recently described "recapitation" method (Curtis, M. A.; et al. Inorg. Chem. 1996, 35, 6703) that entails treatment of 6-vertex nido-CoC(2)B(3) dianions with monoboron reagents. Reactions of Li(2)[nido-CpCo(Et(2)C(2)B(3)H(3))] in toluene with MeCH(BCl(2))(2) and with cis-(BCl(2))C(2)H(2) gave, respectively, [CpCo(2,3-Et(2)C(2)B(4)H(3)-7-)](2)MeCH (5) and cis-[CpCo(2,3-Et(2)C(2)B(4)H(3)-7-)](2)C(2)H(2) (6a) following chromatographic separation. Ultraviolet irradiation of 6a induced partial conversion to the trans isomer 6b, affording a 46:54 trans/cis equilibrium mixture in 84 h. Reactions of the same cobaltacarborane dianion with bis(catecholboryl)acetylene and with bis(catecholdiboryl) gave [CpCo(2,3-Et(2)C(2)B(4)H(3)-7-)](2)C(2) (7) and [CpCo(2,3-Et(2)C(2)B(4)H(3)-7-)](2) (8), respectively. The new complexes were isolated as air-stable, crystalline orange solids and were characterized from their (1)H, (11)B, and (13)C NMR, IR, UV-visible, and mass spectra, supported by X-ray crystallographic studies of 5, 6a, 7, and 8. Crystal data for 5: space group P2(1)ca (orthorhombic); a = 14.220(10) Å, b = 15.690(10) Å, c = 16.860(10) Å, Z = 4; R = 0.041 for 7485 independent reflections. Crystal data for 6a: space group C2/c (monoclinic); a = 12.849(6) Å, b = 11.435(6) Å, c = 25.619(13) Å, beta = 96.230(10) degrees; Z = 4; R = 0.036 for 5440 independent reflections. Crystal data for 7: space group P2(1)/n (monoclinic); a = 17.298(12) Å, b = 13.932(10) Å, c = 30.82(2) Å, beta = 96.34(5) degrees; Z = 8; R = 0.070 for 9632 independent reflections. Crystal data for 8: space group P&onemacr; (triclinic); a = 9.150(10) Å, b = 10.270(10) Å, c = 10.340(10) Å, alpha = 84.52(5) degrees, beta = 78.05(5) degrees, gamma = 68

  12. Anisotropic superconducting and normal state magnetic properties of single crystals of RNi*2*B*2*C compounds (R = Y, Gd, Dy, Ho, Er, and Tm)

    SciTech Connect

    Cho, B.

    1995-11-01

    The interaction of superconductivity with magnetism has been one of the most interesting and important phenomena in solid state physics since the 1950`s when small amounts of magnetic impurities were incorporated in superconductors. The discovery of the magnetic superconductors RNi{sub 2}B{sub 2}C (R = rare earth, Y) offers a new system to study this interaction. The wide ranges of superconducting transition (T{sub c}) and antiferromagnetic (AF) ordering temperatures (T{sub N}) (0 K {le} T{sub c} {le} 16 K, 0 K {le} T{sub N} {le} 20 K) give a good opportunity to observe a variety of interesting phenomena. Single crystals of high quality with appropriate size and mass are crucial in examining the anisotropic intrinsic properties. Single crystals have been grown successfully by an unusual high temperature flux method and characterized thoroughly by X-ray, electrical transport, magnetization, neutron scattering, scanning electron microscopy, and other measurements.

  13. Summary report on the fuel performance modeling of the AFC-2A, 2B irradiation experiments

    SciTech Connect

    Pavel G. Medvedev

    2013-09-01

    The primary objective of this work at the Idaho National Laboratory (INL) is to determine the fuel and cladding temperature history during irradiation of the AFC-2A, 2B transmutation metallic fuel alloy irradiation experiments containing transuranic and rare earth elements. Addition of the rare earth elements intends to simulate potential fission product carry-over from pyro-metallurgical reprocessing. Post irradiation examination of the AFC-2A, 2B rodlets revealed breaches in the rodlets and fuel melting which was attributed to the release of the fission gas into the helium gap between the rodlet cladding and the capsule which houses six individually encapsulated rodlets. This release is not anticipated during nominal operation of the AFC irradiation vehicle that features a double encapsulated design in which sodium bonded metallic fuel is separated from the ATR coolant by the cladding and the capsule walls. The modeling effort is focused on assessing effects of this unanticipated event on the fuel and cladding temperature with an objective to compare calculated results with the temperature limits of the fuel and the cladding.

  14. Role for serotonin2A (5-HT2A) and 2C (5-HT2C) receptors in experimental absence seizures.

    PubMed

    Venzi, Marcello; David, François; Bellet, Joachim; Cavaccini, Anna; Bombardi, Cristiano; Crunelli, Vincenzo; Di Giovanni, Giuseppe

    2016-09-01

    Absence seizures (ASs) are the hallmark of childhood/juvenile absence epilepsy. Monotherapy with first-line anti-absence drugs only controls ASs in 50% of patients, indicating the need for novel therapeutic targets. Since serotonin family-2 receptors (5-HT2Rs) are known to modulate neuronal activity in the cortico-thalamo-cortical loop, the main network involved in AS generation, we investigated the effect of selective 5-HT2AR and 5-HT2CR ligands on ASs in the Genetic Absence Epilepsy Rats from Strasbourg (GAERS), a well established polygenic rat model of these non-convulsive seizures. GAERS rats were implanted with fronto-parietal EEG electrodes under general anesthesia, and their ASs were later recorded under freely moving conditions before and after intraperitoneal administration of various 5-HT2AR and 5-HT2CR ligands. The 5-HT2A agonist TCB-2 dose-dependently decreased the total time spent in ASs, an effect that was blocked by the selective 5-HT2A antagonist MDL11,939. Both MDL11,939 and another selective 5-HT2A antagonist (M100,907) increased the length of individual seizures when injected alone. The 5-HT2C agonists lorcaserin and CP-809,101 dose-dependently suppressed ASs, an effect blocked by the selective 5-HT2C antagonist SB 242984. In summary, 5-HT2ARs and 5-HT2CRs negatively control the expression of experimental ASs, indicating that selective agonists at these 5-HT2R subtypes might be potential novel anti-absence drugs.

  15. Role for serotonin2A (5-HT2A) and 2C (5-HT2C) receptors in experimental absence seizures.

    PubMed

    Venzi, Marcello; David, François; Bellet, Joachim; Cavaccini, Anna; Bombardi, Cristiano; Crunelli, Vincenzo; Di Giovanni, Giuseppe

    2016-09-01

    Absence seizures (ASs) are the hallmark of childhood/juvenile absence epilepsy. Monotherapy with first-line anti-absence drugs only controls ASs in 50% of patients, indicating the need for novel therapeutic targets. Since serotonin family-2 receptors (5-HT2Rs) are known to modulate neuronal activity in the cortico-thalamo-cortical loop, the main network involved in AS generation, we investigated the effect of selective 5-HT2AR and 5-HT2CR ligands on ASs in the Genetic Absence Epilepsy Rats from Strasbourg (GAERS), a well established polygenic rat model of these non-convulsive seizures. GAERS rats were implanted with fronto-parietal EEG electrodes under general anesthesia, and their ASs were later recorded under freely moving conditions before and after intraperitoneal administration of various 5-HT2AR and 5-HT2CR ligands. The 5-HT2A agonist TCB-2 dose-dependently decreased the total time spent in ASs, an effect that was blocked by the selective 5-HT2A antagonist MDL11,939. Both MDL11,939 and another selective 5-HT2A antagonist (M100,907) increased the length of individual seizures when injected alone. The 5-HT2C agonists lorcaserin and CP-809,101 dose-dependently suppressed ASs, an effect blocked by the selective 5-HT2C antagonist SB 242984. In summary, 5-HT2ARs and 5-HT2CRs negatively control the expression of experimental ASs, indicating that selective agonists at these 5-HT2R subtypes might be potential novel anti-absence drugs. PMID:27085605

  16. Characterization of the NR1, NR2A, and NR2C receptor proteins.

    PubMed Central

    Köpke, A. K.; Bonk, I.; Sydow, S.; Menke, H.; Spiess, J.

    1993-01-01

    N-Methyl-D-aspartate (NMDA) receptor subunits were characterized with seven polyclonal antibodies. The antibodies were directed against NR1-A, NR2A-N1, and NR2C-N1, representing N-terminal sequences of the NR1, NR2A, and NR2C subunits, and against NR1-E, NR2A-C1, and NR2C-C1, derived from C-terminal sequences of these subunits. The anti-NR1-D antibody was raised against the putative internal loop of NR1. A size of 118 kDa was found in sodium dodecyl sulfate-polyacrylamide gel electrophoresis for NR1 (from rat brain) detected by anti-NR1-D and -NR1-E, but not anti-NR1-A. With the anti-NR1-A antibody, a 125-kDa protein was discovered that may represent a glutamate receptor not yet characterized. NR2A and NR2C were identified as proteins with sizes of 175 and 140 kDa, respectively. Enzymatic N-deglycosylation generated a 97-kDa protein from NR1, a 105-kDa protein from the 125-kDa protein, a 162-kDa protein from NR2A, and a 127-kDa protein from NR2C. In contrast to the deglycosylation product of the NR2A, the 97- and 127-kDa proteins derived from NR1 and NR2C, respectively, were found significantly smaller than the molecular masses of 103 and 141 kDa, respectively, predicted on the basis of DNA data. These products may represent truncated proteins. The tissue content of the NR1 and NR2A was high in bovine hippocampus and cortex but lower in the cerebellum. In contrast, NR2C was solely found in the cerebellum. The 125-kDa protein was highest in the cerebellum and cortex. PMID:8298456

  17. Impaired hippocampal synaptic plasticity and NR2A/2B expression ratio in remifentanil withdrawal rats.

    PubMed

    Wang, Yi-Yi; Liu, Shichang; Zhang, Nan; Yang, Jing; Zhang, Yinguo

    2016-03-01

    Remifentanil is a kind of synthetic opioid which has gained wide clinical acceptance by anesthesiologists. In this study, we attempted to test whether withdrawal effects on learning mechanisms can be triggered by repeated low-dose remifentanil treatment. Male Sprague-Dawley (SD) rats were subjected to remifentanil (50μg/kgs.c.) twice per day at 12h intervals for 15 days. When the animals of remifentanil group were withdrawn from remifentanil at 10h after the last injection, changes in open field test, Morris water maze test (MWM) and synaptic efficacy were examined in each group. We demonstrated that repeated exposure to 50μg/kg remifentanil produced enhanced locomotor activity indicating that a remifentanil addiction animal model in rats was established. MWM results showed that exposure to remifentanil had no influence on the spatial cognition. After withdrawal of remifentanil rats showed impaired spatial cognition. In electrophysiology test, remifentanil group rats showed a trend for a rightward shift of input/output relationship and significant deficits in maintenance of STP and LTP. Immunohistochemistry results demonstrated increased NR2A/NR2B ratio that should be included depression of LTP. In the whole-cell patch-clamp recording, after elimination from remifentanil incubation, mEPSC frequency was down regulated in hippocampal CA1 neurons, indicating that basal synaptic transmission were affected by remifentanil withdrawal. Taken together, the current findings demonstrate that the remifentanil withdrawn rats exhibit obvious impairment of hippocampus-dependent memory and synaptic plasticity. Increased hippocampal NR2A/NR2B expression ratio and the changes of basal synaptic transmission may participate in the impairment of LTP. PMID:26777139

  18. Hepatic CYP1A, 2B, 2C, 2E and 3A regulation by methoxychlor in male and female rats.

    PubMed

    Oropeza-Hernández, Luis F; López-Romero, Ricardo; Albores, Arnulfo

    2003-09-15

    The effect on liver cytochrome P450 (CYP) by i.p. injections of methoxychlor (MXC) in corn oil at 0, 100, 150, 200 or 250 mg/kg twice daily for 3 days was investigated in adult male and female Wistar rats. The MXC injection (100 mg/kg b.w.) caused a similar increase of total CYP content in males and females as compared with controls who received the vehicle only. In males, this increase continued up to 250 mg/kg. As to the induction of specific CYP activities, the effect of MXC was found to be sex dependent with three different patterns. Males showed the greatest increases of ethoxy- and methoxyresorufin-O-dealkylase (EROD and MROD, respectively), two CYP1A1/1A2-related activities. On the contrary, females were more responsive than males for pentoxyresorufin-O-dealkylase (PROD) and benzyloxyresorufin-O-dearylase (BROD), two CYP2B-related activities. Finally, p-nitrophenol hydroxylase (PNPH), a CYP2E1-related activity, showed a similar small, although statistically significant, increase for both sexes. As to CYP apoprotein levels, CYP1A1 and CYP2B1/2B2 showed greater increases in females than in males; whereas, interestingly, CYP2E1 induction was higher in males than in females. These results indicate overall that gender modulates CYP expression after MXC injection both qualitatively and quantitatively, and, therefore, this pesticide is not a pure PB inducer. Moreover, the statistically significant increase of CYP3A2 apoprotein expression observed in females and also, to a lower extent, in males, and the decrease of CYP2C11 apoprotein found in males, two sex-related enzymes, may explain the reported endocrine disrupting effect of MXC. The relevance of the different patterns of rat liver CYP induction observed after MXC treatment, in relationship to the speculated endocrine disrupting potential of MXC in humans potentially exposed to this pesticide, needs further investigation.

  19. Phytoremediation of the herbicides atrazine and metolachlor by transgenic rice plants expressing human CYP1A1, CYP2B6, and CYP2C19.

    PubMed

    Kawahigashi, Hiroyuki; Hirose, Sakiko; Ohkawa, Hideo; Ohkawa, Yasunobu

    2006-04-19

    This study evaluated the expression of human cytochrome P450 genes CYP1A1, CYP2B6, and CYP2C19 in rice plants (Oryza sativa cv. Nipponbare) introduced using the plasmid pIKBACH. The transgenic rice plants (pIKBACH rice plants) became more tolerant toward various herbicides than nontransgenic Nipponbare rice plants. Rice plants expressing pIKBACH grown in soil showed tolerance to the herbicides atrazine, metolachlor, and norflurazon and to a mixture of the three herbicides. The degradation of atrazine and metolachlor by pIKBACH rice plants was evaluated to confirm the metabolic activity of the introduced P450s. Although both pIKBACH and nontransgenic Nipponbare rice plants could decrease the amounts of the herbicides in plant tissue and culture medium, pIKBACH rice plants removed greater amounts in greenhouse experiments. The ability of pIKBACH rice plants to remove atrazine and metolachlor from soil was confirmed in large-scale experiments. The metabolism of herbicides by pIKBACH rice plants was enhanced by the introduced P450 species. Assuming that public and commercial acceptance is forthcoming, pIKBACH rice plants may become useful tools for the breeding of herbicide-tolerant crops and for phytoremediation of environmental pollution by organic chemicals. PMID:16608219

  20. Prediction of polaronlike vortices and a dissociation depinning transition in magnetic superconductors: the example of ErNi2B2C.

    PubMed

    Bulaevskii, Lev N; Lin, Shi-Zeng

    2012-07-13

    In borocarbide ErNi2B2C, the phase transition to the commensurate spin density wave at 2.3 K leaves 1/20 part of Ising-like Er spins practically free. Vortices polarize these spins nonuniformly and repolarize them when moving. At a low spin relaxation rate and at low bias currents, vortices carrying magnetic polarization clouds become polaronlike and their velocities are determined by the effective drag coefficient, which is significantly bigger than the Bardeen-Stephen (BS) one. As current increases, at a critical current J(c) vortices release polarization clouds and the velocity as well as the voltage in the I-V characteristics jump to values corresponding to the BS drag coefficient. The nonuniform components of the magnetic field and magnetization drop as velocity increases, resulting in weaker polarization and discontinuous dynamic dissociation depinning transition. As current decreases, on the way back, vortices are retrapped by polarization clouds at the current J(r)

  1. Activation of 5-HT2A/2C receptors reduces the excitability of cultured cortical neurons.

    PubMed

    Hu, Lingli; Liu, Chunhua; Dang, Minyan; Luo, Bin; Guo, Yiping; Wang, Haitao

    2016-10-01

    The abundant forebrain serotonergic projections are believed to modulate the activities of cortical neurons. 5-HT2 receptor among multiple subtypes of serotonin receptors contributes to the modulation of excitability, synaptic transmissions and plasticity. In the present study, whole-cell patch-clamp recording was adopted to examine whether activation of 5-HT2A/2C receptors would have any impact on the excitability of cultured cortical neurons. We found that 2,5-Dimethoxy-4-iodoamphetamine (DOI), a selective 5-HT2A/2C receptor agonist, rapidly and reversibly depressed spontaneous action potentials mimicking the effect of serotonin. The decreased excitability was also observed for current-evoked firing. Additionally DOI increased neuronal input resistance. Hyperpolarization-activated cyclic nucleotide-gated cationic channels (HCN) did not account for the inhibition of spontaneous firing. The synaptic contribution was ruled out in that DOI augmented excitation and attenuated inhibition to actually favor an increase in the excitability. Our findings revealed that activation of 5-HT2A/2C receptors reduces neuronal excitability, which would deepen our understanding of serotonergic modulation of cortical activities. PMID:27585751

  2. 3D-pharmacophore models for selective A2A and A2B adenosine receptor antagonists.

    PubMed

    Wei, Jing; Wang, Songqing; Gao, Shaofen; Dai, Xuedong; Gao, Qingzhi

    2007-01-01

    Three-dimensional pharmacophore models were generated for A2A and A2B adenosine receptors (ARs) based on highly selective A2A and A2B antagonists using the Catalyst program. The best pharmacophore model for selective A2A antagonists (Hypo-A2A) was obtained through a careful validation process. Four features contained in Hypo-A2A (one ring aromatic feature (R), one positively ionizable feature (P), one hydrogen bond acceptor lipid feature (L), and one hydrophobic feature (H)) seem to be essential for antagonists in terms of binding activity and A2A AR selectivity. The best pharmacophore model for selective A2B antagonists (Hypo-A2B) was elaborated by modifying the Catalyst common features (HipHop) hypotheses generated from the selective A2B antagonists training set. Hypo-A2B also consists of four features: one ring aromatic feature (R), one hydrophobic aliphatic feature (Z), and two hydrogen bond acceptor lipid features (L). All features play an important role in A2B AR binding affinity and are essential for A2B selectivity. Both A2A and A2B pharmacophore models have been validated toward a wide set of test molecules containing structurally diverse selective antagonists of all AR subtypes. They are capable of identifying correspondingly high potent antagonists and differentiating antagonists between subtypes. The results of our study will act as a valuable tool for retrieving structurally diverse compounds with desired biological activities and designing novel selective adenosine receptor ligands. PMID:17330954

  3. 3D-pharmacophore models for selective A2A and A2B adenosine receptor antagonists.

    PubMed

    Wei, Jing; Wang, Songqing; Gao, Shaofen; Dai, Xuedong; Gao, Qingzhi

    2007-01-01

    Three-dimensional pharmacophore models were generated for A2A and A2B adenosine receptors (ARs) based on highly selective A2A and A2B antagonists using the Catalyst program. The best pharmacophore model for selective A2A antagonists (Hypo-A2A) was obtained through a careful validation process. Four features contained in Hypo-A2A (one ring aromatic feature (R), one positively ionizable feature (P), one hydrogen bond acceptor lipid feature (L), and one hydrophobic feature (H)) seem to be essential for antagonists in terms of binding activity and A2A AR selectivity. The best pharmacophore model for selective A2B antagonists (Hypo-A2B) was elaborated by modifying the Catalyst common features (HipHop) hypotheses generated from the selective A2B antagonists training set. Hypo-A2B also consists of four features: one ring aromatic feature (R), one hydrophobic aliphatic feature (Z), and two hydrogen bond acceptor lipid features (L). All features play an important role in A2B AR binding affinity and are essential for A2B selectivity. Both A2A and A2B pharmacophore models have been validated toward a wide set of test molecules containing structurally diverse selective antagonists of all AR subtypes. They are capable of identifying correspondingly high potent antagonists and differentiating antagonists between subtypes. The results of our study will act as a valuable tool for retrieving structurally diverse compounds with desired biological activities and designing novel selective adenosine receptor ligands.

  4. Capsid proteins from PCV2a genotype confer greater protection against a PCV2b strain than those from PCV2b genotype in pigs: evidence for PCV2b strains becoming more predominant than PCV2a strains from 2000 to 2010s.

    PubMed

    Huang, Liping; Wang, Yiping; Wei, Yanwu; Chen, Dongjie; Liu, Dan; Du, Wenjuan; Xia, Deli; Wu, Hongli; Feng, Li; Liu, Changming

    2016-07-01

    Two major porcine circovirus type 2 (PCV2) genotypes, PCV2a and PCV2b, are recognized. PCV2a was predominant in the global pig population until 2000 while PCV2b became predominant from 2003 onward. The aim of this study was to analyze the immune protection conferred by two PCV2a and two PCV2b capsid proteins (Caps) in pigs challenged with a mutant PCV2b/YJ (mPCV2b/YJ) strain. Pigs vaccinated with PCV2a/LG-Cap and PCV2a/CL-Cap elicited significantly higher levels of PCV2-specific antibodies and neutralizing antibodies compared with PCV2b/JF-Cap and mPCV2b/YJ-Cap. Following a mPCV2b/YJ challenge, no viremia was detected in the PCV2a/LG-Cap and PCV2a/CL-Cap groups, while viremias were found in 20 and 40 % of the pigs in the PCV2b/JF-Cap and mPCV2b/YJ-Cap groups, respectively. Viral loads in the inguinal lymph nodes of pigs from the PCV2b/JF-Cap and mPCV2b/YJ-Cap groups were significantly higher than those in the PCV2a/LG-Cap and PCV2a/CL-Cap groups, but significantly lower than those of the challenge control group. Furthermore, PCV2 antigens were not detected in the inguinal lymph nodes of pigs from commercial vaccine groups, as well as the PCV2a/LG-Cap and PCV2a/CL-Cap groups, but were found in the challenge control (100 %, 5/5), PCV2b/JF-Cap (20 %, 1/5), and mPCV2b/YJ-Cap (20 %, 1/5) groups. These findings suggest that mPCV2b/YJ-Cap and PCV2b/JF-Cap were less immunogenic than PCV2a/LG-Cap and PCV2a/CL-Cap. We speculate that a genotypic shift from PCV2a to PCV2b might be the result of the majority of PCV2a strains being more immunogenic than the majority of PCV2b strains. These results provide a possible explanation for why PCV2b strains are more likely to cause epidemics than PCV2a strains. It tells us that PCV2 pathogenesis may be associated with its immunogenicity to some extent. PMID:27020283

  5. FACT disrupts nucleosome structure by binding H2A-H2B with conserved peptide motifs

    PubMed Central

    Kemble, David J.; McCullough, Laura L.; Whitby, Frank G.; Formosa, Tim; Hill, Christopher P.

    2015-01-01

    SUMMARY FACT, a heterodimer of Spt16 and Pob3, is an essential histone chaperone. We show that the H2A-H2B binding activity that is central to FACT function resides in short acidic regions near the C-termini of each subunit. Mutations throughout these regions impact binding and cause correlated phenotypes that range from mild to lethal, with the largest individual contributions unexpectedly coming from an aromatic residue and a nearby carboxylate residue within each domain. Spt16 and Pob3 bind overlapping sites on H2A-H2B, and Spt16-Pob3 heterodimers simultaneously bind two H2A-H2B dimers, the same stoichiometry as the components of a nucleosome. An Spt16:H2A-H2B crystal structure explains the biochemical and genetic data, provides a model for Pob3 binding, and implies a mechanism for FACT reorganization that we confirm biochemically. Moreover, unexpected similarity to binding of ANP32E and Swr1 with H2A.Z-H2B reveals that diverse H2A-H2B chaperones use common mechanisms of histone binding and regulating nucleosome functions. PMID:26455391

  6. Identification of natural recombinants derived from PCV2a and PCV2b.

    PubMed

    Hu, J; Zhai, S L; Zeng, S Y; Sun, B B; Deng, S F; Chen, H L; Zheng, Y; Wang, H X; Li, X P; Liu, J K; Cheng, S; Zhou, X; Zhai, J Q; Luo, M L

    2015-01-01

    Porcine circovirus type 2 (PCV2) is considered to be the main pathogen in PC-associated diseases, and significantly affects the global pig-producing industry. PCV2 continuously evolves by point mutations and genome recombinations. In the present study, we aimed to further identify recombinant PCV2 strains. We used polymerase chain reaction to detect PCV2 in the carcasses of pigs with suspected infections from different regions of Guangdong Province in China. DNA was extracted from samples with confirmed infection and full- genome amplification, sequencing, phylogenetic tree construction, gene recombination detection, and sequence alignment were performed in gene recombination analysis. Our results show that recombination occurred between the strains SHC (DQ104421) and ZhuJi2003 (AY579893). The recombination resulted in three recombinants: GD003 (KM503044), GD005 (KM487708), and GD008 (KM487709). Further analyses revealed that these novel recombinants appeared to result from recombination between the PCV2a and PCV2b strains, with crossover regions located in ORF2. This study was a comprehensive analysis that used several different methods, which demonstrated that a cluster of PCV2 strains resulted from the same type of inter-genotypic recombination pattern, with a breakpoint in the structural protein coding region. The results of our study provide both information on the recombination mechanism and disease pathogenesis and useful data for the prevention of PCV2 in the swine industry. PMID:26436503

  7. The real factor for polypeptide elongation in Dictyostelium cells is EF-2B, not EF-2A

    SciTech Connect

    Yoshino, Tomoko; Maeda, Yasuo; Amagai, Aiko . E-mail: aiamagai@mail.tains.tohoku.ac.jp

    2007-08-03

    Polypeptide elongation factor 2 (EF-2) plays an essential role in protein synthesis and is believed to be indispensable for cell proliferation. Recently, it has been demonstrated that there are two kinds of EF-2 (EF-2A and EF-2B with 76.6% of sequence identity at the amino acid level) in Dictyostelium discoideum. Although the knockout of EF-2A slightly impaired cytokinesis, EF-2A null cells exhibited almost normal protein synthesis and cell growth, suggesting that there is another molecule capable of compensating for EF-2 function. Since EF-2B is the most likely candidate, we examined its function using ef-2b knockdown cells prepared by the RNAi method. Our results strongly suggest that EF-2B is required for protein synthesis and cell proliferation, functioning as the real EF-2. Interestingly, the expressions of ef-2a and ef-2b mRNAs during development are reversely regulated, and the ef-2b expression is greatly augmented in ef-2a null cells.

  8. In vitro processing of dengue virus type 2 nonstructural proteins NS2A, NS2B, and NS3.

    PubMed Central

    Preugschat, F; Yao, C W; Strauss, J H

    1990-01-01

    We have tested the hypothesis that the flavivirus nonstructural protein NS3 is a viral proteinase that generates the termini of several nonstructural proteins by using an efficient in vitro expression system and monospecific antisera directed against the nonstructural proteins NS2B and NS3. A series of cDNA constructs was transcribed by using T7 RNA polymerase, and the RNA was translated in reticulocyte lysates. The resulting protein patterns indicated that proteolytic processing occurred in vitro to generate NS2B and NS3. The amino termini of NS2B and NS3 produced in vitro were found to be the same as the termini of NS2B and NS3 isolated from infected cells. Deletion analysis of cDNA constructs localized the protease domain within NS3 to the first 184 amino acids but did not eliminate the possibility that sequences within NS2B were also required for proper cleavage. Kinetic analysis of processing events in vitro and experiments to examine the sensitivity of processing to dilution suggested that an intramolecular cleavage between NS2A and NS2B preceded an intramolecular cleavage between NS2B and NS3. The data from these expression experiments confirm that NS3 is the viral proteinase responsible for cleavage events generating the amino termini of NS2B and NS3 and presumably for cleavages generating the termini of NS4A and NS5 as well. Images PMID:2143543

  9. Pharmacogenetics of CYP2B6, CYP2A6 and UGT2B7 in HIV treatment in African populations: focus on efavirenz and nevirapine.

    PubMed

    Čolić, Antoinette; Alessandrini, Marco; Pepper, Michael S

    2015-05-01

    The CYP450 and UGT enzymes are involved in phase I and phase II metabolism of the majority of clinically prescribed drugs, including the non-nucleoside reverse transcriptase inhibitors, efavirenz and nevirapine, used in the treatment of HIV/AIDS. Variations in the activity of these enzymes due to gene polymorphisms can affect an individual's drug response or may lead to adverse drug reactions. There is an inter-ethnic distribution in the frequency of these polymorphisms, with African populations exhibiting higher genetic diversity compared to other populations. African specific alleles with clinical relevance have also emerged. Given the high prevalence of HIV/AIDS in sub-Saharan Africa, understanding the frequency of pharmacogenetically relevant alleles in populations of African origin, and their impact on efavirenz and nevirapine metabolism, is becoming increasingly critical. This review aims to investigate ethnic variation of CYP2B6, CYP2A6 and UGT2B7, and to understand the pharmacogenetic relevance when comparing frequencies in African populations to other populations worldwide. PMID:25391641

  10. Nucleosome adaptability conferred by sequence and structural variations in histone H2A-H2B dimers.

    PubMed

    Shaytan, Alexey K; Landsman, David; Panchenko, Anna R

    2015-06-01

    Nucleosome variability is essential for their functions in compacting the chromatin structure and regulation of transcription, replication and cell reprogramming. The DNA molecule in nucleosomes is wrapped around an octamer composed of four types of core histones (H3, H4, H2A, H2B). Nucleosomes represent dynamic entities and may change their conformation, stability and binding properties by employing different sets of histone variants or by becoming post-translationally modified. There are many variants of histones H2A and H2B. Specific H2A and H2B variants may preferentially associate with each other resulting in different combinations of variants and leading to the increased combinatorial complexity of nucleosomes. In addition, the H2A-H2B dimer can be recognized and substituted by chaperones/remodelers as a distinct unit, can assemble independently and is stable during nucleosome unwinding. In this review we discuss how sequence and structural variations in H2A-H2B dimers may provide necessary complexity and confer the nucleosome functional variability.

  11. Nucleosome adaptability conferred by sequence and structural variations in histone H2A-H2B dimers

    PubMed Central

    Shaytan, Alexey K.; Landsman, David

    2015-01-01

    Nucleosome variability is essential for their functions in compacting the chromatin structure and regulation of transcription, replication and cell reprogramming. The DNA molecule in nucleosomes is wrapped around an octamer composed of four types of core histones (H3, H4, H2A, H2B). Nucleosomes represent dynamic entities and may change their conformation, stability and binding properties by employing different sets of histone variants or by becoming post-translationally modified. There are many variants of histones H2A and H2B. Specific H2A and H2B variants may preferentially associate with each other resulting in different combinations of variants and leading to the increased combinatorial complexity of nucleosomes. In addition, the H2A-H2B dimer can be recognized and substituted by chaperones/remodelers as a distinct unit, can assemble independently and is stable during nucleosome unwinding. In this review we discuss how sequence and structural variations in H2A-H2B dimers may provide necessary complexity and confer the nucleosome functional variability. PMID:25731851

  12. Molecular Determinants for Ligand Binding at Serotonin 5-HT2A and 5-HT2C GPCRs: Experimental Affinity Results Analyzed by Molecular Modeling and Ligand Docking Studies

    PubMed Central

    Sakhuja, Rajeev; Kondabolu, Krishnakanth; Canal, Clinton E.; Booth, Raymond G.

    2013-01-01

    Ligands that activate the serotonin 5-HT2C G protein-coupled receptor (GPCR) may be therapeutic for psychoses, addiction, and other neuropsychiatric disorders. Ligands that are antagonists at the closely related 5-HT2A GPCR also may treat neuropsychiatric disorders; in contrast, 5-HT2A activation may cause hallucinations. 5-HT2C-specific agonist drug design is challenging because 5-HT2 GPCRs share 80% transmembrane (TM) homology, same second messenger signaling, and no crystal structures are reported. To help delineate molecular determinants underlying differential binding and activation of 5-HT2 GPCRs, 5-HT2A, and 5-HT2C homology models were built from the β2-adrenergic GPCR crystal structure and equilibrated in a lipid phosphatidyl choline bilayer performing molecular dynamics simulations. Ligand docking studies at the 5-HT2 receptor models were conducted with the (2R, 4S)- and (2S, 4R)-enantiomers of the novel 5-HT2C agonist/5-HT2A/2B antagonist trans-4-phenyl-N,N-dimethyl-2-aminotetralin (PAT) and its 4′-chlorophenyl congners. Results indicate PAT–5-HT2 molecular interactions especially in TM domain V are important for the (2R, 4S) enantiomer, whereas, TM domain VI and VII interactions are more important for the (2S, 4R) enantiomer. PMID:23913978

  13. Serotonin 2A and 2B receptor-induced phrenic motor facilitation: differential requirement for spinal NADPH oxidase activity

    PubMed Central

    MacFarlane, P.M.; Vinit, S.; Mitchell, G.S.

    2011-01-01

    Acute intermittent hypoxia (AIH) facilitates phrenic motor output by a mechanism that requires spinal serotonin (type 2) receptor activation, NADPH oxidase activity and formation of reactive oxygen species (ROS). Episodic spinal serotonin (5-HT) receptor activation alone, without changes in oxygenation, is sufficient to elicit NADPH oxidase-dependent phrenic motor facilitation (pMF). Here we investigated: 1) whether serotonin 2A and/or 2B (5-HT2a/b) receptors are expressed in identified phrenic motor neurons, and 2) which receptor subtype is capable of eliciting NADPH-oxidase-dependent pMF. In anesthetized, artificially ventilated adult rats, episodic C4 intrathecal injections (3 × 6µl injections, 5 min intervals) of a 5-HT2a (DOI) or 5-HT2b (BW723C86) receptor agonist elicited progressive and sustained increases in integrated phrenic nerve burst amplitude (i.e. pMF), an effect lasting at least 90 minutes post-injection for both receptor subtypes. 5-HT2a and 5-HT2b receptor agonist-induced pMF were both blocked by selective antagonists (ketanserin and SB206553, respectively), but not by antagonists to the other receptor subtype. Single injections of either agonist failed to elicit pMF, demonstrating a need for episodic receptor activation. Phrenic motor neurons retrogradely labeled with cholera toxin B fragment expressed both 5-HT2a and 5-HT2b receptors. Pre-treatment with NADPH oxidase inhibitors (apocynin and DPI) blocked 5-HT2b, but not 5-HT2a-induced pMF. Thus, multiple spinal type 2 serotonin receptors elicit pMF, but they act via distinct mechanisms that differ in their requirement for NADPH oxidase activity. PMID:21223996

  14. Singular PCV2a or PCV2b infection results in apoptosis of hepatocytes in clinically affected gnotobiotic pigs

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Porcine circovirus type 2 (PCV2) which can be further subdivide into two main genotypes, PCV2a and PCV2b, is often clinically associated with respiratory signs, failure-to-thrive, and diarrhea. The precise pathogenesis of PCV2, and in particular its involvement in apoptosis, is controversial. The ob...

  15. Singular PCV2a or PCV2b Infection Results in Apoptosis of Hepatocytes in Clinically Affected Gnotobiotic Pigs

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Introduction: Systemic infection with porcine circovirus type 2 (PCV2) is often clinically associated with respiratory signs, failure to thrive and diarrhea [1]. Currently, PCV2 can be further subdivided into two main genotypes, PCV2a and PCV2b which under experimental conditions result in very simi...

  16. Astrocytic transactivation by alpha2A-adrenergic and 5-HT2B serotonergic signaling.

    PubMed

    Peng, Liang; Li, Baoman; Du, Ting; Kong, Ebenezer K C; Hu, Xiaoling; Zhang, Shiquen; Shan, Xiaolei; Zhang, Meixia

    2010-11-01

    EGF receptor transactivation has been known for more than ten years. It is a signal pathway in which a G-protein-coupled receptor (GPCR) signal leads to release of a growth factor, which in turn activates the EGF receptor-tyrosine kinase in the same or adjacent cells. Astrocytes express a number of GPCRs and play key roles in brain function. Astrocytic transactivation is of special interest, since its autocrine effect may regulate gene expression and alter cell functions in the cells themselves and its paracrine effect may provide additional opportunities for cross-talk between astrocytes and their neighbors, such as neurons. The signal pathways of EGF transactivation are complicated. This does not only apply to the pathways leading to shedding of growth factor(s), but also to the downstream signal pathways of the EGF receptor, i.e., MAPK and PI3K. The latter may vary according to the type of growth factor released, the sites of tyrosine phosphorylation on the EGF receptor, and the duration of the phosphorylation. Using primary cell cultures we have found that dexmedetomidine, a specific alpha(2)-adrenergic receptor, induced shedding of HB-EGF from astrocytes, which in turn transactivated EGF receptors and stimulated astrocytic c-Fos and FosB expression. At the same time released HB-EGF protected neurons from injury caused by H(2)O(2). We have also confirmed dexmedetomidine transactivation in the brain in vivo. EGF transactivation by 5-HT(2B) receptor stimulation was responsible for up-regulation of cPLA(2) in astrocytes by fluoxetine, an antidepressant and inhibitor of the serotonin transporter, which also is a specific 5-HT(2B) agonist. PMID:20450946

  17. Discovery and Characterization of GSK2801, a Selective Chemical Probe for the Bromodomains BAZ2A and BAZ2B

    PubMed Central

    2015-01-01

    Bromodomains are acetyl-lysine specific protein interaction domains that have recently emerged as a new target class for the development of inhibitors that modulate gene transcription. The two closely related bromodomain containing proteins BAZ2A and BAZ2B constitute the central scaffolding protein of the nucleolar remodeling complex (NoRC) that regulates the expression of noncoding RNAs. However, BAZ2 bromodomains have low predicted druggability and so far no selective inhibitors have been published. Here we report the development of GSK2801, a potent, selective and cell active acetyl-lysine competitive inhibitor of BAZ2A and BAZ2B bromodomains as well as the inactive control compound GSK8573. GSK2801 binds to BAZ2 bromodomains with dissociation constants (KD) of 136 and 257 nM for BAZ2B and BAZ2A, respectively. Crystal structures demonstrated a canonical acetyl-lysine competitive binding mode. Cellular activity was demonstrated using fluorescent recovery after photobleaching (FRAP) monitoring displacement of GFP-BAZ2A from acetylated chromatin. A pharmacokinetic study in mice showed that GSK2801 had reasonable in vivo exposure after oral dosing, with modest clearance and reasonable plasma stability. Thus, GSK2801 represents a versatile tool compound for cellular and in vivo studies to understand the role of BAZ2 bromodomains in chromatin biology. PMID:25799074

  18. The serotonin 5-HT2A and 5-HT2C receptors interact with specific sets of PDZ proteins.

    PubMed

    Bécamel, Carine; Gavarini, Sophie; Chanrion, Benjamin; Alonso, Gérard; Galéotti, Nathalie; Dumuis, Aline; Bockaert, Joël; Marin, Philippe

    2004-05-01

    The 5-hydroxytryptamine type 2A (5-HT(2A)) receptor and the 5-HT(2C) receptor are closely related members of the G-protein-coupled receptors activated by serotonin that share very similar pharmacological profiles and cellular signaling pathways. These receptors express a canonical class I PDZ ligand (SXV) at their C-terminal extremity. Here, we have identified proteins that interact with the PDZ ligand of the 5-HT(2A) and 5-HT(2C) receptors by a proteomic approach associating affinity chromatography using immobilized synthetic peptides encompassing the PDZ ligand and mass spectrometry. We report that both receptor C termini interact with specific sets of PDZ proteins in vitro. The 5-HT(2C) receptor but not the 5-HT(2A) receptor binds to the Veli-3.CASK.Mint1 ternary complex and to SAP102. In addition, the 5-HT(2C) receptor binds more strongly to PSD-95 and MPP-3 than the 5-HT(2A) receptor. In contrast, a robust interaction between the 5-HT(2A) receptor and the channel-interacting PDZ protein CIPP was found, whereas CIPP did not significantly associate with the 5-HT(2C) receptor. We also show that residues located at the -1 position and upstream the PDZ ligand in the C terminus of the 5-HT(2A) and 5-HT(2C) receptors are major determinants in their interaction with specific PDZ proteins. Immunofluorescence and electron microscopy studies strongly suggested that these specific interactions also take place in living cells and that the 5-HT(2) receptor-PDZ protein complexes occur in intracellular compartments. The interaction of the 5-HT(2A) and the 5-HT(2C) receptor with specific sets of PDZ proteins may contribute to their different signal transduction properties.

  19. Generation and Characterization of a CYP2A13/2B6/2F1-Transgenic Mouse Model

    PubMed Central

    Wei, Yuan; Wu, Hong; Li, Lei; Liu, Zhihua; Zhou, Xin; Zhang, Qing-Yu; Weng, Yan; D'Agostino, Jaime; Ling, Guoyu; Zhang, Xiuling; Kluetzman, Kerri; Yao, Yunyi

    2012-01-01

    CYP2A13, CYP2B6, and CYP2F1, which are encoded by neighboring cytochrome P450 genes on human chromosome 19, are active in the metabolic activation of many drugs, respiratory toxicants, and chemical carcinogens. To facilitate studies on the regulation and function of these human genes, we have generated a CYP2A13/2B6/2F1-transgenic (TG) mouse model (all *1 alleles). Homozygous transgenic mice are normal with respect to gross morphological features, development, and fertility. The tissue distribution of transgenic mRNA expression agreed well with the known respiratory tract-selective expression of CYP2A13 and CYP2F1 and hepatic expression of CYP2B6 in humans. CYP2A13 protein was detected through immunoblot analyses in the nasal mucosa (NM) (∼100 pmol/mg of microsomal protein; similar to the level of mouse CYP2A5) and the lung (∼0.2 pmol/mg of microsomal protein) but not in the liver of the TG mice. CYP2F1 protein, which could not be separated from mouse CYP2F2 in immunoblot analyses, was readily detected in the NM and lung but not the liver of TG/Cyp2f2-null mice, at levels 10- and 40-fold, respectively, lower than that of mouse CYP2F2 in the TG mice. CYP2B6 protein was detected in the liver (∼0.2 pmol/mg of microsomal protein) but not the NM or lung (with a detection limit of 0.04 pmol/mg of microsomal protein) of the TG mice. At least one transgenic protein (CYP2A13) seems to be active, because the NM of the TG mice had greater in vitro and in vivo activities in bioactivation of a CYP2A13 substrate, 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (a lung carcinogen), than did the NM of wild-type mice. PMID:22397853

  20. Targeted mutagenesis of aryl hydrocarbon receptor 2a and 2b genes in Atlantic killifish (Fundulus heteroclitus)

    PubMed Central

    Aluru, Neelakanteswar; Karchner, Sibel I.; Franks, Diana G.; Nacci, Diane; Champlin, Denise; Hahn, Mark E.

    2014-01-01

    Understanding molecular mechanisms of toxicity is facilitated by experimental manipulations, such as disruption of function by gene targeting, that are especially challenging in non-standard model species with limited genomic resources. While loss-of-function approaches have included gene knock-down using morpholino-modified oligonucleotides and random mutagenesis using mutagens or retroviruses, more recent approaches include targeted mutagenesis using zinc finger nuclease (ZFN), transcription activator-like effector nuclease (TALENs) and clustered regularly interspaced short palindromic repeats (CRISPR)-Cas9 technology. These latter methods provide more accessible opportunities to explore gene function in non-traditional model species. To facilitate evaluations of toxic mechanisms for important categories of aryl hydrocarbon pollutants, whose actions are known to be receptor mediated, we used ZFN and CRISPR-Cas9 approaches to generate aryl hydrocarbon receptor 2a (AHR2a) and AHR2b gene mutations in Atlantic killifish (Fundulus heteroclitus) embryos. This killifish is a particularly valuble non-traditional model for this study, with multiple paralogs of AHR whose functions are not well characterized. In addition, some populations of this species have evolved resistance to toxicants such as halogenated aromatic hydrocarbons. AHR-null killifish will be valuable for characterizing the role of the individual AHR paralogs in evolved resistance, as well as in normal development. We first used five-finger ZFNs targeting exons 1 and 3 of AHR2a. Subsequently, CRISPR-Cas9 guide RNAs were designed to target regions in exon 2 and 3 of AHR2a and AHR2b. We successfully induced frameshift mutations in AHR2a exon 3 with ZFN and CRISPR-Cas9 guide RNAs, with mutation frequencies of 10% and 16%, respectively. In AHR2b, mutations were induced using CRISPR-Cas9 guide RNAs targeting sites in both exon 2 (17%) and exon 3 (63%). We screened AHR2b exon 2 CRISPR-Cas9-injected embryos for

  1. Li2C2, a High-Capacity Cathode Material for Lithium Ion Batteries.

    PubMed

    Tian, Na; Gao, Yurui; Li, Yurong; Wang, Zhaoxiang; Song, Xiaoyan; Chen, Liquan

    2016-01-11

    As a typical alkaline earth metal carbide, lithium carbide (Li2C2) has the highest theoretical specific capacity (1400 mA h g(-1)) among all the reported lithium-containing cathode materials for lithium ion batteries. Herein, the feasibility of using Li2C2 as a cathode material was studied. The results show that at least half of the lithium can be extracted from Li2C2 and the reversible specific capacity reaches 700 mA h g(-1). The C≡C bond tends to rotate to form C4 (C≡C⋅⋅⋅C≡C) chains during lithium extraction, as indicated with the first-principles molecular dynamics (FPMD) simulation. The low electronic and ionic conductivity are believed to be responsible for the potential gap between charge and discharge, as is supported with density functional theory (DFT) calculations and Arrhenius fitting results. These findings illustrate the feasibility to use the alkali and alkaline earth metal carbides as high-capacity electrode materials for secondary batteries.

  2. Li2C2, a High-Capacity Cathode Material for Lithium Ion Batteries.

    PubMed

    Tian, Na; Gao, Yurui; Li, Yurong; Wang, Zhaoxiang; Song, Xiaoyan; Chen, Liquan

    2016-01-11

    As a typical alkaline earth metal carbide, lithium carbide (Li2C2) has the highest theoretical specific capacity (1400 mA h g(-1)) among all the reported lithium-containing cathode materials for lithium ion batteries. Herein, the feasibility of using Li2C2 as a cathode material was studied. The results show that at least half of the lithium can be extracted from Li2C2 and the reversible specific capacity reaches 700 mA h g(-1). The C≡C bond tends to rotate to form C4 (C≡C⋅⋅⋅C≡C) chains during lithium extraction, as indicated with the first-principles molecular dynamics (FPMD) simulation. The low electronic and ionic conductivity are believed to be responsible for the potential gap between charge and discharge, as is supported with density functional theory (DFT) calculations and Arrhenius fitting results. These findings illustrate the feasibility to use the alkali and alkaline earth metal carbides as high-capacity electrode materials for secondary batteries. PMID:26609636

  3. A long-standing mystery solved: the formation of 3-hydroxydesloratadine is catalyzed by CYP2C8 but prior glucuronidation of desloratadine by UDP-glucuronosyltransferase 2B10 is an obligatory requirement.

    PubMed

    Kazmi, Faraz; Barbara, Joanna E; Yerino, Phyllis; Parkinson, Andrew

    2015-04-01

    Desloratadine (Clarinex), the major active metabolite of loratadine (Claritin), is a nonsedating long-lasting antihistamine that is widely used for the treatment of allergic rhinitis and chronic idiopathic urticaria. For over 20 years, it has remained a mystery as to which enzymes are responsible for the formation of 3-hydroxydesloratadine, the major active human metabolite, largely due to the inability of any in vitro system tested thus far to generate this metabolite. In this study, we demonstrated that cryopreserved human hepatocytes (CHHs) form 3-hydroxydesloratadine and its corresponding O-glucuronide. CHHs catalyzed the formation of 3-hydroxydesloratadine with a Km of 1.6 μM and a Vmax of 1.3 pmol/min per million cells. Chemical inhibition of cytochrome P450 (P450) enzymes in CHHs demonstrated that gemfibrozil glucuronide (CYP2C8 inhibitor) and 1-aminobenzotriazole (general P450 inhibitor) inhibited 3-hydroxydesloratadine formation by 91% and 98%, respectively. Other inhibitors of CYP2C8 (gemfibrozil, montelukast, clopidogrel glucuronide, repaglinide, and cerivastatin) also caused extensive inhibition of 3-hydroxydesloratadine formation (73%-100%). Assessment of desloratadine, amodiaquine, and paclitaxel metabolism by a panel of individual CHHs demonstrated that CYP2C8 marker activity robustly correlated with 3-hydroxydesloratadine formation (r(2) of 0.70-0.90). Detailed mechanistic studies with sonicated or saponin-treated CHHs, human liver microsomes, and S9 fractions showed that both NADPH and UDP-glucuronic acid are required for 3-hydroxydesloratadine formation, and studies with recombinant UDP-glucuronosyltransferase (UGT) and P450 enzymes implicated the specific involvement of UGT2B10 in addition to CYP2C8. Overall, our results demonstrate for the first time that desloratadine glucuronidation by UGT2B10 followed by CYP2C8 oxidation and a deconjugation event are responsible for the formation of 3-hydroxydesloratadine. PMID:25595597

  4. Are licensed canine parvovirus (CPV2 and CPV2b) vaccines able to elicit protection against CPV2c subtype in puppies?: A systematic review of controlled clinical trials.

    PubMed

    Hernández-Blanco, Beatriz; Catala-López, Ferrán

    2015-10-22

    Severe gastroenteritis caused by canine parvovirus type 2 (CPV2) is a serious life-threatening disease in puppies less than 4-months of age. The emergence of new variants has provoked some concern about the cross-protection elicited by licensed canine parvovirus modified-live type 2 (CPV2) and type 2b (CPV2b) vaccines against the most recent subtype CPV2c. A systematic review was carried out to assess the efficacy of commercial vaccines. We conducted a literature search of Pub Med/MEDLINE from January 1990 to May 2014. This was supplemented by hand-searching of related citations and searches in Google/Google Scholar. Controlled clinical trials in which vaccinated puppies were challenged with CPV2c virus were evaluated. Reporting of outcome measures and results for vaccine efficacy were critically appraised through a variety of clinical signs, serological tests, virus shedding and the ability to overcome maternally derived antibodies (MDA) titres. Six controlled clinical trials were included in the review. In most cases, the results of the selected studies reported benefits in terms of clinical signs, serological tests and virus shedding. However, MDA interference was not considered or evaluated in 5 of the selected trials. No accurate definitions of baseline healthy status and/or clinical outcomes were provided. Methods of randomization, allocation concealment and blinding were usually poorly reported. As a result of the limited number of included studies matching the inclusion criteria, the small sample sizes, short follow-up and the methodological limitations observed, it was not possible to reach a final conclusion regarding the cross-protection of licensed CPV2 and CPV2b vaccines against the subtype 2c in puppies. Further and specifically designed trials are required in order to elucidate whether cross-protection is acquired from licensed CPV vaccines.

  5. Influence of Antipodally Coupled Iodine and Carbon Atoms on the Cage Structure of 9,12-I2-closo-1,2-C2B10H10: An Electron Diffraction and Computational Study.

    PubMed

    Vishnevskiy, Yury V; Tikhonov, Denis S; Reuter, Christian G; Mitzel, Norbert W; Hnyk, Drahomír; Holub, Josef; Wann, Derek A; Lane, Paul D; Berger, Raphael J F; Hayes, Stuart A

    2015-12-21

    Because of the comparable electron scattering abilities of carbon and boron, the electron diffraction structure of the C2v-symmetric molecule closo-1,2-C2B10H12 (1), one of the building blocks of boron cluster chemistry, is not as accurate as it could be. On that basis, we have prepared the known diiodo derivative of 1, 9,12-I2-closo-1,2-C2B10H10 (2), which has the same point-group symmetry as 1 but in which the presence of iodine atoms, with their much stronger ability to scatter electrons, ensures much better structural characterization of the C2B10 icosahedral core. Furthermore, the influence on the C2B10 geometry in 2 of the antipodally positioned iodine substituents with respect to both carbon atoms has been examined using the concerted application of gas electron diffraction and quantum chemical calculations at the MP2 and density functional theory (DFT) levels. The experimental and computed molecular geometries are in good overall agreement. Molecular dynamics simulations used to obtain vibrational parameters, which are needed for analyzing the electron diffraction data, have been performed for the first time for this class of compound. According to DFT calculations at the ZORA-SO/BP86 level, the (11)B chemical shifts of the boron atoms to which the iodine substituents are bonded are dominated by spin-orbit coupling. Magnetically induced currents within 2 have been calculated and compared to those for [B12H12](2-), the latter adopting a regular icosahedral structure with Ih point-group symmetry. Similar total current strengths are found but with a certain anisotropy, suggesting that spherical aromaticity is present; electron delocalization in the plane of the hetero atoms in 2 is slightly hindered compared to that for [B12H12](2-), presumably because of the departure from ideal icosahedral symmetry.

  6. GH indirectly enhances the regeneration of transgenic zebrafish fins through IGF2a and IGF2b.

    PubMed

    Nornberg, Bruna Félix; Almeida, Daniela Volcan; Figueiredo, Márcio Azevedo; Marins, Luis Fernando

    2016-10-01

    The somatotropic axis, composed essentially of the growth hormone (GH) and insulin-like growth factors (IGFs), is the main regulator of somatic growth in vertebrates. However, these protein hormones are also involved in various other major physiological processes. Although the importance of IGFs in mechanisms involving tissue regeneration has already been established, little is known regarding the direct effects of GH in these processes. In this study, we used a transgenic zebrafish (Danio rerio) model, which overexpresses GH from the beta-actin constitutive promoter. The regenerative ability of the caudal fin was assessed after repeated amputations, as well as the expression of genes related to the GH/IGF axis. The results revealed that GH overexpression increased the regenerated area of the caudal fin in transgenic fish after the second amputation. Transgenic fish also presented a decrease in gene expression of the GH receptor (ghrb), in opposition to the increased expression of the IGF1 receptors (igf1ra and igf1rb). These results suggest that transgenic fish have a higher sensitivity to IGFs than to GH during fin regeneration. With respect to the different IGFs produced locally, a decrease in igf1a expression and a significant increase in both igf2a and igf2b expression was observed, suggesting that igf1a is not directly involved in fin regeneration. Overall, the results revealed that excess GH enhances fin regeneration in zebrafish through igf2a and igf2b expression, acting indirectly on this major physiological process.

  7. 77 FR 59670 - Electronic Filing of H-2A and H-2B Labor Certification Applications Through the iCERT Visa Portal...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-09-28

    ... Employment and Training Administration Electronic Filing of H-2A and H-2B Labor Certification Applications... under the H-2A and H-2B visa programs through the Department of Labor's (Department) iCERT Visa Portal... the Department's decisions. Employers or their authorized representatives will be able to submit...

  8. Plakophilins 2a and 2b: constitutive proteins of dual location in the karyoplasm and the desmosomal plaque

    PubMed Central

    1996-01-01

    Using antibodies and recombinant DNA techniques, we have identified plakophilin 2, a novel desmosomal plaque protein of M(r) 100,000 (estimated from SDS-PAGE), which is a member of the arm-repeat family of proteins and can occur in two splice forms (2a and 2b) because of the insertion of a 44 amino acid (aa)-encoding exon. In its aa sequence (837 and 881 aa, calculated pIs: 9.33 and 9.38, mol wts 92,750 and 97,410 kD), it is conspicuously related to the 80-kD plakophilin 1, with which it shares a central region of 9 repeats of the arm-motif, preceeded by a long head region and followed by a very short (11 aa) carboxy-terminal sequence. Plakophilin 2 and its mRNA have been detected in a wide range of tissues and cell types, including cells devoid of desmosomes. By light and electron microscopical immunolocalization, plakophilin 2 has been localized to plaques of desmosomes of one-layered ("simple") and complex epithelia, carcinomas, diverse epithelium-derived cell culture lines, as well as cardiac tissue and the dendritic reticulum cells of lymphatic germinal centers, i.e., desmosomes in which plakophilin 1 is not detected. However, plakophilin 2 has also been localized in the desmosomes of certain but not all stratified epithelia where it coexists with plakophilin 1. Remarkably, plakophilin 2 is also enriched in the karyoplasm of a wide range of cell types, including many that lack desmosomes and in which, therefore, the nuclear state is the only locally enriched form of plakophilin 2 present. We conclude that plakophilins 2a and 2b are basic nuclear proteins that in certain cell types additionally assemble with other proteins to form the desmosomal plaque and serve general nuclear functions as well as a function specific to many but not all desmosomes. PMID:8922383

  9. The MATROSHKA experiment: results and comparison from extravehicular activity (MTR-1) and intravehicular activity (MTR-2A/2B) exposure.

    PubMed

    Berger, Thomas; Bilski, Paweł; Hajek, Michael; Puchalska, Monika; Reitz, Günther

    2013-12-01

    Astronauts working and living in space are exposed to considerably higher doses and different qualities of ionizing radiation than people on Earth. The multilateral MATROSHKA (MTR) experiment, coordinated by the German Aerospace Center, represents the most comprehensive effort to date in radiation protection dosimetry in space using an anthropomorphic upper-torso phantom used for radiotherapy treatment planning. The anthropomorphic upper-torso phantom maps the radiation distribution as a simulated human body installed outside (MTR-1) and inside different compartments (MTR-2A: Pirs; MTR-2B: Zvezda) of the Russian Segment of the International Space Station. Thermoluminescence dosimeters arranged in a 2.54 cm orthogonal grid, at the site of vital organs and on the surface of the phantom allow for visualization of the absorbed dose distribution with superior spatial resolution. These results should help improve the estimation of radiation risks for long-term human space exploration and support benchmarking of radiation transport codes.

  10. Simvastatin enhances NMDA receptor GluN2B expression and phosphorylation of GluN2B and GluN2A through increased histone acetylation and Src signaling in hippocampal CA1 neurons.

    PubMed

    Chen, Tingting; Zhang, Baofeng; Li, Guoxi; Chen, Lei; Chen, Ling

    2016-08-01

    Simvastatin (SV) can improve cognitive deficits in Alzheimer's disease patients and mice. Herein, we report that the administration of SV (20 mg/kg) for 5 days in mice (SV-mice) or the treatment of slices with SV (10 μM) for 4 h (SV-slices) could increase the density of NMDA-evoked inward currents (INMDA) in hippocampal CA1 pyramidal cells, which were blocked by farnesol (FOH) that converts farnesyl pyrophosphate (FPP), but not geranylgeraniol (GGOH) that increases geranylgeranylpyrophosphate (GGPP). Sensitivity of INMDA to ifenprodil in SV-mice or SV-slices was significantly increased. The levels of hippocampal GluN2B and GluN2A or Src phosphorylation in SV-mice or SV-slices were higher than controls, which were sensitive to FOH. The Src inhibitor PP2 could inhibit the SV-enhanced phosphorylation of GluN2B and GluN2A and SV-augmented INMDA, but PI3K inhibitor LY294002 did not. The levels of GluN2B mRNA and protein were elevated in SV-mice, which was abolished by FOH, but not by GGOH or PP2. Furthermore, the histone H3K9 and H3K27 acetylation of GluN2B promoter was increased in SV-mice, which was suppressed by FOH rather than GGOH or PP2. In control mice and slices, the reduction of FPP by farnesyl transferase inhibitor could increase the levels of GluN2B expression, the histone H3K9 and H3K27 acetylation and enhance the phosphorylation of GluN2B, GluN2A and Src. The findings indicate that the administration of SV can enhance GluN2B expression and GluN2B and GluN2A phosphorylation leading to augmentation of NMDAR activity through reducing FPP to increase histone acetylation of GluN2B and Src signaling.

  11. Chaperone Nap1 shields histone surfaces used in a nucleosome and can put H2A-H2B in an unconventional tetrameric form.

    PubMed

    D'Arcy, Sheena; Martin, Kyle W; Panchenko, Tanya; Chen, Xu; Bergeron, Serge; Stargell, Laurie A; Black, Ben E; Luger, Karolin

    2013-09-12

    The histone H2A-H2B heterodimer is an integral component of the nucleosome. The cellular localization and deposition of H2A-H2B into chromatin is regulated by numerous factors, including histone chaperones such as nucleosome assembly protein 1 (Nap1). We use hydrogen-deuterium exchange coupled to mass spectrometry to characterize H2A-H2B and Nap1. Unexpectedly, we find that at low ionic strength, the α helices in H2A-H2B are frequently sampling partially disordered conformations and that binding to Nap1 reduces this conformational sampling. We identify the interaction surface between H2A-H2B and Nap1 and confirm its relevance both in vitro and in vivo. We show that two copies of H2A-H2B bound to a Nap1 homodimer form a tetramer with contacts between H2B chains similar to those in the four-helix bundle structural motif. The organization of the complex reveals that Nap1 competes with histone-DNA and interhistone interactions observed in the nucleosome, thereby regulating the availability of histones for chromatin assembly. PMID:23973327

  12. Chaperone Nap1 shields histone surfaces used in a nucleosome and can put H2A-H2B in an unconventional tetrameric form

    PubMed Central

    D’Arcy, Sheena; Martin, Kyle W.; Panchenko, Tanya; Chen, Xu; Bergeron, Serge; Stargell, Laurie A.; Black, Ben E.; Luger, Karolin

    2013-01-01

    Summary The histone H2A-H2B heterodimer is an integral component of the nucleosome. The cellular localization and deposition of H2A-H2B into chromatin is regulated by numerous factors including histone chaperones such as Nucleosome Assembly Protein 1 (Nap1). We use hydrogen-deuterium exchange coupled to mass spectrometry to characterize H2A-H2B and Nap1. Unexpectedly, we find that at low ionic strength the α-helices in H2A-H2B are frequently sampling partially disordered conformations, and that binding to Nap1 reduces this conformational sampling. We identify the interaction surface between H2A-H2B and Nap1, and confirm its relevance both in vitro and in vivo. We show that two copies of H2A-H2B bound to a Nap1 homodimer form a tetramer with contacts between H2B chains similar to those in the four-helix bundle structural motif. The organization of the complex reveals that Nap1 competes with histone-DNA and inter-histone interactions observed in the nucleosome, thereby regulating the availability of histones for chromatin assembly. PMID:23973327

  13. Synthesis and Structure–Activity Relationships of N-Benzyl Phenethylamines as 5-HT2A/2C Agonists

    PubMed Central

    2014-01-01

    N-Benzyl substitution of 5-HT2A receptor agonists of the phenethylamine structural class of psychedelics (such as 4-bromo-2,5-dimethoxyphenethylamine, often referred to as 2C-B) confer a significant increase in binding affinity as well as functional activity of the receptor. We have prepared a series of 48 compounds with structural variations in both the phenethylamine and N-benzyl part of the molecule to determine the effects on receptor binding affinity and functional activity at 5-HT2A and 5-HT2C receptors. The compounds generally had high affinity for the 5-HT2A receptor with 8b having the highest affinity at 0.29 nM but with several other compounds also exhibiting subnanomolar binding affinities. The functional activity of the compounds was distributed over a wider range with 1b being the most potent at 0.074 nM. Most of the compounds exhibited low to moderate selectivity (1- to 40-fold) for the 5-HT2A receptor in the binding assays, although one compound 6b showed an impressive 100-fold selectivity for the 5-HT2A receptor. In the functional assay, selectivity was generally higher with 1b being more than 400-fold selective for the 5-HT2A receptor. PMID:24397362

  14. Specificity protein 4 functionally regulates the transcription of NMDA receptor subunits GluN1, GluN2A, and GluN2B.

    PubMed

    Priya, Anusha; Johar, Kaid; Wong-Riley, Margaret T T

    2013-12-01

    N-Methyl-d-aspartate (NMDA) receptors are major glutamatergic receptors involved in most excitatory neurotransmission in the brain. The transcriptional regulation of NMDA receptors is not fully understood. Previously, we found that the GluN1 and GluN2B subunits of the NMDA receptor are regulated by nuclear respiratory factors 1 and 2 (NRF-1 and NRF-2). NRF-1 and NRF-2 also regulate all 13 subunits of cytochrome c oxidase (COX), a critical energy-generating enzyme, thereby coupling neuronal activity and energy metabolism at the transcriptional level. Specificity protein (Sp) is a family of transcription factors that bind to GC-rich regions, with Sp1, Sp3, and Sp4 all binding to the same cis- motifs. Sp1 and Sp3 are ubiquitously expressed, whereas Sp4 expression is restricted to neurons and testicular cells. Recently, we found that the Sp1 factor regulates all subunits of COX. The goal of the present study was to test our hypothesis that the Sp factors also regulate specific subunits of NMDA receptors, and that they function with NRF-1 and NRF-2 via one of three mechanisms: complementary, concurrent and parallel, or a combination of complementary and concurrent/parallel. By means of multiple approaches we found that Sp4 functionally regulated GluN1, GluN2A, and GluN2B, but not GluN2C. On the other hand, Sp1 and Sp3 did not regulate these subunits as previously thought. Our data suggest that Sp4 operates in a complementary and concurrent/parallel manner with NRF-1 and NRF-2 to mediate the tight coupling between energy metabolism and neuronal activity at the molecular level.

  15. Mouse histone H2A and H2B genes: four functional genes and a pseudogene undergoing gene conversion with a closely linked functional gene.

    PubMed Central

    Liu, T J; Liu, L; Marzluff, W F

    1987-01-01

    The sequence of five mouse histone genes, two H2a and three H2b genes on chromosome 13 has been determined. The three H2b genes all code for different proteins, each differing in two amino acids from the others. The H2b specific elements present 5' to H2b genes from other species are present in all three mouse H2b genes. All three H2b genes are expressed in the same relative amounts in three different mouse cell lines and fetal mice. The H2b gene with the H2b specific sequence closest to the TATAA sequence is expressed in the highest amount. One of the H2a genes lacks the first 9 amino acids, the promoter region, the last 3 amino acids and contains an altered 3' end sequence. Despite these multiple defects, there is only one nucleotide change between the two H2a genes from codon 9 to 126. This indicates that a recent gene conversion has occurred between these two genes. The similarity of the nucleotide sequences in the coding regions of mouse histone genes is probably due to gene conversion events targeted precisely at the coding region. Images PMID:3562244

  16. Histone Chaperone Nap1 Is a Major Regulator of Histone H2A-H2B Dynamics at the Inducible GAL Locus

    PubMed Central

    Chen, Xu; D'Arcy, Sheena; Radebaugh, Catherine A.; Krzizike, Daniel D.; Giebler, Holli A.; Huang, Liangquan; Nyborg, Jennifer K.; Luger, Karolin

    2016-01-01

    Histone chaperones, like nucleosome assembly protein 1 (Nap1), play a critical role in the maintenance of chromatin architecture. Here, we use the GAL locus in Saccharomyces cerevisiae to investigate the influence of Nap1 on chromatin structure and histone dynamics during distinct transcriptional states. When the GAL locus is not expressed, cells lacking Nap1 show an accumulation of histone H2A-H2B but not histone H3-H4 at this locus. Excess H2A-H2B interacts with the linker DNA between nucleosomes, and the interaction is independent of the inherent DNA-binding affinity of H2A-H2B for these particular sequences as measured in vitro. When the GAL locus is transcribed, excess H2A-H2B is reversed, and levels of all chromatin-bound histones are depleted in cells lacking Nap1. We developed an in vivo system to measure histone exchange at the GAL locus and observed considerable variability in the rate of exchange across the locus in wild-type cells. We recapitulate this variability with in vitro nucleosome reconstitutions, which suggests a contribution of DNA sequence to histone dynamics. We also find that Nap1 is required for transcription-dependent H2A-H2B exchange. Altogether, these results indicate that Nap1 is essential for maintaining proper chromatin composition and modulating the exchange of H2A-H2B in vivo. PMID:26884462

  17. Histone Chaperone Nap1 Is a Major Regulator of Histone H2A-H2B Dynamics at the Inducible GAL Locus.

    PubMed

    Chen, Xu; D'Arcy, Sheena; Radebaugh, Catherine A; Krzizike, Daniel D; Giebler, Holli A; Huang, Liangquan; Nyborg, Jennifer K; Luger, Karolin; Stargell, Laurie A

    2016-04-01

    Histone chaperones, like nucleosome assembly protein 1 (Nap1), play a critical role in the maintenance of chromatin architecture. Here, we use the GAL locus in Saccharomyces cerevisiae to investigate the influence of Nap1 on chromatin structure and histone dynamics during distinct transcriptional states. When the GAL locus is not expressed, cells lacking Nap1 show an accumulation of histone H2A-H2B but not histone H3-H4 at this locus. Excess H2A-H2B interacts with the linker DNA between nucleosomes, and the interaction is independent of the inherent DNA-binding affinity of H2A-H2B for these particular sequences as measured in vitro When the GAL locus is transcribed, excess H2A-H2B is reversed, and levels of all chromatin-bound histones are depleted in cells lacking Nap1. We developed an in vivo system to measure histone exchange at the GAL locus and observed considerable variability in the rate of exchange across the locus in wild-type cells. We recapitulate this variability with in vitro nucleosome reconstitutions, which suggests a contribution of DNA sequence to histone dynamics. We also find that Nap1 is required for transcription-dependent H2A-H2B exchange. Altogether, these results indicate that Nap1 is essential for maintaining proper chromatin composition and modulating the exchange of H2A-H2B in vivo. PMID:26884462

  18. Origin and evolution of GATA2a and GATA2b in teleosts: insights from tongue sole, Cynoglossus semilaevis.

    PubMed

    Liu, Jinxiang; Jiang, Jiajun; Wang, Zhongkai; He, Yan; Zhang, Quanqi

    2016-01-01

    Background. Following the two rounds of whole-genome duplication that occurred during deuterostome evolution, a third genome duplication occurred in the lineage of teleost fish and is considered to be responsible for much of the biological diversification within the lineage. GATA2, a member of GATA family of transcription factors, is an important regulator of gene expression in hematopoietic cell in mammals, yet the role of this gene or its putative paralogs in ray-finned fishes remains relatively unknown. Methods. In this study, we attempted to identify GATA2 sequences from the transcriptomes and genomes of multiple teleosts using the bioinformatic tools MrBayes, MEME, and PAML. Following identification, comparative analysis of genome structure, molecular evolution rate, and expression by real-time qPCR were used to predict functional divergence of GATA2 paralogs and their relative transcription in organs of female and male tongue soles (Cynoglossus semilaevis). Results. Two teleost GATA2 genes were identified in the transcriptomes of tongue sole and Japanese flounder (Paralichthysolivaceus). Synteny and phylogenetic analysis confirmed that the two genes likely originated from the teleost-specific genome duplication . Additionally, selection pressure analysis predicted these gene duplicates to have undergone purifying selection and possible divergent new functions. This was supported by differential expression pattern of GATA2a and GATA2b observed in organs of female and male tongue soles. Discussion. Our results indicate that two GATA2 genes originating from the first teleost-specific genome duplication have remained transcriptionally active in some fish species and have likely undergone neofunctionalization. This knowledge provides novel insights into the evolution of the teleost GATA2 genes and constituted important groundwork for further research on the GATA gene family. PMID:27019782

  19. Origin and evolution of GATA2a and GATA2b in teleosts: insights from tongue sole, Cynoglossus semilaevis

    PubMed Central

    Liu, Jinxiang; Jiang, Jiajun; Wang, Zhongkai; He, Yan

    2016-01-01

    Background. Following the two rounds of whole-genome duplication that occurred during deuterostome evolution, a third genome duplication occurred in the lineage of teleost fish and is considered to be responsible for much of the biological diversification within the lineage. GATA2, a member of GATA family of transcription factors, is an important regulator of gene expression in hematopoietic cell in mammals, yet the role of this gene or its putative paralogs in ray-finned fishes remains relatively unknown. Methods. In this study, we attempted to identify GATA2 sequences from the transcriptomes and genomes of multiple teleosts using the bioinformatic tools MrBayes, MEME, and PAML. Following identification, comparative analysis of genome structure, molecular evolution rate, and expression by real-time qPCR were used to predict functional divergence of GATA2 paralogs and their relative transcription in organs of female and male tongue soles (Cynoglossus semilaevis). Results. Two teleost GATA2 genes were identified in the transcriptomes of tongue sole and Japanese flounder (Paralichthysolivaceus). Synteny and phylogenetic analysis confirmed that the two genes likely originated from the teleost-specific genome duplication . Additionally, selection pressure analysis predicted these gene duplicates to have undergone purifying selection and possible divergent new functions. This was supported by differential expression pattern of GATA2a and GATA2b observed in organs of female and male tongue soles. Discussion. Our results indicate that two GATA2 genes originating from the first teleost-specific genome duplication have remained transcriptionally active in some fish species and have likely undergone neofunctionalization. This knowledge provides novel insights into the evolution of the teleost GATA2 genes and constituted important groundwork for further research on the GATA gene family. PMID:27019782

  20. Clozapine, but not olanzapine, disrupts conditioned avoidance response in rats by antagonizing 5-HT2A/2C receptors.

    PubMed

    Li, Ming; Sun, Tao; Mead, Alexa

    2012-04-01

    The present study was designed to assess the role of 5-HT(2A/2C) receptors in the acute and repeated effect of clozapine and olanzapine in a rat conditioned avoidance response model, a validated model of antipsychotic activity. Male Sprague-Dawley rats that were previously treated with either phencyclidine (0.5-2.0 mg/kg, sc), amphetamine (1.25-5.0 mg/kg, sc), or saline and tested in a prepulse inhibition of acoustic startle study were used. They were first trained to acquire avoidance response to a white noise (CS1) and a pure tone (CS2) that differed in their ability to predict the occurrence of footshock. Those who acquired avoidance response were administered with clozapine (10.0 mg/kg, sc) or olanzapine (1.0 mg/kg, sc) together with either saline or 1-2,5-dimethoxy-4-iodo-amphetamine (DOI, a selective 5-HT(2A/2C) agonist, 1.0 or 2.5 mg/kg, sc), and their conditioned avoidance responses were tested for four consecutive days. After two drug-free retraining days, the long-term repeated effect was assessed in a challenge test during which all rats were injected with a low dose of clozapine (5 mg/kg, sc) or olanzapine (0.5 mg/kg). Results show that pretreatment of DOI dose-dependently reversed the acute disruptive effect of clozapine on both CS1 and CS2 avoidance responses, whereas it had little effect in reversing the acute effect of olanzapine. On the challenge test, pretreatment of DOI did not alter the clozapine-induced tolerance or the olanzapine-induced sensitization effect. These results confirmed our previous findings and suggest that clozapine, but not olanzapine, acts on through 5-HT(2A/2C) receptors to achieve its acute avoidance disruptive effect and likely its therapeutic effects. The long-term clozapine tolerance and olanzapine sensitization effects appear to be mediated by non-5-HT(2A/2C) receptors.

  1. The silent point mutations at the cleavage site of 2A/2B have no effect on the self-cleavage activity of 2A of foot-and-mouth disease virus.

    PubMed

    Gao, Zong-liang; Zhou, Jian-hua; Zhang, Jie; Ding, Yao-zhong; Liu, Yong-sheng

    2014-12-01

    The 2A region of the foot-and-mouth disease virus (FMDV) polyprotein is 18 amino acids in length, and 2A self-cleavage site (2A/2B) contains a conserved amino acid motif G2A/P2B. To investigate the synonymous codon usage for Glycine at the 2A/2B cleavage site of FMDV, 66 2A/2B1 nucleotide sequences were aligned and found that the synonymous codon usage of G2A is conserved and GGG was the most frequently used. To examine the role of synonymous codons for G2A in self-cleavage efficiency of 2A/2B, recombinant constructs which contains the chloramphenicol acetyltransferase protein (CAT) and enhanced green fluorescent protein (EGFP) linked by the FMDV 2A sequence with four synonymous codons for G2A were produced. The activities of all the F2As based plasmids were determined in CHO cells. The results showed that the synonymous codon usage patterns for G2A at the cleavage site (2A/2B) have no effect on the cleavage efficiency. This suggests that the synonymous codon usage of 2A peptide has no effect on the cleavage efficiency of FMDV 2A element. PMID:25152485

  2. A commercial PCV2a-based vaccine significantly reduces PCV2b transmission in experimental conditions.

    PubMed

    Rose, N; Andraud, M; Bigault, L; Jestin, A; Grasland, B

    2016-07-19

    Transmission characteristics of PCV2 have been compared between vaccinated and non-vaccinated pigs in experimental conditions. Twenty-four Specific Pathogen Free (SPF) piglets, vaccinated against PCV2 at 3weeks of age (PCV2a recombinant CAP protein-based vaccine), were inoculated at 15days post-vaccination with a PCV2b inoculum (6⋅10(5) TCID50), and put in contact with 24 vaccinated SPF piglets during 42days post-inoculation. Those piglets were shared in six replicates of a contact trial involving 4 inoculated piglets mingled with 4 susceptible SPF piglets. Two replicates of a similar contact trial were made with non-vaccinated pigs. Non vaccinated animals received a placebo at vaccination time and were inoculated the same way and at the same time as the vaccinated group. All the animals were monitored twice weekly using quantitative real-time PCR and ELISA for serology until 42days post-inoculation. The frequency of infection and the PCV2 genome load in sera of the vaccinated pigs were significantly reduced compared to the non-vaccinated animals. The duration of infectiousness was significantly different between vaccinated and non-vaccinated groups (16.6days [14.7;18.4] and 26.6days [22.9;30.4] respectively). The transmission rate was also considerably decreased in vaccinated pigs (β=0.09 [0.05-0.14] compared to β=0.19 [0.11-0.32] in non-vaccinated pigs). This led to an estimated reproduction ratio of 1.5 [95% CI 0.8 - 2.2] in vaccinated animals versus 5.1 [95% CI 2.5 - 8.2] in non-vaccinated pigs when merging data of this experiment with previous trials carried out in same conditions. PMID:27318416

  3. A commercial PCV2a-based vaccine significantly reduces PCV2b transmission in experimental conditions.

    PubMed

    Rose, N; Andraud, M; Bigault, L; Jestin, A; Grasland, B

    2016-07-19

    Transmission characteristics of PCV2 have been compared between vaccinated and non-vaccinated pigs in experimental conditions. Twenty-four Specific Pathogen Free (SPF) piglets, vaccinated against PCV2 at 3weeks of age (PCV2a recombinant CAP protein-based vaccine), were inoculated at 15days post-vaccination with a PCV2b inoculum (6⋅10(5) TCID50), and put in contact with 24 vaccinated SPF piglets during 42days post-inoculation. Those piglets were shared in six replicates of a contact trial involving 4 inoculated piglets mingled with 4 susceptible SPF piglets. Two replicates of a similar contact trial were made with non-vaccinated pigs. Non vaccinated animals received a placebo at vaccination time and were inoculated the same way and at the same time as the vaccinated group. All the animals were monitored twice weekly using quantitative real-time PCR and ELISA for serology until 42days post-inoculation. The frequency of infection and the PCV2 genome load in sera of the vaccinated pigs were significantly reduced compared to the non-vaccinated animals. The duration of infectiousness was significantly different between vaccinated and non-vaccinated groups (16.6days [14.7;18.4] and 26.6days [22.9;30.4] respectively). The transmission rate was also considerably decreased in vaccinated pigs (β=0.09 [0.05-0.14] compared to β=0.19 [0.11-0.32] in non-vaccinated pigs). This led to an estimated reproduction ratio of 1.5 [95% CI 0.8 - 2.2] in vaccinated animals versus 5.1 [95% CI 2.5 - 8.2] in non-vaccinated pigs when merging data of this experiment with previous trials carried out in same conditions.

  4. Polymorphisms of Serotonin Receptor 2A and 2C Genes and COMT in Relation to Obesity and Type 2 Diabetes

    PubMed Central

    Kring, Sofia I. I.; Werge, Thomas; Holst, Claus; Toubro, Søren; Astrup, Arne; Hansen, Torben; Pedersen, Oluf; Sørensen, Thorkild I. A.

    2009-01-01

    Background Candidate genes of psychological importance include 5HT2A, 5HT2C, and COMT, implicated in the serotonin, noradrenaline and dopamine pathways, which also may be involved in regulation of energy balance. We investigated the associations of single nucleotide polymorphisms (SNPs) of these genes with obesity and metabolic traits. Methodology/Principal Findings In a population of 166 200 young men examined at the draft boards, obese men (n = 726, BMI≥31.0 kg/m2) and a randomly selected group (n = 831) were re-examined at two surveys at mean ages 46 and 49 years (S-46, S-49). Anthropometric, physiological and biochemical measures were available. Logistic regression analyses were used to assess age-adjusted odds ratios. No significant associations were observed of 5HT2A rs6311, 5HT2C rs3813929 and COMT rs4680 with obesity, except that COMT rs4680 GG-genotype was associated with fat-BMI (OR = 1.08, CI = 1.01–1.16). The SNPs were associated with a number of physiological variables; most importantly 5HT2C rs3813929 T-allele was associated with glucose (OR = 4.56, CI = 1.13–18.4) and acute insulin response (OR = 0.65, CI = 0.44–0.94) in S-49. COMT rs4680 GG-genotype was associated with glucose (OR = 1.04, CI = 1.00–1.09). Except for an association between 5HT2A rs6311 and total-cholesterol at both surveys, significant in S-46 (OR = 2.66, CI = 1.11–6.40), no significant associations were observed for the other phenotypes. Significant associations were obtained when combined genotype of 5HT2C rs3813929 and COMT rs4680 were examined in relation to BMI (OR = 1.12, CI = 1.03–1.21), fat-BMI (OR = 1.22, CI = 1.08–1.38), waist (OR = 1.13, CI = 1.04–1.22), and cholesterol (OR = 5.60, CI = 0.99–31.4). Analyses of impaired glucose tolerance (IGT) and type 2 diabetes (T2D) revealed, a 12.3% increased frequency of 5HT2C rs3813929 T-allele and an 11.6% increased frequency of COMT

  5. Astrocytic GluN2A and GluN2B Oppose the Synaptotoxic Effects of Amyloid-β1-40 in Hippocampal Cells.

    PubMed

    Li, Yan; Chang, Lirong; Song, Yizhi; Gao, Xianghong; Roselli, Francesco; Liu, Jinping; Zhou, Wei; Fang, Yuan; Ling, Wei; Li, Hui; Almeida, Osborne F X; Wu, Yan

    2016-08-01

    Early-stage Alzheimer's disease (AD) is characterized by synaptic dysfunction, a phenomenon in which soluble oligomers of amyloid-beta (Aβ) and N-methyl-D-aspartate receptor (NMDAR) are implicated. Here, we demonstrated that astrocytes express NMDARs and therefore have the potential to modulate the synaptotoxic actions of Aβ. We found that specific pharmacological antagonism of two of the major NMDAR subunits, GluN2A and GluN2B, exacerbates Aβ-induced synaptotoxicity suggesting, for the first time, that astrocytic GluN2A and GluN2B mediate synaptoprotection. From the perspective of the pathogenic mechanisms of Alzheimer's disease, in which Aβ and NMDAR play significant roles, these observations are striking since neuronal GluN2A and GluN2B are well known modulators of neurodegeneration. We did initial studies to understand the basis for the differential effects of astrocytic and neuronal GluN2A and GluN2B in the promotion of synapse survival, and identified a neurotrophin produced by astrocytes, nerve growth factor β (β-NGF), as a likely mediator of the synaptoprotective effects of astrocytic GluN2A and GluN2B activation. The results presented suggest that astrocytes may be suitable druggable targets for the prevention and/or delay of the synaptic loss that occurs during early stages of AD. PMID:27497478

  6. Human UDP-glucuronosyltransferase UGT2A2: cDNA construction, expression, and functional characterization in comparison with UGT2A1 and UGT2A3

    PubMed Central

    Sneitz, Nina; Court, Michael H.; Zhang, Xiuling; Laajanen, Kaisa; Yee, Karen K.; Dalton, Pamela; Ding, Xinxin; Finel, Moshe

    2010-01-01

    Objectives Characterize the expression and glucuronidation activities of the human UDP-glucuronosyltransferase (UGT) 2A2. Methods UGT2A1 was cloned from nasal mucosa mRNA. Synthetic cDNA for UGT2A2 was constructed assuming exon sharing between UGT2A1 and UGT2A2 (Mackenzie et al., Pharmacogenetics and Genomics 2005, 15:677–685). Exon 1 of UGT2A2 was amplified from genomic DNA and combined with exons 2–6 of UGT2A1. UGT2A3 was cloned from liver mRNA. Quantitative RT-PCR was used to evaluate the expression of all the three UGTs of subfamily 2A in different tissues. Recombinant UGT2A1, UGT2A2 and UGT2A3 were expressed in baculovirus-infected insect cells and analyzed for glucuronidation activity towards different substrates. Results DNA sequencing of reverse-transcribed PCR (RT-PCR) products from human nasal mucosa mRNA, confirmed exon sharing between UGT2A1 and UGT2A2. In addition, it indicated that the N-terminal signal peptide sequence of UGT2A2 is the longest among the human UGTs. Quantitative RT-PCR revealed that both UGT2A1 and UGT2A2 are mainly expressed in the nasal mucosa, and that their expression level in fetal samples was much higher than in adults. Activity assays with recombinant UGTs 2A1–2A3 demonstrated broad substrate selectivity for UGT2A1 and UGT2A2. While glucuronidation rates and substrate affinities were mostly higher in UGT2A1, the Km values for UDP-glucuronic acid were similar in both UGTs. In addition, there were regioselectivity differences between the two UGTs and, with a few substrates, particularly ethinylestradiol, the activity of UGT2A2 was higher. Conclusions UGT2A2 is mainly expressed in the nasal mucosa and it has glucuronidation activity towards several different endo- and xenobiotic substrates. PMID:19858781

  7. 4-Bromo-2,5-dimethoxyphenethylamine (2C-B) and structurally related phenylethylamines are potent 5-HT2A receptor antagonists in Xenopus laevis oocytes

    PubMed Central

    Villalobos, Claudio A; Bull, Paulina; Sáez, Patricio; Cassels, Bruce K; Huidobro-Toro, J Pablo

    2004-01-01

    We recently described that several 2-(2,5-dimethoxy-4-substituted phenyl)ethylamines (PEAs), including 4-I=2C-I, 4-Br=2C-B, and 4-CH3=2C-D analogs, are partial agonists at 5-HT2C receptors, and show low or even negligible intrinsic efficacy at 5-HT2A receptors. These results raised the proposal that these drugs may act as 5-HT2 antagonists. To test this hypothesis, Xenopus laevis oocytes were microinjected with the rat clones for 5-HT2A or 5-HT2C receptors. The above-mentioned PEAs and its 4-H analog (2C-H) blocked the 5-HT-induced currents at 5-HT2A, but not at the 5-HT2C receptor, revealing 5-HT2 receptor subtype selectivity. The 5-HT2A receptor antagonism required a 2-min preincubation to attain maximum inhibition. All PEAs tested shifted the 5-HT concentration–response curves to the right and downward. Their potencies varied with the nature of the C(4) substituent; the relative rank order of their 5-HT2A receptor antagonist potency was 2C-I>2C-B>2C-D>2C-H. The present results demonstrate that in X. laevis oocytes, a series of 2,5-dimethoxy-4-substituted PEAs blocked the 5-HT2A but not the 5-HT2C receptor-mediated responses. As an alternative hypothesis, we suggest that the psychostimulant activity of the PEAs may not be exclusively associated with partial or full 5-HT2A receptor agonism. PMID:15006903

  8. Structural and biophysical characterization of human cytochromes P450 2B6 and 2A6 bound to volatile hydrocarbons: analysis and comparison.

    PubMed

    Shah, Manish B; Wilderman, P Ross; Liu, Jingbao; Jang, Hyun-Hee; Zhang, Qinghai; Stout, C David; Halpert, James R

    2015-04-01

    X-ray crystal structures of complexes of cytochromes CYP2B6 and CYP2A6 with the monoterpene sabinene revealed two distinct binding modes in the active sites. In CYP2B6, sabinene positioned itself with the putative oxidation site located closer to the heme iron. In contrast, sabinene was found in an alternate conformation in the more compact CYP2A6, where the larger hydrophobic side chains resulted in a significantly reduced active-site cavity. Furthermore, results from isothermal titration calorimetry indicated a much more substantial contribution of favorable enthalpy to sabinene binding to CYP2B6 as opposed to CYP2A6, consistent with the previous observations with (+)-α-pinene. Structural analysis of CYP2B6 complexes with sabinene and the structurally similar (3)-carene and comparison with previously solved structures revealed how the movement of the F206 side chain influences the volume of the binding pocket. In addition, retrospective analysis of prior structures revealed that ligands containing -Cl and -NH functional groups adopted a distinct orientation in the CYP2B active site compared with other ligands. This binding mode may reflect the formation of Cl-π or NH-π bonds with aromatic rings in the active site, which serve as important contributors to protein-ligand binding affinity and specificity. Overall, the findings from multiple techniques illustrate how drugs metabolizing CYP2B6 and CYP2A6 handle a common hydrocarbon found in the environment. The study also provides insight into the role of specific functional groups of the ligand that may influence the binding to CYP2B6.

  9. Structural and Biophysical Characterization of Human Cytochromes P450 2B6 and 2A6 Bound to Volatile Hydrocarbons: Analysis and Comparison

    PubMed Central

    Wilderman, P. Ross; Liu, Jingbao; Jang, Hyun-Hee; Zhang, Qinghai; Stout, C. David; Halpert, James R.

    2015-01-01

    X-ray crystal structures of complexes of cytochromes CYP2B6 and CYP2A6 with the monoterpene sabinene revealed two distinct binding modes in the active sites. In CYP2B6, sabinene positioned itself with the putative oxidation site located closer to the heme iron. In contrast, sabinene was found in an alternate conformation in the more compact CYP2A6, where the larger hydrophobic side chains resulted in a significantly reduced active-site cavity. Furthermore, results from isothermal titration calorimetry indicated a much more substantial contribution of favorable enthalpy to sabinene binding to CYP2B6 as opposed to CYP2A6, consistent with the previous observations with (+)-α-pinene. Structural analysis of CYP2B6 complexes with sabinene and the structurally similar (3)-carene and comparison with previously solved structures revealed how the movement of the F206 side chain influences the volume of the binding pocket. In addition, retrospective analysis of prior structures revealed that ligands containing –Cl and –NH functional groups adopted a distinct orientation in the CYP2B active site compared with other ligands. This binding mode may reflect the formation of Cl-π or NH-π bonds with aromatic rings in the active site, which serve as important contributors to protein-ligand binding affinity and specificity. Overall, the findings from multiple techniques illustrate how drugs metabolizing CYP2B6 and CYP2A6 handle a common hydrocarbon found in the environment. The study also provides insight into the role of specific functional groups of the ligand that may influence the binding to CYP2B6. PMID:25585967

  10. MicroRNA signatures predict dysregulated vitamin D receptor and calcium pathways status in limb girdle muscle dystrophies (LGMD) 2A/2B.

    PubMed

    Aguennouz, M; Lo Giudice, C; Licata, N; Rodolico, C; Musumeci, O; Fanin, M; Migliorato, A; Ragusa, M; Macaione, V; Di Giorgio, R M; Angelini, C; Toscano, A

    2016-08-01

    miRNA expression profile and predicted pathways involved in selected limb-girdle muscular dystrophy (LGMD)2A/2B patients were investigated. A total of 187 miRNAs were dysregulated in all patients, with six miRNAs showing opposite regulation in LGMD2A versus LGMD2B patients. Silico analysis evidence: (1) a cluster of the dysregulated miRNAs resulted primarily involved in inflammation and calcium metabolism, and (2) two genes predicted as controlled by calcium-assigned miRNAs (Vitamin D Receptor gene and Guanine Nucleotide Binding protein beta polypeptide 1gene) showed an evident upregulation in LGMD2B patients, in accordance with miRNA levels. Our data support alterations in calcium pathway status in LGMD 2A/B, suggesting myofibre calcium imbalance as a potential therapeutic target. Copyright © 2016 John Wiley & Sons, Ltd. PMID:27558075

  11. Different Sites of Alcohol Action in the NMDA Receptor GluN2A and GluN2B Subunits

    PubMed Central

    Zhao, Yulin; Ren, Hong; Dwyer, Donard S.; Peoples, Robert W.

    2015-01-01

    The NMDA receptor is a major target of alcohol action in the CNS, and recent behavioral and cellular studies have pointed to the importance of the GluN2B subunit in alcohol action. We and others have previously characterized four amino acid positions in the third and fourth membrane-associated (M) domains of the NMDA receptor GluN2A subunit that influence both ion channel gating and alcohol sensitivity. In this study, we found that substitution mutations at two of the four corresponding positions in the GluN2B subunit, F637 and G826, influence ethanol sensitivity and ion channel gating. Because position 826 contains a glycine residue in the native protein, we focused our attention on GluN2B(F637). Substitution mutations at GluN2B(F637) significantly altered ethanol IC50 values, glutamate EC50 values for peak (Ip) and steady-state (Iss) current, and steady-state to peak current ratios (Iss:Ip). Changes in apparent glutamate affinity were not due to agonist trapping in desensitized states, as glutamate Iss EC50 values were not correlated with Iss:Ip values. Ethanol sensitivity was correlated with values of both Ip and Iss glutamate EC50, but not with Iss:Ip. Values of ethanol IC50, glutamate EC50, and Iss:Ip for mutants at GluN2B(F637) were highly correlated with the corresponding values for mutants at GluN2A(F636), consistent with similar functional roles of this position in both subunits. These results demonstrate that GluN2B(Phe637) regulates ethanol action and ion channel function of NMDA receptors. However, despite highly conserved M domain sequences, ethanol's actions on GluN2A and GluN2B subunits differ. PMID:26051400

  12. CYP2A6 and CYP2B6 genetic variation and its association with nicotine metabolism in South Western Alaska Native people

    PubMed Central

    Binnington, Matthew J.; Zhu, Andy Z.X.; Renner, Caroline C.; Lanier, Anne P.; Hatsukami, Dorothy K.; Benowitz, Neal L; Tyndale, Rachel F.

    2012-01-01

    Objectives Alaska Native people (AN) have a high prevalence of tobacco use and associated morbidity and mortality when compared to the general U.S. population. Variation in the CYP2A6 and CYP2B6 genes, encoding enzymes responsible for nicotine metabolic inactivation and procarcinogen activation, has not been characterized in AN and may contribute to the increased risk. Methods AN people (n = 400) residing in the Bristol Bay region of South Western Alaska were recruited for a cross-sectional study on tobacco use. They were genotyped for CYP2A6*1X2A, *1X2B, *1B, *2, *4, *7, *8, *9, *10, *12, *17, *35 and CYP2B6*4, *6, *9 and provided plasma and urine samples for measurement of nicotine and metabolites. Results CYP2A6 and CYP2B6 variant frequencies among the AN Yupik people (n=361) were significantly different from other ethnicities. Nicotine metabolism (as measured by the plasma and urinary ratio of metabolites trans-3’hydroxycotinine to cotinine [(3HC/COT)] was significantly associated with CYP2A6 (P< 0.001) but not CYP2B6 genotype (P = 0.95) when controlling for known covariates. Of note, plasma 3HC/COT ratios were high in the entire Yupik people, and among the Yupik CYP2A6 wild-type participants they were substantially higher than previously characterized racial/ethnic groups (P < 0.001 vs. Caucasians and African Americans). Conclusions Yupik AN people have a unique CYP2A6 genetic profile which associated strongly with in vivo nicotine metabolism. More rapid CYP2A6-mediated nicotine and nitrosamine metabolism in the Yupik people may modulate tobacco-related disease risk. PMID:22569203

  13. GluN2A and GluN2B subunit-containing NMDA receptors in hippocampal plasticity

    PubMed Central

    Shipton, Olivia A.; Paulsen, Ole

    2014-01-01

    N-Methyl-d-aspartate receptor (NMDAR)-dependent synaptic plasticity is a strong candidate to mediate learning and memory processes that require the hippocampus. This plasticity is bidirectional, and how the same receptor can mediate opposite changes in synaptic weights remains a conundrum. It has been suggested that the NMDAR subunit composition could be involved. Specifically, one subunit composition of NMDARs would be responsible for the induction of long-term potentiation (LTP), whereas NMDARs with a different subunit composition would be engaged in the induction of long-term depression (LTD). Unfortunately, the results from studies that have investigated this hypothesis are contradictory, particularly in relation to LTD. Nevertheless, current evidence does suggest that the GluN2B subunit might be particularly important for plasticity and may make a synapse bidirectionally malleable. In particular, we conclude that the presence of GluN2B subunit-containing NMDARs at the postsynaptic density might be a necessary, though not a sufficient, condition for the strengthening of individual synapses. This is owing to the interaction of GluN2B with calcium/calmodulin-dependent protein kinase II (CaMKII) and is distinct from its contribution as an ion channel. PMID:24298164

  14. Determination of evolutionary relationships of outbreak-associated Listeria monocytogenes strains of serotypes 1/2a and 1/2b by whole-genome sequencing

    Technology Transfer Automated Retrieval System (TEKTRAN)

    We used whole-genome sequencing to determine evolutionary relationships among 20 outbreak-associated clinical isolates of Listeria monocytogenes serotypes 1/2a and 1/2b. Isolates from 6 of 11 outbreaks fell outside the clonal groups or “epidemic clones” that have been previously associated with outb...

  15. Overexpression of RelA/SpoT homologs, PpRSH2a and PpRSH2b, induces the growth suppression of the moss Physcomitrella patens.

    PubMed

    Sato, Michio; Takahashi, Tomohiro; Ochi, Kozo; Matsuura, Hideyuki; Nabeta, Kensuke; Takahashi, Kosaku

    2015-01-01

    Two genes encoding RelA/SpoT homologs, PpRSH2a and PpRSH2b, which are involved in the synthesis of bacterial alarmone guanosine 5'-diphosphate 3'-diphosphate (ppGpp) for the stringent response, were isolated from the moss, Physcomitrella patens. A complementary analysis of PpRSH2a and PpRSH2b in Escherichia coli showed that these genes had ppGpp biosynthetic activity. The recombinant PpRSH2a and PpRSH2b were also shown to synthesize ppGpp in vitro. Both proteins were localized to the chloroplasts of P. patens. Expression of the PpRSH genes was induced upon treatment with abscisic acid or abiotic stresses, such as dehydration and UV irradiation. Overexpression of PpRSH2a and PpRSH2b caused suppression of the growth in response to 1% (w/v) of glucose. The present study suggests the existence of a mechanism to regulate the growth of P. patens, which is governed by plant RSH in chloroplasts.

  16. Discrete functions of M2a and M2c macrophage subsets determine their relative efficacy in treating chronic kidney disease.

    PubMed

    Lu, Junyu; Cao, Qi; Zheng, Dong; Sun, Yan; Wang, Changqi; Yu, Xiao; Wang, Ya; Lee, Vincent W S; Zheng, Guoping; Tan, Thian K; Wang, Xin; Alexander, Stephen I; Harris, David C H; Wang, Yiping

    2013-10-01

    Two types of alternatively activated macrophages, M(2a) induced by IL-4/IL-13 and M(2c) by IL-10/TGF-β, exhibit anti-inflammatory functions in vitro and protect against renal injury in vivo. Since their relative therapeutic efficacy is unclear, we compared the effects of these two macrophage subsets in murine adriamycin nephrosis. Both subsets significantly reduced renal inflammation and renal injury; however, M(2c) macrophages more effectively reduced glomerulosclerosis, tubular atrophy, interstitial expansion, and proteinuria than M(2a) macrophages. The M(2c) macrophages were also more effective than M(2a) in reduction of macrophage and CD4(+) T-cell infiltration in kidney. Moreover, nephrotic mice treated with M(2c) had a greater reduction in renal fibrosis than those treated with M(2a). M(2c) but not M(2a) macrophages induced regulatory T cells (Tregs) from CD4(+)CD25(-) T cells in vitro, and increased Treg numbers in local draining lymph nodes of nephrotic mice. To determine whether the greater protection with M(2c) was due to their capability to induce Tregs, the Tregs were depleted by PC61 antibody in nephrotic mice treated with M(2a) or M(2c). Treg depletion diminished the superior effects of M(2c) compared to M(2a) in protection against renal injury, inflammatory infiltrates, and renal fibrosis. Thus, M(2c) are more potent than M(2a) macrophages in protecting against renal injury due to their ability to induce Tregs.

  17. CT Scans of NASA BSTRA Balls 5f5, f2, f3, sr2c, nb2a, hb2b

    SciTech Connect

    Gross, J; Thompson, R; Perry, R; Schneberk, D

    2004-01-29

    At the request of Jose Hernandez we performed some feasibility DR/CT scanning of BSTRA Balls of different sizes. To this point we have scanned all the specimens on a single system, HECAT. This particular system employs a 9 meV LINAC as the x-ray source and a THALES 12 x 16 inch 14-bit Amorphous Silicon panel as the detector. In this report we describe the system, detail some of its properties, describe the scans performed and present the data. Figure 1 contains a couple of images of the system as fielded in the 9 MeV bay. The LINAC is in the right portion of the picture. The black panels in the blue frame constitute the High Energy collimator developed specifically for High Energy DR/CT scanning (known here as Stonehenge II). The holes in the collimator panels are beveled to match the distribution of the x-rays from the LINAC, and are sized to just subtend the active area of the THALES Amorphous Silicon panel. Consequently the source to detector distance is restricted to a few positions. Nominally our source to detector distance is 6 meters. The part manipulator, part holder fixturing consists of a translate-rotate assembly on a NEWPORT air bearing table. The stages are NEWPORT RV160PP for rotation and NEWPORT IMS400CC for translation. Both are interfaced through an ESP7000 controller, which is connected to our data acquisition computer over USB. The detector holder also resides on this table and includes pitch, roll and yaw adjustments for aligning the panel to the plane of the rotational table and the x-ray beam. The relatively large source to detector distance and LINAC properties (1 mm spot size) conspire to recommend rotation-only scanning. We use a VARIAN LINATRON 3000 with the small spot retrofit implemented. We have measured the source spot size at about 1 mm. Pixel size on the THALES panel is 0.127 um. Consequently we are in a low-cone angle scanning regime which enables rotation-only 3D CT scanning of objects and assemblies with little ''cone-angle'' error.

  18. NR2A- and NR2B-containing NMDA receptors in the prelimbic medial prefrontal cortex differentially mediate trace, delay, and contextual fear conditioning.

    PubMed

    Gilmartin, Marieke R; Kwapis, Janine L; Helmstetter, Fred J

    2013-05-15

    Activation of N-methyl-D-aspartate receptors (NMDAR) in the prelimbic medial prefrontal cortex (PL mPFC) is necessary for the acquisition of both trace and contextual fear memories, but it is not known how specific NR2 subunits support each association. The NR2B subunit confers unique properties to the NMDAR and may differentially regulate these two fear memories. Here we show that NR2A-containing NMDARs mediate trace, delay, and contextual fear memories, but NR2B-containing NMDARs are required only for trace conditioning, consistent with a role for PL mPFC in working memory.

  19. Perinatal exposure to PTU delays switching from NR2B to NR2A subunits of the NMDA receptor in the rat cerebellum.

    PubMed

    Kobayashi, Kumiko; Tsuji, Ryozo; Yoshioka, Takafumi; Mino, Terumasa; Seki, Takaki

    2006-03-01

    Certain kinds of developmental neurotoxicants are considered to act by affecting the levels of thyroid hormones, which are essential for the brain development of both humans and experimental animals. Hypothyroidism experimentally induced in rats with propylthiouracil (PTU) offers a useful animal model for developmental neurotoxicity. The purpose of the present study was to clarify developmental alterations in gene expression caused by PTU in this model, with the focus on eight genes implicated in neural network formation or synaptic functions, such as the brain-derived neurotrophic factor (BDNF) and NMDA receptors 2A/2B. First, we measured the developmental profile of gene expression in vehicle-dosed rat cerebellum by quantitative RT-PCR and then examined the effects of PTU on mRNA levels on postnatal day (PND) 22, when most of the cerebellar structures in mature animals are already formed. PTU induced up-regulation of NR2B mRNA and down-regulation of NR2A and BDNF mRNAs in the cerebellum on PND 22, but there were no changes in the other genes (growth associated protein-43, L1, neuronal cell adhesion molecule, synaptophysin, post synaptic density-95). Examination of the effects of PTU on maturation of NMDAR subunits (NR2A/NR2B) demonstrated changes in relative expression on PND 14, but not on PND 4, with recovery after maturation. The profile of NMDAR subunits in vehicle-dosed rats showed a shift from NR2B to NR2A during development. These results suggest PTU can delay this switching from NR2B to NR2A subunits in the maturation of NMDA receptors.

  20. SmMYC2a and SmMYC2b played similar but irreplaceable roles in regulating the biosynthesis of tanshinones and phenolic acids in Salvia miltiorrhiza.

    PubMed

    Zhou, Yangyun; Sun, Wei; Chen, Junfeng; Tan, Hexin; Xiao, Ying; Li, Qing; Ji, Qian; Gao, Shouhong; Chen, Li; Chen, Shilin; Zhang, Lei; Chen, Wansheng

    2016-01-01

    Salvia miltiorrhiza Bunge, which contains tanshinones and phenolic acids as major classes of bioactive components, is one of the most widely used herbs in traditional Chinese medicine. Production of tanshinones and phenolic acids is enhanced by methyl jasmonate (MeJA). Transcription factor MYC2 is the switch of jasmontes signaling in plants. Here, we focused on two novel JA-inducible genes in S. miltiorrhiza, designated as SmMYC2a and SmMYC2b, which were localized in the nucleus. SmMYC2a and SmMYC2b were also discovered to interact with SmJAZ1 and SmJAZ2, implying that the two MYC2s might function as direct targets of JAZ proteins. Ectopic RNA interference (RNAi)-mediated knockdown experiments suggested that SmMYC2a/b affected multiple genes in tanshinone and phenolic acid biosynthetic pathway. Besides, the accumulation of tanshinones and phenolic acids was impaired by the loss of function in SmMYC2a/b. Meanwhile, SmMYC2a could bind with an E-box motif within SmHCT6 and SmCYP98A14 promoters, while SmMYC2b bound with an E-box motif within SmCYP98A14 promoter, through which the regulation of phenolic acid biosynthetic pathway might achieve. Together, these results suggest that SmMYC2a and SmMYC2b are JAZ-interacting transcription factors that positively regulate the biosynthesis of tanshinones and Sal B with similar but irreplaceable effects. PMID:26947390

  1. SmMYC2a and SmMYC2b played similar but irreplaceable roles in regulating the biosynthesis of tanshinones and phenolic acids in Salvia miltiorrhiza

    PubMed Central

    Zhou, Yangyun; Sun, Wei; Chen, Junfeng; Tan, Hexin; Xiao, Ying; Li, Qing; Ji, Qian; Gao, Shouhong; Chen, Li; Chen, Shilin; Zhang, Lei; Chen, Wansheng

    2016-01-01

    Salvia miltiorrhiza Bunge, which contains tanshinones and phenolic acids as major classes of bioactive components, is one of the most widely used herbs in traditional Chinese medicine. Production of tanshinones and phenolic acids is enhanced by methyl jasmonate (MeJA). Transcription factor MYC2 is the switch of jasmontes signaling in plants. Here, we focused on two novel JA-inducible genes in S. miltiorrhiza, designated as SmMYC2a and SmMYC2b, which were localized in the nucleus. SmMYC2a and SmMYC2b were also discovered to interact with SmJAZ1 and SmJAZ2, implying that the two MYC2s might function as direct targets of JAZ proteins. Ectopic RNA interference (RNAi)-mediated knockdown experiments suggested that SmMYC2a/b affected multiple genes in tanshinone and phenolic acid biosynthetic pathway. Besides, the accumulation of tanshinones and phenolic acids was impaired by the loss of function in SmMYC2a/b. Meanwhile, SmMYC2a could bind with an E-box motif within SmHCT6 and SmCYP98A14 promoters, while SmMYC2b bound with an E-box motif within SmCYP98A14 promoter, through which the regulation of phenolic acid biosynthetic pathway might achieve. Together, these results suggest that SmMYC2a and SmMYC2b are JAZ-interacting transcription factors that positively regulate the biosynthesis of tanshinones and Sal B with similar but irreplaceable effects. PMID:26947390

  2. Discovering the mechanisms underlying serotonin (5-HT)2A and 5-HT2C receptor regulation following nicotine withdrawal in rats.

    PubMed

    Zaniewska, Magdalena; Alenina, Natalia; Wydra, Karolina; Fröhler, Sebastian; Kuśmider, Maciej; McCreary, Andrew C; Chen, Wei; Bader, Michael; Filip, Małgorzata

    2015-08-01

    We have previously demonstrated that nicotine withdrawal produces depression-like behavior and that serotonin (5-HT)2A/2C receptor ligands modulate that mood-like state. In the present study we aimed to identify the mechanisms (changes in radioligand binding, transcription or RNA-editing) related to such a behavioral outcome. Rats received vehicle or nicotine (0.4 mg/kg, s.c.) for 5 days in home cages. Brain 5-HT2A/2C receptors were analyzed on day 3 of nicotine withdrawal. Nicotine withdrawal increased [(3)H]ketanserin binding to 5-HT2A receptors in the ventral tegmental area and ventral dentate gyrus, yet decreased binding in the nucleus accumbens shell. Reduction in [(3)H]mesulergine binding to 5-HT2C receptors was seen in the ventral dentate gyrus. Profound decrease in the 5-HT2A receptor transcript level was noted in the hippocampus and ventral tegmental area. Out of five 5-HT2C receptor mRNA editing sites, deep sequencing data showed a reduction in editing at the E site and a trend toward reduction at the C site in the hippocampus. In the ventral tegmental area, a reduction for the frequency of CD 5-HT2C receptor transcript was seen. These results show that the reduction in the 5-HT2A receptor transcript level may be an auto-regulatory response to the increased receptor density in the hippocampus and ventral tegmental area during nicotine withdrawal, while decreased 5-HT2C receptor mRNA editing may explain the reduction in receptor labeling in the hippocampus. Serotonin (5-HT)2A/2C receptor ligands alleviate depression-like state in nicotine-withdrawn rats. Here, we show that the reduction in 5-HT2A receptor transcript level may be an auto-regulatory response to the increased receptor number in the hippocampus and ventral tegmental area during nicotine withdrawal, while attenuated 5-HT2C receptor mRNA editing in the hippocampus might explain reduced inverse agonist binding to 5-HT2C receptor and suggest a shift toward a population of more active receptors. 5

  3. Genotype-Dependent Difference in 5-HT2C Receptor-Induced Hypolocomotion: Comparison with 5-HT2A Receptor Functional Activity

    PubMed Central

    Bazovkina, Darya V.; Kondaurova, Elena M.; Naumenko, Vladimir S.; Ponimaskin, Evgeni

    2015-01-01

    In the present study behavioral effects of the 5-HT2C serotonin receptor were investigated in different mouse strains. The 5-HT2C receptor agonist MK-212 applied intraperitoneally induced significant dose-dependent reduction of distance traveled in the open field test in CBA/Lac mice. This effect was receptor-specific because it was inhibited by the 5-HT2C receptor antagonist RS102221. To study the role of genotype in 5-HT2C receptor-induced hypolocomotion, locomotor activity of seven inbred mouse strains was measured after MK-212 acute treatment. We found that the 5-HT2C receptor stimulation by MK-212 decreased distance traveled in the open field test in CBA/Lac, C57Bl/6, C3H/He, and ICR mice, whereas it failed to affect locomotor activity in DBA/2J, Asn, and Balb/c mice. We also compared the interstrain differences in functional response to 5-HT2C and 5-HT2A receptors activation measured by the quantification of receptor-mediated head-twitches. These experiments revealed significant positive correlation between 5-HT2C and 5-HT2A receptors functional responses for all investigated mouse strains. Moreover, we found that 5-HT2A receptor activation with DOI did not change locomotor activity in CBA/Lac mice. Taken together, our data indicate the implication of 5-HT2C receptors in regulation of locomotor activity and suggest the shared mechanism for functional responses mediated by 5-HT2C and 5-HT2A receptors. PMID:26380122

  4. Genotype-Dependent Difference in 5-HT2C Receptor-Induced Hypolocomotion: Comparison with 5-HT2A Receptor Functional Activity.

    PubMed

    Bazovkina, Darya V; Kondaurova, Elena M; Naumenko, Vladimir S; Ponimaskin, Evgeni

    2015-01-01

    In the present study behavioral effects of the 5-HT2C serotonin receptor were investigated in different mouse strains. The 5-HT2C receptor agonist MK-212 applied intraperitoneally induced significant dose-dependent reduction of distance traveled in the open field test in CBA/Lac mice. This effect was receptor-specific because it was inhibited by the 5-HT2C receptor antagonist RS102221. To study the role of genotype in 5-HT2C receptor-induced hypolocomotion, locomotor activity of seven inbred mouse strains was measured after MK-212 acute treatment. We found that the 5-HT2C receptor stimulation by MK-212 decreased distance traveled in the open field test in CBA/Lac, C57Bl/6, C3H/He, and ICR mice, whereas it failed to affect locomotor activity in DBA/2J, Asn, and Balb/c mice. We also compared the interstrain differences in functional response to 5-HT2C and 5-HT2A receptors activation measured by the quantification of receptor-mediated head-twitches. These experiments revealed significant positive correlation between 5-HT2C and 5-HT2A receptors functional responses for all investigated mouse strains. Moreover, we found that 5-HT2A receptor activation with DOI did not change locomotor activity in CBA/Lac mice. Taken together, our data indicate the implication of 5-HT2C receptors in regulation of locomotor activity and suggest the shared mechanism for functional responses mediated by 5-HT2C and 5-HT2A receptors. PMID:26380122

  5. Genotype-Dependent Difference in 5-HT2C Receptor-Induced Hypolocomotion: Comparison with 5-HT2A Receptor Functional Activity.

    PubMed

    Bazovkina, Darya V; Kondaurova, Elena M; Naumenko, Vladimir S; Ponimaskin, Evgeni

    2015-01-01

    In the present study behavioral effects of the 5-HT2C serotonin receptor were investigated in different mouse strains. The 5-HT2C receptor agonist MK-212 applied intraperitoneally induced significant dose-dependent reduction of distance traveled in the open field test in CBA/Lac mice. This effect was receptor-specific because it was inhibited by the 5-HT2C receptor antagonist RS102221. To study the role of genotype in 5-HT2C receptor-induced hypolocomotion, locomotor activity of seven inbred mouse strains was measured after MK-212 acute treatment. We found that the 5-HT2C receptor stimulation by MK-212 decreased distance traveled in the open field test in CBA/Lac, C57Bl/6, C3H/He, and ICR mice, whereas it failed to affect locomotor activity in DBA/2J, Asn, and Balb/c mice. We also compared the interstrain differences in functional response to 5-HT2C and 5-HT2A receptors activation measured by the quantification of receptor-mediated head-twitches. These experiments revealed significant positive correlation between 5-HT2C and 5-HT2A receptors functional responses for all investigated mouse strains. Moreover, we found that 5-HT2A receptor activation with DOI did not change locomotor activity in CBA/Lac mice. Taken together, our data indicate the implication of 5-HT2C receptors in regulation of locomotor activity and suggest the shared mechanism for functional responses mediated by 5-HT2C and 5-HT2A receptors.

  6. Separate Fc-receptors for immunoglogulins IgG2a and IgG2b on an established cell line of mouse macrophages.

    PubMed

    Walker, W S

    1976-04-01

    The specificity of Fe-receptors on IC-21 cells, an established line of mouse peritoneal macrophages with antibody-dependent effector cell activity has been examined. Only IgG2a and IgG2b myeloma proteins bound readily to IC-21 Fc-receptors, the former in nonaggregated as well as aggregated form, the latter only as aggregated complexes. Thus, IgG2a bound in a manner characteristic of classically defined cytophilic antibody, whereas the binding of IgG2b appeared to be mediated by Fc-receptors for antigen-antibody complexes. Evidence is presented in support of the view that IC-21 macrophages possess separate and distinct Fc-receptor sites for these two immunoglobulins. PMID:1254971

  7. Neutron scattering studies of the H2a-H2b and (H3-H4)/sub 2/ histone complexes

    SciTech Connect

    Carlson, R.D.

    1982-01-01

    Neutron scattering experiments have shown that both the (H3-H4)/sub 2/ and H2a-H2b histone complexes are quite asymmetric in solution. The (H3-H4)/sub 2/ tetramer is an oblate or flattened structure, with a radius of gyration almost as large as that of the core octamer. If the tetramer is primarily globular, it must have an axial ratio of about 1:5. It is more likely, however, that this asymmetry results in part from N-terminal arms that extend outward approximately within the major plane of the particle. If this is the case, less asymmetric models for the globular part of the tetramer, including a dislocated disk, can be made consistent with the scattering data. The H2a-H2b dimer, on the other hand, is an elongated structure. 48 references, 12 figures, 1 table.

  8. Structure Change from β-Strand and Turn to α-Helix in Histone H2A-H2B Induced by DNA Damage Response.

    PubMed

    Izumi, Yudai; Fujii, Kentaro; Wien, Frank; Houée-Lévin, Chantal; Lacombe, Sandrine; Salado-Leza, Daniela; Porcel, Erika; Masoud, Rawand; Yamamoto, Satoshi; Réfrégiers, Matthieu; Hervé du Penhoat, Marie-Anne; Yokoya, Akinari

    2016-07-12

    Using synchrotron radiation-based circular dichroism spectroscopy, we found that the DNA damage response induces an increase of α-helix structure and a decrease of β-strand and turn structures in histone H2A-H2B extracted from x-irradiated human HeLa cells. The structural alterations correspond to the assumption that an average of eight amino acid residues form new α-helix structures at 310 K. We propose the structural transition from β-strand and turn structures to an α-helix structure in H2A-H2B as a novel, to our knowledge, process involved in the DNA damage response.

  9. Visible absorption spectroscopy of the B 2A1-X 2B2 transition of fluoroformyloxyl radical, FC(O)O

    NASA Astrophysics Data System (ADS)

    Maricq, M. Matti; Szente, Joseph J.; Li, Z.; Francisco, Joseph S.

    1993-01-01

    We report the visible absorption spectrum of the fluoroformyloxyl radical. The spectrum is assigned to the B 2A1-X 2B2 transition in FC(O)O. The origin of the excitation spectrum is observed at 13 150 cm-1 (760 nm). Extensive progressions in the OCO bending mode of the B state, ν'3 = 610 cm-1, dominate the spectrum. Three other progressions are observed: the OCO wag mode, ν'6 = 840 cm-1; the CF stretching mode, ν'2 = 1110 cm-1; and the asymmetric CO stretching mode, ν'4 = 2820 cm-1. Two series of hot bands also appear in the spectrum. From these bands the frequency of the OCO bending mode, ν`3 = 520 cm-1, is assigned for ground state FC(O)O. The experimental spectrum is compared to the results of ab initio MO calculations. These include second-order Møller-Plesset perturbation theory (UMP2) and quadratic configuration interactions theory with single and double excitations (QCISD) for both the X 2B2 and B 2A1 states. The origin of the B 2A1-X 2B2 transition and the predicted vibrational frequencies are found to be in reasonable agreement with experiment.

  10. Influence of synthetic and natural food dyes on activities of CYP2A6, UGT1A6, and UGT2B7.

    PubMed

    Kuno, Nayumi; Mizutani, Takaharu

    2005-08-27

    Synthetic or natural food dyes are typical xenobiotics, as are drugs and pollutants. After ingestion, part of these dyes may be absorbed and metabolized by phase I and II drug-metabolizing enzymes and excreted by transporters of phase III enzymes. However, there is little information regarding the metabolism of these dyes. It was investigated whether these dyes are substrates for CYP2A6 and UDP-glucuronosyltransferase (UGT). The in vitro inhibition of drug-metabolizing enzymes by these dyes was also examined. The synthetic food dyes studied were amaranth (food red no. 2), erythrosine B (food red no. 3), allura red (food red no. 40), new coccine (food red no. 102), acid red (food red no. 106), tartrazine (food Yellow no. 4), sunset yellow FCF (food yellow no. 5), brilliant blue FCF (food blue no. 1), and indigo carmine (food blue no. 2). The natural additive dyes studied were extracts from purple sweet potato, purple corn, cochineal, monascus, grape skin, elderberry, red beet, gardenia, and curthamus. Data confirmed that these dyes were not substrates for CYP2A6, UGT1A6, and UGT2B7. Only indigo carmine inhibited CYP2A6 in a noncompetitive manner, while erythrosine B inhibited UGT1A6 (glucuronidation of p-nitrophenol) and UGT2B7 (glucuronidation of androsterone). In the natural additive dyes just listed, only monascus inhibited UGT1A6 and UGT2B7.

  11. Histone H2A/H2B chaperones: from molecules to chromatin-based functions in plant growth and development.

    PubMed

    Zhou, Wangbin; Zhu, Yan; Dong, Aiwu; Shen, Wen-Hui

    2015-07-01

    Nucleosomal core histones (H2A, H2B, H3 and H4) must be assembled, replaced or exchanged to preserve or modify chromatin organization and function according to cellular needs. Histone chaperones escort histones, and play key functions during nucleosome assembly/disassembly and in nucleosome structure configuration. Because of their location at the periphery of nucleosome, histone H2A-H2B dimers are remarkably dynamic. Here we focus on plant histone H2A/H2B chaperones, particularly members of the NUCLEOSOME ASSEMBLY PROTEIN-1 (NAP1) and FACILITATES CHROMATIN TRANSCRIPTION (FACT) families, discussing their molecular features, properties, regulation and function. Covalent histone modifications (e.g. ubiquitination, phosphorylation, methylation, acetylation) and H2A variants (H2A.Z, H2A.X and H2A.W) are also discussed in view of their crucial importance in modulating nucleosome organization and function. We further discuss roles of NAP1 and FACT in chromatin-based processes, such as transcription, DNA replication and repair. Specific functions of NAP1 and FACT are evident when their roles are considered with respect to regulation of plant growth and development and in plant responses to environmental stresses. Future major challenges remain in order to define in more detail the overlapping and specific roles of various members of the NAP1 family as well as differences and similarities between NAP1 and FACT family members, and to identify and characterize their partners as well as new families of chaperones to understand histone variant incorporation and chromatin target specificity. PMID:25781491

  12. Histone H2A/H2B chaperones: from molecules to chromatin-based functions in plant growth and development.

    PubMed

    Zhou, Wangbin; Zhu, Yan; Dong, Aiwu; Shen, Wen-Hui

    2015-07-01

    Nucleosomal core histones (H2A, H2B, H3 and H4) must be assembled, replaced or exchanged to preserve or modify chromatin organization and function according to cellular needs. Histone chaperones escort histones, and play key functions during nucleosome assembly/disassembly and in nucleosome structure configuration. Because of their location at the periphery of nucleosome, histone H2A-H2B dimers are remarkably dynamic. Here we focus on plant histone H2A/H2B chaperones, particularly members of the NUCLEOSOME ASSEMBLY PROTEIN-1 (NAP1) and FACILITATES CHROMATIN TRANSCRIPTION (FACT) families, discussing their molecular features, properties, regulation and function. Covalent histone modifications (e.g. ubiquitination, phosphorylation, methylation, acetylation) and H2A variants (H2A.Z, H2A.X and H2A.W) are also discussed in view of their crucial importance in modulating nucleosome organization and function. We further discuss roles of NAP1 and FACT in chromatin-based processes, such as transcription, DNA replication and repair. Specific functions of NAP1 and FACT are evident when their roles are considered with respect to regulation of plant growth and development and in plant responses to environmental stresses. Future major challenges remain in order to define in more detail the overlapping and specific roles of various members of the NAP1 family as well as differences and similarities between NAP1 and FACT family members, and to identify and characterize their partners as well as new families of chaperones to understand histone variant incorporation and chromatin target specificity.

  13. A 2A2<--X 2B1 absorption and Raman spectra of the OClO molecule: A three-dimensional time-dependent wave packet study

    NASA Astrophysics Data System (ADS)

    Sun, Zhigang; Lou, Nanquan; Nyman, Gunnar

    2005-02-01

    Time-dependent wave packet calculations of the (A 2A2←X 2B1) absorption and Raman spectra of the OClO molecule are reported. The Fourier grid Hamiltonian method in three dimensions is employed. The X 2B1 ground state ab initio potential energy surface reported by Peterson [J. Chem. Phys. 109, 8864 (1998)] is used together with his corresponding A 2A2 state surface or the revised surface of the A 2A2 state by Xie and Guo [Chem. Phys. Lett. 307, 109 (1999)]. Radau coordinates are used to describe the vibrations of a nonrotating OClO molecule. The split-operator method combined with fast Fourier transform is applied to propagate the wave function. We find that the ab initio A 2A2 potential energy surface better reproduces the detailed structures of the absorption spectrum at long wavelength, while the revised surface of the A 2A2 state, consistent with the work of Xie and Guo, better reproduces the overall shape and the energies of the vibrational levels. Both surfaces of the A 2A2 state can reasonably reproduce the experimental Raman spectra but neither does so in detail for the numerical model employed in the present work.

  14. Differences in intensity and specificity of hypersensitive response induction in Nicotiana spp. by INF1, INF2A, and INF2B of Phytophthora infestans.

    PubMed

    Huitema, Edgar; Vleeshouwers, Vivianne G A A; Cakir, Cahit; Kamoun, Sophien; Govers, Francine

    2005-03-01

    Elicitins form a family of structurally related proteins that induce the hypersensitive response (HR) in plants, particularly Nicotiana spp. The elicitin family is composed of several classes. Most species of the plant-pathogenic oomycete genus Phytophthora produce the well-characterized 10-kDa canonical elicitins (class I), such as INF1 of the potato and tomato pathogen Phytophthora infestans. Two genes, inf2A and inf2B, encoding a distinct class (class III) of elicitin-like proteins, also occur in P. infestans. Unlike secreted class I elicitins, class III elicitins are thought to be cell-surface-anchored polypeptides. Molecular characterization of the inf2 genes indicated that they are widespread in Phytophthora spp. and occur as a small gene family. In addition, Southern blot and Northern blot hybridizations using gene-specific probes showed that inf2A and inf2B genes and transcripts can be detected in 17 different P. infestans isolates. Functional secreted expression in plant cells of the elicitin domain of the infl and inf2 genes was conducted using a binary Potato virus X (PVX) vector (agroinfection) and Agrobacterium tumefaciens transient transformation assays (agroinfiltration), and resulted in HR-like necrotic symptoms and induction of defense response genes in tobacco. However, comparative analyses of elicitor activity of INF1, INF2A, and INF2B revealed significant differences in intensity, specificity, and consistency of HR induction. Whereas INF1 induced the HR in Nicotiana benthamiana, INF2A induced weak symptoms and INF2B induced no symptoms on this plant. Nonetheless, similar to INF1, HR induction by INF2A in N. benthamiana required the ubiquitin ligase-associated protein SGT1. Overall, these results suggest that variation in the resistance of Nicotiana spp. to P. infestans is shadowed by variation in the response to INF elicitins. The ability of tobacco, but not N. benthamiana, to respond to INF2B could explain differences in resistance to P

  15. First detection of canine parvovirus type 2c in Brazil

    PubMed Central

    Streck, André Felipe; de Souza, Carine Kunzler; Gonçalves, Karla Rathje; Zang, Luciana; Pinto, Luciane Dubina; Canal, Cláudio Wageck

    2009-01-01

    The presence of canine parvovirus type 2 (CPV-2), 2a and 2b has been described in Brazil, however, the type 2c had not been reported until now. In the current study, seven out of nine samples from dogs with diarrhea were characterized as CPV-2c, indicating that this virus is already circulating in the Brazilian canine population. PMID:24031389

  16. NMDA receptor GluN2A/GluN2B subunit ratio as synaptic trait of levodopa-induced dyskinesias: from experimental models to patients

    PubMed Central

    Mellone, Manuela; Stanic, Jennifer; Hernandez, Ledia F.; Iglesias, Elena; Zianni, Elisa; Longhi, Annalisa; Prigent, Annick; Picconi, Barbara; Calabresi, Paolo; Hirsch, Etienne C.; Obeso, Jose A.; Di Luca, Monica; Gardoni, Fabrizio

    2015-01-01

    Levodopa-induced dyskinesias (LIDs) are major complications in the pharmacological management of Parkinson’s disease (PD). Abnormal glutamatergic transmission in the striatum is considered a key factor in the development of LIDs. This work aims at: (i) characterizing N-methyl-D-aspartate (NMDA) receptor GluN2A/GluN2B subunit ratio as a common synaptic trait in rat and primate models of LIDs as well as in dyskinetic PD patients; and (ii) validating the potential therapeutic effect of a cell-permeable peptide (CPP) interfering with GluN2A synaptic localization on the dyskinetic behavior of these experimental models of LIDs. Here we demonstrate an altered ratio of synaptic GluN2A/GluN2B-containing NMDA receptors in the striatum of levodopa-treated dyskinetic rats and monkeys as well as in post-mortem tissue from dyskinetic PD patients. The modulation of synaptic NMDA receptor composition by a cell-permeable peptide interfering with GluN2A subunit interaction with the scaffolding protein postsynaptic density protein 95 (PSD-95) leads to a reduction in the dyskinetic motor behavior in the two animal models of LIDs. Our results indicate that targeting synaptic NMDA receptor subunit composition may represent an intriguing therapeutic approach aimed at ameliorating levodopa motor side effects. PMID:26217176

  17. A comparison of the behavioural effects of 5-HT2A and 5-HT2C receptor agonists in the pigeon.

    PubMed

    Wolff, M C; Leander, J D

    2000-08-01

    Activity at the 5-HT2A receptor versus that of the 5-HT2C receptor was studied in three behavioural paradigms. In pigeons trained to discriminate 0.32 mg/kg of 1-(2,5-diemethoxy-4-iodophenyl)-2-aminopropane (DOI) (a mixed 5-HT2A/C receptor agonist) from vehicle, quipazine (0.1-1 mg/kg) and m-chlorophenylpiperazine (mCPP) (1-3 mg/kg) substituted for DOI in a dose-related manner, and this generalization was blocked by MDL100907 (0.0001-0.01 mg/kg), a selective 5-HT2A receptor antagonist. RO60-0175 (a relatively selective 5-HT2C agonist) induced partial substitution at 3 mg/kg that was antagonized by both MDL100907 and by 3 mg/kg of SB242084, a relatively selective 5-HT2C antagonist. MK212 (a mixed 5-HT2C/A agonist) induced partial substitution that was antagonized by SB242084, but not by MDL100907. On a progressive ratio 5 operant schedule (PR5) for food reinforcement, DOI, quipazine, mCPP, MK212 and R060-0175 decreased the break point; mCPP, DOI, MK212 and quipazine also induced vomiting. Although MDL100907 antagonized both the reductions of break point and vomiting, SB242084 only partially attenuated the decrease in break point observed with MK212 and DOI, and was unable to eliminate vomiting. Thus pharmacological activity at the 5-HT2A receptor can be behaviourally distinguished from pharmacological activity at the 5-HT2C receptor in the pigeon. Furthermore, the decrease in the break point of a PR5 schedule induced by 5-HT2C receptor agonists may be related to decreased appetite, whereas that induced by 5-HT2A receptor agonists may be due to unrelated factors, such as emesis. PMID:11103887

  18. Association of FCGR2A p.R131H and CCL2 c.-2518 A>G gene variants with thrombocytopenia in patients with dengue virus infection.

    PubMed

    Alagarasu, Kalichamy; Bachal, Rupali V; Damle, Indraneel; Shah, Paresh S; Cecilia, Dayaraj

    2015-11-01

    FCGR2A and CCL2 gene variants are important in dengue pathogenesis and were investigated in 122 dengue patients (DENs) [89 dengue fever (DF) and 33 dengue hemorrhagic fever (DHF)] and 107 healthy controls (HCs) to find out their association with severity of dengue. Genotype frequencies of FCGR2A p.R131H and CCL2 c.-2518 A > G polymorphisms were not different between DF, DHF and HC. Significantly higher frequency of R/R genotype of FCGR2A p.R131H was observed in DEN cases with thrombocytopenia (TP) while the G/G genotype of CCL2 c.-2518 A > G was observed only in DEN cases with TP (p < 0.005). These results suggest that FCGR2A and CCL2 gene variants were associated with the risk of TP in dengue infections.

  19. Adenosine A(1), A(2a), A(2b), and A(3) receptors in hematopoiesis. 1. Expression of receptor mRNA in four mouse hematopoietic precursor cells.

    PubMed

    Streitová, D; Sefc, L; Savvulidi, F; Pospísil, M; Holá, J; Hofer, M

    2010-01-01

    Four mouse bone marrow or thymus cell populations, namely granulopoietic/monocytopoietic, erythropoietic, B-lymphopoietic, and T-lymphopoietic precursor cells have been assayed by RT-PCR technique for the presence and relative amounts of adenosine A(1), A(2a), A(2b), and A(3) receptor mRNA. It has been found that (i) all four populations studied express all four adenosine receptor subtypes, (ii) the A(1), receptor is the least expressed in all populations studied, (iii) the A(3) receptor is markedly expressed in the populations of granulopoietic/monocytopoietic and erythropoietic cells, (iv) the A(2a) receptor is markedly expressed in the populations of B-lymphopoietic and T-lymphopoietic cells, and v) the A(2b) receptor does not predominate in any of the precursor cells studied. Our data offer a new possibility for the assessment of the readiness of these cells to respond, by receptor-mediated mechanisms, to adenosine or its analogs present in the tissues as a result of endogenous processes and/or following their administration.

  20. Functional selectivity of hallucinogenic phenethylamine and phenylisopropylamine derivatives at human 5-hydroxytryptamine (5-HT)2A and 5-HT2C receptors.

    PubMed

    Moya, Pablo R; Berg, Kelly A; Gutiérrez-Hernandez, Manuel A; Sáez-Briones, Patricio; Reyes-Parada, Miguel; Cassels, Bruce K; Clarke, William P

    2007-06-01

    2,5-Dimethoxy-4-substituted phenylisopropylamines and phenethylamines are 5-hydroxytryptamine (serotonin) (5-HT)(2A/2C) agonists. The former are partial to full agonists, whereas the latter are partial to weak agonists. However, most data come from studies analyzing phospholipase C (PLC)-mediated responses, although additional effectors [e.g., phospholipase A(2) (PLA(2))] are associated with these receptors. We compared two homologous series of phenylisopropylamines and phenethylamines measuring both PLA(2) and PLC responses in Chinese hamster ovary-K1 cells expressing human 5-HT(2A) or 5-HT(2C) receptors. In addition, we assayed both groups of compounds as head shake inducers in rats. At the 5-HT(2C) receptor, most compounds were partial agonists for both pathways. Relative efficacy of some phenylisopropylamines was higher for both responses compared with their phenethylamine counterparts, whereas for others, no differences were found. At the 5-HT(2A) receptor, most compounds behaved as partial agonists, but unlike findings at 5-HT(2C) receptors, all phenylisopropylamines were more efficacious than their phenethylamine counterparts. 2,5-Dimethoxyphenylisopropylamine activated only the PLC pathway at both receptor subtypes, 2,5-dimethoxyphenethylamine was selective for PLC at the 5-HT(2C) receptor, and 2,5-dimethoxy-4-nitrophenethylamine was PLA(2)-specific at the 5-HT(2A) receptor. For both receptors, the rank order of efficacy of compounds differed depending upon which response was measured. The phenylisopropylamines were strong head shake inducers, whereas their phenethylamine congeners were not, in agreement with in vitro results and the involvement of 5-HT(2A) receptors in the head shake response. Our results support the concept of functional selectivity and indicate that subtle changes in ligand structure can result in significant differences in the cellular signaling profile.

  1. A translation system reconstituted with human factors proves that processing of encephalomyocarditis virus proteins 2A and 2B occurs in the elongation phase of translation without eukaryotic release factors.

    PubMed

    Machida, Kodai; Mikami, Satoshi; Masutani, Mamiko; Mishima, Kurumi; Kobayashi, Tominari; Imataka, Hiroaki

    2014-11-14

    The genomic RNA of encephalomyocarditis virus (EMCV) encodes a single polyprotein, and the primary scission of the polyprotein occurs between nonstructural proteins 2A and 2B by an unknown mechanism. To gain insight into the mechanism of 2A-2B processing, we first translated the 2A-2B region in vitro with eukaryotic and prokaryotic translation systems. The 2A-2B processing occurred only in the eukaryotic systems, not in the prokaryotic systems, and the unprocessed 2A-2B protein synthesized by a prokaryotic system remained uncleaved when incubated with a eukaryotic cell extract. These results suggest that 2A-2B processing is a eukaryote-specific, co-translational event. To define the translation factors required for 2A-2B processing, we constituted a protein synthesis system with eukaryotic elongation factors 1 and 2, eukaryotic release factors 1 and 3 (eRF1 and eRF3), aminoacyl-tRNA synthetases, tRNAs, ribosome subunits, and a plasmid template that included the hepatitis C virus internal ribosome entry site. We successfully reproduced 2A-2B processing in the reconstituted system even without eRFs. Our results indicate that this unusual event occurs in the elongation phase of translation.

  2. The role of the 5-HT2A and 5-HT2C receptors in the stimulus effects of hallucinogenic drugs. I: Antagonist correlation analysis.

    PubMed

    Fiorella, D; Rabin, R A; Winter, J C

    1995-10-01

    Investigations conducted over the past 3 decades have demonstrated that serotonergic receptors, specifically the 5-HT2A and 5-HT2C subtypes, play an important role in the behavioral effects of hallucinogenic compounds. The present study was designed to determine the respective significance of these two receptors in the stimulus effects of LSD and (-)DOM in the rat. Specifically, the interactions of a series of serotonergic antagonists (risperidone, pirenpirone, metergoline, ketanserin, loxapine, LY53857, pizotyline, spiperone, cyprohepatadine, mesulergine, promethazine, and thioridazine) with the LSD stimulus and the (-)DOM stimulus in LSD-trained subjects was defined. From these data, IC50 values were determined for the inhibition of the LSD-appropriate responding elicited by either 0.1 mg/kg LSD (15-min pretreatment time) or 0.4 mg/kg (-)DOM (75-min pretreatment). In addition, the affinities of these antagonists for 5-HT2A and 5-HT2C receptors were determined in radioligand competition studies, 5-HT2A affinity correlated significantly with IC50 values for the blockade of the LSD (r = +0.75, P < 0.05) and (-)DOM (r = +0.95, P < 0.001) stimuli in the LSD trained subjects. 5-HT2C affinity did not correlate significantly with either series of IC50 values. These data indicate that (1) the stimulus effects of LSD, and (2) the substitution of (-)DOM for the LSD stimulus are mediated by agonist activity at 5-HT2A receptors.

  3. Bioactive substance from Grifola frondosa (maitake) mushroom inhibits CCAAT enhancer binding protein beta and delta expression on C3H10T1/2 B2C1 adipocyte cells.

    PubMed

    Minamino, Katsuhiko; Yanaga, Yuri; Ohtsuru, Masaru

    2008-06-01

    Bioactive compound substances from Grifola frondosa (maitake) inhibited adipocyte differentiation of B(2)C(1) preadipocytes. This compound is not related to MAP kinase (ERK1 and ERK2) cascades or beta-catenin, which inhibit the expression of Glut4, PPARgamma and C/EBPalpha. The compound reduced the expression time of C/EBPbeta and C/EBPdelta. These results suggest that the inhibitory action of these bioactive compounds on adipocyte differentiation is exhibited through preadipocytes. They cannot induce the expression of PPARgamma or C/EBPalpha because of the reduced expression time of C/EBPbeta and C/EBPdelta. PMID:18635913

  4. Synthesis and in vitro evaluation of [18F]FECIMBI-36: A potential agonist PET ligand for 5-HT2A/2C receptors

    PubMed Central

    Prabhakaran, Jaya; Underwood, Mark D.; Dileep Kumar, J. S.; Simpson, Norman R.; Kassir, Suham A.; Bakalian, Mihran J.; Mann, J. John; Arango, Victoria

    2016-01-01

    Radiosynthesis and in vitro evaluation of [18F]-2-(4-bromo-2,5-dimethoxyphenyl)-N-(2-(2-fluoroethoxy)benzyl)ethanamine, ([18F]FECIMBI-36) or ([18F]1), a potential agonist PET imaging agent for 5-HT2A/2C receptors is described. Syntheses of reference standard 1 and the corresponding des-fluoroethyl radiolabeling precursor (2) were achieved with 75% and 65% yields, respectively. In vitro pharmacology assay of FECIMBI-36 by [3H]-ketanserin competition binding assay obtained from NIMH-PDSP showed high affinities to 5-HT2AR (Ki = 1 nM) and 5-HT2CR (Ki = 1.7 nM). Radiolabeling of FECIMBI-36 was achieved from the boc-protected precursor 2 using [18F]-fluoroethyltosylate in presence of Cs2CO3 in DMSO followed by removal of the protective group. [18F]1 was isolated using RP-HPLC in 25 ± 5% yield, purity ≥95% and specific activity 1–2 Ci/μmol (N = 6). In vitro autoradiography studies demonstrate that [18F]1 selectively label 5-HT2A and 5-HT2C receptors in slide-mounted sections of postmortem human brain using phosphor imaging. Our results indicate the potential of [18F]1 for imaging 5-HT2A/2C receptors in the high affinity state in vivo using PET imaging. PMID:26253634

  5. Synthesis and in vitro evaluation of [18F]FECIMBI-36: A potential agonist PET ligand for 5-HT2A/2C receptors.

    PubMed

    Prabhakaran, Jaya; Underwood, Mark D; Kumar, J S Dileep; Simpson, Norman R; Kassir, Suham A; Bakalian, Mihran J; Mann, J John; Arango, Victoria

    2015-09-15

    Radiosynthesis and in vitro evaluation of [(18)F]-2-(4-bromo-2,5-dimethoxyphenyl)-N-(2-(2-fluoroethoxy)benzyl)ethanamine, ([(18)F]FECIMBI-36) or ([(18)F]1), a potential agonist PET imaging agent for 5-HT2A/2C receptors is described. Syntheses of reference standard 1 and the corresponding des-fluoroethyl radiolabeling precursor (2) were achieved with 75% and 65% yields, respectively. In vitro pharmacology assay of FECIMBI-36 by [(3)H]-ketanserin competition binding assay obtained from NIMH-PDSP showed high affinities to 5-HT2AR (Ki = 1nM) and 5-HT2CR (Ki=1.7 nM). Radiolabeling of FECIMBI-36 was achieved from the boc-protected precursor 2 using [(18)F]-fluoroethyltosylate in presence of Cs2CO3 in DMSO followed by removal of the protective group. [(18)F]1 was isolated using RP-HPLC in 25 ± 5% yield, purity > 95% and specific activity 1-2Ci/μmol (N = 6). In vitro autoradiography studies demonstrate that [(18)F]1 selectively label 5-HT2A and 5-HT2C receptors in slide-mounted sections of postmortem human brain using phosphor imaging. Our results indicate the potential of [(18)F]1 for imaging 5-HT2A/2C receptors in the high affinity state in vivo using PET imaging.

  6. Probing the 2B2-2A1 conically intersecting electronic states of ClO2 through photodetachment spectroscopy of its negative ion

    NASA Astrophysics Data System (ADS)

    Krishnan, Gireesh M.; Mahapatra, Susanta

    2003-05-01

    The photodetachment spectroscopy of the ClO2- ion is studied theoretically with the aid of a time-dependent wave packet method. The theoretical findings in conjunction with the experimental observations unambiguously established the existence of a conical intersection in the excited 2B2-2A1 electronic manifold of ClO2. The highly diffused vibrational structure of this electronic manifold observed in the experimental recording is attributed to the nonadiabatic effects associated with this conical intersection. In our study we employed the near-equilibrium potential energy surfaces reported by Peterson and Werner [J. Chem. Phys. 96, 8948 (1992)] along the symmetric stretching and bending vibrations of ClO2. The potential energy surfaces along the asymmetric stretching vibration are assumed to be harmonic. The dynamics of the system is studied within a linear vibronic coupling scheme, and the strength of the coupling is explicitly determined by ab initio methods. The effect of the next higher 2A2 electronic state of ClO2 on the above photoelectron band is also discussed. The nonradiative decay dynamics of the system mediated by the vibronic coupling is examined, and the findings are correlated with the femtosecond time-resolved experiment.

  7. 76 FR 60518 - Notice of Discontinuation of H-2A and H-2B Temporary Worker Visa Exit Program Pilot CBP Dec. 11-16

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-29

    ... Worker Visa Exit Program Pilot until December 8, 2009. 74 FR 42909. The pilot has been operating for more... temporary workers at certain designated ports of entry effective August 1, 2009.\\1\\ 73 FR 77049. \\1\\ The H... Pilot to Include H-2B Temporary Workers.'' 73 FR 77817.\\2\\ \\2\\ The H-2B nonimmigrant...

  8. Bulk and mechanical properties of the Paintbrush tuff recovered from boreholes UE25 NRG-2, 2A, 2B, and 3: Data report

    SciTech Connect

    Boyd, P.J.; Martin, R.J.; Noel, J.S.; Price, R.H.

    1996-09-01

    An integral part of the licensing procedure for the potential nuclear waste repository at Yucca Mountain, Nevada, involves characterization of the in situ rheology for the design and construction of the facility and the emplacement of canisters containing radioactive waste. The data used to model the thermal and mechanical behavior of the repository and surrounding lithologies include dry and saturated bulk densities, average grain density, porosity, compressional and shear wave velocities, elastic moduli, and compressional and tensional fracture strengths. In this study, a suite of experiments was performed on cores recovered from boreholes UE25 NRG-2, 2A, 2B, and 3 drilled in support of the Exploratory Studies Facility (ESF) at Yucca Mountain. The holes penetrated the Timber Mountain tuff and two thermal/mechanical units of the Paintbrush tuff. The thermal/mechanical stratigraphy was defined by Ortiz to group rock horizons of similar properties for the purpose of simplifying modeling efforts. The relationship between the geologic stratigraphy and the thermal/mechanical stratigraphy for each borehole is presented. The tuff samples in this study have a wide range of welding characteristics (usually reflected in sample porosity), and a smaller range of mineralogy and petrology characteristics. Generally, the samples are silicic, ash-fall tuffs that exhibit large variability in their elastic and strength properties.

  9. Intrahippocampal Administration of Ibotenic Acid Induced Cholinergic Dysfunction via NR2A/NR2B Expression: Implications of Resveratrol against Alzheimer Disease Pathophysiology

    PubMed Central

    Karthick, Chennakesavan; Periyasamy, Sabapathy; Jayachandran, Kesavan S.; Anusuyadevi, Muthuswamy

    2016-01-01

    Although several drugs revealed moderate amelioration of symptoms, none of them have sufficient potency to prevent or reverse the progression toward Alzheimer's disease (AD) pathology. Resveratrol (RSV), a polyphenolic compound has shown an outstanding therapeutic effect on a broad spectrum of diseases like age-associated neurodegeneration, inflammation etc. The present study was thus conducted to assess the therapeutic efficacy of RSV in ameliorating the deleterious effects of Ibotenic acid (IBO) in male Wistar rats. Stereotactic intrahippocampal administration of IBO (5 μg/μl) lesioned rats impairs cholinergic transmission, learning and memory performance that is rather related to AD and thus chosen as a suitable model to understand the drug efficacy in preventing AD pathophysiology. Since IBO is an agonist of glutamate, it is expected to exhibit an excitotoxic effect by altering glutamatergic receptors like NMDA receptor. The current study displayed significant alterations in the mRNA expression of NR2A and NR2B subunits of NMDA receptors, and further it is surprising to note that cholinergic receptors decreased in expression particularly α7-nAChR with increased m1AChR. RSV administration (20 mg/kg body weight, i.p.) significantly reduced these changes in IBO induced rats. Glutamatergic and cholinergic receptor alterations were associated with significant changes in the behavioral parameters of rats induced by IBO. While RSV improved spatial learning performance, attenuated immobility, and improvised open field activity in IBO induced rats. NR2B activation in the present study might mediate cell death through oxidative stress that form the basis of abnormal behavioral pattern in IBO induced rats. Interestingly, RSV that could efficiently encounter oxidative stress have significantly decreased stress markers viz., nitrite, PCO, and MDA levels by enhancing antioxidant status. Histopathological analysis displayed significant reduction in the hippocampal

  10. Determination of Evolutionary Relationships of Outbreak-Associated Listeria monocytogenes Strains of Serotypes 1/2a and 1/2b by Whole-Genome Sequencing

    PubMed Central

    Bergholz, Teresa M.; den Bakker, Henk C.; Katz, Lee S.; Silk, Benjamin J.; Jackson, Kelly A.; Kucerova, Zuzana; Joseph, Lavin A.; Turnsek, Maryann; Gladney, Lori M.; Halpin, Jessica L.; Xavier, Karen; Gossack, Joseph; Ward, Todd J.; Frace, Michael

    2015-01-01

    We used whole-genome sequencing to determine evolutionary relationships among 20 outbreak-associated clinical isolates of Listeria monocytogenes serotypes 1/2a and 1/2b. Isolates from 6 of 11 outbreaks fell outside the clonal groups or “epidemic clones” that have been previously associated with outbreaks, suggesting that epidemic potential may be widespread in L. monocytogenes and is not limited to the recognized epidemic clones. Pairwise comparisons between epidemiologically related isolates within clonal complexes showed that genome-level variation differed by 2 orders of magnitude between different comparisons, and the distribution of point mutations (core versus accessory genome) also varied. In addition, genetic divergence between one closely related pair of isolates from a single outbreak was driven primarily by changes in phage regions. The evolutionary analysis showed that the changes could be attributed to horizontal gene transfer; members of the diverse bacterial community found in the production facility could have served as the source of novel genetic material at some point in the production chain. The results raise the question of how to best utilize information contained within the accessory genome in outbreak investigations. The full magnitude and complexity of genetic changes revealed by genome sequencing could not be discerned from traditional subtyping methods, and the results demonstrate the challenges of interpreting genetic variation among isolates recovered from a single outbreak. Epidemiological information remains critical for proper interpretation of nucleotide and structural diversity among isolates recovered during outbreaks and will remain so until we understand more about how various population histories influence genetic variation. PMID:26590286

  11. Multiple conformations of 5-HT2A and 5-HT 2C receptors in rat brain: an autoradiographic study with [125I](±)DOI.

    PubMed

    López-Giménez, Juan F; Vilaró, M Teresa; Palacios, José M; Mengod, Guadalupe

    2013-10-01

    Earlier autoradiographic studies with the 5-HT2 receptor agonist [(125)I](±)DOI in human brain showed unexpected biphasic competition curves for various 5-HT2A antagonists. We have performed similar studies in rat brain regions with selective 5-HT2A (M100907) and 5-HT2C (SB242084) antagonists together with ketanserin and mesulergine. The effect of GTP analogues on antagonist competition was also studied. Increasing concentrations of Gpp(NH)p or GTPγS resulted in a maximal inhibition of [(125)I](±)DOI-specific binding of approximately 50 %. M100907 competed biphasically in all regions. In the presence of 100 μM Gpp(NH)p, M100907 still displaced biphasically the remaining [(125)I](±)DOI binding. Ketanserin showed biphasic curves in some regions and monophasic curves in others. In the latter, Gpp(NH)p evidenced an additional high-affinity site. SB242084 competed biphasically in brainstem nuclei and monophasically in the other regions. In most areas, SB242084 affinities were not notably altered by Gpp(NH)p. Mesulergine competed monophasically in all regions without alteration by Gpp(NH)p. These results conform with the extended ternary complex model of receptor action: receptor exists as an equilibrium of multiple conformations, i.e. ground (R), partly activated (R*) and activated G-protein-coupled (R*G) conformation/s. Thus, [(125)I](±)DOI would label multiple conformations of both 5-HT2A and 5-HT2C receptors in rat brain, and M100907 and ketanserin would recognise these conformations with different affinities.

  12. Phenylephrine preconditioning in embryonic heart H9c2 cells is mediated by up-regulation of SUR2B/Kir6.2: A first evidence for functional role of SUR2B in sarcolemmal KATP channels and cardioprotection.

    PubMed

    Jovanović, Sofija; Ballantyne, Thomas; Du, Qingyou; Blagojević, Miloš; Jovanović, Aleksandar

    2016-01-01

    ATP-sensitive K(+) (KATP) channels were originally described in cardiomyocytes, where physiological levels of intracellular ATP keep them in a closed state. Structurally, these channels are composed of pore-forming inward rectifier, Kir6.1 or Kir6.2, and a regulatory, ATP-binding subunit, SUR1, SUR2A or SUR2B. SUR1 and Kir6.2 form pancreatic type of KATP channels, SUR2A and Kir6.2 form cardiac type of KATP channels, SUR2B and Kir6.1 form vascular smooth muscle type of KATP channels. The presence of SUR2B has been described in cardiomyocytes, but its functional significance and role has remained unknown. Pretreatment with phenylephrine (100nM) for 24h increased mRNA levels of SUR2B and Kir6.2, without affecting those levels of SUR1, SUR2A and Kir6.1 in embryonic heart H9c2 cells. Such increase was associated with increased K(+) current through KATP channels and Kir6.2/SUR2B protein complexes as revealed by whole cell patch clamp electrophysiology and immunoprecipitation/Western blotting respectively. Pretreatment with phenylephrine (100nM) generated a cellular phenotype that acquired resistance to chemical hypoxia induced by 2,4-dinitrophenol (DNP; 10mM), which was accompanied by increased in K(+) current in response to DNP (10mM). Cytoprotection afforded by phenylephrine (100nM) was abolished by infection of H9c2 cells with adenovirus containing Kir6.2AFA, a mutant form of Kir6.2 with largely reduced K(+) conductance. Taking all together, the present findings demonstrate that the activation of α1-adrenoceptors up-regulates SUR2B/Kir6.2 to confer cardioprotection. This is the first account of possible physiological role of SUR2B in cardiomyocytes.

  13. NR2A- and NR2B-Containing NMDA Receptors in the Prelimbic Medial Prefrontal Cortex Differentially Mediate Trace, Delay, and Contextual Fear Conditioning

    ERIC Educational Resources Information Center

    Gilmartin, Marieke R.; Kwapis, Janine L.; Helmstetter, Fred J.

    2013-01-01

    Activation of "N"-methyl-D-aspartate receptors (NMDAR) in the prelimbic medial prefrontal cortex (PL mPFC) is necessary for the acquisition of both trace and contextual fear memories, but it is not known how specific NR2 subunits support each association. The NR2B subunit confers unique properties to the NMDAR and may differentially…

  14. The influence of 5-HT(2A) activity on a 5-HT(2C) specific in vivo assay used for early identification of multiple acting SERT and 5-HT(2C) receptor ligands.

    PubMed

    Éliás, Olivér; Nógrádi, Katalin; Domány, György; Szakács, Zoltán; Kóti, János; Szántay, Csaba; Tarcsay, Ákos; Keserű, György M; Gere, Anikó; Kiss, Béla; Kurkó, Dalma; Kolok, Sándor; Némethy, Zsolt; Kapui, Zoltán; Hellinger, Éva; Vastag, Mónika; Sághy, Katalin; Kedves, Rita; Gyertyán, István

    2016-02-01

    As a result of our exploratory programme aimed at elaborating dually acting compounds towards the serotonin (5-HT) transporter (SERT) and the 5-HT2C receptor a novel series of 3-amino-1-phenylpropoxy substituted diphenylureas was identified. From that collection two promising compounds (2 and 3) exhibiting highest 5-HT2C receptor affinity strongly inhibited the 5-HT2C receptor agonist 1-(3-chlorophenyl)piperazine (mCPP) induced hypomotility in mice. In further pursuance of that objective (2-aminoethyl)(benzyl)sulfamoyl diphenylureas and diphenylpiperazines have also been elaborated. Herein we report the synthesis of potent multiple-acting compounds from this new class. However, when two optimized representatives (6 and 14) possessing the desired in vitro profile were tested neither reduced the motor activity of mCPP treated animals. Comparative albeit limited in vitro structure-activity relationship (SAR) analysis and detailed in vivo studies are discussed and explanation for their intricate behaviour is proposed.

  15. NMDA GluN2A and GluN2B receptors play separate roles in the induction of LTP and LTD in the amygdala and in the acquisition and extinction of conditioned fear.

    PubMed

    Dalton, Gemma L; Wu, Dong Chuan; Wang, Yu Tian; Floresco, Stan B; Phillips, Anthony G

    2012-02-01

    Synaptic plasticity mediated by NMDA glutamate receptors is thought to be a primary mechanism underlying the formation of new memories. Activation of GluN2A NMDA receptor subunits may induce long-term potentiation (LTP), whereas low-frequency stimulation of GluN2B receptors induces long-term depression (LTD). In the present study, we show that blockade of GluN2A, but not GluN2B receptors with NVP-AAM077 and Ro25-6981 respectively, prevented LTP of auditory thalamic inputs to the lateral amygdala. Conversely, LTD induction in this pathway was prevented by blockade of GluN2B, but not GluN2A receptors. As this pathway plays a critical role in the acquisition, retrieval and extinction of a learned auditory-cue fear association, we next examined the effects of blockade of GluN2A and GluN2B receptors on the development and retention of a conditioned fear response. Administration of NVP-AAM077, but not Ro25-6981, prior to conditioning disrupted the expression of conditioned fear 24h later. Conversely, Ro25-6981 but not NVP-AAM077 impaired extinction of the conditioned fear response. These data expand on previous work showing that LTP/D in the thalamic-lateral amygdala pathway is dependent on NMDA receptors, by demonstrating selective roles for GluN2A and GluN2B NMDA receptor subunits in LTP and LTD respectively. Furthermore, GluN2A receptor activation and associated LTP may be involved specifically in the initial formation and/or stabilization of a learned fear response, whereas GluN2B receptor activation and associated LTD may facilitate the suppression of Pavlovian fear responses during extinction. This article is part of a Special Issue entitled 'Post-Traumatic Stress Disorder'.

  16. Homology modelling of the human adenosine A2B receptor based on X-ray structures of bovine rhodopsin, the beta2-adrenergic receptor and the human adenosine A2A receptor.

    PubMed

    Sherbiny, Farag F; Schiedel, Anke C; Maass, Astrid; Müller, Christa E

    2009-11-01

    A three-dimensional model of the human adenosine A2B receptor was generated by means of homology modelling, using the crystal structures of bovine rhodopsin, the beta2-adrenergic receptor, and the human adenosine A2A receptor as templates. In order to compare the three resulting models, the binding modes of the adenosine A2B receptor antagonists theophylline, ZM241385, MRS1706, and PSB601 were investigated. The A2A-based model was much better able to stabilize the ligands in the binding site than the other models reflecting the high degree of similarity between A2A and A2B receptors: while the A2B receptor shares about 21% of the residues with rhodopsin, and 31% with the beta2-adrenergic receptor, it is 56% identical to the adenosine A2A receptor. The A2A-based model was used for further studies. The model included the transmembrane domains, the extracellular and the intracellular hydrophilic loops as well as the terminal domains. In order to validate the usefulness of this model, a docking analysis of several selective and nonselective agonists and antagonists was carried out including a study of binding affinities and selectivities of these ligands with respect to the adenosine A2A and A2B receptors. A common binding site is proposed for antagonists and agonists based on homology modelling combined with site-directed mutagenesis and a comparison between experimental and calculated affinity data. The new, validated A2B receptor model may serve as a basis for developing more potent and selective drugs.

  17. Role of 5-HT2A and 5-HT2C receptors in the stimulus effects of hallucinogenic drugs. II: Reassessment of LSD false positives.

    PubMed

    Fiorella, D; Rabin, R A; Winter, J C

    1995-10-01

    In the context of animal studies of hallucinogens, an LSD-false positive is defined as a drug known to be devoid of hallucinogenic activity in humans but which nonetheless fully mimics LSD in animals. Quipazine, MK-212, lisuride, and yohimbine have all been reported to be LSD false positives. The present study was designed to determine whether these compounds also substitute for the stimulus effects of the more pharmacologically selective hallucinogen (-)DOM (0.56 mg/kg, 75-min pretreatment time). The LSD and (-)DOM stimuli fully generalized to quipazine (3.0 mg/kg) and lisuride (0.2 mg/kg), but only partially generalized to MK-212 (0.1-1.0 mg/kg) and yohimbine (2-20 mg/kg). In combination tests, pirenpirone (0.08 mg/kg), a compound with both D2 and 5-HT2A affinity, blocked the substitution of quipazine and lisuride for the (-)DOM stimulus. Ketanserin (2.5 mg/kg), an antagonist with greater than 1 order of magnitude higher affinity for 5-HT2A receptors than either 5-HT2C or D2 receptors, also fully blocked the substitution of these compounds for the (-)DOM stimulus, while the selective D2 antagonist thiothixene (0.1-1.0 mg/kg) failed to block the substitution of lisuride for the (-)DOM stimulus. These results suggest that quipazine and lisuride substitute for the stimulus properties of the phenylalkglamine hallucinogen (-)DOM via agonist activity at 5-HT2A receptors. In addition, these results suggest that 5-HT2A agonist activity may be required, but is not in itself sufficient, for indolamine and phenylalkglamine compounds to elicit hallucinations in humans. Finally, it is concluded that MK-212 and yohimbine are neither LSD nor (-)DOM false positives.

  18. Effect of GABAergic ligands on the anxiolytic-like activity of DOI (a 5-HT(2A/2C) agonist) in the four-plate test in mice.

    PubMed

    Massé, Fabienne; Hascoët, Martine; Bourin, Michel

    2007-01-01

    5-HTergic and GABAergic systems are involved in neurobiology of anxiety. Precedent studies have demonstrated that SSRIs possessed an anxiolytic-like effect in the four-plate test (FPT) at doses that did not modify spontaneous locomotor activity. This effect seems to be mediated through the activation of 5-HT(2A) postsynaptic receptors. The purpose of the present study was to examine the implication of GABA system in the anxiolytic-like activity of DOI in the FPT. To achieve this, the co-administration of DOI (5-HT(2A/2C) receptor agonists) with GABA(A) and GABA(B) receptor ligands was evaluated in the FPT. Alprazolam, diazepam and muscimol (for higher dose) potentiated the anxiolytic-like effect of DOI. Bicuculline, picrotoxin and baclofen inhibited the anxiolytic-like effect of DOI. Flumazenil and CGP 35348 had no effect on the anxiolytic-like activity of DOI. These results suggest that the GABA system seems to be strongly implicated in the anxiolytic-like activity of DOI in the FPT.

  19. Target discrimination by RNA-binding proteins: role of the ancillary protein U2A' and a critical leucine residue in differentiating the RNA-binding specificity of spliceosomal proteins U1A and U2B".

    PubMed Central

    Rimmele, M E; Belasco, J G

    1998-01-01

    The spliceosomal proteins U1A and U2B" each use a homologous RRM domain to bind specifically to their respective snRNA targets, U1hpll and U2hpIV, two stem-loops that are similar yet distinct in sequence. Previous studies have shown that binding of U2B" to U2hpIV is facilitated by the ancillary protein U2A', whereas specific binding of U1A to U1hpll requires no cofactor. Here we report that U2A' enables U2B" to distinguish the loop sequence of U2hpIV from that of U1hpll but plays no role in stem sequence discrimination. Although U2A' can also promote heterospecific binding of U1A to U2hpIV, a much higher concentration of the ancillary protein is required due to the approximately 500-fold greater affinity of U2A' for U2B". Additional experiments have identified a single leucine residue in U1A(Leu-44) that is critical for the intrinsic specificity of this protein for the loop sequence of U1 hpll in preference to that of U2hpIV. Our data suggest that most of the difference in RNA-binding specificity between U1A and U2B" can be accounted for by this leucine residue and by the contribution of the ancillary protein U2A' to the specificity of U2B". PMID:9814759

  20. Effect of porcine circovirus type 2a or 2b on infection kinetics and pathogenicity of two genetically divergent strains of porcine reproductive and respiratory syndrome virus in the conventional pig model

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The objective of this study was to characterize the infection dynamics and pathogenicity of two heterologous type 2 porcine reproductive and respiratory syndrome virus (PRRSV) isolates in a conventional pig model under the influence of concurrent porcine circovirus (PCV) subtype 2a or 2b infection. ...

  1. Both NR2A and NR2B Subunits of the NMDA Receptor Are Critical for Long-Term Potentiation and Long-Term Depression in the Lateral Amygdala of Horizontal Slices of Adult Mice

    ERIC Educational Resources Information Center

    Muller, Tobias; Albrecht, Doris; Gebhardt, Christine

    2009-01-01

    The lateral nucleus of the amygdala (LA) is implicated in emotional and social behaviors. We recently showed that in horizontal brain slices, activation of NMDA receptors (NMDARs) is a requirement for persistent synaptic alterations in the LA, such as long-term potentiation (LTP) and long-term depression (LTD). In the LA, NR2A- and NR2B-type NMDRs…

  2. Amygdala Infusions of an NR2B-Selective or an NR2A-Preferring NMDA Receptor Antagonist Differentially Influence Fear Conditioning and Expression in the Fear-Potentiated Startle Test

    ERIC Educational Resources Information Center

    Walker, David L.; Davis, Michael

    2008-01-01

    Within the amygdala, most N-methyl-D-aspartic acid (NMDA) receptors consist of NR1 subunits in combination with either NR2A or NR2B subunits. Because the particular subunit composition greatly influences the receptors' properties, we investigated the contribution of both subtypes to fear conditioning and expression. To do so, we infused the…

  3. A double dissociation in the effects of 5-HT2A and 5-HT2C receptors on the acquisition and expression of conditioned defeat in Syrian hamsters

    PubMed Central

    Harvey, Marquinta L.; Swallows, Cody L.; Cooper, Matthew A.

    2012-01-01

    Previous research indicates that serotonin enhances the development of stress-induced changes in behavior, although it is unclear which serotonin receptors mediate this effect. 5-HT2 receptors are potential candidates because activation at these receptors is associated with increased fear and anxiety. In this study we investigated whether pharmacological treatments targeting 5-HT2 receptors would alter the acquisition and expression of conditioned defeat. Conditioned defeat is a social defeat model in Syrian hamsters in which individuals display increased submissive and defensive behavior and a loss of territorial aggression when tested with a novel intruder 24 hours after an acute social defeat. The nonselective 5-HT2 receptor agonist mCPP (0.0, 0.3, 1.0 or 3.0 mg/kg) was injected either prior to social defeat training or prior to conditioned defeat testing. Also, the 5-HT2A receptor antagonist MDL 11,939 (0.0, 0.5 or 2.0 mg/kg) was injected either prior to social defeat training or prior to conditioned defeat testing. Injection of mCPP prior to testing increased the expression of conditioned defeat, but injection of mCPP prior to training did not alter the acquisition of conditioned defeat. Conversely, injection of MDL 11,939 prior to training reduced the acquisition of conditioned defeat, but injection of MDL 11,939 prior to testing did not alter the expression of conditioned defeat. Our data suggest that mCPP activates 5-HT2C receptors during testing to enhance the display of submissive and defensive behavior, whereas MDL 11,939 blocks 5-HT2A receptors during social defeat to disrupt the development of the conditioned defeat response. In sum, these results suggest that serotonin acts at separate 5-HT2 receptors to facilitate the acquisition and expression of defeat-induced changes in social behavior. PMID:22708954

  4. Mutant USA strain of porcine circovirus type 2 (mPCV2) exhibits similar virulence to the classical PCV2a and PCV2b strains in caesarean-derived, colostrum-deprived pigs.

    PubMed

    Opriessnig, Tanja; Xiao, Chao-Ting; Gerber, Priscilla F; Halbur, Patrick G; Matzinger, Shannon R; Meng, Xiang-Jin

    2014-11-01

    In 2012, a mutant porcine circovirus type 2 (mPCV2) strain was identified in cases of PCV-associated disease (PCVAD) in the USA. The mPCV2 had an additional amino acid, lysine (K), in the capsid at position 234. The objectives of this study were to compare the pathogenicity of mPCV2, PCV2a and PCV2b in pigs using biologically pure infectious virus stocks derived from respective infectious DNA clones, and to investigate the importance of genotype-specific ORF2 and the presence of lysine at position 234 of the capsid. A total of 47, 2-week-old, caesarean-derived, colostrum-deprived (CDCD) pigs were assigned to one of seven groups. At 3 weeks of age, the pigs were experimentally inoculated with saline, PCV2a, PCV2b, mPCV2, PCV2b-234-K (lysine addition in ORF2), chimeric PCV2b-ORF1/mPCV2-ORF2 or reciprocal chimeric mPCV2-ORF1/PCV2b-ORF2. All pigs were necropsied 21 days post-infection (p.i.). Gross lesions were limited to visible icterus and loss of body condition in a portion of the mPCV2 pigs. The amount of PCV2 DNA was significantly higher in pigs inoculated with mPCV2 compared with PCV2b in sera at 7 days p.i. and faecal swabs at 14 days p.i. Based on lymphoid lesions, a higher prevalence of PCVAD was seen in pigs infected with PCV2s containing the additional 234-K (64.3 %) compared with those infected with a PCV2 with the regular 233 bp ORF2 (40 %). Results indicated that all PCV2 isolates were capable of inducing severe lesions and disease in the CDCD pig model, and there was no significant difference in virulence.

  5. Efficacy, Safety, and Dose of Pafuramidine, a New Oral Drug for Treatment of First Stage Sleeping Sickness, in a Phase 2a Clinical Study and Phase 2b Randomized Clinical Studies

    PubMed Central

    Burri, Christian; Yeramian, Patrick D.; Merolle, Ada; Serge, Kazadi Kyanza; Mpanya, Alain; Lutumba, Pascal; Mesu, Victor Kande Betu Ku; Lubaki, Jean-Pierre Fina; Mpoto, Alfred Mpoo; Thompson, Mark; Munungu, Blaise Fungula; Josenando, Théophilo; Bernhard, Sonja C.; Olson, Carol A.; Blum, Johannes; Tidwell, Richard R.; Pohlig, Gabriele

    2016-01-01

    Background Sleeping sickness (human African trypanosomiasis [HAT]) is caused by protozoan parasites and characterized by a chronic progressive course, which may last up to several years before death. We conducted two Phase 2 studies to determine the efficacy and safety of oral pafuramidine in African patients with first stage HAT. Methods The Phase 2a study was an open-label, non-controlled, proof-of-concept study where 32 patients were treated with 100 mg of pafuramidine orally twice a day (BID) for 5 days at two trypanosomiasis reference centers (Angola and the Democratic Republic of the Congo [DRC]) between August 2001 and November 2004. The Phase 2b study compared pafuramidine in 41 patients versus standard pentamidine therapy in 40 patients. The Phase 2b study was open-label, parallel-group, controlled, randomized, and conducted at two sites in the DRC between April 2003 and February 2007. The Phase 2b study was then amended to add an open-label sequence (Phase 2b-2), where 30 patients received pafuramidine for 10 days. The primary efficacy endpoint was parasitologic cure at 24 hours (Phase 2a) or 3 months (Phase 2b) after treatment completion. The primary safety outcome was the rate of occurrence of World Health Organization Toxicity Scale Grade 3 or higher adverse events. All subjects provided written informed consent. Findings/Conclusion Pafuramidine for the treatment of first stage HAT was comparable in efficacy to pentamidine after 10 days of dosing. The cure rates 3 months post-treatment were 79% in the 5-day pafuramidine, 100% in the 7-day pentamidine, and 93% in the 10-day pafuramidine groups. In Phase 2b, the percentage of patients with at least 1 treatment-emergent adverse event was notably higher after pentamidine treatment (93%) than pafuramidine treatment for 5 days (25%) and 10 days (57%). These results support continuation of the development program for pafuramidine into Phase 3. PMID:26881924

  6. Synthesis and structure-affinity relationships of novel small molecule natural product derivatives capable of discriminating between serotonin 5-HT1A, 5-HT2A, 5-HT2C receptor subtypes

    PubMed Central

    Cummings, David F.; Canseco, Diana C.; Sheth, Pratikkumar; Johnson, James E.; Schetz, John A.

    2010-01-01

    Efforts to develop ligands that distinguish between clinically relevant 5-HT2A and 5-HT2C serotonin receptor subtypes have been challenging, because their sequences have high homology. Previous studies reported that a novel aplysinopsin belonging to a chemical class of natural products isolated from a marine sponge was selective for the 5-HT2C over the 5-HT2A receptor subtype. Our goal was to explore the 5-HT2A/2C receptor structure-affinity relationships of derivatives based on the aplysinopsin natural product pharmacophore. Twenty aplysinopsin derivatives were synthesized, purified and tested for their affinities for cloned human serotonin 5-HT1A, 5-HT2A and 5-HT2C receptor subtypes. Four compounds in this series had >30-fold selectivity for 5-HT2A or 5-HT2C receptors. The compound (E)-5-((5,6-dichloro-1H-indol-3-yl)methylene)-2-imino-1,3-dimethylimidazolidin-4-one (UNT-TWU-22, 16) had approximately 2100-fold selectivity for the serotonin 5-HT2C receptor subtype: an affinity for 5-HT2C equal to 46 nM and no detectable affinity for the 5-HT1A or 5-HT2A receptor subtypes. The two most important factors controlling 5-HT2A or 5-HT2C receptor subtype selectivity were the combined R1, R3-alkylation of the imidazolidinone ring and the type and number of halogens on the indole ring of the aplysinopsin pharmacophore. PMID:20570529

  7. Determination of O2(a1 delta g) and O2(b1 sigma+ g) yields in the reaction O + ClO --> Cl + O2: implications for photochemistry in the atmosphere of Venus

    NASA Technical Reports Server (NTRS)

    Leu, M. T.; Yung, Y. L.

    1987-01-01

    A discharge flow apparatus with chemiluminescence detector has been used to study the reaction O + ClO --> Cl + O2, where O2 = O2(a1 delta g) or O2(b1 sigma+ g). The measured quantum yields for producing O2(a1 delta g) and O2(b1 sigma+ g) in the above reaction are less than 2.5 x 10(-2) and equal to (4.4 +/- 1.1) x 10(-4), respectively. The observed O2(a1 delta g) airglow of Venus cannot be explained in the context of standard photochemistry using our experimental results and those reported in recent literature. The possibility of an alternative source of O atoms derived from SO2 photolysis in the mesosphere of Venus is suggested.

  8. Albumin Stimulates the Activity of the Human UDP-Glucuronosyltransferases 1A7, 1A8, 1A10, 2A1 and 2B15, but the Effects Are Enzyme and Substrate Dependent

    PubMed Central

    Svaluto-Moreolo, Paolo; Dziedzic, Klaudyna; Yli-Kauhaluoma, Jari; Finel, Moshe

    2013-01-01

    Human UDP-glucuronosyltransferases (UGTs) are important enzymes in metabolic elimination of endo- and xenobiotics. It was recently shown that addition of fatty acid free bovine serum albumin (BSA) significantly enhances in vitro activities of UGTs, a limiting factor in in vitro–in vivo extrapolation. Nevertheless, since only few human UGT enzymes were tested for this phenomenon, we have now performed detailed enzyme kinetic analysis on the BSA effects in six previously untested UGTs, using 2–4 suitable substrates for each enzyme. We also examined some of the previously tested UGTs, but using additional substrates and a lower BSA concentration, only 0.1%. The latter concentration allows the use of important but more lipophilic substrates, such as estradiol and 17-epiestradiol. In five newly tested UGTs, 1A7, 1A8, 1A10, 2A1, and 2B15, the addition of BSA enhanced, to a different degree, the in vitro activity by either decreasing reaction’s Km, increasing its Vmax, or both. In contrast, the activities of UGT2B17, another previously untested enzyme, were almost unaffected. The results of the assays with the previously tested UGTs, 1A1, 1A6, 2B4, and 2B7, were similar to the published BSA only as far as the BSA effects on the reactions’ Km are concerned. In the cases of Vmax values, however, our results differ significantly from the previously published ones, at least with some of the substrates. Hence, the magnitude of the BSA effects appears to be substrate dependent, especially with respect to Vmax increases. Additionally, the BSA effects may be UGT subfamily dependent since Km decreases were observed in members of subfamilies 1A, 2A and 2B, whereas large Vmax increases were only found in several UGT1A members. The results shed new light on the complexity of the BSA effects on the activity and enzyme kinetics of the human UGTs. PMID:23372764

  9. The role of GluN2A and GluN2B NMDA receptor subunits in AgRP and POMC neurons on body weight and glucose homeostasis

    PubMed Central

    Üner, Aykut; Gonçalves, Gabriel H.M.; Li, Wenjing; Porceban, Matheus; Caron, Nicole; Schönke, Milena; Delpire, Eric; Sakimura, Kenji; Bjørbæk, Christian

    2015-01-01

    Objective Hypothalamic agouti-related peptide (AgRP) and pro-opiomelanocortin (POMC) expressing neurons play critical roles in control of energy balance. Glutamatergic input via n-methyl-d-aspartate receptors (NMDARs) is pivotal for regulation of neuronal activity and is required in AgRP neurons for normal body weight homeostasis. NMDARs typically consist of the obligatory GluN1 subunit and different GluN2 subunits, the latter exerting crucial differential effects on channel activity and neuronal function. Currently, the role of specific GluN2 subunits in AgRP and POMC neurons on whole body energy and glucose balance is unknown. Methods We used the cre-lox system to genetically delete GluN2A or GluN2B only from AgRP or POMC neurons in mice. Mice were then subjected to metabolic analyses and assessment of AgRP and POMC neuronal function through morphological studies. Results We show that loss of GluN2B from AgRP neurons reduces body weight, fat mass, and food intake, whereas GluN2B in POMC neurons is not required for normal energy balance control. GluN2A subunits in either AgRP or POMC neurons are not required for regulation of body weight. Deletion of GluN2B reduces the number of AgRP neurons and decreases their dendritic length. In addition, loss of GluN2B in AgRP neurons of the morbidly obese and severely diabetic leptin-deficient Lepob/ob mice does not affect body weight and food intake but, remarkably, leads to full correction of hyperglycemia. Lepob/ob mice lacking GluN2B in AgRP neurons are also more sensitive to leptin's anti-obesity actions. Conclusions GluN2B-containing NMDA receptors in AgRP neurons play a critical role in central control of body weight homeostasis and blood glucose balance via mechanisms that likely involve regulation of AgRP neuronal survival and structure, and modulation of hypothalamic leptin action. PMID:26500840

  10. Cutting edge: The adapters EAT-2A and -2B are positive regulators of CD244- and CD84-dependent NK cell functions in the C57BL/6 mouse.

    PubMed

    Wang, Ninghai; Calpe, Silvia; Westcott, Jill; Castro, Wilson; Ma, Chunyan; Engel, Pablo; Schatzle, John D; Terhorst, Cox

    2010-11-15

    EWS/FLI1-activated transcript 2 (EAT-2)A and EAT-2B are single SH2-domain proteins, which bind to phosphorylated tyrosines of signaling lymphocyte activation molecule family receptors in murine NK cells. While EAT-2 is a positive regulator in human cells, a negative regulatory role was attributed to the adapter in NK cells derived from EAT-2A-deficient 129Sv mice. To evaluate whether the genetic background or the presence of a selection marker in the mutant mice could influence the regulatory mode of these adapters, we generated EAT-2A-, EAT-2B-, and EAT-2A/B-deficient mice using C57BL/6 embryonic stem cells. We found that NK cells from EAT-2A- and EAT-2A/B-deficient mice were unable to kill tumor cells in a CD244- or CD84-dependent manner. Furthermore, EAT-2A/B positively regulate phosphorylation of Vav-1, which is known to be implicated in NK cell killing. Thus, as in humans, the EAT-2 adapters act as positive regulators of signaling lymphocyte activation molecule family receptor-specific NK cell functions in C57BL/6 mice.

  11. Depletion of H2A-H2B dimers in Saccharomyces cerevisiae triggers meiotic arrest by reducing IME1 expression and activating the BUB2-dependent branch of the spindle checkpoint.

    PubMed Central

    Hanlon, Sean E; Norris, David N; Vershon, Andrew K

    2003-01-01

    In the yeast Saccharomyces cerevisiae, diploid strains carrying homozygous hta1-htb1Delta mutations express histone H2A-H2B dimers at a lower level than do wild-type cells. Although this mutation has only minor effects on mitotic growth, it causes an arrest in sporulation prior to the first meiotic division. In this report, we show that the hta1-htb1Delta mutant exhibits reduced expression of early and middle-sporulation-specific genes and that the meiotic arrest of the hta1-htb1Delta mutant can be partially bypassed by overexpression of IME1. Additionally, deletions of BUB2 or BFA1, components of one branch of the spindle checkpoint pathway, bypass the meiotic arrest. Mutations in the other branch of the pathway or in the pachytene checkpoint are unable to suppress the meiotic block. These observations indicate that depletion of the H2A-H2B dimer blocks sporulation by at least two mechanisms: disruption of the expression of meiotic regulatory genes and activation of the spindle checkpoint. Our results show that the failure to progress through the meiotic pathway is not the result of global chromosomal alterations but that specific aspects of meiosis are sensitive to depletion of the H2A-H2B dimer. PMID:12930743

  12. Role of the NR2A/2B subunits of the N-methyl-D-aspartate receptor in glutamate-induced glutamic acid decarboxylase alteration in cortical GABAergic neurons in vitro.

    PubMed

    Monnerie, H; Hsu, F-C; Coulter, D A; Le Roux, P D

    2010-12-29

    The vulnerability of brain neuronal cell subpopulations to neurologic insults varies greatly. Among cells that survive a pathological insult, for example ischemia or brain trauma, some may undergo morphological and/or biochemical changes that may compromise brain function. The present study is a follow-up of our previous studies that investigated the effect of glutamate-induced excitotoxicity on the GABA synthesizing enzyme glutamic acid decarboxylase (GAD65/67)'s expression in surviving DIV 11 cortical GABAergic neurons in vitro [Monnerie and Le Roux, (2007) Exp Neurol 205:367-382, (2008) Exp Neurol 213:145-153]. An N-methyl-D-aspartate receptor (NMDAR)-mediated decrease in GAD expression was found following glutamate exposure. Here we examined which NMDAR subtype(s) mediated the glutamate-induced change in GAD protein levels. Western blotting techniques on cortical neuron cultures showed that glutamate's effect on GAD proteins was not altered by NR2B-containing diheteromeric (NR1/NR2B) receptor blockade. By contrast, blockade of triheteromeric (NR1/NR2A/NR2B) receptors fully protected against a decrease in GAD protein levels following glutamate exposure. When receptor location on the postsynaptic membrane was examined, extrasynaptic NMDAR stimulation was observed to be sufficient to decrease GAD protein levels similar to that observed after glutamate bath application. Blocking diheteromeric receptors prevented glutamate's effect on GAD proteins after extrasynaptic NMDAR stimulation. Finally, NR2B subunit examination with site-specific antibodies demonstrated a glutamate-induced, calpain-mediated alteration in NR2B expression. These results suggest that glutamate-induced excitotoxic NMDAR stimulation in cultured GABAergic cortical neurons depends upon subunit composition and receptor location (synaptic vs. extrasynaptic) on the neuronal membrane. Biochemical alterations in surviving cortical GABAergic neurons in various disease states may contribute to the altered

  13. Determination of O2(a1Delta g) and O2(b1Sigma + g) yields in the reaction O + ClO yields Cl + O2 - Implications for photochemistry in the atmosphere of Venus

    NASA Technical Reports Server (NTRS)

    Leu, Ming-Taun; Yung, Yuk L.

    1987-01-01

    A discharge flow apparatus with a chemiluminescence detector was used to investigate the reaction O + ClO yields Cl + O2(asterisk), where O2(asterisk) = O2(a1Delta g) or O2(b1Sigma + g). It is found that the observed O2(a1Delta g) airglow of Venus cannot be explained in the framework of standard photochemistry using the experimental results obtained here and those reported in the recent literature. The possibility of an alternative source of O atoms derived from SO2 photolysis in the Venus mesosphere is suggested.

  14. Adenosine A(1), A(2a), A(2b), and A(3) receptors in hematopoiesis. 2. Expression of receptor mRNA in resting and lipopolysaccharide-activated mouse RAW 264.7 macrophages.

    PubMed

    Streitová, D; Hofer, M; Holá, J; Vacek, A; Pospísil, M

    2010-01-01

    Expression of mRNA for adenosine receptor subtypes A(1), A(2a), A(2b), and A(3) in normal and lipopolysaccharide (LPS)-activated murine RAW 264.7 macrophages has been investigated using the method of quantitative real-time polymerase chain reaction. The results have shown a very low, unquantifiable expression of adenosine A(1) receptor mRNA in both normal and LPS-activated macrophages. The other three adenosine receptor mRNAs have been found to be expressed at various but always quantifiable levels. Activation of the macrophages by LPS induced upregulation of the expression of adenosine receptor A(2a) and A(2b) mRNA, whereas the expression of adenosine receptor A(3) mRNA was downregulated. Unstimulated macrophages exhibited a high expression of the A(2b) adenosine receptor mRNA. The findings are discussed from the point of view of the antiinflammatory and hematopoiesis-stimulating roles of the adenosine receptor signaling.

  15. Cost-effectiveness analysis of treatment with peginterferon-alfa-2a versus peginterferon-alfa-2b for patients with chronic hepatitis C under the public payer perspective in Brazil

    PubMed Central

    2013-01-01

    Background Chronic hepatitis C affects approximately 170 million people worldwide, and thus being one of the main causes of chronic liver disease. About 20% of patients with chronic hepatitis C will develop cirrhosis over 20 years, and present an increased risk of developing hepatic complications. Sustained virological response (SVR) is associated with a better prognosis compared to untreated patients and treatment failures. The objective of this analysis was to compare treatment costs and outcomes of pegylated interferon-alfa-2a versus pegylated interferon-alfa-2b, both associated with ribavirin, in the therapeutic scheme of 24 weeks and 48 week for hepatitis C genotypes 2/3 and genotype 1, respectively, under the Brazilian Public Health System (SUS) scenario. Methods To project disease progression, a Markov model was built based on clinical stages of chronic disease. A Delphi panel was conducted to evaluate medical resources related to each stage, followed by costing of related materials, services, procedures and pharmaceutical products. The evaluation was made from a public payer perspective. The source used for costing was government reimbursement procedures list (SAI/SIH–SUS). Drug acquisition costs were obtained from the Brazilian Official Gazette and “Banco de Preços em Saúde” (government official source). It was assumed a mean patient weight of 70 kg. Costs were reported in 2011 Brazilian Reais (US$1 ≈ $Brz1.80). A systematic review followed by a meta-analysis of the 7 identified randomized controlled trials (RCTs) which compared pegylated interferons, was conducted for obtaining relative efficacy of both drugs: for genotype 2/3, mean rate of SVR was 79.2% for peginterferon-alfa-2a and 73.8% for peginterferon-alfa-2b. For genotype 1, SVR mean rate was 42.09% versus 33.44% (peginterferon-alfa-2a and peginterferon-alfa-2b respectively). Time horizon considered was lifetime. Discount rate for costs and outcomes was 5%, according to Brazilian

  16. Essential role of GluD1 in dendritic spine development and GluN2B to GluN2A NMDAR subunit switch in the cortex and hippocampus reveals ability of GluN2B inhibition in correcting hyperconnectivity

    PubMed Central

    Gupta, Subhash C.; Yadav, Roopali; Pavuluri, Ratnamala; Morley, Barbara J.; Stairs, Dustin J.; Dravid, Shashank M.

    2015-01-01

    The glutamate delta-1 (GluD1) receptor is highly expressed in the forebrain. We have previously shown that loss of GluD1 leads to social and cognitive deficits in mice, however, its role in synaptic development and neurotransmission remains poorly understood. Here we report that GluD1 is enriched in the medial prefrontal cortex (mPFC) and GluD1 knockout mice exhibit a higher dendritic spine number, greater excitatory neurotransmission as well as higher number of synapses in mPFC. In addition abnormalities in the LIMK1-cofilin signaling, which regulates spine dynamics, and a lower ratio of GluN2A/GluN2B expression was observed in the mPFC in GluD1 knockout mice. Analysis of the GluD1 knockout CA1 hippocampus similarly indicated the presence of higher spine number and synapses and altered LIMK1-cofilin signaling. We found that systemic administration of an N-methyl-d-aspartate (NMDA) receptor partial agonist d-cycloserine (DCS) at a high-dose, but not at a low-dose, and a GluN2B-selective inhibitor Ro-25-6981 partially normalized the abnormalities in LIMK1-cofilin signaling and reduced excess spine number in mPFC. The molecular effects of high-dose DCS and GluN2B inhibitor correlated with their ability to reduce the higher stereotyped behavior and depression-like behavior in GluD1 knockout mice. Together these findings demonstrate a critical requirement for GluD1 in normal spine development in the cortex and hippocampus. Moreover, these results identify inhibition of GluN2Bcontaining receptors as a mechanism for reducing excess dendritic spines and stereotyped behavior which may have therapeutic value in certain neurodevelopmental disorders. PMID:25721396

  17. Spermidine and Ca(2+), but not Na(+), can permeate NMDA receptors consisting of GluN1 and GluN2A or GluN2B in the presence of Mg(2+).

    PubMed

    Hirose, Tadao; Saiki, Ryotaro; Yoshizawa, Yuki; Imamura, Masataka; Higashi, Kyohei; Ishii, Itsuko; Toida, Toshihiko; Williams, Keith; Kashiwagi, Keiko; Igarashi, Kazuei

    2015-08-01

    N-Methyl-D-aspartate receptors (NMDA receptors) are known to be permeable to Na(+) and Ca(2+) ions. In this study, we tested whether polyamines (putrescine, spermidine, spermine), organic cations found in cells, can permeate NMDA receptors expressed in Xenopus laevis oocytes and HEK293 cells. It was found that polyamines, especially spermidine, can permeate NMDA channels expressed from GluN1/GluN2A or GluN1/GluN2B activated by glycine and glutamate. Furthermore, spermidine and Ca(2+) influx through NMDA receptors was observed in the presence of Mg(2+), although Na(+) influx was strongly inhibited by Mg(2+). The Km values for spermidine influx through GluN1/GluN2A and GluN1/GluN2B were 2.2 mM and 2.7 mM, respectively in the presence of isotonic extracellular ion solutions. Spermidine uptake by NMDA receptors was dependent on the presence of glycine and glutamate, and inhibited by Ca(2+) and by memantine, an NMDA receptor channel blocker. The Km values for Ca(2+) influx through GluN1/GluN2A and GluN1/GluN2B were 4.6 mM and 3.3 mM, respectively, under the same ionic conditions. The results indicate that spermidine and Ca(2+), but not Na(+), can permeate NMDA receptors in the presence of Mg(2+). Spermidine, if released locally from presynaptic terminals (where its concentration is high in synaptosomes and synaptic vesicles) could permeate NMDA receptors and play a role in synaptic plasticity mediated by NMDA receptors together with Ca(2+).

  18. Behavioural Assessment of the A2a/NR2B Combination in the Unilateral 6-OHDA-Lesioned Rat Model: A New Method to Examine the Therapeutic Potential of Non-Dopaminergic Drugs

    PubMed Central

    Michel, Anne; Downey, Patrick; Van Damme, Xavier; De Wolf, Catherine; Schwarting, Rainer; Scheller, Dieter

    2015-01-01

    In Parkinson’s disease (PD), dopaminergic therapies are often associated with the development of motor complications. Attention has therefore been focused on the use of non-dopaminergic drugs. This study developed a new behavioural method capable of demonstrating the added value of combining adenosinergic and glutamatergic receptor antagonists in unilateral 6-OHDA lesioned rats. Rats were dosed orally with Tozadenant, a selective A2A receptor antagonist, and three different doses of Radiprodil, an NR2B-selective NMDA receptor antagonist. The drugs were given alone or in combination and rats were placed in an open-field for behavioural monitoring. Video recordings were automatically analysed. Five different behaviours were scored: distance traveled, ipsi- and contraversive turns, body position, and space occupancy. The results show that A2A or NR2B receptor antagonists given alone or in combination did not produce enhanced turning as observed with an active dose of L-Dopa/benserazide. Instead the treated rats maintained a straight body position, were able to shift from one direction to the other and occupied a significantly larger space in the arena. The highest “Tozadenant/Radiprodil” dose combination significantly increased all five behavioural parameters recorded compared to rats treated with vehicle or the same doses of the drugs alone. Our data suggest that the A2A/NR2B antagonist combination may be able to stimulate motor activity to a similar level as that achieved by L-Dopa but in the absence of the side-effects that are associated with dopaminergic hyperstimulation. If these results translate into the clinic, this combination could represent an alternative symptomatic treatment option for PD. PMID:26322641

  19. Nucleosomal histone proteins of L. donovani: a combination of recombinant H2A, H2B, H3 and H4 proteins were highly immunogenic and offered optimum prophylactic efficacy against Leishmania challenge in hamsters.

    PubMed

    Baharia, Rajendra K; Tandon, Rati; Sahasrabuddhe, Amogh A; Sundar, Shyam; Dube, Anuradha

    2014-01-01

    The present study includes cloning and expression of recombinant Leishmania donovani histone proteins (rLdH2B, rLdH3, rLdH2A and rLdH4), assessment of their immunogenicity in Leishmania infected cured patients/endemic contacts as well as in cured hamsters and finally evaluation of their prophylactic efficacy in hamsters against L. donovani challenge. All recombinant proteins were expressed and purified from the heterologous bacterial host system. Leishmania infected cured patients/endemic contacts as well as cured hamsters exhibited significantly higher proliferative responses to individual recombinant histones and their pooled combination (rLdH2B+rLdH3+rLdH2A+rLdH4) than those of L.donovani infected hosts. The L.donovani soluble antigens (SLD) stimulated PBMCs of cured/exposed and Leishmania patients to produce a mixed Thl/Th2-type cytokine profile, whereas rLdH2B, rLdH3, rLdH2A, rLdH4 and pooled combination (rLdH2-4) stimulated the production of Th1 cytokines IFN-γ, IL-12 and TNF-α but not Th2 cytokines IL-4 or IL-10. The immunogenicity of these histone proteins along with their combination was also checked in cured hamsters where they stimulated higher lymphoproliferation and Nitric oxide production in lymphocytes of cured hamsters than that of infected controls. Moreover, significantly increased IgG2 response, an indicative of cell mediated immunity, was observed in cured hamsters against these individual proteins and their combination as compared to infected hamsters. Further, it was demonstrated that rLdH2B, rLdH3, rLdH2A and rLdH4 and pooled combination were able to provide considerable protection for hamsters against L. donovani challenge. The efficacy was supported by the increased inducible Nitric Oxide Synthase (iNOS) mRNA transcripts and Th1-type cytokines--IFN-γ, IL-12 and TNF-α and down-regulation of IL-4, IL-10 and TGF-β. Hence, it is inferred that pooled rLdH2-4 elicits Thl-type of immune responses exclusively and confer considerable protection

  20. First identification of Porcine Circovirus Type 2b mutant in pigs from Uruguay.

    PubMed

    Ramos, Natalia; Mirazo, Santiago; Castro, Gustavo; Arbiza, Juan

    2015-07-01

    Porcine Circovirus Type 2 (PCV2) is a worldwide distributed virus and is considered an important emerging pathogen related to several distinct disease syndromes in pigs. PCV2 strains are classified into three genotypes: PCV2a, with five subtypes (2A-2E), PCV2b with three subtypes (1A-1C) and PCV2c, only found in Denmark. Recently, several reports suggested the circulation of newly emerging PCV2b mutants (mPCV2b) isolated from pigs with PCVAD in cases of suspected vaccine failure. In this work, we report for the first time the identification of mPCV2b in pigs from Uruguay, providing an additional evidence of a global circulation. Complete genome characterization and phylogenetic analysis reveal that Uruguayan strains, as well as mPCV2b previously reported are closely related to other sequences already classified as PCV2b-1C. Furthermore, results showed that mPCV2b presented different genetic markers in the capsid protein compared with classical PCV2a/b strains. Further investigation about antigenic shift of the mPCV2b strains including the Uruguayan isolates is needed.

  1. EPR spectroscopy of MolB2C2-a reveals mechanism of transport for a bacterial type II molybdate importer.

    PubMed

    Rice, Austin J; Alvarez, Frances J D; Schultz, Kathryn M; Klug, Candice S; Davidson, Amy L; Pinkett, Heather W

    2013-07-19

    In bacteria, ATP-binding cassette (ABC) transporters are vital for the uptake of nutrients and cofactors. Based on differences in structure and activity, ABC importers are divided into two types. Type I transporters have been well studied and employ a tightly regulated alternating access mechanism. Less is known about Type II importers, but much of what we do know has been observed in studies of the vitamin B12 importer BtuC2D2. MolB2C2 (formally known as HI1470/71) is also a Type II importer, but its substrate, molybdate, is ∼10-fold smaller than vitamin B12. To understand mechanistic differences among Type II importers, we focused our studies on MolBC, for which alternative conformations may be required to transport its relatively small substrate. To investigate the mechanism of MolBC, we employed disulfide cross-linking and EPR spectroscopy. From these studies, we found that nucleotide binding is coupled to a conformational shift at the periplasmic gate. Unlike the larger conformational changes in BtuCD-F, this shift in MolBC-A is akin to unlocking a swinging door: allowing just enough space for molybdate to slip into the cell. The lower cytoplasmic gate, identified in BtuCD-F as "gate I," remains open throughout the MolBC-A mechanism, and cytoplasmic gate II closes in the presence of nucleotide. Combining our results, we propose a peristaltic mechanism for MolBC-A, which gives new insight in the transport of small substrates by a Type II importer.

  2. EPR Spectroscopy of MolB2C2-A Reveals Mechanism of Transport for a Bacterial Type II Molybdate Importer*♦

    PubMed Central

    Rice, Austin J.; Alvarez, Frances J. D.; Schultz, Kathryn M.; Klug, Candice S.; Davidson, Amy L.; Pinkett, Heather W.

    2013-01-01

    In bacteria, ATP-binding cassette (ABC) transporters are vital for the uptake of nutrients and cofactors. Based on differences in structure and activity, ABC importers are divided into two types. Type I transporters have been well studied and employ a tightly regulated alternating access mechanism. Less is known about Type II importers, but much of what we do know has been observed in studies of the vitamin B12 importer BtuC2D2. MolB2C2 (formally known as HI1470/71) is also a Type II importer, but its substrate, molybdate, is ∼10-fold smaller than vitamin B12. To understand mechanistic differences among Type II importers, we focused our studies on MolBC, for which alternative conformations may be required to transport its relatively small substrate. To investigate the mechanism of MolBC, we employed disulfide cross-linking and EPR spectroscopy. From these studies, we found that nucleotide binding is coupled to a conformational shift at the periplasmic gate. Unlike the larger conformational changes in BtuCD-F, this shift in MolBC-A is akin to unlocking a swinging door: allowing just enough space for molybdate to slip into the cell. The lower cytoplasmic gate, identified in BtuCD-F as “gate I,” remains open throughout the MolBC-A mechanism, and cytoplasmic gate II closes in the presence of nucleotide. Combining our results, we propose a peristaltic mechanism for MolBC-A, which gives new insight in the transport of small substrates by a Type II importer. PMID:23709218

  3. Characterisation of human 5-hydroxytryptamine2A and 5-hydroxytryptamine2C receptors expressed in the human neuroblastoma cell line SH-SY5Y: comparative stimulation by hallucinogenic drugs.

    PubMed

    Newton, R A; Phipps, S L; Flanigan, T P; Newberry, N R; Carey, J E; Kumar, C; McDonald, B; Chen, C; Elliott, J M

    1996-12-01

    Stable transfection of the human neuroblastoma cell line SH-SY5Y with the human 5-hydroxytryptamine2A (5-HT2A) or 5-HT2C receptor cDNA produced cell lines demonstrating ligand affinities that correlated closely with those for the corresponding endogenous receptors in human frontal cortex and choroid plexus, respectively. Stimulation of the recombinant receptors by 5-HT induced phosphoinositide hydrolysis with higher potency but lower efficacy at the 5-HT2C receptor (pEC50 = 7.80 +/- 0.06) compared with the 5-HT2A receptor (pEC50 = 7.30 +/- 0.08). Activation of the 5-HT2A receptor caused a transient fourfold increase in intracellular Ca2+ concentration. Whole-cell recordings of cells clamped at -50 mV demonstrated a small inward current (2 pA) in response to 10 microM 5-HT for both receptors. There were no differences in potency or efficacy of phosphoinositide hydrolysis among four hallucinogenic [d-lysergic acid diethylamide (LSD), 1-(4-iodo-2,5-dimethoxyphenyl)-2-aminopropane (DOI), 5-methoxy-N,N-dimethyltryptamine, and mescaline] and three nonhallucinogenic drugs (m-chlorophenylpiperazine, quipazine, and ergotamine). Comparison of equipotent doses producing 20% of the maximal response induced by 5-HT revealed selective activation of the 5-HT2A receptor by LSD and to a lesser degree by DOI, mescaline, and ergotamine. Quipazine and 5-methoxy-N,N-dimethyltryptamine were relatively nonselective, whereas m-chlorophenylpiperazine selectively activated the 5-HT2C receptor. It is unlikely therefore that hallucinosis is mediated primarily by activity at the 5-HT2C receptor, whereas activity at the 5-HT2A receptor may represent an important but not unique mechanism associated with hallucinogenic drug action.

  4. The Role of GluN2A and GluN2B Subunits on the Effects of NMDA Receptor Antagonists in Modeling Schizophrenia and Treating Refractory Depression

    PubMed Central

    Jiménez-Sánchez, Laura; Campa, Leticia; Auberson, Yves P; Adell, Albert

    2014-01-01

    Paradoxically, N-methyl-D-aspartate (NMDA) receptor antagonists are used to model certain aspects of schizophrenia as well as to treat refractory depression. However, the role of different subunits of the NMDA receptor in both conditions is poorly understood. Here we used biochemical and behavioral readouts to examine the in vivo prefrontal efflux of serotonin and glutamate as well as the stereotypical behavior and the antidepressant-like activity in the forced swim test elicited by antagonists selective for the GluN2A (NVP-AAM077) and GluN2B (Ro 25-6981) subunits. The effects of the non-subunit selective antagonist, MK-801; were also studied for comparison. The administration of MK-801 dose dependently increased the prefrontal efflux of serotonin and glutamate and markedly increased the stereotypy scores. NVP-AAM077 also increased the efflux of serotonin and glutamate, but without the induction of stereotypies. In contrast, Ro 25-6981 did not change any of the biochemical and behavioral parameters tested. Interestingly, the administration of NVP-AAM077 and Ro 25-6981 alone elicited antidepressant-like activity in the forced swim test, in contrast to the combination of both compounds that evoked marked stereotypies. Our interpretation of the results is that both GluN2A and GluN2B subunits are needed to induce stereotypies, which might be suggestive of potential psychotomimetic effects in humans, but the antagonism of only one of these subunits is sufficient to evoke an antidepressant response. We also propose that GluN2A receptor antagonists could have potential antidepressant activity in the absence of potential psychotomimetic effects. PMID:24871546

  5. Fit 2-B FATHERS.

    ERIC Educational Resources Information Center

    Maiorano, Joseph J.

    2001-01-01

    Fit 2-B FATHERS is a parenting-skills education program for incarcerated adult males. The goals of this program are for participants to have reduced recidivism rates and a reduced risk of their children acquiring criminal records. These goals are accomplished by helping participants become physically, practically, and socially fit for the demands…

  6. Predictors of Virological Response in 3,235 Chronic HCV Egyptian Patients Treated with Peginterferon Alpha-2a Compared with Peginterferon Alpha-2b Using Statistical Methods and Data Mining Techniques.

    PubMed

    El Raziky, Maissa; Fathalah, Waleed Fouad; Zakaria, Zeinab; Eldeen, Hadeel Gamal; Abul-Fotouh, Amr; Salama, Ahmed; Awad, Abubakr; Esmat, Gamal; Mabrouk, Mahasen

    2016-05-01

    Despite the appearance of new oral antiviral drugs, pegylated interferon (PEG-IFN)/RBV may remain the standard of care therapy for some time, and several viral and host factors are reported to be correlated with therapeutic effects. This study aimed to reveal the independent variables associated with failure of sustained virological response (SVR) to PEG-IFN alpha-2a versus PEG-IFN alpha-2b in treatment of naive chronic hepatitis C virus (HCV) Egyptian patients using both statistical methods and data mining techniques. This retrospective cohort study included 3,235 chronic hepatitis C patients enrolled in a large Egyptian medical center: 1,728 patients had been treated with PEG-IFN alpha-2a plus ribavirin (RBV) and 1,507 patients with PEG-IFN alpha-2b plus RBV between 2007 and 2011. Both multivariate analysis and Reduced Error Pruning Tree (REPTree)-based model were used to reveal the independent variables associated with treatment response. In both treatment types, alpha-fetoprotein (AFP) >10 ng/mL and HCV viremia >600 × 10(3) IU/mL were the independent baseline variables associated with failure of SVR, while male gender, decreased hemoglobin, and thyroid-stimulating hormone were the independent variables associated with good response (P < 0.05). Using REPTree-based model showed that low AFP was the factor of initial split (best predictor) of response for either PEG-IFN alpha-2a or PEG-IFN alpha-2b (cutoff value 8.53, 4.89 ng/mL, AUROC = 0.68 and 0.61, P = 0.05). Serum AFP >10 ng/mL and viral load >600 × 10(3) IU/mL are variables associated with failure of response in both treatment types. REPTree-based model could be used to assess predictors of response. PMID:26859168

  7. The effect of intrahippocampal injections of ritanserin (5HT2A/2C antagonist) and granisetron (5HT3 antagonist) on learning as assessed in the spatial version of the water maze.

    PubMed

    Naghdi, Nasser; Harooni, Hooman E

    2005-02-28

    5HT(2A/2C) and 5HT(3) receptors have an important role in cognitive behavior specially in spatial learning and memory but the literature concerning the role of these receptors in hippocampus in cognition remains controversial. In the present study a 5HT(2A/2C) antagonist ritanserin (0, 2, 4, 8 microg/0.5 microl) and a 5HT(3) antagonist granisetron (0.0, 0.05, 0.25, 0.5 microg/0.5 microl) were injected bilaterally into the CA1 region of rat hippocampus, 20 min before each training session in Morris Water Maze (MWM) task. Compare with control group, ritanserin (4 microg/0.5 microl) significantly reduced the escape latency and traveled distance of swimming to platform, but granisetron (0.25 microg/0.5 microl) significantly increased those parameters. Both drugs had no effect on escape latency and traveled distance of a non-spatial visual discrimination task. These results suggest a differential role of 5HT(2A/2C) and 5HT(3) receptors during spatial learning that ritanserin improves rat performance in spatial discrimination task whereas granisetron impairs it.

  8. Aryne [3 + 2] cycloaddition with N-sulfonylpyridinium imides and in situ generated N-sulfonylisoquinolinium imides: a potential route to pyrido[1,2-b]indazoles and indazolo[3,2-a]isoquinolines.

    PubMed

    Zhao, Jingjing; Li, Pan; Wu, Chunrui; Chen, Hongli; Ai, Wenying; Sun, Renhong; Ren, Hailong; Larock, Richard C; Shi, Feng

    2012-03-01

    The aryne [3 + 2] cycloaddition process with pyridinium imides breaks the aromaticity of the pyridine ring. By equipping the imide nitrogen with a sulfonyl group, the intermediate readily eliminates a sulfinate anion to restore the aromaticity, leading to the formation of pyrido[1,2-b]indazoles. The scope and limitation of this reaction are discussed. As an extension of this chemistry, N-tosylisoquinolinium imides, generated in situ from N'-(2-alkynylbenzylidene)-tosylhydrazides via an AgOTf-catalyzed 6-endo-dig electrophilic cyclization, readily undergo aryne [3 + 2] cycloaddition to afford indazolo[3,2-a]-isoquinolines in the same pot, offering a highly efficient route to these potential anticancer agents.

  9. The immunodominant T helper 2 (Th2) response elicited in BALB/c mice by the Leishmania LiP2a and LiP2b acidic ribosomal proteins cannot be reverted by strong Th1 inducers

    PubMed Central

    Iborra, S; Abánades, D R; Parody, N; Carrión, J; Risueño, R M; Pineda, M A; Bonay, P; Alonso, C; Soto, M

    2007-01-01

    The search for disease-associated T helper 2 (Th2) Leishmania antigens and the induction of a Th1 immune response to them using defined vaccination protocols is a potential strategy to induce protection against Leishmania infection. Leishmania infantum LiP2a and LiP2b acidic ribosomal protein (P proteins) have been described as prominent antigens during human and canine visceral leishmaniasis. In this study we demonstrate that BALB/c mice infected with Leishmania major develop a Th2-like humoral response against Leishmania LiP2a and LiP2b proteins and that the same response is induced in BALB/c mice when the parasite P proteins are immunized as recombinant molecules without adjuvant. The genetic immunization of BALB/c mice with eukaryotic expression plasmids coding for these proteins was unable to redirect the Th2-like response induced by these antigens, and only the co-administration of the recombinant P proteins with CpG oligodeoxynucleotides (CpG ODN) promoted a mixed Th1/Th2 immune response. According to the preponderance of a Th2 or mixed Th1/Th2 responses elicited by the different regimens of immunization tested, no evidence of protection was observed in mice after challenge with L. major. Although alterations of the clinical outcome were not detected in mice presensitized with the P proteins, the enhanced IgG1 and interleukin (IL)-4 response against total Leishmania antigens in these mice may indicate an exacerbation of the disease. PMID:17900304

  10. The role of the 5-HT2A and 5-HT2C receptors in the stimulus effects of hallucinogenic drugs. III: The mechanistic basis for supersensitivity to the LSD stimulus following serotonin depletion.

    PubMed

    Fiorella, D; Helsley, S; Lorrain, D S; Rabin, R A; Winter, J C

    1995-10-01

    The present study was designed to determine the effects of p-chlorophenylalanine (PCPA) and p-chloroamphetamine (PCA) administration on (1) the levels of serotonin (5-hydroxytryptamine, 5-HT) and 5-hydroxyindoleacetic acid (5-HIAA) in rat brain, (2) the sensitivity of LSD-trained rats to the stimulus effects of LSD, and (3) the maximal levels of 5-HT2A and 5-HT2C receptor mediated phosphoinositide (PI) hydrolysis in rat brain. PCA and PCPA both produced a significant depletion of whole brain 5-HT and 5-HIAA concentrations. The depletion of serotonin with PCPA, but not PCA, resulted in supersensitivity of LSD-trained subjects to the stimulus effects of LSD. Neither PCPA nor PCA treatment altered the maximal level of 5-HT2A receptor-mediated PI hydrolysis. However, PCPA, but not PCA, treatment resulted in a significant upregulation (46%, P < 0.05) of the maximal level of 5-HT2C receptor mediated PI hydrolysis. These data suggest that upregulation of the 5-HT2C receptor mediates the supersensitivity to LSD discriminative stimulus which follows the depletion of central nervous system serotonin by PCPA.

  11. Boeing XF2B-1 (F2B-1)

    NASA Technical Reports Server (NTRS)

    1931-01-01

    Boeing XF2B-1 (F2B-1): Serving as the prototype for the F2B-1 shipboard fighter, the XF2B-1 differed visually in having a pointed spinner and an unbalanced rudder. Like many aircraft of its day, the Boeing model 69 was powered by a Pratt & Whitney Wasp radial engine.

  12. Association of Polymorphisms within the Serotonin Receptor Genes 5-HTR1A, 5-HTR1B, 5-HTR2A and 5-HTR2C and Migraine Susceptibility in a Turkish Population

    PubMed Central

    Yücel, Yavuz; Coşkun, Salih; Cengiz, Beyhan; Özdemir, Hasan H.; Uzar, Ertuğrul; Çim, Abdullah; Camkurt, M. Akif; Aluclu, M. Ufuk

    2016-01-01

    Objective Migraine, a highly prevelant headache disorder, is regarded as a polygenic multifactorial disease. Serotonin (5-HT) and their respective receptors have been implicated in the patogenesis. Methods We investigated the 5-HT1A, 5-HT1B, 5-HT2A, and 5-HT2C receptor gene polymorphisms and their association with migraine in Turkish patients. The rs6295, rs1300060, rs1228814, rs6311, rs6313, rs6314, rs6318, rs3813929 (−759C/T) and rs518147 polymorphisms were analyzed in 135 patients with migraine and 139 healthy subjects, using a BioMark 96.96 dynamic array system. Results We found no difference in the frequency of the analyzed eight out of nine polymorpisms between migraine and control groups. However, a significant association was found between the rs3813929 polymorphism in the promoter region of 5-HTR2C gene and migraine. Also, the allele of rs3813929 was more common in the migraine group. Conclusion This result suggests that the 5-HTR2C rs3813929 polymorphism can be a genetic risk factor for migraine in a Turkish population. PMID:27489378

  13. Effects of sex and chronic neonatal nicotine treatment on NKCC1, KCC2, BDNF, NR2A and NR2B mRNA expression in the postnatal rat hippocampus

    PubMed Central

    Damborsky, Joanne C.; Winzer-Serhan, Ursula H.

    2012-01-01

    Chronic exposure to nicotine during the first postnatal week in rats, a developmental period that corresponds to the third trimester of human gestation, results in sexually dimorphic long-term functional defects in the adult hippocampus. One potential cause could be the sex-specific differences in the maturation of GABAA receptor-mediated responses from excitatory to inhibitory, which depends on the expression of the Na2+/K+/Cl−-co-transporter NKCC1 and the K+/Cl− co-transporter KCC2. In the rat hippocampus, this switch occurs during the first and second postnatal week in females and males, respectively, and is regulated by nicotinic receptor activation. Excitatory GABAergic signaling can increase BDNF expression, which might exacerbate sex differences by impacting synaptogenesis. We hypothesized that chronic neonatal nicotine (CNN) exposure differentially regulates the expression of these co-transporters and BDNF in males and females. We use quantitative isotopic in situ hybridization to examine the expression of mRNAs for NKCC1, KCC2, BDNF, and NMDA receptor subunits NR2A and NR2B in the postnatal day (P) 5 and 8 rat hippocampus in both sexes that were either control-treated or with 6 mg/kg/day nicotine in milk formula (CNN) via gastric intubation starting at P1. In line with prolonged GABAergic excitation, we found that at P5 males had significantly higher mRNA expression of NKCC1 and BDNF than females. CNN treatment resulted in a significant increase in KCC2 and BDNF mRNA expression in male but not female hippocampus (p<0.05). Males also had higher expression of NR2A and lower expression of NR2B at P5 compared to females (p<0.05). At P8, there were neither sex nor treatment effects on mRNA expression, indicating the end of a critical period for sensitivity to nicotine. These results suggest that differential maturation of GABAAR-mediated responses result in sex-specific sensitivity to nicotine during early postnatal development, potentially explaining the

  14. Mild Hypothermia Combined with Hydrogen Sulfide Treatment During Resuscitation Reduces Hippocampal Neuron Apoptosis Via NR2A, NR2B, and PI3K-Akt Signaling in a Rat Model of Cerebral Ischemia-Reperfusion Injury.

    PubMed

    Dai, Hai-Bin; Xu, Miao-Miao; Lv, Jia; Ji, Xiang-Jun; Zhu, Si-Hai; Ma, Ru-Meng; Miao, Xiao-Lei; Duan, Man-Lin

    2016-09-01

    We investigated whether mild hypothermia combined with sodium hydrosulfide treatment during resuscitation improves neuron survival following cerebral ischemia-reperfusion injury beyond that observed for the individual treatments. Male Sprague-Dawley rats were divided into seven groups (n = 20 for each group). All rats underwent Pulsinelli 4-vessel occlusion. Ischemia was induced for 15 min using ligatures around the common carotid arteries, except for the sham group. Immediately after initiating reperfusion, the mild hypothermia (MH), sodium hydrosulfide (NaHS), hydroxylamine (HA), MH + NaHS, MH + HA, and ischemia-reperfusion (I/R) control groups received an intraperitoneal injection of saline, sodium hydrosulfide, hydroxylamine, sodium hydrosulfide, hydroxylamine, and saline, respectively, and mild hypothermia (32 to 33 °C) was induced in the MH, MH + NaHS, and MH + HA groups for 6 h. The levels of NR2A, NR2B, p-Akt, and p-Gsk-3β in the hippocampus of the MH, NaHS, and MH + NaHS groups were higher than those in the I/R control group, with the highest levels observed in the MH + NaHS group (P < 0.05). Treatment with hydroxylamine reduced the levels of these proteins in the HA and MH + HA groups, compared with the I/R control and MH groups, respectively. The apoptotic index of the CA1 region of the hippocampus was 45.2, 66.5, 63.5, and 84.8 % in the MH + NaHS, MH, NaHS, and I/R control groups, respectively (P < 0.05), indicating that the combination treatment shifted the NR2A/NR2B balance in favor of synaptic neuron stimulation and phosphatidylinositol 3'-kinase (PI3K)/Akt signaling. The combination of mild hypothermia and sodium hydrosulfide treatment for resuscitation following ischemia-reperfusion injury was more beneficial for reducing hippocampal apoptosis and pathology than that of mild hypothermia or hydrogen sulfide treatment alone. PMID:26350917

  15. Mild Hypothermia Combined with Hydrogen Sulfide Treatment During Resuscitation Reduces Hippocampal Neuron Apoptosis Via NR2A, NR2B, and PI3K-Akt Signaling in a Rat Model of Cerebral Ischemia-Reperfusion Injury.

    PubMed

    Dai, Hai-Bin; Xu, Miao-Miao; Lv, Jia; Ji, Xiang-Jun; Zhu, Si-Hai; Ma, Ru-Meng; Miao, Xiao-Lei; Duan, Man-Lin

    2016-09-01

    We investigated whether mild hypothermia combined with sodium hydrosulfide treatment during resuscitation improves neuron survival following cerebral ischemia-reperfusion injury beyond that observed for the individual treatments. Male Sprague-Dawley rats were divided into seven groups (n = 20 for each group). All rats underwent Pulsinelli 4-vessel occlusion. Ischemia was induced for 15 min using ligatures around the common carotid arteries, except for the sham group. Immediately after initiating reperfusion, the mild hypothermia (MH), sodium hydrosulfide (NaHS), hydroxylamine (HA), MH + NaHS, MH + HA, and ischemia-reperfusion (I/R) control groups received an intraperitoneal injection of saline, sodium hydrosulfide, hydroxylamine, sodium hydrosulfide, hydroxylamine, and saline, respectively, and mild hypothermia (32 to 33 °C) was induced in the MH, MH + NaHS, and MH + HA groups for 6 h. The levels of NR2A, NR2B, p-Akt, and p-Gsk-3β in the hippocampus of the MH, NaHS, and MH + NaHS groups were higher than those in the I/R control group, with the highest levels observed in the MH + NaHS group (P < 0.05). Treatment with hydroxylamine reduced the levels of these proteins in the HA and MH + HA groups, compared with the I/R control and MH groups, respectively. The apoptotic index of the CA1 region of the hippocampus was 45.2, 66.5, 63.5, and 84.8 % in the MH + NaHS, MH, NaHS, and I/R control groups, respectively (P < 0.05), indicating that the combination treatment shifted the NR2A/NR2B balance in favor of synaptic neuron stimulation and phosphatidylinositol 3'-kinase (PI3K)/Akt signaling. The combination of mild hypothermia and sodium hydrosulfide treatment for resuscitation following ischemia-reperfusion injury was more beneficial for reducing hippocampal apoptosis and pathology than that of mild hypothermia or hydrogen sulfide treatment alone.

  16. New halogenated tris-(phenylalkyl)amines as h5-HT2B receptor ligands.

    PubMed

    Kapadia, Nirav; Ahmed, Shahrear; Harding, Wayne W

    2016-07-15

    A series of compounds in which various halogen substituents were incorporated into a phenyl ring of a tris-(phenylalkyl)amine scaffold, was synthesized and evaluated for affinity to h5-HT2 receptors. In general, all compounds were found to have good affinity for the 5-HT2B receptor and were selective over 5-HT2A and 5-HT2C receptors. Compound 9i was the most selective compound in this study and is the highest affinity 5-HT2B receptor ligand bearing a tris-(phenylalkyl)amine scaffold to date. PMID:27261181

  17. SACALC2B

    2007-02-08

    SACALC2B calculates the average solid angle subtended by a rectangular or circular detector window to a coaxial or non-coaxial rectangular, circular or point source, including where the source and detector planes are not parallel. SACALC_CYL calculates the average solid angle subtended by a cylinder to a rectangular or circular source, plane or thick, at any location and orientation. This is needed, for example, in calculating the intrinsic gamma efficiency of a detector such as amore » GM tube. The program also calculates the number of hits on the cylinder side and on each end, and the average path length through the detector volume (assuming no scattering or absorption). Point sources can be modelled by using a circular source of zero radius.« less

  18. High EGFR_1 Inside-Out Activated Inflammation-Induced Motility through SLC2A1-CCNB2-HMMR-KIF11-NUSAP1-PRC1-UBE2C.

    PubMed

    Zhou, Huilei; Wang, Lin; Huang, Juxiang; Jiang, Minghu; Zhang, Xiaoyu; Zhang, Liyuan; Wang, Yangming; Jiang, Zhenfu; Zhang, Zhongjie

    2015-01-01

    48 different Pearson mutual-positive-correlation epidermal growth factor receptor (EGFR_1)-activatory molecular feedback, up- and down-stream network was constructed from 171 overlapping of 366 GRNInfer and 223 Pearson under EGFR_1 CC ≥0.25 in high lung adenocarcinoma compared with low human normal adjacent tissues. Our identified EGFR_1 inside-out upstream activated molecular network showed SLC2A1 (solute carrier family 2 (facilitated glucose transporter) member 1), CCNB2 (cyclin B2), HMMR (hyaluronan-mediated motility receptor (RHAMM)), KIF11 (kinesin family member 11), NUSAP1 (nucleolar and spindle associated protein 1), PRC1 (protein regulator of cytokinesis 1), UBE2C (ubiquitin-conjugating enzyme E2C) in high lung adenocarcinoma. EGFR_1 inside-out upstream activated terms network includes intracellular, membrane fraction, cytoplasm, plasma membrane, integral to membrane, basolateral plasma membrane, transmembrane transport, nucleus, cytosol, cell surface; T cell homeostasis, inflammation; microtubule cytoskeleton, embryonic development (sensu Mammalia), cell cycle, mitosis, thymus development, cell division, regulation of cell cycle, Contributed--cellular process--Hs cell cycle KEGG, cytokinesis, M phase, M phase of mitotic cell cycle, estrogen-responsive protein Efp controls cell cycle and breast tumors growth, cell motility, locomotion, locomotory behavior, neoplasm metastasis, spindle pole, spindle microtubule, microtubule motor activity, microtubule-based movement, mitotic spindle organization and biogenesis, mitotic centrosome separation, spindle pole body organization and biogenesis, microtubule-based process, microtubule, cytokinesis after mitosis, mitotic chromosome condensation, establishment of mitotic spindle localization, positive regulation of mitosis, mitotic spindle elongation, spindle organization and biogenesis, positive regulation of exit from mitosis, regulation of cell proliferation, positive regulation of cell proliferation based on

  19. Enhanced phagocytic activity of HIV-specific antibodies correlates with natural production of immunoglobulins with skewed affinity for FcγR2a and FcγR2b.

    PubMed

    Ackerman, Margaret E; Dugast, Anne-Sophie; McAndrew, Elizabeth G; Tsoukas, Stephen; Licht, Anna F; Irvine, Darrell J; Alter, Galit

    2013-05-01

    While development of an HIV vaccine that can induce neutralizing antibodies remains a priority, decades of research have proven that this is a daunting task. However, accumulating evidence suggests that antibodies with the capacity to harness innate immunity may provide some protection. While significant research has focused on the cytolytic properties of antibodies in acquisition and control, less is known about the role of additional effector functions. In this study, we investigated antibody-dependent phagocytosis of HIV immune complexes, and we observed significant differences in the ability of antibodies from infected subjects to mediate this critical effector function. We observed both quantitative differences in the capacity of antibodies to drive phagocytosis and qualitative differences in their FcγR usage profile. We demonstrate that antibodies from controllers and untreated progressors exhibit increased phagocytic activity, altered Fc domain glycosylation, and skewed interactions with FcγR2a and FcγR2b in both bulk plasma and HIV-specific IgG. While increased phagocytic activity may directly influence immune activation via clearance of inflammatory immune complexes, it is also plausible that Fc receptor usage patterns may regulate the immune response by modulating downstream signals following phagocytosis--driving passive degradation of internalized virus, release of immune modulating cytokines and chemokines, or priming of a more effective adaptive immune response.

  20. Molecular breeding for introgression of fatty acid desaturase mutant alleles (ahFAD2A and ahFAD2B) enhances oil quality in high and low oil containing peanut genotypes.

    PubMed

    Janila, Pasupuleti; Pandey, Manish K; Shasidhar, Yaduru; Variath, Murali T; Sriswathi, Manda; Khera, Pawan; Manohar, Surendra S; Nagesh, Patne; Vishwakarma, Manish K; Mishra, Gyan P; Radhakrishnan, T; Manivannan, N; Dobariya, K L; Vasanthi, R P; Varshney, Rajeev K

    2016-01-01

    High oleate peanuts have two marketable benefits, health benefits to consumers and extended shelf life of peanut products. Two mutant alleles present on linkage group a09 (ahFAD2A) and b09 (ahFAD2B) control composition of three major fatty acids, oleic, linoleic and palmitic acids which together determine peanut oil quality. In conventional breeding, selection for fatty acid composition is delayed to advanced generations. However by using DNA markers, breeders can reject large number of plants in early generations and therefore can optimize time and resources. Here, two approaches of molecular breeding namely marker-assisted backcrossing (MABC) and marker-assisted selection (MAS) were employed to transfer two FAD2 mutant alleles from SunOleic 95R into the genetic background of ICGV 06110, ICGV 06142 and ICGV 06420. In summary, 82 MABC and 387 MAS derived introgression lines (ILs) were developed using DNA markers with elevated oleic acid varying from 62 to 83%. Oleic acid increased by 0.5-1.1 folds, with concomitant reduction of linoleic acid by 0.4-1.0 folds and palmitic acid by 0.1-0.6 folds among ILs compared to recurrent parents. Finally, high oleate ILs, 27 with high oil (53-58%), and 28 ILs with low oil content (42-50%) were selected that may be released for cultivation upon further evaluation. PMID:26566838

  1. New hepatitis C virus (HCV) genotyping system that allows for identification of HCV genotypes 1a, 1b, 2a, 2b, 3a, 3b, 4, 5a, and 6a.

    PubMed Central

    Ohno, O; Mizokami, M; Wu, R R; Saleh, M G; Ohba, K; Orito, E; Mukaide, M; Williams, R; Lau, J Y

    1997-01-01

    Recent studies have focused on whether different hepatitis C virus (HCV) genotypes are associated with different profiles of pathogenicity, infectivity, and response to antiviral therapy. The establishment of a simple and precise genotyping system for HCV is essential to address these issues. A new genotyping system based on PCR of the core region with genotype-specific PCR primers for the determination of HCV genotypes 1a, 1b, 2a, 2b, 3a, 3b, 4, 5a, and 6a was developed. A total of 607 samples (379 from Japan, 63 from the United States, 53 from Korea, 35 from Taiwan, 32 from China, 20 from Hong Kong, 15 from Australia, 6 from Egypt, 3 from Bangladesh, and 1 from South Africa) were tested by both the assay of Okamoto et al. (H. Okamoto, Y. Sugiyama, S. Okada, K. Kurai, Y. Akahane, Y. Sugai, T. Tanaka, K. Sato, F. Tsuda, Y. Miyamura, and M. Mayumi, J. Gen. Virol. 73:673-679, 1992) and this new genotyping system. Comparison of the results showed concordant results for 539 samples (88.8%). Of the 68 samples with discordant results, the nucleotide sequences of the HCV isolates were determined in 23, and their genotypes were determined by molecular evolutionary analysis. In all 23 samples, the assignment of genotype by our new genotyping system was correct. This genotyping system may be useful for large-scale determination of HCV genotypes in clinical studies. PMID:8968908

  2. Clonidine potentiates the effects of 5-HT1A, 5-HT1B and 5-HT2A/2C antagonists and 8-OH-DPAT in the mouse forced swimming test.

    PubMed

    Redrobe, J P; Bourin, M

    1998-08-01

    The present study was undertaken to identify the receptor subtypes involved in clonidine's ability to enhance the effects of antidepressant drugs in the mouse forced swimming test. Clonidine (0.06 mg/kg, i.p.) significantly enhanced the antidepressant-like effects of subactive doses of the 5-HT1A receptor agonist, 8-OH-DPAT (1 mg/kg, i.p.; P<0.01); the 5-HT1A receptor antagonist, NAN 190 (0.5 mg/kg, i.p.; P<0.01); the 5-HT1A/1B autoreceptor antagonist, (+/-) pindolol (32 mg/kg, i.p.; P<0.01); the 5-HT2A/2C receptor antagonist, ritanserin (4 mg/kg, i.p.; P<0.01). Pretreatment with clonidine failed to increase mobility when administered in combination with the 5-HT1B receptor agonist, RU 24969 (1 mg/kg, i.p.) or the 5-HT2A receptor antagonist, ketanserin (8 mg/kg, i.p.). In conclusion, clonidine-induced anti-immobility effects are more likely mediated by 5-HT1A and 5-HT2C receptors, as well as alpha-2-adrenergic autoreceptors situated on noradrenergic neurones. The results of the present study also demonstrate that serotonergic receptor function can influence alpha-2-adrenoreceptor mediated responses in the mouse forced swimming test.

  3. The expression profile of acid-sensing ion channel (ASIC) subunits ASIC1a, ASIC1b, ASIC2a, ASIC2b, and ASIC3 in the esophageal vagal afferent nerve subtypes

    PubMed Central

    Dusenkova, Svetlana; Ru, Fei; Surdenikova, Lenka; Nassenstein, Christina; Hatok, Jozef; Dusenka, Robert; Banovcin, Peter; Kliment, Jan; Tatar, Milos

    2014-01-01

    Acid-sensing ion channels (ASICs) have been implicated in esophageal acid sensing and mechanotransduction. However, insufficient knowledge of ASIC subunit expression profile in esophageal afferent nerves hampers the understanding of their role. This knowledge is essential because ASIC subunits form heteromultimeric channels with distinct functional properties. We hypothesized that the esophageal putative nociceptive C-fiber nerves (transient receptor potential vanilloid 1, TRPV1-positive) express multiple ASIC subunits and that the ASIC expression profile differs between the nodose TRPV1-positive subtype developmentally derived from placodes and the jugular TRPV1-positive subtype derived from neural crest. We performed single cell RT-PCR on the vagal afferent neurons retrogradely labeled from the esophagus. In the guinea pig, nearly all (90%–95%) nodose and jugular esophageal TRPV1-positive neurons expressed ASICs, most often in a combination (65–75%). ASIC1, ASIC2, and ASIC3 were expressed in 65–75%, 55–70%, and 70%, respectively, of both nodose and jugular TRPV1-positive neurons. The ASIC1 splice variants ASIC1a and ASIC1b and the ASIC2 splice variant ASIC2b were similarly expressed in both nodose and jugular TRPV1-positive neurons. However, ASIC2a was found exclusively in the nodose neurons. In contrast to guinea pig, ASIC3 was almost absent from the mouse vagal esophageal TRPV1-positive neurons. However, ASIC3 was similarly expressed in the nonnociceptive TRPV1-negative (tension mechanoreceptors) neurons in both species. We conclude that the majority of esophageal vagal nociceptive neurons express multiple ASIC subunits. The placode-derived nodose neurons selectively express ASIC2a, known to substantially reduce acid sensitivity of ASIC heteromultimers. ASIC3 is expressed in the guinea pig but not in the mouse vagal esophageal TRPV1-positive neurons, indicating species differences in ASIC expression. PMID:25190475

  4. Chemical understanding of carbide cluster metallofullerenes: a case study on Sc2C2@C2v(5)-C80 with complete X-ray crystallographic characterizations.

    PubMed

    Kurihara, Hiroki; Lu, Xing; Iiduka, Yuko; Nikawa, Hidefumi; Mizorogi, Naomi; Slanina, Zdenek; Tsuchiya, Takahiro; Nagase, Shigeru; Akasaka, Takeshi

    2012-02-15

    Little is known about the chemical properties of carbide cluster metallofullerenes (CCMFs). Here we report the photochemical reaction of a newly assigned CCMF Sc(2)C(2)@C(2v)(5)-C(80) with 2-adamantane-2,3-[3H]-diazirine (AdN(2), 1), which provides a carbene reagent under irradiation. Five monoadduct isomers (2a-2e), with respective abundances of 20%, 40%, 25%, 5%, and 10%, were isolated and characterized with a combination of experimental techniques including unambiguous single-crystal X-ray crystallography. Results show that the two Sc atoms of the bent Sc(2)C(2) cluster tend to move in most cases, whereas the C(2)-unit is almost fixed. Accordingly, it is difficult to explain the addition patterns by considering the strain and charge density on the cage with a fixed cluster, and thus a moving cluster may account for the addition patterns. These results show that the situation of CCMFs is more complicated than those in other metallofullerenes. Furthermore, a thermal isomerization process from 2b to 2c was observed, confirming that the most abundant isomer 2b is a kinetically favored adduct. Finally, it is revealed that the electronic and electrochemical properties of pristine Sc(2)C(2)@C(2v)(5)-C(80) have been markedly altered by exohedral modification.

  5. Support for 5-HT2C receptor functional selectivity in vivo utilizing structurally diverse, selective 5-HT2C receptor ligands and the 2,5-dimethoxy-4-iodoamphetamine elicited head-twitch response model

    PubMed Central

    Canal, Clinton E.; Booth, Raymond G.; Morgan, Drake

    2013-01-01

    There are seemingly conflicting data in the literature regarding the role of serotonin (5-HT) 5-HT2C receptors in the mouse head-twitch response (HTR) elicited by the hallucinogenic 5-HT2A/2B/2C receptor agonist 2,5-dimethoxy-4-iodoamphetamine (DOI). Namely, both 5-HT2C receptor agonists and antagonists, regarding 5-HT2C receptor-mediated Gq-phospholipase C (PLC) signaling, reportedly attenuate the HTR response. The present experiments tested the hypothesis that both classes of 5-HT2C receptor compounds could attenuate the DOI-elicited-HTR in a single strain of mice, C57Bl/6J. The expected results were considered in accordance with ligand functional selectivity. Commercially-available 5-HT2C agonists (CP 809101, Ro 60-0175, WAY 161503, mCPP, and 1-methylpsilocin), novel 4-phenyl-2-N,N-dimethyl-aminotetralin (PAT)-type 5-HT2C agonists (with 5-HT2A/2B antagonist activity), and antagonists selective for 5-HT2A (M100907), 5-HT2C (SB-242084), and 5-HT2B/2C (SB-206553) receptors attenuated the DOI-elicited-HTR. In contrast, there were differential effects on locomotion across classes of compounds. The 5-HT2C agonists and M100907 decreased locomotion, SB-242084 increased locomotion, SB-206553 resulted in dose-dependent biphasic effects on locomotion, and the PATs did not alter locomotion. In vitro molecular pharmacology studies showed that 5-HT2C agonists potent for attenuating the DOI-elicited-HTR also reduced the efficacy of DOI to activate mouse 5-HT2C receptor-mediated PLC signaling in HEK cells. Although there were differences in affinities of a few compounds at mouse compared to human 5-HT2A or 5-HT2C receptors, all compounds tested retained their selectivity for either receptor, regardless of receptor species. Results indicate that 5-HT2C receptor agonists and antagonists attenuate the DOI-elicited-HTR in C57Bl/6J mice, and suggest that structurally diverse 5-HT2C ligands result in different 5-HT2C receptor signaling outcomes compared to DOI. PMID:23353901

  6. Effects of central activation of serotonin 5-HT2A/2C or dopamine D2/3 receptors on the acute and repeated effects of clozapine in the conditioned avoidance response test

    PubMed Central

    Feng, Min; Gao, Jun; Sui, Nan; Li, Ming

    2014-01-01

    Rationale: Acute administration of clozapine (a gold standard of atypical antipsychotics) disrupts avoidance response in rodents, while repeated administration often causes a tolerance effect. Objective: The present study investigated the neuroanatomical basis and receptor mechanisms of acute and repeated effects of clozapine treatment in the conditioned avoidance response test in male Sprague-Dawley rats. Methods: DOI (2,5-dimethoxy-4-iodo-amphetamine, a preferential 5-HT2A/2C agonist) or quinpirole (a preferential dopamine D2/3 agonist) was microinjected into the medial prefrontal cortex (mPFC) or nucleus accumbens shell (NAs), and their effects on the acute and long-term avoidance-disruptive effect of clozapine were tested. Results: Intra-mPFC microinjection of quinpirole enhanced the acute avoidance disruptive effect of clozapine (10 mg/kg, sc), while DOI microinjections reduced it marginally. Repeated administration of clozapine (10 mg/kg, sc) daily for 5 days caused a progressive decrease in its inhibition of avoidance responding, indicating tolerance development. Intra-mPFC microinjection of DOI at 25.0 (but not 5.0) μg/side during this period completely abolished the expression of clozapine tolerance. This was indicated by the finding that clozapine-treated rats centrally infused with 25.0 μg/side DOI did not show higher levels of avoidance responses than the vehicle-treated rats in the clozapine challenge test. Microinjection of DOI into the mPFC immediately before the challenge test also decreased the expression of clozapine tolerance. Conclusions: Acute behavioral effect of clozapine can be enhanced by activation of the D2/3 receptors in the mPFC. Clozapine tolerance expression relies on the neuroplasticity initiated by its antagonist action against 5-HT2A/2C receptors in the mPFC. PMID:25288514

  7. Serum from patients with systemic vasculitis induces alternatively activated macrophage M2c polarization.

    PubMed

    Ohlsson, Susanne M; Linge, Carl Petrus; Gullstrand, Birgitta; Lood, Christian; Johansson, Asa; Ohlsson, Sophie; Lundqvist, Andrea; Bengtsson, Anders A; Carlsson, Fredric; Hellmark, Thomas

    2014-01-01

    Anti-neutrophil cytoplasmic antibody associated vasculitides (AAV) are conditions defined by an autoimmune small vessel inflammation. Dying neutrophils are found around the inflamed vessels and the balance between infiltrating neutrophils and macrophages is important to prevent autoimmunity. Here we investigate how sera from AAV patients may regulate macrophage polarization and function. Macrophages from healthy individuals were differentiated into M0, M1, M2a, M2b or M2c macrophages using a standardized protocol, and phenotyped according to their expression surface markers and cytokine production. These phenotypes were compared with those of macrophages stimulated with serum from AAV patients or healthy controls. While the healthy control sera induced a M0 macrophage, AAV serum promoted polarization towards the M2c subtype. No sera induced M1, M2a or M2b macrophages. The M2c subtype showed increased phagocytosis capacity compared with the other subtypes. The M2c polarization found in AAV is consistent with previous reports of increased levels of M2c-associated cytokines.

  8. CYP2C subfamily, primarily CYP2C9, catalyses the enantioselective demethylation of the endocrine disruptor pesticide methoxychlor in human liver microsomes: use of inhibitory monoclonal antibodies in P450 identification.

    PubMed

    Hu, Y; Krausz, K; Gelboin, H V; Kupfer, D

    2004-02-01

    1. The endocrine disruptor pesticide methoxychlor undergoes O-demethylation by mammalian liver microsomes forming chiral mono-phenolic (1,1,1-trichloro-2-(4-hydroxyphenyl)-2-(4-methoxyphenyl)ethane, i.e. mono-OH-M) and achiral bis-phenolic oestrogenic metabolites. Human liver microsomes (HLM) generated primarily the S-mono-OH-M. 2. Inhibitory monoclonal antibodies (MAb) identified those P450s catalysing the enantioselective O-demethylation of methoxychlor. In HLM, O-demethylation was inhibited by MAb anti-2C9 (30-40%), diminishing the per cent of S-mono-OH-M from about 80 to 55-60%. MAb anti-CYP1A2, 2A6, 2B6, 2C8, 2C19, 2D6 and 3A4 did not affect the demethylation rate in HLM. Nevertheless, MAb anti-CYP1A2 decreased the formation of R-mono-OH-M from 21-23 to 10-17%, indicating that CYP1A2 exhibits a role in generating the R-enantiomer. 3. Among cDNA-expressed human P450s (supersomes), CYP2C19 was the most active in demethylation, but in HLM, CYP2C19 appeared inactive (no inhibition by MAb anti-CYP2C19). There was a substantial difference in the per cent inhibition of demethylation by MAb anti-CYP2C9 and anti-rat CYP2C (MAb inhibiting all human CYP2C forms) and in altering the enantioselectivity, suggesting that demethylation by combined CYP2C8, 2C18 and 2C19 was significant (20-30%). 4. Polymorphism of methoxychlor demethylation was examined with supersomes and HLM-expressing CYP2C9 allelic variants. CYP2C9*1 and 2C9*2 were highly active; however, CYP2C9*3 appeared inactive.

  9. Optimization of 2-phenylcyclopropylmethylamines as selective serotonin 2C receptor agonists and their evaluation as potential antipsychotic agents.

    PubMed

    Cheng, Jianjun; Giguère, Patrick M; Onajole, Oluseye K; Lv, Wei; Gaisin, Arsen; Gunosewoyo, Hendra; Schmerberg, Claire M; Pogorelov, Vladimir M; Rodriguiz, Ramona M; Vistoli, Giulio; Wetsel, William C; Roth, Bryan L; Kozikowski, Alan P

    2015-02-26

    The discovery of a new series of compounds that are potent, selective 5-HT2C receptor agonists is described herein as we continue our efforts to optimize the 2-phenylcyclopropylmethylamine scaffold. Modifications focused on the alkoxyl substituent present on the aromatic ring led to the identification of improved ligands with better potency at the 5-HT2C receptor and excellent selectivity against the 5-HT2A and 5-HT2B receptors. ADMET studies coupled with a behavioral test using the amphetamine-induced hyperactivity model identified four compounds possessing drug-like profiles and having antipsychotic properties. Compound (+)-16b, which displayed an EC50 of 4.2 nM at 5-HT2C, no activity at 5-HT2B, and an 89-fold selectivity against 5-HT2A, is one of the most potent and selective 5-HT2C agonists reported to date. The likely binding mode of this series of compounds to the 5-HT2C receptor was also investigated in a modeling study, using optimized models incorporating the structures of β2-adrenergic receptor and 5-HT2B receptor. PMID:25633969

  10. Synthesis and chemistry of the open-cage cobaltaheteroborane cluster [{(η(5)-C5Me5)Co}2B2H2Se2]: a combined experimental and theoretical study.

    PubMed

    Barik, Subrat Kumar; Dorcet, Vincent; Roisnel, Thierry; Halet, Jean-François; Ghosh, Sundargopal

    2015-08-28

    Reaction of [(η(5)-C5Me5)CoCl]2 with a two-fold excess of [LiBH4·thf] followed by heating with an excess of Se powder produces the dicobaltaselenaborane species [{(η(5)-C5Me5)Co}2B2H2Se2], , in good yield. The geometry of resembles a nido pentagonal [Co2B2Se2] bipyramid with a missing equatorial vertex. It can alternatively be seen as an open cage triple-decker cluster. Isolation of permits its reaction with [Fe2(CO)9] to give heterometallic diselenametallaborane [{(η(5)-C5Me5)Co}Fe(CO)3B2H2Se2], . The geometry of is similar to that of with one of the [(η(5)-C5Me5)Co] groups replaced by the isolobal, two-electron fragment [Fe(CO)3]. Both new compounds have been characterized by mass spectrometry, and by (1)H, (11)B and (13)C NMR spectroscopy. The structural architectures have been unequivocally established by crystallographic analysis. In addition, density functional theory calculations were performed to investigate the bonding and electronic properties. The large HOMO-LUMO gaps computed for both clusters are consistent with their thermodynamic stability. Natural bond order calculations predict the absence of metal-metal bonding interaction. PMID:26200318

  11. Pancreatic Cancer Stage 2B

    MedlinePlus

    ... 2B Description: Stage IIB pancreatic cancer; drawing shows cancer in the pancreas and in nearby lymph nodes. Also shown are the bile duct, pancreatic duct, and duodenum. Stage IIB pancreatic cancer. Cancer has spread to nearby lymph nodes and ...

  12. Extending David Horrobin's membrane phospholipid theory of schizophrenia: overactivity of cytosolic phospholipase A(2) in the brain is caused by overdrive of coupled serotonergic 5HT(2A/2C) receptors in response to stress.

    PubMed

    Eggers, Arnold E

    2012-12-01

    David Horrobin's membrane phospholipid theory of schizophrenia has held up well over time because his therapeutic prediction that dietary supplementation with eicosapentaenoic acid (EPA) would have a therapeutic effect has been partially verified and undergoes continued testing. In the final version of his theory, he hypothesized that there was hyperactivity of phosphoslipase A(2) (PLA(2)) or a related enzyme but did not explain how the hyperactivity came about. It is known that serotonergic 5HT(2A/2C) receptors are coupled to PLA(2), which hydrolyzes both arachidonic acid (AA) and EPA from diacylglycerides at the sn-2 position. In this paper, Horrobin's theory is combined with a previously published theory of chronic stress in which it was hypothesized that a disinhibited dorsal raphe nucleus, the principal nucleus of the serotonergic system, can organize the neuropathology of diseases such as migraine, hypertension, and the metabolic syndrome. The new or combined theory is that schizophrenia is a disease of chronic stress in which a disinhibited DRN causes widespread serotonergic overdrive in the cerebral cortex. This in turn causes overdrive of cPLA(2) and both central and peripheral depletion of AA and EPA. Because EPA is present in smaller amounts, it falls below threshold for maintaining an intracellular balance between AA-derived and EPA-derived second messenger cascades, which leads to abnormal patterns of neuronal firing. There are two causes of neuronal dysfunction: the disinhibited DRN and EPA depletion. Schizophrenia is statistically associated with metabolic syndrome, hypertension, and migraine because they form a cluster of diseases with similar pathophysiology. The theory provides an explanation for both the central and peripheral phospholipid abnormalities in schizophrenia. It also explains the role of stress in schizophrenia, elevated serum PLA(2) activity in schizophrenia, the relationship between untreated schizophrenia and metabolic syndrome

  13. Molecular characterization of canine parvovirus strains in Argentina: Detection of the pathogenic variant CPV2c in vaccinated dogs.

    PubMed

    Calderon, Marina Gallo; Mattion, Nora; Bucafusco, Danilo; Fogel, Fernando; Remorini, Patricia; La Torre, Jose

    2009-08-01

    PCR amplification with sequence-specific primers was used to detect canine parvovirus (CPV) DNA in 38 rectal swabs from Argentine domestic dogs with symptoms compatible with parvovirus disease. Twenty-seven out of 38 samples analyzed were CPV positive. The classical CPV2 strain was not detected in any of the samples, but nine samples were identified as CPV2a variant and 18 samples as CPV2b variant. Further sequence analysis revealed a mutation at amino acid 426 of the VP2 gene (Asp426Glu), characteristic of the CPV2c variant, in 14 out of 18 of the samples identified initially by PCR as CPV2b. The appearance of CPV2c variant in Argentina might be dated at least to the year 2003. Three different pathogenic CPV variants circulating currently in the Argentine domestic dog population were identified, with CPV2c being the only variant affecting vaccinated and unvaccinated dogs during the year 2008.

  14. Materials Data on GdNi2B2C (SG:139) by Materials Project

    DOE Data Explorer

    Kristin Persson

    2014-07-09

    Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations

  15. Materials Data on PrCo2B2C (SG:139) by Materials Project

    SciTech Connect

    Kristin Persson

    2014-11-02

    Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations

  16. Materials Data on CeNi2B2C (SG:139) by Materials Project

    SciTech Connect

    Kristin Persson

    2015-02-09

    Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations

  17. Materials Data on EuNi2B2C (SG:139) by Materials Project

    SciTech Connect

    Kristin Persson

    2014-07-09

    Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations

  18. Materials Data on Cu2B2C (SG:12) by Materials Project

    SciTech Connect

    Kristin Persson

    2014-09-30

    Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations

  19. LAMP-2C Inhibits MHC Class II Presentation of Cytoplasmic Antigens by Disrupting Chaperone-Mediated Autophagy.

    PubMed

    Pérez, Liliana; McLetchie, Shawna; Gardiner, Gail J; Deffit, Sarah N; Zhou, Delu; Blum, Janice S

    2016-03-15

    Cells use multiple autophagy pathways to sequester macromolecules, senescent organelles, and pathogens. Several conserved isoforms of the lysosome-associated membrane protein-2 (LAMP-2) regulate these pathways influencing immune recognition and responses. LAMP-2A is required for chaperone-mediated autophagy (CMA), which promotes Ag capture and MHC class II (MHCII) presentation in B cells and signaling in T cells. LAMP-2B regulates lysosome maturation to impact macroautophagy and phagocytosis. Yet, far less is known about LAMP-2C function. Whereas LAMP2A and LAMP2B mRNA were broadly detected in human tissues, LAMP2C expression was more limited. Transcripts for the three LAMP2 isoforms increased with B cell activation, although specific gene induction varied depending on TLR versus BCR engagement. To examine LAMP-2C function in human B cells and specifically its role in Ag presentation, we used ectopic gene expression. Increased LAMP-2C expression in B cells did not alter MHCII expression or invariant chain processing, but did perturb cytoplasmic Ag presentation via CMA. MHCII presentation of epitopes from exogenous and membrane Ags was not affected by LAMP-2C expression in B cells. Similarly, changes in B cell LAMP-2C expression did not impact macroautophagy. The gene expression of other LAMP2 isoforms and proteasome and lysosomal proteases activities were unperturbed by LAMP-2C ectopic expression. LAMP-2C levels modulated the steady-state expression of several cytoplasmic proteins that are targeted for degradation by CMA and diminished peptide translocation via this pathway. Thus, LAMP-2C serves as a natural inhibitor of CMA that can selectively skew MHCII presentation of cytoplasmic Ags. PMID:26856698

  20. Gene variants in CYP2C19 are associated with altered in vivo bupropion pharmacokinetics but not bupropion-assisted smoking cessation outcomes.

    PubMed

    Zhu, Andy Z X; Zhou, Qian; Cox, Lisa Sanderson; Ahluwalia, Jasjit S; Benowitz, Neal L; Tyndale, Rachel F

    2014-11-01

    Bupropion is used clinically to treat depression and to promote smoking cessation. It is metabolized by CYP2B6 to its active metabolite hydroxybupropion, yet alterations in CYP2B6 activity have little impact on bupropion plasma levels. Furthermore, less than 10% of a bupropion dose is excreted as urinary bupropion and its characterized metabolites hydroxybupropion, threohydrobupropion, and erythrohydrobupropion, suggesting that alternative metabolic pathways may exist. In vitro data suggested CYP2C19 could metabolize bupropion. The current study investigated the impact of functional CYP2C19 genetic variants on bupropion pharmacokinetics and treatment outcomes. In 42 healthy volunteers, CYP2C19*2 (a reduced activity allele) was associated with higher bupropion area under the plasma concentration-time curve (AUC), but similar hydroxybupropion AUC. The mean bupropion AUC was 771 versus 670 hours⋅ng/ml in individuals with and without CYP2C19*2, respectively (P = 0.017). CYP2C19*2 was also associated with higher threohydrobupropion and erythrohydrobupropion AUC (P < 0.005). Adjusting for CYP2B6 genotype did not alter these associations, and CYP2C19 variants did not alter the utility of the hydroxybupropion/bupropion ratio as a measure of CYP2B6 activity. Finally, in a clinical trial of 540 smokers, CYP2C19 genotype was not associated with smoking cessation outcomes, supporting the hypothesis that bupropion response is mediated by hydroxybupropion, which is not altered by CYP2C19. In conclusion, our study reports the first in vivo evidence that reduced CYP2C19 activity significantly increases the steady-state exposure to bupropion and its reductive metabolites threohydrobupropion and erythrohydrobupropion. These pharmacokinetic changes were not associated with differences in bupropion's ability to promote smoking cessation in smokers, but may influence the side effects and toxicity associated with bupropion.

  1. ADORA2b Signaling in Cardioprotection

    PubMed Central

    Gile, Jennifer; Eckle, Tobias

    2016-01-01

    Cardiovascular disease is the number one cause of death worldwide. A powerful strategy for cardioprotection would be to identify specific molecules or targets that mimic ischemic preconditioning (IP), where short non-lethal episodes of ischemia and reperfusion prior to myocardial infarction result in dramatic reduction of infarct sizes. Since 1960 researchers believed that adenosine has a strong cardio-protective potential. In fact, with the discovery of cardiac IP in 1986 by Murry et al., adenosine was the first identified molecule that was used in studying the underlying mechanism of IP. Today we know, based on genetic studies, that adenosine is crucial for IP mediated cardio-protection and that the adenosine receptors ADORA1, ADORA2a and ADORA2b play an important role. However, the ADORA2b receptor is the only receptor so far which has been found to play a role in human and murine myocardial ischemia. With recent advances using tissue specific mice for the ADORA2b, we were able to uncover cardiomyocytes and endothelia as the responsible cell type for cardiac IP. Using a wide search for ADORA2b downstream targets, our group identified the circadian rhythm protein, Period 2 (PER2), as a novel target for IP mediated cardioprotection. Mechanistic studies on PER2 mediated cardioprotection revealed an important role for PER2 in optimizing cardiac metabolism through activation of oxygen saving pathways. Thus, cardiomyocyte or endothelial expressed ADORA2b or the downstream circadian rhythm protein PER2 are key targets for cardiac IP and could represent novel strategies to treat or prevent MI.

  2. Evolution of canine parvovirus in Argentina between years 2003 and 2010: CPV2c has become the predominant variant affecting the domestic dog population.

    PubMed

    Calderón, Marina Gallo; Romanutti, Carina; D' Antuono, Alejandra; Keller, Leticia; Mattion, Nora; La Torre, Jose

    2011-04-01

    The current frequency of Canine Parvovirus variants (CPV2a, CPV2b and CPV2c) in the Argentine dog population was investigated by PCR amplification of a 583 bp fragment in the VP2 gene. From a total of 79 rectal swab samples that have been submitted to our laboratory since 2008, 55 (69.6%) resulted positive and were further analyzed by direct DNA sequencing. Fifty positives samples (91%) were characterized as CPV2c variant, which appeared in Argentina in the year 2003 and has been the prevalent type since 2008, whereas CPV2a and CPV2b, still found in Argentine dogs, were represented in 3.6% and 5.4% of the population, respectively. Considering that CPV2c is spreading worldwide, and that this variant is also affecting vaccinated dogs, efforts should be made towards the development of new matched CPV vaccines. PMID:21354224

  3. Evolution of canine parvovirus in Argentina between years 2003 and 2010: CPV2c has become the predominant variant affecting the domestic dog population.

    PubMed

    Calderón, Marina Gallo; Romanutti, Carina; D' Antuono, Alejandra; Keller, Leticia; Mattion, Nora; La Torre, Jose

    2011-04-01

    The current frequency of Canine Parvovirus variants (CPV2a, CPV2b and CPV2c) in the Argentine dog population was investigated by PCR amplification of a 583 bp fragment in the VP2 gene. From a total of 79 rectal swab samples that have been submitted to our laboratory since 2008, 55 (69.6%) resulted positive and were further analyzed by direct DNA sequencing. Fifty positives samples (91%) were characterized as CPV2c variant, which appeared in Argentina in the year 2003 and has been the prevalent type since 2008, whereas CPV2a and CPV2b, still found in Argentine dogs, were represented in 3.6% and 5.4% of the population, respectively. Considering that CPV2c is spreading worldwide, and that this variant is also affecting vaccinated dogs, efforts should be made towards the development of new matched CPV vaccines.

  4. Structural Basis for Host Membrane Remodeling Induced by Protein 2B of Hepatitis A Virus

    PubMed Central

    Vives-Adrián, Laia; Garriga, Damià; Buxaderas, Mònica; Fraga, Joana; Pereira, Pedro José Barbosa

    2015-01-01

    ABSTRACT The complexity of viral RNA synthesis and the numerous participating factors require a mechanism to topologically coordinate and concentrate these multiple viral and cellular components, ensuring a concerted function. Similarly to all other positive-strand RNA viruses, picornaviruses induce rearrangements of host intracellular membranes to create structures that act as functional scaffolds for genome replication. The membrane-targeting proteins 2B and 2C, their precursor 2BC, and protein 3A appear to be primarily involved in membrane remodeling. Little is known about the structure of these proteins and the mechanisms by which they induce massive membrane remodeling. Here we report the crystal structure of the soluble region of hepatitis A virus (HAV) protein 2B, consisting of two domains: a C-terminal helical bundle preceded by an N-terminally curved five-stranded antiparallel β-sheet that displays striking structural similarity to the β-barrel domain of enteroviral 2A proteins. Moreover, the helicoidal arrangement of the protein molecules in the crystal provides a model for 2B-induced host membrane remodeling during HAV infection. IMPORTANCE No structural information is currently available for the 2B protein of any picornavirus despite it being involved in a critical process in viral factory formation: the rearrangement of host intracellular membranes. Here we present the structure of the soluble domain of the 2B protein of hepatitis A virus (HAV). Its arrangement, both in crystals and in solution under physiological conditions, can help to understand its function and sheds some light on the membrane rearrangement process, a putative target of future antiviral drugs. Moreover, this first structure of a picornaviral 2B protein also unveils a closer evolutionary relationship between the hepatovirus and enterovirus genera within the Picornaviridae family. PMID:25589659

  5. Using msa-2b as a molecular marker for genotyping Mexican isolates of Babesia bovis.

    PubMed

    Genis, Alma D; Perez, Jocelin; Mosqueda, Juan J; Alvarez, Antonio; Camacho, Minerva; Muñoz, Maria de Lourdes; Rojas, Carmen; Figueroa, Julio V

    2009-12-01

    Variable merozoite surface antigens of Babesia bovis are exposed glycoproteins having a role in erythrocyte invasion. Members of this gene family include msa-1 and msa-2 (msa-2c, msa-2a(1), msa-2a(2) and msa-2b). To determine the sequence variation among B. bovis Mexican isolates using msa-2b as a genetic marker, PCR amplicons corresponding to msa-2b were cloned and plasmids carrying the corresponding inserts were purified and sequenced. Comparative analysis of nucleotide and deduced amino acid sequences revealed distinct degrees of variability and identity among the coding gene sequences obtained from 16 geographically different Mexican B. bovis isolates and a reference strain. Clustal-W multiple alignments of the MSA-2b deduced amino acid sequences performed with the 17 B. bovis Mexican isolates, revealed the identification of three genotypes with a distinct set each of amino acid residues present at the variable region: Genotype I represented by the MO7 strain (in vitro culture-derived from the Mexico isolate) as well as RAD, Chiapas-1, Tabasco and Veracruz-3 isolates; Genotype II, represented by the Jalisco, Mexico and Veracruz-2 isolates; and Genotype III comprising the sequences from most of the isolates studied, Tamaulipas-1, Chiapas-2, Guerrero-1, Nayarit, Quintana Roo, Nuevo Leon, Tamaulipas-2, Yucatan and Guerrero-2. Moreover, these three genotypes could be discriminated against each other by using a PCR-RFLP approach. The results suggest that occurrence of indels within the variable region of msa-2b sequences can be useful markers for identifying a particular genotype present in field populations of B. bovis isolated from infected cattle in Mexico.

  6. Ca2+-ATPases in non-failing and failing heart: evidence for a novel cardiac sarco/endoplasmic reticulum Ca2+-ATPase 2 isoform (SERCA2c)

    PubMed Central

    Dally, Saoussen; Bredoux, Raymonde; Corvazier, Elisabeth; Andersen, Jens P.; Clausen, Johannes D.; Dode, Leonard; Fanchaouy, Mohammed; Gelebart, Pascal; Monceau, Virginie; Del Monte, Frederica; Gwathmey, Judith K.; Hajjar, Roger; Chaabane, Chiraz; Bobe, Régis; Raies, Aly; Enouf, Jocelyne

    2006-01-01

    We recently documented the expression of a novel human mRNA variant encoding a yet uncharacterized SERCA [SR (sarcoplasmic reticulum)/ER (endoplasmic reticulum) Ca2+-ATPase] protein, SERCA2c [Gélébart, Martin, Enouf and Papp (2003) Biochem. Biophys. Res. Commun. 303, 676–684]. In the present study, we have analysed the expression and functional characteristics of SERCA2c relative to SERCA2a and SERCA2b isoforms upon their stable heterologous expression in HEK-293 cells (human embryonic kidney 293 cells). All SERCA2 proteins induced an increased Ca2+ content in the ER of intact transfected cells. In microsomes prepared from transfected cells, SERCA2c showed a lower apparent affinity for cytosolic Ca2+ than SERCA2a and a catalytic turnover rate similar to SERCA2b. We further demonstrated the expression of the endogenous SERCA2c protein in protein lysates isolated from heart left ventricles using a newly generated SERCA2c-specific antibody. Relative to the known uniform distribution of SERCA2a and SERCA2b in cardiomyocytes of the left ventricle tissue, SERCA2c was only detected in a confined area of cardiomyocytes, in close proximity to the sarcolemma. This finding led us to explore the expression of the presently known cardiac Ca2+-ATPase isoforms in heart failure. Comparative expression of SERCAs and PMCAs (plasma-membrane Ca2+-ATPases) was performed in four nonfailing hearts and five failing hearts displaying mixed cardiomyopathy and idiopathic dilated cardiomyopathies. Relative to normal subjects, cardiomyopathic patients express more PMCAs than SERCA2 proteins. Interestingly, SERCA2c expression was significantly increased (166±26%) in one patient. Taken together, these results demonstrate the expression of the novel SERCA2c isoform in the heart and may point to a still unrecognized role of PMCAs in cardiomyopathies. PMID:16402920

  7. Structure, functional regulation and signaling properties of Rap2B

    PubMed Central

    QU, DEBAO; HUANG, HUI; DI, JIEHUI; GAO, KEYU; LU, ZHENG; ZHENG, JUNNIAN

    2016-01-01

    The Ras family small guanosine 5′-triphosphate (GTP)-binding protein Rap2B is is a member of the Ras oncogene family and a novel target of p53 that regulates the p53-mediated pro-survival function of cells. The Rap2B protein shares ~90% homology with Rap2A, and its sequence is 70% identical to other members of the Rap family such as RaplA and RaplB. As a result, Rap2B has been theorized to have similar signaling effectors to the GTPase-binding protein Rap, which mediates various biological functions, including the regulation of sterile 20/mitogen-activated proteins. Since its identification in the early 1990s, Rap2B has elicited a considerable interest. Numerous studies indicate that Rap2B exerts specific biological functions, including binding and stimulating phospholipase C-ε and interferon-γ. In addition, downregulation of Rap2B affects the growth of melanoma cells. The present review summarizes the possible effectors and biological functions of Rap2B. Increasing evidence clearly supports the association between Rap2B function and tumor development. Therefore, it is conceivable that anticancer drugs targeting Rap2B may be generated as novel therapies against cancer. PMID:27073477

  8. Diabetes susceptibility in Mayas: Evidence for the involvement of polymorphisms in HHEX, HNF4α, KCNJ11, PPARγ, CDKN2A/2B, SLC30A8, CDC123/CAMK1D, TCF7L2, ABCA1 and SLC16A11 genes.

    PubMed

    Lara-Riegos, J C; Ortiz-López, M G; Peña-Espinoza, B I; Montúfar-Robles, I; Peña-Rico, M A; Sánchez-Pozos, K; Granados-Silvestre, M A; Menjivar, M

    2015-07-01

    Association of type 2 diabetes (T2D) with common variants in HHEX, HNF4α, KCNJ11, PPARγ, CDKN2A/2B, SLC30A8, CDC123/CAMK1D, TCF7L2, ABCA1 and SLC16A11 genes have been reported, mainly in populations of European and Asian ancestry and to a lesser extent in Latin Americans. Thus, we aimed to investigate the contribution of rs1111875 (HHEX), rs1800961 (HNF4α), rs5219 (KCNJ11), rs1801282 (PPARγ), rs10811661 (CDKN2A/2B), rs13266634 (SLC30A8), rs12779790 (CDC123/CAMK1D), rs7903146 (TCF7L2), rs9282541 (ABCA1) and rs13342692 (SLC16A11) polymorphisms in the genetic background of Maya population to associate their susceptibility to develop T2D. This is one of the first studies designed specifically to investigate the inherited component of T2D in the indigenous population of Mexico. SNPs were genotyped by allelic discrimination method in 575 unrelated Maya individuals. Two SNPs rs10811661 and rs928254 were significantly associated with T2D after adjusting for BMI; rs10811661 in a recessive and rs9282541 in a dominant model. Additionally, we found phenotypical alterations associated with genetic variants: HDL to rs9282541 and insulin to rs13342692. In conclusion, these findings support an association of genetic polymorphisms to develop T2D in Maya population. PMID:25839936

  9. Diabetes susceptibility in Mayas: Evidence for the involvement of polymorphisms in HHEX, HNF4α, KCNJ11, PPARγ, CDKN2A/2B, SLC30A8, CDC123/CAMK1D, TCF7L2, ABCA1 and SLC16A11 genes.

    PubMed

    Lara-Riegos, J C; Ortiz-López, M G; Peña-Espinoza, B I; Montúfar-Robles, I; Peña-Rico, M A; Sánchez-Pozos, K; Granados-Silvestre, M A; Menjivar, M

    2015-07-01

    Association of type 2 diabetes (T2D) with common variants in HHEX, HNF4α, KCNJ11, PPARγ, CDKN2A/2B, SLC30A8, CDC123/CAMK1D, TCF7L2, ABCA1 and SLC16A11 genes have been reported, mainly in populations of European and Asian ancestry and to a lesser extent in Latin Americans. Thus, we aimed to investigate the contribution of rs1111875 (HHEX), rs1800961 (HNF4α), rs5219 (KCNJ11), rs1801282 (PPARγ), rs10811661 (CDKN2A/2B), rs13266634 (SLC30A8), rs12779790 (CDC123/CAMK1D), rs7903146 (TCF7L2), rs9282541 (ABCA1) and rs13342692 (SLC16A11) polymorphisms in the genetic background of Maya population to associate their susceptibility to develop T2D. This is one of the first studies designed specifically to investigate the inherited component of T2D in the indigenous population of Mexico. SNPs were genotyped by allelic discrimination method in 575 unrelated Maya individuals. Two SNPs rs10811661 and rs928254 were significantly associated with T2D after adjusting for BMI; rs10811661 in a recessive and rs9282541 in a dominant model. Additionally, we found phenotypical alterations associated with genetic variants: HDL to rs9282541 and insulin to rs13342692. In conclusion, these findings support an association of genetic polymorphisms to develop T2D in Maya population.

  10. Partial VP2 sequencing of canine parvovirus (CPV) strains circulating in the state of Rio de Janeiro, Brazil: detection of the new variant CPV-2c

    PubMed Central

    Castro, T.X.; Costa, E.M; Leite, J.P.G.; Labarthe, N.V.; Cubel Garcia, R.C.N.

    2010-01-01

    Canine parvovirus (CPV) is the most important enteric virus for dogs and it seems to be undergoing continuous evolution, generating new genetic and antigenic variants throughout the world. The aim of this study was to analyze the distribution of CPV variants from 1995 to 2009 and to investigate the circulation of the new variant CPV-2c in Rio de Janeiro, Brazil. In addition, the clinical features of CPV infection were also reported. After CPV laboratorial confirmation by HA/HI and PCR, thirty-two fecal samples were analyzed by sequencing a 583-bp fragment of the VP2 gene. One sample, collected in 2008 was typed as the new type CPV-2c. All samples from 1995 to 2003 were identified as “new CPV-2a”. From 2004 to 2006, both “new CPV-2a” and CPV-2b were observed. From 2006 to 2009, most of the samples were characterized as CPV-2b. The classical signs of CPV enteritis were observed in 16/18 CPV-2a and 5/13 CPV-2b infected puppies. These results show that continuous epidemiological surveillance of CPV strain distribution is essential for studying the patterns of CPV-2a and 2b spread and for determining whether the new variant CPV-2c has become permanently established in Brazilian canine population. PMID:24031592

  11. What Happened with Spectrometer Magnet 2B

    SciTech Connect

    Green, Michael A

    2010-05-27

    The spectrometer solenoid is supposed to be the first magnets installed in MICE [1]-[4]. This report described what happened during the test of the MICE spectrometer solenoid 2B. First, the report describes the temperatures in the magnet, the cooler top plate and the shield during the run where the magnet quenched at 258 A. During this quench, a lead between the bottom of the HTS leads and the diode bank burned out causing the magnet to quench. Second, three methods for measuring the net heat flow into the cold mass are described. Third, there is a discussion of possible resistive heating in the HTS leads between liquid helium temperature and the copper plate, which is at about 50 K. Fourth, there is a discussion of the measured first stage heat loads in the magnet, when there is no current in the magnet. The first stage heat load calculations are based on knowing the first stage temperatures of the three two-stage pulse tube coolers and the single stage GM cooler. Fifth, the estimated heat load to the first stage when the magnet has current in it is discussed. Sixth, there is a comparison of the stage 1 heat loads in magnet 1A [5], magnet 2A [6], and magnet 2B [7]. Finally there is a discussion of recommended changes for improving the spectrometer solenoids so that the coolers can keep them cold.

  12. First detection of canine parvovirus type 2b from diarrheic dogs in Himachal Pradesh

    PubMed Central

    Sharma, Shalini; Dhar, Prasenjit; Thakur, Aneesh; Sharma, Vivek; Sharma, Mandeep

    2016-01-01

    Aim: The present study was conducted to detect the presence of canine parvovirus (CPV) among diarrheic dogs in Himachal Pradesh and to identify the most prevalent antigenic variant of CPV based on molecular typing and sequence analysis of VP2 gene. Materials and Methods: A total of 102 fecal samples were collected from clinical cases of diarrhea or hemorrhagic gastroenteritis from CPV vaccinated or non-vaccinated dogs. Samples were tested using CPV-specific polymerase chain reaction (PCR) targeting VP2 gene, multiplex PCR for detection of CPV-2a and CPV-2b antigenic variants, and a PCR for the detection of CPV-2c. CPV-2b isolate was cultured on Madin-Darby canine kidney (MDCK) cell lines and sequenced using VP2 structural protein gene. Multiple alignment and phylogenetic analysis was done using ClustalW and MEGA6 and inferred using the Neighbor-Joining method. Results: No sample was found positive for the original CPV strain usually present in the vaccine. However, about 50% (52 out of 102) of the samples were found to be positive with CPV-2ab PCR assay that detects newer variants of CPV circulating in the field. In addition, multiplex PCR assay that identifies both CPV-2ab and CPV-2b revealed that CPV-2b was the major antigenic variant present in the affected dogs. A PCR positive isolate of CPV-2b was adapted to grow in MDCK cells and produced characteristic cytopathic effect after 5th passage. Multiple sequence alignment of VP2 structural gene of CPV-2b isolate (Accession number HG004610) used in the study was found to be similar to other sequenced isolates in NCBI sequence database and showed 98-99% homology. Conclusion: This study reports the first detection of CPV-2b in dogs with hemorrhagic gastroenteritis in Himachal Pradesh and absence of other antigenic types of CPV. Further, CPV-specific PCR assay can be used for rapid confirmation of circulating virus strains under field conditions. PMID:27733797

  13. Thapsigargin activates univalent- and bivalent-cation entry in human neutrophils by a SK&F I3 96365- and Gd3+-sensitive pathway and is a partial secretagogue: involvement of pertussis-toxin-sensitive G-proteins and protein phosphatases 1/2A and 2B in the signal-transduction pathway.

    PubMed Central

    Wenzel-Seifert, K; Krautwurst, D; Musgrave, I; Seifert, R

    1996-01-01

    The Ca2+-ATPase inhibitor thapsigargin (TG) activates bivalent-cation early in human neutrophils via depletion of intracellular Ca2+ stores bu little is known about the underlying mechanism and the functional role of TG-induced cation entry. We studied the effects of TG on univalent- and bivalent cation entry, lysozyme release and superoxide-anion (O2-) formation in human neutrophils. TG, like the chemotactic peptide, N-formyl-L-methionyl-L-leucyl-L-phenylalanine (fMLP), stimulated entry of Ca2+, Mn2+, Ba2+, Sr2+ and Na+ in a 1-¿beta-[3-(4-methoxyphenyl)propoxy]-4-methoxyphenethyl¿-1H-imidazole hydrochloride (SK&F 96365)- and Gd3+-sensitive manner. The inhibitors of protein phosphates 1/2A, calyculin A and okadaic acid, diminished TG-induced cation influxes, whereas the inhibitors of protein phosphatase 2B, cyclosporin A and FK-506, were potentiators. Pertussis toxin (PTX) partially inhibited the effects of TG on Ca2+ and Mn2+ entry. TG and fMLP activated inward currents with a linear current-voltage relationship and a reversal potential at about 0 mV. TG activated lysozyme release and potentiated fMLP-induced O2- formation. TG-induced lysozyme release was inhibited by SK&F 96365, PTX and the removal of extracellular Ca2+ or Na+. Our data show that TG activates a non-selective and SK&F 96365- and Gd3+-sensitive cation entry pathway and is a partial secretagogue. TG-stimulated cation entry involves PTX-sensitive G-proteins and protein phosphatases, with protein phosphatases 1/2A and 2B playing opposite roles. PMID:8670085

  14. Expression of zebrafish nos2b surrounds oral cavity.

    PubMed

    Poon, Kar-Lai; Richardson, Michael; Korzh, Vladimir

    2008-06-01

    Inducible nitric oxide synthase (NOS2) catalyzes the production of nitric oxide (NO), and is one of the factors establishing innate immunity. In zebrafish, Nos2 is represented by nos2a and nos2b. Here, we report the cloning and expression pattern of the zebrafish nos2b gene, which does not seem to participate in induced immune response. nos2b was mapped to zebrafish linkage group 15. The spatial and temporal expression pattern of nos2b in embryonic zebrafish was analyzed by whole-mount in situ hybridization. nos2b is expressed constitutively in two primordia located along the ventral midline. The first group of cells contributes to the neurohypophysis. Initially at the level of the ventral hindbrain, the second group of cells migrates closely with the thyroid primordium to its final position at the basihyal by 3 dpf. Thus, the analysis of expression pattern of nos2b reveals complex morphogenetic movements resulting in its expression surrounding the oral cavity.

  15. The CYP2C19 Intron 2 Branch Point SNP is the Ancestral Polymorphism Contributing to the Poor Metabolizer Phenotype in Livers with CYP2C19*35 and CYP2C19*2 Alleles

    PubMed Central

    Chaudhry, Amarjit S.; Prasad, Bhagwat; Shirasaka, Yoshiyuki; Fohner, Alison; Finkelstein, David; Fan, Yiping; Wang, Shuoguo; Wu, Gang; Aklillu, Eleni; Sim, Sarah C.; Thummel, Kenneth E.

    2015-01-01

    CYP2C19 rs12769205 alters an intron 2 branch point adenine leading to an alternative mRNA in human liver with complete inclusion of intron 2 (exon 2B). rs12769205 changes the mRNA reading frame, introduces 87 amino acids, and leads to a premature stop codon. The 1000 Genomes project (http://browser.1000genomes.org/index.html) indicated rs12769205 is in linkage disequilibrium with rs4244285 on CYP2C19*2, but found alone on CYP2C19*35 in Blacks. Minigenes containing rs12769205 transfected into HepG2 cells demonstrated this single nucleotide polymorphism (SNP) alone leads to exon 2B and decreases CYP2C19 canonical mRNA. A residual amount of CYP2C19 protein was detectable by quantitative proteomics with tandem mass spectrometry in CYP2C19*2/*2 and *1/*35 liver microsomes with an exon 2 probe. However, an exon 4 probe, downstream from rs12769205, but upstream of rs4244285, failed to detect CYP2C19 protein in livers homozygous for rs12769205, demonstrating rs12769205 alone can lead to complete loss of CYP2C19 protein. CYP2C19 genotypes and mephenytoin phenotype were compared in 104 Ethiopians. Poor metabolism of mephenytoin was seen in persons homozygous for both rs12769205 and rs4244285 (CYP2C19*2/*2), but with little effect on mephenytoin disposition of CYP2C19*1/*2, CYP2C19*1/*3, or CYP2C19*1/*35 heterozygous alleles. Extended haplotype homozygosity tests of the HapMap Yorubans (YRI) showed both haplotypes carrying rs12769205 (CYP2C19*35 and CYP2C19*2) are under significant natural selection, with CYP2C19*35 having a higher relative extended haplotype homozygosity score. The phylogenetic tree of the YRI CYP2C19 haplotypes revealed rs12769205 arose first on CYP2C19*35 and that rs4244285 was added later, creating CYP2C19*2. In conclusion, rs12769205 is the ancestral polymorphism leading to aberrant splicing of CYP2C19*35 and CYP2C19*2 alleles in liver. PMID:26021325

  16. Crystal structure of eukaryotic translation initiation factor 2B.

    PubMed

    Kashiwagi, Kazuhiro; Takahashi, Mari; Nishimoto, Madoka; Hiyama, Takuya B; Higo, Toshiaki; Umehara, Takashi; Sakamoto, Kensaku; Ito, Takuhiro; Yokoyama, Shigeyuki

    2016-03-01

    Eukaryotic cells restrict protein synthesis under various stress conditions, by inhibiting the eukaryotic translation initiation factor 2B (eIF2B). eIF2B is the guanine nucleotide exchange factor for eIF2, a heterotrimeric G protein consisting of α-, β- and γ-subunits. eIF2B exchanges GDP for GTP on the γ-subunit of eIF2 (eIF2γ), and is inhibited by stress-induced phosphorylation of eIF2α. eIF2B is a heterodecameric complex of two copies each of the α-, β-, γ-, δ- and ε-subunits; its α-, β- and δ-subunits constitute the regulatory subcomplex, while the γ- and ε-subunits form the catalytic subcomplex. The three-dimensional structure of the entire eIF2B complex has not been determined. Here we present the crystal structure of Schizosaccharomyces pombe eIF2B with an unprecedented subunit arrangement, in which the α2β2δ2 hexameric regulatory subcomplex binds two γε dimeric catalytic subcomplexes on its opposite sides. A structure-based in vitro analysis by a surface-scanning site-directed photo-cross-linking method identified the eIF2α-binding and eIF2γ-binding interfaces, located far apart on the regulatory and catalytic subcomplexes, respectively. The eIF2γ-binding interface is located close to the conserved 'NF motif', which is important for nucleotide exchange. A structural model was constructed for the complex of eIF2B with phosphorylated eIF2α, which binds to eIF2B more strongly than the unphosphorylated form. These results indicate that the eIF2α phosphorylation generates the 'nonproductive' eIF2-eIF2B complex, which prevents nucleotide exchange on eIF2γ, and thus provide a structural framework for the eIF2B-mediated mechanism of stress-induced translational control.

  17. Peginterferon Alfa-2b (PEG-Intron)

    MedlinePlus

    ... powder at room temperature and away from excess heat and moisture (not in the bathroom).It is best to inject peginterferon alfa-2b solution in vials or injection pens immediately after mixing. If necessary, vials or injection pens containing prepared peginterferon alfa-2b solution may be stored ...

  18. Isolation and characterization of canine parvovirus type 2C (CPV-2C) from symptomatic puppies

    PubMed Central

    Puentes, R; Eliopulos, N; Pérez, R; Franco, G; Sosa, K; Bianchi, P; Furtado, A; Hübner, S.O.; Esteves, P.A.

    2012-01-01

    Canine parvovirus type 2 (CPV-2) is a leading cause of diarrhea in puppies in several parts of the world. In this study CPV-2 was detected and recovered from puppies showing clinical disease from Montevideo, Uruguay. Samples were processed and used to infect CRFK and MDCK cells in order to isolate the virus. Out of twelve, two samples were positive for CPV-2. A genomic region of 583 bp was amplified and the molecular characterization was performed by sequencing, phylogenetic analysis and Restriction Fragment Length Polymorphism (RFLP). Two isolated viruses (UY1 and UY2) were CPV-2c-like viruses. The comparison between the cytophatic effect (CPE) of CPV-2 (vaccinal virus) and CPV-2c (isolated virus) on primary canine cells cultures and on CRFK line cells, demonstrated that CPV-2c is less citopathogenic in CRFK than in primary cultures. Our study represents the first report on isolation and characterization of canine parvovirus type 2c (CPV-2c) in cell cultures from South American dogs. PMID:24031919

  19. Isolation and characterization of canine parvovirus type 2C (CPV-2C) from symptomatic puppies.

    PubMed

    Puentes, R; Eliopulos, N; Pérez, R; Franco, G; Sosa, K; Bianchi, P; Furtado, A; Hübner, S O; Esteves, P A

    2012-07-01

    Canine parvovirus type 2 (CPV-2) is a leading cause of diarrhea in puppies in several parts of the world. In this study CPV-2 was detected and recovered from puppies showing clinical disease from Montevideo, Uruguay. Samples were processed and used to infect CRFK and MDCK cells in order to isolate the virus. Out of twelve, two samples were positive for CPV-2. A genomic region of 583 bp was amplified and the molecular characterization was performed by sequencing, phylogenetic analysis and Restriction Fragment Length Polymorphism (RFLP). Two isolated viruses (UY1 and UY2) were CPV-2c-like viruses. The comparison between the cytophatic effect (CPE) of CPV-2 (vaccinal virus) and CPV-2c (isolated virus) on primary canine cells cultures and on CRFK line cells, demonstrated that CPV-2c is less citopathogenic in CRFK than in primary cultures. Our study represents the first report on isolation and characterization of canine parvovirus type 2c (CPV-2c) in cell cultures from South American dogs.

  20. Isolation and characterization of canine parvovirus type 2C (CPV-2C) from symptomatic puppies.

    PubMed

    Puentes, R; Eliopulos, N; Pérez, R; Franco, G; Sosa, K; Bianchi, P; Furtado, A; Hübner, S O; Esteves, P A

    2012-07-01

    Canine parvovirus type 2 (CPV-2) is a leading cause of diarrhea in puppies in several parts of the world. In this study CPV-2 was detected and recovered from puppies showing clinical disease from Montevideo, Uruguay. Samples were processed and used to infect CRFK and MDCK cells in order to isolate the virus. Out of twelve, two samples were positive for CPV-2. A genomic region of 583 bp was amplified and the molecular characterization was performed by sequencing, phylogenetic analysis and Restriction Fragment Length Polymorphism (RFLP). Two isolated viruses (UY1 and UY2) were CPV-2c-like viruses. The comparison between the cytophatic effect (CPE) of CPV-2 (vaccinal virus) and CPV-2c (isolated virus) on primary canine cells cultures and on CRFK line cells, demonstrated that CPV-2c is less citopathogenic in CRFK than in primary cultures. Our study represents the first report on isolation and characterization of canine parvovirus type 2c (CPV-2c) in cell cultures from South American dogs. PMID:24031919

  1. Spectroscopic and structural study of Y 2C 2 carbide encapsulating endohedral metallofullerene: (Y 2C 2)@C 82

    NASA Astrophysics Data System (ADS)

    Inoue, Takashi; Tomiyama, Tetsuo; Sugai, Toshiki; Shinohara, Hisanori

    2003-12-01

    The first di-yttrium carbide endohedral metallofullerene has been produced and spectroscopically and structurally characterized. 13C NMR structural analyses reveal that di-yttrium endohedral metallofullerene having a molecular formula of Y 2C 84 has been found to possess an endohedral yttrium carbide structure, (Y 2C 2)@C 82, in which a Y 2C 2 species is encaged by a C 82-C 3v(8) fullerene. The encaged Y 2C 2 species should rapidly rotate in order to maintain the entire (Y 2C 2)@C 82 molecular symmetry unchanged at room temperature.

  2. Molecular characterization of canine parvovirus strains in Argentina: Detection of the pathogenic variant CPV2c in vaccinated dogs.

    PubMed

    Calderon, Marina Gallo; Mattion, Nora; Bucafusco, Danilo; Fogel, Fernando; Remorini, Patricia; La Torre, Jose

    2009-08-01

    PCR amplification with sequence-specific primers was used to detect canine parvovirus (CPV) DNA in 38 rectal swabs from Argentine domestic dogs with symptoms compatible with parvovirus disease. Twenty-seven out of 38 samples analyzed were CPV positive. The classical CPV2 strain was not detected in any of the samples, but nine samples were identified as CPV2a variant and 18 samples as CPV2b variant. Further sequence analysis revealed a mutation at amino acid 426 of the VP2 gene (Asp426Glu), characteristic of the CPV2c variant, in 14 out of 18 of the samples identified initially by PCR as CPV2b. The appearance of CPV2c variant in Argentina might be dated at least to the year 2003. Three different pathogenic CPV variants circulating currently in the Argentine domestic dog population were identified, with CPV2c being the only variant affecting vaccinated and unvaccinated dogs during the year 2008. PMID:19490967

  3. Human Serotonin 5-HT2C G Protein-Coupled Receptor Homology Model from the β2 Adrenoceptor Structure: Ligand Docking and Mutagenesis Studies

    PubMed Central

    RDOVA-SINTJAGO, TANIA CÓ; VILLA, NANCY; CANAL, CLINTON; BOOTH, RAYMOND

    2013-01-01

    Activation of the serotonin (5-hydroxytryptamine, 5-HT) 5HT2C G protein-coupled receptor (GPCR) is proposed as novel pharmacotherapy for obesity and neuropsychiatric disorders. In contrast, activation of the 5-HT2A and 5-HT2B GPCRs is associated with untoward hallucinogenic and cardiopulmonary effects, respectively. There is no crystal structure available to guide design of 5-HT2C receptor-specific ligands. For this reason, a homology model of the 5-HT2C receptor was built based on the crystal structure of the human β2 adrenoceptor GPCR to delineate molecular determinants of ligand–receptor interactions for drug design purposes. Computational and experimental studies were carried out to validate the model. Binding of N(CH3)2-PAT [(1R, 3S)-(−)-trans-1-phenyl-3-N,N-dimethylamino-1,2,3,4-tetrahydronaphthalene], a novel 5-HT2C agonist/5-HT2A/2B inverse agonist, and its secondary [NH(CH3)-PAT] and primary (NH2-PAT) amine analogs were studied at the 5-HT2C wild type (WT) and D3.32A, S3.36A, and Y7.43A 5-HT2C point-mutated receptors. Reference ligands included the tertiary amines lisuride and mesulergine and the primary amine 5-HT. Modeling results indicated that 5-HT2C residues D3.32, S3.36, and Y7.43 play a role in ligand binding. Experimental ligand binding results with WT and point-mutated receptors confirmed the impact of D3.32, S3.36, and Y7.43 on ligand affinity. PMID:24244046

  4. Investigation of Class 2b Trucks

    SciTech Connect

    Davis, S.C.

    2002-04-03

    The popularity of trucks in the class 2 category--that is, those with a 6,000 to 10,000 pounds (lbs) gross vehicle weight rating (GVWR)--has increased since the late 1970s/early 1980s. The purpose of this research is to identify and examine vehicles in the upper portion of the class 2 weight range (designated as vehicle class 2b) and to assess their impact. Vehicles in class 2b (8,500-10,000 lbs GVWR) include pickup trucks, sport utility vehicles (SUVs), and large vans (i.e., not minivans). Oak Ridge National Laboratory researched each individual truck model to determine which models were class 2b trucks and arrived at four methodologies to derive sales volumes. Two methods--one for calendar year and one for model year sales--were recommended for producing believable and reliable results. The study indicates that 521,000 class 2b trucks were sold in calendar year 1999--6.4% of sales of all trucks under 10,000 lbs. Eighty-two percent of class 2b trucks sold in 1999 were pickups; one third of class 2b trucks sold in 1999 were diesel. There were 5.8 million class 2b trucks on the road in 2000, which amounts to 7.8% of all trucks under 10,000 lbs. Twenty-four percent of the class 2b truck population is diesel. Estimates show that class 2b trucks account for 8% of annual miles traveled by trucks under 10,000 lbs and 9% of fuel use. Data on class 2b trucks are scarce. As the Tier 2 standards, which apply to passenger vehicles in the 8,500-10,000 lb GVWR category, become effective, additional data on class 2b trucks may become available--not only emissions data, but data in all areas. At the moment, distinguishing class 2b trucks from class 2 trucks in general is a substantial task requiring data on an individual model level.

  5. Biotransformation of BDE-47 to Potentially Toxic Metabolites Is Predominantly Mediated by Human CYP2B6

    PubMed Central

    Feo, Maria Luisa; Gross, Michael S.; McGarrigle, Barbara P.; Eljarrat, Ethel; Barceló, Damià; Olson, James R.

    2012-01-01

    Background: Previous studies have indicated that cytochrome P450s (CYPs) are involved in the metabolism of polybrominated diphenyl ether (PBDE) flame retardants in humans, resulting in the formation of hydroxylated PBDEs (OH-PBDEs) that are potentially more toxic than the parent PBDEs. However, the specific enzymes responsible for the formation of OH-PBDEs are unknown. Objectives: The purposes of this study were to characterize the in vitro metabolism of 2,2´,4,4´-tetrabromodiphenyl ether (BDE-47) by human liver microsomes (HLM) and recombinant human CYPs, and to identify the CYP(s) that are active in the oxidative metabolism of BDE-47. Methods: Recombinant human CYPs (CYP1A1, 1A2, 1B1, 2A6, 2B6, 2C8, 2C9, 2C19, 2D6, 2E1, and 3A4) were incubated with BDE-47 (20 µM), and the metabolites were measured and characterized using gas chromatography with tandem mass spectrometry (GC-MS/MS). For kinetic studies, CYP2B6 and pooled human liver microsomes (HLMs) were incubated with BDE-47 (0–60 µM). Results: CYP2B6 was the predominant CYP capable of forming six OH-BDEs, including 3-OH-BDE-47, 5-OH-BDE-47, 6-OH-BDE-47, 4-OH-BDE-42, 4´-OH-BDE-49, and a metabolite tentatively identified as 2´-OH-BDE-66. On the basis of full-scan GC-MS analysis, we hypothesized the formation of two other metabolites: di-OH-tetra-BDE and di-OH-tetrabrominated dioxin. In kinetic studies of BDE-47 metabolism by CYP2B6 and pooled HLMs, we found Km values ranging from 3.8 to 6.4 µM and 7.0 to 11.4 µM, respectively, indicating the high affinity toward the formation of OH-BDEs. Conclusion: Our findings support a predominant role of CYP2B6 in the metabolism of BDE-47 to potentially toxic metabolites, including a hypothesized di-OH-tetrabrominated dioxin metabolite. These results will assist future epidemiological studies investigating the potential of PBDEs and their metabolites to produce neurobehavioral/neurodevelopmental disorders. PMID:23249762

  6. Peginterferon Alfa-2b Injection (Sylatron)

    MedlinePlus

    ... is also available as a different product (PEG-Intron) that is used to treat chronic hepatitis C ( ... to remove it. If you are using Peg-Intron, read the monograph entitled Peginterferon alfa-2b (PEG- ...

  7. Aromatic interactions impact ligand binding and function at serotonin 5-HT2C G protein-coupled receptors: receptor homology modelling, ligand docking, and molecular dynamics results validated by experimental studies

    NASA Astrophysics Data System (ADS)

    Córdova-Sintjago, Tania; Villa, Nancy; Fang, Lijuan; Booth, Raymond G.

    2014-02-01

    The serotonin (5-hydroxytryptamine, 5-HT) 5-HT2 G protein-coupled receptor (GPCR) family consists of types 2A, 2B, and 2C that share ∼75% transmembrane (TM) sequence identity. Agonists for 5-HT2C receptors are under development for psychoses; whereas, at 5-HT2A receptors, antipsychotic effects are associated with antagonists - in fact, 5-HT2A agonists can cause hallucinations and 5-HT2B agonists cause cardiotoxicity. It is known that 5-HT2A TM6 residues W6.48, F6.51, and F6.52 impact ligand binding and function; however, ligand interactions with these residues at the 5-HT2C receptor have not been reported. To predict and validate molecular determinants for 5-HT2C-specific activation, results from receptor homology modelling, ligand docking, and molecular dynamics simulation studies were compared with experimental results for ligand binding and function at wild type and W6.48A, F6.51A, and F6.52A point-mutated 5-HT2C receptors.

  8. Membrane Integration of Poliovirus 2B Viroporin▿

    PubMed Central

    Martínez-Gil, Luis; Bañó-Polo, Manuel; Redondo, Natalia; Sánchez-Martínez, Silvia; Nieva, José Luis; Carrasco, Luis; Mingarro, Ismael

    2011-01-01

    Virus infections can result in a variety of cellular injuries, and these often involve the permeabilization of host membranes by viral proteins of the viroporin family. Prototypical viroporin 2B is responsible for the alterations in host cell membrane permeability that take place in enterovirus-infected cells. 2B protein can be localized at the endoplasmic reticulum (ER) and the Golgi complex, inducing membrane remodeling and the blockade of glycoprotein trafficking. These findings suggest that 2B has the potential to integrate into the ER membrane, but specific information regarding its biogenesis and mechanism of membrane insertion is lacking. Here, we report experimental results of in vitro translation-glycosylation compatible with the translocon-mediated insertion of the 2B product into the ER membrane as a double-spanning integral membrane protein with an N-/C-terminal cytoplasmic orientation. A similar topology was found when 2B was synthesized in cultured cells. In addition, the in vitro translation of several truncated versions of the 2B protein suggests that the two hydrophobic regions cooperate to insert into the ER-derived microsomal membranes. PMID:21835803

  9. Scientific core hole Valles caldera No. 2b (VC-2b), New Mexico

    SciTech Connect

    Garner, J.N.; Hulen, J.B.; Lysne, P.; Jacobson, R.; Goff, F.; Nielson, D.L.; Pisto, L.; Criswell, C.W.; Gribble, R.; Utah Univ. Research Inst., Salt Lake City, UT; Sandia National Labs., Albuquerque, NM; Los Alamos National Lab., NM; Utah Univ. Research Inst., Salt Lake City, UT; Tonto Drilling Services, Inc., Salt Lake City, UT; Los Alamo

    1989-01-01

    Research core hole was continuously cored to 1.762 km on the western flank of the caldera's resurgent dome in 1988. Bottom hole temperature is about 295{degree}C within Precambrian (1.5 Ga) quartz monzonite, deep within the liquid-dominated portions of the Sulphur Springs hydrothermal system. VC-2b may be the deepest, hottest, continuously cored hole in North America. Core recovery was 99.2%. The only major drilling problems encountered were when temperatures at the bit exceeded 225{degree}C below depths of about 1000 m. The result of these conditions was loss of viscosity and/or lubricity in the mud, apparently caused by breakdown of the high temperature polymers. Lithologies in caldera-fill indicate the drill site may be proximal to ignimbrite vents and that an intracaldera lake with temperatures approaching boiling formed soon after the caldera itself. Structural correlations between VC-2b and the 528-m-deep companion hole VC-2a indicate the earlier Toledo caldera (1.45 Ma; Otowi Member tuffs) and even older Lower Tuffs caldera experienced no structural resurgence similar to the 1.12 million year old Valles caldera. The hydrothermal system penetrated by these bores, consists of a shallow vapor-rich cap, which has evolved from an earlier 200{degree}C liquid-dominated system, overlying stacked, liquid-dominated zones up to about 300{degree}C. Geochemistry of mud returns collected during drilling suggests chloride-rich geothermal fluids were entering the bore and mixing with the drilling fluids in the fractured lower Paleozoic and Precambrian sections. 23 refs., 5 figs., 1 tab.

  10. A gain-of-function mutation of Fgfr2c demonstrates the roles of this receptor variant in osteogenesis

    PubMed Central

    Eswarakumar, Veraragavan P.; Horowitz, Mark C.; Locklin, Rachel; Morriss-Kay, Gillian M.; Lonai, Peter

    2004-01-01

    The b and c variants of fibroblast growth factor receptor 2 (FGFR2) differ in sequence, binding specificity, and localization. Fgfr2b, expressed in epithelia, is required for limb outgrowth and branching morphogenesis, whereas the mesenchymal Fgfr2c variant is required by the osteocyte lineage for normal skeletogenesis. Gain-of-function mutations in human FGFR2c are associated with craniosynostosis syndromes. To confirm and extend this evidence, we introduced a Cys342Tyr replacement into Fgfr2c to create a gain-of-function mutation equivalent to a mutation in human Crouzon and Pfeiffer syndromes. Fgfr2cC342Y/+ heterozygote mice are viable and fertile with shortened face, protruding eyes, premature fusion of cranial sutures, and enhanced Spp1 expression in the calvaria. Homozygous mutants display multiple joint fusions, cleft palate, and trachea and lung defects, and die shortly after birth. They show enhanced Cbfa1/Runx2 expression without significant change in chondrocyte-specific Ihh, PTHrP, Sox9, Col2a, or Col10a gene expression. Histomorphometric analysis and bone marrow stromal cell culture showed a significant increase of osteoblast progenitors with no change in osteoclastogenic cells. Chondrocyte proliferation was decreased in the skull base at embryonic day 14.5 but not later. These results suggest that long-term aspects of the mutant phenotype, including craniosynostosis, are related to the Fgfr2c regulation of the osteoblast lineage. The effect on early chondrocyte proliferation but not gene expression suggests cooperation of Fgfr2c with Fgfr3 in the formation of the cartilage model for endochondral bone. PMID:15316116

  11. The Demethylase JMJD2C Localizes to H3K4me3-Positive Transcription Start Sites and Is Dispensable for Embryonic Development

    PubMed Central

    Pedersen, Marianne Terndrup; Agger, Karl; Laugesen, Anne; Johansen, Jens V.; Cloos, Paul A. C.; Christensen, Jesper

    2014-01-01

    The histone demethylase JMJD2C, also known as KDM4C/GASC1, has activity against methylated H3K9 and H3K36 and is amplified and/or overexpressed in human cancers. By the generation of Jmjd2c knockout mice, we demonstrate that loss of Jmjd2c is compatible with cellular proliferation, embryonic stem cell (ESC) self-renewal, and embryonic development. Moreover, we report that JMJD2C localizes to H3K4me3-positive transcription start sites in both primary cells and in the human carcinoma KYSE150 cell line containing an amplification of the JMJD2C locus. Binding is dependent on the double Tudor domain of JMJD2C, which recognizes H3K4me3 but not H4K20me2/me3 in vitro, showing a binding specificity different from that of the double Tudor domains of JMJD2A and JMJD2B. Depletion of JMJD2C in KYSE150 cells has a modest effect on H3K9me3 and H3K36me3 levels but impairs proliferation and leads to deregulated expression of a subset of target genes involved in cell cycle progression. Taking these findings together, we show that JMJD2C is targeted to H3K4me3-positive transcription start sites, where it can contribute to transcriptional regulation, and report that the putative oncogene JMJD2C generally is not required for cellular proliferation or embryonic development. PMID:24396064

  12. B2C graphene, nanotubes, and nanoribbons.

    PubMed

    Wu, Xiaojun; Pei, Yong; Zeng, Xiao Cheng

    2009-04-01

    We report a first-principles prediction of a new two-dimensional inorganic material, namely, the B(2)C graphene in which the boron and carbon atoms are packed into a mosaic of hexagons and rhombuses. In the B(2)C graphene, each carbon atom is bonded with four boron atoms, forming a planar-tetracoordinate carbon (ptC) moiety, a notion first conceived by Hoffmann et al. The B(2)C graphene is possibly a metal with a small overlap in the energy of conduction and valence bands. Like the carbon graphene and nanotubes, a B(2)C graphene sheet can be rolled into various forms of B(2)C nanotubes as well. Depending on the roll-up vector, the B(2)C nanotubes may become either a metal or a semiconductor. All B(2)C graphene nanoribbons are predicted to be uniformly metallic, regardless of their width and edge structure.

  13. Comprehensive Evaluation for Substrate Selectivity of Cynomolgus Monkey Cytochrome P450 2C9, a New Efavirenz Oxidase.

    PubMed

    Hosaka, Shinya; Murayama, Norie; Satsukawa, Masahiro; Uehara, Shotaro; Shimizu, Makiko; Iwasaki, Kazuhide; Iwano, Shunsuke; Uno, Yasuhiro; Yamazaki, Hiroshi

    2015-07-01

    Cynomolgus monkeys are widely used as primate models in preclinical studies, because of their evolutionary closeness to humans. In humans, the cytochrome P450 (P450) 2C enzymes are important drug-metabolizing enzymes and highly expressed in livers. The CYP2C enzymes, including CYP2C9, are also expressed abundantly in cynomolgus monkey liver and metabolize some endogenous and exogenous substances like testosterone, S-mephenytoin, and diclofenac. However, comprehensive evaluation regarding substrate specificity of monkey CYP2C9 has not been conducted. In the present study, 89 commercially available drugs were examined to find potential monkey CYP2C9 substrates. Among the compounds screened, 20 drugs were metabolized by monkey CYP2C9 at a relatively high rates. Seventeen of these compounds were substrates or inhibitors of human CYP2C9 or CYP2C19, whereas three drugs were not, indicating that substrate specificity of monkey CYP2C9 resembled those of human CYP2C9 or CYP2C19, with some differences in substrate specificities. Although efavirenz is known as a marker substrate for human CYP2B6, efavirenz was not oxidized by CYP2B6 but by CYP2C9 in monkeys. Liquid chromatography-mass spectrometry analysis revealed that monkey CYP2C9 and human CYP2B6 formed the same mono- and di-oxidized metabolites of efavirenz at 8 and 14 positions. These results suggest that the efavirenz 8-oxidation could be one of the selective markers for cynomolgus monkey CYP2C9 among the major three CYP2C enzymes tested. Therefore, monkey CYP2C9 has the possibility of contributing to limited specific differences in drug oxidative metabolism between cynomolgus monkeys and humans. PMID:25948712

  14. Comprehensive Evaluation for Substrate Selectivity of Cynomolgus Monkey Cytochrome P450 2C9, a New Efavirenz Oxidase.

    PubMed

    Hosaka, Shinya; Murayama, Norie; Satsukawa, Masahiro; Uehara, Shotaro; Shimizu, Makiko; Iwasaki, Kazuhide; Iwano, Shunsuke; Uno, Yasuhiro; Yamazaki, Hiroshi

    2015-07-01

    Cynomolgus monkeys are widely used as primate models in preclinical studies, because of their evolutionary closeness to humans. In humans, the cytochrome P450 (P450) 2C enzymes are important drug-metabolizing enzymes and highly expressed in livers. The CYP2C enzymes, including CYP2C9, are also expressed abundantly in cynomolgus monkey liver and metabolize some endogenous and exogenous substances like testosterone, S-mephenytoin, and diclofenac. However, comprehensive evaluation regarding substrate specificity of monkey CYP2C9 has not been conducted. In the present study, 89 commercially available drugs were examined to find potential monkey CYP2C9 substrates. Among the compounds screened, 20 drugs were metabolized by monkey CYP2C9 at a relatively high rates. Seventeen of these compounds were substrates or inhibitors of human CYP2C9 or CYP2C19, whereas three drugs were not, indicating that substrate specificity of monkey CYP2C9 resembled those of human CYP2C9 or CYP2C19, with some differences in substrate specificities. Although efavirenz is known as a marker substrate for human CYP2B6, efavirenz was not oxidized by CYP2B6 but by CYP2C9 in monkeys. Liquid chromatography-mass spectrometry analysis revealed that monkey CYP2C9 and human CYP2B6 formed the same mono- and di-oxidized metabolites of efavirenz at 8 and 14 positions. These results suggest that the efavirenz 8-oxidation could be one of the selective markers for cynomolgus monkey CYP2C9 among the major three CYP2C enzymes tested. Therefore, monkey CYP2C9 has the possibility of contributing to limited specific differences in drug oxidative metabolism between cynomolgus monkeys and humans.

  15. STM and STS Observation on Titanium-Carbide Metallofullerenes:. TI2C2@C78

    NASA Astrophysics Data System (ADS)

    Fukui, N.; Moribe, H.; Umemoto, H.; Shinohara, H.; Suwa, Y.; Heike, S.; Fujimori, M.; Hashizume, T.

    2009-06-01

    A metallofullerene Ti2C2@C78, in which two titanium atoms and C2 cluster are encapsulated, is studied by scanning tunneling microscopy and spectroscopy. Measurements of Ti2C2@C78 on Cu(111) surface reveal that their cage symmetry is C78-D3h. There is a preferential orientation of Ti2C2@C78 resulting from electrostatic interaction same as other metallofullerene.

  16. Structure-Activity Relationships and Pharmacophore Model of a Non-Competitive Pyrazoline Containing Class of GluN2C/GluN2D Selective Antagonists

    PubMed Central

    Acker, Timothy M.; Khatri, Alpa; Vance, Katie M.; Slabber, Cathryn; Bacsa, John; Snyder, James P.; Traynelis, Stephen F.; Liotta, Dennis C.

    2013-01-01

    Here we describe the synthesis and structure-activity relationship for a class of pyrazoline-containing dihydroquinolone negative allosteric modulators of the NMDA receptor that show strong subunit-selectivity for GluN2C- and GluN2D-containing receptors over GluN2A-and GluN2B-containing receptors. Several members of this class inhibit NMDA receptor responses in the nanomolar range, and are more than 50-fold selective over GluN1/GluN2A and GluN1/GluN2B NMDA receptors, as well as AMPA, kainate, GABA, glycine, nicotinic, serotonin, and purinergic receptors. Analysis of the purified enantiomers of one of the more potent and selective compounds shows that the S-enantiomer is both more potent and more selective than the R-enantiomer. The S-enantiomer had an IC50 value of 0.17–0.22 µM at GluN2D- and GluN2C-containing receptors, respectively, and showed over 70-fold selectivity over other NMDA receptor subunits. The subunit-selectivity of this class of compounds should be useful in defining the role of GluN2C- and GluN2D-containing receptors in specific brain circuits in both physiological and patho-physiological conditions. PMID:23909910

  17. Cloning and expression of a rat brain. alpha. sub 2B -adrenergic receptor

    SciTech Connect

    Flordellis, C.S.; Handy, D.E.; Bresnahan, M.R.; Zannis, V.I.; Gavras, H. )

    1991-02-01

    The authors isolated a cDNA clone (RB{alpha}{sub 2B}) and its homologous gene (GR{alpha}{sub 2B}) encoding an {alpha}{sub 2B}-adrenergic receptor subtype by screening a rat brain cDNA and a rat genomic library. Nucleotide sequence analysis showed that both clones code for a protein of 458 amino acids, which is 87% homologous to the human kidney glycosylated adrenergic receptor ({alpha}{sub 2}-C4) and divergent from the rat kidney nonglycosylated {alpha}{sub 2B} subtype (RNG{alpha}{sub 2}). Transient expression of RB{alpha}{sub 2B} in COS-7 cells resulted in high-affinity saturable binding for ({sup 3}H)rauwolscine and a high receptor number in the membranes of transfected COS-7 cells. Pharmacological analysis demonstrated that the expressed receptor bound adrenergic ligands with the following order of potency: rauwolscine {gt} yohimbine {gt} prazosin {gt} oxymetazoline, with a prazosin-to-oxymetazoline K{sub i} ratio of 0.34. This profile is characteristic of the {alpha}{sub 2B}-adrenergic receptor subtype. Blotting analysis of rat brain mRNA gave one major and two minor mRNA species, and hybridization with strand-specific probes showed that both DNA strands of GR{alpha}{sub 2B} may be transcriptionally active. These findings show that rat brain expresses an {alpha}{sub 2B}-adrenergic receptor subtype that is structurally different from the rat kidney nonglycosylated {alpha}{sub 2B} subtype. Thus the rat expresses at least two divergent {alpha}{sub 2B}-adrenergic receptors.

  18. Transcription factor activating protein 2 beta (TFAP2B) mediates noradrenergic neuronal differentiation in neuroblastoma.

    PubMed

    Ikram, Fakhera; Ackermann, Sandra; Kahlert, Yvonne; Volland, Ruth; Roels, Frederik; Engesser, Anne; Hertwig, Falk; Kocak, Hayriye; Hero, Barbara; Dreidax, Daniel; Henrich, Kai-Oliver; Berthold, Frank; Nürnberg, Peter; Westermann, Frank; Fischer, Matthias

    2016-02-01

    Neuroblastoma is an embryonal pediatric tumor that originates from the developing sympathetic nervous system and shows a broad range of clinical behavior, ranging from fatal progression to differentiation into benign ganglioneuroma. In experimental neuroblastoma systems, retinoic acid (RA) effectively induces neuronal differentiation, and RA treatment has been therefore integrated in current therapies. However, the molecular mechanisms underlying differentiation are still poorly understood. We here investigated the role of transcription factor activating protein 2 beta (TFAP2B), a key factor in sympathetic nervous system development, in neuroblastoma pathogenesis and differentiation. Microarray analyses of primary neuroblastomas (n = 649) demonstrated that low TFAP2B expression was significantly associated with unfavorable prognostic markers as well as adverse patient outcome. We also found that low TFAP2B expression was strongly associated with CpG methylation of the TFAP2B locus in primary neuroblastomas (n = 105) and demethylation with 5-aza-2'-deoxycytidine resulted in induction of TFAP2B expression in vitro, suggesting that TFAP2B is silenced by genomic methylation. Tetracycline inducible re-expression of TFAP2B in IMR-32 and SH-EP neuroblastoma cells significantly impaired proliferation and cell cycle progression. In IMR-32 cells, TFAP2B induced neuronal differentiation, which was accompanied by up-regulation of the catecholamine biosynthesizing enzyme genes DBH and TH, and down-regulation of MYCN and REST, a master repressor of neuronal genes. By contrast, knockdown of TFAP2B by lentiviral transduction of shRNAs abrogated RA-induced neuronal differentiation of SH-SY5Y and SK-N-BE(2)c neuroblastoma cells almost completely. Taken together, our results suggest that TFAP2B is playing a vital role in retaining RA responsiveness and mediating noradrenergic neuronal differentiation in neuroblastoma. PMID:26598443

  19. Development and validation of a simple LC method for the determination of phenacetin, coumarin, tolbutamide, chlorzoxazone, testosterone and their metabolites as markers of cytochromes 1A2, 2A6, 2C11, 2E1 and 3A2 in rat microsomal medium.

    PubMed

    Zhai, Xuejia; Lu, Yongning

    2013-01-01

    Cytochrome P450 enzymes are responsible for the oxidative metabolism of most pharmaceutical compounds. A "cocktail" approach which employs simultaneous administration of a mixture of substrates of CYP enzymes was often used to assess the metabolic activity of multiple P450 forms in one experiment. Phenacetin, coumarin, tolbutamide, chlorzoxazone and testosterone are commonly used as probe substrates to evaluate cytochrome P450 function. An analytical strategy to simultaneously extract and analyze the five probe substrates and their major metabolites by HPLC-DAD was developed. The incubation was done with all the substrates in one step. The ten analytes were extracted simultaneously by solid-phase extraction (SPE) from rat liver microsomes. A C18 analytical column and mobile phase composed of acetonitrile and 0.02% aqueous phosphoric acid were used for the chromatographic separation with DAD detection. Limits of quantification varied between 0.02378 and 0.2361 microg/mL which contributed to quantify all these drugs and metabolites with UV detection. The method is applicable for the modeling and description of pharmacological interactions on rat cytochromes P450 or can be used for in vitro evaluation of cytochromes 1A2, 2A6, 2C11, 2E1 and 3A2.

  20. Human cytochrome P450-catalyzed conversion of the proestrogenic pesticide methoxychlor into an estrogen. Role of CYP2C19 and CYP1A2 in O-demethylation.

    PubMed

    Stresser, D M; Kupfer, D

    1998-09-01

    1,1,1-Trichloro-2,2-bis(4-methoxyphenyl)ethane (methoxychlor) is a widely used pesticide that is pro-estrogenic. We have elucidated the human cytochrome P450 enzymes responsible for conversion of methoxychlor into its major metabolite, the mono-O-demethylated derivative (mono-OH-M) that is estrogenic. Incubation of methoxychlor with microsomes from insect cells overexpressing either CYP1A2, CYP2C18, or CYP2C19 yielded mono-OH-M with turnover numbers of 14.9, 15.5, and 39.1 nmol/min/nmol of P450, respectively. CYP2B6 and CYP2C9 were much less active. Incubations with purified CYP2C19 and CYP2C18 resulted in formation of mono-OH-M, and also the bis-demethylated metabolite. Co-incubation of liver microsomes with methoxychlor and various P450 isoform-selective inhibitors suggested involvement of several P450s in mono-O-demethylation, including CYP1A2, CYP2A6, CYP2C9, and CYP2C19. A role for CYP2C19, CYP1A2, and CYP2A6 was also indicated by multivariate regression analysis of the mono-O-demethylase activity in a panel of human liver microsomes characterized for isoform-specific catalytic activities (R2 = 0.96). Based on the totality of the evidence, CYP2C19 appears to be the major catalyst of methoxychlor mono-O-demethylation. However, in individuals lacking functional CYP2C19 (e.g. the "poor metabolizer" phenotype), CYP1A2 may play the predominant role. CYP2A6, CYP2C9, and CYP2B6 probably contribute to a lesser extent. Although CYP2C18 is an efficient methoxychlor demethylase, its expression in liver is reportedly low or absent, suggesting a negligible role for this enzyme in methoxychlor metabolism. Lengthy incubations of liver microsomes with methoxychlor produced other secondary and tertiary metabolites. Efficient conversion of methoxychlor to estrogenic mono-OH-M by liver microsomes suggests that methoxychlor has the potential to be estrogenic in humans, as observed in several animal species.

  1. Curtiss SB2C-1 Helldiver

    NASA Technical Reports Server (NTRS)

    1944-01-01

    Curtiss SB2C-1 Helldiver: This Curtiss SB2C-1 Helldiver was flown by the NACA at Langley with an early radio-control system. Flying controls such as a spring tab were also examined with this airframe. Helldivers were also operated by the U. S. Army as A-25 Shrikes.

  2. SB 242084, a selective and brain penetrant 5-HT2C receptor antagonist.

    PubMed

    Kennett, G A; Wood, M D; Bright, F; Trail, B; Riley, G; Holland, V; Avenell, K Y; Stean, T; Upton, N; Bromidge, S; Forbes, I T; Brown, A M; Middlemiss, D N; Blackburn, T P

    1997-01-01

    SB 242084 has a high affinity (pKi 9.0) for the cloned human 5-HT2C receptor and 100- and 158-fold selectivity over the closely related cloned human 5-HT2B and 5-HT2A subtypes respectively. SB 242084 had over 100-fold selectivity over a range of other 5-HT, dopamine and adrenergic receptors. In studies of 5-HT-stimulated phosphatidylinositol hydrolysis using SH-SY5Y cells stably expressing the cloned human 5-HT2C receptor, SB 242084 acted as an antagonist with a pKb of 9.3, which closely resembled its corresponding receptor binding affinity. SB 242084 potently inhibited m-chlorophenylpiperazine (mCPP, 7 mgkg i.p. 20 min pre-test)-induced hypolocomotion in rats, a model of in vivo central 5-HT2C receptor function, with an ID50 of 0.11 mg/kg i.p., and 2.0 mg/kg p.o. SB 242084 (0.1-1 mg/kg i.p.) exhibited an anxiolytic-like profile in the rat social interaction test, increasing time spent in social interaction, but having no effect on locomotion. SB 242084 (0.1-1 mg/kg i.p.) also markedly increased punished responding in a rat Geller-Seifter conflict test of anxiety, but had no consistent effect on unpunished responding. A large acute dose of SB 242084 (30 mg/kg p.o.) had no effect on seizure susceptibility in the rat maximal electroshock seizure threshold test. Also, while SB 242084 (2 and 6 mg/kg p.o. 1 hr pre-test) antagonized the hypophagic response to mCPP, neither acute nor subchronic administration of the drug, for 5 days at 2 or 6 mg/kg p.o. twice daily, affected food intake or weight gain. The results suggest that SB 242084 is the first reported selective potent and brain penetrant 5-HT2C receptor antagonist and has anxiolytic-like activity, but does not possess either proconvulsant or hyperphagic properties which are characteristic of mutant mice lacking the 5-HT2C receptor. PMID:9225286

  3. New imidazo[1,2-b]pyrazoles as anticancer agents: synthesis, biological evaluation and structure activity relationship analysis.

    PubMed

    Grosse, Sandrine; Mathieu, Véronique; Pillard, Christelle; Massip, Stéphane; Marchivie, Mathieu; Jarry, Christian; Bernard, Philippe; Kiss, Robert; Guillaumet, Gérald

    2014-09-12

    Synthesis and functionalization strategies of the imidazo[1,2-b]pyrazole core were developed giving a rapid access to three series of novel imidazo[1,2-b]pyrazole type derivatives: C-2/C-6/C-7 trisubstituted, C-2/C-3/C-6 tri(hetero)arylated and C-2/C-3/C-6/C-7 tetrasubstituted imidazo[1,2-b]pyrazoles. 39 of the synthetized products were evaluated for in vitro anticancer activity using the MTT colorimetric assay against 5 human and 1 murine cancer cell lines. Promising in vitro growth inhibitory activities were exhibited by some of the target compounds. Of the 39 evaluated products, 4 displayed an IC50 ≤ 10 μM in the 6 cell lines analyzed (compounds 4d, 4g, 9a, 11a). A structure activity relationship analysis is also reported in this paper. PMID:25064349

  4. Global variation in CYP2C8–CYP2C9 functional haplotypes

    PubMed Central

    Speed, William C; Kang, Soonmo Peter; Tuck, David P; Harris, Lyndsay N; Kidd, Kenneth K

    2009-01-01

    We have studied the global frequency distributions of 10 single nucleotide polymorphisms (SNPs) across 132 kb of CYP2C8 and CYP2C9 in ∼2500 individuals representing 45 populations. Five of the SNPs were in noncoding sequences; the other five involved the more common missense variants (four in CYP2C8, one in CYP2C9) that change amino acids in the gene products. One haplotype containing two CYP2C8 coding variants and one CYP2C9 coding variant reaches an average frequency of 10% in Europe; a set of haplotypes with a different CYP2C8 coding variant reaches 17% in Africa. In both cases these haplotypes are found in other regions of the world at <1%. This considerable geographic variation in haplotype frequencies impacts the interpretation of CYP2C8/CYP2C9 association studies, and has pharmacogenomic implications for drug interactions. PMID:19381162

  5. Actions of the prototypical 5-HT1A receptor agonist 8-OH-DPAT at human alpha2-adrenoceptors: (+)8-OH-DPAT, but not (-)8-OH-DPAT is an alpha2B subtype preferential agonist.

    PubMed

    Heusler, Peter; Rauly-Lestienne, Isabelle; Tourette, Amélie; Tardif, Stéphanie; Ailhaud, Marie-Christine; Croville, Guillaume; Cussac, Didier

    2010-08-25

    8-OH-DPAT [8-hydroxy-2-(di-n-propylamino)tetralin] is the prototypical agonist at serotonin 5-HT1A receptors; however, activity at other targets contributes to the functional effects of the compound as well. We examined the properties of 8-OH-DPAT and its enantiomers at recombinant human (h)alpha2-adrenoceptor subtypes, using a panel of radioligand binding and functional tests. In competition binding experiments using [3H]-RX821002, about 10-fold selectivity of (+)8-OH-DPAT for the halpha2B subtype (pKi about 7) over halpha2A- and halpha2C-adrenoceptors was observed. In contrast, the S(-) enantiomer of 8-OH-DPAT showed similar weak affinities for the three receptor subtypes (pKis<6). The binding affinity of (+)8-OH-DPAT at the halpha2B- and the halpha2A-adrenoceptor was found sensitive to GTPgammaS, a receptor/G protein-uncoupling agent, indicating agonist properties of the drug. Furthermore, using [35S]GTPgammaS binding determination at CHO-halpha2B or CHO-halpha2A cell membranes and G protein coupled inwardly rectifying potassium (GIRK) current recordings in Xenopus oocytes expressing halpha2B, partial agonist activity of (+)8-OH-DPAT at the respective receptors was confirmed in these two different functional assays. Potency of (+)8-OH-DPAT for stimulation of [35S]GTPgammaS incorporation was lower at the halpha2A- than at the halpha2B-adrenoceptor, consistent with binding affinities. Thus, (+)8-OH-DPAT and, as a consequence, racemic (+/-)8-OH-DPAT are partial agonists at halpha2-adrenoceptors with selectivity for the halpha2B subtype, a property that might contribute to the effects of the compound described in native systems.

  6. Reactions of vanadium dioxide molecules with acetylene: infrared spectra of VO2(η(2)-C2H2)(x) (x = 1, 2) and OV(OH)CCH in solid neon.

    PubMed

    Zhou, Xiaojie; Chen, Mohua; Zhou, Mingfei

    2013-07-01

    Reactions of vanadium dioxide molecules with acetylene have been studied by matrix isolation infrared spectroscopy. Reaction intermediates and products are identified on the basis of isotopic substitutions as well as density functional frequency calculations. Ground state vanadium dioxide molecule reacts with acetylene in forming the side-on-bonded VO2(η(2)-C2H2) and VO2(η(2)-C2H2)2 complexes spontaneously on annealing in solid neon. The VO2(η(2)-C2H2) complex is characterized to have a (2)B2 ground state with C2v symmetry, whereas the VO2(η(2)-C2H2)2 complex has a (2)A ground state with C2 symmetry. The VO2(η(2)-C2H2) and VO2(η(2)-C2H2)2 complexes are photosensitive. The VO2(η(2)-C2H2) complex rearranges to the OV(OH)CCH molecule upon UV-vis light excitation.

  7. Curtiss SB2C-1 Helldiver

    NASA Technical Reports Server (NTRS)

    1943-01-01

    Curtiss SB2C-1 Helldiver: The front canopy came off this Curtiss SB2C-1 Helldiver while it was in flight, injuring pilot Herbert H. Hoover, but he recovered the plane back to the NACA at Langley Field. SB2Cs were license-built by Fairchild as SBFs and by Canadian Car and Foundry as SBWs. Helldivers were also flown by the British and Australians.

  8. Phylogenetic analysis of porcine circovirus type 2 (PCV2) isolates from China with high homology to PCV2c.

    PubMed

    Liu, Xing; Wang, Feng-Xue; Zhu, Hong-Wei; Sun, Na; Wu, Hua

    2016-06-01

    Porcine circovirus type 2 (PCV2) is an important emerging pathogen that has been causatively associated with multifactorial disease syndromes in pigs and other species. It has a worldwide distribution and causes significant economic losses in the swine industry. Its genome is dynamically evolving through recombination and mutation, and the circulating genotypes of PCV2 strains in Asia are PCV2a, PCV2b and PCV2d. In this study, 12 PCV isolates were evaluated and identified by amplification, sequencing, and phylogenetic analysis, and the results revealed a new monophyletic group of PCV in China. More importantly, three of these isolates shared high homology within the ORF1 region with a strain of genotype PCV2c that was detected only in Denmark. Phylogeographic analysis of these isolates suggested that the isolates may have arisen in Denmark and that they were then transported to China. PMID:27016927

  9. Up-regulation of 5-HT2B receptor density and receptor-mediated glycogenolysis in mouse astrocytes by long-term fluoxetine administration.

    PubMed

    Kong, Ebenezer K C; Peng, Liang; Chen, Ye; Yu, Albert C H; Hertz, Leif

    2002-02-01

    The effects were studied of short-term (1 week) versus long-term (2-3 weeks) fluoxetine treatment of primary cultures of mouse astrocytes, differentiated by treatment with dibutyryl cyclic AMP. From previous experiments it is known that acute treatment with fluoxetine stimulates glycogenolysis and increases free cytosolic Ca2+ concentration ([Ca2+]i]) in these cultures, whereas short-term (one week) treatment with 10 microM down-regulates the effects on glycogen and [Ca2+]i, when fluoxetine administration is renewed (or when serotonin is administered). Moreover, antagonist studies have shown that these responses are evoked by activation of a 5-HT2, receptor that is different from the 5-HT2A receptor and therefore at that time tentatively were interpreted as being exerted on 5-HT2C receptors. In the present study the cultures were found by RT-PCR to express mRNA for 5-HT2A and 5-HT2B receptors, but not for the 5-HT2C receptor, identifying the 5-HT2 receptor activated by fluoxetine as the 5-HT2B receptor, the most recently cloned 5-Ht2 receptor and a 5-HT receptor known to be more abundant in human, than in rodent, brain. Both short-term and long-term treatment with fluoxetine increased the specific binding of [3H]mesulergine, a ligand for alL three 5-HT2 receptors. Long-term treatment with fluoxetine caused an agonist-induced up-regulation of the glycogenolytic response to renewed administration of fluoxetine, whereas short-term treatment abolished the fluoxetine-induced hydrolysis of glycogen. Thus, during a treatment period similar to that required for fluoxetine's clinical response to occur, 5-HT2B-mediated effects are initially down-regulated and subsequently up-regulated. PMID:11930908

  10. Noncanonical sortase-mediated assembly of pilus type 2b in group B Streptococcus.

    PubMed

    Lazzarin, Maddalena; Cozzi, Roberta; Malito, Enrico; Martinelli, Manuele; D'Onofrio, Mariapina; Maione, Domenico; Margarit, Immaculada; Rinaudo, C Daniela

    2015-11-01

    Group B Streptococcus (GBS) expresses 3 structurally distinct pilus types (1, 2a, and 2b) identified as important virulence factors and vaccine targets. These pili are heterotrimeric polymers, covalently assembled on the cell wall by sortase (Srt) enzymes. We investigated the pilus-2b biogenesis mechanism by using a multidisciplinary approach integrating genetic, biochemical, and structural studies to dissect the role of the 2 pilus-2b-associated Srts. We show that only 1 sortase (SrtC1-2b) is responsible for pilus protein polymerization, whereas the second one (Srt2-2b) does not act as a pilin polymerase, but similarly to the housekeeping class A Srt (SrtA), it is involved in cell-wall pilus anchoring by targeting the minor ancillary subunit. Based on its function and sequence features, Srt2-2b does not belong to class C Srts (SrtCs), nor is it a canonical member of any other known family of Srts. We also report the crystal structure of SrtC1-2b at 1.9 Å resolution. The overall fold resembles the typical structure of SrtCs except for the N-terminal lid region that appears in an open conformation displaced from the active site. Our findings reveal that GBS pilus type 2b biogenesis differs significantly from the current model of pilus assembly in gram-positive pathogens.

  11. Photoelectron spectra of thulium atoms encapsulated C82 fullerene, Tm2@C82 (III) and Tm2C2@C82 (III)

    NASA Astrophysics Data System (ADS)

    Miyazaki, Takafumi; Tokumoto, Youji; Sumii, Ryohei; Yagi, Hajime; Izumi, Noriko; Shinohara, Hisanori; Hino, Shojun

    2014-03-01

    Ultraviolet photoelectron spectra (UPS) and X-ray photoelectron spectra (XPS) of two thulium atoms and thulium-carbide cluster entrapped fullerenes, Tm2@C82 (III) and Tm2C2@C82 (III), were measured using synchrotron radiation and MgKα X-ray light sources. The UPS spectral onset energy of these endohedral fullerenes is around 0.9 eV, which is smaller than that of 1.2 eV of empty C82. The UPS of Tm2@C82 (III) and Tm2C2@C82 (III) resemble each other. Further, the UPS of Tm2@C82 (III), Y2@C82-C3v and Er2@C82-C3v are almost identical and as well as are Tm2C2@C82 (III), Y2C2@C82-C3v and Er2C2@C82-C3v. The XPS Tm4d5/2 peaks of Tm2@C82 and Tm2C2@C82 appear at higher binding energy region than that of Tm@C82, which suggests the oxidation states of Tm atoms in Tm2@C82 (III) and Tm2C2@C82 are higher than that in Tm@C82.

  12. Nanosegregation in Na2C60

    SciTech Connect

    Klupp, G.; Kamaras, K.; Matus, P.; Kiss, L.F.; Kovats, E.; Pekker, S.; Nemes, N.M.; Quintavalle, D.; Janossy, A.

    2005-09-27

    There is continuous interest in the nature of alkali metal fullerides containing C{sub 60}{sup 4-} and C{sub 60}{sup 2-}, because these compounds are believed to be nonmagnetic Mott-Jahn-Teller insulators. This idea could be verified in the case of A4C60, but Na2C60 is more controversial. By comparing the results of infrared spectroscopy and X-ray diffraction, we found that Na2C60 is segregated into 3-10 nm large regions. The two main phases of the material are insulating C60 and metallic Na3C60. We found by neutron scattering that the diffusion of sodium ions becomes faster on heating. Above 470 K Na2C60 is homogeneous and we show IR spectroscopic evidence of a Jahn-Teller distorted C{sub 60}{sup 2-} anion.

  13. Control of sensory neuron excitability by serotonin involves 5HT2C receptors and Ca(2+)-activated chloride channels.

    PubMed

    Salzer, Isabella; Gantumur, Enkhbileg; Yousuf, Arsalan; Boehm, Stefan

    2016-11-01

    Serotonin (5HT) is a constituent of the so-called "inflammatory soup" that sensitizes nociceptors during inflammation. Nevertheless, receptors and signaling mechanisms that mediate an excitation of dorsal root ganglion (DRG) neurons by 5HT remained controversial. Therefore, capsaicin-sensitive nociceptive neurons dissociated from rat DRGs were used to investigate effects of 5HT on membrane excitability and currents through ligand- as well as voltage-gated ion channels. In 58% of the neurons tested, 5HT increased action potential firing, an effect that was abolished by the 5HT2 receptor antagonist ritanserin, but not by the 5HT3 antagonist tropisetron. Unlike other algogenic mediators, such as PGE2 and bradykinin, 5HT did not affect currents through TTX-resistant Na(+) channels or Kv7 K(+) channels. In all neurons investigated, 5HT potentiated capsaicin-evoked currents through TRPV1 channels, an effect that was attenuated by antagonists at 5HT2A (4 F 4 PP), 5HT2B (SB 204741), as well as 5HT2C (RS 102221) receptors. 5HT triggered slowly arising inward Cl(-) currents in 53% of the neurons. This effect was antagonized by the 5HT2C receptor blocker only, and the current was prevented by an inhibitor of Ca(2+)-activated chloride channels (CaCC). The 5HT-induced increase in action potential firing was also abolished by this CaCC blocker and by the TRPV1 inhibitor capsazepine. Amongst the subtype selective 5HT2 antagonists, only RS 102221 (5HT2C-selectively) counteracted the rise in action potential firing elicited by 5HT. These results show that 5HT excites DRG neurons mainly via 5HT2C receptors which concomitantly mediate a sensitization of TRPV1 channels and an opening of CaCCs.

  14. Synthesis and Electrochemical Properties of Nano-VO2 (B).

    PubMed

    Yang, Yun; Lu, Yong; Wang, Wei; Feng, Chuanqi; Yang, Shuijin

    2016-03-01

    The nano-VO2 (B) has been self-assembly synthesized by hydrothermal method using different templates, which may give them some interesting properties. The as-prepared samples were characterized by X-ray powder diffraction (XRD) and scanning electron microscopy (SEM). The electrochemical properties of the samples were investigated. The results show that the hexadecyltrimethyl ammonium bromide (CTAB) (soft template) was used to obtain the VO2 (B1) nanobelts. The flake graphite (hard template) was taken to get the VO2 (B2) nanosheets. The VO2 (B1) nanobelts have higher initial capacity to compare with VO2 (B2). But the VO2 (B2) nanosheets showed better cycling performance than that of VO2 (B1) nanobelts. The nano VO2 (B2) is a promising anode material for lithium ion battery application. PMID:27455666

  15. 75 FR 34657 - Airworthiness Directives; Bombardier, Inc. Model CL-600-2B19 (Regional Jet Series 100 & 440...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-06-18

    ... and generator housing assembly, have been reported on CL-600-2B19 aircraft. The same part is also installed on CL-600-2C10, -2D15 and -2D24 aircraft. Investigation determined that the crack was in an area... possibly result in damage to the aircraft structure. If deployment was activated by a dual engine...

  16. 7 CFR 301.85-2b - Exempted articles. 1

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 5 2011-01-01 2011-01-01 false Exempted articles. 1 301.85-2b Section 301.85-2b... § 301.85-2b Exempted articles. 1 1 The articles hereby exempted remain subject to applicable restrictions under other quarantines and other provisions of this subpart. (a) The following articles...

  17. 7 CFR 301.85-2b - Exempted articles. 1

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 5 2012-01-01 2012-01-01 false Exempted articles. 1 301.85-2b Section 301.85-2b... § 301.85-2b Exempted articles. 1 1 The articles hereby exempted remain subject to applicable restrictions under other quarantines and other provisions of this subpart. (a) The following articles...

  18. 7 CFR 301.85-2b - Exempted articles. 1

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 5 2010-01-01 2010-01-01 false Exempted articles. 1 301.85-2b Section 301.85-2b... § 301.85-2b Exempted articles. 1 1 The articles hereby exempted remain subject to applicable restrictions under other quarantines and other provisions of this subpart. (a) The following articles...

  19. 7 CFR 301.85-2b - Exempted articles. 1

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 5 2014-01-01 2014-01-01 false Exempted articles. 1 301.85-2b Section 301.85-2b... § 301.85-2b Exempted articles. 1 1 The articles hereby exempted remain subject to applicable restrictions under other quarantines and other provisions of this subpart. (a) The following articles...

  20. 7 CFR 301.85-2b - Exempted articles. 1

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 5 2013-01-01 2013-01-01 false Exempted articles. 1 301.85-2b Section 301.85-2b... § 301.85-2b Exempted articles. 1 1 The articles hereby exempted remain subject to applicable restrictions under other quarantines and other provisions of this subpart. (a) The following articles...

  1. Design, Synthesis, and Evaluation of Tetrasubstituted Pyridines as Potent 5-HT2C Receptor Agonists

    PubMed Central

    2015-01-01

    A series of pyrido[3,4-d]azepines that are potent and selective 5-HT2C receptor agonists is disclosed. Compound 7 (PF-04781340) is identified as a suitable lead owing to good 5-HT2C potency, selectivity over 5-HT2B agonism, and in vitro ADME properties commensurate with an orally available and CNS penetrant profile. The synthesis of a novel bicyclic tetrasubstituted pyridine core template is outlined, including rationale to account for the unexpected formation of aminopyridine 13 resulting from an ammonia cascade cyclization. PMID:25815155

  2. Sc3N and Sc2C2 encapsulated B40: Smarter than its carbon analogue

    NASA Astrophysics Data System (ADS)

    Shah, Esha V.; Roy, Debesh R.

    2016-10-01

    A detailed comparative investigation on the recently synthesised B40 and C40 along with their metal nitride (Sc3N)and carbide (Sc2C2) encapsulated endohedral fullerenes, is performed under density functional theory for the first time. The structures, electronic, thermodynamic and magnetic properties of all the considered compounds are explored in detail. The present study identifies borospherene (B40) and its encapsulated nitride (Sc3N@B40) and carbide (Sc2C2@B40) endohedral borofullerenes as the better candidates for future novel nano-applications compared to their carbon bucky ball analogues.

  3. Hydroxysteroid sulfotransferase 2B1b expression and localization in normal human brain

    PubMed Central

    Salman, Emily D.; Faye-Petersen, Ona; Falany, Charles N.

    2012-01-01

    Steroid sulfonation in the human brain has not been well characterized. The major sulfotransferase (SULT) isoforms that conjugate steroids in humans are SULT1E1, SULT2A1, and SULT2B1b. SULT2B1b catalyzes the sulfonation of 3β-hydroxysteroids, including neurosteroids dehydroepiandrosterone and pregnenolone, as well as cholesterol and several hydroxycholesterols. SULT2B1b mRNA and protein expression were detected in adult and fetal human brain sections, whereas neither mRNA, nor protein expression were identified for SULT1E1 or SULT2A1. Using immunohistochemical analysis, SULT2B1b expression was detected in neurons and oligodendrocytes in adult brain and in epithelial tissues in 28-week-old fetal brain. Sulfonation of cholesterol, oxysterols, and neurosteroids in the brain is apparently catalyzed by SULT2B1b since expression of neither SULT2A1 nor SULT1E1 was detected in human brain sections. SULT2B1b mRNA and protein were also detected in human U373-MG glioblastoma cells. Both mRNA and protein expression of liver X receptor (LXR)-β, but not LXR-α, were detected in U373-MG cells, and LXR-β activation resulted in a decrease in SULT2B1b protein expression. Since hydroxycholesterols are important physiological LXR activators, this suggests a role for regulation of sterol metabolism by LXR and SULT2B1b. Therefore, elucidating key enzymes in the metabolism of cholesterol and neurosteroids could help define the properties of steroid conjugation in the human brain. PMID:24683427

  4. PHOX2B is a suppressor of neuroblastoma metastasis

    PubMed Central

    Naftali, Osnat; Maman, Shelly; Meshel, Tsipi; Sagi-Assif, Orit; Ginat, Ravit; Witz, Isaac P.

    2016-01-01

    Paired like homeobox 2B (PHOX2B) is a minimal residual disease (MRD) marker of neuroblastoma. The presence of MRD, also referred to as micro-metastases, is a powerful marker of poor prognosis in neuroblastoma. Lung metastasis is considered a terminal event in neuroblastoma. Lung micro-metastatic neuroblastoma (MicroNB) cells show high expression levels of PHOX2B and possess a less malignant and metastatic phenotype than lung macro metastatic neuroblastoma (MacroNB) cells, which hardly express PHOX2B. In vitro assays showed that PHOX2B knockdown in MicroNB cells did not affect cell viability; however it decreased the migratory capacity of the MicroNB-shPHOX2B cells. An orthotopic inoculation of MicroNB-shPHOX2B cells into the adrenal gland of nude mice resulted in significantly larger primary tumors and a heavier micro-metastatic load in the lungs and bone-marrow, than when control cells were inoculated. PHOX2B expression was found to be regulated by methylation. The PHOX2B promoter in MacroNB cells is significantly more methylated than in MicroNB cells. Demethylation assays using 5-azacytidine demonstrated that methylation can indeed inhibit PHOX2B transcription in MacroNB cells. These pre-clinical data strongly suggest that PHOX2B functions as a suppressor of neuroblastoma progression. PMID:26840262

  5. 75 FR 79990 - Airworthiness Directives; B-N Group Ltd. Model BN-2, BN-2A, BN-2A-2, BN-2A-3, BN-2A-6, BN-2A-8...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-12-21

    ... Procedures (44 FR 11034, February 26, 1979); and 3. Will not have a significant economic impact, positive or.... Model BN-2, BN-2A, BN- 2A-2, BN-2A-3, BN-2A-6, BN-2A-8, BN-2A-9, BN-2A-20, BN-2A-21, BN-2A-26, BN-2A-27, BN-2B-20, BN-2B-21, BN-2B-26, BN-2B-27, BN-2T, and BN-2T-4R Airplanes AGENCY: Federal...

  6. Ultraviolet photoelectron spectra of (YC)2 @ C82 and Y2 @ C82

    NASA Astrophysics Data System (ADS)

    Hino, Shojun; Wanita, Norihiko; Iwasaki, Kentaro; Yoshimura, Daisuke; Akachi, Takao; Inoue, Takeshi; Ito, Yasuhiro; Sugai, Toshiki; Shinohara, Hisanori

    2005-11-01

    Ultraviolet photoelectron spectra (UPS) of metallofullerenes, (YC)2@C82 (III) and Y2@C82 (III) were measured using a synchrotron radiation light source. The spectral onset energy of (YC)2@C82 (III) was determined to be 0.8 eV below the Fermi level, and that of Y2@C82 (III) was 0.45eV , indicating the semiconductive nature of these metallofullerenes. The UPS consisted of numerous crests and troughs. Further, a change in intensity upon tuning the excitation energy was observed; however, the intensity of the change was not as large as those observed for other fullerenes. The UPS of two metallofullerenes basically resemble each other, although there are minute differences between them. The UPS of (YC)2@C82 (III) was easily reproduced by a simulated spectrum obtained by molecular orbital calculations assuming a C3v (8) cage structure with four additional electrons on the cage. A difference spectrum between the UPS of (YC)2@C82 (III) and Y2@C82 (III) indicates the existence of additional electrons on the cage of Y2@C82 .

  7. Hepatic SH2B1 and SH2B2 Regulate Liver Lipid Metabolism and VLDL Secretion in Mice

    PubMed Central

    Sheng, Liang; Liu, Yan; Jiang, Lin; Chen, Zheng; Zhou, Yingjiang; Cho, Kae Won; Rui, Liangyou

    2013-01-01

    SH2B1 is an SH2 and PH domain-containing adaptor protein. Genetic deletion of SH2B1 results in obesity, type 2 diabetes, and fatty liver diseases in mice. Mutations in SH2B1 are linked to obesity in humans. SH2B1 in the brain controls energy balance and body weight at least in part by enhancing leptin sensitivity in the hypothalamus. SH2B1 in peripheral tissues also regulates glucose and lipid metabolism, presumably by enhancing insulin sensitivity in peripheral metabolically-active tissues. However, the function of SH2B1 in individual peripheral tissues is unknown. Here we generated and metabolically characterized hepatocyte-specific SH2B1 knockout (HKO) mice. Blood glucose and plasma insulin levels, glucose tolerance, and insulin tolerance were similar between HKO, albumin-Cre, and SH2B1f/f mice fed either a normal chow diet or a high fat diet (HFD). Adult-onset deletion of SH2B1 in the liver either alone or in combination with whole body SH2B2 knockout also did not exacerbate HFD-induced insulin resistance and glucose intolerance. Adult-onset, but not embryonic, deletion of SH2B1 in the liver attenuated HFD-induced hepatic steatosis. In agreement, adult-onset deletion of hepatic SH2B1 decreased the expression of diacylglycerol acyltransferase-2 (DGAT2) and increased the expression of adipose triglyceride lipase (ATGL). Furthermore, deletion of liver SH2B1 in SH2B2 null mice attenuated very low-density lipoprotein (VLDL) secretion. These data indicate that hepatic SH2B1 is not required for the maintenance of normal insulin sensitivity and glucose metabolism; however, it regulates liver triacylglycerol synthesis, lipolysis, and VLDL secretion. PMID:24358267

  8. PTK2b function during fertilization of the mouse oocyte

    SciTech Connect

    Luo, Jinping; McGinnis, Lynda K.; Carlton, Carol; Beggs, Hilary E.; Kinsey, William H.

    2014-08-01

    Highlights: • PTK2b is expressed in oocytes and is activated following fertilization. • PTK2b suppression in oocytes prevents fertilization, but not parthenogenetic activation. • PTK2b suppression prevents the oocyte from fusing with or incorporating bound sperm. • PTK2b suppressed oocytes that fail to fertilize do not exhibit calcium oscillations. - Abstract: Fertilization triggers rapid changes in intracellular free calcium that serve to activate multiple signaling events critical to the initiation of successful development. Among the pathways downstream of the fertilization-induced calcium transient is the calcium-calmodulin dependent protein tyrosine kinase PTK2b or PYK2 kinase. PTK2b plays an important role in fertilization of the zebrafish oocyte and the objective of the present study was to establish whether PTK2b also functions in mammalian fertilization. PTK2b was activated during the first few hours after fertilization of the mouse oocyte during the period when anaphase resumption was underway and prior to the pronuclear stage. Suppression of PTK2b kinase activity in oocytes blocked sperm incorporation and egg activation although sperm-oocyte binding was not affected. Oocytes that failed to incorporate sperm after inhibitor treatment showed no evidence of a calcium transient and no evidence of anaphase resumption suggesting that egg activation did not occur. The results indicate that PTK2b functions during the sperm-egg fusion process or during the physical incorporation of sperm into the egg cytoplasm and is therefore critical for successful development.

  9. Expression of paired-like homeodomain transcription factor 2c (PITX2c) in epidermal keratinocytes

    SciTech Connect

    Shi, Ge; Sohn, Kyung-Cheol; Choi, Tae-Young; Choi, Dae-Kyoung; Lee, Sang-Sin; Ou, Bai-sheng; Kim, Sooil; Lee, Young Ho; Yoon, Tae-Jin; Kim, Seong-Jin; Lee, Young; Seo, Young-Joon; Lee, Jeung-Hoon; Kim, Chang Deok

    2010-11-15

    Paired-like homeodomain transcription factor 2 (PITX2) has been implicated as one of the genes responsible for Rieger syndrome. It has been also shown to play a central role during development. In this study, we investigated the functional role of PITX2 in keratinocyte differentiation. RT-PCR analysis showed that PITX2c isoform was predominantly expressed in a differentiation-dependent manner. Consistent with, immunohistochemical staining showed that PITX2 expression was increased in the upper layer of epidermis. When PITX2c was overexpressed in cultured keratinocytes by a recombinant adenovirus, the differentiation markers such as involucrin and loricrin were significantly increased at both mRNA and protein levels. In addition, PITX2c overexpression led to the decrease of cell growth, concomitantly with the upregulation of cell cycle-related genes p21. To investigate the effect of PITX2c in vivo, we microinjected PITX2c expression vector into zebrafish embryo. Interestingly, overexpression of PITX2c in zebrafish embryo led to the formation of horn-like structure and thickening of epidermis, together with the increase of keratin 8 (K8) expression. These results suggest that PITX2c has a role in proliferation and differentiation of epidermal keratinocytes.

  10. Success and pitfalls of the Sin-2C2H2-C2Bn-2Hn isolobal analogy: Depth and breadth of the boron connection

    NASA Astrophysics Data System (ADS)

    Zdetsis, Aristides D.

    2009-02-01

    The extent and depth of the so-called boron connection suggested recently by the present author [J. Chem. Phys. 128, 184305 (2008)] for the Sin-2C2H2-C2Bn-2Hn isovalent species [following similar connection of (Sin)2--(BnHn)2- dianions] are further investigated by considering larger species up to n =12 and additional isovalent moieties. Here we consider, using density functional and coupled clusters theory, isovalent Sin-2C2H2 and Gen-2C2H2 clusters, in comparison to the corresponding C2Bn-2Hn carboranes and to each other for n =3-8, 12. Special attention is given to the n =8 species, where the corresponding carborane is highly fluxional, and to n =12, where the "parent structures" of the corresponding (Si12)2- and (B12H12)2- dianions have drastically different symmetries. The structures generated by substitutions on (Si12)2-, as well as (B12H12)2-, are compared and interrelated for both C2B10H12 and Si10C2H12. The carborane generated from the Cs (Si12)2- dianion provides an illustrative example of carborane rearrangements, reverting after geometry optimization to the second lowest C2B10H12 meta isomer of C2v symmetry, 0.12 eV above the lowest energy para isomer. This demonstrates the amphidirectional character of the boron connection. It is found that n =8 is the upper limit of the n range in which the isolobal Sin-2C2H2-C2Bn-2Hn analogy is fully operative not only for the lowest but also for the second and third lowest energy states. For n ≤8 all three pairs of structures are isovalent, isostructural, and isolobal. For large values of n (n >8) the boron connection, although not fully isolobal, is still valid in a broader and more general sense, still providing deeper and broader fundamental understanding and insight for both species. It was also found that the Gen-2C2H2 clusters are not fully homologous (isolobal) neither to the isovalent Sin-2C2H2 clusters nor to the corresponding C2Bn-2Hn carboranes, preferring structures in which the two carbon atoms are

  11. Myosin heavy chain-2b transcripts and isoform are expressed in human laryngeal muscles.

    PubMed

    Smerdu, Vika; Cvetko, Erika

    2013-01-01

    Three fast myosin heavy chain (MyHC) isoforms, i.e. MyHC-2a, -2x and -2b, are expressed in skeletal muscles of smaller mammals. In contrast, only MyHC-2a and -2x have been revealed in humans so far. The expression of MyHC isoforms is known to be wider in the functionally more specialized laryngeal muscles. Though mRNA transcripts of the MyHC-2b gene were found to be expressed in certain human skeletal and laryngeal muscles, the corresponding isoform has not been demonstrated in these muscles. To our knowledge, we are the first to demonstrate not only the expression of MyHC-2b transcripts using an in situ hybridization technique but also the corresponding protein, i.e. the MyHC-2b isoform, in some human laryngeal muscles by immunohistochemistry but not by polyacrylamide gel electrophoresis. Using a set of antibodies specific to MyHC isoforms, we demonstrated that MyHC-2b was always co-expressed with the major MyHC isoforms, not only with the fast ones (MyHC-2a and -2x) but with the slow isoform (MyHC-1) as well.

  12. Knockdown of the sodium-dependent phosphate co-transporter 2b (NPT2b) suppresses lung tumorigenesis.

    PubMed

    Hong, Seong-Ho; Minai-Tehrani, Arash; Chang, Seung-Hee; Jiang, Hu-Lin; Lee, Somin; Lee, Ah-Young; Seo, Hwi Won; Chae, Chanhee; Beck, George R; Cho, Myung-Haing

    2013-01-01

    The sodium-dependent phosphate co-transporter 2b (NPT2b) plays an important role in maintaining phosphate homeostasis. In previous studies, we have shown that high dietary inorganic phosphate (Pi) consumption in mice stimulated lung tumorigenesis and increased NPT2b expression. NPT2b has also been found to be highly expressed in human lung cancer tissues. The association of high expression of NPT2b in the lung with poor prognosis in oncogenic lung diseases prompted us to test whether knockdown of NPT2b may regulate lung cancer growth. To address this issue, aerosols that contained small interfering RNA (siRNA) directed against NPT2b (siNPT2b) were delivered into the lungs of K-ras (LA1) mice, which constitute a murine model reflecting human lung cancer. Our results clearly showed that repeated aerosol delivery of siNPT2b successfully suppressed lung cancer growth and decreased cancer cell proliferation and angiogenesis, while facilitating apoptosis. These results strongly suggest that NPT2b plays a role lung tumorigenesis and represents a novel target for lung cancer therapy. PMID:24194864

  13. Activated astrocytes display increased 5-HT2a receptor expression in pathological states.

    PubMed

    Wu, C; Singh, S K; Dias, P; Kumar, S; Mann, D M

    1999-08-01

    In human brain tissues from patients dying with cerebral infarction, hypertensive encephalopathy, Alzheimer's disease, Huntington's disease, frontotemporal dementia, and Creutzfeldt-Jakob disease there is an activation of astrocytes. Such activated astrocytes display GFAP and strong 5-HT(2A), but not 5-HT(2B) or 5-HT(2C), receptor immunoreactivity; this 5-HT(2A) reaction has not been observed in normal, nonactivated astrocytes. It is suggested that an up-regulation of 5-HT(2A) receptors may be part of an early response reaction in astrocytes, possibly designed to maintain homeostasis or to induce secondary message pathways involving trophic factors or glycogenolysis. PMID:10415157

  14. Presence of histone H2B in Trypanosoma cruzi chromatin.

    PubMed

    Toro, G C; Wernstedt, C; Hellman, U; Galanti, N

    1993-01-01

    The organization of chromatin in protists presents some characteristic features. In Trypanosoma cruzi, no condensation of chromatin into chromosomes is observed during cell division. A systematic characterization of histones should provide information on this peculiar behaviour. Histone H2B from this parasite was characterized by selective dissociation from chromatin in 0.8 M NaCl, by its elution pattern in narrow-bore reversed phase high performance liquid chromatography, by polyacrylamide gel electrophoresis and by partial sequencing of its amino terminal domain. This chromosomal protein differs from histone H2B of other species. The first 12 amino acids are missing which explains its lower molecular weight when compared to human histone H2B. Correspondingly, the amino terminal domain of T. cruzi histone H2B is 25-30% shorter than other histones H2B. Moreover, three out of four acetylation sites present in human histone H2B are missing in T. cruzi histone H2B. The differences in size and in acceptor sites for acetylation of T. cruzi histone H2B when compared to human histone H2B may represent a functional feature to consider for the understanding of the chromatin cycle of condensation in this parasite.

  15. Preclinical studies on targeted delivery of multiple IFNα2b to HLA-DR in diverse hematologic cancers

    PubMed Central

    Rossi, Diane L.; Cardillo, Thomas M.; Stein, Rhona; Chang, Chien-Hsing

    2011-01-01

    The short circulating half-life and side effects of IFNα affect its dosing schedule and efficacy. Fusion of IFNα to a tumor-targeting mAb (mAb-IFNα) can enhance potency because of increased tumor localization and improved pharmacokinetics. We used the Dock-and-Lock method to generate C2-2b-2b, a mAb-IFNα comprising tetrameric IFNα2b site-specifically linked to hL243 (humanized anti–HLA-DR). In vitro, C2-2b-2b inhibited various B-cell lymphoma leukemia and myeloma cell lines. In most cases, this immunocytokine was more effective than CD20-targeted mAb-IFNα or a mixture comprising the parental mAb and IFNα. Our findings indicate that responsiveness depends on HLA-DR expression/density and sensitivity to IFNα and hL243. C2-2b-2b induced more potent and longer-lasting IFNα signaling compared with nontargeted IFNα. Phosphorylation of STAT1 was more robust and persistent than that of STAT3, which may promote apoptosis. C2-2b-2b efficiently depleted lymphoma and myeloma cells from whole human blood but also exhibited some toxicity to B cells, monocytes, and dendritic cells. C2-2b-2b showed superior efficacy compared with nontargeting mAb-IFNα, peginterferonalfa-2a, or a combination of hL243 and IFNα, using human lymphoma and myeloma xenografts. These results suggest that C2-2b-2b should be useful in the treatment of various hematopoietic malignancies. PMID:21680794

  16. Superposition of quantum and classical rotational motions in Sc2C2@C84 fullerite

    NASA Astrophysics Data System (ADS)

    Michel, K. H.; Verberck, B.; Hulman, M.; Kuzmany, H.; Krause, M.

    2007-02-01

    The superposition of the quantum rotational motion (tunneling) of the encapsulated Sc2C2 complex with the classical rotational motion of the surrounding C84 molecule in a powder crystal of Sc2C2@C84 fullerite is investigated by theory. Since the quantum rotor is dragged along by the C84 molecule, any detection method which couples to the quantum rotor (in casu the C2 bond of the Sc2C2 complex) also probes the thermally excited classical motion (uniaxial rotational diffusion and stochastic meroaxial jumps) of the surrounding fullerene. The dynamic rotation-rotation response functions in frequency space are obtained as convolutions of quantum and classical dynamic correlation functions. The corresponding Raman scattering laws are derived, and the overall shape of the spectra and the width of the resonance lines are studied as functions of temperature. The results of the theory are confronted with experimental low-frequency Raman spectra on powder crystals of Sc2C2@C84 [M. Krause et al., Phys. Rev. Lett. 93, 137403 (2004)]. The agreement of theory with experiment is very satisfactory in a broad temperature range.

  17. Canine parvovirus type 2c identified from an outbreak of severe gastroenteritis in a litter in Sweden.

    PubMed

    Sutton, David; Vinberg, Carina; Gustafsson, Agneta; Pearce, Jacqueline; Greenwood, Neil

    2013-01-01

    A litter of recently-vaccinated puppies in Sweden experienced signs of severe haemorrhagic gastroenteritis. Canine parvovirus (CPV) was suspected as the cause of this outbreak on the basis of the clinical signs and the presence of parvoviral antigen in the faeces from one of the affected pups - confirmed using a commercial in-clinic faecal antigen ELISA test kit. A concern was raised about whether the vaccine (which contained a live, attenuated strain of CPV) could have caused the disease and so further faecal samples from the affected pups were submitted for laboratory virus isolation and identification.On cell culture, two out of four faecal samples were found to be virus-positive. This was confirmed as being canine parvovirus by immuno-staining with CPV specific monoclonal antibody. The virus was then tested using a series of PCR probes designed to confirm the identity of CPV and to distinguish the unique vaccine strain from field virus. This confirmed that the virus was indeed CPV but that it was not vaccine strain. The virus was then typed by sequencing the 426 amino acid region of the capsid gene which revealed this to be a type 2c virus.Since its emergence in the late 1970s, canine parvovirus 2 (CPV2) has spread worldwide and is recognised as an important canine pathogen in all countries. The original CPV2 rapidly evolved into two antigenic variants, CPV2a and CPV2b, which progressively replaced the original CPV2. More recently a new antigenic variant, CPV2c, has appeared. To date this variant has been identified in many countries worldwide but there have been no reports yet of its presence in any Scandinavian countries. This case report therefore represents the first published evidence of the involvement of CPV2c in a severe outbreak of typical haemorrhagic gastroenteritis in a susceptible litter of pups in Scandinavia.

  18. Differential effects of enrichment on learning and memory function in NR2B transgenic mice.

    PubMed

    Tang, Y P; Wang, H; Feng, R; Kyin, M; Tsien, J Z

    2001-11-01

    It has been known that environmental enrichment leads to better learning and memory in mice. However, the molecular mechanisms are not known. In this study, we used the 10th-12th of the NR2B transgenic (Tg) lines, in which the NMDA receptor function is enhanced via the NR2B subunit transgene in neurons of the forebrain, to test the hypothesis of the involvement of NMDA receptor function in enrichment-induced better learning and memory. Consistent with our previous results, both larger long-term potentiation (LTP) in the hippocampus and superior learning and memory were observed in naive NR2B Tg mice even after the 10th-12th generation of breeding. After enrichment, wild-type mice exhibited overall improvement in their performances in contextual and cued conditioning, fear extinctions, and novel object recognition tasks. Interestingly, the same enrichment procedures could not further increase the performance of NR2B Tg mice in contextual conditioning, cued conditioning, or fear extinction, thereby indicating that enhanced NMDA receptor function can occlude these enrichment effects. However, we found that in the novel object recognition task enriched NR2B Tg mice exhibited much longer recognition memory (up to 1 week), compared to that (up to 3 days) in naive NR2B Tg mice. Furthermore, our biochemical experiments showed that enrichment significantly increased protein levels of GluR1, NR2B, and NR2A subunits of glutamate receptors in both wild-type and NR2B Tg mice. Therefore, our results suggest an interactive nature of molecular pathways involved in both environmental and genetic NMDA receptor manipulations for enhancing learning and memory.

  19. In silico analysis of Brucella abortus Omp2b and in vitro expression of SOmp2b

    PubMed Central

    2016-01-01

    Purpose At present, there is no vaccine available for the prevention of human brucellosis. Brucella outer membrane protein 2b (Omp2b) is a 36 kD porin existed in common Brucella pathogens and it is considered as priority antigen for designing a new subunit vaccine. Materials and Methods In the current study, we aimed to predict and analyze the secondary and tertiary structures of the Brucella abortus Omp2b protein, and to predict T-cell and B-cell epitopes with the help of bioinformatics tools. Subsequently, cloning and expression of the short form of Omp2b (SOmp2b) was performed using pET28a expression vector and Escherichia coli BL21 host, respectively. The recombinant SOmp2b (rSOmp2b) was purified with Ni-NTA column. Results The recombinant protein was successfully expressed in E. coli host and purified under denaturation conditions. The yield of the purified rSOmp2b was estimated by Bradford method and found to be 220 µg/mL of the culture. Conclusion Our results indicate that Omp2b protein has a potential to induce both B-cell– and T-cell–mediated immune responses and it can be evaluated as a new subunit vaccine candidate against brucellosis. PMID:26866027

  20. Increased extrasynaptic GluN2B expression is involved in cognitive impairment after isoflurane anesthesia

    PubMed Central

    LI, LUNXU; LI, ZHENGQIAN; CAO, YIYUN; FAN, DONGSHENG; CHUI, DEHUA; GUO, XIANGYANG

    2016-01-01

    There is increasing concern regarding the postoperative cognitive dysfunction (POCD) in the aging population, and general anesthetics are believed to be involved. Isoflurane exposure induced increased N-methyl-D-aspartic acid receptor (NMDAR) GluN2B subunit expression following anesthesia, which was accompanied by alteration of the cognitive function. However, whether isoflurane affects this expression in different subcellular compartments, and is involved in the development of POCD remains to be elucidated. The aims of the study were to investigate the effects of isoflurane on the expression of the synaptic and extrasynaptic NMDAR subunits, GluN2A and GluN2B, as well as the associated alteration of cognitive function in aged rats. The GluN2B antagonist, Ro25–6981, was given to rats exposed to isoflurane to determine the role of GluN2B in the isoflurane-induced alteration of cognitive function. The results showed that spatial learning and memory tested in the Morris water maze (MWM) was impaired at least 7 days after isoflurane exposure, and was returned to control levels 30 days thereafter. Ro25-6981 treatment can alleviate this impairment. Extrasynaptic GluN2B protein expression, but not synaptic GluN2B or GluN2A, increased significantly after isoflurane exposure compared to non-isoflurane exposure, and returned to control levels approximately 30 days thereafter. The results of the present study indicated that isoflurane induced the prolonged upregulation of extrasynaptic GluN2B expression after anesthesia and is involved in reversible cognitive impairment. PMID:27347033

  1. Building Customized University-to-Business (U2B) Partnerships

    ERIC Educational Resources Information Center

    Irvine, George; Verma, Lisa

    2013-01-01

    Continuing education (CE) units throughout the United States have successfully built University-to-Business (U2B) partnerships to provide greater value to their community partners and to increase revenue for the university. Our experience in building U2B partnerships and feedback from our partners--businesses, corporations, state agencies, and…

  2. Slow epidemic of lymphogranuloma venereum L2b strain.

    PubMed

    Spaargaren, Joke; Schachter, Julius; Moncada, Jeanne; de Vries, Henry J C; Fennema, Han S A; Peña, A Salvador; Coutinho, Roel A; Morré, Servaas A

    2005-11-01

    We traced the Chlamydia trachomatis L2b variant in Amsterdam and San Francisco. All recent lymphogranuloma venereum cases in Amsterdam were caused by the L2b variant. This variant was also present in the 1980s in San Francisco. Thus, the current "outbreak" is most likely a slowly evolving epidemic.

  3. 1-, 3- and 8-substituted-9-deazaxanthines as potent and selective antagonists at the human A2B adenosine receptor.

    PubMed

    Stefanachi, Angela; Brea, Jose Manuel; Cadavid, Maria Isabel; Centeno, Nuria B; Esteve, Cristina; Loza, Maria Isabel; Martinez, Ana; Nieto, Rosa; Raviña, Enrique; Sanz, Ferran; Segarra, Victor; Sotelo, Eddy; Vidal, Bernat; Carotti, Angelo

    2008-03-15

    A large series of piperazin-, piperidin- and tetrahydroisoquinolinamides of 4-(1,3-dialkyl-9-deazaxanthin-8-yl)phenoxyacetic acid were prepared through conventional or multiple parallel syntheses and evaluated for their binding affinity at the recombinant human adenosine receptors, chiefly at the hA(2B) and hA(2A) receptor subtypes. Several ligands endowed with high binding affinity at hA(2B) receptors, excellent selectivity over hA(2A) and hA(3) and a significant, but lower, selectivity over hA(1) were identified. Among them, piperazinamide derivatives 23 and 52, and piperidinamide derivative 69 proved highly potent at hA(2B) (K(i)=11, 2 and 5.5 nM, respectively) and selective towards hA(2A) (hA(2A)/hA(2B) SI=912, 159 and 630, respectively), hA(3) (hA(3)/hA(2B) SI=>100, 3090 and >180, respectively) and hA(1) (hA(1)/hA(2B) SI=>100, 44 and 120, respectively), SI being the selectivity index. A number of selected ligands tested in functional assays in vitro showed very interesting antagonist activities and efficacies at both A(2A) and A(2B) receptor subtypes, with pA(2) values close to the corresponding pK(i)s. Structure-affinity and structure-selectivity relationships suggested that the binding potency at the hA(2B) receptor may be increased by lipophilic substituents at the N4-position of piperazinamides and that an ortho-methoxy substituent at the 8-phenyl ring and alkyl groups at N1 larger than the ones at N3, in the 9-deazaxanthine ring, may strongly enhance the hA(2A)/hA(2B) SI. PMID:18226909

  4. Monoclonal Antibodies Against NS2B of Japanese Encephalitis Virus.

    PubMed

    Dong, Qian; Xu, Qiuping; Ruan, Xindi; Huang, Shaomei; Cao, Shengbo

    2015-04-01

    Japanese encephalitis (JE) is one of the most important viral encephalitis, caused by the Japanese encephalitis virus (JEV). The function of non-structural protein 2B (NS2B) mostly remains unclear. In our study, NS2B of Japanese encephalitis virus (JEV) was expressed in Escherichia coli and purified by dialysis. After fusing mouse myeloma cell line SP2/0 with spleen lymphocytes from NS2B protein immunized mice, three clones of monoclonal antibodies (MAbs), named 1B9, 3E12, and 4E6, were generated. The specificity and sensitivity of MAbs were demonstrated by ELISA, indirect immunofluorescence assay, and Western blot. These MAbs will be useful in further exploration of the functions of NS2B and the pathogenesis of Japanese encephalitis virus. PMID:25897607

  5. Effect of tamoxifen on the enzymatic activity of human cytochrome CYP2B6.

    PubMed

    Sridar, Chitra; Kent, Ute M; Notley, Lisa M; Gillam, Elizabeth M J; Hollenberg, Paul F

    2002-06-01

    Tamoxifen is primarily used in the treatment of breast cancer. It has been approved as a chemopreventive agent for individuals at high risk for this disease. Tamoxifen is metabolized to a number of different products by cytochrome P450 enzymes. The effect of tamoxifen on the enzymatic activity of bacterially expressed human cytochrome CYP2B6 in a reconstituted system has been investigated. The 7-ethoxy-4-(trifluoromethyl)coumarin O-deethylation activity of purified CYP2B6 was inactivated by tamoxifen in a time- and concentration-dependent manner. Enzymatic activity was lost only in samples that were incubated with both tamoxifen and NADPH. The inactivation was characterized by a K(I) of 0.9 microM, a k(inact) of 0.02 min(-1), and a t(1/2) of 34 min. The loss in the 7-ethoxy-4-(trifluoromethyl)coumarin O-deethylation activity did not result in a similar percentage loss in the reduced carbon monoxide spectrum, suggesting that the heme moiety was not the major site of modification. The activity of CYP2B6 was not recovered after removal of free tamoxifen using spin column gel filtration. The loss in activity seemed to be due to a modification of the CYP2B6 and not reductase because adding fresh reductase back to the inactivated samples did not restore enzymatic activity. A reconstituted system containing purified CYP2B6, NADPH-reductase, and NADPH-generating system was found to catalyze tamoxifen metabolism to 4-OH-tamoxifen, 4'-OH-tamoxifen, and N-desmethyl-tamoxifen as analyzed by high-performance liquid chromatography analysis. Preliminary studies showed that tamoxifen had no effect on the activities of CYP1B1 and CYP3A4, whereas CYP2D6 and CYP2C9 exhibited a 25% loss in enzymatic activity. PMID:12023523

  6. Importance of the GluN2B Carboxy-Terminal Domain for Enhancement of Social Memories

    ERIC Educational Resources Information Center

    Jacobs, Stephanie; Wei, Wei; Wang, Deheng; Tsien, Joe Z.

    2015-01-01

    The N-methyl-D-aspartate (NMDA) receptor is known to be necessary for many forms of learning and memory, including social recognition memory. Additionally, the GluN2 subunits are known to modulate multiple forms of memory, with a high GluN2A:GluN2B ratio leading to impairments in long-term memory, while a low GluN2A:GluN2B ratio enhances some…

  7. Isolation of 1,4-Li(2)-C(6)H(4) and its reaction with [(Ph(3)P)AuCl].

    PubMed

    Flower, Kevin R; McGown, A T; Miles, Philip J; Pritchard, Robin G; Warren, John E

    2010-04-14

    The difficulty in generating 1,4-Li2-C6H4 utilising the lithium halogen exchange reaction on 1,4-Br2-C6H4, 1,4-I2-C6H4 and 1-Br-4-I-C6H4 is revisited and only on treatment of 1,4-I2-C6H4 with 2 molar equivalents of n-BuLi can 1,4-Li2-C6H4 1 be isolated in excellent yield. Treatment of 1 with two equivalents of [ClAu(PPh3)] gives [1,4-(Ph3PAu)2-C6H4] 2a in excellent yield. Subsequent treatment of 2a with 2.5 molar equivalents of PPh2Me, PPhMe2 or PMe3 affords the PPh3 substituted compounds [1,4-(LAu)2-C6H4] (L = PPh2Me 2b, PPhMe2 2c, PMe3 2d) in essentially quantitative yields. On treatment of 1,4-Br2-C6H4 or 1-Br-4-I-C6H4 with 2 molar equivalents of n-BuLi only mono-lithiation takes place to give 1-Br-4-Li-C6H4 3 as shown through the isolation of essentially 1:1 molar equivalents of Ph2PC6H4-4-Br and Ph2PBu on treatment with 2 molar equivalents of ClPPh2. Treatment of 3, prepared by lithium/iodine exchange on 1-Br-4-I-C6H4, with [ClAu(PPh3)] affords [(Ph3P)Au(C6H4-4-Br)] 4 as expected and in addition [(Ph3P)Au(n-Bu)(C6H4-4-Br)2] 5, indicating the straightforward chloride/aryl exchange at gold may proceed in competition with oxidative addition of the n-BuI, generated in the initial lithium/iodine exchange reaction, to some aurate complex Li[Au(C6H4-4-Br)2] 6 formed in situ followed by reductive elimination of Br-C6H4-4-n-Bu in a manner that mimics lithium diorganocuprate chemistry. All of the gold-containing compounds have been spectroscopically characterised by 1H and 31P-{1H} NMR and in addition compounds 2a-d and 5 by single crystal X-ray diffraction studies. The solid state structures observed for 2a-d are dictated by non-conventional hydrogen bonding and the packing requirements of the phosphine ligands. For 2a and 2b there is no close Au...Au approach, however for 2c and 2d the reduction in the number of phenyl rings allows the formation of Au...Au contacts. For 2c and 2d the extended structures appear to be helical chains with Au...Au contact parameters of 3

  8. Isolation of 1,4-Li(2)-C(6)H(4) and its reaction with [(Ph(3)P)AuCl].

    PubMed

    Flower, Kevin R; McGown, A T; Miles, Philip J; Pritchard, Robin G; Warren, John E

    2010-04-14

    The difficulty in generating 1,4-Li2-C6H4 utilising the lithium halogen exchange reaction on 1,4-Br2-C6H4, 1,4-I2-C6H4 and 1-Br-4-I-C6H4 is revisited and only on treatment of 1,4-I2-C6H4 with 2 molar equivalents of n-BuLi can 1,4-Li2-C6H4 1 be isolated in excellent yield. Treatment of 1 with two equivalents of [ClAu(PPh3)] gives [1,4-(Ph3PAu)2-C6H4] 2a in excellent yield. Subsequent treatment of 2a with 2.5 molar equivalents of PPh2Me, PPhMe2 or PMe3 affords the PPh3 substituted compounds [1,4-(LAu)2-C6H4] (L = PPh2Me 2b, PPhMe2 2c, PMe3 2d) in essentially quantitative yields. On treatment of 1,4-Br2-C6H4 or 1-Br-4-I-C6H4 with 2 molar equivalents of n-BuLi only mono-lithiation takes place to give 1-Br-4-Li-C6H4 3 as shown through the isolation of essentially 1:1 molar equivalents of Ph2PC6H4-4-Br and Ph2PBu on treatment with 2 molar equivalents of ClPPh2. Treatment of 3, prepared by lithium/iodine exchange on 1-Br-4-I-C6H4, with [ClAu(PPh3)] affords [(Ph3P)Au(C6H4-4-Br)] 4 as expected and in addition [(Ph3P)Au(n-Bu)(C6H4-4-Br)2] 5, indicating the straightforward chloride/aryl exchange at gold may proceed in competition with oxidative addition of the n-BuI, generated in the initial lithium/iodine exchange reaction, to some aurate complex Li[Au(C6H4-4-Br)2] 6 formed in situ followed by reductive elimination of Br-C6H4-4-n-Bu in a manner that mimics lithium diorganocuprate chemistry. All of the gold-containing compounds have been spectroscopically characterised by 1H and 31P-{1H} NMR and in addition compounds 2a-d and 5 by single crystal X-ray diffraction studies. The solid state structures observed for 2a-d are dictated by non-conventional hydrogen bonding and the packing requirements of the phosphine ligands. For 2a and 2b there is no close Au...Au approach, however for 2c and 2d the reduction in the number of phenyl rings allows the formation of Au...Au contacts. For 2c and 2d the extended structures appear to be helical chains with Au...Au contact parameters of 3

  9. Substrate- and pH-Specific Antifolate Transport Mediated by Organic Anion-Transporting Polypeptide 2B1 (OATP2B1-SLCO2B1)

    PubMed Central

    Visentin, Michele; Chang, Min-Hwang; Romero, Michael F.; Zhao, Rongbao

    2012-01-01

    Human organic anion-transporting polypeptide (OATP) 2B1 (OATP-B; SLCO2B1) is expressed in the apical membrane of the small intestine and the hepatocyte basolateral membrane and transports structurally diverse organic anions with a wide spectrum of pH sensitivities. This article describes highly pH-dependent OATP2B1-mediated antifolate transport and compares this property with that of sulfobromophthalein (BSP), a preferred OATP2B1 substrate. At pH 5.5 and low substrate concentrations (∼2.5 μM), only [3H]pemetrexed influx [in contrast to methotrexate (MTX), folic acid, and reduced folates] could be detected in OATP2B1-transfected HeLa R1-11 cells that lack endogenous folate-specific transporters. Influx was optimal at pH 4.5 to 5.5, falling precipitously with an increase in pH >6.0; BSP influx was independent of pH. Influx of both substrates at low pH was markedly inhibited by the proton ionophore 4-(trifluoromethoxy)phenylhydrazone; BSP influx was also suppressed at pH 7.4. At 300 μM MTX, influx was one-third that of pemetrexed; influx of folic acid, (6S)5-methyltetrahydrofolate, or (6S)5-formyltetrahydrofolate was not detected. There were similar findings in OATP2B1-expressing Xenopus laevis oocytes. The pemetrexed influx Km was ∼300 μM; the raltitrexed influx Ki was ∼70 μM at pH 5.5. Stable expression of OAPT2B1 in HeLa R1-11 cells resulted in substantial raltitrexed, but modest pemetrexed, growth inhibition consistent with their affinities for this carrier. Hence, OATP2B1 represents a low-affinity transport route for antifolates (relative affinities: raltitrexed > pemetrexed > MTX) at low pH. In contrast, the high affinity of this transporter for BSP relative to antifolates seems to be intrinsic to its binding site and independent of the proton concentration. PMID:22021325

  10. Anisotropy of the Vortex Magnetic Field Distribution in LuNi2B2

    NASA Astrophysics Data System (ADS)

    Eskildsen, M. R.; Debeer-Schmitt, L.; Rovira, K.; Jenkins, N.; Dewhurst, C. D.; Bud'Ko, S. L.; Canfield, P. C.

    2008-03-01

    It is well known that the vortex lattice (VL) symmetry and orientation in type-II superconductors is very sensitive to any anisotropy within the screening current plane. A classic example is the sequence of transitions from hexagonal to rhombic to square symmetry, which was first observed in the borocarbide superconductors and explained by a Fermi surface anisotropy coupled with the non-local electrodynamics responsible for vortex-vortex interactions. Recently, however, this is mounting experimental evidence for a strong gap anisotropy and possible point nodes in the basal plane of these materials. Here we report on small-angle neutron scattering studies of the VL in a carefully annealed, high quality LuNi2B2C single crystal, which permitted us to measure the VL form factor for a large number of reflections. These measurements allow a reconstruction of the real space profile of the magnetic field around the vortices, reflecting the basal plane anisotropy of the screening currents in LuNi2B2C. The results will be compared to predictions for both Fermi surface and gap anisotropies, and will serve as a valuable reference for more complicated compounds as e.g. Sr2RuO4, heavy fermions and high-Tc's.

  11. Probing biased/partial agonism at the G protein-coupled A(2B) adenosine receptor.

    PubMed

    Gao, Zhan-Guo; Balasubramanian, Ramachandran; Kiselev, Evgeny; Wei, Qiang; Jacobson, Kenneth A

    2014-08-01

    G protein-coupled A(2B) adenosine receptor (AR) regulates numerous important physiological functions, but its activation by diverse A(2B)AR agonists is poorly profiled. We probed potential partial and/or biased agonism in cell lines expressing variable levels of endogenous or recombinant A(2B)AR. In cAMP accumulation assays, both 5'-substituted NECA and C2-substituted MRS3997 are full agonists. However, only 5'-substituted adenosine analogs are full agonists in calcium mobilization, ERK1/2 phosphorylation and β-arrestin translocation. A(2B)AR overexpression in HEK293 cells markedly increased the agonist potency and maximum effect in cAMP accumulation, but less in calcium and ERK1/2. A(2B)AR siRNA silencing was more effective in reducing the maximum cAMP effect of non-nucleoside agonist BAY60-6583 than NECA's. A quantitative 'operational model' characterized C2-substituted MRS3997 as either balanced (cAMP accumulation, ERK1/2) or strongly biased agonist (against calcium, β-arrestin). N⁶-substitution biased against ERK1/2 (weakly) and calcium and β-arrestin (strongly) pathways. BAY60-6583 is ERK1/2-biased, suggesting a mechanism distinct from adenosine derivatives. BAY60-6583, as A(2B)AR antagonist in MIN-6 mouse pancreatic β cells expressing low A(2B)AR levels, induced insulin release. This is the first relatively systematic study of structure-efficacy relationships of this emerging drug target.

  12. Absence of the functional Myosin heavy chain 2b isoform in equine skeletal muscles.

    PubMed

    Chikuni, Koichi; Muroya, Susumu; Nakajima, Ikuyo

    2004-05-01

    Nucleotide sequences which included the full coding region for three types of myosin heavy chain (MyHC) isoforms were determined from equine skeletal muscles. The deduced amino acid sequences were 1937, 1938, and 1935 residues for the MyHC-2a, -2x, and -slow, respectively. No MyHC-2b isoform was amplified from the equine muscle cDNA except for one pseudogene fragment. One nucleotide was inserted in the coding region of the equine pseudogene product, a minute amount of which was expressed in the skeletal muscle. The 596 bp sequence of the equine MyHC pseudogene was categorized into the MyHC-2b genes on the phylogenetic tree of the mammalian MyHC genes. These results suggest that an ancestral MyHC-2b gene had lost its function and changed to a pseudogene during the course of horse history. The MyHC genes in some ungulates were analyzed through the PCR amplifications using the MyHC isoform-specific primers to confirm the presence of the MyHC-2b and -2x genes. The exon coding the 3' untranslated region of the MyHC-2x was successfully amplified from the all ungulates examined; however, that of the MyHC-2b gene was amplified only from horses, pigs and lesser mouse deer. The PCR analyses from rhinoceros, sika deer, moose, giraffes, water buffalo, bovine, Japanese serow and sheep genes implied the absence of the MyHC-2b-specific sequence in their genomes. These results suggest that the MyHC-2b gene independently lost its function in some ungulate species.

  13. Reduced Toxicity of Shiga Toxin (Stx) Type 2c in Mice Compared to Stx2d Is Associated with Instability of Stx2c Holotoxin.

    PubMed

    Bunger, Joshua C; Melton-Celsa, Angela R; Maynard, Ernest L; O'Brien, Alison D

    2015-06-23

    Shiga toxin (Stx) is an AB5 ribotoxin made by Stx-producing Escherichia coli (STEC). These organisms cause diarrhea, hemorrhagic colitis and the hemolytic uremic syndrome. STEC make two types of Stxs, Stx1 and/or Stx2. Stx2 has one prototype (a) and six subtypes (b-g), but only STEC that make Stx2a, and/or Stx2c, or Stx2d are associated with severe disease. However, Stx2c is about 10-fold less toxic than Stx2d in vivo despite only two amino acid differences in the A subunit at positions 291 and 297. We made mutations at these two sites to create intermediate toxins between Stx2c and Stx2d, and determined the 50% cytotoxic dose on Vero cells before and after heat treatment, and the 50% lethal dose in mice of the toxins. We found that serine 291 was associated with increased toxicity in vivo and that either amino acid change from that in Stx2c to that in Stx2d increased heat stability. We also assessed the secondary structure of Stx2c and Stx2d by circular dichroism (CD) spectroscopy. The CD studies suggest that Stx2c has a less-ordered secondary structure than Stx2d. We conclude that both amino acids at positions 291 and 297 in Stx2c contribute to its decreased stability and in vivo toxicity compared to Stx2d.

  14. Secretion of human interferon alpha 2b by Streptomyces lividans.

    PubMed

    Pimienta, E; Fando, R; Sánchez, J C; Vallin, C

    2002-02-01

    Biologically active human interferon alpha 2b (HuIFNalpha-2b) was secreted into the culture medium by Streptomyces lividans transformed with recombinant plasmids coding for HuIFNalpha-2b fused to the Streptomyces exfoliatus M11 lipase A signal sequence. Levels were low, 15 or 100 ng/ml, depending on the plasmid used. Neither processed nor unprocessed HuIFNalpha-2b was detected in cell lysates of the transformants secreting the recombinant product. However, the secreted recombinant product was found to partially degrade when cultures reached the stationary phase by the action of an, as yet, unidentified mycelium-associated factor. Experimental evidence suggests that the degrading factor is related to mycelium-associated proteolytic activity.

  15. Independent Review of AFC 2A, 2B, and 2E ATR Irradiation Tests

    SciTech Connect

    M. Cappiello; R. Hobbins; K. Penny; L. Walters

    2014-01-01

    As part of the Department of Energy Advanced Fuel Cycle program, a series of fuels development irradiation tests have been performed in the Advanced Test Reactor (ATR) at the Idaho National Laboratory. These tests are providing excellent data for advanced fuels development. The program is focused on the transmutation of higher actinides which best can be accomplished in a sodium-cooled fast reactor. Because a fast test reactor is no longer available in the US, a special test vehicle is used to achieve near-prototypic fast reactor conditions (neutron spectra and temperature) for use in ATR (a water-cooled thermal reactor). As part of the testing program, there were many successful tests of advanced fuels including metals and ceramics. Recently however, there have been three experimental campaigns using metal fuels that experienced failure during irradiation. At the request of the program, an independent review committee was convened to review the post-test analyses performed by the fuels development team, to assess the conclusions of the team for the cause of the failures, to assess the adequacy and completeness of the analyses, to identify issues that were missed, and to make recommendations for improvements in the design and operation of future tests. Although there is some difference of opinion, the review committee largely agreed with the conclusions of the fuel development team regarding the cause of the failures. For the most part, the analyses that support the conclusions are sufficient.

  16. SETDB1 HISTONE METHYLTRANSFERASE REGULATES MOOD-RELATED BEHAVIORS AND EXPRESSION OF THE NMDA RECEPTOR SUBUNIT NR2B

    PubMed Central

    Jiang, Yan; Jakovcevski, Mira; Bharadwaj, Rahul; Connor, Caroline; Schroeder, Frederick A.; Lin, Cong L.; Straubhaar, Juerg; Martin, Gilles; Akbarian, Schahram

    2010-01-01

    Histone methyltransferases specific for the histone H3-lysine 9 (H3K9) residue, including Setdb1 (Set domain, bifurcated 1)/Eset/Kmt1e are associated with repressive chromatin remodeling and expressed in adult brain, but potential effects on neuronal function and behavior remain unexplored. Here, we report that transgenic mice with increased Setdb1 expression in adult forebrain neurons show antidepressant-like phenotypes in behavioral paradigms for anhedonia, despair and learned helplessness. Chromatin immunoprecipitation in conjunction with DNA tiling arrays (ChIP-chip) revealed that genomic occupancies of neuronal Setdb1 are limited to less than 1% of annotated genes, which include the NMDA receptor subunit NR2B/Grin2B and other ionotropic glutamate receptor genes. Chromatin conformation capture (“3C”) and Setdb1-ChIP revealed a loop formation tethering the NR2B/Grin2b promoter to the Setdb1 target site positioned 30Kb downstream of the transcription start site. In hippocampus and ventral striatum, two key structures in the neuronal circuitry regulating mood-related behaviors, Setdb1-mediated repressive histone methylation at NR2B/Grin2b was associated with decreased NR2B expression and EPSP insensitivity to pharmacological blockade of NR2B, and accelerated NMDA receptor desensitization consistent with a shift in NR2A/B subunit ratios. In wildtype mice, systemic treatment with the NR2B antagonist, Ro-256981, and hippocampal siRNA-mediated NR2B/Grin2b knockdown, resulted in behavioral changes similar to those elicited by the Setdb1 transgene. Together, these findings point to a role for neuronal Setdb1 in the regulation of affective and motivational behaviors through repressive chromatin remodeling at a select set of target genes, resulting in altered NMDA receptor subunit composition and other molecular adaptations. PMID:20505083

  17. Signal Transduction Mechanism for Serotonin 5-HT2B Receptor-Mediated DNA Synthesis and Proliferation in Primary Cultures of Adult Rat Hepatocytes.

    PubMed

    Naito, Kota; Tanaka, Chizuru; Mitsuhashi, Manami; Moteki, Hajime; Kimura, Mitsutoshi; Natsume, Hideshi; Ogihara, Masahiko

    2016-01-01

    The involvement of serotonin (5-hydroxytryptamine; 5-HT) and the 5-HT2 receptor subtypes in the induction of DNA synthesis and proliferation was investigated in primary cultures of adult rat hepatocytes to elucidate the intracellular signal transduction mechanisms. Hepatocyte parenchymal cells maintained in a serum-free, defined medium, synthesized DNA and proliferated in the presence of 5-HT or a selective 5-HT2B receptor agonist, BW723C86, but not in the presence of 5-HT2A, or 5-HT2C receptor agonists (TCB-2 and CP809101, respectively), in a time- and dose-dependent manner. A selective 5-HT2B receptor antagonist, LY272015 (10(-7) M), and a specific phospholipase C (PLC) inhibitor, U-73122 (10(-6) M), as well as specific inhibitors of growth-related signal transducers-including AG1478, LY294002, PD98059, and rapamycin-completely inhibited 5-HT (10(-6) M)- or BW723C86 (10(-6) M)-induced hepatocyte DNA synthesis and proliferation. Both 5-HT and BW723C86 were shown to significantly stimulate the phosphorylation of epidermal growth factor (EGF)/transforming growth factor (TGF)-α receptor tyrosine kinase (p175 kDa) and extracellular signal-regulated kinase (ERK) 2 on Western blot analysis. These results suggest that the proliferative mechanism of activating 5-HT is mediated mainly through 5-HT2B receptor-stimulated Gq/PLC and EGF/TGF-α-receptor/phosphatidylinositol 3-kinase (PI3K)/ERK2/mammalian target of rapamycin (mTOR) signaling pathways in primary cultured hepatocytes.

  18. PTK2b function during fertilization of the mouse oocyte.

    PubMed

    Luo, Jinping; McGinnis, Lynda K; Carlton, Carol; Beggs, Hilary E; Kinsey, William H

    2014-08-01

    Fertilization triggers rapid changes in intracellular free calcium that serve to activate multiple signaling events critical to the initiation of successful development. Among the pathways downstream of the fertilization-induced calcium transient is the calcium-calmodulin dependent protein tyrosine kinase PTK2b or PYK2 kinase. PTK2b plays an important role in fertilization of the zebrafish oocyte and the objective of the present study was to establish whether PTK2b also functions in mammalian fertilization. PTK2b was activated during the first few hours after fertilization of the mouse oocyte during the period when anaphase resumption was underway and prior to the pronuclear stage. Suppression of PTK2b kinase activity in oocytes blocked sperm incorporation and egg activation although sperm-oocyte binding was not affected. Oocytes that failed to incorporate sperm after inhibitor treatment showed no evidence of a calcium transient and no evidence of anaphase resumption suggesting that egg activation did not occur. The results indicate that PTK2b functions during the sperm-egg fusion process or during the physical incorporation of sperm into the egg cytoplasm and is therefore critical for successful development.

  19. Activation of 5-HT(2C) receptors in the dorsal periaqueductal gray increases antinociception in mice exposed to the elevated plus-maze.

    PubMed

    Baptista, Daniela; Nunes-de-Souza, Ricardo Luiz; Canto-de-Souza, Azair

    2012-11-01

    Several findings have pointed to the role of the dorsal periaqueductal gray (dPAG) serotonin 5-HT(1A) and 5-HT(2A-C) receptor subtypes in the modulation of defensive behavior in animals exposed to the elevated plus-maze (EPM). Besides displaying anxiety-like behavior, rodents also exhibit antinociception in the EPM. This study investigated the effects of intra-dPAG injections of 5-HT(1A) and 5-HT(2B/2C) receptor ligands on EPM-induced antinociception in mice. Male Swiss mice received 0.1 μl intra-dPAG injections of vehicle, 5.6 and 10 nmol of 8-OHDPAT, a 5-HT(1A) receptor agonist (Experiment 1), or 0.01, 0.03 and 0.1 nmol of mCPP, a 5-HT(2B/2C) receptor agonist (Experiment 2). Five minutes later, each mouse received an intraperitoneal injection of 0.6% acetic acid (0.1 ml/10 g body weight; nociceptive stimulus) and was individually confined in the open (OA) or enclosed (EA) arms of the EPM for 5 min, during which the number of abdominal writhes induced by the acetic acid was recorded. While intra-dPAG injection of 8-OHDPAT did not change open-arm antinociception (OAA), mCPP (0.01 nmol) enhanced it. Combined injections of ketanserin (10 nmol/0.1 μl), a 5-HT(2A/2C) receptor antagonist, and 0.01 nmol of mCPP (Experiment 3), selectively and completely blocked the OAA enhancement induced by mCPP. Although intra-dPAG injection of mCPP (0.01 nmol) also produced antinociception in EA-confined mice (Experiment 2), this effect was not confirmed in Experiment 3. Moreover, no other compound changed the nociceptive response in EA-confined animals. These results suggest that the 5-HT(2C) receptors located within the PAG play a role in this type of environmentally induced pain inhibition in mice.

  20. Pharmacogenetics of cytochrome P450 2B6 (CYP2B6): advances on polymorphisms, mechanisms, and clinical relevance

    PubMed Central

    Zanger, Ulrich M.; Klein, Kathrin

    2013-01-01

    Cytochrome P450 2B6 (CYP2B6) belongs to the minor drug metabolizing P450s in human liver. Expression is highly variable both between individuals and within individuals, owing to non-genetic factors, genetic polymorphisms, inducibility, and irreversible inhibition by many compounds. Drugs metabolized mainly by CYP2B6 include artemisinin, bupropion, cyclophosphamide, efavirenz, ketamine, and methadone. CYP2B6 is one of the most polymorphic CYP genes in humans and variants have been shown to affect transcriptional regulation, splicing, mRNA and protein expression, and catalytic activity. Some variants appear to affect several functional levels simultaneously, thus, combined in haplotypes, leading to complex interactions between substrate-dependent and -independent mechanisms. The most common functionally deficient allele is CYP2B6*6 [Q172H, K262R], which occurs at frequencies of 15 to over 60% in different populations. The allele leads to lower expression in liver due to erroneous splicing. Recent investigations suggest that the amino acid changes contribute complex substrate-dependent effects at the activity level, although data from recombinant systems used by different researchers are not well in agreement with each other. Another important variant, CYP2B6*18 [I328T], occurs predominantly in Africans (4–12%) and does not express functional protein. A large number of uncharacterized variants are currently emerging from different ethnicities in the course of the 1000 Genomes Project. The CYP2B6 polymorphism is clinically relevant for HIV-infected patients treated with the reverse transcriptase inhibitor efavirenz, but it is increasingly being recognized for other drug substrates. This review summarizes recent advances on the functional and clinical significance of CYP2B6 and its genetic polymorphism, with particular emphasis on the comparison of kinetic data obtained with different substrates for variants expressed in different recombinant expression systems. PMID

  1. Antagonistic effects of extracts from Artemisia rupetris L. and Leontopodium leontopodioides to CC chemokine receptor 2b (CCR2b).

    PubMed

    Yu, Qin-Wei; Hu, Jie; Wang, Hao; Chen, Xin; Zhao, Fang; Gao, Peng; Yang, Qiu-Bin; Sun, Dan-Dan; Zhang, Lu-Yong; Yan, Ming

    2016-05-01

    The present study was designed to establish a suitable assay to explore CCR2b receptor antagonists from the natural products of Artemisia rupetris and Leontopodium leontopodioides. An aequorin assay was developed as a cell-based assay suitable for 384-well microplate and used for screening CCR2b receptor antagonists from natural products. Through establishing suitable conditions, the assay was shown to be suitable for screening of CCR2b receptor antagonists. Seven compounds were identified in preliminary screening. Five of them showed evident dose-response relationship in secondary screening. The structure-activity relationship study suggested that 7-position hydroxyl group of flavonoids was necessary, a polar group should be introduced on the 3-position, and the substituents on 2-position benzene ring of flavonoids have little influence on the potentency of the inhibition activity on CCR2b receptor. The ortho-position dihydroxyl structure in quinic acid compounds may be important. In conclusion, Compounds HR-1, 5, 7, and AR-20, 35 showed activity as antagonist of CCR2b receptor, which shed lights on the development of novel drugs as CCR2b receptor antagonists for preventing inflammation related diseases. PMID:27478099

  2. Serotonin 2B Receptor Antagonism Prevents Heritable Pulmonary Arterial Hypertension

    PubMed Central

    Schroer, Alison K.; Chen, Peter; Ryzhova, Larisa M.; Gladson, Santhi; Shay, Sheila; Hutcheson, Joshua D.; Merryman, W. David

    2016-01-01

    Serotonergic anorexigens are the primary pharmacologic risk factor associated with pulmonary arterial hypertension (PAH), and the resulting PAH is clinically indistinguishable from the heritable form of disease, associated with BMPR2 mutations. Both BMPR2 mutation and agonists to the serotonin receptor HTR2B have been shown to cause activation of SRC tyrosine kinase; conversely, antagonists to HTR2B inhibit SRC trafficking and downstream function. To test the hypothesis that a HTR2B antagonist can prevent BMRP2 mutation induced PAH by restricting aberrant SRC trafficking and downstream activity, we exposed BMPR2 mutant mice, which spontaneously develop PAH, to a HTR2B antagonist, SB204741, to block the SRC activation caused by BMPR2 mutation. SB204741 prevented the development of PAH in BMPR2 mutant mice, reduced recruitment of inflammatory cells to their lungs, and reduced muscularization of their blood vessels. By atomic force microscopy, we determined that BMPR2 mutant mice normally had a doubling of vessel stiffness, which was substantially normalized by HTR2B inhibition. SB204741 reduced SRC phosphorylation and downstream activity in BMPR2 mutant mice. Gene expression arrays indicate that the primary changes were in cytoskeletal and muscle contractility genes. These results were confirmed by gel contraction assays showing that HTR2B inhibition nearly normalizes the 400% increase in gel contraction normally seen in BMPR2 mutant smooth muscle cells. Heritable PAH results from increased SRC activation, cellular contraction, and vascular resistance, but antagonism of HTR2B prevents SRC phosphorylation, downstream activity, and PAH in BMPR2 mutant mice. PMID:26863209

  3. Lithium insertion in nanostructured TiO(2)(B) architectures.

    PubMed

    Dylla, Anthony G; Henkelman, Graeme; Stevenson, Keith J

    2013-05-21

    Electric vehicles and grid storage devices have potentialto become feasible alternatives to current technology, but only if scientists can develop energy storage materials that offer high capacity and high rate capabilities. Chemists have studied anatase, rutile, brookite and TiO2(B) (bronze) in both bulk and nanostructured forms as potential Li-ion battery anodes. In most cases, the specific capacity and rate of lithiation and delithiation increases as the materials are nanostructured. Scientists have explained these enhancements in terms of higher surface areas, shorter Li(+) diffusion paths and different surface energies for nanostructured materials allowing for more facile lithiation and delithiation. Of the most studied polymorphs, nanostructured TiO2(B) has the highest capacity with promising high rate capabilities. TiO2(B) is able to accommodate 1 Li(+) per Ti, giving a capacity of 335 mAh/g for nanotubular and nanoparticulate TiO2(B). The TiO2(B) polymorph, discovered in 1980 by Marchand and co-workers, has been the focus of many recent studies regarding high power and high capacity anode materials with potential applications for electric vehicles and grid storage. This is due to the material's stability over multiple cycles, safer lithiation potential relative to graphite, reasonable capacity, high rate capability, nontoxicity, and low cost (Bruce, P. G.; Scrosati, B.; Tarascon, J.-M. Nanomaterials for Rechargeable Lithium Batteries. Angew. Chem., Int. Ed.2008, 47, 2930-2946). One of the most interesting properties of TiO2(B) is that both bulk and nanostructured forms lithiate and delithiate through a surface redox or pseudocapacitive charging mechanism, giving rise to stable high rate charge/discharge capabilities in the case of nanostructured TiO2(B). When other polymorphs of TiO2 are nanostructured, they still mainly intercalate lithium through a bulk diffusion-controlled mechanism. TiO2(B) has a unique open crystal structure and low energy Li

  4. Trends and Variations of Ocean Surface Latent Heat Flux: Results from GSSTF2c Data Set

    NASA Technical Reports Server (NTRS)

    Gao, Si; Chiu, Long S.; Shie, Chung-Lin

    2013-01-01

    Trends and variations of Goddard Satellite-based Surface Turbulent Fluxes (GSSTF) version 2c (GSSTF2c) latent heat flux (LHF) are examined. This version of LHF takes account of the correction in Earth incidence angle. The trend of global mean LHF for GSSTF2c is much reduced relative to GSSTF version 2b Set 1 and Set 2 for the same period 1988-2008. Temporal increase of GSSTF2c LHF in the two decades is 11.0%, in which 3.1%, 5.8%, and 2.1% are attributed to the increase in wind, the increase in sea surface saturated air humidity, and the decrease in near-surface air humidity, respectively. The first empirical orthogonal function of LHF is a conventional El Nino Southern Oscillation (ENSO) mode. However, the trends in LHF are independent of conventional ENSO phenomena. After removing ENSO signal, the pattern of LHF trends is primarily determined by the pattern of air-sea humidity difference trends.

  5. AutoMOPS--B2B and B2C in mask making: mask manufacturing performance and customer satisfaction improvement through better information flow management

    NASA Astrophysics Data System (ADS)

    de Ridder, Luc; Filies, Olaf; Rodriguez, Ben; Kuijken, Aart

    2001-04-01

    Through application of modern supply chain concepts in combination with state-of-the-art information technology, mask manufacturing performance and customer satisfaction can be improved radically. The AutoMOPS solution emphasizes on the elimination of the order verification through paperless, electronically linked information sharing/exchange between chip design, mask production and prototype production stages.

  6. Flow Simulation of N2B Hybrid Wing Body Configuration

    NASA Technical Reports Server (NTRS)

    Kim, Hyoungjin; Liou, Meng-Sing

    2012-01-01

    The N2B hybrid wing body aircraft was conceptually designed to meet environmental and performance goals for the N+2 generation transport set by the subsonic fixed wing project. In this study, flow fields around the N2B configuration is simulated using a Reynolds-averaged Navier-Stokes flow solver using unstructured meshes. Boundary conditions at engine fan face and nozzle exhaust planes are provided by response surfaces of the NPSS thermodynamic engine cycle model. The present flow simulations reveal challenging design issues arising from boundary layer ingestion offset inlet and nacelle-airframe interference. The N2B configuration can be a good test bed for application of multidisciplinary design optimization technology.

  7. ORM-Based Semantics of B2B Transactions

    NASA Astrophysics Data System (ADS)

    Balsters, H.; van Blommestein, F.

    After widespread implementation of Enterprise Resource Planning and Personal Information Management, the next wave in the application of ICT is headed towards business to business (B2B) communication. B2B has a number of specific aspects, one of them being negotiation. This aspect has been largely neglected by present implementations of standard EDI- or XML-messaging and by B2B webservice implementations. In this paper a precise model is given of the negotiation process. The requirements of a potential Buyer and the offer of a potential Seller are matched and, if the negotiation is successful, a contract is concluded. The negotiation process model is represented in ORM, extended with dynamic constraints. Our model may be implemented in the databases of the trading partners and in message- or service definitions.

  8. Expanding Interprofessional EHR Data in i2b2

    PubMed Central

    Westra, Bonnie L.; Christie, Beverly; Johnson, Steven G.; Pruinelli, Lisiane; LaFlamme, Anne; Park, Jung In; Sherman, Suzan G.; Byrne, Matthew D.; Ranallo, Piper; Speedie, Stuart

    2016-01-01

    Emerging issues of team-based care, precision medicine, and big data science underscore the need for health information technology (HIT) tools for integrating complex data in consistent ways to achieve the triple aims of improving patient outcomes, patient experience, and cost reductions. The purpose of this study was to demonstrate the feasibility of creating a hierarchical flowsheet ontology in i2b2 using data-derived information models and determine the underlying informatics and technical issues. This study is the first of its kind to use information models that aggregate team-based care across time, disciplines, and settings into 14 information models that were integrated into i2b2 in a hierarchical model. In the process of successfully creating a hierarchical ontology for flowsheet data in i2b2, we uncovered a variety of informatics and technical issues described in this paper. PMID:27570680

  9. Expanding Interprofessional EHR Data in i2b2.

    PubMed

    Westra, Bonnie L; Christie, Beverly; Johnson, Steven G; Pruinelli, Lisiane; LaFlamme, Anne; Park, Jung In; Sherman, Suzan G; Byrne, Matthew D; Ranallo, Piper; Speedie, Stuart

    2016-01-01

    Emerging issues of team-based care, precision medicine, and big data science underscore the need for health information technology (HIT) tools for integrating complex data in consistent ways to achieve the triple aims of improving patient outcomes, patient experience, and cost reductions. The purpose of this study was to demonstrate the feasibility of creating a hierarchical flowsheet ontology in i2b2 using data-derived information models and determine the underlying informatics and technical issues. This study is the first of its kind to use information models that aggregate team-based care across time, disciplines, and settings into 14 information models that were integrated into i2b2 in a hierarchical model. In the process of successfully creating a hierarchical ontology for flowsheet data in i2b2, we uncovered a variety of informatics and technical issues described in this paper. PMID:27570680

  10. Substrate Recognition of Histone H2B by DUBm

    NASA Astrophysics Data System (ADS)

    Henderson, Elizabeth; Berndsen, Christopher; Wolberger, Cynthia

    2011-03-01

    The SAGA complex is a transcriptional coactivator that regulates gene expression in eukaryotes via histone acetylation and deubiquitination, which are crucial for transcription. Our lab is investigating the SAGA-dependent deubiquitination of histone H2B. The deubiquitinating module (DUBm) of SAGA is comprised of a ubiquitin-specific protease, Ubp8, and three other proteins. It is known that Ubp8 cleaves ubiquitin from histone H2B, however, the specific way in which the enzyme binds to the substrate remains elusive. In order to unravel this mechanism, we attempted to determine the crystal structure of the substrate binding complex. We obtained this substrate by exploiting the techniques of intein chemistry to artificially ubiquitinate a histone H2B peptide, which we then co-crystallized with DUBm. Additionally, we synthesized Ub-K63R-linked chains and Ub-K48-linked chains and co-crystallized them with DUBm.

  11. Discovery of Potent and Highly Selective A2B Adenosine Receptor Antagonist Chemotypes.

    PubMed

    El Maatougui, Abdelaziz; Azuaje, Jhonny; González-Gómez, Manuel; Miguez, Gabriel; Crespo, Abel; Carbajales, Carlos; Escalante, Luz; García-Mera, Xerardo; Gutiérrez-de-Terán, Hugo; Sotelo, Eddy

    2016-03-10

    Three novel families of A2B adenosine receptor antagonists were identified in the context of the structural exploration of the 3,4-dihydropyrimidin-2(1H)-one chemotype. The most appealing series contain imidazole, 1,2,4-triazole, or benzimidazole rings fused to the 2,3-positions of the parent diazinone core. The optimization process enabled identification of a highly potent (3.49 nM) A2B ligand that exhibits complete selectivity toward A1, A2A, and A3 receptors. The results of functional cAMP experiments confirmed the antagonistic behavior of representative ligands. The main SAR trends identified within the series were substantiated by a molecular modeling study based on a receptor-driven docking model constructed on the basis of the crystal structure of the human A2A receptor.

  12. Importance of the GluN2B carboxy-terminal domain for enhancement of social memories

    PubMed Central

    Jacobs, Stephanie; Wei, Wei; Wang, Deheng

    2015-01-01

    The N-methyl-D-aspartate (NMDA) receptor is known to be necessary for many forms of learning and memory, including social recognition memory. Additionally, the GluN2 subunits are known to modulate multiple forms of memory, with a high GluN2A:GluN2B ratio leading to impairments in long-term memory, while a low GluN2A:GluN2B ratio enhances some forms of long-term memory. Here, we investigate the molecular motif responsible for the differences in social recognition memory and olfactory memory in the forebrain-specific transgenic GluN2A overexpression mice and the forebrain-specific transgenic GluN2B overexpression mice by using two transgenic mouse lines that overexpress chimeric GluN2 subunits. The transgenic chimeric GluN2 subunit mice were tested for their ability to learn and remember fruit scents, male juveniles of the same strain, females of the same strain, male juveniles of another strain, and rodents of another species. The data presented here demonstrate that the GluN2B carboxy-terminal domain is necessary for enhanced social recognition memory in GluN2B transgenic overexpression mice. Furthermore, the GluN2A carboxy-terminal domain is responsible for the impaired long-term olfactory and social memory observed in the GluN2A overexpression mice. PMID:26179233

  13. DNA encoding an. alpha. sub 2B -adrenergic receptor

    SciTech Connect

    Weinshank, R.L.; Hartig, P.R.

    1991-10-01

    This paper describes an isolated nucleic acid molecule encoding a human alpha 2B-adrenergic receptor. This patent also describes an isolated nucleic acid molecule, wherein the isolated nucleic acid molecule is a DNA molecule and a mammalian cell comprising the DNA molecule.

  14. Further Advances in Optimizing (2-Phenylcyclopropyl)methylamines as Novel Serotonin 2C Agonists: Effects on Hyperlocomotion, Prepulse Inhibition, and Cognition Models.

    PubMed

    Cheng, Jianjun; Giguere, Patrick M; Schmerberg, Claire M; Pogorelov, Vladimir M; Rodriguiz, Ramona M; Huang, Xi-Ping; Zhu, Hu; McCorvy, John D; Wetsel, William C; Roth, Bryan L; Kozikowski, Alan P

    2016-01-28

    A series of novel compounds with two halogen substituents have been designed and synthesized to further optimize the 2-phenylcyclopropylmethylamine scaffold in the quest for drug-like 5-HT2C agonists. Compound (+)-22a was identified as a potent 5-HT2C receptor agonist, with good selectivity against the 5-HT2B and the 5-HT2A receptors. ADMET assays showed that compound (+)-22a possessed desirable properties in terms of its microsomal stability, and CYP and hERG inhibition, along with an excellent brain penetration profile. Evaluation of (+)-22a in animal models of schizophrenia-related behaviors revealed that it had a desirable activity profile, as it reduced d-amphetamine-stimulated hyperlocomotion in the open field test, it restored d-amphetamine-disrupted prepulse inhibition, it induced cognitive improvements in the novel object recognition memory test in NR1-KD animals, and it produced very little catalepsy relative to haloperidol. These data support the further development of (+)-22a as a drug candidate for the treatment of schizophrenia. PMID:26704965

  15. Structural transformations of Li2C2 at high pressures

    NASA Astrophysics Data System (ADS)

    Efthimiopoulos, Ilias; Benson, Daryn E.; Konar, Sumit; Nylén, Johanna; Svensson, Gunnar; Häussermann, Ulrich; Liebig, Stefan; Ruschewitz, Uwe; Vazhenin, Grigory V.; Loa, Ingo; Hanfland, Michael; Syassen, Karl

    2015-08-01

    Structural changes of Li2C2 under pressure were studied by synchrotron x-ray diffraction in a diamond anvil cell under hydrostatic conditions and by using evolutionary search methodology for crystal structure prediction. We show that the high-pressure polymorph of Li2C2 , which forms from the I m m m ground-state structure (Z =2 ) at around 15 GPa, adopts an orthorhombic P n m a structure with Z =4 . Acetylide C2 dumbbells characteristic of I m m m Li2C2 are retained in P n m a Li2C2 . The structure of P n m a Li2C2 relates closely to the anticotunnite-type structure. C2 dumbbell units are coordinated by nine Li atoms, as compared to eight in the antifluorite structure of I m m m Li2C2 . First-principles calculations predict a transition of P n m a Li2C2 at 32 GPa to a topologically identical phase with a higher C m c m symmetry. The coordination of C2 dumbbell units by Li atoms is increased to 11. The structure of C m c m Li2C2 relates closely to the Ni2 In-type structure. It is calculated that C m c m Li2C2 becomes metallic at pressures above 40 GPa. In experiments, however, P n m a Li2C2 is susceptible to irreversible amorphization.

  16. Photoelectron spectroscopy of the hydroxymethoxide anion, H2C(OH)O-

    NASA Astrophysics Data System (ADS)

    Oliveira, Allan M.; Lehman, Julia H.; McCoy, Anne B.; Lineberger, W. Carl

    2016-09-01

    We report the negative ion photoelectron spectroscopy of the hydroxymethoxide anion, H2C(OH)O-. The photoelectron spectra show that 3.49 eV photodetachment produces two distinct electronic states of the neutral hydroxymethoxy radical (H2C(OH)Oṡ). The H2C(OH)Oṡ ground state (X ˜ 2A) photoelectron spectrum exhibits a vibrational progression consisting primarily of the OCO symmetric and asymmetric stretches, the OCO bend, as well as combination bands involving these modes with other, lower frequency modes. A high-resolution photoelectron spectrum aids in the assignment of several vibrational frequencies of the neutral H2C(OH)Oṡ radical, including an experimental determination of the H2C(OH)Oṡ 2ν12 overtone of the H-OCO torsional vibration as 220(10) cm-1. The electron affinity of H2C(OH)Oṡ is determined to be 2.220(2) eV. The low-lying A ˜ 2A excited state is also observed, with a spectrum that peaks ˜0.8 eV above the X ˜ 2A state origin. The A ˜ 2A state photoelectron spectrum is a broad, partially resolved band. Quantum chemical calculations and photoelectron simulations aid in the interpretation of the photoelectron spectra. In addition, the gas phase acidity of methanediol is calculated to be 366(2) kcal mol-1, which results in an OH bond dissociation energy, D0(H2C(OH)O-H), of 104(2) kcal mol-1, using the experimentally determined electron affinity of the hydroxymethoxy radical.

  17. Effects of chronic NMDA-NR2b inhibition in the median eminence of the reproductive senescent female rat.

    PubMed

    Kermath, B A; Riha, P D; Sajjad, A; Gore, A C

    2013-10-01

    Gonadotrophin-releasing hormone (GnRH) neurones of the hypothalamic-pituitary-gonadal (HPG) axis drive reproductive function and undergo age-related decreases in activation during the transition to reproductive senescence. Decreased GnRH secretion from the median eminence (ME) partially arises from attenuated glutamatergic signalling via the NMDA receptor (NMDAR) and may be a result of changing NMDAR stoichiometry to favour NR2b over NR2a subunit expression with ageing. We have previously shown that the systemic inhibition of NR2b-containing receptors with ifenprodil, an NR2b-specific antagonist, stimulates parameters of luteinising hormone (used as a proxy for GnRH) release in both young and middle-aged females. In the present study, we chronically administered ifenprodil, an NR2b-specific antagonist, at the site of GnRH terminals in the ME or at GnRH perikarya in the preoptic area, in reproductively senescent middle-aged female rats, aiming to determine whether NR2b antagonism could restore aspects of reproductive functionality. Effects on oestrous cyclicity, serum hormones, and protein expression of GnRH, NR2b and phosphorylated NR2b (Tyr-1472) in the ME were measured. Chronic ifenprodil treatment in the ME (but not the preoptic area) altered oestrous cyclicity by increasing the percentage of days spent in pro-oestrus. This was accompanied by increased GnRH fluorescence intensity in the external ME zone and a greater proportion of GnRH terminals that co-labelled with pNR2b with treatment. We also observed changes in the relationships between protein immunofluorescence, serum hormone levels and other aspects of reproductive physiology in acyclic females, as revealed by bionetwork analysis. Together, these data support the hypothesis that NMDAR-NR2b expression and phosphorylation state play a role in reproductive senescence and highlight the ME as a major player in reproductive ageing.

  18. Distribution of galanin receptor 2b neurons and interaction with galanin in the zebrafish central nervous system.

    PubMed

    Kim, Eunmi; Jeong, Inyoung; Kim, Suhyun; Kim, Hwan-Ki; Lee, Dong-Won; Kim, Boa; Seong, Jae Young; Bae, Young-Ki; Ryu, Jae-Ho; Park, Hae-Chul

    2016-08-15

    Galanin is a multifunctional neuropeptide that is implicated in the modulation of physiological processes, including nociception, cognition, feeding behavior, neuronal growth, and reproduction. The physiological effects of galanin are mediated through its interaction with three different G protein-coupled receptors, i.e., GALR1, GALR2, and GALR3. Unlike mammals, zebrafish have four different receptors for galanin, diversified from GALR1 (GAL1a and GALR1b) and GALR2 (GALR2a and GALR2b). Despite the importance of galanin in the central nervous system (CNS), no information has been reported regarding GalR2 in zebrafish CNS. In this study, we found that galr2a is expressed at low levels in restricted areas of the brain; however, galr2b was widely expressed in CNS including olfactory bulb, midbrain tegmentum, preoptic region, dorsal thalamus, posterior tuberculum, postoptic commissure, hindbrain, and spinal cord. To further analyze the distribution of GALR2b neurons and their interaction with GAL, we generated Tg(galr2b:egfp) zebrafish, which express enhanced green fluorescent protein (EGFP) under the control of a galr2b promoter. Investigation of the CNS of transgenic reporter zebrafish revealed that galr2b:EGFP(+) neurons are distributed and interact with galanin-immunoreactive (galanin-IR) cells in various regions of the brain and spinal cord. We found that in some regions of the brain and spinal cord, galanin-IR nerve cells were not observed near galr2b:EGFP neurons, suggesting that GALR2b may have the potential to interact with other ligands instead of galanin in these regions.

  19. A role for Sv2c in basal ganglia functions.

    PubMed

    Dardou, D; Monlezun, S; Foerch, P; Courade, J P; Cuvelier, L; De Ryck, M; Schiffmann, S N

    2013-04-24

    SV2C is an isoform of the synaptic vesicle 2 protein family that exhibits a particular pattern of brain expression with enriched expression in several basal ganglia nuclei. In the present study, we have investigated SV2C implication in both normal and pathological basal ganglia functioning with a peculiar attention to dopamine neuron containing regions. In SV2C-/- mice, the expression of tyrosine hydroxylase mRNA in midbrain dopaminergic neurons was largely and significantly increased and enkephalin mRNA expression was significantly decreased in the caudate-putamen and accumbens nucleus. The expression of SV2C was studied in two models of dopaminergic denervation (6-OHDA- and MPTP-induced lesions). In dopamine-depleted animals, SV2C mRNA expression was significant increased in the striatum. In order to further understand the role of SV2C, we performed behavioral experiments on SV2C-/- mice and on knock-down mice receiving an injection of adeno-associated virus expressing SV2C miRNA specifically in the ventral midbrain. These modifications of SV2C expression had little or no impact on behavior in open field and elevated plus maze. However, even if complete loss of SV2C had no impact on conditioned place preference induced by cocaine, the specific knock-down of SV2C expression in the dopaminergic neurons completely abolished the development of a CPP while the reaction to an acute drug injection remains similar in these mice compared to control mice. These results showed that SV2C, a poorly functionally characterized protein is strongly involved in normal operation of the basal ganglia network and could be also involved in system adaptation in basal ganglia pathological conditions. PMID:23458503

  20. Unusual behaviour of (Np,Pu)B2C

    NASA Astrophysics Data System (ADS)

    Klimczuk, Tomasz; Boulet, Pascal; Griveau, Jean-Christophe; Colineau, Eric; Bauer, Ernst; Falmbigl, Matthias; Rogl, Peter; Wastin, Franck

    2015-02-01

    Two transuranium metal boron carbides, NpB2C and PuB2C have been synthesized by argon arc melting. The crystal structures of the {Np,Pu}B2C compounds were determined from single-crystal X-ray data to be isotypic with the ThB2C-type (space group ?, a = 0.6532(2) nm; c = 1.0769(3) nm for NpB2C and a = 0.6509(2) nm; c = 1.0818(3) nm for PuB2C; Z = 9). Physical properties have been derived from polycrystalline bulk material in the temperature range from 2 to 300 K and in magnetic fields up to 9 T. Magnetic susceptibility and heat capacity data indicate the occurrence of antiferromagnetic ordering for NpB2C with a Neel temperature TN = 68 K. PuB2C is a Pauli paramagnet most likely due to a strong hybridization of s(p,d) electrons with the Pu-5f states. A pseudo-gap, as concluded from the Sommerfeld value and the electronic transport, is thought to be a consequence of the hybridization. The magnetic behaviour of {Np,Pu}B2C is consistent with the criterion of Hill.

  1. D1((2)B2g) to D0((2)Au) Fluorescence from the Matrix-Isolated Perylene Cation Following Laser Excitation into the D5(2)B3g) and D2 ((2)B3g) Electronic States

    NASA Technical Reports Server (NTRS)

    Chillier, Xavier D. F.; Stone, Bradley M.; Joblin, Christine; Salama, Farid; Allamandola, Louis J.; DeVincenzi, Donald L. (Technical Monitor)

    2001-01-01

    Fluorescence spectra of the perylene cation, pumped by direct laser excitation via the D(sub 2)((2)B(sub 3g)) (left arrow) D(sub 0)((2)A(sub u)) and D(sub 5)(2)B(sub 3g)) (left arrow) D(sub 0)((2)A(sub u)) transitions, are presented. Direct excitation into the D5 or D2 states is followed by rapid non-radiative relaxation to D1 that, in turn,relaxes radiatively. Excitation spectroscopy across the D(sub 2)((2)B(sub 3g)) (left arrow) D(sub 0)((2)A(sub u)) transition near 730 nm shows that site splitting plays little or no role in determining the spectral substructure in the ion spectra. Tentative assignments for ground state vibrational frequencies are made by comparison of spectral intervals with calculated normal mode frequencies.

  2. Evolution of seismic layer 2B across the Juan de Fuca Ridge from hydrophone streamer 2-D traveltime tomography

    NASA Astrophysics Data System (ADS)

    Newman, Kori R.; Nedimović, Mladen R.; Canales, J. Pablo; Carbotte, Suzanne M.

    2011-05-01

    How oceanic crust evolves has important implications for understanding both subduction earthquake hazards and energy and mass exchange between the Earth's interior and the oceans. Although considerable work has been done characterizing the evolution of seismic layer 2A, there has been little analysis of the processes that affect layer 2B after formation. Here we present high-resolution 2-D tomographic models of seismic layer 2B along ˜300 km long multichannel seismic transects crossing the Endeavour, Northern Symmetric, and Cleft segments of the Juan de Fuca Ridge. These models show that seismic layer 2B evolves rapidly following a different course than layer 2A. The upper layer 2B velocities increase on average by 0.8 km/s and reach a generally constant velocity of 5.2 ± 0.3 km/s within the first 0.5 Myr after crustal formation. This suggests that the strongest impact on layer 2B evolution may be that of mineral precipitation due to "active" hydrothermal circulation centered about the ridge crest and driven by the heat from the axial magma chamber. Variations in upper layer 2B velocity with age at time scales ≥0.5 Ma show correlation about the ridge axis indicating that in the long term, crustal accretion processes affect both sides of the ridge axis in a similar way. Below the 0.5 Ma threshold, differences in 2B velocity are likely imprinted during crustal formation or early crustal evolution. Layer 2B velocities at propagator wakes (5.0 ± 0.2 km/s), where enhanced faulting and cracking are expected, and at areas that coincide with extensional or transtensional faulting are on average slightly slower than in normal mature upper layer 2B. Analysis of the layer 2B velocities from areas where the hydrothermal patterns are known shows that the locations of current and paleohydrothermal discharge and recharge zones are marked by reduced and increased upper layer 2B velocities, respectively. Additionally, the distance between present up-flow and down-flow zones is

  3. "IARC group 2B Carcinogens" reported in cigarette mainstream smoke.

    PubMed

    Smith, C J; Perfetti, T A; Mullens, M A; Rodgman, A; Doolittle, D J

    2000-09-01

    In the third and final part of a series surveying the international literature on the "IARC carcinogens" in cigarette mainstream smoke, the "IARC Group 2B carcinogens" are reviewed. A search of the published literature shows that of 227 chemical components classified as Group 2B, that is, "possible carcinogens," by the International Agency for Research on Cancer (IARC), 48 have previously been reported in cigarette mainstream smoke. Owing to its highly interactive molecular nature, removal from or inhibition of a given mutagenic or carcinogenic chemical within the complex aerosol mixture cannot reliably be predicted to reduce either the overall mutagenicity or carcinogenicity. However, in the absence of experimental data demonstrating an increase in adverse biological activity resulting from removal or inhibition of a potentially carcinogenic constituent, negation of the activity of the potential carcinogen may be considered as a desirable circumstance.

  4. Structural stability of W2B5 under high pressure

    NASA Astrophysics Data System (ADS)

    Kumar, N. R. Sanjay; Shekar, N. V. Chandra; Sahu, P. Ch.

    2015-05-01

    High-pressure structural stability studies have been carried out on tungsten boride W2B5 up to maximum pressure of 36 GPa using a Mao-Bell diamond-anvil cell at beamline BR-12 of the ELETTRA synchrotron facility (λ = 0.68881 Å). The hexagonal phase (S.G:P63/mmc) of W2B5 is stable up to the maximum pressure studied. The bulk modulus is estimated to be ~347 GPa using the Birch-Murnaghan equation of state. The variation of lattice parameters and bond lengths B-B and W-B have been studied and the c-axis is seen to be marginally more compressible than the a-axis.

  5. Chemical Reactivity Perspective into the Group 2B Metals Halides.

    PubMed

    Özen, Alimet Sema; Akdeniz, Zehra

    2016-06-30

    Chemical reactivity descriptors within the conceptual density functional theory can be used to understand the nature of the interactions between two monomers of the Group 2B metal halides. This information might be valuable in the development of adequate force law parameters for simulations in the liquid state. In this study, MX2 monomers and dimers, where M = Zn, Cd, Hg and X = F, Cl, Br, I, were investigated in terms of chemical reactivity descriptors. Relativistic effects were taken into account using the effective core potential (ECP) approach. Correlations were produced between global and local reactivity descriptors and dimerization energies. Results presented in this work represent the first systematic investigation of Group 2B metal halides in the literature from a combined point of view of both relativistic effects and chemical reactivity descriptors. Steric effects were found to be responsible for the deviation from the chemical reactivity principles. They were introduced into the chemical reactivity descriptors such as local softness.

  6. Alanine Expansions Associated with Congenital Central Hypoventilation Syndrome Impair PHOX2B Homeodomain-mediated Dimerization and Nuclear Import*

    PubMed Central

    Di Lascio, Simona; Belperio, Debora

    2016-01-01

    Heterozygous mutations of the human PHOX2B gene, a key regulator of autonomic nervous system development, lead to congenital central hypoventilation syndrome (CCHS), a neurodevelopmental disorder characterized by a failure in the autonomic control of breathing. Polyalanine expansions in the 20-residues region of the C terminus of PHOX2B are the major mutations responsible for CCHS. Elongation of the alanine stretch in PHOX2B leads to a protein with altered DNA binding, transcriptional activity, and nuclear localization and the possible formation of cytoplasmic aggregates; furthermore, the findings of various studies support the idea that CCHS is not due to a pure loss of function mechanism but also involves a dominant negative effect and/or toxic gain of function for PHOX2B mutations. Because PHOX2B forms homodimers and heterodimers with its paralogue PHOX2A in vitro, we tested the hypothesis that the dominant negative effects of the mutated proteins are due to non-functional interactions with the wild-type protein or PHOX2A using a co-immunoprecipitation assay and the mammalian two-hybrid system. Our findings show that PHOX2B forms homodimers and heterodimerizes weakly with mutated proteins, exclude the direct involvement of the polyalanine tract in dimer formation, and indicate that mutated proteins retain partial ability to form heterodimers with PHOX2A. Moreover, in this study, we investigated the effects of the longest polyalanine expansions on the homeodomain-mediated nuclear import, and our data clearly show that the expanded C terminus interferes with this process. These results provide novel insights into the effects of the alanine tract expansion on PHOX2B folding and activity. PMID:27129232

  7. Agent-based services for B2B electronic commerce

    NASA Astrophysics Data System (ADS)

    Fong, Elizabeth; Ivezic, Nenad; Rhodes, Tom; Peng, Yun

    2000-12-01

    The potential of agent-based systems has not been realized yet, in part, because of the lack of understanding of how the agent technology supports industrial needs and emerging standards. The area of business-to-business electronic commerce (b2b e-commerce) is one of the most rapidly developing sectors of industry with huge impact on manufacturing practices. In this paper, we investigate the current state of agent technology and the feasibility of applying agent-based computing to b2b e-commerce in the circuit board manufacturing sector. We identify critical tasks and opportunities in the b2b e-commerce area where agent-based services can best be deployed. We describe an implemented agent-based prototype system to facilitate the bidding process for printed circuit board manufacturing and assembly. These activities are taking place within the Internet Commerce for Manufacturing (ICM) project, the NIST- sponsored project working with industry to create an environment where small manufacturers of mechanical and electronic components may participate competitively in virtual enterprises that manufacture printed circuit assemblies.

  8. Structural, electronic and bonding properties of antifluorite crystals of Be2C, BeMgC and Mg2C

    NASA Astrophysics Data System (ADS)

    Joshi, K. B.; Trivedi, D. K.; Paliwal, U.; Galav, K. L.

    2016-05-01

    Structure prediction methods are coupled with the first-principles linear combination of atomic orbitals method to propose the crystal parameters and bulk modulus of antifluorite BeMgC. The binary antifluorite methanides Be2C, Mg2C are also studied. Electronic structure calculations and Mulliken population analyses (MPA) are performed to unravel bands dispersion and bonding properties. The values of the indirect band gap Γ → X for Be2C, Mg2C and BeMgC, in order, are 2.90, 2.05 and 1.86 eV. The calculated energies of a few occupied bands in Be2C are in very good agreement with the available experimental data. The application of pressure causes change in the band gap of three carbides. The Γ-Γ, Γ-X and Γ-K band gaps exhibit different trends with pressure. Effective charges on the basis of MPA in the three compounds are {(B{e}+1.095)}2{C}-2.19, {(M{g}+1.615)}2{C}-3.23 and B{e}+1.12M{g}+1.682{C}-2.802. It signifies covalent bonding in Be2C, ionic in Mg2C, and intermediate in the BeMgC.

  9. Structural, mechanical, and electronic properties of Rh2B and RhB2: first-principles calculations

    PubMed Central

    Chu, Binhua; Li, Da; Tian, Fubo; Duan, Defang; Sha, Xiaojing; Lv, Yunzhou; Zhang, Huadi; Liu, Bingbing; Cui, Tian

    2015-01-01

    The crystal structures of Rh2B and RhB2 at ambient pressure were explored by using the evolutionary methodology. A monoclinic P21/m structure of Rh2B was predicted and donated as Rh2B-I, which is energetically much superior to the previously experimentally proposed Pnma structure. At the pressure of about 39 GPa, the P21/m phase of Rh2B transforms to the C2/m phases. For RhB2, a new monoclinic P21/m phase was predicted, named as RhB2-II, it has the same structure type with Rh2B. Rh2B-I and RhB2-II are both mechanically and dynamically stable. They are potential low compressible materials. The analysis of electronic density of states and chemical bonding indicates that the formation of strong and directional covalent B-B and Rh-B bonds in these compounds contribute greatly to their stabilities and high incompressibility. PMID:26123399

  10. GluN2B-Containing NMDA Receptors Regulate AMPA Receptor Traffic through Anchoring of the Synaptic Proteasome.

    PubMed

    Ferreira, Joana S; Schmidt, Jeannette; Rio, Pedro; Águas, Rodolfo; Rooyakkers, Amanda; Li, Ka Wan; Smit, August B; Craig, Ann Marie; Carvalho, Ana Luisa

    2015-06-01

    NMDA receptors play a central role in shaping the strength of synaptic connections throughout development and in mediating synaptic plasticity mechanisms that underlie some forms of learning and memory formation in the CNS. In the hippocampus and the neocortex, GluN1 is combined primarily with GluN2A and GluN2B, which are differentially expressed during development and confer distinct molecular and physiological properties to NMDA receptors. The contribution of each subunit to the synaptic traffic of NMDA receptors and therefore to their role during development and in synaptic plasticity is still controversial. We report a critical role for the GluN2B subunit in regulating NMDA receptor synaptic targeting. In the absence of GluN2B, the synaptic levels of AMPA receptors are increased and accompanied by decreased constitutive endocytosis of GluA1-AMPA receptor. We used quantitative proteomic analysis to identify changes in the composition of postsynaptic densities from GluN2B(-/-) mouse primary neuronal cultures and found altered levels of several ubiquitin proteasome system components, in particular decreased levels of proteasome subunits. Enhancing the proteasome activity with a novel proteasome activator restored the synaptic levels of AMPA receptors in GluN2B(-/-) neurons and their endocytosis, revealing that GluN2B-mediated anchoring of the synaptic proteasome is responsible for fine tuning AMPA receptor synaptic levels under basal conditions.

  11. The ISS 2B PVTCS Ammonia Leak: An Operational History

    NASA Technical Reports Server (NTRS)

    Vareha, Anthony

    2014-01-01

    In 2006, the Photovoltaic Thermal Control System (PVTCS) for the International Space Station's 2B power channel began leaking ammonia at a rate of approximately 1.5lbm/year (out of a starting approximately 53lbm system ammonia mass). Initially, the operations strategy was "feed the leak," a strategy successfully put into action via Extra Vehicular Activity during the STS-134 mission. During this mission the system was topped off with ammonia piped over from a separate thermal control system. This recharge was to have allowed for continued power channel operation into 2014 or 2015, at which point another EVA would have been required. Without these periodic EVAs to refill the 2B coolant system, the channel would eventually leak enough fluid as to risk pump cavitation and system failure, resulting in the loss of the 2B power channel - the most critical of the Space Station's 8 power channels. In mid-2012, the leak rate increased to approximately 5lbm/year. Once discovered, an EVA was planned and executed within a 5 week timeframe to drastically alter the architecture of the PVTCS via connection to a dormant thermal control system not intended to be utilized as anything other than spare components. The purpose of this rerouting of the TCS was to increase system volume and to isolate the photovoltaic radiator, thought to be the likely leak source. This EVA was successfully executed on November 1st, 2012 and left the 2B PVTCS in a configuration where the system was now being adequately cooled via a totally different radiator than what the system was designed to utilize. Unfortunately, data monitoring over the next several months showed that the isolated radiator was not leaking, and the system itself continued to leak steadily until May 9th, 2013. It was on this day that the ISS crew noticed the visible presence of ammonia crystals escaping from the 2B channel's truss segment, signifying a rapid acceleration of the leak from 5lbm/year to 5lbm/day. Within 48 hours of the

  12. Oral application of freeze-dried yeast particles expressing the PCV2b Cap protein on their surface induce protection to subsequent PCV2b challenge in vivo.

    PubMed

    Patterson, Robert; Eley, Thomas; Browne, Christopher; Martineau, Henny M; Werling, Dirk

    2015-11-17

    Porcine circovirus type 2 (PCV2) is now endemic in every major pig producing country, causing PCV-associated disease (PCVAD), linked with large scale economic losses. Current vaccination strategies are based on the capsid protein of the virus and are reasonably successful in preventing PCVAD but fail to induce sterile immunity. Additionally, vaccinating whole herds is expensive and time consuming. In the present study a "proof of concept" vaccine trial was employed to test the effectiveness of powdered freeze-dried recombinant Saccharomyces cerevisiae yeast stably expressing the capsid protein of PCV2b on its surface as an orally applied vaccine. PCV2-free pigs were given 3 doses of vaccine or left un-vaccinated before challenge with a defined PCV2b strain. Rectal temperatures were measured and serum and faeces samples were collected weekly. At the end of the study, pigs were euthanized, tissue samples taken and tested for PCV2b load by qPCR and immunohistochemistry. The peak of viraemia in sera and faeces of unvaccinated pigs was higher than that of vaccinated pigs. Additionally more sIgA was found in faeces of vaccinated pigs than unvaccinated. Vaccination was associated with lower serum concentrations of TNFα and IL-1β but higher concentrations of IFNα and IFNγ in comparison to the unvaccinated animals. At the end of the trial, a higher viral load was found in several lymphatic tissues and the ileum of unvaccinated pigs in comparison to vaccinated pigs. The difference between groups was especially apparent in the ileum. The results presented here demonstrate a possible use for recombinant S. cerevisiae expressing viral proteins as an oral vaccine against PCV2. A powdered freeze-dried recombinant S. cerevisiae used as an oral vaccine could be mixed with feed and may offer a cheap and less labour intensive alternative to inoculation with the additional advantage that no cooling chain would be required for vaccine transport and storage. PMID:26476879

  13. Oral application of freeze-dried yeast particles expressing the PCV2b Cap protein on their surface induce protection to subsequent PCV2b challenge in vivo.

    PubMed

    Patterson, Robert; Eley, Thomas; Browne, Christopher; Martineau, Henny M; Werling, Dirk

    2015-11-17

    Porcine circovirus type 2 (PCV2) is now endemic in every major pig producing country, causing PCV-associated disease (PCVAD), linked with large scale economic losses. Current vaccination strategies are based on the capsid protein of the virus and are reasonably successful in preventing PCVAD but fail to induce sterile immunity. Additionally, vaccinating whole herds is expensive and time consuming. In the present study a "proof of concept" vaccine trial was employed to test the effectiveness of powdered freeze-dried recombinant Saccharomyces cerevisiae yeast stably expressing the capsid protein of PCV2b on its surface as an orally applied vaccine. PCV2-free pigs were given 3 doses of vaccine or left un-vaccinated before challenge with a defined PCV2b strain. Rectal temperatures were measured and serum and faeces samples were collected weekly. At the end of the study, pigs were euthanized, tissue samples taken and tested for PCV2b load by qPCR and immunohistochemistry. The peak of viraemia in sera and faeces of unvaccinated pigs was higher than that of vaccinated pigs. Additionally more sIgA was found in faeces of vaccinated pigs than unvaccinated. Vaccination was associated with lower serum concentrations of TNFα and IL-1β but higher concentrations of IFNα and IFNγ in comparison to the unvaccinated animals. At the end of the trial, a higher viral load was found in several lymphatic tissues and the ileum of unvaccinated pigs in comparison to vaccinated pigs. The difference between groups was especially apparent in the ileum. The results presented here demonstrate a possible use for recombinant S. cerevisiae expressing viral proteins as an oral vaccine against PCV2. A powdered freeze-dried recombinant S. cerevisiae used as an oral vaccine could be mixed with feed and may offer a cheap and less labour intensive alternative to inoculation with the additional advantage that no cooling chain would be required for vaccine transport and storage.

  14. Oral application of freeze-dried yeast particles expressing the PCV2b Cap protein on their surface induce protection to subsequent PCV2b challenge in vivo

    PubMed Central

    Patterson, Robert; Eley, Thomas; Browne, Christopher; Martineau, Henny M.; Werling, Dirk

    2015-01-01

    Porcine circovirus type 2 (PCV2) is now endemic in every major pig producing country, causing PCV-associated disease (PCVAD), linked with large scale economic losses. Current vaccination strategies are based on the capsid protein of the virus and are reasonably successful in preventing PCVAD but fail to induce sterile immunity. Additionally, vaccinating whole herds is expensive and time consuming. In the present study a “proof of concept” vaccine trial was employed to test the effectiveness of powdered freeze-dried recombinant Saccharomyces cerevisiae yeast stably expressing the capsid protein of PCV2b on its surface as an orally applied vaccine. PCV2-free pigs were given 3 doses of vaccine or left un-vaccinated before challenge with a defined PCV2b strain. Rectal temperatures were measured and serum and faeces samples were collected weekly. At the end of the study, pigs were euthanized, tissue samples taken and tested for PCV2b load by qPCR and immunohistochemistry. The peak of viraemia in sera and faeces of unvaccinated pigs was higher than that of vaccinated pigs. Additionally more sIgA was found in faeces of vaccinated pigs than unvaccinated. Vaccination was associated with lower serum concentrations of TNFα and IL-1β but higher concentrations of IFNα and IFNγ in comparison to the unvaccinated animals. At the end of the trial, a higher viral load was found in several lymphatic tissues and the ileum of unvaccinated pigs in comparison to vaccinated pigs. The difference between groups was especially apparent in the ileum. The results presented here demonstrate a possible use for recombinant S. cerevisiae expressing viral proteins as an oral vaccine against PCV2. A powdered freeze-dried recombinant S. cerevisiae used as an oral vaccine could be mixed with feed and may offer a cheap and less labour intensive alternative to inoculation with the additional advantage that no cooling chain would be required for vaccine transport and storage. PMID:26476879

  15. Genetic polymorphisms and phenotypic analysis of drug-metabolizing enzyme CYP2C19 in a Li Chinese population.

    PubMed

    Ding, Yipeng; Xu, Dongchuan; Zhang, Xiyang; Yang, Hua; Geng, Tingting; He, Ping; Yao, Jinjian; Yi, Shengyang; Xu, Heping; Wu, Duoyi; Wang, Xiang; Jin, Tianbo

    2015-01-01

    CYP2C19 is a highly polymorphic gene and CYP2C19 enzyme results in broad inter-individual variability in response to certain clinical drugs, while little is known about the genetic variation of CYP2C19 in Li Chinese population. The aim of this study was to identify different CYP2C19 mutant alleles and determine their frequencies, along with genotype frequencies, in the Li Chinese population. We used DNA sequencing to investigate promoter, exons, introns, and 3'UTR of the CYP2C19 gene in 100 unrelated healthy Li individuals from Hainan Province, China. We also used SIFT and PolyPhen-2 to predict the protein function of the non-synonymous mutation in CYP2C19 coding regions. We identified 22 different CYP2C19 polymorphisms in the Li Chinese population, including three novel variants (-254A > G, 17807T > C and 58025C > T). The allele frequencies of CYP2C19*1A, *1B, *2A and *3A were 50%, 24%, 24.5%, and 1.5%, respectively. The most common genotype combinations were *1A/*1B (48%) and *1A/*2A (49%). Additionally, the mutation Ala161Pro was predicted to be intolerant and possibly damaging by SIFT and PolyPhen-2, respectively. Our results shed new light on CYP2C19 polymorphisms in Li individuals, which may help to optimize pharmacotherapy effectiveness by providing personalized medicine to this ethnic group.

  16. Anisotropic elastic and vibrational properties of Ru2B3 and Os2B3: a first-principles investigation

    NASA Astrophysics Data System (ADS)

    Ozisik, Haci; Deligoz, Engin; Surucu, Gokhan; Bogaz Ozisik, Havva

    2016-07-01

    The structural, mechanical and lattice dynamical properties of Ru2B3 and Os2B3 have been investigated by using a first-principles method based on the density functional theory within the generalized gradient approximation. The single crystal elastic constants are numerically estimated using strain–stress approach. The polycrystalline aggregate elastic parameters are calculated from the single elastic constants via the Voigt–Reuss–Hill approximations. Subsequently, the ductility and brittleness are characterized with the estimation from Pugh’s rule (B/G) and Cauchy pressure. Additionally, the Debye temperature is calculated from the average elastic wave velocity obtained from bulk and shear moduli. The calculated parameters are consistent with the previous experimental and theoretical data. These borides are both mechanically and dynamically stable in the considered structure.

  17. Discovery of Protein Phosphatase 2C Inhibitors by Virtual Screening

    PubMed Central

    Rogers, Jessica P.; Beuscher, Albert E.; Flajolet, Marc; McAvoy, Thomas; Nairn, Angus C.; Olson, Arthur; Greengard, Paul

    2008-01-01

    Protein phosphatase 2C (PP2C) is an archetype of the PPM Ser/Thr phosphatases, characterized by dependence on divalent magnesium or manganese cofactors, absence of known regulatory proteins, and resistance to all known Ser/Thr phosphatase inhibitors. We have used virtual ligand screening with the AutoDock method and the National Cancer Institute Diversity Set to identify small molecule inhibitors of PP2Cα activity at a protein substrate. These inhibitors are active in the micromolar range, and represent the first non-phosphate-based molecules found to inhibit a type 2C phosphatase. The compounds docked to three recurrent binding sites near the PP2Cα active site and displayed novel Ser/Thr phosphatase selectivity profiles. Common chemical features of these compounds may form the basis for development of a PP2C inhibitor pharmacophore and may facilitate investigation of PP2C control and cellular function. PMID:16509582

  18. Monovalent cation and amiloride analog modulation of adrenergic ligand binding to the unglycosylated alpha 2B-adrenergic receptor subtype

    SciTech Connect

    Wilson, A.L.; Seibert, K.; Brandon, S.; Cragoe, E.J. Jr.; Limbird, L.E. )

    1991-04-01

    The unglycosylated alpha 2B subtype of the alpha 2-adrenergic receptor found in NG-108-15 cells possesses allosteric regulation of adrenergic ligand binding by monovalent cations and 5-amino-substituted amiloride analogs. These findings demonstrate that allosteric modulation of adrenergic ligand binding is not a property unique to the alpha 2A subtype. The observation that amiloride analogs as well as monovalent cations can modulate adrenergic ligand binding to the nonglycosylated alpha 2B subtype indicates that charge shielding due to carbohydrate moieties does not play a role in this allosteric modulation but, rather, these regulatory effects result from interactions of cations and amiloride analogs with the protein moiety of the receptor. Furthermore, the observation that both alpha 2A and alpha 2B receptor subtypes are modulated by amiloride analogs suggests that structural domains that are conserved between the two are likely to be involved in this allosteric modulation.

  19. Luminescent gold and silver complexes with the monophosphane 1-(PPh2)-2-Me-C2B10H10 and their conversion to gold micro- and superstructured materials.

    PubMed

    Crespo, Olga; Díaz, Carlos; O'Dwyer, Colm; Gimeno, M Concepción; Laguna, Antonio; Ospino, Isaura; Valenzuela, Maria Luisa

    2014-07-21

    Gold and silver complexes containing the monophosphane 1-PPh2-2-Me-l,2-C2B10H10 with different coordination numbers (2, 3) have been synthesized: [M(7,8-(PPh2)2-C2B9H10)(1-PPh2-2-Me-C2B10H10)] (M = Ag, Au) and [Au2(μ-1,n-C2B10H10)(1-PPh2-2-Me-C2B10H10)2] (n = 2, 12). Solid-state pyrolysis of [AuCl(1-PPh2-2-Me-C2B10H10)] and [Au2(μ-1,12-C2B10H10)(1-PPh2-2-Me-C2B10H10)2] in air and of solutions of [AuCl(1-PPh2-2-Me-C2B10H10)] deposited on silicon and silica at 800 °C results in single-crystal Au, confirmed by diffraction and SEM-EDS. The morphology of the pyrolytic products depends on the thermolytic conditions, and different novel 3-D superstructures or microcrystals are possible. We also propose a mechanism for the thermal conversion of these precursors to structural crystalline and phase pure materials. The presence of the carborane monophosphane seems to originate quenching of the luminescence at room temperature in the complexes [Au2(μ-1,n-C2B10H10)(1-PPh2-2-Me-C2B10H10)2], in comparison with other [Au2(μ-1,n-C2B10H10)L2] species (L = monophosphane).

  20. Confirmation of Y haplogroup tree topologies with newly suggested Y-SNPs for the C2, O2b and O3a subhaplogroups.

    PubMed

    Kwon, So Yeun; Lee, Hwan Young; Lee, Eun Young; Yang, Woo Ick; Shin, Kyoung-Jin

    2015-11-01

    Y chromosome single nucleotide polymorphisms (Y-SNPs) are useful markers for reconstructing male lineages through hierarchically arranged allelic sets known as haplogroups, and are thereby widely used in the fields such as human evolution, anthropology and forensic genetics. The Y haplogroup tree was recently revised with newly suggested Y-SNP markers for designation of several subgroups of haplogroups C2, O2b and O3a, which are predominant in Koreans. Therefore, herein we analyzed these newly suggested Y-SNPs in 545 unrelated Korean males who belong to the haplogroups C2, O2b or O3a, and investigated the reconstructed topology of the Y haplogroup tree. We were able to confirm that markers L1373, Z1338/JST002613-27, Z1300, CTS2657, Z8440 and F845 define the C2 subhaplogroups, C2b, C2e, C2e1, C2e1a, C2e1b and C2e2, respectively, and that markers F3356, L682, F11, F238/F449 and F444 define the O subhaplogroups O2b1, O2b1b, O3a1c1, O3a1c2 and O3a2c1c, respectively. Among six C2 subhaplogroups (C2b, C2e, C2e1*, C2e1a, C2e1b and C2e2), the C2e haplogroup and its subhaplogroups were found to be predominant, and among the four O2b subhaplogroups (O2b*, O2b1*, O2b1a and O2b1b), O2b1b was most frequently observed. Among the O3a subhaplogroups, O3a2c1 was predominant and it was further divided into the subhaplogroups O3a2c1a and O3a2c1c with a newly suggested marker. However, the JST002613-27 marker, which had been known to define the haplogroup C2f, was found to be an ancestral marker of the C2e haplogroup, as is the Z1338 marker. Also, the M312 marker for the O2b1 haplogroup designation was replaced by F3356, because all of the O2b1 haplotypes showed a nucleotide change at F3356, but not at M312. In addition, the F238 marker was always observed to be phylogenetically equivalent to F449, while both of the markers were assigned to the O3a1c2 haplogroup. The confirmed phylogenetic tree of this study with the newly suggested Y-SNPs could be valuable for anthropological and

  1. The 2-C-methylerythritol 4-phosphate pathway in melon is regulated by specialized isoforms for the first and last steps.

    PubMed

    Saladié, Montserrat; Wright, Louwrance P; Garcia-Mas, Jordi; Rodriguez-Concepcion, Manuel; Phillips, Michael A

    2014-09-01

    The 2-C-methyl-d-erythritol-4-phosphate (MEP) pathway provides the precursors for the biosynthesis of plastidial isoprenoids, which include the carotenoid pigments of many fruits. We have analysed the genes encoding the seven enzymes of the MEP pathway in melon (Cucumis melo L.) and determined that the first one, 1-deoxyxylulose 5-phosphate synthase (DXS), and the last one, 1-hydroxy-2-methyl-2-(E)-butenyl 4-diphosphate reductase (HDR), are represented in the genome as a small gene family and paralogous pair, respectively. In the case of DXS, three genes encode functional DXS activities which fall into previously established type I (CmDXS1) and II (CmDXS2a and CmDXS2b) categories, while a fourth DXS-like gene belonging to the type III group did not encode a protein with DXS activity. Their expression patterns and phylogenies suggest that CmDXS1 is functionally specialized for developmental and photosynthetic processes, while CmDXS2a and CmDXS2b are induced in flowers and ripening fruit of orange- (but not white-) fleshed varieties, coinciding with β-carotene accumulation. This is the first instance connecting type II DXS genes to specialized isoprenoid biosynthesis in the fruit of an agronomically important species. Two HDR paralogues were shown to encode functional enzymes, although only CmHDR1 was highly expressed in the tissues and developmental stages tested. Phylogenetic analysis showed that in cucurbits such as melon, these HDR paralogues probably arose through individual gene duplications in a common angiosperm ancestor, mimicking a prior division in gymnosperms, while other flowering plants, including apple, soy, canola, and poplar, acquired HDR duplicates recently as homoeologues through large-scale genome duplications. We report the influence of gene duplication history on the regulation of the MEP pathway in melon and the role of specialized MEP-pathway isoforms in providing precursors for β-carotene production in orange-fleshed melon varieties.

  2. Evaluation of 89 compounds for identification of substrates for cynomolgus monkey CYP2C76, a new bupropion/nifedipine oxidase.

    PubMed

    Hosaka, Shinya; Murayama, Norie; Satsukawa, Masahiro; Shimizu, Makiko; Uehara, Shotaro; Fujino, Hideki; Iwasaki, Kazuhide; Iwano, Shunsuke; Uno, Yasuhiro; Yamazaki, Hiroshi

    2015-01-01

    Cynomolgus monkeys are widely used in preclinical studies during drug development because of their evolutionary closeness to humans, including their cytochrome P450s (P450s). Most cynomolgus monkey P450s are almost identical (≥90%) to human P450s; however, CYP2C76 has low sequence identity (approximately 80%) to any human CYP2Cs. Although CYP2C76 has no ortholog in humans and is partly responsible for species differences in drug metabolism between cynomolgus monkeys and humans, a broad evaluation of potential substrates for CYP2C76 has not yet been conducted. In this study, a screening of 89 marketed compounds, including human CYP2C and non-CYP2C substrates or inhibitors, was conducted to find potential CYP2C76 substrates. Among the compounds screened, 19 chemicals were identified as substrates for CYP2C76, including substrates for human CYP1A2 (7-ethoxyresorufin), CYP2B6 (bupropion), CYP2D6 (dextromethorphan), and CYP3A4/5 (dextromethorphan and nifedipine), and inhibitors for CYP2B6 (sertraline, clopidogrel, and ticlopidine), CYP2C8 (quercetin), CYP2C19 (ticlopidine and nootkatone), and CYP3A4/5 (troleandomycin). CYP2C76 metabolized a wide variety of the compounds with diverse structures. Among them, bupropion and nifedipine showed high selectivity to CYP2C76. As for nifedipine, CYP2C76 formed methylhydroxylated nifedipine, which was not produced by monkey CYP2C9, CYP2C19, or CYP3A4, as identified by mass spectrometry and estimated by a molecular docking simulation. This unique oxidative metabolite formation of nifedipine could be one of the selective marker reactions of CYP2C76 among the major CYP2Cs and CYP3As tested. These results suggest that monkey CYP2C76 contributes to bupropion hydroxylation and formation of different nifedipine oxidative metabolites as a result of its relatively large substrate cavity.

  3. Evaluation of 89 compounds for identification of substrates for cynomolgus monkey CYP2C76, a new bupropion/nifedipine oxidase.

    PubMed

    Hosaka, Shinya; Murayama, Norie; Satsukawa, Masahiro; Shimizu, Makiko; Uehara, Shotaro; Fujino, Hideki; Iwasaki, Kazuhide; Iwano, Shunsuke; Uno, Yasuhiro; Yamazaki, Hiroshi

    2015-01-01

    Cynomolgus monkeys are widely used in preclinical studies during drug development because of their evolutionary closeness to humans, including their cytochrome P450s (P450s). Most cynomolgus monkey P450s are almost identical (≥90%) to human P450s; however, CYP2C76 has low sequence identity (approximately 80%) to any human CYP2Cs. Although CYP2C76 has no ortholog in humans and is partly responsible for species differences in drug metabolism between cynomolgus monkeys and humans, a broad evaluation of potential substrates for CYP2C76 has not yet been conducted. In this study, a screening of 89 marketed compounds, including human CYP2C and non-CYP2C substrates or inhibitors, was conducted to find potential CYP2C76 substrates. Among the compounds screened, 19 chemicals were identified as substrates for CYP2C76, including substrates for human CYP1A2 (7-ethoxyresorufin), CYP2B6 (bupropion), CYP2D6 (dextromethorphan), and CYP3A4/5 (dextromethorphan and nifedipine), and inhibitors for CYP2B6 (sertraline, clopidogrel, and ticlopidine), CYP2C8 (quercetin), CYP2C19 (ticlopidine and nootkatone), and CYP3A4/5 (troleandomycin). CYP2C76 metabolized a wide variety of the compounds with diverse structures. Among them, bupropion and nifedipine showed high selectivity to CYP2C76. As for nifedipine, CYP2C76 formed methylhydroxylated nifedipine, which was not produced by monkey CYP2C9, CYP2C19, or CYP3A4, as identified by mass spectrometry and estimated by a molecular docking simulation. This unique oxidative metabolite formation of nifedipine could be one of the selective marker reactions of CYP2C76 among the major CYP2Cs and CYP3As tested. These results suggest that monkey CYP2C76 contributes to bupropion hydroxylation and formation of different nifedipine oxidative metabolites as a result of its relatively large substrate cavity. PMID:25318994

  4. Allele frequency distribution of CYP2C9 2 and CYP2C9 3 polymorphisms in six Mexican populations.

    PubMed

    Castelán-Martínez, Osvaldo D; Hoyo-Vadillo, Carlos; Sandoval-García, Emmanuel; Sandoval-Ramírez, Lucila; González-Ibarra, Miriam; Solano-Solano, Gloria; Gómez-Díaz, Rita A; Parra, Esteban J; Cruz, Miguel; Valladares-Salgado, Adán

    2013-07-10

    Allele frequency differences of functional CYP2C9 polymorphisms are responsible for some of the variation in drug response observed in human populations. The most relevant CYP2C9 functional variants are CYP2C9*2 (rs1799853) and CYP2C9 3 (rs1057910). These polymorphisms show variation in allele frequencies among different population groups. The present study aimed to analyze these polymorphisms in 947 Mexican-Mestizo from Mexico City and 483 individuals from five indigenous Mexican populations: Nahua, Teenek, Tarahumara, Purepecha and Huichol. The CYP2C9*2 allele frequencies in the Mestizo, Nahua and Teenek populations were 0.051, 0.007 and 0.005, respectively. As for CYP2C9 3, the allelic frequencies in the Mestizo, Nahua and Teenek populations were 0.04, 0.005 and 0.005, respectively. The CYP2C9 2 and CYP2C9 3 alleles were not observed in the Tarahumara, Purepecha and Huichol populations. These findings are in agreement with previous studies reporting very low allele frequencies for these polymorphisms in American Indigenous populations.

  5. Targeting the A2B adenosine receptor during gastrointestinal ischemia and inflammation

    PubMed Central

    Eltzschig, Holger K; Rivera-Nieves, Jesus; Colgan, Sean P

    2014-01-01

    Extracellular adenosine functions as an endogenous distress signal via activation of four distinct adenosine receptors (A1, A2A, A2B and A3). Conditions of limited oxygen availability or acute inflammation lead to elevated levels of extracellular adenosine and enhanced signaling events. This relates to a combination of four mechanisms: i) increased production of adenosine via extracellular phosphohydrolysis of precursor molecules (particularly ATP and ADP); ii) increased expression and signaling via hypoxia-induced adenosine receptors, particularly the A2B adenosine receptor; iii) attenuated uptake from the extracellular towards the intracellular compartment; and iv) attenuated intracellular metabolism. Due to their large surface area, mucosal organs are particularly prone to hypoxia and ischemia associated inflammation. Therefore, it is not surprising that adenosine production and signaling plays a central role in attenuating tissue inflammation and injury during intestinal ischemia or inflammation. In fact, recent studies combining pharmacological and genetic approaches demonstrated that adenosine signaling via the A2B adenosine receptor dampens mucosal inflammation and tissue injury during intestinal ischemia or experimental colitis. This review outlines basic principles of extracellular adenosine production, signaling, uptake and metabolism. In addition, we discuss the role of this pathway in dampening hypoxia-elicited inflammation, specifically in the setting of intestinal ischemia and inflammation. PMID:19769545

  6. Arabidopsis DREB2C modulates ABA biosynthesis during germination.

    PubMed

    Je, Jihyun; Chen, Huan; Song, Chieun; Lim, Chae Oh

    2014-09-12

    Plant dehydration-responsive element binding factors (DREBs) are transcriptional regulators of the APETELA2/Ethylene Responsive element-binding Factor (AP2/ERF) family that control expression of abiotic stress-related genes. We show here that under conditions of mild heat stress, constitutive overexpression seeds of transgenic DREB2C overexpression Arabidopsis exhibit delayed germination and increased abscisic acid (ABA) content compared to untransformed wild-type (WT). Treatment with fluridone, an inhibitor of the ABA biosynthesis abrogated these effects. Expression of an ABA biosynthesis-related gene, 9-cis-epoxycarotenoid dioxygenase 9 (NCED9) was up-regulated in the DREB2C overexpression lines compared to WT. DREB2C was able to trans-activate expression of NCED9 in Arabidopsis leaf protoplasts in vitro. Direct and specific binding of DREB2C to a complete DRE on the NCED9 promoter was observed in electrophoretic mobility shift assays. Exogenous ABA treatment induced DREB2C expression in germinating seeds of WT. Vegetative growth of transgenic DREB2C overexpression lines was more strongly inhibited by exogenous ABA compared to WT. These results suggest that DREB2C is a stress- and ABA-inducible gene that acts as a positive regulator of ABA biosynthesis in germinating seeds through activating NCED9 expression.

  7. The Preparation and Characterization of INTEC Phase 2b Composition Variation Study Glasses

    SciTech Connect

    B. A. Staples; B. A. Scholes; L. L. Torres; C. A. Musick; B. R. Boyle; D. K. Peeler; J. D. Vienna

    2000-02-01

    The second phase of the composition variation study (CVS) for the development of glass compositions to immobilize Idaho Nuclear Technology and Engineering Center (INTEC) high level wastes (HLW) is complete. This phase of the CVS addressed waste composition of high activity waste fractions (HAW) from the initial separations flowsheet. Updated estimates if INTEC calcined HLW compositions and of high activity waste fractions proposed to be separated from dissolved calcine were used as the waste component for this CVS phase. These wastes are of particular interest because high aluminum, calcium, zirconium, fluorine, potassium, and low iron and sodium content places them outside the vitrification experience in the Department of Energy complex. Because of the presence of calcium and fluorine, two major zirconia calcine components not addressed in Phase I, a series of scooping tests, designated Phase 2a, were performed. The results of these tests provided information on the effects of calcium and fluoride solubility and their impacts on product properties and composition boundary information for Phase 2b. Details and results of Phase 2a are reported separately. Through application of statistical techniques and the results of Phase 2a, a test matrix was defined for Phase 2b of the CVS. From this matrix, formulations were systematically selected for preparation and characterization with respect to visual and optical homogeneity, viscosity as a function of melt temperature, liquidus temperature (TL), and leaching properties based on response to the product consistency test. The results of preparing and characterizing the Phase 2b glasses are presented in this document. Based on the results, several formulations investigated have suitable properties for further development. A full analysis of the composition-product characteristic relationship of glasses being developed for immobilizing INTEC wastes will be performed at the completion of composition-property relationship

  8. Magnetospheric Multiscale Mission (MMS) Phase 2B Navigation Performance

    NASA Technical Reports Server (NTRS)

    Scaperoth, Paige Thomas; Long, Anne; Carpenter, Russell

    2009-01-01

    The Magnetospheric Multiscale (MMS) formation flying mission, which consists of four spacecraft flying in a tetrahedral formation, has challenging navigation requirements associated with determining and maintaining the relative separations required to meet the science requirements. The baseline navigation concept for MMS is for each spacecraft to independently estimate its position, velocity and clock states using GPS pseudorange data provided by the Goddard Space Flight Center-developed Navigator receiver and maneuver acceleration measurements provided by the spacecraft's attitude control subsystem. State estimation is performed onboard in real-time using the Goddard Enhanced Onboard Navigation System flight software, which is embedded in the Navigator receiver. The current concept of operations for formation maintenance consists of a sequence of two maintenance maneuvers that is performed every 2 weeks. Phase 2b of the MMS mission, in which the spacecraft are in 1.2 x 25 Earth radii orbits with nominal separations at apogee ranging from 30 km to 400 km, has the most challenging navigation requirements because, during this phase, GPS signal acquisition is restricted to less than one day of the 2.8-day orbit. This paper summarizes the results from high-fidelity simulations to determine if the MMS navigation requirements can be met between and immediately following the maintenance maneuver sequence in Phase 2b.

  9. Identification of a new transcriptional initiation site and the corresponding functional gene 2b in the murine coronavirus RNA genome.

    PubMed Central

    Shieh, C K; Lee, H J; Yokomori, K; La Monica, N; Makino, S; Lai, M M

    1989-01-01

    We have previously shown that some strains of the murine coronavirus mouse hepatitis virus (MHV) synthesize an additional mRNA species (mRNA 2b, previously called mRNA 2a) with a size intermediate between that of mRNAs 2 and 3, suggesting the presence of an optional transcriptional initiation site. This transcriptional start is dependent on the leader sequence of the virus strains. To study the mechanism of coronavirus transcriptional regulation, we have cloned and sequenced the region of the viral genome corresponding to the 5' unique coding region of mRNA 2 of the JHM strain of MHV. In addition to the open reading frame (ORF) predicted to encode the viral nonstructural protein p30, a second complete ORF, with the potential to encode a 439-amino-acid polypeptide, was discovered. The transcriptional initiation sites of both mRNA 2a (formerly called mRNA 2) and mRNA 2b were determined by primer extension studies and RNA sequencing. The data indicated that transcription of mRNA 2a initiated at a site, UCUAUAC, that resembled the consensus intergenic sequence. In contrast, the start signal of the optional mRNA 2b, UAAUAAAC, deviated from the consensus sequence. mRNA 2b is a functional mRNA, as shown by in vitro translation studies of mRNA and ORF 2b and by the detection of an additional viral structural protein, gp65, in the JHM strain that synthesized this mRNA. Although the A59 strain of MHV was found to retain ORF 2b, it lacked the correct transcriptional and translational start signals for this gene. This study has therefore identified an optional gene product for murine coronaviruses and provided insights into the mechanism of regulation of MHV RNA transcription. Images PMID:2547994

  10. Meconium Ileus Caused by Mutations in GUCY2C, Encoding the CFTR-Activating Guanylate Cyclase 2C

    PubMed Central

    Romi, Hila; Cohen, Idan; Landau, Daniella; Alkrinawi, Suliman; Yerushalmi, Baruch; Hershkovitz, Reli; Newman-Heiman, Nitza; Cutting, Garry R.; Ofir, Rivka; Sivan, Sara; Birk, Ohad S.

    2012-01-01

    Meconium ileus, intestinal obstruction in the newborn, is caused in most cases by CFTR mutations modulated by yet-unidentified modifier genes. We now show that in two unrelated consanguineous Bedouin kindreds, an autosomal-recessive phenotype of meconium ileus that is not associated with cystic fibrosis (CF) is caused by different homozygous mutations in GUCY2C, leading to a dramatic reduction or fully abrogating the enzymatic activity of the encoded guanlyl cyclase 2C. GUCY2C is a transmembrane receptor whose extracellular domain is activated by either the endogenous ligands, guanylin and related peptide uroguanylin, or by an external ligand, Escherichia coli (E. coli) heat-stable enterotoxin STa. GUCY2C is expressed in the human intestine, and the encoded protein activates the CFTR protein through local generation of cGMP. Thus, GUCY2C is a likely candidate modifier of the meconium ileus phenotype in CF. Because GUCY2C heterozygous and homozygous mutant mice are resistant to E. coli STa enterotoxin-induced diarrhea, it is plausible that GUCY2C mutations in the desert-dwelling Bedouin kindred are of selective advantage. PMID:22521417

  11. The interstellar chemistry of H2C3O isomers

    NASA Astrophysics Data System (ADS)

    Loison, Jean-Christophe; Agúndez, Marcelino; Marcelino, Núria; Wakelam, Valentine; Hickson, Kevin M.; Cernicharo, José; Gerin, Maryvonne; Roueff, Evelyne; Guélin, Michel

    2016-03-01

    We present the detection of two H2C3O isomers, propynal and cyclopropenone, toward various starless cores and molecular clouds, together with upper limits for the third isomer propadienone. We review the processes controlling the abundances of H2C3O isomers in interstellar media showing that the reactions involved are gas-phase ones. We show that the abundances of these species are controlled by kinetic rather than thermodynamic effects.

  12. The interstellar chemistry of H2C3O isomers

    PubMed Central

    Loison, Jean-Christophe; Agúndez, Marcelino; Marcelino, Núria; Wakelam, Valentine; Hickson, Kevin M.; Cernicharo, José; Gerin, Maryvonne; Roueff, Evelyne; Guélin, Michel

    2016-01-01

    We present the detection of two H2C3O isomers, propynal and cyclopropenone, toward various starless cores and molecular clouds, together with upper limits for the third isomer propadienone. We review the processes controlling the abundances of H2C3O isomers in interstellar media showing that the reactions involved are gas-phase ones. We show that the abundances of these species are controlled by kinetic rather than thermodynamic effects. PMID:27013768

  13. In vitro anti-Giardia lamblia activity of 2-aryl-3-hydroxymethyl imidazo[1,2-a]pyridines and -pyrimidines, individually and in combination with albendazole.

    PubMed

    Velázquez-Olvera, Stephanía; Salgado-Zamora, Héctor; Jiménez-Cardoso, Enedina; Campos-Aldrete, Maria-Elena; Pérez-González, Cuauhtémoc; Ben Hadda, Taibi

    2016-03-01

    Giardiasis is a major diarrheal disease found throughout the world, the causative agent being the flagellate protozoan Giardia intestinalis. Infection is more common in children than in adults. The appearance of drug resistance has complicated the treatment of several parasitic diseases, including giardiasis. Thus, the aim of this investigation was to make an in vitro evaluation of the antigiardia response of synthetic derivatives 2-aryl-3-hydroxymethylimidazo[1,2-a]pyridines 1 and -pyrimidines 2 against trophozoites of Giardia lamblia WB, in comparison with the reference drug, albendazole. Additionally, the synergistic action of albendazole in combination with each of the most active 2-aryl-3-hydroxymethyl imidazo[1,2-a]pyridines and pyrimidines was also assessed. Based on the IC50 values obtained, the best anti-Giardia activity was provided by the 3-hydroxymethyl-4-fluorophenylimidazo[1,2-a]pyrimidine derivative 2c and the corresponding imidazo[1,2-a]pyrimidine with the p-tolyl substituent 2d, followed by 2a and 2b. These four compounds showed effectiveness at a concentration similar to that of albendazole. Regarding synergism, the IC50 of the combination of albendazole with 2a, 2b or 2c gave the best anti-Giardia action, showing greater efficacy than albendazole alone. Hence, G. lamblia WB showed high susceptibility to some 2-aryl-3-hydroxymethyl imidazo[1,2-a] pyrimidines, which acted synergistically when used in combination with albendazole. PMID:26657313

  14. Human T Cell Lymphotropic Virus Type 2a Strains Among HIV Type 1-Coinfected Patients from Brazil Have Originated Mostly from Brazilian Amerindians

    PubMed Central

    Magri, Mariana Cavalheiro; Brigido, Luis Fernando de Macedo; Morimoto, Helena Kaminami

    2013-01-01

    Abstract The human T cell lymphotropic virus type 2 (HTLV-2) is found mainly in Amerindians and in intravenous drug users (IDUs) from urban areas of the United States, Europe, and Latin America. Worldwide, HTLV-2a and HTLV-2b subtypes are the most prevalent. Phylogenetic analysis of HTLV-2 isolates from Brazil showed the HTLV-2a subtype, variant -2c, which spread from Indians to the general population and IDUs. The present study searched for the types of HTLV-2 that predominate among HIV-1-coinfected patients from southern and southeastern Brazil. Molecular characterization of the LTR, env, and tax regions of 38 isolates confirmed the HTLV-2c variant in 37 patients, and one HTLV-2b in a patient from Paraguay. Phylogenetic analysis of sequences showed different clades of HTLV-2 associated with risk factors and geographic region. These clades could represent different routes of virus transmission and/or little diverse evolutionary rates of virus. Taking into account the results obtained in the present study and the lack of the prototypic North American HTLV-2a strain and HTLV-2b subtypes commonly detected among HIV-coinfected individuals worldwide, we could speculate on the introduction of Brazilian HTLV-2 strains in such populations before the introduction of HIV. PMID:23484539

  15. Human T cell lymphotropic virus type 2a strains among HIV type 1-coinfected patients from Brazil have originated mostly from Brazilian Amerindians.

    PubMed

    Magri, Mariana Cavalheiro; Brigido, Luis Fernando de Macedo; Morimoto, Helena Kaminami; Caterino-de-Araujo, Adele

    2013-07-01

    The human T cell lymphotropic virus type 2 (HTLV-2) is found mainly in Amerindians and in intravenous drug users (IDUs) from urban areas of the United States, Europe, and Latin America. Worldwide, HTLV-2a and HTLV-2b subtypes are the most prevalent. Phylogenetic analysis of HTLV-2 isolates from Brazil showed the HTLV-2a subtype, variant -2c, which spread from Indians to the general population and IDUs. The present study searched for the types of HTLV-2 that predominate among HIV-1-coinfected patients from southern and southeastern Brazil. Molecular characterization of the LTR, env, and tax regions of 38 isolates confirmed the HTLV-2c variant in 37 patients, and one HTLV-2b in a patient from Paraguay. Phylogenetic analysis of sequences showed different clades of HTLV-2 associated with risk factors and geographic region. These clades could represent different routes of virus transmission and/or little diverse evolutionary rates of virus. Taking into account the results obtained in the present study and the lack of the prototypic North American HTLV-2a strain and HTLV-2b subtypes commonly detected among HIV-coinfected individuals worldwide, we could speculate on the introduction of Brazilian HTLV-2 strains in such populations before the introduction of HIV.

  16. Gene order for rubella virus structural proteins is NH/sub 2/-C-E2-E1-COOH

    SciTech Connect

    Oker-Blom, C.

    1984-08-01

    The order of translation in vivo of the genes coding for rubella virus structural proteins was studied in infected B-Vero cells. The proteins were sequentially pulse-chase labeled with (/sup 35/S)methionine after synchronization of translation initiation with hypertonic salt treatment. A sequential labeling procedure (window-labeling) to specifically label defined segments of the structural proteins was also used. The labeled proteins were identified by sodium dodecyl sulfate-gel electrophoresis after immunoprecipitation with specific antisera directed against the two virion glycoproteins (E1 and E2a/E2b) and the nucleocapsid (C) protein. The order of translation was found to be NH/sub 2/-C-E2-E1-COOH. We have previously shown that the structural proteins are synthesized in vitro from a cytoplasmic 24S subgenomic mRNA as a 110,000-dalton (p110) precursor. Here, it is shown that p110 is precipitated with anti-C, anti-E2, and anti-E1 sera, indicating that p110 is the precursor of all three structural proteins. Two major in vitro translation products (M/sub r/s, 66,000 and 62,000) that could represent preterminated polypeptide chains or proteolytic cleavage products were precipitated with anti-C and anti-Es sera, but not with anti-E1 serum, indicating, in conformity with the in vivo results, that the genes for the C and E2 proteins are adjacent to each other. Using these specific antisera, we have also confirmed the identity of the unglycosylated forms of E1 (M/sub r/, 53,000) and E2 (M/sub r/ 30,000) immunoprecipitated from tunicamycin-treated infected cells. 18 references, 6 figures.

  17. The cyclotron energization through auroral wave experiments (CENTAUR 2B)

    NASA Technical Reports Server (NTRS)

    Winningham, J. D.

    1992-01-01

    The CENTAUR 2B mission, a dual payload program, is in many aspects the same as the previous missions from Cape Perry and Norway in 1985. It was planned that these payloads would be launched from Andoya, Norway, Nov. 1989 from the Universal II launcher. The payloads are identical, but would have been launched at different azimuths as far north and as far west as possible. Particle experiments include the angular resolving energy analyzer (AREA), the fast ion mass spectrometer (FIMS), the spectrographic particle images (SPI), and finally, the differential ion flux probe (DIFP). SwRI was responsible for the scientific payload, which includes the power supplies, the power supply interfacing, the manipulating of the data from the instruments to format it for the telemetry system, all mechanical structure and restraint mechanisms, and the payload subskin. The status of the various components of this program is given.

  18. Semantic ETL into i2b2 with Eureka!

    PubMed Central

    Post, Andrew R.; Krc, Tahsin; Rathod, Himanshu; Agravat, Sanjay; Mansour, Michel; Torian, William; Saltz, Joel H.

    Clinical phenotyping is an emerging research information systems capability. Research uses of electronic health record (EHR) data may require the ability to identify clinical co-morbidities and complications. Such phenotypes may not be represented directly as discrete data elements, but rather as frequency, sequential and temporal patterns in billing and clinical data. These patterns’ complexity suggests the need for a robust yet flexible extract, transform and load (ETL) process that can compute them. This capability should be accessible to investigators with limited ability to engage an IT department in data management. We have developed such a system, Eureka! Clinical Analytics. It extracts data from an Excel spreadsheet, computes a broad set of phenotypes of common interest, and loads both raw and computed data into an i2b2 project. A web-based user interface allows executing and monitoring ETL processes. Eureka! is deployed at our institution and is available for deployment in the cloud. PMID:24303265

  19. Semantic ETL into i2b2 with Eureka!

    PubMed

    Post, Andrew R; Krc, Tahsin; Rathod, Himanshu; Agravat, Sanjay; Mansour, Michel; Torian, William; Saltz, Joel H

    2013-01-01

    Clinical phenotyping is an emerging research information systems capability. Research uses of electronic health record (EHR) data may require the ability to identify clinical co-morbidities and complications. Such phenotypes may not be represented directly as discrete data elements, but rather as frequency, sequential and temporal patterns in billing and clinical data. These patterns' complexity suggests the need for a robust yet flexible extract, transform and load (ETL) process that can compute them. This capability should be accessible to investigators with limited ability to engage an IT department in data management. We have developed such a system, Eureka! Clinical Analytics. It extracts data from an Excel spreadsheet, computes a broad set of phenotypes of common interest, and loads both raw and computed data into an i2b2 project. A web-based user interface allows executing and monitoring ETL processes. Eureka! is deployed at our institution and is available for deployment in the cloud. PMID:24303265

  20. Study of Subsonic Flow Over a TOW 2B Missile

    NASA Astrophysics Data System (ADS)

    Goudarzi, Koorosh; Jamali, Mehdi

    2016-01-01

    The objective of this investigation is to study the subsonic flow over a missile. In this paper, a model of TOW 2B missile is studied. Two computational approaches are being explored, namely solutions based on the Reynolds-averaged compressible Navier-Stokes equations and solutions based on the inviscid flow (small disturbance theory). The simulations are performed at the Mach number of 0.6, 0.7, 0.8, 0.9 and 1.0 at four angles of attack of 2, 4, 6 and 8 degree. Results obtained from analytical simulation are compared with numerical data. It is found that lift and drag coefficients would go up by increasing of the angle of attack and the Mach number. Trend of changes of the results that obtained from the small disturbance theory is roughly as same as the numeric solution.

  1. Semantic ETL into i2b2 with Eureka!

    PubMed

    Post, Andrew R; Krc, Tahsin; Rathod, Himanshu; Agravat, Sanjay; Mansour, Michel; Torian, William; Saltz, Joel H

    2013-01-01

    Clinical phenotyping is an emerging research information systems capability. Research uses of electronic health record (EHR) data may require the ability to identify clinical co-morbidities and complications. Such phenotypes may not be represented directly as discrete data elements, but rather as frequency, sequential and temporal patterns in billing and clinical data. These patterns' complexity suggests the need for a robust yet flexible extract, transform and load (ETL) process that can compute them. This capability should be accessible to investigators with limited ability to engage an IT department in data management. We have developed such a system, Eureka! Clinical Analytics. It extracts data from an Excel spreadsheet, computes a broad set of phenotypes of common interest, and loads both raw and computed data into an i2b2 project. A web-based user interface allows executing and monitoring ETL processes. Eureka! is deployed at our institution and is available for deployment in the cloud.

  2. Integrated Product and Process Data for B2B Collaboration

    SciTech Connect

    Kulvatunyou, Boonserm; Ivezic, Nenad; Jones, Albert; Wysk, Richard A.

    2003-09-01

    Collaborative development of engineered products in a business-to-business (B2B) environment will require more than just the selection of components from an on-line catalogue. It will involve the electronic exchange of product, process, and production engineering information during both design and manufacturing. While the state-of-the-practice does include a variety of ways to exchange product data electronically, it does not extend to the exchange of manufacturing process data. The reason is simple; process data is usually tied to specific manufacturing resources. These resources are not known typically at product development time. This paper proposes an approach, called an Integrated Product and Process Data (IPPD), where manufacturing process data is considered during product development. This approach replaces traditional process plans, which are resource specific, with a resource-independent process representation. Such a representation will allow a much wider collaboration among business partners and provide the necessary base for collaborative product development.

  3. Structure of human nucleosome containing the testis-specific histone variant TSH2B

    SciTech Connect

    Urahama, Takashi; Horikoshi, Naoki; Osakabe, Akihisa; Tachiwana, Hiroaki; Kurumizaka, Hitoshi

    2014-03-25

    The crystal structure of human nucleosome containing the testis-specific TSH2B variant has been determined. The TSH2B Ser85 residue does not interact with H4 in the nucleosome, and induces a local structural difference between TSH2B and H2B in nucleosomes. The human histone H2B variant TSH2B is highly expressed in testis and may function in the chromatin transition during spermatogenesis. In the present study, the crystal structure of the human testis-specific nucleosome containing TSH2B was determined at 2.8 Å resolution. A local structural difference between TSH2B and canonical H2B in nucleosomes was detected around the TSH2B-specific amino-acid residue Ser85. The TSH2B Ser85 residue does not interact with H4 in the nucleosome, but in the canonical nucleosome the H2B Asn84 residue (corresponding to the TSH2B Ser85 residue) forms water-mediated hydrogen bonds with the H4 Arg78 residue. In contrast, the other TSH2B-specific amino-acid residues did not induce any significant local structural changes in the TSH2B nucleosome. These findings may provide important information for understanding how testis-specific histone variants form nucleosomes during spermatogenesis.

  4. Computer simulation of the infrared spectra of endohedral metallofullerenes Li2C60 and Na2C60

    NASA Astrophysics Data System (ADS)

    Butyrskaya, E. V.; Zapryagaev, S. A.

    2009-03-01

    Using the Gaussian03 computer software, the infrared spectra of endohedral Li2C60 and Na2C60 are calculated by the Hartree-Fock method in the 3-21 G basis set. The calculation is carried out for three cases: (i) metallofullerenes without a solvent, (ii) metallofullerenes in a toluene solution, and (iii) metallofullerenes in a tetrahydrofuran solution. The effect of a solvent on the energetic, electrical, and spectral characteristics of the metallofullerenes is studied.

  5. Role of the C2B domain of synaptotagmin in vesicular release and recycling as determined by specific antibody injection into the squid giant synapse preterminal.

    PubMed

    Fukuda, M; Moreira, J E; Lewis, F M; Sugimori, M; Niinobe, M; Mikoshiba, K; Llinás, R

    1995-11-01

    Synaptotagmin (Syt) is an inositol high-polyphosphate series [IHPS inositol 1,3,4,5-tetrakisphosphate (IP4), inositol 1,3,4,5,6-pentakisphosphate, and inositol 1,2,3,4,5,6-hexakisphosphate] binding synaptic vesicle protein. A polyclonal antibody against the C2B domain (anti-Syt-C2B), an IHPS binding site, was produced. The specificity of this antibody to the C2B domain was determined by comparing its ability to inhibit IP4 binding to the C2B domain with that to inhibit the Ca2+/phospholipid binding to the C2A domain. Injection of the anti-Syt-C2B IgG into the squid giant presynapse did not block synaptic release. Coinjection of IP4 and anti-Syt-C2B IgG failed to block transmitter release, while IP4 itself was a powerful synpatic release blocker. Repetitive stimulation to presynaptic fiber injected with anti-Syt-C2B IgG demonstrated a rapid decline of the postsynaptic response amplitude probably due to its block of synaptic vesicle recycling. Electron microscopy of the anti-Syt-C2B-injected presynapse showed a 90% reduction of the numbers of synaptic vesicles. These results, taken together, indicate that the Syt molecule is central, in synaptic vesicle fusion by Ca2+ and its regulation by IHPS, as well as in the recycling of synaptic vesicles.

  6. Role of the C2B domain of synaptotagmin in vesicular release and recycling as determined by specific antibody injection into the squid giant synapse preterminal.

    PubMed Central

    Fukuda, M; Moreira, J E; Lewis, F M; Sugimori, M; Niinobe, M; Mikoshiba, K; Llinás, R

    1995-01-01

    Synaptotagmin (Syt) is an inositol high-polyphosphate series [IHPS inositol 1,3,4,5-tetrakisphosphate (IP4), inositol 1,3,4,5,6-pentakisphosphate, and inositol 1,2,3,4,5,6-hexakisphosphate] binding synaptic vesicle protein. A polyclonal antibody against the C2B domain (anti-Syt-C2B), an IHPS binding site, was produced. The specificity of this antibody to the C2B domain was determined by comparing its ability to inhibit IP4 binding to the C2B domain with that to inhibit the Ca2+/phospholipid binding to the C2A domain. Injection of the anti-Syt-C2B IgG into the squid giant presynapse did not block synaptic release. Coinjection of IP4 and anti-Syt-C2B IgG failed to block transmitter release, while IP4 itself was a powerful synpatic release blocker. Repetitive stimulation to presynaptic fiber injected with anti-Syt-C2B IgG demonstrated a rapid decline of the postsynaptic response amplitude probably due to its block of synaptic vesicle recycling. Electron microscopy of the anti-Syt-C2B-injected presynapse showed a 90% reduction of the numbers of synaptic vesicles. These results, taken together, indicate that the Syt molecule is central, in synaptic vesicle fusion by Ca2+ and its regulation by IHPS, as well as in the recycling of synaptic vesicles. Images Fig. 1 Fig. 2 Fig. 3 PMID:7479869

  7. Genome-wide ChIP-seq analysis of human TOP2B occupancy in MCF7 breast cancer epithelial cells

    PubMed Central

    Manville, Catriona M.; Smith, Kayleigh; Sondka, Zbyslaw; Rance, Holly; Cockell, Simon; Cowell, Ian G.; Lee, Ka Cheong; Morris, Nicholas J.; Padget, Kay; Jackson, Graham H.; Austin, Caroline A.

    2015-01-01

    ABSTRACT We report the whole genome ChIP seq for human TOP2B from MCF7 cells. Using three different peak calling methods, regions of binding were identified in the presence or absence of the nuclear hormone estradiol, as TOP2B has been reported to play a role in ligand-induced transcription. TOP2B peaks were found across the whole genome, 50% of the peaks fell either within a gene or within 5 kb of a transcription start site. TOP2B peaks coincident with gene promoters were less frequently associated with epigenetic features marking active promoters in estradiol treated than in untreated cells. Significantly enriched transcription factor motifs within the DNA sequences underlying the peaks were identified. These included SP1, KLF4, TFAP2A, MYF, REST, CTCF, ESR1 and ESR2. Gene ontology analysis of genes associated with TOP2B peaks found neuronal development terms including axonogenesis and axon guidance were significantly enriched. In the absence of functional TOP2B there are errors in axon guidance in the zebrafish eye. Specific heparin sulphate structures are involved in retinal axon targeting. The glycosaminoglycan biosynthesis–heparin sulphate/heparin pathway is significantly enriched in the TOP2B gene ontology analysis, suggesting changes in this pathway in the absence of TOP2B may cause the axon guidance faults. PMID:26459242

  8. Enhanced 1520 nm photoluminescence from Er3+ ions in di-erbium-carbide metallofullerenes (Er2C2)@C82 (isomers I, II, and III).

    PubMed

    Ito, Yasuhiro; Okazaki, Toshiya; Okubo, Shingo; Akachi, Masahiro; Ohno, Yutaka; Mizutani, Takashi; Nakamura, Tetsuya; Kitaura, Ryo; Sugai, Toshiki; Shinohara, Hisanori

    2007-12-01

    Di-erbium and di-erbium-carbide endohedral metallofullerenes with a C(82) cage such as Er(2)@C(82) (isomers I, II, and III) and (Er(2)C(2))@C(82) (isomers I, II, and III) have been synthesized and chromatographically isolated (99%). The structures of Er(2)@C(82) (I, II, III) and (Er(2)C(2))@C(82) (I, II, III) metallofullerenes are characterized by comparison with the UV-vis-NIR absorption spectra of (Y(2)C(2))@C(82) (I, II, III), where molecular symmetries of the structures are determined to be C(s), C(2v) and C(3v), respectively. Furthermore, enhanced near-infrared photoluminescence (PL) at 1520 nm from Er(3+) ions in Er(2)@C(82) (I, III) and (Er(2)C(2))@C(82) (I, III) have been observed at room temperature. The PL intensities have been shown to depend on the symmetry of the C(82) cage. In particular, the PL intensity of (Er(2)C(2))@C(82) (III) has been the strongest among the isomers of Er(2)@C(82) and (Er(2)C(2))@C(82). Optical measurements indicate that the PL properties of Er(2)@C(82) (I, II, III) and (Er(2)C(2))@C(82) (I, II, III) correlate strongly with the absorbance at 1520 nm and the HOMO-LUMO energy gap of the C(82) cage.

  9. SH2B1 regulation of energy balance, body weight, and glucose metabolism

    PubMed Central

    Rui, Liangyou

    2014-01-01

    The Src homology 2B (SH2B) family members (SH2B1, SH2B2 and SH2B3) are adaptor signaling proteins containing characteristic SH2 and PH domains. SH2B1 (also called SH2-B and PSM) and SH2B2 (also called APS) are able to form homo- or hetero-dimers via their N-terminal dimerization domains. Their C-terminal SH2 domains bind to tyrosyl phosphorylated proteins, including Janus kinase 2 (JAK2), TrkA, insulin receptors, insulin-like growth factor-1 receptors, insulin receptor substrate-1 (IRS1), and IRS2. SH2B1 enhances leptin signaling by both stimulating JAK2 activity and assembling a JAK2/IRS1/2 signaling complex. SH2B1 promotes insulin signaling by both enhancing insulin receptor catalytic activity and protecting against dephosphorylation of IRS proteins. Accordingly, genetic deletion of SH2B1 results in severe leptin resistance, insulin resistance, hyperphagia, obesity, and type 2 diabetes in mice. Neuron-specific overexpression of SH2B1β transgenes protects against diet-induced obesity and insulin resistance. SH2B1 in pancreatic β cells promotes β cell expansion and insulin secretion to counteract insulin resistance in obesity. Moreover, numerous SH2B1 mutations are genetically linked to leptin resistance, insulin resistance, obesity, and type 2 diabetes in humans. Unlike SH2B1, SH2B2 and SH2B3 are not required for the maintenance of normal energy and glucose homeostasis. The metabolic function of the SH2B family is conserved from insects to humans. PMID:25126397

  10. Thermoelectric performance of functionalized Sc2C MXenes

    NASA Astrophysics Data System (ADS)

    Kumar, S.; Schwingenschlögl, U.

    2016-07-01

    Functionalization of the MXene Sc2C , which has the rare property to realize semiconducting states for various functionalizations including O, F, and OH, is studied with respect to the electronic and thermal behavior. The lowest lattice thermal conductivity is obtained for OH functionalization and an additional 30% decrease can be achieved by confining the phonon mean free path to 100 nm. Despite a relatively low Seebeck coefficient, Sc2C (OH) 2 is a candidate for intermediate-temperature thermoelectric applications due to compensation by a high electrical conductivity and very low lattice thermal conductivity.

  11. Effects of the 5-HT2B receptor agonist, BW 723C86, on three rat models of anxiety.

    PubMed

    Kennett, G A; Bright, F; Trail, B; Baxter, G S; Blackburn, T P

    1996-04-01

    1. BW 723C86 (3 and 10 mg kg-1, s.c. 30 min pretest), a 5-HT2B receptor agonist, increased total interaction, but not locomotion in a rat social interaction test, a profile consistent with anxiolysis. 2. The effect of BW 723C86 in the social interaction test is likely to be 5-HT2B receptor-mediated as it was prevented by pretreatment with the 5-HT2C/2B receptor antagonist, SB 200646A, (1 and 2 mg kg-1, p.o., 1 h pretest) which did not affect basal levels of social interaction at the doses used. 3. An anxiolytic-like action was also observed in the rat Geller-Seifter conflict test, where BW 723C86 (0.5-50 mg kg-1, s.c. 30 min pretest) modestly, but significantly increased punished, but not unpublished responding. 4. In a rat 5 min elevated x-maze test, BW 723C86 (1-10 mg kg-1, s.c.) had no significant effect. 5. The maximal anxiolytic-like effect of BW 723C86 approached that of the benzodiazepine anxiolytic, chloradiazepoxide (5 mg kg-1, s.c. 30 min pretest) in the social interaction test, but was markedly less in the Geller-Siefter test. The effect of BW 723C86 was also clearly less than chlordiazepoxide in the elevated x-maze procedure where it had no significant effect. 6. In conclusion, BW 723C86 exerted an appreciable anxiolytic-like profile in a rat social interaction test, but had a weaker effect in the Geller-Siefter and was ineffective in the elevated x-maze test used. These effects are likely to be 5-HT2B receptor-mediated. PMID:8730737

  12. On unusual temperature dependence of the upper critical field in YNi 2- xFe xB 2C

    NASA Astrophysics Data System (ADS)

    Kumary, T. Geetha; Kalavathi, S.; Valsakumar, M. C.; Hariharan, Y.; Radhakrishnan, T. S.

    1997-02-01

    Measurement of upper critica field in YNi 2- xFe xB 2C is reported for x = 0, 0.05, 0.10, and 0.15. An anomalous positive curvature is observed for a range of temperatures close to Tc, for all x. As x is increased, the temperature interval over which the curvature in Hc2( T) is positive, is reduced and the system shows a tendency to go to the usual behaviour exhibited by conventional low temperature superconductors. Most of the theories based on a Fermi liquid normal state seem to be inadequate to understand this anomalous behaviour. It is speculated that this anomalous behaviour of Hc2( T) signifies the presence of strong correlations in the pristine YNi 2B 2C and that strong correlation effects become less and less important upon substitution of Ni with Fe.

  13. Natural releases from contaminated groundwater, Example Reference Biosphere 2B.

    PubMed

    Simón, I; Naito, M; Thorne, M C; Walke, R

    2005-01-01

    Safety assessment is a tool which, by means of an iterative procedure, allows the evaluation of the performance of a disposal system and its potential impact on human health and the environment. Radionuclides from a deep geological disposal facility may not reach the surface environment until many tens of thousands of years after closure of the facility. The BIOMASS Programme on BIOsphere Modelling and ASSessment developed Examples of "Reference Biospheres" to illustrate the use of the methodology and to demonstrate how biosphere models can be developed and justified as being fit for purpose. The practical examples are also intended to be useful in their own right. The Example Reference Biosphere 2B presented here involves the consideration of alternative types of geosphere-biosphere interfaces and calculation of doses to members of hypothetical exposure groups arising from a wide range of exposure pathways within agricultural and semi-natural environments, but without allowing for evolution of the corresponding biosphere system. The example presented can be used as a generic analysis in some situations although it was developed around a relatively specific conceptual model. It should be a useful practical example, but the above numerical results are not intended to be understood as prescribed biosphere 'conversion factors'.

  14. BRI2 (ITM2b) Inhibits Aβ Deposition in Vivo

    PubMed Central

    Kim, Jungsu; Miller, Victor M.; Levites, Yona; West, Karen Jansen; Zwizinski, Craig W.; Moore, Brenda D.; Troendle, Fredrick J.; Bann, Maralyssa; Verbeeck, Christophe; Price, Robert W.; Smithson, Lisa; Sonoda, Leilani; Wagg, Kayleigh; Rangachari, Vijayaraghavan; Zou, Fanggeng; Younkin, Steven G.; Graff-Radford, Neill; Dickson, Dennis; Rosenberry, Terrone; Golde, Todd E.

    2008-01-01

    Analyses of the biologic effects of mutations in the BRI2 (ITM2b) and the amyloid β precursor protein (APP) genes support the hypothesis that cerebral accumulation of amyloidogenic peptides in familial British and familial Danish dementias and Alzheimer’s disease (AD) is associated with neurodegeneration. We have used somatic brain transgenic technology to express the BRI2 and BRI2-Aβ1-40 transgenes in amyloid β protein precursor (APP) mouse models. Expression of BRI2-Aβ1-40 mimics the suppressive effect previously observed using conventional transgenic methods, further validating the somatic brain transgenic methodology. Unexpectedly, we also find that expression of wild type human BRI2 reduces cerebral Aβ deposition in an AD mouse model. Additional data indicate that the 23 amino acid peptide, Bri23, released from BRI2 by normal processing is present in human cerebrospinal fluid (CSF), inhibits Aβ aggregation in vitro, and mediates its anti-amyloidogenic effect in vivo. These studies demonstrate that BRI2 is a novel mediator of Aβ deposition in vivo. PMID:18524908

  15. Molecular characterization of an. alpha. sub 2B -adrenergic receptor

    SciTech Connect

    Harrison, J.K.; Dewan Zeng; D'Angelo, D.D.; Tucker, A.L.; Zhihong Lu; Barber, C.M.; Lynch, K.R. )

    1990-02-26

    {alpha}{sub 2}-Adrenergic receptors comprise a heterogeneous population based on pharmacologic and molecular evidence. The authors have isolated a cDNA clone (pRNG{alpha}2) encoding a previously undescribed third subtype of an {alpha}{sub 2}-adrenergic receptor from a rat kidney cDNA library. The library was screened with an oligonucleotide encoding a highly conserved region found in all biogenic amine receptors described to date. The deduced amino acid sequence displays many features of G-protein coupled receptors with exception of the absence of the consensus N-linked glycosylation site at the amino terminus. Membranes prepared from COS-1 cells transfected with pRNG{alpha}2 display high affinity and saturable binding to {sup 3}H-rauwolscine (K{sub d}=2 nM).Competition curve data analysis shows that pRNG{alpha}2 protein binds to a variety of adrenergic drugs with the following rank order of potency: yohimbine {ge} cholorpromazine > prazosin {ge} clonidine > norepinephrine {ge} oxymetazoline. pRNG{alpha}2 RNA accumulates in both adult rat kidney and rat neonatal lung (predominant species is 4.0 kb). They conclude that pRNG{alpha}2 likely represents a cDNA for the {alpha}{sub 2B}-adrenergic receptor.

  16. Remission of liver fibrosis by interferon-alpha 2b.

    PubMed

    Moreno, M G; Muriel, P

    1995-08-01

    Fibrosis is a dynamic process associated with the continuous deposition and resorption of connective tissue, mainly collagen. Therapeutic strategies are emerging by which this dynamic process can be modulated. Since interferons are known to inhibit collagen production, the aim of this study was to investigate if the administration of interferon-alpha 2b (IFN-alpha) can restore the normal hepatic content of collagen in rats with established fibrosis. Fibrosis was induced by prolonged bile duct ligation. IFN-alpha (100,000 IU/rat/day; s.c.) was administered to fibrotic rats for 15 days. Bile duct ligation increased liver collagen content 6-fold. In addition, serum and liver markers of hepatic injury increased significantly; liver histology showed an increase in collagen deposition, and the normal architecture was lost, with large zones of necrosis being observed frequently. IFN-alpha administration reversed to normal the values of all the biochemical markers measured and restored the normal architecture of the liver. Our results demonstrated that IFN-alpha is useful in reversing fibrosis and liver damage induced by biliary obstruction in the rat. However, further investigations are required to evaluate the therapeutic relevance of interferons on non-viral fibrosis and cholestasis. PMID:7646558

  17. Molecular evolution of the mammalian alpha 2B adrenergic receptor.

    PubMed

    Madsen, Ole; Willemsen, Diederik; Ursing, Björn M; Arnason, Ulfur; de Jong, Wilfried W

    2002-12-01

    The alpha 2B adrenergic receptor (A2AB) is a heptahelical G protein-coupled receptor for catecholamines. We compared the almost complete coding region (about 1,175 bp) of the A2AB gene from 48 mammalian species, including eight newly determined sequences, representing all the 18 eutherian and two marsupial orders. Comparison of the encoded proteins reveals that residues thought to be involved in agonist binding are highly conserved, as are the regions playing a role in G protein-coupling. The three extracellular loops are generally more variable than the transmembrane domains and two of the intracellular loops, indicating a lower functional constraint. However, the greatest variation is observed in the very long, third intracellular loop, where only a few residues and a polyglutamyl tract are preserved. Although this polyglutamyl domain displays a great variation in length, its presence in all described A2ABs confirms its proposed role in agonist-dependent phosphorylation of the third intracellular loop. Phylogenetic analyses of the A2AB data set, including Bayesian methods, recognized the superordinal clades Afrotheria, Laurasiatheria, and Euarchontoglires, in agreement with recent molecular evidence, albeit with lower support. Within Afrotheria, A2AB strongly supports the paenungulate clade and the association of the continental African otter shrew with Malagasy tenrecs. Among Laurasiatheria, A2AB confirms the nesting of whales within the artiodactyls, as a sister group to hippopotamus. Within the Euarchontoglires, there is constant support for rodent monophyly. PMID:12446807

  18. Upregulation of UGT2B4 Expression by 3′-Phosphoadenosine-5′-Phosphosulfate Synthase Knockdown: Implications for Coordinated Control of Bile Acid Conjugation

    PubMed Central

    Barrett, Kathleen G.; Fang, Hailin; Cukovic, Daniela; Dombkowski, Alan A.; Kocarek, Thomas A.

    2015-01-01

    During cholestasis, the bile acid–conjugating enzymes, SULT2A1 and UGT2B4, work in concert to prevent the accumulation of toxic bile acids. To understand the impact of sulfotransferase deficiency on human hepatic gene expression, we knocked down 3′-phosphoadenosine-5′-phosphosulfate synthases (PAPSS) 1 and 2, which catalyze synthesis of the obligate sulfotransferase cofactor, in HepG2 cells. PAPSS knockdown caused no change in SULT2A1 expression; however, UGT2B4 expression increased markedly (∼41-fold increase in UGT2B4 mRNA content). Knockdown of SULT2A1 in HepG2 cells also increased UGT2B4 expression. To investigate the underlying mechanism, we transfected PAPSS-deficient HepG2 cells with a luciferase reporter plasmid containing ∼2 Kb of the UGT2B4 5′-flanking region, which included a response element for the bile acid–sensing nuclear receptor, farnesoid X receptor (FXR). FXR activation or overexpression increased UGT2B4 promoter activity; however, knocking down FXR or mutating or deleting the FXR response element did not significantly decrease UGT2B4 promoter activity. Further evaluation of the UGT2B4 5′-flanking region indicated the presence of distal regulatory elements between nucleotides −10090 and −10037 that negatively and positively regulated UGT2B4 transcription. Pulse-chase analysis showed that increased UGT2B4 expression in PAPSS-deficient cells was attributable to both increased mRNA synthesis and stability. Transfection analysis demonstrated that the UGT2B4 3′-untranslated region decreased luciferase reporter expression less in PAPSS-deficient cells than in control cells. These data indicate that knocking down PAPSS increases UGT2B4 transcription and mRNA stability as a compensatory response to the loss of SULT2A1 activity, presumably to maintain bile acid–conjugating activity. PMID:25948711

  19. The serotonin 2C receptor potently modulates the head-twitch response in mice induced by a phenethylamine hallucinogen

    PubMed Central

    Canal, Clinton E.; Olaghere da Silva, Uade B.; Gresch, Paul J.; Watt, Erin E.; Sanders-Bush, Elaine

    2010-01-01

    Rationale Hallucinogenic serotonin 2A (5-HT2A) receptor partial agonists, such as (±)-1-(2,5-dimethoxy-4-iodo-phenyl)-2-aminopropane hydrochloride (DOI), induce a frontal cortex-dependent head-twitch response (HTR) in rodents, a behavioral proxy of a hallucinogenic response that is blocked by 5-HT2A receptor antagonists. In addition to 5-HT2A receptors, DOI and most other serotonin-like hallucinogens have high affinity and potency as partial agonists at 5-HT2C receptors. Objectives We tested for involvement of 5-HT2C receptors in the HTR induced by DOI. Results Comparison of 5-HT2C receptor knockout and wild-type littermates revealed an approximately 50% reduction in DOI-induced HTR in knockout mice. Also, pretreatment with either the 5-HT2C receptor antagonist SB206553 or SB242084 eradicated a twofold difference in DOI-induced HTR between the standard inbred mouse strains C57BL/6J and DBA/2J, and decreased the DOI-induced HTR by at least 50% in both strains. None of several measures of 5-HT2A receptors in frontal cortex explained the strain difference, including 5-HT2A receptor density, Gαq or Gαi/o protein levels, phospholipase C activity, or DOI-induced expression of Egr1 and Egr2. 5-HT2C receptor density in the brains of C57BL/6J and DBA/2J was also equivalent, suggesting that 5-HT2C receptor-mediated intracellular signaling or other physiological modulators of the HTR may explain the strain difference in response to DOI. Conclusions We conclude that the HTR to DOI in mice is strongly modulated by 5-HT2C receptor activity. This novel finding invites reassessment of hallucinogenic mechanisms involving 5-HT2 receptors. PMID:20165943

  20. Characterization of the Lipid Binding Properties of Otoferlin Reveals Specific Interactions between PI(4,5)P2 and the C2C and C2F Domains

    PubMed Central

    2015-01-01

    Otoferlin is a transmembrane protein consisting of six C2 domains, proposed to act as a calcium sensor for exocytosis. Although otoferlin is believed to bind calcium and lipids, the lipid specificity and identity of the calcium binding domains are controversial. Further, it is currently unclear whether the calcium binding affinity of otoferlin quantitatively matches the maximal intracellular presynaptic calcium concentrations of ∼30–50 μM known to elicit exocytosis. To characterize the calcium and lipid binding properties of otoferlin, we used isothermal titration calorimetry (ITC), liposome sedimentation assays, and fluorescence spectroscopy. Analysis of ITC data indicates that with the exception of the C2A domain, the C2 domains of otoferlin bind multiple calcium ions with moderate (Kd = 25–95 μM) and low affinities (Kd = 400–700 μM) in solution. However, in the presence of liposomes, the calcium sensitivity of the domains increased by up to 10-fold. It was also determined that calcium enhanced liposome binding for domains C2B–C2E, whereas the C2F domain bound liposomes in a calcium-independent manner. Mutations that abrogate calcium binding in C2F do not disrupt liposome binding, supporting the conclusion that the interaction of the C2F domain with phosphatidylserine is calcium-independent. Further, domains C2C and C2F, not domains C2A, C2B, C2D, and C2E, bound phosphatidylinositol 4,5-bisphosphate 1,2-dioleoyl-sn-glycero-3-phospho(1′-myoinositol-4′,5′-bisphosphate) [PI(4,5)P2], which preferentially steered them toward liposomes harboring PI(4,5)P2. Remarkably, lysine mutations L478A and L480A in C2C selectively weaken the PI(4,5)P2 interaction while leaving phosphatidylserine binding unaffected. Finally, shifts in the emission spectra of an environmentally sensitive fluorescent unnatural amino acid indicate that the calcium binding loops of the C2F domain directly interact with the lipid bilayer of negatively charged liposomes in a calcium

  1. E-2C Loads Calibration in DFRC Flight Loads Lab

    NASA Technical Reports Server (NTRS)

    Schuster, Lawrence S.

    2008-01-01

    Objectives: a) Safely and efficiently perform structural load tests on NAVAIR E-2C aircraft to calibrate strain gage instrumentation installed by NAVAIR; b) Collect load test data and derive loads equations for use in NAVAIR flight tests; and c) Assist flight test team with use of loads equations measurements at PAX River.

  2. Genome Sequence of Enterotoxigenic Escherichia coli Strain B2C.

    PubMed

    Madhavan, T P Vipin; Steen, Jason A; Hugenholtz, Philip; Sakellaris, Harry

    2014-04-10

    Enterotoxigenic Escherichia coli (ETEC) is a major cause of diarrheal disease around the globe, causing an estimated 380,000 deaths annually. The disease is caused by a wide variety of strains. Here, we report the genome sequence of ETEC strain B2C, which was isolated from an American soldier in Vietnam.

  3. Convenient syntheses and transformations of 2-C-malonyl carbohydrates.

    PubMed

    Yin, Jian; Sommermann, Thomas; Linker, Torsten

    2007-01-01

    2-C-malonyl carbohydrates were synthesized in only few steps and high yields by radical additions of malonates to glycals. For the first time, the undesired formation of nitrates was completely suppressed with anhydrous cerium ammonium nitrate (CAN) as oxidizing agent. A coherent explanation for the high stereoselectivities of the additions to gluco-configured glycals was provided by variation of the substituents in the 3-position. We established steric effects for the face selectivity, and electronic effects strongly influence the reactivity of the double bonds. The scope and limitation of transition-metal-mediated radical reactions in the synthesis of 2-C-branched carbohydrates was thoroughly investigated. Thus, unsaturated disaccharides and benzyl-protected glycals were used as substrates for the first time. Finally, the 2-C-malonyl carbohydrates were transformed into various products by decarboxylation, saponification and reduction, which afforded interesting precursors for C-disaccharides. In this paper we describe the syntheses of more than 40 new 2-C-analogues of carbohydrates, which were isolated in high yields in analytically pure form. Therefore, the transition-metal-mediated radical addition of malonates to glycals offers a simple and convenient entry to such important carbohydrate derivatives.

  4. High-throughput screening assays for the assessment of CYP2C9*1, CYP2C9*2, and CYP2C9*3 metabolism using fluorogenic Vivid substrates.

    PubMed

    Marks, Bryan D; Thompson, David V; Goossens, Tony A; Trubetskoy, Olga V

    2004-08-01

    CYP2C9 is a genetically polymorphic human cytochrome P450 isozyme involved in the oxidative metabolism of many drugs, including nonsteroidal anti-inflammatory compounds. Individuals genotyped heterozygous or homozygous for CYP2C9 allelic variants have demonstrated altered metabolism of some drugs primarily metabolized by CYP2C9. The ability to expand screening of CYP2C9 allelic variants to a larger set of drugs and pharmaceutical agents would contribute to a better understanding of the significance of CYP2C9 polymorphisms in the population and to predictions of possible outcomes. The authors report the development of an in vitro fluorescence-based assay employing recombinant CYP2C9 variants (CYP2C9*1, CYP2C9*2, and CYP2C9*3) and fluorogenic Vivid(R) CYP2C9 substrates to explore the effects of CYP2C9 polymorphisms on drug metabolism, using drugs primarily metabolized by CYP2C9. Several chemically diverse fluorogenic substrates (Vivid(R) CYP2C9 blue, green, and red substrates) were used as prototypic probes to obtain in vitro CYP2C9 metabolic rates and kinetic parameters, such as apparent K(m), V(max), and V(max)/K(m) ratios for each allelic variant. In addition, a diverse panel of drugs was screened as assay modifiers with CYP2C9*1, CYP2C9*2, CYP2C9*3, and the fluorogenic Vivid(R) CYP2C9 substrates. The inhibitory potential of this large group of chemically diverse drugs and compounds has been assessed on the basis of their ability to compete with Vivid(R) CYP2C9 substrates in fluorescent reporter assays, thus providing a sensitive and quick assessment of polymorphism-dependent changes in CYP2C9 metabolism.

  5. Mechanism for Noncompetitive Inhibition by Novel GluN2C/D N-Methyl-d-aspartate Receptor Subunit-Selective ModulatorsS⃞

    PubMed Central

    Acker, Timothy M.; Yuan, Hongjie; Hansen, Kasper B.; Vance, Katie M.; Ogden, Kevin K.; Jensen, Henrik S.; Burger, Pieter B.; Mullasseril, Praseeda; Snyder, James P.; Liotta, Dennis C.

    2011-01-01

    The compound 4-(5-(4-bromophenyl)-3-(6-methyl-2-oxo-4-phenyl-1,2-dihydroquinolin-3-yl)-4,5-dihydro-1H-pyrazol-1-yl)-4-oxobutanoic acid (DQP-1105) is a representative member of a new class of N-methyl-d-aspartate (NMDA) receptor antagonists. DQP-1105 inhibited GluN2C- and GluN2D-containing receptors with IC50 values that were at least 50-fold lower than those for recombinant GluN2A-, GluN2B-, GluA1-, or GluK2-containing receptors. Inhibition was voltage-independent and could not be surmounted by increasing concentrations of either coagonist, glutamate or glycine, consistent with a noncompetitive mechanism of action. DQP-1105 inhibited single-channel currents in excised outside-out patches without significantly changing mean open time or single-channel conductance, suggesting that DQP inhibits a pregating step without changing the stability of the open pore conformation and thus channel closing rate. Evaluation of DQP-1105 inhibition of chimeric NMDA receptors identified two key residues in the lower lobe of the GluN2 agonist binding domain that control the selectivity of DQP-1105. These data suggest a mechanism for this new class of inhibitors and demonstrate that ligands can access, in a subunit-selective manner, a new site located in the lower, membrane-proximal portion of the agonist-binding domain. PMID:21807990

  6. The impact of adenosine and A(2B) receptors on glucose homoeostasis.

    PubMed

    Rüsing, D; Müller, C E; Verspohl, E J

    2006-12-01

    Adenosine and adenosine receptor antagonists are involved in glucose homoeostasis. The participating receptors are not known, mainly due to a lack of specific agonists and antagonists, but are reasonable targets for anti-diabetic therapy. The stable, albeit nonselective, adenosine analogue NECA (5'-N-ethylcarboxamidoadenosine) (10 microM) reduced glucose-stimulated insulin release from INS-1 cells. This was mimicked by A(1)-(CHA), A(2A)-(CGS-21680) and A(3)-receptor agonists (Cl-IB-MECA). Two newly synthesized A(2B)-receptor antagonists, PSB-53 and PSB-1115, counteracted the inhibitory effect of NECA. These in-vitro effects were mirrored by in-vivo data with respect to CHA, CGS and Cl-IB-MECA. Distinct concentrations of either PSB-53 or PSB-1115 reversed the decrease in plasma insulin induced by NECA. This was not mimicked by a corresponding change in blood glucose. The effect of PSB-1115 was also obvious in diabetic GotoKakizaki rats: plasma insulin was increased whereas blood glucose was unchanged. During most experiments the effects on blood glucose were not impressive probably because of the physiologically necessary homoeostasis. The adenosine levels were not different in normal Wistar rats and in diabetic GotoKakzaki rats. Altogether the A(2B)-receptor antagonists showed an anti-diabetic potential mainly by increasing plasma insulin levels under conditions when the adenosine tonus was elevated in-vivo and increased insulin release in-vitro.

  7. Phagocytosis and solubilization of fixed cells by metastatic hamster embryo fibroblasts, Nil2C2

    SciTech Connect

    Sakiyama, H.; Nishino, Y.; Nishimura, K.; Noda, Y.; Otsu, H.

    1984-05-01

    When Nil2C2, a metastatic clone derived from hamster embryo fibroblasts (Nil), was inoculated over (/sup 3/H)leucine-labeled fixed cells, Nil2C2 cells solubilized and phagocytosed fixed cells, and the radioactivity was released into the culture medium as trichloroacetic acid-soluble fragments. The solubilization of fixed cells was dependent on both the time of incubation of living cells with fixed cells and the number of living cells inoculated. Nil2C2 cells were shown by autoradiographic and electron microscopic studies to peel off fixed cells and ingest them as large fragments. The solubilization of fixed cells was significantly decreased when plasminogen was depleted from the culture medium. Protease inhibitors such as leupeptin, epsilon-aminocaproic acid, and soybean trypsin inhibitor partially inhibited the proteolysis and phagocytosis of Nil2C2 cells. Mouse peritoneal macrophages activated by Salmonella typhimurium solubilized fixed cells after the addition of 12-O-tetradecanoylphorbol-13-acetate. However, they did not phagocytose fixed cells as large fragments.

  8. Beyond the exchange--the future of B2B.

    PubMed

    Wise, R; Morrison, D

    2000-01-01

    Using the Internet to facilitate business-to-business commerce promises many benefits, such as dramatic cost reductions and greater access to buyers and sellers. Yet little is known about how B2B e-commerce will evolve. The authors argue that changes in the financial services industry over the past two decades provide important clues. Exchanges, they say, are not the primary source of value in information-intensive markets; value tends to accumulate among a diverse group of specialists that focus on such tasks as packaging, standard setting, arbitrage, and information management. Because scale and liquidity are vitally important to efficient trading, today's exchanges will consolidate into a relatively small set of mega-exchanges. Originators will handle the origination and aggregation of complex transactions before sending them on to mega-exchanges for execution. E-speculators, seeking to capitalize on an abundance of market information, will tend to concentrate where relatively standardized products can be transferred easily among a large group of buyers. In many markets, a handful of independent solution providers with well-known brand names and solid reputations will thrive alongside mega-exchanges. Sell-side asset exchanges will create the networks and provide the tools to allow suppliers to trade orders among themselves, sometimes after initial transactions with customers are made on the mega-exchanges. For many companies, traditional skills in such areas as product development, manufacturing, and marketing may become relatively less important, while the ability to understand and capitalize on market dynamics may become considerably more important. PMID:11184979

  9. The resurgence of A2B adenosine receptor signaling

    PubMed Central

    Aherne, Carol M.; Kewley, Emily M.; Eltzschig, Holger K.

    2010-01-01

    Since its discovery as a low-affinity adenosine receptor (AR), the A2B receptor (A2BAR), has proven enigmatic in its function. The previous discovery of the A2AAR, which shares many similarities with the A2BAR but demonstrates significantly greater affinity for its endogenous ligand, led to the original perception that the A2BAR was not of substantial physiologic relevance. In addition, lack of specific pharmacological agents targeting the A2BAR made its initial characterization challenging. However, the importance of this receptor was reconsidered when it was observed that the A2BAR is highly transcriptionally regulated by factors implicated in inflammatory hypoxia. Moreover, the notion that during ischemia or inflammation extracellular adenosine is dramatically elevated to levels sufficient for A2BAR activation, indicated that A2BAR signaling may be important to dampen inflammation particularly during tissue hypoxia. In addition, the recent advent of techniques for murine genetic manipulation along with development of pharmacological agents with enhanced A2BAR specificity has provided invaluable tools for focused studies on the explicit role of A2BAR signaling in different disease models. Currently, studies performed with combined genetic and pharmacological approaches have demonstrated that A2BAR signaling plays a tissue protective role in many models of acute diseases e.g. myocardial ischemia, or acute lung injury. These studies indicate that the A2BAR is expressed on a wide variety of cell types and exerts tissue/cell specific effects. This is an important consideration for future studies where tissue or cell type specific targeting of the A2BAR may be used as therapeutic approach. PMID:20546702

  10. Maintenance therapy with interferon alfa 2b in Hodgkin's disease.

    PubMed

    Avilés, A; Díaz-Maqueo, J C; Talavera, A; Nambo, M J; García, E L

    1998-08-01

    We performed a randomized clinical trial to assess the efficacy and toxicity of interferon alfa 2b (IFN) as maintenance therapy in patients with advanced Hodgkin's disease in complete remission (CR) after conventional chemotherapy. One hundred and thirty-five patients (stage IIIB-IV B) were initially treated with EBVD (epirubicin, bleomycin, vinblastine, dacarbazine). IF CR was achieved they were randomly assigned to receive either maintenance therapy with IFN 5.0 MU three times a week for one year or no further treatment (control group). Clinical and laboratory characteristics at diagnosis were quite similar in both groups. After a median follow-up of 74.3 months (range 49 to 108), 61 out of 68 patients (91%; 95% confidence interval (CI): 76% to 97%) remain in first complete remission in the IFN-treated group compared to 38 out of 67 (58%; 95% CI: 49% to 71%) in the control group (p<.01). Overall survival was also better in the IFN treated group: 62 patients (92%; 95% CI: 82% to 97%) are alive free of disease at 7-years compared to 40 patients (67%, 95%: 55% to 76%) in the control group (p<.01). Toxicity secondary to IFN administration was mild and no dose modification was necessary during treatment. All patients received the planned dose of IFN. This was not an intent-to treat analysis. IFN administration as maintenance therapy was appears to be the only cause of improvement in outcome in these patients. We feel that IFN should be considered as maintenance therapy in patients with advanced Hodgkin's disease because this treatment improves the final outcome without the excessive toxicities of more aggressive therapeutic approaches such as bone marrow transplantation during first CR. We hope that IFN will be considered in future randomized clinical trials in order to define it's role in the treatment of Hodgkin's disease. PMID:9711927

  11. Functional characterization of cytochromes P450 2B from the desert woodrat Neotoma lepida

    PubMed Central

    Wilderman, P. Ross; Jang, Hyun-Hee; Malenke, Jael R.; Salib, Mariam; Angermeier, Elizabeth; Lamime, Sonia; Dearing, M. Denise; Halpert, James R.

    2014-01-01

    Mammalian detoxification processes have been the focus of intense research, but little is known about how wild herbivores process plant secondary compounds, many of which have medicinal value or are drugs. cDNA sequences that code for three enzymes of the cytochrome P450 (CYP) 2B subfamily, here termed 2B35, 2B36, and 2B37 have been recently identified from a wild rodent, the desert woodrat (Malenke et al., 2012). Two variant clones of each enzyme were engineered to increase protein solubility and to facilitate purification, as reported for CYP2B enzymes from multiple species. When expressed in E. coli each of the woodrat proteins gave the characteristic maximum at 450 nm in a reduced carbon monoxide difference spectrum but generally expressed at lower levels than rat CYP2B1. Two enzymes, 2B36 and 2B37, showed dealkylation activity with the model substrates 7-ethoxy-4-(trifluoromethyl)coumarin and 7-benzyloxyresorufin, whereas 2B35 was inactive. Binding of the monoterpene (+)-α-pinene produced a Type I shift in the absorbance spectrum of each enzyme. Mutation of 2B37 at residues 114, 262, or 480, key residues governing ligand interactions with other CYP2B enzymes, did not significantly change expression levels or produce the expected functional changes. In summary, two catalytic and one ligand-binding assay are sufficient to distinguish among CYP2B35, 2B36, and 2B37. Differences in functional profiles between 2B36 and 2B37 are partially explained by changes in substrate recognition site residue 114, but not 480. The results advance our understanding of the mechanisms of detoxification in wild mammalian herbivores and highlight the complexity of this system. PMID:24361551

  12. Archaeal aIF2B interacts with eukaryotic translation initiation factors eIF2α and eIF2Bα: implications for aIF2B function and eIF2B regulation

    PubMed Central

    Dev, Kamal; Santangelo, Thomas J.; Rothenburg, Stefan; Neculai, Dante; Dey, Madhusudan; Sicheri, Frank; Dever, Thomas E.; Reeve, John N.; Hinnebusch, Alan G.

    2009-01-01

    Translation initiation is down-regulated in eukaryotes by phosphorylation of the α subunit of eIF2, which inhibits its guanine nucleotide exchange factor eIF2B. The N-terminal S1 domain of phosphorylated eIF2α interacts with a subcomplex of eIF2B formed by the three regulatory subunits, α/GCN3, β/GCD7, and δ/GCD2, blocking the GDP-GTP exchange activity of the catalytic ε-subunit of eIF2B. These regulatory subunits have related sequences and also have sequences in common with many archaeal proteins, some of which are involved in methionine salvage and CO2 fixation. Our sequence analyses predicted however that members of one phylogenetically distinct and coherent group of these archaeal proteins (designated aIF2Bs) are functional homologues of the α, β and δ subunits of eIF2B. Three of these proteins, from different Archaea, have been shown to bind in vitro to the α subunit of the archaeal aIF2 from the cognate Archaeon. In once case, the aIF2B protein was shown further to bind to the S1 domain of the α subunit of yeast eIF2 in vitro and to interact with eIF2Bα/GCN3 in vivo in yeast. The aIF2B-eIF2α interaction was however independent of eIF2α phosphorylation. Mass spectrometry has identified several proteins that copurify with aIF2B from Thermococcus kodakaraensis and these include aIF2α, a sugar-phosphate nucleotidyltransferase with sequence similarity to eIF2Bε, and several large subunit (50S) ribosomal proteins. Based on this evidence that aIF2B has functions in common with eIF2B, the crystal structure established for an aIF2B was used to construct a model of the eIF2B regulatory subcomplex. In this model, the evolutionarily conserved regions and sites of regulatory mutations in the three eIF2B subunits in yeast are juxtaposed in one continuous binding surface for phosphorylated eIF2α. PMID:19616556

  13. Enhanced tumor trafficking of GD2 chimeric antigen receptor T cells by expression of the chemokine receptor CCR2b.

    PubMed

    Craddock, John A; Lu, An; Bear, Adham; Pule, Martin; Brenner, Malcolm K; Rooney, Cliona M; Foster, Aaron E

    2010-10-01

    For adoptive T-cell therapy to be effective against solid tumors, tumor-specific T cells must be able to migrate to the tumor site. One requirement for efficient migration is that the effector cells express chemokine receptors that match the chemokines produced either by tumor or tumor-associated cells. In this study, we investigated whether the tumor trafficking of activated T cells (ATCs) bearing a chimeric antigen receptor specific for the tumor antigen GD2 (GD2-CAR) could be enhanced by forced coexpression of the chemokine receptor CCR2b, as this receptor directs migration toward CCL2, a chemokine produced by many tumors, including neuroblastoma. Neuroblastoma cell lines (SK-N-SH and SK-N-AS) and primary tumor cells isolated from 6 patients all secreted high levels of CCL2, but GD2-CAR transduced ATCs lacked expression of CCR2 (<5%) and migrated poorly to recombinant CCL2 or tumor supernatants. After retroviral transduction, however, ATCs expressed high levels of CCR2b (>60%) and migrated well in vitro. We expressed firefly luciferase in CCR2b-expressing ATCs and observed improved homing (>10-fold) to CCL2-secreting neuroblastoma compared with CCR2-negative ATCs. As a result, ATCs co-modified with both CCR2b and GD2-CAR had greater antitumor activity in vivo.

  14. Enhanced Tumor Trafficking of GD2 Chimeric Antigen Receptor T Cells by Expression of the Chemokine Receptor CCR2b

    PubMed Central

    Craddock, John A; Lu, An; Bear, Adham; Pule, Martin; Brenner, Malcolm K; Rooney, Cliona M; Foster, Aaron E

    2010-01-01

    For adoptive T cell therapy to be effective against solid tumors, tumor-specific T cells must be able to migrate to the tumor site. One requirement for efficient migration is that the effector cells express chemokine receptors that match the chemokines produced either by tumor or tumor-associated cells. In this study, we investigated whether the tumor trafficking of activated T cells (ATCs) bearing a chimeric antigen receptor specific for the tumor antigen GD2 (GD2-CAR) could be enhanced by forced co-expression of the chemokine receptor CCR2b, since this receptor directs migration towards CCL2, a chemokine produced by many tumors, including neuroblastoma. Neuroblastoma cell lines (SK-N-SH and SK-N-AS) and primary tumor cells isolated from six patients all secreted high levels of CCL2, but GD2-CAR transduced ATCs lacked expression of CCR2 (<5%) and migrated poorly to recombinant CCL2 or tumor supernatants. Following retroviral transduction, however, ATCs expressed high levels of CCR2b (>60%) and migrated well in vitro. We expressed firefly luciferase in CCR2b-expressing ATCs and observed improved homing (>10-fold) to CCL2-secreting neuroblastoma compared to CCR2 negative ATCs. As a result, ATCs co-modified with both CCR2b and GD2-CAR had greater anti-tumor activity in vivo. PMID:20842059

  15. Short communication: predominance of beta-casein (CSN2) C allele in goat breeds reared in Italy.

    PubMed

    Chessa, S; Budelli, E; Chiatti, F; Cito, A M; Bolla, P; Caroli, A

    2005-05-01

    A protocol for the rapid and simultaneous genotyping of A, C, and 0 'CSN2 alleles in goat was developed by single strand conformational polymorphism polymerase chain reaction (SSCP-PCR) technique. Screening the CSN2 variability in 7 goat breeds reared in Italy validated the genotyping test. The SSCP-PCR technique was also suitable for monitoring CSN2 polymorphism. In particular, the discrimination between CSN2*A and CSN2*C is important because the 2 corresponding protein variants cannot be separated by standard typing techniques. The monitoring of CSN2 variability in the goat breeds indicates the predominance of the C allele. In most breeds, CSN2*C occurred with the highest frequency, except in Saanen where CSN2*A and CSN2*C showed similar frequencies. Variant CSN2*C occurred with a frequency of 0.68 (Camosciata), 0.70 (Jonica), 0.71 (Garganica), 0.82 (Maltese), 0.87 (Cilentana), and 0.97 (Orobica). The alignment among the mature CSN2 sequences of different species suggests that CSN2*A is the ancestral allele compared with CSN2*C. Interestingly, the CSN2*A goat variant showed higher frequencies in selected breeds (Saanen and Camosciata).

  16. Trafficking of the NMDAR2B Receptor Subunit Distal Cytoplasmic Tail from Endoplasmic Reticulum to the Synapse

    PubMed Central

    Standley, Steve; Petralia, Ronald S.; Hamilton, Rebecca; Wang, Ya-Xian; Schubert, Manfred

    2012-01-01

    NMDA receptor NR2A/B subunits have PDZ-binding domains on their extreme C-termini that are known to interact with the PSD-95 family and other PDZ proteins. We explore the interactions between PSD-95 family proteins and the NR2A/B cytoplasmic tails, and the consequences of these interactions, from the endoplasmic reticulum (ER) through delivery to the synapse in primary rat hippocampal and cortical cultured neurons. We find that the NR2A/B cytoplasmic tails cluster very early in the secretory pathway and interact serially with SAP102 beginning at the intermediate compartment, and then PSD-95. We further establish that colocalization of the distal C-terminus of NR2B and PSD-95 begins at the trans-Golgi Network (TGN). Formation of NR2B/PSD-95/SAP102 complexes is dependent on the PDZ binding domain of NR2B subunits, but association with SAP102 and PSD-95 plays no distinguishable role in cluster pre-formation or initial targeting to the vicinity of the synapse. Instead the PDZ binding domain plays a role in restricting cell-surface clusters to postsynaptic targets. PMID:22761831

  17. [Medullary thyroid carcinoma in a 10-month-old child with multiple endocrine neoplasia 2B].

    PubMed

    Mathiesen, Jes Sloth; Døssing, Helle; Bender, Lars; Godballe, Christian

    2014-01-27

    In infants at risk of multiple endocrine neoplasia type 2B (MEN2B) the American Thyroid Association recommends genetic testing as soon as possible after birth and that thyroidectomy should be performed in MEN2B RET-mutation positive individuals as soon as possible and if possible within the first year of life. We present a ten-month-old girl with MEN2B who had prophylactic thyroidectomy. The surgical specimen showed medullary thyroid carcinoma. This case emphasizes the need for early diagnosis and prophylactic thyroidectomy in MEN2B patients. PMID:27498810

  18. A 12p13 GRIN2B deletion is associated with developmental delay and macrocephaly.

    PubMed

    Morisada, Naoya; Ioroi, Tomoaki; Taniguchi-Ikeda, Mariko; Juan Ye, Ming; Okamoto, Nobuhiko; Yamamoto, Toshiyuki; Iijima, Kazumoto

    2016-01-01

    N-methyl D-aspartate receptor subtype 2B (GluN2B), encoded by GRIN2B, is one of the components of the N-methyl D-aspartate receptor protein. Aberrations in GRIN2B have been reported to be responsible for various types of neurodevelopmental disorders. We report a Japanese boy with an ~2 Mb interstitial deletion in 12p13 involving the entire GRIN2B gene, who presented with intellectual disability, motor developmental delay and marked macrocephaly. PMID:27656287

  19. A 12p13 GRIN2B deletion is associated with developmental delay and macrocephaly

    PubMed Central

    Morisada, Naoya; Ioroi, Tomoaki; Taniguchi-Ikeda, Mariko; Juan Ye, Ming; Okamoto, Nobuhiko; Yamamoto, Toshiyuki; Iijima, Kazumoto

    2016-01-01

    N-methyl D-aspartate receptor subtype 2B (GluN2B), encoded by GRIN2B, is one of the components of the N-methyl D-aspartate receptor protein. Aberrations in GRIN2B have been reported to be responsible for various types of neurodevelopmental disorders. We report a Japanese boy with an ~2 Mb interstitial deletion in 12p13 involving the entire GRIN2B gene, who presented with intellectual disability, motor developmental delay and marked macrocephaly.

  20. A 12p13 GRIN2B deletion is associated with developmental delay and macrocephaly

    PubMed Central

    Morisada, Naoya; Ioroi, Tomoaki; Taniguchi-Ikeda, Mariko; Juan Ye, Ming; Okamoto, Nobuhiko; Yamamoto, Toshiyuki; Iijima, Kazumoto

    2016-01-01

    N-methyl D-aspartate receptor subtype 2B (GluN2B), encoded by GRIN2B, is one of the components of the N-methyl D-aspartate receptor protein. Aberrations in GRIN2B have been reported to be responsible for various types of neurodevelopmental disorders. We report a Japanese boy with an ~2 Mb interstitial deletion in 12p13 involving the entire GRIN2B gene, who presented with intellectual disability, motor developmental delay and marked macrocephaly. PMID:27656287

  1. High-Resolution Infrared Spectroscopy of Ge_2C_3

    NASA Astrophysics Data System (ADS)

    Thorwirth, S.; Lutter, V.; Schlemmer, S.; Giesen, T. F.; Gauss, J.

    2013-06-01

    Carbon-rich systems are of great importance in diverse areas of research like material science as well as astro- and structural chemistry. Despite this relevance, our knowledge of smaller cluster units is still fragmentary, particularly with respect to investigations at high-spectral resolution in the gas phase. Unequivocal assignment of spectral features to their molecular carriers is critically dependent on predictions from high-level quantum-chemical calculations. In turn, high-resolution studies provide useful information to assess the predictive power of quantum-chemical methods. This is particularly interesting for cluster systems harboring heavy elements for which so far relatively little is known from experiment. With this contribution, we would like to present a recent gas-phase study of a polyatomic germanium-carbon cluster, linear Ge_2C_3 (Ge=C=C=C=Ge), which was previously studied in an Ar matrix. The cluster was produced through laser ablation of germanium-graphite sample rods and observed in a free jet at wavelengths around 5μm. Additionally, quantum-chemical calculations of Ge_2C_3 were performed at the CCSD(T) level of theory. The production and observation of Ge_2C_3 suggests that many more binary clusters should be amenable to high-resolution spectroscopic techniques not only in the infrared but also in the microwave region. D. L. Robbins, C. M. L. Rittby, and W. R. M. Graham, J. Chem. Phys. 114, 3570 (2001).

  2. Postsynaptic density protein 95-regulated NR2B tyrosine phosphorylation and interactions of Fyn with NR2B in levodopa-induced dyskinesia rat models

    PubMed Central

    Ba, Maowen; Kong, Min; Ma, Guozhao

    2015-01-01

    Context Abnormality in interactions between N-methyl-d-aspartate (NMDA) receptor and its signaling molecules occurs in the lesioned striatum in Parkinson’s disease (PD) and levodopa-induced dyskinesia (LID). It was reported that Fyn-mediated NR2B tyrosine phosphorylation, can enhance NMDA receptor function. Postsynaptic density protein 95 (PSD-95), one of the synapse-associated proteins, regulates interactions between receptor and downstream-signaling molecules. In light of the relationship between PSD-95, NR2B, and Fyn kinases, does PSD-95 contribute to the overactivity of NMDA receptor function induced by dopaminergic treatment? To further prove the possibility, the effects of regulating the PSD-95 expression on the augmented NR2B tyrosine phosphorylation and on the interactions of Fyn and NR2B in LID rat models were evaluated. Methods In the present study, parkinsonian rat models were established by injecting 6-hydroxydopamine. Subsequently, valid PD rats were treated with levodopa (50 mg/kg/day with benserazide 12.5 mg/kg/day, twice daily) intraperitoneally for 22 days to create LID rat models. Then, the effect of pretreatment with an intrastriatal injection of the PSD-95mRNA antisense oligonucleotides (PSD-95 ASO) on the rotational response to levodopa challenge was assessed. The effects of pretreatment with an intrastriatal injection of PSD-95 ASO on the augmented NR2B tyrosine phosphorylation and interactions of Fyn with NR2B in the LID rat models were detected by immunoblotting and immunoprecipitation. Results Levodopa administration twice daily for 22 days to parkinsonian rats shortened the rotational duration and increased the peak turning responses. The altered rotational responses were attenuated by PSD-95 ASO pretreatment. Meanwhile, PSD-95 ASO pretreatment decreased the level of PSD-95 protein expression and reduced both the augmented NR2B tyrosine phosphorylation and interactions of Fyn with NR2B triggered during the levodopa administration in the

  3. Homo- and hetero-dimerization of human UDP-glucuronosyltransferase 2B7 (UGT2B7) wild type and its allelic variants affect zidovudine glucuronidation activity.

    PubMed

    Yuan, Lingmin; Qian, Sainan; Xiao, Yongsheng; Sun, Hongying; Zeng, Su

    2015-05-01

    Most human UDP-glucuronosyltransferase (UGT; EC 2.4.1.17) genes contain non-synonymous single nucleotide polymorphisms (nsSNPs) which cause amino acid substitutions. Allelic variants caused by nsSNPs may exhibit absent or reduced enzyme activity. UGT2B7 is one of the most important UGTs that glucuronidates abundant endobiotics and xenobiotics, such as estriol, morphine, and anticancer drugs. Three nsSNPs, UGT2B7*71S (211G>T), UGT2B7*2 (802C>T) and UGT2B7*5 (1192G>A) are observed in the UGT2B7 gene, and they code for allozymes UGT2B7*71S (A71S), UGT2B7*2 (H268Y), and UGT2B7*5 (D398N). UGT2B7 has been observed to form oligomers that affect its enzymatic activity and in this study, we investigated protein-protein interactions among UGT2B7 allozymes wild type (WT), A71S, H268Y and D398N, by performing a systematic quantitative fluorescence resonance energy transfer (FRET) analysis in combination with co-immunoprecipitation assay. Quantitative FRET analysis revealed that UGT2B7 allozymes formed homo- and hetero-dimers and showed distinct features in donor-acceptor distances. Both codon 71 and codon 268 in the N-terminal domain were involved in the dimeric interaction. Co-immunoprecipitation experiments also proved that UGT2B7 allozymes formed stable dimers. The glucuronidation activities of homo- and hetero-dimers were further tested with zidovudine as the substrate. An increase in activity was observed when WT hetero-dimerized with A71S compared with homo-dimers, while both H268Y and D398N impaired the activity of WT and A71S by forming hetero-dimers. In addition, zidovudine glucuronidation activity is associated with FRET distance. These findings provide insights into the consequences of amino acid substitution in UGT2B7 on zidovudine glucuronidation and the association between protein-protein interaction and glucuronidation activity. PMID:25770680

  4. Trypanosoma brucei Co-opts NK Cells to Kill Splenic B2 B Cells.

    PubMed

    Frenkel, Deborah; Zhang, Fengqiu; Guirnalda, Patrick; Haynes, Carole; Bockstal, Viki; Radwanska, Magdalena; Magez, Stefan; Black, Samuel J

    2016-07-01

    After infection with T. brucei AnTat 1.1, C57BL/6 mice lost splenic B2 B cells and lymphoid follicles, developed poor parasite-specific antibody responses, lost weight, became anemic and died with fulminating parasitemia within 35 days. In contrast, infected C57BL/6 mice lacking the cytotoxic granule pore-forming protein perforin (Prf1-/-) retained splenic B2 B cells and lymphoid follicles, developed high-titer antibody responses against many trypanosome polypeptides, rapidly suppressed parasitemia and did not develop anemia or lose weight for at least 60 days. Several lines of evidence show that T. brucei infection-induced splenic B cell depletion results from natural killer (NK) cell-mediated cytotoxicity: i) B2 B cells were depleted from the spleens of infected intact, T cell deficient (TCR-/-) and FcγRIIIa deficient (CD16-/-) C57BL/6 mice excluding a requirement for T cells, NKT cell, or antibody-dependent cell-mediated cytotoxicity; ii) administration of NK1.1 specific IgG2a (mAb PK136) but not irrelevant IgG2a (myeloma M9144) prevented infection-induced B cell depletion consistent with a requirement for NK cells; iii) splenic NK cells but not T cells or NKT cells degranulated in infected C57BL/6 mice co-incident with B cell depletion evidenced by increased surface expression of CD107a; iv) purified NK cells from naïve C57BL/6 mice killed purified splenic B cells from T. brucei infected but not uninfected mice in vitro indicating acquisition of an NK cell activating phenotype by the post-infection B cells; v) adoptively transferred C57BL/6 NK cells prevented infection-induced B cell population growth in infected Prf1-/- mice consistent with in vivo B cell killing; vi) degranulated NK cells in infected mice had altered gene and differentiation antigen expression and lost cytotoxic activity consistent with functional exhaustion, but increased in number as infection progressed indicating continued generation. We conclude that NK cells in T. brucei infected mice

  5. Trypanosoma brucei Co-opts NK Cells to Kill Splenic B2 B Cells

    PubMed Central

    Frenkel, Deborah; Guirnalda, Patrick; Haynes, Carole; Bockstal, Viki; Magez, Stefan; Black, Samuel J.

    2016-01-01

    After infection with T. brucei AnTat 1.1, C57BL/6 mice lost splenic B2 B cells and lymphoid follicles, developed poor parasite-specific antibody responses, lost weight, became anemic and died with fulminating parasitemia within 35 days. In contrast, infected C57BL/6 mice lacking the cytotoxic granule pore-forming protein perforin (Prf1-/-) retained splenic B2 B cells and lymphoid follicles, developed high-titer antibody responses against many trypanosome polypeptides, rapidly suppressed parasitemia and did not develop anemia or lose weight for at least 60 days. Several lines of evidence show that T. brucei infection-induced splenic B cell depletion results from natural killer (NK) cell-mediated cytotoxicity: i) B2 B cells were depleted from the spleens of infected intact, T cell deficient (TCR-/-) and FcγRIIIa deficient (CD16-/-) C57BL/6 mice excluding a requirement for T cells, NKT cell, or antibody-dependent cell-mediated cytotoxicity; ii) administration of NK1.1 specific IgG2a (mAb PK136) but not irrelevant IgG2a (myeloma M9144) prevented infection-induced B cell depletion consistent with a requirement for NK cells; iii) splenic NK cells but not T cells or NKT cells degranulated in infected C57BL/6 mice co-incident with B cell depletion evidenced by increased surface expression of CD107a; iv) purified NK cells from naïve C57BL/6 mice killed purified splenic B cells from T. brucei infected but not uninfected mice in vitro indicating acquisition of an NK cell activating phenotype by the post-infection B cells; v) adoptively transferred C57BL/6 NK cells prevented infection-induced B cell population growth in infected Prf1-/- mice consistent with in vivo B cell killing; vi) degranulated NK cells in infected mice had altered gene and differentiation antigen expression and lost cytotoxic activity consistent with functional exhaustion, but increased in number as infection progressed indicating continued generation. We conclude that NK cells in T. brucei infected mice

  6. Trypanosoma brucei Co-opts NK Cells to Kill Splenic B2 B Cells.

    PubMed

    Frenkel, Deborah; Zhang, Fengqiu; Guirnalda, Patrick; Haynes, Carole; Bockstal, Viki; Radwanska, Magdalena; Magez, Stefan; Black, Samuel J

    2016-07-01

    After infection with T. brucei AnTat 1.1, C57BL/6 mice lost splenic B2 B cells and lymphoid follicles, developed poor parasite-specific antibody responses, lost weight, became anemic and died with fulminating parasitemia within 35 days. In contrast, infected C57BL/6 mice lacking the cytotoxic granule pore-forming protein perforin (Prf1-/-) retained splenic B2 B cells and lymphoid follicles, developed high-titer antibody responses against many trypanosome polypeptides, rapidly suppressed parasitemia and did not develop anemia or lose weight for at least 60 days. Several lines of evidence show that T. brucei infection-induced splenic B cell depletion results from natural killer (NK) cell-mediated cytotoxicity: i) B2 B cells were depleted from the spleens of infected intact, T cell deficient (TCR-/-) and FcγRIIIa deficient (CD16-/-) C57BL/6 mice excluding a requirement for T cells, NKT cell, or antibody-dependent cell-mediated cytotoxicity; ii) administration of NK1.1 specific IgG2a (mAb PK136) but not irrelevant IgG2a (myeloma M9144) prevented infection-induced B cell depletion consistent with a requirement for NK cells; iii) splenic NK cells but not T cells or NKT cells degranulated in infected C57BL/6 mice co-incident with B cell depletion evidenced by increased surface expression of CD107a; iv) purified NK cells from naïve C57BL/6 mice killed purified splenic B cells from T. brucei infected but not uninfected mice in vitro indicating acquisition of an NK cell activating phenotype by the post-infection B cells; v) adoptively transferred C57BL/6 NK cells prevented infection-induced B cell population growth in infected Prf1-/- mice consistent with in vivo B cell killing; vi) degranulated NK cells in infected mice had altered gene and differentiation antigen expression and lost cytotoxic activity consistent with functional exhaustion, but increased in number as infection progressed indicating continued generation. We conclude that NK cells in T. brucei infected mice

  7. Copy Number Variation of UGT 2B Genes in Indian Families Using Whole Genome Scans

    PubMed Central

    Veerappa, Avinash M.; Padakannaya, Prakash; Ramachandra, Nallur B.

    2016-01-01

    Background and Objectives. Uridine diphospho-glucuronosyltransferase 2B (UGT2B) is a family of genes involved in metabolizing steroid hormones and several other xenobiotics. These UGT2B genes are highly polymorphic in nature and have distinct polymorphisms associated with specific regions around the globe. Copy number variations (CNVs) status of UGT2B17 in Indian population is not known and their disease associations have been inconclusive. It was therefore of interest to investigate the CNV profile of UGT2B genes. Methods. We investigated the presence of CNVs in UGT2B genes in 31 members from eight Indian families using Affymetrix Genome-Wide Human SNP Array 6.0 chip. Results. Our data revealed >50% of the study members carried CNVs in UGT2B genes, of which 76% showed deletion polymorphism. CNVs were observed more in UGT2B17 (76.4%) than in UGT2B15 (17.6%). Molecular network and pathway analysis found enrichment related to steroid metabolic process, carboxylesterase activity, and sequence specific DNA binding. Interpretation and Conclusion. We report the presence of UGT2B gene deletion and duplication polymorphisms in Indian families. Network analysis indicates the substitutive role of other possible genes in the UGT activity. The CNVs of UGT2B genes are very common in individuals indicating that the effect is neutral in causing any suspected diseases. PMID:27092269

  8. Copy Number Variation of UGT 2B Genes in Indian Families Using Whole Genome Scans.

    PubMed

    Veerappa, Avinash M; Padakannaya, Prakash; Ramachandra, Nallur B

    2016-01-01

    Background and Objectives. Uridine diphospho-glucuronosyltransferase 2B (UGT2B) is a family of genes involved in metabolizing steroid hormones and several other xenobiotics. These UGT2B genes are highly polymorphic in nature and have distinct polymorphisms associated with specific regions around the globe. Copy number variations (CNVs) status of UGT2B17 in Indian population is not known and their disease associations have been inconclusive. It was therefore of interest to investigate the CNV profile of UGT2B genes. Methods. We investigated the presence of CNVs in UGT2B genes in 31 members from eight Indian families using Affymetrix Genome-Wide Human SNP Array 6.0 chip. Results. Our data revealed >50% of the study members carried CNVs in UGT2B genes, of which 76% showed deletion polymorphism. CNVs were observed more in UGT2B17 (76.4%) than in UGT2B15 (17.6%). Molecular network and pathway analysis found enrichment related to steroid metabolic process, carboxylesterase activity, and sequence specific DNA binding. Interpretation and Conclusion. We report the presence of UGT2B gene deletion and duplication polymorphisms in Indian families. Network analysis indicates the substitutive role of other possible genes in the UGT activity. The CNVs of UGT2B genes are very common in individuals indicating that the effect is neutral in causing any suspected diseases. PMID:27092269

  9. Similar substrate specificity of cynomolgus monkey cytochrome P450 2C19 to reported human P450 2C counterpart enzymes by evaluation of 89 drug clearances.

    PubMed

    Hosaka, Shinya; Murayama, Norie; Satsukawa, Masahiro; Uehara, Shotaro; Shimizu, Makiko; Iwasaki, Kazuhide; Iwano, Shunsuke; Uno, Yasuhiro; Yamazaki, Hiroshi

    2015-12-01

    Cynomolgus monkeys are used widely in preclinical studies as non-human primate species. The amino acid sequence of cynomolgus monkey cytochrome P450 (P450 or CYP) 2C19 is reportedly highly correlated to that of human CYP2C19 (92%) and CYP2C9 (93%). In the present study, 89 commercially available compounds were screened to find potential substrates for cynomolgus monkey CYP2C19. Of 89 drugs, 34 were metabolically depleted by cynomolgus monkey CYP2C19 with relatively high rates. Among them, 30 compounds have been reported as substrates or inhibitors of, either or both, human CYP2C19 and CYP2C9. Several compounds, including loratadine, showed high selectivity to cynomolgus monkey CYP2C19, and all of these have been reported as human CYP2C19 and/or CYP2C9 substrates. In addition, cynomolgus monkey CYP2C19 formed the same loratadine metabolite as human CYP2C19, descarboethoxyloratadine. These results suggest that cynomolgus monkey CYP2C19 is generally similar to human CYP2C19 and CYP2C9 in its substrate recognition functionality.

  10. Mutations of the human interferon alpha-2b (hIFNα-2b) gene in low-dose natural terrestrial ionizing radiation exposed dwellers.

    PubMed

    Shahid, Saman; Mahmood, Nasir; Chaudhry, Muhammad Nawaz; Ahmad, Nauman

    2015-12-01

    Natural terrestrial ionizing radiations emerge from uranium deposits and can impact human tissues by affecting DNA bases which constitute genes. Human interferon alpha-2b (hIFNα-2b) gene synthesizes a protein which exhibits anticancerous, immunomodulatory, anti-proliferative and antiviral properties. This research aimed to find out hIFNα-2b gene mutations for those residents who were chronically exposed to low-dose natural terrestrial ionizing radiations. The gene amplifications was done through PCR technique and gene mutations were identified by bioinformatics in order to conclude as to how mutations identified in hIFNα-2b gene sequences will lead to alterations in the hIFNα-2