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Sample records for prenyl pyrophosphate antigens

  1. Effects of prenyl pyrophosphates on the binding of PKCgamma with RACK1.

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    Chen, Yu-Hsun; Wang, Han-Chung; Lin, Ching-Yu; Chuang, Nin-Nin

    2003-01-01

    Receptors for activated C kinase (RACKs) are a group of PKC binding proteins that have been shown to mediate isoform-selective functions of PKC and to be crucial in the translocation and subsequent functioning of the PKC isoenzymes on activation. RACK1 cDNA from the shrimp Penaeus japonicus was isolated by homology cloning. The hepatopancreas cDNA from this shrimp was found to encode a 318-residue polypeptide whose predicted amino acid sequence shared 91% homology with human G(beta2)-like proteins. Expression of the cDNA of shrimp RACK1 in vitro yielded a 45-kDa polypeptide with positive reactivity toward the monoclonal antibodies against RACK1 of mammals. The shrimp RACK1 was biotinylated and used to compare the effects of geranylgeranyl pyrophosphate and farnesyl pyrophosphate on its binding with PKCgamma in anti-biotin-IgG precipitates. PKCgammas were isolated from shrimp eyes and mouse brains. Both enzyme preparations were able to inhibit taxol-induced tubulin polymerization. Interestingly, when either geranylgeranyl pyrophosphate or farnesyl pyrophosphate was reduced to the submicrogram level, the recruitment activity of RACK1 with purified PKCgamma was found to increase dramatically. The activation is especially significant for RACK1 and PKCgamma from different species. The observation implies that the deprivation of prenyl pyrophosphate might function as a signal for RACK1 to switch the binding from the conventional isoenzymes of PKC (cPKC) to the novel isoenzymes of PKC (nPKC). A hydrophobic binding pocket for geranylgeranyl pyrophosphate in RACK1 is further revealed via prenylation with protein geranylgeranyl transferase I of shrimp P. japonicus.

  2. Photoaffinity antigens for human γδ T cells1

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    Sarikonda, Ghanashyam; Wang, Hong; Puan, Kia-Joo; Liu, Xiao-hui; Lee, Hoi K.; Song, Yongcheng; Distefano, Mark D.; Oldfield, Eric; Prestwich, Glenn D.; Morita, Craig T.

    2009-01-01

    Vγ2Vδ2 T cells comprise the major subset of peripheral blood γ δ T cells in humans and expand during infections by recognizing small, nonpeptide prenyl pyrophosphates. These molecules include (E)-4-hydroxy-3-methyl-but-2-enyl-pyrophosphate (HMBPP), a microbial isoprenoid intermediate, and isopentenyl pyrophosphate (IPP), an endogenous isoprenoid intermediate. Recognition of these nonpeptide antigens is mediated by the Vγ2Vδ2 T cell antigen receptor (TCR). Several findings suggest that prenyl pyrophosphates are presented by an antigen presenting molecule: contact between T cells and APCs is required; the antigens do not bind the Vγ2Vδ2 TCR directly; and antigen recognition is abrogated by TCR mutations in CDRs distant from the putative antigen recognition site. Identification of the putative antigen presenting molecule, however, has been hindered by the inability to achieve stable association of nonpeptide prenyl pyrophosphate antigens with the presenting molecule. In this study, we show that photoaffinity analogs of HMBPP, meta/para-benzophenone-(methylene)-prenyl pyrophosphates (m/p-BZ-(C)-C5-OPP), can cross-link to the surface of tumor cell lines and be presented as antigens to γ δ T cells. Mutant tumor cell lines lacking MHC class I, MHC class II, β2-microglobulin, and CD1, as well as tumor cell lines from a variety of tissues and individuals, will all crosslink to and present m-BZ-C5-OPP. Finally, pulsing of BZ-(C)-C5-OPP is inhibited by IPP and an inactive analog, suggesting that they bind to the same molecule. Taken together, these results suggest that nonpeptide antigens are presented by a novel antigen presenting molecule that is widely distributed, non-polymorphic, but not classical MHC class I, MHC class II, or CD1. This is an author-produced version of a manuscript accepted for publication in The Journal of Immunology (The JI). The American Association of Immunologists, Inc. (AAI), publisher of The JI, holds the copyright to this manuscript

  3. Prenylated flavones from Artocarpus altilis.

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    Shamaun, Shireen Shaharina; Rahmani, Mawardi; Hashim, Najihah Mohd; Ismail, Hazar Bebe Mohd; Sukari, Mohd Aspollah; Lian, Gwendoline Ee Cheng; Go, Rusea

    2010-10-01

    Six prenylated flavones, including one new compound, were isolated and identified from the stem bark extracts of Artocarpus altilis. The new prenylated flavone hydroxyartocarpin (1) was characterized as 3-(gamma,gamma-dimethylallyl)-6-isopentenyl-5,8,2',4'-tetrahydroxy-7-methoxyflavone and the known compounds were artocarpin (2), morusin (3), cycloartobiloxanthone (4), cycloartocarpin A (5) and artoindonesianin V (6). The structures of the compounds were determined by spectroscopic methods (IR, MS, (1)H-NMR and (13)C-NMR) and comparison with published data for the known compounds.

  4. Multifunctional Prenylated Peptides for Live Cell Analysis

    Science.gov (United States)

    Wollack, James W.; Zeliadt, Nicholette A.; Mullen, Daniel G.; Amundson, Gregg; Geier, Suzanne; Falkum, Stacy; Wattenberg, Elizabeth V.; Barany, George; Distefano, Mark D.

    2009-01-01

    Protein prenylation is a common post-translational modification present in eukaryotic cells. Many key proteins involved in signal transduction pathways are prenylated and inhibition of prenylation can be useful as a therapeutic intervention. While significant progress has been made in understanding protein prenylation in vitro, we have been interested in studying this process in living cells, including the question of where prenylated molecules localize. Here, we describe the synthesis and live cell analysis of a series of fluorescently labeled multifunctional peptides, based on the C-terminus of the naturally prenylated protein CDC42. A synthetic route was developed that features a key Acm to Scm protecting group conversion. This strategy was compatible with acid-sensitive isoprenoid moieties, and allowed incorporation of an appropriate fluorophore as well as a cell-penetrating sequence (penetratin). These peptides are able to enter cells through different mechanisms, depending on the presence or absence of the penetratin vehicle and the nature of the prenyl group attached. Interestingly, prenylated peptides lacking penetratin are able to enter cells freely through an energy-independent process, and localize in a perinuclear fashion. This effect extends to a prenylated peptide that includes a full “CAAX box” sequence (specifically, CVLL). Hence, these peptides open the door for studies of protein prenylation in living cells, including enzymatic processing and intracellular peptide trafficking. Moreover, the synthetic strategy developed here should be useful for the assembly of other types of peptides that contain acid sensitive functionalities. PMID:19425596

  5. 3-Hydroxymethyl coenzyme A reductase inhibition attenuates spontaneous smooth muscle tone via RhoA/ROCK pathway regulated by RhoA prenylation.

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    Rattan, Satish

    2010-06-01

    RhoA prenylation may play an important step in the translocation of RhoA in the basal internal anal sphincter (IAS) smooth muscle tone. Statins inhibit downstream posttranslational RhoA prenylation by 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibition (HMGCRI). The role of statins in relation to RhoA prenylation in the pathophysiology of the spontaneously tonic smooth muscle has not been investigated. In the present studies, we determined the effect of classical HMGCRI simvastatin on the basal IAS tone and RhoA prenylation and in the levels of RhoA/Rho kinase (ROCK) in the cytosolic vs. membrane fractions of the smooth muscle. Simvastatin produced concentration-dependent decrease in the IAS tone (via direct actions at the smooth muscle cells). The decrease in the IAS tone by simvastatin was associated with the decrease in the prenylation of RhoA, as well as RhoA/ROCK in the membrane fractions of the IAS, in the basal state. The inhibitory effects of the HMGCRI were completely reversible by geranylgeranyltransferase substrate geranylgeranyl pyrophosphate. Relaxation of the IAS smooth muscle via HMGCRI simvastatin is mediated via the downstream decrease in the levels of RhoA prenylation and ROCK activity. Studies support the concept that RhoA prenylation leading to RhoA/ROCK translocation followed by activation is important for the basal tone in the IAS. Data suggest that the role of HMG-CoA reductase may go beyond cholesterol biosynthesis, such as the regulation of the smooth muscle tone. The studies have important implications in the pathophysiological mechanisms and in the novel therapeutic approaches for anorectal motility disorders.

  6. Functional characterization of the Xanthophyllomyces dendrorhous farnesyl pyrophosphate synthase and geranylgeranyl pyrophosphate synthase encoding genes that are involved in the synthesis of isoprenoid precursors.

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    Jennifer Alcaíno

    Full Text Available The yeast Xanthophyllomyces dendrorhous synthesizes the carotenoid astaxanthin, which has applications in biotechnology because of its antioxidant and pigmentation properties. However, wild-type strains produce too low amounts of carotenoids to be industrially competitive. Considering this background, it is indispensable to understand how the synthesis of astaxanthin is controlled and regulated in this yeast. In this work, the steps leading to the synthesis of the carotenoid precursor geranylgeranyl pyrophosphate (GGPP, C20 in X. dendrorhous from isopentenyl pyrophosphate (IPP, C5 and dimethylallyl pyrophosphate (DMAPP, C5 was characterized. Two prenyl transferase encoding genes, FPS and crtE, were expressed in E. coli. The enzymatic assays using recombinant E. coli protein extracts demonstrated that FPS and crtE encode a farnesyl pyrophosphate (FPP, C15 synthase and a GGPP-synthase, respectively. X. dendrorhous FPP-synthase produces geranyl pyrophosphate (GPP, C10 from IPP and DMAPP and FPP from IPP and GPP, while the X. dendrorhous GGPP-synthase utilizes only FPP and IPP as substrates to produce GGPP. Additionally, the FPS and crtE genes were over-expressed in X. dendrorhous, resulting in an increase of the total carotenoid production. Because the parental strain is diploid, the deletion of one of the alleles of these genes did not affect the total carotenoid production, but the composition was significantly altered. These results suggest that the over-expression of these genes might provoke a higher carbon flux towards carotenogenesis, most likely involving an earlier formation of a carotenogenic enzyme complex. Conversely, the lower carbon flux towards carotenogenesis in the deletion mutants might delay or lead to a partial formation of a carotenogenic enzyme complex, which could explain the accumulation of astaxanthin carotenoid precursors in these mutants. In conclusion, the FPS and the crtE genes represent good candidates to manipulate to

  7. Functional characterization of the Xanthophyllomyces dendrorhous farnesyl pyrophosphate synthase and geranylgeranyl pyrophosphate synthase encoding genes that are involved in the synthesis of isoprenoid precursors.

    Science.gov (United States)

    Alcaíno, Jennifer; Romero, Ignacio; Niklitschek, Mauricio; Sepúlveda, Dionisia; Rojas, María Cecilia; Baeza, Marcelo; Cifuentes, Víctor

    2014-01-01

    The yeast Xanthophyllomyces dendrorhous synthesizes the carotenoid astaxanthin, which has applications in biotechnology because of its antioxidant and pigmentation properties. However, wild-type strains produce too low amounts of carotenoids to be industrially competitive. Considering this background, it is indispensable to understand how the synthesis of astaxanthin is controlled and regulated in this yeast. In this work, the steps leading to the synthesis of the carotenoid precursor geranylgeranyl pyrophosphate (GGPP, C20) in X. dendrorhous from isopentenyl pyrophosphate (IPP, C5) and dimethylallyl pyrophosphate (DMAPP, C5) was characterized. Two prenyl transferase encoding genes, FPS and crtE, were expressed in E. coli. The enzymatic assays using recombinant E. coli protein extracts demonstrated that FPS and crtE encode a farnesyl pyrophosphate (FPP, C15) synthase and a GGPP-synthase, respectively. X. dendrorhous FPP-synthase produces geranyl pyrophosphate (GPP, C10) from IPP and DMAPP and FPP from IPP and GPP, while the X. dendrorhous GGPP-synthase utilizes only FPP and IPP as substrates to produce GGPP. Additionally, the FPS and crtE genes were over-expressed in X. dendrorhous, resulting in an increase of the total carotenoid production. Because the parental strain is diploid, the deletion of one of the alleles of these genes did not affect the total carotenoid production, but the composition was significantly altered. These results suggest that the over-expression of these genes might provoke a higher carbon flux towards carotenogenesis, most likely involving an earlier formation of a carotenogenic enzyme complex. Conversely, the lower carbon flux towards carotenogenesis in the deletion mutants might delay or lead to a partial formation of a carotenogenic enzyme complex, which could explain the accumulation of astaxanthin carotenoid precursors in these mutants. In conclusion, the FPS and the crtE genes represent good candidates to manipulate to favor

  8. Estrogenicity and metabolism of prenylated flavonoids and isoflavonoids

    NARCIS (Netherlands)

    Schans, van de M.G.M.

    2015-01-01

      Binding of (prenylated) flavonoids and isoflavonoids to the human estrogen receptors (hERs) might result in beneficial health effects in vivo. To understand structure-activity relationships of prenylated (iso)flavonoids towards the hERs, prenylated (iso)flavonoids were purified from extracts

  9. A new prenylated aurone from Artocarpus altilis.

    Science.gov (United States)

    Huong, Tran Thu; Cuong, Nguyen Xuan; Tram, Le Huyen; Quang, Tran Thuong; Duong, Le Van; Nam, Nguyen Hoai; Dat, Nguyen Tien; Huong, Phan Thi Thanh; Diep, Chau Ngoc; Kiem, Phan Van; Minh, Chau Van

    2012-01-01

    Phytochemical study of the methanol extract of Artocarpus altilis resulted in the isolation of a new prenylated aurone, artocarpaurone (1), together with eight known compounds including two prenylated chalcones (2 and 3), three prenylated flavanones (4-6), and three triterpenes (7-9). The structure of 1 was elucidated as 6-hydroxy-2-[8-hydroxy-2-methyl-2-(4-methyl-3-pentenyl)-2H-1-benzopyran-5-ylmethylene]-3(2H)-benzofuranone by spectroscopic methods including 1D and 2D NMR spectra and FT-ICR-MS. Compound 1 showed moderate nitric oxide radical scavenging activity, whereas 2 and 3 had moderate 2,2-diphenyl-1-picrylhydrazyl radical scavenging effect, compared with the positive control (+)-catechin.

  10. Rare prenylated flavonoids from Tephrosia purpurea.

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    Hegazy, Mohamed-Elamir F; Abd el-Razek, Mohamed H; Nagashima, Fumihiro; Asakawa, Yoshinori; Paré, Paul W

    2009-01-01

    Chemical investigations of aerial parts of Tephrosia purpurea yielded the rare prenylated flavonoids, tephropurpulin A (1) and isoglabratephrin (2), in addition to a previously identified flavonoid, glabratephrin (3). Structures were established by 1D and 2D NMR spectroscopy, as well as by HR-MS analysis; for compounds 2 and 3, structures were confirmed by X-ray analysis.

  11. Mechanistic insights into Mg2+-independent prenylation by CloQ from classical molecular mechanics and hybrid quantum mechanics/molecular mechanics molecular dynamics simulations.

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    Bayse, Craig A; Merz, Kenneth M

    2014-08-05

    Understanding the mechanism of prenyltransferases is important to the design of engineered proteins capable of synthesizing derivatives of naturally occurring therapeutic agents. CloQ is a Mg(2+)-independent aromatic prenyltransferase (APTase) that transfers a dimethylallyl group to 4-hydroxyphenylpyruvate in the biosynthetic pathway for clorobiocin. APTases consist of a common ABBA fold that defines a β-barrel containing the reaction cavity. Positively charged basic residues line the inside of the β-barrel of CloQ to activate the pyrophosphate leaving group to replace the function of the Mg(2+) cofactor in other APTases. Classical molecular dynamics simulations of CloQ, its E281G and F68S mutants, and the related NovQ were used to explore the binding of the 4-hydroxyphenylpyruvate (4HPP) and dimethylallyl diphosphate substrates in the reactive cavity and the role of various conserved residues. Hybrid quantum mechanics/molecular mechanics potential of mean force (PMF) calculations show that the effect of the replacement of the Mg(2+) cofactor with basic residues yields a similar activation barrier for prenylation to Mg(2+)-dependent APTases like NphB. The topology of the binding pocket for 4HPP is important for selective prenylation at the ortho position of the ring. Methylation at this position alters the conformation of the substrate for O-prenylation at the phenol group. Further, a two-dimensional PMF scan shows that a "reverse" prenylation product may be a possible target for protein engineering.

  12. Prenylated Rab acceptor protein is a receptor for prenylated small GTPases.

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    Figueroa, C; Taylor, J; Vojtek, A B

    2001-07-27

    Localization of Ras and Ras-like proteins to the correct subcellular compartment is essential for these proteins to mediate their biological effects. Many members of the Ras superfamily (Ha-Ras, N-Ras, TC21, and RhoA) are prenylated in the cytoplasm and then transit through the endomembrane system on their way to the plasma membrane. The proteins that aid in the trafficking of the small GTPases have not been well characterized. We report here that prenylated Rab acceptor protein (PRA1), which others previously identified as a prenylation-dependent receptor for Rab proteins, also interacts with Ha-Ras, RhoA, TC21, and Rap1a. The interaction of these small GTPases with PRA1 requires their post-translational modification by prenylation. The prenylation-dependent association of PRA1 with multiple GTPases is conserved in evolution; the yeast PRA1 protein associates with both Ha-Ras and RhoA. Earlier studies reported the presence of PRA1 in the Golgi, and we show here that PRA1 co-localizes with Ha-Ras and RhoA in the Golgi compartment. We suggest that PRA1 acts as an escort protein for small GTPases by binding to the hydrophobic isoprenoid moieties of the small GTPases and facilitates their trafficking through the endomembrane system.

  13. Prenylated flavonoids from maclura tinctoria fruits

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    Oyama, Sayuri de Oliveira; Souza, Luiz Antonio de [Departamento de Biologia, Universidade Estadual de Maringa, PR (Brazil); Baldoqui, Debora Cristina; Sarragiotto, Maria Helena [Departamento de Quimica, Universidade Estadual de Maringa, PR (Brazil); Silva, Adriano Antonio, E-mail: aasilva@ufac.br [Departamento de Ciencias da Natureza, Universidade Federal do Acre, AC (Brazil)

    2013-09-01

    A phytochemical investigation of Maclura tinctoria fruits yielded five flavonoids, including one prenylated flavonol (licoflavonol) and four prenylated isoflavones (wighteone, derrone, alpinum isoflavone, and 6-(2,2-dimethyl-2H-chromen-6-yl)-2-(1-hydroxy-1-methylethyl) -2,3-dihydro-5H-furo[3,2-g]chromen-5-one). The structures of the isolates were established by analyzing their spectroscopic data. Compound 6-(2,2-dimethyl-2H-chromen-6-yl) -2-(1-hydroxy-1-methylethyl)-2,3-ihydro-5H-furo[3,2-g]chromen-5-one is new and the other isolates are described for the first time in this species. (author)

  14. Five new prenylated chalcones from Desmodium renifolium.

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    Li, Yan-Ping; Yang, Yu-Chun; Li, Yin-Ke; Jiang, Zhi-Yong; Huang, Xiang-Zhong; Wang, Wei-Guang; Gao, Xue-Mei; Hu, Qiu-Fen

    2014-06-01

    Five unusual new prenylated chalcones, renifolins D-H (1-5), were isolated from whole Desmodium renifolium plants. All of their structures were determined by spectroscopic methods including 1D and 2D NMR. All of the isolates were evaluated for cytotoxicity using five tumor cell lines. Compounds 2 and 3 exhibited cytotoxicity against A549 cells, with IC50 values of 2.8 and 2.2 μM, respectively.

  15. Anti-inflammatory Natural Prenylated Phenolic Compounds - Potential Lead Substances.

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    Brezáni, Viliam; Šmejkal, Karel; Hošek, Jan; Tomášová, Veronika

    2017-08-10

    Natural phenolics are secondary plant metabolites, which can be divided into several categories with the common structural feature of phenolic hydroxyl. The biological activity of phenolics is often modified and enhanced by prenylation by prenyl and geranyl; higher terpenoid chains are rare. The type of prenyl connection and modification affects their biological activity. This review summarizes information about prenylated phenols and some of their potential sources, and provides an overview of their anti-inflammatory potential in vitro and in vivo. The literature search was performed using Scifinder and keywords prenyl, phenol, and inflammation. For individual compounds, an additional search was performed to find information about further activities and mechanisms of effects. We summarized the effects of prenylated phenolics in vitro in cellular or biochemical systems on the production and release of inflammation-related cytokines; their effects on inhibition of cyclooxygenases and lipoxygenases; the effects on production of nitric oxide, antiradical and antioxidant activity; and the effect on the inhibition of the release of enzymes and mediators from neutrophils, mast cells and macrophages. The information about the antiphlogistic potential of prenylated phenolics is further supported by a review of their action in animal models. Almost 400 prenylated phenols were reviewed to overview their anti-inflammatory effect. The bioactivity of several prenylated phenols was confirmed also using in vivo assays. A pool of natural prenylated phenols represents a source of inspiration for synthesis, and prenylated phenols as components of various medicinal plants used to combat inflammation could be their active principles. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  16. Colloidal iron(III) pyrophosphate particles

    NARCIS (Netherlands)

    Rossi, L.; Velikov, K. P.; Philipse, A.P.

    2014-01-01

    Ferric pyrophosphate is a widely used material in the area of mineral fortification but its synthesis and properties in colloidal form are largely unknown. In this article, we report on the synthesis and characterisation of colloidal iron(III) pyrophosphate particles with potential for application a

  17. 21 CFR 184.1304 - Ferric pyrophosphate.

    Science.gov (United States)

    2010-04-01

    ... colorless powder. It is prepared by reacting sodium pyrophosphate with ferric citrate. (b) The ingredient... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Ferric pyrophosphate. 184.1304 Section 184.1304 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED)...

  18. Prenyl sulfates as alkylating reagents for mercapto amino acids.

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    Maltsev, Sergey; Sizova, Olga; Utkina, Natalia; Shibaev, Vladimir; Chojnacki, Tadeusz; Jankowski, Wieslaw; Swiezewska, Ewa

    2008-01-01

    A new methodology for prenylation of thiol compounds has been developed. The approach is based on the use of prenyl sulfates as new reagents for S-prenylation of benzenethiol and cysteamine in aqueous systems. The C(10)-prenols geraniol and nerol that differ in the configuration (E or Z, correspondingly) of the alpha-isoprene unit were efficiently O-sulfated in the presence of a pyridine-SO(3') complex. The obtained geranyl and neryl sulfates were tested as alkylating agents. These compounds were chosen to reveal the influence of the alpha-isoprene unit configuration on their alkylation (prenylation) ability. S-Geranyl cysteine was prepared to demonstrate the applicability of this method for prenylation of peptides containing mercapto amino acids.

  19. Inositol pyrophosphates: between signalling and metabolism.

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    Wilson, Miranda S C; Livermore, Thomas M; Saiardi, Adolfo

    2013-06-15

    The present review will explore the insights gained into inositol pyrophosphates in the 20 years since their discovery in 1993. These molecules are defined by the presence of the characteristic 'high energy' pyrophosphate moiety and can be found ubiquitously in eukaryotic cells. The enzymes that synthesize them are similarly well distributed and can be found encoded in any eukaryote genome. Rapid progress has been made in characterizing inositol pyrophosphate metabolism and they have been linked to a surprisingly diverse range of cellular functions. Two decades of work is now beginning to present a view of inositol pyrophosphates as fundamental, conserved and highly important agents in the regulation of cellular homoeostasis. In particular it is emerging that energy metabolism, and thus ATP production, is closely regulated by these molecules. Much of the early work on these molecules was performed in the yeast Saccharomyces cerevisiae and the social amoeba Dictyostelium discoideum, but the development of mouse knockouts for IP6K1 and IP6K2 [IP6K is IP6 (inositol hexakisphosphate) kinase] in the last 5 years has provided very welcome tools to better understand the physiological roles of inositol pyrophosphates. Another recent innovation has been the use of gel electrophoresis to detect and purify inositol pyrophosphates. Despite the advances that have been made, many aspects of inositol pyrophosphate biology remain far from clear. By evaluating the literature, the present review hopes to promote further research in this absorbing area of biology.

  20. Clomazone Does Not Inhibit the Conversion of Isopentenyl Pyrophosphate to Geranyl, Farnesyl, or Geranylgeranyl Pyrophosphate in Vitro 1

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    Croteau, Rodney

    1992-01-01

    Clomazone, an herbicide that reduces the levels of leaf carotenoids and chlorophylls, is thought to act by inhibiting isopentenyl pyrophosphate isomerase or the prenyltransferases responsible for the synthesis of geranylgeranyl pyrophosphate. Cell-free extracts prepared from the oil glands of common sage (Salvia officinalis) are capable of converting isopentenyl pyrophosphate to geranylgeranyl pyrophosphate. Clomazone at 250 micromolar (a level that produced leaf bleaching) had no detectable effect on the activity of the relevant enzymes (isopentenyl pyrophosphate isomerase and the three prenyltransferases, geranyl, farnesyl, and geranylgeranyl pyrophosphate synthases). Thus, inhibition of geranylgeranyl pyrophosphate biosynthesis does not appear to be the mode of action of this herbicide. PMID:16668824

  1. Clomazone does not inhibit the conversion of isopentenyl pyrophosphate to geranyl, farnesyl, or geranylgeranyl pyrophosphate in vitro.

    Science.gov (United States)

    Croteau, R

    1992-04-01

    Clomazone, an herbicide that reduces the levels of leaf carotenoids and chlorophylls, is thought to act by inhibiting isopentenyl pyrophosphate isomerase or the prenyltransferases responsible for the synthesis of geranylgeranyl pyrophosphate. Cell-free extracts prepared from the oil glands of common sage (Salvia officinalis) are capable of converting isopentenyl pyrophosphate to geranylgeranyl pyrophosphate. Clomazone at 250 micromolar (a level that produced leaf bleaching) had no detectable effect on the activity of the relevant enzymes (isopentenyl pyrophosphate isomerase and the three prenyltransferases, geranyl, farnesyl, and geranylgeranyl pyrophosphate synthases). Thus, inhibition of geranylgeranyl pyrophosphate biosynthesis does not appear to be the mode of action of this herbicide.

  2. Purification of prenylated proteins by affinity chromatography on cyclodextrin-modified agarose

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    Chung, Jinhwa A.; Wollack, James W.; Hovlid, Marisa L.; Okesli, Ayse; Chen, Yan; Mueller, Joachim D.; Distefano, Mark D.; Taton, T. Andrew

    2009-01-01

    Although protein prenylation is widely studied, there are few good methods for isolating prenylated proteins from their non-prenylated relatives. We report that crosslinked agarose (e.g., Sepharose) chromatography media that has been chemically functionalized with β-cyclodextrin (β-CD) is extremely effective in affinity chromatography of prenylated proteins. In this study, a variety of proteins with C-terminal prenylation target (“CAAX box”) sequences were enzymatically prenylated in vitro with natural and non-natural prenyl diphosphate substrates. The prenylated protein products could then be isolated from starting materials by gravity chromatography or fast protein liquid chromatography (FPLC) on a β-CD-Sepharose column. One particular prenylation reaction—farnesylation of a mCherry-CAAX fusion construct—was studied in detail. In this case, purified farnesylated product was unambiguously identified by electrospray mass spectrometry. In addition, when mCherry-CAAX was prenylated with a non-natural, functional isoprenoid substrate, the functional group was maintained by chromatography on β-CD-Sepharose, such that the resulting protein could be selectively bound at its C terminus to complementary functionality on a solid substrate. Finally, β-CD-Sepharose FPLC was used to isolate prenylated mCherry-CAAX from crude HeLa cell lysate, as a model for purifying prenylated proteins from cell extracts. We propose that this method could be generally useful to the community of researchers studying protein prenylation. PMID:18834849

  3. Ceramics based on calcium pyrophosphate nanopowders

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    Tatiana V. Safronova

    2013-03-01

    Full Text Available Present work is aimed at the fabrication of resorbable bioceramics based on calcium pyrophosphate (CPP from the synthesized powders of amorphous hydrated calcium pyrophosphate (AHCPP. Amorphous hydratedcalcium pyrophosphate in the form of nanopowders was precipitated from Ca(NO3 2 and (NH4 4P2O7 solutions at room temperature in the presence of PO3– ions. Crystalline CPP powder was fabricated from AHCPP by its thermal decomposition at 600 °C and consisted of β- and α- phase. Small particles, with the size less than 200 nm, were formed promoting sintering of the ceramic material. The final sample, sintered at 900 °C, exhibits microstructure with submicron grains, apparent density of 87% of theoretical density (TD and demonstrates tensile strength of 70 MPa.

  4. Cloning and enzymology analysis of farnesyl pyrophosphate synthase gene from a superior strain of Artemisia annua L

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    A cDNA(af1) encoding farnesyl pyrophosphate synthase AaFPS1 (FPS, EC2.5.1.1/EC2.5.1.10) from a high yield Artemisia annua strain 025 has been cloned from its cDNA library. Sequence analysis showed that the cDNA encoded a protein of 343 amino acid (aa) residues with molecular weight of 39 kD. Deduced aa sequence of the cDNA was similar to FPS from other plants, yeast and mammals, containing 5 conserved domains found in both prenyl transferase and polyprenyl synthase. The expression of the cDNA in Escherichia coli showed measurable specific activity of FPS in vitro. The enzyme was purified by ion exchange chromatography and its kinetics was measured. These results would further promote the molecular regulation of artemisinin biosynthesis.

  5. Prenyl transfer to aromatic substrates: genetics and enzymology.

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    Heide, Lutz

    2009-04-01

    Aromatic prenyltransferases catalyze the transfer of prenyl moieties to aromatic acceptor molecules and give rise to an astounding diversity of primary and secondary metabolites in plants, fungi and bacteria. Significant progress has been made in the biochemistry and genetics of this heterogeneous group of enzymes in the past years. After 30 years of extensive research on plant prenylflavonoid biosynthesis, finally the first aromatic prenyltransferases involved in the formation of these compounds have been cloned. In bacteria, investigations of the newly discovered family of ABBA prenyltransferases revealed a novel type of protein fold, the PT barrel. In fungi, a group of closely related indole prenyltransferase was found to carry out aromatic prenylations with different substrate specificity and regiospecificity, and to catalyze both regular and reverse prenylations.

  6. Rapid membrane permeabilization of Listeria monocytogenes and Escherichia coli induced by antibacterial prenylated phenolic compounds from legumes

    NARCIS (Netherlands)

    Araya-Cloutier, Carla; Vincken, Jean Paul; Ederen, van Roan; Besten, den Heidy M.W.; Gruppen, Harry

    2018-01-01

    Prenylated phenolics from the Fabaceae are promising lead compounds for new antibacterials. Pools enriched in prenylated phenolics were made from lupine, peanut and soybean seedlings. One pool was rich in chain prenylated isoflavones (cIsf), one in chain prenylated stilbenoids (cSti), one in chain

  7. Prenylated Dihydrochalcones from Artocarpus altilis as Antiausterity Agents.

    Science.gov (United States)

    Nguyen, Mai Thanh Thi; Nguyen, Nhan Trung; Awale, Suresh

    2015-01-01

    Human pancreatic cancer cell lines have remarkable tolerance to nutrition starvation, which enables them to survive under a tumor microenvironment. A novel antiausterity strategy in anticancer drug discovery led to the discovery of agents that preferentially inhibit the survival of cancer cells under low nutrient conditions. Artocarpus altilis (Family: Moraceae) is commonly referred to as breadfruit, traditionally for the treatment of many diseases. Many prenylated flavonoid and prenylated chalocones together with their cancer cell cytotoxicity were reported from this plant. This chapter briefly summarizes the constituents, biosynthesis, cytotoxicity, and antiausterity activity on PANC-1 human pancreatic cancer cell line of A. altilis. © 2015 Elsevier Inc. All rights reserved.

  8. Morphology of colloidal metal pyrophosphate salts

    NARCIS (Netherlands)

    van Leeuwen, Y.M.; Velikov, K.; Kegel, W.K.

    2012-01-01

    We report the preparation and characterization of colloidal particles of several pyrophosphate metal salts, including, for the first time, salts containing multiple metals. These materials are compared in order to determine the influence of the composition and experimental conditions on particle

  9. Induction of prenylated isoflavonoids and stilbenoids in legumes

    NARCIS (Netherlands)

    Aisyah, S.

    2015-01-01

    The germination of legume seeds in the presence or absence of stress factors was studied with respect to compositional changes in prenylated isoflavonoids and stilbenoids. Different strategies were applied using (i) different types of legume seed, (ii) different stress factors i.e. biotic, abiotic

  10. Induction of prenylated isoflavonoids and stilbenoids in legumes

    NARCIS (Netherlands)

    Aisyah, S.

    2015-01-01

    The germination of legume seeds in the presence or absence of stress factors was studied with respect to compositional changes in prenylated isoflavonoids and stilbenoids. Different strategies were applied using (i) different types of legume seed, (ii) different stress factors i.e. biotic, abiotic a

  11. Analysis of Dictyostelium discoideum Inositol Pyrophosphate Metabolism by Gel Electrophoresis

    Science.gov (United States)

    Pisani, Francesca; Livermore, Thomas; Rose, Giuseppina; Chubb, Jonathan Robert; Gaspari, Marco; Saiardi, Adolfo

    2014-01-01

    The social amoeba Dictyostelium discoideum was instrumental in the discovery and early characterization of inositol pyrophosphates, a class of molecules possessing highly-energetic pyrophosphate bonds. Inositol pyrophosphates regulate diverse biological processes and are attracting attention due to their ability to control energy metabolism and insulin signalling. However, inositol pyrophosphate research has been hampered by the lack of simple experimental procedures to study them. The recent development of polyacrylamide gel electrophoresis (PAGE) and simple staining to resolve and detect inositol pyrophosphate species has opened new investigative possibilities. This technology is now commonly applied to study in vitro enzymatic reactions. Here we employ PAGE technology to characterize the D. discoideum inositol pyrophosphate metabolism. Surprisingly, only three major bands are detectable after resolving acidic extract on PAGE. We have demonstrated that these three bands correspond to inositol hexakisphosphate (IP6 or Phytic acid) and its derivative inositol pyrophosphates, IP7 and IP8. Biochemical analyses and genetic evidence were used to establish the genuine inositol phosphate nature of these bands. We also identified IP9 in D. discoideum cells, a molecule so far detected only from in vitro biochemical reactions. Furthermore, we discovered that this amoeba possesses three different inositol pentakisphosphates (IP5) isomers, which are largely metabolised to inositol pyrophosphates. Comparison of PAGE with traditional Sax-HPLC revealed an underestimation of the cellular abundance of inositol pyrophosphates by traditional methods. In fact our study revealed much higher levels of inositol pyrophosphates in D. discoideum in the vegetative state than previously detected. A three-fold increase in IP8 was observed during development of D. discoideum a value lower that previously reported. Analysis of inositol pyrophosphate metabolism using ip6k null amoeba revealed

  12. Analysis of Dictyostelium discoideum inositol pyrophosphate metabolism by gel electrophoresis.

    Science.gov (United States)

    Pisani, Francesca; Livermore, Thomas; Rose, Giuseppina; Chubb, Jonathan Robert; Gaspari, Marco; Saiardi, Adolfo

    2014-01-01

    The social amoeba Dictyostelium discoideum was instrumental in the discovery and early characterization of inositol pyrophosphates, a class of molecules possessing highly-energetic pyrophosphate bonds. Inositol pyrophosphates regulate diverse biological processes and are attracting attention due to their ability to control energy metabolism and insulin signalling. However, inositol pyrophosphate research has been hampered by the lack of simple experimental procedures to study them. The recent development of polyacrylamide gel electrophoresis (PAGE) and simple staining to resolve and detect inositol pyrophosphate species has opened new investigative possibilities. This technology is now commonly applied to study in vitro enzymatic reactions. Here we employ PAGE technology to characterize the D. discoideum inositol pyrophosphate metabolism. Surprisingly, only three major bands are detectable after resolving acidic extract on PAGE. We have demonstrated that these three bands correspond to inositol hexakisphosphate (IP₆ or Phytic acid) and its derivative inositol pyrophosphates, IP₇ and IP₈. Biochemical analyses and genetic evidence were used to establish the genuine inositol phosphate nature of these bands. We also identified IP₉ in D. discoideum cells, a molecule so far detected only from in vitro biochemical reactions. Furthermore, we discovered that this amoeba possesses three different inositol pentakisphosphates (IP₅) isomers, which are largely metabolised to inositol pyrophosphates. Comparison of PAGE with traditional Sax-HPLC revealed an underestimation of the cellular abundance of inositol pyrophosphates by traditional methods. In fact our study revealed much higher levels of inositol pyrophosphates in D. discoideum in the vegetative state than previously detected. A three-fold increase in IP₈ was observed during development of D. discoideum a value lower that previously reported. Analysis of inositol pyrophosphate metabolism using ip6k null amoeba

  13. Analysis of Dictyostelium discoideum inositol pyrophosphate metabolism by gel electrophoresis.

    Directory of Open Access Journals (Sweden)

    Francesca Pisani

    Full Text Available The social amoeba Dictyostelium discoideum was instrumental in the discovery and early characterization of inositol pyrophosphates, a class of molecules possessing highly-energetic pyrophosphate bonds. Inositol pyrophosphates regulate diverse biological processes and are attracting attention due to their ability to control energy metabolism and insulin signalling. However, inositol pyrophosphate research has been hampered by the lack of simple experimental procedures to study them. The recent development of polyacrylamide gel electrophoresis (PAGE and simple staining to resolve and detect inositol pyrophosphate species has opened new investigative possibilities. This technology is now commonly applied to study in vitro enzymatic reactions. Here we employ PAGE technology to characterize the D. discoideum inositol pyrophosphate metabolism. Surprisingly, only three major bands are detectable after resolving acidic extract on PAGE. We have demonstrated that these three bands correspond to inositol hexakisphosphate (IP₆ or Phytic acid and its derivative inositol pyrophosphates, IP₇ and IP₈. Biochemical analyses and genetic evidence were used to establish the genuine inositol phosphate nature of these bands. We also identified IP₉ in D. discoideum cells, a molecule so far detected only from in vitro biochemical reactions. Furthermore, we discovered that this amoeba possesses three different inositol pentakisphosphates (IP₅ isomers, which are largely metabolised to inositol pyrophosphates. Comparison of PAGE with traditional Sax-HPLC revealed an underestimation of the cellular abundance of inositol pyrophosphates by traditional methods. In fact our study revealed much higher levels of inositol pyrophosphates in D. discoideum in the vegetative state than previously detected. A three-fold increase in IP₈ was observed during development of D. discoideum a value lower that previously reported. Analysis of inositol pyrophosphate metabolism using

  14. Effect of pyrophosphate on the light scatter in KDP crystal

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Pyrophosphate doped potassium dihydrogen phosphate (KDP) crystal was grown from aqueous solution by the temperature lowering method. Light scatter in KDP crystal was detected with the ultramicroscopic method. The light scatter in KDP crystal was aggravated when pyrophosphate was doped into the growth solution, which was distributed ununiformly in prism and pyramidal sectors of KDP crystal. Different effects of pyrophosphate on prism and pyramidal sectors of KDP crystal can explain this case. The transmission in this crystal was measured, showing that pyrophosphate affects the transmission evidently.

  15. A New Prenylated Xanthone from Root Barks of Cudrania cochinchinensis

    Institute of Scientific and Technical Information of China (English)

    LIU Zhi-ping; WEI Wan-xing; ZHOU Min; GAN Chun-fang; LIU Sheng

    2013-01-01

    Objective To study the chemical constituents from the root barks of Cudrania cochinchinensis.Methods The chemical constituents were isolated and purified by silica gel column chromatography.The structures of the compounds were identified on the basis of spectral data (MS,1H-NMR,13C-NMR,and 2D NMR) and by the comparison of spectroscopic data with the reported values in the literatures.Results A new xanthone,1,6,7-trihydroxy-4-(1,1-dimethylallyl)-3-methoxyxanthone (1) and a known prenylated xanthone 1,5,6-trihydroxy-4-(1,l-dimethylallyl)-3-methoxyxanthone (isocudraniaxanthone B,2) were isolated from the root barks of C.cochinchinensis.Conclusion Compound 1 is a new prenylated xanthone.Isomers 1 and 2 are obtained from this plantfor the first time.

  16. Synthesis and DPPH Radical Scavenging Activity of Prenylated Phenol Derivatives

    Directory of Open Access Journals (Sweden)

    Héctor Carrasco

    2012-01-01

    Full Text Available The synthesis of twenty six prenylated phenols derivatives is reported. These compounds were obtained under mild conditions via Electrophilic Aromatic Substitution (EAS coupling reactions between phenol derivatives containing electron-donor subtituents and 3-methyl-2-buten-1-ol using BF3×OEt2. Dialkylations were also produced with this method. The formation of a chroman ring by intramolecular cyclization between a sp2 carbon from the prenyl group with the hydroxyl substituent in the ortho position occurred with some phenols. All the synthesized compounds were evaluated as antioxidants according to a DPPH radical scavenging activity assay. IC50 values of five synthesized compounds indicated they were as good antioxidants as Trolox™.

  17. Unusual prenylated phenols with antioxidant activities from Ganoderma cochlear.

    Science.gov (United States)

    Peng, XingRong; Liu, JieQing; Wang, CuiFang; Han, ZhongHui; Shu, Yi; Li, XuYang; Zhou, Lin; Qiu, MingHua

    2015-03-15

    Seven new prenylated phenols, five novel phenols (1-5) with polycyclic skeleton and two new phenols (6 and 7) with a carbon chain, along with one known compound (8) were isolated from the fruiting bodies of Ganoderma cochlear. The structures of new compounds were elucidated by the spectroscopic technologies, X-ray crystallography analysis and chiral HPLC chromatography. All compounds showed antioxidant effect in radical scavenging assays and a plausible biosynthetic pathway for 1-8 was proposed.

  18. Prenylated xanthone glucosides from Ural's lichen Umbilicaria proboscidea.

    Science.gov (United States)

    Rezanka, Tomás; Jáchymová, Jitka; Dembitsky, Valery M

    2003-02-01

    Two new compounds isolated from an extract of a Central Asian lichen [Umbilicaria proboscidea (L.) Schrader=Syn.: Gyrophora proboscidea (L.) Ach.] are glucosides with mono- and di-prenylated xanthones as the aglycones and a saccharide moiety from two glucoses linked at C-7. The structures were elucidated on the basis of extensive spectroscopic analysis (1D and 2D NMR, MS, IR and UV) and by hydrolysis.

  19. Caged Protein Prenyltransferase Substrates: Tools for Understanding Protein Prenylation

    Energy Technology Data Exchange (ETDEWEB)

    DeGraw, Amanda J.; Hast, Michael A.; Xu, Juhua; Mullen, Daniel; Beese, Lorena S.; Barany, George; Distefano, Mark D. (Duke); (UMM)

    2010-11-15

    Originally designed to block the prenylation of oncogenic Ras, inhibitors of protein farnesyltransferase currently in preclinical and clinical trials are showing efficacy in cancers with normal Ras. Blocking protein prenylation has also shown promise in the treatment of malaria, Chagas disease and progeria syndrome. A better understanding of the mechanism, targets and in vivo consequences of protein prenylation are needed to elucidate the mode of action of current PFTase (Protein Farnesyltransferase) inhibitors and to create more potent and selective compounds. Caged enzyme substrates are useful tools for understanding enzyme mechanism and biological function. Reported here is the synthesis and characterization of caged substrates of PFTase. The caged isoprenoid diphosphates are poor substrates prior to photolysis. The caged CAAX peptide is a true catalytically caged substrate of PFTase in that it is to not a substrate, yet is able to bind to the enzyme as established by inhibition studies and X-ray crystallography. Irradiation of the caged molecules with 350 nm light readily releases their cognate substrate and their photolysis products are benign. These properties highlight the utility of those analogs towards a variety of in vitro and in vivo applications.

  20. Inositol pyrophosphates inhibit synaptotagmin-dependent exocytosis.

    Science.gov (United States)

    Lee, Tae-Sun; Lee, Joo-Young; Kyung, Jae Won; Yang, Yoosoo; Park, Seung Ju; Lee, Seulgi; Pavlovic, Igor; Kong, Byoungjae; Jho, Yong Seok; Jessen, Henning J; Kweon, Dae-Hyuk; Shin, Yeon-Kyun; Kim, Sung Hyun; Yoon, Tae-Young; Kim, Seyun

    2016-07-19

    Inositol pyrophosphates such as 5-diphosphoinositol pentakisphosphate (5-IP7) are highly energetic inositol metabolites containing phosphoanhydride bonds. Although inositol pyrophosphates are known to regulate various biological events, including growth, survival, and metabolism, the molecular sites of 5-IP7 action in vesicle trafficking have remained largely elusive. We report here that elevated 5-IP7 levels, caused by overexpression of inositol hexakisphosphate (IP6) kinase 1 (IP6K1), suppressed depolarization-induced neurotransmitter release from PC12 cells. Conversely, IP6K1 depletion decreased intracellular 5-IP7 concentrations, leading to increased neurotransmitter release. Consistently, knockdown of IP6K1 in cultured hippocampal neurons augmented action potential-driven synaptic vesicle exocytosis at synapses. Using a FRET-based in vitro vesicle fusion assay, we found that 5-IP7, but not 1-IP7, exhibited significantly higher inhibitory activity toward synaptic vesicle exocytosis than IP6 Synaptotagmin 1 (Syt1), a Ca(2+) sensor essential for synaptic membrane fusion, was identified as a molecular target of 5-IP7 Notably, 5-IP7 showed a 45-fold higher binding affinity for Syt1 compared with IP6 In addition, 5-IP7-dependent inhibition of synaptic vesicle fusion was abolished by increasing Ca(2+) levels. Thus, 5-IP7 appears to act through Syt1 binding to interfere with the fusogenic activity of Ca(2+) These findings reveal a role of 5-IP7 as a potent inhibitor of Syt1 in controlling the synaptic exocytotic pathway and expand our understanding of the signaling mechanisms of inositol pyrophosphates.

  1. Two inositol hexakisphosphate kinases drive inositol pyrophosphate synthesis in plants

    Science.gov (United States)

    Inositol pyrophosphates are novel cellular signaling molecules with newly discovered roles in energy sensing and metabolic control. Studies in eukaryotes have revealed that these compounds turn over rapidly, and thus only small amounts accumulate. Inositol pyrophosphates have not been the subject of...

  2. Identification of prenylated pterocarpans and other isoflavonoids in Rhizopus spp. elicited soya bean seedlings by electrospray ionisation mass spectrometry.

    Science.gov (United States)

    Simons, Rudy; Vincken, Jean-Paul; Bohin, Maxime C; Kuijpers, Tomas F M; Verbruggen, Marian A; Gruppen, Harry

    2011-01-15

    Phytoalexins from soya are mainly characterised as prenylated pterocarpans, the glyceollins. Extracts of non-soaked and soaked soya beans, as well as that of soya seedlings, grown in the presence of Rhizopus microsporus var. oryzae, were screened for the presence of prenylated flavonoids with a liquid chromatography/mass spectrometry (LC/MS)-based screening method. The glyceollins I-III and glyceollidins I-II, belonging to the isoflavonoid subclass of the pterocarpans, were tentatively assigned. The formation of these prenylated pterocarpans was accompanied by that of other prenylated isoflavonoids of the subclasses of the isoflavones and the coumestans. It was estimated that approx. 40% of the total isoflavonoid content in Rhizopus-challenged soya bean seedlings were prenylated pterocarpans, whereas 7% comprised prenylated isoflavones and prenylated coumestans. The site of prenylation (A-ring or B-ring) of the prenylated isoflavones was tentatively annotated using positive-ion mode MS by comparing the (1,3) A(+) retro-Diels-Alder (RDA) fragments of prenylated and non-prenylated isoflavones. Furthermore, the fragmentation pathways of the five pterocarpans in negative-ion (NI) mode were proposed, which involved the cleavage of the C-ring and/or D-ring. The absence of the ring-closed prenyl (pyran or furan) gave exclusively -H(2) O(x,y) RDA fragments, whereas its presence gave predominantly the common RDA fragments. Copyright © 2010 John Wiley & Sons, Ltd.

  3. Prenylated flavonoids from Desmodium caudatum and evaluation of their anti-MRSA activity.

    Science.gov (United States)

    Sasaki, Hisako; Kashiwada, Yoshiki; Shibata, Hirofumi; Takaishi, Yoshihisa

    2012-10-01

    Seven prenylated flavonoids and a prenylated chromanochroman derivative, together with eight known flavonoids, were isolated from roots of Desmodium caudatum. The 15 structures were elucidated by extensive spectroscopic analyses. The antibacterial activity of many of other compounds was evaluated against methicillin-resistant Staphylococcus aureus (MRSA: COL and 5) by a disc diffusion method, and the minimum inhibitory concentrations (MICs) to MRSA were determined.

  4. Amyrisins A - C, O-Prenylated Flavonoids from Amyris madrensis⊥

    Science.gov (United States)

    Peng, Jiangnan; Hartley, Rachel M.; Fest, Gary A.; Mooberry, Susan L.

    2012-01-01

    Three new O-prenylated flavonoids, amyrisins A – C (1 –2), were isolated from the leaves and twigs of Amyris madrensis, along with the known compound, polygamain (4). The structures of 1 – 3 were elucidated based on the analysis of spectroscopic data. Amyrisins B (2) and C (3) showed moderate cytotoxicity against PC-3 and DU 145 prostate cancer cells with IC50 values of 17.5 and 23 μM, respectively while amyrisin A (1) did not show any cytotoxicity at the highest concentration tested, 50 μM. Polygamain (4) exhibited potent antiproliferative and microtubule depolymerizing activities. PMID:22260294

  5. Taichunamides: Prenylated Indole Alkaloids from Aspergillus taichungensis (IBT 19404)

    DEFF Research Database (Denmark)

    Kagiyama, Ippei; Kato, Hikaru; Nehira, Tatsuo

    2016-01-01

    Seven new prenylated indole alkaloids, taichunamides A–G, were isolated from the fungus Aspergillus taichungensis (IBT 19404). Taichunamides A and B contained an azetidine and 4‐pyridone units, respectively, and are likely biosynthesized from notoamide S via (+)‐6‐epi‐stephacidin A. Taichunamides C...... and D contain endoperoxide and methylsulfonyl units, respectively. This fungus produced indole alkaloids containing an anti‐bicyclo[2.2.2]diazaoctane core, whereas A. protuberus and A. amoenus produced congeners with a syn‐bicyclo[2.2.2]diazaoctane core. Plausible biosynthetic pathways to access...

  6. A New Prenylated Indole Diketopiperazine Alkaloid from Eurotium cristatum

    Directory of Open Access Journals (Sweden)

    Xianwei Zou

    2014-11-01

    Full Text Available A new prenylated indole diketopiperazine alkaloid, cristatumin F (1, and four known metabolites, echinulin (2, dehydroechinulin (3, neoechinulin A (4 and variecolorin O (5, were isolated from the crude extract of the fungus Eurotium cristatum. The structure of 1 was elucidated primarily by NMR and MS methods. The absolute configuration of 1 was assigned using Marfey’s method applied to its acid hydrolyzate. Cristatumin F (1 showed modest radical scavenging activity against DPPH radicals, and exhibited marginal attenuation of 3T3L1 pre-adipocytes.

  7. A new prenylated indole diketopiperazine alkaloid from Eurotium cristatum.

    Science.gov (United States)

    Zou, Xianwei; Li, Ying; Zhang, Xiaona; Li, Qian; Liu, Xuan; Huang, Yun; Tang, Tao; Zheng, Saijing; Wang, Weimiao; Tang, Jintian

    2014-11-03

    A new prenylated indole diketopiperazine alkaloid, cristatumin F (1), and four known metabolites, echinulin (2), dehydroechinulin (3), neoechinulin A (4) and variecolorin O (5), were isolated from the crude extract of the fungus Eurotium cristatum. The structure of 1 was elucidated primarily by NMR and MS methods. The absolute configuration of 1 was assigned using Marfey's method applied to its acid hydrolyzate. Cristatumin F (1) showed modest radical scavenging activity against DPPH radicals, and exhibited marginal attenuation of 3T3L1 pre-adipocytes.

  8. First total synthesis of two nematicidal prenylated flavanones

    Institute of Scientific and Technical Information of China (English)

    Jin Hui Yang; Shi Zhi Jiang; Yan Min Zhao; Yun Feng Li; Cong Bin Ji; Wan Yi Liu

    2009-01-01

    The total synthesis of(±)-8-(3-methylbut-2-enyl)-2-phenyl-2,3-dihydrochromen-4-one and(±)-2-(4-hydroxyphenyl)-8-(3-methylbut-2-enyl)-2,3-dihydrochromen-4-one was first achieved through C-prenylation,protection of phenolic hydroxyl group,aldol condensation,cyclization and deprotection starting from cheap benzaldehyde,4-hydroxybenzaldehyde and 2-hydroxyacetophenone,with total yield of 20 and 16.3%.All structures of new compounds were confirmed by IR,1H NMR and MS.

  9. OSTEOPOROSIS IN CALCIUM PYROPHOSPHATE CRYSTAL DEPOSITION DISEASE

    Directory of Open Access Journals (Sweden)

    S A Vladimirov

    2013-01-01

    Full Text Available Objective: to study the incidence of osteoporosis (OP in patients with calcium pyrophosphate crystal deposition disease (CPCDD. Subjects and methods. Eighty patients with CPCDD were examined. Bone mineral density (BMD of the forearm, lumbar spine, and femoral neck was determined by dual-energy X-ray absorptiometry. Laboratory diagnosis involved determination of the blood levels of C-reactive protein, parathyroid hormone, calcium, magnesium, and phosphorus and the daily urinary excretion of calcium and phosphates. Results. The patients with OP were significantly older than those with normal BMD and osteopenia. Forearm bones were the most common isolated location of OP and osteopenia. Injuries in the history, traumatic fractures, and the intake of diuretics were somewhat more common in the patients diagnosed with OP. The incidence of hyperparathyroidism did not differ significantly in the groups.

  10. Calcium pyrophosphate deposition disease: clinical manifestations

    Directory of Open Access Journals (Sweden)

    M.A. Cimmino

    2012-01-01

    Full Text Available Calcium pyrophosphate deposition (CPPD disease is an arthropathy caused by calcium pyrophosphate dihydrate (CPP crystal deposits in articular tissues, most commonly fibrocartilage and hyaline cartilage. According to EULAR, four different clinical presentations can be observed: 1 asymptomatic CPPD; 2 osteoarthritis (OA with CPPD; 3 acute CPP crystal arthritis; 4 chronic CPP inflammatory crystal arthritis. Acute CPP crystal arthritis is characterized by sudden onset of pain, swelling and tenderness with overlying erythema, usually in a large joint, most often the knee, wrist, shoulder, and hip. Occasionally, ligaments, tendons, bursae, bone and the spine can be involved. CPPD of the atlanto-occipital joint (crowned dens syndrome can cause periodic acute cervico-occipital pain with fever, neck stiffness and laboratory inflammatory syndrome. Chronic inflammatory arthritis is characterized by joint swelling, morning stiffness, pain, and high ESR and CRP. The relationship between OA and CPPD is still unclear. The main problem is whether such crystals are directly involved in the pathogenesis of OA or if they are the result of joint degeneration. Diagnosis is based on evaluation of history and clinical features, conventional radiology, and synovial fluid examination. Non-polarized light microscopy should be used initially to screen for CPPD crystals based upon their characteristic morphology, and compensated polarized light microscopy, showing the crystals to be weakly positive birefringent, is recommended for definitive identification, although this last pattern only occurs in about 20% of samples. The main goals of CPPD therapy are control of the acute or chronic inflammatory reaction and prevention of further episodes.

  11. The emerging roles of inositol pyrophosphates in eukaryotic cell physiology

    Indian Academy of Sciences (India)

    Swarna Gowri Thota; Rashna Bhandari

    2015-09-01

    Inositol pyrophosphates are water soluble derivatives of inositol that contain pyrophosphate or diphosphate moieties in addition to monophosphates. The best characterised inositol pyrophosphates, are IP7 (diphosphoinositol pentakisphosphate or PP-IP5), and IP8 (bisdiphosphoinositol tetrakisphosphate or (PP)2-IP4). These energy-rich small molecules are present in all eukaryotic cells, from yeast to mammals, and are involved in a wide range of cellular functions including apoptosis, vesicle trafficking, DNA repair, osmoregulation, phosphate homeostasis, insulin sensitivity, immune signalling, cell cycle regulation, and ribosome synthesis. Identified more than 20 years ago, there is still only a rudimentary understanding of the mechanisms by which inositol pyrophosphates participate in these myriad pathways governing cell physiology and homeostasis. The unique stereochemical and bioenergetic properties these molecules possess as a consequence of the presence of one or two pyrophosphate moieties in the vicinity of densely packed monophosphates are likely to form the molecular basis for their participation in multiple signalling and metabolic pathways. The aim of this review is to provide first time researchers in this area with an introduction to inositol pyrophosphates and a comprehensive overview on their cellular functions.

  12. A new bioactive prenylated dihydroflavanoid from Dolichos tenuicaulis (Baker) Craib

    Institute of Scientific and Technical Information of China (English)

    Jin Yong Peng; Hai Yan Liu; Yan Qi; Xu Han; You Wei Xu; Li Na Xu; Qi Wei Xu

    2007-01-01

    A new prenylated dihydroflavonoid was obtained from the root of Dolichos tenuicaulis (Baker) Craib. The structure was elucidated as (2S)-5,2',6'-trihydroxy-3''', 8-di (γ, γ-dimethyl-allyl)-2''', 2'''-dimethylpyrano-[5''',6''':6,7]-2''''',4'''''-cyclohexadiene-1'''''-one-[2''''',3''''': 3',4']-flavanone, named dolichnin A, by spectroscopic methods including UV, IR, HR-EI-MS, 1D NMR and 2D NMR techniques, and subsequently, the anticancer activity of this compound to inhibit human cancer cells' growth including A549, BEL-7402, Hep-3B, SMMC7721, HT-29, MCF-7, SGC-7902, K562, A498 and PC3 cell lines by MTT method was evaluated in vitro.

  13. A New Prenylated Xanthone from Latex of Garcinia cowa Roxb.

    Directory of Open Access Journals (Sweden)

    Zhi Na

    2013-05-01

    Full Text Available A new prenylated xanthone, 1,6-dihydroxy-3,7-dimethoxy-2-(3,7-dimethyloct-2,6-dienyl xanthone (3-O-methylcowaxanthone (1, together with four known xanthones, cowaxanthone (2, 7-O-methylgarcinone (3, α-mangostin (4 and γ-mangostin (5 were isolated from the latex of Garcinia cowa. The structure of compound 1 was elucidated on the basis of spectroscopic data interpretation, including 1D and 2D NMR and HREIMS. The cytotoxic activitiy of 1 against five human cancer cell lines, HL-60, SMMC-7721, A-549, MCF-7 and SW480, was evaluated, but it was inactive (IC 50>40μM.

  14. Putative pyrophosphate phosphofructose 1-kinase genes identified in sugar cane may be getting energy from pyrophosphate.

    Science.gov (United States)

    Suzuki, J; Mutton, M A; Ferro, M I T; Lemos, M V F; Pizauro, J M; Mutton, M J R; Di Mauro, S M Z

    2003-12-30

    Pyrophosphate-dependent phosphofructokinase (PPi-PFK) has been detected in several types of plant cells, but the gene has not been reported in sugar cane. Using Citrus paradisi PPi-PFK gene (AF095520 and AF095521) sequences to search the sugar cane EST database, we have identified both the alpha and beta subunits of this enzyme. The deduced amino acid sequences showed 76 and 80% similarity with the corresponding alpha and beta subunits of C. paradisi. A high degree of similarity was also observed among the PFK b subunits when the alignment of the sugar cane sequences was compared to those of Ricinus communis and Solanum tuberosum. It appears that alpha and beta are two distinct subunits; they were found at different concentrations in several sugar cane tissues. It remains to be determined if the different gene expression levels have some physiological importance and how they affect sucrose synthesis, export, and storage in vacuoles. A comparison between the amino acid sequences of b PFKs from a variety of organisms allowed us to identify the two critical Asp residues typical of this enzyme's activity site and the other binding sites; these residues are tightly conserved in all members of this protein family. Apparently, there are catalytic residues on the b subunit of the pyrophosphate-dependent enzyme.

  15. PRENYLATED BENZOIC ACID DERIVATIVES FROM PIPER SPECIES AS SOURCE OF ANTI-INFECTIVE AGENTS

    OpenAIRE

    2012-01-01

    A number of prenylated benzoic acids derivatives with interesting biological activities have been previously isolated and characterized from different species of piperaceae family. Several Piper species contained structurally similar compounds with diverse biological activities such as anti-bacterial, anti-fungal, insecticidal as well as anti-parasitic all of which produces compounds that can be classified as prenylated benzoic acid derivatives. Piper sp has proven to serve as a source of pot...

  16. Strategies for the Preparation of Differentially Protected ortho-Prenylated Phenols.

    Science.gov (United States)

    Hoarau, Christophe; Pettus, Thomas R R

    2003-01-01

    A new process for ortho-prenylation of phenols is presented within the context of known methods. All of the processes are briefly assessed with regards to the substitution patterns and accompanying functional groups tolerated by each strategy. The conclusion reached is that a new procedure using ortho-quinone methides, for which an experimental protocol is provided, offers the greatest generality and flexibility in the preparation of ortho-prenylated phenol derivatives.

  17. The ANKH gene and familial calcium pyrophosphate dihydrate deposition disease.

    Science.gov (United States)

    Netter, Patrick; Bardin, Thomas; Bianchi, Arnaud; Richette, Pascal; Loeuille, Damien

    2004-09-01

    Familial calcium pyrophosphate dihydrate deposition (CPPD) disease is a chronic condition in which CPPD microcrystals deposit in the joint fluid, cartilage, and periarticular tissues. Two forms of familial CPPD disease have been identified: CCAL1 and CCAL2. The CCAL1 locus is located on the long arm of chromosome 8 and is associated with CPPD and severe osteoarthritis. The CCAL2 locus has been mapped to the short arm of chromosome 5 and identified in families from the Alsace region of France and the United Kingdom. The ANKH protein is involved in pyrophosphate metabolism and, more specifically, in pyrophosphate transport from the intracellular to the extracellular compartment. Numerous ANKH gene mutations cause familial CCAL2; they enhance ANKH protein activity, thereby elevating extracellular pyrophosphate levels and promoting the formation of pyrophosphate crystals, which produce the manifestations of the disease. Recent studies show that growth factors and cytokines can modify the expression of the normal ANKH protein. These results suggest a role for ANKH in sporadic CPPD disease and in CPPD associated with degenerative disease.

  18. Modification of Prenylated Stilbenoids in Peanut (Arachis hypogaea) Seedlings by the Same Fungi That Elicited Them: The Fungus Strikes Back.

    Science.gov (United States)

    Aisyah, Siti; Gruppen, Harry; Slager, Mathijs; Helmink, Bianca; Vincken, Jean-Paul

    2015-10-28

    Aspergillus oryzae and Rhizopus oryzae were compared for inducing the production of prenylated stilbenoids in peanut seedlings. The fungus was applied at two different time points: directly after soaking (day 1) or after 2 days of germination (day 3). Aspergillus- and Rhizopus-elicited peanut seedlings accumulated an array of prenylated stilbenoids, with overlap in compounds induced, but also with compounds specific to the fungal treatment. The differences were confirmed to be due to modification of prenylated stilbenoids by the fungus itself. Each fungus appeared to deploy different strategies for modification. The content of prenylated stilbenoids modified by fungi accounted for around 8% to 49% (w/w) of total stilbenoids. The contents of modified prenylated stilbenoids were higher when the fungus was applied on day 1 instead of day 3. Altogether, type of fungus and time point of inoculation appeared to be crucial parameters for optimizing accumulation of prenylated stilbenoids in peanut seedlings.

  19. Antiherbivore prenylated benzoic acid derivatives from Piper kelleyi.

    Science.gov (United States)

    Jeffrey, Christopher S; Leonard, Michael D; Glassmire, Andrea E; Dodson, Craig D; Richards, Lora A; Kato, Massuo J; Dyer, Lee A

    2014-01-24

    The known prenylated benzoic acid derivative 3-geranyl-4-hydroxy-5-(3″,3″-dimethylallyl)benzoic acid (1) and two new chromane natural products were isolated from the methanolic extract of the leaves of Piper kelleyi Tepe (Piperaceae), a midcanopy tropical shrub that grows in lower montane rain forests in Ecuador and Peru. Structure determination using 1D and 2D NMR analysis led to the structure of the chromene 2 and to the reassignment of the structure of cumanensic acid as 4, an isomeric chromene previously isolated from Piper gaudichaudianum. The structure and relative configuration of new chromane 3 was determined using 1D and 2D NMR spectroscopic analysis and was found to be racemic by ECD spectropolarimetry. The biological activity of 1-3 was evaluated against a lab colony of the generalist caterpillar Spodoptera exigua (Noctuidae), and low concentrations of 2 and 3 were found to significantly reduce fitness. Further consideration of the biosynthetic relationship of the three compounds led to the proposal that 1 is converted to 2 via an oxidative process, whereas 3 is produced through hetero-[4+2] dimerization of a quinone methide derived from the chromene 2.

  20. Synthesis of pyrophosphonic acid analogues of farnesyl pyrophosphate

    NARCIS (Netherlands)

    Valentijn, A.R.P.M.; Berg, O. van den; Marel, G.A. van der; Cohen, L.H.; Boom, J.H. van

    1995-01-01

    The synthesis of four new analogues (i.e. 3-6) of farnesyl pyrophosphate (FPP), which may function as inhibitor of squalene synthase, is described. Compounds 3 and 4 were readily accessible by reaction of farnesal with diethyl phosphite or dimethyl lithiomethylphosphonate, respectively, followed by

  1. Evaluation of myocardial revascularization utilizing Tc-99m pyrophosphate.

    Science.gov (United States)

    Liddicoat, J E; Bekassy, S M; Johnson, P C; Ajmani, S K; DeBakey, M E

    1974-01-01

    Early clinical application of technetium 99m labeled pyrophosphate for cardiac imaging has revealed a safe noninvasive method of determining areas of impaired myocardial perfusion in patients with atherosclerotic occlusive coronary artery disease. Using this method, we were able to demonstrate improvement in myocardial blood supply following coronary artery bypass surgery.

  2. Structural basis for an inositol pyrophosphate kinase surmounting phosphate crowding

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Huanchen; Falck, J.R.; Hall, Traci M. Tanaka; Shears, Stephen B. (NIH); (UTSMC)

    2012-01-11

    Inositol pyrophosphates (such as IP7 and IP8) are multifunctional signaling molecules that regulate diverse cellular activities. Inositol pyrophosphates have 'high-energy' phosphoanhydride bonds, so their enzymatic synthesis requires that a substantial energy barrier to the transition state be overcome. Additionally, inositol pyrophosphate kinases can show stringent ligand specificity, despite the need to accommodate the steric bulk and intense electronegativity of nature's most concentrated three-dimensional array of phosphate groups. Here we examine how these catalytic challenges are met by describing the structure and reaction cycle of an inositol pyrophosphate kinase at the atomic level. We obtained crystal structures of the kinase domain of human PPIP5K2 complexed with nucleotide cofactors and either substrates, product or a MgF{sub 3}{sup -} transition-state mimic. We describe the enzyme's conformational dynamics, its unprecedented topological presentation of nucleotide and inositol phosphate, and the charge balance that facilitates partly associative in-line phosphoryl transfer.

  3. Synthesis of pyrophosphonic acid analogues of farnesyl pyrophosphate

    NARCIS (Netherlands)

    Valentijn, A.R.P.M.; Berg, O. van den; Marel, G.A. van der; Cohen, L.H.; Boom, J.H. van

    1995-01-01

    The synthesis of four new analogues (i.e. 3-6) of farnesyl pyrophosphate (FPP), which may function as inhibitor of squalene synthase, is described. Compounds 3 and 4 were readily accessible by reaction of farnesal with diethyl phosphite or dimethyl lithiomethylphosphonate, respectively, followed by

  4. Evaluation of a cell penetrating prenylated peptide lacking an intrinsic fluorophore via in situ click reaction.

    Science.gov (United States)

    Ochocki, Joshua D; Mullen, Daniel G; Wattenberg, Elizabeth V; Distefano, Mark D

    2011-09-01

    Protein prenylation involves the addition of either a farnesyl (C(15)) or geranylgeranyl (C(20)) isoprenoid moiety onto the C-terminus of many proteins. This natural modification serves to direct a protein to the plasma membrane of the cell. A recently discovered application of prenylated peptides is that they have inherent cell-penetrating ability, and are hence termed cell penetrating prenylated peptides. These peptides are able to efficiently cross the cell membrane in an ATP independent, non-endocytotic manner and it was found that the sequence of the peptide does not affect uptake, so long as the geranylgeranyl group is still present [Wollack, J. W.; Zeliadt, N. A.; Mullen, D. G.; Amundson, G.; Geier, S.; Falkum, S.; Wattenberg, E. V.; Barany, G.; Distefano, M. D. Multifunctional Prenylated Peptides for Live Cell Analysis. J. Am. Chem. Soc.2009, 131, 7293-7303]. The present study investigates the effect of removing the fluorophore from the peptides and investigating the uptake by confocal microscopy and flow cytometry. Our results show that the fluorophore is not necessary for uptake of these peptides. This information is significant because it indicates that the prenyl group is the major determinant in allowing these peptides to enter cells; the hydrophobic fluorophore has little effect. Moreover, these studies demonstrate the utility of the Cu-catalyzed click reaction for monitoring the entry of nonfluorescent peptides into cells.

  5. Differential effects of prenylation and s-acylation on type I and II ROPS membrane interaction and function.

    Science.gov (United States)

    Sorek, Nadav; Gutman, Orit; Bar, Einat; Abu-Abied, Mohamad; Feng, Xuehui; Running, Mark P; Lewinsohn, Efraim; Ori, Naomi; Sadot, Einat; Henis, Yoav I; Yalovsky, Shaul

    2011-02-01

    Prenylation primarily by geranylgeranylation is required for membrane attachment and function of type I Rho of Plants (ROPs) and Gγ proteins, while type II ROPs are attached to the plasma membrane by S-acylation. Yet, it is not known how prenylation affects ROP membrane interaction dynamics and what are the functional redundancy and specificity of type I and type II ROPs. Here, we have used the expression of ROPs in mammalian cells together with geranylgeranylation and CaaX prenylation-deficient mutants to answer these questions. Our results show that the mechanism of type II ROP S-acylation and membrane attachment is unique to plants and likely responsible for the viability of plants in the absence of CaaX prenylation activity. The prenylation of ROPs determines their steady-state distribution between the plasma membrane and the cytosol but has little effect on membrane interaction dynamics. In addition, the prenyl group type has only minor effects on ROP function. Phenotypic analysis of the CaaX prenylation-deficient pluripetala mutant epidermal cells revealed that type I ROPs affect cell structure primarily on the adaxial side, while type II ROPs are functional and induce a novel cell division phenotype in this genetic background. Taken together, our studies show how prenyl and S-acyl lipid modifications affect ROP subcellular distribution, membrane interaction dynamics, and function.

  6. Dissolution behaviour of ferric pyrophosphate and its mixtures with soluble pyrophosphates: Potential strategy for increasing iron bioavailability.

    Science.gov (United States)

    Tian, Tian; Blanco, Elena; Smoukov, Stoyan K; Velev, Orlin D; Velikov, Krassimir P

    2016-10-01

    Ferric pyrophosphate (FePP) is a widely used iron source in food fortification and in nutritional supplements, due to its white colour, that is very uncommon for insoluble Fe salts. Although its dissolution is an important determinant of Fe adsorption in human body, the solubility characteristics of FePP are complex and not well understood. This report is a study on the solubility of FePP as a function of pH and excess of pyrophosphate ions. FePP powder is sparingly soluble in the pH range of 3-6 but slightly soluble at pH8. In the presence of pyrophosphate ions the solubility of FePP strongly increases at pH 5-8.5 due to formation a soluble complex between Fe(III) and pyrophosphate ions, which leads to an 8-10-fold increase in the total ionic iron concentration. This finding is beneficial for enhancing iron bioavailability, which important for the design of fortified food, beverages, and nutraceutical products.

  7. Circadian rhythm of anti-fungal prenylated chromene in leaves of Piper aduncum.

    Science.gov (United States)

    Morandim, Andreia de A; Bergamo, Débora Cristina B; Kato, Massuo Jorge; Cavalheiro, Alberto José; Bolzani, Vanderlan da S; Furlan, Maysa

    2005-01-01

    Leaves of Piper aduncum accumulate the anti-fungal chromenes methyl 2,2-dimethyl-2H-1-chromene-6-carboxylate (1) and methyl 2,2-dimethyl-8-(3'-methyl-2'-butenyl)-2H-1-chromene-6-carboxylate (2). The enzymatic formation of 2 from dimethylallyl diphosphate and 1 was investigated using cell-free extracts of the title plant. An HPLC assay for the prenylation reaction was developed and the enzyme activity measured in the protein extracts. The prenyltransferase that catalyses the transfer of the dimethylallyl group to C-2' of 1 was soluble and required dimethylallyl diphosphate as the prenyl donor. In the leaves, the biosynthesis of the prenylated chromene 2 was time-regulated and prenyltransferase activity depended upon circadian variation. Preliminary characterisation and purification experiments on the prenyltransferase from P. aduncum have been performed.

  8. PRENYLATED BENZOIC ACID DERIVATIVES FROM PIPER SPECIES AS SOURCE OF ANTI-INFECTIVE AGENTS

    Directory of Open Access Journals (Sweden)

    Ibrahim Malami

    2012-06-01

    Full Text Available A number of prenylated benzoic acids derivatives with interesting biological activities have been previously isolated and characterized from different species of piperaceae family. Several Piper species contained structurally similar compounds with diverse biological activities such as anti-bacterial, anti-fungal, insecticidal as well as anti-parasitic all of which produces compounds that can be classified as prenylated benzoic acid derivatives. Piper sp has proven to serve as a source of potential anti-infective agents by developing a biosynthetic route to the synthesis of prenylated benzoic acids derivative natural products as their chemical defense system. Despite the frequent isolation of these interesting compounds with strong biological activity, yet none have been taking into consideration for development into therapeutic agents.

  9. Statin treatment increases lifespan and improves cardiac health in Drosophila by decreasing specific protein prenylation.

    Directory of Open Access Journals (Sweden)

    Stephen R Spindler

    Full Text Available Statins such as simvastatin are 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA reductase inhibitors and standard therapy for the prevention and treatment of cardiovascular diseases in mammals. Here we show that simvastatin significantly increased the mean and maximum lifespan of Drosophila melanogaster (Drosophila and enhanced cardiac function in aging flies by significantly reducing heart arrhythmias and increasing the contraction proportion of the contraction/relaxation cycle. These results appeared independent of internal changes in ubiquinone or juvenile hormone levels. Rather, they appeared to involve decreased protein prenylation. Simvastatin decreased the membrane association (prenylation of specific small Ras GTPases in mice. Both farnesyl (L744832 and type 1 geranylgeranyl transferase (GGTI-298 inhibitors increased Drosophila lifespan. These data are the most direct evidence to date that decreased protein prenylation can increase cardiac health and lifespan in any metazoan species, and may explain the pleiotropic (non-cholesterol related health effects of statins.

  10. A new prenylated flavanonol from Seseli annuum roots showing protective effect on human lymphocytes DNA.

    Science.gov (United States)

    Vucković, Ivan; Vajs, Vlatka; Stanković, Miroslava; Tesević, Vele; Milosavljević, Slobodan

    2010-03-01

    A new prenylated flavanonol named seselinonol (1) was isolated from the roots of Seseli annuum, together with the well-known biologically active polyacetylenes falcarinol (2) and falcarindiol (3), and the prenylated furanocoumarin phellopterin (4). Its structure was elucidated by extensive spectroscopic analysis, including HR-ESI-MS, 1D- and 2D-NMR. Seselinonol and phellopterin were tested for in vitro protective effect on chromosome aberrations in peripheral human lymphocytes using cytochalasin-B blocked micronucleus (CBMN) assay. The new compound exerted a beneficial effect by decreasing DNA damage of human lymphocytes.

  11. Calcium pyrophosphate crystal deposition disease: diagnosis and treatment

    Directory of Open Access Journals (Sweden)

    Rosales-Alexander JL

    2014-05-01

    Full Text Available José Luis Rosales-Alexander,1 Jerónimo Balsalobre Aznar,1 César Magro-Checa2 1Rheumatology Department, Hospiten Ramblas, Santa Cruz de Tenerife, 2Rheumatology Department, San Cecilio University Hospital, Granada, Spain Abstract: Calcium pyrophosphate dihydrate crystal deposition disease (CPPD is an inflammatory arthritis produced by the deposition of calcium pyrophosphate (CPP crystals in the synovium and periarticular soft tissues. It is the third most common inflammatory arthritis. Diagnosis is suspected on the basis of the clinical picture and radiographic/laboratory findings. The reference standard for the diagnosis of CPPD is based on the identification of CPP crystals in synovial fluid by light microscopy, compensated polarized light microscopy, or phase contrast microscopy. Most treatment approaches for CPPD are based upon clinical experience and not upon controlled trials. They range – depending on the subtype and the characteristics of symptoms – from no treatment to interleukin-1 blockade antibodies or specific therapy for an underlying disease. This review summarizes all we know so far about the diagnosis and management of CPPD. Keywords: calcium pyrophosphate dihydrate deposition disease, CPPD, chondrocalcinosis, crystal-induced arthritides

  12. A Brief Review on Calcium Pyrophosphate Deposition Disease (Pseudogout

    Directory of Open Access Journals (Sweden)

    Manoj A. Suva

    2014-08-01

    Full Text Available Calcium pyrophosphate deposition disease (CPDD or pseudo gout is a metabolic arthropathy caused by the deposition of calcium pyrophosphate dihydrate in and around joints especially in articular cartilage and fibro cartilage. Pseudo gout is a joint disease that can cause attacks of arthritis. Like gout, the condition involves the formation of crystals in the joints. But in pseudo gout, the crystals are formed from a salt instead of uric acid. Almost any joint may be involved by CPDD, although the knees, wrists, and hips are most often affected. Exact mechanism for the development of CPDD is still not known, but increased adenosine triphosphate breakdown which leads to increased inorganic pyrophosphate in the joints results from aging, genetic factors, or both. CPDD is a common condition that occurs with aging in all races. About 50% of people above 85 years have chondrocalcinosis in the United States. Physical examination findings show an acutely inflamed joint with swelling, effusion, warmth, tenderness and pain on motion similar to acute gouty arthritis and occur in the knee but may be present in the wrists, shoulders, ankles, hands and feet. Laboratory tests include serum calcium, phosphorus and magnesium, alkaline phosphatase levels, iron levels, total iron binding capacity, transferrin saturation and ferritin, thyroid-stimulating hormone and free thyroxine levels. Imaging studies like radiography, magnetic resonance imaging (MRI and Ultrasonography is done. Management of CPPD includes surgery and pharmacotherapy with Nonsteroidal anti-inflammatory drugs (NSAIDs, anti-inflammatory agents like colchicine and corticosteroids such as prednisone and methylprednisolone.

  13. Antiparasitic activity of prenylated benzoic acid derivatives from Piper species.

    Science.gov (United States)

    Flores, Ninoska; Jiménez, Ignacio A; Giménez, Alberto; Ruiz, Grace; Gutiérrez, David; Bourdy, Genevieve; Bazzocchi, Isabel L

    2009-03-01

    Fractionation of dichloromethane extracts from the leaves of Piper heterophyllum and P. aduncum afforded three prenylated hydroxybenzoic acids, 3-[(2E,6E,10E)-11-carboxy-3,7,15-trimethyl-2,6,10,14-hexadecatetraenyl)-4,5-dihydroxybenzoic acid, 3-[(2E,6E,10E)-11-carboxy-13-hydroxy-3,7,15-trimethyl-2,6,10,14-hexadecatetraenyl]-4,5-dihydroxybenzoic acid and 3-[(2E,6E,10E)-11-carboxy-14-hydroxy-3,7,15-trimethyl-2,6,10,15-hexadecatetraenyl]-4,5-dihydroxybenzoic acid, along with the known compounds, 4,5-dihydroxy-3-(E,E,E-11-formyl-3,7,15-trimethyl-hexadeca-2,6,10,14-tetraenyl)benzoic acid (arieianal), 3,4-dihydroxy-5-(E,E,E-3,7,11,15-tetramethyl-hexadeca-2,6,10,14-tetraenyl)benzoic acid, 4-hydroxy-3-(E,E,E-3,7,11,15-tetramethyl-hexadeca-2,6,10,14-tetraenyl)benzoic acid, 3-(3,7-dimethyl-2,6-octadienyl)-4-methoxy-benzoic acid, 4-hydroxy-3-(3,7-dimethyl-2,6-octadienyl)benzoic acid and 4-hydroxy-3-(3-methyl-1-oxo-2-butenyl)-5-(3-methyl-2-butenyl)benzoic acid. Their structures were elucidated on the basis of spectroscopic data, including homo- and heteronuclear correlation NMR experiments (COSY, HSQC and HMBC) and comparison with data reported in the literature. Riguera ester reactions and optical rotation measurements established the compounds as racemates. The antiparasitic activity of the compounds were tested against three strains of Leishmania spp., Trypanosoma cruzi and Plasmodium falciparum. The results showed that 3-(3,7-dimethyl-2,6-octadienyl)-4-methoxy-benzoic acid exhibited potent and selective activity against L. braziliensis (IC(50) 6.5 microg/ml), higher that pentamidine used as control. Moreover, 3-[(2E,6E,10E)-11-carboxy-3,7,15-trimethyl- 2,6,10,14-hexadecatetraenyl)-4,5-dihydroxybenzoic acid and 4-hydroxy-3-(3-methyl-1-oxo-2-butenyl)-5-(3-methyl-2-butenyl)benzoic acid showed moderate antiplasmodial (IC(50) 3.2 microg/ml) and trypanocidal (16.5 microg/ml) activities, respectively.

  14. Prenylated isoflavonoids from soya and licorice : analysis, induction and in vitro estrogenicity

    NARCIS (Netherlands)

    Simons, R.

    2011-01-01


    Prenylatedisoflavonoids are found in large amountsin soya bean (Glycine max) germinated under stress and in licorice (Glycyrrhiza glabra). Prenylation of isoflavonoids has been associated with modification of theirestrogenic activity.
    The aims of this thesis were (1) to provide a struct

  15. Prenylated isoflavonoids from soya and licorice : analysis, induction and in vitro estrogenicity

    NARCIS (Netherlands)

    Simons, R.

    2011-01-01


    Prenylatedisoflavonoids are found in large amountsin soya bean (Glycine max) germinated under stress and in licorice (Glycyrrhiza glabra). Prenylation of isoflavonoids has been associated with modification of theirestrogenic activity.
    The aims of this thesis were (1) to provide a

  16. How prenylation and S-acylation regulate subcellular targeting and function of ROP GTPases.

    Science.gov (United States)

    Sorek, Nadav; Henis, Yoav I; Yalovsky, Shaul

    2011-07-01

    Rho of Plants (ROP) small G proteins function at discrete domains of the plasma and possibly endo membranes. ROPs are synthesized as soluble proteins and their attachment to membranes and partitioning in membrane microdomains are facilitated by the posttranslational lipid modifications prenylation and/or S-acylation. Based on their amino acid sequences, ROPs can be classified into two major subgroups: type-I ROPs terminate with a canonical CaaX box motif and are prenylated primarily by geranylgeranyltransferase-I (GGT-I) and to a lesser extent by farnesyltransferase (FT). Type-II ROPs terminate with a plant specific GC-CG box domain and are attached to the plasma membrane by stable S-acylation. In addition, type-I and possibly also type-II ROPs undergo activation dependent transient S-acylation in the G-domain and consequent partitioning into lipid rafts. Surprisingly, although geranylgeranylation is required for the membrane attachment of type-I ROPs and the γ subunits of heterotrimeric G proteins, Arabidopsis mutants lacking GGT-I function have a mild phenotype compared to wild type plants. The mild phenotype of the ggt-I mutants suggested that farnesylation by FT may compensate for the loss of GGT-I function and that possibly the prenylated type-I and S-acylated type-II ROPS have some overlapping functions. In a paper recently published in Plant Physiology we examined the role of the prenyl group type in type-I ROP function and membrane interaction dynamics and the functional redundancy between type-I and type-II ROPs. This study complements a second paper in which we examined the role of G-domain transient S-acylation in the membrane interaction dynamics and signaling by type-I ROPs. Together these two studies provide a framework for realizing the role of prenylation and S-acylation in subcellular targeting, membrane interaction dynamics and signaling by ROP GTPases.

  17. Thiamine pyrophosphate (cocarboxylase) as a growth factor for Haemophilus somnus.

    OpenAIRE

    Asmussen, M D; Baugh, C. L.

    1981-01-01

    The effect of a commercially available, chemically defined enrichment (Iso-VitaleX; BBL Microbiology Systems, Cockeysville, Md.) on the growth of 10 strains of Haemophilus somnus was studied. A 6- to 10-fold increase in growth, as measured turbidimetrically, was observed when Iso VitaleX was added to a basal medium of brain heart infusion broth to a final concentration of 1% (vol/vol). Thiamine pyrophosphate (cocarboxylase), a constituent component of Iso VitaleX, was found to be the only gro...

  18. Biosynthesis and possible functions of inositol pyrophosphates in plants

    OpenAIRE

    Sarah Phoebe Williams; Glenda E. Gillaspy; Imara Yasmin Perera

    2015-01-01

    Inositol phosphates (InsPs) are intricately tied to lipid signaling, as at least one portion of the inositol phosphate signaling pool is derived from hydrolysis of the lipid precursor, phosphatidyl inositol (4,5) bisphosphate. The focus of this review is on the inositol pyrophosphates, which are a novel group of InsP signaling molecules containing diphosphate or triphosphate chains (i.e., PPx) attached to the inositol ring. These PPx-InsPs are emerging as critical players in the integration o...

  19. Inositol pyrophosphates and their unique metabolic complexity: analysis by gel electrophoresis.

    Directory of Open Access Journals (Sweden)

    Oriana Losito

    Full Text Available BACKGROUND: Inositol pyrophosphates are a recently characterized cell signalling molecules responsible for the pyrophosphorylation of protein substrates. Though likely involved in a wide range of cellular functions, the study of inositol pyrophosphates has suffered from a lack of readily available methods for their analysis. PRINCIPAL FINDING: We describe a novel, sensitive and rapid polyacrylamide gel electrophoresis (PAGE-based method for the analysis of inositol pyrophosphates. Using 4',6-diamidino-2-phenylindole (DAPI and Toluidine Blue we demonstrate the unequivocal detection of various inositol pyrophosphate species. CONCLUSION: The use of the PAGE-based method reveals the likely underestimation of inositol pyrophosphates and their signalling contribution in cells when measured via traditional HPLC-based techniques. PAGE-based analyses also reveals the existence of a number of additional, previously uncharacterised pyrophosphorylated inositol reaction products, defining a more complex metabolism associated with the catalytically flexible kinase class responsible for the production of these highly energetic cell signalling molecules.

  20. Xanthohumol, a prenylated chalcone from Humulus lupulus L., inhibits cholesteryl ester transfer protein.

    Science.gov (United States)

    Hirata, Hiroshi; Takazumi, Koji; Segawa, Shuichi; Okada, Yukio; Kobayashi, Naoyuki; Shigyo, Tatsuro; Chiba, Hitoshi

    2012-10-01

    High density lipoprotein (HDL)-cholesterol levels are correlated with a low risk of atherosclerosis. The inhibition of cholesteryl ester transfer protein (CETP), which catalyses cholesterol transfer between lipoproteins, leads to an increase in HDL-cholesterol and is expected to be the next anti-atherogenic target. This study revealed that xanthohumol, a prenylated chalcone, showed the highest inhibition against CETP from screening of natural products in various plants. We investigated the inhibitory activity of some chalcones and flavanones. Naringenin chalcone showed weak CETP inhibition compared with xanthohumol. In addition, isoxanthohumol and naringenin drastically decreased the inhibitory activity. These results suggest that the prenyl group and chalcone structure of xanthohumol were responsible for the CETP inhibitory activity.

  1. Synthesis of the naturally occurring prenylated coumarins balsamiferone and cedrelopsin by domino reactions

    Digital Repository Service at National Institute of Oceanography (India)

    Patre, R.E.; Parameswaran, P.S.; Tilve, S.G.

    = Prenyl 6c, R = Benzyl 8, R = Allyl 2, R = Prenyl 9, R = Benzyl Scheme 1 OH OO R O O COOEt R (3,3) (3,3) O O COOEt R H 7 11 12 Scheme 2 Kapil et al. 12 have synthesized balsamiferone 2 beginning from umbelliferone-3-carboxylic acid in 13....04, 165.33, 188.39; 1 H NMR (300 MHz, CDCl 3 ) δ 1.76 (3H, s, CH 3 ), 1.77 (3H, s, CH 3 ), 1.82 (6H, s, 2 X CH 3 ), 4.59 (4H, m, CH 2 ), 5.50 (2H, m, CH), 6.48 (1H, s, H-3), 6.54 (1H, d, J = 8.7 Hz, H-5), 7.80 (1H, d, J = 8.7 Hz, H-6), 10.32 (1H, s...

  2. Prenylated flavonoids from the roots of Desmodium caudatum and evaluation of their antifungal activity.

    Science.gov (United States)

    Sasaki, Hisako; Kashiwada, Yoshiki; Shibatav, Hirofumi; Takaishi, Yoshihisa

    2012-11-01

    Two new prenylated flavonoids (1, 4) and two new prenylated C-methyl-flavonoids (6, 7), together with four known flavonoids (2, 3, 5, 8), were isolated from the roots of Desmodium caudatum. The structures of the new compounds were elucidated by extensive spectroscopic analyses including 1D-, 2D-NMR and MS. The antifungal activities of five compounds (1, 2, 4, 6, 8) as well as nine flavonoids (9-17) previously isolated from this plant against Aspergillus niger, Penicillium sp., Rhizopus sp., and Trichophyton sp. were evaluated. Compound 6 showed potent antifungal activity against Trichophyton sp. with a minimum inhibitory concentration (MIC) value of 1.95 µg/mL.

  3. Rho-A prenylation and signaling link epithelial homeostasis to intestinal inflammation

    DEFF Research Database (Denmark)

    López-Posadas, Rocío; Becker, Christoph; Günther, Claudia

    2016-01-01

    the transcriptome of IECs from IBD patients using a genome-wide approach. We observed disease-specific alterations in IECs with markedly impaired Rho-A signaling in active IBD patients. Localization of epithelial Rho-A was shifted to the cytosol in IBDs, and inflammation was associated with suppressed Rho......-A activation due to reduced expression of the Rho-A prenylation enzyme geranylgeranyltransferase-I (GGTase-I). Functionally, we found that mice with conditional loss of Rhoa or the gene encoding GGTase-I, Pggt1b, in IECs exhibit spontaneous chronic intestinal inflammation with accumulation of granulocytes...... and CD4+ T cells. This phenotype was associated with cytoskeleton rearrangement and aberrant cell shedding, ultimately leading to loss of epithelial integrity and subsequent inflammation. These findings uncover deficient prenylation of Rho-A as a key player in the pathogenesis of IBDs. As therapeutic...

  4. Micro-RNA quantification using DNA polymerase and pyrophosphate quantification.

    Science.gov (United States)

    Yu, Hsiang-Ping; Hsiao, Yi-Ling; Pan, Hung-Yin; Huang, Chih-Hung; Hou, Shao-Yi

    2011-12-15

    A rapid quantification method for micro-RNA based on DNA polymerase activity and pyrophosphate quantification has been developed. The tested micro-RNA serves as the primer, unlike the DNA primer in all DNA sequencing methods, and the DNA probe serves as the template for DNA replication. After the DNA synthesis, the pyrophosphate detection and quantification indicate the existence and quantity of the tested miRNA. Five femtomoles of the synthetic RNA could be detected. In 20-100 μg RNA samples purified from SiHa cells, the measurement was done using the proposed assay in which hsa-miR-16 and hsa-miR-21 are 0.34 fmol/μg RNA and 0.71 fmol/μg RNA, respectively. This simple and inexpensive assay takes less than 5 min after total RNA purification and preparation. The quantification is not affected by the pre-miRNA which cannot serve as the primer for the DNA synthesis in this assay. This assay is general for the detection of the target RNA or DNA with a known matched DNA template probe, which could be widely used for detection of small RNA, messenger RNA, RNA viruses, and DNA. Therefore, the method could be widely used in RNA and DNA assays. Copyright © 2011 Elsevier Inc. All rights reserved.

  5. Probing riboswitch-ligand interactions using thiamine pyrophosphate analogues.

    Science.gov (United States)

    Chen, Liuhong; Cressina, Elena; Dixon, Neil; Erixon, Karl; Agyei-Owusu, Kwasi; Micklefield, Jason; Smith, Alison G; Abell, Chris; Leeper, Finian J

    2012-08-14

    The Escherichia coli thiM riboswitch forms specific contacts with its natural ligand, thiamine pyrophosphate (TPP or thiamine diphosphate), allowing it to generate not only nanomolar binding affinity, but also a high degree of discrimination against similar small molecules. A range of synthetic TPP analogues have been used to probe each of the riboswitch-ligand interactions. The results show that the pyrimidine-sensing helix of thiM is exquisitely tuned to select for TPP by recognising the H-bonding donor and acceptors around its aminopyrimidine ring and also by forming π-stacking interactions that may be sensitive to the electronics of the ring. The central thiazolium ring of TPP appears to be more important for ligand recognition than previously thought. It may contribute to binding via long-range electrostatic interactions and/or by exerting an electron withdrawing effect on the pyrimidine ring, allowing its presence to be sensed indirectly and thereby allowing discrimination between thiamine (and its phosphate esters) and other aminopyrimidines found in vivo. The pyrophosphate moiety is essential for submicromolar binding affinity, but unexpectedly, it does not appear to be strictly necessary for modulation of gene expression.

  6. Synthesis and Characterization of Nanoparticles of Calcium Pyrophosphate

    Science.gov (United States)

    Vasant, Sonal R.; Joshi, M. J.

    Calcium phosphate based biomaterials play important roles in clinical applications. Calcium pyrophosphate (CPP), a kind of calcium phosphate, can be used as a bone substitution material as well as a bone graft. Because of its similarity to inorganic component of bone and teeth it can be used for surface coating of metallic dental and orthopedic implants. In the present study, calcium pyrophosphate dihydrate (CPPD) nanoparticles were synthesized using surfactant mediated approach. Crystalline nature and average crystallite size was studied using Powder XRD. The CPPD nanocrystallites were found to be triclinic from powder XRD. The TEM study indicated that CPPD nanoparticles were in the range of 13 nm to 20 nm. The presence of various bonds was confirmed by FTIR spectroscopy. The amount of water of hydration and the thermal stability was studied by thermogravimetry. The variations of various dielectric parameters with the frequency of applied field in 3.2 kHz to 32 MHz range and within a temperature range from 60°C to 120°C were studied. The formation of other phases such as β-CPP and α-CPP on heating of CPPD at 900°C and 1250°C, respectively, were studied by the Powder XRD. The results are discussed.

  7. Aluminum Ion Removal from Monoaluminum Ovotransferrin by Pyrophosphate

    Institute of Scientific and Technical Information of China (English)

    LI,Ying-Qi(李英奇); YANG,Bin-Sheng(杨斌盛)

    2004-01-01

    The rates at which aluminum was removed from the N- and C-terminal monoaluminum ovotransferrins by pyrophosphate were evaluated by UV difference spectra in 0.01 mol/L Hepes, pH=7.4 and at 37 ℃. Pesudo first-order rate constants as a function of pyrophosphate concentration were measured. The results indicate that the pathways of aluminum removal are different. For the N-terminal binding site, aluminum removal follows simple saturation kinetics, while the removal of aluminum from the C-terminal binding site reverts to the combination of saturation and first-order kinetics. The saturation component is consistent with a rate-limiting conformational change in the protein as has been reported. We propose that the first-order kinetics mechanism is attributed to a pre-equilibrium process. The rate constants of saturation kinetics are accelerated from both terminals with the addition of 0.1 mol/L chloride to the monoaluminum ovotransferrin solutions, whereas the rates of the first-order kinetics are decreased for the C-terminal binding site. The effect of chloride ionic strength causes a continuing increase on kobs for the N- and C-terminal binding sites. Moreover, the kinetics behavior of the N-terminal is more easily affected by chloride than that of the C-terminal. In the experiment presumably the N-terminal site is apparently kinetically more labile than the C-terminal site.

  8. Xanthohumol, a Prenylated Flavonoid from Hops (Humulus lupulus), Prevents Platelet Activation in Human Platelets

    OpenAIRE

    Ye-Ming Lee; Kuo-Hsien Hsieh; Wan-Jung Lu; Hsiu-Chu Chou; Duen-Suey Chou; Li-Ming Lien; Joen-Rong Sheu; Kuan-Hung Lin

    2012-01-01

    Xanthohumol is the principal prenylated flavonoid in the hop plant (Humulus lupulus L.). Xanthohumol was found to be a very potent cancer chemopreventive agent through regulation of diverse mechanisms. However, no data are available concerning the effects of xanthohumol on platelet activation. The aim of this paper was to examine the antiplatelet effect of xanthohumol in washed human platelets. In the present paper, xanthohumol exhibited more-potent activity in inhibiting platelet aggregation...

  9. Cytotoxic and leishmanicidal properties of garcinielliptone FC, a prenylated benzophenone from Platonia insignis.

    Science.gov (United States)

    Costa Júnior, Joaquim S; de Almeida, Antonia Amanda Cardoso; de Barros Falcão Ferraz, Alexandre; Rossatto, Raíssa Rebés; Silva, Teresinha G; Silva, Paulo B N; Militão, Gardenia C G; das Graças Lopes Citó, Antonia Maria; Santana, Lorena Citó Lopes Resende; de Amorim Carvalho, Fernando Aécio; Freitas, Rivelilson M

    2013-03-01

    Garcinielliptone FC (GFC), a natural prenylated benzophenone, was extracted from Platonia insignis Mart. (Clusiaceae), a native plant commonly known as bacuri and used in traditional Brazilian medicine for the treatment of skin diseases. The aim of this study was to evaluate the cytotoxic and leishmanicidal effects of GFC using in vitro models. The experimental data demonstrated that the polyisoprenylated benzophenone GFC possesses cytotoxic and leishmanicidal activities.

  10. Prenylated flavanones and flavanonols as chemical markers in Glycosmis species (Rutaceae).

    Science.gov (United States)

    Lukaseder, Brigitte; Vajrodaya, Srunya; Hehenberger, Tina; Seger, Christoph; Nagl, Michael; Lutz-Kutschera, Gerda; Robien, Wolfgang; Greger, Harald; Hofer, Otmar

    2009-05-01

    Fifteen prenylated or geranylated flavanones and flavanonols were isolated from the leaf extracts of different Glycosmis species collected in Thailand and Malaysia. All structures were elucidated by spectroscopic methods, especially 1D and 2D NMR. Six compounds were described for the first time and two were only known so far as synthetic products. The chemotaxonomic significance of flavanoid accumulation within the genus Glycosmis is highlighted.

  11. Increased RhoA prenylation in the loechrig (loe mutant leads to progressive neurodegeneration.

    Directory of Open Access Journals (Sweden)

    Mandy Cook

    Full Text Available The Drosophila mutant loechrig (loe shows age-dependent degeneration of the nervous system and is caused by the loss of a neuronal isoform of the AMP-activated protein kinase (AMPK γ-subunit (also known as SNF4Aγ. The trimeric AMPK complex is activated by low energy levels and metabolic insults and regulates multiple important signal pathways that control cell metabolism. A well-known downstream target of AMPK is hydroxyl-methylglutaryl-CoA reductase (HMGR, a key enzyme in isoprenoid synthesis, and we have previously shown that HMGR genetically interacts with loe and affects the severity of the degenerative phenotype. Prenylation of proteins like small G-proteins is an important posttranslational modification providing lipid moieties that allow the association of these proteins with membranes, thereby facilitating their subsequent activation. Rho proteins have been extensively studied in neuronal outgrowth, however, much less is known about their function in neuronal maintenance. Here we show that the loe mutation interferes with isoprenoid synthesis, leading to increased prenylation of the small GTPase Rho1, the fly orthologue of vertebrate RhoA. We also demonstrate that increased prenylation and Rho1 activity causes neurodegeneration and aggravates the behavioral and degenerative phenotypes of loe. Because we cannot detect defects in the development of the central nervous system in loe, this suggests that loe only interferes with the function of the RhoA pathway in maintaining neuronal integrity during adulthood. In addition, our results show that alterations in isoprenoids can result in progressive neurodegeneration, supporting findings in vertebrates that prenylation may play a role in neurodegenerative diseases like Alzheimer's Disease.

  12. Unusual cyclic terpenoids with terminal pendant prenyl moieties: from occurrence to synthesis.

    Science.gov (United States)

    Kulcitki, Veaceslav; Harghel, Petru; Ungur, Nicon

    2014-12-01

    The paper reviews the known examples of cyclic terpenoids produced from open chain polyenic precursors by an "unusual" biosynthetic pathway, involving selective electrophilic attack on an internal double bond followed by cyclization. The resulting compounds possess cyclic backbones with pendant terminal prenyl groups. Synthetic approaches applied for the synthesis of such specifically functionalized compounds are also discussed, as well as biological activity of reported representatives.

  13. Promoting effects of isobavachin on neurogenesis of mouse embryonic stem cells were associated with protein prenylation

    Institute of Scientific and Technical Information of China (English)

    Dan-yin WANG; Yu-zhe HU; Si-si KONG; Yong-ping YU; Dan-yan ZHU; Yi-dia LOU

    2011-01-01

    Aim:Some small molecules can induce mouse embryonic stem(ES)cells to differentiate into neuronal cells.Here.we explored the effect of isobavachin(IBA),a compound with a prenyl group at position 8 of ring A.on promoting neuronal differentiation and the potential role of its protein prenylation.Methods:The hanging drop method was employed for embryonic body(EB)formation to mimic embryo development in vivo.The EBs were treated with IBA at a final concentration of 10-7mol/L from EB stage(d 4)to d 8+10.Geranylgeranyltransferase l inhibitor GGTI298 was subsequently used to disrupt protein prenylation.Neuronal subtypes.including neurons and astrocytes, were observed by fluorescence microscopy.Gene and protein expression levels were detected using RT-PCR and Western blot analysis, respectively.Results:With IBA treatment,nestin was highly expressed in the neural progenitors generated from EBs(d 4,d 8+O).EBs then further differentiated into neurons(marked by 13-tubulin III)and astrocytes(marked by GF_AP), which were both Up-regulated in a timedependent manner on d 8;+5 and d 8+10.Co-treatment with GGTI-298 selectively abolished the IBA-induced neuronal differentiatjon.Moreover,in the MAPK pathway.p38 and JNK phosphorylation were down-regulated,while ERK phosphorylation was up-regulated after IBA treatment at different neuronaI differentiation passages.Conclusion:IBA can facilitate mouse ES cells differentiating into neuronal cells.The mechanism involved protein prenylation and,Subseauently,phos-ERK activation and the phos-p38 off pathway.

  14. Role of Intestinal Hydrolase in the Absorption of Prenylated Flavonoids Present in Yinyanghuo

    Directory of Open Access Journals (Sweden)

    Ming Hu

    2011-02-01

    Full Text Available Purpose: Yinyanghuo (Herba Epimdii is a traditional Chinese herb containing prenylated flavonoids as its active constituents. The aim of this study was to examine the significance of the intestinal hydrolysis of prenylated flavonoids by lactase phlorizin hydrolase (LPH, an enzyme at the brush border membrane of intestinal cells. Methods: A four-site perfused rat intestinal model was used. The concentration of the flavonoids of interest and their metabolites in different intestinal segements were analyzed by HPLC, and the apparent permeabilities were calculated. A lactase phlorizin hydrolase inhibitor (gluconolactone was employed to investigate the mechanism of the intestinal absorption, and the metabolites of the four flavonoids were identified using LC/MS/MS. Results: Diglycosides (icariin or triglycosides (epimedin A, epimedin B, and epimedin C were hydrolyzed rapidly in duodenum and jejunum producing one or two metabolites, while a monoglycoside (baohuoside I was absorbed directly. When co-perfused with glucono-lactone, both the hydrolysis of diglycosides and triglycosides were significantly inhibited, with inhibition rates for icariin (62%, 50%, 40%, 46%, epimedin A, (55%, 26%, 21%, 14%; epimedin B (42%, 40%, 74%, 22%, and epimedin C (42%, 40%, 52%, 35% in duodenum, jejunum, ileum, and colon, respectively. Also the metabolites of icariin, epimedin A, epimedin B, and epimedin C were identified as baohuoside I (one of two, sagittatoside A, sagittatoside B, and 2"-O-rhamnosylicariside II, respectively. Conclusions: The results showed that lactase phlorizin hydrolase was a major determinant of the intestinal absorption of prenylated flavonoids present in Yinyanghuo.

  15. Enhanced triterpene accumulation in Panax ginseng hairy roots overexpressing mevalonate-5-pyrophosphate decarboxylase and farnesyl pyrophosphate synthase.

    Science.gov (United States)

    Kim, Yong-Kyoung; Kim, Yeon Bok; Uddin, Md Romij; Lee, Sanghyun; Kim, Soo-Un; Park, Sang Un

    2014-10-17

    To elucidate the function of mevalonate-5-pyrophosphate decarboxylase (MVD) and farnesyl pyrophosphate synthase (FPS) in triterpene biosynthesis, the genes governing the expression of these enzymes were transformed into Panax ginseng hairy roots. All the transgenic lines showed higher expression levels of PgMVD and PgFPS than that by the wild-type control. Among the hairy root lines transformed with PgMVD, M18 showed the highest level of transcription compared to the control (14.5-fold higher). Transcriptions of F11 and F20 transformed with PgFPS showed 11.1-fold higher level compared with control. In triterpene analysis, M25 of PgMVD produced 4.4-fold higher stigmasterol content (138.95 μg/100 mg, dry weight [DW]) than that by the control; F17 of PgFPS showed the highest total ginsenoside (36.42 mg/g DW) content, which was 2.4-fold higher compared with control. Our results indicate that metabolic engineering in P. ginseng was successfully achieved through Agrobacterium rhizogenes-mediated transformation and that the accumulation of phytosterols and ginsenosides was enhanced by introducing the PgMVD and PgFPS genes into the hairy roots of the plant. Our results suggest that PgMVD and PgFPS play an important role in the triterpene biosynthesis of P. ginseng.

  16. Cardiac amyloidosis detection with pyrophosphate-99mTc scintigraphy

    Energy Technology Data Exchange (ETDEWEB)

    Souza, D.S.F.; Ichiki, W.A.; Coura Filho, G.B.; Izaki, M.; Giorgi, M.C.P.; Soares Junior, J; Meneghetti, J.C. [Universidade de Sao Paulo (FM/USP), SP (Brazil). Fac. de Medicina. Instituto do Coracao. Servico de Medicina Nuclear e Imagem Molecular

    2008-07-01

    Full text: Introduction: Amyloidosis is a rare disease, characterized by extracellular deposition of insoluble amyloid fibrils in organs and tissues. It may affect virtually any system, preferably heart, kidneys and liver. The cardiac involvement produces a spectrum of clinical features, usually with progressive dysfunction. Early diagnosis is important for institution of appropriate therapy. Case report: Male patient, 75 years old, with diagnosed congestive heart failure functional class III and Mobitz II second-degree atrial-ventricular block, was hospitalized for implantation of definitive cardiac pacemaker. Patient mentioned history of worsening effort dyspnoea over a one-month period, progressing to minimum effort, orthopnea, paroxysmal nocturnal dyspnoea and paroxysms of dry cough, and swelling of lower limbs. Echocardiography showed diffuse hypertrophy of left ventricle (LV), with systolic dysfunction due to diffuse hypokinesia and hyperrefringent aspect in the septum. It was questioned a cardiac infiltrating process. Cardiac amyloidosis was considered as a diagnostic hypothesis. The patient underwent a pyrophosphate-{sup 99m}Tc scintigraphy, which showed abnormal tracer uptake in the heart projection, with diffuse pattern on the left ventricle walls, compatible with the clinical suspicion cardiac amyloidosis, which was later confirmed by endomyocardial biopsy. Discussion: In this case report, the patient had clinical and other auxiliary examinations, such as electrocardiography and Doppler echocardiography, compatible with cardiac amyloidosis, which led to implementation with pyrophosphate-{sup 99m}Tc scintigraphy and later endomyocardial biopsy. Cardiac amyloidosis occurs in about half the cases of primary amyloidosis (AL) and is rare in secondary amyloidosis (AA). Its clinical presentation is polymorphic and it can be classified into four distinctive types: restrictive cardiomyopathy, systolic dysfunction, postural hypotension and conduction disorders

  17. Individual Vgamma2-Jgamma1.2+ T cells respond to both isopentenyl pyrophosphate and Daudi cell stimulation: generating tumor effectors with low molecular weight phosphoantigens.

    Science.gov (United States)

    Hebbeler, Andrew M; Cairo, Cristiana; Cummings, Jean Saville; Pauza, C David

    2007-06-01

    Human Vgamma2Vdelta2 T cells exhibit T cell receptor-dependent, MHC-unrestricted recognition of antigen and play important roles in tumor and pathogen immunity. To characterize antigen recognition by the Vgamma2Vdelta2 TCR, we used the combined approach of spectratyping and CDR3 sequence analysis that measures changes in the TCR repertoire before and after stimulation with a phosphoantigen (isopentenyl pyrophosphate) or an irradiated tumor cell line (Daudi B lymphoma). Here we describe common Vgamma2 chains that are substantially involved in the response to both phosphoantigens and tumor cells. The recognition properties of common Vgamma2 chains explains the observation that Vgamma2Vdelta2 T cells expanded by phosphoantigen stimulation specifically recognize and kill some but not all tumor cell lines. Our studies further justify efforts to stimulate tumor immunity by administering low molecular weight phosphoantigens and boosting the frequency and tumor effector functions of circulating Vgamma2Vdelta2 T cells.

  18. Structure-Based Inhibitors Exhibit Differential Activities against Helicobacter pylori and Escherichia coli Undecaprenyl Pyrophosphate Synthases

    Directory of Open Access Journals (Sweden)

    Chih-Jung Kuo

    2008-01-01

    Full Text Available Helicobacter pylori colonizes the human gastric epithelium and causes diseases such as gastritis, peptic ulcers, and stomach cancer. Undecaprenyl pyrophosphate synthase (UPPS, which catalyzes consecutive condensation reactions of farnesyl pyrophosphate with eight isopentenyl pyrophosphate to form lipid carrier for bacterial peptidoglycan biosynthesis, represents a potential target for developing new antibiotics. In this study, we solved the crystal structure of H. pylori UPPS and performed virtual screening of inhibitors from a library of 58,635 compounds. Two hits were found to exhibit differential activities against Helicobacter pylori and Escherichia coli UPPS, giving the possibility of developing antibiotics specially targeting pathogenic H. pylori without killing the intestinal E. coli.

  19. Calcium pyrophosphate powder derived from avian eggshell waste

    Directory of Open Access Journals (Sweden)

    T. H. A. Corrêa

    Full Text Available Abstract Calcium pyrophosphate (CPP was prepared by a simple precipitation method using avian eggshell waste as a low-cost alternative calcium precursor source. The synthesized CPP powder was characterized by X-ray diffraction (XRD, scanning electron microscopy (SEM/EDS, thermogravimetric analysis (TGA, and Fourier transform infrared spectroscopy (FTIR. The results indicate that pure β-CPP nanocrystallites (Ca/P = 1.067 were successfully synthesized from avian eggshell waste. The correlation among XRD, SEM/EDS, TGA, and FTIR data is well established. The β-CPP particle exhibited spherical morphology with average crystallite size of 62.3 nm, and can be an important bioceramic for medical applications.

  20. Enlarging the scope of cell penetrating prenylated peptides to include farnesylated “CAAX” box sequences and diverse cell types

    Science.gov (United States)

    Ochocki, Joshua D.; Igbavboa, Urule; Wood, W. Gibson; Wattenberg, Elizabeth V.; Distefano, Mark D.

    2010-01-01

    Protein prenylation is a post-translational modification that is present in a large number of proteins; it has been proposed to be responsible for membrane association and protein-protein interactions which contribute to its role in signal transduction pathways. Research has been aimed at inhibiting prenylation with farnesyltransferase inhibitors (FTIs) based on the finding that the farnesylated protein Ras is implicated in 30% of human cancers. Despite numerous studies on the enzymology of prenylation in vitro, many questions remain about the process of prenylation as it occurs in living cells. Here we describe the preparation of a series of farnesylated peptides that contain sequences recognized by protein farnesyltransferase. Using a combination of flow cytometry and confocal microscopy, we show that these peptides enter a variety of different cell types. A related peptide where the farnesyl group has been replaced by a disulfide-linked decyl group is also shown to be able to efficiently enter cells. These results highlight the applicability of these peptides as a platform for further study of protein prenylation and subsequent processing in live cells. PMID:20584014

  1. Mitochondrial uptake of thiamin pyrophosphate: physiological and cell biological aspects.

    Directory of Open Access Journals (Sweden)

    Veedamali S Subramanian

    Full Text Available Mammalian cells obtain vitamin B1 (thiamin from their surrounding environment and convert it to thiamin pyrophosphate (TPP in the cytoplasm. Most of TPP is then transported into the mitochondria via a carrier-mediated process that involves the mitochondrial thiamin pyrophosphate transporter (MTPPT. Knowledge about the physiological parameters of the MTPP-mediated uptake process, MTPPT targeting and the impact of clinical mutations in MTPPT in patients with Amish lethal microcephaly and neuropathy and bilateral striatal necrosis are not fully elucidated, and thus, were addressed in this study using custom-made (3H-TPP as a substrate and mitochondria isolated from mouse liver and human-derived liver HepG2 cells. Results showed (3H-TPP uptake by mouse liver mitochondria to be pH-independent, saturable (Km = 6.79±0.53 µM, and specific for TPP. MTPPT protein was expressed in mouse liver and HepG2 cells, and confocal images showed a human (hMTPPT-GFP construct to be targeted to mitochondria of HepG2 cells. A serial truncation analysis revealed that all three modules of hMTPPT protein cooperated (although at different levels of efficiency in mitochondrial targeting rather than acting autonomously as independent targeting module. Finally, the hMTPPT clinical mutants (G125S and G177A showed proper mitochondrial targeting but displayed significant inhibition in (3H-TPP uptake and a decrease in level of expression of the MTPPT protein. These findings advance our knowledge of the physiology and cell biology of the mitochondrial TPP uptake process. The results also show that clinical mutations in the hMTPPT system impair its functionality via affecting its level of expression with no effect on its targeting to mitochondria.

  2. A rapid screening method for prenylated flavonoids with ultra-high-performance liquid chromatography/electrospray ionisation mass spectrometry in licorice root extracts

    NARCIS (Netherlands)

    Simons, R.; Vincken, J.P.; Bakx, E.J.; Verbruggen, M.A.; Gruppen, H.

    2009-01-01

    Due to their substitution with an isoprenoid group, prenylated flavonoids have an increased affinity for biological membranes and target proteins, enhancing their potential bioactivity. Although many prenylated flavonoids have been described, there are no methods that specifically screen for their p

  3. Differential Effects of Prenylation and S-Acylation on Type I and II ROPS Membrane Interaction and Function1[W][OA

    Science.gov (United States)

    Sorek, Nadav; Gutman, Orit; Bar, Einat; Abu-Abied, Mohamad; Feng, Xuehui; Running, Mark P.; Lewinsohn, Efraim; Ori, Naomi; Sadot, Einat; Henis, Yoav I.; Yalovsky, Shaul

    2011-01-01

    Prenylation primarily by geranylgeranylation is required for membrane attachment and function of type I Rho of Plants (ROPs) and Gγ proteins, while type II ROPs are attached to the plasma membrane by S-acylation. Yet, it is not known how prenylation affects ROP membrane interaction dynamics and what are the functional redundancy and specificity of type I and type II ROPs. Here, we have used the expression of ROPs in mammalian cells together with geranylgeranylation and CaaX prenylation-deficient mutants to answer these questions. Our results show that the mechanism of type II ROP S-acylation and membrane attachment is unique to plants and likely responsible for the viability of plants in the absence of CaaX prenylation activity. The prenylation of ROPs determines their steady-state distribution between the plasma membrane and the cytosol but has little effect on membrane interaction dynamics. In addition, the prenyl group type has only minor effects on ROP function. Phenotypic analysis of the CaaX prenylation-deficient pluripetala mutant epidermal cells revealed that type I ROPs affect cell structure primarily on the adaxial side, while type II ROPs are functional and induce a novel cell division phenotype in this genetic background. Taken together, our studies show how prenyl and S-acyl lipid modifications affect ROP subcellular distribution, membrane interaction dynamics, and function. PMID:21139084

  4. Preparation of tricalcium phosphate/calcium pyrophosphate structures via rapid prototyping.

    Science.gov (United States)

    Gbureck, Uwe; Hölzel, Tanja; Biermann, Isabell; Barralet, Jake E; Grover, Liam M

    2008-04-01

    Custom made tricalcium phosphate/calcium pyrophosphate bone substitutes with a well-defined architecture were fabricated in this study using 3D powder printing with tricalcium phosphate (TCP) powder and a liquid phase of phosphoric acid. The primary formed matrix of dicalcium phosphate dihydrate (DCPD, brushite) was converted in a second step to calcium pyrophosphate (CPP) by heat treatment in the temperature range 1,100-1,300 degrees C. The structures exhibited compressive strengths between 0.8 MPa and 4 MPa after sintering at 1,100-1,250 degrees C, higher strengths were obtained by increasing the amount of pyrophosphate formed in the matrix due to a post-hardening regime prior sintering as well as by the formation of a glass phase from TCP and calcium pyrophosphate above 1,280 degrees C, which resulted in a strong densification of the samples and compressive strength of >40 MPa.

  5. The effect of preparation method on the proton conductivity of indium doped tin pyrophosphates

    DEFF Research Database (Denmark)

    Anfimova, Tatiana; Lie-Andersen, T.; Jensen, E. Pristed

    2015-01-01

    Indium doped tin pyrophosphates were prepared by three synthetic routes. A heterogeneous synthesis from metal oxides with excess phosphoric acid produces crystalline phosphate particles with a phosphorus rich amorphous phase along the grain boundaries. The amorphous phase prevents the agglomerati...

  6. Inositol pyrophosphates modulate cell cycle independently of alteration in telomere length.

    Science.gov (United States)

    Banfic, Hrvoje; Crljen, Vladiana; Lukinovic-Skudar, Vesna; Dembitz, Vilma; Lalic, Hrvoje; Bedalov, Antonio; Visnjic, Dora

    2016-01-01

    Synthesis of inositol pyrophosphates through activation of Kcs1 plays an important role in the signalling response required for cell cycle progression after mating pheromone arrest. Overexpression of Kcs1 doubled the level of inositol pyrophosphates when compared to wild type cells and 30 min following the release from α-factor block further increase in inositol pyrophosphates was observed, which resulted that cells overexpressing Kcs1 reached G2/M phase earlier than wild type cells. Similar effect was observed in ipk1Δ cells, which are unable to synthesize IP6-derived inositol pyrophosphates (IP7 and IP8) but will synthesize IP5-derived inositol pyrophosphates (PP-IP4 and (PP)2-IP3). Although ipk1Δ cells have shorter telomeres than wild type cells, overexpression of Kcs1 in both strains have similar effect on cell cycle progression. As it is known that PP-IP4 regulates telomere length through Tel1, inositol polyphosphates, cell cycle and telomere length were determined in tel1Δ cells. The release of the cells from α-factor block and overexpression of Kcs1 in tel1Δ cells produced similar effects on inositol pyrophosphates level and cell cycle progression when compared to wild type cells, although tel1Δ cells possesses shorter telomeres than wild type cells. It can be concluded that telomere length does not affect cell cycle progression, since cells with short telomeres (ipk1Δ and tel1Δ) progress through cell cycle in a similar manner as wild type cells and that overexpression of Kcs1 in cells with either short or normal telomeres will increase S phase progression without affecting telomere length. Furthermore, IP5-derived inositol pyrophosphates can compensate for the loss of IP6-derived inositol pyrophosphates, in modulating S phase progression of the cell cycle.

  7. Simple tools for assembling and searching high-density picolitre pyrophosphate sequence data

    OpenAIRE

    Parker Andrew G; Parker Nicolas J

    2008-01-01

    Abstract Background The advent of pyrophosphate sequencing makes large volumes of sequencing data available at a lower cost than previously possible. However, the short read lengths are difficult to assemble and the large dataset is difficult to handle. During the sequencing of a virus from the tsetse fly, Glossina pallidipes, we found the need for tools to search quickly a set of reads for near exact text matches. Methods A set of tools is provided to search a large data set of pyrophosphate...

  8. Evaluation of anti-inflammatory activity of prenylated substances isolated from Morus alba and Morus nigra.

    Science.gov (United States)

    Zelová, Hana; Hanáková, Zuzana; Čermáková, Zuzana; Šmejkal, Karel; Dalĺ Acqua, Stefano; Babula, Petr; Cvačka, Josef; Hošek, Jan

    2014-06-27

    Chromatographic separation of root extracts of Morus alba and M. nigra led to the identification of the 2-arylbenzofurans moracin C (1), mulberrofuran Y (2), and mulberrofuran H (3), and the prenylated flavonoids kuwanon E (4), kuwanon C (5), sanggenon H (6), cudraflavone B (7), and morusinol (8), and the Diels-Alder adducts soroceal (9), and sanggenon E (10). The cytotoxicity and their antiphlogistic activity, determined as the attenuation of the secretion of TNF-α and IL-1β and the inhibition of NF-κB nuclear translocation in LPS-stimulated macrophages, were evaluated for compounds 1-10.

  9. Prenylated Coumarins from Heracleum stenopterum, Peucedanum praeruptorum, Clausena lansium, and Murraya paniculata

    Directory of Open Access Journals (Sweden)

    Xiang-Mei Li

    2016-09-01

    Full Text Available Abstract Four hitherto unknown prenylated coumarins, namely 6″-O-β-d-apiofuranosylapterin (1, 4′-O-isobutyroylpeguangxienin (2, 6-(3-methyl-2-oxobutyroyl-7-methoxycoumarin (3, and 6-hydroxycoumurrayin (4, were isolated from the ethanol extract of Heracleum stenopterum, Peucedanum praeruptorum, Clausena lansium, and Murraya paniculata, respectively. Their chemical structures were established on the basis of extensive spectroscopic analysis. Compound 2 exhibited in vitro cytotoxic activity against five human cancer cell lines (HL-60, A-549, SMMC-7721, MCF-7, and SW-480 with IC50 values ranging from 15.9 to 23.2 μM. Graphical Abstract

  10. Two New Prenylated Stilbenes with an Irregular Sesquiterpenyl Side Chain from Propolis from Fiji Islands

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    Boryana Trusheva

    2016-01-01

    Full Text Available Two new prenylated stilbenes with an irregular sesquiterpenyl side chain, solomonin B (1 and solomonin C (2, together with four known compounds, glyasperin A (3, isolated for the first time from propolis, kumatakenin (4, macarangin (5 and mangiferolic acid (6 were isolated from ethanol extract of propolis from Fiji islands. The compounds structures were determined based on their spectral data analysis (1D- and 2D NMR, UV and HREIMS and comparison with literature data. The chemical composition of propolis from Fiji islands was determined for the first time.

  11. Biotransformation of Resveratrol: New Prenylated trans-Resveratrol Synthesized by Aspergillus sp. SCSIOW2

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    Liyan Wang

    2016-07-01

    Full Text Available Arahypin-16 (1, a new prenylated resveratrol with a unique dihydrobenzofuran ring, has been isolated as a microbial metabolite of resveratrol (2 from whole-cell fermentation of Aspergillus sp. SCSIOW2. The stereochemistry of 1 was determined by ECD calculations. 1 showed about half of the extracellular radical scavenging effect (IC50 = 161.4 μM compared with resveratrol (IC50 = 80.5 μM, while on biomembranes it exhibited the same range of protection effects against free radicals generated from AAPH (IC50 = 78.6 μM and 87.9 μM.

  12. Use of synthetic isoprenoids to target protein prenylation and Rho GTPases in breast cancer invasion.

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    Min Chen

    Full Text Available Dysregulation of Ras and Rho family small GTPases drives the invasion and metastasis of multiple cancers. For their biological functions, these GTPases require proper subcellular localization to cellular membranes, which is regulated by a series of post-translational modifications that result in either farnesylation or geranylgeranylation of the C-terminal CAAX motif. This concept provided the rationale for targeting farnesyltransferase (FTase and geranylgeranyltransferases (GGTase for cancer treatment. However, the resulting prenyl transferase inhibitors have not performed well in the clinic due to issues with alternative prenylation and toxicity. As an alternative, we have developed a unique class of potential anti-cancer therapeutics called Prenyl Function Inhibitors (PFIs, which are farnesol or geranyl-geraniol analogs that act as alternate substrates for FTase or GGTase. Here, we test the ability of our lead PFIs, anilinogeraniol (AGOH and anilinofarnesol (AFOH, to block the invasion of breast cancer cells. We found that AGOH treatment effectively decreased invasion of MDA-MB-231 cells in a two-dimensional (2D invasion assay at 100 µM while it blocked invasive growth in three-dimensional (3D culture model at as little as 20 µM. Notably, the effect of AGOH on 3D invasive growth was phenocopied by electroporation of cells with C3 exotransferase. To determine if RhoA and RhoC were direct targets of AGOH, we performed Rho activity assays in MDA-MB-231 and MDA-MB-468 cells and found that AGOH blocked RhoA and RhoC activation in response to LPA and EGF stimulation. Notably, the geranylgeraniol analog AFOH was more potent than AGOH in inhibiting RhoA and RhoC activation and invasive growth. Interestingly, neither AGOH nor AFOH impacted 3D growth of MCF10A cells. Collectively, this study demonstrates that AGOH and AFOH dramatically inhibit breast cancer invasion, at least in part by blocking Rho function, thus, suggesting that targeting

  13. Amyrisins A-C, O-prenylated flavonoids from Amyris madrensis.

    Science.gov (United States)

    Peng, Jiangnan; Hartley, Rachel M; Fest, Gary A; Mooberry, Susan L

    2012-03-23

    Three new O-prenylated flavonoids, amyrisins A-C (1-3), were isolated from the leaves and twigs of Amyris madrensis, along with the known compound polygamain (4). The structures of 1-3 were elucidated on the basis of the analysis of spectroscopic data interpretation. Amyrisins B (2) and C (3) showed moderate cytotoxicity against PC-3 and DU 145 prostate cancer cells with IC(50) values of 17.5 and 23 μM, respectively, while amyrisin A (1) did not show any cytotoxicity at the highest concentration tested, 50 μM. Polygamain (4) exhibited potent antiproliferative and microtubule-depolymerizing activities.

  14. Prenylated Coumarins from Heracleum stenopterum, Peucedanum praeruptorum, Clausena lansium, and Murraya paniculata.

    Science.gov (United States)

    Li, Xiang-Mei; Jiang, Xian-Jun; Yang, Ku; Wang, Li-Xia; Wen, Shi-Zhen; Wang, Fei

    2016-10-01

    Four hitherto unknown prenylated coumarins, namely 6″-O-β-D-apiofuranosylapterin (1), 4'-O-isobutyroylpeguangxienin (2), 6-(3-methyl-2-oxobutyroyl)-7-methoxycoumarin (3), and 6-hydroxycoumurrayin (4), were isolated from the ethanol extract of Heracleum stenopterum, Peucedanum praeruptorum, Clausena lansium, and Murraya paniculata, respectively. Their chemical structures were established on the basis of extensive spectroscopic analysis. Compound 2 exhibited in vitro cytotoxic activity against five human cancer cell lines (HL-60, A-549, SMMC-7721, MCF-7, and SW-480) with IC50 values ranging from 15.9 to 23.2 μM.

  15. Alteration of RhoA Prenylation Ameliorates Cardiac and Vascular Remodeling in Spontaneously Hypertensive Rats

    Directory of Open Access Journals (Sweden)

    Jian Yang

    2016-06-01

    Full Text Available Background: In our previous study, farnesyl pyrophosphate synthase (FPPS was shown to be increased in spontaneously hypertensive rats (SHR and in mice with angiotensin-II induced cardiac hypertrophy. Overexpression of FPPS induced cardiac hypertrophy and fibrosis in mice, accompanied by an increase in the synthesis of farnesyl pyrophosphate (FPP and geranylgeranyl pyrophosphate (GGPP. In the present study, we investigated the mechanisms of reversing cardiovascular remodeling in SHR by inhibiting FPPS. Methods and Results: Six-week-old rats were given vehicle or an FPPS inhibitor (alendronate, 100 ug/kg/d daily for twelve weeks by osmotic mini-pump. The results demonstrated that FPPS inhibition attenuated cardiac hypertrophy and fibrosis in SHR as shown by the heart weight to body weight ratio, echocardiographic parameters, and histological examination. In addition, FPPS inhibition attenuated aortic remodeling as shown by reduced media thickness, media cross-sectional area and collagen of the aorta as well as SBP, DBP, MBP. Furthermore, 12 weeks of alendronate treatment significantly decreased FPP and GGPP levels, RhoA activation and geranylgeranylation in the heart and aorta, all of which were significantly upregulated in SHR compared with normotensive Wistar-Kyoto rats. Conclusion: Taken together, these results indicate that chronic treatment with alendronate decreases the development of cardiac and aortic remodeling, by a pathway which involves inhibition of the geranylgeranylation and activation of RhoA.

  16. Biosynthesis of monoterpenes: Stereochemistry of the coupled isomerization and cyclization of geranyl pyrophosphate to camphane and isocamphane monoterpenes

    Energy Technology Data Exchange (ETDEWEB)

    Croteau, R.; Gershenzon, J.; Wheeler, C.J.; Satterwhite, D.M. (Washington State Univ., Pullman (USA))

    1990-03-01

    The conversion of geranyl pyrophosphate to (+)-bornyl pyrophosphate and (+)-camphene is considered to proceed by the initial isomerization of the substrate to (-)-(3R)-linalyl pyrophosphate and the subsequent cyclization of this bound intermediate. In the case of (-)-bornyl pyrophosphate and (-)-camphene, isomerization of the substrate to the (+)-(3S)-linalyl intermediate precedes cyclization. The geranyl and linalyl precursors were shown to be mutually competitive substrates (inhibitors) of the relevant cyclization enzymes isolated from Salvia officinalis (sage) and Tanacetum vulgare (tansy) by the mixed substrate analysis method, demonstrating that isomerization and cyclization take place at the same active site. Incubation of partially purified enzyme preparations with (3R)-(1Z-3H)linalyl pyrophosphate plus (1-14C)geranyl pyrophosphate gave rise to double-labeled (+)-bornyl pyrophosphate and (+)-camphene, whereas incubation of enzyme preparations catalyzing the antipodal cyclizations with (3S)-(1Z-3H)-linalyl pyrophosphate plus (1-14C)geranyl pyrophosphate yielded double-labeled (-)-bornyl pyrophosphate and (-)-camphene. Each product was then transformed to the corresponding (+)- or (-)-camphor without change in the 3H:14C isotope ratio, and the location of the tritium label was deduced in each case by stereoselective, base-catalyzed exchange of the exo-alpha-hydrogen of the derived ketone. The finding that the 1Z-3H of the linalyl precursor was positioned at the endo-alpha-hydrogen of the corresponding camphor in all cases, coupled to the previously demonstrated retention of configuration at C1 of the geranyl substrate in these transformations, confirmed the syn-isomerization of geranyl pyrophosphate to linalyl pyrophosphate and the cyclization of the latter via the anti,endo- conformer.

  17. Evaluation of alkyne-modified isoprenoids as chemical reporters of protein prenylation.

    Science.gov (United States)

    DeGraw, Amanda J; Palsuledesai, Charuta; Ochocki, Joshua D; Dozier, Jonathan K; Lenevich, Stepan; Rashidian, Mohammad; Distefano, Mark D

    2010-12-01

    Protein prenyltransferases catalyze the attachment of C15 (farnesyl) and C20 (geranylgeranyl) groups to proteins at specific sequences localized at or near the C-termini of specific proteins. Determination of the specific protein prenyltransferase substrates affected by the inhibition of these enzymes is critical for enhancing knowledge of the mechanism of such potential drugs. Here, we investigate the utility of alkyne-containing isoprenoid analogs for chemical proteomics experiments by showing that these compounds readily penetrate mammalian cells in culture and become incorporated into proteins that are normally prenylated. Derivatization via Cu(I) catalyzed click reaction with a fluorescent azide reagent allows the proteins to be visualized and their relative levels to be analyzed. Simultaneous treatment of cells with these probes and inhibitors of prenylation reveals decreases in the levels of some but not all of the labeled proteins. Two-dimensional electrophoretic separation of these labeled proteins followed by mass spectrometric analysis allowed several labeled proteins to be unambiguously identified. Docking experiments and density functional theory calculations suggest that the substrate specificity of protein farnesyl transferase may vary depending on whether azide- or alkyne-based isoprenoid analogs is employed. These results demonstrate the utility of alkyne-containing analogs for chemical proteomic applications.

  18. Discovery of prenylated flavonoids with dual activity against influenza virus and Streptococcus pneumoniae.

    Science.gov (United States)

    Grienke, Ulrike; Richter, Martina; Walther, Elisabeth; Hoffmann, Anja; Kirchmair, Johannes; Makarov, Vadim; Nietzsche, Sandor; Schmidtke, Michaela; Rollinger, Judith M

    2016-06-03

    Influenza virus neuraminidase (NA) is the primary target for influenza therapeutics. Severe complications are often related to secondary pneumonia caused by Streptococcus pneumoniae (pneumococci), which also express NAs. Recently, a NA-mediated lethal synergism between influenza A viruses and pneumococci was described. Therefore, dual inhibitors of both viral and bacterial NAs are expected to be advantageous for the treatment of influenza. We investigated the traditional Chinese herbal drug sāng bái pí (mulberry root bark) as source for anti-infectives. Two prenylated flavonoid derivatives, sanggenon G (4) and sanggenol A (5) inhibited influenza A viral and pneumococcal NAs and, in contrast to the approved NA inhibitor oseltamivir, also planktonic growth and biofilm formation of pneumococci. Evaluation of 27 congeners of 5 revealed a correlation between the degree of prenylation and bioactivity. Abyssinone-V 4'-methyl ether (27) inhibited pneumococcal NA with IC50 = 2.18 μM, pneumococcal growth with MIC = 5.63 μM, and biofilm formation with MBIC = 4.21 μM, without harming lung epithelial cells. Compounds 5 and 27 also disrupt the synergism between influenza A virus and pneumococcal NA in vitro, hence functioning as dual-acting anti-infectives. The results warrant further studies on whether the observed disruption of this synergism is transferable to in vivo systems.

  19. Biosynthesis and possible functions of inositol pyrophosphates in plants

    Directory of Open Access Journals (Sweden)

    Sarah Phoebe Williams

    2015-02-01

    Full Text Available Inositol phosphates (InsPs are intricately tied to lipid signaling, as at least one portion of the inositol phosphate signaling pool is derived from hydrolysis of the lipid precursor, phosphatidyl inositol (4,5 bisphosphate. The focus of this review is on the inositol pyrophosphates, which are a novel group of InsP signaling molecules containing diphosphate or triphosphate chains (i.e. PPx attached to the inositol ring. These PPx-InsPs are emerging as critical players in the integration of cellular metabolism and stress signaling in non-plant eukaryotes. Most eukaryotes synthesize the precursor molecule, myo-inositol (1,2,3,4,5,6-hexakisphosphate (InsP6, which can serve as a signaling molecule or as storage compound of inositol, phosphorus, and minerals (referred to as phytic acid. Even though plants produce huge amounts of precursor InsP6 in seeds, almost no attention has been paid to whether PPx-InsPs exist in plants, and if so, what roles these molecules play. Recent work has delineated that Arabidopsis has two genes capable of PP-InsP5 synthesis, and PPx-InsPs have been detected across the plant kingdom. This review will detail the known roles of PPx-InsPs in yeast and animal systems, and provide a description of recent data on the synthesis and accumulation of these novel molecules in plants, and potential roles in signaling.

  20. Solid-phase synthesis of C-terminal peptide libraries for studying the specificity of enzymatic protein prenylation.

    Science.gov (United States)

    Wang, Yen-Chih; Distefano, Mark D

    2012-08-25

    Prenylation is an essential post-translational modification in all eukaryotes. Here we describe the synthesis of a 340-member library of peptides containing free C-termini on cellulose membranes. The resulting library was then used to probe the specificity of protein farnesyltransferase from S. cerevisiae.

  1. Prenylation and Backbone Structure of Flavonoids and Isoflavonoids from Licorice and Hop Influence Their Phase i and II Metabolism

    NARCIS (Netherlands)

    De Schans, Van Milou G.M.; Bovee, Toine F.H.; Stoopen, Geert M.; Lorist, Marlies; Gruppen, Harry; Vincken, Jean Paul

    2015-01-01

    In vitro liver metabolism of 11 prenylated flavonoids and isoflavonoids was investigated by determining their phase I glucuronyl and sulfate metabolites using pork liver preparations. One hundred metabolites were annotated using RP-UHPLC-ESI-MSn. A mass spectrometry-based data interpre

  2. Regiospecificities and Prenylation Mode Specificities of the Fungal Indole Diterpene Prenyltransferases AtmD and PaxD

    Science.gov (United States)

    Liu, Chengwei; Minami, Atsushi; Noike, Motoyoshi; Toshima, Hiroaki; Oikawa, Hideaki

    2013-01-01

    We recently reported the function of paxD, which is involved in the paxilline (compound 1) biosynthetic gene cluster in Penicillium paxilli. Recombinant PaxD catalyzed a stepwise regular-type diprenylation at the 21 and 22 positions of compound 1 with dimethylallyl diphosphate (DMAPP) as the prenyl donor. In this study, atmD, which is located in the aflatrem (compound 2) biosynthetic gene cluster in Aspergillus flavus and encodes an enzyme with 32% amino acid identity to PaxD, was characterized using recombinant enzyme. When compound 1 and DMAPP were used as substrates, two major products and a trace of minor product were formed. The structures of the two major products were determined to be reversely monoprenylated compound 1 at either the 20 or 21 position. Because compound 2 and β-aflatrem (compound 3), both of which are compound 1-related compounds produced by A. flavus, have the same prenyl moiety at the 20 and 21 position, respectively, AtmD should catalyze the prenylation in compound 2 and 3 biosynthesis. More importantly and surprisingly, AtmD accepted paspaline (compound 4), which is an intermediate of compound 1 biosynthesis that has a structure similar to that of compound 1, and catalyzed a regular monoprenylation of compound 4 at either the 21 or 22 position, though the reverse prenylation was observed with compound 1. This suggests that fungal indole diterpene prenyltransferases have the potential to alter their position and regular/reverse specificities for prenylation and could be applicable for the synthesis of industrially useful compounds. PMID:24038699

  3. The Role of Thiamine Pyrophosphate in Prevention of Cisplatin Ototoxicity in an Animal Model

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    Ozan Kuduban

    2013-01-01

    Full Text Available Objective. The aim of this study was to evaluate the effectiveness of thiamine pyrophosphate against cisplatin-induced ototoxicity in guinea pigs. Materials and Methods. Healthy guinea pigs (n=18 were randomly divided into three groups. Group 1 (n=6 received an intraperitoneal injection of saline solution and cisplatin for 7 days, group 2 (n=6 received an intraperitoneal injection of thiamine pyrophosphate and cisplatin for 7 days, and group 3 (n=6 received only intraperitoneal injection of saline for 7 days. The animals in all groups were sacrificed under anesthesia, and their cochleas were harvested for morphological and biochemical observations. Results. In group 1, receiving only cisplatin, cochlear glutathione concentrations, superoxide dismutase, and glutathione peroxidase activities significantly decreased (P<0.05 and malondialdehyde concentrations significantly increased (P<0.05 compared to the control group. In group 2, receiving thiamine pyrophosphate and cisplatin, the concentrations of enzymes were near those of the control group. Microscopic examination showed that outer hair cells, spiral ganglion cells, and stria vascularis were preserved in group 2. Conclusion. Systemic administration of thiamine pyrophosphate yielded statistically significant protection to the cochlea of guinea pigs from cisplatin toxicity. Further experimental animal studies are essential to determine the appropriate indications of thiamine pyrophosphate before clinical use.

  4. Combined effect of strontium and pyrophosphate on the properties of brushite cements.

    Science.gov (United States)

    Alkhraisat, M Hamdan; Mariño, F Tamimi; Rodríguez, C Rueda; Jerez, L Blanco; Cabarcos, E López

    2008-05-01

    In this study we report the synthesis of strontium-containing brushite cement with good cohesion and a diametral tensile strength (DTS) of 5 MPa. The cement powder, composed of beta-tricalcium phosphate (beta-TCP) and monocalcium phosphate, was adjusted by different concentrations of strontium and pyrophosphate ions. The cement liquid phase was 2M phosphoric acid solution. The cement cohesion and mechanical properties were measured after being aged in water for 24h at 37 degrees C. It was found that at low concentration both strontium and pyrophosphate ions inhibit the cement setting reaction. However, the final setting time was significantly reduced when SrCl2 increased from 5 to 10 wt.% at pyrophosphate concentrations equal to or higher than 2.16 wt.%. The incorporation of strontium ions did not increase the DTS of brushite cements significantly. In contrast, the addition of pyrophosphate ions did increase the DTS of brushite cements significantly. When both ions were added simultaneously, the brushite cement with a Sr2+ content of 5 wt.% had the highest DTS value. Nevertheless, the DTS values of Sr-containing cements were significantly reduced if the pyrophosphate concentration was higher than 2.16 wt.%. The Sr2+ ions had a negative effect on brushite cement cohesion, although the solid weight loss started to decrease at Sr2+ concentrations higher than 5 wt.%.

  5. Farnesyl pyrophosphate synthase is the molecular target of nitrogen-containing bisphosphonates.

    Science.gov (United States)

    van Beek, E; Pieterman, E; Cohen, L; Löwik, C; Papapoulos, S

    1999-10-14

    Bisphosphonates (Bps), inhibitors of osteoclastic bone resorption, are used in the treatment of skeletal disorders. Recent evidence indicated that farnesyl pyrophosphate (FPP) synthase and/or isopentenyl pyrophosphate (IPP) isomerase is the intracellular target(s) of bisphosphonate action. To examine which enzyme is specifically affected, we determined the effect of different Bps on incorporation of [(14)C]mevalonate (MVA), [(14)C]IPP, and [(14)C]dimethylallyl pyrophosphate (DMAPP) into polyisoprenyl pyrophosphates in a homogenate of bovine brain. HPLC analysis revealed that the three intermediates were incorporated into FPP and geranylgeranyl pyrophosphate (GGPP). In contrast to clodronate, the nitrogen-containing Bps (NBps), alendronate, risedronate, olpadronate, and ibandronate, completely blocked FPP and GGPP formation and induced in incubations with [(14)C]MVA a 3- to 5-fold increase in incorporation of label into IPP and/or DMAPP. Using a method that could distinguish DMAPP from IPP on basis of their difference in stability in acid, we found that none of the NBps affected the conversion of [(14)C]IPP into DMAPP, catalyzed by IPP isomerase, excluding this enzyme as target of NBp action. On the basis of these and our previous findings, we conclude that none of the enzymes up- or downstream of FPP synthase are affected by NBps, and FPP synthase is, therefore, the exclusive molecular target of NBp action.

  6. Thermoluminescence of cerium and terbium -doped calcium pyrophosphate

    Energy Technology Data Exchange (ETDEWEB)

    Roman L, J.; Cruz Z, E. [UNAM, Instituto de Ciencias Nucleares, Circuito Exterior, Ciudad Universitaria, 04510 Mexico D. F. (Mexico); Lozano R, I. B.; Diaz G, J. A. I., E-mail: jesus.roman@nucleares.unam.mx [IPN, Centro de Investigacion en Ciencia Aplicada y Tecnologia Avanzada, Av. Legaria No. 694, 11500 Mexico D. F. (Mexico)

    2015-10-15

    The aim of this work is to report the thermoluminescence (Tl) response of Calcium Pyrophosphate phosphor doped with Cerium and Terbium impurities (Ca{sub 2}P{sub 2}O{sub 7}:Ce{sup 3+},Tb{sup 3+}). The phosphors were synthesized using the co-precipitation method and annealed at 900 degrees C by two hours for obtain the β phase. The intentional doping with Ce and Tb ions was 1 at.% and 0.1 at.%, whereas in the EDS results the concentration of impurities was 0.39 at.% and 0.05 at.%, respectively. The superficial morphology of phosphor is mainly composed by thin wafers of different size. All samples were exposed to gamma rays from {sup 60}Co in the Gammacell-200 irradiator. The Tl response of the phosphor was measured from Rt up to 350 degrees C and under nitrogen atmosphere in a Harshaw TLD 3500 reader. The glow curves of the Ca{sub 2}P{sub 2}O{sub 7}:Ce{sup 3+},Tb{sup 3+} powders showed a broad intense Tl peak centered at 165 degrees C and a shoulder at approximate 260 degrees C was observed. A linear Tl response in the range of absorbed dose of 0.2 to 10 Gy was obtained. Tl glow curves were analyzed using the initial rise (IR)and computerized glow curve deconvolution methods to evaluate the kinetics parameters such as activation energy (E), frequency factor (s) and kinetic order (b). (Author)

  7. Joint scintigraphy using technetium-99m pyrophosphate in experimental hemarthrosis

    Energy Technology Data Exchange (ETDEWEB)

    Salimi, Z.; Vas, W.; Restrepo, G.

    1986-02-01

    To determine the validity of a method for induction of experimental hemarthrosis in dogs and for the nuclear imaging of hemarthrosis, serial technetium-99m pyrophosphate ((/sup 99m/Tc)PYP) flow and blood-pool scans were performed monthly in eight dogs who received bi-weekly injections of autologous blood into their femoro-tibial joints (also called stifle joint). In four control dogs, one joint was injected with saline while the other joint received only a sham injection. In addition, two dogs received intra-articular injections of autologous blood into their right stifle joint and saline into their left stifle joint. These dogs were studied with /sup 99m/TcO/sub 4/ joint scintigraphy at monthly intervals. The dogs were periodically taken out of the study and explored surgically. Pathologic examination of synovial tissue was performed. Serial radiographs were also obtained and correlated with the scan and surgical findings. There was a striking abnormal increase in blood-pool activity of (/sup 99m/Tc)PYP in the treated stifle joints, commencing at the first examination after 1 mo of blood injections and continuing for the length of the study. All radiographs showed only minimal joint space widening and some soft-tissue swelling. On pathologic examination, both grossly and microscopically, there was profuse pannus formation, with intense inflammatory infiltrate replacing much of the subsynovial fat. The scintigraphic findings correlated well with these pathologic findings. This study not only validates this method for simulating hemophilic hemarthrosis but also suggests that (/sup 99m/Tc)PYP joint scintigraphy is a simple, and noninvasive method for monitoring the early changes in hemophilic arthropathy and is superior to pertechnetate imaging for this disease process.

  8. Central role of pyrophosphate in acellular cementum formation.

    Directory of Open Access Journals (Sweden)

    Brian L Foster

    Full Text Available BACKGROUND: Inorganic pyrophosphate (PP(i is a physiologic inhibitor of hydroxyapatite mineral precipitation involved in regulating mineralized tissue development and pathologic calcification. Local levels of PP(i are controlled by antagonistic functions of factors that decrease PP(i and promote mineralization (tissue-nonspecific alkaline phosphatase, Alpl/TNAP, and those that increase local PP(i and restrict mineralization (progressive ankylosis protein, ANK; ectonucleotide pyrophosphatase phosphodiesterase-1, NPP1. The cementum enveloping the tooth root is essential for tooth function by providing attachment to the surrounding bone via the nonmineralized periodontal ligament. At present, the developmental regulation of cementum remains poorly understood, hampering efforts for regeneration. To elucidate the role of PP(i in cementum formation, we analyzed root development in knock-out ((-/- mice featuring PP(i dysregulation. RESULTS: Excess PP(i in the Alpl(-/- mouse inhibited cementum formation, causing root detachment consistent with premature tooth loss in the human condition hypophosphatasia, though cementoblast phenotype was unperturbed. Deficient PP(i in both Ank and Enpp1(-/- mice significantly increased cementum apposition and overall thickness more than 12-fold vs. controls, while dentin and cellular cementum were unaltered. Though PP(i regulators are widely expressed, cementoblasts selectively expressed greater ANK and NPP1 along the root surface, and dramatically increased ANK or NPP1 in models of reduced PP(i output, in compensatory fashion. In vitro mechanistic studies confirmed that under low PP(i mineralizing conditions, cementoblasts increased Ank (5-fold and Enpp1 (20-fold, while increasing PP(i inhibited mineralization and associated increases in Ank and Enpp1 mRNA. CONCLUSIONS: Results from these studies demonstrate a novel developmental regulation of acellular cementum, wherein cementoblasts tune cementogenesis by modulating

  9. Synthesis of high specific activity (1- sup 3 H) farnesyl pyrophosphate

    Energy Technology Data Exchange (ETDEWEB)

    Saljoughian, M.; Morimoto, H.; Williams, P.G.

    1991-08-01

    The synthesis of tritiated farnesyl pyrophosphate with high specific activity is reported. trans-trans Farnesol was oxidized to the corresponding aldehyde followed by reduction with lithium aluminium tritide (5%-{sup 3}H) to give trans-trans (1-{sup 3}H)farnesol. The specific radioactivity of the alcohol was determined from its triphenylsilane derivative, prepared under very mild conditions. The tritiated alcohol was phosphorylated by initial conversion to an allylic halide, and subsequent treatment of the halide with tris-tetra-n-butylammonium hydrogen pyrophosphate. The hydride procedure followed in this work has advantages over existing methods for the synthesis of tritiated farnesyl pyrophosphate, with the possibility of higher specific activity and a much higher yield obtained. 10 refs., 3 figs.

  10. Xanthohumol, a prenylated chalcone from beer hops, acts as an α-glucosidase inhibitor in vitro.

    Science.gov (United States)

    Liu, Ming; Yin, Hua; Liu, Ge; Dong, Jianjun; Qian, Zhonghua; Miao, Jinlai

    2014-06-18

    Xanthohumol (XN) is a unique prenylated flavonoid in hops (Humulus lupulus L.) and beer. XN alleviates hyperglycemia and has potential usage in the treatment of type 2 diabetes. In the present study, a series of in vitro experiments were performed to investigate whether XN was an effective inhibitor of α-glucosidase. The results showed that XN inhibited α-glucosidase in a reversible and noncompetitive manner, with an IC50 value of 8.8 μM and that XN inhibited the release of glucose from the maltose in the apical side of the Caco-2 cell monolayer. Fluorescence and circular dichroism spectra results indicated that XN directly bound to α-glucosidase and induced minor conformational changes of the enzyme. These results demonstrated that XN is a promising α-glucosidase inhibitor, which therefore could be used as functional food to alleviate postprandial hyperglycemia and as a potential candidate for the development of an antidiabetic agent.

  11. Antimicrobial prenylated benzoylphloroglucinol derivatives and xanthones from the leaves of Garcinia goudotiana.

    Science.gov (United States)

    Mahamodo, Sania; Rivière, Céline; Neut, Christel; Abedini, Amin; Ranarivelo, Heritiana; Duhal, Nathalie; Roumy, Vincent; Hennebelle, Thierry; Sahpaz, Sevser; Lemoine, Amélie; Razafimahefa, Dorothée; Razanamahefa, Bakonirina; Bailleul, François; Andriamihaja, Bakolinirina

    2014-06-01

    Bioassay-guided fractionation using antimicrobial assay of the crude acetonic extract of Garcinia goudotiana leaves and of its five partitions led to the isolation of two new prenylated benzoylphloroglucinol derivatives, goudotianone 1 (1) and goudotianone 2 (2), in addition to two known compounds including one xanthone, 1,3,7-trihydroxy-2-isoprenylxanthone (3), and one triterpenoid, friedelin (4). Their structures were elucidated on the basis of different spectroscopic methods, including extensive 1D- and 2D-NMR spectroscopy and mass spectrometry. The crude acetonic extract, the methylene chloride and ethyl acetate partitions, and some tested compounds isolated from this species (1-3) demonstrated selective significant antimicrobial activities against Gram-positive bacteria, in particular Staphylococcus lugdunensis, Enterococcus faecalis and Mycobacterium smegmatis. The potential cytotoxic activities of these extracts and compounds were evaluated against human colon carcinoma HT29 and human fetal lung fibroblast MRC5 cells. Copyright © 2014 Elsevier Ltd. All rights reserved.

  12. Flemingin-Type Prenylated Chalcones from the Sarawak Rainforest Plant Desmodium congestum.

    Science.gov (United States)

    Rees, Karlee A; Bermudez, Cindy; Edwards, David J; Elliott, Alysha G; Ripen, Jovita E; Seta, Cynthia; Huang, Johnny X; Cooper, Matthew A; Fraser, James A; Yeo, Tiong Chia; Butler, Mark S

    2015-08-28

    In an ongoing program to identify new anti-infective leads, an extract derived from whole plant material of Desmodium congestum collected in the Sarawak rainforest was found to have anti-MRSA activity. Bioassay-guided isolation led to the isolation of two new prenylated chalcones, 5'-O-methyl-3-hydroxyflemingin A (1) and 5'-O-methylflemingin C (2), which were closely related to the flemingins previously isolated from various Flemingia species. Chalcones 1 and 2, which were determined to be 4:6 enantiomeric mixtures by chiral HPLC, exhibited moderate activity against a panel of Gram-positive bacteria and were also cytotoxic to the HEK293 human embryonic kidney cell line.

  13. Prenylated Polyphenols from Clusiaceae and Calophyllaceae with Immunomodulatory Activity on Endothelial Cells.

    Science.gov (United States)

    Rouger, Caroline; Pagie, Sylvain; Derbré, Séverine; Le Ray, Anne-Marie; Richomme, Pascal; Charreau, Béatrice

    2016-01-01

    Endothelial cells (ECs) are key players in inflammation and immune responses involved in numerous pathologies. Although attempts were experimentally undertaken to prevent and control EC activation, drug leads and probes still remain necessary. Natural products (NPs) from Clusiaceous and Calophyllaceous plants were previously reported as potential candidates to prevent endothelial dysfunction. The present study aimed to identify more precisely the molecular scaffolds that could limit EC activation. Here, 13 polyphenols belonging to 5 different chemical types of secondary metabolites (i.e., mammea coumarins, a biflavonoid, a pyranochromanone acid, a polyprenylated polycyclic acylphloroglucinol (PPAP) and two xanthones) were tested on resting and cytokine-activated EC cultures. Quantitative and qualitative changes in the expression of both adhesion molecules (VCAM-1, ICAM-1, E-selectin) and major histocompatibility complex (MHC) molecules have been used to measure their pharmaceutical potential. As a result, we identified 3 mammea coumarins that efficiently reduce (up to >90% at 10 μM) both basal and cytokine-regulated levels of MHC class I, class II, MICA and HLA-E on EC surface. They also prevented VCAM-1 induction upon inflammation. From a structural point of view, our results associate the loss of the free prenyl group substituting mammea coumarins with a reduced cellular cytotoxicity but also an abrogation of their anti-inflammatory potential and a reduction of their immunosuppressive effects. A PPAP, guttiferone J, also triggers a strong immunomodulation but restricted to HLA-E and MHC class II molecules. In conclusion, mammea coumarins with a free prenyl group and the PPAP guttiferone J emerge as NPs able to drastically decrease both VCAM-1 and a set of MHC molecules and to potentially reduce the immunogenicity of the endothelium.

  14. Bis-Pyrano Prenyl Isoflavone Improves Glucose Homeostasis by Inhibiting Dipeptidyl Peptidase-4 in Hyperglycemic Rats.

    Science.gov (United States)

    Altenhofen, Delsi; da Luz, Gabrielle; Frederico, Marisa Jádna Silva; Venzke, Dalila; Brich, Mayara; Vigil, Silvana; Fröde, Tania Silvia; Linares, Carlos Eduardo Blanco; Pizzolatti, Moacir Geraldo; Silva, Fátima Regina Mena Barreto

    2017-01-01

    Isoflavones widely distributed in plants prevent diabetes. This study investigated the in vivo and in vitro effect of 3',4'-dihydroxy-6″,6″,6″',6″'-tetramethylbis(pyrano[2″,3″:5,6::2″',3″':7,8]isoflavone (bis-pyrano prenyl isoflavone) on glucose homeostasis in hyperglycemic rats. The ethyl acetate fraction from aerial parts of Polygala molluginifolia that contain isoflavones was assayed on glucose tolerance, on in vitro maltase activity and on protein glycation. The isoflavone bis-pyrano prenyl isolated from this fraction was investigated on glucose homeostasis. The in vivo action of the isoflavone exhibits an anti-hyperglycemic effect by improving glucose tolerance, augmenting the liver glycogen, inhibiting maltase activity, and stimulating glucagon-like peptide-1 (GLP-1) and insulin secretion. The in vitro isoflavone inhibits dipeptidyl peptidase-4 (DPP-4) activity since the glucose tolerance was improved in the presence of the isoflavone as much as sitagliptin, an inhibitor of DPP-4. However, the co-incubation with isoflavone and sitagliptin exhibited an additive anti-hyperglycemic action. The isoflavone increased the GLP-1 faster than the positive hyperglycemic group, which shows that the intestine is a potential target. Thus, to clarify the main site of action in which isoflavone improves glucose balance, the in vitro mechanism of action of this compound was tested in intestine using calcium influx as a trigger for the signal pathways for GLP-1 secretion. The isoflavone stimulates calcium influx in intestine and its mechanism involves voltage-dependent calcium channels, phospholipase C, protein kinase C, and stored calcium contributing for GLP-1 secretion. In conclusion, the isoflavone regulates glycaemia by acting mainly in a serum target, the DPP-4 inhibitor. Furthermore, the long-term effect of isoflavone prevents protein glycation. J. Cell. Biochem. 118: 92-103, 2017. © 2016 Wiley Periodicals, Inc.

  15. Prenylated Polyphenols from Clusiaceae and Calophyllaceae with Immunomodulatory Activity on Endothelial Cells

    Science.gov (United States)

    Rouger, Caroline; Pagie, Sylvain; Derbré, Séverine; Le Ray, Anne-Marie; Richomme, Pascal; Charreau, Béatrice

    2016-01-01

    Endothelial cells (ECs) are key players in inflammation and immune responses involved in numerous pathologies. Although attempts were experimentally undertaken to prevent and control EC activation, drug leads and probes still remain necessary. Natural products (NPs) from Clusiaceous and Calophyllaceous plants were previously reported as potential candidates to prevent endothelial dysfunction. The present study aimed to identify more precisely the molecular scaffolds that could limit EC activation. Here, 13 polyphenols belonging to 5 different chemical types of secondary metabolites (i.e., mammea coumarins, a biflavonoid, a pyranochromanone acid, a polyprenylated polycyclic acylphloroglucinol (PPAP) and two xanthones) were tested on resting and cytokine-activated EC cultures. Quantitative and qualitative changes in the expression of both adhesion molecules (VCAM-1, ICAM-1, E-selectin) and major histocompatibility complex (MHC) molecules have been used to measure their pharmaceutical potential. As a result, we identified 3 mammea coumarins that efficiently reduce (up to >90% at 10 μM) both basal and cytokine-regulated levels of MHC class I, class II, MICA and HLA-E on EC surface. They also prevented VCAM-1 induction upon inflammation. From a structural point of view, our results associate the loss of the free prenyl group substituting mammea coumarins with a reduced cellular cytotoxicity but also an abrogation of their anti-inflammatory potential and a reduction of their immunosuppressive effects. A PPAP, guttiferone J, also triggers a strong immunomodulation but restricted to HLA-E and MHC class II molecules. In conclusion, mammea coumarins with a free prenyl group and the PPAP guttiferone J emerge as NPs able to drastically decrease both VCAM-1 and a set of MHC molecules and to potentially reduce the immunogenicity of the endothelium. PMID:27907087

  16. Biosynthesis of monoterpenes. Enantioselectivity in the enzymatic cyclization of (+)- and (-)-linalyl pyrophosphate to (+)- and (-)-pinene and (+)- and (-)-camphene

    Energy Technology Data Exchange (ETDEWEB)

    Croteau, R.; Satterwhite, D.M.; Cane, D.E.; Chang, C.C.

    1988-07-25

    Cyclase I from Salvia officinalis leaf catalyzes the conversion of geranyl pyrophosphate to the stereo-chemically related bicyclic monoterpenes (+)-alpha-pinene and (+)-camphene and to lesser quantities of monocyclic and acyclic olefins, whereas cyclase II from this plant tissue converts the same acyclic precursor to (-)-alpha-pinene, (-)-beta-pinene and (-)-camphene as well as to lesser amounts of monocyclics and acyclics. These antipodal cyclizations are considered to proceed by the initial isomerization of the substrate to the respective bound tertiary allylic intermediates (-)-(3R)- and (+)-(3S)-linalyl pyrophosphate. ((3R)-8,9-14C,(3RS)-1E-3H)Linalyl pyrophosphate (3H:14C = 5.14) was tested as a substrate with both cyclases to determine the configuration of the cyclizing intermediate. This substrate with cyclase I yielded alpha-pinene and camphene with 3H:14C ratios of 3.1 and 4.2, respectively, indicating preferential, but not exclusive, utilization of the (3R)-enantiomer. With cyclase II, the doubly labeled substrate gave bicyclic olefins with 3H:14C ratios of from 13 to 20, indicating preferential, but not exclusive, utilization of the (3S)-enantiomer in this case. (3R)- and (3S)-(1Z-3H)linalyl pyrophosphate were separately compared to the achiral precursors (1-3H)geranyl pyrophosphate and (1-3H)neryl pyrophosphate (cis-isomer) as substrates for the cyclizations. With cyclase I, geranyl, neryl, and (3R)-linalyl pyrophosphate gave rise exclusively to (+)-alpha-pinene and (+)-camphene, whereas (3S)-linayl pyrophosphate produced, at relatively low rates, the (-)-isomers. With cyclase II, geranyl, neryl, and (3S)-linalyl pyrophosphate yielded exclusively the (-)-isomer series, whereas (3R)-linalyl pyrophosphate afforded the (+)-isomers at low rates.

  17. THE CLINICAL MANIFESTATIONS OF CALCIUM PYROPHOSPHATE CRYSTAL DEPOSITION DISEASE

    Directory of Open Access Journals (Sweden)

    F. M. Kudaeva

    2014-01-01

    Full Text Available Objective: to provide the clinical characteristics of joint injury in patients with calcium pyrophosphate crystal (CPC deposition disease.Subjects and methods. The trial enrolled 68 patients (43 women, 25 men with a verified diagnosis of CPC deposition disease. Their mean age was 60.2±11.8 years and disease duration was 7.5±6.4 years. Examination revealed the presence of arthritis and arthralgias. Polarizing microscopy with an Olympus CX31-P compensator was used to detectcrystals in synovial fluid. X-ray study of the knee joints was performed in the anteroposterior and lateral projections and that of the hand joints was in the frontal projection, Ultrasonography (USG of the knee and wrist joints was done using a GE Voluson-I transducer.Results. A concurrence of arthritis and arthralgias was noted in 37 (54% patients; 24 (36% patients had arthralgias only; 7 (10% had arthritis only. Arthritis affecting the knee, wrist, ankle, and first metacarpophalangeal joints was observed in 53, 15, 12, and 6% of cases, respectively. There was acute arthritis in 18% of the patients and chronic arthritis in 39%; the rate of CPC osteoarthrosis was 43%. Joint USG diagnosed knee and wrist joint chondrocalcinosis in 94 and 56% of the patients, respectively. USG could reveal asymptomatic wrist joint chondrocalcinosis significantly more often (in 56 and 17% of the patients, respectively; p = 0.008. Besides, USG could visualize synovitis in the knee joints in 88% of the patients with isolated arthralgias in them and synovitis in the wrinkle joints in 52% of the patients without clinical signs of inflammation in them.Conclusion. Osteoarthrosis is the most common form of CPC deposition disease. Knee joints in this disease are most frequently involved. Joint USG is of more informative value in detecting chondrocalcinosis than X-ray study; USG can also identify synovitis in the intact joints.

  18. The position of prenylation of isoflavonoids and stilbenoids from legumes (Fabaceae) modulates the antimicrobial activity against Gram positive pathogens.

    Science.gov (United States)

    Araya-Cloutier, Carla; den Besten, Heidy M W; Aisyah, Siti; Gruppen, Harry; Vincken, Jean-Paul

    2017-07-01

    The legume plant family (Fabaceae) is a potential source of antimicrobial phytochemicals. Molecular diversity in phytochemicals of legume extracts was enhanced by germination and fungal elicitation of seven legume species, as established by RP-UHPLC-UV-MS. The relationship between phytochemical composition, including different types of skeletons and substitutions, and antibacterial properties of extracts was investigated. Extracts rich in prenylated isoflavonoids and stilbenoids showed potent antibacterial activity against Listeria monocytogenes and methicillin-resistant Staphylococcus aureus at concentrations between 0.05 and 0.1% (w/v). Prenylated phenolic compounds were significantly (plegume seedlings can serve multiple purposes, e.g. as phytoestrogens they can provide health benefits and as natural antimicrobials they offer preservation of foods.

  19. Anti-respiratory syncytial virus prenylated dihydroquinolone derivatives from the gorgonian-derived fungus Aspergillus sp. XS-20090B15.

    Science.gov (United States)

    Chen, Min; Shao, Chang-Lun; Meng, Hong; She, Zhi-Gang; Wang, Chang-Yun

    2014-12-26

    Two new prenylated dihydroquinolone derivatives, 22-O-(N-Me-l-valyl)aflaquinolone B (1) and 22-O-(N-Me-l-valyl)-21-epi-aflaquinolone B (2), and two known analogues, aflaquinolones A (3) and D (or a diastereomer of D, 4), were isolated from the mycelia of a gorgonian-derived Aspergillus sp. fungus. The structures of the new compounds were elucidated by spectroscopic methods, ECD spectra, Marfey's method, and chemical conversion. Compounds 1 and 2 display an unusual esterification of N-Me-l-Val to the side-chain prenyl group. Compound 2 exhibited outstanding anti-RSV activity with an IC50 value of 42 nM, approximately 500-fold stronger than that of the positive control ribavirin (IC50 = 20 μM), and showed a comparatively higher therapeutic ratio (TC50/IC50 = 520).

  20. Tc-99m pyrophosphate scanning after ischemic exercise in McArdle's disease

    Energy Technology Data Exchange (ETDEWEB)

    Uno, Hideaki; Kawano, Keizo; Yukawa, Susumu; Nomoto, Hiroshi (Wakayama Medical Coll. (Japan))

    1982-03-01

    In order to clarify the mechanism of muscle contracture induced by ischemic exercise in a patient with McArdle's disease, bone scanning with Tc-99m pyrophosphate was performed. The clinical diagnosis was established in the patient based on the biochemical examinations of skeletal muscle biopsy. Ischemic exercise was done initially on the left forearm and then 20 hours later on the right forearm. Two hours later, 15 mCi of Tc-99m pyrophosphate was infused through the left antecubital vein. Exactly 4 hours later, a conventional bone scanning was carried out. In the patient with McArdle's disease, muscle contracture developed in both forearms during the ischemic exercise. Conventional bone scanning showed increased Tc-99m pyrophosphate labeling of the right forearm muscles at 2 hours after ischemic exercise. However, increased labeling of the left forearm muscles was not found at 22 hours after ischemic exercise. In the control, no muscle contracture developed during ischemic exercise and bone scan showed no increase in Tc-99m pyrophosphate labeling in the antebrachial region. These findings suggest that the basis of muscle contracture appears to be an increased concentration of Ca in muscle cells due to a failure of sarcoplasmic reticulum to reaccumulate Ca at ischemic exercise.

  1. Hyaline cartilage involvement in patients with gout and calcium pyrophosphate deposition disease. An ultrasound study.

    Science.gov (United States)

    Filippucci, E; Riveros, M Gutierrez; Georgescu, D; Salaffi, F; Grassi, W

    2009-02-01

    The main aim of the present study was to determine the sensitivity, specificity and accuracy of ultrasonography (US) in detecting monosodium urate and calcium pyrophosphate dihydrate crystals deposits at knee cartilage level using clinical definite diagnosis as standard reference. A total of 32 patients with a diagnosis of gout and 48 patients with pyrophosphate arthropathy were included in the study. Fifty-two patients with rheumatoid arthritis (RA), psoriatic arthritis or osteoarthritis (OA) were recruited as disease controls. All diagnoses were made using an international clinical criterion. US examinations were performed by an experienced sonographer, blind to clinical and laboratory data. Hyaline cartilage was assessed to detect two US findings recently indicated as indicative of crystal deposits: hyperechoic enhancement of the superficial margin of the hyaline cartilage and hyperechoic spots within the cartilage layer not generating a posterior acoustic shadow. Hyperechoic enhancement of the chondrosynovial margin was found in at least one knee of 14 out of 32 (43.7%) patients with gout and in a single knee of only one patient affected by pyrophosphate arthropathy (specificity=99%). Intra-cartilaginous hyperechoic spots were detected in at least one knee of 33 out of 48 (68.7%) patients with pyrophosphate arthropathy and in two disease controls one with OA and the second with RA (specificity=97.6%). The results of the present study indicate that US may play a relevant role in distinguishing cartilage involvement in patients with crystal-related arthropathy. The selected US findings were found to be highly specific.

  2. Imaging organophosphate and pyrophosphate sequestration on brucite by in situ atomic force microscopy

    NARCIS (Netherlands)

    Wang, Lijun; Putnis, Christine V; King, Helen E; Hövelmann, Jörn; Ruiz-Agudo, Encarnación; Putnis, Andrew

    2016-01-01

    In order to evaluate the organic phosphorus (OP) and pyrophosphate (PyroP) cycle and their fate in the environment, it is critical to understand the effects of mineral interfaces on the reactivity of adsorption and precipitation of OP and PyroP. Here, in situ atomic force microscopy (AFM) is used to

  3. A highly sensitive gold nanoparticle-based colorimetric probe for pyrophosphate using a competition assay approach.

    Science.gov (United States)

    Kim, Sudeok; Eom, Min Sik; Kim, Seung Kyung; Seo, Seong Hyeok; Han, Min Su

    2013-01-01

    In this study, a mixture of [Zn(2)(1,3-bis[bis(2-pyridylmethyl)aminomethyl]benzene)](4+) ([Zn(2)(BBPAB)](4+)) and 11-mercaptoundecylphosphoric acid functionalized gold nanoparticles (Phos-AuNPs) is shown to be a highly sensitive colorimetric probe that can easily detect pyrophosphate (PPi) at less than 200 nM with the naked eye.

  4. Inositol pyrophosphates regulate RNA polymerase I-mediated rRNA transcription in Saccharomyces cerevisiae.

    Science.gov (United States)

    Thota, Swarna Gowri; Unnikannan, C P; Thampatty, Sitalakshmi R; Manorama, R; Bhandari, Rashna

    2015-02-15

    Ribosome biogenesis is an essential cellular process regulated by the metabolic state of a cell. We examined whether inositol pyrophosphates, energy-rich derivatives of inositol that act as metabolic messengers, play a role in ribosome synthesis in the budding yeast, Saccharomyces cerevisiae. Yeast strains lacking the inositol hexakisphosphate (IP6) kinase Kcs1, which is required for the synthesis of inositol pyrophosphates, display increased sensitivity to translation inhibitors and decreased protein synthesis. These phenotypes are reversed on expression of enzymatically active Kcs1, but not on expression of the inactive form. The kcs1Δ yeast cells exhibit reduced levels of ribosome subunits, suggesting that they are defective in ribosome biogenesis. The rate of rRNA synthesis, the first step of ribosome biogenesis, is decreased in kcs1Δ yeast strains, suggesting that RNA polymerase I (Pol I) activity may be reduced in these cells. We determined that the Pol I subunits, A190, A43 and A34.5, can accept a β-phosphate moiety from inositol pyrophosphates to undergo serine pyrophosphorylation. Although there is impaired rRNA synthesis in kcs1Δ yeast cells, we did not find any defect in recruitment of Pol I on rDNA, but observed that the rate of transcription elongation was compromised. Taken together, our findings highlight inositol pyrophosphates as novel regulators of rRNA transcription.

  5. Xanthohumol, a Prenylated Chalcone from Hops, Inhibits the Viability and Stemness of Doxorubicin-Resistant MCF-7/ADR Cells

    OpenAIRE

    Ming Liu; Hua Yin; Xiaokun Qian; Jianjun Dong; Zhonghua Qian; Jinlai Miao

    2016-01-01

    Xanthohumol is a unique prenylated flavonoid in hops (Humulus lupulus L.) and beer. Xanthohumol has been shown to possess a variety of pharmacological activities. There is little research on its effect on doxorubicin-resistant breast cancer cells (MCF-7/ADR) and the cancer stem-like cells exiting in this cell line. In the present study, we investigate the effect of xanthohumol on the viability and stemness of MCF-7/ADR cells. Xanthohumol inhibits viability, induces apoptosis, and arrests the ...

  6. Xanthohumol, a Prenylated Flavonoid from Hops (Humulus lupulus), Prevents Platelet Activation in Human Platelets.

    Science.gov (United States)

    Lee, Ye-Ming; Hsieh, Kuo-Hsien; Lu, Wan-Jung; Chou, Hsiu-Chu; Chou, Duen-Suey; Lien, Li-Ming; Sheu, Joen-Rong; Lin, Kuan-Hung

    2012-01-01

    Xanthohumol is the principal prenylated flavonoid in the hop plant (Humulus lupulus L.). Xanthohumol was found to be a very potent cancer chemopreventive agent through regulation of diverse mechanisms. However, no data are available concerning the effects of xanthohumol on platelet activation. The aim of this paper was to examine the antiplatelet effect of xanthohumol in washed human platelets. In the present paper, xanthohumol exhibited more-potent activity in inhibiting platelet aggregation stimulated by collagen. Xanthohumol inhibited platelet activation accompanied by relative [Ca(2+)](i) mobilization, thromboxane A(2) formation, hydroxyl radical (OH(●)) formation, and phospholipase C (PLC)γ2, protein kinase C (PKC), mitogen-activated protein kinase (MAPK), and Akt phosphorylation. Neither SQ22536, an inhibitor of adenylate cyclase, nor ODQ, an inhibitor of guanylate cyclase, reversed the xanthohumol-mediated inhibitory effect on platelet aggregation. Furthermore, xanthohumol did not significantly increase nitrate formation in platelets. This study demonstrates for the first time that xanthohumol possesses potent antiplatelet activity which may initially inhibit the PI3-kinase/Akt, p38 MAPK, and PLCγ2-PKC cascades, followed by inhibition of the thromboxane A(2) formation, thereby leading to inhibition of [Ca(2+)](i) and finally inhibition of platelet aggregation. Therefore, this novel role of xanthohumol may represent a high therapeutic potential for treatment or prevention of cardiovascular diseases.

  7. Xanthohumol, a Prenylated Flavonoid from Hops (Humulus lupulus, Prevents Platelet Activation in Human Platelets

    Directory of Open Access Journals (Sweden)

    Ye-Ming Lee

    2012-01-01

    Full Text Available Xanthohumol is the principal prenylated flavonoid in the hop plant (Humulus lupulus L.. Xanthohumol was found to be a very potent cancer chemopreventive agent through regulation of diverse mechanisms. However, no data are available concerning the effects of xanthohumol on platelet activation. The aim of this paper was to examine the antiplatelet effect of xanthohumol in washed human platelets. In the present paper, xanthohumol exhibited more-potent activity in inhibiting platelet aggregation stimulated by collagen. Xanthohumol inhibited platelet activation accompanied by relative [Ca2+]i mobilization, thromboxane A2 formation, hydroxyl radical (OH● formation, and phospholipase C (PLCγ2, protein kinase C (PKC, mitogen-activated protein kinase (MAPK, and Akt phosphorylation. Neither SQ22536, an inhibitor of adenylate cyclase, nor ODQ, an inhibitor of guanylate cyclase, reversed the xanthohumol-mediated inhibitory effect on platelet aggregation. Furthermore, xanthohumol did not significantly increase nitrate formation in platelets. This study demonstrates for the first time that xanthohumol possesses potent antiplatelet activity which may initially inhibit the PI3-kinase/Akt, p38 MAPK, and PLCγ2-PKC cascades, followed by inhibition of the thromboxane A2 formation, thereby leading to inhibition of [Ca2+]i and finally inhibition of platelet aggregation. Therefore, this novel role of xanthohumol may represent a high therapeutic potential for treatment or prevention of cardiovascular diseases.

  8. Antiinvasive effect of xanthohumol, a prenylated chalcone present in hops (Humulus lupulus L.) and beer.

    Science.gov (United States)

    Vanhoecke, Barbara; Derycke, Lara; Van Marck, Veerle; Depypere, Herman; De Keukeleire, Denis; Bracke, Marc

    2005-12-20

    The female inflorescences of the hop plant (Humulus lupulus L.) are essential during brewing to add taste and flavor to beer and to stabilize beer foam. Xanthohumol, the main prenylated chalcone in hops, was investigated for its antiinvasive activity on human breast cancer cell lines (MCF-7 and T47-D) in vitro. Xanthohumol was able to inhibit the invasion of MCF-7/6 cells at 5 microM in the chick heart invasion assay and of T47-D cells in the collagen invasion assay. Xanthohumol inhibited growth of MCF-7/6 and T47-D cells, but not of chick heart cells. Moreover, it induced apoptosis of these tumor cells as demonstrated by the cleavage of nuclear PARP after 48 hr treatment. To probe the mechanism of the antiinvasive effect of xanthohumol, involvement of the E-cadherin/catenin invasion-suppressor complex was investigated. An aggregation assay demonstrated stimulation of aggregation of MCF-7/6 cells in the presence of 5 microM xanthohumol and this could be completely inhibited by an antibody against E-cadherin. Xanthohumol upregulates the function of the E-cadherin/catenin complex and inhibits invasion in vitro, indicating a possible role as an antiinvasive agent in vivo as well.

  9. O-prenylated acridone alkaloids from the stems of Balsamocitrus paniculata (Rutaceae).

    Science.gov (United States)

    Happi, Emmanuel Ngeufa; Waffo, Alain François; Wansi, Jean Duplex; Ngadjui, Bonaventure Tchaleu; Sewald, Norbert

    2011-06-01

    Two new O-prenylated acridone alkaloids, balsacridone A (1) and B (2), together with eighteen known compounds were isolated from the methanol extract from the stems of Balsamocitrus paniculata, a Cameroonian medicinal plant. The structures of all compounds were determined by comprehensive analyses of their 1D and 2D NMR, mass spectral (EI and ESI) data, and chemical reactions. N-methyl-6-methoxybenzoxazolinone (16) was isolated for the first time from a natural source while compounds 13, 14, and 15 for the first time from this genus. Pure compounds were tested for their activity against bacteria, fungi, and plant pathogen oomycetes, using the paper disk agar diffusion assay. The agar diffusion test delivered low to missing antimicrobial activities, corresponding to MICs > 1 mg/mL. However, compounds 1-15 exhibited a strong suppressive effect on phagocytosis response upon activation with serum opsonized zymosan in the range of IC50 = 0.5-7.2 μM, and the acridone alkaloids (1-5), N-trans-p-coumaroyltyramine (13), and N-trans-pcoumaroyloctopamine (14) displayed weak cytotoxic activity against the human Caucasian prostate adenocarcinoma cell line PC-3, with IC₅₀ values ranging from 69.8 to 99.0 μM.

  10. Prenylated flavonoids from Artocarpus altilis: antioxidant activities and inhibitory effects on melanin production.

    Science.gov (United States)

    Lan, Wen-Chun; Tzeng, Cheng-Wei; Lin, Chun-Ching; Yen, Feng-Lin; Ko, Horng-Huey

    2013-05-01

    Flavonoids, 10-oxoartogomezianone (1), 8-geranyl-3-(hydroxyprenyl)isoetin (2), hydroxyartoflavone A (3), isocycloartobiloxanthone (4), and furanocyclocommunin (5), together with 12 known compounds, were isolated from heartwood and cortex of Artocarpus altilis, and their structures were identified by comparing their spectra with those of similar compounds. To identify natural antioxidants and whitening agents, the ability of these prenylated flavonoids was assessed to scavenge the 1,1-diphenyl-2-picrylhydrazyl radical (DPPH), the 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS(+·)) radical cation, and the superoxide anion (O2(-·)), and their abilities to inhibit tyrosinase and melanin production. It was found that compounds 3, 4, and artoflavone A (15) had moderate DPPH(·)-scavenging activity, whereas compound 4 exhibited significant ABTS(+·)-scavenging activity, and that norartocarpetin (7) and artogomezianone (8) exhibited moderate ABTS(+·)-scavenging activity, with compounds 2, 7, and artocarpin (6) displaying good superoxide anion-scavenging activity. In addition, compounds 7, 8, cudraflavone A (14), and artonin M (17), inhibited melanin production by strongly suppressing tyrosinase activity. Compound 6 reduced the melanin content without inhibiting tyrosinase activity. These results suggest that flavonoids isolated from A. altilis may be candidate antioxidants and/or skin-whitening agents. However, further investigations are required to determine their mechanisms of action. Copyright © 2013 Elsevier Ltd. All rights reserved.

  11. Prenyl Ammonium Salts - New Carriers for Gene Delivery: A B16-F10 Mouse Melanoma Model.

    Directory of Open Access Journals (Sweden)

    Emilia Grecka

    Full Text Available Prenyl ammonium iodides (Amino-Prenols, APs, semi-synthetic polyprenol derivatives were studied as prospective novel gene transfer agents.AP-7, -8, -11 and -15 (aminoprenols composed of 7, 8, 11 or 15 isoprene units, respectively were examined for their capacity to form complexes with pDNA, for cytotoxicity and ability to transfect genes to cells.All the carriers were able to complex DNA. The highest, comparable to commercial reagents, transfection efficiency was observed for AP-15. Simultaneously, AP-15 exhibited the lowest negative impact on cell viability and proliferation-considerably lower than that of commercial agents. AP-15/DOPE complexes were also efficient to introduce pDNA to cells, without much effect on cell viability. Transfection with AP-15/DOPE complexes influenced the expression of a very few among 44 tested genes involved in cellular lipid metabolism. Furthermore, complexes containing AP-15 and therapeutic plasmid, encoding the TIMP metallopeptidase inhibitor 2 (TIMP2, introduced the TIMP2 gene with high efficiency to B16-F10 melanoma cells but not to B16-F10 melanoma tumors in C57BL/6 mice, as confirmed by TIMP2 protein level determination.Obtained results indicate that APs have a potential as non-viral vectors for cell transfection.

  12. Formation of pyrophosphate, tripolyphosphate, and phosphorylimidazole with the thioester, N, S-diacetylcysteamine, as the condensing agent. [molecular evolution

    Science.gov (United States)

    Weber, A. L.

    1981-01-01

    The formation of pyrophosphate, tripolyphosphate and phosphorylimidazole from orthophosphate in the presence of the thioester N, S-diacetylcysteamine is reported. Reactions performed with 0.20 M orthophosphate and 0.20 M N, S-diacetylcysteamine in 0.40 M imidazole under drying conditions at 50 C yielded pyrophosphate and tripolyphosphate after six days in the presence and absence of divalent metal ions. Reactions carried out at ambient temperature yielded phosphorylimidazole in the presence or absence of 0.05 M MgCl2, phosphorylimidazole and pyrophosphate in the presence of 0.05 M CaCl2, and pyrophosphate and tripolyphosphate in the presence of 0.15 M CaCl2. Such reactions represent potential pathways for the formation of energy-rich compounds providing free energy for use in prebiotic biopolymer synthesis.

  13. Use of Genomics To Identify Bacterial Undecaprenyl Pyrophosphate Synthetase: Cloning, Expression, and Characterization of the Essential uppS Gene

    OpenAIRE

    Apfel, Christian M.; Takács, Béla; Fountoulakis, Michael; Stieger, Martin; Keck, Wolfgang

    1999-01-01

    The prenyltransferase undecaprenyl pyrophosphate synthetase (di-trans,poly-cis-decaprenylcistransferase; EC 2.5.1.31) was purified from the soluble fraction of Escherichia coli by TSK-DEAE, ceramic hydroxyapatite, TSK-ether, Superdex 200, and heparin-Actigel chromatography. The protein was labeled with the photolabile analogue of the farnesyl pyrophosphate analogue (E,E)-[1-3H]-(2-diazo-3-trifluoropropionyloxy)geranyl diphos-phate and was detected on a sodium dodecyl sulfate-polyacrylamide ge...

  14. Hardness analysis and morphological characterization of copper-zinc alloys produced in pyrophosphate-based electrolytes

    Directory of Open Access Journals (Sweden)

    Lilian Ferreira de Senna

    2005-09-01

    Full Text Available In this work, copper-zinc alloy coatings on mild steel substrates were obtained in nontoxic pyrophosphate-based electrolytes, at room temperature and under continuous current. The effects of bath composition and current density on the hardness of the coatings, as well as on their morphologies, were evaluated. The results showed that the electrolyte composition, and the use of stress relieving additives strongly influence the hardness of the coatings, while the current density directly affect their morphology. Hence, for a current density of 116 A/m², copper-zinc alloy deposits with no pores or cracks were produced in a pyrophosphate-based electrolyte, especially when allyl alcohol was added to the solution.

  15. Pyrophosphate selective fluorescent chemosensors: cascade recognition of nuclear stain mimicking DAPI.

    Science.gov (United States)

    Goswami, Shyamaprosad; Das, Avijit Kumar; Pakhira, Bholanath; Basu Roy, Sohini; Maity, Anup Kumar; Saha, Partha; Sarkar, Sabyasachi

    2014-09-07

    A new zinc(ii) complex with a condensed hydroxynaphthyl pyridine (SPHN) as the coordinated ligand has been synthesized for the selective recognition of pyrophosphate (PPi) over other anions including phosphate in a mixed aqueous solution. The fluorescence enhancement of SPHN in association with Zn(2+) ions is quenched in the presence of intracellular pyrophosphate. This phenomenon is utilized in the construction of a logic gate. The binding of SPHN with Zn(2+) and its displacement by PPi have been established by photophysical investigation and supported by the DFT level of studies. The development of blue fluorescence in the {} complex upon binding of zinc with is shown to be useful as a nucleus marker in a cell similar to the commercially available staining compound, DAPI (diamino-2-phenylindole).

  16. Calcium pyrophosphate dihydrate deposition disease (CPPD/Pseudogout of the temporomandibular joint - FNA findings and microanalysis.

    Directory of Open Access Journals (Sweden)

    Naqvi Asghar

    2008-01-01

    Full Text Available We report a case of a Calcium pyrophosphate dihydrate deposition disease (CPPD presenting as a mass in the parotid and temporomandibular joint (TMJ that simulated a parotid tumor. A 35 year-old man presented with pain in the left ear area. A CT Scan of the area showed a large, calcified mass surrounding the left condylar head, and extending into the infratemporal fossa. FNA of the mass showed birefringent crystals, most of which were rhomboid with occasional ones being needle shaped, embedded in an amorphous pink substance. Scanning electron microscopy (SEM with energy dispersive x-ray spectroscopy (EDS of these crystals showed peaks corresponding to calcium and phosphorus. SEM/EDS is a rapid method of diagnosing calcium pyrophosphate dihydrate deposition disease (CPPD and an alternative to more commonly used method of special staining of cell block sections coupled with polarizing microscopy.

  17. cDNA cloning, chromosome mapping and expression characterization of human geranylgeranyl pyrophosphate synthase

    Institute of Scientific and Technical Information of China (English)

    赵勇[1; 余龙[2; 高洁[3; 付强[4; 华益民[5; 张宏来[6; 赵寿元[7

    2000-01-01

    Geranylgeranyl pyrophosphate (GGPP) mainly participates in post-translational modification for various proteins including Rho/Rac, Rap and Rab families, as well as in regulation for cell apoptosis. Geranylgeranyl pyrophosphate synthase (GGPPS), which catalyzes the condensation reaction between farnesyl diphosphate and isopentenyl diphosphate, is the key enzyme for synthesizing GGPP. We report the isolation of a gene transcript showing high homology with Drosophila GGPPS cDNA. The transcript is 1 466 bp in length and contains an intact open reading frame (ORF) ranging from nt 239 to 1 138. This ORF encodes a deduced protein of 300 residues with calculated molecular weight of 35 ku. The deduced protein shows 57.5% identity and 75% similarity with Drosophila GGPPS, and contains five characteristic domains of prenyltransferases. Northern hybridization revealed that human GGPPS was expressed highest in heart, and moderately in spleen, testis, brain, placenta, lung, liver, skeletal muscle, kidney and pancreas

  18. Repeptization by dissolution in a colloidal system of iron(III) pyrophosphate.

    Science.gov (United States)

    van Leeuwen, Y Mikal; Velikov, Krassimir P; Kegel, Willem K

    2012-12-04

    Repeptization (redispersion) from an aggregated state is usually only possible in charge-stabilized colloidal systems if the system is either coagulated in the secondary minimum of the interaction potential or if the system cannot settle completely into the primary minimum. In this work, we analyze the zeta potential, conductivity, and long-term stability of colloidal systems of iron(III) pyrophosphate and surprisingly find that the system seems to defy conventional wisdom as it can be repeptized from its coagulated state regardless of aging time and background ions. Moreover, after having been stored for up to a month in 2 M NaCl, dialysis of iron pyrophosphate will yield a colloidal dispersion that is actually stable for a longer period of time than a fresh system with background electrolyte removed.

  19. Recognition of reversible and irreversible myocardial injury by technetium pyrophosphate extraction kinetics

    Energy Technology Data Exchange (ETDEWEB)

    Silva, R.; Chen, Y.F.; Sell, T.L.; Lowe, J.E.; Jones, R.H.

    1987-07-01

    The need for a more accurate method of detecting episodes of myocardial ischemia during cardiac operations, particularly during the ischemic arrest interval, prompted us to investigate the usefulness of measuring the active extraction of technetium pyrophosphate in identifying and quantitating ischemic injury. Twenty-four adult mongrel dogs were subjected to cardiopulmonary bypass, and normothermic global ischemia was induced by cross-clamping the proximal aorta. Technetium pyrophosphate (1 mCi) was injected through a standard cardioplegia line with normal saline, simulating administration of cardioplegic solution, upon placement of the aortic cross-clamp (time 0), at 15, 30, 45, and 60 minutes of global ischemia, and with the onset and completion of ischemic contracture. Radioactive counts were recorded over the heart at 1 second intervals, and the extraction fraction and half-time of clearance were calculated. The extraction fraction increased from 0.22 at time 0 to 0.58 at 15 minutes, 0.82 at 30 minutes, 0.85 at 45 minutes, and 0.91 at 60 minutes. The halftime increased from a baseline of 114 seconds (time 0) to a maximum of 321 seconds at 60 minutes of ischemia. The onset and completion of ischemic contracture showed a return toward baseline of both the extraction fraction and halftime of clearance, with an extraction fraction of 0.44 and 0.46 and a halftime of 135 and 133 seconds, respectively. These data clearly show that reversible myocardial injury increased the extraction and reduced the clearance of technetium pyrophosphate and that the magnitude of change related to the extent of injury. The progression to irreversible myocardial injury decreased the active extraction of technetium pyrophosphate. This simple procedure for real-time documentation of myocardial injury promises to provide easily obtainable endpoints of injury for use during cardiac operations in humans.

  20. PYROPHOSPHATE ARTHROPATHY IS A RHEUMATOLOGICAL ICEBERG SYNDROME: TIME TO REASSESS ITS IMPORTANCE IN JOINT DISEASES

    Directory of Open Access Journals (Sweden)

    Viktoria Georgiyevna Barskova

    2010-06-01

    Full Text Available The paper provides the present views of the epidemiology, pathogenesis, diagnosis, and classification of pyrophosphate arthropathy (PPA. It describes a morphological study of the structure of the knee joint after total prosthetics in a patient diagnosed as having osteoarthrosis. Reasons for low detection rates of the disease are considered. Difficulties in the laboratory and instrumental diagnosis of PPA are analyzed in detail.

  1. PYROPHOSPHATE ARTHROPATHY IS A RHEUMATOLOGICAL ICEBERG SYNDROME: TIME TO REASSESS ITS IMPORTANCE IN JOINT DISEASES

    Directory of Open Access Journals (Sweden)

    Viktoria Georgiyevna Barskova

    2010-01-01

    Full Text Available The paper provides the present views of the epidemiology, pathogenesis, diagnosis, and classification of pyrophosphate arthropathy (PPA. It describes a morphological study of the structure of the knee joint after total prosthetics in a patient diagnosed as having osteoarthrosis. Reasons for low detection rates of the disease are considered. Difficulties in the laboratory and instrumental diagnosis of PPA are analyzed in detail.

  2. Crystal arthritides - gout and calcium pyrophosphate arthritis : Part 1: Epidemiology and pathophysiology.

    Science.gov (United States)

    Schlee, S; Bollheimer, L C; Bertsch, T; Sieber, C C; Härle, P

    2017-02-23

    Gout and calcium pyrophosphate deposition disease (CPPD, pseudogout) are still the most frequent inflammatory arthritides in multimorbid elderly patients. Gout and CPPD are different diseases and based on different pathophysiological principles. Gout is closely associated with the metabolic syndrome and is an independent risk factor for cardiovascular mortality. The prevalence of asymptomatic hyperuricemia is estimated to be 10-20% of adults in industrial nations and prevalence is strongly associated with age. More than 7% of persons aged over 65 years suffer from clinically manifest gout. The underlying pathophysiological principle is an imbalance between the formation and elimination of uric acid. The degradation of the purine bases adenine and guanosine to uric acid is catalysed by xanthine oxidase and genetic polymorphisms and mutations play an important role in absorption and excretion processes. Furthermore, carrier proteins, such as URAT-1 or OAT-4 also have an influence on these processes. An imbalance of the physiological processes results in the solubility product being exceeded, which in consequence leads to crystallization of urate. This induces a cascade of massive inflammatory reactions at the molecular and cellular level with the activation of cytokines. The inflammatory process can be stopped by neutrophil extracellular traps (NETs) that modulate aggregation and degradation of chemokines and cytokines and partitioning of crystallized urate against immune cells. Calcium pyrophosphate dehydrate (CPP) crystals are formed in the cartilage and CPP deposition can be found in 30% of people aged over 80 years. Inorganic pyrophosphate (PPi) is synthesized in chondrocytes and plays an important part in the formation of calcium pyrophosphate crystals. The degradation is catalyzed by inorganic pyrophosphatases. If there is dysregulation of this homeostasis more PPi is produced, which ultimately contributes to the formation of the CPP crystals.

  3. Hydrothermal synthesis, structure and characterization of new NASICON related potassium iron (III) pyrophosphate

    Indian Academy of Sciences (India)

    G S Gopalakrishna; B H Doreswamy; M J Mahesh; M Mahendra; M A Sridhar; J Shashidhara Prasad; K G Ashamanjari

    2005-02-01

    A new potassium iron (III) pyrophosphate was synthesized by hydrothermal technique and characterized by X-ray studies. The compound crystallizes in a monoclinic space group, 21/, with cell parameters, = 7.365(2) Å, = 10.017(2) Å, = 8.214(1) Å, = 106.50(1)° and = 4. The structure has tunnel-type cavities and are congenial for ion transportation through them. The compound exhibits moderate thermal stability.

  4. Regularities of extracting humic acids from soils using sodium pyrophosphate solutions

    Science.gov (United States)

    Bakina, L. G.; Drichko, V. F.; Orlova, N. E.

    2017-02-01

    Regularities of extracting humic acids from different soil types (soddy-podzolic soil, gray forest soil, and all chernozem subtypes) with sodium pyrophosphate solutions at different pH values (from 5 to 13) have been studied. It is found that, regardless of soil type, the process occurs in two stages through the dissociation of carboxylic groups and phenolic hydroxyls, each of which can be described by a logistic function. Parameters of the logistic equations approximating the extraction of humic acids from soils at different pH values are independent of the content and composition of humus in soils. Changes in the optical density of humic acids extracted from soils using sodium pyrophosphate solutions with different pH values are described in the first approximation by the Gaussian function. The optically densest humic acids are extracted using sodium pyrophosphate solutions at pH 10. Therefore, it is proposed to use an extract with pH 10 for the characterization of organic matter with the maximum possible degree of humification in the given soil.

  5. Crystallization and preliminary X-ray diffraction study of phosphoribosyl pyrophosphate synthetase from E. Coli

    Energy Technology Data Exchange (ETDEWEB)

    Timofeev, V. I., E-mail: inna@ns.crys.ras.ru; Abramchik, Yu. A., E-mail: tostars@mail.ru; Zhukhlistova, N. E., E-mail: ugama@yandex.ru; Kuranova, I. P. [Russian Academy of Sciences, Shubnikov Institute of Crystallography (Russian Federation)

    2015-09-15

    Enzymes of the phosphoribosyl pyrophosphate synthetase family (PRPPS, EC 2.7.6.1) catalyze the formation of 5-phosphoribosyl pyrophosphate (5-PRPP) from adenosine triphosphate and ribose 5-phosphate. 5-Phosphoribosyl pyrophosphate is an important intermediate in the synthesis of purine, pyrimidine, and pyridine nucleotides, as well as of the amino acids histidine and tryptophan. The crystallization conditions for E. coli PRPPS were found by the vapor-diffusion technique and were optimized to apply the capillary counter-diffusion technique. The X-ray diffraction data set was collected from the crystals grown by the counter-diffusion technique using a synchrotron radiation source to 3.1-Å resolution. The crystals of PRPPS belong to sp. gr. P6{sub 3}22 and have the following unit-cell parameters: a = b = 104.44 Å, c = 124.98 Å, α = β = 90°, γ = 120°. The collected X-ray diffraction data set is suitable for the solution of the three-dimensional structure of PRPPS at 3.1-Å resolution.

  6. Crystallization and preliminary X-ray diffraction study of phosphoribosyl pyrophosphate synthetase from E. Coli

    Science.gov (United States)

    Timofeev, V. I.; Abramchik, Yu. A.; Zhukhlistova, N. E.; Kuranova, I. P.

    2015-09-01

    Enzymes of the phosphoribosyl pyrophosphate synthetase family (PRPPS, EC 2.7.6.1) catalyze the formation of 5-phosphoribosyl pyrophosphate (5-PRPP) from adenosine triphosphate and ribose 5-phosphate. 5-Phosphoribosyl pyrophosphate is an important intermediate in the synthesis of purine, pyrimidine, and pyridine nucleotides, as well as of the amino acids histidine and tryptophan. The crystallization conditions for E. coli PRPPS were found by the vapor-diffusion technique and were optimized to apply the capillary counter-diffusion technique. The X-ray diffraction data set was collected from the crystals grown by the counter-diffusion technique using a synchrotron radiation source to 3.1-Å resolution. The crystals of PRPPS belong to sp. gr. P6322 and have the following unit-cell parameters: a = b = 104.44 Å, c = 124.98 Å, α = β = 90°, γ = 120°. The collected X-ray diffraction data set is suitable for the solution of the three-dimensional structure of PRPPS at 3.1-Å resolution.

  7. Simple tools for assembling and searching high-density picolitre pyrophosphate sequence data

    Directory of Open Access Journals (Sweden)

    Parker Andrew G

    2008-04-01

    Full Text Available Abstract Background The advent of pyrophosphate sequencing makes large volumes of sequencing data available at a lower cost than previously possible. However, the short read lengths are difficult to assemble and the large dataset is difficult to handle. During the sequencing of a virus from the tsetse fly, Glossina pallidipes, we found the need for tools to search quickly a set of reads for near exact text matches. Methods A set of tools is provided to search a large data set of pyrophosphate sequence reads under a "live" CD version of Linux on a standard PC that can be used by anyone without prior knowledge of Linux and without having to install a Linux setup on the computer. The tools permit short lengths of de novo assembly, checking of existing assembled sequences, selection and display of reads from the data set and gathering counts of sequences in the reads. Results Demonstrations are given of the use of the tools to help with checking an assembly against the fragment data set; investigating homopolymer lengths, repeat regions and polymorphisms; and resolving inserted bases caused by incomplete chain extension. Conclusion The additional information contained in a pyrophosphate sequencing data set beyond a basic assembly is difficult to access due to a lack of tools. The set of simple tools presented here would allow anyone with basic computer skills and a standard PC to access this information.

  8. A sedge plant as the source of Kangaroo Island propolis rich in prenylated p-coumarate ester and stilbenes.

    Science.gov (United States)

    Duke, Colin C; Tran, Van H; Duke, Rujee K; Abu-Mellal, Abdallah; Plunkett, George T; King, Douglas I; Hamid, Kaiser; Wilson, Karen L; Barrett, Russell L; Bruhl, Jeremy J

    2017-02-01

    Propolis samples from Kangaroo Island, South Australia, were investigated for chemical constituents using high-field nuclear magnetic resonance spectral profiling. A type of propolis was found containing a high proportion of prenylated hydroxystilbenes. Subsequently, the botanical origin of this type of propolis was identified using a beehive propolis depletion method and analysis of flora. Ligurian honey bees, Apis mellifera ligustica Spinola, were found to produce propolis from resin exuded by the Australian native sedge plant Lepidosperma sp. Montebello (Cyperaceae). The plants, commonly known as sword sedge, were found to have resin that matched with the propolis samples identified as the most abundant propolis type on the island containing C- and O-prenylated tetrahydroxystilbenes (pTHOS) in addition to a small amount of prenylated p-coumarate. The isolation of five pTHOS not previously characterized are reported: (E)-4-(3-methyl-2-buten-1-yl)-3,4',5-trihydroxy-3'-methoxystilbene, (E)-2,4-bis(3-methyl-2-buten-1-yl)-3,3',4',5-tetrahydroxystilbene, (E)-2-(3-methyl-2-buten-1-yl)-3-(3-methyl-2-butenyloxy)-3',4',5-trihydroxystilbene, (E)-2,6-bis(3-methyl-2-buten-1-yl)-3,3',5,5'-tetrahydroxystilbene and (E)-2,6-bis(3-methyl-2-buten-1-yl)-3,4',5-trihydroxy-3'-methoxystilbene. A National Cancer Institute 60 human cell line anticancer screen of three of these compounds showed growth inhibitory activity. The large Australasian genus Lepidosperma is identified as a valuable resource for the isolation of substances with medicinal potential. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

  9. Prenylated Indolediketopiperazine Peroxides and Related Homologues from the Marine Sediment-Derived Fungus Penicillium brefeldianum SD-273

    Directory of Open Access Journals (Sweden)

    Chun-Yan An

    2014-01-01

    Full Text Available Three new indolediketopiperazine peroxides, namely, 24-hydroxyverruculogen (1, 26-hydroxyverruculogen (2, and 13-O-prenyl-26-hydroxyverruculogen (3, along with four known homologues (4–7, were isolated and identified from the culture extract of the marine sediment-derived fungus Penicillium brefeldianum SD-273. Their structures were determined based on the extensive spectroscopic analysis and compound 1 was confirmed by X-ray crystallographic analysis. The absolute configuration of compounds 1–3 was determined using chiral HPLC analysis of their acidic hydrolysates. Each of the isolated compounds was evaluated for antibacterial and cytotoxic activity as well as brine shrimp (Artemia salina lethality.

  10. Synthesis and evaluation of novel prenylated chalcone derivatives as anti-leishmanial and anti-trypanosomal compounds.

    Science.gov (United States)

    Passalacqua, Thais Gaban; Dutra, Luiz Antonio; de Almeida, Letícia; Velásquez, Angela Maria Arenas; Torres, Fabio Aurelio Esteves; Yamasaki, Paulo Renato; dos Santos, Mariana Bastos; Regasini, Luis Octavio; Michels, Paul A M; Bolzani, Vanderlan da Silva; Graminha, Marcia A S

    2015-08-15

    Chalcones form a class of compounds that belong to the flavonoid family and are widely distributed in plants. Their simple structure and the ease of preparation make chalcones attractive scaffolds for the synthesis of a large number of derivatives enabling the evaluation of the effects of different functional groups on biological activities. In this Letter, we report the successful synthesis of a series of novel prenylated chalcones via Claisen-Schmidt condensation and the evaluation of their effect on the viability of the Trypanosomatidae parasites Leishmania amazonensis, Leishmania infantum and Trypanosoma cruzi.

  11. Pyrophosphate-mediated iron acquisition from transferrin in Neisseria meningitidis does not require TonB activity.

    Science.gov (United States)

    Biville, Francis; Brézillon, Christophe; Giorgini, Dario; Taha, Muhamed-Kheir

    2014-01-01

    The ability to acquire iron from various sources has been demonstrated to be a major determinant in the pathogenesis of Neisseria meningitidis. Outside the cells, iron is bound to transferrin in serum, or to lactoferrin in mucosal secretions. Meningococci can extract iron from iron-loaded human transferrin by the TbpA/TbpB outer membrane complex. Moreover, N. meningitidis expresses the LbpA/LbpB outer membrane complex, which can extract iron from iron-loaded human lactoferrin. Iron transport through the outer membrane requires energy provided by the ExbB-ExbD-TonB complex. After transportation through the outer membrane, iron is bound by periplasmic protein FbpA and is addressed to the FbpBC inner membrane transporter. Iron-complexing compounds like citrate and pyrophosphate have been shown to support meningococcal growth ex vivo. The use of iron pyrophosphate as an iron source by N. meningitidis was previously described, but has not been investigated. Pyrophosphate was shown to participate in iron transfer from transferrin to ferritin. In this report, we investigated the use of ferric pyrophosphate as an iron source by N. meningitidis both ex vivo and in a mouse model. We showed that pyrophosphate was able to sustain N. meningitidis growth when desferal was used as an iron chelator. Addition of a pyrophosphate analogue to bacterial suspension at millimolar concentrations supported N. meningitidis survival in the mouse model. Finally, we show that pyrophosphate enabled TonB-independent ex vivo use of iron-loaded human or bovine transferrin as an iron source by N. meningitidis. Our data suggest that, in addition to acquiring iron through sophisticated systems, N. meningitidis is able to use simple strategies to acquire iron from a wide range of sources so as to sustain bacterial survival.

  12. Biosynthesis of monoterpenes. Stereochemistry of the enzymatic cyclizations of geranyl pyrophosphate to (+)-alpha-pinene and (-)-beta-pinene

    Energy Technology Data Exchange (ETDEWEB)

    Croteau, R.; Satterwhite, D.M.; Wheeler, C.J.; Felton, N.M.

    1989-02-05

    The conversion of geranyl pyrophosphate to (+)-alpha-pinene and to (-)-beta-pinene is considered to proceed by the initial isomerization of the substrate to (-)-(3R)- and to (+)-(3S)-linalyl pyrophosphate, respectively, and the subsequent cyclization of the anti, endo-conformer of these bound intermediates by mirror-image sequences which should result in the net retention of configuration at C1 of the geranyl precursor. Incubation of (1R)-(2-14C,1-3H)- and (1S)-(2-14C,1-3H)geranyl pyrophosphate with (+)-pinene cyclase and with (-)-pinene cyclase from common sage (Salvia officinalis) gave labeled (+)-alpha- and (-)-beta-pinene of unchanged 3H/14C ratio in all cases, and the (+)- and (-)-olefins were stereoselectively converted to (+)- and (-)-borneol, respectively, which were oxidized to the corresponding (+)- and (-)-isomers of camphor, again without change in isotope ratio. The location of the tritium was determined in each case by stereoselective, base-catalyzed exchange of the exo-alpha-hydrogens of these derived ketones. The results indicated that the configuration at C1 of the substrate was retained in the enzymatic transformations to the (+)- and (-)-pinenes, which is entirely consistent with the syn-isomerization of geranyl pyrophosphate to linalyl pyrophosphate, transoid to cisoid rotation, and anti, endo-cyclization of the latter. The absolute stereochemical elements of the antipodal reaction sequences were confirmed by the selective enzymatic conversions of (3R)- and (3S)-1Z-(1-3H)linalyl pyrophosphate to (+)-alpha-pinene and (-)-beta-pinene, respectively, and by the location of the tritium in the derived camphors as before. The summation of the results fully defines the overall stereochemistry of the coupled isomerization and cyclization of geranyl pyrophosphate to the antipodal pinenes.

  13. Pyrophosphate-mediated iron acquisition from transferrin in Neisseria meningitidis does not require TonB activity.

    Directory of Open Access Journals (Sweden)

    Francis Biville

    Full Text Available The ability to acquire iron from various sources has been demonstrated to be a major determinant in the pathogenesis of Neisseria meningitidis. Outside the cells, iron is bound to transferrin in serum, or to lactoferrin in mucosal secretions. Meningococci can extract iron from iron-loaded human transferrin by the TbpA/TbpB outer membrane complex. Moreover, N. meningitidis expresses the LbpA/LbpB outer membrane complex, which can extract iron from iron-loaded human lactoferrin. Iron transport through the outer membrane requires energy provided by the ExbB-ExbD-TonB complex. After transportation through the outer membrane, iron is bound by periplasmic protein FbpA and is addressed to the FbpBC inner membrane transporter. Iron-complexing compounds like citrate and pyrophosphate have been shown to support meningococcal growth ex vivo. The use of iron pyrophosphate as an iron source by N. meningitidis was previously described, but has not been investigated. Pyrophosphate was shown to participate in iron transfer from transferrin to ferritin. In this report, we investigated the use of ferric pyrophosphate as an iron source by N. meningitidis both ex vivo and in a mouse model. We showed that pyrophosphate was able to sustain N. meningitidis growth when desferal was used as an iron chelator. Addition of a pyrophosphate analogue to bacterial suspension at millimolar concentrations supported N. meningitidis survival in the mouse model. Finally, we show that pyrophosphate enabled TonB-independent ex vivo use of iron-loaded human or bovine transferrin as an iron source by N. meningitidis. Our data suggest that, in addition to acquiring iron through sophisticated systems, N. meningitidis is able to use simple strategies to acquire iron from a wide range of sources so as to sustain bacterial survival.

  14. Five new prenylated p-hydroxybenzoic acid derivatives with antimicrobial and molluscicidal activity from Piper aduncum leaves.

    Science.gov (United States)

    Orjala, J; Erdelmeier, C A; Wright, A D; Rali, T; Sticher, O

    1993-12-01

    Five new prenylated benzoic acid derivatives, methyl 3-(3,7-dimethyl-2,6-octadienyl)-4-methoxybenzoate (1), 1-(1-methylethyl)-4-methyl-3-cyclohexenyl 3,5-bis(3-methyl-2-butenyl)-4-hydroxybenzoate (2), 1-(1-methylethyl)-4-methyl-3-cyclohexenyl 3,5-bis(3-methyl-2-butenyl)-4-methoxybenzoate (3), methyl 3,5-bis(3-methyl-2-butenyl)-4-methoxybenzoate (4), and 4-hydroxy-3-(3-methyl-2-butenyl)-5-(3-methyl-2-butenyl)-benzoic acid (5) were isolated from the dried leaves of Piper aduncum L. (Piperaceae). Together with the new metabolites, four known prenylated benzoic acid derivatives, 3,5-bis(3-methyl-2-butenyl)-4-methoxybenzoic acid (6), 4-hydroxy-3,5-bis(3-methyl-2-butenyl)-benzoic acid (nervogenic acid, 7), methyl 4-hydroxy-3,5-bis(3-methyl-2-butenyl)-benzoate (8), and methyl 4-hydroxy-3-(3-methyl-2-butenyl)-benzoate (9) as well as, dillapiol (10), myristicin, and the three sesquiterpenes humulene, caryophyllene epoxide, and humulene epoxide were isolated. Compounds 7, 8, and 9 are reported as natural products for the first time. The structures of the isolates were elucidated by spectroscopic methods, mainly 1D-and 2D-NMR spectroscopy. Isolates 4-7, 9, and 10 were molluscicidal while 2, 5-7, and 9 displayed significant antibacterial activities.

  15. Prenylated Chalcone 2 Acts as an Antimitotic Agent and Enhances the Chemosensitivity of Tumor Cells to Paclitaxel

    Directory of Open Access Journals (Sweden)

    Joana Fonseca

    2016-07-01

    Full Text Available We previously reported that prenylated chalcone 2 (PC2, the O-prenyl derivative (2 of 2′-hydroxy-3,4,4′,5,6′-pentamethoxychalcone (1, induced cytotoxicity of tumor cells via disruption of p53-MDM2 interaction. However, the cellular changes through which PC2 exerts its cytotoxic activity and its antitumor potential, remain to be addressed. In the present work, we aimed to (i characterize the effect of PC2 on mitotic progression and the underlying mechanism; and to (ii explore this information to evaluate its ability to sensitize tumor cells to paclitaxel in a combination regimen. PC2 was able to arrest breast adenocarcinoma MCF-7 and non-small cell lung cancer NCI-H460 cells in mitosis. All mitosis-arrested cells showed collapsed mitotic spindles with randomly distributed chromosomes, and activated spindle assembly checkpoint. Live-cell imaging revealed that the compound induced a prolonged delay (up to 14 h in mitosis, culminating in massive cell death by blebbing. Importantly, PC2 in combination with paclitaxel enhanced the effect on cell growth inhibition as determined by cell viability and proliferation assays. Our findings demonstrate that the cytotoxicity induced by PC2 is mediated through antimitotic activity as a result of mitotic spindle damage. The enhancement effects of PC2 on chemosensitivity of cancer cells to paclitaxel encourage further validation of the clinical potential of this combination.

  16. Bioactivity of natural O-prenylated phenylpropenes from Illicium anisatum leaves and their derivatives against spider mites and fungal pathogens.

    Science.gov (United States)

    Koeduka, T; Sugimoto, K; Watanabe, B; Someya, N; Kawanishi, D; Gotoh, T; Ozawa, R; Takabayashi, J; Matsui, K; Hiratake, J

    2014-03-01

    A variety of volatile phenylpropenes, C6-C3 compounds are widely distributed in the plant kingdom, whereas prenylated phenylpropenes are limited to a few plant species. In this study, we analysed the volatile profiles from Illicium anisatum leaves and identified two O-prenylated phenylpropenes, 4-allyl-2-methoxy-1-[(3-methylbut-2-en-1-yl)oxy]benzene [O-dimethylallyleugenol (9)] and 5-allyl-1,3-dimethoxy-2-(3-methylbut-2-en-1-yl)oxy]benzene [O-dimethylallyl-6-methoxyeugenol (11)] as major constituents. The structure-activity relationship of a series of eugenol derivatives showed that specific phenylpropenes, including eugenol (1), isoeugenol (2) and 6-methoxyeugenol (6), with a phenolic hydroxy group had antifungal activity for a fungal pathogen, whereas guaiacol, a simple phenolic compound, and allylbenzene had no such activity. The eugenol derivatives that exhibited antifungal activity, in turn, had no significant toxicant property for mite oviposition. Interestingly, O-dimethylallyleugenol (9) in which the phenolic oxygen was masked with a dimethylallyl group exhibited a specific, potent oviposition deterrent activity for mites. The sharp contrast in structural requirements of phenylpropenes suggested distinct mechanisms underlying the two biological activities and the importance of a phenolic hydroxy group and its dimethylallylation for the structure-based design of new functional properties of phenylpropenes.

  17. Prenylated Chalcone 2 Acts as an Antimitotic Agent and Enhances the Chemosensitivity of Tumor Cells to Paclitaxel.

    Science.gov (United States)

    Fonseca, Joana; Marques, Sandra; Silva, Patrícia M A; Brandão, Pedro; Cidade, Honorina; Pinto, Madalena M; Bousbaa, Hassan

    2016-07-29

    We previously reported that prenylated chalcone 2 (PC2), the O-prenyl derivative (2) of 2'-hydroxy-3,4,4',5,6'-pentamethoxychalcone (1), induced cytotoxicity of tumor cells via disruption of p53-MDM2 interaction. However, the cellular changes through which PC2 exerts its cytotoxic activity and its antitumor potential, remain to be addressed. In the present work, we aimed to (i) characterize the effect of PC2 on mitotic progression and the underlying mechanism; and to (ii) explore this information to evaluate its ability to sensitize tumor cells to paclitaxel in a combination regimen. PC2 was able to arrest breast adenocarcinoma MCF-7 and non-small cell lung cancer NCI-H460 cells in mitosis. All mitosis-arrested cells showed collapsed mitotic spindles with randomly distributed chromosomes, and activated spindle assembly checkpoint. Live-cell imaging revealed that the compound induced a prolonged delay (up to 14 h) in mitosis, culminating in massive cell death by blebbing. Importantly, PC2 in combination with paclitaxel enhanced the effect on cell growth inhibition as determined by cell viability and proliferation assays. Our findings demonstrate that the cytotoxicity induced by PC2 is mediated through antimitotic activity as a result of mitotic spindle damage. The enhancement effects of PC2 on chemosensitivity of cancer cells to paclitaxel encourage further validation of the clinical potential of this combination.

  18. Synthesis and anti-cancer activity evaluation of novel prenylated and geranylated chalcone natural products and their analogs.

    Science.gov (United States)

    Wang, Hao-Meng; Zhang, Li; Liu, Jiang; Yang, Zhao-Liang; Zhao, Hong-Ye; Yang, Yao; Shen, Di; Lu, Kui; Fan, Zhen-Chuan; Yao, Qing-Wei; Zhang, Yong-Min; Teng, Yu-Ou; Peng, Yu

    2015-03-06

    Four natural chalcones bearing prenyl or geranyl groups, i.e., bavachalcone (1a), xanthoangelol (1b), isobavachalcone (1c), and isoxanthoangelol (1d) were synthesized by using a regio-selective iodination and the Suzuki coupling reaction as key steps. The first total synthesis of isoxanthoangelol (1d) was achieved in 36% overall yield. A series of diprenylated and digeranylated chalcone analogs were also synthesized by alkylation, regio-selective iodination, aldol condensation, Suzuki coupling and [1,3]-sigmatropic rearrangement. The structures of the 11 new derivatives were confirmed by (1)H NMR, (13)C NMR and HRMS. The anticancer activity of these new chalcone derivatives against human tumor cell line K562 were evaluated by MTT assay in vitro. SAR studies suggested that the 5'-prenylation/geranylation of the chalcones significantly enhance their cytotoxic activity. Among them, Bavachalcone (1a) displayed the most potent cytotoxic activity against K562 with IC50 value of 2.7 μM. The morphology changes and annexin-V/PI staining studies suggested that those chalcone derivatives inhibited the proliferation of K562 cells by inducing apoptosis.

  19. Influence of potassium pyrophosphate in electrolyte on coated layer of AZ91 Mg alloy formed by plasma electrolytic oxidation

    Institute of Scientific and Technical Information of China (English)

    Jin-Young CHO; Duck-Young HWANG; Dong-Heon LEE; Bongyoung YOO; Dong-Hyuk SHIN

    2009-01-01

    The effect of potassium pyrophosphate in the electrolyte on plasma electrolytic oxidation (PEO) process for AZ91 Mg alloy was investigated. The morphologies and chemical compositions of the coating layer on the AZ91 Mg alloy were evaluated and corrosion resistance was also estimated by potentiodynamic polarization analysis. The coating layer on AZ91 Mg alloy coated from the Bath 2 containing 0.03 mol/L of potassium pyrophosphate for 360 s exhibited considerably dense structure and contained 11%-18% (mass fraction) of phosphorous. The higher content of phosphorous of coating layer coated from Bath 2 could be detected at the bottom of oxide layer, which strongly implied that the phosphorous ion might be concentrated at the barrier layer. Corrosion potential of coating layer of AZ91 Mg alloy increased and corrosion current density decreased with increasing the concentration of potassium pyrophosphate. The polarization resistance (Rp) of coating layer of AZ91 Mg alloy coated from Bath 2 was 4.65×107 Ω/cm2, which was higher than that (Rp=3.56×104 Ω/cm2) of the sample coated from electrolyte without potassium pyrophosphate. The coating layer coated from Bath 2 containing 0.03 mol/L potassium pyrophosphate exhibited the best corrosion resistance.

  20. Neuroprotective effects of xanthohumol, a prenylated flavonoid from hops (Humulus lupulus), in ischemic stroke of rats.

    Science.gov (United States)

    Yen, Ting-Lin; Hsu, Chung-King; Lu, Wan-Jung; Hsieh, Cheng-Ying; Hsiao, George; Chou, Duen-Suey; Wu, Gong-Jhe; Sheu, Joen-Rong

    2012-02-29

    Xanthohumol is the principal prenylated flavonoid in hops (Humulus lupulus L.), an ingredient of beer. Xanthohumol was found to be a potent chemopreventive agent; however, no data are available concerning its neuroprotective effects. In the present study, the neuroprotective activity and mechanisms of xanthohumol in rats with middle cerebral artery occlusion (MCAO)-induced cerebral ischemia were examined. Treatment with xanthohumol (0.2 and 0.4 mg/kg; intraperitoneally) 10 min before MCAO dose-dependently attenuated focal cerebral ischemia and improved neurobehavioral deficits in cerebral ischemic rats. Xanthohumol treatment produced a marked reduction in infarct size compared to that in control rats. MCAO-induced focal cerebral ischemia was associated with increases in hypoxia-inducible factor (HIF)-1α, tumor necrosis factor (TNF)-α, inducible nitric oxide synthase (iNOS), and active caspase-3 protein expressions in ischemic regions. These expressions were obviously inhibited by treatment with xanthohumol. In addition, xanthohumol (3-70 μM) concentration-dependently inhibited platelet aggregation stimulated by collagen (1 μg/mL) in human platelet-rich plasma. An electron spin resonance (ESR) method was used to examine the scavenging activity of xanthohumol on free radicals which had formed. Xanthohumol (1.5 and 3 μM) markedly reduced the ESR signal intensity of hydroxyl radical (OH•) formation in the H₂O₂/NaOH/DMSO system. In conclusion, this study demonstrates for the first time that in addition to its originally being considered an agent preventing tumor growth, xanthohumol possesses potent neuroprotective activity. This activity is mediated, at least in part, by inhibition of inflammatory responses (i.e., HIF-1α, iNOS expression, and free radical formation), apoptosis (i.e., TNF-α, active caspase-3), and platelet activation, resulting in a reduction of infarct volume and improvement in neurobehavior in rats with cerebral ischemia. Therefore, this

  1. A role for prenylated rab acceptor 1 in vertebrate photoreceptor development

    Directory of Open Access Journals (Sweden)

    Dickison Virginia M

    2012-12-01

    Full Text Available Abstract Background The rd1 mouse retina is a well-studied model of retinal degeneration where rod photoreceptors undergo cell death beginning at postnatal day (P 10 until P21. This period coincides with photoreceptor terminal differentiation in a normal retina. We have used the rd1 retina as a model to investigate early molecular defects in developing rod photoreceptors prior to the onset of degeneration. Results Using a microarray approach, we performed gene profiling comparing rd1 and wild type (wt retinas at four time points starting at P2, prior to any obvious biochemical or morphological differences, and concluding at P8, prior to the initiation of cell death. Of the 143 identified differentially expressed genes, we focused on Rab acceptor 1 (Rabac1, which codes for the protein Prenylated rab acceptor 1 (PRA1 and plays an important role in vesicular trafficking. Quantitative RT-PCR analysis confirmed reduced expression of PRA1 in rd1 retina at all time points examined. Immunohistochemical observation showed that PRA1-like immunoreactivity (LIR co-localized with the cis-Golgi marker GM-130 in the photoreceptor as the Golgi translocated from the perikarya to the inner segment during photoreceptor differentiation in wt retinas. Diffuse PRA1-LIR, distinct from the Golgi marker, was seen in the distal inner segment of wt photoreceptors starting at P8. Both plexiform layers contained PRA1 positive punctae independent of GM-130 staining during postnatal development. In the inner retina, PRA1-LIR also colocalized with the Golgi marker in the perinuclear region of most cells. A similar pattern was seen in the rd1 mouse inner retina. However, punctate and significantly reduced PRA1-LIR was present throughout the developing rd1 inner segment, consistent with delayed photoreceptor development and abnormalities in Golgi sorting and vesicular trafficking. Conclusions We have identified genes that are differentially regulated in the rd1 retina at early

  2. Structural Basis for Gene Regulation by a Thiamine Pyrophosphate-Sensing Riboswitch

    Energy Technology Data Exchange (ETDEWEB)

    Serganov,A.; Polonskaia, A.; Phan, A.; Breaker, R.; Patel, D.

    2006-01-01

    Riboswitches are metabolite-sensing RNAs, typically located in the non-coding portions of messenger RNAs, that control the synthesis of metabolite-related proteins. Here we describe a 2.05 Angstroms crystal structure of a riboswitch domain from the Escherichia coli thiM mRNA4 that responds to the coenzyme thiamine pyrophosphate (TPP). TPP is an active form of vitamin B1, an essential participant in many protein-catalysed reactions. Organisms from all three domains of life including bacteria, plants and fungi, use TPP-sensing riboswitches to control genes responsible for importing or synthesizing thiamine and its phosphorylated derivatives, making this riboswitch class the most widely distributed member of the metabolite-sensing RNA regulatory system. The structure reveals a complex folded RNA in which one subdomain forms an intercalation pocket for the 4-amino-5-hydroxymethyl-2-methylpyrimidine moiety of TPP, whereas another subdomain forms a wider pocket that uses bivalent metal ions and water molecules to make bridging contacts to the pyrophosphate moiety of the ligand. The two pockets are positioned to function as a molecular measuring device that recognizes TPP in an extended conformation. The central thiazole moiety is not recognized by the RNA, which explains why the antimicrobial compound pyrithiamine pyrophosphate targets this riboswitch and downregulates the expression of thiamine metabolic genes. Both the natural ligand and its drug-like analogue stabilize secondary and tertiary structure elements that are harnessed by the riboswitch to modulate the synthesis of the proteins coded by the mRNA. In addition, this structure provides insight into how folded RNAs can form precision binding pockets that rival those formed by protein genetic factors.

  3. Diacylglycerol pyrophosphate binds and inhibits the glyceraldehyde-3-phosphate dehydrogenase in barley aleurone.

    Science.gov (United States)

    Astorquiza, Paula Luján; Usorach, Javier; Racagni, Graciela; Villasuso, Ana Laura

    2016-04-01

    The aleurona cell is a model that allows the study of the antagonistic effect of gibberellic acid (GA) and abscisic acid (ABA). Previous results of our laboratory demonstrated the involvement of phospholipids during the response to ABA and GA. ABA modulates the levels of diacylglycerol, phosphatidic acid and diacylglycerol pyrophosphate (DAG, PA, DGPP) through the activities of phosphatidate phosphatases, phospholipase D, diacylglycerol kinase and phosphatidate kinase (PAP, PLD, DGK and PAK). PA and DGPP are key phospholipids in the response to ABA, since both are capable of modifying the hydrolitic activity of the aleurona. Nevertheless, little is known about the mechanism of action of these phospholipids during the ABA signal. DGPP is an anionic phospholipid with a pyrophosphate group attached to diacylglycerol. The ionization of the pyrophosphate group may be important to allow electrostatic interactions between DGPP and proteins. To understand how DGPP mediates cell functions in barley aleurone, we used a DGPP affinity membrane assay to isolate DGPP-binding proteins from Hordeum vulgare, followed by mass spectrometric sequencing. A cytosolic glyceraldehyde-3-phosphate dehydrogenase (GAPDH, EC 1.2.1.12) was identified for being bound to DGPP. To validate our method, the relatively abundant GAPDH was characterized with respect to its lipid-binding properties, by fat western blot. GAPDH antibody interacts with proteins that only bind to DGPP and PA. We also observed that ABA treatment increased GAPDH abundance and enzyme activity. The presence of phospholipids during GAPDH reaction modulated the GAPDH activity in ABA treated aleurone. These data suggest that DGPP binds to GAPDH and this DGPP and GAPDH interaction provides new evidences in the study of DGPP-mediated ABA responses in barley aleurone.

  4. Cyclization of farnesyl pyrophosphate to the sesquiterpene olefins humulene and caryophyllene by an enzyme system from sage (Salvia officinalis)

    Energy Technology Data Exchange (ETDEWEB)

    Croteau, R.; Gundy, A.

    1984-09-01

    A soluble enzyme preparation obtained from sage (Salvia officinalis) leaves was shown to catalyze the divalent metal-ion dependent cyclization of trans, trans-farnesyl pyrophosphate to the macrocyclic sesquiterpene olefins humulene and caryophyllene. The identities of the biosynthetic products were confirmed by radiochromatographic analysis and by preparation of crystalline derivatives, and the specificity of labeling in the cyclization reaction was established by chemical degradation of the olefins derived enzymatically from (1-3H2)farnesyl pyrophosphate. These results constitute the first report on the cyclization of farnesyl pyrophosphate to humulene and caryophyllene, two of the most common sesquiterpenes in nature, and the first description of a soluble sesquiterpene cyclase to be isolated from leaves of a higher plant.

  5. N-glycosylation in the thermoacidophilic archaeon Sulfolobus acidocaldarius involves a short dolichol pyrophosphate carrier.

    Science.gov (United States)

    Guan, Ziqiang; Delago, Antonia; Nußbaum, Phillip; Meyer, Benjamin; Albers, Sonja-Verena; Eichler, Jerry

    2016-09-01

    N-glycosylation is a post-translational modification that occurs across evolution. In the thermoacidophilic archaea Sulfolobus acidocaldarius, glycoproteins are modified by an N-linked tribranched hexasaccharide reminiscent of the N-glycans assembled in Eukarya. Previously, hexose-bearing dolichol phosphate was detected in a S. acidocaldarius Bligh-Dyer lipid extract. Here, we used a specialized protocol for extracting lipid-linked oligosaccharides to detect a dolichol pyrophosphate bearing the intact hexasaccharide, as well as its biosynthetic intermediates. Furthermore, evidence for N-glycosylation of two S. acidocaldarius proteins by the same hexasaccharide and its derivatives was collected. These findings thus provide novel insight into archaeal N-glycosylation.

  6. Rapid efflux of Ca2+ from heart mitochondria in the presence of inorganic pyrophosphate.

    Science.gov (United States)

    Vercesi, A; Lehninger, A L

    1984-01-13

    Inorganic pyrophosphate (PPi) in the intracellular concentration range causes rapid efflux of Ca2+ from rat heart mitochondria oxidizing pyruvate + malate in a low Na+ medium. Half-maximal rates of Ca2+ efflux were given by 20 microM PPi. During and after PPi-stimulated Ca2+ efflux the mitochondria retain their structural integrity and complete respiratory control. Carboxyatractyloside inhibits PPi-stimulated Ca2+ efflux, indicating PPi must enter the matrix in order to promote Ca2+ efflux. Heart mitochondria have a much higher affinity for PPi uptake and PPi-induced Ca2+ efflux than liver mitochondria.

  7. Crystallization and preliminary X-ray crystallographic analysis of human geranylgeranyl pyrophosphate synthase

    Institute of Scientific and Technical Information of China (English)

    CHEN Yushu; LI Xiaofeng; LOU Zhiyong; WANG Weina; PANG Hai; RAO Zihe

    2006-01-01

    Human geranylgeranyl pyrophosphate synthase (GGPS) is an enzyme that catalyzes the synthesis of geranylgeranyl py rophosphate (GGPP) from farnesyldiphosphate and isopentenyldiphosphate. Recombinant human GGPS was crystallized by the hanging-drop vapor diffusion method. Crystals were grown at 18℃ using PEG 4000 as precipitant. Diffraction data were obtained to a resolution of 2.8 (A) from a single frozen crystal belonging to space group PI, with unit-cell parameters: α = 68.9 (A), b = 107.7 (A), c = 137.4 (A),α=99.6°, β=97.6°, γ=97.8°.

  8. Diagnosis and clinical manifestations of calcium pyrophosphate and basic calcium phosphate crystal deposition diseases.

    Science.gov (United States)

    Ea, Hang-Korng; Lioté, Frédéric

    2014-05-01

    Basic calcium phosphate and pyrophosphate calcium crystals are the 2 main calcium-containing crystals that can deposit in all skeletal tissues. These calcium crystals give rise to numerous manifestations, including acute inflammatory attacks that can mimic alarming and threatening differential diagnoses, osteoarthritis-like lesions, destructive arthropathies, and calcific tendinitis. Awareness of uncommon localizations and manifestations such as intraspinal deposition (eg, crowned dens syndrome, tendinitis of longus colli muscle, massive cervical myelopathy compression) prevents inappropriate procedures and cares. Coupling plain radiography, ultrasonography, computed tomography, and synovial fluid analysis allow accurate diagnosis by directly or indirectly identifying the GRAAL of microcrystal-related symptoms.

  9. The alteration of protein prenylation induces cardiomyocyte hypertrophy through Rheb-mTORC1 signalling and leads to chronic heart failure.

    Science.gov (United States)

    Xu, Na; Guan, Shan; Chen, Zhong; Yu, Yang; Xie, Jun; Pan, Fei-Yan; Zhao, Ning-Wei; Liu, Li; Yang, Zhong-Zhou; Gao, Xiang; Xu, Biao; Li, Chao-Jun

    2015-04-01

    G protein-regulated cell function is crucial for cardiomyocytes, and any deregulation of its gene expression or protein modification can lead to pathological cardiac hypertrophy. Herein, we report that protein prenylation, a lipidic modification of G proteins that facilitates their association with the cell membrane, might control the process of cardiomyocyte hypertrophy. We found that geranylgeranyl diphosphate synthase (GGPPS), a key enzyme involved in protein prenylation, played a critical role in postnatal heart growth by regulating cardiomyocyte size. Cardiac-specific knockout of GGPPS in mice led to spontaneous cardiac hypertrophy, beginning from week 4, accompanied by the persistent enlargement of cardiomyocytes. This hypertrophic effect occurred by altered prenylation of G proteins. Evaluation of the prenylation, membrane association and hydrophobicity showed that Rheb was hyperactivated and increased mTORC1 signalling pathway after GGPPS deletion. Protein farnesylation or mTORC1 inhibition blocked GGPPS knockdown-induced mTORC1 activation and suppressed the larger neonatal rat ventricle myocyte size and cardiomyocyte hypertrophy in vivo, demonstrating a central role of the FPP-Rheb-mTORC1 axis for GGPPS deficiency-induced cardiomyocyte hypertrophy. The sustained cardiomyocyte hypertrophy progressively provoked cardiac decompensation and dysfunction, ultimately causing heart failure and adult death. Importantly, GGPPS was down-regulated in the hypertrophic hearts of mice subjected to transverse aortic constriction (TAC) and in failing human hearts. Moreover, HPLC-MS/MS detection revealed that the myocardial farnesyl diphosphate (FPP):geranylgeranyl diphosphate (GGPP) ratio was enhanced after pressure overload. Our observations conclude that the alteration of protein prenylation promotes cardiomyocyte hypertrophic growth, which acts as a potential cause for pathogenesis of heart failure and may provide a new molecular target for hypertrophic heart disease

  10. Prognostic implications of acute myocardial infarct scintigraphy with /sup 99m/Tc-pyrophosphate

    Energy Technology Data Exchange (ETDEWEB)

    Holman, B.L.; Chisholm, R.J.; Braunwald, E.

    1978-02-01

    The predictive value of myocardial scintigraphy with /sup 99m/Tc-pyrophosphate was studied in 100 patients admitted to the coronary care unit with suspected acute myocardial infarction. None of the 21 patients with normal scintigrams had acute myocardial infarction by other criteria. Fifty-five percent of patients with diffuse uptake (pattern B), 73% of patients with focal uptake (pattern C) and all patients with intense focal uptake (pattern D) and massive uptake (pattern E) had acute infarction. The complication rate in the hospital and after discharge (mean followup: 6.1 months) for patients with pattern E was 88% compared to 42% for D, 30% for C, 36% for B and 10% for patients with normal scintigrams (A). For patients with acute infarction with patterns C, D, and E, the complication rate rose with increasing size of the myocardial uptake of /sup 99m/Tc-pyrophosphate. In addition to its diagnostic potential, scintigraphy provides prognostic information which is useful for patient triage and for therapeutic decisions early in the evolution of the infarct.

  11. Comparison of pyrophosphate and gluconate scan of dog hearts with experimental cardiomyopathy

    Energy Technology Data Exchange (ETDEWEB)

    Duska, F.; Novak, J.; Kafka, P.; Kubicek, J.; Vizda, J.; Mazurova, Y.; Veverkova, O. (Karlova Univ., Hradec Kralove (Czechoslovakia). Lekarska Fakulta)

    1983-04-01

    High intravenous doses of theophylline with adrenalin were used to produce experimental cardiomyopathy in dogs. This damage was visualized scintigraphically using either sup(99m)Tc-pyrophosphate (10 dogs) or sup(99m)Tc-gluconate (another 10 dogs). Scintigraphic examinations using sup(99m)Tc-pyrophosphate were carried out 48 hours after the damage had developed: in two dogs the examination was negative, in two cases boundary, in 6 cases the scintigraphic finding was clearly positive. sup(99m)Tc-gluconate was used in the examination of 5 animals four hours after the damage had developed. In this case the scan was significantly positive in all cases. The gluconate scan was made 24 hours after damage, again in 5 dogs. Here the positive change was less explicit, in one case the finding was negative. Histological examination of the affected myocardium showed in all cases a very light damage, in many instances on the limit of resolution by light microscopy. The findings were always of degenerative (dystrophic) changes and microcirculation disorders without any necrosis. The work showed that both studied radiopharmaceutical preparations are a very sensitive but nonspecific indicator of non-ischemic disorders of the myocardium. For sup(99m)Tc-gluconate this is an original finding.

  12. cDNA cloning, chromosome mapping and expression characterization of human geranylgeranyl pyrophosphate synthase

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Geranylgeranyl pyrophosphate (GGPP) mainly participates in post-translational modification for various proteins including Rho/Rac, Rap and Rab families, as well as in regulation for cell apoptosis. Geranylgeranyl pyrophosphate synthase (GGPPS), which catalyzes the condensation reaction between farnesyl diphosphate and isopentenyl diphosphate, is the key enzyme for synthesizing GGPP. We report the isolation of a gene transcript showing high homology with Drosophila GGPPS cDNA. The transcript is 1 466 bp in length and contains an intact open reading frame (ORF) ranging from nt 239 to 1 138. This ORF encodes a deduced protein of 300 residues with calculated molecular weight of 35 ku. The deduced protein shows 57.5% identity and 75% similarity with Drosophila GGPPS, and contains five characteristic domains of prenyltransferases. Northern hybridization revealed that human GGPPS was expressed highest in heart, and moderately in spleen, testis, brain, placenta, lung, liver, skeletal muscle, kidney and pancreas. No obvious bands were detected in other examined tissues. The GGPPS gene was located on human chromosome 1q43 by Radiation Hybrid mapping method. It was proved that there was a putative predisposing gene for prostate cancer in this region, and that analogs of GGPP can inhibit the geranylgeranylation of p21rap protein in PC-3 prostate cancer cell lines. These facts suggest that GGPPS may be one of the candidate genes for prostate cancer.

  13. Thiamine pyrophosphate riboswitch in some representative plant species: a bioinformatics study.

    Science.gov (United States)

    Yadav, Sunita; Swati, D; Chandrasekharan, Hariharan

    2015-01-01

    Metabolites regulate their own production by directly interacting with highly conserved regions of mRNA that are capable of forming discrete tertiary structures. Such regions of mRNA are called riboswitches. The thiamine pyrophosphate (TPP) riboswitch is the most common riboswitch in different organisms. The TPP is an essential coenzyme that is synthesized by the coupling of pyrimidine (hydroxymethyl pyrimidine) and thiazole (hydroxyethyl thiazole). The TPP riboswitch was searched across all possible phyla of plant kingdom by using Arabidopsis thaliana, a model organism in which TPP riboswitch is already found. The aptameric domain of the TPP riboswitch is conserved at the sequence as well as structure levels in all chosen plant species. The sequence of the noncoding RNA that acts as a riboswitch and is folded into an appropriate stem-loop hairpin secondary structure with minimum free energy is predicted by several computational tools. Most of the secondary structures are similar but not the same, because of variation in sequence size. The TPP ligand can bind to the 3' untranslated region of the aptameric sequence, between the loops P2, P4, and P5 and the region between J2/3 and J4/5. The sequence of these loop regions in all predicted tertiary structure of the riboswitch in representative plant species--green algae to flowering plants--is the same, and the residues situated in these junctions are directly involved in binding thymine pyrophosphate and are conserved in all the representative species.

  14. Cloning and characterization of farnesyl pyrophosphate synthase from the highly branched isoprenoid producing diatom Rhizosolenia setigera.

    Science.gov (United States)

    Ferriols, Victor Marco Emmanuel N; Yaginuma, Ryoko; Adachi, Masao; Takada, Kentaro; Matsunaga, Shigeki; Okada, Shigeru

    2015-05-21

    The diatom Rhizosolenia setigera Brightwell produces highly branched isoprenoid (HBI) hydrocarbons that are ubiquitously present in marine environments. The hydrocarbon composition of R. setigera varies between C25 and C30 HBIs depending on the life cycle stage with regard to auxosporulation. To better understand how these hydrocarbons are biosynthesized, we characterized the farnesyl pyrophosphate (FPP) synthase (FPPS) enzyme of R. setigera. An isolated 1465-bp cDNA clone contained an open reading frame spanning 1299-bp encoding a protein with 432 amino acid residues. Expression of the RsFPPS cDNA coding region in Escherichia coli produced a protein that exhibited FPPS activity in vitro. A reduction in HBI content from diatoms treated with an FPPS inhibitor, risedronate, suggested that RsFPPS supplies precursors for HBI biosynthesis. Product analysis by gas chromatography-mass spectrometry also revealed that RsFPPS produced small amounts of the cis-isomers of geranyl pyrophosphate and FPP, candidate precursors for the cis-isomers of HBIs previously characterized. Furthermore, RsFPPS gene expression at various life stages of R. setigera in relation to auxosporulation were also analyzed. Herein, we present data on the possible role of RsFPPS in HBI biosynthesis, and it is to our knowledge the first instance that an FPPS was cloned and characterized from a diatom.

  15. Nuclear receptor engineering based on novel structure activity relationships revealed by farnesyl pyrophosphate.

    Science.gov (United States)

    Goyanka, Ritu; Das, Sharmistha; Samuels, Herbert H; Cardozo, Timothy

    2010-11-01

    Nuclear receptors (NRs) comprise the second largest protein family targeted by currently available drugs, acting via specific ligand interactions within the ligand binding domain (LBD). Recently, farnesyl pyrophosphate (FPP) was shown to be a unique promiscuous NR ligand, activating a subset of NR family members and inhibiting wound healing in skin. The current study aimed at visualizing the unique basis of FPP interaction with multiple receptors in order to identify general structure-activity relationships that operate across the NR family. Docking of FPP to the 3D structures of the LBDs of a diverse set of NRs consistently revealed an electrostatic FPP pyrophosphate contact with an NR arginine conserved in the NR family, a hydrophobic farnesyl contact with NR helix-12 and a ligand binding pocket volume between 300 and 430 Å(3) as the minimal requirements for FPP activation of any NR. Lack of any of these structural features appears to render a given NR resistant to FPP activation. We used these structure-activity relationships to rationally design and successfully engineer several mutant human estrogen receptors that retain responsiveness to estradiol but no longer respond to FPP.

  16. Impaired mechanical response of an EDMD mutation leads to motility phenotypes that are repaired by loss of prenylation.

    Science.gov (United States)

    Zuela, Noam; Zwerger, Monika; Levin, Tal; Medalia, Ohad; Gruenbaum, Yosef

    2016-05-01

    There are roughly 14 distinct heritable autosomal dominant diseases associated with mutations in lamins A/C, including Emery-Dreifuss muscular dystrophy (EDMD). The mechanical model proposes that the lamin mutations change the mechanical properties of muscle nuclei, leading to cell death and tissue deterioration. Here, we developed an experimental protocol that analyzes the effect of disease-linked lamin mutations on the response of nuclei to mechanical strain in living Caenorhabditis elegans We found that the EDMD mutation L535P disrupts the nuclear mechanical response specifically in muscle nuclei. Inhibiting lamin prenylation rescued the mechanical response of the EDMD nuclei, reversed the muscle phenotypes and led to normal motility. The LINC complex and emerin were also required to regulate the mechanical response of C. elegans nuclei. This study provides evidence to support the mechanical model and offers a potential future therapeutic approach towards curing EDMD.

  17. Xanthohumol, a prenylated chalcone derived from hops, inhibits proliferation, migration and interleukin-8 expression of hepatocellular carcinoma cells.

    Science.gov (United States)

    Dorn, Christoph; Weiss, Thomas S; Heilmann, Jörg; Hellerbrand, Claus

    2010-02-01

    Xanthohumol, the major prenylated chalcone found in hops, is well known to exert anti-cancer effects, but information regarding the impact on hepatocellular carcinoma (HCC) cells and potential adverse effects on non-tumorous hepatocytes is limited. Here, we show that xanthohumol at a concentration of 25 microM induced apoptosis in two HCC cell lines (HepG2 and Huh7). Furthermore, xanthohumol repressed proliferation and migration, as well as TNF induced NF-kappaB activity and interleukin-8 expression in both cell lines at even lower concentrations. In contrast, xanthohumol concentrations up to 100 microM did not affect viability of primary human hepatocytes in vitro. In summary, our data showed that xanthohumol can ameliorate different pro-tumorigenic mechanisms known to promote HCC progression, indicating its potential as promising therapeutic agent that selectively affects cancer cells.

  18. The inhibitory effects of xanthohumol, a prenylated chalcone derived from hops, on cell growth and tumorigenesis in human pancreatic cancer.

    Science.gov (United States)

    Jiang, Weiliang; Zhao, Senlin; Xu, Ling; Lu, Yingying; Lu, Zhanjun; Chen, Congying; Ni, Jianbo; Wan, Rong; Yang, Lijuan

    2015-07-01

    Pancreatic cancer (PC) is one of the most lethal human malignancies worldwide. Here, we demonstrated that xanthohumol (XN), the most abundant prenylated chalcone isolated from hops, inhibited the growth of cultured PC cells and their subcutaneous xenograft tumors. XN treatment was found to induce cell cycle arrest and apoptosis of PC cells (PANC-1, BxPC-3) by inhibiting phosphorylation of signal transducer and activator of transcription 3 (STAT3) and expression of its downstream targeted genes cyclinD1, survivin, and Bcl-xL at the messenger RNA level, which involved in regulation of apoptosis and the cell cycle. Overall, our results suggested that XN presents a promising candidate therapeutic agent against human PC and the STAT3 signaling pathway is its key molecular target.

  19. Prenylated flavone from roots of a hybrid between Artocarpus heterophyllus and Artocarpus integer and its biological activities

    Energy Technology Data Exchange (ETDEWEB)

    Panthong, Kanda, E-mail: kanda.p@psu.ac.th [Prince of Songkla University (Thailand). Natural Product Research Center of Excellence; Tohdee, Kanogwan [Prince of Songkla University (Thailand). Faculty of Science. Department of Chemistry; Hutadilok-Towatana, Nongporn [Prince of Songkla University (Thailand). Dept. of Biochemistry; Voravuthikunchai, Supayang P. [Prince of Songkla University (Thailand). Faculty of Science. Department of Microbiology; Chusri, Sasitorn [Prince of Songkla University (Thailand). Faculty of Traditional Thai Medicine

    2013-10-15

    One new prenylated flavone, 2,8-dihydroxy-3,10-dimethoxy-6-(2-methyl-1-propen-1-yl)- 6H,7H-[1]benzopyrano[4,3-b][1]-benzopyran-7-one, together with 24 known compounds were isolated from crude acetone extract from the roots of a hybrid between Artocarpus heterophyllus and Artocarpus integer. Their structures were determined by 1D and 2D nuclear magnetic resonance (NMR) spectroscopic data. The antioxidant and antibacterial activities of the isolated compounds were evaluated. The new compound showed potent antioxidant activity against DPPH Bullet and superoxide with IC{sub 50} values of 0.033 and 0.125 mg mL{sup -1}, respectively. Significant antibacterial activity against Acinetobacter baumannii was observed with MIC value of 50 {mu}g mL{sup -1}. (author)

  20. Prenylated indole diketopiperazine alkaloids from a mangrove rhizosphere soil derived fungus Aspergillus effuses H1-1.

    Science.gov (United States)

    Gao, Huquan; Zhu, Tianjiao; Li, Dehai; Gu, Qianqun; Liu, Weizhong

    2013-08-01

    One new prenylated indole diketopiperazine alkaloid, named dihydroneochinulin B (1), one known spiro-polyketide-diketopiperazine hybrid cryptoechinuline D (2) and three related known metabolites didehydroechinulin B (3), neoechinulin B (4) and auroglaucin (5) were isolated from the mangrove rhizosphere soil derived fungus, Aspergillus effuses H1-1. The structures were assigned by detailed spectroscopic analysis. The enantiomers of cryptoechinuline D (2) were separated to be (+)-cryptoechinuline D (2a) and (-)-cryptoechinuline D (2b) by chiral HPLC, and their absolute configurations were determined by ECD analysis. The cytotoxic effects of the compounds were preliminarily evaluated on P388, HL-60, BEL-7402 and A-549 cell lines by SRB or MTT methods, and compounds 2, 2a and 3 showed significant activities.

  1. Identification of prenyl ethyl ether as a source of metallic, solvent-like off-flavor in hazelnut.

    Science.gov (United States)

    Amrein, Thomas M; Schwager, Hugo; Meier, Roberto; Frey, Peter; Gassenmeier, Klaus F

    2010-11-10

    In a large batch of ground hazelnuts, a metallic, solvent-like off-note was detected. In this investigation, the volatiles from the batch showing off-notes were compared to a batch without off-notes. On the basis of gas chromatography (GC) sniffing and instrumental analysis, a terpenoid compound, prenyl ethyl ether, was identified as a key contributor to the off-note. The compound was quantified, and its contribution to the metallic, solvent-like off-flavor was confirmed by spiking experiments and sensory evaluation. Analytical and sensory experiments found that the off-note was still present in hazelnut cakes. Fat oxidation did not contribute to the off-flavor. Analysis of market products demonstrated the correlation between the identified terpenoid and the off-flavor. It is assumed that fungi are involved in off-flavor formation.

  2. Coordination ligand exchange of a xanthene probe-Ce(III) complex for selective fluorescence sensing of inorganic pyrophosphate.

    Science.gov (United States)

    Kittiloespaisan, Ekkachai; Takashima, Ippei; Kiatpathomchai, Wansika; Wongkongkatep, Jirarut; Ojida, Akio

    2014-02-28

    A fluorescence sensing system for inorganic pyrophosphate based on ligand exchange of the Ce(III) complex of a xanthene-type probe is developed. This sensing system is successfully applied to the fluorescence detection of polymerase-catalyzed DNA amplification using loop-mediated isothermal amplification.

  3. Spin canting in an unprecedented three-dimensional pyrophosphate- and 2,2'-bipyrimidine-bridged cobalt(II) framework.

    Science.gov (United States)

    Marino, Nadia; Mastropietro, Teresa F; Armentano, Donatella; De Munno, Giovanni; Doyle, Robert P; Lloret, Francesc; Julve, Miguel

    2008-10-14

    The three-dimensional cobalt(ii) compound of formula {[Co(2)(P(2)O(7))(bpym)(2)].12H(2)O}(n), where the pyrophosphate and 2,2'-bipyrimidine act as bridging ligands, is a new example of a spin-canted antiferromagnet with T(c) = 19 K.

  4. Inhibitors of protein:farnesyl transferase and protein:geranylgeranyl transferase I : Synthesis of homologous diphosphonate analogs of isoprenylated pyrophosphate

    NARCIS (Netherlands)

    Overhand, M.; Stuivenberg, H.R.; Pieterman, E.; Cohen, L.H.; Leeuwen, R.E.W. van; Valentijn, A.R.P.M.; Overkleeft, H.S.; Marel, G.A. van der; Boom, J.H. van

    1998-01-01

    Novel diphosphonate homologs 7a-7c, and their cyclic counterparts 8a- 8c, of the previously synthesized farnesyl pyrophosphate analogs 1 and 2 were prepared and tested for their inhibition potency and specificity of the enzymes PFT and PGGT-I. Compound 2 was shown to be the most potent inhibitor of

  5. Human genome-wide RNAi screen identifies an essential role for inositol pyrophosphates in Type-I interferon response.

    Directory of Open Access Journals (Sweden)

    Niyas Kudukkil Pulloor

    2014-02-01

    Full Text Available The pattern recognition receptor RIG-I is critical for Type-I interferon production. However, the global regulation of RIG-I signaling is only partially understood. Using a human genome-wide RNAi-screen, we identified 226 novel regulatory proteins of RIG-I mediated interferon-β production. Furthermore, the screen identified a metabolic pathway that synthesizes the inositol pyrophosphate 1-IP7 as a previously unrecognized positive regulator of interferon production. Detailed genetic and biochemical experiments demonstrated that the kinase activities of IPPK, PPIP5K1 and PPIP5K2 (which convert IP5 to1-IP7 were critical for both interferon induction, and the control of cellular infection by Sendai and influenza A viruses. Conversely, ectopically expressed inositol pyrophosphate-hydrolases DIPPs attenuated interferon transcription. Mechanistic experiments in intact cells revealed that the expression of IPPK, PPIP5K1 and PPIP5K2 was needed for the phosphorylation and activation of IRF3, a transcription factor for interferon. The addition of purified individual inositol pyrophosphates to a cell free reconstituted RIG-I signaling assay further identified 1-IP7 as an essential component required for IRF3 activation. The inositol pyrophosphate may act by β-phosphoryl transfer, since its action was not recapitulated by a synthetic phosphonoacetate analogue of 1-IP7. This study thus identified several novel regulators of RIG-I, and a new role for inositol pyrophosphates in augmenting innate immune responses to viral infection that may have therapeutic applications.

  6. Genome-based characterization of two prenylation steps in the assembly of the stephacidin and notoamide anticancer agents in a marine-derived Aspergillus sp.

    Science.gov (United States)

    Ding, Yousong; de Wet, Jeffrey R; Cavalcoli, James; Li, Shengying; Greshock, Thomas J; Miller, Kenneth A; Finefield, Jennifer M; Sunderhaus, James D; McAfoos, Timothy J; Tsukamoto, Sachiko; Williams, Robert M; Sherman, David H

    2010-09-15

    Stephacidin and notoamide natural products belong to a group of prenylated indole alkaloids containing a core bicyclo[2.2.2]diazaoctane ring system. These bioactive fungal secondary metabolites have a range of unusual structural and stereochemical features but their biosynthesis has remained uncharacterized. Herein, we report the first biosynthetic gene cluster for this class of fungal alkaloids based on whole genome sequencing of a marine-derived Aspergillus sp. Two central pathway enzymes catalyzing both normal and reverse prenyltransfer reactions were characterized in detail. Our results establish the early steps for creation of the prenylated indole alkaloid structure and suggest a scheme for the biosynthesis of stephacidin and notoamide metabolites. The work provides the first genetic and biochemical insights for understanding the structural diversity of this important family of fungal alkaloids.

  7. Molecular Cloning and Characterisation of Farnesyl Pyrophosphate Synthase from Tripterygium wilfordii.

    Science.gov (United States)

    Zhao, Yu-Jun; Chen, Xin; Zhang, Meng; Su, Ping; Liu, Yu-Jia; Tong, Yu-Ru; Wang, Xiu-Juan; Huang, Lu-Qi; Gao, Wei

    2015-01-01

    Farnesylpyrophosphate synthase (FPS) catalyzes the biosynthesis of farnesyl pyrophosphate (FPP), which is an important precursor of sesquiterpenoids such as artemisinin and wilfordine. In the present study, we report the molecular cloning and characterization of two full-length cDNAs encoding FPSs from Tripterygium wilfordii (TwFPSs). TwFPSs maintained their capability to synthesise FPP in vitro when purified as recombinant proteins from E. coli. Consistent with the endogenous role of FPS in FPP biosynthesis, TwFPSs were highly expressed in T. wilfordii roots, and were up-regulated upon methyl jasmonate (MeJA) treatment. The global gene expression profiles suggested that the TwFPSs might play an important regulatory role interpenoid biosynthesis in T. wilfordii, laying the groundwork for the future study of the synthetic biology of natural terpene products.

  8. Eu(2+) luminescence in SrCaP2 O7 pyrophosphate phosphor.

    Science.gov (United States)

    Kohale, R L; Dhoble, S J

    2013-01-01

    A series of Eu(2+) activated SrCaP2 O7 pyrophosphate phosphors were synthesized by the modified solid-state reaction method. The X-ray diffraction (XRD) and photoluminescence (PL) properties of these phosphors were investigated at room temperature. The excitation spectra indicate that these phosphors can be effectively excited by Hg-free excitation. The emission spectra exhibit strong blue performance, which is due to the 4f(6) 5d(1) →4f(7) transition of Eu(2+) . The Fourier transform infrared spectrum at room temperature was investigated and surface morphology has been studied by scanning electron microscope. The prepared phosphor exhibited intense blue emission at the 427 nm owing to Eu(2+) ion by Hg-free excitation at 330 nm, that is, solid-state lighting excitation. Hence, the availability of such a phosphor will significantly help in the growth of blue-emitting solid-state lighting applications.

  9. Synthesis and Biodegradation of St-g-poly(MMA-co-VAc) Initiated by Manganic Pyrophosphate

    Institute of Scientific and Technical Information of China (English)

    ZHU Lin-hui; CHEN Mi-feng; JI Yan; XIA Hai-ping; DING Ma-tai

    2004-01-01

    Methyl methacrylate (MMA) and vinyl acetate (VAc) were grafted onto corn starch with manganic pyrophosphate { [Mn(H2P2O7)3]3-} as the initiator and water as the reaction medium. The influences of reaction conditions, including pH value, initiator concentration, monomer concentration and its composition, on percent grafting and grafting efficiency were investigated. The graft copolymer was characterized by means of IR spectroscopy, scanning electron micrograph(SEM) and 1H NMR spectroscopy. The biodegradation experiment showed that the degradation of corn starch-g-poly(MMA-co-VAc) was mainly from starch. However,after poly VAc in the side chain was transformed into poly vinyl alcohol(PVA), both starch and the grafted side chain could be degraded completely.

  10. Pyrophosphate synthesis in iron mineral films and membranes simulating prebiotic submarine hydrothermal precipitates

    Science.gov (United States)

    Barge, Laura M.; Doloboff, Ivria J.; Russell, Michael J.; VanderVelde, David; White, Lauren M.; Stucky, Galen D.; Baum, Marc M.; Zeytounian, John; Kidd, Richard; Kanik, Isik

    2014-03-01

    Cells use three main ways of generating energy currency to drive metabolism: (i) conversion of adenosine diphosphate (ADP) to adenosine triphosphate (ATP) by the proton motive force through the rotor-stator ATP synthase; (ii) the synthesis of inorganic phosphate˜phosphate bonds via proton (or sodium) pyrophosphate synthase; or (iii) substrate-level phosphorylation through the direct donation from an active phosphoryl donor. A mechanism to produce a pyrophosphate bond as “energy currency” in prebiotic systems is one of the most important considerations for origin of life research. Baltscheffsky (1996) suggests that inorganic pyrophosphate (PO74-; PPi) may have preceded ATP/ADP as an energy storage molecule in earliest life, produced by an H+ pyrophosphatase. Here we test the hypothesis that PPi could be synthesized in inorganic precipitates simulating hydrothermal chimney structures transected by thermal and/or ionic gradients. Appreciable yields of PPi were obtained via substrate phosphorylation by acetyl phosphate within the iron sulfide/silicate precipitates at temperatures expected for an alkaline hydrothermal system. The formation of PPi only occurred in the solid phase, i.e. when both Pi and the phosphoryl donor were precipitated with Fe-sulfides or Fe-silicates. The amount of Ac-Pi incorporated into the precipitate was a significant factor in the amount of PPi that could form, and phosphate species were more effectively incorporated into the precipitate at higher temperatures (⩾50 to >85 °C). Thus, we expect that the hydrothermal precipitate would be more enriched in phosphate (and especially, Ac-Pi) near the inner margins of a hydrothermal mound where PPi formation would be at a maximum. Iron sulfide and iron silicate precipitates effectively stabilized Ac-Pi and PPi against hydrolysis (relative to hydrolysis in aqueous solution). Thus it is plausible that PPi could accumulate as an energy currency up to useful concentrations for early life in a

  11. Fast determination of bioactive phytic acid and pyrophosphate in walnuts using microwave accelerated extraction.

    Science.gov (United States)

    Liu, Tong; He, Liu; Valiente, Manuel; López-Mesas, Montserrat

    2017-04-15

    Bioactive compounds phytic acid (IP6) and pyrophosphate (PPi) are minor components of walnuts with the ability of being inhibitors of urolithiasis, among others. Since simultaneous analysis of IP6 and PPi have known drawbacks, a new method to determine their content in walnuts has been developed with emphasis on their extraction from walnuts by microwave-assisted extraction (MAE). Acid content of extracting solvent, extraction time and temperature were optimized. After extraction, compounds were purified by selective adsorption/desorption on an anion exchange solid phase extraction and analyzed by inductive coupled plasma/mass spectrometry. A mixture of H2SO4 and HCl as solvent to extract both, IP6 and PPi, provided results slightly higher than those determined by conventional extraction with no statistical difference. The possible hydrolysis of phytic acid by MAE was analyzed. Compared with the conventional acid extraction method, significant improvement is achieved by the MAE method reducing extraction time from 3h to 10min.

  12. New lithium iron pyrophosphate as 3.5 V class cathode material for lithium ion battery.

    Science.gov (United States)

    Nishimura, Shin-ichi; Nakamura, Megumi; Natsui, Ryuichi; Yamada, Atsuo

    2010-10-01

    A new pyrophosphate compound Li(2)FeP(2)O(7) was synthesized by a conventional solid-state reaction, and its crystal structure was determined. Its reversible electrode operation at ca. 3.5 V vs Li was identified with the capacity of a one-electron theoretical value of 110 mAh g(-1) even for ca. 1 μm particles without any special efforts such as nanosizing or carbon coating. Li(2)FeP(2)O(7) and its derivatives should provide a new platform for related lithium battery electrode research and could be potential competitors to commercial olivine LiFePO(4), which has been recognized as the most promising positive cathode for a lithium-ion battery system for large-scale applications, such as plug-in hybrid electric vehicles.

  13. Lentiviral-Mediated Silencing of Farnesyl Pyrophosphate Synthase through RNA Interference in Mice

    Directory of Open Access Journals (Sweden)

    Jian Yang

    2015-01-01

    Full Text Available Farnesyl pyrophosphate synthase (FPPS plays a vital role in the mevalonate pathway and has been shown to be involved in hypertrophy and cardiovascular diseases. Lentivirus-mediated RNA interference (RNAi to knock down a gene of interest has become a promising new tool for the establishment of transgenic animals. The interfering fragment, named pLVT202, was chosen from cardiomyocytes tested in vitro and was microinjected into the perivitelline space of zygotes from C57BL/6J mice via a lentivirus vehicle; 20 were identified as carrying copies of the transgene using the polymerase chain reaction (PCR. Real-time PCR and western blotting analysis showed that FPPS was downregulated in multiple tissues in the transgenic mice. The transgenic mouse model provides a novel means of studying the gene function of FPPS.

  14. Phebaclavin I, a novel 3-prenylated coumarin, and trichoclin acetate, a new natural furocoumarin, from the aerial parts of Phebalium aff. tuberculosum (Rutaceae).

    Science.gov (United States)

    Roux, Delphine; Muyard, Frédéric; Girard, Corinne; Colombain, Michel; Tillequin, François; Waterman, Peter G; Bévalot, Françoise

    2006-03-01

    Phebaclavin I, a novel 3-prenylated coumarin, was isolated from the aerial parts of Phebalium aff. tuberculosum (Rutaceae) together with five known related compounds, Phebaclavin A, B, D, G, H. The structure of phebaclavin I was established by spectroscopic methods. Several other known coumarins were obtained, including trichoclin acetate, a furocoumarin isolated for the first time from a natural source, but previously described from acetylation of trichoclin.

  15. Genome-based Characterization of Two Prenylation Steps in the Assembly of the Stephacidin and Notoamide Anticancer Agents in a Marine-derived Aspergillus sp

    OpenAIRE

    Ding, Yousong; de Wet, Jeffrey R.; Cavalcoli, James; Li, Shengying; Greshock, Thomas J.; Miller, Kenneth A.; Finefield, Jennifer M.; Sunderhaus, James D.; McAfoos, Timothy; Tsukamoto, Sachiko; Williams, Robert M.; Sherman, David H.

    2010-01-01

    Stephacidin and notoamide natural products belong to a group of prenylated indole alkaloids containing a core bicyclo[2.2.2]diazaoctane ring system. These bioactive fungal secondary metabolites have a range of unusual structural and stereochemical features but their biosynthesis has remained uncharacterized. Herein, we report the first biosynthetic gene cluster for this class of fungal alkaloids based on whole genome sequencing of a marine-derived Aspergillus sp. Two central pathway enzymes c...

  16. Fungal Inositol Pyrophosphate IP7 Is Crucial for Metabolic Adaptation to the Host Environment and Pathogenicity

    Science.gov (United States)

    Lev, Sophie; Li, Cecilia; Desmarini, Desmarini; Saiardi, Adolfo; Fewings, Nicole L.; Schibeci, Stephen D.; Sharma, Raghwa; Sorrell, Tania C.

    2015-01-01

    ABSTRACT Inositol pyrophosphates (PP-IPs) comprising inositol, phosphate, and pyrophosphate (PP) are essential for multiple functions in eukaryotes. Their role in fungal pathogens has never been addressed. Cryptococcus neoformans is a model pathogenic fungus causing life-threatening meningoencephalitis. We investigate the cryptococcal kinases responsible for the production of PP-IPs (IP7/IP8) and the hierarchy of PP-IP importance in pathogenicity. Using gene deletion and inositol polyphosphate profiling, we identified Kcs1 as the major IP6 kinase (producing IP7) and Asp1 as an IP7 kinase (producing IP8). We show that Kcs1-derived IP7 is the most crucial PP-IP for cryptococcal drug susceptibility and the production of virulence determinants. In particular, Kcs1 kinase activity is essential for cryptococcal infection of mouse lungs, as reduced fungal burdens were observed in the absence of Kcs1 or when Kcs1 was catalytically inactive. Transcriptome and carbon source utilization analysis suggested that compromised growth of the KCS1 deletion strain (Δkcs1 mutant) in the low-glucose environment of the host lung is due to its inability to utilize alternative carbon sources. Despite this metabolic defect, the Δkcs1 mutant established persistent, low-level asymptomatic pulmonary infection but failed to elicit a strong immune response in vivo and in vitro and was not readily phagocytosed by primary or immortalized monocytes. Reduced recognition of the Δkcs1 cells by monocytes correlated with reduced exposure of mannoproteins on the Δkcs1 mutant cell surface. We conclude that IP7 is essential for fungal metabolic adaptation to the host environment, immune recognition, and pathogenicity. PMID:26037119

  17. Biochemical and Histological Effects of Thiamine Pyrophosphate against Acetaminophen-Induced Hepatotoxicity.

    Science.gov (United States)

    Uysal, Hilal Bektas; Dağlı, Bekir; Yılmaz, Mustafa; Kahyaoğlu, Fadime; Gökçimen, Alparslan; Ömürlü, İmran Kurt; Demirci, Buket

    2016-01-01

    The aim of this study was to investigate whether thiamine pyrophosphate (TPP) has biochemical and histological preventive effects on oxidative liver damage induced by paracetamol (APAP). Rats were divided into the following groups: healthy control (HG), APAP (AG, 1500 mg/kg, orally), thiamine pyrophosphate (TPPG, 100 mg/kg, intraperitoneally), APAP+NAC (ANAC, 100 mg/kg, intraperitoneally), APAP+TPP (ATPG) and APAP+NAC+TPP (ANTG). Oxidant, antioxidant parameters, liver function tests and histological assessment were performed between groups. Malondialdehyde levels in the AG, HG, TPPG, ANAC, ATPG and ANTG groups were 0.470 ± 0.210, 0.213 ± 0.004, 0.194 ± 0.001, 0.197 ± 0.06, 0.199 ± 0.008 and 0.173 ± 0.010 μmol/g protein, respectively. Total glutathione levels were 7.787 ± 0.395, 14.925 ± 0.932, 13.200 ± 0.984, 13.162 ± 0.486, 13.287 ± 0.787 and 13.500 ± 0.891 μm/g protein, respectively. In the AG group, marked liver damage occurred with the elevation of liver function tests and oxidative stress markers, such as malondialdehyde, myeloperoxidase and nitric oxide (p Biochemical results were congruent with the histological changes of oxidative damage. Compared to the AG group (p 0.05) among the ANAC, ANTG and ATPG groups in terms of oxidant/antioxidant levels. TPP proved to be as efficacious as standard therapy and may be beneficial in APAP-induced hepatotoxicity.

  18. Direct observation of multiple tautomers of oxythiamine and their recognition by the thiamine pyrophosphate riboswitch.

    Science.gov (United States)

    Singh, Vipender; Peng, Chunte Sam; Li, Deyu; Mitra, Koyel; Silvestre, Katherine J; Tokmakoff, Andrei; Essigmann, John M

    2014-01-17

    Structural diversification of canonical nucleic acid bases and nucleotide analogues by tautomerism has been proposed to be a powerful on/off switching mechanism allowing regulation of many biological processes mediated by RNA enzymes and aptamers. Despite the suspected biological importance of tautomerism, attempts to observe minor tautomeric forms in nucleic acid or hybrid nucleic acid-ligand complexes have met with challenges due to the lack of sensitive methods. Here, a combination of spectroscopic, biochemical, and computational tools probed tautomerism in the context of an RNA aptamer-ligand complex; studies involved a model ligand, oxythiamine pyrophosphate (OxyTPP), bound to the thiamine pyrophosphate (TPP) riboswitch (an RNA aptamer) as well as its unbound nonphosphorylated form, oxythiamine (OxyT). OxyTPP, similarly to canonical heteroaromatic nucleic acid bases, has a pyrimidine ring that forms hydrogen bonding interactions with the riboswitch. Tautomerism was established using two-dimensional infrared (2D IR) spectroscopy, variable temperature FTIR and NMR spectroscopies, binding isotope effects (BIEs), and computational methods. All three possible tautomers of OxyT, including the minor enol tautomer, were directly identified, and their distributions were quantitated. In the bound form, BIE data suggested that OxyTPP existed as a 4'-keto tautomer that was likely protonated at the N1'-position. These results also provide a mechanistic framework for understanding the activation of riboswitch in response to deamination of the active form of vitamin B1 (or TPP). The combination of methods reported here revealing the fine details of tautomerism can be applied to other systems where the importance of tautomerism is suspected.

  19. Chronic calcium pyrophosphate crystal inflammatory arthritis induced by extreme hypomagnesemia in short bowel syndrome

    Directory of Open Access Journals (Sweden)

    Hahn Markus

    2012-09-01

    Full Text Available Abstract Background Short bowel syndrome (SBS may induce a plethora of clinical symptoms ranging from underweight to nutrient-, vitamin- and electrolyte deficiencies. The objective of this case report is to illustrate how demanding the management of a 60 year old patient with SBS and recurrent joint attacks was for different medical disciplines. Case presentation The patient with SBS presented with a body mass index of 16.5 kg/m2 after partial jejunoileal resection of the small intestine with a six year long history of recurrent pain attacks in multiple peripheral joints, chronic diarrhoea and food intolerances. Pain attacks occurred 4–5 times a week with a median consumption of 15 mg prednisone per day. The interdisciplinary workup after several gastroenterologic, rheumatologic, radiologic, psychiatric and orthopedic consultations is shown including successful treatment steps. Clinical diagnosis revealed no systemic inflammatory disease, but confirmed extreme hypomagnesemia (0.2 mmol/l after reproducible pathological magnesium resorption tests as causative for chronic calcium pyrophosphate crystal inflammatory arthritis (pseudogout, chondrocalcinosis. Multidisciplinary treatment included application of colchicines, parenteral nutrition and magnesium substitution, antiperistaltic agents and avoidance of intolerant foods. Normalization of magnesium levels and a marked remission of joint attacks were achieved after six months with significant reduction of prednisone to 1.5 mg/day. Conclusion Despite the rarity of this condition, it is important to know that hypomagnesaemia may be associated with calcium pyrophosphate crystal inflammatory arthritis (chondrocalcinosis and that SBS patients may be prone to develop extreme hypomagnesaemia causing recurrent joint attacks without systemic inflammation.

  20. Thermodynamic, dynamic and solvational properties of PDEδ binding to farnesylated cystein: a model study for uncovering the molecular mechanism of PDEδ interaction with prenylated proteins.

    Science.gov (United States)

    Suladze, S; Ismail, S; Winter, R

    2014-01-30

    The protein PDEδ is an important solubilizing factor for several prenylated proteins including the Ras subfamily members. The binding occurs mainly through the farnesyl anchor of Ras proteins, which is recognized by a hydrophobic pocket of PDEδ. In this study, we carried out a detailed study of the thermodynamic and solvational properties of PDEδ binding to farnesyl-cystein, which serves as a model for PDEδ association to prenylated proteins. Using various biophysical approaches in conjunction with theoretical considerations, we show here that binding of the largely hydrophobic ligand surprisingly has enthalpy-driven signature, and the entropy change is largely controlled by the fine balance between the hydrational and conformational terms. Moreover, binding of PDEδ to farnesyl-cystein is accompanied by an increase in thermal stability, the release of about 150 water molecules from the interacting species, a decrease in solvent accessible surface area, and a marked decrease of the volume fluctuations and hence dynamics of the protein. Altogether, our results shed more light on the molecular mechanism of PDEδ interaction with prenylated Ras proteins, which is also prerequisite for an optimization of the structure-based molecular design of drugs against Ras related diseases and for understanding the multitude of biological functions of PDEδ.

  1. Competitive coordination of Cu2+ between cysteine and pyrophosphate ion: toward sensitive and selective sensing of pyrophosphate ion in synovial fluid of arthritis patients.

    Science.gov (United States)

    Deng, Jingjing; Yu, Ping; Yang, Lifen; Mao, Lanqun

    2013-02-19

    Direct selective and sensitive sensing of pyrophosphate ion (PPi) in synovial fluid of arthritis patients is of great importance because of its crucial roles in the diagnosis and therapy of arthritic diseases. In this study, we demonstrate a sensitive and selective method for PPi sensing in synovial fluid of arthritis patients with gold nanoparticles (Au-NPs) as the signal readout based on the competitive coordination chemistry of Cu(2+) between cysteine and PPi. Initially, Au-NPs stabilized with cysteine are red in color and exhibit absorption at 519 nm in the UV-vis spectrum. The addition of an aqueous solution of Cu(2+) to the Au-NPs dispersion containing cysteine causes the aggregation of Au-NPs, resulting in the wine red-to-blue color change and the appearance of a new absorption at 650 nm in the UV-vis spectrum of the Au-NPs dispersion. The subsequent addition of PPi to the Au-NPs aggregation well solubilizes the aggregated Au-NPs with the changes in both the color and the UV-vis spectrum of the Au-NPs dispersion. These changes are ascribed to the higher coordination reactivity between Cu(2+) and PPi than that between Cu(2+) and cysteine. On the basis of this, the concentration of PPi can be visualized with the naked eyes through the blue-to-wine red color change of the Au-NPs dispersion and quantitatively determined by UV-vis spectroscopy. Under the optimized conditions, the ratio of the absorbance at 650 nm (A(650)) to that at 519 nm (A(519)) shows a linear relationship with PPi concentration within a concentration range from 130 nM to 1.3 mM. The method demonstrated here is highly sensitive, free from the interference from other species in the synovial fluid, and is thus particularly useful for fast and simple clinic diagnosis of arthritic diseases.

  2. AntigenMap 3D: an online antigenic cartography resource.

    Science.gov (United States)

    Barnett, J Lamar; Yang, Jialiang; Cai, Zhipeng; Zhang, Tong; Wan, Xiu-Feng

    2012-05-01

    Antigenic cartography is a useful technique to visualize and minimize errors in immunological data by projecting antigens to 2D or 3D cartography. However, a 2D cartography may not be sufficient to capture the antigenic relationship from high-dimensional immunological data. AntigenMap 3D presents an online, interactive, and robust 3D antigenic cartography construction and visualization resource. AntigenMap 3D can be applied to identify antigenic variants and vaccine strain candidates for pathogens with rapid antigenic variations, such as influenza A virus. http://sysbio.cvm.msstate.edu/AntigenMap3D

  3. Prenylation of a Rab1B mutant with altered GTPase activity is impaired in cell-free systems but not in intact mammalian cells.

    Science.gov (United States)

    Wilson, A L; Sheridan, K M; Erdman, R A; Maltese, W A

    1996-09-15

    Previous studies have reached differing conclusions as to whether or not guanine-nucleotide-dependent conformational changes affect the ability of Rab proteins to undergo post-translational modification by Rab:geranylgeranyltransferase (Rab-GGTase). We now show that the ability of a Rab1B mutant [Q67L (Gln-67-->Leu)] with reduced intrinsic GTPase activity to undergo geranylgeranylation in cell-free assays depends on the guanine nucleotide composition of the system. When GTP is the predominant nucleotide in the assay, Rab1BQ67L is a poor substrate. However, when GDP is present and GTP is omitted, prenylation of the Q67L mutant is comparable with that of the wild-type (WT) protein. These studies, coupled with the poor prenylation of Rab1BWT in the presence of the non-hydrolysable GTP analogue guanosine 5'-[gamma-thio]triphosphate, support the notion that Rab-GGTase prefers substrates in the GDP conformation. When the abilities of Rab1BQ67L and Rab1BWT to undergo prenylation were compared by metabolic labelling of transiently expressed proteins in cultured human 293 cells, we did not observe a decline in prenylation of the mutant protein as predicted on the basis of the cell-free assays. Moreover, the Q67L mutant was comparable with the wild-type Rab1B in its ability to associate with co-expressed Rab GDP dissociation inhibitors in 293 cells. These findings raise the possibility that unidentified proteins present in intact cells may compensate for the reduced intrinsic GTPase activity of the Q67L mutant, allowing a significant proportion of the nascent Rab1BQ67L to assume a GDP conformation. The differential prenylation of Rab1BQ67L in cell-free systems versus intact cells underscores the importance of evaluating the post-translational modification of specific Rab mutants in vivo, where poorly characterized regulatory proteins may have a significant effect on GTPase activity or nucleotide exchange rates.

  4. A Novel Inositol Pyrophosphate Phosphatase in Saccharomyces cerevisiae: Siw14 PROTEIN SELECTIVELY CLEAVES THE β-PHOSPHATE FROM 5-DIPHOSPHOINOSITOL PENTAKISPHOSPHATE (5PP-IP5).

    Science.gov (United States)

    Steidle, Elizabeth A; Chong, Lucy S; Wu, Mingxuan; Crooke, Elliott; Fiedler, Dorothea; Resnick, Adam C; Rolfes, Ronda J

    2016-03-25

    Inositol pyrophosphates are high energy signaling molecules involved in cellular processes, such as energetic metabolism, telomere maintenance, stress responses, and vesicle trafficking, and can mediate protein phosphorylation. Although the inositol kinases underlying inositol pyrophosphate biosynthesis are well characterized, the phosphatases that selectively regulate their cellular pools are not fully described. The diphosphoinositol phosphate phosphohydrolase enzymes of the Nudix protein family have been demonstrated to dephosphorylate inositol pyrophosphates; however, theSaccharomyces cerevisiaehomolog Ddp1 prefers inorganic polyphosphate over inositol pyrophosphates. We identified a novel phosphatase of the recently discovered atypical dual specificity phosphatase family as a physiological inositol pyrophosphate phosphatase. Purified recombinant Siw14 hydrolyzes the β-phosphate from 5-diphosphoinositol pentakisphosphate (5PP-IP5or IP7)in vitro. In vivo,siw14Δ yeast mutants possess increased IP7levels, whereas heterologousSIW14overexpression eliminates IP7from cells. IP7levels increased proportionately whensiw14Δ was combined withddp1Δ orvip1Δ, indicating independent activity by the enzymes encoded by these genes. We conclude that Siw14 is a physiological phosphatase that modulates inositol pyrophosphate metabolism by dephosphorylating the IP7isoform 5PP-IP5to IP6.

  5. An investigation of the effect of thiamine pyrophosphate on cisplatin-induced oxidative stress and DNA damage in rat brain tissue compared with thiamine: thiamine and thiamine pyrophosphate effects on cisplatin neurotoxicity.

    Science.gov (United States)

    Turan, M I; Cayir, A; Cetin, N; Suleyman, H; Siltelioglu Turan, I; Tan, H

    2014-01-01

    This study investigated the effects of thiamine pyrophosphate (TPP) at dosages of 10 and 20 mg/kg on oxidative stress induced in rat brain tissue with cisplatin and compared this with thiamine. Cisplatin neurotoxicity represents one of the main restrictions on the drug being given in effective doses. Oxidative stress is considered responsible for cisplatin toxicity. Our results showed that cisplatin increased the levels of oxidant parameters such as lipid peroxidation (thio barbituric acid reactive substance (TBARS)) and myeloperoxidase (MPO) in brain tissue and suppressed the effects of antioxidants such as total glutathione (GSH) and superoxide dismutase (SOD). TPP, especially at a dosage of 20 mg/kg, significantly reduced TBARS and MPO levels that increase with cisplatin administration compared with the thiamine group, while TPP significantly increases GSH and SOD levels. In addition, the level of 8-Gua (guanine), a product of DNA damage, was 1.7 ± 0.12 8-hydroxyl guanine (8-OH Gua)/105 Gua in brain tissue in the control group receiving cisplatin, compared with 0.97 ± 0.03 8-OH Gua/105 Gua in the thiamine pyrophosphate (20 mg/kg) group and 1.55 ± 0.11 8-OH Gua/105 Gua in the thiamine (20 mg/kg) group. These results show that thiamine pyrophosphate significantly prevents oxidative damage induced by cisplatin in brain tissue, while the protective effect of thiamine is insignificant.

  6. Scintigraphic myocardial imaging with sup(99m)Tc-labelled pyrophosphate of experimentally produced cardiomyopathy in dogs

    Energy Technology Data Exchange (ETDEWEB)

    Duska, F.; Novak, J.; Vizda, J.; Kubicek, J.; Kafka, P.; Mazurova, Y.; Bradna, P.

    1981-12-01

    Scintigraphic examination of the myocardium using sup(99m)Tc-labelled pyrophosphate was carried out in 10 dogs with experimentally produced cardiomyopathy. This was brought by introvenous administration of high doses of adrenalin and theophylline. The scan was positive in 8 out of 10 dogs. Hot foci were very extensive. The degree of accumulation was however low (2+). Histological examination of the myocardium using the light microscope showed only scarcely distinguishable damage to the tissue without the presence of necrosis. ECG examinations were normal in all cases. By means of sup(99m)Tc-labelled pyrophosphate even very small myocardial disorders can thus be detected. This fact may be of clinical importance for an early diagnosis of heart lesions.

  7. Three-dimensional structure of phosphoribosyl pyrophosphate synthetase from E. coli at 2.71 Å resolution

    Energy Technology Data Exchange (ETDEWEB)

    Timofeev, V. I., E-mail: inna@ns.crys.ras.ru, E-mail: tostars@mail.ru, E-mail: ugama@yandex.ru [Russian Academy of Sciences, Shubnikov Institute of Crystallography (Russian Federation); Abramchik, Yu. A. [Russian Academy of Sciences, Shemyakin–Ovchinnikov Institute of Bioorganic Chemistry (Russian Federation); Zhukhlistova, N. E. [Russian Academy of Sciences, Shubnikov Institute of Crystallography (Russian Federation); Muravieva, T. I.; Esipov, R. S. [Russian Academy of Sciences, Shemyakin–Ovchinnikov Institute of Bioorganic Chemistry (Russian Federation); Kuranova, I. P. [Russian Academy of Sciences, Shubnikov Institute of Crystallography (Russian Federation)

    2016-01-15

    Phosphoribosyl pyrophosphate synthetase from Escherichia coli was cloned, purified, and crystallized. Single crystals of the enzyme were grown under microgravity. The X-ray diffraction data set was collected at the Spring-8 synchrotron facility and used to determine the three-dimensional structure of the enzyme by the molecular-replacement method at 2.71 Å resolution. The active and regulatory sites in the molecule of E. coli phosphoribosyl pyrophosphate synthetase were revealed by comparison with the homologous protein from Bacillus subtilis, the structure of which was determined in a complex with functional ligands. The conformations of polypeptide-chain fragments surrounding and composing the active and regulatory sites were shown to be identical in both proteins.

  8. Three-dimensional structure of phosphoribosyl pyrophosphate synthetase from E. coli at 2.71 Å resolution

    Science.gov (United States)

    Timofeev, V. I.; Abramchik, Yu. A.; Zhukhlistova, N. E.; Muravieva, T. I.; Esipov, R. S.; Kuranova, I. P.

    2016-01-01

    Phosphoribosyl pyrophosphate synthetase from Escherichia coli was cloned, purified, and crystallized. Single crystals of the enzyme were grown under microgravity. The X-ray diffraction data set was collected at the Spring-8 synchrotron facility and used to determine the three-dimensional structure of the enzyme by the molecular-replacement method at 2.71 Å resolution. The active and regulatory sites in the molecule of E. coli phosphoribosyl pyrophosphate synthetase were revealed by comparison with the homologous protein from Bacillus subtilis, the structure of which was determined in a complex with functional ligands. The conformations of polypeptide-chain fragments surrounding and composing the active and regulatory sites were shown to be identical in both proteins.

  9. Use of cyclodextrins in biotransformation reactions with cell cultures of Morus nigra: biosynthesis of prenylated chalcone isocordoin.

    Science.gov (United States)

    Bolasco, Adriana; Fioravanti, Rossella; Rossi, Francesca; Rossi, Paola; Vitali, Alberto

    2010-06-16

    In vivo biotransformation experiments were performed by using a cell suspension culture of Morus nigra expressing a high PT (prenyltransferase) activity, fed with the target substrate 2',4'-dihydroxychalcone. In order to improve the reaction yields by enhancing the chalcone solubility, three different cyclodextrins have been used to host the substrate. The respective complexes have been studied by means of both spectroscopic and calorimetric techniques (Fourier-transform infrared, 1H-NMR and differential scanning calorimetry) and the solution behaviours have been characterized by solubility phase studies. The hydroxypropyl-beta-cyclodextrin complex was found to be the most suitable for biotransformation, and the reaction of prenylation resulted in a 6-fold higher yield of the final product when compared with the use of the free substrate. The reaction provided as the sole product the 3'-dimethylallyl derivative isocordoin, a biologically active plant compound. The results obtained allow the development of systems based on the use of biofermentors or the use of immobilized cells in order to enhance the biotransformation yields.

  10. Enzymatic prenylation and oxime ligation for the synthesis of stable and homogeneous protein-drug conjugates for targeted therapy.

    Science.gov (United States)

    Lee, Joong-Jae; Choi, Hyo-Jung; Yun, Misun; Kang, YingJin; Jung, Ji-Eun; Ryu, Yiseul; Kim, Tae Yoon; Cha, Young-Je; Cho, Hyun-Soo; Min, Jung-Joon; Chung, Chul-Woong; Kim, Hak-Sung

    2015-10-05

    Targeted therapy based on protein-drug conjugates has attracted significant attention owing to its high efficacy and low side effects. However, efficient and stable drug conjugation to a protein binder remains a challenge. Herein, a chemoenzymatic method to generate highly stable and homogenous drug conjugates with high efficiency is presented. The approach comprises the insertion of the CaaX sequence at the C-terminal end of the protein binder, prenylation using farnesyltransferase, and drug conjugation through an oxime ligation reaction. MMAF and an EGFR-specific repebody are used as the antitumor agent and protein binder, respectively. The method enables the precisely controlled synthesis of repebody-drug conjugates with high yield and homogeneity. The utility of this approach is illustrated by the notable stability of the repebody-drug conjugates in human plasma, negligible off-target effects, and a remarkable antitumor activity in vivo. The present method can be widely used for generating highly homogeneous and stable PDCs for targeted therapy.

  11. The molecular organization of prenylated flavonoid xanthohumol in DPPC multibilayers: X-ray diffraction and FTIR spectroscopic studies.

    Science.gov (United States)

    Arczewska, Marta; Kamiński, Daniel M; Górecka, Ewa; Pociecha, Damian; Rój, Edward; Sławińska-Brych, Adrianna; Gagoś, Mariusz

    2013-02-01

    Xanthohumol (XN) is the major prenylated flavonoid found in hop resin. It has attracted considerable attention in recent years due to its wide spectrum of biological activities and the beneficial effect on human health. Since lipid membrane is first target for biologically active compounds, we decided to investigate the influence of XN on the dipalmitoylphosphatidylcholine (DPPC) multibilayers. Interactions of XN with DPPC were investigated as a function of temperature and its concentration by using X-ray diffraction and the ATR-FTIR spectroscopy techniques. The aim of understanding the mechanisms of molecular interactions between XN and DPPC was to indicate the localization of the XN with respect to the membrane and the type of interaction with phospholipids. The results revealed that XN changes the physical properties of the DPPC multibilayers in the form of dry film. A new complex formation between XN and DPPC is reported. The detailed analysis of refraction effect indicates the changes in electron density ratio between hydrophobic and hydrophilic zones of lipid at phase transition. This is in compliance with reported changes in FTIR spectra where at pretransition XN moves from interface region between polar heads to the neighborhood of phosphate groups.

  12. Xanthohumol, a Prenylated Chalcone from Hops, Inhibits the Viability and Stemness of Doxorubicin-Resistant MCF-7/ADR Cells

    Directory of Open Access Journals (Sweden)

    Ming Liu

    2016-12-01

    Full Text Available Xanthohumol is a unique prenylated flavonoid in hops (Humulus lupulus L. and beer. Xanthohumol has been shown to possess a variety of pharmacological activities. There is little research on its effect on doxorubicin-resistant breast cancer cells (MCF-7/ADR and the cancer stem-like cells exiting in this cell line. In the present study, we investigate the effect of xanthohumol on the viability and stemness of MCF-7/ADR cells. Xanthohumol inhibits viability, induces apoptosis, and arrests the cell cycle of MCF-7/ADR cells in a dose-dependent manner; in addition, xanthohumol sensitizes the inhibition effect of doxorubicin on MCF-7/ADR cells. Interestingly, we also find that xanthohumol can reduce the stemness of MCF-7/ADR cells evidenced by the xanthohumol-induced decrease in the colony formation, the migration, the percentage of side population cells, the sphere formation, and the down-regulation of stemness-related biomarkers. These results demonstrate that xanthohumol is a promising compound targeting the doxorubicin resistant breast cancer cells and regulating their stemness, which, therefore, will be applied as a potential candidate for the development of a doxorubicin-resistant breast cancer agent and combination therapy of breast cancer.

  13. Xanthohumol, a Prenylated Chalcone from Hops, Inhibits the Viability and Stemness of Doxorubicin-Resistant MCF-7/ADR Cells.

    Science.gov (United States)

    Liu, Ming; Yin, Hua; Qian, Xiaokun; Dong, Jianjun; Qian, Zhonghua; Miao, Jinlai

    2016-12-28

    Xanthohumol is a unique prenylated flavonoid in hops (Humulus lupulus L.) and beer. Xanthohumol has been shown to possess a variety of pharmacological activities. There is little research on its effect on doxorubicin-resistant breast cancer cells (MCF-7/ADR) and the cancer stem-like cells exiting in this cell line. In the present study, we investigate the effect of xanthohumol on the viability and stemness of MCF-7/ADR cells. Xanthohumol inhibits viability, induces apoptosis, and arrests the cell cycle of MCF-7/ADR cells in a dose-dependent manner; in addition, xanthohumol sensitizes the inhibition effect of doxorubicin on MCF-7/ADR cells. Interestingly, we also find that xanthohumol can reduce the stemness of MCF-7/ADR cells evidenced by the xanthohumol-induced decrease in the colony formation, the migration, the percentage of side population cells, the sphere formation, and the down-regulation of stemness-related biomarkers. These results demonstrate that xanthohumol is a promising compound targeting the doxorubicin resistant breast cancer cells and regulating their stemness, which, therefore, will be applied as a potential candidate for the development of a doxorubicin-resistant breast cancer agent and combination therapy of breast cancer.

  14. GGPPS, a new EGR-1 target gene, reactivates ERK 1/2 signaling through increasing Ras prenylation.

    Science.gov (United States)

    Shen, Ning; Shao, Yue; Lai, Shan-Shan; Qiao, Long; Yang, Run-Lin; Xue, Bin; Pan, Fei-Yan; Chen, Hua-Qun; Li, Chao-Jun

    2011-12-01

    Cigarette smoke activates the extracellular signal-regulated kinase (ERK) 1/2 mitogen activated-protein kinase pathway, which, in turn, is responsible for early growth response gene-1 (EGR-1) activation. Here we provide evidence that EGR-1 activation can also reactivate ERK 1/2 mitogen activated-protein kinase through a positive feedback loop through its target gene (geranylgeranyl diphosphate synthase) GGPPS. For the first time, the GGPPS gene is identified as a target of EGR-1, as EGR-1 can directly bind to the predicted consensus-binding site in the GGPPS promoter and regulate its transcription. Long-term observations show that there are two ERK 1/2 phosphorylation peaks after cigarette smoke extract stimulation in human lung epithelial Beas-2B cells. The first peak (at 10 minutes) is responsible for EGR-1 accumulation, and the second (at 4 hours) is diminished after the disruption of EGR-1 transcriptional activity. EGR-1 overexpression enhances Ras prenylation and membrane association in a GGPPS-dependent manner, and it augments ERK 1/2 activation. Likewise, a great reduction of the second peak of ERK 1/2 phosphorylation is observed during long-term cigarette smoke extract stimulation in cells where GGPPS is disrupted. Thus, we have uncovered an intricate positive feedback loop in which ERK 1/2-activated EGR-1 promotes ERK 1/2 reactivation through promoting GGPPS transcription, which might affect cigarette smoke-related lung pathological processes.

  15. Comparison of different extraction methods and HPLC quantification of prenylated and unprenylated phenylpropanoids in raw Italian propolis.

    Science.gov (United States)

    Taddeo, Vito Alessandro; Epifano, Francesco; Fiorito, Serena; Genovese, Salvatore

    2016-09-10

    In this paper the presence of selected prenylated and unprenylated phenylpropanoids, namely ferulic acid 1, boropinic acid 2, 4'-geranyloxyferulic acid 3, umbelliferone 4, 7-isopentenyloxycoumarin 5, and auraptene 6, have been determined in Italian raw propolis after having been extracted with different methodologies. An aqueous solution of β-cyclodextrin was the best extraction method for ferulic acid 1, treatment with indifferently EtOH or aqueous β-cyclodextrin were the most effective one for umbelliferone 4, boropinic acid 2 gave the best yields either with H2O/β-cyclodextrin or olive oil treatment or in biphasic systems, maceration with biphasic mixtures of aqueous β-cyclodextrin and olive oil was seen to be the most effective procedure for 7-isopentenyloxycoumarin 5, the only method providing significant quantities of 4'-geranyloxyferulic acid 3 was the maceration of raw propolis with olive oil, and finally auraptene 4 was best extracted with absolute EtOH. "Classic" maceration in general performed better than ultrasound-assisted one.

  16. Molecular cloning and catalytic activity of a membrane-bound prenyl diphosphate phosphatase from Croton stellatopilosus Ohba.

    Science.gov (United States)

    Nualkaew, Natsajee; Guennewich, Nils; Springob, Karin; Klamrak, Anuwatchakit; De-Eknamkul, Wanchai; Kutchan, Toni M

    2013-07-01

    Geranylgeraniol (GGOH), a bioactive acyclic diterpene with apoptotic induction activity, is the immediate precursor of the commercial anti-peptic, plaunotol (18-hydroxy geranylgeraniol), which is found in Croton stellatopilosus (Ohba). From this plant, a cDNA encoding a prenyl diphosphate phosphatase (CsPDP), which catalyses the dephosphorylation of geranylgeranyl diphosphate (GGPP) to GGOH, was isolated using a PCR approach. The full-length cDNA contained 888bp and encoded a 33.6 kDa protein (295 amino acids) that was phylogenetically grouped into the phosphatidic acid phosphatase (PAP) enzyme family. The deduced amino acid sequence showed 6 hydrophobic transmembrane regions with 57-85% homology to the sequences of other plant PAPs. The recombinant CsPDP and its 4 truncated constructs exhibited decreasing dephosphorylation activities relative to the lengths of the N-terminal deletions. While the full-length CsPDP successfully performed the two sequential monodephosphorylation steps on GGPP to form GGOH, the larger N-terminal deletion in the truncated enzymes appeared to specifically decrease the catalytic efficiency of the second monodephosphorylation step. The information presented here on the CsPDP cDNA and factors affecting the dephosphorylation activity of its recombinant protein may eventually lead to the discovery of the specific GGPP phosphatase gene and enzyme that are involved in the formation of GGOH in the biosynthetic pathway of plaunotol in C. stellatopilosus.

  17. Prenyl Ammonium Salts – New Carriers for Gene Delivery: A B16-F10 Mouse Melanoma Model

    Science.gov (United States)

    Grecka, Emilia; Statkiewicz, Malgorzata; Gorska, Agnieszka; Biernacka, Marzena; Grygorowicz, Monika Anna; Masnyk, Marek; Chmielewski, Marek; Gawarecka, Katarzyna; Chojnacki, Tadeusz; Swiezewska, Ewa; Malecki, Maciej

    2016-01-01

    Purpose Prenyl ammonium iodides (Amino-Prenols, APs), semi-synthetic polyprenol derivatives were studied as prospective novel gene transfer agents. Methods AP-7, -8, -11 and -15 (aminoprenols composed of 7, 8, 11 or 15 isoprene units, respectively) were examined for their capacity to form complexes with pDNA, for cytotoxicity and ability to transfect genes to cells. Results All the carriers were able to complex DNA. The highest, comparable to commercial reagents, transfection efficiency was observed for AP-15. Simultaneously, AP-15 exhibited the lowest negative impact on cell viability and proliferation—considerably lower than that of commercial agents. AP-15/DOPE complexes were also efficient to introduce pDNA to cells, without much effect on cell viability. Transfection with AP-15/DOPE complexes influenced the expression of a very few among 44 tested genes involved in cellular lipid metabolism. Furthermore, complexes containing AP-15 and therapeutic plasmid, encoding the TIMP metallopeptidase inhibitor 2 (TIMP2), introduced the TIMP2 gene with high efficiency to B16-F10 melanoma cells but not to B16-F10 melanoma tumors in C57BL/6 mice, as confirmed by TIMP2 protein level determination. Conclusion Obtained results indicate that APs have a potential as non-viral vectors for cell transfection. PMID:27088717

  18. Prenyl Ammonium Salts--New Carriers for Gene Delivery: A B16-F10 Mouse Melanoma Model.

    Science.gov (United States)

    Grecka, Emilia; Statkiewicz, Malgorzata; Gorska, Agnieszka; Biernacka, Marzena; Grygorowicz, Monika Anna; Masnyk, Marek; Chmielewski, Marek; Gawarecka, Katarzyna; Chojnacki, Tadeusz; Swiezewska, Ewa; Malecki, Maciej

    2016-01-01

    Prenyl ammonium iodides (Amino-Prenols, APs), semi-synthetic polyprenol derivatives were studied as prospective novel gene transfer agents. AP-7, -8, -11 and -15 (aminoprenols composed of 7, 8, 11 or 15 isoprene units, respectively) were examined for their capacity to form complexes with pDNA, for cytotoxicity and ability to transfect genes to cells. All the carriers were able to complex DNA. The highest, comparable to commercial reagents, transfection efficiency was observed for AP-15. Simultaneously, AP-15 exhibited the lowest negative impact on cell viability and proliferation--considerably lower than that of commercial agents. AP-15/DOPE complexes were also efficient to introduce pDNA to cells, without much effect on cell viability. Transfection with AP-15/DOPE complexes influenced the expression of a very few among 44 tested genes involved in cellular lipid metabolism. Furthermore, complexes containing AP-15 and therapeutic plasmid, encoding the TIMP metallopeptidase inhibitor 2 (TIMP2), introduced the TIMP2 gene with high efficiency to B16-F10 melanoma cells but not to B16-F10 melanoma tumors in C57BL/6 mice, as confirmed by TIMP2 protein level determination. Obtained results indicate that APs have a potential as non-viral vectors for cell transfection.

  19. Eosinofil Sel Penyaji Antigen

    Directory of Open Access Journals (Sweden)

    Safari Wahyu Jatmiko

    2015-04-01

    Full Text Available Sel eosinofil merupakan jenis sel lekosit yang terlibat dalam berbagai patogenesis penyakit. Sel eosinofil pada awalnya dikenal sebagai sel efektor  dari sistem imunitas alamiah. Akan tetapi, kemampuan sel eosinofil dalam memfagositosis patogen menimbulkan dugaan bahwa sel eosinofil ikut berperan sebagai sel penyaji antigen. Hal ini dianalogikan dengan sel makrofag dan sel dendritik yang bisa memfagositosis dan menyajikan antigen sebagai hasil dari degradasi patogen yang difagositosis. Untuk menjawab permasalahan ini, penulis melakukan penelusuran artikel tentang eosinofil sebagai sel penyaji antigen melalui US National Library of Medicine National Institute of Healthdengan kata kunci eoshinophil dan antigen presenting cell. Hasil penelusuran adalah ditemukannya 10 artikel yang relevan dengan topik. Hasil dari sintesis kesepuluh jurnal tersebut adalah sel eosinofil mampu berperan sebagai sel penyaji antigen yang profesional (professionalantigenpresentng cell

  20. An Evaluative History of Bisphosphonate Drugs: Dual Physiologic Effects of Pyrophosphate as Inspiration for a Novel Pharmaceutical Class

    Science.gov (United States)

    2016-01-01

    The documented history of the development of the bisphosphonate drugs is reviewed in sufficient detail to permit independent evaluation of the consistency of the conclusions reached from the available data. The evidence developed during the early interval of these studies 1960–1975 was sufficient to establish that pyrophosphate shares the subsequently established dual bisphosphonate characteristics of bone resorption inhibition and prevention of tissue mineralization. PMID:27800209

  1. Fast ionic conduction in tetravalent metal pyrophosphate-alkali carbonate composites: New potential electrolytes for intermediate-temperature fuel cells

    Science.gov (United States)

    Singh, Bhupendra; Bhardwaj, Aman; Gautam, Sandeep K.; Kumar, Devendra; Parkash, Om; Kim, In-Ho; Song, Sun-Ju

    2017-03-01

    Here we present a report on synthesis and characterization of tetravalent metal pyrophosphate (TMP) and alkali carbonate (A2CO3; A = Li and/or Na) composites. The TMP-carbonate composites are prepared by mixing indium-doped tin pyrophosphate or yttrium-doped zirconium pyrophosphate with Li2CO3 or an eutectic mixture of Li2CO3-Na2CO3 in different wt.% ratios. The phase composition, microstructure and electrical conductivity of the sintered specimen are analyzed. In addition, the effect of different TMP and A2CO3 phases is investigated. A maximum ionic conductivity of 5.5 × 10-2 S cm-1 at 630 °C is observed in this study with a Sn0.9In0.1P2O7-Li2CO3 composite. Based on the literature data, TMP-carbonate composites can be considered to be primarily a proton and oxygen-ion co-ionic conductor and, therefore, have strong potential as electrolytes in fuel cells in 500-700 °C range.

  2. Structure of human farnesyl pyrophosphate synthase in complex with an aminopyridine bisphosphonate and two molecules of inorganic phosphate

    Energy Technology Data Exchange (ETDEWEB)

    Park, Jaeok [McGill University, 3655 Promenade Sir William Osler, Montreal, QC H3G 1Y6 (Canada); Lin, Yih-Shyan [McGill University, 801 Rue Sherbrooke Ouest, Montreal, QC H3A 0B8 (Canada); Tsantrizos, Youla S. [McGill University, 3655 Promenade Sir William Osler, Montreal, QC H3G 1Y6 (Canada); McGill University, 801 Rue Sherbrooke Ouest, Montreal, QC H3A 0B8 (Canada); McGill University, 3649 Promenade Sir William Osler, Montreal, QC H3G 0B1 (Canada); Berghuis, Albert M., E-mail: albert.berghuis@mcgill.ca [McGill University, 3655 Promenade Sir William Osler, Montreal, QC H3G 1Y6 (Canada); McGill University, 3649 Promenade Sir William Osler, Montreal, QC H3G 0B1 (Canada); McGill University, 3775 Rue University, Montreal, QC H3A 2B4 (Canada)

    2014-02-19

    A co-crystal structure of human farnesyl pyrophosphate synthase in complex with an aminopyridine bisphosphonate, YS0470, and two molecules of inorganic phosphate has been determined. The identity of the phosphate ligands was confirmed by anomalous diffraction data. Human farnesyl pyrophosphate synthase (hFPPS) produces farnesyl pyrophos@@phate, an isoprenoid essential for a variety of cellular processes. The enzyme has been well established as the molecular target of the nitrogen-containing bisphosphonates (N-BPs), which are best known for their antiresorptive effects in bone but are also known for their anticancer properties. Crystal structures of hFPPS in ternary complexes with a novel bisphosphonate, YS0470, and the secondary ligands inorganic phosphate (P{sub i}), inorganic pyrophosphate (PP{sub i}) and isopentenyl pyrophosphate (IPP) have recently been reported. Only the co-binding of the bisphosphonate with either PP{sub i} or IPP resulted in the full closure of the C-@@terminal tail of the enzyme, a conformational change that is required for catalysis and that is also responsible for the potent in vivo efficacy of N-BPs. In the present communication, a co-crystal structure of hFPPS in complex with YS0470 and two molecules of P{sub i} is reported. The unusually close proximity between these ligands, which was confirmed by anomalous diffraction data, suggests that they interact with one another, with their anionic charges neutralized in their bound state. The structure also showed the tail of the enzyme to be fully disordered, indicating that simultaneous binding of two P{sub i} molecules with a bisphosphonate cannot induce the tail-closing conformational change in hFPPS. Examination of homologous FPPSs suggested that this ligand-dependent tail closure is only conserved in the mammalian proteins. The prevalence of P{sub i}-bound hFPPS structures in the PDB raises a question regarding the in vivo relevance of P{sub i} binding to the function of the enzyme.

  3. Pyrophosphate levels strongly influence ascorbate and starch content in tomato fruit

    Directory of Open Access Journals (Sweden)

    Sonia eOsorio

    2013-08-01

    Full Text Available Ascorbate (vitamin C deficiency leads to low immunity, scurvy, and other human diseases and is therefore a global health problem. Given that plants are major ascorbate sources for humans, biofortification of this vitamin in our foodstuffs is of considerable importance. Ascorbate is synthetized by a number of alternative pathways: (i from the glycolytic intermediates D-glucose-6P (the key intermediates are GDP-D-mannose and L-galactose, (ii from the breakdown of the cell wall polymer pectin which uses the methyl ester of D-galacturonic acid as precursor and (iii from myo-inositol as precursor via myo-inositol oxygenase. We report here the engineering of fruit-specific overexpression of a bacterial pyrophosphatase, which hydrolyzes the inorganic pyrophosphate (PPi to orthophosphate (Pi. This strategy resulted in increased vitamin C levels up to 2.5 fold in ripe fruit as well as increasing in the major sugars, sucrose and glucose, yet decreasing the level of starch. When considered together, these finding indicate an intimate linkage between ascorbate and sugar biosynthesis in plants. Moreover, the combined data reveal the importance of PPi metabolism in tomato fruit metabolism and development.

  4. Modulation of hexa-acyl pyrophosphate lipid A population under Escherichia coli phosphate (Pho) regulon activation.

    Science.gov (United States)

    Lamarche, Martin G; Kim, Sang-Hyun; Crépin, Sébastien; Mourez, Michael; Bertrand, Nicolas; Bishop, Russell E; Dubreuil, J Daniel; Harel, Josée

    2008-08-01

    Environmental phosphate is an important signal for microorganism gene regulation, and it has recently been shown to trigger some key bacterial virulence mechanisms. In many bacteria, the Pho regulon is the major circuit involved in adaptation to phosphate limitation. The Pho regulon is controlled jointly by the two-component regulatory system PhoR/PhoB and by the phosphate-specific transport (Pst) system, which both belong to the Pho regulon. We showed that a pst mutation results in virulence attenuation in extraintestinal pathogenic Escherichia coli (ExPEC) strains. Our results indicate that the bacterial cell surface of the pst mutants is altered. In this study, we show that pst mutants of ExPEC strains display an increased sensitivity to different cationic antimicrobial peptides and vancomycin. Remarkably, the hexa-acylated 1-pyrophosphate form of lipid A is significantly less abundant in pst mutants. Among differentially expressed genes in the pst mutant, lpxT coding for an enzyme that transfers a phosphoryl group to lipid A, forming the 1-diphosphate species, was found to be downregulated. Our results strongly suggest that the Pho regulon is involved in lipid A modifications, which could contribute to bacterial surface perturbations. Since the Pho regulon and the Pst system are conserved in many bacteria, such a lipid A modification mechanism could be widely distributed among gram-negative bacterial species.

  5. Crystallization and preliminary neutron diffraction experiment of human farnesyl pyrophosphate synthase complexed with risedronate.

    Science.gov (United States)

    Yokoyama, Takeshi; Ostermann, Andreas; Mizuguchi, Mineyuki; Niimura, Nobuo; Schrader, Tobias E; Tanaka, Ichiro

    2014-04-01

    Nitrogen-containing bisphosphonates (N-BPs), such as risedronate and zoledronate, are currently used as a clinical drug for bone-resorption diseases and are potent inhibitors of farnesyl pyrophosphate synthase (FPPS). X-ray crystallographic analyses of FPPS with N-BPs have revealed that N-BPs bind to FPPS with three magnesium ions and several water molecules. To understand the structural characteristics of N-BPs bound to FPPS, including H atoms and hydration by water, neutron diffraction studies were initiated using BIODIFF at the Heinz Maier-Leibnitz Zentrum (MLZ). FPPS-risedronate complex crystals of approximate dimensions 2.8 × 2.5 × 1.5 mm (∼3.5 mm(3)) were obtained by repeated macro-seeding. Monochromatic neutron diffraction data were collected to 2.4 Å resolution with 98.4% overall completeness. Here, the first successful neutron data collection from FPPS in complex with N-BPs is reported.

  6. Drug-induced modulation of Tc-99m pyrophosphate tissue distribution: what is involved

    Energy Technology Data Exchange (ETDEWEB)

    Wahner, H.W.; Dewanjee, M.K.

    1981-06-01

    More than ten years after their introduction, Tc-99m-labeled phosphates and phosphonates (TcP) continue to be of interest to the investigator and to hold promise for new clinical applications in the future. Initially, TcP compounds were valued because of their bone-seeking properties. Emphasis shifted from bone to soft tissue when Bonte et al. introduced Tc-99m-labeled pyrophosphate (TcPPi) for myocardial infarct scanning. Detailed information about TcPPi uptake in ischemic and necrotic myocardial tissue at the subcellular level has accumulated. Therefore, understanding of the mechanism of TcPPi uptake in infarcted myocardium is more detailed than understanding of uptake by bone. A new, and potentially powerful, approach to the use of TcP is being proposed by Carr et al. The authors attempt to modulate favorably the tissue distribution of TcPPi by prior administration of drugs in pharmacological quantities. The authors demonstrate that uptake of TcPPi can be enhanced in the necrotic myocardium, uptake by bone can be reduced, and the lesion-to-blood ratio can be altered favorably when vitamin D/sub 3/ or desoxycorticosterone acetate (DOCA) is administered in pharmacological doses before the TcPPi injection. A short review is presented of background information helpful for interpreting the drug effects on TcPPi uptake in bone or necrotic myocardial tissue.

  7. Novel phosphate-activated macrophages prevent ectopic calcification by increasing extracellular ATP and pyrophosphate

    Science.gov (United States)

    Villa-Bellosta, Ricardo; Hamczyk, Magda R.; Andrés, Vicente

    2017-01-01

    Purpose Phosphorus is an essential nutrient involved in many pathobiological processes. Less than 1% of phosphorus is found in extracellular fluids as inorganic phosphate ion (Pi) in solution. High serum Pi level promotes ectopic calcification in many tissues, including blood vessels. Here, we studied the effect of elevated Pi concentration on macrophage polarization and calcification. Macrophages, present in virtually all tissues, play key roles in health and disease and display remarkable plasticity, being able to change their physiology in response to environmental cues. Methods and results High-throughput transcriptomic analysis and functional studies demonstrated that Pi induces unpolarized macrophages to adopt a phenotype closely resembling that of alternatively-activated M2 macrophages, as revealed by arginine hydrolysis and energetic and antioxidant profiles. Pi-induced macrophages showed an anti-calcifying action mediated by increased availability of extracellular ATP and pyrophosphate. Conclusion We conclude that the ability of Pi-activated macrophages to prevent calcium-phosphate deposition is a compensatory mechanism protecting tissues from hyperphosphatemia-induced pathologic calcification. PMID:28362852

  8. Stabilization through precipitation in a system of colloidal iron(III) pyrophosphate salts.

    Science.gov (United States)

    van Leeuwen, Y Mikal; Velikov, Krassimir P; Kegel, Willem K

    2012-09-01

    The ionic strength of a solution decreases during the precipitation of an insoluble salt, which can cause an initially unstable colloidal system to stabilize during its formation. We show this effect in the precipitation and aging of colloidal iron(III) pyrophosphate, where we observe two distinct stages in the aggregation process. The first stage is the formation of nanoparticles that immediately aggregate into clusters with sizes on the order of 200 nm. In the second stage these clusters slowly grow in size but remain in dispersion for days, even months for dialyzed systems. Eventually these clusters become macroscopically large and sediment out of dispersion. Noting the clear instability of the nanoparticles, it is interesting to find two stages in their aggregation even without the use of additives such as surface active molecules. This is explained by accounting for the rapid decrease of ionic strength during precipitation, rendering the nanoparticles relatively stable when precipitation is complete. Calculating the interaction potentials for this scenario we find good agreement with the experimental observations. These results indicate that coupling of ionic strength to aggregation state can be significant and should be taken into account when considering colloidal stability of insoluble salts.

  9. Enhancing ATP-based bacteria and biofilm detection by enzymatic pyrophosphate regeneration.

    Science.gov (United States)

    Lee, Hui-Ju; Ho, Ming-Rong; Bhuwan, Manish; Hsu, Ching-Yi; Huang, Meng-Shun; Peng, Hwei-Ling; Chang, Hwan-You

    2010-04-15

    The manufacturing processes of many electronic and medical products demand the use of high-quality water. Hence the water supply systems for these processes are required to be examined regularly for the presence of microorganisms and microbial biofilms. Among commonly used bacteria detection approaches, the ATP luminescence assay is a rapid, sensitive, and easy to perform method. The aim of this study is to investigate whether ATP regeneration from inorganic pyrophosphate, a product of the ATP luminescence assay, can stabilize the bioluminescence signals in ATP detection. ADPglc pyrophosphorylase (AGPPase), which catalyzes the synthesis of ATP from PP(i) in the presence of ADPglc, was selected because the system yields much lower luminescence background than the commercially available ATP sulfurylase/adenosine 5'-phosphosulfate (APS) system which was broadly used in pyrosequencing technology. The AGPPase-based assay could be used to measure both PP(i) and ATP quantitatively and shows 1.5- to 4.0-fold slight increases in a 10-min assay. The method could also be used to stabilize the luminescence signals in detection of Escherichia coli, Pseudomonas aeruginosa, and Bacillus cereus in either broth or biofilm. These findings suggest that the AGPPase-based ATP regeneration system will find many practical applications such as detection of bacterial biofilm in water pipelines.

  10. Pyrophosphate coupling with chelant-enhanced soil flushing of field contaminated soils for heavy metal extraction.

    Science.gov (United States)

    Yan, Dickson Y S; Lo, Irene M C

    2012-01-15

    This study investigated the influence of flushing duration, [S,S]-ethylenediaminedisuccinic acid (EDDS) dosage, humic acid and various combinations of ethylenediaminetetraacetic acid (EDTA), EDDS and tetrasodium pyrophosphate (Na(4)P(2)O(7)) on metal extraction during soil flushing, through column experiments. A lesser extent of enhancement in metal extraction efficiencies was found when the flushing duration and the dosage of EDDS was doubled, compared to their efficiencies measured at pore volume 100. Metal extraction efficiency was mainly influenced by the initial metal distribution in the soils rather than the flushing duration and the EDDS-to-metal molar ratio. Humic acid of less than 10mg/L as dissolved organic carbon (DOC) posed an insignificant effect on metal extraction during EDDS enhanced soil flushing. The extraction rate of Ni by EDTA and EDDS was time dependent, and was initially fast in the case of EDDS, whereas it was slow for EDTA. However, the overall Ni extraction efficiency by EDTA was higher when the flushing time was longer. Na(4)P(2)O(7) promoted the mineral dissolution which enhanced the metal extraction as a result of soil disruption. The order of metal extraction by Na(4)P(2)O(7) was Ni>Cr>Cu, probably be due to the different affinities between metals and P(2)O(7)(4-). Copyright © 2011 Elsevier B.V. All rights reserved.

  11. Regulation of the Saccharomyces cerevisiae DPP1-encoded diacylglycerol pyrophosphate phosphatase by zinc.

    Science.gov (United States)

    Han, G S; Johnston, C N; Chen, X; Athenstaedt, K; Daum, G; Carman, G M

    2001-03-30

    The DPP1 gene, encoding diacylglycerol pyrophosphate (DGPP) phosphatase from Saccharomyces cerevisiae, has recently been identified as a zinc-regulated gene, and it contains a putative zinc-responsive element (UAS(ZRE)) in its promoter. In this work we examined the hypothesis that expression of DGPP phosphatase was regulated by zinc availability. The deprivation of zinc from the growth medium resulted in a time- and dose-dependent induction of beta-galactosidase activity driven by a P(DPP1)-lacZ reporter gene. This regulation was dependent on the UAS(ZRE) in the DPP1 promoter and was mediated by the Zap1p transcriptional activator. Induction of the DGPP phosphatase protein and activity by zinc deprivation was demonstrated by immunoblot analysis and measurement of the dephosphorylation of DGPP. The regulation pattern of DGPP phosphatase in mutants defective in plasma membrane (Zrt1p and Zrt2p) and vacuolar membrane (Zrt3p) zinc transporters indicated that enzyme expression was sensitive to the cytoplasmic levels of zinc. DGPP phosphatase activity was inhibited by zinc by a mechanism that involved formation of DGPP-zinc complexes. Studies with well characterized subcellular fractions and by indirect immunofluorescence microscopy revealed that the DGPP phosphatase enzyme was localized to the vacuolar membrane.

  12. Positive selection and functional divergence of farnesyl pyrophosphate synthase genes in plants.

    Science.gov (United States)

    Qian, Jieying; Liu, Yong; Chao, Naixia; Ma, Chengtong; Chen, Qicong; Sun, Jian; Wu, Yaosheng

    2017-02-04

    Farnesyl pyrophosphate synthase (FPS) belongs to the short-chain prenyltransferase family, and it performs a conserved and essential role in the terpenoid biosynthesis pathway. However, its classification, evolutionary history, and the forces driving the evolution of FPS genes in plants remain poorly understood. Phylogeny and positive selection analysis was used to identify the evolutionary forces that led to the functional divergence of FPS in plants, and recombinant detection was undertaken using the Genetic Algorithm for Recombination Detection (GARD) method. The dataset included 68 FPS variation pattern sequences (2 gymnosperms, 10 monocotyledons, 54 dicotyledons, and 2 outgroups). This study revealed that the FPS gene was under positive selection in plants. No recombinant within the FPS gene was found. Therefore, it was inferred that the positive selection of FPS had not been influenced by a recombinant episode. The positively selected sites were mainly located in the catalytic center and functional areas, which indicated that the 98S and 234D were important positively selected sites for plant FPS in the terpenoid biosynthesis pathway. They were located in the FPS conserved domain of the catalytic site. We inferred that the diversification of FPS genes was associated with functional divergence and could be driven by positive selection. It was clear that protein sequence evolution via positive selection was able to drive adaptive diversification in plant FPS proteins. This study provides information on the classification and positive selection of plant FPS genes, and the results could be useful for further research on the regulation of triterpenoid biosynthesis.

  13. Pyruvate:NADP+ oxidoreductase is stabilized by its cofactor, thiamin pyrophosphate, in mitochondria of Euglena gracilis.

    Science.gov (United States)

    Nakazawa, Masami; Takenaka, Shigeo; Ueda, Mitsuhiro; Inui, Hiroshi; Nakano, Yoshihisa; Miyatake, Kazutaka

    2003-03-15

    Pyruvate:NADP(+) oxidoreductase (PNO) is a thiamin pyrophosphate (TPP)-dependent enzyme that plays a central role in the respiratory metabolism of Euglena gracilis, which requires thiamin for growth. When thiamin was depleted in Euglena cells, PNO protein level was greatly reduced, but its mRNA level was barely changed. In addition, a large part of PNO occurred as an apoenzyme lacking TPP in the deficient cells. The PNO protein level increased rapidly, without changes in the mRNA level, after supplementation of thiamin into its deficient cells. In the deficient cells, in contrast to the sufficient ones, a steep decrease in the PNO protein level was induced when the cells were incubated with cycloheximide. Immunofluorescence microscopy indicated that most of the PNO localized in the mitochondria in either the sufficient or the deficient cells. These findings suggest that PNO is readily degraded when TPP is not provided in mitochondria, and consequently the PNO protein level is greatly reduced by thiamin deficiency in E. gracilis.

  14. Diacylglycerol pyrophosphate inhibits the alpha-amylase secretion stimulated by gibberellic acid in barley aleurone.

    Science.gov (United States)

    Racagni, Graciela; Villasuso, Ana L; Pasquaré, Susana J; Giusto, Norma M; Machado, Estela

    2008-11-01

    ABA plays an important regulatory role in seed germination because it inhibits the response to GA in aleurone, a secretory tissue surrounding the endosperm. Phosphatidic acid (PA) is a well-known intermediary in ABA signaling, but the role of diacylglycerol pyrophosphate (DGPP) in germination processes is not clearly established. In this study, we show that PA produced by phospholipase D (E.C. 3.1.4.4) during the antagonist effect of ABA in GA signaling is rapidly phosphorylated by phosphatidate kinase (PAK) to DGPP. This is a crucial fact for aleurone function because exogenously added dioleoyl-DGPP inhibits secretion of alpha-amylase (E.C. 3.2.1.1). Aleurone treatment with ABA and 1-butanol results in normal secretory activity, and this effect is reversed by addition of dioleoyl-DGPP. We also found that ABA decreased the activity of an Mg2+-independent, N-ethylmaleimide-insensitive form of phosphatidate phosphohydrolase (PAP2) (E.C. 3.1.3.4), leading to reduction of PA dephosphorylation and increased PAK activity. Sequence analysis using Arabidopsis thaliana lipid phosphate phosphatase (LPP) sequences as queries identified two putative molecular homologues, termed HvLPP1 and HvLPP2, encoding putative Lpps with the presence of well-conserved structural Lpp domains. Our results are consistent with a role of DGPP as a regulator of ABA antagonist effect in GA signaling and provide evidence about regulation of PA level by a PAP2 during ABA response in aleurone.

  15. Formation of phosphonates and pyrophosphates in the reactions of chlorophosphate esters with strong organic bases

    Indian Academy of Sciences (India)

    K V P Pavan Kumar; K Praveen Kumar; M Vijjulatha; K C Kumara Swamy

    2004-11-01

    The compounds S(6--Bu-4-Me-C6H2O)2P(O)Cl (1), CH2(6--Bu-4-Me-C6H2O)2P(O)Cl (2) and (2,2'-C20H12O2)P(O)Cl (3) react with diazabicycloundecene (DBU) to give rise to, predominantly, the phosphonate compounds [S(6--Bu-4-Me-C6H2O)2P(O)(DBU)]+[Cl]- (4), [CH2(6--Bu-4-Me-C6H2O)2P(O) (DBU)]+[Cl]- (5) and [(2,2'-C20H12O2)P(O)(DBU)]+[Cl]- (6). The first two compounds could be isolated in the pure state. In analogous reactions of 1 and 2 with diazabicyclononene (DBN) or N-methyl imidazole, only the pyrophosphates [S(6--Bu-4-Me-C6H2O)2P(O)]2O (7) and [CH2(6--Bu-4-Me-C6H2O)2P(O)]2O (8) could be isolated, although the reaction mixture showed several other compounds in the phosphorus NMR. A possible pathway for the formation of phosphonate salts is proposed. The X-ray crystal structures of 4, 7 and 8 are also discussed.

  16. CEA (Carcinoembryonic Antigen) Test

    Science.gov (United States)

    ... as: CEA Formal name: Carcinoembryonic Antigen Related tests: Tumor Markers , CSF Analysis , Body Fluid Analysis , CA 19-9 , Calcitonin , AFP Tumor Markers All content on Lab Tests Online has been ...

  17. A new dimeric dihydrochalcone and a new prenylated flavone from the bud covers of Artocarpus altilis: potent inhibitors of cathepsin K.

    Science.gov (United States)

    Patil, Ashok D; Freyer, Alan J; Killmer, Lew; Offen, Priscilla; Taylor, Paul B; Votta, Bartholomew J; Johnson, Randall K

    2002-04-01

    A MeOH/CH(2)Cl(2) extract of the bud covers of Artocarpus altilis collected in Micronesia showed activity in a cathepsin K inhibition assay. In addition to the three known flavonoids isolated from the bud covers of this species, two new compounds have been identified whose structures were determined on the basis of spectral data. These compounds include a dimeric dihydrochalcone, cycloaltilisin 6 (2), and a new prenylated flavone, cycloaltilisin 7 (3). Novel compounds 2 and 3 have IC(50) values of 98 and 840 nM, respectively, in cathepsin inhibition.

  18. A Comparative Study on the Metabolism of Epimedium koreanum Nakai-Prenylated Flavonoids in Rats by an Intestinal Enzyme (Lactase Phlorizin Hydrolase) and Intestinal Flora

    OpenAIRE

    Jing Zhou; Yan Chen; Ying Wang; Xia Gao; Ding Qu; Congyan Liu

    2013-01-01

    The aim of this study was to compare the significance of the intestinal hydrolysis of prenylated flavonoids in Herba Epimedii by an intestinal enzyme and flora. Flavonoids were incubated at 37 °C with rat intestinal enzyme and intestinal flora. HPLC-UV was used to calculate the metabolic rates of the parent drug in the incubation and LC/MS/MS was used to determine the chemical structures of metabolites generated by different flavonoid glycosides. Rates of flavonoid metabolism by rat intestin...

  19. The utility of alizarin red s staining in calcium pyrophosphate dihydrate crystal deposition disease.

    Science.gov (United States)

    Yamakawa, Koji; Iwasaki, Hiroshi; Masuda, Ikuko; Ohjimi, Yuko; Honda, Itsuo; Saeki, Kazuhiko; Zhang, Jingfan; Shono, Eisuke; Naito, Masatoshi; Kikuchi, Masahiro

    2003-05-01

    To determine the most suitable staining method for preservation and detection of calcium pyrophosphate dihydrate (CPPD) crystals in histological sections of patients with CPPD crystal deposition disease. Paraffin sections of CPPD crystal-bearing tissues of 31 patients were stained with hematoxylin and eosin (H&E) and Alizarin red S (ARS). For H&E, the sections were treated with Mayer's hematoxylin (pH 2.3) for 5 min and with eosin alcohol (pH 4.1) for 1 min. For ARS, 1% ARS dissolved in distilled water was adjusted to pH 6.4 by adding 0.1% ammonia solution drop by drop while stirring. As controls, unstained sections were soaked in 1% citric acid monohydrate solution (CAMS, pH 2.3) for 5 or 10 min. The histological preparations were examined under a compensated polarized light using a first-order red compensator. We counted the number of weakly positive birefringent CPPD crystals in 3 high power fields (HPF, 0.272 mm2). CPPD crystals were seen clearly in most specimens stained with ARS, but were markedly reduced in tissue sections stained with H&E or CAMS. The number of CPPD crystals detected in sections stained by ARS (1723 +/- 683 per 3 HPF, mean +/- standard deviation) was significantly higher compared with H&E, CAMS (5 min), and CAMS (10 min) (401 +/- 374, 1022 +/- 616, and 494 +/- 636 per 3 HPF, respectively; p < 0.001, each). Standard H&E staining reduces the number of visible CPPD crystals, probably due to the strong acidity of both hematoxylin and eosin solutions, whereas the ARS stain seems to preserve a large number of CPPD crystals. The utility of ARS staining may improve the identification of CPPD crystals and contribute to a correct diagnosis of CPPD crystal deposition.

  20. Effect of sodium acid pyrophosphate on ranitidine bioavailability and gastrointestinal transit time.

    Science.gov (United States)

    Koch, K M; Parr, A F; Tomlinson, J J; Sandefer, E P; Digenis, G A; Donn, K H; Powell, J R

    1993-07-01

    During development of a ranitidine effervescent oral solution dosage form, a marked decrease was observed in the extent of ranitidine absorption relative to the conventional oral tablet. Two studies were conducted in healthy volunteers to confirm the involvement of an excipient, SAPP (sodium acid pyrophosphate), and the mechanism of interaction, altered gastrointestinal transit. The first study (n = 12) involved single-dose crossover comparisons of (A) 150 mg ranitidine with 1132 mg SAPP versus (B) 150 mg ranitidine and (C) 150 mg ranitidine with all the effervescent tablet excipients except SAPP versus (D) a 150-mg ranitidine effervescent tablet, all administered as oral solutions. Serum ranitidine AUC, Cmax, and tmax were compared using two one-sided t test 90% confidence intervals (CI). Comparing treatments A to B and D to C, all 90% CI were below the 80-120% range, indicating significantly less extensive ranitidine absorption (54% based on AUC) from the oral solutions containing SAPP. The second study (n = 12) was a single-dose crossover comparing 50 microCi 111 InCl solutions with and without 1132 mg SAPP. Gastrointestinal transit times, determined by scintigraphic imaging, were compared between treatments. Gastric emptying time was unchanged, but small intestinal transit time was decreased to 56% in the presence of SAPP. More rapid small intestinal transit associated with an excipient of a solution dosage form apparently resulted in a decreased extent of ranitidine absorption. This observation contradicts the conventional wisdom that oral solutions are unlikely to fall short of bioequivalence relative to solid oral formulations.

  1. Membrane Topology and Biochemical Characterization of the Escherichia coli BacA Undecaprenyl-Pyrophosphate Phosphatase.

    Directory of Open Access Journals (Sweden)

    Guillaume Manat

    Full Text Available Several integral membrane proteins exhibiting undecaprenyl-pyrophosphate (C55-PP phosphatase activity were previously identified in Escherichia coli that belonged to two distinct protein families: the BacA protein, which accounts for 75% of the C55-PP phosphatase activity detected in E. coli cell membranes, and three members of the PAP2 phosphatidic acid phosphatase family, namely PgpB, YbjG and LpxT. This dephosphorylation step is required to provide the C55-P carrier lipid which plays a central role in the biosynthesis of various cell wall polymers. We here report detailed investigations of the biochemical properties and membrane topology of the BacA protein. Optimal activity conditions were determined and a narrow-range substrate specificity with a clear preference for C55-PP was observed for this enzyme. Alignments of BacA protein sequences revealed two particularly well-conserved regions and several invariant residues whose role in enzyme activity was questioned by using a site-directed mutagenesis approach and complementary in vitro and in vivo activity assays. Three essential residues Glu21, Ser27, and Arg174 were identified, allowing us to propose a catalytic mechanism for this enzyme. The membrane topology of the BacA protein determined here experimentally did not validate previous program-based predicted models. It comprises seven transmembrane segments and contains in particular two large periplasmic loops carrying the highly-conserved active site residues. Our data thus provide evidence that all the different E. coli C55-PP phosphatases identified to date (BacA and PAP2 catalyze the dephosphorylation of C55-PP molecules on the same (outer side of the plasma membrane.

  2. Identification of the inorganic pyrophosphate metabolizing, ATP substituting pathway in mammalian spermatozoa.

    Directory of Open Access Journals (Sweden)

    Young-Joo Yi

    Full Text Available Inorganic pyrophosphate (PPi is generated by ATP hydrolysis in the cells and also present in extracellular matrix, cartilage and bodily fluids. Fueling an alternative pathway for energy production in cells, PPi is hydrolyzed by inorganic pyrophosphatase (PPA1 in a highly exergonic reaction that can under certain conditions substitute for ATP-derived energy. Recombinant PPA1 is used for energy-regeneration in the cell-free systems used to study the zymology of ATP-dependent ubiquitin-proteasome system, including the role of sperm-borne proteasomes in mammalian fertilization. Inspired by an observation of reduced in vitro fertilization (IVF rates in the presence of external, recombinant PPA1, this study reveals, for the first time, the presence of PPi, PPA1 and PPi transporter, progressive ankylosis protein ANKH in mammalian spermatozoa. Addition of PPi during porcine IVF increased fertilization rates significantly and in a dose-dependent manner. Fluorometric assay detected high levels of PPi in porcine seminal plasma, oviductal fluid and spermatozoa. Immunofluorescence detected PPA1 in the postacrosomal sheath (PAS and connecting piece of boar spermatozoa; ANKH was present in the sperm head PAS and equatorial segment. Both ANKH and PPA1 were also detected in human and mouse spermatozoa, and in porcine spermatids. Higher proteasomal-proteolytic activity, indispensable for fertilization, was measured in spermatozoa preserved with PPi. The identification of an alternative, PPi dependent pathway for ATP production in spermatozoa elevates our understanding of sperm physiology and sets the stage for the improvement of semen extenders, storage media and IVF media for animal biotechnology and human assisted reproductive therapies.

  3. Knee effusion: ultrasound as a useful tool for the detection of calcium pyrophosphate crystals.

    Science.gov (United States)

    Ruta, Santiago; Catay, Erika; Marin, Josefina; Rosa, Javier; García-Monaco, Ricardo; Soriano, Enrique R

    2016-04-01

    The objective of this study was to evaluate the sensitivity and specificity of ultrasound (US) and conventional radiography (CR) for the detection of calcium pyrophosphate (CPP) crystals in patients with knee effusion. Consecutive patients ≥50 years old with knee effusion were included. All patients underwent arthrocentesis with aspiration of synovial fluid (SF) and subsequent analysis of CPP crystals using plain light and polarizing light microscopy. US and CR of the involved knee were performed immediately after arthrocentesis. CR results were read by an experienced rheumatologist, searching for chondrocalcinosis. US examinations were carried out by an experienced rheumatologist blinded to all clinical and imaging data. The following US abnormal findings were considered indicative of CPP crystals deposition (CPPD): (1) hyperechoic bands within the femoral hyaline cartilage layer, and (2) hyperechoic sparkling spots in meniscal fibrocartilage. A total of 75 knees were evaluated in the same number of patients. Analysis of SF revealed CPP crystals in 15 out of 75 (20 %) knees: all (10) patients with previous diagnosis of CPPD, 3 patients with previous diagnosis of primary knee osteoarthritis (OA) and 2 patients without previous definitive diagnosis of a rheumatic condition. Using SF analysis as reference method, sensitivity and specificity for US findings was 60 and 96.7 %, respectively, while CR showed a sensitivity of 40 % and a specificity of 83.3 %. US results showed high specificity with acceptable sensitivity to detect CPP crystals in patients with knee effusion. Compared with CR, US results had better specificity and sensitivity. US may be used in daily rheumatologic practice when CPPD is suspected.

  4. Pyrophosphate Fructose-6-P 1-Phosphotransferase from Tomato Fruit : Evidence for Change during Ripening.

    Science.gov (United States)

    Wong, J H; Kiss, F; Wu, M X; Buchanan, B B

    1990-10-01

    Three forms of pyrophosphate fructose-6-phosphate 1-phosphotransferase (PFP) were purified from both green and red tomato (Lycopersicon esculentum) fruit: (a) a classical form (designated Q(2)) containing alpha- (66 kilodalton) and beta- (60 kilodalton) subunits; (b) a form (Q(1)) containing a beta-doublet subunit; and (c) a form (Q(0)) that appeared to contain a beta-singlet subunit. Several lines of evidence suggested that the different forms occur under physiological conditions. Q(2) was purified to apparent electrophoretic homogeneity; Q(1) and Q(0) were highly purified, but not to homogeneity. The distribution of the PFP forms from red (versus green) tomato was: Q(2), 29% (90%); Q(1), 47% (6%); and Q(0), 24% (4%). The major difference distinguishing the red from the green tomato enzymes was the fructose-2,6-bisphosphate (Fru-2,6-P(2))-induced change in K(m) for fructose-6-phosphate (Fru-6-P), the ;green forms' showing markedly enhanced affinity on activation (K(m) decrease of 7-9-fold) and the ;red forms' showing either little change (Q(0), Q(1)) or a relatively small (2.5-fold) affinity increase (Q(2)). The results extend our earlier findings with carrot root to another tissue and indicate that forms of PFP showing low or no affinity increase for Fru 6-P on activation by Fru-2,6-P(2) (here Q(1) and Q(0)) are associated with sugar storage, whereas the classical form (Q(2)), which shows a pronounced affinity increase, is more important for starch storage.

  5. Magnetic resonance versus technetium-99m pyrophosphate scintigraphy in the detection of perioperative myocardial necrosis

    Energy Technology Data Exchange (ETDEWEB)

    Monte, Guilherme Urpia; Drager, Luciano Ferreira; Souza, Fabio Solano de Freitas; Avila, Luiz Francisco Rodrigues de; Parga Filho, Jose Rodrigues; Cesar, Luiz Antonio Machado; Izaki, Marisa; Meneghetti, Jose Claudio; Rochitte, Carlos Eduardo; Kalil Filho, Roberto [Universidade de Sao Paulo (USP), SP (Brazil). Hospital das Clinicas. Instituto do Coracao (InCor)]. E-mail: gumonte@cardiol.br

    2008-07-01

    Background: Perioperative myocardial infarction (POMI) is a complication of coronary artery bypass grafting (CABG) with a potential prognostic impact. Technetium-99m pyrophosphate myocardial scintigraphy (MS) is used in the diagnosis of POMI; however it shows a limited sensitivity for subendocardial lesions. Cardiovascular magnetic resonance imaging (CMRI), in turn, has a high accuracy in the detection of myocardial necrosis. Objective: To compare CMRI and MS for the detection of POMI after CABG. Methods: A total of 24 patients with chronic coronary artery disease were studied using the delayed contrast enhanced CMRI and MS before and after CABG by analyzing the development of areas of perioperative myocardial necrosis (POMI). Biochemical markers of myocardial injury (CKMB and troponin I) were also determined before and after surgery. Results: Nineteen patients completed the study. Of these, 6 (32%) presented POMI on CMRI and 4 (21%) on MS (p = NS). Of the 323 left ventricular segments assessed, 17 (5.3%) showed perioperative necrosis on CMRI and 7 (2.2%) on MS (p = 0.013). moderate agreement was observed between the methods (kappa 0.46). There was disagreement regarding the diagnosis of POMI in 4 (21%) cases, most of them with small areas of perioperative necrosis on CMRI which were not visualized on MS. In all cases with POMI on CMRI, significant CKMB and troponin I elevations were observed. Conclusion: Moderate diagnostic agreement was observed between the methods for the detection of POMI, but CMRI enabled visualization of small areas of perioperative myocardial necrosis which were not identified on MS and were associated with elevation of biochemical markers of myocardial injury. (author)

  6. Sensing of pyrophosphate metabolites by Vγ9Vδ2 T cells.

    Directory of Open Access Journals (Sweden)

    Erin J Adams

    2015-01-01

    Full Text Available The predominant population of γδ T cells in human blood express a T cell receptor (TCR composed of a Vγ9 (Vγ2 in an alternate nomenclature and Vδ2 domains. These cells came into the limelight when it was discovered they can respond to certain microbial infections and tumorigenic cells through the detection of small, pyrophosphate containing organic molecules collectively called phosphoantigens or pAgs. These molecules are intermediates in both eukaryotic and prokaryotic metabolic pathways. Chemical variants of these intermediates have been used in the clinic to treat a range of different cancers, however directed optimization of these molecules requires a full understanding of their mechanism of action on target cells. We and others have identified a subclass of butyrophilin-related molecules (BTN3A1-3 that are directly involved in pAg sensing in the target cell, leading to engagement and activation of the T cell through the TCR. Our data and that of others supports the pAg binding site to be the intracellular B30.2 domain of BTN3A1, which is the only isoform capable of mediating pAg-dependent stimulation of Vγ9Vδ2 T cells. Here we review the data demonstrating pAg binding to the B30.2 domain and our studies of the structural conformations of the BTN3A extracellular domains. Finally, we synthesize a model linking binding of pAg to the intracellular domain with T cell detection via the extracellular domains in an inside-out signaling mechanism of the type characterized first for integrin molecule signaling. We also explore the role of Vγ9Vδ2 TCR variability in the CDR3 γ and δ loops and how this may modulate Vγ9Vδ2 cells as a population in surveillance of human health and disease.

  7. Conservation of Fold and Topology of Functional Elements in Thiamin Pyrophosphate Enzymes

    Science.gov (United States)

    Dominiak, P.; Ciszak, E. M.

    2005-01-01

    Thiamin pyrophosphate (TPP)-dependent enzymes are a highly divergent family of proteins binding both TPP and metal ions. They perform decarboxylation-hydroxyaldehydes. Prior -ketoacids and of a common - (O=)C-C(OH)- fragment of to knowledge of three-dimensional structures of these enzmes, the GDGY25-30NN sequence was used to identify these enzymes. Subsequently, a number of structural studies on those enzymes revealed multi-subunit organization and the features of the two duplicate cofactor binding sites. Analyzing the structures of 44 structurally known enzymes, we found that the common structure of these enzymes is reduced to 180-220 amino acid long fragments of two PP and two PYR domains that form the [PP:PYR]2 binding center of two cofactor molecules. The structures of PP and PYR are arranged in a similar fold-sheet with triplets of helices on both sides.Dconsisting of a six-stranded Residues surrounding the cofactors are not strictly conserved, but they provide the same interatomic contacts required for the catalytic functions that these enzymes perform while maintaining interactive structural integrity. These structural and functional amino acids are topological counterparts located in the same positions of the conserved fold of sets of PP and PYR domains. Additional parallels include short fragments of sequences that link these amino acids to the fold and function. This report on the structural commonalities amongst TPP dependent enzymes is thought to contribute new approaches to annotation that may assist in advancing the functional proteomics of TPP dependent enzymes, and trace their complexity within evolutionary context.

  8. Pyrophosphate-Dependent ATP Formation from Acetyl Coenzyme A in Syntrophus aciditrophicus, a New Twist on ATP Formation

    Directory of Open Access Journals (Sweden)

    Kimberly L. James

    2016-08-01

    Full Text Available Syntrophus aciditrophicus is a model syntrophic bacterium that degrades key intermediates in anaerobic decomposition, such as benzoate, cyclohexane-1-carboxylate, and certain fatty acids, to acetate when grown with hydrogen-/formate-consuming microorganisms. ATP formation coupled to acetate production is the main source for energy conservation by S. aciditrophicus. However, the absence of homologs for phosphate acetyltransferase and acetate kinase in the genome of S. aciditrophicus leaves it unclear as to how ATP is formed, as most fermentative bacteria rely on these two enzymes to synthesize ATP from acetyl coenzyme A (CoA and phosphate. Here, we combine transcriptomic, proteomic, metabolite, and enzymatic approaches to show that S. aciditrophicus uses AMP-forming, acetyl-CoA synthetase (Acs1 for ATP synthesis from acetyl-CoA. acs1 mRNA and Acs1 were abundant in transcriptomes and proteomes, respectively, of S. aciditrophicus grown in pure culture and coculture. Cell extracts of S. aciditrophicus had low or undetectable acetate kinase and phosphate acetyltransferase activities but had high acetyl-CoA synthetase activity under all growth conditions tested. Both Acs1 purified from S. aciditrophicus and recombinantly produced Acs1 catalyzed ATP and acetate formation from acetyl-CoA, AMP, and pyrophosphate. High pyrophosphate levels and a high AMP-to-ATP ratio (5.9 ± 1.4 in S. aciditrophicus cells support the operation of Acs1 in the acetate-forming direction. Thus, S. aciditrophicus has a unique approach to conserve energy involving pyrophosphate, AMP, acetyl-CoA, and an AMP-forming, acetyl-CoA synthetase.

  9. UPLC-PDA-QTOFMS-guided isolation of prenylated xanthones and benzoylphloroglucinols from the leaves of Garcinia oblongifolia and their migration-inhibitory activity

    Science.gov (United States)

    Zhang, Hong; Dan, Zheng; Ding, Zhi-Jie; Lao, Yuan-Zhi; Tan, Hong-Sheng; Xu, Hong-Xi

    2016-10-01

    A UPLC-PDA-QTOFMS-guided isolation strategy was employed to screen and track potentially new compounds from Garcinia oblongifolia. As a result, two new prenylated xanthones, oblongixanthones D and E (1–2), six new prenylated benzoylphloroglucinol derivatives, oblongifolins V–Z (3–7) and oblongifolin AA (8), as well as a known compound oblongifolin L (9), were isolated from the EtOAc-soluble fraction of an acetone extract of the leaves of Garcinia oblongifolia guided by UPLC-PDA-QTOFMS analysis. The structures of the new compounds were elucidated by 1D- and 2D-NMR spectroscopic analysis and mass spectrometry. Experimental and calculated ECD spectra were used to determine the absolute configurations. The results of wound healing and transwell migration assay showed that oblongixanthones D (1), E (2), and oblongifolin L (9) have the ability to inhibit cancer cell migration in lower cytotoxic concentrations. Western blotting results showed that these compounds exhibited an anti-metastasis effect mainly through downregulating RAF protein levels. In addition, 2 and 9 could inhibit phospho-MEK and phospho-ERK at downstream. Moreover, 1, 2, and 9 could inhibit snail protein level, suggesting that they could regulate the EMT pathway.

  10. Preparative Isolation of Two Prenylated Biflavonoids from the Roots and Rhizomes of Sinopodophyllum emodi by Sephadex LH-20 Column and High-Speed Counter-Current Chromatography

    Directory of Open Access Journals (Sweden)

    Yan-Jun Sun

    2015-12-01

    Full Text Available Two prenylated biflavonoids, podoverines B–C, were isolated from the dried roots and rhizomes of Sinopodophyllum emodi using a Sephadex LH-20 column (SLHC and high-speed counter-current chromatography (HSCCC. The 95% ethanol extract was partitioned with ethyl acetate in water. Target compounds from the ethyl acetate fraction were further enriched and purified by the combined application of SLHC and HSCCC. n-Hexane–ethyl acetate–methanol–water (3.5:5:3.5:5, v/v was chosen as the two phase solvent system. The flow rate of mobile phase was optimized at 2.0 mL·min−1. Finally, under optimized conditions, 13.8 mg of podoverine B and 16.2 mg of podoverine C were obtained from 200 mg of the enriched sample. The purities of podoverines B and C were 98.62% and 99.05%, respectively, as determined by HPLC. For the first time, podoverins B and C were found in the genus Sinopodophyllum. Their structures were determined by spectroscopic methods (HR-ESI-MS, 1H-NMR, 13C-NMR, HSQC, HMBC. Their absolute configurations were elucidated by comparison of their experimental and calculated ECD spectra. The cytotoxic activities were evaluated against MCF-7 and HepG2 cell lines. The separation procedures proved to be practical and economical, especially for trace prenylated biflavonoids from traditional Chinese medicine.

  11. Preparative Isolation of Two Prenylated Biflavonoids from the Roots and Rhizomes of Sinopodophyllum emodi by Sephadex LH-20 Column and High-Speed Counter-Current Chromatography.

    Science.gov (United States)

    Sun, Yan-Jun; Pei, Li-Xin; Wang, Kai-Bo; Sun, Yin-Shi; Wang, Jun-Min; Zhang, Yan-Li; Gao, Mei-Ling; Ji, Bao-Yu

    2015-12-23

    Two prenylated biflavonoids, podoverines B-C, were isolated from the dried roots and rhizomes of Sinopodophyllum emodi using a Sephadex LH-20 column (SLHC) and high-speed counter-current chromatography (HSCCC). The 95% ethanol extract was partitioned with ethyl acetate in water. Target compounds from the ethyl acetate fraction were further enriched and purified by the combined application of SLHC and HSCCC. n-Hexane-ethyl acetate-methanol-water (3.5:5:3.5:5, v/v) was chosen as the two phase solvent system. The flow rate of mobile phase was optimized at 2.0 mL·min(-1). Finally, under optimized conditions, 13.8 mg of podoverine B and 16.2 mg of podoverine C were obtained from 200 mg of the enriched sample. The purities of podoverines B and C were 98.62% and 99.05%, respectively, as determined by HPLC. For the first time, podoverins B and C were found in the genus Sinopodophyllum. Their structures were determined by spectroscopic methods (HR-ESI-MS, ¹H-NMR, (13)C-NMR, HSQC, HMBC). Their absolute configurations were elucidated by comparison of their experimental and calculated ECD spectra. The cytotoxic activities were evaluated against MCF-7 and HepG2 cell lines. The separation procedures proved to be practical and economical, especially for trace prenylated biflavonoids from traditional Chinese medicine.

  12. UPLC-PDA-QTOFMS-guided isolation of prenylated xanthones and benzoylphloroglucinols from the leaves of Garcinia oblongifolia and their migration-inhibitory activity

    Science.gov (United States)

    Zhang, Hong; Dan, Zheng; Ding, Zhi-Jie; Lao, Yuan-Zhi; Tan, Hong-Sheng; Xu, Hong-Xi

    2016-01-01

    A UPLC-PDA-QTOFMS-guided isolation strategy was employed to screen and track potentially new compounds from Garcinia oblongifolia. As a result, two new prenylated xanthones, oblongixanthones D and E (1–2), six new prenylated benzoylphloroglucinol derivatives, oblongifolins V–Z (3–7) and oblongifolin AA (8), as well as a known compound oblongifolin L (9), were isolated from the EtOAc-soluble fraction of an acetone extract of the leaves of Garcinia oblongifolia guided by UPLC-PDA-QTOFMS analysis. The structures of the new compounds were elucidated by 1D- and 2D-NMR spectroscopic analysis and mass spectrometry. Experimental and calculated ECD spectra were used to determine the absolute configurations. The results of wound healing and transwell migration assay showed that oblongixanthones D (1), E (2), and oblongifolin L (9) have the ability to inhibit cancer cell migration in lower cytotoxic concentrations. Western blotting results showed that these compounds exhibited an anti-metastasis effect mainly through downregulating RAF protein levels. In addition, 2 and 9 could inhibit phospho-MEK and phospho-ERK at downstream. Moreover, 1, 2, and 9 could inhibit snail protein level, suggesting that they could regulate the EMT pathway. PMID:27767059

  13. Induced biosynthesis of resveratrol and the prenylated stilbenoids arachidin-1 and arachidin-3 in hairy root cultures of peanut: Effects of culture medium and growth stage.

    Science.gov (United States)

    Condori, Jose; Sivakumar, Ganapathy; Hubstenberger, John; Dolan, Maureen C; Sobolev, Victor S; Medina-Bolivar, Fabricio

    2010-05-01

    Previously, we have shown that hairy root cultures of peanut provide a controlled, sustainable and scalable production system that can be induced to produce stilbenoids. However to leverage peanut hairy roots to study the biosynthesis of this polyphenolic biosynthetic pathway, growing conditions and elicitation kinetics of these tissue cultures must be defined and understood. To this end, a new peanut cv. Hull hairy root (line 3) that produces resveratrol and its prenylated analogues arachidin-1 and arachidin-3 upon sodium acetate-mediated elicitation was established. Two culture media were compared for impact on root growth and stilbenoid biosynthesis/secretion. The levels of ammonium, nitrate, phosphate and residual sugars were monitored along growth and elicitation period. A modified MS (MSV) medium resulted in higher root biomass when compared to B5 medium. The stilbenoid profile after elicitation varied depending on the age of the culture (6, 9, 12, and 15-day old). After elicitation at day 9 (exponential growth in MSV medium), over 90% of the total resveratrol, arachidin-1 and arachidin-3 accumulated in the medium. Our studies demonstrate the benefits of the hairy root culture system to study the biosynthesis of stilbenoids including valuable prenylated polyphenolic compounds.

  14. Transcutaneous antigen delivery system

    Directory of Open Access Journals (Sweden)

    Mi-Young Lee

    2013-01-01

    Full Text Available Transcutaneous immunization refers to the topical applicationof antigens onto the epidermis. Transcutaneous immunizationtargeting the Langerhans cells of the skin has received muchattention due to its safe, needle-free, and noninvasive antigendelivery. The skin has important immunological functions withunique roles for antigen-presenting cells such as epidermalLangerhans cells and dermal dendritic cells. In recent years,novel vaccine delivery strategies have continually beendeveloped; however, transcutaneous immunization has not yetbeen fully exploited due to the penetration barrier representedby the stratum corneum, which inhibits the transport ofantigens and adjuvants. Herein we review recent achievementsin transcutaneous immunization, focusing on the variousstrategies for the enhancement of antigen delivery andvaccination efficacy. [BMB Reports 2013; 46(1: 17-24

  15. Inhibition of Clostridium botulinum 52A toxicity and protease activity by sodium acid pyrophosphate in media systems.

    OpenAIRE

    Wagner, M.K.; Busta, F. F.

    1985-01-01

    The effects of two pH levels (5.55 or 5.85) in combination with 0.4% sodium acid pyrophosphate (SAPP), NaH2PO4 X H2O, Na2HPO4 X 7H2O, or NaCl on the growth and toxicity of Clostridium botulinum 52A were studied. Absorbancy measurements at 630 nm, microscopic observations, and the mouse bioassay procedure were used to observe the effects. At pH 5.55 and 5.85 most control cultures exhibited toxicity when cell lysis began. Vegetative cell development was normal (4 micron long; 1 micron wide). SA...

  16. Gas-Phase Partial Oxidation of Lignin to Carboxylic Acids over Vanadium Pyrophosphate and Aluminum-Vanadium-Molybdenum.

    Science.gov (United States)

    Lotfi, Samira; Boffito, Daria C; Patience, Gregory S

    2015-10-26

    Lignin is a complex polymer that is a potential feedstock for aromatic compounds and carboxylic acids by cleaving the β-O-4 and 5-5' linkages. In this work, a syringe pump atomizes an alkaline solution of lignin into a catalytic fluidized bed operating above 600 K. The vanadium heterogeneous catalysts convert all the lignin into carboxylic acids (up to 25 % selectivity), coke, carbon oxides, and hydrogen. Aluminum-vanadium-molybdenum mostly produced lactic acid (together with formic acid, acrylic acid, and maleic anhydride), whereas the vanadium pyrophosphate catalyst produced more maleic anhydride.

  17. The peculiarities of electrochemical deposition and morphology of ZnMn alloy coatings obtained from pyrophosphate electrolyte

    Directory of Open Access Journals (Sweden)

    Bučko Mihael M.

    2011-01-01

    Full Text Available The first successful attempt to electrodeposit ZnMn alloy coatings from alkaline bath was made only a few years ago. In this kind of solution, potassium pyrophosphate (K4P2O7 serves both as a complexing agent and as the basic electrolyte. The aim of this work was to study the electrodeposition process and properties of ZnMn alloy coatings deposited from pyrophosphate solution, with a new kind of alkaline pyrophosphate bath. Namely, chloride salts were used as the source of metal ions and ascorbic acid was used as reducing agent. The composition of the plating solution was as follows: 1 mol dm-3 K4P2O7 + 0.017 mol dm-3 ascorbic acid + 0.05 mol dm-3 ZnCl2 + 0.05 mol dm-3 MnCl2•4H2O. Cathodic processes during the alloy electrodeposition were investigated using linear voltammetry. The influence of addition of small amounts of ascorbic acid on the cathodic processes was established. It was shown that this substance inhibits hydrogen evolution and increases the current efficiency of alloy deposition. The current efficiency in the plating bath examined was in the range of 25 and 30%, which was quite higher as compared to the results reported in the literature for electrodeposition of ZnMn alloy from pyrophosphate bath. Electrodeposition of ZnMn alloys was performed galvanostatically on steel panels, at current densities of 20120 mA cm-2. The coatings with the best appearance were obtained at current densities between 30 and 80 mA cm-2. The surface morphology studies, based on atomic force microscopy measurements, showed that morphology of the deposits is highly influenced by deposition current density. ZnMn coating deposited at 30 mA cm-2 was more compact and possessed more homogeneous structure (more uniform agglomeration size than the coating deposited at 80 mA cm-2. Such dependence of morphology on the current density could be explained by the high rate of hydrogen evolution reaction during the electrodeposition process.

  18. Defining function of lipopolysaccharide O-antigen ligase WaaL using chemoenzymatically synthesized substrates.

    Science.gov (United States)

    Han, Weiqing; Wu, Baolin; Li, Lei; Zhao, Guohui; Woodward, Robert; Pettit, Nicholas; Cai, Li; Thon, Vireak; Wang, Peng G

    2012-02-17

    The WaaL-mediated ligation of O-antigen onto the core region of the lipid A-core block is an important step in the lipopolysaccharide (LPS) biosynthetic pathway. Although the LPS biosynthesis has been largely characterized, only a limited amount of in vitro biochemical evidence has been established for the ligation reaction. Such limitations have primarily resulted from the barriers in purifying WaaL homologues and obtaining chemically defined substrates. Accordingly, we describe herein a chemical biology approach that enabled the reconstitution of this ligation reaction. The O-antigen repeating unit (O-unit) of Escherichia coli O86 was first enzymatically assembled via sequential enzymatic glycosylation of a chemically synthesized GalNAc-pyrophosphate-undecaprenyl precursor. Subsequent expression of WaaL through use of a chaperone co-expression system then enabled the demonstration of the in vitro ligation between the synthesized donor (O-unit-pyrophosphate-undecaprenyl) and the isolated lipid A-core acceptor. The previously reported ATP and divalent metal cation dependence were not observed using this system. Further analyses of other donor substrates revealed that WaaL possesses a highly relaxed specificity toward both the lipid moiety and the glycan moiety of the donor. Lastly, three conserved amino acid residues identified by sequence alignment were found essential for the WaaL activity. Taken together, the present work represents an in vitro systematic investigation of the WaaL function using a chemical biology approach, providing a system that could facilitate the elucidation of the mechanism of WaaL-catalyzed ligation reaction.

  19. 99mTc-pyrophosphate scintigraphy in the diagnosis of acute myocardial infarction. Myokardscintigrafi med 99mTc-pyrofosfat ved akutt hjerteinfarkt

    Energy Technology Data Exchange (ETDEWEB)

    Hole, T.; Rokkones, T. (Central Hospital in Moere og Romsdal, Aalesund (Norway))

    1990-02-01

    50 consecutive patients, hospitalized because of suspected myocardial infarction, were examined by 99mTc-pyrophosphate scintigraphy. The scans were interpreted blind by one of the authors. There were positive results in 17 of 21 patients with myocardial infarction (sensivity 0.81). However, scintigraphy was also positive in 13 patients with no evidence of myocardial infarction as asessed by ECG and enzyme criteria (specificity 0.55). It is concluded that 99mTc-pyrophosphate myocardial scintigraphy did not contribute valuable information to the routine diagnosis of myocardial infarction. 11 refs.; 3 tabs.

  20. Enhanced stability and local structure in biologically relevant amorphous materials containing pyrophosphate

    Energy Technology Data Exchange (ETDEWEB)

    Slater, Colin; Laurencin, Danielle; Burnell, Victoria; Smith, Mark E.; Grover, Liam M.; Hriljac, Joseph A.; Wright, Adrian J. (CNRS-UMR); (Birmingham UK)

    2012-10-25

    There is increasing evidence that amorphous inorganic materials play a key role in biomineralisation in many organisms, however the inherent instability of synthetic analogues in the absence of the complex in vivo matrix limits their study and clinical exploitation. To address this, we report here an approach that enhances long-term stability to >1 year of biologically relevant amorphous metal phosphates, in the absence of any complex stabilizers, by utilizing pyrophosphates (P{sub 2}O{sub 7}{sup 4-}); species themselves ubiquitous in vivo. Ambient temperature precipitation reactions were employed to synthesise amorphous Ca{sub 2}P{sub 2}O{sub 7}.nH{sub 2}O and Sr{sub 2}P{sub 2}O{sub 7}.nH{sub 2}O (3.8 < n < 4.2) and their stability and structure were investigated. Pair distribution functions (PDF) derived from synchrotron X-ray data indicated a lack of structural order beyond 8 {angstrom} in both phases, with this local order found to resemble crystalline analogues. Further studies, including {sup 1}H and {sup 31}P solid state NMR, suggest the unusually high stability of these purely inorganic amorphous phases is partly due to disorder in the P-O-P bond angles within the P{sub 2}O{sub 7} units, which impede crystallization, and to water molecules, which are involved in H-bonds of various strengths within the structures and hamper the formation of an ordered network. In situ high temperature powder X-ray diffraction data indicated that the amorphous nature of both phases surprisingly persisted to 450 C. Further NMR and TGA studies found that above ambient temperature some water molecules reacted with P{sub 2}O{sub 7} anions, leading to the hydrolysis of some P-O-P linkages and the formation of HPO{sub 4}{sup 2-} anions within the amorphous matrix. The latter anions then recombined into P{sub 2}O{sub 7} ions at higher temperatures prior to crystallization. Together, these findings provide important new materials with unexplored potential for enzyme

  1. The function of the three phosphoribosyl pyrophosphate synthetase (Prs) genes in hyphal growth and conidiation in Aspergillus nidulans.

    Science.gov (United States)

    Jiang, Ping; Wei, Wen-Fan; Zhong, Guo-Wei; Zhou, Xiao-Gang; Qiao, Wei-Ran; Fisher, Reinhard; Lu, Ling

    2017-02-01

    Phosphoribosyl pyrophosphate synthetase, which is encoded by the Prs gene, catalyses the reaction of ribose-5-phosphate and adenine ribonucleotide triphosphate (ATP) and has central importance in cellular metabolism. However, knowledge about how Prs family members function and contribute to total 5-phosphoribosyl-α-1-pyrophosphate (PRPP) synthetase activity is limited. In this study, we identified that the filamentous fungus Aspergillus nidulans genome contains three PRPP synthase-homologous genes (AnprsA, AnprsB and AnprsC), among which AnprsB and AnprsC but not AnprsA are auxotrophic genes. Transcriptional expression profiles revealed that the mRNA levels of AnprsA, AnprsB and AnprsC are dynamic during germination, hyphal growth and sporulation and that they all showed abundant expression during the vigorous hyphal growth time point. Inhibiting the expression of AnprsB or AnprsC in conditional strains produced more effects on the total PRPP synthetase activity than did inhibiting AnprsA, thus indicating that different AnPrs proteins are unequal in their contributions to Prs enzyme activity. In addition, the constitutive overexpression of AnprsA or AnprsC could significantly rescue the defective phenotype of the AnprsB-absent strain, suggesting that the function of AnprsB is not a specific consequence of this auxotrophic gene but instead comes from the contribution of Prs proteins to PRPP synthetase activity.

  2. The function of the three phosphoribosyl-pyrophosphate synthetase (Prs) genes in hyphal growth and conidiation in Aspergillus nidulans.

    Science.gov (United States)

    Jiang, Ping; Wei, Wen-Fan; Zhong, Guo-Wei; Zhou, Xiao-Gang; Qiao, Wei-Ran; Lu, Ling

    2017-01-12

    Phosphoribosyl pyrophosphate synthetase, which is encoded by the Prs gene, catalyzes the reaction of ribose-5-phosphate and adenine ribonucleotide triphosphate (ATP) and has central importance in cellular metabolism. However, knowledge about how Prs family members function and contribute to total PRPP synthetase activity is limited. In this study, we identified that the filamentous fungus Aspergillus nidulans genome contains three 5-phosphoribosyl-α-1-pyrophosphate (PRPP) synthase-homologous genes (AnprsA, B, and C), among which AnprsB and AnprsC but not AnprsA are auxotrophic genes. Transcriptional expression profiles revealed that the mRNA levels of AnprsA, B and C are dynamic during germination, hyphal growth and sporulation and that they all showed abundant expression during the vigorous hyphal growth time-point. Inhibiting the expression of AnprsB or AnprsC in conditional strains produced more effects on the total PRPP synthetase activity than did inhibiting AnprsA, thus indicating that different AnPrs proteins are unequal in their contributions to Prs enzyme activity. In addition, the constitutive overexpression of AnprsA or AnprsC could significantly rescue the defective phenotype of the AnprsB-absent strain, suggesting that the function of AnprsB is not a specific consequence of this auxotrophic gene but instead comes from the contribution of Prs proteins to PRPP synthetase activity.

  3. Engineering of geranylgeranyl pyrophosphate synthase levels and physiological conditions for enhanced carotenoid and astaxanthin synthesis in Xanthophyllomyces dendrorhous.

    Science.gov (United States)

    Breitenbach, Jürgen; Visser, Hans; Verdoes, Jan C; van Ooyen, Albert J J; Sandmann, Gerhard

    2011-04-01

    The basidiomycetous yeast, Xanthophyllomyces dendrorhous, is one of the very few organisms which can be used for biological production of the carotenoid astaxanthin. crtE cDNA has been cloned from this fungus for engineering of the terpenoid pathway. The function of its gene product as a geranylgeranyl pyrophosphate synthase was established. X. dendrorhous was transformed with the crtE cDNA to divert metabolite flow from the sterol pathway towards carotenoid biosynthesis. Transformants were obtained with increased levels of geranylgeranyl pyrophosphate synthase leading to higher carotenoid levels including astaxanthin. Physiological conditions for maximum carotenoid synthesis for wild type and the CrtE transformant were dim light and extra air supply of the shaking culture. These conditions and the transformation with crtE had additive effects and resulted in an 8-fold higher astaxanthin formation as compared to the initial wild type culture without illumination and extra air supply yielding 451 μg/g dry wt within 4 days of growth.

  4. Genetic analysis and enzyme activity suggest the existence of more than one minimal functional unit capable of synthesizing phosphoribosyl pyrophosphate in Saccharomyces cerevisiae

    DEFF Research Database (Denmark)

    Hernando, Yolanda; Carter, Andrew T.; Parr, Adrian;

    1999-01-01

    The PRS gene family in Saccharomyces cerevisiae consists of five genes each capable of encoding a 5-phosphoribosyl-1(α)-pyrophosphate synthetase polypeptide. To gain insight into the functional organization of this gene family we have constructed a collection of strains containing all possible co...

  5. Effect of pH, sodium chloride and sodium pyrophosphate on the termal resistance of Escherichia coli O157:H7 in ground beef

    Science.gov (United States)

    Response to the Letter to the Editor: We have received with great satisfaction that our article “Modelling the effect of pH, sodium chloride and sodium pyrophosphate on the thermal resistance of Escherichia coli O157:H7 in ground beef” (Food Research International, 69:289-304; 2015) has awaken inte...

  6. Efficient regeneration of NADPH in a 3-enzyme cascade reaction by in situ generation of glucose 6-phosphate from glucose and pyrophosphate

    NARCIS (Netherlands)

    Hartog, A.F.; van Herk, T.; Wever, R.

    2011-01-01

    We report here a promising method to regenerate NADPH (nicotinamide adenine dinucleotide phosphate) using the intermediate formation of glucose 6-phosphate (G6P) from glucose and pyrophosphate (PPi) catalyzed by the acid phosphatase from Shigella flexneri (PhoN-Sf). The G6P formed is used in turn by

  7. Design and structure-activity relationships of potent and selective inhibitors of undecaprenyl pyrophosphate synthase (UPPS): tetramic, tetronic acids and dihydropyridin-2-ones.

    Science.gov (United States)

    Peukert, Stefan; Sun, Yingchuan; Zhang, Rui; Hurley, Brian; Sabio, Mike; Shen, Xiaoyu; Gray, Christen; Dzink-Fox, JoAnn; Tao, Jianshi; Cebula, Regina; Wattanasin, Sompong

    2008-03-15

    Based on a pharmacophore hypothesis substituted tetramic and tetronic acid 3-carboxamides as well as dihydropyridin-2-one-3-carboxamides were investigated as inhibitors of undecaprenyl pyrophosphate synthase (UPPS) for use as novel antimicrobial agents. Synthesis and structure-activity relationship patterns for this class of compounds are discussed. Selectivity data and antibacterial activities for selected compounds are provided.

  8. Farnesylated and methylated KRAS4b: high yield production of protein suitable for biophysical studies of prenylated protein-lipid interactions.

    Science.gov (United States)

    Gillette, William K; Esposito, Dominic; Abreu Blanco, Maria; Alexander, Patrick; Bindu, Lakshman; Bittner, Cammi; Chertov, Oleg; Frank, Peter H; Grose, Carissa; Jones, Jane E; Meng, Zhaojing; Perkins, Shelley; Van, Que; Ghirlando, Rodolfo; Fivash, Matthew; Nissley, Dwight V; McCormick, Frank; Holderfield, Matthew; Stephen, Andrew G

    2015-11-02

    Prenylated proteins play key roles in several human diseases including cancer, atherosclerosis and Alzheimer's disease. KRAS4b, which is frequently mutated in pancreatic, colon and lung cancers, is processed by farnesylation, proteolytic cleavage and carboxymethylation at the C-terminus. Plasma membrane localization of KRAS4b requires this processing as does KRAS4b-dependent RAF kinase activation. Previous attempts to produce modified KRAS have relied on protein engineering approaches or in vitro farnesylation of bacterially expressed KRAS protein. The proteins produced by these methods do not accurately replicate the mature KRAS protein found in mammalian cells and the protein yield is typically low. We describe a protocol that yields 5-10 mg/L highly purified, farnesylated, and methylated KRAS4b from insect cells. Farnesylated and methylated KRAS4b is fully active in hydrolyzing GTP, binds RAF-RBD on lipid Nanodiscs and interacts with the known farnesyl-binding protein PDEδ.

  9. A comparative study on the metabolism of Epimedium koreanum Nakai-prenylated flavonoids in rats by an intestinal enzyme (lactase phlorizin hydrolase) and intestinal flora.

    Science.gov (United States)

    Zhou, Jing; Chen, Yan; Wang, Ying; Gao, Xia; Qu, Ding; Liu, Congyan

    2013-12-24

    The aim of this study was to compare the significance of the intestinal hydrolysis of prenylated flavonoids in Herba Epimedii by an intestinal enzyme and flora. Flavonoids were incubated at 37 °C with rat intestinal enzyme and intestinal flora. HPLC-UV was used to calculate the metabolic rates of the parent drug in the incubation and LC/MS/MS was used to determine the chemical structures of metabolites generated by different flavonoid glycosides. Rates of flavonoid metabolism by rat intestinal enzyme were quicker than those of intestinal flora. The sequence of intestinal flora metabolic rates was icariin>epimedin B>epimedin A>epimedin C>baohuoside I, whereas the order of intestinal enzyme metabolic rates was icariin>epimedin A>epimedin C>epimedin B>baohuoside I. Meanwhile, the LC/MS/MS graphs showed that icariin produced three products, epimedin A/B/C had four and baohuoside I yielded one product in incubations of both intestinal enzyme and flora, which were more than the results of HPLC-UV due to the fact LC/MS/MS has lower detectability and higher sensitivity. Moreover, the outcomes indicated that the rate of metabolization of flavonoids by intestinal enzyme were faster than those of intestinal flora, which was consistent with the HPLC-UV results. In conclusion, the metabolic pathways of the same components by intestinal flora and enzyme were the same. What's more, an intestinal enzyme such as lactase phlorizin hydrolase exhibited a more significant metabolic role in prenylated flavonoids of Herba Epimedi compared with intestinal flora.

  10. Quantitative and qualitative characteristics of cell wall components and prenyl lipids in the leaves of Tilia x euchlora trees growing under salt stress.

    Science.gov (United States)

    Milewska-Hendel, Anna; Baczewska, Aneta H; Sala, Katarzyna; Dmuchowski, Wojciech; Brągoszewska, Paulina; Gozdowski, Dariusz; Jozwiak, Adam; Chojnacki, Tadeusz; Swiezewska, Ewa; Kurczynska, Ewa

    2017-01-01

    The study was focused on assessing the presence of arabinogalactan proteins (AGPs) and pectins within the cell walls as well as prenyl lipids, sodium and chlorine content in leaves of Tilia x euchlora trees. The leaves that were analyzed were collected from trees with and without signs of damage that were all growing in the same salt stress conditions. The reason for undertaking these investigations was the observations over many years that indicated that there are trees that present a healthy appearance and trees that have visible symptoms of decay in the same habitat. Leaf samples were collected from trees growing in the median strip between roadways that have been intensively salted during the winter season for many years. The sodium content was determined using atomic spectrophotometry, chloride using potentiometric titration and poly-isoprenoids using HPLC/UV. AGPs and pectins were determined using immunohistochemistry methods. The immunohistochemical analysis showed that rhamnogalacturonans I (RG-I) and homogalacturonans were differentially distributed in leaves from healthy trees in contrast to leaves from injured trees. In the case of AGPs, the most visible difference was the presence of the JIM16 epitope. Chemical analyses of sodium and chloride showed that in the leaves from injured trees, the level of these ions was higher than in the leaves from healthy trees. Based on chromatographic analysis, four poly-isoprenoid alcohols were identified in the leaves of T. x euchlora. The levels of these lipids were higher in the leaves from healthy trees. The results suggest that the differences that were detected in the apoplast and symplasm may be part of the defensive strategy of T. x euchlora trees to salt stress, which rely on changes in the chemical composition of the cell wall with respect to the pectic and AGP epitopes and an increased synthesis of prenyl lipids.

  11. Quantitative and qualitative characteristics of cell wall components and prenyl lipids in the leaves of Tilia x euchlora trees growing under salt stress

    Science.gov (United States)

    Milewska-Hendel, Anna; Baczewska, Aneta H.; Sala, Katarzyna; Dmuchowski, Wojciech; Brągoszewska, Paulina; Gozdowski, Dariusz; Jozwiak, Adam; Chojnacki, Tadeusz; Swiezewska, Ewa; Kurczynska, Ewa

    2017-01-01

    The study was focused on assessing the presence of arabinogalactan proteins (AGPs) and pectins within the cell walls as well as prenyl lipids, sodium and chlorine content in leaves of Tilia x euchlora trees. The leaves that were analyzed were collected from trees with and without signs of damage that were all growing in the same salt stress conditions. The reason for undertaking these investigations was the observations over many years that indicated that there are trees that present a healthy appearance and trees that have visible symptoms of decay in the same habitat. Leaf samples were collected from trees growing in the median strip between roadways that have been intensively salted during the winter season for many years. The sodium content was determined using atomic spectrophotometry, chloride using potentiometric titration and poly-isoprenoids using HPLC/UV. AGPs and pectins were determined using immunohistochemistry methods. The immunohistochemical analysis showed that rhamnogalacturonans I (RG-I) and homogalacturonans were differentially distributed in leaves from healthy trees in contrast to leaves from injured trees. In the case of AGPs, the most visible difference was the presence of the JIM16 epitope. Chemical analyses of sodium and chloride showed that in the leaves from injured trees, the level of these ions was higher than in the leaves from healthy trees. Based on chromatographic analysis, four poly-isoprenoid alcohols were identified in the leaves of T. x euchlora. The levels of these lipids were higher in the leaves from healthy trees. The results suggest that the differences that were detected in the apoplast and symplasm may be part of the defensive strategy of T. x euchlora trees to salt stress, which rely on changes in the chemical composition of the cell wall with respect to the pectic and AGP epitopes and an increased synthesis of prenyl lipids. PMID:28234963

  12. Effect of tetrasodium pyrophosphate on the physicochemical properties of yogurt gels.

    Science.gov (United States)

    Ozcan, T; Lucey, J A; Horne, D S

    2008-12-01

    The effect of tetrasodium pyrophosphate (TSPP) on the properties of yogurt gels was investigated. Various concentrations (0.05 to 0.2%) of TSPP were added to preheated (85 degrees C for 30 min) reconstituted skim milk, which was readjusted to pH 6.50. Milk was inoculated with 2% starter culture and incubated at 42 degrees C until the pH reached 4.6. Acid-base buffering profiles of milk and total and soluble calcium levels were measured. Turbidity measurements were used to indicate changes in casein dispersion. Storage modulus (G') and loss tangent (LT) values of yogurts were monitored during fermentation using dynamic oscillatory rheology. Large deformation properties of gels were also measured. Microstructural properties of yogurt were observed using fluorescence microscopy. The addition of TSPP resulted in the disappearance of the buffering peak during acid titration at pH approximately 5.1 that is due to the solubilization of colloidal calcium phosphate (CCP), and a new peak was observed at lower pH values (pH 4.0-4.5). The buffering peak at pH 6.0 during base titration virtually disappeared with addition of TSPP and a new peak appeared at pH approximately 4.8. The addition of TSPP reduced the soluble Ca content of milk and increased casein-bound Ca values. The addition of up to 0.125% TSPP resulted in a reduction in turbidity because of micelle dispersion but at 0.15%, turbidity increased and these samples exhibited a time-dependent increase in turbidity because of aggregation of casein particles. Gels made with 0.20% TSPP were very weak and had a very high gelation pH (6.35), probably due to complete dispersion of the micelle structure in this sample. The LT value of gels at pH 5.1 decreased with an increase in TSPP concentration, probably due to the loss of CCP with the addition of TSPP. The G' values at pH 4.6 of gels made with or=0.125% TSPP significantly decreased G' values. The addition of 0.05 to 0.125% TSPP to milk resulted in a reduction in the yield

  13. Effect of pyrophosphate ions on the conversion of calcium-lithium-borate glass to hydroxyapatite in aqueous phosphate solution.

    Science.gov (United States)

    Fu, Hailuo; Rahaman, Mohamed N; Day, Delbert E; Huang, Wenhai

    2010-10-01

    The conversion of glass to a hydroxyapatite (HA) material in an aqueous phosphate solution is used as an indication of the bioactive potential of the glass, as well as a low temperature route for preparing biologically useful materials. In this work, the effect of varying concentrations of pyrophosphate ions in the phosphate solution on the conversion of a calcium-lithium-borate glass to HA was investigated. Particles of the glass (150-355 μm) were immersed for up to 28 days in 0.25 M K(2)HPO(4) solution containing 0-0.1 M K(4)P(2)O(7). The kinetics of degradation of the glass particles and their conversion to HA were monitored by measuring the weight loss of the particles and the ionic concentration of the solution. The structure and composition of the conversion products were analyzed using X-ray diffraction, scanning electron microscopy, and Fourier transform infrared spectroscopy. For K(4)P(2)O(7) concentrations of up to 0.01 M, the glass particles converted to HA, but the time for complete conversion increased from 2 days (no K(4)P(2)O(7)) to 10 days (0.01 M K(4)P(2)O(7)). When the K(4)P(2)O(7) concentration was increased to 0.1 M, the product consisted of an amorphous calcium phosphate material, which eventually crystallized to a pyrophosphate product (predominantly K(2)CaP(2)O(7) and Ca(2)P(2)O(7)). The consequences of the results for the formation of HA materials and devices by the glass conversion route are discussed.

  14. Functional significance of four successive glycine residues in the pyrophosphate binding loop of fungal 6-oxopurine phosphoribosyltransferases.

    Science.gov (United States)

    Moynié, Lucile; Giraud, Marie-France; Breton, Annick; Boissier, Fanny; Daignan-Fornier, Bertrand; Dautant, Alain

    2012-08-01

    Hypoxanthine-guanine phosphoribosyltransferase (HGPRT) is a key enzyme of the purine recycling pathway that catalyzes the conversion of 5-phospho-ribosyl-α-1-pyrophosphate and guanine or hypoxanthine to guanosine monophosphate (GMP) or inosine monophosphate (IMP), respectively, and pyrophosphate (PPi). We report the first crystal structure of a fungal 6-oxopurine phosphoribosyltransferase, the Saccharomyces cerevisiae HGPRT (Sc-HGPRT) in complex with GMP. The crystal structures of full length protein with (WT1) or without (WT2) sulfate that mimics the phosphate group in the PPi binding site were solved by molecular replacement using the structure of a truncated version (Δ7) solved beforehand by multiwavelength anomalous diffusion. Sc-HGPRT is a dimer and adopts the overall structure of class I phosphoribosyltransferases (PRTs) with a smaller hood domain and a short two-stranded parallel β-sheet linking the N- to the C-terminal end. The catalytic loops in WT1 and WT2 are in an open form while in Δ7, due to an inter-subunit disulfide bridge, the catalytic loop is in either an open or closed form. The closure is concomitant with a peptide plane flipping in the PPi binding loop. Moreover, owing the flexibility of a GGGG motif conserved in fungi, all the peptide bonds of the phosphate binding loop are in trans conformation whereas in nonfungal 6-oxopurine PRTs, one cis-peptide bond is required for phosphate binding. Mutations affecting the enzyme activity or the previously characterized feedback inhibition by GMP are located at the nucleotide binding site and the dimer interface. Copyright © 2012 The Protein Society.

  15. Use of genomics to identify bacterial undecaprenyl pyrophosphate synthetase: cloning, expression, and characterization of the essential uppS gene.

    Science.gov (United States)

    Apfel, C M; Takács, B; Fountoulakis, M; Stieger, M; Keck, W

    1999-01-01

    The prenyltransferase undecaprenyl pyrophosphate synthetase (di-trans,poly-cis-decaprenylcistransferase; EC 2.5.1.31) was purified from the soluble fraction of Escherichia coli by TSK-DEAE, ceramic hydroxyapatite, TSK-ether, Superdex 200, and heparin-Actigel chromatography. The protein was labeled with the photolabile analogue of the farnesyl pyrophosphate analogue (E, E)-[1-3H]-(2-diazo-3-trifluoropropionyloxy)geranyl diphosphate and was detected on a sodium dodecyl sulfate-polyacrylamide gel as a protein with an apparent molecular mass of 29 kDa. This protein band was cut out from the gel, trypsin digested, and subjected to matrix-assisted laser desorption ionization mass spectrometric analysis. Comparison of the experimental data with computer-simulated trypsin digest data for all E. coli proteins yielded a single match with a protein of unassigned function (SWISS-PROT Q47675; YAES_ECOLI). Sequences with strong similarity indicative of homology to this protein were identified in 25 bacterial species, in Saccharomyces cerevisiae, and in Caenorhabditis elegans. The homologous genes (uppS) were cloned from E. coli, Haemophilus influenzae, and Streptococcus pneumoniae, expressed in E. coli as amino-terminal His-tagged fusion proteins, and purified over a Ni2+ affinity column. An untagged version of the E. coli uppS gene was also cloned and expressed, and the protein purified in two chromatographic steps. We were able to detect Upp synthetase activity for all purified enzymes. Further, biochemical characterization revealed no differences between the recombinant untagged E. coli Upp synthetase and the three His-tagged fusion proteins. All enzymes were absolutely Triton X-100 and MgCl2 dependent. With the use of a regulatable gene disruption system, we demonstrated that uppS is essential for growth in S. pneumoniae R6.

  16. Cancer testis antigen and immunotherapy

    Directory of Open Access Journals (Sweden)

    Krishnadas DK

    2013-04-01

    Full Text Available Deepa Kolaseri Krishnadas, Fanqi Bai, Kenneth G Lucas Department of Pediatrics, Division of Hematology/Oncology, University of Louisville, KY, USA Abstract: The identification of cancer testis (CT antigens has been an important advance in determining potential targets for cancer immunotherapy. Multiple previous studies have shown that CT antigen vaccines, using both peptides and dendritic cell vaccines, can elicit clinical and immunologic responses in several different tumors. This review details the expression of melanoma antigen family A, 1 (MAGE-A1, melanoma antigen family A, 3 (MAGE-A3, and New York esophageal squamous cell carcinoma-1 (NY-ESO-1 in various malignancies, and presents our current understanding of CT antigen based immunotherapy. Keywords: cancer testis antigens, immunotherapy, vaccine

  17. Purification, molecular cloning, and expression of 2-hydroxyphytanoyl- CoA lyase, a peroxisomal thiamine pyrophosphate-dependent enzyme that catalyzes the carbon-carbon bond cleavage during à-oxidation of 3- methyl-branched fatty acids

    CERN Document Server

    Foulon, V; Croes, K; Waelkens, E

    1999-01-01

    Purification, molecular cloning, and expression of 2-hydroxyphytanoyl- CoA lyase, a peroxisomal thiamine pyrophosphate-dependent enzyme that catalyzes the carbon-carbon bond cleavage during à-oxidation of 3- methyl-branched fatty acids

  18. Antigen antibody interactions

    CERN Document Server

    DeLisi, Charles

    1976-01-01

    1. 1 Organization of the Immune System One of the most important survival mechanisms of vertebrates is their ability to recognize and respond to the onslaught of pathogenic microbes to which they are conti- ously exposed. The collection of host cells and molecules involved in this recognition­ 12 response function constitutes its immune system. In man, it comprises about 10 cells 20 (lymphocytes) and 10 molecules (immunoglobulins). Its ontogenic development is c- strained by the requirement that it be capable of responding to an almost limitless variety of molecular configurations on foreign substances, while simultaneously remaining inert to those on self components. It has thus evolved to discriminate, with exquisite precision, between molecular patterns. The foreign substances which induce a response, called antigens, are typically large molecules such as proteins and polysaccharides. The portions of these with which immunoglobulins interact are called epitopes or determinants. A typical protein epitope m...

  19. Trypanosoma cruzi: circulating antigens

    Directory of Open Access Journals (Sweden)

    V. Bongertz

    1981-03-01

    Full Text Available Circulating antigens were detected in sera of mice experimentally infected with a high close of Trypanosoma cruzi by reaction with sera from chronically infected mice. The immunodiffusion reaction between homologous acute and chronic sera produced four precipitation lines. By reaction with chronic mouse serum, circulating antingens were detected in sera from heavily infected hamsters, dogs, rabbits and in sera from chagasic patients. A reaction was also found in urine from acutely infected mice and dogs. Trypanosoma cruzi exoantigen was detected in trypanosome culture medium and in the supernatant of infected cell cultures. Attempts to isolate the antigens are described.Antígenos circulantes foram detectados em soros de camundongos infectados experimentalmente com elevadas doses de Trypanosoma cruzi pela reação com soros obtidos de camundongos em fase crônica de infecção. A reação de imunodifusão entre soros homólogos agudo e crônico produziu quatro linhas de precipitação. Por reação com soro crônico de camundongo antígenos circulantes foram detectados em soros de crícetos, cães e coelhos infectados com doses elevadas de Trypanosoma cruzi e em soros de pacientes chagásicos. Uma reação foi também observada com urina de camundongos e cães infectados de forma aguda. Exoantígeno de Trypanosoma cruzi foi detectado em meio de cultura de tripanosomas e em sobrenadantes de culturas de células infectadas. Tentativas de isolamento dos antigenos são descritas.

  20. Thermal lens study of thermo-optical properties and concentration quenching of Er{sup 3+}-doped lead pyrophosphate-based glasses

    Energy Technology Data Exchange (ETDEWEB)

    Santos, C. C. [Departamento de Fisica, CCET, Universidade Federal do Maranhao, 65085-580 Sao Luis-MA (Brazil); Rocha, U.; Vermelho, M. V. D.; Jacinto, C. [Grupo de Fotonica e Fluidos Complexos, Instituto de Fisica, Universidade Federal de Alagoas, 57072-970 Maceio, AL (Brazil); Guedes, I. [Departamento de Fisica, Universidade Federal do Ceara, Campus do PICI, Caixa Postal 6030, 60455-760 Fortaleza, CE (Brazil); Boatner, L. A. [ORNL Center for Radiation Detection Materials and Systems and ORNL Materials Science and Technology Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831-6044 (United States)

    2012-06-15

    In this work, we have used the thermal lens technique combined with conventional spectroscopy to characterize the thermo-optical properties of Er{sup 3+}-doped lead pyrophosphate-based glasses. More precisely, we have investigated and quantified experimentally the fluorescence quantum efficiencies of the Er{sup 3+} levels, and we describe the role of concentration quenching effects. The fluorescence quantum efficiency of the {sup 4}I{sub 13/2} level is very high when compared to other phosphate glasses, while that of the green-coupled levels is very small. Other important photonic materials parameters, such as the thermal diffusivity and temperature coefficient of the optical path length change, were obtained and compared with those of other glass systems. The cumulative results obtained here for the Er-doped lead pyrophosphate glass show that this material is a good candidate for photonic applications with a characteristic Er{sup 3+} infrared emission around 1550 nm.

  1. X-ray characteristics of wrists in calcium pyrophosphate crystal deposition disease. Is pseudogout a major cause of scapholunate advanced collapse?

    Science.gov (United States)

    Taniguchi, Y; Yoshida, M; Tamaki, T

    1997-10-01

    Deposition of calcium pyrophosphate dihydrate (CPPD) crystals has been considered to be a cause of scapholunate advanced collapse (SLAC) wrist. The aim of this study was to look at X-ray changes in wrist joints affected by CPPD crystal deposition disease and to determine whether crystal deposition is a cause of SLAC wrist. A total of 150 wrists of 78 patients with CPPD crystal deposition disease were examined. In our population of Japanese patients with CPPD crystal deposition disease, the incidence of SLAC wrist was very low, and no case of Stage III SLAC wrist was found. We therefore conclude that SLAC wrist is not a radiographic characteristic of CPPD crystal deposition disease and that pyrophosphate crystal deposition cannot be a major cause of SLAC wrist.

  2. Radioimmunoassays of hidden viral antigens

    Energy Technology Data Exchange (ETDEWEB)

    Neurath, A.R. (Lindsley F. Kimbell Research Inst., New York, NY); Strick, N.; Baker, L.; Krugman, S.

    1982-07-01

    Antigens corresponding to infectious agents may be present in biological specimens only in a cryptic form bound to antibodies and, thus, may elude detection. We describe a solid-phase technique for separation of antigens from antibodies. Immune complexes are precipitated from serum by polyethylene glycol, dissociated with NaSCN, and adsorbed onto nitrocellulose or polystyrene supports. Antigens remain topographically separated from antibodies after removal of NaSCN and can be detected with radiolabeled antibodies. Genomes from viruses immobilized on nitrocellulose can be identified by nucleic acid hybridization. Nanogram quantities of sequestered hepatitis B surface and core antigens and picogram amounts of hepatitis B virus DNA were detected. Antibody-bound adenovirus, herpesvirus, and measles virus antigens were discerned by the procedure.

  3. Radioimmunoassays of hidden viral antigens.

    Science.gov (United States)

    Neurath, A R; Strick, N; Baker, L; Krugman, S

    1982-01-01

    Antigens corresponding to infectious agents may be present in biological specimens only in a cryptic form bound to antibodies and, thus, may elude detection. We describe a solid phase technique for separation of antigens from antibodies. Immune complexes are precipitated from serum by polyethylene glycol, dissociated with NaSCN, and adsorbed onto nitrocellulose or polystyrene supports. Antigens remain topographically separated from antibodies after removal of NaSCN and can be detected with radiolabeled antibodies. Genomes from viruses immobilized on nitrocellulose can be identified by nucleic acid hybridization. Nanogram quantities of sequestered hepatitis B surface and core antigens and picogram amounts of hepatitis B virus DNA were detected. Antibody-bond adenovirus, herpesvirus, and measles virus antigens were discerned by the procedure. Images PMID:6956871

  4. Antigenic Variation in Bacterial Pathogens.

    Science.gov (United States)

    Palmer, Guy H; Bankhead, Troy; Seifert, H Steven

    2016-02-01

    Antigenic variation is a strategy used by a broad diversity of microbial pathogens to persist within the mammalian host. Whereas viruses make use of a minimal proofreading capacity combined with large amounts of progeny to use random mutation for variant generation, antigenically variant bacteria have evolved mechanisms which use a stable genome, which aids in protecting the fitness of the progeny. Here, three well-characterized and highly antigenically variant bacterial pathogens are discussed: Anaplasma, Borrelia, and Neisseria. These three pathogens display a variety of mechanisms used to create the structural and antigenic variation needed for immune escape and long-term persistence. Intrahost antigenic variation is the focus; however, the role of these immune escape mechanisms at the population level is also presented.

  5. Preparation and Bioactivity Properties of a Novel Composite Membrane of Fructose Mediated β-Tricalcium Pyrophosphate/(Polyethylene Glycol/Chitosan) for Guided Tissue Regeneration

    OpenAIRE

    Jian-Wen Wang; Min-Hsiung Hon; Yi-Ming Kuo; Mei-Hui Chung

    2015-01-01

    A novel composite membrane of β-tricalcium pyrophosphate (β-TCP) and fructose- (F-) mediated chitosan/poly(ethylene glycol) (CS/PEG) was prepared by thermally induced phase separation technique. The prepared composite membranes were characterized using scanning electron microscopy (SEM) and X-ray diffraction (XRD). The mechanical property, swelling, degradation, and cytotoxicity of the composite membranes were evaluated in vitro with respect to its potential for use as biodegradable guided ti...

  6. Novel strategy for the facile enrichment of isopentenyl pyrophosphate in rat plasma via Ti(4+) -immobilized polydopamine@Fe3 O4 core-shell microspheres.

    Science.gov (United States)

    Xu, Chen; Yu, Yingjia; Ling, Li; Sun, Xueni; Li, Yan; Duan, Gengli

    2017-05-01

    In this paper, a facile extraction strategy is reported for the analysis of isopentenyl pyrophosphate, a key isoprenoid, based on magnetic core-shell microspheres with Ti(4+) ion exterior walls coupled with liquid chromatography and tandem mass spectrometry. Because of their excellent hydrophilicity and biological compatibility, the polydopamine@Fe3 O4 -Ti(4+) microspheres display ideal isopentenyl pyrophosphate extraction efficiency. The technique includes three steps: sample loading, nonphosphate washing, and phosphate elution. Moreover, the microspheres can be regenerated by thorough washing with a specific solvent and can be reused multiple times. The liquid chromatography with tandem mass spectrometry separation was performed on a Welch Ultimate® XB-C18 column with a total chromatographic analysis time of 5 min; the analytical recovery was 98.52%. The proposed method was used to determine the isopentenyl pyrophosphate concentration in rat plasma samples collected from the Shanghai Chest Hospital. The results indicate the prospective value of the as-made microspheres for the sensitive and selective enrichment of phosphate compounds in complicated matrices. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. COLONOSCOPY AND CARCINOEMBRYONIC ANTIGEN VARIATIONS

    Directory of Open Access Journals (Sweden)

    Rita G SOUSA

    2014-03-01

    Full Text Available Context Colonoscopy is essential for synchronous and metachronous cancer detection. Carcinoembryonic antigen is a colorectal cancer tumor marker, important as a follow-up tool in patients with previous colorectal cancer. False-positive carcinoembryonic antigen elevation results in multiples exams and in patient anxiety. In literature, there is reference to transient carcinoembryonic antigen increase with colonoscopy. Objective To evaluate the influence of bowel preparation and colonoscopy in carcinoembryonic antigen blood levels. Methods We prospectively studied subjects that underwent routine colonoscopy in our institution. Blood samples were collected (1 before bowel cleaning, (2 before colonoscopy and (3 immediately after colonoscopy. Blood carcinoembryonic antigen levels were determined by “Sandwich” immunoassay. The statistical methods used were the paired t-test and ANOVA. Results Thirty-seven patients (22M/15F were included; age range 28-84 (mean 56 years. Mean carcinoembryonic antigen values were 1.9, 2 and 1.8 for (1, (2 and (3, respectively. An increase in value (2 compared with (1 was observed in 20/37 patients (P = 0.018, mainly in younger patients and in patients requiring more endoluminal interventions. In 29/37 patients, the CEA value decreased from (2 to (3 (P = 1.3x10-7. Conclusions A trend for carcinoembryonic antigen increase after bowel cleaning was observed, especially in younger patients and in patients with more endoluminal interventions, but without clinical meaning.

  8. Toxic and antifeedant activities of prenylated flavonoids isolated from Tephrosia apollinea L. against three major coleopteran pests of stored grains with reference to their structure-activity relationship.

    Science.gov (United States)

    Nenaah, Gomah E

    2014-01-01

    Four prenylated flavonoids, isoglabratephrin, (+)-glabratephrin, tephroapollin-F and lanceolatin-A, were isolated from Tephrosia apollinea L. and tested against three stored grain insects. Using the filter paper bioassay, compounds showed adulticidal activity against Sitophilus oryzae (L), Rhyzopertha dominica (F) and Tribolium castaneum (Herbst) at concentrations of 0.875, 1.75 and 3.5 mg mL(- 1). At 3.5 mg mL(- 1), tephroapollin-F was the most toxic (78.6%, 64.6% and 60.7% mortality was recorded after 10 days exposure of S. oryzae, R. dominica and T. castaneum, respectively). The F1 progeny production of insects was affected after parental exposure to flavonoids, where S. oryzae was the most susceptible. A nutritional bioassay, employing a flour disc and test concentrations of 0.65, 1.3 and 2.6 mg g(- 1), revealed a significant reduction in the relative growth rate, relative consumption rate and efficiency of conversion of ingested food by all insects. The structure-activity relationship among the tested flavonoids was discussed.

  9. Xanthohumol, a main prenylated chalcone from hops, reduces liver damage and modulates oxidative reaction and apoptosis in hepatitis C virus infected Tupaia belangeri.

    Science.gov (United States)

    Yang, Mingbo; Li, Na; Li, Fang; Zhu, Qianqian; Liu, Xi; Han, Qunying; Wang, Yawen; Chen, Yanping; Zeng, Xiaoyan; Lv, Yi; Zhang, Pingping; Yang, Cuiling; Liu, Zhengwen

    2013-08-01

    Hepatitis C virus (HCV) infection in Tupaia belangeri (Tupaia) represents an important model of HCV infection. Xanthohumol (XN), a major prenylated chalcone from hops, has various biological activities including hepatopreventive and anti-viral activities. In this study, Tupaias infected with HCV RNA positive serum were used to evaluate the effects of XN on liver damage, oxidative reaction, apoptosis and viral protein expression in liver tissues. The Tupaias inoculated with HCV positive serum had elevated serum aminotransferase levels and inflammation, especially hepatic steatosis, and HCV core protein expression in liver tissue. In the animals inoculated with HCV positive serum, XN significantly decreased aminotransferase levels, histological activity index, hepatic steatosis score and transforming growth factor β1 expression in liver tissue compared with the animals without XN intervention. XN reduced HCV core protein expression in liver tissue compared with those without XN intervention but the difference was not significant. XN significantly decreased malondialdehyde, potentiated superoxide dismutase and glutathione peroxidase, reduced Bax expression, promoted Bcl-xL and inhibited caspase 3 activity in liver tissues compared with the animals without XN intervention. These results indicate that XN may effectively improve hepatic inflammation, steatosis and fibrosis induced by HCV in Tupaias primarily through inhibition of oxidative reaction and regulation of apoptosis and possible suppression of hepatic stellate cell activation. The anti-HCV potential of XN needs further investigation.

  10. Prenylated flavonoids from the stems and leaves of Desmodium caudatum and evaluation of their inhibitory activity against the film-forming growth of Zygosaccharomyces rouxii F51.

    Science.gov (United States)

    Sasaki, Hisako; Shibata, Hirofumi; Imabayashi, Kiyoshi; Takaishi, Yoshihisa; Kashiwada, Yoshiki

    2014-07-09

    In order to provide scientific evidence for the relationship between the traditional usage, stems and leaves of Desmodium caudatum being used for protecting miso from spoilage, and its Japanese name (miso-naoshi), phytochemical study on the stems and leaves of this plant was carried out. Seven new prenylated flavonoids (1-3, 15-18), together with 19 known compounds (4-14, 19-26), were isolated, and the structures of new compounds were elucidated by extensive spectroscopic analyses. The minimum inhibitory concentrations (MICs) of 28 flavonoids, including 17 compounds (1, 2, 4, 5, 7-14, 20-22, 24, 25) isolated in this study and 11 flavonoids (27-37) previously isolated from the roots of this plant, against the film-forming yeast of Zygosaccharomyces rouxii F51 were determined. Fifteen compounds (2, 4, 5, 11, 12, 14, 21, 22, 25, 27, 28, 32-35) inhibited the film-forming growth of Z. rouxii F51 (MIC values, 7.8-62.5 μg/mL), among which 2",2"-dimethylpyran-(5",6":7,8)-5,2'-dihydroxy-4'-methoxy-(2R,3R)-dihydroflavonol (11) demonstrated potent inhibitory activity with an MIC value of 7.8 μg/mL.

  11. Comparative inhibitory effect of prenylated coumarins, ferulenol and ferprenin, contained in the 'poisonous chemotype' of Ferula communis on mammal liver microsomal VKORC1 activity.

    Science.gov (United States)

    Louvet, Marie-Sophie; Gault, Gilbert; Lefebvre, Sébastien; Popowycz, Florence; Boulven, Manon; Besse, Stéphane; Benoit, Etienne; Lattard, Virginie; Grancher, Denis

    2015-10-01

    Two distinguishable chemotypes of Ferula communis have been described: the 'nonpoisonous' chemotype, containing as main constituents the daucane esters; and the 'poisonous' chemotype containing prenylated coumarins, such as ferulenol and ferprenin. Ferulenol and ferprenin are 4-oxygenated molecules such as dicoumarol and warfarin, the first developed antivitamin K molecules. Antivitamin K molecules specifically inhibit VKORC1, an enzyme essential for recycling vitamin K. This latest is involved in the activation of clotting factors II, VII, IX, X. The inhibiting effect of ferulenol on VKORC1 was shown in rat, but not for species exposed to F. communis while in vivo studies suggest differences between animal susceptibility to ferulenol. The inhibiting effect of ferprenin on VKORC1 was never demonstrated. The aim of this study was to compare the inhibiting effect of both compounds on VKORC1 of different species exposed to F. communis. Vitamin K epoxide activity was evaluated for each species from liver microsomes and inhibiting effect of ferulenol and ferprenin was characterized. Ferulenol and ferprenin were shown to be able to inhibit VKORC1 from all analyzed species. Nevertheless, susceptibility to ferulenol and ferprenin presented differences between species, suggesting a different susceptibility to 'poisonous' chemotypes of F. communis.

  12. Coenzyme Q10 supplementation rescues renal disease in Pdss2kd/kd mice with mutations in prenyl diphosphate synthase subunit 2.

    Science.gov (United States)

    Saiki, Ryoichi; Lunceford, Adam L; Shi, Yuchen; Marbois, Beth; King, Rhonda; Pachuski, Justin; Kawamukai, Makoto; Gasser, David L; Clarke, Catherine F

    2008-11-01

    Homozygous mice carrying kd (kidney disease) mutations in the gene encoding prenyl diphosphate synthase subunit 2 (Pdss2kd/kd) develop interstitial nephritis and eventually die from end-stage renal disease. The PDSS2 polypeptide in concert with PDSS1 synthesizes the polyisoprenyl tail of coenzyme Q (Q or ubiquinone), a lipid quinone required for mitochondrial respiratory electron transport. We have shown that a deficiency in Q content is evident in Pdss2kd/kd mouse kidney lipid extracts by 40 days of age and thus precedes the onset of proteinuria and kidney disease by several weeks. The presence of the kd (V117M) mutation in PDSS2 does not prevent its association with PDSS1. However, heterologous expression of the kd mutant form of PDSS2 together with PDSS1 in Escherichia coli recapitulates the Q deficiency observed in the Pdss2kd/kd mouse. Dietary supplementation with Q10 provides a dramatic rescue of both proteinuria and interstitial nephritis in the Pdss2kd/kd mutant mice. The results presented suggest that Q may be acting as a potent lipid-soluble antioxidant, rather than by boosting kidney mitochondrial respiration. Such Q10 supplementation may have profound and beneficial effects in treatment of certain forms of focal segmental glomerulosclerosis that mirror the renal disease of the Pdss2kd/kd mouse.

  13. Neuroprotective effect of prenylated arylbenzofuran and flavonoids from morus alba fruits on glutamate-induced oxidative injury in HT22 hippocampal cells.

    Science.gov (United States)

    Seo, Kyeong-Hwa; Lee, Dae-Young; Jeong, Rak-Hun; Lee, Dong-Sung; Kim, Young-Eon; Hong, Eock-Kee; Kim, Youn-Chul; Baek, Nam-In

    2015-04-01

    A prenylated arylbenzofuran and six flavonoids were isolated from the fruits of Morus alba L. through silica gel, octadecyl silica gel, and Diaion HP-20 column chromatography. Based on the nuclear magnetic resonance, mass spectrometry, and infrared spectroscopic data, the chemical structures of the compounds were determined to be artoindonesianin O (1), isobavachalcone (2), morachalcone A (3), quercetin (4), astragalin (5), isoquercetin (6), and rutin (7). The isolated compounds were evaluated for protection of HT22-immortalized hippocampal cells against glutamate-induced oxidative stress. Compounds 1 and 3 exhibited protective effects with EC(50) values of 19.7±1.2 and 35.5±2.1 μM, respectively. The major compounds 1-3 and 7 were quantified using liquid chromatography/mass spectrometry analysis and were determined to be 1.88±2.1, 1.90±1.8, 0.78±1.5, and 37.29±2.2 mg/kg, respectively, in the ethanol extract of M. alba L. fruits.

  14. Heterologous expression of chloroplast-localized geranylgeranyl pyrophosphate synthase confers fast plant growth, early flowering and increased seed yield.

    Science.gov (United States)

    Tata, Sandeep Kumar; Jung, Jihye; Kim, Yoon-Ha; Choi, Jun Young; Jung, Ji-Yul; Lee, In-Jung; Shin, Jeong Sheop; Ryu, Stephen Beungtae

    2016-01-01

    Geranylgeranyl pyrophosphate synthase (GGPS) is a key enzyme for a structurally diverse class of isoprenoid biosynthetic metabolites including gibberellins, carotenoids, chlorophylls and rubber. We expressed a chloroplast-targeted GGPS isolated from sunflower (Helianthus annuus) under control of the cauliflower mosaic virus 35S promoter in tobacco (Nicotiana tabacum). The resulting transgenic tobacco plants expressing heterologous GGPS showed remarkably enhanced growth (an increase in shoot and root biomass and height), early flowering, increased number of seed pods and greater seed yield compared with that of GUS-transgenic lines (control) or wild-type plants. The gibberellin levels in HaGGPS-transgenic plants were higher than those in control plants, indicating that the observed phenotype may result from increased gibberellin content. However, in HaGGPS-transformant tobacco plants, we did not observe the phenotypic defects such as reduced chlorophyll content and greater petiole and stalk length, which were previously reported for transgenic plants expressing gibberellin biosynthetic genes. Fast plant growth was also observed in HaGGPS-expressing Arabidopsis and dandelion plants. The results of this study suggest that GGPS expression in crop plants may yield desirable agronomic traits, including enhanced growth of shoots and roots, early flowering, greater numbers of seed pods and/or higher seed yield. This research has potential applications for fast production of plant biomass that provides commercially valuable biomaterials or bioenergy. © 2015 Korea Research Institute of Bioscience & Biotechnology. Plant Biotechnology Journal published by John Wiley & Sons Ltd and Society for Experimental Biology, Association of Applied Biologists.

  15. Technetium stannous pyrophosphate myocardial scintigrams in the recognition of myocardial infarction in patients undergoing coronary artery revascularization

    Energy Technology Data Exchange (ETDEWEB)

    Platt, M.R.; Parkey, R.W.; Willerson, J.T.; Bonte, F.J.; Shapiro, W.; Sugg, W.L.

    1976-04-01

    Myocardial imaging using technetium 99m stannous pyrophosphate (/sup 99m/Tc-PYP) has been utilized preoperatively and three to five days postoperatively to detect myocardial infarction in 48 patients undergoing aortocoronary bypass grafting, including 7 having valve replacement (5 aortic, 2 mitral) in addition to revascularization. In the total group of patients operated on there were 3 deaths (6%). Preoperatively, 26 patients had unstable angina and 10 had severe left main coronary artery disease. Eleven of the 48 (23%) were women. ECG and enzyme-proved infarctions occurred in 6 of the 48 patients (12%), but the addition of /sup 99m/Tc-PYP myocardial imaging demonstrated scintigraphic evidence of infarction in 15 patients (31%), including 2 who died in the operating room. The /sup 99m/Tc-PYP myocardial imaging technique, which has proved safe, simple, and relatively inexpensive in these patients, suggests that the incidence of infarction after coronary bypass operations is somewhat higher than has been previously recognized from just ECG and enzyme changes. This technique also has been of value in helping to exclude myocardial infarction in difficult clinical situations such as postoperative arrhythmias and the postpericardiotomy syndrome.

  16. Synthesis of p-Hydroxybenzaldehyde by Liquid-phase Catalytic Oxidation of p-Cresol over PVDF Modified Cobalt Pyrophosphate

    Institute of Scientific and Technical Information of China (English)

    ZHANG Yi-bo; WANG De-qiang; MIAO Zhen-zhen; PAN Xi-qiang; ZHANG Zhen-dong; YANG Xiang-guang

    2013-01-01

    The influence of the wettability of a catalyst on the performance of the liquid phase oxidation of p-cresol was investigated.It was found that the surface hydrophobicity of a catalyst,which can be changed by modification with various loadings of polyvinylidene fluoride(PVDF),has a promotion effect on the catalytic performance.At the same time,the reaction parameters such as oxygen pressure,molar ratio of NaOH to p-cresol,reaction temperature and time on the catalytic performance in the liquid-phase oxidation of p-cresol were optimized.As a result,10%(mass fraction) PVDF modified cobalt pyrophosphate gave the highest conversion of 94.2% of p-cresol with a selectivity of 94.4% for p-hydroxybenzaldehyde at 348 K and a molar ratio of 4:1 of NaOH/p-cresol and an oxygen pressure of 1.0 MPa for 3 h.

  17. Calcification in calcium pyrophosphate dihydrate (CPPD) crystalline deposits in the knee: anatomic, radiographic, MR imaging, and histologic study in cadavers

    Energy Technology Data Exchange (ETDEWEB)

    Abreu, M.; Chung, C.B.; Lima, J.E. de; Trudell, D. [Department of Musculoskeletal Radiology, University of California, San Diego, VA San Diego Healthcare System, 3350 La Jolla Village Drive, CA 92162, San Diego (United States); Johnson, K.; Terkeltaub, R.; Resnick, D. [Department of Rheumatology, University of California, San Diego, VA San Diego Healthcare System, 3350 La Jolla Village Drive, CA 92162, San Diego (United States); Pe, S. [University of California, San Diego, VA San Diego Healthcare System, 3350 La Jolla Village Drive, CA 92162, San Diego (United States)

    2004-07-01

    To demonstrate and determine the frequency and location of calcification within cadaveric knees with or without calcification typical of calcium pyrophosphate dihydrate (CPPD), utilizing histologic, radiographic and MR imaging techniques. Ten cadaveric knees of elderly individuals that demonstrated no radiographic evidence of prior surgery or trauma were studied with MR imaging and subsequently sectioned in planes corresponding to those obtained with MR imaging. The slices were imaged with high-resolution radiography. Two musculoskeletal radiologists correlated the anatomic, MR and radiographic findings. Three of the knees, which did not demonstrate calcifications, were utilized as controls. Histologic sections were obtained from four knees that contained calcifications and from the three controls, and analyzed with special histologic stains that demonstrate phosphorus and calcium. Radiographic imaging and histologic analysis demonstrated widespread CPPD crystal deposition in four of the 10 knee specimens (40%). MR imaging demonstrated some calcifications only within the articular cartilage of the femoral condyles in three of the four (75%) specimens that had CPPD deposits. In all four specimens radiographs and histologic analysis were more sensitive than MR imaging. Histologic analysis demonstrated no evidence of CPPD crystals in the control specimens. MR imaging is insensitive to the presence of CPPD deposits in the knee, even when such deposits are widespread. Our study suggests that the sensitivity of MR imaging was significantly better in detecting CPPD deposits in the hyaline cartilage of the femoral condyles when compared with other internal structures, even when such structures contained a higher amount of calcification. (orig.)

  18. Diff-Quik® staining method for detection and identification of monosodium urate and calcium pyrophosphate crystals in synovial fluids

    Directory of Open Access Journals (Sweden)

    M. Hammoud

    2011-09-01

    Full Text Available The aim of this study was to evaluate whether DQ could prove useful to identify monosodium urate (MSU and calcium pyrophosphate dehydrate (CPPD crystals on permanent mounted stained slides. To this end, we studied 27 synovial fluid (SF samples obtained from the knees of patients with the pseudogout (n=21 and acute gouty arthritis (n=6. Wet analysis for crystal detection and identification was performed within one hour of joint aspiration. In addition, we studied 16 inflammatory synovial effusions obtained from patients with knee arthritis not induced by crystals. For each SF, DQ stained slides were analyzed by 2 experienced doctors in SF analysis. The observers were blinded to the type of crystal present in the SF. Each slide was analyzed by compensated polarized and transmitted light microscopy. SF was considered positive if intracellular and/or extracellular crystals were clearly identified. In addition, the observers were asked to identify the type of the crystals using compensated polarized light microscopy. Sensitivity, specificity, accuracy, positive predictive value (PPV, and negative predictive value (NPV of the DQ staining method were determined. 51 true positive and 28 true negative specimens were correctly classified (39 CPPD samples, 12 MSU samples, and 28 samples of crystals-unrelated arthropathies. All MSU specimens were correctly diagnosed.

  19. Sugar-mediated chitosan/poly(ethylene glycol)-beta-dicalcium pyrophosphate composite: mechanical and microstructural properties.

    Science.gov (United States)

    Wang, Jian-Wen; Hon, Min-Hsiung

    2003-02-01

    The microstructural and mechanical properties of sugar-mediated chitosan/poly(ethylene glycol)-based scaffolds and composites, which are composed of beta-dicalcium pyrophosphate (beta-DCP) and sugar-mediated scaffolds, were investigated. All of the scaffolds were prepared by various freeze-drying protocols. The differences in the freeze-drying process of the sugar-mediated chitosan/poly(ethylene glycol) scaffold for three types of sugar (sucrose, glucose, and D-fructose) were determined by scanning electron microscopic observation, water retention, density, and porosity analyses. The sugar-mediated scaffolds prepared by scheme I of the freeze-drying process show large pores, poorly connective interlayers, and disintegrated inner structures, different from the small pores and well-connective channel structures as shown in the scheme II freeze-drying process. The key factors for controlling pore structure and size in the scheme I freeze-drying process were formulation and composition, but for the scheme II freeze-drying process, the key factor was freeze protocol. The composite scaffolds were macroporous, and the microstructure changed considerably with added beta-DCP content. The incorporation of beta-DCP granules caused a significant enhancement of compressive modulus and yield strength. The increased mechanical strength may be attributable not only to the physical complexation between the sugar-mediated scaffold and beta-DCP, but also the chemical reaction to apatite formed on the cell wall.

  20. Influence of the radioactive concentration of the in vitro stability of Tc-99m(Sn-pyrophosphate

    Directory of Open Access Journals (Sweden)

    JURIJ L. VUCINA

    1999-05-01

    Full Text Available The in vitro stability of 99mTc(Sn-pyrophosphate solution was examined in dependence on the preparation conditions of the samples, the radioactive concentration of 99mTc in the kit and the time elapsed after labeling. The samples without any protection are highly unstable. The formation of 99mTc-pertechnetate does not depend on the radioactive concentration. Nitrogen purging provides protection in the case of low radioactive concentrations (37 MBq 99mTc/ml but exhibits no effect at higher concentrations. The best stabilization was achieved by using ascorbic acid. A concentration of 60 µg/ml keeps the content of 99mTc-pertechnetate below 1% during six hours after labeling, even in solutions of high readioactive concentrations (740-814 MBq/ml. Gentisic acid is less effective. Concentrations about ten times higher than required using ascorbic acid are needed to keep the content of 99mTc-pertechnetate below 5% during six hours.

  1. Extracellular Matrix Proteins, Alkaline Phosphatase and Pyrophosphate as Molecular Determinants of Bone, Tooth, Kidney and Vascular Calcification

    Science.gov (United States)

    McKee, Marc D.

    2008-09-01

    Progress in biomineralization research in recent years has identified, characterized and described functions for key noncollagenous extracellular matrix proteins regulating crystal growth in the skeleton and dentition. Some of these same proteins expressed in soft tissues undergoing pathologic calcification also inhibit ectopic crystal growth. In addition to extracellular matrix proteins regulating matrix mineralization, the enzyme tissue-nonspecific alkaline phosphatase—which is highly expressed by cells in mineralized tissues—cleaves pyrophosphate, an anionic small-molecule inhibitor of mineralization. Together with the required mineral ion availability necessary for crystal growth, these molecular determinants appear to function in limiting the spread of pathologic calcification seen in soft tissues such as blood vessels and kidneys. Osteopontin, in particular, is a potent calcification inhibitor that accumulates in mineralized tissues and in calcified deposits during vascular calcification and nephrolithiasis/urolithiasis. Additional research is required to establish the exact temporal sequence in which the molecular determinants of pathologic calcification appear relative to mineral crystal growth in different tissues, and to establish their relationship (if any) to the activation of osteogenic differentiation programs.

  2. Ferric pyrophosphate citrate administered via dialysate reduces erythropoiesis-stimulating agent use and maintains hemoglobin in hemodialysis patients

    Science.gov (United States)

    Gupta, Ajay; Lin, Vivian; Guss, Carrie; Pratt, Raymond; Ikizler, T Alp; Besarab, Anatole

    2015-01-01

    Ferric pyrophosphate citrate (FPC) is a water-soluble iron salt administered via dialysate to supply iron directly to transferrin. The PRIME study tested whether treatment with FPC could reduce prescribed erythropoiesis-stimulating agent (ESA) use and maintain hemoglobin in hemodialysis patients. This 9-month, randomized, placebo-controlled, double-blind, multicenter clinical study included 103 patients undergoing hemodialysis 3–4 times weekly. The FPC group received dialysate containing 2 μmol/l of iron. The placebo group received standard dialysate. A blinded central anemia management group facilitated ESA dose adjustments. Intravenous iron was administered according to the approved indication when ferritin levels fell below 200 μg/l. The primary end point was the percentage change from baseline in prescribed ESA dose at end of treatment. Secondary end points included intravenous iron use and safety. At the end of treatment, there was a significant 35% reduction in prescribed ESA dose in FPC-treated patients compared with placebo. The FPC patients used 51% less intravenous iron than placebo. Adverse and serious adverse events were similar in both groups. Thus, FPC delivered via dialysate significantly reduces the prescribed ESA dose and the amount of intravenous iron needed to maintain hemoglobin in chronic hemodialysis patients. PMID:26154926

  3. Electrical conductivity of titanium pyrophosphate between 100 and 400 °C: effect of sintering temperature and phosphorus content

    DEFF Research Database (Denmark)

    Lapina, Alberto; Chatzichristodoulou, Christodoulos; Hallinder, Jonathan;

    2014-01-01

    The synthesis of titanium pyrophosphate is carried out, and the material is sintered at different temperatures between 370 and 970 °C. Yttrium is added during the synthesis to act as acceptor dopant, but it is mainly present in the material in secondary phases. The conductivity is studied...... systematically as a function of sintering temperature, pH2O, pO2, and temperature (100–400 °C). Loss of phosphorus upon sintering above 580–600 °C is confirmed by energy dispersive spectroscopy and combined thermogravimetry and mass spectrometry. The conductivity decreases with increasing sintering temperature...... and decreasing phosphorus content. The highest conductivity is 5.3 × 10−4 S cm−1 at 140 °C in wet air (pH2O = 0.22 atm) after sintering at 370 °C. The conductivity is higher in wet atmospheres than in dry atmospheres. The proton conduction mechanism is discussed, and the conductivity is attributed...

  4. Effect of methylprednisolone upon technetium-99m pyrophosphate assessment of myocardial necrosis in the canine countershock model

    Energy Technology Data Exchange (ETDEWEB)

    Schneider, R.M.; Hayslett, J.P.; Downing, S.E.; Berger, H.J.; Donabedian, R.K.; Zaret, B.L.

    1977-12-01

    RRepeat DC countershock reproducibly results in myocardial necrosis in dogs. In this model, myocardial technetium-/sup 99m/ pyrophosphate (PYP) uptake correlates linearly with tissue creatine kinase depletion (r = -0.83). The effect of pretreatment with methylprednisolone (MP) was studied with PYP in 25 dogs. In myocardium damaged by countershock, 12 MP dogs had higher tissue radioactivity sample:normal (S:N) ratios than control (P < 0.05), suggesting increased tissue injury. However, by several other measures of tissue damage, the two groups did not differ. MP-elevated PYP S:N ratios were explained by reduced PYP activity in normal myocardium of MP dogs. Further experiments in 21 dogs revealed that renal PYP clearance, which correlated with glomerular filtration rate (GFR) as measured by creatinine clearance, was increased in MP dogs, resulting in accelerated urinary excretion of PYP (46.9 +- 3.6 vs 35.8 +- 2.4 percent injected dose in one hour, P < 0.01), and reduced blood PYP. Thus, MP does not modify countershock-induced myocardial injury. However, by increasing GFR, MP increased PYP excretion, resulting in lowered blood and normal zone myocardial PYP, thereby spuriously affecting myocardial PYP tissue uptake data.

  5. Cellular delivery and photochemical release of a caged inositol-pyrophosphate induces PH-domain translocation in cellulo.

    Science.gov (United States)

    Pavlovic, Igor; Thakor, Divyeshsinh T; Vargas, Jessica R; McKinlay, Colin J; Hauke, Sebastian; Anstaett, Philipp; Camuña, Rafael C; Bigler, Laurent; Gasser, Gilles; Schultz, Carsten; Wender, Paul A; Jessen, Henning J

    2016-02-04

    Inositol pyrophosphates, such as diphospho-myo-inositol pentakisphosphates (InsP7), are an important family of signalling molecules, implicated in many cellular processes and therapeutic indications including insulin secretion, glucose homeostasis and weight gain. To understand their cellular functions, chemical tools such as photocaged analogues for their real-time modulation in cells are required. Here we describe a concise, modular synthesis of InsP7 and caged InsP7. The caged molecule is stable and releases InsP7 only on irradiation. While photocaged InsP7 does not enter cells, its cellular uptake is achieved using nanoparticles formed by association with a guanidinium-rich molecular transporter. This novel synthesis and unprecedented polyphosphate delivery strategy enable the first studies required to understand InsP7 signalling in cells with controlled spatiotemporal resolution. It is shown herein that cytoplasmic photouncaging of InsP7 leads to translocation of the PH-domain of Akt, an important signalling-node kinase involved in glucose homeostasis, from the membrane into the cytoplasm.

  6. The prevalence of monosodium urate and calcium pyrophosphate crystals in synovial fluid from wrist and finger joints.

    Science.gov (United States)

    Galozzi, Paola; Oliviero, Francesca; Frallonardo, Paola; Favero, Marta; Hoxha, Ariela; Scanu, Anna; Lorenzin, Mariagrazia; Ortolan, Augusta; Punzi, Leonardo; Ramonda, Roberta

    2016-03-01

    The aim of this study was to assess the frequency of monosodium urate (MSU) and calcium pyrophosphate (CPP) crystals in synovial fluids (SFs) aspirated from wrist and finger joints of patients with previously diagnosed joint diseases. We reviewed the results of SF analysis of 1593 samples and identified 126 patients with effusions in the small joints of the hands and wrists. We reported from patients' medical files data about sex, age, diagnosis, disease duration and the microscopic SF results. The prevalence of CPP crystals in SF was 85.71% in CPP-crystals arthritis (CPP-CA), 19.35% in rheumatoid arthritis (RA), 13.89% in osteoarthritis (OA) and 0% in psoriatic arthritis (PsA), spondyloarthritis (SpA), gout and miscellanea. The prevalence of MSU crystals in SF was 83.3% in gout, 10% in PsA, 2.8% in OA and 0% in RA, SpA, miscellanea and CPP-CA. Consistent with previously reported data concerning the big joints, microcrystals can be frequently found also in the small joints of patients with previous diagnosis. The finding underlines the importance of analyzing SF from the hand and wrist joints in the attempt to identify comorbidities associated with the presence of crystals and to develop targeted treatment strategies.

  7. Alterations of the [59Fe]ferric citrate biodistribution in hyperferremic mice after the administration of pyrophosphate and desferrioxamine.

    Science.gov (United States)

    Sawas-Dimopoulou, C; Soulpi, C

    1983-02-01

    One of the most efficient anions in enhancing the ability of desferrioxamine (DFO) to remove iron from transferrin in vitro has been shown to be pyrophosphate (PYP). To evaluate the in vivo effect of PYP in hyperferremic mice, the biodistribution of [59Fe]ferric citrate was studied after the i.p. administration of: 1) only saline in the control animals; 2) an aqueous solution of tetrasodium diphosphate (PYP; 40 gm/2 g of b.wt.); 3) desferral (DFO; 12 mg/20 g of b.wt.); and 4) PYP + DFO at the respective dosages shown above. The radioactivity in each organ, blood, urine and feces was measured and referred to as percentage of the injected dose. PYP administered alone acted as a weaker chelator of iron than DFO. The combined administration of DFO and PYP contributed more than DFO or PYP separately, to the increase of urinary excretion of 59Fe and to the significant decrease of the radioiron concentration in liver (.01 less than P less than .05). The above induced changes are not, however, the additive result of the separate effect of DFO and PYP. That observation would suggest that DFO + PYP combined in a unique treatment, interact with iron through a common reaction pathway and that PYP plays in vivo a synergistic role in that interaction. The kind of iron with which DFO + PYP interacts is then suggested to be the transferrin-bound iron located in extracellular spaces of tissues.

  8. Alterations of the (/sup 59/Fe)ferric citrate biodistribution in hyperferremic mice after the administration of pyrophosphate and desferrioxamine

    Energy Technology Data Exchange (ETDEWEB)

    Sawas-Dimopoulou, C.; Soulpi, C.

    1983-02-01

    One of the most efficient anions in enhancing the ability of desferrioxamine (DFO) to remove iron from transferrin in vitro has been shown to be pyrophosphate (PYP). To evaluate the in vivo effect of PYP in hyperferremic mice, the biodistribution of (/sup 59/Fe)ferric citrate was studied after the i.p. administration of: 1) only saline in the control animals; 2) an aqueous solution of tetrasodium diphosphate (PYP; 40 gm/2 g of b.wt.); 3) desferral (DFO; 12 mg/20 g of b.wt.); and 4) PYP + DFO at the respective dosages shown above. The radioactivity in each organ, blood, urine and feces was measured and referred to as percentage of the injected dose. PYP administered alone acted as a weaker chelator of iron than DFO. The combined administration of DFO and PYP contributed more than DFO or PYP separately, to the increase of urinary excretion of /sup 59/Fe and to the significant decrease of the radioiron concentration in liver (.01 less than P less than .05). The above induced changes are not, however, the additive result of the separate effect of DFO and PYP. That observation would suggest that DFO + PYP combined in a unique treatment, interact with iron through a common reaction pathway and that PYP plays in vivo a synergistic role in that interaction. The kind of iron with which DFO + PYP interacts is then suggested to be the transferrin-bound iron located in extracellular spaces of tissues.

  9. Alterations of the (/sup 59/Fe)ferric citrate biodistribution in hyperferremic mice after the administration of pyrophosphate and desferrioxamine

    Energy Technology Data Exchange (ETDEWEB)

    Sawas-Dimopoulou, C.; Soulpi, C.

    1983-02-01

    One of the most efficient anions in enhancing the ability of desferrioxamine (DFO) to remove iron from transferrin in vitro has been shown to be pyrophosphate (PYP). To evaluate the in vivo effect of PYP in hyperferremic mice, the biodistribution of (/sup 59/Fe)ferric citrate was studied after the i.p. administration of: 1) only saline in the control animals; 2) an aqueous solution of tetrasodium diphosphate; 3) desferral; and 4) PYP + DFO. The radioactivity in each organ, blood, urine and feces was measured and referred to as percentage of the injected dose. PYP administered alone acted as a weaker chelator of iron than DFO. The combined administration of DFO and PYP contributed more than DFO or PYP separately, to the increase of urinary excretion of 59Fe and to the significant decrease of the radioiron concentration in liver. The above induced changes are not, however, the additive result of the separate effect of DFO and PYP. That observation would suggest that DFO + PYP combined in a unique treatment, interact with iron through a common reaction pathway and that PYP plays in vivo a synergistic role in that interaction. The kind of iron with which DFO + PYP interacts is then suggested to be the transferrin-bound iron located in extracellular spaces of tissues.

  10. Oncogenic cancer/testis antigens

    DEFF Research Database (Denmark)

    Gjerstorff, Morten F; Andersen, Mads H; Ditzel, Henrik J

    2015-01-01

    Recent developments have set the stage for immunotherapy as a supplement to conventional cancer treatment. Consequently, a significant effort is required to further improve efficacy and specificity, particularly the identification of optimal therapeutic targets for clinical testing. Cancer....../testis antigens are immunogenic, highly cancer-specific, and frequently expressed in various types of cancer, which make them promising candidate targets for cancer immunotherapy, including cancer vaccination and adoptive T-cell transfer with chimeric T-cell receptors. Our current understanding of tumor...... immunology and immune escape suggests that targeting oncogenic antigens may be beneficial, meaning that identification of cancer/testis antigens with oncogenic properties is of high priority. Recent work from our lab and others provide evidence that many cancer/testis antigens, in fact, have oncogenic...

  11. Epicutaneous sensitization with protein antigen

    Directory of Open Access Journals (Sweden)

    I-Lin Liu

    2012-12-01

    Full Text Available In the past few decades there has been a progressive understanding that epicutaneous sensitization with protein antigen is an important sensitization route in patients with atopic dermatitis. A murine protein-patch model has been established, and an abundance of data has been obtained from experiments using this model. This review discusses the characteristics of epicutaneous sensitization with protein antigen, the induced immune responses, the underlying mechanisms, and the therapeutic potential.

  12. Evaluation of host inflammatory responses of β-tricalcium phosphate bioceramics caused by calcium pyrophosphate impurity using a subcutaneous model.

    Science.gov (United States)

    Lin, Kaili; Yuan, Wei; Wang, Lu; Lu, Jianxi; Chen, Lei; Wang, Zhen; Chang, Jiang

    2011-11-01

    Implantation of synthetic materials into body elicits inflammatory host responses that limit medical device integration and biological performance. Since the effective use of biomaterials in vivo requires good biocompatibility and bio-functionality, it is vital that we assess the inflammatory reactions provoked by various implanted biomaterials. In chemical precipitation of β-tricalcium phosphate [β-Ca₃(PO₄)₂, β-TCP], the impurity of calcium pyrophosphate (Ca₂P₂O₇, CPP) will easily appear if the preparation conditions are not well controlled. To test the influences of CCP-impurity on the biocompatibility of the material, four groups of β-TCP ceramic samples doped with 0.5-10 wt % of CCP impurity, and pure β-TCP and CCP samples were fabricated and implanted in rat subcutaneous site for one, two, and four weeks. The host tissue responses to the ceramics were evaluated by histomorphometric analysis, and the results were compared with pure β-TCPbioceramics. The results show that the CPP impurity can elicit and stimulate the inflammatory responses at the tissue/implant interface. Moreover, with the increase of CPP doping amount, the inflammation increases apparently. However, the pure β-TCP bioceramics only present slight post-implantation inflammatory responses. The influence of the CPP doping on the inflammatory responses is mainly related to a microparticles release because of an insufficient sintering of β-TCP by CPP doping. The microparticle release could be at the origin of local inflammation and cell/tissue damages. Therefore, to obtain perfect biocompatibility and high quality β-TCP bioceramics, it is important to avoid and control the CPP impurity in the preparation of β-TCP powders and bioceramics.

  13. Investigation of zinc alkali pyrophosphate glasses. Part II: Local and medium range orders analysed by 1D/2D NMR

    Energy Technology Data Exchange (ETDEWEB)

    Rajbhandari, P. [UCCS UMR-CNRS 8181, Université de Lille1, Villeneuve d' Ascq (France); Chen, Y. [LASIR UMR-CNRS 8516, Université de Lille1, Villeneuve d' Ascq (France); Doumert, B. [IMMCL CNRS-FR2638, Université de Lille1, Villeneuve d' Ascq (France); Montagne, L. [UCCS UMR-CNRS 8181, Université de Lille1, Villeneuve d' Ascq (France); Tricot, G., E-mail: gregory.tricot@univ-lille1.fr [UCCS UMR-CNRS 8181, Université de Lille1, Villeneuve d' Ascq (France); LASIR UMR-CNRS 8516, Université de Lille1, Villeneuve d' Ascq (France)

    2015-04-01

    The structure of the (66-x)ZnO-xNa{sub 2}O-33.4P{sub 2}O{sub 5} composition line, selected for the development of low-Tg and stable glasses, has been investigated by 1D/2D NMR spectroscopy. If standard 1D {sup 31}P MAS-NMR experiments give access to the Q{sup n} speciation and show the presence of Q{sup 0}, Q{sup 1} and Q{sup 2} sites within the glass structure, application of the homonuclear through-space correlation technique ({sup 31}P DQ-SQ) allows for a more accurate description of the phosphate units. Clear distinction between the Q{sup 1} sites involved in dimmers or in longer chains has been derived from 2D NMR correlation maps and leads to the re-assignment of Q{sup 1} into Q{sup 1,1} and Q{sup 1,2} species. {sup 23}Na and {sup 23}Na({sup 31}P) REDOR MAS-NMR experiments have been used to analyse the Na{sup +} ions distribution and its interaction with the phosphate network. {sup 67}Zn static NMR experiments, performed at very high field, were carried out and suggest a constant Zn{sup 2+} coordination state all along the composition line. The results have been used to discuss the impact of the Zn{sup 2+}/Na{sup +} ratio on the extent of disorder within the glass network expressed in terms of Q{sup n} dismutation equilibrium constant and phosphate chain length distribution. - Highlights: • Structure of zinc alkali pyrophosphate glasses have been analysed by 1D/2D NMR. • 2D {sup 31}P experiments allow to separate Q{sup 1,1} and Q{sup 1,2} species. • {sup 67}Zn static NMR shows a constant signal all along the composition line.

  14. Sesquiterpene synthases Cop4 and Cop6 from Coprinus cinereus: Catalytic promiscuity and cyclization of farnesyl pyrophosphate geometrical isomers

    Science.gov (United States)

    Lopez-Gallego, Fernando; Agger, Sean A.; Pella, Daniel A.; Distefano, Mark D.; Schmidt-Dannert, Claudia

    2010-01-01

    Sesquiterpene synthases catalyze with different catalytic fidelity the cyclization of farnesyl pyrophosphate (FPP) into hundreds of known compounds with diverse structures and stereochemistries. Two sesquiterpene synthases, Cop4 and Cop6, were previously isolated from Coprinus cinereus as part of a fungal genome survey. This study investigates the reaction mechanism and catalytic fidelity of the two enzymes. Cyclization of all-trans-FPP ((E,E)-FPP) was compared to the cyclization of the cis-trans isomer of FPP ((Z,E)-FPP) as a surrogate for the secondary cisoid neryl cation intermediate generated by sesquiterpene synthases capable of isomerizing the C2-C3 π bond of all-trans-FPP. Cop6 is a “high-fidelity” α-cuprenene synthase that retains its fidelity under various conditions tested. Cop4 is a catalytically promiscuous enzyme that cyclizes (E,E)-FPP into multiple products, including (−)-germacrene D and cubebol. Changing the pH of the reaction drastically alters the fidelity of Cop4 and makes it a highly selective enzyme. Cyclization of (Z,E)-FPP by Cop4 and Cop6 yields products that are very different from those obtained with (E,E)-FPP. Conversion of (E,E)-FPP proceeds via a (6R)-β-bisabolyl carbocation in the case of Cop6 and an (E,E)-germacradienyl carbocation in the case of Cop4. However, (Z,E)-FPP is cyclized via a (6S)-β-bisabolene carbocation by both enzymes. Structural modeling suggests that differences in the active site and the loop that covers the active site of the two enzymes may explain their different catalytic fidelities. PMID:20419721

  15. The prevalence of chondrocalcinosis of the symphysis pubis on CT scan and correlation with calcium pyrophosphate dihydrate crystal deposition disease.

    Science.gov (United States)

    Patel, Trusha; Ryan, Lawrence; Dubois, Melissa; Carrera, Guillermo; Baynes, Keith; Mannem, Rajeev; Mulkerin, Jennifer; Visotcky, Alexis

    2016-03-01

    Calcium pyrophosphate dihydrate (CPP) crystal deposition in the articular cartilage can often be seen radiographically as chondrocalcinosis (CC). CPP crystals preferentially deposit in fibrocartilages such as the knee menisci and symphysis pubis (SP). We sought to determine the prevalence of CC in the SP on computed tomography (CT) of the abdomen and pelvis. This retrospective study involved readings on 1070 consecutive CTs of the abdomen and pelvis performed over 3 months in patients over 65 years of age. Medical records of 226 patients found to have CC were reviewed to determine age, gender, documentation of CPPD on problem lists or in medical histories, and whether radiology readings of the CTs mentioned CC. SP CC was identified in 21.1 % (226/1070) of consecutive CT scans with the mean age of CT+ patients being 78.6. Of the 226 patients with SP CC, the observation of CC was documented in only 5.3 % (12/226) of the radiology reports. Of the 12 instances in which the radiology reports mentioned CC, this observation was never (0/12) transmitted to the medical history or problem list. The prevalence of SP CC in patients older than 65 was 21.1 %. Since the majority of CTs of the abdomen and pelvis are not ordered for evaluation of musculoskeletal conditions, this is likely a true prevalence without selection bias. When CC of the SP was present on images, radiologists routinely overlooked or chose not to report CC. Even in the rare instances when it was reported, that information was not added to the medical history or problem list. There are several clinical situations (e.g., acute monoarthritis or atypical osteoarthritis) in which recognizing that a patient has CPP deposition would be useful. Taking the time to review images may yield clinically important findings that are not mentioned anywhere on the patient chart.

  16. Comparison of Activities and Properties of Pyrophosphate and Adenosine Triphosphate-Dependent Phosphofructokinases of Black Gram (Phaseolus mungo) Seeds.

    Science.gov (United States)

    Ashihara, H; Stupavska, S

    1984-09-01

    Both pyrophosphate-dependent phosphofructokinase (PPi-PFKase, EC 2.7.1.90) and ATPdependent phosphofructokinase (ATP-PFKase, EC 2.7. 1.11) were present in dry and germinated black gram seeds. In the absence of fructose-2,6-biphosphate (F2,6BP), the activity of PPi-PFKase expressed as nmol · min(-1) · (pair of cotyledons)(-1) was much lower than that of ATP-PFKase in both dry and germinated seeds. However, PPi-PFKase was activated by F2,6BP and its activity reached the same level as ATP-PFKase activity. ATP-PFKase showed sigmoidal kinetics respective to fructose-6-phosphate (F6P), while PPi-PFKase exhibited hyperbolic kinetics in the presence of F2,6BP. The F6P concentration for half maximal activity of ATP-PFKase (1.5 mM) was nearly 5 times lower than that of PPi-PFKase (7.1 mM). The apparent Km values of PPi-PFKase for PPi and that of ATP-PFKase for ATP were 0.29 mM and 0.23 mM, respectively. Phosphoenolpyruvate (PEP) and citrate inhibited ATP-PFKase activity, but they did not affect PPi-PFKase activity. The activity of PPi-PFKase was inhibited by Pi, while only a little Pi inhibition was observed in the case of ATP-PFKase. These results suggest that the control mechanism of PPi-PFKase and that of ATP-PFKase are quite different. In contrast to pineapple leaves (Carnal, N. W. and C. C. Black, Biochem. Biophys. Res. Commun. 86, 20-26, 1979) and caster bean seedlings (Krugar et al., FEBS Lett. 153, 409-412, 1983), PPi-PFKase is not the predominant PFKase activity in black gram seeds.

  17. Isopentenyl pyrophosphate-activated CD56+ {gamma}{delta} T lymphocytes display potent antitumor activity toward human squamous cell carcinoma.

    Science.gov (United States)

    Alexander, Alan A Z; Maniar, Amudhan; Cummings, Jean-Saville; Hebbeler, Andrew M; Schulze, Dan H; Gastman, Brian R; Pauza, C David; Strome, Scott E; Chapoval, Andrei I

    2008-07-01

    The expression of CD56, a natural killer cell-associated molecule, on alphabeta T lymphocytes correlates with their increased antitumor effector function. CD56 is also expressed on a subset of gammadelta T cells. However, antitumor effector functions of CD56(+) gammadelta T cells are poorly characterized. To investigate the potential effector role of CD56(+) gammadelta T cells in tumor killing, we used isopentenyl pyrophosphate and interleukin-2-expanded gammadelta T cells from peripheral blood mononuclear cells of healthy donors. Thirty to 70% of expanded gammadelta T cells express CD56 on their surface. Interestingly, although both CD56(+) and CD56(-) gammadelta T cells express comparable levels of receptors involved in the regulation of gammadelta T-cell cytotoxicity (e.g., NKG2D and CD94), only CD56(+) gammadelta T lymphocytes are capable of killing squamous cell carcinoma and other solid tumor cell lines. This effect is likely mediated by the enhanced release of cytolytic granules because CD56(+) gammadelta T lymphocytes expressed higher levels of CD107a compared with CD56(-) controls following exposure to tumor cell lines. Lysis of tumor cell lines is blocked by concanamycin A and a combination of anti-gammadelta T-cell receptor + anti-NKG2D monoclonal antibody, suggesting that the lytic activity of CD56(+) gammadelta T cells involves the perforin-granzyme pathway and is mainly gammadelta T-cell receptor/NKG2D dependent. Importantly, CD56-expressing gammadelta T lymphocytes are resistant to Fas ligand and chemically induced apoptosis. Our data indicate that CD56(+) gammadelta T cells are potent antitumor effectors capable of killing squamous cell carcinoma and may play an important therapeutic role in patients with head and neck cancer and other malignancies.

  18. Growth inhibitory effect of paratocarpin E, a prenylated chalcone isolated from Euphorbia humifusa Wild., by induction of autophagy and apoptosis in human breast cancer cells.

    Science.gov (United States)

    Gao, Suyu; Sun, Dejuan; Wang, Guan; Zhang, Jin; Jiang, Yingnan; Li, Guoyu; Zhang, Ke; Wang, Lei; Huang, Jian; Chen, Lixia

    2016-12-01

    Five flavones, including four flavonoids and one prenylated chalcone (paratocarpin E), were isolated from E. humifusa. and their chemical structures were established by spectroscopic analyses. We assessed the efficacy of these compounds against the growth of human breast cancer, leukemic, kidney cancer cell lines. Among them, paratocarpin E showed significant cytotoxicity against these cancer cell lines with an IC50 of 19.6μM on the growth of MCF-7 cells. Paratocarpin E treatment of MCF-7 cells resulted in typical apoptotic features via increasing expression of activated caspase-8 and -9 and PARP cleavage. Moreover, paratocarpin E altered the expression of Bax and Bcl-2, leading to the release of cytochrome c from the mitochondria into the cytosol, suggesting that the mitochondria-mediated apoptosis was initiated. In addition, paratocarpin E increased the MDC-positive autophagic vacuoles, the ratio of LC3-II/LC3-I protein levels of Beclin-1, but decreased p62 expression, indicating the potent pro-autophagic effects of paratocarpin E in MCF-7 cells. Mechanistically, cell death induced by paratocarpin E is able to induce apoptosis of MCF-7 cells by activating p38 and JNK signaling pathway while inhibiting Erk pathway. Furthermore, paratocarpin E promotes the activation and nuclear translocation of NF-κB, which plays an important role in balancing paratocarpin E-mediated apoptosis and autophagy. The molecular docking study also revealed that paratocarpin E bound to Fas and NF-κB complex. These findings provide initial evidences that paratocarpin E can be used as a potential anti-cancer drug in future for breast cancer therapy.

  19. Modelling the effect of pH, sodium chloride and sodium pyrophosphate on the thermal resistance of Escherichia coli O157:H7 in ground beef

    Science.gov (United States)

    A fractional factorial design was used to assess the combined effects of four internal temperatures (55.0, 57.5, 60.0 and 62.5C) and five concentrations of sodium chloride (NaCl) (0.0, 1.5, 3.0, 4.5 and 6.0 wt/wt%) and sodium pyrophosphate (SPP) (0.0, 0.1, 0.15, 0.2 and 0.3 wt/wt%) on the heat resis...

  20. [Diagnostic possibilities of static gamma-scintigraphy using 99mTc pyrophosphate and Tc 99m phosphate in children with glomerulo nephritis].

    Science.gov (United States)

    Mil'ko, V I; Bagdasarova, I V; Moskalenko, N I; Ivanov, D D

    1989-01-01

    Children with nephrotic glomerulonephritis were examined for incorporation of 99mTc-pyrophosphate and 99mTc-phosphone. The relationship was discovered between the accumulation of the radiopharmaceutical drug and the sensitivity to glucocorticoids used in the pathogenetic treatment. Accumulation of the drug in the course of the treatment documents the presence of complete, partial remission or the disease activity. It is recommended that static gammascintigraphy should be carried out for early assessment of the efficacy of the treatment and its correction.

  1. Change perspective to increase diagnostic accuracy of ultrasonography in calcium pyrophosphate dihydrate deposition disease! A new approach: the axial scan of the meniscus

    Directory of Open Access Journals (Sweden)

    G. Filippou

    2015-03-01

    Full Text Available Ultrasonography (US is a relevant tool in the study of calcium pyrophosphate dihydrate (CPP deposition disease. However, differential diagnosis of hyperechoic deposits within the fibrocartilage can be difficult; moreover, US study is limited by the need of an adequate acoustic window. We describe a US scanning technique that offers a new viewpoint in the study of knee meniscal structure: a longitudinal scan performed according to the long axis of meniscus. This technique proves to be particularly useful for the identification of CPP deposition, but could also improve the US diagnostic utility and accuracy in other meniscal pathologies.

  2. /sup 99m/Tc-aminohexylidendiphosphonate and /sup 99m/Tc-pyrophosphate in the scintigraphic diagnosis of experimental myocardial infarction in dogs

    Energy Technology Data Exchange (ETDEWEB)

    Duska, F.; Hadas, L.; Vizda, J.; Kafka, P.; Urbanova, E.; Palicka, V.; Mazurova, Y.; Kuba, M.; Grossman, V.

    1988-10-01

    /sup 99m/Tc-aminohexylidendiphosphonate (/sup 99m/Tc-AHDP) is a new Czechoslovak pharmaceutical of the phosphonate line which contains the amino group NH/sub 2/ in its molecule. This substance was tested in 5 dogs with experimentally provoked 48-h old myocardial infarction. The in-vivo scan and the radioactivity of tissue samples demonstrated that /sup 99m/Tc-AHDP is as suitable for imaging acute myocardial infarction as is the commonly used /sup 99m/Tc-pyrophosphate.

  3. Synergistic effects of ethanol and isopentenyl pyrophosphate on expansion of γδ T cells in synovial fluid from patients with arthritis

    DEFF Research Database (Denmark)

    Laurent, Agneta J; Bindslev, Niels; Johansson, Björn;

    2014-01-01

    Low to moderate ethanol consumption has been associated with protective effects in autoimmune diseases such as rheumatoid arthritis, RA. An expansion of γδ T cells induced by isopentenyl pyrophosphate, IPP, likewise seems to have a protective role in arthritis. The aim of this project was to test...... with ethanol in presence of risedronate, which has the ability to increase endogenous levels of IPP. We conclude that expansion of γδ T cells by combinatorial drug effects, possibly in fixed-dose combination, FDC, of ethanol in the presence of IPP might give a protective role in diseases such as arthritis....

  4. Antimony doped tin oxides and their composites with tin pyrophosphates as catalyst supports for oxygen evolution reaction in proton exchange membrane water electrolysis

    DEFF Research Database (Denmark)

    Xu, Junyuan; Li, Qingfeng; Hansen, Martin Kalmar

    2012-01-01

    Proton exchange membrane water electrolysers operating at typically 80 °C or at further elevated temperatures suffer from insufficient catalyst activity and durability. In this work, antimony doped tin oxide nanoparticles were synthesized and further doped with an inorganic proton conducting phase...... based on tin pyrophosphates as the catalyst support. The materials showed an overall conductivity of 0.57 S cm−1 at 130 °C under the water vapor atmosphere with a contribution of the proton conduction. Using this composite support, iridium oxide nanoparticle catalysts were prepared and characterized...

  5. Engineering, conjugation, and immunogenicity assessment of Escherichia coli O121 O antigen for its potential use as a typhoid vaccine component.

    Science.gov (United States)

    Wetter, Michael; Kowarik, Michael; Steffen, Michael; Carranza, Paula; Corradin, Giampietro; Wacker, Michael

    2013-07-01

    State-of-the-art production technologies for conjugate vaccines are complex, multi-step processes. An alternative approach to produce glycoconjugates is based on the bacterial N-linked protein glycosylation system first described in Campylobacter jejuni. The C. jejuni N-glycosylation system has been successfully transferred into Escherichia coli, enabling in vivo production of customized recombinant glycoproteins. However, some antigenic bacterial cell surface polysaccharides, like the Vi antigen of Salmonella enterica serovar Typhi, have not been reported to be accessible to the bacterial oligosaccharyltransferase PglB, hence hamper development of novel conjugate vaccines against typhoid fever. In this report, Vi-like polysaccharide structures that can be transferred by PglB were evaluated as typhoid vaccine components. A polysaccharide fulfilling these requirements was found in Escherichia coli serovar O121. Inactivation of the E. coli O121 O antigen cluster encoded gene wbqG resulted in expression of O polysaccharides reactive with antibodies raised against the Vi antigen. The structure of the recombinantly expressed mutant O polysaccharide was elucidated using a novel HPLC and mass spectrometry based method for purified undecaprenyl pyrophosphate (Und-PP) linked glycans, and the presence of epitopes also found in the Vi antigen was confirmed. The mutant O antigen structure was transferred to acceptor proteins using the bacterial N-glycosylation system, and immunogenicity of the resulting conjugates was evaluated in mice. The conjugate-induced antibodies reacted in an enzyme-linked immunosorbent assay with E. coli O121 LPS. One animal developed a significant rise in serum immunoglobulin anti-Vi titer upon immunization.

  6. PRS5, the Fifth Member of the Phosphoribosyl Pyrophosphate Synthetase Gene Family in Saccharomyces cerevisiae, Is Essential for Cell Viability in the Absence of either PRS1 or PRS3

    OpenAIRE

    Hernando, Yolanda; Parr, Adrian; Schweizer, Michael

    1998-01-01

    In Saccharomyces cerevisiae, an open reading frame, YOL061w, encodes a polypeptide with sequence similarity to the four known 5-phosphoribosyl-1(α)-pyrophosphate synthetase (PRS) genes since it contains a divalent cation binding site and a phosphoribosyl pyrophosphate binding site. We regard YOL061w as the fifth member of the PRS gene family, PRS5. Loss of Prs5p has a significant impact on PRS enzyme activity, causing it to be reduced by 84%. On the other hand, Δprs5 strains are not affected ...

  7. Crystal arthritides - gout and calcium pyrophosphate arthritis : Part 2: clinical features, diagnosis and differential diagnostics.

    Science.gov (United States)

    Schlee, S; Bollheimer, L C; Bertsch, T; Sieber, C C; Härle, P

    2017-02-23

    Gout develops in four stages beginning with an asymptomatic increase in blood levels of uric acid. An acute gout attack is an expression of an underlying inflammatory process, which in the course of time is self-limiting. Without therapy monosodium urate crystals remain in the synovial fluid and synovial membrane and trigger more acute attacks. In the course of the disease monosodium urate crystals form deposits (tophi) leading in severe forms to irreversible joint deformities with loss of functionality. In 20% of cases gout leads to involvement of the kidneys. Overproduction of uric acid can cause nephrolithiasis. These stones can be composed of uric acid or calcium phosphate. Another form of kidney disease caused by gout is uric acid nephropathy. This is a form of abacterial chronic inflammatory response with deposition of sodium urate crystals in the medullary interstitium. Acute obstructive nephropathy is relatively rare and characterized by renal failure due to uric acid precipitation in the tubules because of rapid cell lysis that occurs, for example, with chemotherapy. There is a causal interdependence between the occurrence of hyperuricemia and hypertension. Uric acid activates the renin-angiotensin-aldosterone (RAA) system and inhibits nitric oxide (NO) with the possible consequence of a rise in systemic vascular resistance or arteriolar vasculopathy; however, uric acid is also an apparently independent risk factor for atherosclerosis. In contrast to young patients, the diagnosis of an acute gout attack in the elderly can be a challenge for the physician. Polyarticular manifestations and obscure symptoms can make it difficult to differentiate it from rheumatoid arthritis and calcium pyrophosphate deposition disease (CPPD). Aspiration of synovial fluid with visualization of urate crystals using compensated polarized light microscopy is the gold standard for diagnosis of acute gout. Moreover, analysis of synovial fluid enables a distinction from septic

  8. The influence of atmosphere conditions on Escherichia coli and Salmonella typhi radiosensitization in irradiated ground beef containing carvacrol and tetrasodium pyrophosphate

    Science.gov (United States)

    Lacroix, M.; Borsa, J.; Chiasson, F.; Ouattara, B.

    2004-09-01

    The radiosensitization of Escherichia coli and Salmonella typhi in presence of carvacrol (1.0%) and tetrasodium pyrophosphate (0.1%) in ground beef packed under four different atmospheres (air; 100% CO 2; MAP : 60% O 2-30% CO 2-10% N 2 and vacuum) was determined. Medium fat ground beef containing carvacrol and tetrasodium pyrophosphate was inoculated with E. coli or S. typhi. Samples were packed under different atmospheres as described before and irradiated at doses from 0.1 to 0.6 kGy in presence of E. coli and from 0.50 to 2.0 kGy for S. typhi. Results indicated that the best increase in radiosensitization was observed in samples packed under MAP. The D10 values were 0.046 kGy for E. coli and 0.053 kGy for S. typhi. Both bacteria were more resistant to irradiation under air, in the absence of active compound. A D10 values of 0.126 kGy for E. coli and 0.526 kGy for S. typhi was observed.

  9. The influence of atmosphere conditions on Escherichia coli and Salmonella typhi radiosensitization in irradiated ground beef containing carvacrol and tetrasodium pyrophosphate

    Energy Technology Data Exchange (ETDEWEB)

    Lacroix, M. E-mail: monique.lacroix@inrs-iaf.uquebec.ca; Borsa, J.; Chiasson, F.; Ouattara, B

    2004-10-01

    The radiosensitization of Escherichia coli and Salmonella typhi in presence of carvacrol (1.0%) and tetrasodium pyrophosphate (0.1%) in ground beef packed under four different atmospheres (air; 100% CO{sub 2}; MAP : 60% O{sub 2}-30% CO{sub 2}-10% N{sub 2} and vacuum) was determined. Medium fat ground beef containing carvacrol and tetrasodium pyrophosphate was inoculated with E. coli or S. typhi. Samples were packed under different atmospheres as described before and irradiated at doses from 0.1 to 0.6 kGy in presence of E. coli and from 0.50 to 2.0 kGy for S. typhi. Results indicated that the best increase in radiosensitization was observed in samples packed under MAP. The D{sub 10} values were 0.046 kGy for E. coli and 0.053 kGy for S. typhi. Both bacteria were more resistant to irradiation under air, in the absence of active compound. A D{sub 10} values of 0.126 kGy for E. coli and 0.526 kGy for S. typhi was observed.

  10. Safety and efficacy of a novel tartar control dentifrice containing 3.3% pyrophosphate: a controlled six-month clinical trial.

    Science.gov (United States)

    Segreto, V A; Stevens, D P; Schulte, M C; Fortna, R H; Gerlach, R W

    1998-01-01

    This study was undertaken to establish the tartar control efficacy and long-term safety of a new tartar control dentifrice that was formulated to enhance aesthetics and consumer acceptability. In a partially randomized, examiner-blind clinical trial, the experimental dentifrice, Crest MultiCare with 3.3% pyrophosphate, was compared to two currently marketed control dentifrices, Crest Regular Paste or Crest Tartar Protection Paste with 5.0% pyrophosphate. The eight-month trial model included a two-month pretest period to establish calculus formation after prophylaxis, followed by a six-month test period to evaluate efficacy and safety. Following the pretest period, 456 subjects were allocated to one of the three treatment groups and then monitored for calculus accumulation. After three and six months' test product use, the Crest MultiCare group experienced reductions in calculus accumulation of 28.9% and 32.3%, respectively compared to the regular control dentifrice. Over the six-month observation period, the experimental tartar control and the marketed tartar control dentifrices were comparable on adverse event frequency, type or severity, and no subject discontinued treatment due to an oral soft tissue adverse event. In this partially randomized and controlled six-month clinical trial, this new dentifrice exhibited tartar control efficacy, with a comparable overall safety profile to a marketed tartar control dentifrice.

  11. Orchestration of thiamin biosynthesis and central metabolism by combined action of the thiamin pyrophosphate riboswitch and the circadian clock in Arabidopsis.

    Science.gov (United States)

    Bocobza, Samuel E; Malitsky, Sergey; Araújo, Wagner L; Nunes-Nesi, Adriano; Meir, Sagit; Shapira, Michal; Fernie, Alisdair R; Aharoni, Asaph

    2013-01-01

    Riboswitches are natural RNA elements that posttranscriptionally regulate gene expression by binding small molecules and thereby autonomously control intracellular levels of these metabolites. Although riboswitch-based mechanisms have been examined extensively, the integration of their activity with global physiology and metabolism has been largely overlooked. Here, we explored the regulation of thiamin biosynthesis and the consequences of thiamin pyrophosphate riboswitch deficiency on metabolism in Arabidopsis thaliana. Our results show that thiamin biosynthesis is largely regulated by the circadian clock via the activity of the THIAMIN C SYNTHASE (THIC) promoter, while the riboswitch located at the 3' untranslated region of this gene controls overall thiamin biosynthesis. Surprisingly, the results also indicate that the rate of thiamin biosynthesis directs the activity of thiamin-requiring enzymes and consecutively determines the rate of carbohydrate oxidation via the tricarboxylic acid cycle and pentose-phosphate pathway. Our model suggests that in Arabidopsis, the THIC promoter and the thiamin-pyrophosphate riboswitch act simultaneously to tightly regulate thiamin biosynthesis in a circadian manner and consequently sense and control vital points of core cellular metabolism.

  12. Concepts and applications for influenza antigenic cartography

    Science.gov (United States)

    Cai, Zhipeng; Zhang, Tong; Wan, Xiu-Feng

    2011-01-01

    Influenza antigenic cartography projects influenza antigens into a two or three dimensional map based on immunological datasets, such as hemagglutination inhibition and microneutralization assays. A robust antigenic cartography can facilitate influenza vaccine strain selection since the antigenic map can simplify data interpretation through intuitive antigenic map. However, antigenic cartography construction is not trivial due to the challenging features embedded in the immunological data, such as data incompleteness, high noises, and low reactors. To overcome these challenges, we developed a computational method, temporal Matrix Completion-Multidimensional Scaling (MC-MDS), by adapting the low rank MC concept from the movie recommendation system in Netflix and the MDS method from geographic cartography construction. The application on H3N2 and 2009 pandemic H1N1 influenza A viruses demonstrates that temporal MC-MDS is effective and efficient in constructing influenza antigenic cartography. The web sever is available at http://sysbio.cvm.msstate.edu/AntigenMap. PMID:21761589

  13. The T cell antigen receptor: the Swiss army knife of the immune system.

    Science.gov (United States)

    Attaf, M; Legut, M; Cole, D K; Sewell, A K

    2015-07-01

    The mammalian T cell receptor (TCR) orchestrates immunity by responding to many billions of different ligands that it has never encountered before and cannot adapt to at the protein sequence level. This remarkable receptor exists in two main heterodimeric isoforms: αβ TCR and γδ TCR. The αβ TCR is expressed on the majority of peripheral T cells. Most αβ T cells recognize peptides, derived from degraded proteins, presented at the cell surface in molecular cradles called major histocompatibility complex (MHC) molecules. Recent reports have described other αβ T cell subsets. These 'unconventional' T cells bear TCRs that are capable of recognizing lipid ligands presented in the context of the MHC-like CD1 protein family or bacterial metabolites bound to the MHC-related protein 1 (MR1). γδ T cells constitute a minority of the T cell pool in human blood, but can represent up to half of total T cells in tissues such as the gut and skin. The identity of the preferred ligands for γδ T cells remains obscure, but it is now known that this receptor can also functionally engage CD1-lipid, or immunoglobulin (Ig) superfamily proteins called butyrophilins in the presence of pyrophosphate intermediates of bacterial lipid biosynthesis. Interactions between TCRs and these ligands allow the host to discriminate between self and non-self and co-ordinate an attack on the latter. Here, we describe how cells of the T lymphocyte lineage and their antigen receptors are generated and discuss the various modes of antigen recognition by these extraordinarily versatile receptors.

  14. Antigen Export Reduces Antigen Presentation and Limits T Cell Control of M. tuberculosis.

    Science.gov (United States)

    Srivastava, Smita; Grace, Patricia S; Ernst, Joel D

    2016-01-13

    Persistence of Mycobacterium tuberculosis results from bacterial strategies that manipulate host adaptive immune responses. Infected dendritic cells (DCs) transport M. tuberculosis to local lymph nodes but activate CD4 T cells poorly, suggesting bacterial manipulation of antigen presentation. However, M. tuberculosis antigens are also exported from infected DCs and taken up and presented by uninfected DCs, possibly overcoming this blockade of antigen presentation by infected cells. Here we show that the first stage of this antigen transfer, antigen export, benefits M. tuberculosis by diverting bacterial proteins from the antigen presentation pathway. Kinesin-2 is required for antigen export and depletion of this microtubule-based motor increases activation of antigen-specific CD4 T cells by infected cells and improves control of intracellular infection. Thus, although antigen transfer enables presentation by bystander cells, it does not compensate for reduced antigen presentation by infected cells and represents a bacterial strategy for CD4 T cell evasion.

  15. THE LYMPH SELF ANTIGEN REPERTOIRE

    Directory of Open Access Journals (Sweden)

    Laura eSantambrogio

    2013-12-01

    Full Text Available The lymphatic fluid originates from the interstitial fluid which bathes every parenchymal organ and reflects the omic composition of the tissue from which it originates in its physiological or pathological signature. Several recent proteomic analyses have mapped the proteome-degradome and peptidome of this immunologically relevant fluid pointing to the lymph as an important source of tissue-derived self-antigens. A vast array of lymph-circulating peptides have been mapped deriving from a variety of processing pathways including caspases, cathepsins, MMPs, ADAMs, kallikreins, calpains and granzymes, among others. These self peptides can be directly loaded on circulatory dendritic cells and expand the self-antigenic repertoire available for central and peripheral tolerance.

  16. Towards in vivo regulon kinetics: PurR activation by 5-phosphoribosyl-a-1-pyrophosphate during purine depletion in Lactococcus lactis

    DEFF Research Database (Denmark)

    Jendresen, Christian Bille; Dimitrov, Peter; Gautier, Laurent;

    2014-01-01

    5-phosphoribosyl-a-1-pyrophosphate (PRPP) and individual mRNA levels, whereby unambiguous and homogeneous relations could be obtained for PurR regulated genes, thus linking a specific regulon to a specific metabolite. As PurR activates gene expression upon binding of PRPP, the pur mRNA curves......, for elucidating regulatory networks in vivo....

  17. Bacterial phospholipide antigens and their taxonomic significance.

    Science.gov (United States)

    Karalnik, B V; Razbash, M P; Akhmetova, E A

    1981-01-01

    The investigation of interrelationships between the phospholipides of various microorganisms (33 strains of corynebacteria, mycobacteria and staphylococci) using crossed antibody neutralization reactions with phospholipide antigenic erythrocyte diagnostic was used for the assessment of the degree of antigenic propinquity and antigenic differences between the phospholipides of bacteria of the same species, genus, and of different genera. The role of the determinants of the corresponding (their own) and "foreign" genera in the antigenic differences between the phospholipides of the microorganisms investigated was established. On the basis of the results obtained the conclusion has been drawn that the method of assessment of antigenic interrelationships between phospholipides can be used for the study of some taxonomic problems.

  18. [HLA antigens in juvenile rheumatoid arthritis].

    Science.gov (United States)

    Rumba, I V; Sochnev, A M; Kukaĭne, E M; Burshteĭn, A M; Benevolenskaia, L I

    1990-01-01

    Antigens of I class HLA system (locus A and B) were investigated in 67 patients of Latvian nationality suffering from juvenile rheumatoid arthritis (JRA). Associations of HLA antigens with juvenile rheumatoid arthritis partially coincided with the ones revealed earlier. Typing established an increased incidence of antigen B27 (p less than 0.01) and gaplotype A2, B40 (p less than 0.01). Antigen B15 possessed a protective action with respect to JRA. Interlocus combinations demonstrated a closer association with the disease than a single antigen. The authors also revealed markers of various clinico-anatomical variants of JRA.

  19. Calcium pyrophosphate arthritis

    Science.gov (United States)

    ... are similar, CPPD arthritis can be confused with: Gouty arthritis (gout) Osteoarthritis Rheumatoid arthritis Exams and Tests Most arthritic ... A.M. Editorial team. Related MedlinePlus Health Topics Gout Browse the Encyclopedia A.D.A.M., Inc. ...

  20. Calcium Pyrophosphate Deposition (CPPD)

    Science.gov (United States)

    ... Cryopyrin-Associated Autoinflammatory Syndrome (CAPS) (Juvenile) Dermatomyositis (Juvenile) Familial Mediterranean Fever (Juvenile) Fibromyalgia Giant Cell Arteritis Glucocorticoid-induced Osteoperosis ...

  1. Calcium Pyrophosphate Deposition (CPPD)

    Science.gov (United States)

    ... can cause inflammation that leads to joint pain, warmth and swelling. In most cases, it is not ... support from other health care providers. These include physical and occupational therapists and nurses. Updated March 2017 ...

  2. Common antigens between hydatid cyst and cancers

    Directory of Open Access Journals (Sweden)

    Shima Daneshpour

    2016-01-01

    Full Text Available Background: Different research groups reported a negative correlation between cancers and parasitical infections. As an example, the prevalence of a hydatid cyst among patients with cancer was significantly lower than its prevalence among normal population. Tn antigens exist both in cancer and hydatid cyst. This common antigen may be involved in the effect of parasite on cancer growth. So in this work, common antigens between hydatid cyst and cancers have been investigated. Materials and Methods: Different hydatid cyst antigens including hydatid fluid, laminated and germinal layer antigens, and excretory secretory antigens of protoscolices were run in SDS PAGE and transferred to NCP paper. In western immunoblotting, those antigens were probed with sera of patients with different cancer and also sera of non-cancer patients. Also, cross reaction among excretory secretory products of cancer cells and antisera raised against different hydatid cyst antigen was investigated. Results: In western immunoblotting, antisera raised against laminated and germinal layers of hydatid cyst reacted with excretory secretory products of cancer cells. Also, a reaction was detected between hydatid cyst antigens and sera of patients with some cancers. Conclusion: Results of this work emphasize existence of common antigens between hydatid cyst and cancers. More investigation about these common antigens is recommended.

  3. Stable solid-phase Rh antigen.

    Science.gov (United States)

    Yared, M A; Moise, K J; Rodkey, L S

    1997-12-01

    Numerous investigators have attempted to isolate the Rh antigens in a stable, immunologically reactive form since the discovery of the Rh system over 56 years ago. We report here a successful and reproducible approach to solubilizing and adsorbing the human Rh antigen(s) to a solid-phase matrix in an antigenically active form. Similar results were obtained with rabbit A/D/F red blood cell antigens. The antigen preparation was made by dissolution of the red blood cell membrane lipid followed by fragmentation of the residual cytoskeleton in an EDTA solution at low ionic strength. The antigenic activity of the soluble preparations was labile in standard buffers but was stable in zwitterionic buffers for extended periods of time. Further studies showed that the antigenic activity of these preparations was enhanced, as was their affinity for plastic surfaces, in the presence of acidic zwitterionic buffers. Adherence to plastic surfaces at low pH maintained antigenic reactivity and specificity for antibody was retained. The data show that this approach yields a stable form of antigenically active human Rh D antigen that could be used in a red blood cell-free assay for quantitative analysis of Rh D antibody and for Rh D antibody immunoadsorption and purification.

  4. Common antigens between hydatid cyst and cancers

    Science.gov (United States)

    Daneshpour, Shima; Bahadoran, Mehran; Hejazi, Seyed Hossein; Eskandarian, Abas Ali; Mahmoudzadeh, Mehdi; Darani, Hossein Yousofi

    2016-01-01

    Background: Different research groups reported a negative correlation between cancers and parasitical infections. As an example, the prevalence of a hydatid cyst among patients with cancer was significantly lower than its prevalence among normal population. Tn antigens exist both in cancer and hydatid cyst. This common antigen may be involved in the effect of parasite on cancer growth. So in this work, common antigens between hydatid cyst and cancers have been investigated. Materials and Methods: Different hydatid cyst antigens including hydatid fluid, laminated and germinal layer antigens, and excretory secretory antigens of protoscolices were run in SDS PAGE and transferred to NCP paper. In western immunoblotting, those antigens were probed with sera of patients with different cancer and also sera of non-cancer patients. Also, cross reaction among excretory secretory products of cancer cells and antisera raised against different hydatid cyst antigen was investigated. Results: In western immunoblotting, antisera raised against laminated and germinal layers of hydatid cyst reacted with excretory secretory products of cancer cells. Also, a reaction was detected between hydatid cyst antigens and sera of patients with some cancers. Conclusion: Results of this work emphasize existence of common antigens between hydatid cyst and cancers. More investigation about these common antigens is recommended. PMID:26962511

  5. THE PREVALENCE AND CLINICAL FEATURES OF GOUT AND CALCIUM PYROPHOSPHATE DEPOSITION DISEASE IN PATIENTS WITH ACUTE ARTHRITIS

    Directory of Open Access Journals (Sweden)

    M. S. Eliseev

    2015-01-01

    Full Text Available Objective: to study the rate of gout and calcium pyrophosphate deposition disease (CPDD and to provide their clinical characteristics in patients with acute arthritis.Subjects and methods. The investigation enrolled 150 patients (97 men and 53 women with acute mono- or oligoarthritis of no more than 2 weeks’ duration who had visited the Outpatient Department of V.A. Nasonova Research Institute of Rheumatology. Their mean age was 60.2±12.0 years (range, 28–76 years. All the patients underwent inflamed joint puncture and synovial fluid (SF crystal identification by polarized microscopy using an Olympus CX31-P compensator.The diagnosis of CPDD was established in compliance with the criteria elaborated by D. McCarty. Gout was diagnosed only when sodium monourate (SMU crystals were found in SF.Results and discussion. The investigation revealed gout in 51 (34% patients, CPDD in 45 (30%, coincidence of gout and CPDD in 15 (14%, and 39 (26% patients had other diseases: 15 (10% – osteoarthritis, 6 (4% – rheumatoid arthritis, 5 (3% – septic arthritis, 5 (3% – psoriatic arthritis, 2 (1% – ankylosing spondyloarthritis, 4 (3% – injury, and 5 (3% – undifferentiated spondyloarthritis. There were 40 men and 11 women among the patients with gout and 13 men and 32 women among those with CPDD. The patients with gout were younger than those with CPDD (35.5±8.9 and 58.4±12.8 years, respectively; p < 0.05. In the patients with CPDD, knee, ankle, and first metatarsophalangeal joint arthritis was present in 34 (76.3%, 17 (30.3%, and 4 (9% cases, respectively. Arthritis developed within a few hours in 90% of the patients with gout and in 33.3% of those with CPDD (p < 0.001. Monoarthritis was significantly more common in gout whereas oligoarthritis – in CPDD (p < 0.05. Visual analog scale pain intensity averaged 78.4±12.5 mm and 54.32±22.02 mm (p < 0.05, duration of arthritis – 10.3±3.8 days and 3.4±2.1 days (p < 0.05 in gout

  6. One-pot synthesis of highly greenish-yellow fluorescent nitrogen-doped graphene quantum dots for pyrophosphate sensing via competitive coordination with Eu(3+) ions.

    Science.gov (United States)

    Lin, Liping; Song, Xinhong; Chen, Yiying; Rong, Mingcong; Zhao, Tingting; Jiang, Yaqi; Wang, Yiru; Chen, Xi

    2015-10-01

    Highly fluorescent nitrogen-doped graphene quantum dots (N-GQDs) with greenish-yellow emission and quantum yield of 13.2% have been synthesized via a one-pot hydrothermal method. The obtained N-GQDs displayed excellent optical properties, high photostability and resistance to strong ion strength. Based on the higher affinity of pyrophosphate (PPi) than carboxyl and amido groups on the surface of the N-GQDs to Eu(3+), a Eu(3+)-modulated N-GQD off-on fluorescent probe for PPi detection was constructed with a detection limit of 0.074 μM. The detection process was simple in design, easy to operate, and showed a highly selective response to PPi in the presence of co-existing anions. This work widens the applications of N-GQDs with versatile functionality and reactivity in clinical diagnostics and as biosensors.

  7. Experimental Design-Based Response Surface Methodology Optimization for Synthesis of β-Mercapto Carbonyl Derivatives as Antimycobacterial Drugs Catalyzed by Calcium Pyrophosphate

    Directory of Open Access Journals (Sweden)

    Younes Abrouki

    2014-01-01

    Full Text Available A simple protocol for the efficient preparation of β-mercapto carbonyl derivatives as antimycobacterial drugs has been achieved via Thia-Michael reaction between chalcones derivatives and thiols in the presence of calcium pyrophosphate as a heterogeneous catalyst under mild reaction conditions. The central composite design was used to design an experimental program to provide data to model the effects of various factors on reaction yield (Y. The variables chosen were catalyst weight X1, reaction time X2, and solvent volume X3. The mathematical relationship of reaction yield on the three significant independent variables can be approximated by a nonlinear polynomial model. Predicted values were found to be in good agreement with experimental values. The optimum reaction conditions for reaction model (chalcone and thiophenol obtained by response surface were applied to other substrates. This procedure provides several advantages such as high yield, clean product formation, and short reaction time.

  8. Aggregation-Induced Emission Active Metal-Free Chemosensing Platform for Highly Selective Turn-On Sensing and Bioimaging of Pyrophosphate Anion.

    Science.gov (United States)

    Gogoi, Abhijit; Mukherjee, Sandipan; Ramesh, Aiyagari; Das, Gopal

    2015-07-07

    We report the synthesis of a metal-free chemosensor for highly selective sensing of pyrophosphate (PPi) anion in physiological medium. The novel phenylbenzimidazole functionalized imine containing chemosensor (L; [2,6-bis(((4-(1H-benzo[d]imidazol-2-yl)phenyl)imino) methyl)-4 methyl phenol]) could sense PPi anion through "turn-on" colorimetric and fluorimetric responses in a very competitive environment. The overall sensing mechanism is based on the aggregation-induced emission (AIE) phenomenon. Moreover, a real time in-field device application was demonstrated by sensing PPi in paper strips coated with L. Interestingly, detection of intracellular PPi ions in model human cells could also be possible by fluorescence microscopic studies without any toxicity to these cells.

  9. Myocardial infarction determined by technetium-99m pyrophosphate single-photon tomography complicating elective coronary artery bypass grafting for angina pectoris

    Energy Technology Data Exchange (ETDEWEB)

    Burns, R.J.; Gladstone, P.J.; Tremblay, P.C.; Feindel, C.M.; Salter, D.R.; Lipton, I.H.; Ogilvie, R.R.; David, T.E.

    1989-06-15

    The incidence of acute myocardial infarction (AMI) complicating coronary artery bypass grafting (CABG) has previously been based on concordance of electrocardiographic, enzymatic and scintigraphic criteria. Technetium-99m pyrophosphate (Tc-PPi) single-photon emission computed tomography now enables detection of AMI with high sensitivity and specificity. Using this technique, perioperative AMI was detected in 12 of 58 patients (21%) undergoing successful elective CABG for stable angina pectoris. Stepwise multivariate logistic regression analysis was performed to compare the predictive value of preoperative (New York Heart Association class, left ventricular ejection fraction and use of beta blockers) and intraoperative (number of grafts constructed, use of internal mammary anastomoses, use of sequential saphenous vein grafts, smallest grafted distal vessel lumen caliber and aortic cross-clamp time) variables. Preoperative New York Association class (p = 0.04) and smallest grafted distal vessel lumen caliber (p = 0.03) were significant multivariate predictors of perioperative AMI. Only 1 perioperative patient with AMI (and 1 pyrophosphate-negative patient) developed new Q waves. Serum creatine kinase-MB was higher in patients with AMI by repeated measures analysis of variance (p = 0.0003). Five AMIs occurred in myocardial segments revascularized using sequential saphenous vein grafts, and 7 in segments perfused by significantly stenosed epicardial vessels with distal lumen diameter and perfusion territory considered too small to warrant CABG. At 6-month follow-up, the mean left ventricular ejection fraction increased from 0.61 to 0.65 in Tc-PPI-negative patients (p = 0.01), but not in perioperative patients with AMI.

  10. Formation of pyrophosphate-like adducts from nerve agents sarin, soman and cyclosarin in phosphate buffer: implications for analytical and toxicological investigations.

    Science.gov (United States)

    Gäb, Jürgen; John, Harald; Blum, Marc-Michael

    2011-01-15

    Phosphate buffer is frequently used in biological, biochemical and biomedical applications especially when pH is to be controlled around the physiological value of 7.4. One of the prerequisites of a buffer compound among good buffering capacity and pH stability over time is its non-reactivity with other constituents of the solution. This is especially important for quantitative analytical or toxicological assays. Previous work has identified a number of amino alcohol buffers like TRIS to react with G-type nerve agents sarin, soman and cyclosarin to form stable phosphonic diesters. In case of phosphate buffer we were able to confirm not only the rapid hydrolysis of these agents to the respective alkyl methylphosphonates but also the formation of substantial amounts of pyrophosphate-like adducts (phosphorylated methylphosphonates), which very slowly hydrolyzed following zero-order kinetics. This led to a complex mixture of phosphorus containing species with changing concentrations over time. We identified the molecular structure of these buffer adducts using 1D ¹H-³¹P HSQC NMR and LC-ESI-MS/MS techniques. Reaction rates of adduct formation are fast enough to compete with hydrolysis in aqueous solution and to yield substantial amounts of buffer adduct over the course of just a couple of minutes. Possible reaction mechanisms are discussed with respect to the formation and subsequent hydrolysis of the pyrophosphate-like compounds as well as the increased rate of hydrolysis of the nerve agent to the corresponding alkyl methylphosphonates. In summary, the use of phosphate buffer for the development of new assays with sarin, soman and cyclosarin is discouraged. Already existing protocols should be carefully reexamined on an individual basis.

  11. Eight years of follow-up after laminectomy of calcium pyrophosphate crystal deposition in the cervical yellow ligament of patient with Coffin–Lowry syndrome

    Science.gov (United States)

    Morino, Tadao; Ogata, Tadanori; Horiuchi, Hideki; Yamaoka, Shintaro; Fukuda, Mitsumasa; Miura, Hiromasa

    2016-01-01

    Abstract Background: We report 8 years of follow-up after decompression to treat cervical myelopathy in a patient with Coffin–Lowry syndrome (CLS). CLS is a rare X-linked semidominant syndrome associated with growth and psychomotor retardation, general hypotonia, and skeletal abnormalities. In this patient, the spinal cord was compressed by calcium pyrophosphate crystal deposition in the cervical yellow ligament (YL). To date, only 1 report has described clinical features after surgery for calcified cervical YL in CLS. Methods: A 15-year-old male with tetraplegia secondary to compression of the cervical spinal cord induced by a hypoplastic posterior arch of C1 and calcification of the YL from C2 to C7 was treated surgically with laminectomy from C1 to C7. The patient's history, clinical examination, imaging findings, and treatment are reported. The patient was incapable of speech because of mental retardation, so he could not describe his symptoms. Gait disturbance worsened over the 2 months before admission to our hospital. At admission, the patient could not move his extremities, and tendon reflexes of the upper and lower extremities were significantly increased. Computed tomography of the cervical spine showed YL calcification from C2 to C7. Magnetic resonance imaging showed consecutive compression of the cervical spinal cord. We diagnosed quadriplegia secondary to cervical cord damage and performed emergency surgery. Results: During C1–C7 laminectomy, YL calcification in C2–C7 was observed. The calcification was confirmed as calcium pyrophosphate by crystal analysis. Quadriplegia gradually resolved, and almost disappeared by 2 weeks after the operation. Cervical hyperlordosis was observed in radiographs starting from 1 month after the operation, but it has not progressed and is not associated with any symptoms. Conclusions: The efficacy of decompression continued, and no postoperative complications have occurred during at least 8 years of follow-up. PMID

  12. Isolation and characterization of Chinese standard fulvic acid sub-fractions separated from forest soil by stepwise elution with pyrophosphate buffer.

    Science.gov (United States)

    Bai, Yingchen; Wu, Fengchang; Xing, Baoshan; Meng, Wei; Shi, Guolan; Ma, Yan; Giesy, John P

    2015-03-04

    XAD-8 adsorption technique coupled with stepwise elution using pyrophosphate buffers with initial pH values of 3, 5, 7, 9, and 13 was developed to isolate Chinese standard fulvic acid (FA) and then separated the FA into five sub-fractions: FApH3, FApH5, FApH7, FApH9 and FApH13, respectively. Mass percentages of FApH3-FApH13 decreased from 42% to 2.5%, and the recovery ratios ranged from 99.0% to 99.5%. Earlier eluting sub-fractions contained greater proportions of carboxylic groups with greater polarity and molecular mass, and later eluting sub-fractions had greater phenolic and aliphatic content. Protein-like components, as well as amorphous and crystalline poly(methylene)-containing components were enriched using neutral and basic buffers. Three main mechanisms likely affect stepwise elution of humic components from XAD-8 resin with pyrophosphate buffers including: 1) the carboxylic-rich sub-fractions are deprotonated at lower pH values and eluted earlier, while phenolic-rich sub-fractions are deprotonated at greater pH values and eluted later. 2) protein or protein-like components can be desorbed and eluted by use of stepwise elution as progressively greater pH values exceed their isoelectric points. 3) size exclusion affects elution of FA sub-fractions. Successful isolation of FA sub-fractions will benefit exploration of the origin, structure, evolution and the investigation of interactions with environmental contaminants.

  13. Targeting Protein Prenylation in Progeria

    Science.gov (United States)

    Young, Stephen G.; Yang, Shao H.; Davies, Brandon S. J.; Jung, Hea-Jin; Fong, Loren G.

    2013-01-01

    A clinical trial of a protein farnesyltransferase inhibitor (lonafarnib) for the treatment of Hutchinson-Gilford progeria syndrome (HGPS) was recently completed. Here, we discuss the mutation that causes HGPS, the rationale for inhibiting protein farnesyltransferase, the potential limitations of this therapeutic approach, and new potential strategies for treating the disease. PMID:23390246

  14. Targeting Protein Prenylation in Progeria

    OpenAIRE

    Young, Stephen G.; Yang, Shao H.; Davies, Brandon S.J.; Jung, Hea-Jin; Fong, Loren G.

    2013-01-01

    A clinical trial of a protein farnesyltransferase inhibitor (lonafarnib) for the treatment of Hutchinson-Gilford progeria syndrome (HGPS) was recently completed. Here, we discuss the mutation that causes HGPS, the rationale for inhibiting protein farnesyltransferase, the potential limitations of this therapeutic approach, and new potential strategies for treating the disease.

  15. Targeting protein prenylation in progeria.

    Science.gov (United States)

    Young, Stephen G; Yang, Shao H; Davies, Brandon S J; Jung, Hea-Jin; Fong, Loren G

    2013-02-06

    A clinical trial of a protein farnesyltransferase inhibitor (lonafarnib) for the treatment of Hutchinson-Gilford progeria syndrome (HGPS) was recently completed. Here, we discuss the mutation that causes HGPS, the rationale for inhibiting protein farnesyltransferase, the potential limitations of this therapeutic approach, and new potential strategies for treating the disease.

  16. [Infectious hepatitis. I. Presence of HBs antigen].

    Science.gov (United States)

    Calderón, E; Ridaura, C; Legorreta, J; Gómez, D; Ruiz, M; Kassian, A

    1975-01-01

    A prospective study in 268 patients of different pediatric ages affected with icteric hepatitis is presented, with a longitudinal follow-up of one year minimum. Different types of clinical evolution are described and related to the presence of HBs antigen. In 34 of the 268 patients HBs antigen was positive; in 20 of 28 patients with acute and long evolution, positivity of the antigen was transitory with an average of 46 days; in the remaining 8 of 28 patients it extended from 6 months to less than 2 years. The presence of HBs antigen is a risk that may be correlated with the tendency to extend the prolonged.

  17. [Antigenic relationships between Debaryomyces strains (author's transl)].

    Science.gov (United States)

    Aksoycan, N

    1980-01-01

    The results of the agglutinations between homologous and heterologous Debaryomyces strains and their agglutinating sera are shown in table I. According to these findings, D. hansenii and D. marama are antigenically different from other Debaryomyces strains in this genus. In a previous study Aksoycan et al. have shown a common antigenic factor between D. hansenii, D. marama strains and Salmonella 0:7 antigen. This factor was not present in other six strains of Debaryomyces. These results also show that D. tamarii does not have any antigenic relationship with the other seven species of Debaryomyces in this genus.

  18. Blastogenic response of human lymphocytes to early antigen(s) of human cytomegalovirus.

    OpenAIRE

    Waner, J L; Kong, N; Biano, S

    1983-01-01

    The lymphocytes of asymptomatic, seropositive donors demonstrated blastogenic responses to early antigens of human cytomegalovirus whether or not antibodies to early antigens were detectable. The lymphocytes of six of nine patients with active cytomegalovirus infections gave stimulation indexes of greater than or equal to 2.00 with antigens of productively infected cells, whereas only two patients demonstrated comparable stimulation indexes with early antigens. Four patients with stimulation ...

  19. Blastogenic response of human lymphocytes to early antigen(s) of human cytomegalovirus.

    OpenAIRE

    Waner, J L; Kong, N; Biano, S

    1983-01-01

    The lymphocytes of asymptomatic, seropositive donors demonstrated blastogenic responses to early antigens of human cytomegalovirus whether or not antibodies to early antigens were detectable. The lymphocytes of six of nine patients with active cytomegalovirus infections gave stimulation indexes of greater than or equal to 2.00 with antigens of productively infected cells, whereas only two patients demonstrated comparable stimulation indexes with early antigens. Four patients with stimulation ...

  20. A computational framework for influenza antigenic cartography.

    Directory of Open Access Journals (Sweden)

    Zhipeng Cai

    Full Text Available Influenza viruses have been responsible for large losses of lives around the world and continue to present a great public health challenge. Antigenic characterization based on hemagglutination inhibition (HI assay is one of the routine procedures for influenza vaccine strain selection. However, HI assay is only a crude experiment reflecting the antigenic correlations among testing antigens (viruses and reference antisera (antibodies. Moreover, antigenic characterization is usually based on more than one HI dataset. The combination of multiple datasets results in an incomplete HI matrix with many unobserved entries. This paper proposes a new computational framework for constructing an influenza antigenic cartography from this incomplete matrix, which we refer to as Matrix Completion-Multidimensional Scaling (MC-MDS. In this approach, we first reconstruct the HI matrices with viruses and antibodies using low-rank matrix completion, and then generate the two-dimensional antigenic cartography using multidimensional scaling. Moreover, for influenza HI tables with herd immunity effect (such as those from Human influenza viruses, we propose a temporal model to reduce the inherent temporal bias of HI tables caused by herd immunity. By applying our method in HI datasets containing H3N2 influenza A viruses isolated from 1968 to 2003, we identified eleven clusters of antigenic variants, representing all major antigenic drift events in these 36 years. Our results showed that both the completed HI matrix and the antigenic cartography obtained via MC-MDS are useful in identifying influenza antigenic variants and thus can be used to facilitate influenza vaccine strain selection. The webserver is available at http://sysbio.cvm.msstate.edu/AntigenMap.

  1. A computational framework for influenza antigenic cartography.

    Science.gov (United States)

    Cai, Zhipeng; Zhang, Tong; Wan, Xiu-Feng

    2010-10-07

    Influenza viruses have been responsible for large losses of lives around the world and continue to present a great public health challenge. Antigenic characterization based on hemagglutination inhibition (HI) assay is one of the routine procedures for influenza vaccine strain selection. However, HI assay is only a crude experiment reflecting the antigenic correlations among testing antigens (viruses) and reference antisera (antibodies). Moreover, antigenic characterization is usually based on more than one HI dataset. The combination of multiple datasets results in an incomplete HI matrix with many unobserved entries. This paper proposes a new computational framework for constructing an influenza antigenic cartography from this incomplete matrix, which we refer to as Matrix Completion-Multidimensional Scaling (MC-MDS). In this approach, we first reconstruct the HI matrices with viruses and antibodies using low-rank matrix completion, and then generate the two-dimensional antigenic cartography using multidimensional scaling. Moreover, for influenza HI tables with herd immunity effect (such as those from Human influenza viruses), we propose a temporal model to reduce the inherent temporal bias of HI tables caused by herd immunity. By applying our method in HI datasets containing H3N2 influenza A viruses isolated from 1968 to 2003, we identified eleven clusters of antigenic variants, representing all major antigenic drift events in these 36 years. Our results showed that both the completed HI matrix and the antigenic cartography obtained via MC-MDS are useful in identifying influenza antigenic variants and thus can be used to facilitate influenza vaccine strain selection. The webserver is available at http://sysbio.cvm.msstate.edu/AntigenMap.

  2. Antigen/Antibody Analyses in Leishmaniasis.

    Science.gov (United States)

    1983-09-01

    antibodies in human sera with antigens of protozoan parasites . It was found that enzyme substrate reactions had distinct advantages over typical...autoradiographic procedures. Analyses of various sera identified a number of antigens of protozoan parasites which may be useful in discriminating infections

  3. Virosomes for antigen and DNA delivery

    NARCIS (Netherlands)

    Daemen, T; de Mare, A; Bungener, L; de Jonge, J; Huckriede, A; Wilschut, J

    2005-01-01

    Specific targeting and delivery as well as the display of antigens on the surface of professional antigen-presenting cells (APCs) are key issues in the design and development of new-generation vaccines aimed at the induction of both humoral and cell-mediated immunity. Prophylactic vaccination agains

  4. Protein antigen delivery by gene gun-mediated epidermal antigen incorporation (EAI).

    Science.gov (United States)

    Scheiblhofer, Sandra; Ritter, Uwe; Thalhamer, Josef; Weiss, Richard

    2013-01-01

    The gene gun technology can not only be employed for efficient transfer of gene vaccines into upper layers of the skin, but also for application of protein antigens. As a tissue rich in professional antigen presenting cells, the skin represents an attractive target for immunizations. In this chapter we present a method for delivery of the model antigen ovalbumin into the skin of mice termed epidermal antigen incorporation and describe in detail how antigen-specific proliferation in draining lymph nodes can be followed by flow cytometry.

  5. Tumor antigens as related to pancreatic cancer.

    Science.gov (United States)

    Chu, T M; Holyoke, E D; Douglass, H O

    1980-01-01

    Data are presented suggesting the presence of pancreas tumor-associated antigens. Slow progress has been made during the past few years in the identification of pancreatic tumor antigens that may be of clinical usefulness and it seems unlikely that many of the practical problems now being faced in identification and isolation of these antigens and in development of a specific, sensitive assay will be solved by conventional immunochemical approaches. The study of antigen and/or antibody purified from immune complexes in the host and the application of leukocyte adherence inhibition techniques to immunodiagnosis of pancreatic cancer are among the new approaches that may provide effective alternatives in the study of pancreatic tumor antigens.

  6. Up-regulated expression of cartilage intermediate-layer protein and ANK in articular hyaline cartilage from patients with calcium pyrophosphate dihydrate crystal deposition disease.

    Science.gov (United States)

    Hirose, Jun; Ryan, Lawrence M; Masuda, Ikuko

    2002-12-01

    Excess accumulation of extracellular inorganic pyrophosphate (ePPi) in aged human cartilage is crucial in calcium pyrophosphate dihydrate (CPPD) crystal formation in cartilage matrix. Two sources of ePPi are ePPi-generating ectoenzymes (NTPPPH) and extracellular transport of intracellular PPi by ANK. This study was undertaken to evaluate the role of NTPPPH and ANK in ePPi elaboration, by investigating expression of NTPPPH enzymes (cartilage intermediate-layer protein [CILP] and plasma cell membrane glycoprotein 1 [PC-1]) and ANK in human chondrocytes from osteoarthritic (OA) articular cartilage containing CPPD crystals and without crystals. Chondrocytes were harvested from knee cartilage at the time of arthroplasty (OA with CPPD crystals [CPPD], n = 8; OA without crystals [OA], n = 10). Normal adult human chondrocytes (n = 1) were used as a control. Chondrocytes were cultured with transforming growth factor beta1 (TGFbeta1), which stimulates ePPi elaboration, and/or insulin-like growth factor 1 (IGF-1), which inhibits ePPi elaboration. NTPPPH and ePPi were measured in the media at 48 hours. Media CILP, PC-1, and ANK were determined by dot-immunoblot analysis. Chondrocyte messenger RNA (mRNA) was extracted for reverse transcriptase-polymerase chain reaction to study expression of mRNA for CILP, PC-1, and ANK. NTPPPH and ANK mRNA and protein were also studied in fresh frozen cartilage. Basal ePPi elaboration and NTPPPH activity in conditioned media from CPPD chondrocytes were elevated compared with normal chondrocytes, and tended to be higher compared with OA chondrocytes. Basal expression of mRNA for CILP (chondrocytes) and ANK (cartilage) was higher in both CPPD chondrocytes and CPPD cartilage extract than in OA or normal samples. PC-1 mRNA was less abundant in CPPD chondrocytes and cartilage extract than in OA chondrocytes and extract, although the difference was not significant. CILP, PC-1, and ANK protein levels were similar in CPPD, OA, and normal chondrocytes

  7. Antigenic variation: Molecular and genetic mechanisms of relapsing disease

    Energy Technology Data Exchange (ETDEWEB)

    Cruse, J.M.; Lewis, R.E.

    1987-01-01

    This book contains 10 chapters. They are: Contemporary Concepts of Antigenic Variation; Antigenic Variation in the Influenza Viruses; Mechanisms of Escape of Visna Lentiviruses from Immunological Control; A Review of Antigenic Variation by the Equine Infectious Anemia Virus; Biologic and Molecular Variations in AIDS Retrovirus Isolates; Rabies Virus Infection: Genetic Mutations and the Impact on Viral Pathogenicity and Immunity; Immunobiology of Relapsing Fever; Antigenic Variation in African Trypanosomes; Antigenic Variation and Antigenic Diversity in Malaria; and Mechanisms of Immune Evasion in Schistosomiasis.

  8. Human seroreactivity to gut microbiota antigens.

    Science.gov (United States)

    Christmann, Benjamin S; Abrahamsson, Thomas R; Bernstein, Charles N; Duck, L Wayne; Mannon, Peter J; Berg, Göran; Björkstén, Bengt; Jenmalm, Maria C; Elson, Charles O

    2015-11-01

    Although immune responses directed against antigens from the intestinal microbiota are observed in certain diseases, the normal human adaptive immune response to intestinal microbiota is poorly defined. Our goal was to assess the adaptive immune response to the intestinal microbiota present in 143 healthy adults and compare this response with the response observed in 52 children and their mothers at risk of having allergic disease. Human serum was collected from adults and children followed from birth to 7 years of age, and the serum IgG response to a panel of intestinal microbiota antigens was assessed by using a novel protein microarray. Nearly every subject tested, regardless of health status, had serum IgG that recognized a common set of antigens. Seroreactivity to the panel of antigens was significantly lower in atopic adults. Healthy infants expressed the highest level of IgG seroreactivity to intestinal microbiota antigens. This adaptive response developed between 6 and 12 months of age and peaked around 2 years of age. Low IgG responses to certain clusters of microbiota antigens during infancy were associated with allergy development during childhood. There is an observed perturbation of the adaptive response to antigens from the microbiota in allergic subjects. These perturbations are observable even in childhood, suggesting that optimal stimulation of the adaptive immune system by the microbiota might be needed to prevent certain immune-mediated diseases. Copyright © 2015 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

  9. Antigen clasping by two antigen-binding sites of an exceptionally specific antibody for histone methylation

    Science.gov (United States)

    Hattori, Takamitsu; Lai, Darson; Dementieva, Irina S.; Montaño, Sherwin P.; Kurosawa, Kohei; Zheng, Yupeng; Akin, Louesa R.; Świst-Rosowska, Kalina M.; Grzybowski, Adrian T.; Koide, Akiko; Krajewski, Krzysztof; Strahl, Brian D.; Kelleher, Neil L.; Ruthenburg, Alexander J.; Koide, Shohei

    2016-01-01

    Antibodies have a well-established modular architecture wherein the antigen-binding site residing in the antigen-binding fragment (Fab or Fv) is an autonomous and complete unit for antigen recognition. Here, we describe antibodies departing from this paradigm. We developed recombinant antibodies to trimethylated lysine residues on histone H3, important epigenetic marks and challenging targets for molecular recognition. Quantitative characterization demonstrated their exquisite specificity and high affinity, and they performed well in common epigenetics applications. Surprisingly, crystal structures and biophysical analyses revealed that two antigen-binding sites of these antibodies form a head-to-head dimer and cooperatively recognize the antigen in the dimer interface. This “antigen clasping” produced an expansive interface where trimethylated Lys bound to an unusually extensive aromatic cage in one Fab and the histone N terminus to a pocket in the other, thereby rationalizing the high specificity. A long-neck antibody format with a long linker between the antigen-binding module and the Fc region facilitated antigen clasping and achieved both high specificity and high potency. Antigen clasping substantially expands the paradigm of antibody–antigen recognition and suggests a strategy for developing extremely specific antibodies. PMID:26862167

  10. Demonstration of Antigenic Identity Between Purified Equine Infectious Anemia Virus and an Antigen Extracted from Infected Horse Spleen

    Science.gov (United States)

    Nakajima, Hideo; Norcross, Neil L.; Coggins, Leroy

    1972-01-01

    Antigenic relationship between purified equine infectious anemia (EIA) virus and spleen-derived antigen from EIA-infected horses was examined by immunodiffusion. Identical antigenicity of these two antigens has been proven because precipitation lines formed between the two antigens and EIA antiserum connected with each other. The results indicate that the antigenic substance derived from infected spleen is a component of EIA virus. Images PMID:4629262

  11. Preparation and Bioactivity Properties of a Novel Composite Membrane of Fructose Mediated β-Tricalcium Pyrophosphate/(Polyethylene Glycol/Chitosan for Guided Tissue Regeneration

    Directory of Open Access Journals (Sweden)

    Jian-Wen Wang

    2015-01-01

    Full Text Available A novel composite membrane of β-tricalcium pyrophosphate (β-TCP and fructose- (F- mediated chitosan/poly(ethylene glycol (CS/PEG was prepared by thermally induced phase separation technique. The prepared composite membranes were characterized using scanning electron microscopy (SEM and X-ray diffraction (XRD. The mechanical property, swelling, degradation, and cytotoxicity of the composite membranes were evaluated in vitro with respect to its potential for use as biodegradable guided tissue regeneration (GTR membrane. In vitro degradation tests showed the composite membrane with a controllable degradation rate when changing the β-TCP content. The incorporation of β-TCP granules also caused a significant enhancement of tensile strength. When β-TCP content is controlled to 50 wt%, homogeneous composite membranes with well mechanical property and enzymatic degradation rate can be obtained. Cytotoxicity assay demonstrates that the composite membranes were nontoxic and had very good cell compatibility. Most importantly, the release of calcium ions and glucosamine from the composite membranes was proved to increase the cell proliferation of NIH3T3. The results of this study have indicated that this novel F-β-TCP/CS/PEG composite can be a suitable material for GTR applications.

  12. Overexpression of erg20 gene encoding farnesyl pyrophosphate synthase has contrasting effects on activity of enzymes of the dolichyl and sterol branches of mevalonate pathway in Trichoderma reesei.

    Science.gov (United States)

    Piłsyk, Sebastian; Perlińska-Lenart, Urszula; Górka-Nieć, Wioletta; Graczyk, Sebastian; Antosiewicz, Beata; Zembek, Patrycja; Palamarczyk, Grażyna; Kruszewska, Joanna S

    2014-07-10

    The mevalonate pathway is the most diverse metabolic route resulting in the biosynthesis of at least 30,000 isoprenoid compounds, many of which, such as sterols or dolichols, are indispensable for living cells. In the filamentous fungus Trichoderma of major biotechnological interest isoprenoid metabolites are also involved in the biocontrol processes giving the mevalonate pathway an additional significance. On the other hand, little is known about genes coding for enzymes of the mevalonate pathway in Trichoderma. Here, we present cloning and functional analysis of the erg20 gene from Trichoderma reesei coding for farnesyl pyrophosphate (FPP) synthase (EC 2.5.1.10), an enzyme located at the branching point of the mevalonate pathway. Expression of the gene in a thermosensitive erg20-2 mutant of Saccharomyces cerevisiae impaired in the FPP synthase activity suppressed the thermosensitive phenotype. The same gene overexpressed in T. reesei significantly enhanced the FPP synthase activity and also stimulated the activity of cis-prenyltransferase, an enzyme of the dolichyl branch of the mevalonate pathway. Unexpectedly, the activity of squalene synthase from the other, sterol branch, was significantly decreased without, however, affecting ergosterol level.

  13. Significance of calcific valvular heart disease in /sup 99m/Tc pyrophosphate myocardial infarction scanning: radiographic, scintigraphic, and pathological correlation

    Energy Technology Data Exchange (ETDEWEB)

    Jengo, J.A.; Mena, I.; Joe, S.H.; Criley, J.M.

    1977-08-01

    Technetium-99m pyrophosphate (PP/sub i/) is currently considered the best scanning agent for the diagnosis of acute myocardial infarction. False-positive scans have been reported in association with unstable angina, alcoholic cardiomyopathy, and ventricular aneurysms. In this study, 86 percent of patients (12/14) with either calcific aortic or mitral valvular heart disease had positive PP/sub i/ cardiac scintiscans and the location of the PP/sub i/ uptake was limited to the calcific valve in all (9/9) of the patients who underwent valve replacement surgery. Six patients with valvular disease without radiologic evidence of calcium had negative PP/sub i/ heart images. Three of these patients had surgical valve replacement, and in none was there increased uptake in the resected valve. Seventy-five percent of the patients with calcified aortic valves had localization of the PP/sub i/ activity to the area of the aortic valve, whereas 50 percent of the patients with calcified mitral valves showed a diffuse pattern of uptake on the cardiac image. In vitro demonstration of increased radioactivity in surgically removed cardiac valves warrants the conclusion that Tc-99m PP/sub i/ is taken up by calcified heart valves. We conclude that while PP/sub i/ heart scanning is a sensitive indicator of acute myocardial infarction, false-positive scans can occur in the presence of calcific valvular disease, due to localization of PP/sub i/ in the calcified portion of the valve.

  14. Efficacy of a microencapsulated iron pyrophosphate-fortified fruit juice: a randomised, double-blind, placebo-controlled study in Spanish iron-deficient women.

    Science.gov (United States)

    Blanco-Rojo, Ruth; Pérez-Granados, Ana M; Toxqui, Laura; González-Vizcayno, Carmen; Delgado, Marco A; Vaquero, M Pilar

    2011-06-01

    Fe-deficiency anaemia is a worldwide health problem. We studied the influence of consuming an Fe-fortified fruit juice on Fe status in menstruating women. A randomised, double-blind, placebo-controlled study of 16 weeks of duration was performed. Subjects were randomised into two groups: the P group (n 58) or the F group (n 64), and consumed, as a supplement to their usual diet, 500 ml/d of a placebo fruit juice or an Fe-fortified fruit juice, respectively. The Fe-fortified fruit juice, containing microencapsulated iron pyrophosphate, provided 18 mg Fe/d (100 % of the RDA). At baseline and monthly, dietary intake, body weight and Fe parameters were determined: total erythrocytes, haematocrit, mean corpuscular volume (MCV), red blood cell distribution width (RDW), Hb, serum Fe, serum ferritin, serum transferrin, transferrin saturation, soluble transferrin receptor (sTfR) and zinc protoporphyrin (ZnPP). The fruit juice consumption involved increased intake of carbohydrates and vitamin C, and increased BMI within normal limits. Ferritin was higher in the F group after week 4 (P fruit juice improves Fe status and may be used to prevent Fe-deficiency anaemia.

  15. Promotional Effect of Bismuth as Dopant in Bi-Doped Vanadyl Pyrophosphate Catalysts for Selective Oxidation of n-Butane to Maleic Anhydride

    Institute of Scientific and Technical Information of China (English)

    Y.H.Taufiq-Yap; Y.Kamiya; K.P.Tan

    2006-01-01

    Bismuth-promoted (1% and 3%) vanadyl pyrophosphate catalysts were prepared by refluxing creased the surface area and lowered the overall V oxidation state. Profiles of temperature programmed reduction (TPR) in H2 show a significant shift of the maxima of major reduction peaks to lower temperatures for the Bi-promoted catalysts. A new peak was also observed at the low temperature region for the catalyst with 3% of Bi dopant. The addition of Bi also increased the total amount of oxygen removed from the catalysts. The reduction pattern and reactivity information provide fundamental insight into the catalytic properties of the catalysts. Bi-promoted catalysts were found to be highly active (71% and 81%conversion for 1% and 3% Bi promoted catalysts, respectively, at 703 K), as compared to the unpromoted material (47% conversion). The higher activity of the Bi-promoted catalysts is due to that these catalysts possess highly active and labile lattice oxygen. The better catalytic performance can also be attributed to the larger surface area.

  16. Water-insoluble material from apple pomace makes changes in intracellular NAD⁺/NADH ratio and pyrophosphate content and stimulates fermentative production of hydrogen.

    Science.gov (United States)

    Sato, Osamu; Suzuki, Yuma; Sato, Yuki; Sasaki, Shinsuke; Sonoki, Tomonori

    2015-05-01

    Apple pomace is one of the major agricultural residues in Aomori prefecture, Japan, and it would be useful to develop effective applications for it. As apple pomace contains easily fermentable sugars such as glucose, fructose and sucrose, it can be used as a feedstock for the fermentation of fuels and chemicals. We previously isolated a new hydrogen-producing bacterium, Clostridium beijerinckii HU-1, which could produce H2 at a production rate of 14.5 mmol of H2/L/h in a fed-batch culture at 37 °C, pH 6.0. In this work we found that the HU-1 strain produces H2 at an approximately 20% greater rate when the fermentation medium contains the water-insoluble material from apple pomace. The water-insoluble material from apple pomace caused a metabolic shift that stimulated H2 production. HU-1 showed a decrease of lactate production, which consumes NADH, accompanied by an increase of the intracellular pyrophosphate content, which is an inhibitor of lactate dehydrogenase. The intracellular NAD(+)/NADH ratios of HU-1 during H2 fermentation were maintained in a more reductive state than those observed without the addition of the water insoluble material. To correct the abnormal intracellular redox balance, caused by the repression of lactate production, H2 production with NADH oxidation must be stimulated.

  17. Pyrophosphate sensing by a fluorescent Zn2+ bound triazole linked imino-thiophenyl conjugate of calix[4]arene in HEPES buffer medium: spectroscopy, microscopy, and cellular studies.

    Science.gov (United States)

    Pathak, Rakesh K; Tabbasum, Khatija; Rai, Ankit; Panda, Dulal; Rao, Chebrolu P

    2012-06-05

    An in situ prepared Zn(2+) complex of triazole linked imino-thiophenyl conjugate of calix[4]arene, [ZnL], was demonstrated to be highly fluorescent in HEPES buffer solution. [ZnL] has been used as a chemo-sensing ensemble for the recognition of phosphates in general and pyrophosphates in particular among the eighteen different anions studied. The chemo-sensing behavior of the [ZnL] has been demonstrated through fluorescence, absorption, visual fluorescent color changes, ESI MS, and (1)H NMR titrations. Variations in the microstructural features of L, its zinc complex and the complex upon addition of PPi have been demonstrated through atomic force microscopy and transmission electron microscopy. Such studies have been extended to see the permeability of the conjugate into the HeLa cells by fluorescence microscopy. In accession, a reversible "write-read-erase-read" logic gate property of L has been demonstrated through a feedback loop in the presence of Zn(2+) and PPi.

  18. Naked-eye sensitive detection of alkaline phosphatase (ALP) and pyrophosphate (PPi) based on a horseradish peroxidase catalytic colorimetric system with Cu(ii).

    Science.gov (United States)

    Shi, Dongmin; Sun, Yue; Lin, Lin; Shi, Chunjun; Wang, Guangfeng; Zhang, Xiaojun

    2016-10-07

    In this paper, a novel colorimetric method for the detection of alkaline phosphatase (ALP) and pyrophosphate (PPi) was designed based on a Cu(2+)-horseradish peroxidase (HRP)-3,3',5,5'-tetra-methylbenzidine (TMB)-H2O2 system. In the presence of ALP, l-ascorbic acid-2-phosphate (AAP) could be hydrolyzed to ascorbic acid which could reduce Cu(2+) to Cu(+) to inhibit the enzymatic activity of HRP in the colorimetric system. The change in absorbance was found to be proportional to the ALP concentration with a linear detection range and a limit of detection of 5.4 mU mL(-1). In the presence of PPi, because Cu(2+) was chelated by PPi, the conversion of Cu(ii) by AA was effectively inhibited. The color of the HRP-TMB-H2O2 system with Cu(2+) showed blue. The HRP-TMB-H2O2 system with the Cu(2+) colorimetric system could also detect PPi with a satisfying result. In summary, this method possesses sensitivity, reproducibility, and cost-effectiveness without labelling and separation and the use of a colorimetric method is more in line with the requirements of on-site detection and green chemistry.

  19. Foraminal deposition of calcium pyrophosphate dihydrate crystals in the thoracic spine: possible relationship with disc herniation and implications for surgical planning. Report of two cases.

    Science.gov (United States)

    Paolini, Sergio; Ciappetta, Pasquale; Guiducci, Antonio; Principi, Massimo; Missori, Paolo; Delfini, Roberto

    2005-01-01

    The authors report two cases of nodular calcium pyrophosphate dihydrate (CPPD) crystal deposition close to the thoracic neural foramen, which caused chronic radiculopathy. Preoperatively, the lesions were interpreted as calcified disc herniations. Both patients underwent surgery in which an extended transfacet pedicle-sparing approach was used. Incision of the posterior longitudinal ligament released soft degenerated material. In both cases, histological examination showed abundant degenerative debris along with CPPD crystals. Spinal CPPD deposition is a comparatively rare disease that almost invariably involves the posterior aspect of the spinal canal, typically the ligamentum flavum. The exceptional foraminal location of the lesions reported here, combined with the surgical findings, indicated that the CPPD crystals were deposited on a laterally herniated disc fragment. A distinctive feature in both cases was the soft consistency of the resected tissue. The consistency of the disc material and the location of the lesion in the axial plane (that is, median compared with lateral) are key factors in determining the optimal surgical approach to thoracic disc herniations. In describing consistency, terms such as "calcified" and "hard" have been used interchangeably in the literature. In the cases reported here, what appeared on computerized tomography and magnetic resonance imaging studies to be densely calcified lesions were shown intraoperatively to be soft herniations. The authors' experience underscores that not all densely calcified herniated discs are hard. Although detection of this discrepancy would have left surgical planning for the lateral disc herniations unchanged, it could have altered planning for centrally or centrolaterally located disc herniations.

  20. Minimum handling method for the analysis of phosphorous inhibitors of urolithiasis (pyrophosphate and phytic acid) in urine by SPE-ICP techniques.

    Science.gov (United States)

    Muñoz, Jose A; López-Mesas, Montserrat; Valiente, Manuel

    2010-01-25

    Pyrophosphate (PPi) and phytic acid (IP6) are natural phosphorous compounds with growing interest in the biomedical field due to their ability as potential inhibitors of urolithiasis among others. Existing methodologies for their evaluation show inconveniences mainly associated with sample treatment, matrix interferences and lack of resolution. The objective of the present work is the validation of a new method to determine both inhibitors in urine samples selectively and its application to the diagnosis of lithiasic patients. After urine purification by an off-line anion exchange solid phase extraction (SPE), based in an appropriate acidic elution gradient, the phosphorous compounds were analyzed by (31)P measurements by inductively coupled plasma mass spectrometry (ICP-MS) in the purified urine extracts. Linear range and limit of detection obtained were adequate for the analysis of the physiological amounts of the compounds in urine. The method was successfully applied to human urine samples, resulting in adequate accuracy and precision and allowing for the analysis of phosphorus inhibitors of urolithiasis in urine. The method simplicity and high sample throughput leads to a clear alternative to current determinations of the mentioned species in urine. Moreover, PPi and IP6 concentrations found in patients suffering from oxalocalcic urolithiasic were significantly lower than those for healthy controls, supporting the fact that the risk for oxalocalcic urolithiasis increases when urinary phosphorus inhibitors decrease. Thus, speciation of phosphorus inhibitors of urolithiasis in urine of stone formers can be performed, which is of unquestionable value in diagnostic, treatment and monitoring of urolithiasis.

  1. Ferrous ammonium phosphate (FeNH₄PO₄) as a new food fortificant: iron bioavailability compared to ferrous sulfate and ferric pyrophosphate from an instant milk drink.

    Science.gov (United States)

    Walczyk, Thomas; Kastenmayer, Peter; Storcksdieck Genannt Bonsmann, Stefan; Zeder, Christophe; Grathwohl, Dominik; Hurrell, Richard F

    2013-06-01

    The main purpose of this study was to establish bioavailability data in humans for the new (Fe) fortification compound ferrous ammonium phosphate (FAP), which was specially developed for fortification of difficult-to-fortify foods where soluble Fe compounds cannot be used due to their negative impact on product stability. A double-blind, randomized clinical trial with cross-over design was conducted to obtain bioavailability data for FAP in humans. In this trial, Fe absorption from FAP-fortified full-cream milk powder was compared to that from ferric pyrophosphate (FPP) and ferrous sulfate. Fe absorption was determined in 38 young women using the erythrocyte incorporation dual stable isotope technique (⁵⁷Fe, ⁵⁸Fe). Geometric mean Fe absorption from ferrous sulfate, FAP and FPP was 10.4, 7.4 and 3.3 %, respectively. Fe from FAP was significantly better absorbed from milk than Fe from FPP (p ferrous sulfate, which was used as water-soluble reference compound (p = 0.0002). Absorption ratios of FAP and FPP relative to ferrous sulfate as a measure of relative bioavailability were 0.71 and 0.32, respectively. The results of the present studies show that replacing FPP with FAP in full-cream milk could significantly improve iron bioavailability.

  2. Single- and repeated-dose oral toxicity studies of citicoline free-base (choline cytidine 5'-pyrophosphate) in Sprague-Dawley rats.

    Science.gov (United States)

    Schauss, A G; Somfai-Relle, S; Financsek, I; Glavits, R; Parent, S C; Endres, J R; Varga, T; Szücs, Z; Clewell, A

    2009-01-01

    The dietary supplement Citicoline free-base (choline cytidine 5'-pyrophosphate) was toxicologically evaluated in Sprague-Dawley rats using oral gavage. In an acute 14-day study, 2000 mg/kg was well tolerated. In a 90-day study, 100, 350, and 1000 mg/kg/day doses resulted in no mortality. In males, slight significant increases in serum creatinine (350 and 1000 mg/kg/day), and decreases in urine volume (all treated groups) were observed. In females, slight significant increases in total white blood cell and absolute lymphocyte counts (1000 mg/kg/day), and blood urea nitrogen (BUN) (100 and 350, but not 1000 mg/kg/day) were noted. A dose-related increase in renal tubular mineralization, without degenerative or inflammatory reaction, was found in females (all treated groups) and two males (1000 mg/kg/day). Renal mineralization in rats (especially females) is influenced by calcium:phosphorus ratios in the diet. A high level of citicoline consumption resulted in increased phosphorus intake in the rats, and likely explains this result.

  3. Platelet antigens and antibodies. Literature review

    Directory of Open Access Journals (Sweden)

    N. V. Mineeva

    2013-01-01

    Full Text Available Platelet antigens structure, role of platelet antibodies in the pathogenesis of various clinical conditions, characteristic of modern antibodies detection methods are presented in this article.

  4. Platelet antigens and antibodies. Literature review

    Directory of Open Access Journals (Sweden)

    N. V. Mineeva

    2014-07-01

    Full Text Available Platelet antigens structure, role of platelet antibodies in the pathogenesis of various clinical conditions, characteristic of modern antibodies detection methods are presented in this article.

  5. evaluation of an antigen-antibody

    African Journals Online (AJOL)

    GB

    BACKGROUND: Development of “combination” assays detecting in parallel, within a ... METHODS: We compared the Monolisa® HCV Antigen-Antibody Ultra (Bio-Rad Laboratories Limited, ... mediated response in these patients, a rapid viral.

  6. Antigen-specific memory B cell development.

    Science.gov (United States)

    McHeyzer-Williams, Louise J; McHeyzer-Williams, Michael G

    2005-01-01

    Helper T (Th) cell-regulated B cell immunity progresses in an ordered cascade of cellular development that culminates in the production of antigen-specific memory B cells. The recognition of peptide MHC class II complexes on activated antigen-presenting cells is critical for effective Th cell selection, clonal expansion, and effector Th cell function development (Phase I). Cognate effector Th cell-B cell interactions then promote the development of either short-lived plasma cells (PCs) or germinal centers (GCs) (Phase II). These GCs expand, diversify, and select high-affinity variants of antigen-specific B cells for entry into the long-lived memory B cell compartment (Phase III). Upon antigen rechallenge, memory B cells rapidly expand and differentiate into PCs under the cognate control of memory Th cells (Phase IV). We review the cellular and molecular regulators of this dynamic process with emphasis on the multiple memory B cell fates that develop in vivo.

  7. MAGE-A Antigens and Cancer Immunotherapy

    Science.gov (United States)

    Zajac, Paul; Schultz-Thater, Elke; Tornillo, Luigi; Sadowski, Charlotte; Trella, Emanuele; Mengus, Chantal; Iezzi, Giandomenica; Spagnoli, Giulio C.

    2017-01-01

    MAGE-A antigens are expressed in a variety of cancers of diverse histological origin and germinal cells. Due to their relatively high tumor specificity, they represent attractive targets for active specific and adoptive cancer immunotherapies. Here, we (i) review past and ongoing clinical studies targeting these antigens, (ii) analyze advantages and disadvantages of different therapeutic approaches, and (iii) discuss possible improvements in MAGE-A-specific immunotherapies. PMID:28337438

  8. In vivo induced antigen technology (IVIAT).

    Science.gov (United States)

    Rollins, Sean M; Peppercorn, Amanda; Hang, Long; Hillman, Jeffrey D; Calderwood, Stephen B; Handfield, Martin; Ryan, Edward T

    2005-01-01

    In vivo induced antigen technology (IVIAT) is a technique that identifies pathogen antigens that are immunogenic and expressed in vivo during human infection. IVIAT is complementary to other techniques that identify genes and their products expressed in vivo. Genes and gene pathways identified by IVIAT may play a role in virulence or pathogenesis during human infection, and may be appropriate for inclusion in therapeutic, vaccine or diagnostic applications.

  9. Presentation of antigen by B cells subsets. Pt. 2. The role of CD5 B cells in the presentation of antigen to antigen-specific T cells

    Energy Technology Data Exchange (ETDEWEB)

    Zimecki, Michal [Polish Academy of Sciences, Wroclaw (Poland). Institute of Immunology and Experimental Therapy; Kapp, Judith A. [Emory Univ., Atlanta, GA (United States). School of Medicine

    1994-12-31

    We demonstrate that peritoneal B cells have a much higher ability to present antigen to antigen-specific T cell lines splenic B cells. Presentation of antigen by B cells is abrogated or drastically reduced after removal of Lyb-5{sup +} cells from the population of splenic or peritoneal B cells. Peritoneal B cells, precultured for 7 days prior to the antigen presentation assay, retain their antigen presenting cell (APC) function. Enrichment for CD5{sup +} cells in the peritoneal B cell population results in a more effective antigen presentation. Lastly, stimulation of B cells via CD5 antigen, by treatment of cells with anti-CD5 antibodies or cross-linking of CD5 receptors, enhances APC function of these cells. The results indicate, both indirectly and directly, that CD5{sup +} B cells play a predominant role in the presentation of conventional antigens to antigen-specific T cells. (author). 30 refs, 6 tabs.

  10. Molecular Characterization of Soybean Pterocarpan 2-Dimethylallyltransferase in Glyceollin Biosynthesis: Local Gene and Whole-Genome Duplications of Prenyltransferase Genes Led to the Structural Diversity of Soybean Prenylated Isoflavonoids.

    Science.gov (United States)

    Yoneyama, Keisuke; Akashi, Tomoyoshi; Aoki, Toshio

    2016-12-01

    Soybean (Glycine max) accumulates several prenylated isoflavonoid phytoalexins, collectively referred to as glyceollins. Glyceollins (I, II, III, IV and V) possess modified pterocarpan skeletons with C5 moieties from dimethylallyl diphosphate, and they are commonly produced from (6aS, 11aS)-3,9,6a-trihydroxypterocarpan [(-)-glycinol]. The metabolic fate of (-)-glycinol is determined by the enzymatic introduction of a dimethylallyl group into C-4 or C-2, which is reportedly catalyzed by regiospecific prenyltransferases (PTs). 4-Dimethylallyl (-)-glycinol and 2-dimethylallyl (-)-glycinol are precursors of glyceollin I and other glyceollins, respectively. Although multiple genes encoding (-)-glycinol biosynthetic enzymes have been identified, those involved in the later steps of glyceollin formation mostly remain unidentified, except for (-)-glycinol 4-dimethylallyltransferase (G4DT), which is involved in glyceollin I biosynthesis. In this study, we identified four genes that encode isoflavonoid PTs, including (-)-glycinol 2-dimethylallyltransferase (G2DT), using homology-based in silico screening and biochemical characterization in yeast expression systems. Transcript analyses illustrated that changes in G2DT gene expression were correlated with the induction of glyceollins II, III, IV and V in elicitor-treated soybean cells and leaves, suggesting its involvement in glyceollin biosynthesis. Moreover, the genomic signatures of these PT genes revealed that G4DT and G2DT are paralogs derived from whole-genome duplications of the soybean genome, whereas other PT genes [isoflavone dimethylallyltransferase 1 (IDT1) and IDT2] were derived via local gene duplication on soybean chromosome 11.

  11. Expression and Antigenic Evaluation of VacA Antigenic Fragment of Helicobacter Pylori

    Directory of Open Access Journals (Sweden)

    Leila Hasanzadeh

    2013-07-01

    Full Text Available Objective(s: Helicobacter pylori, a human specific gastric pathogen is a causative agent of chronic active gastritis. The vacuolating cytotoxin (VacA is an effective virulence factor involved in gastric injury. The aim of this study was to construct a recombinant protein containing antigenic region of VacA gene and determine its antigenicity.   Materials and Methods: The antigenic region of VacA gene was detected by bioinformatics methods. The polymerase chain reaction method was used to amplify a highly antigenic region of VacA gene from chromosomal DNA of H. pylori. The eluted product was cloned into the prokaryotic expression vector pET32a. The target protein was expressed in the Escherichia coli BL21 (DE3 pLysS. The bacteria including pET32a-VacA plasmids were induced by IPTG. The antigenicity was finally studied by western blotting using sera of 15 H. pylori infected patients after purification. Results: Enzyme digestion analysis, PCR and DNA sequencing results showed that the target gene was inserted correctly into the recombinant vector. The expressed protein was purified successfully via affinity chromatography. Data indicated that antigenic region of VacA protein from Helicobacter pylori was recognized by all 15 patient’s sera. Conclusion : Our data showed that antigenic region of VacA protein can be expressed by in E. co.li. This protein was recognized by sera patients suffering from H. pylori infection. the recombinant protein has similar epitopes and close antigenic properties to the natural form of this antigen. Recombinant antigenic region of VacA protein also seems to be a promising antigen for protective and serologic diagnosis .

  12. Antigen cross-presentation of immune complexes.

    Science.gov (United States)

    Platzer, Barbara; Stout, Madeleine; Fiebiger, Edda

    2014-01-01

    The ability of dendritic cells (DCs) to cross-present tumor antigens has long been a focus of interest to physicians, as well as basic scientists, that aim to establish efficient cell-based cancer immune therapy. A prerequisite for exploiting this pathway for therapeutic purposes is a better understanding of the mechanisms that underlie the induction of tumor-specific cytotoxic T-lymphocyte (CTL) responses when initiated by DCs via cross-presentation. The ability of humans DC to perform cross-presentation is of utmost interest, as this cell type is a main target for cell-based immunotherapy in humans. The outcome of a cross-presentation event is guided by the nature of the antigen, the form of antigen uptake, and the subpopulation of DCs that performs presentation. Generally, CD8α(+) DCs are considered to be the most potent cross-presenting DCs. This paradigm, however, only applies to soluble antigens. During adaptive immune responses, immune complexes form when antibodies interact with their specific epitopes on soluble antigens. Immunoglobulin G (IgG) immune complexes target Fc-gamma receptors on DCs to shuttle exogenous antigens efficiently into the cross-presentation pathway. This receptor-mediated cross-presentation pathway is a well-described route for the induction of strong CD8(+) T cell responses. IgG-mediated cross-presentation is intriguing because it permits the CD8(-) DCs, which are commonly considered to be weak cross-presenters, to efficiently cross-present. Engaging multiple DC subtypes for cross-presentation might be a superior strategy to boost CTL responses in vivo. We here summarize our current understanding of how DCs use IgG-complexed antigens for the efficient induction of CTL responses. Because of its importance for human cell therapy, we also review the recent advances in the characterization of cross-presentation properties of human DC subsets.

  13. Seroreactivity of Salmonella-infected cattle herds against a fimbrial antigen in comparison with lipopolysaccharide antigens

    DEFF Research Database (Denmark)

    Hoorfar, Jeffrey; Lind, Peter; Bell, M.M.

    1996-01-01

    The IgG seroreaction of Salmonella-infected cattle herds against a fimbrial antigen (SEF14) was compared with that against lipopolysaccharide (LPS) antigens. Sera from 23 dairy herds (n = 205) from an island with no occurrence of salmonellosis, four herds (n = 303) with recent outbreaks of S...

  14. The antigenic relationship between Brettanomyces-Debaryomyces strains and the Salmonella cholerae-suis O antigen.

    Science.gov (United States)

    Aksoycan, N; Sağanak, I; Wells, G

    1978-01-01

    The immune sera for Brettanomyces lambicus, B. claussenii, Debaryomyces hansenii and D. marama agglutinated Salmonella cholerae-suis (0:6(2), 7). The immune serum for S. cholerae-suis agglutinated B. lambicus, B. clausenni, D. hansenii and D. marama. Absorption and agglutination cross-tested demonstrated common antigen factor(s) in the tested yeasts and Salmonella 0:7 antigen.

  15. Superexpression of tuberculosis antigens in plant leaves.

    Science.gov (United States)

    Dorokhov, Yuri L; Sheveleva, Anna A; Frolova, Olga Y; Komarova, Tatjana V; Zvereva, Anna S; Ivanov, Peter A; Atabekov, Joseph G

    2007-05-01

    Recent developments in genetic engineering allow the employment of plants as factories for 1/foreign protein production. Thus, tuberculosis (TB) ESAT6 antigen was expressed in different plant systems, but the level of vaccine protein accumulation was extremely low. We describe the technology for superexpression of TB vaccine proteins (Ag85B, ESAT6, and ESAT6:Ag85B fusion) in plant leaves which involves: (i) construction of tobacco mosaic virus-based vectors with the coat protein genes substituted by those for TB antigens; (ii) Agrobacterium-mediated delivery to plant leaf tissues of binary vectors containing the cDNA copy of the vector virus genome; and (iii) replication of virus vectors in plant cells under conditions suppressing the virus-induced gene silencing. This technology enables efficient production of the TB vaccine proteins in plants; in particular, the level of Ag85B antigen accumulation was not less than 800 mg/kg of fresh leaves. Expression of TB antigens in plant cells as His(6)-tagged proteins promoted their isolation and purification by Ni-NTA affinity chromatography. Deletion of transmembrane domains from Ag85B caused a dramatic increase in its intracellular stability. We propose that the strategy of TB antigens superproduction in a plant might be used as a basis for the creation of prophylactic and therapeutic vaccine against TB.

  16. Antigen presentation by MHC-dressed cells

    Directory of Open Access Journals (Sweden)

    Masafumi eNakayama

    2015-01-01

    Full Text Available Professional antigen presenting cells (APCs such as conventional dendritic cells (DCs process protein antigens to MHC-bound peptides and then present the peptide-MHC complexes to T cells. In addition to this canonical antigen presentation pathway, recent studies have revealed that DCs and non-APCs can acquire MHC class I (MHCI and/or MHC class II (MHCII from neighboring cells through a process of cell-cell contact-dependent membrane transfer called trogocytosis. These MHC-dressed cells subsequently activate or regulate T cells via the preformed antigen peptide-MHC complexes without requiring any further processing. In addition to trogocytosis, intercellular transfer of MHCI and MHCII can be mediated by secretion of membrane vesicles such as exosomes from APCs, generating MHC-dressed cells. This review focuses on the physiological role of antigen presentation by MHCI- or MHCII-dressed cells, and also discusses differences and similarities between trogocytosis and exosome-mediated transfer of MHC.

  17. Identification and characterization of SMU.244 encoding a putative undecaprenyl pyrophosphate phosphatase protein required for cell wall biosynthesis and bacitracin resistance in Streptococcus mutans.

    Science.gov (United States)

    Jalal, Naif; Tian, Xiao-Lin; Dong, Gaofeng; Upham, Jacqueline; Chen, Chao; Parcells, Madison; Li, Yung-Hua

    2015-09-01

    Streptococcus mutans in dental biofilms often faces life-threatening threats such as killing by antimicrobial molecules from competing species or from the host. The ability of S. mutans to cope with such threats is crucial for its survival and persistence in dental biofilms. By screening a transposon mutant library, we identified 11 transposon insertion mutants that were sensitive to bacitracin. Two of these mutants, XTn-01 and XTn-03, had an independent insertion in the same locus, SMU.244, which encoded a homologue of undecaprenyl pyrophosphate phosphatase (UppP). In this study, we describe the genetic and phenotypic characterization of SMU.244 in antibiotic resistance. The results revealed that deletion of SMU.244 results in a mutant (XTΔ244) that is highly sensitive to bacitracin, but confers more resistance to lactococcin G, a class IIb bacteriocin. Introduction of the intact SMU.244 into XTΔ244 in trans completely restores its resistance to bacitracin and the susceptibility to lactococcin G. The XTΔ244 was also defective in forming the WT biofilm, although its growth was not significantly affected. Using recombinant protein technology, we demonstrated that the SMU.244-encoded protein displays enzyme activity to catalyse dephosphorylation of the substrate. The lux transcriptional reporter assays showed that S. mutans maintains a moderate level of expression of SMU.244 in the absence of bacitracin, but bacitracin at sub-MICs can further induce its expression. We concluded that SMU.244 encodes an UppP protein that plays important roles in cell wall biosynthesis and bacitracin resistance in S. mutans. The results described here may further our understanding of the molecular mechanisms by which S. mutans copes with antibiotics such as bacitracin.

  18. Inhibition of lipid phosphate phosphatase activity by VPC32183 suppresses the ability of diacylglycerol pyrophosphate to activate ERK(1/2) MAP kinases.

    Science.gov (United States)

    Violet, Pierre-Christian; Billon-Denis, Emmanuelle; Robin, Philippe

    2012-11-01

    The lipidic metabolite, diacylglycerol pyrophosphate (DGPP), in its dioctanoyl form (DGPP 8:0), has been described as an antagonist for mammalian lysophosphatidic acid (LPA) receptors LPA1 and LPA3. In this study we show that DGPP 8:0 does not antagonize LPA dependent activation of ERK(1/2) MAP kinases but strongly stimulated them in various mammalian cell lines. LPA and DGPP 8:0 stimulation of ERK(1/2) occurred through different pathways. The DGPP 8:0 effect appeared to be dependent on PKC, Raf and MEK but was insensitive to pertussis toxin and did not involve G protein activation. Finally we showed that DGPP 8:0 effect on ERK(1/2) was dependent on its dephosphorylation by a phosphatase activity sharing lipid phosphate phosphatase properties. The inhibition of this phosphatase activity by VPC32183, a previously characterized LPA receptor antagonist, blocked the DGPP 8:0 effect on ERK(1/2) activation. Moreover, down-regulation of lipid phosphate phosphatase 1 (LPP1) expression by RNA interference technique also reduced DGPP 8:0-induced ERK(1/2) activation. Consistently, over expression of LPP1 in HEK293 cells increases DGPP 8:0 hydrolysis and this increased activity was inhibited by VPC32183. In conclusion, DGPP 8:0 does not exert its effect by acting on a G protein coupled receptor, but through its dephosphorylation by LPP1, generating dioctanoyl phosphatidic acid which in turn activates PKC. These results suggest that LPP1 could have a positive regulatory function on cellular signaling processes such as ERK(1/2) activation.

  19. Biodegradation behavior and cytotoxicity of the composite membrane composed of beta-dicalcium pyrophosphate and glucose mediated (polyethylene glycol/chitosan).

    Science.gov (United States)

    Wang, Jian Wen; Hon, Min Hsiung

    2004-02-01

    The purpose of this study is to prepare and evaluate the biodegradation behavior and cytotoxicity of a composite membrane, G-beta-DCP, combining beta-dicalcium pyrophosphate (beta-DCP) ceramic particles and glucose mediated chitosan-polyethylene glycol (PEG) membrane. The cytotoxicity of the G-beta-DCP was examined by the in vitro method of NIH 3T3 fibroblast cell culture. Extracts were obtained by soaking the G-beta-DCP composite in lysozyme containing phosphate buffer solution for 2, 7, 14, 21 and 28 days, respectively. The substances released from the G-beta-DCP composite were analyzed by gas chromatography-mass spectrometry (GC-MAS) and inductively coupled plasma atomic emission spectrometry (ICP-AES). The change in morphologies, chemical composition and crystal structure was examined by scanning electron microscopy (SEM) and X-ray diffraction pattern (XRD). The results of extracts cocultured with fibroblasts show that the growth of fibroblasts would increase for the extracts obtained from different beta-DCP feeding weight G-beta-DCP composites after soaking for 7 days. After further increasing the soaking time, the cell number still increases. It is found that the glucose amine and calcium are gradually released from the G-beta-DCP composites, which is considered to be nutritious for the growth of the fibroblast. The release rate of calcium ion and glucosamine concentration can be regulated by feeding the beta-DCP. The degradation behavior of G-beta-DCP composite is considered as an "onion degradation model" that the G-beta-DCP degrades from outer layer to inner layer. The developed material should have a great potential as a cell substrate in the field of tissue engineering.

  20. Purification and Structural and Kinetic Characterization of the Pyrophosphate:Fructose-6-Phosphate 1-Phosphotransferase from the Crassulacean Acid Metabolism Plant, Pineapple.

    Science.gov (United States)

    Tripodi, KEJ.; Podesta, F. E.

    1997-03-01

    Pyrphosphate-dependent phosphofructokinase (PFP) was purified to electrophoretic homogeneity from illuminated pineapple (Ananas comosus) leaves. The purified enzyme consists of a single subunit of 61.5 kD that is immunologically related to the potato tuber PFP [beta] subunit. The native form of PFP likely consists of a homodimer of 97.2 kD, as determined by gel filtration. PFP's glycolytic activity was strongly dependent on pH, displaying a maximum at pH 7.7 to 7.9. Gluconeogenic activity was relatively constant between pH 6.7 and 8.7. Activation by Fru-2,6-bisphosphate (Fru-2,6-P2) was dependent on assay pH. In the glycolytic direction, it activated about 10-fold at pH 6.7, but only 2-fold at pH 7.7. The gluconeogenic reaction was only weakly affected by Fru-2,6-P2. The true substrates for the PFP forward and reverse reactions were Fru-6-phosphate and Mg-pyrophosphate, and Fru-1,6-P2, orthophosphate, and Mg2+, respectively. The results suggest that pineapple PFP displays regulatory properties consistent with a pH-based regulation of its glycolytic activity, in which a decrease in cytosolic pH caused by nocturnal acidification during Crassulacean acid metabolism, which could curtail its activity, is compensated by a parallel increase in its sensitivity to Fru-2,6-P2. It is also evident that the [beta] subunit alone is sufficient to confer PFP with a high catalytic rate and the regulatory properties associated with activation by Fru-2,6-P2.

  1. Postoperative myocardial infarction documented by technetium pyrophosphate scan using single-photon emission computed tomography: Significance of intraoperative myocardial ischemia and hemodynamic control

    Energy Technology Data Exchange (ETDEWEB)

    Cheng, D.C.; Chung, F.; Burns, R.J.; Houston, P.L.; Feindel, C.M. (Toronto Hospital, Ontario (Canada))

    1989-12-01

    The aim of this prospective study was to document postoperative myocardial infarction (PMI) by technetium pyrophosphate scan using single-photon emission computed tomography (TcPPi-SPECT) in 28 patients undergoing elective coronary bypass grafting (CABG). The relationships of intraoperative electrocardiographic myocardial ischemia, hemodynamic responses, and pharmacological requirements to this incidence of PMI were correlated. Radionuclide cardioangiography and TcPPi-SPECT were performed 24 h preoperatively and 48 h postoperatively. A standard high-dose fentanyl anesthetic protocol was used. Twenty-five percent of elective CABG patients were complicated with PMI, as documented by TcPPi-SPECT with an infarcted mass of 38.0 +/- 5.5 g. No significant difference in demographic, preoperative right and left ventricular function, number of coronary vessels grafted, or aortic cross-clamp time was observed between the PMI and non-PMI groups. The distribution of patients using preoperative beta-adrenergic blocking drugs or calcium channel blocking drugs was found to have no correlation with the outcome of PMI. As well, no significant differences in hemodynamic changes or pharmacological requirements were observed in the PMI and non-PMI groups during prebypass or postbypass periods, indicating careful intraoperative control of hemodynamic indices did not prevent the outcome of PMI in these patients. However, the incidence of prebypass ischemia was 39.3% and significantly correlated with the outcome of positive TcPPi-SPECT, denoting a 3.9-fold increased risk of developing PMI. Prebypass ischemic changes in leads II and V5 were shown to correlate with increased CPK-MB release (P less than 0.05) and tends to occur more frequently with lateral myocardial infarction.

  2. The prevalence of chondrocalcinosis (CC) of the acromioclavicular (AC) joint on chest radiographs and correlation with calcium pyrophosphate dihydrate (CPPD) crystal deposition disease.

    Science.gov (United States)

    Parperis, Konstantinos; Carrera, Guillermo; Baynes, Keith; Mautz, Alan; Dubois, Melissa; Cerniglia, Ross; Ryan, Lawrence M

    2013-09-01

    Digital imaging combined with picture archiving and communication system (PACS) access allows detailed image retrieval and magnification. Calcium pyrophosphate dihydrate (CPPD) crystals preferentially deposit in fibrocartilages, the cartilage of the acromioclavicular (AC) joint being one such structure. We sought to determine if examination of the AC joints on magnified PACS imaging of chest films would be useful in identifying chondrocalcinosis (CC). Retrospective radiographic readings and chart reviews involving 1,920 patients aged 50 or more who had routine outpatient chest radiographs over a 4-month period were performed. Knee radiographs were available for comparison in 489 patients. Medical records were reviewed to abstract demographics, chest film reports, and diagnoses. AC joint CC was identified in 1.1 % (21/1,920) of consecutive chest films. Patients with AC joint CC were 75 years of age versus 65.4 in those without CC (p AC joint CC, and of these, five also had knee CC (83 %). Of the 483 without AC joint CC, 62 (12 %) had knee CC (p = 0.002). Patients with AC joint CC were more likely to have a recorded history of CPPD crystal deposition disease than those without AC joint CC (14 versus 1 %, p = 0.0017). The prevalence of AC joint CC increases with age and is associated with knee CC. A finding of AC joint CC should heighten suspicion of pseudogout or secondary osteoarthritis in appropriate clinical settings and, in a young patient, should alert the clinician to the possibility of an associated metabolic condition.

  3. Isopentenyl pyrophosphate activated CD56+ γδ T lymphocytes display potent anti-tumor activity towards human squamous cell carcinoma

    Science.gov (United States)

    Alexander, Alan A.Z.; Maniar, Amudhan; Cummings, Jean-Saville; Hebbeler, Andrew M.; Schulze, Dan H.; Gastman, Brian R.; Pauza, C. David; Strome, Scott E.; Chapoval, Andrei I.

    2008-01-01

    Purpose The expression of CD56, a natural killer (NK) cell-associated molecule, on αβ T lymphocytes correlates with their increased anti-tumor effector function. CD56 is also expressed on a subset of γδ T cells. However, anti-tumor effector functions of CD56+ γδ T cells are poorly characterized. Experimental design To investigate the potential effector role of CD56+ γδ T cells in tumor killing, we employed isopentenyl pyrophosphate (IPP) and IL-2 expanded γδ T cells from PBMC of healthy donors. Results Thirty to 70% of IPP+IL-2 expanded γδ T cells express CD56 on their surface. Interestingly, while both CD56+ and CD56− γδ T cells express comparable levels of receptors involved in the regulation of γδ T cell cytotoxicity (e.g. NKG2D and CD94) only CD56+ γδ T lymphocytes are capable of killing squamous cell carcinoma (SCC) and other solid tumor cell lines. This effect is likely mediated by the enhanced release of cytolytic granules, since CD56+ γδ T lymphocytes expressed higher levels of CD107a compared to CD56− controls, following exposure to tumor cell lines. Lysis of tumor cell lines is blocked by concanomycin A and a combination of anti-γδTCR + anti-NKG2D mAb, suggesting that the lytic activity of CD56+ γδ T cells involves the perforin-granzyme pathway and is mainly γδTCR/NKGD2 dependent. Importantly, CD56 expressing γδ T lymphocytes are resistant to Fas ligand and chemically induced apoptosis. Conclusions Our data indicate that CD56+ γδ T cells are potent anti-tumor effectors capable of killing SCC and may play an important therapeutic role in patients with head and neck cancer and other malignancies. PMID:18594005

  4. Antigenic typing Polish isolates of canine parvovirus

    Energy Technology Data Exchange (ETDEWEB)

    Mizak, B. [National Veterinary Research Institute, Pulawy (Poland); Plucienniczak, A. [Polish Academy ofd Sciences. Microbiology and Virology Center, Lodz (Poland)

    1995-12-31

    Polish strains of canine parvovirus isolated between 1982 and 1993 were examined to determine the extent to which the virus has evolved antigenically and genetically over eleven years. Two CPV isolates obtained in Warsaw in 1982 and Pulawy in 1993, were examined using monoclonal antibody typing, restriction analysis and sequencing VP-2 protein gene. Five other isolates from Warsaw and Pulawy were tested with the panel of monoclonal antibodies specific to CPV-2, CPV-2a and common for canine parvovirus, feline panleukopenia virus and milk enteritis virus. Results of the studies demonstrated that all isolates tested represented CPV-2a antigenic type. Rapid antigenic strain replacement recorded by Parrish and Senda in the U.S.A and Japan was not confirmed in Poland. (author). 30 refs, 2 tabs.

  5. Harnessing Dendritic Cells for Tumor Antigen Presentation

    Energy Technology Data Exchange (ETDEWEB)

    Nierkens, Stefan [Department of Tumor Immunology, Nijmegen Centre for Molecular Life Sciences, Radboud University Nijmegen Medical Centre, Geert Grooteplein 28, Nijmegen 6525 GA (Netherlands); Janssen, Edith M., E-mail: edith.janssen@cchmc.org [Division of Molecular Immunology, Cincinnati Children' s Hospital Research Foundation, University of Cincinnati College of Medicine, 3333 Burnet Avenue, Cincinnati, OH 45229 (United States)

    2011-04-26

    Dendritic cells (DC) are professional antigen presenting cells that are crucial for the induction of anti-tumor T cell responses. As a consequence, research has focused on the harnessing of DCs for therapeutic interventions. Although current strategies employing ex vivo-generated and tumor-antigen loaded DCs have been proven feasible, there are still many obstacles to overcome in order to improve clinical trial successes and offset the cost and complexity of customized cell therapy. This review focuses on one of these obstacles and a pivotal step for the priming of tumor-specific CD8{sup +} and CD4{sup +} T cells; the in vitro loading of DCs with tumor antigens.

  6. Ternary complex structures of human farnesyl pyrophosphate synthase bound with a novel inhibitor and secondary ligands provide insights into the molecular details of the enzyme’s active site closure

    Directory of Open Access Journals (Sweden)

    Park Jaeok

    2012-12-01

    Full Text Available Abstract Background Human farnesyl pyrophosphate synthase (FPPS controls intracellular levels of farnesyl pyrophosphate, which is essential for various biological processes. Bisphosphonate inhibitors of human FPPS are valuable therapeutics for the treatment of bone-resorption disorders and have also demonstrated efficacy in multiple tumor types. Inhibition of human FPPS by bisphosphonates in vivo is thought to involve closing of the enzyme’s C-terminal tail induced by the binding of the second substrate isopentenyl pyrophosphate (IPP. This conformational change, which occurs through a yet unclear mechanism, seals off the enzyme’s active site from the solvent environment and is essential for catalysis. The crystal structure of human FPPS in complex with a novel bisphosphonate YS0470 and in the absence of a second substrate showed partial ordering of the tail in the closed conformation. Results We have determined crystal structures of human FPPS in ternary complex with YS0470 and the secondary ligands inorganic phosphate (Pi, inorganic pyrophosphate (PPi, and IPP. Binding of PPi or IPP to the enzyme-inhibitor complex, but not that of Pi, resulted in full ordering of the C-terminal tail, which is most notably characterized by the anchoring of the R351 side chain to the main frame of the enzyme. Isothermal titration calorimetry experiments demonstrated that PPi binds more tightly to the enzyme-inhibitor complex than IPP, and differential scanning fluorometry experiments confirmed that Pi binding does not induce the tail ordering. Structure analysis identified a cascade of conformational changes required for the C-terminal tail rigidification involving Y349, F238, and Q242. The residues K57 and N59 upon PPi/IPP binding undergo subtler conformational changes, which may initiate this cascade. Conclusions In human FPPS, Y349 functions as a safety switch that prevents any futile C-terminal closure and is locked in the “off” position in the

  7. Properties of glycolipid-enriched membrane rafts in antigen presentation.

    Science.gov (United States)

    Rodgers, William; Smith, Kenneth

    2005-01-01

    Presentation of antigen to T cells represents one of the central events in the engagement of the immune system toward the defense of the host against pathogens. Accordingly, understanding the mechanisms by which antigen presentation occurs is critical toward our understanding the properties of host defense against foreign antigen, as well as insight into other features of the immune system, such as autoimmune disease. The entire antigen-presentation event is complex, and many features of it remain poorly understood. However, recent studies have provided evidence showing that glycolipid-enriched membrane rafts are important for efficient antigen presentation; the studies suggest that one such function of rafts is trafficking of antigen-MHC II complexes to the presentation site on the surface of the antigen-presenting cell. Here, we present a critical discussion of rafts and their proposed functions in antigen presentation. Emerging topics of rafts and antigen presentation that warrant further investigation are also highlighted.

  8. Antigenic variation of Streptococcus mutans colonizing gnotobiotic rats.

    Science.gov (United States)

    Bratthall, D; Gibbons, R J

    1975-12-01

    Strains of Streptococcus mutans representative of serotypes b and d exhibited antigenic variation in both the oral cavity and in the intestinal canal of gnotobiotic rats. Laboratory-maintained cultures did not vary. The antigenic alterations observed were: (i) loss of detectable levels of both weakly reacting "strain" antigens and the type antigen; (ii) decreased production of the type antigen; (ii) production of altered type antigen; and (iv) production of an antigen not possessed by the parent strain. Immunization of animals before monoinfection with S. mutans strain Bob-1 (serotype d) appeared to increase the rate of emergence of antigenically altered mutants in the intestinal canal, and more diversely altered isolates were obtained. Antigenic variation may account in part for the variation noted by several investigators in attempting to immunize animals against S. mutans-induced dental caries.

  9. Classification of human leukocyte antigen (HLA) supertypes

    DEFF Research Database (Denmark)

    Wang, Mingjun; Claesson, Mogens H

    2014-01-01

    Identification of new antigenic peptides, derived from infectious agents or cancer cells, which bind to human leukocyte antigen (HLA) class I and II molecules, is of importance for the development of new effective vaccines capable of activating the cellular arm of the immune response. However...... this complexity is to group thousands of different HLA molecules into several so-called HLA supertypes: a classification that refers to a group of HLA alleles with largely overlapping peptide binding specificities. In this chapter, we focus on the state-of-the-art classification of HLA supertypes including HLA...

  10. Serum levels of carcinoembryonic antigen and a tumor-extracted carcinoembryonic antigen-related antigen in cancer patients.

    Science.gov (United States)

    Shively, J E; Spayth, V; Chang, F F; Metter, G E; Klein, L; Presant, C A; Todd, C W

    1982-06-01

    Levels of carcinoembryonic antigen (CEA) and a tumor-extracted CEA-related antigen (TEX) were determined in sera from patients with carcinomas of the breast, colon, lung, head and neck, and a number of miscellaneous categories. The purpose of this study was to compare the levels of each antigen at various stages of malignant disease. Competitive radioimmunoassays developed in our laboratory were shown to be sufficiently specific to detect either of these two antigens independent of each other. The results indicate that: (a) with our specific assays, CEA was not significantly elevated in smoker controls, but TEX was elevated in 29% of smoker controls; (b) TEX was equivalent to CEA as a tumor marker for colonic cancer. TEX was better than CEA as a marker for lung cancer and, based on limited data, there is a possibility that TEX is a significantly better tumor marker than is CEA in early lung cancer; (c) TEX was superior to CEA as a tumor marker for breast and head and neck cancers; (d) there is a strong indication that serial determinations of TEX can be used as effectively as CEA in the monitoring of disease progress. These preliminary results must be confirmed by increasing the number of cancer patients and including nonmalignant disease controls.

  11. Antigen processing and remodeling of the endosomal pathway: requirements for antigen cross-presentation.

    Science.gov (United States)

    Compeer, Ewoud Bernardus; Flinsenberg, Thijs Willem Hendrik; van der Grein, Susanna Geertje; Boes, Marianne

    2012-01-01

    Cross-presentation of endocytosed antigen as peptide/class I major histocompatibility complex complexes plays a central role in the elicitation of CD8(+) T cell clones that mediate anti-viral and anti-tumor immune responses. While it has been clear that there are specific subsets of professional antigen presenting cells capable of antigen cross-presentation, identification of mechanisms involved is still ongoing. Especially amongst dendritic cells (DC), there are specialized subsets that are highly proficient at antigen cross-presentation. We here present a focused survey on the cell biological processes in the endosomal pathway that support antigen cross-presentation. This review highlights DC-intrinsic mechanisms that facilitate the cross-presentation of endocytosed antigen, including receptor-mediated uptake, maturation-induced endosomal sorting of membrane proteins, dynamic remodeling of endosomal structures and cell surface-directed endosomal trafficking. We will conclude with the description of pathogen-induced deviation of endosomal processing, and discuss how immune evasion strategies pertaining endosomal trafficking may preclude antigen cross-presentation.

  12. Antigen processing and remodeling of the endosomal pathway: requirements for antigen cross-presentation.

    Directory of Open Access Journals (Sweden)

    Ewoud Bernardus Compeer

    2012-03-01

    Full Text Available The cross-presentation of endocytosed antigen as peptide/class I MHC complexes plays a central role in the elicitation of CD8+ T cell clones that mediate anti-viral and anti-tumor immune responses. While it has been clear that there are specific subsets of professional antigen presenting cells (APC capable of antigen cross-presentation, description of mechanisms involved is still ongoing. Especially amongst dendritic cells (DC, there are specialized subsets that are highly proficient at antigen cross-presentation. We here present a focused survey on the cell biological processes in the endosomal pathway that support antigen cross-presentation. This review highlight DC-intrinsic mechanisms that facilitate the cross-presentation of endocytosed antigen, including receptor-mediated uptake, recycling and maturation including the sorting of membrane proteins, dynamic remodeling of endosomal structures and cell-surface directed endosomal trafficking. We will conclude with description of pathogen-induced deviation of endosomal processing, and discuss how immune evasion strategies pertaining endosomal trafficking may preclude antigen cross-presentation.

  13. Xanthohumol, a prenylated flavonoid contained in beer, prevents the induction of preneoplastic lesions and DNA damage in liver and colon induced by the heterocyclic aromatic amine amino-3-methyl-imidazo[4,5-f]quinoline (IQ)

    Energy Technology Data Exchange (ETDEWEB)

    Ferk, Franziska; Huber, Wolfgang W. [Institute of Cancer Research, Department of Medicine I, Medical University of Vienna, Borschkegasse 8a, A-1090 Vienna (Austria); Filipic, Metka [National Institute of Biology, Department of Genetic Toxicology and Cancer Biology, University of Ljubljana, 1000 Ljubljana (Slovenia); Bichler, Julia; Haslinger, Elisabeth; Misik, Miroslav; Nersesyan, Armen; Grasl-Kraupp, Bettina [Institute of Cancer Research, Department of Medicine I, Medical University of Vienna, Borschkegasse 8a, A-1090 Vienna (Austria); Zegura, Bojana [National Institute of Biology, Department of Genetic Toxicology and Cancer Biology, University of Ljubljana, 1000 Ljubljana (Slovenia); Knasmueller, Siegfried, E-mail: siegfried.knasmueller@meduniwien.ac.at [Institute of Cancer Research, Department of Medicine I, Medical University of Vienna, Borschkegasse 8a, A-1090 Vienna (Austria)

    2010-09-10

    Xanthohumol (XN) is a hop derived prenylated flavonoid contained in beer. Earlier findings indicated that it has promising chemopreventive properties and protects cells against DNA damage by carcinogens via inhibition of their activation. Furthermore, it was found that XN inhibits DNA synthesis and proliferation of cancer cells in vitro, inactivates oxygen radicals and induces apoptosis. Since evidence for its chemoprotective properties is restricted to results from in vitro experiments, we monitored the impact of XN on the formation of amino-3-methyl-imidazo[4,5-f]quinoline (IQ)-induced preneoplastic foci in livers and colons of rats (9/group). Additionally, we studied its effects on IQ-induced DNA damage in colonocytes and hepatocytes in single cell gel electrophoresis assays and on the activities of a panel of drug metabolising enzymes. Consumption of the drinking water supplemented with XN (71 {mu}g/kg b.w.) before and during carcinogen treatment led to a significant reduction of the number of GST-p{sup +} foci in the liver by 50% and also to a decrease of the foci area by 44%. DNA migration was decreased significantly in both, colon mucosa and liver cells, but no alterations of the activities of different phases I and II enzymes were found in hepatic tissue. Our findings indicate that XN protects against DNA damage and cancer induced by the cooked food mutagen. Since the effects were observed with low doses of XN which are reached after consumption of brews with high XN levels, our findings may be relevant for humans.

  14. A NEW SYNTHETIC FUNCTIONALIZED ANTIGEN CARRIER

    NARCIS (Netherlands)

    DRIJFHOUT, JW; BLOEMHOFF, W

    1991-01-01

    A new synthetic functionalized antigen carrier is described. It consists of a core of seven branched lysine residues, of which each of the four N-terminal lysine residues contains two N-(S-acetylmercaptoacetyl)-glutamyl residues. After removal of the protecting S-acetyl groups affording eight thiol

  15. Prostate-specific antigen (PSA) blood test

    Science.gov (United States)

    Prostate-specific antigen; Prostate cancer screening test; PSA ... special steps are needed to prepare for this test. ... Reasons for a PSA test: This test may be done to screen for prostate cancer. It is also used to follow people after prostate cancer ...

  16. STAINING OF VACCINIA ANTIGEN BY IMMUNOURANIUM TECHNIQUE,

    Science.gov (United States)

    An attempt to follow morphologically the development of vaccinia antigen in helium-lanthanum ( HeLa ) cells is reported. The conversion of rabbit...antisera to vaccinia virus and the preparation of vaccinia-infected HeLa cells for electron microscopy are described. With specific staining, viral

  17. HLA antigens and asthma in Greeks.

    Science.gov (United States)

    Apostolakis, J; Toumbis, M; Konstantopoulos, K; Kamaroulias, D; Anagnostakis, J; Georgoulias, V; Fessas, P; Zervas, J

    1996-04-01

    HLA-A and -B antigens were determined in a group of 76 Greek asthmatic patients: 35 children (1.5-15 years) and 41 adults (18-73 years). The results were compared to those of 400 healthy unrelated controls from the same population. The standard NIH lymphocytotoxicity test was applied. When all 76 patients were compared to the controls, a statistically significant lower frequency of HLA-B5 and -B35 antigens was noted. When adults were analysed alone, an increased frequency of HLA-B8 was found. On the other hand, in the asthmatic children sub-group, the HLA-A10 antigen was significantly higher and the HLA-B5 was significantly lower than in the controls. These data imply that different HLA antigens may be involved in the pathogenesis of several clinical forms of asthma and that, in order to study the role of immunogenetic factor(s) in the pathogenesis of this disease, more adequate grouping criteria are needed.

  18. [Presence of Australia antigen in blood donors].

    Science.gov (United States)

    Gota, F

    1980-01-01

    The differential diagnosis of type A and B viral hepatitis is discussed and guidelines for the prevention of post-transfusional hospital hepatitis are proposed. Methods for the immunological demonstration of HBs antigen are illustrated, together with the respective positivity percentages in blood donors.

  19. Rational antigen modification as a strategy to upregulate or downregulate antigen recognition.

    Science.gov (United States)

    Abrams, S I; Schlom, J

    2000-02-01

    Recent and rapid advances in our understanding of the cellular and molecular mechanisms of antigen recognition by CD8(+) and CD4(+) T lymphocytes have led to the birth of possibilities for site-directed, rational modification of cognate antigenic determinants. This immunologic concept has vast biomedical implications for regulation of host immunity against the pathogenesis of diverse disease processes. The upregulation of antigen-specific T-cell responses by 'agonistic' peptides would be most desirable in response to invasive pathogenic challenges, such as infectious and neoplastic disease, while the downregulation of antigen-specific T-cell responses by 'antagonistic' peptides would be most efficacious during inappropriate pathologic consequences, such as autoimmunity. The capacity to experimentally manipulate intrinsic properties of cognate peptide ligands to appropriately alter the nature, course and potency of cellular immune interactions has important potential in both preventive and therapeutic clinical paradigms.

  20. Synergistic effects of ethanol and isopentenyl pyrophosphate on expansion of γδ T cells in synovial fluid from patients with arthritis.

    Directory of Open Access Journals (Sweden)

    Agneta J Laurent

    Full Text Available Low to moderate ethanol consumption has been associated with protective effects in autoimmune diseases such as rheumatoid arthritis, RA. An expansion of γδ T cells induced by isopentenyl pyrophosphate, IPP, likewise seems to have a protective role in arthritis. The aim of this project was to test the hypothesis that low doses of ethanol can enhance IPP-induced expansion of synovial fluid γδ T cells from patients with arthritis and may thereby potentially account for the beneficial effects of ethanol on symptoms of the arthritic process. Thus, mononuclear cells from synovial fluid (SF from 15 patients with arthritis and from peripheral blood (PB from 15 healthy donors were stimulated with low concentrations of ethanol and IPP for 7 days in vitro. IPP in combination with ethanol 0.015%, 2.5 mM, equivalent to the decrease per hour in blood ethanol concentration due to metabolism, gave a significantly higher fractional expansion of SF γδ T cells compared with IPP alone after 7 days (ratio 10.1+/-4.0, p<0.0008, n = 12 in patients with arthritis. Similar results were obtained for PB γδ T cells from healthy controls (ratio 2.0+/-0.4, p<0.011, n = 15. The augmented expansion of γδ T cells in SF is explained by a higher proliferation (p = 0.0034, n = 11 and an increased survival (p<0.005, n = 11 in SF cultures stimulated with IPP plus ethanol compared to IPP alone. The synergistic effects of IPP and ethanol indicate a possible allosteric effect of ethanol. Similar effects could be seen when stimulating PB with ethanol in presence of risedronate, which has the ability to increase endogenous levels of IPP. We conclude that expansion of γδ T cells by combinatorial drug effects, possibly in fixed-dose combination, FDC, of ethanol in the presence of IPP might give a protective role in diseases such as arthritis.

  1. Induction of furano-terpene production and formation of the enzyme system from mevalonate to isopentenyl pyrophosphate in sweet potato root tissue injured by Ceratocystis fimbriata and by toxic chemicals

    Energy Technology Data Exchange (ETDEWEB)

    Oba, K.; Tatematsu, H.; Yamashita, K.; Uritani, I.

    1976-07-01

    When sweet potato (Ipomoea batatas) root tissue was infected by Ceratocystis fimbriata, activity of the enzyme system from mevalonate to isopentenyl pyrophosphate, especially of pyrophosphomevalonate decarboxylase (EC 4.1.1.33), was increased in the noninfected tissue adjacent to the infected region, preceding the furano-terpene production in the infected region. Cutting and incubation of sweet potato slices did not produce furano-terpenes, and only slightly increased the activity of the enzyme system from mevalonate to isopentenyl pyrophosphate. The enzymic activity in diseased tissue was localized in the soluble fraction, and was higher in the tissue from the surface to a depth of about 5 mm with gradual decrease toward the inner part. Mercuric chloride (0.1%, w/v) and sodium dodecyl sulfate (1.0%, w/v) were utilized as model inducers of furano-terpenes and pyrophosphomevalonate decarboxylase. The mercuric chloride- or sodium dodecyl sulfate-induced response was inhibited by administration of cycloheximide to the discs together with the inducer immediately after disc preparation. When cycloheximide or blasticidin S was applied together with the inducer, to the discs 9 hours or more after disc preparation, the induction was not inhibited but rather stimulated.

  2. Comparison of E and NS1 antigens capture ELISA to detect dengue viral antigens from mosquitoes

    Directory of Open Access Journals (Sweden)

    Day-Yu Chao

    2015-01-01

    Interpretation & conclusion: With the future potential of antigen capture ELISA to be used in the resource deprived regions, the study showed that E-ELISA has similar sensitivity and antigen stability as NS1 Ag kit to complement the current established virological surveillance in human. The improvement of the sensitivity in detecting DENV-3/4 will be needed to incorporate this method into routine mosquito surveillance system.

  3. A Survey of ABO, Rhesus (D) Antigen and Haemoglobin Genes ...

    African Journals Online (AJOL)

    olayemitoyin

    This longitudinal study involved the determination of ABO and Rh(D) antigens in 3241 and ... Keywords: ABO antigen, Rhesus D, Blood group, Haemoglobin genotype, Blood substitutes ... composition, the variations in amino acid composition.

  4. Cysteine proteases as potential antigens in antiparasitic DNA vaccines

    DEFF Research Database (Denmark)

    Jørgensen, Louise von Gersdorff; Buchmann, Kurt

    2011-01-01

    En litteraturgennemgang af muligheder for at bruge cystein proteaser som antigener i antiparasitære vacciner.......En litteraturgennemgang af muligheder for at bruge cystein proteaser som antigener i antiparasitære vacciner....

  5. Dengue viruses cluster antigenically but not as discrete serotypes

    NARCIS (Netherlands)

    L. Katzelnick (Leah); J.M. Fonville (Judith); G.D. Gromowski (Gregory D.); J.B. Arriaga (Jose Bustos); A. Green (Angela); S.L. James (Sarah ); L. Lau (Louis); M. Montoya (Magelda); C. Wang (Chunling); L.A. Van Blargan (Laura A.); C.A. Russell (Colin); H.M. Thu (Hlaing Myat); T.C. Pierson (Theodore C.); P. Buchy (Philippe); J.G. Aaskov (John G.); J.L. Muñoz-Jordán (Jorge L.); N. Vasilakis (Nikos); R.V. Gibbons (Robert V.); R.B. Tesh (Robert B.); A.D.M.E. Osterhaus (Albert); R.A.M. Fouchier (Ron); A. Durbin (Anna); C.P. Simmons (Cameron P.); E.C. Holmes (Edward C.); E. Harris (Eva); S.S. Whitehead (Stephen S.); D.J. Smith (Derek James)

    2015-01-01

    textabstractThe four genetically divergent dengue virus (DENV) types are traditionally classified as serotypes. Antigenic and genetic differences among the DENV types influence disease outcome, vaccine-induced protection, epidemic magnitude, and viral evolution.We scharacterized antigenic diversity

  6. Comparison of Schistosoma mansoni soluble cercarial antigens and soluble egg antigens for serodiagnosing schistosome infections.

    Directory of Open Access Journals (Sweden)

    Huw Smith

    Full Text Available A Schistosoma mansoni cercarial antigen preparation (cercarial transformation fluid--SmCTF was evaluated for detection of anti-schistosome antibodies in human sera in 4 collaborating laboratories. The performance of SmCTF was compared with that of S. mansoni egg antigens (SmSEA in an indirect enzyme-immunoassay (ELISA antigen assay, the latter being used routinely in 3 of the 4 participating laboratories to diagnose S. mansoni and S. haematobium infections. In the fourth laboratory the performance of SmCTF was compared with that of S. japonicum egg antigens (SjSEA in ELISA for detection of anti-S. japonicum antibodies. In all 4 laboratories the results given by SmCTF in ELISA were very similar to those given by the antigen preparation routinely used in the respective laboratory to detect anti-schistosome antibodies in human infection sera. In so far as the ELISA results from SmCTF are thus so little different from those given by schistosome egg antigens and also cheaper to produce, the former is a potentially useful new diagnostic aid for schistosomiasis.

  7. Antigenic evaluation of a recombinant baculovirus-expressed Sarcocystis neurona SAG1 antigen.

    Science.gov (United States)

    Gupta, G D; Lakritz, J; Saville, W J; Livingston, R S; Dubey, J P; Middleton, J R; Marsh, A E

    2004-10-01

    Sarcocystis neurona is the primary parasite associated with equine protozoal myeloencephalitis (EPM). This is a commonly diagnosed neurological disorder in the Americas that infects the central nervous system of horses. Current serologic assays utilize culture-derived parasites as antigen. This method requires large numbers of parasites to be grown in culture, which is labor intensive and time consuming. Also, a culture-derived whole-parasite preparation contains conserved antigens that could cross-react with antibodies against other Sarcocystis species and members of Sarcocystidae such as Neospora spp., Hammondia spp., and Toxoplasma gondii. Therefore, there is a need to develop an improved method for the detection of S. neurona-specific antibodies. The sera of infected horses react strongly to surface antigen 1 (SnSAG1), an approximately 29-kDa protein, in immunoblot analysis, suggesting that it is an immunodominant antigen. The SnSAG1 gene of S. neurona was cloned, and recombinant S. neurona SAG1 protein (rSnSAG1-Bac) was expressed with the use of a baculovirus system. By immunoblot analysis, the rSnSAG1-Bac antigen detected antibodies to S. neurona from naturally infected and experimentally inoculated equids, cats, rabbit, mice, and skunk. This is the first report of a baculovirus-expressed recombinant S. neurona antigen being used to detect anti-S. neurona antibodies in a variety of host species.

  8. Mapping antigenic motifs in the trypomastigote small surface antigen from Trypanosoma cruzi.

    Science.gov (United States)

    Balouz, Virginia; Cámara, María de Los Milagros; Cánepa, Gaspar E; Carmona, Santiago J; Volcovich, Romina; Gonzalez, Nicolás; Altcheh, Jaime; Agüero, Fernán; Buscaglia, Carlos A

    2015-03-01

    The trypomastigote small surface antigen (TSSA) is a mucin-like molecule from Trypanosoma cruzi, the etiological agent of Chagas disease, which displays amino acid polymorphisms in parasite isolates. TSSA expression is restricted to the surface of infective cell-derived trypomastigotes, where it functions as an adhesin and engages surface receptors on the host cell as a prerequisite for parasite internalization. Previous results have established TSSA-CL, the isoform encoded by the CL Brener clone, as an appealing candidate for use in serology-based diagnostics for Chagas disease. Here, we used a combination of peptide- and recombinant protein-based tools to map the antigenic structure of TSSA-CL at maximal resolution. Our results indicate the presence of different partially overlapping B-cell epitopes clustering in the central portion of TSSA-CL, which contains most of the polymorphisms found in parasite isolates. Based on these results, we assessed the serodiagnostic performance of a 21-amino-acid-long peptide that spans TSSA-CL major antigenic determinants, which was similar to the performance of the previously validated glutathione S-transferase (GST)-TSSA-CL fusion molecule. Furthermore, the tools developed for the antigenic characterization of the TSSA antigen were also used to explore other potential diagnostic applications of the anti-TSSA humoral response in Chagasic patients. Overall, our present results provide additional insights into the antigenic structure of TSSA-CL and support this molecule as an excellent target for molecular intervention in Chagas disease.

  9. Antigenic community between Schistosoma mansoni and Biomphalaria glabrata: on the search of candidate antigens for vaccines

    Directory of Open Access Journals (Sweden)

    N Chacón

    2002-10-01

    Full Text Available We have previously confirmed the presence of common antigens between Schistosoma mansoni and its vector, Biomphalaria glabrata. Cross-reactive antigens may be important as possible candidates for vaccine and diagnosis of schistosomiasis. Sera from outbred mice immunized with a soluble Biomphalaria glabrata antigen (SBgA of non-infected B. glabrata snails recognized molecules of SBgA itself and S. mansoni AWA by Western blot. Recognition of several molecules of the SBgA were inhibited by pre-incubation with AWA (16, 30, 36, 60 and 155 kDa. The only specific molecule of AWA, inhibited by SBgA, was a 120 kDa protein. In order to determine which epitopes of SBgA were glycoproteins, the antigen was treated with sodium metaperiodate and compared with non-treated antigen. Molecules of 140, 60 and 24 kDa in the SBgA appear to be glycoproteins. Possible protective effects of the SBgA were evaluated immunizing outbred mice in two different experiments using Freund's Adjuvant. In the first one (12 mice/group, we obtained a significant level of protection (46% in the total worm load, with a high variability in worm recovery. In the second experiment (22 mice/group, no significant protection was observed, neither in worm load nor in egg production per female. Our results suggest that SBgA constitutes a rich source of candidate antigens for diagnosis and prophylactic studies.

  10. Sharing the burden: antigen transport and firebreaks in immune responses

    OpenAIRE

    Handel, Andreas; Yates, Andrew; Pilyugin, Sergei S.; Antia, Rustom

    2008-01-01

    Communication between cells is crucial for immune responses. An important means of communication during viral infections is the presentation of viral antigen on the surface of an infected cell. Recently, it has been shown that antigen can be shared between infected and uninfected cells through gap junctions, connexin-based channels, that allow the transport of small molecules. The uninfected cell receiving antigen can present it on its surface. Cells presenting viral antigen are detected and ...

  11. Synthetic antigens reveal dynamics of BCR endocytosis during inhibitory signaling.

    Science.gov (United States)

    Courtney, Adam H; Bennett, Nitasha R; Zwick, Daniel B; Hudon, Jonathan; Kiessling, Laura L

    2014-01-17

    B cells detect foreign antigens through their B cell antigen receptor (BCR). The BCR, when engaged by antigen, initiates a signaling cascade. Concurrent with signaling is endocytosis of the BCR complex, which acts to downregulate signaling and facilitate uptake of antigen for processing and display on the cell surface. The relationship between signaling and BCR endocytosis is poorly defined. Here, we explore the interplay between BCR endocytosis and antigens that either promote or inhibit B cell activation. Specifically, synthetic antigens were generated that engage the BCR alone or both the BCR and the inhibitory co-receptor CD22. The lectin CD22, a member of the Siglec family, binds sialic acid-containing glycoconjugates found on host tissues, inhibiting BCR signaling to prevent erroneous B cell activation. At low concentrations, antigens that can cocluster the BCR and CD22 promote rapid BCR endocytosis; whereas, slower endocytosis occurs with antigens that bind only the BCR. At higher antigen concentrations, rapid BCR endocytosis occurs upon treatment with either stimulatory or inhibitory antigens. Endocytosis of the BCR, in response to synthetic antigens, results in its entry into early endocytic compartments. Although the CD22-binding antigens fail to activate key regulators of antigen presentation (e.g., Syk), they also promote BCR endocytosis, indicating that inhibitory antigens can be internalized. Together, our observations support a functional role for BCR endocytosis in downregulating BCR signaling. The reduction of cell surface BCR levels in the absence of B cell activation should raise the threshold for BCR subsequent activation. The ability of the activating synthetic antigens to trigger both signaling and entry of the BCR into early endosomes suggests strategies for targeted antigen delivery.

  12. Cancer-germline antigen vaccines and epigenetic enhancers

    DEFF Research Database (Denmark)

    Gjerstorff, Morten Frier; Burns, Jorge; Ditzel, Henrik Jorn

    2010-01-01

    can be achieved using epigenetic modifiers. AREAS COVERED IN THIS REVIEW: We provide an overview of the potential of CG antigens as targets for cancer immunotherapy, including advantages and disadvantages. We also discuss the current state of development of CG antigen vaccines, and the potential...... antigen vaccines may be a useful approach for treating cancer....

  13. 21 CFR 866.3402 - Plasmodium species antigen detection assays.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Plasmodium species antigen detection assays. 866... Plasmodium species antigen detection assays. (a) Identification. A Plasmodium species antigen detection assay... malaria caused by the four malaria species capable of infecting humans: Plasmodium falciparum, Plasmodium...

  14. Immunity to intracellular Salmonella depends on surface-associated antigens.

    Directory of Open Access Journals (Sweden)

    Somedutta Barat

    Full Text Available Invasive Salmonella infection is an important health problem that is worsening because of rising antimicrobial resistance and changing Salmonella serovar spectrum. Novel vaccines with broad serovar coverage are needed, but suitable protective antigens remain largely unknown. Here, we tested 37 broadly conserved Salmonella antigens in a mouse typhoid fever model, and identified antigen candidates that conferred partial protection against lethal disease. Antigen properties such as high in vivo abundance or immunodominance in convalescent individuals were not required for protectivity, but all promising antigen candidates were associated with the Salmonella surface. Surprisingly, this was not due to superior immunogenicity of surface antigens compared to internal antigens as had been suggested by previous studies and novel findings for CD4 T cell responses to model antigens. Confocal microscopy of infected tissues revealed that many live Salmonella resided alone in infected host macrophages with no damaged Salmonella releasing internal antigens in their vicinity. In the absence of accessible internal antigens, detection of these infected cells might require CD4 T cell recognition of Salmonella surface-associated antigens that could be processed and presented even from intact Salmonella. In conclusion, our findings might pave the way for development of an efficacious Salmonella vaccine with broad serovar coverage, and suggest a similar crucial role of surface antigens for immunity to both extracellular and intracellular pathogens.

  15. Antigen-specific active immunotherapy for ovarian cancer

    NARCIS (Netherlands)

    Leffers, N.; Daemen, T.; Helfrich, W.; Boezen, H. M.; Cohlen, B. J.; Melief, Cornelis; Nijman, H. W.

    2010-01-01

    BACKGROUND: Despite advances in chemotherapy, prognosis of ovarian cancer remains poor. Antigen-specific active immunotherapy aims to induce a tumour-antigen-specific anti-tumour immune responses as an alternative treatment for ovarian cancer. OBJECTIVES: To assess feasibility of antigen-specific ac

  16. CA 19-9 (Cancer Antigen 19-9)

    Science.gov (United States)

    ... called Lewis antigen that is similar to the ABO antigens that are used in blood typing for transfusions. About 5% to 7% of people are Lewis antigen negative (about 30% in people of African ancestry) and do not produce CA 19-9. The CA 19-9 test is not useful for monitoring people who are ...

  17. 21 CFR 660.40 - Hepatitis B Surface Antigen.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 7 2010-04-01 2010-04-01 false Hepatitis B Surface Antigen. 660.40 Section 660.40...) BIOLOGICS ADDITIONAL STANDARDS FOR DIAGNOSTIC SUBSTANCES FOR LABORATORY TESTS Hepatitis B Surface Antigen § 660.40 Hepatitis B Surface Antigen. (a) Proper name and definition. The proper name of this...

  18. Recovery of antigenically reactive HIV-2 cores.

    Science.gov (United States)

    Chrystie, I L; Almeida, J D

    1989-03-01

    Negative staining studies of human immunodeficiency virus (HIV) have been hampered by the fragile nature of the particles. Although detergent treatment is capable of releasing cores from HIV-2 particles, these are unstable and do not retain morphological integrity. Addition of glutaraldehyde will stabilise these structures but, if used at too high a concentration, will destroy their antigenicity. This study shows that if both detergent and glutaraldehyde are used in correct proportions, antigenically reactive cores can be recovered from HIV-2 cell cultures. More specifically we show that a mixture of 0.1% Nonidet P40 and 0.1% glutaraldehyde produces preparations of HIV-2 cores that are suitable for immune electron microscopy. These cores reacted positively, that is, formed immune complexes, with both human HIV-2 antisera and a mouse monoclonal antibody that, although directed against p24 (HIV-1), reacts also with p25 (HIV-2).

  19. Mitochondrial antigens, molecular mimicry and autoimmune disease.

    Science.gov (United States)

    Baum, H

    1995-05-24

    The immune system is normally tolerant to mitochondrial self-antigens, but responsive against bacteria. Low-titre anti-mitochondrial antibodies (AMA) might be involved in this discrimination. Tolerance is broken in diseases characterised by high titre AMA. Some of these AMA, against cardiolipin, cross-react with DNA. The best studied AMA are those characterising primary biliary cirrhosis (PBC). These are directed against E2 subunits of the oxo-acid dehydrogenase complexes, and also against subunits E1 alpha, E1 beta and X of the pyruvate dehydrogenase complex. AMA of PBC patients also react with bacterial E2s. Reactivities are primarily peptide-specific but with cross-reactivity between mitochondrial and microbial antigens and between E2s of respective complexes. Immunodominant epitopes, for anti E2 AMA, include the conserved sequence flanking the site of lipoyl attachment. It is proposed that the initial stimulus for antibody production is chronic urinary tract infection. AMA themselves are not pathogenic, but CD4+ T-cells would be primed, recognising the lipoyl domain epitope in association with class II HLA. Inappropriate expression of class II antigens on bile duct epithelia, (as found in PBC), might lead to presentation of a particular fragment of HLA-DR alpha, known to be a major MHC presented self-peptide in the mouse. That sequence strongly mimics the lipoyl domain and might be recognised by primed T-cells, initiating the autoimmune cascade. In the mouse, a peptide of ND1 of Complex I is presented in association with class I MHC. Cells exhibiting somatic mutation of such a peptide might thus be subject to attack by CD8+ T-cells. If such peptides were presented by class II HLA, autoimmune diseases might arise, related to mimicry between such peptides and microbial sequences and/or self-antigens. These considerations might apply in Leber's disease and in age-related pathology.

  20. Tumor Immunity by Hydrophobic Bearing Antigens

    Science.gov (United States)

    2004-07-01

    protooncogene; TAL, tumor-associated lymphocyte; Perf, perforn, MRT, mean fluorescence intensity; IFN-g= Interferon gamma , FS= Forward scatter; Key words...Badovinac, V. P., T vinnereim, A. R., and Harty, J. T, Regulation of antigen-specific CD8+ Tcell homeostasis by perforin and interferon - gamma . Science...Cancer Res 2003; 63: 2535-45, 17. Zanussi, S., Vaceher, E., Caffau, C., et al. Interferon - gamma secretion and perforinexpression are impaired in CD8+ T

  1. Study of serum Helicobacter pylori soluble antigen

    Institute of Scientific and Technical Information of China (English)

    吴勤动; 朱永良

    2002-01-01

    Objective: to explore a new serological method for detecting Helicobac ter pylori ( H. pylori ) infection. Methods: Serum soluble antigen of H. p ylor i was detected by using avidin-biotin ELISA technique to evaluate the status of H. pylori infection and for comparison with rapid urease test ( RUT ), histo logi c examination and serology. Results: The sensitivity, specificity, positive pred ictive value and negative predictive value were 77.46%, 91.07%, 91.67% a nd 76.12 %, respectively. The prevalence rate of serum H. pylori soluble antigen in 138 patients undergoing endoscopy was similar to the rate obtained by 14 C-UBT met hods ( P>0.05 ). Conclusions: The detection of serum H. pylori solub le antigen( HpSAg) could be used as a new serological method which is accurate, and convenie nt, not affected by the memorizing reaction of serum antibody; is more sensitive , m ore specific and suitable for clinical diagnosis, and evaluation of eradication and for follow-up of H. pylori as well as for detection in children and pre gnant women.

  2. Study of serum Helicobacter pylori soluble antigen

    Institute of Scientific and Technical Information of China (English)

    吴勤动; 朱永良

    2002-01-01

    Objective:to explore a new serological method for detecting Helicobacter pylori(H.pylori) infection.Methods:Serum soluble antigen of H.pylori was detected by using avidin-biotin ELISA technique to evaluate the status of H.pylori infection and for comparison with rapid urease test(RUT).histologic examination and serology,Results:The sensitivity,specificity,positive predictive value and negative predictive value were 77.46% ,91.07%,91.67% and 76.12%,respectively.The prevalence rate of werum H. pylori soluble antigen in 138 patients undergong endoscopy was similar to the rate obtained by 14 C-UBT methods(P>0.05).Conclusions:The detection of serum H.pylori soluble antigen(HpSAg) could be used as a new serological method which is accurate,and convenient,not affected by the memorizing raction of serum antibody;is more sensitive,more specific and suitable for dinical diagriosis,and evaluation of eradication and for follow-up of H.pylori as well as for detection in children and pregnant women.

  3. Characterization of the human Goodpasture antigen.

    Science.gov (United States)

    Wieslander, J; Kataja, M; Hudson, B G

    1987-01-01

    The glomerular basement membrane antigen involved in Goodpasture syndrome was purified from human kidneys. The antigen was solubilized by collagenase digestion and purified by ion exchange chromatography, gel filtration and reversed phase HPLC. The monomer proteins (M1, M2*, and M3) were immunochemically compared with the corresponding bovine monomers and appeared to be identical. The Goodpasture reactivity was localized to the same monomer (M2*) as in bovine material. It could also be shown that eight out of nine patients with Goodpasture syndrome had circulating antibodies reacting with a crude collagenase digest of human glomerular basement membrane that could be inhibited by the active monomer peptide. The ninth patient had, besides antibodies to this peptide, antibodies to the 7S domain of type IV collagen. Further immunochemical studies indicate that all patients sera recognize the same site(s) on the monomer protein. Thus the major antigenic determinant(s) of Goodpasture syndrome resides in monomer M2* which is a constituent of the globular domain of collagen IV. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 PMID:3652534

  4. Limited antigenic variation in the Trypanosoma cruzi candidate vaccine antigen TSA-1.

    Science.gov (United States)

    Knight, J M; Zingales, B; Bottazzi, M E; Hotez, P; Zhan, B

    2014-12-01

    Chagas disease (American trypanosomiasis caused by Trypanosoma cruzi) is one of the most important neglected tropical diseases in the Western Hemisphere. The toxicities and limited efficacies of current antitrypanosomal drugs have prompted a search for alternative technologies such as a therapeutic vaccine comprised of T. cruzi antigens, including a recombinant antigen encoding the N-terminal 65 kDa portion of Trypomastigote surface antigen-1 (TSA-1). With at least six known genetically distinct T. cruzi lineages, variability between the different lineages poses a unique challenge for the development of broadly effective therapeutic vaccine. The variability across the major lineages in the current vaccine candidate antigen TSA-1 has not previously been addressed. To assess the variation in TSA-1, we cloned and sequenced TSA-1 from several different T. cruzi strains representing three of the most clinically relevant lineages. Analysis of the different alleles showed limited variation in TSA-1 across the different strains and fit with the current theory for the evolution of the different lineages. Additionally, minimal variation in known antigenic epitopes for the HLA-A 02 allele suggests that interlineage variation in TSA-1 would not impair the range and efficacy of a vaccine containing TSA-1.

  5. Expression, purification and antigenicity of Neospora caninum-antigens using silkworm larvae targeting for subunit vaccines.

    Science.gov (United States)

    Otsuki, Takahiro; Dong, Jinhua; Kato, Tatsuya; Park, Enoch Y

    2013-02-18

    Infection of Neospora caninum causes abortion in cattle, which has a serious worldwide impact on the economic performance of the dairy and beef industries. Now, inexpensive and efficacious vaccines are required to protect cattle from neosporosis in livestock industry. In this study, N. caninum surface antigen 1 (SAG1) and SAG1-related sequence 2 (SRS2) were expressed in hemolymph of silkworm larvae as a soluble form. Expressed SAG1 and SRS2 clearly showed antigenicity against N. caninum-positive sera of cow. SAG1 and SRS2 were purified to near homogeneity from hemolymph of silkworm larvae using anti-FLAG M2 antibody agarose: approximately 1.7 mg of SAG1 from 10 silkworm larvae and 370 μg of SRS2 from 17 silkworm larvae. Mice that were injected by antigens induced antibodies against SAG1 and SRS2. This study indicates that it is possible that this silkworm expression system leads to a large-scale production of N. caninum-antigens with biological function and low production cost. Bombyx mori nucleopolyhedrovirus (BmNPV) bacmid expression system paves the way to produce largely and rapidly these recombinant antigens for its application to subunit vaccines against neosporosis in cattle.

  6. Conformational Dynamics and Antigenicity in the Disordered Malaria Antigen Merozoite Surface Protein 2

    Science.gov (United States)

    Andrew, Dean; Krishnarjuna, Bankala; Nováček, Jiří; Žídek, Lukáš; Sklenář, Vladimír; Richards, Jack S.; Beeson, James G.; Anders, Robin F.; Norton, Raymond S.

    2015-01-01

    Merozoite surface protein 2 (MSP2) of Plasmodium falciparum is an abundant, intrinsically disordered protein that is GPI-anchored to the surface of the invasive blood stage of the malaria parasite. Recombinant MSP2 has been trialled as a component of a malaria vaccine, and is one of several disordered proteins that are candidates for inclusion in vaccines for malaria and other diseases. Nonetheless, little is known about the implications of protein disorder for the development of an effective antibody response. We have therefore undertaken a detailed analysis of the conformational dynamics of the two allelic forms of MSP2 (3D7 and FC27) using NMR spectroscopy. Chemical shifts and NMR relaxation data indicate that conformational and dynamic properties of the N- and C-terminal conserved regions in the two forms of MSP2 are essentially identical, but significant variation exists between and within the central variable regions. We observe a strong relationship between the conformational dynamics and the antigenicity of MSP2, as assessed with antisera to recombinant MSP2. Regions of increased conformational order in MSP2, including those in the conserved regions, are more strongly antigenic, while the most flexible regions are minimally antigenic. This suggests that modifications that increase conformational order may offer a means to tune the antigenicity of MSP2 and other disordered antigens, with implications for vaccine design. PMID:25742002

  7. Conformational dynamics and antigenicity in the disordered malaria antigen merozoite surface protein 2.

    Directory of Open Access Journals (Sweden)

    Christopher A MacRaild

    Full Text Available Merozoite surface protein 2 (MSP2 of Plasmodium falciparum is an abundant, intrinsically disordered protein that is GPI-anchored to the surface of the invasive blood stage of the malaria parasite. Recombinant MSP2 has been trialled as a component of a malaria vaccine, and is one of several disordered proteins that are candidates for inclusion in vaccines for malaria and other diseases. Nonetheless, little is known about the implications of protein disorder for the development of an effective antibody response. We have therefore undertaken a detailed analysis of the conformational dynamics of the two allelic forms of MSP2 (3D7 and FC27 using NMR spectroscopy. Chemical shifts and NMR relaxation data indicate that conformational and dynamic properties of the N- and C-terminal conserved regions in the two forms of MSP2 are essentially identical, but significant variation exists between and within the central variable regions. We observe a strong relationship between the conformational dynamics and the antigenicity of MSP2, as assessed with antisera to recombinant MSP2. Regions of increased conformational order in MSP2, including those in the conserved regions, are more strongly antigenic, while the most flexible regions are minimally antigenic. This suggests that modifications that increase conformational order may offer a means to tune the antigenicity of MSP2 and other disordered antigens, with implications for vaccine design.

  8. Inorganic pyrophosphate generation by transforming growth factor-beta-1 is mainly dependent on ANK induction by Ras/Raf-1/extracellular signal-regulated kinase pathways in chondrocytes.

    Science.gov (United States)

    Cailotto, Frederic; Bianchi, Arnaud; Sebillaud, Sylvie; Venkatesan, Narayanan; Moulin, David; Jouzeau, Jean-Yves; Netter, Patrick

    2007-01-01

    ANK is a multipass transmembrane protein transporter thought to play a role in the export of intracellular inorganic pyrophosphate and so to contribute to the pathophysiology of chondrocalcinosis. As transforming growth factor-beta-1 (TGF-beta1) was shown to favor calcium pyrophosphate dihydrate deposition, we investigated the contribution of ANK to the production of extracellular inorganic pyrophosphate (ePPi) by chondrocytes and the signaling pathways involved in the regulation of Ank expression by TGF-beta1. Chondrocytes were exposed to 10 ng/mL of TGF-beta1, and Ank expression was measured by quantitative polymerase chain reaction and Western blot. ePPi was quantified in cell supernatants. RNA silencing was used to define the respective roles of Ank and PC-1 in TGF-beta1-induced ePPi generation. Finally, selective kinase inhibitors and dominant-negative/overexpression plasmid strategies were used to explore the contribution of several signaling pathways to Ank induction by TGF-beta1. TGF-beta1 strongly increased Ank expression at the mRNA and protein levels, as well as ePPi production. Using small interfering RNA technology, we showed that Ank contributed approximately 60% and PC-1 nearly 20% to TGF-beta1-induced ePPi generation. Induction of Ank by TGF-beta1 required activation of the extracellular signal-regulated kinase (ERK) pathway but not of p38-mitogen-activated protein kinase or of protein kinase A. In line with the general protein kinase C (PKC) inhibitor calphostin C, Gö6976 (a Ca2+-dependent PKC inhibitor) diminished TGF-beta1-induced Ank expression by 60%, whereas a 10% inhibition was observed with rottlerin (a PKCdelta inhibitor). These data suggest a regulatory role for calcium in TGF-beta1-induced Ank expression. Finally, we demonstrated that the stimulatory effect of TGF-beta1 on Ank expression was inhibited by the suppression of the Ras/Raf-1 pathway, while being enhanced by their constitutive activation. Transient overexpression of Smad 7, an

  9. Modulation of antigenicity of mycelial antigens during developmental cycle of Karnal bunt (Tilletia indica) of wheat.

    Science.gov (United States)

    Rai, G; Kumar, A; Singh, A; Garg, G K

    2000-05-01

    Indirect enzyme linked immunosorbent assays (ELISA) were developed using polyclonal antibodies against soluble cytoplasmic (SCA) and insoluble cell wall antigens (ICWA) for monitoring modulation of mycelial antigens during growth cycle of T. indica. With SCA, continuous decrease in ELISA reactivity was observed in maturing fungus cultures, suggesting that SCA were expressed predominantly during early vegetative phase and their decreasing role was apparent as the fungus matures possibly towards sporogenous mycelium. In case of ICWA, the reaction profile showed an increase up to exponential phase of growth probably due to increase in the cell division and branching of mycelium. But later, ICWA antibody reactivity was decreased which may be due to conversion of mycelial phase to sporogenous phase, a quiescent stage of growth. Characterization of changes in antigenic configuration during developmental cycle of Tilletia indica by these antibodies could prove to be useful in identification of developmentally related and virulence marker(s).

  10. Genetic diversity and antigenicity variation of Babesia bovis merozoite surface antigen-1 (MSA-1) in Thailand.

    Science.gov (United States)

    Tattiyapong, Muncharee; Sivakumar, Thillaiampalam; Takemae, Hitoshi; Simking, Pacharathon; Jittapalapong, Sathaporn; Igarashi, Ikuo; Yokoyama, Naoaki

    2016-07-01

    Babesia bovis, an intraerythrocytic protozoan parasite, causes severe clinical disease in cattle worldwide. The genetic diversity of parasite antigens often results in different immune profiles in infected animals, hindering efforts to develop immune control methodologies against the B. bovis infection. In this study, we analyzed the genetic diversity of the merozoite surface antigen-1 (msa-1) gene using 162 B. bovis-positive blood DNA samples sourced from cattle populations reared in different geographical regions of Thailand. The identity scores shared among 93 msa-1 gene sequences isolated by PCR amplification were 43.5-100%, and the similarity values among the translated amino acid sequences were 42.8-100%. Of 23 total clades detected in our phylogenetic analysis, Thai msa-1 gene sequences occurred in 18 clades; seven among them were composed of sequences exclusively from Thailand. To investigate differential antigenicity of isolated MSA-1 proteins, we expressed and purified eight recombinant MSA-1 (rMSA-1) proteins, including an rMSA-1 from B. bovis Texas (T2Bo) strain and seven rMSA-1 proteins based on the Thai msa-1 sequences. When these antigens were analyzed in a western blot assay, anti-T2Bo cattle serum strongly reacted with the rMSA-1 from T2Bo, as well as with three other rMSA-1 proteins that shared 54.9-68.4% sequence similarity with T2Bo MSA-1. In contrast, no or weak reactivity was observed for the remaining rMSA-1 proteins, which shared low sequence similarity (35.0-39.7%) with T2Bo MSA-1. While demonstrating the high genetic diversity of the B. bovis msa-1 gene in Thailand, the present findings suggest that the genetic diversity results in antigenicity variations among the MSA-1 antigens of B. bovis in Thailand.

  11. New diagnostic antigens for early trichinellosis: the excretory-secretory antigens of Trichinella spiralis intestinal infective larvae.

    Science.gov (United States)

    Sun, Ge Ge; Liu, Ruo Dan; Wang, Zhong Quan; Jiang, Peng; Wang, Li; Liu, Xiao Lin; Liu, Chun Yin; Zhang, Xi; Cui, Jing

    2015-12-01

    The excretory-secretory (ES) antigens from Trichinella spiralis muscle larvae (ML) are the most commonly used diagnostic antigens for trichinellosis, but anti-Trichinella IgG antibodies cannot be detected until 2-3 weeks after infection; there is an obvious window period between Trichinella infection and antibody positivity. Intestinal infective larvae (IIL) are the first invasive stage during Trichinella infection, and their ES antigens are firstly exposed to the immune system and might be the early diagnostic markers of trichinellosis. The aim of this study was to evaluate the early diagnostic values of IIL ES antigens for trichinellosis. The IIL were collected from intestines of infected mice at 6 h postinfection (hpi), and IIL ES antigens were prepared by incubation for 18 h. Anti-Trichinella IgG antibodies in mice infected with 100 ML were detectable by ELISA with IIL ES antigens as soon as 10 days postinfection (dpi), but ELISA with ML ES antigens did not permit detection of infected mice before 12 dpi. When the sera of patients with trichinellosis at 19 dpi were assayed, the sensitivity (100 %) of ELISA with IIL ES antigens was evidently higher than 75 % of ELISA with ML ES antigens (P < 0.05) The specificity (96.86 %) of ELISA with IIL ES antigens was also higher than 89.31 % of ELISA with ML ES antigens (P < 0.05). The IIL ES antigens provided a new source of diagnostic antigens and could be considered as a potential early diagnostic antigen for trichinellosis.

  12. Overlapping antigenic repertoires of variant antigens expressed on the surface of erythrocytes infected by Plasmodium falciparum

    DEFF Research Database (Denmark)

    Giha, H A; Staalsoe, T; Dodoo, D;

    1999-01-01

    Antibodies against variable antigens expressed on the surface of Plasmodium falciparum-infected erythrocytes are believed to be important for protection against malaria. A target for these antibodies is the P. falciparum erythrocyte membrane protein 1, PfEMP1, which is encoded by around 50 var...... genes and undergoes clonal variation. Using agglutination and mixed agglutination tests and flow cytometry to analyse the recognition of variant antigens on parasitized erythrocytes by plasma antibodies from individuals living in Daraweesh in eastern Sudan, an area of seasonal and unstable malaria...

  13. Farnesyl pyrophosphate synthase enantiospecificity with a chiral risedronate analog, [6,7-dihydro-5H-cyclopenta[c]pyridin-7-yl(hydroxy)methylene]bis(phosphonic acid) (NE-10501): Synthetic, structural, and modeling studies

    Energy Technology Data Exchange (ETDEWEB)

    Deprele, Sylvine; Kashemirov, Boris A.; Hogan, James M.; Ebetino, Frank H.; Barnett, Bobby L.; Evdokimov, Artem; McKenna, Charles E. (USC); (UCIN); (PG)

    2008-08-19

    The complex formed from crystallization of human farnesyl pyrophosphate synthase (hFPPS) from a solution of racemic [6,7-dihydro-5H-cyclopenta[c]pyridin-7-yl(hydroxy)methylene]bis(phosphonic acid) (NE-10501, 8), a chiral analog of the anti-osteoporotic drug risedronate, contained the R enantiomer in the enzyme active site. This enantiospecificity was assessed by computer modeling of inhibitor-active site interactions using Autodock 3, which was also evaluated for predictive ability in calculations of the known configurations of risedronate, zoledronate, and minodronate complexed in the active site of hFPPS. In comparison with these structures, the 8 complex exhibited certain differences, including the presence of only one Mg{sup 2+}, which could contribute to its 100-fold higher IC{sub 50}. An improved synthesis of 8 is described, which decreases the number of steps from 12 to 8 and increases the overall yield by 17-fold.

  14. Effect of vitamin D/sub 3/, other drugs altering serum calcium or phosphorus concentrations, and desoxycorticosterone on the distribution of Tc-99m pyrophosphate between target and nontarget tissues. [Rats

    Energy Technology Data Exchange (ETDEWEB)

    Carr, E.A. Jr.; Carroll, M.; Montes, M.

    1981-06-01

    Radioactive imaging agents are chemically designed for selective distribution. Another approach to selectivity is to find stable compounds that favorably influence this distribution. Using a rat model of myocardial necrosis, the effects of various stable compounds on the ratio, uptake of Tc-99m pyrophosphate (PPi) by the target lesion/uptake by the principal nontarget, bone (L/B) were studied. Vitamin D/sub 3/s ability to increase L/B was mediated by the hypercalcemia and hyperphosphatemia that it caused. In contrast, pulse doses of desoxycorticosterone acetate (DOCA) at 7 and 6 h before killing increased uptake by lesion, with no change in serum (Ca) and minimal changes in serum (P), (Na), and (K). DOCA also increased the lesion-to-blood ratio. These results encourage further study of DOCA's effect and investigation of other stable drugs that may influence distribution of other imaging agents.

  15. Tissue polypeptide antigen activity in cerebrospinal fluid

    DEFF Research Database (Denmark)

    Bach, F; Söletormos, Georg; Dombernowsky, P

    1991-01-01

    in the CSF and neurological clinical function. TPpA concentrations decreased in parallel with the clinical response and increased prior to CNS disease progression. As a marker for CNS metastases, the level of TPpA in the CSF in breast cancer patients appears to be superior to the level of protein, lactate......Tissue polypeptide antigen (TPpA) in the cerebrospinal fluid (CSF) was measured in 59 consecutive breast cancer patients with suspected central nervous system (CNS) metastases. Subsequently, we determined that 13 patients had parenchymal brain metastases, 10 had leptomeningeal carcinomatosis...

  16. Biofunctionalizing nanofibers with carbohydrate blood group antigens.

    Science.gov (United States)

    Barr, Katie; Kannan, Bhuvaneswari; Korchagina, Elena; Popova, Inna; Ryzhov, Ivan; Henry, Stephen; Bovin, Nicolai

    2016-11-01

    A rapid and simple method of biofunctionalising nylon, cellulose acetate, and polyvinyl butyral electrospun nanofibers with blood group glycans was achieved by preparing function-spacer-lipid constructs and simply contacting them to fibers with a piezo inkjet printer. A series of water dispersible amphipathic glycan-spacer constructs were synthesized representing a range ABO and related blood group antigens. After immediate contact of the amphipathic glycan-spacer constructs with nanofiber surfaces they self-assembled and were detectable by enzyme immunoassays with high sensitivity and specificity.

  17. Studies on the Antigenic Relationship among Phleboviruses

    Science.gov (United States)

    1982-01-01

    was easily differentiated by this method. Rift Valley fever virus was shown to be antigenically related to Candiru, Frijoles , Karimabad and Punta... Frijoles VP-161A HS(3) _-90% plaque reduction were recorded as positive. Gabek Forest Sud An 754-61 RS(3) Gordil Dak An B 496d MAF(4) Icoaraci Be An...10 10 0 0 80 0 0 2,60 0 40 0 0 CHILIBRE ង ង ង ង ង ង ង ង ង ង 1,280 ង ង ង FRIJOLES 0 0 0 0 0 0 0 0 0 0 0 10,240 0 0 GABEK

  18. Protective antibody titres and antigenic competition in multivalent Dichelobacter nodosus fimbrial vaccines using characterised rDNA antigens.

    Science.gov (United States)

    Raadsma, H W; O'Meara, T J; Egerton, J R; Lehrbach, P R; Schwartzkoff, C L

    1994-03-01

    The relationship between K-agglutination antibody titres and protection against experimental challenge with Dichelobacter nodosus, the effect of increasing the number of D. nodosus fimbrial antigens, and the importance of the nature of additional antigens in multivalent vaccines on antibody response and protection against experimental challenge with D. nodosus were examined in Merino sheep. A total of 204 Merino sheep were allocated to one of 12 groups, and vaccinated with preparations containing a variable number of rDNA D. nodosus fimbrial antigens. The most complex vaccine contained ten fimbrial antigens from all major D. nodosus serogroups, while the least complex contained a single fimbrial antigen. In addition to D. nodosus fimbrial antigens, other bacterial rDNA fimbrial antigens (Moraxella bovis Da12d and Escherichia coli K99), and bovine serum albumin (BSA) were used in some vaccines. Antibody titres to fimbrial antigens and BSA were measured by agglutination and ELISA tests, respectively. Antibody titres were determined on five occasions (Weeks 0, 3, 6, 8, and 11 after primary vaccination). All sheep were exposed to an experimental challenge with virulent isolates of D. nodosus from either serogroup A or B, 8 weeks after primary vaccination. For D. nodosus K-agglutinating antibody titres, a strong negative correlation between antibody titre and footrot lesion score was observed. This relationship was influenced by the virulence of the challenge strain. Increasing the number of fimbrial antigens in experimental rDNA D. nodosus fimbrial vaccines resulted in a linear decrease in K-agglutinating antibody titres to individual D. nodosus serogroups. Similarly, a linear decrease in protection to challenge with homologous serogroups was observed as the number of D. nodosus fimbrial antigens represented in the vaccine increased. The reduction in antibody titres in multicomponent vaccines is thought to be due to antigenic competition. The level of competition

  19. Antigen-induced and non-antigen-induced histamine release from rat mast cells sensitized with mouse antiserum.

    Directory of Open Access Journals (Sweden)

    Kurose,Masao

    1981-10-01

    Full Text Available Marked IgE-mediated histamine release from rat mast cells sensitized in vitro with mouse antiserum occurs in the presence of added Ca++ and phosphatidylserine (PS, although a considerable degree of antigen-induced histamine release which may utilize intracellular or cell-bound calcium is also observed. The decay in the responsiveness to Ca++ of the sensitized cells stimulated by antigen in Ca++-free medium in the presence of PS is relatively slow, and maximum release is produced by Ca++ added 1 min after antigen. Histamine release also occurs when Ca++ is added after PS in the absence of antigen to the sensitized cells suspended in Ca++-free medium. Unlike the antigen-induced release, the intensity of this non-antigen-induced release varies depending on both mast-cell and antiserum pools. A heat-labile factor(s, which is different from antigen-specific IgE antibody and is also contained in normal mouse serum, is involved in this reaction. In the antigen-nondependent (PS + Ca++-induced release, no decay in the responsiveness to Ca++ is observed after PS addition. Both the antigen-induced and non-antigen-induced release are completed fairly rapidly and are dependent of temperature, pH and energy.

  20. Strategies to enhance immunogenicity of cDNA vaccine encoded antigens by modulation of antigen processing

    NARCIS (Netherlands)

    Platteel, Anouk C M; Marit de Groot, A; Andersen, Peter; Ovaa, Huib; Kloetzel, Peter M; Mishto, Michele; Sijts, Alice J A M

    2016-01-01

    Most vaccines are based on protective humoral responses while for intracellular pathogens CD8(+) T cells are regularly needed to provide protection. However, poor processing efficiency of antigens is often a limiting factor in CD8(+) T cell priming, hampering vaccine efficacy. The multistage cDNA va

  1. Mycobacterium leprae antigens involved in human immune responses. I. Identification of four antigens by monoclonal antibodies

    Energy Technology Data Exchange (ETDEWEB)

    Britton, W.J.; Hellqvist, L.; Basten, A.; Raison, R.L.

    1985-12-01

    Four distinct antigens were identified in soluble sonicates of Mycobacterium leprae by using a panel of 11 monoclonal antibodies. Cross-reactivity studies with other mycobacterial species were conducted by using ELISA and immunoblot assays, and demonstrated that determinants on two of the antigens were present in many mycobacteria, whereas the other two were limited in distribution. Competitive inhibition experiments with radiolabeled monoclonal antibodies showed cross-inhibition between antibodies identifying two of the four antigenicbands. These two bands, of M/sub tau/ 4.5 to 6 KD and 30 to 40 KD, were resistant to protease treatment after immunoblotting. In contrast the two other bands of 16 and 70 KD were protease-sensitive. Although all four bands reacted with some human lepromatous leprosy sera in immunoblots, the 4.5 to 6 KD and 30 to 40 KD bands were most prominent. Lepromatous leprosy sera also inhibited the binding of radiolabeled monoclonal antibodies to each of the four antigens, with the mean titer causing 50% inhibition being higher for antibodies reacting with the 4.5 to 6 KD and 30 to 40 KD bands. These findings indicated that all four antigens were involved in the human B cell response to M. leprae.

  2. Antigen presentation for priming T cells in central system.

    Science.gov (United States)

    Dasgupta, Shaoni; Dasgupta, Subhajit

    2017-01-01

    Generation of myelin antigen-specific T cells is a major event in neuroimmune responses that causes demyelination. The antigen-priming of T cells and its location is important in chronic and acute inflammation. In autoimmune multiple sclerosis, the effector T cells are considered to generate in periphery. However, the reasons for chronic relapsing-remitting events are obscure. Considering mechanisms, a feasible aim of research is to investigate the role of antigen-primed T cells in lupus cerebritis. Last thirty years of investigations emphasize the relevance of microglia and infiltrated dendritic cells/macrophages as antigen presenting cells in the central nervous system. The recent approach towards circulating B-lymphocytes is an important area in the context. Here, we analyze the existing findings on antigen presentation in the central nervous system. The aim is to visualize signaling events of myelin antigen presentation to T cells and lead to the strategy of future goals on immunotherapy research.

  3. Human Ia-like antigens in non-lymphoid organs.

    Science.gov (United States)

    Koyama, K; Fukunishi, T; Barcos, M; Tanigaki, N; Pressman, D

    1979-01-01

    Human Ia-like antigens in liver and kidney were shown by the immunofluorescence assay to be present mostly in the endothelial-mesenchymal cells of these organs. The parenchymal cells apparently contained no human Ia-like antigens. The antigens in liver and kidney were purified and shown to have the same subunit structure as human Ia-like antigens of cultured B-lymphoid cells. The human Ia-like antigens in non-lymphoid organs, not only in liver and kidney but also in testis, heart, muscle and brain, carried all the xenoantigenic characteristics of human Ia-like antigens expressed on lymphoid cells of B-cell lineage. Images Figure 1 PMID:389786

  4. Tissue distribution of histo-blood group antigens

    DEFF Research Database (Denmark)

    Ravn, V; Dabelsteen, Erik

    2000-01-01

    carrier carbohydrate chains. Histo-blood group antigens are found in most epithelial tissues. Meanwhile, several factors influence the type, the amount, and the histological distribution of histoblood group antigens, i.e. the ABO, Lewis, and saliva-secretor type of the individual, and the cell- and tissue......The introduction of immunohistochemical techniques and monoclonal antibodies to specific carbohydrate epitopes has made it possible to study in detail the tissue distribution of histo-blood group antigens and related carbohydrate structures. The present paper summarizes the available data...... concerning the histological distribution of histo-blood group antigens and their precursor structures in normal human tissues. Studies performed have concentrated on carbohydrate antigens related to the ABO, Lewis, and TTn blood group systems, i.e. histo-blood group antigens carried by type 1, 2, and 3 chain...

  5. Immunoregulation by Taenia crassiceps and Its Antigens

    Directory of Open Access Journals (Sweden)

    Alberto N. Peón

    2013-01-01

    Full Text Available Taenia crassiceps is a cestode parasite of rodents (in its larval stage and canids (in its adult stage that can also parasitize immunocompromised humans. We have studied the immune response elicited by this helminth and its antigens in mice and human cells, and have discovered that they have a strong capacity to induce chronic Th2-type responses that are primarily characterized by high levels of Th2 cytokines, low proliferative responses in lymphocytes, an immature and LPS-tolerogenic profile in dendritic cells, the recruitment of myeloid-derived suppressor cells and, specially, alternatively activated macrophages. We also have utilized the immunoregulatory capabilities of this helminth to successfully modulate autoimmune responses and the outcome of other infectious diseases. In the present paper, we review the work of others and ourselves with regard to the immune response induced by T. crassiceps and its antigens, and we compare the advances in our understanding of this parasitic infection model with the knowledge that has been obtained from other selected models.

  6. Glycoconjugates as target antigens in peripheral neuropathies

    Directory of Open Access Journals (Sweden)

    Ljubica Suturkova

    2014-12-01

    Full Text Available Identification and characterization of antigens present at the human peripheral nerve is a great challenge in the field of neuroimmunology. The latest investigations are focused on the understanding of the biology of glycoconjugates present at the peripheral nerve, and their immunological reactivity. Increased titers of antibodies that recognize carbohydrate determinants of glycoconjugates (glycolipids and glycoproteins are associated with distinct neuropathic syndromes. There is considerable cross-reactivity among anti-ganglioside antibodies, resulting from shared oligosaccharide epitopes, possibly explaining the overlap in syndromes observed in many affected patients. Sera from patients with neuropathies (GBS, chronic inflammatory demielynating polyneuropathy - CIDP, multifocal motor neuropathy - MMN, cross-react with glycoproteins isolated from human peripheral nerve and from Campylobacter jejuni O:19. The frequency of occurrence of antibodies against these glycoproteins is different, depending of the type of neuropathy. Identification of the cross-reactive glycoproteins and possible additional auto antigens could be useful in laboratory evaluation of peripheral neuropathies and help to develop a more effective therapeutic approach.

  7. Antigen epitope of Helicobacter pylorivacuolating cytotoxin A

    Institute of Scientific and Technical Information of China (English)

    Xiu-Li Liu; Shu-Qin Li; Chun-Jie Liu; Hao-Xia Tao; Zhao-Shan Zhang

    2004-01-01

    AIM: To construct and select antigen epitopes of vacuolating cytotoxin A (VacA) for nontoxic VacA vaccine against Helicobacter pylori (H pylori) infection.METHODS: Eleven VacA epitopes were predicted according to VacA antigenic bioinformatics. Three candidates of VacA epitope were constructed through different combined epitopes. The candidate was linked with E. coli heat-labile enterotoxin B (LTB) by a linker of 7 amino acids, and cloned into plasmid pQE-60 in which fusion LTB-VacA epitope was efficiently expressed. To test the antigencity of the candidate, 6 BALB/c mice were treated with the fusion LTB-VacA epitope through intraperitoneal injection. To explore the ability of inhibiting the toxicity of VacA, cantiserum against the candidate was used to counteract VacA that induced HeLa cells to produce cell vacuoles in vitro.RESULTS: Serum IgG against the candidate was induced in the BALB/c mice. In vitro, the three antisera against the candidate efficiently counteracted the toxicity of VacA, and decreased the number of cell vacuoles by 14.17%, 20.20%and 30.41% respectively.CONCLUSION: Two of the three candidates, LZ-VacA1and LZ-VacA2, can be used to further study the mechanism of vacuolating toxicity of VacA, and to construct nontoxic VacA vaccine against H pylori infection.

  8. Immune responses to chlamydial antigens in humans.

    Science.gov (United States)

    Hanna, L; Kerlan, R; Senyk, G; Stites, D P; Juster, R P; Jawetz, E

    1982-01-01

    Antibody titer, lymphocyte stimulation and leukocyte migration inhibition with chlamydial antigens were determined repeatedly over many months on human subjects. The volunteers were retrospectively placed into four groups on the basis of clinical, laboratory and epidemiologic criteria. Group A consisted of persons with proven or probable chlamydial infection, including an illness confirmed by chlamydial isolation or seroconversion, or a clinically compatible illness with positive serologic results. Group B were sexual partners or close contacts of group A individuals. Group C were laboratory workers with prolonged exposure to viable chlamydiae or their antigens. Group D included persons of comparable age as those in groups A and B, but lacking a history of symptomatic chlamydial infection or of contact with chlamydiae. Individual cases illustrated the rise of antibody and some cell mediated immunity reactions (CMI) with active chlamydial infection. By contrast, laboratory exposure resulted in elevation of CMI but not of antibody. Statistical analysis of the results in 46 volunteers tested repeatedly indicated a strong association of specific antibody with lymphocyte stimulation, but not with leukocyte migration inhibition. Regression analysis suggested that the type of exposure markedly influenced the relationship between antibody and lymphocyte stimulation. Measurement of immunotype-specific antibody titer by microimmunofluorescence (or an equally sensitive method) remains the best laboratory indicator of past chlamydial infection. Neither antibody nor CMI can, as yet, be definitely related to resistance to re-infection in humans.

  9. Detection of peste des petits ruminants virus antigen using immunofiltration and antigen-competition ELISA methods.

    Science.gov (United States)

    Raj, G Dhinakar; Rajanathan, T M C; Kumar, C Senthil; Ramathilagam, G; Hiremath, Geetha; Shaila, M S

    2008-06-22

    Peste des petits ruminants (PPR) is one of the most economically important diseases affecting sheep and goats in India. An immunofiltration-based test has been developed using either mono-specific serum/monoclonal antibodies (mAb) prepared against a recombinant truncated nucleocapsid protein of rinderpest virus (RPV) cross-reactive with PPR virus. This method consists of coating ocular swab eluate from suspected animals onto a nitrocellulose membrane housed in a plastic module, which is allowed to react with suitable dilutions of a mAb or a mono-specific polyclonal antibody. The antigen-antibody complex formed on the membrane is then detected by protein A-colloidal gold conjugate, which forms a pink colour. In the immunofiltration test, concordant results were obtained using either PPRV mAb or mono-specific serum. Another test, an antigen-competition ELISA which relies on the competition between plate-coated recombinant truncated 'N' protein of RPV and the PPRV 'N' protein present in ocular swab eluates (sample) for binding to the mono-specific antibody against N protein of RPV (in liquid phase) was developed. The cut-off value for this test was established using reverse transcription polymerase chain reaction (RT-PCR) positive and negative oculo-nasal swab samples. Linear correlation between percent inhibition (PI) values in antigen-competition ELISA and virus infectivity titres was 0.992. Comparison of the immunofiltration test with the antigen-competition ELISA yielded a sensitivity of 80% and specificity of 100%. These two tests can serve as a screening (immunofiltration) and confirmatory (antigen-competition ELISA) test, respectively, in the diagnosis of PPR in sheep or goats.

  10. СAPSULAR ANTIGEN OF YERSINIA PESTIS

    Directory of Open Access Journals (Sweden)

    L. A. Kadnikova

    2015-01-01

    Full Text Available Plague is a zoonosis caused by gram-negative bacteria Yersinia pestis, which, as a rule, is transmitted to humans from septicemic rodents by the bites of infected fleas. This microbe killed more people than all of the wars in the human history. Y. pestis circulation in the natural plague foci is ensured by the whole number of pathogenicity factors with differing functional orientation. This review is devoted to one of them, Y. pestis capsular antigen (F1 or Caf1. The history of its discovery and studying of its genetic control, biosynthesis, isolation and purification, and physicochemical properties are reviewed. Its roles in plague pathogenesis and its application as a main component of plague vaccines are also discussed. Y. pestis capsule under light microscopy is visually amorphous, while high-resolution electron microscopy displays the structure formed from separate fimbria-like cords up to 200 nm long, diverging from the bacterial surface in different directions. At 37°C Y. pestis produce 800–1000 times more capsular antigen than at 28°C. Genes coding for 17.6-kD Caf1 protein, which contains 170 amino acids, are located in caf1 operon of pFra plasmid. Analysis of caf1 operon nucleotide sequence testified its close phylogenetic relationship with the gene clusters coding for pilus adhesins that were secreted with the help of chaperone/usher systems in enterobacteria including six additional adhesins in Y. pestis. Y. pestis multiplication within macrophages is the obligatory stage of plague pathogenesis, and the plague pathogen virulence correlates not with resistance to phagocyte ingesting but with bacterial ability to survive and multiply within phagolysosomes of phagocytes due to neutralization of antibacterial functions of eukaryotic cells. The capsule formed out of the Caf1 aggregates protects Y. pestis from ingestion by naïve host’s phagocytes and prevents from initiation of the alternative pathway of the complement system

  11. Bayesian nonparametric clustering in phylogenetics: modeling antigenic evolution in influenza.

    Science.gov (United States)

    Cybis, Gabriela B; Sinsheimer, Janet S; Bedford, Trevor; Rambaut, Andrew; Lemey, Philippe; Suchard, Marc A

    2017-01-18

    Influenza is responsible for up to 500,000 deaths every year, and antigenic variability represents much of its epidemiological burden. To visualize antigenic differences across many viral strains, antigenic cartography methods use multidimensional scaling on binding assay data to map influenza antigenicity onto a low-dimensional space. Analysis of such assay data ideally leads to natural clustering of influenza strains of similar antigenicity that correlate with sequence evolution. To understand the dynamics of these antigenic groups, we present a framework that jointly models genetic and antigenic evolution by combining multidimensional scaling of binding assay data, Bayesian phylogenetic machinery and nonparametric clustering methods. We propose a phylogenetic Chinese restaurant process that extends the current process to incorporate the phylogenetic dependency structure between strains in the modeling of antigenic clusters. With this method, we are able to use the genetic information to better understand the evolution of antigenicity throughout epidemics, as shown in applications of this model to H1N1 influenza. Copyright © 2017 John Wiley & Sons, Ltd.

  12. Identification of protective antigens for vaccination against systemic salmonellosis

    Directory of Open Access Journals (Sweden)

    Dirk eBumann

    2014-08-01

    Full Text Available There is an urgent medical need for improved vaccines with broad serovar coverage and high efficacy against systemic salmonellosis. Subunit vaccines offer excellent safety profiles but require identification of protective antigens, which remains a challenging task. Here, I review crucial properties of Salmonella antigens that might help to narrow down the number of potential candidates from more than 4000 proteins encoded in Salmonella genomes, to a more manageable number of 50-200 most promising antigens. I also discuss complementary approaches for antigen identification and potential limitations of current pre-clinical vaccine testing.

  13. MHC structure and function – antigen presentation. Part 1

    Science.gov (United States)

    Goldberg, Anna Carla; Rizzo, Luiz Vicente

    2015-01-01

    The setting for the occurrence of an immune response is that of the need to cope with a vast array of different antigens from both pathogenic and non-pathogenic sources. When the first barriers against infection and innate defense fail, adaptive immune response enters the stage for recognition of the antigens by means of extremely variable molecules, namely immunoglobulins and T-cell receptors. The latter recognize the antigen exposed on cell surfaces, in the form of peptides presented by the HLA molecule. The first part of this review details the central role played by these molecules, establishing the close connection existing between their structure and their antigen presenting function. PMID:25807245

  14. Do FY antigens act as minor histocompatibility antigens in the graft-versus-host disease paradigm after human leukocyte antigen-identical sibling hematopoietic stem cell transplantation?

    Science.gov (United States)

    Sellami, Mohamed Hichem; Chaabane, Manel; Kaabi, Houda; Torjemane, Lamia; Ladeb, Saloua; Ben Othmane, Tarek; Hmida, Slama

    2012-03-01

    FY antigens are candidate minor histocompatibility antigens relevant to renal allograft rejection, but no data have been reported about their role in graft-versus-host disease (GVHD) incidence after human leukocyte antigen (HLA)-identical siblings hematopoietic stem cell transplantation (HSCT). The aim of this study was to examine the effect of donor/recipient disparity at FY antigens on the incidence of GVHD in Tunisian patients receiving an HLA-identical HSCT. This work enrolled 105 Tunisian pairs of recipients and their HLA-identical sibling donors of HSCs. FY genotyping was performed with the polymerase chain reaction-sequence-specific primer method and donor/recipient disparity for these antigens was analyzed at two levels: incompatibility and nonidentity. The case-control analyses showed no significant correlation between FY disparity and the incidence of either acute or chronic GVHD. Sample size calculation showed that 572 cases and 1716 controls would be necessary to be able to detect a significant association with 80% power and two-sided type I error level of 5% (α=0.05). The lack of association in the studied cohort may be explained by the low immunogenicity of FY antigens in HSCT context, compared with other antigens such as HA-1 and CD31.

  15. CD133 antigen expression in ovarian cancer

    Directory of Open Access Journals (Sweden)

    Prisco Maria

    2009-07-01

    Full Text Available Abstract Background Much attention has been recently focused on the role of cancer stem cells (CSCs in the initiation and progression of solid malignancies. Since CSCs are able to proliferate and self-renew extensively, thus sustaining tumor growth, the identification of CSCs through their antigenic profile might have relevant clinical implications. In this context, CD133 antigen has proved to be a marker of tumor cells with stemness features in several human malignancies. The aim of the study was to investigate the clinical role of the immunohistochemically assessed expression of CD133 in a large single Institution series of ovarian cancer patients. Methods The study included 160 cases admitted to the Gynecologic Oncology Unit, Catholic University of Campobasso and Rome. CD133 antigen was identified by the monoclonal mouse anti-CD133-1 antibody (clone CD133 Miltenyi biotec. Results In the overall series CD133 positive tumor cells were observed in 50/160 (31.2% cases. A diffuse cytoplasmic pattern was identified in 30/50 (60.0%, while an apical cytoplasmic pattern was found in 20/50 (40.0% of CD133 positive tumors. As of September 2008, the median follow up was 37 months (range: 2–112. During the follow up period, progression and death of disease were observed in 123 (76.9%, and 88 (55.0% cases, respectively. There was no difference in TTP between cases with negative (median TTP = 23 months versus positive CD133 expression (median TTP = 24 months (p value = 0.3. Similar results were obtained for OS. When considering the TTP and OS curves according to the pattern of CD133 expression, a trend to a worse prognosis for cases with diffuse cytoplasmic versus the apical cytoplasmic pattern was documented, although the statistical significance was not reached. Conclusion The immunohistochemical assessment of CD133 expression seems not to provide additional prognostic information in ovarian cancer patients. The role of the different pattern of CD133

  16. A universal computational model for predicting antigenic variants of influenza A virus based on conserved antigenic structures

    Science.gov (United States)

    Peng, Yousong; Wang, Dayan; Wang, Jianhong; Li, Kenli; Tan, Zhongyang; Shu, Yuelong; Jiang, Taijiao

    2017-01-01

    Rapid determination of the antigenicity of influenza A virus could help identify the antigenic variants in time. Currently, there is a lack of computational models for predicting antigenic variants of some common hemagglutinin (HA) subtypes of influenza A viruses. By means of sequence analysis, we demonstrate here that multiple HA subtypes of influenza A virus undergo similar mutation patterns of HA1 protein (the immunogenic part of HA). Further analysis on the antigenic variation of influenza A virus H1N1, H3N2 and H5N1 showed that the amino acid residues’ contribution to antigenic variation highly differed in these subtypes, while the regional bands, defined based on their distance to the top of HA1, played conserved roles in antigenic variation of these subtypes. Moreover, the computational models for predicting antigenic variants based on regional bands performed much better in the testing HA subtype than those did based on amino acid residues. Therefore, a universal computational model, named PREDAV-FluA, was built based on the regional bands to predict the antigenic variants for all HA subtypes of influenza A viruses. The model achieved an accuracy of 0.77 when tested with avian influenza H9N2 viruses. It may help for rapid identification of antigenic variants in influenza surveillance. PMID:28165025

  17. Facts on the fragmentation of antigens in presenting cells, on the association of antigen fragments with MHC molecules in cell-free systems, and speculation on the cell biology of antigen processing

    DEFF Research Database (Denmark)

    Werdelin, O; Mouritsen, S; Petersen, B L;

    1988-01-01

    The processing of a protein antigen is a multi-step event taking place in antigen-presenting cells. Processing is a prerequisite for the recognition of most antigens by T lymphocytes. The antigen is ingested by endocytosis, transported to an acid cellular compartment and subjected to proteolytic ...

  18. A Role For Mitochondria In Antigen Processing And Presentation.

    Science.gov (United States)

    Bonifaz, Lc; Cervantes-Silva, Mp; Ontiveros-Dotor, E; López-Villegas, Eo; Sánchez-García, Fj

    2014-09-23

    Immune synapse formation is critical for T lymphocyte activation, and mitochondria have a role in this process, by localizing close to the immune synapse, regulating intracellular calcium concentration, and providing locally required ATP. The interaction between antigen presenting cells (APCs) and T lymphocytes is a two-way signaling process. However, the role of mitochondria in antigen presenting cells during this process remains unknown. For APCs to be able to activate T lymphocytes, they must first engage in an antigen-uptake, -processing, and -presentation process. Here we show that HEL-loaded B lymphocytes, as a type of APCs, undergo a small but significant mitochondrial depolarization by 1-2 h following antigen exposure thus suggesting an increase in their metabolic demands. Inhibition of ATP synthase (oligomycin) or mitochondrial Ca(2+) uniporter (MCU) (Ruthenium red) had no effect on antigen uptake. Therefore, antigen processing and antigen presentation were further analyzed. Oligomycin treatment reduced the amount of specific MHC-peptide complexes but not total MHC II on the cell membrane of B lymphocytes which correlated with a decrease in antigen presentation. However, oligomycin also reduced antigen presentation by B lymphocytes that endogenously express HEL and by B lymphocytes loaded with the HEL48-62 peptide, although to a lesser extent. ATP synthase inhibition and MCU inhibition had a clear inhibitory effect on antigen processing (DQ-OVA). Taking together these results suggest that ATP synthase and MCU are relevant for antigen processing and presentation. Finally, APCs mitochondria were found to re-organize towards the APC-T immune synapse. This article is protected by copyright. All rights reserved.

  19. Use of antigenic cartography in vaccine seed strain selection.

    Science.gov (United States)

    Fouchier, Ron A M; Smith, Derek J

    2010-03-01

    Human influenza A viruses are classic examples of antigenically variable pathogens that have a seemingly endless capacity to evade the host's immune response. The viral hemagglutinin (HA) and neuraminidase (NA) proteins are the main targets of our antibody response to combat infections. HA and NA continuously change to escape from humoral immunity, a process known as antigenic drift. As a result of antigenic drift, the human influenza vaccine is updated frequently. The World Health Organization (WHO) coordinates a global influenza surveillance network that, by the hemagglutination inhibition (HI) assay, routinely characterizes the antigenic properties of circulating strains in order to select new seed viruses for such vaccine updates. To facilitate a quantitative interpretation and easy visualization of HI data, a new computational technique called "antigenic cartography" was developed. Since its development, antigenic cartography has been applied routinely to assist the WHO with influenza surveillance activities. Until recently, antigenic variation was not considered a serious issue with influenza vaccines for poultry. However, because of the diversification of the Asian H5N1 lineage since 1996 into multiple genetic clades and subclades, and because of the long-term use of poultry vaccines against H5 in some parts of the world, this issue needs to be re-addressed. The antigenic properties of panels of avian H5N1 viruses were characterized by HI assay, using mammalian or avian antisera, and analyzed using antigenic cartography methods. These analyses revealed antigenic differences between circulating H5N1 viruses and the H5 viruses used in poultry vaccines. Considerable antigenic variation was also observed within and between H5N1 clades. These observations have important implications for the efficacy and long-term use of poultry vaccines.

  20. Engineering antigen-specific immunological tolerance.

    Energy Technology Data Exchange (ETDEWEB)

    Kontos, Stephan; Grimm, Alizee J.; Hubbell, Jeffrey A.

    2015-05-01

    Unwanted immunity develops in response to many protein drugs, in autoimmunity, in allergy, and in transplantation. Approaches to induce immunological tolerance aim to either prevent these responses or reverse them after they have already taken place. We present here recent developments in approaches, based on engineered peptides, proteins and biomaterials, that harness mechanisms of peripheral tolerance both prophylactically and therapeutically to induce antigenspecific immunological tolerance. These mechanisms are based on responses of B and T lymphocytes to other cells in their immune environment that result in cellular deletion or ignorance to particular antigens, or in development of active immune regulatory responses. Several of these approaches are moving toward clinical development, and some are already in early stages of clinical testing.