WorldWideScience

Sample records for sialylated non-gpi-anchored surface

  1. GPI-anchored protein organization and dynamics at the cell surface.

    Science.gov (United States)

    Saha, Suvrajit; Anilkumar, Anupama Ambika; Mayor, Satyajit

    2016-02-01

    The surface of eukaryotic cells is a multi-component fluid bilayer in which glycosylphosphatidylinositol (GPI)-anchored proteins are an abundant constituent. In this review, we discuss the complex nature of the organization and dynamics of GPI-anchored proteins at multiple spatial and temporal scales. Different biophysical techniques have been utilized for understanding this organization, including fluorescence correlation spectroscopy, fluorescence recovery after photobleaching, single particle tracking, and a number of super resolution methods. Major insights into the organization and dynamics have also come from exploring the short-range interactions of GPI-anchored proteins by fluorescence (or Förster) resonance energy transfer microscopy. Based on the nanometer to micron scale organization, at the microsecond to the second time scale dynamics, a picture of the membrane bilayer emerges where the lipid bilayer appears inextricably intertwined with the underlying dynamic cytoskeleton. These observations have prompted a revision of the current models of plasma membrane organization, and suggest an active actin-membrane composite. Copyright © 2016 by the American Society for Biochemistry and Molecular Biology, Inc.

  2. Proteomic analysis of GPI-anchored membrane proteins

    DEFF Research Database (Denmark)

    Jung, Hye Ryung; Jensen, Ole Nørregaard

    2006-01-01

    Glycosyl-phosphatidyl-inositol-anchored proteins (GPI-APs) represent a subset of post-translationally modified proteins that are tethered to the outer leaflet of the plasma membrane via a C-terminal GPI anchor. GPI-APs are found in a variety of eukaryote species, from pathogenic microorganisms...... to humans. GPI-APs confer important cellular functions as receptors, enzymes and scaffolding molecules. Specific enzymes and detergent extraction methods combined with separation technologies and mass spectrometry permit proteomic analysis of GPI-APs from plasma membrane preparations to reveal cell...

  3. GPI-anchored proteins are confined in subdiffraction clusters at the apical surface of polarized epithelial cells.

    Science.gov (United States)

    Paladino, Simona; Lebreton, Stéphanie; Lelek, Mickaël; Riccio, Patrizia; De Nicola, Sergio; Zimmer, Christophe; Zurzolo, Chiara

    2017-12-01

    Spatio-temporal compartmentalization of membrane proteins is critical for the regulation of diverse vital functions in eukaryotic cells. It was previously shown that, at the apical surface of polarized MDCK cells, glycosylphosphatidylinositol (GPI)-anchored proteins (GPI-APs) are organized in small cholesterol-independent clusters of single GPI-AP species (homoclusters), which are required for the formation of larger cholesterol-dependent clusters formed by multiple GPI-AP species (heteroclusters). This clustered organization is crucial for the biological activities of GPI-APs; hence, understanding the spatio-temporal properties of their membrane organization is of fundamental importance. Here, by using direct stochastic optical reconstruction microscopy coupled to pair correlation analysis (pc-STORM), we were able to visualize and measure the size of these clusters. Specifically, we show that they are non-randomly distributed and have an average size of 67 nm. We also demonstrated that polarized MDCK and non-polarized CHO cells have similar cluster distribution and size, but different sensitivity to cholesterol depletion. Finally, we derived a model that allowed a quantitative characterization of the cluster organization of GPI-APs at the apical surface of polarized MDCK cells for the first time. Experimental FRET (fluorescence resonance energy transfer)/FLIM (fluorescence-lifetime imaging microscopy) data were correlated to the theoretical predictions of the model. © 2017 The Author(s).

  4. Mutational analysis of the glycosylphosphatidylinositol (GPI) anchor pathway demonstrates that GPI-anchored proteins are required for cell wall biogenesis and normal hyphal growth in Neurospora crassa.

    Science.gov (United States)

    Bowman, Shaun M; Piwowar, Amy; Al Dabbous, Mash'el; Vierula, John; Free, Stephen J

    2006-03-01

    Using mutational and proteomic approaches, we have demonstrated the importance of the glycosylphosphatidylinositol (GPI) anchor pathway for cell wall synthesis and integrity and for the overall morphology of the filamentous fungus Neurospora crassa. Mutants affected in the gpig-1, gpip-1, gpip-2, gpip-3, and gpit-1 genes, which encode components of the N. crassa GPI anchor biosynthetic pathway, have been characterized. GPI anchor mutants exhibit colonial morphologies, significantly reduced rates of growth, altered hyphal growth patterns, considerable cellular lysis, and an abnormal "cell-within-a-cell" phenotype. The mutants are deficient in the production of GPI-anchored proteins, verifying the requirement of each altered gene for the process of GPI-anchoring. The mutant cell walls are abnormally weak, contain reduced amounts of protein, and have an altered carbohydrate composition. The mutant cell walls lack a number of GPI-anchored proteins, putatively involved in cell wall biogenesis and remodeling. From these studies, we conclude that the GPI anchor pathway is critical for proper cell wall structure and function in N. crassa.

  5. Plant glycosylphosphatidylinositol (GPI) anchored proteins at the plasma membrane-cell wall nexus.

    Science.gov (United States)

    Yeats, Trevor H; Bacic, Antony; Johnson, Kim L

    2018-04-18

    Approximately 1% of plant proteins are predicted to be post-translationally modified with a glycosylphosphatidylinositol (GPI) anchor that tethers the polypeptide to the outer leaflet of the plasma membrane. While the synthesis and structure of GPI anchors is largely conserved across eukaryotes, the repertoire of functional domains present in the GPI-anchored proteome has diverged substantially. In plants, this includes a large fraction of the GPI-anchored proteome being further modified with plant-specific arabinogalactan (AG) O-glycans. The importance of the GPI-anchored proteome to plant development is underscored by the fact that GPI biosynthetic null mutants exhibit embryo lethality. Mutations in genes encoding specific GPI-anchored proteins (GAPs) further supports their contribution to diverse biological processes occurring at the interface of the plasma membrane and cell wall, including signaling, cell wall metabolism, cell wall polymer cross-linking, and plasmodesmatal transport. Here, we review the literature concerning plant GPI-anchored proteins in the context of their potential to act as molecular hubs that mediate interactions between the plasma membrane and the cell wall and their potential to transduce the signal into the protoplast and thereby activate signal transduction pathways. This article is protected by copyright. All rights reserved.

  6. Spontaneous insertion of GPI anchors into cholesterol-rich membrane domains

    Directory of Open Access Journals (Sweden)

    Jing Li

    2018-05-01

    Full Text Available GPI-Anchored proteins (GPI-APs can be exogenously transferred onto bilayer membranes both in vivo and in vitro, while the mechanism by which this transfer process occurs is unknown. In this work, we used atomistic molecular dynamics simulations and free energy calculations to characterize the essential influence of cholesterol on insertion of the GPI anchors into plasma membranes. We demonstrate, both dynamically and energetically, that in the presence of cholesterol, the tails of GPI anchors are able to penetrate inside the core of the lipid membrane spontaneously with a three-step mechanism, while in the absence of cholesterol no spontaneous insertion was observed. We ascribe the failure of insertion to the strong thermal fluctuation of lipid molecules in cholesterol-free bilayer, which generates a repulsive force in entropic origin. In the presence of cholesterol, however, the fluctuation of lipids is strongly reduced, thus decreasing the barrier for the anchor insertion. Based on this observation, we propose a hypothesis that addition of cholesterol creates vertical creases in membranes for the insertion of acyl chains. Moreover, we find that the GPI anchor could also spontaneously inserted into the boundary between cholesterol-rich and cholesterol-depleted domains. Our results shed light on the mechanism of cholesterol-mediated interaction between membrane proteins with acyl chain and plasma membranes in living cells.

  7. Spontaneous insertion of GPI anchors into cholesterol-rich membrane domains

    Science.gov (United States)

    Li, Jing; Liu, Xiuhua; Tian, Falin; Yue, Tongtao; Zhang, Xianren; Cao, Dapeng

    2018-05-01

    GPI-Anchored proteins (GPI-APs) can be exogenously transferred onto bilayer membranes both in vivo and in vitro, while the mechanism by which this transfer process occurs is unknown. In this work, we used atomistic molecular dynamics simulations and free energy calculations to characterize the essential influence of cholesterol on insertion of the GPI anchors into plasma membranes. We demonstrate, both dynamically and energetically, that in the presence of cholesterol, the tails of GPI anchors are able to penetrate inside the core of the lipid membrane spontaneously with a three-step mechanism, while in the absence of cholesterol no spontaneous insertion was observed. We ascribe the failure of insertion to the strong thermal fluctuation of lipid molecules in cholesterol-free bilayer, which generates a repulsive force in entropic origin. In the presence of cholesterol, however, the fluctuation of lipids is strongly reduced, thus decreasing the barrier for the anchor insertion. Based on this observation, we propose a hypothesis that addition of cholesterol creates vertical creases in membranes for the insertion of acyl chains. Moreover, we find that the GPI anchor could also spontaneously inserted into the boundary between cholesterol-rich and cholesterol-depleted domains. Our results shed light on the mechanism of cholesterol-mediated interaction between membrane proteins with acyl chain and plasma membranes in living cells.

  8. Data for identification of GPI-anchored peptides and ω-sites in cancer cell lines

    Directory of Open Access Journals (Sweden)

    Yusuke Masuishi

    2016-06-01

    Full Text Available We present data obtained using a focused proteomics approach to identify the glycosylphosphatidylinositol (GPI-anchored peptides in 19 human cancer cell lines. GPI-anchored proteins (GPI-APs, which localize to the outer leaflet of the membrane microdomains commonly referred to as lipid rafts play important roles in diverse biological processes. Due to the complex structure of the GPI-anchor moiety, it has been difficult to identify GPI-anchored peptide sequences on the proteomic scale by database searches using tools such as MASCOT. Here we provide data from 73 ω-sites derived from 49 GPI-APs in 19 human cancer cell lines. This article contains data related to the research article entitled “Identification of glycosylphosphatidylinositol-anchored proteins and ω-sites using TiO2-based affinity purification followed by hydrogen fluoride treatment” (Masuishi et al., 2016 [1].

  9. Chemical biology of Glycosylphosphatidylinositol (GPI) anchors

    Indian Academy of Sciences (India)

    Admin

    CSIR-IIIM. Chemical biology of. Glycosylphosphatidylinositol (GPI) anchors. Ram Vishwakarma. CSIR-Indian Institute of Integrative Medicine, Jammu. N ti l I tit t f I l. N. D lhi. National Institute of Immunology, New Delhi. Piramal Life Sciences Ltd, Mumbai ...

  10. Targeting the GPI biosynthetic pathway.

    Science.gov (United States)

    Yadav, Usha; Khan, Mohd Ashraf

    2018-02-27

    The GPI (Glycosylphosphatidylinositol) biosynthetic pathway is a multistep conserved pathway in eukaryotes that culminates in the generation of GPI glycolipid which in turn anchors many proteins (GPI-APs) to the cell surface. In spite of the overall conservation of the pathway, there still exist subtle differences in the GPI pathway of mammals and other eukaryotes which holds a great promise so far as the development of drugs/inhibitors against specific targets in the GPI pathway of pathogens is concerned. Many of the GPI structures and their anchored proteins in pathogenic protozoans and fungi act as pathogenicity factors. Notable examples include GPI-anchored variant surface glycoprotein (VSG) in Trypanosoma brucei, GPI-anchored merozoite surface protein 1 (MSP1) and MSP2 in Plasmodium falciparum, protein-free GPI related molecules like lipophosphoglycans (LPGs) and glycoinositolphospholipids (GIPLs) in Leishmania spp., GPI-anchored Gal/GalNAc lectin and proteophosphoglycans in Entamoeba histolytica or the GPI-anchored mannoproteins in pathogenic fungi like Candida albicans. Research in this active area has already yielded encouraging results in Trypanosoma brucei by the development of parasite-specific inhibitors of GlcNCONH 2 -β-PI, GlcNCONH 2 -(2-O-octyl)-PI and salicylic hydroxamic acid (SHAM) targeting trypanosomal GlcNAc-PI de-N-acetylase as well as the development of antifungal inhibitors like BIQ/E1210/gepinacin/G365/G884 and YW3548/M743/M720 targeting the GPI specific fungal inositol acyltransferase (Gwt1) and the phosphoethanolamine transferase-I (Mcd4), respectively. These confirm the fact that the GPI pathway continues to be the focus of researchers, given its implications for the betterment of human life.

  11. Display of GPI-anchored anti-EGFR nanobodies on extracellular vesicles promotes tumour cell targeting

    Directory of Open Access Journals (Sweden)

    Sander A. A. Kooijmans

    2016-03-01

    Full Text Available Background: Extracellular vesicles (EVs are attractive candidate drug delivery systems due to their ability to functionally transport biological cargo to recipient cells. However, the apparent lack of target cell specificity of exogenously administered EVs limits their therapeutic applicability. In this study, we propose a novel method to equip EVs with targeting properties, in order to improve their interaction with tumour cells. Methods: EV producing cells were transfected with vectors encoding for anti-epidermal growth factor receptor (EGFR nanobodies, which served as targeting ligands for tumour cells, fused to glycosylphosphatidylinositol (GPI anchor signal peptides derived from decay-accelerating factor (DAF. EVs were isolated using ultrafiltration/size-exclusion liquid chromatography and characterized using western blotting, Nanoparticle Tracking Analysis, and electron microscopy. EV–tumour cell interactions were analyzed under static conditions using flow cytometry and under flow conditions using a live-cell fluorescence microscopy-coupled perfusion system. Results: V analysis showed that GPI-linked nanobodies were successfully displayed on EV surfaces and were highly enriched in EVs compared with parent cells. Display of GPI-linked nanobodies on EVs did not alter general EV characteristics (i.e. morphology, size distribution and protein marker expression, but greatly improved EV binding to tumour cells dependent on EGFR density under static conditions. Moreover, nanobody-displaying EVs showed a significantly improved cell association to EGFR-expressing tumour cells under flow conditions. Conclusions: We show that nanobodies can be anchored on the surface of EVs via GPI, which alters their cell targeting behaviour. Furthermore, this study highlights GPI-anchoring as a new tool in the EV toolbox, which may be applied for EV display of a variety of proteins, such as antibodies, reporter proteins and signaling molecules.

  12. Use of green fluorescent protein fusions to analyse the N- and C-terminal signal peptides of GPI-anchored cell wall proteins in Candida albicans.

    Science.gov (United States)

    Mao, Yuxin; Zhang, Zimei; Wong, Brian

    2003-12-01

    Glycophosphatidylinositol (GPI)-anchored proteins account for 26-35% of the Candida albicans cell wall. To understand the signals that regulate these proteins' cell surface localization, green fluorescent protein (GFP) was fused to the N- and C-termini of the C. albicans cell wall proteins (CWPs) Hwp1p, Als3p and Rbt5p. C. albicans expressing all three fusion proteins were fluorescent at the cell surface. GFP was released from membrane fractions by PI-PLC and from cell walls by beta-glucanase, which implied that GFP was GPI-anchored to the plasma membrane and then covalently attached to cell wall glucans. Twenty and 25 amino acids, respectively, from the N- and C-termini of Hwp1p were sufficient to target GFP to the cell surface. C-terminal substitutions that are permitted by the omega rules (G613D, G613N, G613S, G613A, G615S) did not interfere with GFP localization, whereas some non-permitted substitutions (G613E, G613Q, G613R, G613T and G615Q) caused GFP to accumulate in intracellular ER-like structures and others (G615C, G613N/G615C and G613D/G615C) did not. These results imply that (i) GFP fusions can be used to analyse the N- and C-terminal signal peptides of GPI-anchored CWPs, (ii) the omega amino acid in Hwp1p is G613, and (iii) C can function at the omega+2 position in C. albicans GPI-anchored proteins.

  13. A Tenebrio molitor GPI-anchored alkaline phosphatase is involved in binding of Bacillus thuringiensis Cry3Aa to brush border membrane vesicles.

    Science.gov (United States)

    Zúñiga-Navarrete, Fernando; Gómez, Isabel; Peña, Guadalupe; Bravo, Alejandra; Soberón, Mario

    2013-03-01

    Bacillus thuringiensis Cry toxins recognizes their target cells in part by the binding to glycosyl-phosphatidyl-inositol (GPI) anchored proteins such as aminopeptidase-N (APN) or alkaline phosphatases (ALP). Treatment of Tenebrio molitor brush border membrane vesicles (BBMV) with phospholipase C that cleaves out GPI-anchored proteins from the membranes, showed that GPI-anchored proteins are involved in binding of Cry3Aa toxin to BBMV. A 68 kDa GPI-anchored ALP was shown to bind Cry3Aa by toxin overlay assays. The 68 kDa GPI-anchored ALP was preferentially expressed in early instar larvae in comparison to late instar larvae. Our work shows for the first time that GPI-anchored ALP is important for Cry3Aa binding to T. molitor BBMV suggesting that the mode of action of Cry toxins is conserved in different insect orders. Copyright © 2012 Elsevier Inc. All rights reserved.

  14. Hypomorphic mutations in PGAP2, encoding a GPI-anchor-remodeling protein, cause autosomal-recessive intellectual disability

    DEFF Research Database (Denmark)

    Hansen, Lars; Tawamie, Hasan; Murakami, Yoshiko

    2013-01-01

    PGAP2 encodes a protein involved in remodeling the glycosylphosphatidylinositol (GPI) anchor in the Golgi apparatus. After synthesis in the endoplasmic reticulum (ER), GPI anchors are transferred to the proteins and are remodeled while transported through the Golgi to the cell membrane. Germline...... mutations in six genes (PIGA, PIGL, PIGM, PIGV, PIGN, and PIGO) in the ER-located part of the GPI-anchor-biosynthesis pathway have been reported, and all are associated with phenotypes extending from malformation and lethality to severe intellectual disability, epilepsy, minor dysmorphisms, and elevated...... alkaline phosphatase (ALP). We performed autozygosity mapping and ultra-deep sequencing followed by stringent filtering and identified two homozygous PGAP2 alterations, p.Tyr99Cys and p.Arg177Pro, in seven offspring with nonspecific autosomal-recessive intellectual disability from two consanguineous...

  15. GPI anchor biosynthesis in yeast : phosphoethanolamine is attached to the alpha1,4-linked mannose of the complete precursor glycophospholipid

    NARCIS (Netherlands)

    Canivenc-Gansel, E; Imhof, I; Reggiori, F; Burda, P; Conzelmann, A; Benachour, A; Reggiori, Fulvio

    Cells synthesize the GPI anchor carbohydrate core by successively adding N-acetylglucosamine, three mannoses, and phosphoethanolamine (EtN-P) onto phosphatidylinositol, thus forming the complete GPI precursor lipid which is then added to proteins. Previously, we isolated a GPI deficient yeast mutant

  16. Apical sorting of lysoGPI-anchored proteins occurs independent of association with detergent-resistant membranes but dependent on their N-glycosylation.

    Science.gov (United States)

    Castillon, Guillaume Alain; Michon, Laetitia; Watanabe, Reika

    2013-06-01

    Most glycosylphosphatidylinositol-anchored proteins (GPI-APs) are located at the apical surface of epithelial cells. The apical delivery of GPI-APs is believed to result from their association with lipid rafts. We find that overexpression of C-terminally tagged PGAP3 caused predominant production of lysoGPI-APs, an intermediate precursor in the GPI lipid remodeling process in Madin-Darby canine kidney cells. In these cells, produced lysoGPI-APs are not incorporated into detergent-resistant membranes (DRMs) but still are delivered apically, suggesting that GPI-AP association with DRMs is not necessary for apical targeting. In contrast, apical transport of both fully remodeled and lyso forms of GPI-APs is dependent on N-glycosylation, confirming a general role of N-glycans in apical protein transport. We also find that depletion of cholesterol causes apical-to-basolateral retargeting not only of fully remodeled GPI-APs, but also of lysoGPI-APs, as well as endogenous soluble and transmembrane proteins that would normally be targeted to the apical membrane. These findings confirm the essential role for cholesterol in the apical protein targeting and further demonstrate that the mechanism of cholesterol-dependent apical sorting is not related to DRM association of GPI-APs.

  17. Two endoplasmic reticulum (ER) membrane proteins that facilitate ER-to-Golgi transport of glycosylphosphatidylinositol-anchored proteins.

    Science.gov (United States)

    Barz, W P; Walter, P

    1999-04-01

    Many eukaryotic cell surface proteins are anchored in the lipid bilayer through glycosylphosphatidylinositol (GPI). GPI anchors are covalently attached in the endoplasmic reticulum (ER). The modified proteins are then transported through the secretory pathway to the cell surface. We have identified two genes in Saccharomyces cerevisiae, LAG1 and a novel gene termed DGT1 (for "delayed GPI-anchored protein transport"), encoding structurally related proteins with multiple membrane-spanning domains. Both proteins are localized to the ER, as demonstrated by immunofluorescence microscopy. Deletion of either gene caused no detectable phenotype, whereas lag1Delta dgt1Delta cells displayed growth defects and a significant delay in ER-to-Golgi transport of GPI-anchored proteins, suggesting that LAG1 and DGT1 encode functionally redundant or overlapping proteins. The rate of GPI anchor attachment was not affected, nor was the transport rate of several non-GPI-anchored proteins. Consistent with a role of Lag1p and Dgt1p in GPI-anchored protein transport, lag1Delta dgt1Delta cells deposit abnormal, multilayered cell walls. Both proteins have significant sequence similarity to TRAM, a mammalian membrane protein thought to be involved in protein translocation across the ER membrane. In vivo translocation studies, however, did not detect any defects in protein translocation in lag1Delta dgt1Delta cells, suggesting that neither yeast gene plays a role in this process. Instead, we propose that Lag1p and Dgt1p facilitate efficient ER-to-Golgi transport of GPI-anchored proteins.

  18. Novel applications for glycosylphosphatidylinositol-anchored proteins in pharmaceutical and industrial biotechnology.

    Science.gov (United States)

    Müller, Günter

    2011-04-01

    Glycosylphosphatidylinositol (GPI)-anchored proteins have been regarded as typical cell surface proteins found in most eukaryotic cells from yeast to man. They are embedded in the outer plasma membrane leaflet via a carboxy-terminally linked complex glycolipid GPI structure. The amphiphilic nature of the GPI anchor, its compatibility with the function of the attached protein moiety and the capability of GPI-anchored proteins for spontaneous insertion into and transfer between artificial and cellular membranes initially suggested their potential for biotechnological applications. However, these expectations have been hardly fulfilled so far. Recent developments fuel novel hopes with regard to: (i) Automated online expression, extraction and purification of therapeutic proteins as GPI-anchored proteins based on their preferred accumulation in plasma membrane lipid rafts, (ii) multiplex custom-made protein chips based on GPI-anchored cell wall proteins in yeast, (iii) biomaterials and biosensors with films consisting of sets of distinct GPI-anchored binding-proteins or enzymes for sequential or combinatorial catalysis, and (iv) transport of therapeutic proteins across or into relevant tissue cells, e.g., enterocytes or adipocytes. Latter expectations are based on the demonstrated translocation of GPI-anchored proteins from plasma membrane lipid rafts to cytoplasmic lipid droplets and eventually further into microvesicles which upon release from donor cells transfer their GPI-anchored proteins to acceptor cells. The value of these technologies, which are all based on the interaction of GPI-anchored proteins with membranes and surfaces, for the engineering, production and targeted delivery of biomolecules for a huge variety of therapeutic and biotechnological purposes should become apparent in the near future.

  19. Cytosolically expressed PrP GPI-signal peptide interacts with mitochondria.

    Science.gov (United States)

    Guizzunti, Gianni; Zurzolo, Chiara

    2015-01-01

    We previously reported that PrP GPI-anchor signal peptide (GPI-SP) is specifically degraded by the proteasome. Additionally, we showed that the point mutation P238S, responsible for a genetic form of prion diseases, while not affecting the GPI-anchoring process, results in the accumulation of PrP GPI-SP, suggesting the possibility that PrP GPI-anchor signal peptide could play a role in neurodegenerative prion diseases. We now show that PrP GPI-SP, when expressed as a cytosolic peptide, is able to localize to the mitochondria and to induce mitochondrial fragmentation and vacuolarization, followed by loss in mitochondrial membrane potential, ultimately resulting in apoptosis. Our results identify the GPI-SP of PrP as a novel candidate responsible for the impairment in mitochondrial function involved in the synaptic pathology observed in prion diseases, establishing a link between PrP GPI-SP accumulation and neuronal death.

  20. A Multifaceted Study of Scedosporium boydii Cell Wall Changes during Germination and Identification of GPI-Anchored Proteins

    Science.gov (United States)

    Ghamrawi, Sarah; Gastebois, Amandine; Zykwinska, Agata; Vandeputte, Patrick; Marot, Agnès; Mabilleau, Guillaume; Cuenot, Stéphane; Bouchara, Jean-Philippe

    2015-01-01

    Scedosporium boydii is a pathogenic filamentous fungus that causes a wide range of human infections, notably respiratory infections in patients with cystic fibrosis. The development of new therapeutic strategies targeting S. boydii necessitates a better understanding of the physiology of this fungus and the identification of new molecular targets. In this work, we studied the conidium-to-germ tube transition using a variety of techniques including scanning and transmission electron microscopy, atomic force microscopy, two-phase partitioning, microelectrophoresis and cationized ferritin labeling, chemical force spectroscopy, lectin labeling, and nanoLC-MS/MS for cell wall GPI-anchored protein analysis. We demonstrated that the cell wall undergoes structural changes with germination accompanied with a lower hydrophobicity, electrostatic charge and binding capacity to cationized ferritin. Changes during germination also included a higher accessibility of some cell wall polysaccharides to lectins and less CH3/CH3 interactions (hydrophobic adhesion forces mainly due to glycoproteins). We also extracted and identified 20 GPI-anchored proteins from the cell wall of S. boydii, among which one was detected only in the conidial wall extract and 12 only in the mycelial wall extract. The identified sequences belonged to protein families involved in virulence in other fungi like Gelp/Gasp, Crhp, Bglp/Bgtp families and a superoxide dismutase. These results highlighted the cell wall remodeling during germination in S. boydii with the identification of a substantial number of cell wall GPI-anchored conidial or hyphal specific proteins, which provides a basis to investigate the role of these molecules in the host-pathogen interaction and fungal virulence. PMID:26038837

  1. Two homologous genes, DCW1 (YKL046c) and DFG5, are essential for cell growth and encode glycosylphosphatidylinositol (GPI)-anchored membrane proteins required for cell wall biogenesis in Saccharomyces cerevisiae.

    Science.gov (United States)

    Kitagaki, Hiroshi; Wu, Hong; Shimoi, Hitoshi; Ito, Kiyoshi

    2002-11-01

    The cell wall of Saccharomyces cerevisiae consists of glucan, chitin and various kinds of mannoproteins. Major parts of mannoproteins are synthesized as glycosylphosphatidylinositol (GPI)-anchored proteins and are then transferred to cell wall beta-1,6-glucan. A glycosyltransferase has been hypothesized to catalyse this transfer reaction. A database search revealed that the products of YKL046c and DFG5 are homologous to bacterial mannosidase. These genes are homologous to each other and have primary structures characteristic of GPI-anchored proteins. Although single disruptants of ykl046c and dfg5 were viable, ykl046cDelta was hypersensitive to a cell wall-digesting enzyme (zymolyase), suggesting that this gene is involved in cell wall biosynthesis. We therefore designated this gene as DCW1 (defective cell wall). A double disruptant of dcw1 and dfg5 was synthetically lethal, indicating that the functions of these gene products are redundant, and at least one of them is required for cell growth. Cells deficient in both Dcw1p and Dfg5p were round and large, had cell walls that contained an increased amount of chitin and secreted a major cell wall protein, Cwp1p, into the medium. Biochemical analyses showed that epitope-tagged Dcw1p is an N-glycosylated, GPI-anchored membrane protein and is localized in the membrane fraction including the cell surface. These results suggest that both Dcw1p and Dfg5p are GPI-anchored membrane proteins and are required for normal biosynthesis of the cell wall.

  2. Glycosyl-phosphatidylinositol (GPI)-anchored membrane association of the porcine reproductive and respiratory syndrome virus GP4 glycoprotein and its co-localization with CD163 in lipid rafts

    Energy Technology Data Exchange (ETDEWEB)

    Du, Yijun [Department of Pathobiology, University of Illinois at Urbana-Champaign, 2001 South Lincoln Ave, Urbana, IL 61802 (United States); Shandong Key Laboratory of Animal Disease Control and Breeding, Institute of Animal Science and Veterinary Medicine, Shandong Academy of Agricultural Sciences, Jinan (China); Pattnaik, Asit K. [School of Veterinary Medicine and Biomedical Sciences and the Nebraska Center for Virology, University of Nebraska-Lincoln, Lincoln, NE 68583-0900 (United States); Song, Cheng [Department of Pathobiology, University of Illinois at Urbana-Champaign, 2001 South Lincoln Ave, Urbana, IL 61802 (United States); Yoo, Dongwan, E-mail: dyoo@illinois.edu [Department of Pathobiology, University of Illinois at Urbana-Champaign, 2001 South Lincoln Ave, Urbana, IL 61802 (United States); Li, Gang, E-mail: dyoo@illinois.edu [Department of Pathobiology, University of Illinois at Urbana-Champaign, 2001 South Lincoln Ave, Urbana, IL 61802 (United States); Institute of Animal Science and Veterinary Medicine, Chinese Academy of Agricultural Sciences, Beijing (China)

    2012-03-01

    The porcine reproductive and respiratory syndrome virus (PRRSV) glycoprotein 4 (GP4) resembles a typical type I membrane protein in its structure but lacks a hydrophilic tail at the C-terminus, suggesting that GP4 may be a lipid-anchored membrane protein. Using the human decay-accelerating factor (DAF; CD55), a known glycosyl-phosphatidylinositol (GPI) lipid-anchored protein, chimeric constructs were made to substitute the GPI-anchor domain of DAF with the putative lipid-anchor domain of GP4, and their membrane association and lipase cleavage were determined in cells. The DAF-GP4 fusion protein was transported to the plasma membrane and was cleaved by phosphatidylinositol-specific phospholipase C (PI-PLC), indicating that the C-terminal domain of GP4 functions as a GPI anchor. Mutational studies for residues adjacent to the GPI modification site and characterization of respective mutant viruses generated from infectious cDNA clones show that the ability of GP4 for membrane association corresponded to virus viability and growth characteristics. The residues T158 ({omega} - 2, where {omega} is the GPI moiety at E160), P159 ({omega} - 1), and M162 ({omega} + 2) of GP4 were determined to be important for virus replication, with M162 being of particular importance for virus infectivity. The complete removal of the peptide-anchor domain in GP4 resulted in a complete loss of virus infectivity. The depletion of cholesterol from the plasma membrane of cells reduced the virus production, suggesting a role of lipid rafts in PRRSV infection. Remarkably, GP4 was found to co-localize with CD163 in the lipid rafts on the plasma membrane. Since CD163 has been reported as a cellular receptor for PRRSV and GP4 has been shown to interact with this receptor, our data implicates an important role of lipid rafts during entry of the virus.

  3. Glycosyl-phosphatidylinositol (GPI)-anchored membrane association of the porcine reproductive and respiratory syndrome virus GP4 glycoprotein and its co-localization with CD163 in lipid rafts

    International Nuclear Information System (INIS)

    Du, Yijun; Pattnaik, Asit K.; Song, Cheng; Yoo, Dongwan; Li, Gang

    2012-01-01

    The porcine reproductive and respiratory syndrome virus (PRRSV) glycoprotein 4 (GP4) resembles a typical type I membrane protein in its structure but lacks a hydrophilic tail at the C-terminus, suggesting that GP4 may be a lipid-anchored membrane protein. Using the human decay-accelerating factor (DAF; CD55), a known glycosyl-phosphatidylinositol (GPI) lipid-anchored protein, chimeric constructs were made to substitute the GPI-anchor domain of DAF with the putative lipid-anchor domain of GP4, and their membrane association and lipase cleavage were determined in cells. The DAF-GP4 fusion protein was transported to the plasma membrane and was cleaved by phosphatidylinositol-specific phospholipase C (PI-PLC), indicating that the C-terminal domain of GP4 functions as a GPI anchor. Mutational studies for residues adjacent to the GPI modification site and characterization of respective mutant viruses generated from infectious cDNA clones show that the ability of GP4 for membrane association corresponded to virus viability and growth characteristics. The residues T158 (ω − 2, where ω is the GPI moiety at E160), P159 (ω − 1), and M162 (ω + 2) of GP4 were determined to be important for virus replication, with M162 being of particular importance for virus infectivity. The complete removal of the peptide–anchor domain in GP4 resulted in a complete loss of virus infectivity. The depletion of cholesterol from the plasma membrane of cells reduced the virus production, suggesting a role of lipid rafts in PRRSV infection. Remarkably, GP4 was found to co-localize with CD163 in the lipid rafts on the plasma membrane. Since CD163 has been reported as a cellular receptor for PRRSV and GP4 has been shown to interact with this receptor, our data implicates an important role of lipid rafts during entry of the virus.

  4. Defects in GPI biosynthesis perturb Cripto signaling during forebrain development in two new mouse models of holoprosencephaly

    Directory of Open Access Journals (Sweden)

    David M. McKean

    2012-07-01

    Holoprosencephaly is the most common forebrain defect in humans. We describe two novel mouse mutants that display a holoprosencephaly-like phenotype. Both mutations disrupt genes in the glycerophosphatidyl inositol (GPI biosynthesis pathway: gonzo disrupts Pign and beaker disrupts Pgap1. GPI anchors normally target and anchor a diverse group of proteins to lipid raft domains. Mechanistically we show that GPI anchored proteins are mislocalized in GPI biosynthesis mutants. Disruption of the GPI-anchored protein Cripto (mouse and TDGF1 (human ortholog have been shown to result in holoprosencephaly, leading to our hypothesis that Cripto is the key GPI anchored protein whose altered function results in an HPE-like phenotype. Cripto is an obligate Nodal co-factor involved in TGFβ signaling, and we show that TGFβ signaling is reduced both in vitro and in vivo. This work demonstrates the importance of the GPI anchor in normal forebrain development and suggests that GPI biosynthesis genes should be screened for association with human holoprosencephaly.

  5. Cleavage of ST6Gal I by Radiation-Induced BACE1 Inhibits Golgi-Anchored ST6Gal I-Mediated Sialylation of Integrin β1 and Migration in Colon Cancer Cells

    International Nuclear Information System (INIS)

    Lee, Minyoung; Park, Jung-Jin; Ko, Young-Gyu; Lee, Yun-Sil

    2012-01-01

    Previously, we found that β-galactoside α2,6-sialyltransferase (ST6Gal I), an enzyme that adds sialic acids to N-linked oligosaccharides of glycoproteins and is frequently overexpressed in cancer cells, is up-regulated by ionizing radiation (IR) and cleaved to a form possessing catalytic activity comparable to that of the Golgi-localized enzyme. Moreover, this soluble form is secreted into the culture media. Induction of ST6Gal I significantly increased the migration of colon cancer cells via sialylation of integrin β1. Here, we further investigated the mechanisms underlying ST6Gal I cleavage, solubilization and release from cells, and addressed its functions, focusing primarily on cancer cell migration. We performed immunoblotting and lectin affinity assay to analyze the expression of ST6 Gal I and level of sialylated integrin β1. After ionizing radiation, migration of cells was measured by in vitro migration assay. α2, 6 sialylation level of cell surface was analyzed by flow cytometry. Cell culture media were concentrated and then analyzed for soluble ST6Gal I levels using an α2, 6 sialyltransferase sandwich ELISA. We found that ST6Gal I was cleaved by BACE1 (β-site amyloid precursor protein-cleaving enzyme), which was specifically overexpressed in response to IR. The soluble form of ST6Gal I, which also has sialyltransferase enzymatic activity, was cleaved from the Golgi membrane and then released into the culture media. Both non-cleaved and cleaved forms of ST6Gal I significantly increased colon cancer cell migration in a sialylation-dependent manner. The pro-migratory effect of the non-cleaved form of ST6Gal I was dependent on integrin β1 sialylation, whereas that of the cleaved form of ST6Gal I was not, suggesting that other intracellular sialylated molecules apart from cell surface molecules such as integrin β1 might be involved in mediating the pro-migratory effects of the soluble form of ST6Gal I. Moreover, production of soluble form ST6Gal I by

  6. Glycolipid precursors for the membrane anchor of Trypanosoma brucei variant surface glycoproteins. II. Lipid structures of phosphatidylinositol-specific phospholipase C sensitive and resistant glycolipids

    International Nuclear Information System (INIS)

    Mayor, S.; Menon, A.K.; Cross, G.A.

    1990-01-01

    A common diagnostic feature of glycosylinositol phospholipid (GPI)-anchored proteins is their release from the membrane by a phosphatidylinositol-specific phospholipase C (PI-PLC). However, some GPI-anchored proteins are resistant to this enzyme. The best characterized example of this subclass is the human erythrocyte acetylcholinesterase, where the structural basis of PI-PLC resistance has been shown to be the acylation of an inositol hydroxyl group(s). Both PI-PLC-sensitive and resistant GPI-anchor precursors (P2 and P3, respectively) have been found in Trypanosoma brucei, where the major surface glycoprotein is anchored by a PI-PLC-sensitive glycolipid anchor. The accompanying paper shows that P2 and P3 have identical glycans, indistinguishable from the common core glycan found on all the characterized GPI protein anchors. This paper shows that the single difference between P2 and P3, and the basis for the PI-PLC insusceptibility of P3, is a fatty acid, ester-linked to the inositol residue in P3. The inositol-linked fatty acid can be removed by treatment with mild base to restore PI-PLC sensitivity. Biosynthetic labeling experiments with [3H]palmitic acid and [3H]myristic acid show that [3H]palmitic acid specifically labels the inositol residue in P3 while [3H]myristic acid labels the diacylglycerol portion. Possible models to account for the simultaneous presence of PI-PLC-resistant and sensitive glycolipids are discussed in the context of available information on the biosynthesis of GPI-anchors

  7. Diffusion of lipids and GPI-anchored proteins in actin-free plasma membrane vesicles measured by STED-FCS

    DEFF Research Database (Denmark)

    Schneider, Falk; Waithe, Dominic; Clausen, Mathias P

    2017-01-01

    (STED-FCS) to access and compare the diffusion characteristics of fluorescent lipid analogues and GPI-anchored proteins (GPI-APs) in the live cell plasma membrane and in actin cytoskeleton-free cell-derived giant plasma membrane vesicles (GPMVs). Hindered diffusion of phospholipids and sphingolipids......Diffusion and interaction dynamics of molecules at the plasma membrane play an important role in cellular signalling, and they are suggested to be strongly associated with the actin cytoskeleton. Here, we utilise super-resolution STED microscopy combined with fluorescence correlation spectroscopy...... forming immobile clusters, both of which disappear in GPMVs. Our data underline the crucial role of the actin cortex in maintaining hindered diffusion modes of many but not all of the membrane molecules, and highlight a powerful experimental approach to decipher specific influences on molecular plasma...

  8. Proteomic analysis of glycosylphosphatidylinositol-anchored membrane proteins

    DEFF Research Database (Denmark)

    Elortza, Felix; Nühse, Thomas S; Foster, Leonard J

    2003-01-01

    Glycosylphosphatidylinositol-anchored proteins (GPI-APs) are a functionally and structurally diverse family of post-translationally modified membrane proteins found mostly in the outer leaflet of the plasma membrane in a variety of eukaryotic cells. Although the general role of GPI-APs remains...... unclear, they have attracted attention because they act as enzymes and receptors in cell adhesion, differentiation, and host-pathogen interactions. GPI-APs may represent potential diagnostic and therapeutic targets in humans and are interesting in plant biotechnology because of their key role in root...... and 44 GPI-APs in an Arabidopsis thaliana membrane preparation, representing the largest experimental dataset of GPI-anchored proteins to date....

  9. Extraneural manifestations of prion infection in GPI-anchorless transgenic mice

    International Nuclear Information System (INIS)

    Lee, Andrew M.; Paulsson, Johan F.; Cruite, Justin; Andaya, Abegail A.; Trifilo, Matthew J.; Oldstone, Michael B.A.

    2011-01-01

    Earlier studies indicated that transgenic (tg) mice engineered to express prion protein (PrP) lacking the glycophosphatidylinositol (GPI -/- ) membrane anchor formed abnormal proteinase-resistant prion (PrPsc) amyloid deposits in their brains and hearts when infected with the RML strain of murine scrapie. In contrast, RML scrapie infection of normal mice with a GPI-anchored PrP did not deposit amyloid with PrPsc in the brain or the heart. Here we report that scrapie-infected GPI -/- PrP tg mice also deposit PrP and transmissible infectious material in the gut, kidneys, and islets of Langerhans. Similar to previously reported amyloid deposits in the brain and heart, amyloid deposits were found in the gut; however, no amyloid deposited in the islets. By high-resolution electron microscopy, we show PrP is located primarily in α cells and also β cells. Islets contain abundant insulin and there is no abnormality in glucose metabolism in infected GPI -/- PrP tg mice.

  10. Sialic Acid on the Glycosylphosphatidylinositol Anchor Regulates PrP-mediated Cell Signaling and Prion Formation.

    Science.gov (United States)

    Bate, Clive; Nolan, William; Williams, Alun

    2016-01-01

    The prion diseases occur following the conversion of the cellular prion protein (PrP(C)) into disease-related isoforms (PrP(Sc)). In this study, the role of the glycosylphosphatidylinositol (GPI) anchor attached to PrP(C) in prion formation was examined using a cell painting technique. PrP(Sc) formation in two prion-infected neuronal cell lines (ScGT1 and ScN2a cells) and in scrapie-infected primary cortical neurons was increased following the introduction of PrP(C). In contrast, PrP(C) containing a GPI anchor from which the sialic acid had been removed (desialylated PrP(C)) was not converted to PrP(Sc). Furthermore, the presence of desialylated PrP(C) inhibited the production of PrP(Sc) within prion-infected cortical neurons and ScGT1 and ScN2a cells. The membrane rafts surrounding desialylated PrP(C) contained greater amounts of sialylated gangliosides and cholesterol than membrane rafts surrounding PrP(C). Desialylated PrP(C) was less sensitive to cholesterol depletion than PrP(C) and was not released from cells by treatment with glimepiride. The presence of desialylated PrP(C) in neurons caused the dissociation of cytoplasmic phospholipase A2 from PrP-containing membrane rafts and reduced the activation of cytoplasmic phospholipase A2. These findings show that the sialic acid moiety of the GPI attached to PrP(C) modifies local membrane microenvironments that are important in PrP-mediated cell signaling and PrP(Sc) formation. These results suggest that pharmacological modification of GPI glycosylation might constitute a novel therapeutic approach to prion diseases. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

  11. Tritium labelling of a cholesterol amphiphile designed for cell membrane anchoring of proteins.

    Science.gov (United States)

    Schäfer, Balázs; Orbán, Erika; Kele, Zoltán; Tömböly, Csaba

    2015-01-01

    Cell membrane association of proteins can be achieved by the addition of lipid moieties to the polypeptide chain, and such lipid-modified proteins have important biological functions. A class of cell surface proteins contains a complex glycosylphosphatidylinositol (GPI) glycolipid at the C-terminus, and they are accumulated in cholesterol-rich membrane microdomains, that is, lipid rafts. Semisynthetic lipoproteins prepared from recombinant proteins and designed lipids are valuable probes and model systems of the membrane-associated proteins. Because GPI-anchored proteins can be reinserted into the cell membrane with the retention of the biological function, they are appropriate candidates for preparing models via reduction of the structural complexity. A synthetic headgroup was added to the 3β-hydroxyl group of cholesterol, an essential lipid component of rafts, and the resulting cholesterol derivative was used as a simplified GPI mimetic. In order to quantitate the membrane integrated GPI mimetic after the exogenous addition to live cells, a tritium labelled cholesterol anchor was prepared. The radioactive label was introduced into the headgroup, and the radiolabelled GPI mimetic anchor was obtained with a specific activity of 1.37 TBq/mmol. The headgroup labelled cholesterol derivative was applied to demonstrate the sensitive detection of the cell membrane association of the anchor under in vivo conditions. Copyright © 2015 John Wiley & Sons, Ltd.

  12. Grasshopper Lazarillo, a GPI-anchored Lipocalin, increases Drosophila longevity and stress resistance, and functionally replaces its secreted homolog NLaz.

    Science.gov (United States)

    Ruiz, Mario; Wicker-Thomas, Claude; Sanchez, Diego; Ganfornina, Maria D

    2012-10-01

    Lazarillo (Laz) is a glycosyl-phosphatidylinositol (GPI)-linked glycoprotein first characterized in the developing nervous system of the grasshopper Schistocerca americana. It belongs to the Lipocalins, a functionally diverse family of mostly secreted proteins. In this work we test whether the protective capacity known for Laz homologs in flies and vertebrates (NLaz, GLaz and ApoD) is evolutionarily conserved in grasshopper Laz, and can be exerted from the plasma membrane in a cell-autonomous manner. First we demonstrate that extracellular forms of Laz have autocrine and paracrine protecting effects for oxidative stress-challenged Drosophila S2 cells. Then we assay the effects of overexpressing GPI-linked Laz in adult Drosophila and whether it rescues both known and novel phenotypes of NLaz null mutants. Local effects of GPI-linked Laz inside and outside the nervous system promote survival upon different stress forms, and extend lifespan and healthspan of the flies in a cell-type dependent manner. Outside the nervous system, expression in fat body cells but not in hemocytes results in protection. Within the nervous system, glial cell expression is more effective than neuronal expression. Laz actions are sexually dimorphic in some expression domains. Fat storage promotion and not modifications in hydrocarbon profiles or quantities explain the starvation-desiccation resistance caused by Laz overexpression. This effect is exerted when Laz is expressed ubiquitously or in dopaminergic cells, but not in hemocytes. Grasshopper Laz functionally restores the loss of NLaz, rescuing stress-sensitivity as well as premature accumulation of aging-related damage, monitored by advanced glycation end products (AGEs). However Laz does not rescue NLaz courtship behavioral defects. Finally, the presence of two new Lipocalins with predicted GPI-anchors in mosquitoes shows that the functional advantages of GPI-linkage have been commonly exploited by Lipocalins in the arthropodan lineage

  13. Glycosylphosphatidylinositol-Anchored Proteins in Fusarium graminearum: Inventory, Variability, and Virulence

    Science.gov (United States)

    Rittenour, William R.; Harris, Steven D.

    2013-01-01

    The contribution of cell surface proteins to plant pathogenicity of fungi is not well understood. As such, the objective of this study was to investigate the functions and importance of glycosylphosphatidylinositol-anchored proteins (GPI-APs) in the wheat pathogen F. graminearum. GPI-APs are surface proteins that are attached to either the membrane or cell wall. In order to simultaneously disrupt several GPI-APs, a phosphoethanolamine transferase-encoding gene gpi7 was deleted and the resultant mutant characterized in terms of growth, development, and virulence. The Δgpi7 mutants exhibited slower radial growth rates and aberrantly shaped macroconidia. Furthermore, virulence tests and microscopic analyses indicated that Gpi7 is required for ramification of the fungus throughout the rachis of wheat heads. In parallel, bioinformatics tools were utilized to predict and inventory GPI-APs within the proteome of F. graminearum. Two of the genes identified in this screen (FGSG_01588 and FGSG_08844) displayed isolate-specific length variability as observed for other fungal cell wall adhesion genes. Nevertheless, deletion of these genes failed to reveal obvious defects in growth, development, or virulence. This research demonstrates the global importance of GPI-APs to in planta proliferation in F. graminearum, and also highlights the potential of individual GPI-APs as diagnostic markers. PMID:24312325

  14. Deletion of Smgpi1 encoding a GPI-anchored protein suppresses sterility of the STRIPAK mutant ΔSmmob3 in the filamentous ascomycete Sordaria macrospora.

    Science.gov (United States)

    Frey, Stefan; Lahmann, Yasmine; Hartmann, Thomas; Seiler, Stephan; Pöggeler, Stefanie

    2015-08-01

    The striatin interacting phosphatase and kinase (STRIPAK) complex, which is composed of striatin, protein phosphatase PP2A and kinases, is required for fruiting-body development and cell fusion in the filamentous ascomycete Sordaria macrospora. Here, we report on the interplay of the glycosylphosphatidylinositol (GPI)-anchored protein SmGPI1 with the kinase activator SmMOB3, a core component of human and fungal STRIPAK complexes. SmGPI1 is conserved among filamentous ascomycetes and was first identified in a yeast two-hybrid screen using SmMOB3 as bait. The physical interaction of SmMOB3 and SmGPI1 was verified by co-immunoprecipitation. In vivo localization and differential centrifugation revealed that SmGPI1 is predominantly secreted and attached to the cell wall but is also associated with mitochondria and appears to be a dual-targeted protein. Deletion of Smgpi1 led to an increased number of fruiting bodies that were normally shaped but reduced in size. In addition, Smmob3 and Smgpi1 genetically interact. In the sterile ΔSmmob3 background deletion of Smgpi1 restores fertility, vegetative growth as well as hyphal-fusion defects. The suppression effect was specific for the ΔSmmob3 mutant as deletion of Smgpi1 in other STRIPAK mutants does not restore fertility. © 2015 John Wiley & Sons Ltd.

  15. COBRA encodes a putative GPI-anchored protein, which is polarly localized and necessary for oriented cell expansion in Arabidopsis.

    Science.gov (United States)

    Schindelman, G; Morikami, A; Jung, J; Baskin, T I; Carpita, N C; Derbyshire, P; McCann, M C; Benfey, P N

    2001-05-01

    To control organ shape, plant cells expand differentially. The organization of the cellulose microfibrils in the cell wall is a key determinant of differential expansion. Mutations in the COBRA (COB) gene of Arabidopsis, known to affect the orientation of cell expansion in the root, are reported here to reduce the amount of crystalline cellulose in cell walls in the root growth zone. The COB gene, identified by map-based cloning, contains a sequence motif found in proteins that are anchored to the extracellular surface of the plasma membrane through a glycosylphosphatidylinositol (GPI) linkage. In animal cells, this lipid linkage is known to confer polar localization to proteins. The COB protein was detected predominately on the longitudinal sides of root cells in the zone of rapid elongation. Moreover, COB RNA levels are dramatically upregulated in cells entering the zone of rapid elongation. Based on these results, models are proposed for the role of COB as a regulator of oriented cell expansion.

  16. Proteome analysis of Aspergillus fumigatus identifies glycosylphosphatidylinositol-anchored proteins associated to the cell wall biosynthesis.

    Science.gov (United States)

    Bruneau, J M; Magnin, T; Tagat, E; Legrand, R; Bernard, M; Diaquin, M; Fudali, C; Latgé, J P

    2001-08-01

    Previous studies in Aspergillus fumigatus (Mouyna I., Fontaine T., Vai M., Monod M., Fonzi W. A., Diaquin M., Popolo L., Hartland R. P., Latgé J.-P, J. Biol. Chem. 2000, 275, 14882-14889) have shown that a glucanosyltransferase playing an important role in fungal cell wall biosynthesis is glycosylphosphatidylinositol (GPI) anchored to the membrane. To identify other GPI-anchored proteins putatively involved in cell wall biogenesis, a proteomic analysis has been undertaken in A. fumigatus and the protein data were matched with the yeast genomic data. GPI-anchored proteins of A. fumigatus were released from membrane preparation by an endogenous GPI-phospholipase C, purified by liquid chromatography and separated by two-dimensional electrophoresis. They were characterized by their peptide mass fingerprint through matrix-assisted laser desorption/ionization-time of flight-(MALDI-TOF)-mass spectrometry and by internal amino acid sequencing. Nine GPI-anchored proteins were identified in A. fumigatus. Five of them were homologs of putatively GPI-anchored yeast proteins (Csa1p, Crh1p, Crh2p, Ecm33p, Gas1p) of unknown function but shown by gene disruption analysis to play a role in cell wall morphogenesis. In addition, a comparative study performed with chitin synthase and glucanosyl transferase mutants of A. fumigatus showed that a modification of the growth phenotype seen in these mutants was associated to an alteration of the pattern of GPI-anchored proteins. These results suggest that GPI-anchored proteins identified in this study are involved in A. fumigatus cell wall organization.

  17. Screening for Glycosylphosphatidylinositol-Modified Cell Wall Proteins in Pichia pastoris and Their Recombinant Expression on the Cell Surface

    Science.gov (United States)

    Zhang, Li; Liang, Shuli; Zhou, Xinying; Jin, Zi; Jiang, Fengchun; Han, Shuangyan; Zheng, Suiping

    2013-01-01

    Glycosylphosphatidylinositol (GPI)-anchored glycoproteins have various intrinsic functions in yeasts and different uses in vitro. In the present study, the genome of Pichia pastoris GS115 was screened for potential GPI-modified cell wall proteins. Fifty putative GPI-anchored proteins were selected on the basis of (i) the presence of a C-terminal GPI attachment signal sequence, (ii) the presence of an N-terminal signal sequence for secretion, and (iii) the absence of transmembrane domains in mature protein. The predicted GPI-anchored proteins were fused to an alpha-factor secretion signal as a substitute for their own N-terminal signal peptides and tagged with the chimeric reporters FLAG tag and mature Candida antarctica lipase B (CALB). The expression of fusion proteins on the cell surface of P. pastoris GS115 was determined by whole-cell flow cytometry and immunoblotting analysis of the cell wall extracts obtained by β-1,3-glucanase digestion. CALB displayed on the cell surface of P. pastoris GS115 with the predicted GPI-anchored proteins was examined on the basis of potential hydrolysis of p-nitrophenyl butyrate. Finally, 13 proteins were confirmed to be GPI-modified cell wall proteins in P. pastoris GS115, which can be used to display heterologous proteins on the yeast cell surface. PMID:23835174

  18. Complementation of essential yeast GPI mannosyltransferase mutations suggests a novel specificity for certain Trypanosoma and Plasmodium PigB proteins.

    Directory of Open Access Journals (Sweden)

    Leslie K Cortes

    Full Text Available The glycosylphosphatidylinositol (GPI anchor is an essential glycolipid that tethers certain eukaryotic proteins to the cell surface. The core structure of the GPI anchor is remarkably well conserved across evolution and consists of NH2-CH2-CH2-PO4-6Manα1,2Manα1,6Manα1,4-GlcNα1,6-myo-inositol-PO4-lipid. The glycan portion of this structure may be modified with various side-branching sugars or other compounds that are heterogeneous and differ from organism to organism. One such modification is an α(1,2-linked fourth mannose (Man-IV that is side-branched to the third mannose (Man-III of the trimannosyl core. In fungi and mammals, addition of Man-III and Man-IV occurs by two distinct Family 22 α(1,2-mannosyltransferases, Gpi10/PigB and Smp3/PigZ, respectively. However, in the five protozoan parasite genomes we examined, no genes encoding Smp3/PigZ proteins were observed, despite reports of tetramannosyl-GPI structures (Man4-GPIs being produced by some parasites. In this study, we tested the hypothesis that the Gpi10/PigB proteins produced by protozoan parasites have the ability to add both Man-III and Man-IV to GPI precursors. We used yeast genetics to test the in vivo specificity of Gpi10/PigB proteins from several Plasmodium and Trypanosoma species by examining their ability to restore viability to Saccharomyces cerevisiae strains harboring lethal defects in Man-III (gpi10Δ or Man-IV (smp3Δ addition to GPI precursor lipids. We demonstrate that genes encoding PigB enzymes from T. cruzi, T. congolense and P. falciparum are each capable of separately complementing essential gpi10Δ and smp3Δ mutations, while PIGB genes from T. vivax and T. brucei only complement gpi10Δ. Additionally, we show the ability of T. cruzi PIGB to robustly complement a gpi10Δ/smp3Δ double mutant. Our data suggest that certain Plasmodium and Trypanosoma PigB mannosyltransferases can transfer more than one mannose to GPI precursors in vivo, and suggest a novel

  19. Glycosylphosphatidylinositol-anchored proteins are required for cell wall synthesis and morphogenesis in Arabidopsis.

    Science.gov (United States)

    Gillmor, C Stewart; Lukowitz, Wolfgang; Brininstool, Ginger; Sedbrook, John C; Hamann, Thorsten; Poindexter, Patricia; Somerville, Chris

    2005-04-01

    Mutations at five loci named PEANUT1-5 (PNT) were identified in a genetic screen for radially swollen embryo mutants. pnt1 cell walls showed decreased crystalline cellulose, increased pectins, and irregular and ectopic deposition of pectins, xyloglucans, and callose. Furthermore, pnt1 pollen is less viable than the wild type, and pnt1 embryos were delayed in morphogenesis and showed defects in shoot and root meristems. The PNT1 gene encodes the Arabidopsis thaliana homolog of mammalian PIG-M, an endoplasmic reticulum-localized mannosyltransferase that is required for synthesis of the glycosylphosphatidylinositol (GPI) anchor. All five pnt mutants showed strongly reduced accumulation of GPI-anchored proteins, suggesting that they all have defects in GPI anchor synthesis. Although the mutants are seedling lethal, pnt1 cells are able to proliferate for a limited time as undifferentiated callus and do not show the massive deposition of ectopic cell wall material seen in pnt1 embryos. The different phenotype of pnt1 cells in embryos and callus suggest a differential requirement for GPI-anchored proteins in cell wall synthesis in these two tissues and points to the importance of GPI anchoring in coordinated multicellular growth.

  20. Glycosylphosphatidylinositol Anchor Modification Machinery Deficiency Is Responsible for the Formation of Pro-Prion Protein (PrP) in BxPC-3 Protein and Increases Cancer Cell Motility*

    Science.gov (United States)

    Yang, Liheng; Gao, Zhenxing; Hu, Lipeng; Wu, Guiru; Yang, Xiaowen; Zhang, Lihua; Zhu, Ying; Wong, Boon-Seng; Xin, Wei; Sy, Man-Sun; Li, Chaoyang

    2016-01-01

    The normal cellular prion protein (PrP) is a glycosylphosphatidylinositol (GPI)-anchored cell surface glycoprotein. However, in pancreatic ductal adenocarcinoma cell lines, such as BxPC-3, PrP exists as a pro-PrP retaining its glycosylphosphatidylinositol (GPI) peptide signaling sequence. Here, we report the identification of another pancreatic ductal adenocarcinoma cell line, AsPC-1, which expresses a mature GPI-anchored PrP. Comparison of the 24 genes involved in the GPI anchor modification pathway between AsPC-1 and BxPC-3 revealed 15 of the 24 genes, including PGAP1 and PIG-F, were down-regulated in the latter cells. We also identified six missense mutations in DPM2, PIG-C, PIG-N, and PIG-P alongside eight silent mutations. When BxPC-3 cells were fused with Chinese hamster ovary (CHO) cells, which lack endogenous PrP, pro-PrP was successfully converted into mature GPI-anchored PrP. Expression of the individual gene, such as PGAP1, PIG-F, or PIG-C, into BxPC-3 cells does not result in phosphoinositide-specific phospholipase C sensitivity of PrP. However, when PIG-F but not PIG-P is expressed in PGAP1-expressing BxPC-3 cells, PrP on the surface of the cells becomes phosphoinositide-specific phospholipase C-sensitive. Thus, low expression of PIG-F and PGAP1 is the major factor contributing to the accumulation of pro-PrP. More importantly, BxPC-3 cells expressing GPI-anchored PrP migrate much slower than BxPC-3 cells bearing pro-PrP. In addition, GPI-anchored PrP-bearing AsPC-1 cells also migrate slower than pro-PrP bearing BxPC-3 cells, although both cells express filamin A. “Knocking out” PRNP in BxPC-3 cell drastically reduces its migration. Collectively, these results show that multiple gene irregularity in BxPC-3 cells is responsible for the formation of pro-PrP, and binding of pro-PrP to filamin A contributes to enhanced tumor cell motility. PMID:26683373

  1. Characterization of sialylated and fucosylated glycopeptides of beta2-glycoprotein I by a combination of HILIC LC and MALDI MS/MS

    DEFF Research Database (Denmark)

    Kondo, Akira; Thaysen-Andersen, Morten; Hjernø, Karin

    2010-01-01

    were characterized using MALDI quadrupole TOF MS/MS. A total of 23 glycan structures, including sialylated bi- and tri-antennary complex type glycans, were characterized at three N-glycosylation sites, namely Asn-143, Asn-174 and Asn-234, of beta2-GPI. Further exploration of the complementary nature...

  2. Glycosylphosphatidylinositol Anchor Modification Machinery Deficiency Is Responsible for the Formation of Pro-Prion Protein (PrP) in BxPC-3 Protein and Increases Cancer Cell Motility.

    Science.gov (United States)

    Yang, Liheng; Gao, Zhenxing; Hu, Lipeng; Wu, Guiru; Yang, Xiaowen; Zhang, Lihua; Zhu, Ying; Wong, Boon-Seng; Xin, Wei; Sy, Man-Sun; Li, Chaoyang

    2016-02-19

    The normal cellular prion protein (PrP) is a glycosylphosphatidylinositol (GPI)-anchored cell surface glycoprotein. However, in pancreatic ductal adenocarcinoma cell lines, such as BxPC-3, PrP exists as a pro-PrP retaining its glycosylphosphatidylinositol (GPI) peptide signaling sequence. Here, we report the identification of another pancreatic ductal adenocarcinoma cell line, AsPC-1, which expresses a mature GPI-anchored PrP. Comparison of the 24 genes involved in the GPI anchor modification pathway between AsPC-1 and BxPC-3 revealed 15 of the 24 genes, including PGAP1 and PIG-F, were down-regulated in the latter cells. We also identified six missense mutations in DPM2, PIG-C, PIG-N, and PIG-P alongside eight silent mutations. When BxPC-3 cells were fused with Chinese hamster ovary (CHO) cells, which lack endogenous PrP, pro-PrP was successfully converted into mature GPI-anchored PrP. Expression of the individual gene, such as PGAP1, PIG-F, or PIG-C, into BxPC-3 cells does not result in phosphoinositide-specific phospholipase C sensitivity of PrP. However, when PIG-F but not PIG-P is expressed in PGAP1-expressing BxPC-3 cells, PrP on the surface of the cells becomes phosphoinositide-specific phospholipase C-sensitive. Thus, low expression of PIG-F and PGAP1 is the major factor contributing to the accumulation of pro-PrP. More importantly, BxPC-3 cells expressing GPI-anchored PrP migrate much slower than BxPC-3 cells bearing pro-PrP. In addition, GPI-anchored PrP-bearing AsPC-1 cells also migrate slower than pro-PrP bearing BxPC-3 cells, although both cells express filamin A. "Knocking out" PRNP in BxPC-3 cell drastically reduces its migration. Collectively, these results show that multiple gene irregularity in BxPC-3 cells is responsible for the formation of pro-PrP, and binding of pro-PrP to filamin A contributes to enhanced tumor cell motility. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

  3. A glycosylphosphatidylinositol anchor is required for membrane localization but dispensable for cell wall association of chitin deacetylase 2 in Cryptococcus neoformans.

    Science.gov (United States)

    Gilbert, Nicole M; Baker, Lorina G; Specht, Charles A; Lodge, Jennifer K

    2012-01-01

    Cell wall proteins (CWPs) mediate important cellular processes in fungi, including adhesion, invasion, biofilm formation, and flocculation. The current model of fungal cell wall organization includes a major class of CWPs covalently bound to β-1,6-glucan via a remnant of a glycosylphosphatidylinositol (GPI) anchor. This model was established by studies of ascomycetes more than a decade ago, and relatively little work has been done with other fungi, although the presumption has been that proteins identified in the cell wall which contain a predicted GPI anchor are covalently linked to cell wall glucans. The pathogenic basidiomycete Cryptococcus neoformans encodes >50 putatively GPI-anchored proteins, some of which have been identified in the cell wall. One of these proteins is chitin deacetylase 2 (Cda2), an enzyme responsible for converting chitin to chitosan, a cell wall polymer recently established as a virulence factor for C. neoformans infection of mammalian hosts. Using a combination of biochemistry, molecular biology, and genetics, we show that Cda2 is GPI anchored to membranes but noncovalently associated with the cell wall by means independent of both its GPI anchor and β-1,6-glucan. We also show that Cda2 produces chitosan when localized to the plasma membrane, but association with the cell wall is not essential for this process, thereby providing insight into the mechanism of chitosan biosynthesis. These results increase our understanding of the surface of C. neoformans and provide models of cell walls likely applicable to other undercharacterized basidiomycete pathogenic fungi. The surface of a pathogenic microbe is a major interface with its host. In fungi, the outer surface consists of a complex matrix known as the cell wall, which includes polysaccharides, proteins, and other molecules. The mammalian host recognizes many of these surface molecules and mounts appropriate responses to combat the microbial infection. Cryptococcus neoformans is a

  4. N-Glycosylation instead of cholesterol mediates oligomerization and apical sorting of GPI-APs in FRT cells.

    Science.gov (United States)

    Imjeti, Naga Salaija; Lebreton, Stéphanie; Paladino, Simona; de la Fuente, Erwin; Gonzalez, Alfonso; Zurzolo, Chiara

    2011-12-01

    Sorting of glycosylphosphatidyl-inositol--anchored proteins (GPI-APs) in polarized epithelial cells is not fully understood. Oligomerization in the Golgi complex has emerged as the crucial event driving apical segregation of GPI-APs in two different kind of epithelial cells, Madin-Darby canine kidney (MDCK) and Fisher rat thyroid (FRT) cells, but whether the mechanism is conserved is unknown. In MDCK cells cholesterol promotes GPI-AP oligomerization, as well as apical sorting of GPI-APs. Here we show that FRT cells lack this cholesterol-driven oligomerization as apical sorting mechanism. In these cells both apical and basolateral GPI-APs display restricted diffusion in the Golgi likely due to a cholesterol-enriched membrane environment. It is striking that N-glycosylation is the critical event for oligomerization and apical sorting of GPI-APs in FRT cells but not in MDCK cells. Our data indicate that at least two mechanisms exist to determine oligomerization in the Golgi leading to apical sorting of GPI-APs. One depends on cholesterol, and the other depends on N-glycosylation and is insensitive to cholesterol addition or depletion.

  5. BcCFEM1, a CFEM Domain-Containing Protein with Putative GPI-Anchored Site, Is Involved in Pathogenicity, Conidial Production, and Stress Tolerance in Botrytis cinerea

    Directory of Open Access Journals (Sweden)

    Wenjun Zhu

    2017-09-01

    Full Text Available We experimentally isolated and characterized a CFEM protein with putative GPI-anchored site BcCFEM1 in Botrytis cinerea. BcCFEM1 contains a CFEM (common in several fungal extracellular membrane proteins domain with the characteristic eight cysteine residues at N terminus, and a predicted GPI modification site at C terminus. BcCFEM1 was significantly up-regulated during early stage of infection on bean leaves and induced chlorosis in Nicotiana benthamiana leaves using Agrobacterium infiltration method. Targeted deletion of BcCFEM1 in B. cinerea affected virulence, conidial production and stress tolerance, but not growth rate, conidial germination, colony morphology, and sclerotial formation. However, over expression of BcCFEM1 did not make any observable phenotype change. Therefore, our data suggested that BcCFEM1 contributes to virulence, conidial production, and stress tolerance. These findings further enhance our understanding on the sophisticated pathogenicity of B. cinerea beyond necrotrophic stage, highlighting the importance of CFEM protein to B. cinerea and other broad-host-range necrotrophic pathogens.

  6. Plasmodium falciparum merozoite surface protein 1 - Glycosylation and localization to low-density, detergent-resistant membranes in the parasitized erythrocyte

    DEFF Research Database (Denmark)

    Hoessli, D.C.; Poincelet, M.; Gupta, Ramneek

    2003-01-01

    In addition to the major carbohydrate moieties of the glycosylphosphatidylinositol (GPI) anchor, we report that Plasmodium falciparum merozoite surface protein 1 (MSP-1) bears O-GlcNAc modifications predominantly in beta-anomeric configuration, in both the C- and N-terminal portions of the protein....... Subcellular fractionation of parasitized erythrocytes in the late trophozoite/schizont stage reveals that GPI-anchored C-terminal fragments of MSP-1 are recovered in Triton X-100 resistant, low-density membrane fractions. Our results suggest that O -GlcNAc-modified MSP-1 N-terminal fragments tend to localize...... within the parasitophorous vacuolar membrane while GPI-anchored MSP-1 C-terminal fragments associate with low-density, Triton X-100 resistant membrane domains (rafts), redistribute in the parasitized erythrocyte and are eventually shed as membrane vesicles that also contain the endogenous, GPI-linked CD...

  7. The Glycosylphosphatidylinositol-Anchored Variable Region of Llama Heavy Chain-Only Antibody JM4 Efficiently Blocks both Cell-Free and T Cell-T Cell Transmission of Human Immunodeficiency Virus Type 1.

    Science.gov (United States)

    Liu, Lihong; Wang, Weiming; Matz, Julie; Ye, Chaobaihui; Bracq, Lucie; Delon, Jerome; Kimata, Jason T; Chen, Zhiwei; Benichou, Serge; Zhou, Paul

    2016-12-01

    The variable regions (VHHs) of two heavy chain-only antibodies, JM2 and JM4, from llamas that have been immunized with a trimeric gp140 bound to a CD4 mimic have been recently isolated (here referred to as VHH JM2 and VHH JM4, respectively). JM2 binds the CD4-binding site of gp120 and neutralizes HIV-1 strains from subtypes B, C, and G. JM4 binds gp120 and neutralizes HIV-1 strains from subtypes A, B, C, A/E, and G in a CD4-dependent manner. In the present study, we constructed glycosylphosphatidylinositol (GPI)-anchored VHH JM2 and JM4 along with an E4 control and transduced them into human CD4 + cell lines and primary CD4 T cells. We report that by genetically linking the VHHs with a GPI attachment signal, VHHs are targeted to the lipid rafts of the plasma membranes. Expression of GPI-VHH JM4, but not GPI-VHH E4 and JM2, on the surface of transduced TZM.bl cells potently neutralizes multiple subtypes of HIV-1 isolates, including tier 2 or 3 strains, transmitted founders, quasispecies, and soluble single domain antibody (sdAb) JM4-resistant viruses. Moreover, transduction of CEMss-CCR5 cells with GPI-VHH JM4, but not with GPI-VHH E4, confers resistance to both cell-free and T cell-T cell transmission of HIV-1 and HIV-1 envelope-mediated fusion. Finally, GPI-VHH JM4-transduced human primary CD4 T cells efficiently resist both cell-free and T cell-T cell transmission of HIV-1. Thus, we conclude that VHH JM4, when targeted to the lipid rafts of the plasma membrane, efficiently neutralizes HIV-1 infection via both cell-free and T cell-T cell transmission. Our findings should have important implications for GPI-anchored antibody-based therapy against HIV-1. Lipid rafts are specialized dynamic microdomains of the plasma membrane and have been shown to be gateways for HIV-1 budding as well as entry into T cells and macrophages. In nature, many glycosylphosphatidylinositol (GPI)-anchored proteins localize in the lipid rafts. In the present study, we developed GPI-anchored

  8. The GPI-anchored protein Ecm33 is vital for conidiation, cell wall integrity, and multi-stress tolerance of two filamentous entomopathogens but not for virulence.

    Science.gov (United States)

    Chen, Ying; Zhu, Jing; Ying, Sheng-Hua; Feng, Ming-Guang

    2014-06-01

    Ecm33 is one of several glycosylphosphatidylinositol (GPI)-anchored proteins. This protein is known to be involved in fungal cell wall integrity, but its contribution to multi-stress tolerance is largely unknown. Here we characterized the functions of two Ecm33 orthologues, i.e., Bbecm33 in Beauveria bassiana and Mrecm33 in Metarhizium robertsii. Bbecm33 and Mrecm33 were both confirmed as GPI-anchored cell wall proteins in immunogold localization. Single-gene disruptions of Bbecm33 and Mrecm33 caused slight growth defects, but conidial yield decreased much more in ΔBbecm33 (76 %) than in ΔMrecm33 (42 %), accompanied with significant reductions of intracellular mannitol and trehalose contents in both mutants and weakened cell walls in ΔBbecm33 only. Consequently, ΔBbecm33 was far more sensitive to the cell wall-perturbating agents Congo red and sodium dodecyl sulfate (SDS) than ΔMrecm33, which showed null response to SDS. Both deletion mutants became significantly more sensitive to two oxidants (menadione and H2O2), two fungicides (carbendazim and ethirimol), osmotic salt NaCl, and Ca(2+) during growth despite some degrees of differences in their sensitivities to the chemical stressors. Strikingly, conidial UV-B resistance decreased by 55 % in ΔBbecm33 but was unaffected in ΔMrecm33, unlike a similar decrease (25-28 %) of conidial thermotolerance in both. All the changes were restored to wild-type levels by gene complementation through ectopic gene integration in each fungus. However, neither ΔBbecm33 nor ΔMrecm33 showed a significant change in virulence to a susceptible insect host. Our results indicate that Bbecm33 and Mrecm33 contribute differentially to the conidiation and multi-stress tolerance of B. bassiana and M. robertsii.

  9. Induction of IL-12 Production in Human Peripheral Monocytes by Trypanosoma cruzi Is Mediated by Glycosylphosphatidylinositol-Anchored Mucin-Like Glycoproteins and Potentiated by IFN-γ and CD40-CD40L Interactions

    Directory of Open Access Journals (Sweden)

    Lúcia Cristina Jamli Abel

    2014-01-01

    Full Text Available Chagas disease, caused by the protozoan parasite Trypanosoma cruzi (T. cruzi, is characterized by immunopathology driven by IFN-γ secreting Th1-like T cells. T. cruzi has a thick coat of mucin-like glycoproteins covering its surface, which plays an important role in parasite invasion and host immunomodulation. It has been extensively described that T. cruzi or its products—like GPI anchors isolated from GPI-anchored mucins from the trypomastigote life cycle stage (tGPI-mucins—are potent inducers of proinflammatory responses (i.e., cytokines and NO production by IFN-γ primed murine macrophages. However, little is known about whether T. cruzi or GPI-mucins exert a similar action in human cells. We therefore decided to further investigate the in vitro cytokine production profile from human mononuclear cells from uninfected donors exposed to T. cruzi as well as tGPI-mucins. We observed that both living T. cruzi trypomastigotes and tGPI-mucins are potent inducers of IL-12 by human peripheral blood monocytes and this effect depends on CD40-CD40L interaction and IFN-γ. Our findings suggest that the polarized T1-type cytokine profile seen in T. cruzi infected patients might be a long-term effect of IL-12 production induced by lifelong exposure to T. cruzi tGPI-mucins.

  10. Expression of membrane anchored cytokines and B7-1 alters tumor microenvironment and induces protective antitumor immunity in a murine breast cancer model.

    Science.gov (United States)

    Bozeman, Erica N; Cimino-Mathews, Ashley; Machiah, Deepa K; Patel, Jaina M; Krishnamoorthy, Arun; Tien, Linda; Shashidharamurthy, Rangaiah; Selvaraj, Periasamy

    2013-05-07

    Many studies have shown that the systemic administration of cytokines or vaccination with cytokine-secreting tumors augments an antitumor immune response that can result in eradication of tumors. However, these approaches are hampered by the risk of systemic toxicity induced by soluble cytokines. In this study, we have evaluated the efficacy of 4TO7, a highly tumorigenic murine mammary tumor cell line, expressing glycosyl phosphatidylinositol (GPI)-anchored form of cytokine molecules alone or in combination with the costimulatory molecule B7-1 as a model for potential cell or membrane-based breast cancer vaccines. We observed that the GPI-anchored cytokines expressed on the surface of tumor cells greatly reduced the overall tumorigenicity of the 4TO7 tumor cells following direct live cell challenge as evidenced by transient tumor growth and complete regression within 30 days post challenge. Tumors co-expressing B7-1 and GPI-IL-12 grew the least and for the shortest duration, suggesting that this combination of immunostimulatory molecules is most potent. Protective immune responses were also observed following secondary tumor challenge. Further, the 4TO7-B7-1/GPI-IL-2 and 4TO7-B7-1/GPI-IL-12 transfectants were capable of inducing regression of a wild-type tumor growing at a distant site in a concomitant tumor challenge model, suggesting the tumor immunity elicited by the transfectants can act systemically and inhibit the tumor growth at a distant site. Additionally, when used as irradiated whole cell vaccines, 4TO7-B7-1/GPI-IL-12 led to a significant inhibition in tumor growth of day 7 established tumors. Lastly, we observed a significant decrease in the prevalence of myeloid-derived suppressor cells and regulatory T-cells in the tumor microenvironment on day 7 post challenge with 4TO7-B7-1/GPI-IL-12 cells, which provides mechanistic insight into antitumor efficacy of the tumor-cell membrane expressed IL-12. These studies have implications in designing membrane

  11. Awa1p on the cell surface of sake yeast inhibits biofilm formation and the co-aggregation between sake yeasts and Lactobacillus plantarum ML11-11.

    Science.gov (United States)

    Hirayama, Satoru; Shimizu, Masashi; Tsuchiya, Noriko; Furukawa, Soichi; Watanabe, Daisuke; Shimoi, Hitoshi; Takagi, Hiroshi; Ogihara, Hirokazu; Morinaga, Yasushi

    2015-05-01

    We examined mixed-species biofilm formation between Lactobacillus plantarum ML11-11 and both foaming and non-foaming mutant strains of Saccharomyces cerevisiae sake yeasts. Wild-type strains showed significantly lower levels of biofilm formation compared with the non-foaming mutants. Awa1p, a protein involved in foam formation during sake brewing, is a glycosylphosphatidylinositol (GPI)-anchored protein and is associated with the cell wall of sake yeasts. The AWA1 gene of the non-foaming mutant strain Kyokai no. 701 (K701) has lost the C-terminal sequence that includes the GPI anchor signal. Mixed-species biofilm formation and co-aggregation of wild-type strain Kyokai no. 7 (K7) were significantly lower than K701 UT-1 (K701 ura3/ura3 trp1/trp1), while the levels of strain K701 UT-1 carrying the AWA1 on a plasmid were comparable to those of K7. The levels of biofilm formation and co-aggregation of the strain K701 UT-1 harboring AWA1 with a deleted GPI anchor signal were similar to those of K701 UT-1. These results clearly demonstrate that Awa1p present on the surface of sake yeast strain K7 inhibits adhesion between yeast cells and L. plantarum ML11-11, consequently impeding mixed-species biofilm formation. Copyright © 2014 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

  12. Sialylation regulates myofibroblast differentiation of human skin fibroblasts.

    Science.gov (United States)

    Sasaki, Norihiko; Itakura, Yoko; Toyoda, Masashi

    2017-04-18

    Fibroblasts are key players in maintaining skin homeostasis and in orchestrating physiological tissue repair and skin regeneration. Dysfunctions in fibroblasts that occur with aging and the senescent process lead to the delayed healing observed in elderly people. The molecular mechanisms leading to fibroblast dysfunction during aging and the senescent process have not yet been clarified. Previously, changes in patterns of glycosylation were observed in fibroblasts in aging and the senescent process, but the effect of these changes on the function of fibroblasts has not been well documented. Here, we investigated whether changes in glycosylation during the process to senescence may have functional effects on fibroblasts. The changes in cell surface glycans on skin fibroblasts during the process to senescence were examined in early-passage (EP) and late-passage (LP) skin fibroblasts by fluorescence-activated cell sorting analysis using lectins. The contributors to the changes in cell surface glycans were examined by real-time polymerase chain reaction or Western blot analysis. The effects of changes in glycosylation on proliferation, migration, induction of cellular senescence, and myofibroblast differentiation induced by transforming growth factor (TGF)-β1 stimulation were examined in EP fibroblasts. The changes in glycosylation were performed by GalNAc-α-O-benzyl or sialidase treatment. A decrease in sialylation of glycoproteins and an increase in sialidase NEU1 were observed in LP fibroblasts. The reduction of sialylation did not have any effect on proliferation, migration, or induction of cellular senescence. On the other hand, myofibroblast differentiation was inhibited by the reduction of sialylation, indicating that sialylation is important for myofibroblast differentiation. The localization of CD44 in lipid rafts, which is required for myofibroblast differentiation, was inhibited by the reduction of sialylation. Furthermore, reduced myofibroblast

  13. A novel dimeric inhibitor targeting Beta2GPI in Beta2GPI/antibody complexes implicated in antiphospholipid syndrome.

    Directory of Open Access Journals (Sweden)

    Alexey Kolyada

    2010-12-01

    Full Text Available β2GPI is a major antigen for autoantibodies associated with antiphospholipid syndrome (APS, an autoimmune disease characterized by thrombosis and recurrent pregnancy loss. Only the dimeric form of β2GPI generated by anti-β2GPI antibodies is pathologically important, in contrast to monomeric β2GPI which is abundant in plasma.We created a dimeric inhibitor, A1-A1, to selectively target β2GPI in β2GPI/antibody complexes. To make this inhibitor, we isolated the first ligand-binding module from ApoER2 (A1 and connected two A1 modules with a flexible linker. A1-A1 interferes with two pathologically important interactions in APS, the binding of β2GPI/antibody complexes with anionic phospholipids and ApoER2. We compared the efficiency of A1-A1 to monomeric A1 for inhibition of the binding of β2GPI/antibody complexes to anionic phospholipids. We tested the inhibition of β2GPI present in human serum, β2GPI purified from human plasma and the individual domain V of β2GPI. We demonstrated that when β2GPI/antibody complexes are formed, A1-A1 is much more effective than A1 in inhibition of the binding of β2GPI to cardiolipin, regardless of the source of β2GPI. Similarly, A1-A1 strongly inhibits the binding of dimerized domain V of β2GPI to cardiolipin compared to the monomeric A1 inhibitor. In the absence of anti-β2GPI antibodies, both A1-A1 and A1 only weakly inhibit the binding of pathologically inactive monomeric β2GPI to cardiolipin.Our results suggest that the approach of using a dimeric inhibitor to block β2GPI in the pathological multivalent β2GPI/antibody complexes holds significant promise. The novel inhibitor A1-A1 may be a starting point in the development of an effective therapeutic for antiphospholipid syndrome.

  14. A Novel Dimeric Inhibitor Targeting Beta2GPI in Beta2GPI/Antibody Complexes Implicated in Antiphospholipid Syndrome

    Energy Technology Data Exchange (ETDEWEB)

    A Kolyada; C Lee; A De Biasio; N Beglova

    2011-12-31

    {beta}2GPI is a major antigen for autoantibodies associated with antiphospholipid syndrome (APS), an autoimmune disease characterized by thrombosis and recurrent pregnancy loss. Only the dimeric form of {beta}2GPI generated by anti-{beta}2GPI antibodies is pathologically important, in contrast to monomeric {beta}2GPI which is abundant in plasma. We created a dimeric inhibitor, A1-A1, to selectively target {beta}2GPI in {beta}2GPI/antibody complexes. To make this inhibitor, we isolated the first ligand-binding module from ApoER2 (A1) and connected two A1 modules with a flexible linker. A1-A1 interferes with two pathologically important interactions in APS, the binding of {beta}2GPI/antibody complexes with anionic phospholipids and ApoER2. We compared the efficiency of A1-A1 to monomeric A1 for inhibition of the binding of {beta}2GPI/antibody complexes to anionic phospholipids. We tested the inhibition of {beta}2GPI present in human serum, {beta}2GPI purified from human plasma and the individual domain V of {beta}2GPI. We demonstrated that when {beta}2GPI/antibody complexes are formed, A1-A1 is much more effective than A1 in inhibition of the binding of {beta}2GPI to cardiolipin, regardless of the source of {beta}2GPI. Similarly, A1-A1 strongly inhibits the binding of dimerized domain V of {beta}2GPI to cardiolipin compared to the monomeric A1 inhibitor. In the absence of anti-{beta}2GPI antibodies, both A1-A1 and A1 only weakly inhibit the binding of pathologically inactive monomeric {beta}2GPI to cardiolipin. Our results suggest that the approach of using a dimeric inhibitor to block {beta}2GPI in the pathological multivalent {beta}2GPI/antibody complexes holds significant promise. The novel inhibitor A1-A1 may be a starting point in the development of an effective therapeutic for antiphospholipid syndrome.

  15. Chemo-enzymatic synthesis of Neu5Gc-containing sialylated lactulose

    African Journals Online (AJOL)

    The sialic acid modification on cell surface glycoproteins and glycolipids plays a crucial role in many biological processes, including cell adhesion, antigen recognition and signal transduction [17]. Studies have shown that sialylated glycans have a good prospect in food, especially the developing nervous system in.

  16. Expression and Purification of Glycosyltransferases in Pichia Pastoris: Towards Improving the Migration of Stem Cells by Enhancing Surface Expression of Sialyl Lewis X

    KAUST Repository

    Al-Amoodi, Asma S.

    2017-05-01

    Recruitment of circulating cells towards target sites is primarily dependent on E-selectin receptor/ligand adhesive interactions. Glycosyltransferase (GTs) are involved in the creation of E-selectin ligands. A sialofucosylated terminal tetrasaccharide like glycan structure known as sialyl Lewis x (sLex), is the most recognized ligand by selectins. This structure is found on the surface of cancer cells and leukocytes but is often absent on the surface of many adult stem cell populations. In order to synthesize sLex, GTs must be endogenously expressed and remain active within the cells. Generally, these stem cells express terminal sialylated lactosamine structures on their glycoproteins which require the addition of alpha-(1,3)-fucose to be converted into an E-selectin ligand. There are a number of fucosyltransferases (FUTs) that are able to modify terminal lactosamine structures to create sLex such as FUT6. In this work we focused on expressing and purifying active recombinant FUTs as a tool to help create sLex structures on the surface of adult stem cells in order to enhance their migration.

  17. Plasmodium falciparum merozoite surface protein 1 - Glycosylation and localization to low-density, detergent-resistant membranes in the parasitized erythrocyte

    DEFF Research Database (Denmark)

    Hoessli, D.C.; Poincelet, M.; Gupta, Ramneek

    2003-01-01

    In addition to the major carbohydrate moieties of the glycosylphosphatidylinositol (GPI) anchor, we report that Plasmodium falciparum merozoite surface protein 1 (MSP-1) bears O-GlcNAc modifications predominantly in beta-anomeric configuration, in both the C- and N-terminal portions of the protei...

  18. Immunogenic Eimeria tenella glycosylphosphatidylinositol-anchored surface antigens (SAGs induce inflammatory responses in avian macrophages.

    Directory of Open Access Journals (Sweden)

    Yock-Ping Chow

    Full Text Available At least 19 glycosylphosphatidylinositol (GPI-anchored surface antigens (SAGs are expressed specifically by second-generation merozoites of Eimeria tenella, but the ability of these proteins to stimulate immune responses in the chicken is unknown.Ten SAGs, belonging to two previously defined multigene families (A and B, were expressed as soluble recombinant (r fusion proteins in E. coli. Chicken macrophages were treated with purified rSAGs and changes in macrophage nitrite production, and in mRNA expression profiles of inducible nitric oxide synthase (iNOS and of a panel of cytokines were measured. Treatment with rSAGs 4, 5, and 12 induced high levels of macrophage nitric oxide production and IL-1β mRNA transcription that may contribute to the inflammatory response observed during E. tenella infection. Concomitantly, treatment with rSAGs 4, 5 and 12 suppressed the expression of IL-12 and IFN-γ and elevated that of IL-10, suggesting that during infection these molecules may specifically impair the development of cellular mediated immunity.In summary, some E. tenella SAGs appear to differentially modulate chicken innate and humoral immune responses and those derived from multigene family A (especially rSAG 12 may be more strongly linked with E. tenella pathogenicity associated with the endogenous second generation stages.

  19. Dynamic partitioning of a glycosyl-phosphatidylinositol-anchored protein in glycosphingolipid-rich microdomains imaged by single-quantum dot tracking.

    Science.gov (United States)

    Pinaud, Fabien; Michalet, Xavier; Iyer, Gopal; Margeat, Emmanuel; Moore, Hsiao-Ping; Weiss, Shimon

    2009-06-01

    Recent experimental developments have led to a revision of the classical fluid mosaic model proposed by Singer and Nicholson more than 35 years ago. In particular, it is now well established that lipids and proteins diffuse heterogeneously in cell plasma membranes. Their complex motion patterns reflect the dynamic structure and composition of the membrane itself, as well as the presence of the underlying cytoskeleton scaffold and that of the extracellular matrix. How the structural organization of plasma membranes influences the diffusion of individual proteins remains a challenging, yet central, question for cell signaling and its regulation. Here we have developed a raft-associated glycosyl-phosphatidyl-inositol-anchored avidin test probe (Av-GPI), whose diffusion patterns indirectly report on the structure and dynamics of putative raft microdomains in the membrane of HeLa cells. Labeling with quantum dots (qdots) allowed high-resolution and long-term tracking of individual Av-GPI and the classification of their various diffusive behaviors. Using dual-color total internal reflection fluorescence (TIRF) microscopy, we studied the correlation between the diffusion of individual Av-GPI and the location of glycosphingolipid GM1-rich microdomains and caveolae. We show that Av-GPI exhibit a fast and a slow diffusion regime in different membrane regions, and that slowing down of their diffusion is correlated with entry in GM1-rich microdomains located in close proximity to, but distinct, from caveolae. We further show that Av-GPI dynamically partition in and out of these microdomains in a cholesterol-dependent manner. Our results provide direct evidence that cholesterol-/sphingolipid-rich microdomains can compartmentalize the diffusion of GPI-anchored proteins in living cells and that the dynamic partitioning raft model appropriately describes the diffusive behavior of some raft-associated proteins across the plasma membrane.

  20. Chemical Reactive Anchoring Lipids with Different Performance for Cell Surface Re-engineering Application.

    Science.gov (United States)

    Vabbilisetty, Pratima; Boron, Mallorie; Nie, Huan; Ozhegov, Evgeny; Sun, Xue-Long

    2018-02-28

    Introduction of selectively chemical reactive groups at the cell surface enables site-specific cell surface labeling and modification opportunity, thus facilitating the capability to study the cell surface molecular structure and function and the molecular mechanism it underlies. Further, it offers the opportunity to change or improve a cell's functionality for interest of choice. In this study, two chemical reactive anchor lipids, phosphatidylethanolamine-poly(ethylene glycol)-dibenzocyclooctyne (DSPE-PEG 2000 -DBCO) and cholesterol-PEG-dibenzocyclooctyne (CHOL-PEG 2000 -DBCO) were synthesized and their potential application for cell surface re-engineering via lipid fusion were assessed with RAW 264.7 cells as a model cell. Briefly, RAW 264.7 cells were incubated with anchor lipids under various concentrations and at different incubation times. The successful incorporation of the chemical reactive anchor lipids was confirmed by biotinylation via copper-free click chemistry, followed by streptavidin-fluorescein isothiocyanate binding. In comparison, the cholesterol-based anchor lipid afforded a higher cell membrane incorporation efficiency with less internalization than the phospholipid-based anchor lipid. Low cytotoxicity of both anchor lipids upon incorporation into the RAW 264.7 cells was observed. Further, the cell membrane residence time of the cholesterol-based anchor lipid was evaluated with confocal microscopy. This study suggests the potential cell surface re-engineering applications of the chemical reactive anchor lipids.

  1. Chemical Reactive Anchoring Lipids with Different Performance for Cell Surface Re-engineering Application

    Science.gov (United States)

    2018-01-01

    Introduction of selectively chemical reactive groups at the cell surface enables site-specific cell surface labeling and modification opportunity, thus facilitating the capability to study the cell surface molecular structure and function and the molecular mechanism it underlies. Further, it offers the opportunity to change or improve a cell’s functionality for interest of choice. In this study, two chemical reactive anchor lipids, phosphatidylethanolamine–poly(ethylene glycol)–dibenzocyclooctyne (DSPE–PEG2000–DBCO) and cholesterol–PEG–dibenzocyclooctyne (CHOL–PEG2000–DBCO) were synthesized and their potential application for cell surface re-engineering via lipid fusion were assessed with RAW 264.7 cells as a model cell. Briefly, RAW 264.7 cells were incubated with anchor lipids under various concentrations and at different incubation times. The successful incorporation of the chemical reactive anchor lipids was confirmed by biotinylation via copper-free click chemistry, followed by streptavidin-fluorescein isothiocyanate binding. In comparison, the cholesterol-based anchor lipid afforded a higher cell membrane incorporation efficiency with less internalization than the phospholipid-based anchor lipid. Low cytotoxicity of both anchor lipids upon incorporation into the RAW 264.7 cells was observed. Further, the cell membrane residence time of the cholesterol-based anchor lipid was evaluated with confocal microscopy. This study suggests the potential cell surface re-engineering applications of the chemical reactive anchor lipids. PMID:29503972

  2. N-glycan sialylation in a silkworm-baculovirus expression system.

    Science.gov (United States)

    Suganuma, Masatoshi; Nomura, Tsuyoshi; Higa, Yukiko; Kataoka, Yukiko; Funaguma, Shunsuke; Okazaki, Hironobu; Suzuki, Takeo; Fujiyama, Kazuhito; Sezutsu, Hideki; Tatematsu, Ken-Ichiro; Tamura, Toshiki

    2018-02-09

    A silkworm-baculovirus system is particularly effective for producing recombinant proteins, including glycoproteins. However, N-glycan structures in silkworm differ from those in mammals. Glycoproteins in silkworm are secreted as pauci-mannose type N-glycans without sialic acid or galactose residues. Sialic acid on N-glycans plays important roles in protein functions. Therefore, we developed pathways for galactosylation and sialylation in silkworm. Sialylated N-glycans on proteins were successfully produced in silkworm by co-expressing galactosyltransferase and sialyltransferase and providing an external supply of a sialylation-related substrate. α2,3/α2,6 Sialylation to N-glycans was controlled by changing the type of sialyltransferase expressed in silkworm. Furthermore, the co-expression of N-acetylglucosaminyltransferase II facilitated the formation of additional di-sialylated N-glycan structures. Our results provide new information on the control of N-glycosylation in silkworm. Copyright © 2018 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

  3. Transferrin Sialylation in Smoking and Non-Smoking Pregnant Women with Intrauterine Growth Restriction.

    Science.gov (United States)

    Wrześniak, Marta; Kepinska, Marta; Bizoń, Anna; Milnerowicz-Nabzdyk, Ewa; Milnerowicz, Halina

    2015-01-01

    Transferrin (Tf) is a glycosylated protein responsible for transporting iron. Various sialylation levels of Tf are observed during physiological and pathological processes. We studied if the changes in iron stores as well as tobacco smoke may have an impact on foetal development and in consequence lead to intrauterine growth restriction (IUGR). In the third trimester of pregnancy, lower levels of 4-sialoTf isoform and higher levels of 5-sialoTf were observed in the serum of non-smoking women with IUGR in comparison to the control group. On the day of labour, level of 2-sialoTf was significantly lower and level of 3-sialo was Tf higher in the serum of non-smoking women. Level of 4-sialo was found lower in the serum of smoking women with IUGR than in the control group. The observed changes may suggest a connection between iron stores, transport of iron to the foetus and foetal development.

  4. Non-uniformly functionalized titanium carbide-based MXenes as an anchoring material for Li-S batteries: A first-principles calculation

    Science.gov (United States)

    Sim, Eun Seob; Chung, Yong-Chae

    2018-03-01

    In this study, the influence of the non-uniform surface of F- and O-functionalized Ti2C on the anchoring behavior of lithium polysulfide (LiPS) is investigated using density functional theory. In order to consider the non-uniform surface, the substitutional, vacancy, and S-trapped sites of F- and O-functionalized Ti2C are designed. The anchoring behavior is investigated considering the adsorption energy of LiPS, reactivity between Li atoms and the substrate, and the reduction state of the S atoms. On the F-substitutional site of the O-functionalized surface, it is confirmed that the suppressing mechanism changes from the neutralization of S atoms to the anchoring of LiPS. However, too strong of an interaction between Ti atoms exposed at the vacancy site and S atoms induces trapping of the S atom at the vacancies of both F- and O-functionalized surfaces. As a result of the trapping of the S atom, the use of active material decreases. In addition, the S-trapped site originated from the vacancy site does not affect the suppressing mechanism. In conclusion, to optimize the Ti2C-based MXene as an anchoring material for Li-S batteries, the preparation process should be focused on eliminating the vacancy of functional groups.

  5. Live-cell FRET imaging reveals clustering of the prion protein at the cell surface induced by infectious prions.

    Science.gov (United States)

    Tavares, Evandro; Macedo, Joana A; Paulo, Pedro M R; Tavares, Catarina; Lopes, Carlos; Melo, Eduardo P

    2014-07-01

    Prion diseases are associated to the conversion of the prion protein into a misfolded pathological isoform. The mechanism of propagation of protein misfolding by protein templating remains largely unknown. Neuroblastoma cells were transfected with constructs of the prion protein fused to both CFP-GPI-anchored and to YFP-GPI-anchored and directed to its cell membrane location. Live-cell FRET imaging between the prion protein fused to CFP or YFP was measured giving consistent values of 10±2%. This result was confirmed by fluorescence lifetime imaging microscopy and indicates intermolecular interactions between neighbor prion proteins. In particular, considering that a maximum FRET efficiency of 17±2% was determined from a positive control consisting of a fusion CFP-YFP-GPI-anchored. A stable cell clone expressing the two fusions containing the prion protein was also selected to minimize cell-to-cell variability. In both, stable and transiently transfected cells, the FRET efficiency consistently increased in the presence of infectious prions - from 4±1% to 7±1% in the stable clone and from 10±2% to 16±1% in transiently transfected cells. These results clearly reflect an increased clustering of the prion protein on the membrane in the presence of infectious prions, which was not observed in negative control using constructs without the prion protein and upon addition of non-infected brain. Our data corroborates the recent view that the primary site for prion conversion is the cell membrane. Since our fluorescent cell clone is not susceptible to propagate infectivity, we hypothesize that the initial event of prion infectivity might be the clustering of the GPI-anchored prion protein. Copyright © 2014 Elsevier B.V. All rights reserved.

  6. Bst1 is required for Candida albicans infecting host via facilitating cell wall anchorage of Glycosylphosphatidyl inositol anchored proteins

    Science.gov (United States)

    Liu, Wei; Zou, Zui; Huang, Xin; Shen, Hui; He, Li Juan; Chen, Si Min; Li, Li Ping; Yan, Lan; Zhang, Shi Qun; Zhang, Jun Dong; Xu, Zheng; Xu, Guo Tong; An, Mao Mao; Jiang, Yuan Ying

    2016-01-01

    Glycosylphosphatidyl inositol anchored proteins (GPI-APs) on fungal cell wall are essential for invasive infections. While the function of inositol deacylation of GPI-APs in mammalian cells has been previously characterized the impact of inositol deacylation in fungi and implications to host infection remains largely unexplored. Herein we describe our identification of BST1, an inositol deacylase of GPI-Aps in Candida albicans, was critical for GPI-APs cell wall attachment and host infection. BST1-deficient C. albicans (bst1Δ/Δ) was associated with severely impaired cell wall anchorage of GPI-APs and subsequen unmasked β-(1,3)-glucan. Consistent with the aberrant cell wall structures, bst1Δ/Δ strain did not display an invasive ability and could be recognized more efficiently by host immune systems. Moreover, BST1 null mutants or those expressing Bst1 variants did not display inositol deacylation activity and exhibited severely attenuated virulence and reduced organic colonization in a murine systemic candidiasis model. Thus, Bst1 can facilitate cell wall anchorage of GPI-APs in C. albicans by inositol deacylation, and is critical for host invasion and immune escape. PMID:27708385

  7. Sialylation of lipooligosaccharides is dispensable for the virulence of Haemophilus ducreyi in humans.

    Science.gov (United States)

    Spinola, Stanley M; Li, Wei; Fortney, Kate R; Janowicz, Diane M; Zwickl, Beth; Katz, Barry P; Munson, Robert S

    2012-02-01

    Sialylated glycoconjugates on the surfaces of mammalian cells play important roles in intercellular communication and self-recognition. The sialic acid preferentially expressed in human tissues is N-acetylneuraminic acid (Neu5Ac). In a process called molecular mimicry, many bacterial pathogens decorate their cell surface glycolipids with Neu5Ac. Incorporation of Neu5Ac into bacterial glycolipids promotes bacterial interactions with host cell receptors called Siglecs. These interactions affect bacterial adherence, resistance to serum killing and phagocytosis, and innate immune responses. Haemophilus ducreyi, the etiologic agent of chancroid, expresses lipooligosaccharides (LOS) that are highly sialylated. However, an H. ducreyi sialyltransferase (lst) mutant, whose LOS contain reduced levels of Neu5Ac, is fully virulent in human volunteers. Recently, a second sialyltransferase gene (Hd0053) was discovered in H. ducreyi, raising the possibility that Hd0053 compensated for the loss of lst during human infection. CMP-Neu5Ac is the obligate nucleotide sugar donor for all bacterial sialyltransferases; LOS derived from an H. ducreyi CMP-Neu5Ac synthetase (neuA) mutant has no detectable Neu5Ac. Here, we compared an H. ducreyi neuA mutant to its wild-type parent in several models of pathogenesis. In human inoculation experiments, the neuA mutant formed papules and pustules at rates that were no different than those of its parent. When grown in media with and without Neu5Ac supplementation, the neuA mutant and its parent had similar phenotypes in bactericidal, macrophage uptake, and dendritic cell activation assays. Although we cannot preclude a contribution of LOS sialylation to ulcerative disease, these data strongly suggest that sialylation of LOS is dispensable for H. ducreyi pathogenesis in humans.

  8. Citrobacter amalonaticus phytase on the cell surface of Pichia pastoris exhibits high pH stability as a promising potential feed supplement.

    Science.gov (United States)

    Li, Cheng; Lin, Ying; Huang, Yuanyuan; Liu, Xiaoxiao; Liang, Shuli

    2014-01-01

    Phytase expressed and anchored on the cell surface of Pichia pastoris avoids the expensive and time-consuming steps of protein purification and separation. Furthermore, yeast cells with anchored phytase can be used as a whole-cell biocatalyst. In this study, the phytase gene of Citrobacter amalonaticus was fused with the Pichia pastoris glycosylphosphatidylinositol (GPI)-anchored glycoprotein homologue GCW61. Phytase exposed on the cell surface exhibits a high activity of 6413.5 U/g, with an optimal temperature of 60°C. In contrast to secreted phytase, which has an optimal pH of 5.0, phytase presented on the cell surface is characterized by an optimal pH of 3.0. Moreover, our data demonstrate that phytase anchored on the cell surface exhibits higher pH stability than its secreted counterpart. Interestingly, our in vitro digestion experiments demonstrate that phytase attached to the cell surface is a more efficient enzyme than secreted phytase.

  9. Homozygous missense mutation (G56R in glycosylphosphatidylinositol-anchored high-density lipoprotein-binding protein 1 (GPI-HBP1 in two siblings with fasting chylomicronemia (MIM 144650

    Directory of Open Access Journals (Sweden)

    Hegele Robert A

    2007-09-01

    Full Text Available Abstract Background Mice with a deleted Gpihbp1 gene encoding glycosylphosphatidylinositol-anchored high-density lipoprotein-binding protein 1 (GPI-HBP1 develop severe chylomicronemia. We screened the coding regions of the human homologue – GPIHBP1 – from the genomic DNA of 160 unrelated adults with fasting chylomicronemia and plasma triglycerides >10 mmol/L, each of whom had normal sequence of the LPL and APOC2 genes. Results One patient with severe type 5 hyperlipoproteinemia (MIM 144650, fasting chylomicronemia and relapsing pancreatitis resistant to standard therapy was found to be homozygous for a novel GPIHBP1 missense variant, namely G56R. This mutation was absent from the genomes of 600 control subjects and 610 patients with hyperlipidemia. The GPIHBP1 G56 residue has been conserved throughout evolution and the G56R mutation was predicted to have compromised function. Her homozygous brother also had refractory chylomicronemia and relapsing pancreatitis together with early coronary heart disease. G56R heterozygotes in the family had fasting mild hypertriglyceridemia. Conclusion Thus, a very rare GPIHBP1 missense mutation appears to be associated with severe hypertriglyceridemia and chylomicronemia.

  10. Quantitative enzymatic production of sialylated galactooligosaccharides with an engineered sialidase from Trypanosoma rangeli

    DEFF Research Database (Denmark)

    Zeuner, Birgitte; Holck, Jesper; Perna, Valentina

    2016-01-01

    Sialylated galactooligosaccharides (GOS) represent a potential infant formula ingredient, which is believed to contribute with a combination of the beneficial properties of the prebiotic GOS as well as of sialylated human milk oligosaccharides. Sialylated GOS do not exist in natural milk, but can...

  11. Sialylated Autoantigen-Reactive IgG Antibodies Attenuate Disease Development in Autoimmune Mouse Models of Lupus Nephritis and Rheumatoid Arthritis

    Directory of Open Access Journals (Sweden)

    Yannic C. Bartsch

    2018-06-01

    Full Text Available Pro- and anti-inflammatory effector functions of IgG antibodies (Abs depend on their subclass and Fc glycosylation pattern. Accumulation of non-galactosylated (agalactosylated; G0 IgG Abs in the serum of rheumatoid arthritis and systemic lupus erythematosus (SLE patients reflects severity of the diseases. In contrast, sialylated IgG Abs are responsible for anti-inflammatory effects of the intravenous immunoglobulin (pooled human serum IgG from healthy donors, administered in high doses (2 g/kg to treat autoimmune patients. However, whether low amounts of sialylated autoantigen-reactive IgG Abs can also inhibit autoimmune diseases is hardly investigated. Here, we explore whether sialylated autoantigen-reactive IgG Abs can inhibit autoimmune pathology in different mouse models. We found that sialylated IgG auto-Abs fail to induce inflammation and lupus nephritis in a B cell receptor (BCR transgenic lupus model, but instead are associated with lower frequencies of pathogenic Th1, Th17 and B cell responses. In accordance, the transfer of small amounts of immune complexes containing sialylated IgG Abs was sufficient to attenuate the development of nephritis. We further showed that administration of sialylated collagen type II (Col II-specific IgG Abs attenuated the disease symptoms in a model of Col II-induced arthritis and reduced pathogenic Th17 cell and autoantigen-specific IgG Ab responses. We conclude that sialylated autoantigen-specific IgG Abs may represent a promising tool for treating pathogenic T and B cell immune responses in autoimmune diseases.

  12. Mutations in PIGY: expanding the phenotype of inherited glycosylphosphatidylinositol deficiencies.

    Science.gov (United States)

    Ilkovski, Biljana; Pagnamenta, Alistair T; O'Grady, Gina L; Kinoshita, Taroh; Howard, Malcolm F; Lek, Monkol; Thomas, Brett; Turner, Anne; Christodoulou, John; Sillence, David; Knight, Samantha J L; Popitsch, Niko; Keays, David A; Anzilotti, Consuelo; Goriely, Anne; Waddell, Leigh B; Brilot, Fabienne; North, Kathryn N; Kanzawa, Noriyuki; Macarthur, Daniel G; Taylor, Jenny C; Kini, Usha; Murakami, Yoshiko; Clarke, Nigel F

    2015-11-01

    Glycosylphosphatidylinositol (GPI)-anchored proteins are ubiquitously expressed in the human body and are important for various functions at the cell surface. Mutations in many GPI biosynthesis genes have been described to date in patients with multi-system disease and together these constitute a subtype of congenital disorders of glycosylation. We used whole exome sequencing in two families to investigate the genetic basis of disease and used RNA and cellular studies to investigate the functional consequences of sequence variants in the PIGY gene. Two families with different phenotypes had homozygous recessive sequence variants in the GPI biosynthesis gene PIGY. Two sisters with c.137T>C (p.Leu46Pro) PIGY variants had multi-system disease including dysmorphism, seizures, severe developmental delay, cataracts and early death. There were significantly reduced levels of GPI-anchored proteins (CD55 and CD59) on the surface of patient-derived skin fibroblasts (∼20-50% compared with controls). In a second, consanguineous family, two siblings had moderate development delay and microcephaly. A homozygous PIGY promoter variant (c.-540G>A) was detected within a 7.7 Mb region of autozygosity. This variant was predicted to disrupt a SP1 consensus binding site and was shown to be associated with reduced gene expression. Mutations in PIGY can occur in coding and non-coding regions of the gene and cause variable phenotypes. This article contributes to understanding of the range of disease phenotypes and disease genes associated with deficiencies of the GPI-anchor biosynthesis pathway and also serves to highlight the potential importance of analysing variants detected in 5'-UTR regions despite their typically low coverage in exome data. © The Author 2015. Published by Oxford University Press.

  13. Anchor-dependent lipofection with non-glycerol based cytofectins containing single 2-hydroxyethyl head groups.

    Science.gov (United States)

    Venkata Srilakshmi, Gollapudi; Sen, Joyeeta; Chaudhuri, Arabinda; Ramadas, Yerramsetti; Madhusudhana Rao, Nalam

    2002-02-15

    Detailed structure-activity investigations aimed at probing the anchor chain length dependency for glycerol-based lipofectins have been reported previously. Herein, we report on the first detailed investigation on the anchor-dependent transfection biology of non-glycerol based simple monocationic cytofectins containing single 2-hydroxyethyl head group functionality using 11 new structural analogs of our previously published first generation of non-glycerol based transfection lipids (lipids 1-11). The C-14 and C-16 analogs of DOMHAC (lipids 4 and 5, respectively) were found to be remarkably efficient in transfecting COS-1 cells. In addition, the present anchor-dependency investigation also revealed that the C-14 analog of DOHEMAB (lipid 10) is significantly efficient in transfecting both COS-1 and NIH3T3 cells. Our results also indicate that too strong lipid-DNA interactions might result in weaker transfection for non-glycerol based cationic lipids. In summary, the anchor-dependence investigations presented here convincingly demonstrate that non-glycerol based cationic lipids containing a single hydroxyethyl head group and hydrophobic C-14 or C-16 anchors are promising non-toxic cationic transfection lipids for future use in liposomal gene delivery.

  14. Climate Prediction Center(CPC)Daily GOES Precipitation Index (GPI)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — GOES Precipitation Index (GPI) is a precipitation estimation algorithm. The GPI technique estimates tropical rainfall using cloud-top temperature as the sole...

  15. ST6GalNAc-I controls expression of sialyl-Tn antigen in gastrointestinal tissues

    DEFF Research Database (Denmark)

    Marcos, Nuno T; Bennett, Eric P; Gomes, Joana

    2011-01-01

    Sialyl-Tn is a simple mucin-type carbohydrate antigen aberrantly expressed in gastrointestinal adenocarcinomas and in the precursor lesion intestinal metaplasia. Sialyl-Tn tumour expression is an independent indicator of poor prognosis. We have previously shown in vitro that ST6GalNAc-I and ST6GalNAc......-II sialyltransferases can synthesize sialyl-Tn. The aim of the present study was to establish whether ST6GalNAc-I is the major enzyme responsible for the expression of sialyl-Tn. We used a model of CHO-ldlD cells producing only MUC1-Tn glycoform and showed that ST6GalNAc-I is the key-enzyme leading to sialyl......-Tn biosynthesis. We developed novel monoclonal antibodies specific for ST6GalNAc-I and evaluated its expression in gastrointestinal tissues. ST6GalNAc-I was detected in normal colon mucosa co-localized with O-acetylated sialyl-Tn. Expression was largely unaltered in colorectal adenocarcinomas. In contrast, we...

  16. Electron detachment dissociation of fluorescently labeled sialylated oligosaccharides.

    Science.gov (United States)

    Zhou, Wen; Håkansson, Kristina

    2011-12-01

    We explored the application of electron detachment dissociation (EDD) and infrared multiphoton dissociation (IRMPD) tandem mass spectrometry to fluorescently labeled sialylated oligosaccharides. Standard sialylated oligosaccharides and a sialylated N-linked glycan released from human transferrin were investigated. EDD yielded extensive glycosidic cleavages and cross-ring cleavages in all cases studied, consistently providing complementary structural information compared with infrared multiphoton dissociation. Neutral losses and satellite ions such as C-2H ions were also observed following EDD. In addition, we examined the influence of different fluorescent labels. The acidic label 2-aminobenzoic acid (2-AA) enhanced signal abundance in negative-ion mode. However, few cross-ring fragments were observed for 2-AA-labeled oligosaccharides. The neutral label 2-aminobenzamide (2-AB) resulted in more cross-ring cleavages compared with 2-AA-labeled species, but not as extensive fragmentation as for native oligosaccharides, likely resulting from altered negative charge locations from introduction of the fluorescent tag. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  17. Novel PIGT Variant in Two Brothers: Expansion of the Multiple Congenital Anomalies-Hypotonia Seizures Syndrome 3 Phenotype

    Directory of Open Access Journals (Sweden)

    Nadia Skauli

    2016-11-01

    Full Text Available Biallelic PIGT variants were previously reported in seven patients from three families with Multiple Congenital Anomalies-Hypotonia Seizures Syndrome 3 (MCAHS3, characterized by epileptic encephalopathy, hypotonia, global developmental delay/intellectual disability, cerebral and cerebellar atrophy, craniofacial dysmorphisms, and skeletal, ophthalmological, cardiac, and genitourinary abnormalities. We report a novel homozygous PIGT missense variant c.1079G>T (p.Gly360Val in two brothers with several of the typical features of MCAHS3, but in addition, pyramidal tract neurological signs. Notably, they are the first patients with MCAHS3 without skeletal, cardiac, or genitourinary anomalies. PIGT encodes a crucial subunit of the glycosylphosphatidylinositol (GPI transamidase complex, which catalyzes the attachment of proteins to GPI-anchors, attaching the proteins to the cell membrane. In vitro studies in cells from the two brothers showed reduced levels of GPI-anchors and GPI-anchored proteins on the cell surface, supporting the pathogenicity of the novel PIGT variant.

  18. Redox Status of β2GPI in Different Stages of Diabetic Angiopathy

    Directory of Open Access Journals (Sweden)

    Jun Ma

    2016-01-01

    Full Text Available We explored the redox status of beta 2 glycoprotein I (β2GPI in different stages of diabetic angiopathy. Type 2 diabetes mellitus (T2DM had a significantly lower proportion of reduced β2GPI as compared to healthy controls (p0.05. The mild-A-stenosis group and mild-diabetic retinopathy (DR groups had higher proportion of reduced β2GPI than their severely affected counterparts. The mild-slow nerve conduction velocity (NCVS group had higher proportion of reduced β2GPI than normal nerve conduction velocity (NCVN group and severe-NCVS groups. The proportion of reduced β2GPI was in positive correlation with 24 h urine microalbumin and total urine protein, and the proportion of reduced β2GPI was in negative correlation with serum and skin advanced glycation end products (AGEs. Taken together, our data implicate that the proportion of reduced β2GPI increased in the early stage of angiopathy and decreased with the aggravation of angiopathy.

  19. Lectin binding assays for in-process monitoring of sialylation in protein production.

    Science.gov (United States)

    Xu, Weiduan; Chen, Jianmin; Yamasaki, Glenn; Murphy, John E; Mei, Baisong

    2010-07-01

    Many therapeutic proteins require appropriate glycosylation for their biological activities and plasma half life. Coagulation factor VIII (FVIII) is a glycoprotein which has extensive post-translational modification by N-linked glycosylation. The terminal sialic acid in the N-linked glycans of FVIII is required for maximal circulatory half life. The extent of FVIII sialylation can be determined by high pH anion-exchange chromatography coupled with a pulse electrochemical detector (HPAEC-PED), but this requires a large amount of purified protein. Using FVIII as a model, the objective of the present study was to develop assays that enable detection and prediction of sialylation deficiency at an early stage in the process and thus prevent downstream product quality excursions. Lectin ECA (Erythrina Cristagalli) binds to unsialylated Galbeta1-4 GlcNAc and the ECA-binding level (i.e., terminal Gal(beta1-4) exposure) is inversely proportional to the level of sialylation. By using ECA, a cell-based assay was developed to measure the global sialylation profile in FVIII producing cells. To examine the Galbeta1-4 exposure on the FVIII molecule in bioreactor tissue culture fluid (TCF), an ELISA-based ECA-FVIII binding assay was developed. The ECA-binding specificity in both assays was assessed by ECA-specific sugar inhibitors and neuraminidase digestion. The ECA-binding specificity was also independently confirmed by a ST3GAL4 siRNA knockdown experiment. To establish the correlation between Galbeta1-4 exposure and the HPAEC-PED determined FVIII sialylation value, the FVIII containing bioreactor TCF and the purified FVIII samples were tested with ECA ELISA binding assay. The results indicated an inverse correlation between ECA binding and the corresponding HPAEC-PED sialylation value. The ECA-binding assays are cost effective and can be rapidly performed, thereby making them effective for in-process monitoring of protein sialylation.

  20. Therapeutic efficacy of PD-L1 blockade in a breast cancer model is enhanced by cellular vaccines expressing B7-1 and glycolipid-anchored IL-12.

    Science.gov (United States)

    Bozeman, Erica N; He, Sara; Shafizadeh, Yalda; Selvaraj, Periasamy

    2016-01-01

    Immunotherapeutic approaches have emerged as promising strategies to treat various cancers, including breast cancer. A single approach, however, is unlikely to effectively combat the complex, immune evasive strategies found within the tumor microenvironment, thus novel, effective combination treatments must be explored. In this study, we investigated the efficacy of a combination therapy consisting of PD-L1 immune checkpoint blockade and whole cell vaccination in a HER-2 positive mouse model of breast cancer. We demonstrate that tumorigenicity is completely abrogated when adjuvanted with immune stimulatory molecules (ISMs) B7-1 and a cell-surface anchored (GPI) form of IL-12 or GM-CSF. Irradiated cellular vaccines expressing the combination of adjuvants B7-1 and GPI-IL-12 completely inhibited tumor formation which was correlative with robust HER-2 specific CTL activity. However, in a therapeutic setting, both cellular vaccination and PD-L1 blockade induced only 10-20% tumor regression when administered alone but resulted in 50% tumor regression as a combination therapy. This protection was significantly hindered following CD4 or CD8 depletion indicating the essential role played by cellular immunity. Collectively, these pre-clinical studies provide a strong rationale for further investigation into the efficacy of combination therapy with tumor cell vaccines adjuvanted with membrane-anchored ISMs along with PD-L1 blockade for the treatment of breast cancer.

  1. The automated data processing architecture for the GPI Exoplanet Survey

    Science.gov (United States)

    Wang, Jason J.; Perrin, Marshall D.; Savransky, Dmitry; Arriaga, Pauline; Chilcote, Jeffrey K.; De Rosa, Robert J.; Millar-Blanchaer, Maxwell A.; Marois, Christian; Rameau, Julien; Wolff, Schuyler G.; Shapiro, Jacob; Ruffio, Jean-Baptiste; Graham, James R.; Macintosh, Bruce

    2017-09-01

    The Gemini Planet Imager Exoplanet Survey (GPIES) is a multi-year direct imaging survey of 600 stars to discover and characterize young Jovian exoplanets and their environments. We have developed an automated data architecture to process and index all data related to the survey uniformly. An automated and flexible data processing framework, which we term the GPIES Data Cruncher, combines multiple data reduction pipelines together to intelligently process all spectroscopic, polarimetric, and calibration data taken with GPIES. With no human intervention, fully reduced and calibrated data products are available less than an hour after the data are taken to expedite follow-up on potential objects of interest. The Data Cruncher can run on a supercomputer to reprocess all GPIES data in a single day as improvements are made to our data reduction pipelines. A backend MySQL database indexes all files, which are synced to the cloud, and a front-end web server allows for easy browsing of all files associated with GPIES. To help observers, quicklook displays show reduced data as they are processed in real-time, and chatbots on Slack post observing information as well as reduced data products. Together, the GPIES automated data processing architecture reduces our workload, provides real-time data reduction, optimizes our observing strategy, and maintains a homogeneously reduced dataset to study planet occurrence and instrument performance.

  2. Electron Detachment Dissociation (EDD) of Fluorescently Labeled Sialylated Oligosaccharides

    Science.gov (United States)

    Zhou, Wen; Håkansson, Kristina

    2012-01-01

    We explored the application of electron detachment dissociation (EDD) and infrared multiphoton dissociation (IRMPD) tandem mass spectrometry to fluorescently labeled sialylated oligosaccharides. Standard sialylated oligosaccharides and a sialylated N-linked glycan released from human transferrin were investigated. EDD yielded extensive glycosidic cleavages and cross-ring cleavages in all cases studied, consistently providing complementary structural information compared to IRMPD. Neutral losses and satellite ions such as C – 2H ions were also observed following EDD. In addition, we examined the influence of different fluorescent labels. The acidic label 2-aminobenzoic acid (2-AA) enhanced signal abundance in negative-ion mode. However, few cross-ring fragments were observed for 2-AA labeled oligosaccharides. The neutral label 2-aminobenzamide (2-AB) resulted in more cross-ring cleavages compared to 2-AA labeled species, but not as extensive fragmentation as for native oligosaccharides, likely resulting from altered negative charge locations from introduction of the fluorescent tag. PMID:22120881

  3. Methodological developments in US state-level Genuine Progress Indicators: toward GPI 2.0

    Science.gov (United States)

    Bagstad, Kenneth J.; Berik, Günseli; Gaddis, Erica J. Brown

    2014-01-01

    The Genuine Progress Indicator (GPI) has emerged as an important monetary measure of economic well-being. Unlike mainstream economic indicators, primarily Gross Domestic Product (GDP), the GPI accounts for both the benefits and costs of economic production across diverse economic, social, and environmental domains in a more comprehensive manner. Recently, the GPI has gained traction in subnational policy in the United States, with GPI studies being conducted in a number of states and with their formal adoption by several state governments. As the GPI is applied in different locations, new methods are developed, different data sources are available, and new issues of policy relevance are addressed using its component indicators. This has led to a divergence in methods, reducing comparability between studies and yielding results that are of varying methodological sophistication. In this study, we review the “state of the art” in recent US state-level GPI studies, focusing on those from Hawaii, Maryland, Ohio, Utah, and Vermont. Through adoption of a consistent approach, these and future GPI studies could utilize a framework that supports more uniform, comparable, and accurate measurements of progress. We also identify longer-term issues, particularly related to treatment of nonrenewable resource depletion, government spending, income inequality, and ecosystem services. As these issues are successfully addressed and disseminated, a “GPI 2.0” will emerge that better measures economic well-being and has greater accuracy and policy relevance than past GPI measurements. As the GPI expands further into mainstream policy analysis, a more formal process by which methods could be updated, standardized, and applied is needed.

  4. Sialic Acid Glycobiology Unveils Trypanosoma cruzi Trypomastigote Membrane Physiology.

    Directory of Open Access Journals (Sweden)

    Andrés B Lantos

    2016-04-01

    Full Text Available Trypanosoma cruzi, the flagellate protozoan agent of Chagas disease or American trypanosomiasis, is unable to synthesize sialic acids de novo. Mucins and trans-sialidase (TS are substrate and enzyme, respectively, of the glycobiological system that scavenges sialic acid from the host in a crucial interplay for T. cruzi life cycle. The acquisition of the sialyl residue allows the parasite to avoid lysis by serum factors and to interact with the host cell. A major drawback to studying the sialylation kinetics and turnover of the trypomastigote glycoconjugates is the difficulty to identify and follow the recently acquired sialyl residues. To tackle this issue, we followed an unnatural sugar approach as bioorthogonal chemical reporters, where the use of azidosialyl residues allowed identifying the acquired sugar. Advanced microscopy techniques, together with biochemical methods, were used to study the trypomastigote membrane from its glycobiological perspective. Main sialyl acceptors were identified as mucins by biochemical procedures and protein markers. Together with determining their shedding and turnover rates, we also report that several membrane proteins, including TS and its substrates, both glycosylphosphatidylinositol-anchored proteins, are separately distributed on parasite surface and contained in different and highly stable membrane microdomains. Notably, labeling for α(1,3Galactosyl residues only partially colocalize with sialylated mucins, indicating that two species of glycosylated mucins do exist, which are segregated at the parasite surface. Moreover, sialylated mucins were included in lipid-raft-domains, whereas TS molecules are not. The location of the surface-anchored TS resulted too far off as to be capable to sialylate mucins, a role played by the shed TS instead. Phosphatidylinositol-phospholipase-C activity is actually not present in trypomastigotes. Therefore, shedding of TS occurs via microvesicles instead of as a fully

  5. Genome-wide in silico identification of GPI proteins in Mycosphaerella fijiensis and transcriptional analysis of two GPI-anchored β-1,3-glucanosyltransferases.

    Science.gov (United States)

    Kantún-Moreno, Nuvia; Vázquez-Euán, Roberto; Tzec-Simá, Miguel; Peraza-Echeverría, Leticia; Grijalva-Arango, Rosa; Rodríguez-García, Cecilia; James, Andrew C; Ramírez-Prado, Jorge; Islas-Flores, Ignacio; Canto-Canché, Blondy

    2013-01-01

    The hemibiotrophic fungus Mycosphaerella fijiensis is the causal agent of black Sigatoka (BS), the most devastating foliar disease in banana (Musa spp.) worldwide. Little is known about genes that are important during M. fijiensis-Musa sp. interaction. The fungal cell wall is an attractive area of study because it is essential for maintenance of cellular homeostasis and it is the most external structure in the fungal cell and therefore mediates the interaction of the pathogen with the host. In this manuscript we describe the in silico identification of glycosyl phosphatidylinositol-protein (GPI) family in M. fijiensis, and the analysis of two β-1,3-glucanosyltrans-ferases (Gas), selected by homology with fungal pathogenicity factors. Potential roles in pathogenesis were evaluated through analyzing expression during different stages of black Sigatoka disease, comparing expression data with BS symptoms and fungal biomass inside leaves. Real-time quantitative RT-PCR showed nearly constant expression of MfGAS1 with slightly increases (about threefold) in conidia and at speck-necrotrophic stage during banana-pathogen interaction. Conversely, MfGAS2 expression was increased during biotrophy (about seven times) and reached a maximum at speck (about 23 times) followed by a progressive decrease in next stages, suggesting an active role in M. fijiensis pathogenesis.

  6. Antibody-based enzyme-linked lectin assay (ABELLA) for the sialylated recombinant human erythropoietin present in culture supernatant.

    Science.gov (United States)

    Kim, Hyoung Jin; Lee, Seung Jae; Kim, Hong-Jin

    2008-11-04

    The terminal sialic acid of human erythropoietin (hEPO) is essential for in vivo activity. The current resorcinol and HPLC methods for analyzing alpha2,3-linked sialic acid require more than a microgram of purified rhEPO, and purification takes a great deal of time and labor. In this study, we assessed the use of an antibody-based enzyme-linked lectin assay (ABELLA) for analyzing non-purified recombinant hEPO (rhEPO). The major problem of this method was the high background due to terminal sialylation of components of the assay (antibody and bovine serum albumin) other than rhEPO. To solve this problem, we used a monoclonal antibody (Mab 287) to capture the rhEPO, and oxidized the bovine serum albumin used for blocking with meta-periodate. The sialic acid content of non-purified rhEPO measured by ABELLA was similar to that obtained by the resorcinol method on purified rhEPO. ABELLA has advantages such as adaptability and need for minimal amounts of rhEPO (40 ng/ml). Our observations suggest that ABELLA should reduce the time and labor needed to improve culture conditions so as to increase protein sialylation, and also facilitate the study of sialylation mechanisms.

  7. Phospholipase D specific for the phosphatidylinositol anchor of cell-surface proteins is abundant in plasma

    International Nuclear Information System (INIS)

    Low, M.G.; Prasad, A.R.S.

    1988-01-01

    An enzyme activity capable of degrading the glycosyl-phosphatidylinositol membrane anchor of cell-surface proteins has previously been reported in a number of mammalian tissues. The experiments reported here demonstrate that this anchor-degrading activity is also abundant in mammalian plasma. The activity was inhibited by EGTA or 1,10-phenanthroline. It was capable of removing the anchor from alkaline phosphatase, 5'-nucleotidase, and variant surface glycoprotein but had little or no activity toward phosphatidylinositol or phosphatidylcholine. Phosphatidic acid was the only 3 H-labeled product when this enzyme hydrolyzed [ 3 H]myristate-labeled variant surface glycoprotein. It could be distinguished from the Ca 2 =-dependent inositol phospholipid-specific phospholipase C activity in several rat tissues on the basis of its molecular size and its sensitivity to 1,10-phenanthroline. The data therefore suggest that this activity is due to a phospholipase D with specificity for glycosylphosphatidylinositol structures. Although the precise physiological function of this anchor-specific phospholipase D remains to be determined, these findings indicate that it could play an important role in regulating the expression and release of cell-surface proteins in vivo

  8. Expression of Lewisa, Sialyl Lewisa, Lewisx, Sialyl Lewisx, Antigens as Prognostic Factors in Patients with Colorectal Cancer

    Directory of Open Access Journals (Sweden)

    Tohru Nakagoe

    2000-01-01

    Full Text Available BACKGROUND: Altered expression of blood group-related carbohydrate antigens such as sialyl Lewis (Lex antigen in tumours is associated with tumour progression behaviour and subsequent prognosis. However, the prognostic value of the expression of Le-related antigens in colorectal tumours remains unclear.

  9. The influence of maternal smoking on transferrin sialylation and fetal biometric parameters.

    Science.gov (United States)

    Wrześniak, Marta; Królik, Małgorzata; Kepinska, Marta; Milnerowicz, Halina

    2016-10-01

    Transferrin is a glycosylated protein responsible for transporting iron, an essential metal responsible for proper fetal development. Tobacco is a heavily used xenobiotic having a negative impact on the human body and pregnancy outcomes. Aims of this study was to examine the influence of tobacco smoking on transferrin sialic acid residues and their connection with fetal biometric parameters in women with iron-deficiency. The study involved 173 samples from pregnant women, smokers and non-smokers, iron deficient and not. Transferrin sialylation was determined by capillary electrophoresis. The cadmium (Cd) level was measured by atomic absorption and the sialic acid concentration by the resorcinol method. Women with iron deficiencies who smoked gave birth earlier than non-smoking, non-iron-deficient women. The Cd level, but not the cotinine level, was positively correlated with transferrin sialylation in the blood of iron-deficient women who smoked; 3-, 4-, 5- and 6-sialoTf correlated negatively with fetal biometric parameters in the same group. It has been shown the relationship between Cd from tobacco smoking and fetal biometric parameters observed only in the iron deficient group suggests an additive effect of these two factors, and indicate that mothers with anemia may be more susceptible to Cd toxicity and disturbed fetal development. Copyright © 2016 Elsevier B.V. All rights reserved.

  10. Prostasin-dependent activation of epithelial Na+ channels by low plasmin concentrations

    DEFF Research Database (Denmark)

    Svenningsen, Per; Uhrenholt, Torben R; Palarasah, Yaseelan

    2009-01-01

    by which plasmin stimulates ENaC activity. Cy3-labeled plasmin was found to bind to the surface of the mouse cortical collecting duct cell line, M-1. Binding depended on a glycosylphosphatidylinositol (GPI)-anchored protein. Biotin-label transfer showed that plasmin interacted with the GPI-anchored protein...... plasmin-stimulated ENaC current in monolayers of M-1 cells at low plasmin concentration (1-4 microg/ml). At a high plasmin concentration of 30 microg/ml, there was no difference between cell layers treated with or without PI-PLC. Knockdown of prostasin attenuated binding of plasmin to M1 cells and blocked...... labeling of M-1 cells. Pretreatment with plasmin abolished labeling of M-1 cells in a prostasin-dependent way. We conclude that, at low concentrations, plasmin interacts with GPI-anchored prostasin, which leads to cleavage of the gamma-subunit and activation of ENaC, while at higher concentrations, plasmin...

  11. PrP Knockout Cells Expressing Transmembrane PrP Resist Prion Infection.

    Science.gov (United States)

    Marshall, Karen E; Hughson, Andrew; Vascellari, Sarah; Priola, Suzette A; Sakudo, Akikazu; Onodera, Takashi; Baron, Gerald S

    2017-01-15

    Glycosylphosphatidylinositol (GPI) anchoring of the prion protein (PrP C ) influences PrP C misfolding into the disease-associated isoform, PrP res , as well as prion propagation and infectivity. GPI proteins are found in cholesterol- and sphingolipid-rich membrane regions called rafts. Exchanging the GPI anchor for a nonraft transmembrane sequence redirects PrP C away from rafts. Previous studies showed that nonraft transmembrane PrP C variants resist conversion to PrP res when transfected into scrapie-infected N2a neuroblastoma cells, likely due to segregation of transmembrane PrP C and GPI-anchored PrP res in distinct membrane environments. Thus, it remained unclear whether transmembrane PrP C might convert to PrP res if seeded by an exogenous source of PrP res not associated with host cell rafts and without the potential influence of endogenous expression of GPI-anchored PrP C To further explore these questions, constructs containing either a C-terminal wild-type GPI anchor signal sequence or a nonraft transmembrane sequence containing a flexible linker were expressed in a cell line derived from PrP knockout hippocampal neurons, NpL2. NpL2 cells have physiological similarities to primary neurons, representing a novel and advantageous model for studying transmissible spongiform encephalopathy (TSE) infection. Cells were infected with inocula from multiple prion strains and in different biochemical states (i.e., membrane bound as in brain microsomes from wild-type mice or purified GPI-anchorless amyloid fibrils). Only GPI-anchored PrP C supported persistent PrP res propagation. Our data provide strong evidence that in cell culture GPI anchor-directed membrane association of PrP C is required for persistent PrP res propagation, implicating raft microdomains as a location for conversion. Mechanisms of prion propagation, and what makes them transmissible, are poorly understood. Glycosylphosphatidylinositol (GPI) membrane anchoring of the prion protein (PrP C

  12. Failure Capacity Evaluation for Anchor System of NPP Facilities by using a Shaking Table Test

    International Nuclear Information System (INIS)

    Kwon, Hyung O; Jung, Min Ki; Park, Jin Wan; Lim, Ji Hoon

    2010-02-01

    This study investigate the destructive influence of crack locations on the anchor performance to evaluate the seismic performance of NPP equipment anchored on damaged concrete. For this purpose, small-scale specimens were fabricated according to the following three cases: 1) with a non-damaged anchor; 2) with cracks running through the anchor; and 3) with cracks along the expected corn-shape fracture away from the anchor. The result verified with the finite element method is as follows: In the first and second cases that is, with a non-damaged anchor and with cracks running through the anchor destruction occurred at the anchor steel. In the third case that is, with cracks around the anchor, a 30% decline in the seismic performance was identified. This result indicates that evaluation of seismic performance and relevant reinforcement are required when cracks occur away from the anchor along the expected destructive surface

  13. P53 and cancer-associated sialylated glycans are surrogate markers of cancerization of the bladder associated with Schistosoma haematobium infection.

    Directory of Open Access Journals (Sweden)

    Júlio Santos

    2014-12-01

    Full Text Available Bladder cancer is a significant health problem in rural areas of Africa and the Middle East where Schistosoma haematobium is prevalent, supporting an association between malignant transformation and infection by this blood fluke. Nevertheless, the molecular mechanisms linking these events are poorly understood. Bladder cancers in infected populations are generally diagnosed at a late stage since there is a lack of non-invasive diagnostic tools, hence enforcing the need for early carcinogenesis markers.Forty-three formalin-fixed paraffin-embedded bladder biopsies of S. haematobium-infected patients, consisting of bladder tumours, tumour adjacent mucosa and pre-malignant/malignant urothelial lesions, were screened for bladder cancer biomarkers. These included the oncoprotein p53, the tumour proliferation rate (Ki-67>17%, cell-surface cancer-associated glycan sialyl-Tn (sTn and sialyl-Lewisa/x (sLea/sLex, involved in immune escape and metastasis. Bladder tumours of non-S. haematobium etiology and normal urothelium were used as controls. S. haematobium-associated benign/pre-malignant lesions present alterations in p53 and sLex that were also found in bladder tumors. Similar results were observed in non-S. haematobium associated tumours, irrespectively of their histological nature, denoting some common molecular pathways. In addition, most benign/pre-malignant lesions also expressed sLea. However, proliferative phenotypes were more prevalent in lesions adjacent to bladder tumors while sLea was characteristic of sole benign/pre-malignant lesions, suggesting it may be a biomarker of early carcionogenesis associated with the parasite. A correlation was observed between the frequency of the biomarkers in the tumor and adjacent mucosa, with the exception of Ki-67. Most S. haematobium eggs embedded in the urothelium were also positive for sLea and sLex. Reinforcing the pathologic nature of the studied biomarkers, none was observed in the healthy urothelium

  14. Formation and properties of surface-anchored polymer assemblies with tunable physico-chemical characteristics

    Science.gov (United States)

    Wu, Tao

    We describe two new methodologies leading to the formation of novel surface-anchored polymer assemblies on solid substrates. While the main goal is to understand the fundamentals pertaining to the preparation and properties of the surface-bound polymer assemblies (including neutral and chargeable polymers), several examples also are mentioned throughout the Thesis that point out to practical applications of such structures. The first method is based on generating assemblies comprising anchored polymers with a gradual variation of grafting densities on solid substrates. These structures are prepared by first covering the substrate with a molecular gradient of the polymerization initiator, followed by polymerization from these substrate-bound initiator centers ("grafting from"). We apply this technique to prepare grafting density gradients of poly(acryl amide) (PAAm) and poly(acrylic acid) (PAA) on silica-covered substrates. We show that using the grafting density gradient geometry, the characteristics of surface-anchored polymers in both the low grafting density ("mushroom") regime as well as the high grafting density ("brush") regime can be accessed conveniently on a single sample. We use a battery of experimental methods, including Fourier transform infrared spectroscopy (FTIR), Near-edge absorption fine structure spectroscopy (NEXAFS), contact angle, ellipsometry, to study the characteristics of the surface-bound polymer layers. We also probe the scaling laws of neutral polymer as a function of grafting density, and for weak polyelectrolyte, in addition to the grafting density, we study the affect of solution ionic strength and pH values. In the second novel method, which we coined as "mechanically assisted polymer assembly" (MAPA), we form surface anchored polymers by "grafting from" polymerization initiators deposited on elastic surfaces that have been previously extended uniaxially by a certain length increment, Deltax. Upon releasing the strain in the

  15. The role of Gpi-anchored axonal glycoproteins in neural development and neurological disorders.

    Science.gov (United States)

    Gennarini, Gianfranco; Bizzoca, Antonella; Picocci, Sabrina; Puzzo, Daniela; Corsi, Patrizia; Furley, Andrew J W

    2017-06-01

    This review article focuses on the Contactin (CNTN) subset of the Immunoglobulin supergene family (IgC2/FNIII molecules), whose components share structural properties (the association of Immunoglobulin type C2 with Fibronectin type III domains), as well as a general role in cell contact formation and axonal growth control. IgC2/FNIII molecules include 6 highly related components (CNTN 1-6), associated with the cell membrane via a Glycosyl Phosphatidyl Inositol (GPI)-containing lipid tail. Contactin 1 and Contactin 2 share ~50 (49.38)% identity at the aminoacid level. They are components of the cell surface, from which they may be released in soluble forms. They bind heterophilically to multiple partners in cis and in trans, including members of the related L1CAM family and of the Neurexin family Contactin-associated proteins (CNTNAPs or Casprs). Such interactions are important for organising the neuronal membrane, as well as for modulating the growth and pathfinding of axon tracts. In addition, they also mediate the functional maturation of axons by promoting their interactions with myelinating cells at the nodal, paranodal and juxtaparanodal regions. Such interactions also mediate differential ionic channels (both Na + and K + ) distribution, which is of critical relevance in the generation of the peak-shaped action potential. Indeed, thanks to their interactions with Ankyrin G, Na + channels map within the nodal regions, where they drive axonal depolarization. However, no ionic channels are found in the flanking Contactin1-containing paranodal regions, where CNTN1 interactions with Caspr1 and with the Ig superfamily component Neurofascin 155 in cis and in trans, respectively, build a molecular barrier between the node and the juxtaparanode. In this region K + channels are clustered, depending upon molecular interactions with Contactin 2 and with Caspr2. In addition to these functions, the Contactins appear to have also a role in degenerative and inflammatory

  16. AnchorDock: Blind and Flexible Anchor-Driven Peptide Docking.

    Science.gov (United States)

    Ben-Shimon, Avraham; Niv, Masha Y

    2015-05-05

    The huge conformational space stemming from the inherent flexibility of peptides is among the main obstacles to successful and efficient computational modeling of protein-peptide interactions. Current peptide docking methods typically overcome this challenge using prior knowledge from the structure of the complex. Here we introduce AnchorDock, a peptide docking approach, which automatically targets the docking search to the most relevant parts of the conformational space. This is done by precomputing the free peptide's structure and by computationally identifying anchoring spots on the protein surface. Next, a free peptide conformation undergoes anchor-driven simulated annealing molecular dynamics simulations around the predicted anchoring spots. In the challenging task of a completely blind docking test, AnchorDock produced exceptionally good results (backbone root-mean-square deviation ≤ 2.2Å, rank ≤15) for 10 of 13 unbound cases tested. The impressive performance of AnchorDock supports a molecular recognition pathway that is driven via pre-existing local structural elements. Copyright © 2015 Elsevier Ltd. All rights reserved.

  17. Bulk chirality effect for symmetric bistable switching of liquid crystals on topologically self-patterned degenerate anchoring surface.

    Science.gov (United States)

    Park, Min-Kyu; Joo, Kyung-Il; Kim, Hak-Rin

    2017-06-26

    We demonstrate a bistable switching liquid crystal (LC) mode utilizing a topologically self-structured dual-groove surface for degenerated easy axes of LC anchoring. In our study, the effect of the bulk elastic distortion of the LC directors on the bistable anchoring surface is theoretically analyzed for balanced bistable states based on a free energy diagram. By adjusting bulk LC chirality, we developed ideally symmetric and stable bistable anchoring and switching properties, which can be driven by a low in-plane pulsed field of about 0.7 V/µm. The fabricated device has a contrast ratio of 196:1.

  18. GPI-repetitive control for linear systems with parameter uncertainty / variation

    Directory of Open Access Journals (Sweden)

    John A. Cortés-Romero

    2015-01-01

    Full Text Available Robust repetitive control problems for uncertain linear systems have been considered by different approaches. This article proposes the use of Repetitive Control and Generalized Proportional Integral (GPI Control in a complementary fashion. The conditioning and coupling of these techniques has been done in a time discrete context. Repetitive control is a control technique, based on the internal model principle, which yields perfect asymptotic tracking and rejection of periodic signals. On the other hand, GPI control is established as a robust linear control system design technique that is able to reject structured time polynomial additive perturbation, in particular, parameter uncertainty that can be locally approximated by time polynomial signal. GPI control provides a suitable stability and robustness conditions for the proper Repetitive Control operation. A stability analysis is presented under the frequency response framework using plant samples for different parameter uncertainty conditions. We carry out some comparative stability analysis with other complementary control approaches that has been effective for this kind of task, enhancing a better robustness and an improved performance for the GPI case. Illustrative simulation examples are presented which validate the proposed approach.

  19. Increased infectivity of anchorless mouse scrapie prions in transgenic mice overexpressing human prion protein.

    Science.gov (United States)

    Race, Brent; Phillips, Katie; Meade-White, Kimberly; Striebel, James; Chesebro, Bruce

    2015-06-01

    Prion protein (PrP) is found in all mammals, mostly as a glycoprotein anchored to the plasma membrane by a C-terminal glycosylphosphatidylinositol (GPI) linkage. Following prion infection, host protease-sensitive prion protein (PrPsen or PrPC) is converted into an abnormal, disease-associated, protease-resistant form (PrPres). Biochemical characteristics, such as the PrP amino acid sequence, and posttranslational modifications, such as glycosylation and GPI anchoring, can affect the transmissibility of prions as well as the biochemical properties of the PrPres generated. Previous in vivo studies on the effects of GPI anchoring on prion infectivity have not examined cross-species transmission. In this study, we tested the effect of lack of GPI anchoring on a species barrier model using mice expressing human PrP. In this model, anchorless 22L prions derived from tg44 mice were more infectious than 22L prions derived from C57BL/10 mice when tested in tg66 transgenic mice, which expressed wild-type anchored human PrP at 8- to 16-fold above normal. Thus, the lack of the GPI anchor on the PrPres from tg44 mice appeared to reduce the effect of the mouse-human PrP species barrier. In contrast, neither source of prions induced disease in tgRM transgenic mice, which expressed human PrP at 2- to 4-fold above normal. Prion protein (PrP) is found in all mammals, usually attached to cells by an anchor molecule called GPI. Following prion infection, PrP is converted into a disease-associated form (PrPres). While most prion diseases are species specific, this finding is not consistent, and species barriers differ in strength. The amino acid sequence of PrP varies among species, and this variability affects prion species barriers. However, other PrP modifications, including glycosylation and GPI anchoring, may also influence cross-species infectivity. We studied the effect of PrP GPI anchoring using a mouse-to-human species barrier model. Experiments showed that prions produced by

  20. Distinctive and Complementary MS2 Fragmentation Characteristics for Identification of Sulfated Sialylated N-Glycopeptides by nanoLC-MS/MS Workflow

    Science.gov (United States)

    Kuo, Chu-Wei; Guu, Shih-Yun; Khoo, Kay-Hooi

    2018-04-01

    High sensitivity identification of sulfated glycans carried on specific sites of glycoproteins is an important requisite for investigation of molecular recognition events involved in diverse biological processes. However, aiming for resolving site-specific glycosylation of sulfated glycopeptides by direct LC-MS2 sequencing is technically most challenging. Other than the usual limiting factors such as lower abundance and ionization efficiency compared to analysis of non-glycosylated peptides, confident identification of sulfated glycopeptides among the more abundant non-sulfated glycopeptides requires additional considerations in the selective enrichment and detection strategies. Metal oxide has been applied to enrich phosphopeptides and sialylated glycopeptides, but its use to capture sulfated glycopeptides has not been investigated. Likewise, various complementary MS2 fragmentation modes have yet to be tested against sialylated and non-sialylated sulfoglycopeptides due to limited appropriate sample availability. In this study, we have investigated the feasibility of sequencing tryptic sulfated N-glycopeptide and its MS2 fragmentation characteristics by first optimizing the enrichment methods to allow efficient LC-MS detection and MS2 analysis by a combination of CID, HCD, ETD, and EThcD on hybrid and tribrid Orbitrap instruments. Characteristic sulfated glyco-oxonium ions and direct loss of sulfite from precursors were detected as evidences of sulfate modification. It is anticipated that the technical advances demonstrated in this study would allow a feasible extension of our sulfoglycomic analysis to sulfoglycoproteomics. [Figure not available: see fulltext.

  1. Targeting aberrant sialylation in cancer cells using a fluorinated sialic acid analog impairs adhesion, migration, and in vivo tumor growth

    NARCIS (Netherlands)

    Bull, C.; Boltje, T.J.; Wassink, M.; Graaf, A.M.A. de; Delft, F.L. van; Brok, M.H.M.G.M. den; Adema, G.J.

    2013-01-01

    Cancer cells decorate their surface with a dense layer of sialylated glycans by upregulating the expression of sialyltransferases and other glycogenes. Although sialic acids play a vital role in many biologic processes, hypersialylation in particular has been shown to contribute to cancer cell

  2. Enzyme catalysed production of sialylated human milk oligosaccharides and galactooligosaccharides by Trypanosoma cruzi trans-sialidase

    DEFF Research Database (Denmark)

    Holck, Jesper; Larsen, Dorte Møller; Michalak, Malwina

    2014-01-01

    Bifidobacterium strains in single culture fermentations. The trans-sialidase also catalysed the transfer of sialic acid from CGMP to galacto-oligosaccharides (GOS) and to the human milk oligosaccharide (HMO) backbone lacto-N-tetraose (LNT) to produce 3′-sialyl-GOS, including doubly sialylated GOS products, and 3...

  3. Asparagine-linked oligosaccharides on lutropin, follitropin, and thyrotropin: distributions of sulfated and sialylated oligosaccharides on bovine, ovine, and human pituitary glycoprotein hormones

    International Nuclear Information System (INIS)

    Green, E.D.; Baenziger, J.U.

    1988-01-01

    The asparagine-linked oligosaccharides on the pituitary glycoprotein hormones lutropin (LH), follitropin (FSH), and thyrotropin (TSH) consist of a heterogeneous array of neutral, sulfated, sialylated, and sulfated/sialylated structures. In this study, the authors determined the relative quantities of the various asparagine-linked oligosaccharides on LH, FSH, and TSH from these three animal species. The proportions of sulfated versus sialylated oligosaccharides varied markedly among the different hormones. Both hormone- and animal species-specific differences in the types and distributions of sulfated, sialylated, and sulfated/sialylated structures were evident. In particular, LH and FSH, which are synthesized in the same pituitary cell and bear α-subunits with the identical amino acid sequence, contained significantly different distributions of sulfated and sialylated oligosaccharides. For all three animal species, the ratio of sialylated to sulfated oligosaccharides differed by >10-fold for LH and FSH, with sulfated structures dominating on LH and sialylated structures on FSH. Sialylated oligosaccharides were also heterogeneous with respect to sialic acid linkage (α2,3 versus α2,6). The differences in oligosaccharide structures among the various pituitary glycoprotein hormones as well as among the various glycosylation sites within a single hormone support the hypothesis that glycosylation may serve important functional roles in the expression and/or regulation of hormone bioactivity

  4. Sialylation of Porphyromonas gingivalis LPS and its effect on bacterial-host interactions.

    Science.gov (United States)

    Zaric, Svetislav S; Lappin, Mark J; Fulton, Catherine R; Lundy, Fionnuala T; Coulter, Wilson A; Irwin, Christopher R

    2017-04-01

    Porphyromonas gingivalis produces different LPS isoforms with significant structural variations of their lipid A and O-antigen moieties that can affect its pro-inflammatory and bone-resorbing potential. We show here, for the first time, that P. gingivalis LPS isolated from W83 strain is highly sialylated and possesses significantly reduced inflammatory potential compared with less sialylated ATCC 33277 strain LPS. Nevertheless, the reduction in the endotoxin activity is not mediated by the presence of sialic acid LPS moieties as the sialic acid-free LPS produced by the mutant W83 strain exhibits a similar inflammatory potential to the wild type strain. Furthermore, our findings suggest that the interaction between the sialic acid LPS moieties and the inhibitory CD33 receptor is prevented by endogenously expressed sialic acid on the surface of THP-1 cells that cannot be out-competed by sialic acid containing P. gingivalis LPS. The present study also highlights the importance of endogenous sialic acid as a 'self-associated molecular pattern' and CD33 receptors in modulation of innate immune response as human gingival fibroblasts, which do not express CD33 receptors, and desialylated THP-1 cells have both been found to have much higher spontaneous IL-8 production than naïve THP-1 cells.

  5. Anchoring of alkyl chain molecules on oxide surface using silicon alkoxide

    Energy Technology Data Exchange (ETDEWEB)

    Narita, Ayumi, E-mail: narita.ayumi@jaea.go.jp [Quantum Beam Science Directorate, Japan Atomic Energy Agency, Tokai-mura, Naka-gun, Ibaraki-ken 319-1195 (Japan); Graduate School of Science and Engineering, Ibaraki University, Bunnkyo, Mito-shi, Ibaraki-ken 310-8512 (Japan); Baba, Yuji; Sekiguchi, Tetsuhiro; Shimoyama, Iwao; Hirao, Norie [Quantum Beam Science Directorate, Japan Atomic Energy Agency, Tokai-mura, Naka-gun, Ibaraki-ken 319-1195 (Japan); Yaita, Tsuyoshi [Quantum Beam Science Directorate, Japan Atomic Energy Agency, Tokai-mura, Naka-gun, Ibaraki-ken 319-1195 (Japan); Graduate School of Science and Engineering, Ibaraki University, Bunnkyo, Mito-shi, Ibaraki-ken 310-8512 (Japan)

    2012-01-01

    Chemical states of the interfaces between octadecyl-triethoxy-silane (ODTS) molecules and sapphire surface were measured by X-ray photoelectron spectroscopy (XPS) and near edge X-ray absorption fine structure (NEXAFS) using synchrotron soft X-rays. The nearly self-assembled monolayer of ODTS was formed on the sapphire surface. For XPS and NEXAFS measurements, it was elucidated that the chemical bond between silicon alkoxide in ODTS and the surface was formed, and the alkane chain of ODTS locates upper side on the surface. As a result, it was elucidated that the silicon alkoxide is a good anchor for the immobilization of organic molecules on oxides.

  6. ST6GalNAc-I controls expression of sialyl-Tn antigen in gastrointestinal tissues

    DEFF Research Database (Denmark)

    Marcos, Nuno T; Bennett, Eric Paul; Gomes, Joana

    2011-01-01

    -Tn biosynthesis. We developed novel monoclonal antibodies specific for ST6GalNAc-I and evaluated its expression in gastrointestinal tissues. ST6GalNAc-I was detected in normal colon mucosa co-localized with O-acetylated sialyl-Tn. Expression was largely unaltered in colorectal adenocarcinomas. In contrast, we......NAc-I as the major enzyme controlling the expression of cancer-associated sialyl-Tn antigen in gastrointestinal tissues....

  7. Quantitative and qualitative characterization of human cancer-associated serum glycoprotein antigens expressing epitopes consisting of sialyl or sialyl-fucosyl type 1 chain.

    Science.gov (United States)

    Kannagi, R; Kitahara, A; Itai, S; Zenita, K; Shigeta, K; Tachikawa, T; Noda, A; Hirano, H; Abe, M; Shin, S

    1988-07-01

    The levels of carbohydrate antigens having epitopes consisting of type 1 chain (R----Gal beta 1----GlcNAc beta 1----3Gal beta 1----R) in the sera of patients with various malignant and nonmalignant disorders have been investigated with the use of three monoclonal antibodies, N-19-9, FH-7, and FH-9. Serum levels of 2----3 sialylated Lea antigen and 2----6 sialylated Lea antigen, defined respectively by antibodies N-19-9 and FH-7, were found to be frequently high in patients with cancer of the digestive system, particularly pancreatic cancer. High levels of 2----3,2----6 disialylated Lc4 antigen, defined by antibody FH-9, were less frequent in cancer patients when compared with the other two antigens. In patients with nonmalignant disorders, especially renal and autoimmune diseases, serum levels of the two type 1 chain antigens defined by FH-7 and FH-9 were more frequently high than that defined by N-19-9. Molecular weights and other general biochemical characteristics of serum mucin carrying the type 1 chain determinants were not significantly different in cancer patients as compared with patients with nonmalignant disorders. However, the degree of glycosylation of the antigen, as assessed by its solubility in perchloric acid, showed significant differences; i.e., the mucin antigen carrying 2----6 sialylated Lea determinant in the sera of patients with nonmalignant disorders had the highest carbohydrate/protein ratio, followed by the mucin carrying the same determinant in the sera of cancer patients. Mucin antigen carrying 2----3 sialylated Lea antigen or 2----3, 2----6 disialylated Lc4 antigen in cancer patients had the lowest carbohydrate/protein ratio among the four groups tested. Thus, the carbohydrate/protein ratio in the type 1 chain mucin antigens in sera of normal subjects is higher than that in sera of cancer patients (P less than 0.05). This finding is in contrast to previous findings on the mucin antigens carrying the type 2 chain determinant (R. Kannagi

  8. Phosphatidylinositol-glycan-phospholipase D is involved in neurodegeneration in prion disease.

    Directory of Open Access Journals (Sweden)

    Jae-Kwang Jin

    Full Text Available PrPSc is formed from a normal glycosylphosphatidylinositol (GPI-anchored prion protein (PrPC by a posttranslational modification. Most GPI-anchored proteins have been shown to be cleaved by GPI phospholipases. Recently, GPI-phospholipase D (GPI-PLD was shown to be a strictly specific enzyme for GPI anchors. To investigate the involvement of GPI-PLD in the processes of neurodegeneration in prion diseases, we examined the mRNA and protein expression levels of GPI-PLD in the brains of a prion animal model (scrapie, and in both the brains and cerebrospinal fluids (CSF of sporadic and familial Creutzfeldt-Jakob disease (CJD patients. We found that compared with controls, the expression of GPI-PLD was dramatically down-regulated in the brains of scrapie-infected mice, especially in the caveolin-enriched membrane fractions. Interestingly, the observed decrease in GPI-PLD expression levels began at the same time that PrPSc began to accumulate in the infected brains and this decrease was also observed in both the brain and CSF of CJD patients; however, no differences in expression were observed in either the brains or CSF specimens from Alzheimer's disease patients. Taken together, these results suggest that the down-regulation of GPI-PLD protein may be involved in prion propagation in the brains of prion diseases.

  9. A Pasteurella multocida sialyltransferase displaying dual trans-sialidase activities for production of 3′-sialyl and 6′-sialyl glycans

    DEFF Research Database (Denmark)

    Guo, Yao; Jers, Carsten; Meyer, Anne S.

    2014-01-01

    /Kmvalue for the enzyme using 3-sialyllactose as the donor for 6-sialyllactose synthesis at pH 5.4 and 40◦Cwas determined to be 23.22 ± 0.7 M−1s−1. Moreover, the enzyme was capable of catalyzing the synthesisof both 3- and 6-sialylated galactooligosaccharides, when galactooligosaccharides served as acceptors....

  10. Covalent glycoinositolphospholipid (GPI binding to hemoglobin is associated with insulin-activation of erythrocyte membrane protease

    Directory of Open Access Journals (Sweden)

    VESNA NIKETIC

    2004-05-01

    Full Text Available Recently, it was demonstrated that prolonged hyperinsulinism associated with hypoglycemia, both in vivo and in vitro, caused covalent glycoinositolphospholipid (GPI binding to the C termini of both hemoglobin b-chains, which resulted in the formation of a novel, hitherto unrecognized, minor hemoglobin fraction (GPI-Hb (Niketic et al., Biochem. Biophys. Res. Commun. 239 (1997 435. In this study it was demonstrated that exposure of erythrocyte membranes to insulin causes the activation of membrane protease as well as that the formation of GPI-Hb parallels its activity. It is suggested that the insulin-activated protease is able to catalyze, albeit slowly, the transpeptidation, i.e., the replacement of the carboxy-terminal amino acid(s residues of the Hb b-chains with GPI as an exogenous nucleophile. To our knowledge the present results show for the first time that insulin stimulates protease activity in erythrocyte membranes, as well as that insulin-activated protease may be involved in post-translational GPI binding to proteins.

  11. A cell-surface-anchored ratiometric i-motif sensor for extracellular pH detection.

    Science.gov (United States)

    Ying, Le; Xie, Nuli; Yang, Yanjing; Yang, Xiaohai; Zhou, Qifeng; Yin, Bincheng; Huang, Jin; Wang, Kemin

    2016-06-14

    A FRET-based sensor is anchored on the cell surface through streptavidin-biotin interactions. Due to the excellent properties of the pH-sensitive i-motif structure, the sensor can detect extracellular pH with high sensitivity and excellent reversibility.

  12. Neuroimmunophilin GPI-1046 reduces ethanol consumption in part through activation of GLT1 in alcohol-preferring rats.

    Science.gov (United States)

    Sari, Y; Sreemantula, S N

    2012-12-27

    We have previously shown that ceftriaxone, β-lactam antibiotic known to upregulate glutamate transporter 1 (GLT1), reduced ethanol intake in alcohol-preferring (P) rats. GLT1 is a glial glutamate transporter that regulates the majority of extracellular glutamate uptake. We tested in this study the effects of neuroimmunophilin GPI-1046 (3-(3-pyridyl)-1-propyl (2S)-1-(3,3-dimethyl-1,2-dioxopentyl)-2-pyrrolidinecarboxylate), known also to upregulate GLT1 expression, in ethanol intake in P rats. Male P rats had concurrent access to free choice of 15% and 30% ethanol, water, and food for five weeks. On Week 6, P rats continued in this drinking and food regimen and they were administered either 10 or 20mg/kg GPI-1046 (i.p.), or a vehicle for five consecutive days. Body weight, ethanol intake, and water consumption were measured daily for 8 days starting on Day 1 of GPI-1046 or vehicle i.p. injections. We have also tested the effect of GPI-1046 (20mg/kg) on daily sucrose (10%) intake. The data revealed significant dose-dependent effects in the reduction of ethanol intake starting 48 h after the first treatment with GPI-1046 throughout treatment and post-treatment periods. There were also dose-dependent increases in water intake. However, GPI-1046 treatment did not affect the body weight of all animals nor sucrose intake. Importantly, GPI-1046 (20mg/kg) increased GLT1 level compared to all groups in nucleus accumbens core (NAc-core). Alternatively, GPI-1046 (10mg/kg) upregulated GLT1 level in NAc-core compared to vehicle (ethanol naïve) group. Moreover, both doses of GPI-1046 increased significantly GLT1 level in the prefrontal cortex (PFC) compared to ethanol naïve vehicle group. GPI-1046 (20mg/kg) increased GLT1 level in PFC compared to naïve control group that was exposed to water and food only. These findings demonstrated that neuroimmunophilin GPI-1046 attenuates ethanol intake in part through the upregulation of GLT1 in PFC and NAc-core. Copyright © 2012 IBRO

  13. LpMab-12 Established by CasMab Technology Specifically Detects Sialylated O-Glycan on Thr52 of Platelet Aggregation-Stimulating Domain of Human Podoplanin.

    Directory of Open Access Journals (Sweden)

    Yukinari Kato

    Full Text Available Podoplanin (PDPN, also known as Aggrus, possesses three tandem repeat of platelet aggregation-stimulating (PLAG domains in its N-terminus. Among the PLAG domains, sialylated O-glycan on Thr52 of PLAG3 is essential for the binding to C-type lectin-like receptor-2 (CLEC-2 and the platelet-aggregating activity of human PDPN (hPDPN. Although various anti-hPDPN monoclonal antibodies (mAbs have been generated, no specific mAb has been reported to target the epitope containing glycosylated Thr52. We recently established CasMab technology to develop mAbs against glycosylated membrane proteins. Herein, we report the development of a novel anti-glycopeptide mAb (GpMab, LpMab-12. LpMab-12 detected endogenous hPDPN by flow cytometry. Immunohistochemical analyses also showed that hPDPN-expressing lymphatic endothelial and cancer cells were clearly labeled by LpMab-12. The minimal epitope of LpMab-12 was identified as Asp49-Pro53 of hPDPN. Furthermore, LpMab-12 reacted with the synthetic glycopeptide of hPDPN, corresponding to 38-54 amino acids (hpp3854: 38-EGGVAMPGAEDDVVTPG-54, which carries α2-6 sialylated N-acetyl-D-galactosamine (GalNAc on Thr52. LpMab-12 did not recognize non-sialylated GalNAc-attached glycopeptide, indicating that sialylated GalNAc on Thr52 is necessary for the binding of LpMab-12 to hPDPN. Thus, LpMab-12 could serve as a new diagnostic tool for determining whether hPDPN possesses the sialylation on Thr52, a site-specific post-translational modification critical for the hPDPN association with CLEC-2.

  14. Analysis and functional consequences of increased Fab-sialylation of intravenous immunoglobulin (IVIG) after lectin fractionation.

    Science.gov (United States)

    Käsermann, Fabian; Boerema, David J; Rüegsegger, Monika; Hofmann, Andreas; Wymann, Sandra; Zuercher, Adrian W; Miescher, Sylvia

    2012-01-01

    It has been proposed that the anti-inflammatory effects of intravenous immunoglobulin (IVIG) might be due to the small fraction of Fc-sialylated IgG. In this study we biochemically and functionally characterized sialic acid-enriched IgG obtained by Sambucus nigra agglutinin (SNA) lectin fractionation. Two main IgG fractions isolated by elution with lactose (E1) or acidified lactose (E2) were analyzed for total IgG, F(ab')(2) and Fc-specific sialic acid content, their pattern of specific antibodies and anti-inflammatory potential in a human in vitro inflammation system based on LPS- or PHA-stimulated whole blood. HPLC and LC-MS testing revealed an increase of sialylated IgG in E1 and more substantially in the E2 fraction. Significantly, the increased amount of sialic acid residues was primarily found in the Fab region whereas only a minor increase was observed in the Fc region. This indicates preferential binding of the Fab sialic acid to SNA. ELISA analyses of a representative range of pathogen and auto-antigens indicated a skewed antibody pattern of the sialylated IVIG fractions. Finally, the E2 fraction exerted a more profound anti-inflammatory effect compared to E1 or IVIG, evidenced by reduced CD54 expression on monocytes and reduced secretion of MCP-1 (CCL2); again these effects were Fab- but not Fc-dependent. Our results show that SNA fractionation of IVIG yields a minor fraction (approx. 10%) of highly sialylated IgG, wherein the sialic acid is mainly found in the Fab region. The tested anti-inflammatory activity was associated with Fab not Fc sialylation.

  15. Analysis and functional consequences of increased Fab-sialylation of intravenous immunoglobulin (IVIG after lectin fractionation.

    Directory of Open Access Journals (Sweden)

    Fabian Käsermann

    Full Text Available It has been proposed that the anti-inflammatory effects of intravenous immunoglobulin (IVIG might be due to the small fraction of Fc-sialylated IgG. In this study we biochemically and functionally characterized sialic acid-enriched IgG obtained by Sambucus nigra agglutinin (SNA lectin fractionation. Two main IgG fractions isolated by elution with lactose (E1 or acidified lactose (E2 were analyzed for total IgG, F(ab'(2 and Fc-specific sialic acid content, their pattern of specific antibodies and anti-inflammatory potential in a human in vitro inflammation system based on LPS- or PHA-stimulated whole blood. HPLC and LC-MS testing revealed an increase of sialylated IgG in E1 and more substantially in the E2 fraction. Significantly, the increased amount of sialic acid residues was primarily found in the Fab region whereas only a minor increase was observed in the Fc region. This indicates preferential binding of the Fab sialic acid to SNA. ELISA analyses of a representative range of pathogen and auto-antigens indicated a skewed antibody pattern of the sialylated IVIG fractions. Finally, the E2 fraction exerted a more profound anti-inflammatory effect compared to E1 or IVIG, evidenced by reduced CD54 expression on monocytes and reduced secretion of MCP-1 (CCL2; again these effects were Fab- but not Fc-dependent. Our results show that SNA fractionation of IVIG yields a minor fraction (approx. 10% of highly sialylated IgG, wherein the sialic acid is mainly found in the Fab region. The tested anti-inflammatory activity was associated with Fab not Fc sialylation.

  16. New insights into the organization of plasma membrane and its role in signal transduction.

    Science.gov (United States)

    Suzuki, Kenichi G N

    2015-01-01

    Plasma membranes have heterogeneous structures for efficient signal transduction, required to perform cell functions. Recent evidence indicates that the heterogeneous structures are produced by (1) compartmentalization by actin-based membrane skeleton, (2) raft domains, (3) receptor-receptor interactions, and (4) the binding of receptors to cytoskeletal proteins. This chapter provides an overview of recent studies on diffusion, clustering, raft association, actin binding, and signal transduction of membrane receptors, especially glycosylphosphatidylinositol (GPI)-anchored receptors. Studies on diffusion of GPI-anchored receptors suggest that rafts may be small and/or short-lived in plasma membranes. In steady state conditions, GPI-anchored receptors form transient homodimers, which may represent the "standby state" for the stable homodimers and oligomers upon ligation. Furthermore, It is proposed that upon ligation, the binding of GPI-anchored receptor clusters to cytoskeletal actin filaments produces a platform for downstream signaling, and that the pulse-like signaling easily maintains the stability of the overall signaling activity. Copyright © 2015 Elsevier Inc. All rights reserved.

  17. Adsorption phenomena and anchoring energy in nematic liquid crystals

    CERN Document Server

    Barbero, Giovanni

    2005-01-01

    Despite the large quantity of phenomenological information concerning the bulk properties of nematic phase liquid crystals, little is understood about the origin of the surface energy, particularly the surface, interfacial, and anchoring properties of liquid crystals that affect the performance of liquid crystal devices. Self-contained and unique, Adsorption Phenomena and Anchoring Energy in Nematic Liquid Crystals provides an account of new and established results spanning three decades of research into the problems of anchoring energy and adsorption phenomena in liquid crystals.The book contains a detailed discussion of the origin and possible sources of anchoring energy in nematic liquid crystals, emphasizing the dielectric contribution to the anchoring energy in particular. Beginning with fundamental surface and anchoring properties of liquid crystals and the definition of the nematic phase, the authors explain how selective ion adsorption, dielectric energy density, thickness dependence, and bias voltage...

  18. Induction of rat alkaline phosphatase isozymes bearing a glycan-phosphatidylinositol anchor modified by in vivo treatment with a benzimidazole derivative linked to ethylbenzene.

    Science.gov (United States)

    Harada, T; Koyama, I; Sato, K; Komoda, T

    2000-10-01

    Serum alkaline phosphatase (ALP) is detected in soluble-form as a result of translocation from the membrane site by cleavage at the glycosyl-phosphatidylinositol moiety (GPI anchor). It is known that membrane-bound ALP (mALP) can be detected in serum in certain pathological and physiological conditions, and that it can be solubilized in vitro to soluble-ALP (sALP) by phosphatidylinositol-specific phospholipase C (PIPLC), phospholipase D, bile salt, detergent, etc. We observed a marked increase in ALP activity in the serum of rats given a benzimidazole derivative by gavage, and detected it as slow-migrating ALPs (SM-ALPs), which were mALP-like but resistant to PIPLC and n-butanol treatment on disc PAGE. On the other hand, ficin treatment made SM-ALPs shift to the sALP position. The molecular size of the SM-ALPs was smaller than that of sALP on sodium dodecyl sulphide-polyacrylamide slab-gel electrophoresis (SDS-PAGE), and immunoreactivity revealed the intestinal type. SM-ALPs were also detected in the duodenum and jejunum. The main sugar chain structure of SM-ALPs was the biantennary complex-type, which was coincided with intestinal sALP sugar chain. These results suggest that intestinal ALPs induced by the benzimidazole derivative were modified in their C-terminus or GPI anchor region and modification of this region may also participate in translocation into the bloodstream.

  19. Position and Orientation Control of a Photo- and Electrochromic Dithienylethene Using a Tripodal Anchor on Gold Surfaces

    NARCIS (Netherlands)

    Pijper, Thomas C.; Ivashenko, Oleksii; Walko, Martin; Rudolf, Petra; Browne, Wesley R.; Feringa, Ben L.

    2015-01-01

    A tripodal system for anchoring photochromic dithienylethenes on gold surfaces is reported. The self-assembled monolayers of a tripod-functionalized dithienylethene were characterized by cyclic voltammetry, surface-enhanced Raman spectroscopy (SERS), and X-ray photoelectron spectroscopy (XPS). These

  20. Phosphorylation of varicella-zoster virus glycoprotein gpI by mammalian casein kinase II and casein kinase I

    International Nuclear Information System (INIS)

    Grose, C.; Jackson, W.; Traugh, J.A.

    1989-01-01

    Varicella-zoster virus (VZV) glycoprotein gpI is the predominant viral glycoprotein within the plasma membranes of infected cells. This viral glycoprotein is phosphorylated on its polypeptide backbone during biosynthesis. In this report, the authors investigated the protein kinases which participate in the phosphorylation events. Under in vivo conditions, VZV gpI was phosphorylated on its serine and threonine residues by protein kinases present within lysates of either VZV-infected or uninfected cells. Because this activity was diminished by heparin, a known inhibitor of casein kinase II, isolated gpI was incubated with purified casein kinase II and shown to be phosphorylated in an in vitro assay containing [γ- 32 P]ATP. The same glycoprotein was phosphorylated when [ 32 P]GTP was substituted for [ 32 P]ATP in the protein kinase assay. They also tested whether VZV gpI was phosphorylated by two other ubiquitous mammalian protein kinases--casein kinase I and cyclic AMP-dependent kinase--and found that only casein kinase I modified gpI. When the predicted 623-amino-acid sequence of gpI was examined, two phosphorylation sites known to be optimal for casein kinase II were observed. In summary, this study showed that VZV gpI was phosphorylated by each of two mammalian protein kinases (casein kinase I and casein kinase II) and that potential serine-threonine phosphorylation sites for each of these two kinases were present in the viral glycoprotein

  1. A cell-surface-anchored ratiometric fluorescent probe for extracellular pH sensing.

    Science.gov (United States)

    Ke, Guoliang; Zhu, Zhi; Wang, Wei; Zou, Yuan; Guan, Zhichao; Jia, Shasha; Zhang, Huimin; Wu, Xuemeng; Yang, Chaoyong James

    2014-09-10

    Accurate sensing of the extracellular pH is a very important yet challenging task in biological and clinical applications. This paper describes the development of an amphiphilic lipid-DNA molecule as a simple yet useful cell-surface-anchored ratiometric fluorescent probe for extracellular pH sensing. The lipid-DNA probe, which consists of a hydrophobic diacyllipid tail and a hydrophilic DNA strand, is modified with two fluorescent dyes; one is pH-sensitive as pH indicator and the other is pH-insensitive as an internal reference. The lipid-DNA probe showed sensitive and reversible response to pH change in the range of 6.0-8.0, which is suitable for most extracellular studies. In addition, based on simple hydrophobic interactions with the cell membrane, the lipid-DNA probe can be easily anchored on the cell surface with negligible cytotoxicity, excellent stability, and unique ratiometric readout, thus ensuring its accurate sensing of extracellular pH. Finally, this lipid-DNA-based ratiometric pH indicator was successfully used for extracellular pH sensing of cells in 3D culture environment, demonstrating the potential applications of the sensor in biological and medical studies.

  2. Microgravity Drill and Anchor System

    Science.gov (United States)

    Parness, Aaron; Frost, Matthew A.; King, Jonathan P.

    2013-01-01

    This work is a method to drill into a rock surface regardless of the gravitational field or orientation. The required weight-on-bit (WOB) is supplied by a self-contained anchoring mechanism. The system includes a rotary percussive coring drill, forming a complete sampling instrument usable by robot or human. This method of in situ sample acquisition using micro - spine anchoring technology enables several NASA mission concepts not currently possible with existing technology, including sampling from consolidated rock on asteroids, providing a bolt network for astronauts visiting a near-Earth asteroid, and sampling from the ceilings or vertical walls of lava tubes and cliff faces on Mars. One of the most fundamental parameters of drilling is the WOB; essentially, the load applied to the bit that allows it to cut, creating a reaction force normal to the surface. In every drilling application, there is a minimum WOB that must be maintained for the system to function properly. In microgravity (asteroids and comets), even a small WOB could not be supported conventionally by the weight of the robot or astronaut. An anchoring mechanism would be needed to resist the reactions, or the robot or astronaut would push themselves off the surface and into space. The ability of the system to anchor itself to a surface creates potential applications that reach beyond use in low gravity. The use of these anchoring mechanisms as end effectors on climbing robots has the potential of vastly expanding the scope of what is considered accessible terrain. Further, because the drill is supported by its own anchor rather than by a robotic arm, the workspace is not constrained by the reach of such an arm. Yet, if the drill is on a robotic arm, it has the benefit of not reflecting the forces of drilling back to the arm s joints. Combining the drill with the anchoring feet will create a highly mobile, highly stable, and highly reliable system. The drilling system s anchor uses hundreds of

  3. Adsorption of non-ionic ABC triblock copolymers: Surface modification of TiO2 suspensions in aqueous and non-aqueous medium

    Science.gov (United States)

    Lerch, Jean-Philippe; Atanase, Leonard Ionut; Riess, Gérard

    2017-10-01

    A series of non-ionic ABC triblock copolymers, such as poly(butadiene)-b-poly(2-vinylpyrridine)-b-poly(ethylene oxide) (PB-P2VP-PEO) were synthesized by sequential anionic polymerizations. For these copolymers comprising an organo-soluble PB and a water-soluble PEO block, their P2VP middle block has been selected for its anchoring capacity on solid surfaces. The adsorption isotherms on TiO2 were obtained in heptane and in aqueous medium, as selective solvents. In both of these cases, the P2VP middle block provides the surface anchoring, whereas PB and PEO sequences are acting as stabilizing moieties in heptane and water respectively. By extension to ABC triblock copolymers of the scaling theory developed for diblock copolymers, the density of adsorbed chains could be correlated with the molecular characteristics of the PB-P2VP-PEO triblock copolymers. From a practical point a view, it could be demonstrated that these copolymers are efficient dispersing agents for the TiO2 pigments in both aqueous and non-aqueous medium.

  4. Revealing the structure and dust content of debris disks on solar systems scales with GPI

    Science.gov (United States)

    Duchene, Gaspard; Fitzgerald, Michael P.; Kalas, Paul; Graham, James R.; Arriaga, Pauline; Bruzzone, Sebastian; Chen, Christine; Dawson, Rebekah Ilene; Dong, Ruobing; Draper, Zachary; Esposito, Thomas; Follette, Katherine; Hung, Li-Wei; Lawler, Samantha; Metchev, Stanimir; Millar-Blanchaer, Max; Murray-Clay, Ruth; Perrin, Marshall D.; Rameau, Julien; Wang, Jason; Wolff, Schuyler; Macintosh, Bruce; GPIES Team

    2016-01-01

    High contrast scattered light images offer the best prospect to assess the detailed geometry and structure of dusty debris disks. In turn, such images can yield profound insight on the architecture of the underlying planetary system as dust grains respond to the gravitational pull of planetary bodies. A new generation of extreme adaptive optics systems now enables an unprecedented exploration of circumstellar disks on solar system scales. Here we review the new science derived from over a dozen debris disks imaged with the Gemini Planet Imager (GPI) as part of the GPI Exoplanet Survey (GPIES). In addition to its exquisite imaging capability, GPI's polarimetric mode provides invaluable insight on the dust content of each disk, in most cases for the very first time. These early results typically reveal narrow belts of material with evacuated regions roughly 50-100 AU in radius, subtle asymmetries in structure and high degree of linear polarization. We will provide an overview of the disk observations made during the GPIES campaign to date and will discuss in more detail some of the most remarkable systems.This work is supported by grants NSF AST-0909188, -1411868, -1413718; NASA NNX-15AD95G, -14AJ80G, -11AD21G; and the NExSS research network.

  5. Surface effects on magnetic Freedericksz transition in ferronematics with soft particle anchoring

    International Nuclear Information System (INIS)

    Bena, R.-E.; Petrescu, Emil

    2003-01-01

    The magnetic field-induced Freedericksz transition in a homeotropically aligned ferronematic (FN) in the case of weak anchoring molecules to the walls is studied. A correction to the Burylov-Raikher expression for the second-order transition threshold field is found. The possibility of a first-order transition is discussed in connection with the similar results for nematic liquid crystals. The saturation magnetic field is also obtained in terms of FN, surface and device parameters

  6. A novel mutation in PGAP2 gene causes developmental delay, intellectual disability, epilepsy and microcephaly in consanguineous Saudi family.

    Science.gov (United States)

    Naseer, Muhammad Imran; Rasool, Mahmood; Jan, Mohammed M; Chaudhary, Adeel G; Pushparaj, Peter Natesan; Abuzenadah, Adel M; Al-Qahtani, Mohammad H

    2016-12-15

    PGAP2 (Post-GPI Attachment to Proteins 2) gene is involved in lipid remodeling steps of Glycosylphosphatidylinositol (GPI)-anchor maturation. At the surface of the cell this gene is required for proper expression of GPI-anchored proteins. Hyperphosphatasia with mental retardation syndrome-3 is an autosomal recessive disorder usually characterized by severe mental retardation. Mutations in the PGAP2 gene cause hyperphosphatasia mental retardation syndrome-3. We have identified a large consanguineous family from Saudi origin segregating developmental delay, intellectual disability, epilepsy and microcephaly. Whole exome sequencing with 100× coverage was performed on two affected siblings of the family. Data analysis in the patient revealed a novel missense mutation c.191C>T in PGAP2 gene resulting in Alanine to Valine substitution (Ala64Val). The mutation was reconfirmed and validated by subsequent Sanger sequencing method. The mutation was ruled out in 100 unrelated healthy controls. We suggest that this pathogenic mutation disrupts the proper function of the gene proteins resulting in the disease state. Copyright © 2016 Elsevier B.V. All rights reserved.

  7. Electro-osmosis of nematic liquid crystals under weak anchoring and second-order surface effects

    Science.gov (United States)

    Poddar, Antarip; Dhar, Jayabrata; Chakraborty, Suman

    2017-07-01

    Advent of nematic liquid crystal flows has attracted renewed attention in view of microfluidic transport phenomena. Among various transport processes, electro-osmosis stands as one of the efficient flow actuation mechanisms through narrow confinements. In the present study, we explore the electrically actuated flow of an ordered nematic fluid with ionic inclusions, taking into account the influences from surface-induced elasticity and electrical double layer (EDL) phenomena. Toward this, we devise the coupled flow governing equations from fundamental free-energy analysis, considering the contributions from first- and second-order elastic, dielectric, flexoelectric, charged surface polarization, ionic and entropic energies. The present study focuses on the influence of surface charge and elasticity effects in the resulting linear electro-osmosis through a slit-type microchannel whose surfaces are chemically treated to display a homeotropic-type weak anchoring state. An optical periodic stripe configuration of the nematic director has been observed, especially for higher electric fields, wherein the Ericksen number for the dynamic study is restricted to the order of unity. Contrary to the isotropic electrolytes, the EDL potential in this case was found to be dependent on the external field strength. Through a systematic investigation, we brought out the fact that the wavelength of the oscillating patterns is dictated mainly by the external field, while the amplitude depends on most of the physical variables ranging from the anchoring strength and the flexoelectric coefficients to the surface charge density and electrical double layer thickness.

  8. Expression of human FcgammaRIIIa as a GPI-linked molecule on CHO cells to enable measurement of human IgG binding.

    Science.gov (United States)

    Armour, Kathryn L; Smith, Cheryl S; Clark, Michael R

    2010-03-31

    The efficacy of a therapeutic IgG molecule may be as dependent on the optimisation of the constant region to suit its intended indication as on the selection of its variable regions. A crucial effector function to be maximised or minimised is antibody-dependent cell-mediated cytotoxicity by natural killer cells. Traditional assays of ADCC activity suffer from considerable inter-donor and intra-donor variability, which makes the measurement of antibody binding to human FcgammaRIIIa, the key receptor for ADCC, an attractive alternative method of assessment. Here, we describe the development of cell lines and assays for this purpose. The transmembrane receptor, FcgammaRIIIa, requires co-expression with signal transducing subunits to prevent its degradation, unlike the homologous receptor FcgammaRIIIb that is expressed as a GPI-anchored molecule. Therefore, to simplify the production of cell lines as reliable assay components, we expressed FcgammaRIIIa as a GPI-anchored molecule. Separate, stable CHO cell lines that express either the 158F or the higher-affinity 158V allotype of FcgammaRIIIa were isolated using fluorescence-activated cell sorting. The identities of the expressed receptors were confirmed using a panel of monoclonal antibodies that distinguish between subclasses and allotypes of FcgammaRIII and the cell lines were shown to have slightly higher levels of receptor than FcgammaRIII-positive peripheral blood mononuclear cells. Because the affinity of FcgammaRIIIa for IgG is intermediate amongst the receptors that bind IgG, we were able to use these cell lines to develop flow cytometric assays to measure the binding of both complexed and monomeric immunoglobulin. Thus, by choosing the appropriate method, weakly- or strongly-binding IgG can be efficiently compared. We have quantified the difference in the binding of wildtype IgG1 and IgG3 molecules to the two functional allotypes of the receptor and report that the FcgammaRIIIa-158V-antibody interaction is 3

  9. Synthesis in situ of gold nanoparticles by a dialkynyl Fischer carbene complex anchored to glass surfaces

    International Nuclear Information System (INIS)

    Bertolino, María Candelaria; Granados, Alejandro Manuel

    2016-01-01

    Highlights: • Fischer carbene 1-W reacts via cycloaddition without Cu(I) with azide terminal surface. • This reaction on the surface is regioselective to internal triple bond of 1-W. • 1-W bound to glass surface produce AuNps in situ fixed to the surface. • This ability is independent of how 1-W is bonded to the surface. • This hybrid surface can be valuable as SERS substrate or in heterogeneous catalysis. - Abstract: In this work we present a detailed study of classic reactions such as “click reaction” and nucleophilic substitution reaction but on glass solid surface (slides). We used different reactive center of a dialkynylalcoxy Fischer carbene complex of tungsten(0) to be anchored to modified glass surface with amine, to obtain aminocarbene, and azide terminal groups. These cycloaddition reaction showed regioselectivity to internal triple bond of dialkynyl Fischer carbene complex without Cu(I) as catalyst. Anyway the carbene anchored was able to act as a reducing agent to produce in situ very stable gold nanoparticles fixed on surface. We showed the characterization of modified glasses by contact angle measurements and XPS. Synthesized nanoparticles were characterized by SEM, XPS, EDS and UV–vis. The modified glasses showed an important enhancement Raman-SERS. This simple, fast and robust method to create a polifunctional and hybrid surfaces can be valuable in a wide range of applications such as Raman-SERS substrates and other optical fields.

  10. Synthesis in situ of gold nanoparticles by a dialkynyl Fischer carbene complex anchored to glass surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Bertolino, María Candelaria, E-mail: cbertolino@fcq.unc.edu.ar; Granados, Alejandro Manuel, E-mail: ale@fcq.unc.edu.ar

    2016-10-15

    Highlights: • Fischer carbene 1-W reacts via cycloaddition without Cu(I) with azide terminal surface. • This reaction on the surface is regioselective to internal triple bond of 1-W. • 1-W bound to glass surface produce AuNps in situ fixed to the surface. • This ability is independent of how 1-W is bonded to the surface. • This hybrid surface can be valuable as SERS substrate or in heterogeneous catalysis. - Abstract: In this work we present a detailed study of classic reactions such as “click reaction” and nucleophilic substitution reaction but on glass solid surface (slides). We used different reactive center of a dialkynylalcoxy Fischer carbene complex of tungsten(0) to be anchored to modified glass surface with amine, to obtain aminocarbene, and azide terminal groups. These cycloaddition reaction showed regioselectivity to internal triple bond of dialkynyl Fischer carbene complex without Cu(I) as catalyst. Anyway the carbene anchored was able to act as a reducing agent to produce in situ very stable gold nanoparticles fixed on surface. We showed the characterization of modified glasses by contact angle measurements and XPS. Synthesized nanoparticles were characterized by SEM, XPS, EDS and UV–vis. The modified glasses showed an important enhancement Raman-SERS. This simple, fast and robust method to create a polifunctional and hybrid surfaces can be valuable in a wide range of applications such as Raman-SERS substrates and other optical fields.

  11. Glycoproteins and sialyl transferase of human B lymphoblastoid cell lines

    International Nuclear Information System (INIS)

    Lui, S.W.L.; Ng, M.H.

    1980-01-01

    We used two radiolabeling methods to study glycoproteins on the surface of lymphoblastoid cells. One of the methods affects tritiation of residues which are oxidized with galactose oxidase and the other causes tritiation of neuraminic acid residues. This approach was shown to allow a better resolution of cell surface glycoproteins than if either method were used alone. Glycoproteins of B 1 - 19 cells which harbor the Epstein-Barr virus genomes were compared with those of its parental cell line, BJAB, which does not harbor the viral genomes. These studies did not reveal a unique viral protein. A 28,000 mol. wt. glycoprotein was found to be the most prominent neuraminic acidlabeled product of B 1 - 19 cells and also of the two other cell lines, Raji and Ly38, which harbor the EBV genomes. A similar molecular weight species from BJAB cells identified by galactose oxidase labeling might be deficient in neuraminic acid residues as it was poorly labeled by the periodate oxidation method. The neuraminic acid content and level of sialyl transferase of BJAB cells were found to be lower than those of the other cell lines studied. (auth.)

  12. Dual modifications strategy to quantify neutral and sialylated N-glycans simultaneously by MALDI-MS.

    Science.gov (United States)

    Zhou, Hui; Warren, Peter G; Froehlich, John W; Lee, Richard S

    2014-07-01

    Differences in ionization efficiency among neutral and sialylated glycans prevent direct quantitative comparison by their respective mass spectrometric signals. To overcome this challenge, we developed an integrated chemical strategy, Dual Reactions for Analytical Glycomics (DRAG), to quantitatively compare neutral and sialylated glycans simultaneously by MALDI-MS. Initially, two glycan samples to be compared undergo reductive amination with 2-aminobenzoic acid and 2-(13)[C6]-aminobenzoic acid, respectively. The different isotope-incorporated glycans are then combined and subjected to the methylamidation of the sialic acid residues in one mixture, homogenizing the ionization responses for all neutral and sialylated glycans. By this approach, the expression change of relevant glycans between two samples is proportional to the ratios of doublet signals with a static 6 Da mass difference in MALDI-MS and the change in relative abundance of any glycan within samples can also be determined. The strategy was chemically validated using well-characterized N-glycans from bovine fetuin and IgG from human serum. By comparing the N-glycomes from a first morning (AM) versus an afternoon (PM) urine sample obtained from a single donor, we further demonstrated the ability of DRAG strategy to measure subtle quantitative differences in numerous urinary N-glycans.

  13. Novel anti-Sialyl-Tn monoclonal antibodies and antibody-drug conjugates demonstrate tumor specificity and anti-tumor activity.

    Science.gov (United States)

    Prendergast, Jillian M; Galvao da Silva, Ana Paula; Eavarone, David A; Ghaderi, Darius; Zhang, Mai; Brady, Dane; Wicks, Joan; DeSander, Julie; Behrens, Jeff; Rueda, Bo R

    Targeted therapeutics that can differentiate between normal and malignant tumor cells represent the ideal standard for the development of a successful anti-cancer strategy. The Sialyl-Thomsen-nouveau antigen (STn or Sialyl-Tn, also known as CD175s) is rarely seen in normal adult tissues, but it is abundantly expressed in many types of human epithelial cancers. We have identified novel antibodies that specifically target with high affinity the STn glycan independent of its carrier protein, affording the potential to recognize a wider array of cancer-specific sialylated proteins. A panel of murine monoclonal anti-STn therapeutic antibodies were generated and their binding specificity and efficacy were characterized in vitro and in in vivo murine cancer models. A subset of these antibodies were conjugated to monomethyl auristatin E (MMAE) to generate antibody-drug conjugates (ADCs). These ADCs demonstrated in vitro efficacy in STn-expressing cell lines and significant tumor growth inhibition in STn-expressing tumor xenograft cancer models with no evidence of overt toxicity.

  14. A novel biosurfactant produced by Aureobasidium pullulans L3-GPY from a tiger lily wild flower, Lilium lancifolium Thunb.

    Science.gov (United States)

    Kim, Jong Shik; Lee, In Kyoung; Yun, Bong Sik

    2015-01-01

    Yeast biosurfactants are important biotechnological products in the food industry, and they have medical and cosmeceutical applications owing to their specific modes of action, low toxicity, and applicability. Thus, we have isolated and examined biosurfactant-producing yeast for various industrial and medical applications. A rapid and simple method was developed to screen biosurfactant-producing yeasts for high production of eco-friendly biosurfactants. Using this method, several potential niches of biosurfactant-producing yeasts, such as wild flowers, were investigated. We successfully selected a yeast strain, L3-GPY, with potent surfactant activity from a tiger lily, Lilium lancifolium Thunb. Here, we report the first identification of strain L3-GPY as the black yeast Aureobasidium pullulans. In addition, we isolated a new low-surface-tension chemical, designated glycerol-liamocin, from the culture supernatant of strain L3-GPY through consecutive chromatography steps, involving an ODS column, solvent partition, silica gel, Sephadex LH-20, and an ODS Sep-Pak cartridge column. The chemical structure of glycerol-liamocin, determined by mass spectrometry and nuclear magnetic resonance spectroscopy, indicates that it is a novel compound with the molecular formula C33H62O12. Furthermore, glycerol-liamocin exhibited potent biosurfactant activity (31 mN/m). These results suggest that glycerol-liamocin is a potential novel biosurfactantfor use in various industrial applications.

  15. Surface analysis of PEGylated nano-shields on nanoparticles installed by hydrophobic anchors

    DEFF Research Database (Denmark)

    Ebbesen, M F; Whitehead, Bradley Joseph; Gonzalez, Borja Ballarin

    2013-01-01

    and cellular interactions. Methods: Poly(lactic-co-glycolic acid) (PLGA) nanoparticles were prepared with a hydrophilic PEGylated "nano-shield" inserted at different levels by hydrophobic anchoring using either a phospholipid-PEG conjugate or the copolymer PLGA-block-PEG by an emulsification/diffusion method....... Surface and bulk analysis was performed including X-ray photoelectron spectroscopy (XPS), nuclear magnetic resonance spectroscopy (NMR) and zeta potential. Cellular uptake was investigated in RAW 264.7 macrophages by flow cytometry. Results: Sub-micron nanoparticles were formed and the combination of (NMR...

  16. Robotic Ankle for Omnidirectional Rock Anchors

    Science.gov (United States)

    Parness, Aaron; Frost, Matthew; Thatte, Nitish

    2013-01-01

    Future robotic exploration of near-Earth asteroids and the vertical and inverted rock walls of lava caves and cliff faces on Mars and other planetary bodies would require a method of gripping their rocky surfaces to allow mobility without gravitational assistance. In order to successfully navigate this terrain and drill for samples, the grippers must be able to produce anchoring forces in excess of 100 N. Additionally, the grippers must be able to support the inertial forces of a moving robot, as well gravitational forces for demonstrations on Earth. One possible solution would be to use microspine arrays to anchor to rock surfaces and provide the necessary load-bearing abilities for robotic exploration of asteroids. Microspine arrays comprise dozens of small steel hooks supported on individual suspensions. When these arrays are dragged along a rock surface, the steel hooks engage with asperities and holes on the surface. The suspensions allow for individual hooks to engage with asperities while the remaining hooks continue to drag along the surface. This ensures that the maximum possible number of hooks engage with the surface, thereby increasing the load-bearing abilities of the gripper. Using the microspine array grippers described above as the end-effectors of a robot would allow it to traverse terrain previously unreachable by traditional wheeled robots. Furthermore, microspine-gripping robots that can perch on cliffs or rocky walls could enable a new class of persistent surveillance devices for military applications. In order to interface these microspine grippers with a legged robot, an ankle is needed that can robotically actuate the gripper, as well as allow it to conform to the large-scale irregularities in the rock. The anchor serves three main purposes: deploy and release the anchor, conform to roughness or misalignment with the surface, and cancel out any moments about the anchor that could cause unintentional detachment. The ankle design contains a

  17. Epididymosomes: transfer of fertility-modulating proteins to the sperm surface.

    Science.gov (United States)

    Martin-DeLeon, Patricia A

    2015-01-01

    A variety of glycosylphosphatidylinositol (GPI)-linked proteins are acquired on spermatozoa from epididymal luminal fluids (ELF) during sperm maturation. These proteins serve roles in immunoprotection and in key steps of fertilization such as capacitation, acrosomal exocytosis and sperm-egg interactions. Their acquisition on sperm cells is mediated both by membrane vesicles (epididymosomes, EP) which were first reported to dock on the sperm surface, and by lipid carriers which facilitate the transfer of proteins associated with the membrane-free fraction of ELF. While the nonvesicular fraction is more efficient, both pathways are dependent on hydrophobic interactions between the GPI-anchor and the external lipid layer of the sperm surface. More recently proteomic and hypothesis-driven studies have shown that EP from several mammals carry transmembrane (TM) proteins, including plasma membrane Ca 2 + -ATPase 4 (PMCA4). Synthesized in the testis, PMCA4 is an essential protein and the major Ca 2 + efflux pump in murine spermatozoa. Delivery of PMCA4 to spermatozoa from bovine and mouse EP during epididymal maturation and in vitro suggests that the docking of EP on the sperm surface precedes fusion, and experimental evidence supports a fusogenic mechanism for TM proteins. Fusion is facilitated by CD9, which generates fusion-competent sites on membranes. On the basis of knowledge of PMCA4's interacting partners a number of TM and membrane-associated proteins have been identified or are predicted to be present, in the epididymosomal cargo deliverable to spermatozoa. These Ca 2 + -dependent proteins, undetected in proteomic studies, play essential roles in sperm motility and fertility, and their detection highlights the usefulness of the hypothesis-driven approach.

  18. Epididymosomes: transfer of fertility-modulating proteins to the sperm surface

    Directory of Open Access Journals (Sweden)

    Patricia A Martin-DeLeon

    2015-01-01

    Full Text Available A variety of glycosylphosphatidylinositol (GPI-linked proteins are acquired on spermatozoa from epididymal luminal fluids (ELF during sperm maturation. These proteins serve roles in immunoprotection and in key steps of fertilization such as capacitation, acrosomal exocytosis and sperm-egg interactions. Their acquisition on sperm cells is mediated both by membrane vesicles (epididymosomes, EP which were first reported to dock on the sperm surface, and by lipid carriers which facilitate the transfer of proteins associated with the membrane-free fraction of ELF. While the nonvesicular fraction is more efficient, both pathways are dependent on hydrophobic interactions between the GPI-anchor and the external lipid layer of the sperm surface. More recently proteomic and hypothesis-driven studies have shown that EP from several mammals carry transmembrane (TM proteins, including plasma membrane Ca 2 + -ATPase 4 (PMCA4. Synthesized in the testis, PMCA4 is an essential protein and the major Ca 2 + efflux pump in murine spermatozoa. Delivery of PMCA4 to spermatozoa from bovine and mouse EP during epididymal maturation and in vitro suggests that the docking of EP on the sperm surface precedes fusion, and experimental evidence supports a fusogenic mechanism for TM proteins. Fusion is facilitated by CD9, which generates fusion-competent sites on membranes. On the basis of knowledge of PMCA4′s interacting partners a number of TM and membrane-associated proteins have been identified or are predicted to be present, in the epididymosomal cargo deliverable to spermatozoa. These Ca 2 + -dependent proteins, undetected in proteomic studies, play essential roles in sperm motility and fertility, and their detection highlights the usefulness of the hypothesis-driven approach.

  19. Distinguishing two types of gray mullet, Mugil cephalus L. (Mugiliformes: Mugilidae), by using glucose-6-phosphate isomerase (GPI) allozymes with special reference to enzyme activities.

    Science.gov (United States)

    Huang, C S; Weng, C F; Lee, S C

    2001-06-01

    The resident and migratory types of gray mullet, Mugil cephalus, on the coast of Taiwan can not be separated morphologically. Allozyme analysis was applied to estimate genetic variation between the two types of gray mullet and to test whether they belong to different populations. After starch gel electrophoresis, different allelic frequency spectra of glucose-6-phosphate isomerase-A (GPI-A) between stocks was observed. The resident stock contained Gpi-A(135) and Gpi-A(100), whereas the migratory type contained Gpi-A(100) only. In addition, GPI activities of locus A showed two distinct profiles between the two alleles. The results broadly revealed that Gpi-A allelic frequency was not regulated by temperature changes even after 6 months of thermal acclimation. This suggests that natural selection may play a role in shaping the allelic frequency change during the migratory journey. These findings suggest that the Gpi-A allelic difference can be used for population discrimination.

  20. Stress analysis of liners for prestressed concrete reactor pressure vessels with regard to non-linear behaviour of liner material and of anchor-characteristics

    International Nuclear Information System (INIS)

    Oberpichler, R.; Schnellenbach, G.

    1975-01-01

    The thin liner attached by anchors like a membrane to the interior wall of a prestressed concrete reactor pressure vessel (PCRV) has to provide the leak-tightness of the vessel. Furthermore the liner may serve as internal shuttering for placing of concrete as well as a support for the cooling system. The two-dimensional behaviour of the liner is investigated with regard to non-linear anchor-characteristics and non-linear material behaviour of the liner. The analysis is based on a plane stress model under the assumption of a membrane state of the liner. Calculations are performed by the dynamic relaxation method. With the aid of available non-linear stress-strain diagrams, describing the post-buckling behaviour, individual panels are considered as buckled ones. The adjacent unbuckled panels are calculated on other non-linear diagrams. Strains and stresses in the liner and additional shear loads in the anchors can be calculated with arbitrary sizing and spacing of the anchors. With respect to the parameters they are easily controlled. Since actual loads on the liner are defined by the PCRV-behaviour, an economical and safe design is possible. Finally an extreme case is calculated to assess the maximum value of the shear-forces assuming zero post-buckling capacity for the buckled panel. (Auth.)

  1. Stretching of a polymer chain anchored to a surface: the massive field theory approach

    International Nuclear Information System (INIS)

    Usatenko, Zoryana

    2014-01-01

    Taking into account the well-known correspondence between the field theoretical φ 4 O(n)-vector model in the limit n → 0 and the behaviour of long-flexible polymer chains, the investigation of stretching of an ideal and a real polymer chain with excluded volume interactions in a good solvent anchored to repulsive and inert surfaces is performed. The calculations of the average stretching force which arises when the free end of a polymer chain moves away from a repulsive or inert surface are performed up to one-loop order of the massive field theory approach in fixed space dimensions d = 3. The analysis of the obtained results indicates that the average stretching force for a real polymer chain anchored to a repulsive surface demonstrates different behaviour for the cases z-tilde ≪1 and z-tilde ≫1, where z-tilde =z ′ /R z . Besides, the results obtained in the framework of the massive field theory approach are in good agreement with previous theoretical results for an ideal polymer chain and results of a density functional theory approach for the region of small applied forces when deformation of a polymer chain in the direction of the applied force is not bigger than the linear extension of a polymer chain in this direction. The better agreement between these two methods is observed in the case where the number of monomers increases and the polymer chain becomes longer. (paper)

  2. Glycopeptide profiling of beta-2-glycoprotein I by mass spectrometry reveals attenuated sialylation in patients with antiphospholipid syndrome

    DEFF Research Database (Denmark)

    Kondo, Akira; Miyamoto, Toshiaki; Yonekawa, Osamu

    2009-01-01

    beta2-glycoprotein I (beta2GPI) is a five-domain protein associated with the antiphospholipid syndrome (APS), however, its normal biological function is yet to be defined. beta2GPI is N-glycosylated at several asparagine residues and the glycan moiety conjugated to residue 143 has been proposed t...

  3. Expression and immunological characterisation of Eimeria tenella glycosylphosphatidylinositol-anchored surface antigen-5

    Science.gov (United States)

    Ho, Sue-Kim; Nathan, Sheila; Wan, Kiew-Lian

    2016-11-01

    Eimeria tenella is the most pathogenic of the Eimeria species that infect chickens and causes huge economic losses to the poultry industry. The glycosylphosphatidylinositol-anchored surface antigen-5 (SAG5) found on the surface of the parasite has been shown to activate the chicken's immune system. In this study, recombinant SAG5 was expressed, purified and used to investigate the immune-inducing characteristics of the molecule. Chickens were immunized with purified recombinant SAG5 and sera were subjected to Enzyme-linked Immunosorbant Assay (ELISA). Results indicated that specific antibodies against rSAG5 were produced, with IgG detected at a higher level compared to IgA and IgM. Information on the immunological responses elicited by SAG5 provides essential knowledge that will contribute towards the effort to develop more effective strategies against coccidiosis.

  4. Long-Term Effect of GPi-DBS in a Patient With Generalized Dystonia Due to GLUT1 Deficiency Syndrome

    Directory of Open Access Journals (Sweden)

    Idil Hanci

    2018-05-01

    Full Text Available Treatment outcomes from pallidal deep brain stimulation are highly heterogeneous reflecting the phenotypic and etiologic spectrum of dystonia. Treatment stratification to neurostimulation therapy primarily relies on the phenotypic motor presentation; however, etiology including genetic factors are increasingly recognized as modifiers of treatment outcomes. Here, we describe a 53 year-old female patient with a progressive generalized dystonia since age 25. The patient underwent deep brain stimulation of the globus pallidus internus (GPi-DBS at age 44. Since the clinical phenotype included mobile choreo-dystonic features, we expected favorable therapeutic outcome from GPi-DBS. Although mobile dystonia components were slightly improved in the long-term outcome from GPi-DBS the overall therapeutic response 9 years from implantation was limited when comparing “stimulation off” and “stimulation on” despite of proper electrode localization and sufficient stimulation programming. In order to further understand the reason for this limited motor symptom response, we aimed to clarify the etiology of generalized dystonia in this patient. Genetic testing identified a novel heterozygous pathogenic SLC2A1 mutation as cause of glucose transporter type 1 deficiency syndrome (GLUT1-DS. This case report presents the first outcome of GPi-DBS in a patient with GLUT1-DS, and suggests that genotype relations may increasingly complement phenotype-based therapy stratification of GPi-DBS in dystonia.

  5. Comparative Study on Different Slot Forms of Prestressed Anchor Blocks

    Science.gov (United States)

    Fan, Rong; Si, Jianhui; Jian, Zheng

    2018-03-01

    In this paper, two models of prestressed pier, rectangular cavity anchor block and arch hollow anchor block are established. The ABAQUS software was used to calculate the stress of the surface of the neck of the pier and the cavity of the anchor block, through comparative analysis. The results show that compared with the rectangular cavity anchor block, the stress of the pier and the cavity can be effectively reduced when the arch hole is used, and the amount of prestressed anchor can be reduced, so as to obtain obvious economic benefits.

  6. Yeast cell surface display: An efficient strategy for improvement of bioethanol fermentation performance.

    Science.gov (United States)

    Chen, Xianzhong

    2017-03-04

    The cell surface serves as a functional interface between the inside and the outside of the cell. Within the past 20 y the ability of yeast (Saccharomyces cerevisiae) to display heterologous proteins on the cell surface has been demonstrated. Furthermore, S. cerevisiae has been both developed and applied in expression of various proteins on the cell surface. Using this novel and useful strategy, proteins and peptides of various kinds can be displayed on the yeast cell surface by fusing the protein of interest with the glycosylphosphatidylinositol (GPI)-anchoring system. Consolidated bioprocessing (CBP) using S. cerevisiae represents a promising technology for bioethanol production. However, further work is needed to improve the fermentation performance. There is some excellent previous research regarding construction of yeast biocatalyst using the surface display system to decrease cost, increase efficiency of ethanol production and directly utilize starch or biomass for fuel production. In this commentary, we reviewed the yeast surface display system and highlighted recent work. Additionally, the strategy for decrease of phytate phosphate content in dried distillers grains with solubles (DDGS) by display of phytase on the yeast cell surface is discussed.

  7. Anchorage Behaviors of Frictional Tieback Anchors in Silty Sand

    Science.gov (United States)

    Hsu, Shih-Tsung; Hsiao, Wen-Ta; Chen, Ke-Ting; Hu, Wen-Chi; Wu, Ssu-Yi

    2017-06-01

    Soil anchors are extensively used in geotechnical applications, most commonly serve as tieback walls in deep excavations. To investigate the anchorage mechanisms of this tieback anchor, a constitutive model that considers both strain hardening and softening and volume dilatancy entitled SHASOVOD model, and FLAC3D software are used to perform 3-D numerical analyses. The results from field anchor tests are compared with those calculated by numerical analyses to enhance the applicability of the numerical method. After the calibration, this research carried out the parameter studies by numerical analyses. The numerical results reveal that whether the yield of soil around an anchor develops to ground surface and/or touches the diaphragm wall depending on the overburden depth H and the embedded depth Z of an anchor, this study suggests the minimum overburden and embedded depths to avoid the yield of soils develop to ground surface and/or touch the diaphragm wall. When the embedded depth, overburden depth or fixed length of an anchor increases, the anchorage capacity also increases. Increasing fixed length should be the optimum method to increase the anchorage capacity for fixed length less than 20m. However, when the fixed length of an anchor exceeds 30 m, the increasing rate of anchorage capacity per fixed length decreases, and progressive yield occurs obviously between the fixed length and surrounding soil.

  8. Rational Design of a New Trypanosoma rangeli Trans-Sialidase for Efficient Sialylation of Glycans

    DEFF Research Database (Denmark)

    Jers, Carsten; Michalak, Malwina; Larsen, Dorte Møller

    2014-01-01

    This paper reports rational engineering of Trypanosoma rangeli sialidase to develop an effective enzyme for a potentially important type of reactivity: production of sialylated prebiotic glycans. The Trypanosoma cruzi trans-sialidase and the homologous T. rangeli sialidase has previously been use...

  9. Modified Kidner procedure utilizing a Mitek bone anchor.

    Science.gov (United States)

    Dawson, D M; Julsrud, M E; Erdmann, B B; Jacobs, P M; Ringstrom, J B

    1998-01-01

    The recent development of small bone suture anchors has created several potential applications in reconstructive surgery of the foot. Mitek bone anchors are simple to insert, require less aggressive dissection and surgical time than reefing of the redundant posterior tibial tendon, and are a reliable method of tendon-to-bone fixation. Mitek bone anchors are an excellent technique for the treatment of redundant tibialis posterior tendon following a modified Kidner procedure. In modified Kidner procedures involving an excessively large os tibiale externum, Mitek anchoring of the redundant tibialis posterior tendon to the navicular bone is an excellent means for secure plication of the posterior tibial tendon in cases involving intraoperative tendon laxity. A description of the Mitek Anchor System and technique of application in a modified Kinder procedure is presented. The purpose of this study was to describe patient satisfaction and long-term clinical outcomes of the modified Kinder procedure with and without the Mitek bone anchoring system. A retrospective study of the modified Kinder procedure was performed with 13 patients being evaluated, seven with Mitek anchoring and six without. The University of Maryland 100-point Painful Foot Center Scoring System was modified to be more specific to the modified Kinder procedure for assessment of subjective long-term results. Patient overall satisfaction was rated good to excellent by 85.6% of patients in the Mitek group and by 100% of patients in the non-Mitek group. Use of the Mitek anchor allowed for quicker postoperative recovery to resumption of ambulation without assistive devices (average of 3 weeks vs. 4.42 weeks) and a quicker return to pain-free ambulation in normal shoegear (average of 4 weeks vs. 6 weeks). Mitek anchoring of the tibialis posterior tendon, theoretically, increases medial arch support as evidenced by 14% of the Mitek group and 67% of the non-Mitek group requiring postoperative orthotics.

  10. Spin selection at organic spinterface by anchoring group

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Zhao; Qiu, Shuai; Miao, Yuan-yuan; Ren, Jun-feng; Wang, Chuan-kui [School of Physics and Electronics, Shandong Normal University, Jinan 250014 (China); Hu, Gui-chao, E-mail: hgc@sdnu.edu.cn [School of Physics and Electronics, Shandong Normal University, Jinan 250014 (China); Institute of Theoretical Physics, Technische Universität Dresden, 01062 Dresden (Germany)

    2017-07-01

    Highlights: • The sign of interfacial spin polarization can be selected by using different anchoring groups. • A sp{sup 3}-d or sp-d hybridization may occur and induce spin polarization when the anchoring group changes. • Interfacial spin polarization depends on both the type of the outer orbital of the anchoring atom as well as its energy. - Abstract: Control of organic interfacial spin polarization is crucial in organic spintronics. Based on ab initio theory, here we proposed a spin selection at organic interface via anchoring group by adsorbing an organic molecule onto Ni(111) surface. The results demonstrate that either a positive or negative interfacial spin polarization may be obtained by choosing different anchoring groups. The orbital analysis via the projected density of states shows that the interfacial spin polarization is sensitive to the hybridization of the outer orbital of the anchoring atom as well as its energy relative to the d orbital of the ferromagnetic atom. The work indicates a feasible way to realize spin selection at the organic spinterface by anchoring group.

  11. Glypican-1 mediates both prion protein lipid raft association and disease isoform formation.

    Directory of Open Access Journals (Sweden)

    David R Taylor

    2009-11-01

    Full Text Available In prion diseases, the cellular form of the prion protein, PrP(C, undergoes a conformational conversion to the infectious isoform, PrP(Sc. PrP(C associates with lipid rafts through its glycosyl-phosphatidylinositol (GPI anchor and a region in its N-terminal domain which also binds to heparan sulfate proteoglycans (HSPGs. We show that heparin displaces PrP(C from rafts and promotes its endocytosis, suggesting that heparin competes with an endogenous raft-resident HSPG for binding to PrP(C. We then utilised a transmembrane-anchored form of PrP (PrP-TM, which is targeted to rafts solely by its N-terminal domain, to show that both heparin and phosphatidylinositol-specific phospholipase C can inhibit its association with detergent-resistant rafts, implying that a GPI-anchored HSPG targets PrP(C to rafts. Depletion of the major neuronal GPI-anchored HSPG, glypican-1, significantly reduced the raft association of PrP-TM and displaced PrP(C from rafts, promoting its endocytosis. Glypican-1 and PrP(C colocalised on the cell surface and both PrP(C and PrP(Sc co-immunoprecipitated with glypican-1. Critically, treatment of scrapie-infected N2a cells with glypican-1 siRNA significantly reduced PrP(Sc formation. In contrast, depletion of glypican-1 did not alter the inhibitory effect of PrP(C on the beta-secretase cleavage of the Alzheimer's amyloid precursor protein. These data indicate that glypican-1 is a novel cellular cofactor for prion conversion and we propose that it acts as a scaffold facilitating the interaction of PrP(C and PrP(Sc in lipid rafts.

  12. Numerical investigation to the dual-fuel spray combustion process in an ethanol direct injection plus gasoline port injection (EDI + GPI) engine

    International Nuclear Information System (INIS)

    Huang, Yuhan; Hong, Guang; Huang, Ronghua

    2015-01-01

    Highlights: • A 5D PDF table was used to model the dual-fuel turbulence–chemistry interactions. • The cooling effect of ethanol direct injection (EDI) was examined. • The higher flame speed of ethanol in EDI + GPI increased the thermal efficiency. • The partially premixed combustion in EDI + GPI reduced the combustion temperature. • Ethanol’s low evaporation rate in low temperature led to incomplete combustion. - Abstract: Ethanol direct injection plus gasoline port injection (EDI + GPI) is a new technology to make the use of ethanol fuel more effective and efficient in spark ignition engines. Multi-dimensional computational fluid dynamics modelling was conducted on an EDI + GPI engine in both single and dual fuelled conditions. The in-cylinder flow field was solved in the realizable k−ε turbulence model with detailed engine geometry. The temporal and spatial distributions of the liquid and vapour fuels were simulated with the spray breakup and evaporation models. The combustion process was modelled with the partially premixed combustion concept in which both mixture fraction and progress variable were solved. The three-dimensional and five-dimensional presumed Probability Density Function (PDF) look-up tables were used to model the single-fraction-mixture and two-fraction-mixture turbulence–chemistry interactions respectively. The model was verified by comparing the numerical and experimental results of spray pattern and cylinder pressure. The simulation results showed that the combustion process of EDI + GPI dual-fuelled condition was partially premixed combustion because of the low evaporation rate of ethanol spray in low temperature environment before combustion. Compared with GPI only, the higher flame speed of ethanol fuel contributed to the greater pressure rise rate and maximum cylinder pressure in EDI + GPI condition, which consequently resulted in higher power output and thermal efficiency. The lower adiabatic flame temperature of

  13. Clathrin-independent pathways do not contribute significantly to endocytic flux.

    Science.gov (United States)

    Bitsikas, Vassilis; Corrêa, Ivan R; Nichols, Benjamin J

    2014-09-17

    Several different endocytic pathways have been proposed to function in mammalian cells. Clathrin-coated pits are well defined, but the identity, mechanism and function of alternative pathways have been controversial. Here we apply universal chemical labelling of plasma membrane proteins to define all primary endocytic vesicles, and labelling of specific proteins with a reducible SNAP-tag substrate. These approaches provide high temporal resolution and stringent discrimination between surface-connected and intracellular membranes. We find that at least 95% of the earliest detectable endocytic vesicles arise from clathrin-coated pits. GPI-anchored proteins, candidate cargoes for alternate pathways, are also found to enter the cell predominantly via coated pits. Experiments employing a mutated clathrin adaptor reveal distinct mechanisms for sorting into coated pits, and thereby explain differential effects on the uptake of transferrin and GPI-anchored proteins. These data call for a revision of models for the activity and diversity of endocytic pathways in mammalian cells.

  14. Defining the Conformational Features of Anchorless, Poorly Neuroinvasive Prions

    NARCIS (Netherlands)

    Bett, C.; Kurt, T.D.; Lucero, M.; Trejo, M.; Rozemuller, A.J.M.; Kong, Q.Z.; Nilsson, K.P.R.; Masliah, E.; Oldstone, M.B.; Sigurdson, C.J.

    2013-01-01

    Infectious prions cause diverse clinical signs and form an extraordinary range of structures, from amorphous aggregates to fibrils. How the conformation of a prion dictates the disease phenotype remains unclear. Mice expressing GPI-anchorless or GPI-anchored prion protein exposed to the same

  15. Asparagine-linked oligosaccharides on lutropin, follitropin, and thyrotropin: structural elucidation of the sulfated and sialylated oligosaccharides on bovine, ovine, and human pituitary glycoprotein hormones

    International Nuclear Information System (INIS)

    Green, E.D.; Baenziger, J.U.

    1988-01-01

    The authors have elucidated the structures of the anionic asparagine-linked oligosaccharides present on the glycoprotein hormones lutropin (luteinizing hormone), follitropin (follicle-stimulating hormone), and thyrotropin (thyroid-stimulating hormone). Purified hormones, isolated from bovine, ovine, and human pituitaries, were digested with N-glycanase, and the released oligosaccharides were reduced with NaB[ 3 H] 4 . The 3 H-labeled oligosaccharides from each hormone were then fractionated by anion-exchange high performance liquid chromatography (HPLC) into populations differing in the number of sulfate and/or sialic acid moieties. The sulfated, sialylated, and sulfated/sialylated structures, which together comprised 67-90% of the asparagine-linked oligosaccharides on the pituitary glycoprotein hormones, were highly heterogeneous and displayed hormone- as well as animal species-specific features. A previously uncharacterized dibranched oligosaccharide, bearing one residue each of sulfate and sialic acid, was found on all of the hormones except bovine lutropin. In this study, they describe the purification and detailed structural characterizations of the sulfated, sialylated, and sulfated/sialylated oligosaccharides found on lutropin, follitropin, and thyrotropin from several animal species

  16. Discovery of ebselen as an inhibitor of Cryptosporidium parvum glucose-6-phosphate isomerase (CpGPI by high-throughput screening of existing drugs

    Directory of Open Access Journals (Sweden)

    Rana Eltahan

    2018-04-01

    Full Text Available Cryptosporidium parvum is a water-borne and food-borne apicomplexan pathogen. It is one of the top four diarrheal-causing pathogens in children under the age of five in developing countries, and an opportunistic pathogen in immunocompromised individuals. Unlike other apicomplexans, C. parvum lacks Kreb's cycle and cytochrome-based respiration, thus relying mainly on glycolysis to produce ATP. In this study, we characterized the primary biochemical features of the C. parvum glucose-6-phosphate isomerase (CpGPI and determined its Michaelis constant towards fructose-6-phosphate (Km = 0.309 mM, Vmax = 31.72 nmol/μg/min. We also discovered that ebselen, an organoselenium drug, was a selective inhibitor of CpGPI by high-throughput screening of 1200 known drugs. Ebselen acted on CpGPI as an allosteric noncompetitive inhibitor (IC50 = 8.33 μM; Ki = 36.33 μM, while complete inhibition of CpGPI activity was not achieved. Ebselen could also inhibit the growth of C. parvum in vitro (EC50 = 165 μM at concentrations nontoxic to host cells, albeit with a relatively small in vitro safety window of 4.2 (cytotoxicity TC50 on HCT-8 cells = 700 μM. Additionally, ebselen might also target other enzymes in the parasite, leading to the parasite growth reduction. Therefore, although ebselen is useful in studying the inhibition of CpGPI enzyme activity, further proof is needed to chemically and/or genetically validate CpGPI as a drug target. Keywords: Apicomplexan, Cryptosporidium parvum, Glucose-6-phosphate isomerase (GPI, Ebselen

  17. Pro-inflammatory State in Monoclonal Gammopathy of Undetermined Significance and in Multiple Myeloma Is Characterized by Low Sialylation of Pathogen-Specific and Other Monoclonal Immunoglobulins

    Directory of Open Access Journals (Sweden)

    Adrien Bosseboeuf

    2017-10-01

    Full Text Available Multiple myeloma (MM and its pre-cancerous stage monoclonal gammopathy of undetermined significance (MGUS allow to study immune responses and the chronology of inflammation in the context of blood malignancies. Both diseases are characterized by the production of a monoclonal immunoglobulin (mc Ig which for subsets of MGUS and MM patients targets pathogens known to cause latent infection, a major cause of inflammation. Inflammation may influence the structure of both polyclonal (pc Ig and mc Ig produced by malignant plasma cells via the sialylation of Ig Fc fragment. Here, we characterized the sialylation of purified mc and pc IgGs from 148 MGUS and MM patients, in comparison to pc IgGs from 46 healthy volunteers. The inflammatory state of patients was assessed by the quantification in serum of 40 inflammation-linked cytokines, using Luminex technology. While pc IgGs from MGUS and MM patients showed heterogeneity in sialylation level, mc IgGs from both MGUS and MM patients exhibited a very low level of sialylation. Furthermore, mc IgGs from MM patients were less sialylated than mc IgGs from MGUS patients (p < 0.01, and mc IgGs found to target an infectious pathogen showed a lower level of sialylation than mc IgGs of undetermined specificity (p = 0.048. Regarding inflammation, 14 cytokines were similarly elevated with a p value < 0.0001 in MGUS and in MM compared to healthy controls. MM differed from MGUS by higher levels of HGF, IL-11, RANTES and SDF-1-α (p < 0.05. MGUS and MM patients presenting with hyposialylated pc IgGs had significantly higher levels of HGF, IL-6, tumor necrosis factor-α, TGF-β1, IL-17, and IL-33 compared to patients with hyper-sialylated pc IgGs (p < 0.05. In MGUS and in MM, the degree of sialylation of mc and pc IgGs and the levels of four cytokines important for the anti-microbial response were correlated, either positively (IFN-α2, IL-13 or negatively (IL-17, IL-33. Thus in MGUS as in MM

  18. The Analysis Stability of Anchor Retaining Wall

    International Nuclear Information System (INIS)

    Benamara, F. Z.; Belabed, L

    2011-01-01

    The construction of anchored retaining walls reach every day in the field of Civil Engineering especially in public works. Their dimensioning and stability are the axes of research for geotechnical. The rule is to reduce the active forces of the slide and increase the effective normal stress on the rupture surface. So that, we anchored tied-back (constituted by steel cables) in the stable ground located under the failure surface and we apply at the top a traction force. This effort can be distributed over the ground surface by means of small plates or massive reinforced concrete. The study of the stability of anchored retaining wall was also performed by using software GEO4. Many cases can be solved using analytical solutions available in the group GEO4 program, but for our standard model solution studied analytically proved unsatisfactory so we used a numerical analysis based on the method of finite element in this program. The results obtained by numerical study were interpreted to identify the precision numerical predictions. Moreover these methods were useful and economics in the realization of reinforced slopes by tied-buck. (author)

  19. Cognitive and Psychiatric Effects of STN versus GPi Deep Brain Stimulation in Parkinson's Disease: A Meta-Analysis of Randomized Controlled Trials.

    Directory of Open Access Journals (Sweden)

    Jia-Wei Wang

    Full Text Available Deep brain stimulation (DBS of either the subthalamic nucleus (STN or the globus pallidus interna (GPi can reduce motor symptoms in patients with Parkinson's disease (PD and improve their quality of life. However, the effects of STN DBS and GPi DBS on cognitive functions and their psychiatric effects remain controversial. The present meta-analysis was therefore performed to clarify these issues.We searched the PUBMED, EMBASE, and the Cochrane Central Register of Controlled Trials databases. Other sources, including internet-based clinical trial registries and grey literature sources, were also searched. After searching the literature, two investigators independently performed literature screens to assess the quality of the included trials and to extract the data. The outcomes included the effects of STN DBS and GPi DBS on multiple cognitive domains, depression, anxiety, and quality of life.Seven articles related to four randomized controlled trials that included 521 participants were incorporated into the present meta-analysis. Compared with GPi DBS, STN DBS was associated with declines in selected cognitive domains after surgery, including attention, working memory and processing speed, phonemic fluency, learning and memory, and global cognition. However, there were no significant differences in terms of quality of life or psychiatric effects, such as depression and anxiety, between the two groups.A selective decline in frontal-subcortical cognitive functions is observed after STN DBS in comparison with GPi DBS, which should not be ignored in the target selection for DBS treatment in PD patients. In addition, compared to GPi DBS, STN DBS does not affect depression, anxiety, and quality of life.

  20. Cognitive and Psychiatric Effects of STN versus GPi Deep Brain Stimulation in Parkinson's Disease: A Meta-Analysis of Randomized Controlled Trials.

    Science.gov (United States)

    Wang, Jia-Wei; Zhang, Yu-Qing; Zhang, Xiao-Hua; Wang, Yun-Peng; Li, Ji-Ping; Li, Yong-Jie

    2016-01-01

    Deep brain stimulation (DBS) of either the subthalamic nucleus (STN) or the globus pallidus interna (GPi) can reduce motor symptoms in patients with Parkinson's disease (PD) and improve their quality of life. However, the effects of STN DBS and GPi DBS on cognitive functions and their psychiatric effects remain controversial. The present meta-analysis was therefore performed to clarify these issues. We searched the PUBMED, EMBASE, and the Cochrane Central Register of Controlled Trials databases. Other sources, including internet-based clinical trial registries and grey literature sources, were also searched. After searching the literature, two investigators independently performed literature screens to assess the quality of the included trials and to extract the data. The outcomes included the effects of STN DBS and GPi DBS on multiple cognitive domains, depression, anxiety, and quality of life. Seven articles related to four randomized controlled trials that included 521 participants were incorporated into the present meta-analysis. Compared with GPi DBS, STN DBS was associated with declines in selected cognitive domains after surgery, including attention, working memory and processing speed, phonemic fluency, learning and memory, and global cognition. However, there were no significant differences in terms of quality of life or psychiatric effects, such as depression and anxiety, between the two groups. A selective decline in frontal-subcortical cognitive functions is observed after STN DBS in comparison with GPi DBS, which should not be ignored in the target selection for DBS treatment in PD patients. In addition, compared to GPi DBS, STN DBS does not affect depression, anxiety, and quality of life.

  1. A non-freaked out guide to teaching the common core using the 32 literacy anchor standards to develop college- and career-ready students

    CERN Document Server

    Stuart, Dave

    2014-01-01

    Implement the Common Core for ELA without all the stress A Non-Freaked Out Guide to Teaching the Common Core uses the often-neglected anchor standards to get to the heart of the Common Core State Standards (CCSS)-teaching students the skills they need to be college and career ready. Each anchor standard is broken down into its key points, and a discussion of each anchor standard''s central purpose helps outline the context for each required skill. This easy-to-read guide gives educators the kind of clear explanations, examples, and strategies they need to feel comfortable teaching the CCSS, an

  2. The role of Listeria monocytogenes cell wall surface anchor protein LapB in virulence, adherence, and intracellular replication

    Science.gov (United States)

    Lmof2365_2117 is a Listeria monocytogenes putative cell wall surface anchor protein with a conserved domain found in collagen binding proteins. We constructed a deletion mutation in lmof2365_2117 in serotype 4b strain F2365, evaluated its virulence, and determined its ability to adhere and invade co...

  3. First principles investigations on the electronic structure of anchor groups on ZnO nanowires and surfaces

    International Nuclear Information System (INIS)

    Dominguez, A.; Lorke, M.; Rosa, A. L.; Frauenheim, Th.; Schoenhalz, A. L.; Dalpian, G. M.; Rocha, A. R.

    2014-01-01

    We report on density functional theory investigations of the electronic properties of monofunctional ligands adsorbed on ZnO-(1010) surfaces and ZnO nanowires using semi-local and hybrid exchange-correlation functionals. We consider three anchor groups, namely thiol, amino, and carboxyl groups. Our results indicate that neither the carboxyl nor the amino group modify the transport and conductivity properties of ZnO. In contrast, the modification of the ZnO surface and nanostructure with thiol leads to insertion of molecular states in the band gap, thus suggesting that functionalization with this moiety may customize the optical properties of ZnO nanomaterials.

  4. Stability Analysis of Anchored Soil Slope Based on Finite Element Limit Equilibrium Method

    Directory of Open Access Journals (Sweden)

    Rui Zhang

    2016-01-01

    Full Text Available Under the condition of the plane strain, finite element limit equilibrium method is used to study some key problems of stability analysis for anchored slope. The definition of safe factor in slices method is generalized into FEM. The “true” stress field in the whole structure can be obtained by elastic-plastic finite element analysis. Then, the optimal search for the most dangerous sliding surface with Hooke-Jeeves optimized searching method is introduced. Three cases of stability analysis of natural slope, anchored slope with seepage, and excavation anchored slope are conducted. The differences in safety factor quantity, shape and location of slip surface, anchoring effect among slices method, finite element strength reduction method (SRM, and finite element limit equilibrium method are comparatively analyzed. The results show that the safety factor given by the FEM is greater and the unfavorable slip surface is deeper than that by the slice method. The finite element limit equilibrium method has high calculation accuracy, and to some extent the slice method underestimates the effect of anchor, and the effect of anchor is overrated in the SRM.

  5. LRP1 controls biosynthetic and endocytic trafficking of neuronal prion protein

    DEFF Research Database (Denmark)

    Parkyn, Celia J; Vermeulen, Esmeralda G M; Mootoosamy, Roy C

    2008-01-01

    The trafficking of normal cellular prion protein (PrP(C)) is believed to control its conversion to the altered conformation (designated PrP(Sc)) associated with prion disease. Although anchored to the membrane by means of glycosylphosphatidylinositol (GPI), PrP(C) on neurons is rapidly and consti......The trafficking of normal cellular prion protein (PrP(C)) is believed to control its conversion to the altered conformation (designated PrP(Sc)) associated with prion disease. Although anchored to the membrane by means of glycosylphosphatidylinositol (GPI), PrP(C) on neurons is rapidly...... required for this process. Moreover, sustained inhibition of LRP1 levels by siRNA leads to the accumulation of PrP(C) in biosynthetic compartments, with a concomitant lowering of surface PrP(C), suggesting that LRP1 expedites the trafficking of PrP(C) to the neuronal surface. PrP(C) and LRP1 can be co......-immunoprecipitated from the endoplasmic reticulum in normal neurons. The N-terminal domain of PrP(C) binds to purified human LRP1 with nanomolar affinity, even in the presence of 1 microM of the LRP-specific chaperone, receptor-associated protein (RAP). Taken together, these data argue that LRP1 controls both the surface...

  6. A novel germline PIGA mutation in Ferro-Cerebro-Cutaneous syndrome: a neurodegenerative X-linked epileptic encephalopathy with systemic iron-overload.

    Science.gov (United States)

    Swoboda, Kathryn J; Margraf, Rebecca L; Carey, John C; Zhou, Holly; Newcomb, Tara M; Coonrod, Emily; Durtschi, Jacob; Mallempati, Kalyan; Kumanovics, Attila; Katz, Ben E; Voelkerding, Karl V; Opitz, John M

    2014-01-01

    Three related males presented with a newly recognized x-linked syndrome associated with neurodegeneration, cutaneous abnormalities, and systemic iron overload. Linkage studies demonstrated that they shared a haplotype on Xp21.3-Xp22.2 and exome sequencing was used to identify candidate variants. Of the segregating variants, only a PIGA mutation segregated with disease in the family. The c.328_330delCCT PIGA variant predicts, p.Leu110del (or c.1030_1032delCTT, p.Leu344del depending on the reference sequence). The unaffected great-grandfather shared his X allele with the proband but he did not have the PIGA mutation, indicating that the mutation arose de novo in his daughter. A single family with a germline PIGA mutation has been reported; affected males had a phenotype characterized by multiple congenital anomalies and severe neurologic impairment resulting in infantile lethality. In contrast, affected boys in the family described here were born without anomalies and were neurologically normal prior to onset of seizures after 6 months of age, with two surviving to the second decade. PIGA encodes an enzyme in the GPI anchor biosynthesis pathway. An affected individual in the family studied here was deficient in GPI anchor proteins on granulocytes but not erythrocytes. In conclusion, the PIGA mutation in this family likely causes a reduction in GPI anchor protein cell surface expression in various cell types, resulting in the observed pleiotropic phenotype involving central nervous system, skin, and iron metabolism. © 2013 Wiley Periodicals, Inc.

  7. An enzyme-linked immunosorbent assay for measuring GPIHBP1 levels in human plasma or serum

    DEFF Research Database (Denmark)

    Miyashita, Kazuya; Fukamachi, Isamu; Nagao, Manabu

    2018-01-01

    Background: Glycosylphosphatidylinositol-anchored high-density lipoprotein-binding protein 1 (GPIHBP1), a glycosylphosphatidylinositol (GPI)-anchored protein of capillary endothelial cells, transports lipoprotein lipase to the capillary lumen and is essential for the lipolytic processing of trigl...

  8. Comprehensive evaluation of Streptococcus sanguinis cell wall-anchored proteins in early infective endocarditis.

    Science.gov (United States)

    Turner, Lauren Senty; Kanamoto, Taisei; Unoki, Takeshi; Munro, Cindy L; Wu, Hui; Kitten, Todd

    2009-11-01

    Streptococcus sanguinis is a member of the viridans group of streptococci and a leading cause of the life-threatening endovascular disease infective endocarditis. Initial contact with the cardiac infection site is likely mediated by S. sanguinis surface proteins. In an attempt to identify the proteins required for this crucial step in pathogenesis, we searched for surface-exposed, cell wall-anchored proteins encoded by S. sanguinis and then used a targeted signature-tagged mutagenesis (STM) approach to evaluate their contributions to virulence. Thirty-three predicted cell wall-anchored proteins were identified-a number much larger than those found in related species. The requirement of each cell wall-anchored protein for infective endocarditis was assessed in the rabbit model. It was found that no single cell wall-anchored protein was essential for the development of early infective endocarditis. STM screening was also employed for the evaluation of three predicted sortase transpeptidase enzymes, which mediate the cell surface presentation of cell wall-anchored proteins. The sortase A mutant exhibited a modest (approximately 2-fold) reduction in competitiveness, while the other two sortase mutants were indistinguishable from the parental strain. The combined results suggest that while cell wall-anchored proteins may play a role in S. sanguinis infective endocarditis, strategies designed to interfere with individual cell wall-anchored proteins or sortases would not be effective for disease prevention.

  9. Quantitative evaluation of Candia antarctica lipase B displayed on the cell surface of a Pichia pastoris based on an FS anchor system.

    Science.gov (United States)

    Liang, Xing-xiang; Wang, Bei-bei; Sun, Yu-fei; Lin, Ying; Han, Shuang-yan; Zheng, Sui-ping; Cui, Tang-bing

    2013-03-01

    A new approach is described to quantify the number of enzyme molecules, such as Candia antarctica lipase B, that are displayed on the cell surface of Pichia pastoris. Enhanced green fluorescent protein (EGFP) and Candida antarctica lipase B (CALB) were fused and displayed on the surface of P. pastoris by linking to the anchor flocculation functional domain of FLO1p from Saccharomyces cerevisiae. Confocal laser scanning microscopy, flow cytometry, and fluorescence spectrophotometry were used to monitor the fluorescence intensity of fused EGFP. Combined with the corresponding protein concentration detected in the medium, a standard curve describing the relationship between the fusion protein concentration and fluorescence intensity were obtained and could be used to number CALB displayed on the cell surface. The results showed that approx. 10(4) molecules of CALB molecules were immobilized on the single P. pastoris cell wall based on FS anchor system.

  10. The Ogden Anchor.

    Science.gov (United States)

    Knudson, W E; Cerniglia, M W; Carro, A

    1998-06-01

    Many procedures performed by podiatric surgeons today require the use of a soft-tissue anchoring device. In recent years, many new anchoring devices have become available for use in the foot and ankle. The authors introduce a new soft-tissue anchoring device that has yet to be described in the podiatric literature and present two cases in which the new anchor was used.

  11. Discovery of ebselen as an inhibitor of Cryptosporidium parvum glucose-6-phosphate isomerase (CpGPI) by high-throughput screening of existing drugs.

    Science.gov (United States)

    Eltahan, Rana; Guo, Fengguang; Zhang, Haili; Xiang, Lixin; Zhu, Guan

    2018-04-01

    Cryptosporidium parvum is a water-borne and food-borne apicomplexan pathogen. It is one of the top four diarrheal-causing pathogens in children under the age of five in developing countries, and an opportunistic pathogen in immunocompromised individuals. Unlike other apicomplexans, C. parvum lacks Kreb's cycle and cytochrome-based respiration, thus relying mainly on glycolysis to produce ATP. In this study, we characterized the primary biochemical features of the C. parvum glucose-6-phosphate isomerase (CpGPI) and determined its Michaelis constant towards fructose-6-phosphate (K m  = 0.309 mM, V max  = 31.72 nmol/μg/min). We also discovered that ebselen, an organoselenium drug, was a selective inhibitor of CpGPI by high-throughput screening of 1200 known drugs. Ebselen acted on CpGPI as an allosteric noncompetitive inhibitor (IC 50  = 8.33 μM; K i  = 36.33 μM), while complete inhibition of CpGPI activity was not achieved. Ebselen could also inhibit the growth of C. parvum in vitro (EC 50  = 165 μM) at concentrations nontoxic to host cells, albeit with a relatively small in vitro safety window of 4.2 (cytotoxicity TC 50 on HCT-8 cells = 700 μM). Additionally, ebselen might also target other enzymes in the parasite, leading to the parasite growth reduction. Therefore, although ebselen is useful in studying the inhibition of CpGPI enzyme activity, further proof is needed to chemically and/or genetically validate CpGPI as a drug target. Copyright © 2018 The Authors. Published by Elsevier Ltd.. All rights reserved.

  12. GPi oscillatory activity differentiates tics from the resting state, voluntary movements, and the unmedicated parkinsonian state

    Directory of Open Access Journals (Sweden)

    Joohi Jimenez-Shahed

    2016-09-01

    Full Text Available Background: Deep brain stimulation (DBS is an emerging treatment strategy for severe, medication-refractory Tourette syndrome (TS. Thalamic (Cm-Pf and pallidal (including globus pallidus interna, GPi targets have been the most investigated. While the neurophysiological correlates of Parkinson’s disease (PD in the GPi and subthalamic nucleus (STN are increasingly recognized, these patterns are not well characterized in other disease states. Recent findings indicate that the cross-frequency coupling (CFC between beta band and high frequency oscillations (HFOs within the STN in PD patients is pathologic. Methods: We recorded intraoperative local field potentials (LFPs from the postero-ventrolateral GPi in three adult patients with TS at rest, during voluntary movements, and during tic activity and compared them to the intraoperative GPi-LFP activity recorded from four unmedicated PD patients at rest. Results: In all PD patients, we noted excessive beta band activity (13-30Hz at rest which consistently modulated the amplitude of the co-existent HFOs observed between 200-400Hz, indicating the presence of beta-HFO CFC. In all 3 TS patients at rest, we observed theta band activity (4-7Hz and HFOs. Two patients had beta band activity, though at lower power than theta oscillations. Tic activity was associated with increased high frequency (200-400Hz and gamma band (35-200Hz activity. There was no beta-HFO CFC in TS patients at rest. However, CFC between the phase of 5-10Hz band activity and the amplitude of HFOs was found in two TS patients. During tics, this shifted to CFC between the phase of beta band activity and the amplitude of HFOs in all subjects. Conclusions: To our knowledge this is the first study that shows that beta-HFO CFC exists in the GPi of TS patients during tics and at rest in PD patients, and suggests that this pattern might be specific to pathologic/involuntary movements. Furthermore, our findings suggest that during tics, resting

  13. Effects of STN and GPi deep brain stimulation on impulse control disorders and dopamine dysregulation syndrome.

    Directory of Open Access Journals (Sweden)

    Sarah J Moum

    Full Text Available Impulse control disorders (ICDs and dopamine dysregulation syndrome (DDS are important behavioral problems that affect a subpopulation of patients with Parkinson's disease (PD and typically result in markedly diminished quality of life for patients and their caregivers. We aimed to investigate the effects of subthalamic nucleus (STN and internal globus pallidus (GPi deep brain stimulation (DBS on ICD/DDS frequency and dopaminergic medication usage.A retrospective chart review was performed on 159 individuals who underwent unilateral or bilateral PD DBS surgery in either STN or GPi. According to published criteria, pre- and post-operative records were reviewed to categorize patients both pre- and post-operatively as having ICD, DDS, both ICD and DDS, or neither ICD nor DDS. Group differences in patient demographics, clinical presentations, levodopa equivalent dose (LED, and change in diagnosis following unilateral/bilateral by brain target (STN or GPi DBS placement were examined.28 patients met diagnostic criteria for ICD or DDS pre- or post-operatively. ICD or DDS classification did not differ by GPi or STN target stimulation. There was no change in DDS diagnosis after unilateral or bilateral stimulation. For ICD, diagnosis resolved in 2 of 7 individuals after unilateral or bilateral DBS. Post-operative development of these syndromes was significant; 17 patients developed ICD diagnoses post-operatively with 2 patients with pre-operative ICD developing DDS post-operatively.Unilateral or bilateral DBS did not significantly treat DDS or ICD in our sample, even though a few cases of ICD resolved post-operatively. Rather, our study provides preliminary evidence that DDS and ICD diagnoses may emerge following DBS surgery.

  14. Hemoglobinúria paroxística noturna: relato de dois casos Paroxysmal nocturnal hemoglobinuria: two case reports

    Directory of Open Access Journals (Sweden)

    Carlos J. Araújo

    2002-12-01

    Full Text Available A Hemoglobina Paroxística Noturna (HPN é uma doença adquirida da stem cell hematopoética caracterizada por anemia hemolítica crônica, episódios trombóticos, e com freqüência pancitopenia. É uma desordem clonal, causada por mutação somática do gene PIG-A ligado ao cromossomo X, o qual é requisitado para a formação da estrutura da âncora glicosil-fosfatidil-inositol (GPI. A deficiência da GPI ancorada á proteína CD59 explica a hemólise intravascular na PNH, resultando da inabilidade dos eritrócitos inativar a superfície do complemento. Uma imensa relação clínica existe entre HPN e a anemia aplástica (AA. A ausência de GPI ancorada às proteínas é facilmente detectada pelos métodos de citometria de fluxo aplicados aos eritrócitos e leucócitos; os testes de Ham a da sucrose são absolutos. Em algumas vezes o tratamento com corticóides e/ou androgênio é útil. O transplante de medula óssea alogênico é curativo. O objetivo deste artigo é relatar dois casos de HPN com revisão, enfatizando os aspectos fisiopatológicos, clínicos, diagnósticos e tratamento da HPN.Paroxysmal nocturnal hemoglobinuria (PNH is an acquired hematopoietic stem cell disease characterized by chronic hemolytic anemia, thrombotic episodes and often pancytopenia. It is a chronic disorder caused by a somatic mutation of the X-linked gene PIG-A, which is required for formation of the glycosylphosphatidylinositols (GPI - anchor structure. Deficiency of the GPI-anchored protein CD59 explains intravascular hemolysis in PNH, which results from the inability of erythrocytes to inactivate the surface complement. A very strong clinical relationship exists between aplastic anemia (AA and PNH. Absence of GPI-anchored proteins is easily detected by flow cytometric methods applied to both erythrocytes and leukocytes; the Ham and sucrose tests are now obsolete. Treatment with glucocorticoids and / or androgen is sometimes helpful. Allogeneic

  15. CFD study of the thermal transfer of a non-Newtonian fluid within a tank mechanically stirred by an anchor-shaped impeller

    Science.gov (United States)

    Rahmani, L.; Seghier, O.; Benmoussa, A.; Draoui, B.

    2018-06-01

    The most of operations of chemical, biochemical or petrochemical industries are carried out in tanks or in reactors which are mechanically-controlled. The optimum mode of operation of these devices requires a finalized knowledge of the thermo-hydrodynamic behavior induced by the agitator. In the present work, the characterization of the incompressible hydrodynamic and thermal fields of a non-Newtonian fluid (Bingham) in a flat, non-baffled cylindrical vessel fitted with anchor agitator was undertaken by numerical simulation, using the CFD code Fluent (6.3.26) based on the finite volume discretization method of the energy equation and the Navier-Stokes equations which are formulated in (U.V.P) variables. We have summarized this simulated system by comparing of the consumed power and the Nusselt number for this type of mobile (Anchor agitator).

  16. Optimal suture anchor direction in arthroscopic lateral ankle ligament repair.

    Science.gov (United States)

    Yoshimura, Ichiro; Hagio, Tomonobu; Noda, Masahiro; Kanazawa, Kazuki; Minokawa, So; Yamamoto, Takuaki

    2017-05-26

    In this study, the distance between the insertion point of the suture anchors and posterior surface of the fibula during arthroscopic lateral ankle ligament repair was investigated on computed tomography (CT) images. The hypothesis of this study was that there is an optimal insertional direction of the suture anchor to avoid anchor-related complications. One hundred eleven ankles of 98 patients who had undergone three-dimensional CT scans for foot or ankle disorders without deformity of the fibula were assessed (59 males, 52 females; median age 25.5 years; age range 12-78 years). The shortest distance from the insertion point of the suture anchor to the deepest point of the fossa/top of the convex aspect of the fibula was measured on the axial plane, tilting from the longitudinal axis of the fibula at 90°, 75°, 60°, and 45°. The distance from the insertion point of the suture anchor to the posterior surface of the fibula was also measured in a direction parallel to the sagittal plane of the lateral surface of the talus on the axial plane, tilting from the longitudinal axis of the fibula at 90°, 75°, 60°, and 45°. The posterior fossa was observed in all cases on the 90° and 75° images. The distance from the insertion point to the posterior surface of the fibula in the parallel direction was 15.0 ± 3.4 mm at 90°, 17.5 ± 3.2 mm at 75°, 21.7 ± 3.3 mm at 60°, and 25.7 ± 3.6 mm at 45°. The posterior points in the parallel direction were located on the posterior fossa in 36.0% of cases at 90°, in 12.6% at 75°, and in 0.0% at 60° and 45°. The suture anchor should be directed from anterior to posterior at an angle of <45° to the longitudinal axis of the fibula, parallel to the lateral surface of the talus, to avoid passing through the fibula. Cohort study, Level III.

  17. UPLC-MS/MS based diagnostics for epithelial ovarian cancer using fully sialylated C4-binding protein.

    Science.gov (United States)

    Tanabe, Kazuhiro; Matsuo, Koji; Miyazawa, Masaki; Hayashi, Masaru; Ikeda, Masae; Shida, Masako; Hirasawa, Takeshi; Sho, Ryuichiro; Mikami, Mikio

    2018-05-01

    Serum levels of fully sialylated C4-binding protein (FS-C4BP) are remarkably elevated in patients with epithelial ovarian cancer (EOC) and can be used as a marker to distinguish ovarian clear cell carcinoma from endometrioma. This study aimed to develop a stable, robust and reliable liquid chromatography-hybrid mass spectrometry (UPLC-MS/MS) based diagnostic method that would generalize FS-C4BP as a clinical EOC biomarker. Glycopeptides derived from 20 μL of trypsin-digested serum glycoprotein were analyzed via UPLC equipped with an electrospray ionization time-of-flight mass spectrometer. This UPLC-MS/MS-based diagnostic method was optimized for FS-C4BP and validated using sera from 119 patients with EOC and 127 women without cancer. A1958 (C4BP peptide with two fully sialylated biantennary glycans) was selected as a marker of FS-C4BP because its level in serum was highest among FS-C4BP family members. Preparation and UPLC-MS/MS were optimized for A1958, and performance and robustness were significantly improved relative to our previous method. An area under the curve analysis of the FS-C4BP index receiver operating characteristic curve revealed that the ratio between A1958 and A1813 (C4BP peptide with two partially sialylated biantennary glycans) reached 85%. A combination of the FS-C4BP index and carbohydrate antigen-125 levels further enhanced the sensitivity and specificity. © 2017 The Authors. Biomedical Chromatography published by John Wiley & Sons Ltd.

  18. Comprehensive Evaluation of Streptococcus sanguinis Cell Wall-Anchored Proteins in Early Infective Endocarditis▿ †

    Science.gov (United States)

    Turner, Lauren Senty; Kanamoto, Taisei; Unoki, Takeshi; Munro, Cindy L.; Wu, Hui; Kitten, Todd

    2009-01-01

    Streptococcus sanguinis is a member of the viridans group of streptococci and a leading cause of the life-threatening endovascular disease infective endocarditis. Initial contact with the cardiac infection site is likely mediated by S. sanguinis surface proteins. In an attempt to identify the proteins required for this crucial step in pathogenesis, we searched for surface-exposed, cell wall-anchored proteins encoded by S. sanguinis and then used a targeted signature-tagged mutagenesis (STM) approach to evaluate their contributions to virulence. Thirty-three predicted cell wall-anchored proteins were identified—a number much larger than those found in related species. The requirement of each cell wall-anchored protein for infective endocarditis was assessed in the rabbit model. It was found that no single cell wall-anchored protein was essential for the development of early infective endocarditis. STM screening was also employed for the evaluation of three predicted sortase transpeptidase enzymes, which mediate the cell surface presentation of cell wall-anchored proteins. The sortase A mutant exhibited a modest (∼2-fold) reduction in competitiveness, while the other two sortase mutants were indistinguishable from the parental strain. The combined results suggest that while cell wall-anchored proteins may play a role in S. sanguinis infective endocarditis, strategies designed to interfere with individual cell wall-anchored proteins or sortases would not be effective for disease prevention. PMID:19703977

  19. Anchoring submersible ultrasonic receivers in river channels with stable substrate

    Science.gov (United States)

    Bettoli, Phillip William; Scholten, G.D.; Hubbs, D.

    2010-01-01

    We developed an anchoring system for submersible ultrasonic receivers (SURs) that we placed on the bottom of the riverine reaches of three main-stem reservoirs in the upper Tennessee River. Each anchor consisted of a steel tube (8.9 x 35.6 cm) welded vertically to a round plate of steel (5.1 x 40.6 cm). All seven SURs and their 57-kg anchors were successfully deployed and retrieved three times over 547 d by a dive team employing surface air-breathing equipment and a davit-equipped boat. All of the anchors and their SURs remained stationary over two consecutive winters on the hard-bottom, thalweg sites where they were deployed. The SUR and its anchor at the most downriver site experienced flows that exceeded 2,100 m(3)/s and mean water column velocities of about 0.9 m/s.

  20. Stability calculation method of slope reinforced by prestressed anchor in process of excavation.

    Science.gov (United States)

    Li, Zhong; Wei, Jia; Yang, Jun

    2014-01-01

    This paper takes the effect of supporting structure and anchor on the slope stability of the excavation process into consideration; the stability calculation model is presented for the slope reinforced by prestressed anchor and grillage beam, and the dynamic search model of the critical slip surface also is put forward. The calculation model of the optimal stability solution of each anchor tension of the whole process is also given out, through which the real-time analysis and checking of slope stability in the process of excavation can be realized. The calculation examples indicate that the slope stability is changed with the dynamic change of the design parameters of anchor and grillage beam. So it is relatively more accurate and reasonable by using dynamic search model to determine the critical slip surface of the slope reinforced by prestressed anchor and grillage beam. Through the relationships of each anchor layout and the slope height of various stages of excavation, and the optimal stability solution of prestressed bolt tension design value in various excavation stages can be obtained. The arrangement of its prestressed anchor force reflects that the layout of the lower part of bolt and the calculation of slope reinforcement is in line with the actual. These indicate that the method is reasonable and practical.

  1. Transforming growth factor beta receptor 2 (TGFBR2 changes sialylation in the microsatellite unstable (MSI Colorectal cancer cell line HCT116.

    Directory of Open Access Journals (Sweden)

    Jennifer Lee

    Full Text Available Aberrant glycosylation is a common feature of many malignancies including colorectal cancers (CRCs. About 15% of CRC show the microsatellite instability (MSI phenotype that is associated with a high frequency of biallelic frameshift mutations in the A10 coding mononucleotide microsatellite of the transforming growth factor beta receptor 2 (TGFBR2 gene. If and how impaired TGFBR2 signaling in MSI CRC cells affects cell surface glycan pattern is largely unexplored. Here, we used the TGFBR2-deficient MSI colon carcinoma cell line HCT116 as a model system. Stable clones conferring doxycycline (dox-inducible expression of a single copy wildtype TGFBR2 transgene were generated by recombinase-mediated cassette exchange (RMCE. In two independent clones, dox-inducible expression of wildtype TGFBR2 protein and reconstitution of its signaling function was shown. Metabolic labeling experiments using the tritiated sialic acid precursor N-acetyl-D-mannosamine (ManNAc revealed a significant decline (∼30% of its incorporation into newly synthesized sialoglycoproteins in a TGFBR2-dependent manner. In particular, we detected a significant decrease of sialylated ß1-integrin upon reconstituted TGFBR2 signaling which did not influence ß1-integrin protein turnover. Notably, TGFBR2 reconstitution did not affect the transcript levels of any of the known human sialyltransferases when examined by real-time RT- PCR analysis. These results suggest that reconstituted TGFBR2 signaling in an isogenic MSI cell line model system can modulate sialylation of cell surface proteins like ß1-integrin. Moreover, our model system will be suitable to uncover the underlying molecular mechanisms of altered MSI tumor glycobiology.

  2. Functionalized Nanostructures: Redox-Active Porphyrin Anchors for Supramolecular DNA Assemblies

    KAUST Repository

    Börjesson, Karl

    2010-09-28

    We have synthesized and studied a supramolecular system comprising a 39-mer DNA with porphyrin-modified thymidine nucleosides anchored to the surface of large unilamellar vesicles (liposomes). Liposome porphyrin binding characteristics, such as orientation, strength, homogeneity, and binding site size, was determined, suggesting that the porphyrin is well suited as a photophysical and redox-active lipid anchor, in comparison to the inert cholesterol anchor commonly used today. Furthermore, the binding characteristics and hybridization capabilities were studied as a function of anchor size and number of anchoring points, properties that are of importance for our future plans to use the addressability of these redox-active nodes in larger DNA-based nanoconstructs. Electron transfer from photoexcited porphyrin to a lipophilic benzoquinone residing in the lipid membrane was characterized by steady-state and time-resolved fluorescence and verified by femtosecond transient absorption. © 2010 American Chemical Society.

  3. Post-installed concrete anchors in nuclear power plants: Performance and qualification

    International Nuclear Information System (INIS)

    Mahrenholtz, Philipp; Eligehausen, Rolf

    2015-01-01

    Graphical abstract: - Highlights: • Review of qualification and design regulations for anchors in nuclear power plants. • First complete set of nuclear anchor load–displacement data and its evaluation ever. • Demonstration of robust test behavior of a qualified post-installed anchor product. - Abstract: In nuclear power plants (NPPs), post-installed anchors are widely used for structural and non-structural connections to concrete. In many countries, anchor products employed for safety relevant applications have to be approved by the authorities. For the high safety standards in force for NPPs, special requirements have to be met to allow for extreme design situations. This paper presents an experimental test program conducted to evaluate the performance of anchors according to the German Guideline for Anchorages in Nuclear Power Plants and Nuclear Technology Installations (DIBt KKW Leitfaden, 2010). After a brief introduction to anchor behavior and the regulative context, the results of tension and shear tests carried out on undercut anchors are discussed. Robust load capacities and relatively small displacements determined for demanding load and crack cycling tests demonstrated the suitability of anchors qualified according to a state-of-the-art qualification guideline

  4. Blood Plasma-Derived Anti-Glycan Antibodies to Sialylated and Sulfated Glycans Identify Ovarian Cancer Patients.

    Science.gov (United States)

    Pochechueva, Tatiana; Chinarev, Alexander; Schoetzau, Andreas; Fedier, André; Bovin, Nicolai V; Hacker, Neville F; Jacob, Francis; Heinzelmann-Schwarz, Viola

    2016-01-01

    Altered levels of naturally occurring anti-glycan antibodies (AGA) circulating in human blood plasma are found in different pathologies including cancer. Here the levels of AGA directed against 22 negatively charged (sialylated and sulfated) glycans were assessed in high-grade serous ovarian cancer (HGSOC, n = 22) patients and benign controls (n = 31) using our previously developed suspension glycan array (SGA). Specifically, the ability of AGA to differentiate between controls and HGSOC, the most common and aggressive type of ovarian cancer with a poor outcome was determined. Results were compared to CA125, the commonly used ovarian cancer biomarker. AGA to seven glycans that significantly (P<0.05) differentiated between HGSOC and control were identified: AGA to top candidates SiaTn and 6-OSulfo-TF (both IgM) differentiated comparably to CA125. The area under the curve (AUC) of a panel of AGA to 5 glycans (SiaTn, 6-OSulfo-TF, 6-OSulfo-LN, SiaLea, and GM2) (0.878) was comparable to CA125 (0.864), but it markedly increased (0.985) when combined with CA125. AGA to SiaTn and 6-OSulfo-TF were also valuable predictors for HGSOC when CA125 values appeared inconclusive, i.e. were below a certain threshold. AGA-glycan binding was in some cases isotype-dependent and sensitive to glycosidic linkage switch (α2-6 vs. α2-3), to sialylation, and to sulfation of the glycans. In conclusion, plasma-derived AGA to sialylated and sulfated glycans including SiaTn and 6-OSulfo-TF detected by SGA present a valuable alternative to CA125 for differentiating controls from HGSOC patients and for predicting the likelihood of HGSOC, and may be potential HGSOC tumor markers.

  5. AnchorDock for Blind Flexible Docking of Peptides to Proteins.

    Science.gov (United States)

    Slutzki, Michal; Ben-Shimon, Avraham; Niv, Masha Y

    2017-01-01

    Due to increasing interest in peptides as signaling modulators and drug candidates, several methods for peptide docking to their target proteins are under active development. The "blind" docking problem, where the peptide-binding site on the protein surface is unknown, presents one of the current challenges in the field. AnchorDock protocol was developed by Ben-Shimon and Niv to address this challenge.This protocol narrows the docking search to the most relevant parts of the conformational space. This is achieved by pre-folding the free peptide and by computationally detecting anchoring spots on the surface of the unbound protein. Multiple flexible simulated annealing molecular dynamics (SAMD) simulations are subsequently carried out, starting from pre-folded peptide conformations, constrained to the various precomputed anchoring spots.Here, AnchorDock is demonstrated using two known protein-peptide complexes. A PDZ-peptide complex provides a relatively easy case due to the relatively small size of the protein, and a typical peptide conformation and binding region; a more challenging example is a complex between USP7 N-term and a p53-derived peptide, where the protein is larger, and the peptide conformation and a binding site are generally assumed to be unknown. AnchorDock returned native-like solutions ranked first and third for the PDZ and USP7 complexes, respectively. We describe the procedure step by step and discuss possible modifications where applicable.

  6. Photoactive curcumin-derived dyes with surface anchoring moieties used in ZnO nanoparticle-based dye-sensitized solar cells

    International Nuclear Information System (INIS)

    Ganesh, T.; Kim, Jong Hoon; Yoon, Seog Joon; Kil, Byung-Ho; Maldar, N.N.; Han, Jin Wook; Han, Sung-Hwan

    2010-01-01

    Photoactive, eco-friendly and high molar extinction coefficient, curcumin-derived dyes (BCMoxo and BCtCM) have been explored in ZnO nanoparticles (NPs)-based dye-sensitized solar cells (DSSCs). The boron complex curcumin dyes modified with di-carboxylic anchor groups (BCtCM) provided surface attachment with a strong UV-vis region absorption than the dye molecule without anchor groups (BCMoxo). Photoanodes primed with poly-dispersive ZnO NPs (∼80-50 nm) specifically devised for these dyes and optimized for the critical thickness, sensitization time and concentration using a solvent-free ionic electrolyte so as to get current density as high as 1.66 mA/cm 2 under 80 mW/cm 2 irradiation. Therefore, a successful conversion of visible light into electricity by using these curcumin-derived dyes (natural derived photoactive molecules) as photosensitizer in DSSCs would be a great interest in future studies for enhancing further conversion efficiencies.

  7. Surface modified liposomes by mannosylated conjugates anchored via the adamantyl moiety in the lipid bilayer.

    Science.gov (United States)

    Stimac, Adela; Segota, Suzana; Dutour Sikirić, Maja; Ribić, Rosana; Frkanec, Leo; Svetličić, Vesna; Tomić, Srđanka; Vranešić, Branka; Frkanec, Ruža

    2012-09-01

    The aim of the present study was to encapsulate mannosylated 1-aminoadamantane and mannosylated adamantyltripeptides, namely [(2R)-N-(adamant-1-yl)-3-(α,β-d-mannopyranosyloxy)-2-methylpropanamide and (2R)-N-[3-(α-d-mannopyranosyloxy)-2-methylpropanoyl]-d,l-(adamant-2-yl)glycyl-l-alanyl-d-isoglutamine] in liposomes. The characterization of liposomes, size and surface morphology was performed using dynamic light scattering (DLS) and atomic force microscopy (AFM). The results have revealed that the encapsulation of examined compounds changes the size and surface of liposomes. After the concanavalin A (ConA) was added to the liposome preparation, increase in liposome size and their aggregation has been observed. The enlargement of liposomes was ascribed to the specific binding of the ConA to the mannose present on the surface of the prepared liposomes. Thus, it has been shown that the adamantyl moiety from mannosylated 1-aminoadamantane and mannosylated adamantyltripeptides can be used as an anchor in the lipid bilayer for carbohydrate moiety exposed on the liposome surface. Copyright © 2012 Elsevier B.V. All rights reserved.

  8. Effect of Bcl-xL overexpression on sialylation of Fc-fusion protein in recombinant Chinese hamster ovary cell cultures.

    Science.gov (United States)

    Lee, Jong Hyun; Kim, Yeon-Gu; Lee, Gyun Min

    2015-01-01

    The sialic acid of glycoproteins secreted by recombinant Chinese hamster ovary (rCHO) cells can be impaired by sialidase under culture conditions which promote the extracellular accumulation of this enzyme. To investigate the effect of Bcl-xL overexpression on the sialylation of glycoproteins produced in rCHO cell culture, two rCHO cell lines producing the same Fc-fusion protein, which were derived from DUKX-B11 and DG44, respectively, were engineered to have regulated Bcl-xL overexpression using the Tet-off system. For both cell lines, Bcl-xL overexpression improved cell viability and extended culture longevity in batch cultures. As a result, a maximum Fc-fusion protein titer increased by Bcl-xL overexpression though the extent of titer enhancement differed between the two cell lines. With Bcl-xL overexpression, the sialylation of Fc-fusion protein, which was assessed by isoelectric focusing gel and sialic acid content analyses, decreased more slowly toward the end of batch cultures. This was because Bcl-xL overexpression delayed the extracellular accumulation of sialidase activity by reducing cell lysis during batch cultures. Taken together, Bcl-xL overexpression in rCHO cell culture increased Fc-fusion protein production and also reduced the impairment of sialylation of Fc-fusion protein by maintaining high viability during batch cultures. © 2015 American Institute of Chemical Engineers.

  9. Fraction A of armadillo submandibular glycoprotein and its desialylated product as sialyl-Tn and Tn receptors for lectins.

    Science.gov (United States)

    Wu, A M; Shen, F; Herp, A; Song, S C; Wu, J H

    1995-02-27

    Fraction A of the armadillo submandibular glycoprotein (ASG-A) is one of the simplest glycoproteins among mammalian salivary mucins. The carbohydrate side chains of this mucous glycoprotein have one-third of the NeuAc alpha 2-->6GalNAc (sialyl-Tn) sequence and two thirds of Tn (GalNAc alpha-->Ser/Thr) residues. Those of the desialylated product (ASG-Tn) are almost exclusively unsubstituted GalNAc residues (Tn determinant). When the binding properties of these glycoproteins were tested by a precipitin assay with Gal, GalNAc and GlcNAc specific lectins, it was found that ASG-Tn reacted strongly with all of the Tn-active lectins and completely precipitated Vicia villosa (VVL both B4 and mixture of A and B), Maclura pomifera (MPA), and Artocarpus integrifolia (jacalin) lectins. However, it precipitated poorly or negligibly with Ricinus communis (RCA1); Dolichos biflorus (DBA); Viscum album, ML-I; Arachis hypogaea (PNA), and Triticum vulgaris (WGA). The reactivity of ASG-A (sialyl-Tn) was as active as that of ASG-Tn with MPA and less or slightly less active than that of ASG-Tn with VVL-A+B, VVL-B4, HPA, WFA, and jacalin, as one-third of its Tn was sialylated. These findings indicate that ASG-A and its desialylated product (ASG-Tn) are highly useful reagents for the differentiation of Tn, T (Gal beta 1-->3GalNAc), A (GalNAc alpha 1-->3Gal) or Gal specific lectins and monoclonal antibodies against such epitopes.

  10. Influence of weak anchoring upon the alignment of smectic A liquid crystals with surface pretilt

    International Nuclear Information System (INIS)

    De Vita, R; Stewart, I W

    2008-01-01

    Equilibrium configurations for smectic A liquid crystals in a 'bookshelf' geometry are determined from a nonlinear continuum model under strong and weak anchoring conditions at the boundary for the usual director n. Natural boundary conditions are derived for n and the smectic layer normal a when a preferred director orientation n p , which generally induces a director pretilt, is prescribed on the boundaries. Two key aspects are examined via the nonlinear equilibrium equations: the separation of n from a and the influence of weak anchoring. The orientations of n and a relative to n p may differ significantly and depend very much upon the magnitude of the anchoring strength. These results from a nonlinear theory are natural and novel developments of previous classical linearized models for which n ≡ a. Comparisons are also drawn between solutions for strong and weak anchoring conditions

  11. Clinical roundtable monograph: Paroxysmal nocturnal hemoglobinuria: a case-based discussion.

    Science.gov (United States)

    Szer, Jeff; Hill, Anita; Weitz, Ilene Ceil

    2012-11-01

    Paroxysmal nocturnal hemoglobinuria (PNH) is a rare, acquired disorder characterized by chronic intravascular hemolysis as the primary clinical manifestation and morbidities that include anemia, thrombosis, renal impairment, pulmonary hypertension, and bone marrow failure. The prevalence of the PNH clone (from <1-100% PNH granulocytes) is approximately 16 per million, and careful monitoring is required. The average age of onset of the clinical disease is the early 30s, although it can present at all ages. PNH is caused by the acquisition of a somatic mutation of the gene phosphatidylinositol glycan anchor (PIG-A) in a multipotent hematopoietic stem cell (HSC), with clonal expansion of the mutated HSC. The mutation causes a deficiency in the synthesis of glycosylphosphatidylinositol (GPI). In cells derived from normal HSCs, the complement regulatory proteins CD55 and CD59 are anchored to the hematopoietic cell membrane surface via GPI, protecting the cells from complement-mediated lysis. However, in patients with PNH, these 2 proteins, along with numerous other GPI-linked proteins, are absent from the cell surface of red cells, granulocytes, monocytes, and platelets, resulting in complement-mediated intravascular hemolysis and other complications. Lysis of red blood cells is the most obvious manifestation, but as other cell lineages are also affected, this complement-mediated attack contributes to additional complications, such as thrombosis. Eculizumab, a humanized monoclonal antibody against the C5 complement protein, is the only effective drug therapy for PNH patients. The antibody prevents cleavage of the C5 protein by C5 convertase, in turn preventing generation of C5b-9 and release of C5a, thereby protecting from hemolysis of cells lacking the CD59 surface protein and other complications associated with complement activation. Drs. Ilene C. Weitz, Anita Hill, and Jeff Szer discuss 3 recent cases of patients with PNH.

  12. Ultraweak azimuthal anchoring of a nematic liquid crystal on a planar orienting photopolymer

    International Nuclear Information System (INIS)

    Nespoulous, Mathieu; Blanc, Christophe; Nobili, Maurizio

    2007-01-01

    The search of weak anchoring is an important issue for a whole class of liquid crystal displays. In this paper we present an orienting layer showing unreached weak planar azimuthal anchoring for 4-n-pentyl-4 ' -cyanobiphenyl nematic liquid crystal (5CB). Azimuthal extrapolation lengths as large as 80 μm are easily obtained. Our layers are made with the commercial photocurable polymer Norland optical adhesive 60. The anisotropy of the film is induced by the adsorption of oriented liquid crystal molecules under a 2 T magnetic field applied parallel to the surfaces. We use the width of surface π-walls and a high-field electro-optical method to measure, respectively, the azimuthal and the zenithal anchorings. The azimuthal anchoring is extremely sensitive to the ultraviolet (UV) dose and it also depends on the magnetic field application duration. On the opposite, the zenithal anchoring is only slightly sensitive to the preparation parameters. All these results are discussed in terms of the adsorption/desorption mechanisms of the liquid crystal molecules on the polymer layer and of the flexibility of the polymer network

  13. Anchor Bolt Position in Base Plate In Terms Of T and J Anchor Bolt

    Directory of Open Access Journals (Sweden)

    b Osman Mohamad Hairi

    2017-01-01

    Full Text Available Generally, L anchor bolt system has been used for a long period of time in construction industry as one of the distributing load structures. However, there are some weaknesses in L anchor bolt which may straighten and pullup when charged with tensile load. Current practices prefer to use other types of anchor bolt systems, such as headed studs anchor bolt system to replace the L anchor bolt design. There has been lack of studies to prove that it is more effective in terms of performance. A new T anchor bolt which was basically modified from headed studs anchor bolt was proposed in this study to compare its performance of tensile loading in concrete failure to typical L design. This study aims to determine whether the T anchor bolt system gives better performance as compared to an L anchor bolt system. The performance was rated based on tensile loading on concrete failure pattern. A pullout test was conducted on two different anchor bolt systems, namely L and T. The anchor bolt embedded depth, h in concrete were varied according to their hook or bend radius. Each sample was repeated twice. There were totally eight samples. The hook or bend radius used were 50 mm and 57.5 mm for sample L1 and L2, respectively. 90-degree bend were used on sample T1 and T2. Based on test results, it can be seen that the performance of concrete failure pattern under tensile load on both L and T anchor bolt design samples with 200 mm embedment depth was better than deeper embedment depth of 230 mm. But the L anchor bolt design gives the best results as compared to T design. Although T anchor bolt design shows higher resistance before first bond failure to the concrete sample. T anchor bolt was analysed and needed deeper embedment depth to allow formation of cone pull-out shape to acquire better performance.

  14. Improvement of trans-sialylation versus hydrolysis activity of an engineered sialidase from Trypanosoma rangeli by use of co-solvents

    DEFF Research Database (Denmark)

    Zeuner, Birgitte; Riisager, Anders; Mikkelsen, Jørn Dalgaard

    2014-01-01

    hexafluorophosphate), were examined as co-solvents for the improvement of the synthesis versus hydrolysis ratio in the trans-sialylation of lactose, catalysed by an engineered sialidase from Trypanosoma rangeli. The use of 25 % (v/v) t-butanol as co-solvent significantly increased 3'-sialyllactose production by 40...... % from 1.04 ± 0.09 to 1.47 ± 0.01 mM. The synthesis versus hydrolysis ratio increased correspondingly by 1.2-times. 1-2.5 % (v/v) EAN or [C2OHMIm][PF6] improved the synthesis versus hydrolysis ratio up to 2.5-times but simultaneously decreased the 3'-sialyllactose yield, probably due to enzyme...... inactivation caused by the ionic liquid. [MMIm][MeSO4] had a detrimental effect on the trans-sialylation yield and on the ratio between synthesis and hydrolysis....

  15. Root hairs aid soil penetration by anchoring the root surface to pore walls.

    Science.gov (United States)

    Bengough, A Glyn; Loades, Kenneth; McKenzie, Blair M

    2016-02-01

    The physical role of root hairs in anchoring the root tip during soil penetration was examined. Experiments using a hairless maize mutant (Zea mays: rth3-3) and its wild-type counterpart measured the anchorage force between the primary root of maize and the soil to determine whether root hairs enabled seedling roots in artificial biopores to penetrate sandy loam soil (dry bulk density 1.0-1.5g cm(-3)). Time-lapse imaging was used to analyse root and seedling displacements in soil adjacent to a transparent Perspex interface. Peak anchorage forces were up to five times greater (2.5N cf. 0.5N) for wild-type roots than for hairless mutants in 1.2g cm(-3) soil. Root hair anchorage enabled better soil penetration for 1.0 or 1.2g cm(-3) soil, but there was no significant advantage of root hairs in the densest soil (1.5g cm(-3)). The anchorage force was insufficient to allow root penetration of the denser soil, probably because of less root hair penetration into pore walls and, consequently, poorer adhesion between the root hairs and the pore walls. Hairless seedlings took 33h to anchor themselves compared with 16h for wild-type roots in 1.2g cm(-3) soil. Caryopses were often pushed several millimetres out of the soil before the roots became anchored and hairless roots often never became anchored securely.The physical role of root hairs in anchoring the root tip may be important in loose seed beds above more compact soil layers and may also assist root tips to emerge from biopores and penetrate the bulk soil. © The Author 2016. Published by Oxford University Press on behalf of the Society for Experimental Biology.

  16. Additional Haptic Information Provided by Anchors Reduces Postural Sway in Young Adults Less Than Does Light Touch

    Directory of Open Access Journals (Sweden)

    Renato Moraes

    2018-06-01

    Full Text Available This study investigated the effect of adding haptic information to the control of posture, as well as comparing the effect of both the “light touch” (LT and “anchor system” (AS paradigms on postural sway. Additionally, it compared the effect of location and number of points of contact to the control of posture in young adults. The location consisted of using the anchors tied to the finger and held by the hands, and, for LT, the fingertip. For the number of points of contact, participants used two hands, and then separately the dominant hand, and the non-dominant hand, for both anchor and LT paradigms. Participants stood upright with feet-together and in tandem position while performing tasks that combined the use of anchors and LT, points of contact (hand grip and finger, and number of points of contact (two hands and one hand. In this study, the anchors consist of holding in each hand a flexible cable with the other end attached to the ground. The LT consists of slightly touching a rigid surface with the tip of the index finger. The results showed, first, that the anchors improved postural control less than did the LT. Second, they revealed that holding the anchors with the hands or with them tied to the fingertip resulted in a similar reduction in postural sway only in the tandem position. For the feet-together position, the anchors tied to the fingertip were ineffective. Similarly, the use of one or two hands did not affect the contribution of the anchors. However, using two hands in the LT condition was more effective than was one hand. Third, our results showed the presence of a temporal delay between force and center-of-pressure (COP for the anchors, only in the AP direction with feet-together. In conclusion, overall, the anchors were less effective in reducing postural sway than was the LT. The anchors attached to fingertips were as effective as the hand-held anchors in the tandem position, yet ineffective during foot

  17. Effects of tunicamycin, mannosamine, and other inhibitors of glycoprotein processing on skeletal alkaline phosphatase in human osteoblast-like cells.

    Science.gov (United States)

    Farley, J R; Magnusson, P

    2005-01-01

    Skeletal alkaline phosphatase (sALP) is a glycoprotein- approximately 20% carbohydrate by weight, with five presumptive sites for N-linked glycosylation, as well as a carboxy-terminal site for attachment of the glycolipid structure (glycosylphosphatidylinositol, GPI), which anchors sALP to the outer surface of osteoblasts. The current studies were intended to characterize the effects of inhibiting glycosylation and glycosyl-processing on the synthesis, plasma membrane attachment, cellular-extracellular distribution, and reaction kinetics of sALP in human osteosarcoma (SaOS-2) cells. sALP synthesis, glycosylation, and GPI-anchor attachment were assessed as total protein synthesis/immunospecific sALP synthesis, sialic acid content (i.e., wheat germ agglutinin precipitation), and insolubility (i.e., temperature-dependent phase-separation), respectively. sALP reaction kinetics were characterized by analysis of dose-dependent initial velocity data, with a phosphoryl substrate. The results of these studies revealed that the inhibition of either N-linked glycosylation or oligosaccharide synthesis for GPI-anchor addition could affect the synthesis and the distribution of sALP, but not the kinetics of the phosphatase reaction. Tunicamycin-which blocks N-linked glycosylation by inhibiting core oligosaccharide synthesis-decreased cell layer protein and the total amount of sALP in the cells, while increasing the relative level of sALP in the cell-conditioned culture medium (CM, i.e., the amount of sALP released). These effects were attributed to dose- and time-dependent decreases in sALP synthesis and N-linked glycosylation, and an increase in apoptotic cell death (P sALP specific activity, in the cells and in the CM; and (3) increases in the percentages of both anchorless and wheat germ agglutinin (WGA)-soluble sALP in the medium, but not in the cells (P sALP to the outside of the plasma membrane surface. Neither mannosammine nor tunicamycin had any effect on the reaction

  18. Influence of weak anchoring upon the alignment of smectic A liquid crystals with surface pretilt

    Energy Technology Data Exchange (ETDEWEB)

    De Vita, R [Department of Engineering Science and Mechanics, Virginia Tech, 230 Norris Hall, Blacksburg, VA 24061 (United States); Stewart, I W [Department of Mathematics, University of Strathclyde, Livingstone Tower, 26 Richmond Street, Glasgow G1 1XH (United Kingdom)], E-mail: devita@vt.edu, E-mail: i.w.stewart@strath.ac.uk

    2008-08-20

    Equilibrium configurations for smectic A liquid crystals in a 'bookshelf' geometry are determined from a nonlinear continuum model under strong and weak anchoring conditions at the boundary for the usual director n. Natural boundary conditions are derived for n and the smectic layer normal a when a preferred director orientation n{sub p}, which generally induces a director pretilt, is prescribed on the boundaries. Two key aspects are examined via the nonlinear equilibrium equations: the separation of n from a and the influence of weak anchoring. The orientations of n and a relative to n{sub p} may differ significantly and depend very much upon the magnitude of the anchoring strength. These results from a nonlinear theory are natural and novel developments of previous classical linearized models for which n {identical_to} a. Comparisons are also drawn between solutions for strong and weak anchoring conditions.

  19. A Vehicle Haptic Steering by Wire System Based on High Gain GPI Observers

    Directory of Open Access Journals (Sweden)

    A. Rodriguez-Angeles

    2014-01-01

    Full Text Available A vehicle steering by wire (SBW haptic system based on high gain generalized proportional integral (GPI observers is introduced. The observers are considered for the estimation of dynamic perturbations that are present at the tire and steering wheel. To ensure efficient tracking between the commanded steering wheel angle and the tire orientation angle, the estimated perturbations are on line canceled. As to provide a haptic interface with the driver, the estimated dynamic effects at the steering rack are fed back to the steering wheel, yielding a master-slave haptic system with bilateral communication. For implementation purposes few sensors and minimum knowledge of the dynamic model are required, which is a major advantage compared to other approaches. Only position tracking errors are fed back, while all other signals are estimated by the high gain GPI observers. The scheme is robust to uncertainty on the input gain and cancels dynamic perturbation effects such as friction and aligning forces on the tire. Experimental results are presented on a prototype platform.

  20. Photoactive curcumin-derived dyes with surface anchoring moieties used in ZnO nanoparticle-based dye-sensitized solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Ganesh, T.; Kim, Jong Hoon; Yoon, Seog Joon; Kil, Byung-Ho; Maldar, N.N. [Inorganic Nano-Materials Laboratory, Department of Chemistry, Hanyang University, Sung-Dong-Ku, Haengdang-dong 17, Seoul (Korea, Republic of); Han, Jin Wook, E-mail: jwhan@hanyang.ac.kr [Inorganic Nano-Materials Laboratory, Department of Chemistry, Hanyang University, Sung-Dong-Ku, Haengdang-dong 17, Seoul (Korea, Republic of); Han, Sung-Hwan, E-mail: shhan@hanyang.ac.kr [Inorganic Nano-Materials Laboratory, Department of Chemistry, Hanyang University, Sung-Dong-Ku, Haengdang-dong 17, Seoul (Korea, Republic of)

    2010-09-01

    Photoactive, eco-friendly and high molar extinction coefficient, curcumin-derived dyes (BCMoxo and BCtCM) have been explored in ZnO nanoparticles (NPs)-based dye-sensitized solar cells (DSSCs). The boron complex curcumin dyes modified with di-carboxylic anchor groups (BCtCM) provided surface attachment with a strong UV-vis region absorption than the dye molecule without anchor groups (BCMoxo). Photoanodes primed with poly-dispersive ZnO NPs ({approx}80-50 nm) specifically devised for these dyes and optimized for the critical thickness, sensitization time and concentration using a solvent-free ionic electrolyte so as to get current density as high as 1.66 mA/cm{sup 2} under 80 mW/cm{sup 2} irradiation. Therefore, a successful conversion of visible light into electricity by using these curcumin-derived dyes (natural derived photoactive molecules) as photosensitizer in DSSCs would be a great interest in future studies for enhancing further conversion efficiencies.

  1. Anchored but not internalized: shape dependent endocytosis of nanodiamond

    Science.gov (United States)

    Zhang, Bokai; Feng, Xi; Yin, Hang; Ge, Zhenpeng; Wang, Yanhuan; Chu, Zhiqin; Raabova, Helena; Vavra, Jan; Cigler, Petr; Liu, Renbao; Wang, Yi; Li, Quan

    2017-04-01

    Nanoparticle-cell interactions begin with the cellular uptake of the nanoparticles, a process that eventually determines their cellular fate. In the present work, we show that the morphological features of nanodiamonds (NDs) affect both the anchoring and internalization stages of their endocytosis. While a prickly ND (with sharp edges/corners) has no trouble of anchoring onto the plasma membrane, it suffers from difficult internalization afterwards. In comparison, the internalization of a round ND (obtained by selective etching of the prickly ND) is not limited by its lower anchoring amount and presents a much higher endocytosis amount. Molecular dynamics simulation and continuum modelling results suggest that the observed difference in the anchoring of round and prickly NDs likely results from the reduced contact surface area with the cell membrane of the former, while the energy penalty associated with membrane curvature generation, which is lower for a round ND, may explain its higher probability of the subsequent internalization.

  2. ANTS-anchored Zn-Al-CO3-LDH particles as fluorescent probe for sensing of folic acid

    International Nuclear Information System (INIS)

    Liu, Pengfei; Liu, Dan; Liu, Yanhuan; Li, Lei

    2016-01-01

    A novel fluorescent nanosensor for detecting folic acid (FA) in aqueous media has been developed based on 8-aminonaphthalene-1,3,6-trisulfonate (ANTS) anchored to the surface of Zn-Al-CO 3 -layered double hydroxides (LDH) particles. The nanosensor showed high fluorescence intensity and good photostability due to a strong coordination interaction between surface Zn 2+ ions of Zn-Al-CO 3 -LDH and N atoms of ANTS, which were verified by result of X-ray photoelectron spectroscopy (XPS). ANTS-anchored on the surface of Zn-Al-CO 3 -LDH restricted the intra-molecular rotation leading to ANTS-anchored J-type aggregation emission enhancement. ANTS-anchored Zn-Al-CO 3 -LDH particles exhibited highly sensitive and selective response to FA over other common metal ions and saccharides present in biological fluids. The proposed mechanism was that oxygen atoms of -SO 3 groups in ANTS-anchored on the surface of Zn-Al-CO 3 -LDH were easily collided by FA molecules to form potential hydrogen bonds between ANTS-anchored and FA molecules, which could effectively quench the ANTS-anchored fluorescence. Under the simulated physiological conditions (pH of 7.4), the fluorescence quenching was fitted to Stern-Volmer equation with a linear response in the concentration range of 1 μM to 200 μM with a limit of detection of 0.1 μM. The results indicate that ANTS-anchored Zn-Al-CO 3 -LDH particles can afford a very sensitive system for the sensing FA in aqueous solution. - Highlights: • A novel fluorescent nanosensor has been developed. • The sensor exhibited highly sensitive and selective response to FA. • The fluorescence quenching was fitted to Stern–Volmer equation. • The linear response range was 1–200 μM with a limit of detection of 0.1 μM.

  3. Density control of dodecamanganese clusters anchored on silicon(100).

    Science.gov (United States)

    Condorelli, Guglielmo G; Motta, Alessandro; Favazza, Maria; Nativo, Paola; Fragalà, Ignazio L; Gatteschi, Dante

    2006-04-24

    A synthetic strategy to control the density of Mn12 clusters anchored on silicon(100) was investigated. Diluted monolayers suitable for Mn12 anchoring were prepared by Si-grafting mixtures of the methyl 10-undecylenoate precursor ligand with 1-decene spectator spacers. Different ratios of these mixtures were tested. The grafted surfaces were hydrolyzed to reveal the carboxylic groups available for the subsequent exchange with the [Mn12O12(OAc)16(H2O)4]4 H2O2 AcOH cluster. Modified surfaces were analyzed by attenuated total reflection (ATR)-FTIR spectroscopy, X-ray photoemission spectroscopy (XPS), and AFM imaging. Results of XPS and ATR-FTIR spectroscopy show that the surface mole ratio between grafted ester and decene is higher than in the source solution. The surface density of the Mn12 cluster is, in turn, strictly proportional to the ester mole fraction. Well-resolved and isolated clusters were observed by AFM, using a diluted ester/decene 1:1 solution.

  4. Numerical Simulation of Electro-Mechanical Impedance Response in Cable-Anchor Connection Interface

    International Nuclear Information System (INIS)

    Nguyen, Khac Duy; Kim, Jeong Tae

    2011-01-01

    In this study, a finite element(FE) analysis on electro-mechanical impedance response of cable-anchor connection interface under various anchor force is presented. In order to achieve the objective, the following approaches are implemented. Firstly, an interface washer coupled with piezoelectric(PZT) material is designed for monitoring cable-force loss. The interface washer is a small aluminum plate on which a PZT patch is surface-bonded. Cable-force loss could be monitored by installing the interface washer between the anchor plate and the anchorage of cable-anchor connection and examining the changes of impedance of the interface washer. Secondly, a FE model for cable-anchor connection is established to examine the effect of cable-force on impedance response of interface washer. Also, the effects of geometrical and material properties of the interface washer on impedance responses under various cable-forces are investigated. Finally, validation of the FE analysis is experimentally evaluated by a lab-scale cable-anchor connection

  5. Analysis of Anchoring Mechanism of Fully Grouted Prestressed Anchor

    Directory of Open Access Journals (Sweden)

    WEN Zhi-jie

    2014-01-01

    Full Text Available Some researchers have been carried out on analysis of the influence of the full grouted prestressed anchor shape of borehole wall on its carrying capacity. Based on the self-affine fractal feature of anchor borehole wall structural plane, the relation equation among structural plane shear strength, liquid injection pressure, tensile load and structural plane fractal dimension D was built, the instability judgment criterion of anchoring bearing strata and rock structural plane was determined, the solving equations of disintegrated rock support density were derived. Based on the experimental results, the theoretical basis of support design under the disintegrated rock condition was offered.

  6. Modeling and experimental validation of sawing based lander anchoring and sampling methods for asteroid exploration

    Science.gov (United States)

    Zhang, Jun; Dong, Chengcheng; Zhang, Hui; Li, Song; Song, Aiguo

    2018-05-01

    This paper presents a novel lander anchoring system based on sawing method for asteroid exploration. The system is composed of three robotic arms, three cutting discs, and a control system. The discs mounted at the end of the arms are able to penetrate into the rock surface of asteroids. After the discs cut into the rock surface, the self-locking function of the arms provides forces to fix the lander on the surface. Modeling, trajectory planning, simulations, mechanism design, and prototype fabrication of the anchoring system are discussed, respectively. The performances of the system are tested on different kinds of rocks, at different sawing angles, locations, and speeds. Results show that the system can cut 15 mm deep into granite rock in 180 s at sawing angle of 60°, with the average power of 58.41 W, and the "weight on bit" (WOB) of 8.637 N. The 7.8 kg anchoring system is capable of providing omni-directional anchoring forces, at least 225 N normal and 157 N tangent to the surface of the rock. The system has the advantages of low-weight, low energy consumption and balance forces, high anchoring efficiency and reliability, and could enable the lander to move and sample or assist astronauts and robots in walking and sampling on asteroids.

  7. Anchors as Semantic Primes in Value Construction: An EEG Study of the Anchoring Effect.

    Directory of Open Access Journals (Sweden)

    Qingguo Ma

    Full Text Available Previous research regarding anchoring effects has demonstrated that human judgments are often assimilated to irrelevant information. Studies have demonstrated that anchors influence the economic valuation of various products and experiences; however, the cognitive explanations of this effect remain controversial, and its neural mechanisms have rarely been explored. In the current study, we conducted an electroencephalography (EEG experiment to investigate the anchoring effect on willingness to accept (WTA for an aversive hedonic experience and the role of anchors in this judgment heuristic. The behavioral results demonstrated that random numbers affect participants' WTA for listening to pieces of noise. The participants asked for higher pay after comparing their WTA with higher numbers. The EEG results indicated that anchors also influenced the neural underpinnings of the valuation process. Specifically, when a higher anchor number was drawn, larger P2 and late positive potential amplitudes were elicited, reflecting the anticipation of more intensive pain from the subsequent noise. Moreover, higher anchors induced a stronger theta band power increase compared with lower anchors when subjects listened to the noises, indicating that the participants felt more unpleasant during the actual experience of the noise. The levels of unpleasantness during both anticipation and experience were consistent with the semantic information implied by the anchors. Therefore, these data suggest that a semantic priming process underlies the anchoring effect in WTA. This study provides proof for the robustness of the anchoring effect and neural evidence of the semantic priming model. Our findings indicate that activated contextual information, even seemingly irrelevant, can be embedded in the construction of economic value in the brain.

  8. Susceptibility to anchoring effects

    Directory of Open Access Journals (Sweden)

    Todd McElroy

    2007-02-01

    Full Text Available Previous research on anchoring has shown this heuristic to be a very robust psychological phenomenon ubiquitous across many domains of human judgment and decision-making. Despite the prevalence of anchoring effects, researchers have only recently begun to investigate the underlying factors responsible for how and in what ways a person is susceptible to them. This paper examines how one such factor, the Big-Five personality trait of openness-to-experience, influences the effect of previously presented anchors on participants' judgments. Our findings indicate that participants high in openness-to-experience were significantly more influenced by anchoring cues relative to participants low in this trait. These findings were consistent across two different types of anchoring tasks providing convergent evidence for our hypothesis.

  9. Constrained Active Learning for Anchor Link Prediction Across Multiple Heterogeneous Social Networks.

    Science.gov (United States)

    Zhu, Junxing; Zhang, Jiawei; Wu, Quanyuan; Jia, Yan; Zhou, Bin; Wei, Xiaokai; Yu, Philip S

    2017-08-03

    Nowadays, people are usually involved in multiple heterogeneous social networks simultaneously. Discovering the anchor links between the accounts owned by the same users across different social networks is crucial for many important inter-network applications, e.g., cross-network link transfer and cross-network recommendation. Many different supervised models have been proposed to predict anchor links so far, but they are effective only when the labeled anchor links are abundant. However, in real scenarios, such a requirement can hardly be met and most anchor links are unlabeled, since manually labeling the inter-network anchor links is quite costly and tedious. To overcome such a problem and utilize the numerous unlabeled anchor links in model building, in this paper, we introduce the active learning based anchor link prediction problem. Different from the traditional active learning problems, due to the one-to-one constraint on anchor links, if an unlabeled anchor link a = ( u , v ) is identified as positive (i.e., existing), all the other unlabeled anchor links incident to account u or account v will be negative (i.e., non-existing) automatically. Viewed in such a perspective, asking for the labels of potential positive anchor links in the unlabeled set will be rewarding in the active anchor link prediction problem. Various novel anchor link information gain measures are defined in this paper, based on which several constraint active anchor link prediction methods are introduced. Extensive experiments have been done on real-world social network datasets to compare the performance of these methods with state-of-art anchor link prediction methods. The experimental results show that the proposed Mean-entropy-based Constrained Active Learning (MC) method can outperform other methods with significant advantages.

  10. Comparison of Suture-Based Anchors and Traditional Bioabsorbable Anchors in Foot and Ankle Surgery.

    Science.gov (United States)

    Hembree, W Chad; Tsai, Michael A; Parks, Brent G; Miller, Stuart D

    We compared the pullout strength of a suture-based anchor versus a bioabsorbable anchor in the distal fibula and calcaneus and evaluated the relationship between bone mineral density and peak load to failure. Eight paired cadaveric specimens underwent a modified Broström procedure and Achilles tendon reattachment. The fibula and calcaneus in the paired specimens received either a suture-based anchor or a bioabsorbable suture anchor. The fibular and calcaneal specimens were loaded to failure, defined as a substantial decrease in the applied load or pullout from the bone. In the fibula, the peak load to failure was significantly greater with the suture-based versus the bioabsorbable anchors (133.3 ± 41.8 N versus 76.8 ± 35.3 N; p = .002). No significant difference in load with 5 mm of displacement was found between the 2 groups. In the calcaneus, no difference in the peak load to failure was found between the 2 groups, and the peak load to failure with 5 mm of displacement was significantly lower with the suture-based than with the bioabsorbable anchors (52.2 ± 9.8 N versus 75.9 ± 12.4 N; p = .003). Bone mineral density and peak load to failure were significantly correlated in the fibula with the suture-based anchor. An innovative suture-based anchor had a greater peak load to failure compared with a bioabsorbable anchor in the fibula. In the calcaneus, the load at 5 mm of displacement was significantly lower in the suture-based than in the bioabsorbable group. The correlation findings might indicate the need for a cortical bone shelf with the suture-based anchor. Suture-based anchors could be a viable alternative to bioabsorbable anchors for certain foot and ankle procedures. Copyright © 2016 American College of Foot and Ankle Surgeons. Published by Elsevier Inc. All rights reserved.

  11. Yeast arming systems: pros and cons of different protein anchors and other elements required for display.

    Science.gov (United States)

    Andreu, Cecilia; Del Olmo, Marcel Lí

    2018-03-01

    Yeast display is a powerful strategy that consists in exposing peptides or proteins of interest on the cell surface of this microorganism. Ever since initial experiments with this methodology were carried out, its scope has extended and many applications have been successfully developed in different science and technology fields. Several yeast display systems have been designed, which all involve introducting into yeast cells the gene fusions that contain the coding regions of a signal peptide, an anchor protein, to properly attach the target to the cell surface, and the protein of interest to be exposed, all of which are controlled by a strong promoter. In this work, we report the description of such elements for the alternative systems introduced by focusing particularly on anchor proteins. The comparisons made between them are included whenever possible, and the main advantages and inconveniences of each one are discussed. Despite the huge number of publications on yeast surface display and the revisions published to date, this topic has not yet been widely considered. Finally, given the growing interest in developing systems for non-Saccharomyces yeasts, the main strategies reported for some are also summarized.

  12. ANTS-anchored Zn-Al-CO{sub 3}-LDH particles as fluorescent probe for sensing of folic acid

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Pengfei; Liu, Dan; Liu, Yanhuan [State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing 100029 (China); Beijing Key Laboratory of Environmentally Harmful Chemical Analysis, Beijing University of Chemical Technology, Beijing 100029 (China); Li, Lei, E-mail: lilei@mail.buct.edu.cn [State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing 100029 (China); Beijing Key Laboratory of Environmentally Harmful Chemical Analysis, Beijing University of Chemical Technology, Beijing 100029 (China)

    2016-09-15

    A novel fluorescent nanosensor for detecting folic acid (FA) in aqueous media has been developed based on 8-aminonaphthalene-1,3,6-trisulfonate (ANTS) anchored to the surface of Zn-Al-CO{sub 3}-layered double hydroxides (LDH) particles. The nanosensor showed high fluorescence intensity and good photostability due to a strong coordination interaction between surface Zn{sup 2+} ions of Zn-Al-CO{sub 3}-LDH and N atoms of ANTS, which were verified by result of X-ray photoelectron spectroscopy (XPS). ANTS-anchored on the surface of Zn-Al-CO{sub 3}-LDH restricted the intra-molecular rotation leading to ANTS-anchored J-type aggregation emission enhancement. ANTS-anchored Zn-Al-CO{sub 3}-LDH particles exhibited highly sensitive and selective response to FA over other common metal ions and saccharides present in biological fluids. The proposed mechanism was that oxygen atoms of -SO{sub 3} groups in ANTS-anchored on the surface of Zn-Al-CO{sub 3}-LDH were easily collided by FA molecules to form potential hydrogen bonds between ANTS-anchored and FA molecules, which could effectively quench the ANTS-anchored fluorescence. Under the simulated physiological conditions (pH of 7.4), the fluorescence quenching was fitted to Stern-Volmer equation with a linear response in the concentration range of 1 μM to 200 μM with a limit of detection of 0.1 μM. The results indicate that ANTS-anchored Zn-Al-CO{sub 3}-LDH particles can afford a very sensitive system for the sensing FA in aqueous solution. - Highlights: • A novel fluorescent nanosensor has been developed. • The sensor exhibited highly sensitive and selective response to FA. • The fluorescence quenching was fitted to Stern–Volmer equation. • The linear response range was 1–200 μM with a limit of detection of 0.1 μM.

  13. The cell wall-localized atypical β-1,3 glucanase ZERZAUST controls tissue morphogenesis in Arabidopsis thaliana.

    Science.gov (United States)

    Vaddepalli, Prasad; Fulton, Lynette; Wieland, Jennifer; Wassmer, Katrin; Schaeffer, Milena; Ranf, Stefanie; Schneitz, Kay

    2017-06-15

    Orchestration of cellular behavior in plant organogenesis requires integration of intercellular communication and cell wall dynamics. The underlying signaling mechanisms are poorly understood. Tissue morphogenesis in Arabidopsis depends on the receptor-like kinase STRUBBELIG. Mutations in ZERZAUST were previously shown to result in a strubbelig -like mutant phenotype. Here, we report on the molecular identification and functional characterization of ZERZAUST We show that ZERZAUST encodes a putative GPI-anchored β-1,3 glucanase suggested to degrade the cell wall polymer callose. However, a combination of in vitro , cell biological and genetic experiments indicate that ZERZAUST is not involved in the regulation of callose accumulation. Nonetheless, Fourier-transformed infrared-spectroscopy revealed that zerzaust mutants show defects in cell wall composition. Furthermore, the results indicate that ZERZAUST represents a mobile apoplastic protein, and that its carbohydrate-binding module family 43 domain is required for proper subcellular localization and function whereas its GPI anchor is dispensable. Our collective data reveal that the atypical β-1,3 glucanase ZERZAUST acts in a non-cell-autonomous manner and is required for cell wall organization during tissue morphogenesis. © 2017. Published by The Company of Biologists Ltd.

  14. Reinforcing mechanism of anchors in slopes: a numerical comparison of results of LEM and FEM

    Science.gov (United States)

    Cai, Fei; Ugai, Keizo

    2003-06-01

    This paper reports the limitation of the conventional Bishop's simplified method to calculate the safety factor of slopes stabilized with anchors, and proposes a new approach to considering the reinforcing effect of anchors on the safety factor. The reinforcing effect of anchors can be explained using an additional shearing resistance on the slip surface. A three-dimensional shear strength reduction finite element method (SSRFEM), where soil-anchor interactions were simulated by three-dimensional zero-thickness elasto-plastic interface elements, was used to calculate the safety factor of slopes stabilized with anchors to verify the reinforcing mechanism of anchors. The results of SSRFEM were compared with those of the conventional and proposed approaches for Bishop's simplified method for various orientations, positions, and spacings of anchors, and shear strengths of soil-grouted body interfaces. For the safety factor, the proposed approach compared better with SSRFEM than the conventional approach. The additional shearing resistance can explain the influence of the orientation, position, and spacing of anchors, and the shear strength of soil-grouted body interfaces on the safety factor of slopes stabilized with anchors.

  15. Unlocking Hospitality Managers Career Transitions through Applying Schein's Career Anchors Theory

    Science.gov (United States)

    McGuire, David; Polla, Giovana; Heidl, Britta

    2017-01-01

    Purpose: This paper seeks to unlock the career transitions of hospitality managers through applying Schein's career anchors theory. It seeks to understand how Schein's Career Anchors help explain the career transitions of managers in the Scottish hospitality industry. Design/methodology/approach: The paper adopts a non-sequential multi-method…

  16. JOB SATISFACTION AND CAREER CHOICES: A STUDY USING SCHEIN´S CAREER ANCHOR MODEL

    OpenAIRE

    Codaro, Rosana Silvina; Tomei, Patricia Amelia; Serra, Bernardo Paraiso de Campos

    2017-01-01

    This study explores the relationship between job satisfaction and alignment between the individual´s current occupation and his/her talents, needs and values, namely as career anchors. A quantitative survey using Schein e Van Maanen´s Career Anchor model (2013) and Siqueira´s Job Satisfaction survey (2008) was performed for a non-probabilistic sample students at the Business School of a private University in Rio de Janeiro. The most frequent career anchor found for both genders was Lifestyle,...

  17. Complex Spiral Structure in the HD 100546 Transitional Disk as Revealed by GPI and MagAO

    Energy Technology Data Exchange (ETDEWEB)

    Follette, Katherine B.; Macintosh, Bruce; Mullen, Wyatt; Bailey, Vanessa P. [Kavli Institute for Particle Astrophysics and Cosmology, Department of Physics, Stanford University, Stanford, CA, 94305 (United States); Rameau, Julien [Institut de Recherche sur les Exoplanètes, Départment de Physique, Université de Montréal, Montréal QC H3C 3J7 (Canada); Dong, Ruobing; Close, Laird M.; Males, Jared R.; Morzinski, Katie M. [Steward Observatory, University of Arizona, Tucson, AZ 85721 (United States); Pueyo, Laurent; Perrin, Marshall [Space Telescope Science Institute, Baltimore, MD 21218 (United States); Duchêne, Gaspard; Fung, Jeffrey; Wang, Jason [Astronomy Department, University of California, Berkeley, Berkeley CA 94720 (United States); Leonard, Clare; Spiro, Elijah [Physics and Astronomy Department, Amherst College, 21 Merrill Science Drive, Amherst, MA 01002 (United States); Marois, Christian [National Research Council of Canada Herzberg, 5071 West Saanich Road, Victoria, BC V9E 2E7 (Canada); Millar-Blanchaer, Maxwell A. [Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91125 (United States); Ammons, S. Mark [Lawrence Livermore National Laboratory, Livermore, CA 94551 (United States); Barman, Travis [Lunar and Planetary Laboratory, University of Arizona, Tucson, AZ 85721 (United States); and others

    2017-06-01

    We present optical and near-infrared high-contrast images of the transitional disk HD 100546 taken with the Magellan Adaptive Optics system (MagAO) and the Gemini Planet Imager (GPI). GPI data include both polarized intensity and total intensity imagery, and MagAO data are taken in Simultaneous Differential Imaging mode at H α . The new GPI H -band total intensity data represent a significant enhancement in sensitivity and field rotation compared to previous data sets and enable a detailed exploration of substructure in the disk. The data are processed with a variety of differential imaging techniques (polarized, angular, reference, and simultaneous differential imaging) in an attempt to identify the disk structures that are most consistent across wavelengths, processing techniques, and algorithmic parameters. The inner disk cavity at 15 au is clearly resolved in multiple data sets, as are a variety of spiral features. While the cavity and spiral structures are identified at levels significantly distinct from the neighboring regions of the disk under several algorithms and with a range of algorithmic parameters, emission at the location of HD 100546 “ c ” varies from point-like under aggressive algorithmic parameters to a smooth continuous structure with conservative parameters, and is consistent with disk emission. Features identified in the HD 100546 disk bear qualitative similarity to computational models of a moderately inclined two-armed spiral disk, where projection effects and wrapping of the spiral arms around the star result in a number of truncated spiral features in forward-modeled images.

  18. Composite materials formed with anchored nanostructures

    Science.gov (United States)

    Seals, Roland D; Menchhofer, Paul A; Howe, Jane Y; Wang, Wei

    2015-03-10

    A method of forming nano-structure composite materials that have a binder material and a nanostructure fiber material is described. A precursor material may be formed using a mixture of at least one metal powder and anchored nanostructure materials. The metal powder mixture may be (a) Ni powder and (b) NiAl powder. The anchored nanostructure materials may comprise (i) NiAl powder as a support material and (ii) carbon nanotubes attached to nanoparticles adjacent to a surface of the support material. The process of forming nano-structure composite materials typically involves sintering the mixture under vacuum in a die. When Ni and NiAl are used in the metal powder mixture Ni.sub.3Al may form as the binder material after sintering. The mixture is sintered until it consolidates to form the nano-structure composite material.

  19. Experimental Research on Destruction Mode and Anchoring Performance of Carbon Fiber Phyllostachys pubescens Anchor Rod with Different Forms

    Directory of Open Access Journals (Sweden)

    Wang Yulan

    2018-01-01

    Full Text Available The anchoring technology is extensively applied in reinforcing protection of the earth relics. Now that no specification is available for different new anchor rods in earth relics protection due to diversified destruction modes of earth relics and complexity of engineering technology conditions, it is urgent to guide reinforcing design and construction with a complete detailed anchor rod research document. With the new carbon fiber Phyllostachys pubescens anchor rod as the research object, six lots of in situ tests are designed to, respectively, study the destruction mode and anchoring performance of the carbon fiber Phyllostachys pubescens anchor rod under different anchor length L, anchor rod diameter D, bore diameter H, grouting material S, rib spacing R, and inclination angle A in this paper. By studying load shift curve experiment in drawing of the anchor rod, the destruction mode and ultimate bearing capacity of the carbon fiber Phyllostachys pubescens anchor rod in different experiment lots are obtained, and the concept of permitted application value N in anchor rod design is proposed. By studying strain distribution characteristics of anchor rods in experimental lots along the length direction under action of the permitted application value N and combining the existing destruction mode and ultimate bearing capacity, this paper analyzes influences of L, D, H, S, R, and A on anchoring effect of the carbon fiber Phyllostachys pubescens anchor rod; gives the reasonable value range of L, D, H, and R when the carbon fiber Phyllostachys pubescens anchor rod is used for reinforcing design of the earth relics; and provides favorable experiment basis for reinforcing design of the earth relics based on the carbon fiber Phyllostachys pubescens anchor rod.

  20. Treatment response in Kawasaki disease is associated with sialylation levels of endogenous but not therapeutic intravenous immunoglobulin G.

    Directory of Open Access Journals (Sweden)

    Shohei Ogata

    Full Text Available Although intravenous immunoglobulin (IVIG is highly effective in Kawasaki disease (KD, mechanisms are not understood and 10-20% of patients are treatment-resistant, manifesting a higher rate of coronary artery aneurysms. Murine models suggest that α2-6-linked sialic acid (α2-6Sia content of IVIG is critical for suppressing inflammation. However, pro-inflammatory states also up-regulate endogenous levels of β-galactoside:α2-6 sialyltransferase-I (ST6Gal-I, the enzyme that catalyzes addition of α2-6Sias to N-glycans. We asked whether IVIG failures correlated with levels of α2-6Sia on infused IVIG or on the patient's own endogenous IgG.We quantified levels of α2-6Sia in infused IVIG and endogenous IgG from 10 IVIG-responsive and 10 resistant KD subjects using multiple approaches. Transcript levels of ST6GAL1, in patient whole blood and B cell lines were evaluated by RT-PCR. Plasma soluble (sST6Gal-I levels were measured by ELISA.There was no consistent difference in median sialylation levels of infused IVIG between groups. However, α2-6Sia levels in endogenous IgG, ST6GAL1 transcript levels, and ST6Gal-I protein in serum from IVIG-resistant KD subjects were lower than in responsive subjects at both pre-treatment and one-year time points (p <0.001, respectively.Our data indicate sialylation levels of therapeutic IVIG are unrelated to treatment response in KD. Rather, lower sialylation of endogenous IgG and lower blood levels of ST6GALI mRNA and ST6Gal-I enzyme predict therapy resistance. These differences were stable over time, suggesting a genetic basis. Because IVIG-resistance increases risk of coronary artery aneurysms, our findings have important implications for the identification and treatment of such individuals.

  1. Interaction of hamster submaxillary sialyl-Tn and Tn glycoproteins with Gal, GalNAc and GlcNAc specific lectins.

    Science.gov (United States)

    Wu, A M; Shen, F; Herp, A; Wu, J H

    1994-04-01

    Hamster submaxillary glycoprotein (HSM), one of the simplest glycoproteins among mammalian salivary mucins, is composed of approximately equivalent amounts of protein, hexosamine and sialic acid. The Thr and Ser residues in the protein core account for more than half of all of the amino acid residues, while Lys, Glu, Pro and Ala are the major components of the remaining portion of amino acids. The carbohydrate side chains of this mucous glycoprotein have mainly the NeuAc-GalNAc-(sialyl-Tn) sequence (HSM), and those of the desialylated product (HSM-Tn) are almost exclusively unsubstituted GalNAc residues (Tn determinants). The binding properties of sialyl-Tn (HSM) and asialo-HSM (HSM-Tn) glycoproteins were tested by precipitin assay with Gal, GalNAc and GlcNAc specific lectins. The HSM-Tn completely precipitated Vicia villosa (VVL both B4 and mixture of A and B), Maclura pomifera (MPL), and Artocarpus integrifolia (Jacalin) lectins; less than 2 micrograms of HSM-Tn were required for precipitating 50% of 5.0-6.3 micrograms lectin nitrogen added. HSM-Tn also reacted well with Helix pomatia lectin (HPL), Wistaria floribunda lectin (WFL) and Abrus precatorius agglutinin (APA) and precipitated in each case over 81% of the lectin nitrogen added. The reactivity of HSM-Tn with other lectins (Ricinus communis, RCA1; Dolichol biflorus, DBL; Viscum album, ML-I; Arachis hypogaea, PNA, and Triticum vulgaris, WGA) was weak or negligible. The activity of sialyl-Tn (HSM) was more restricted; HSM reacted well with Jacalin, moderately with MPL and VVL-B4, but was inactive or only weakly with the other lectins used. These findings indicate that HSM and its desialylated product (HSM-Tn) are highly useful reagents for the differentiation of Tn and T/Gal specific lectins and for anti-T, Tn and Af monoclonal antibodies.

  2. Experimental testing of anchoring devices for bottom rails in partially anchored timber frame shear walls

    OpenAIRE

    Caprolu, Giuseppe

    2011-01-01

    Källsner and Girhammar have presented a new plastic design method of wood-framed shear walls at ultimate limit state. This method allows the designer to calculate the load-carrying capacity of shear walls partially anchored, where the leading stud is not anchored against the uplift.The anchorage system of shear walls is provided from anchor bolts and hold downs. Anchor bolts provide horizontal shear continuity between the bottom rail and the foundation. Hold downs are directly connected from ...

  3. Endocytosis of GPI-linked membrane folate receptor-alpha.

    Science.gov (United States)

    Rijnboutt, S; Jansen, G; Posthuma, G; Hynes, J B; Schornagel, J H; Strous, G J

    1996-01-01

    GPI-linked membrane folate receptors (MFRs) have been implicated in the receptor-mediated uptake of reduced folate cofactors and folate-based chemotherapeutic drugs. We have studied the biosynthetic transport to and internalization of MFR isoform alpha in KB-cells. MFR-alpha was synthesized as a 32-kD protein and converted in a maturely glycosylated 36-38-kD protein 1 h after synthesis. 32-kD MFR-alpha was completely soluble in Triton X-100 at 0 degree C. In contrast, only 33% of the 36-38-kD species could be solubilized at these conditions whereas complete solubilization was obtained in Triton X-100 at 37 degrees C or in the presence of saponin at 0 degree C. Similar solubilization characteristics were found when MFR-alpha at the plasma membrane was labeled with a crosslinkable 125I-labeled photoaffinity-analog of folic acid as a ligand. Triton X-100-insoluble membrane domains containing MFR-alpha could be separated from soluble MFR-alpha on sucrose flotation gradients. Only Triton X-100 soluble MFR-alpha was internalized from the plasma membrane. The reduced-folate-carrier, an integral membrane protein capable of translocating (anti-)folates across membranes, was completely excluded from the Triton X-100-resistant membrane domains. Internalized MFR-alpha recycled slowly to the cell surface during which it remained soluble in Triton X-100 at 0 degree C. Using immunoelectron microscopy, we found MFR-alpha along the entire endocytic pathway: in clathrin-coated buds and vesicles, and in small and large endosomal vacuoles. In conclusion, our data indicate that a large fraction, if not all, of internalizing MFR-alpha bypasses caveolae.

  4. Journal of Biosciences | Indian Academy of Sciences

    Indian Academy of Sciences (India)

    2011-07-08

    specific phospholipase C (PI-PLC), and the subsequent recognition by antibodies specific for the cross-reacting determinant (CRD), revealed that HBP is glycosylphosphatidylinositol (GPI)-anchored protein and, further, that the ...

  5. Traction endurance biomechanical study of metallic suture anchors at different insertion angles

    Directory of Open Access Journals (Sweden)

    Azato Flávia Namie

    2003-01-01

    Full Text Available The suture anchors' insertion angle and its traction resistance are the main subjects of this study. Twenty trials were realized using threaded suture anchors in four diferents angulations (30º /45º /60º /90º in human bone (distal femur and another twenty trials in artificial bone (SawboneTM. The anchors were pulled out being tractioned uprightly from its bone surface by a Kratos Universal test machine. The human bone results found no relation between the main subjects of this study, so whithout statistical value. On the other hand at the artificial bone the insertion angle of 90º beared more traction, being statistically significant compared to the other angles.

  6. Intermittent use of an "anchor system" improves postural control in healthy older adults.

    Science.gov (United States)

    Freitas, Milena de Bem Zavanella; Mauerberg-deCastro, Eliane; Moraes, Renato

    2013-07-01

    Haptic information, provided by a non-rigid tool (i.e., an "anchor system"), can reduce body sway in individuals who perform a standing postural task. However, it was not known whether or not continuous use of the anchor system would improve postural control after its removal. Additionally, it was unclear as to whether or not frequency of use of the anchor system is related to improved control in older adults. The present study evaluated the effect of the prolonged use of the anchor system on postural control in healthy older individuals, at different frequencies of use, while they performed a postural control task (semi-tandem position). Participants were divided into three groups according to the frequency of the anchor system's use (0%, 50%, and 100%). Pre-practice phase (without anchor) was followed by a practice phase (they used the anchor system at the predefined frequency), and a post-practice phase (immediate and late-without anchor). All three groups showed a persistent effect 15min after the end of the practice phase (immediate post-practice phase). However, only the 50% group showed a persistent effect in the late post-practice phase (24h after finishing the practice phase). Older adults can improve their postural control by practicing the standing postural task, and use of the anchor system limited to half of their practice time can provide additional improvement in their postural control. Copyright © 2013 Elsevier B.V. All rights reserved.

  7. Investigation of the effect of heated ethanol fuel on combustion and emissions of an ethanol direct injection plus gasoline port injection (EDI + GPI) engine

    International Nuclear Information System (INIS)

    Huang, Yuhan; Hong, Guang

    2016-01-01

    Highlights: • Effect of EDI heating on the EDI + GPI engine performance was investigated. • CO and HC were significantly reduced and NO was slightly increased by EDI heating. • IMEP and combustion speed were slightly reduced by EDI heating. • EDI heating is effective to address the evaporation and over-cooling issues of EDI + GPI engine. - Abstract: Ethanol direct injection plus gasoline port injection (EDI + GPI) is a new technology to utilise ethanol fuel more efficiently and flexibly in spark ignition engines. One issue needs to be addressed in the development of EDI + GPI is the ethanol fuel’s low vapour pressure and large latent heat which slow down the ethanol’s evaporation and result in the mixture unready for combustion by the time of spark ignition and the consequent increase of CO and HC emissions. Heating the ethanol fuel to be directly injected (EDI heating) has been proposed to address this issue. This paper reports the investigation of the effect of EDI heating on the combustion and emissions of a research engine equipped with EDI + GPI. The results showed that EDI heating effectively reduced the CO and HC emissions of the engine due to the increase of evaporation rate and reduced fuel impingement and local over-cooling. The reduction of CO and HC became more significant with the increase of ethanol ratio. When the temperature of the ethanol fuel was increased by 40 °C, the CO and HC were reduced by as much as 43% and 51% respectively in EDI only condition at the original spark timing of 15 CAD BTDC, and 15% and 47% respectively at the minimum spark advance for best torque (MBT) timing of 19 CAD BTDC. On the other hand, the NO emission was slightly increased, but still much smaller than that in GPI only condition due to the strong cooling effect and low combustion temperature of EDI. The IMEP and combustion speed were slightly reduced by EDI heating due to the decrease of injector fuel flow rate and spray collapse of flash-boiling. The

  8. Side-by-side comparison of Raman spectra of anchored and suspended carbon nanomaterials

    International Nuclear Information System (INIS)

    Sidorov, Anton N; Pabba, Santosh; Cohn, Robert W; Sumanasekera, G U; Hewaparakrama, Kapila P

    2008-01-01

    Raman spectra of ordered carbon nanomaterials are quite sensitive to surface perturbations, including trace residues, structural defects and residual stress. This is demonstrated by a series of experiments with carbon nanotubes and graphene. Their spectra change due to subtle changes in preparation and attachment to the substrate and to each other. Differences are most clearly seen by forming a material into an air bridge and probing it in the air gap and at the anchor points. A monolayer graphene sheet, shows a larger disorder band at the anchor points than in the air gap. However, a bundle or rope of parallel-aligned single-wall nanotubes shows a larger disorder band in the gap than at the anchor points. For the graphene sheet the substrate surface deforms the graphene, leading to increases in the disorder band. For the rope, the close proximity of the nanotubes to each other appears to produce a larger stress than the rope resting on the substrate

  9. Not all Anchors Weigh Equally.

    Science.gov (United States)

    Greenstein, Michael; Velazquez, Alexandra

    2017-11-01

    The anchoring bias is a reliable effect wherein a person's judgments are affected by initially presented information, but it is unknown specifically why this effect occurs. Research examining this bias suggests that elements of both numeric and semantic priming may be involved. To examine this, the present research used a phenomenon wherein people treat numeric information presented differently in Arabic numeral or verbal formats. We presented participants with one of many forms of an anchor that represented the same value (e.g., twelve hundred or 1,200). Thus, we could examine how a concept's meaning and its absolute numeric value affect anchoring. Experiments 1 and 2 showed that people respond to Arabic and verbal anchors differently. Experiment 3 showed that these differences occurred largely because people tend to think of numbers in digit format. This suggests that one's conceptual understanding of the anchored information matters more than its strict numeric value.

  10. Investigation into the behaviour of concrete anchored diaphragm walls under earthquake condition

    International Nuclear Information System (INIS)

    Saba, H. R.; Rahaii, A. R.

    2003-01-01

    Diaphragm walls are frequently used in civil Engineering projects. Considering the variety and important volume of consumed materials (concrete, anchors and soil), one of the important factors for design and construction of these walls, are their behaviour under different executive, and loading conditions. In this paper, various models of concrete diaphragms with different number of anchors and soil parameters under static and dynamic loading have been investigated using finite element method with nonlinear models. Results including the internal forces in diaphragm walls, variation of forces in the anchors, shape of the sliding surface and variation of pressure in soil are obtained and compared. An experimental tool with suitable measurement systems for determining the pressure and internal forces was designed and realised. Also with similitude and dimensional analyses, diaphragms with different number of anchors were built and set on the shaking table test and experimented under different accelograms. Finally results of nonlinear dynamic analysis were compared with experimental results

  11. Dependence of optical phase modulation on anchoring strength of dielectric shield wall surfaces in small liquid crystal pixels

    Science.gov (United States)

    Isomae, Yoshitomo; Shibata, Yosei; Ishinabe, Takahiro; Fujikake, Hideo

    2018-03-01

    We demonstrated that the uniform phase modulation in a pixel can be realized by optimizing the anchoring strength on the walls and the wall width in the dielectric shield wall structure, which is the needed pixel structure for realizing a 1-µm-pitch optical phase modulator. The anchoring force degrades the uniformity of the phase modulation in ON-state pixels, but it also keeps liquid crystals from rotating against the leakage of an electric field. We clarified that the optimal wall width and anchoring strength are 250 nm and less than 10-4 J/m2, respectively.

  12. Self-interacting polymer chains terminally anchored to adsorbing surfaces of three-dimensional fractal lattices

    Science.gov (United States)

    Živić, I.; Elezović-Hadžić, S.; Milošević, S.

    2018-01-01

    We have studied the adsorption problem of self-attracting linear polymers, modeled by self-avoiding walks (SAWs), situated on three-dimensional fractal structures, exemplified by 3d Sierpinski gasket (SG) family of fractals as containers of a poor solvent. Members of SG family are enumerated by an integer b (b ≥ 2), and it is assumed that one side of each SG fractal is an impenetrable adsorbing surface. We calculate the critical exponents γ1 ,γ11, and γs, which are related to the numbers of all possible SAWs with one, both, and no ends anchored to the adsorbing boundary, respectively. By applying the exact renormalization group (RG) method (for the first three members of the SG fractal family, b = 2 , 3, and 4), we have obtained specific values of these exponents, for θ-chain and globular polymer phase. We discuss their mutual relations and relations with corresponding values pertinent to extended polymer chain phase.

  13. Different size biomolecules anchoring on porous silicon surface: fluorescence and reflectivity pores infiltration comparative studies

    Energy Technology Data Exchange (ETDEWEB)

    Giovannozzi, Andrea M.; Rossi, Andrea M. [National Institute for Metrological Research, Thermodynamic Division, Strada delle Cacce 91, 10135 Torino (Italy); Renacco, Chiara; Farano, Alessandro [Ribes Ricecrhe Srl, Via Lavoratori Vittime del Col du Mont 24, 11100 Aosta (Italy); Derosas, Manuela [Biodiversity Srl, Via Corfu 71, 25124 Brescia (Italy); Enrico, Emanuele [National Institute for Metrological Research, Electromagnetism Division, Strada delle Cacce 91, 10135 Torino (Italy)

    2011-06-15

    The performance of porous silicon optical based biosensors strongly depends on material nanomorphology, on biomolecules distribution inside the pores and on the ability to link sensing species to the pore walls. In this paper we studied the immobilization of biomolecules with different size, such as antibody anti aflatoxin (anti Aflatox Ab, {proportional_to}150 KDa), malate dehydrogenase (MDH, {proportional_to}36KDa) and metallothionein (MT, {proportional_to}6KDa) at different concentrations on mesoporous silicon samples ({proportional_to}15 nm pores diameter). Fluorescence measurements using FITC- labeled biomolecules and refractive index analysis based on reflectivity spectra have been employed together to detect the amount of proteins bound to the surface and to evaluate their diffusion inside the pores. Here we suggest that these two techniques should be used together to have a better understanding of what happens at the porous silicon surface. In fact, when pores dimensions are not perfectly tuned to the protein size a higher fluorescence signal doesn't often correspond to a higher biomolecules distribution inside the pores. When a too much higher concentration of biomolecule is anchored on the surface, steric crowd effects and repulsive interactions probably take over and hinder pores infiltration, inducing a small or absent shift in the fringe pattern even if a higher fluorescence signal is registered. (copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  14. High-resolution structure of TBP with TAF1 reveals anchoring patterns in transcriptional regulation.

    Science.gov (United States)

    Anandapadamanaban, Madhanagopal; Andresen, Cecilia; Helander, Sara; Ohyama, Yoshifumi; Siponen, Marina I; Lundström, Patrik; Kokubo, Tetsuro; Ikura, Mitsuhiko; Moche, Martin; Sunnerhagen, Maria

    2013-08-01

    The general transcription factor TFIID provides a regulatory platform for transcription initiation. Here we present the crystal structure (1.97 Å) and NMR analysis of yeast TAF1 N-terminal domains TAND1 and TAND2 bound to yeast TBP, together with mutational data. We find that yeast TAF1-TAND1, which in itself acts as a transcriptional activator, binds TBP's concave DNA-binding surface by presenting similar anchor residues to TBP as does Mot1 but from a distinct structural scaffold. Furthermore, we show how TAF1-TAND2 uses an aromatic and acidic anchoring pattern to bind a conserved TBP surface groove traversing the basic helix region, and we find highly similar TBP-binding motifs also presented by the structurally distinct TFIIA, Mot1 and Brf1 proteins. Our identification of these anchoring patterns, which can be easily disrupted or enhanced, provides insight into the competitive multiprotein TBP interplay critical to transcriptional regulation.

  15. Liquifying PLDLLA Anchor Fixation in Achilles Reconstruction for Insertional Tendinopathy.

    Science.gov (United States)

    Boden, Stephanie A; Boden, Allison L; Mignemi, Danielle; Bariteau, Jason T

    2018-04-01

    Insertional Achilles tendinopathy (IAT) is a frequent cause of posterior heel pain and is often associated with Haglund's deformity. Surgical correction for refractory cases of IAT has been well studied; however, the method of tendon fixation to bone in these procedures remains controversial, and to date, no standard technique has been identified for tendon fixation in these surgeries. Often, after Haglund's resection, there is large exposed cancellous surface for Achilles reattachment, which may require unique fixation to optimize outcomes. Previous studies have consistently demonstrated improved patient outcomes after Achilles tendon reconstruction with early rehabilitation with protected weight bearing, evidencing the need for a strong and stable anchoring of the Achilles tendon that allows early weight bearing without tendon morbidity. In this report, we highlight the design, biomechanics, and surgical technique of Achilles tendon reconstruction with Haglund's deformity using a novel technique that utilizes ultrasonic energy to liquefy the suture anchor, allowing it to incorporate into surrounding bone. Biomechanical studies have demonstrated superior strength of the suture anchor utilizing this novel technique as compared with prior techniques. However, future research is needed to ensure that outcomes of this technique are favorable when compared with outcomes using traditional suture anchoring methods. Level V: Operative technique.

  16. The relation between career anchors, occupational types and job satisfaction of midcareer employees

    OpenAIRE

    J. A. Ellison; A. M. G. Schreuder

    2000-01-01

    The objective of this research was to determine the value of the career anchor model in career decision-making. Career models that can provide the individual with greater self-insight can serve as an important guide when making career choices in todays turbulent working environment. Two hundred and ninety-five midcareer employees (managerial and non-managerial) completed questionnaires to determine their career anchor, occupation type and levels of general, intrinsic and extrinsic job satisfa...

  17. Enhancement of the Immunogenicity and Protective Efficacy of a Mucosal Influenza Subunit Vaccine by the Saponin Adjuvant GPI-0100

    NARCIS (Netherlands)

    Liu, Heng; Patil, Harshad P.; de Vries-Idema, Jacqueline; Wilschut, Jan; Huckriede, Anke

    2012-01-01

    Identification of safe and effective adjuvants remains an urgent need for the development of inactivated influenza vaccines for mucosal administration. Here, we used a murine challenge model to evaluate the adjuvant activity of GPI-0100, a saponin-derived adjuvant, on influenza subunit vaccine

  18. Cell wall structure suitable for surface display of proteins in Saccharomyces cerevisiae.

    Science.gov (United States)

    Matsuoka, Hiroyuki; Hashimoto, Kazuya; Saijo, Aki; Takada, Yuki; Kondo, Akihiko; Ueda, Mitsuyoshi; Ooshima, Hiroshi; Tachibana, Taro; Azuma, Masayuki

    2014-02-01

    A display system for adding new protein functions to the cell surfaces of microorganisms has been developed, and applications of the system to various fields have been proposed. With the aim of constructing a cell surface environment suitable for protein display in Saccharomyces cerevisiae, the cell surface structures of cell wall mutants were investigated. Four cell wall mutant strains were selected by analyses using a GFP display system via a GPI anchor. β-Glucosidase and endoglucanase II were displayed on the cell surface in the four mutants, and their activities were evaluated. mnn2 deletion strain exhibited the highest activity for both the enzymes. In particular, endoglucanase II activity using carboxymethylcellulose as a substrate in the mutant strain was 1.9-fold higher than that of the wild-type strain. In addition, the activity of endoglucanase II released from the mnn2 deletion strain by Zymolyase 20T treatment was higher than that from the wild-type strain. The results of green fluorescent protein (GFP) and endoglucanase displays suggest that the amounts of enzyme displayed on the cell surface were increased by the mnn2 deletion. The enzyme activity of the mnn2 deletion strain was compared with that of the wild-type strain. The relative value (mnn2 deletion mutant/wild-type strain) of endoglucanase II activity using carboxymethylcellulose as a substrate was higher than that of β-glucosidase activity using p-nitrophenyl-β-glucopyranoside as a substrate, suggesting that the cell surface environment of the mnn2 deletion strain facilitates the binding of high-molecular-weight substrates to the active sites of the displayed enzymes. Copyright © 2014 John Wiley & Sons, Ltd.

  19. Surface antigens and potential virulence factors from parasites detected by comparative genomics of perfect amino acid repeats

    Directory of Open Access Journals (Sweden)

    Adler Joël

    2007-12-01

    Full Text Available Abstract Background Many parasitic organisms, eukaryotes as well as bacteria, possess surface antigens with amino acid repeats. Making up the interface between host and pathogen such repetitive proteins may be virulence factors involved in immune evasion or cytoadherence. They find immunological applications in serodiagnostics and vaccine development. Here we use proteins which contain perfect repeats as a basis for comparative genomics between parasitic and free-living organisms. Results We have developed Reptile http://reptile.unibe.ch, a program for proteome-wide probabilistic description of perfect repeats in proteins. Parasite proteomes exhibited a large variance regarding the proportion of repeat-containing proteins. Interestingly, there was a good correlation between the percentage of highly repetitive proteins and mean protein length in parasite proteomes, but not at all in the proteomes of free-living eukaryotes. Reptile combined with programs for the prediction of transmembrane domains and GPI-anchoring resulted in an effective tool for in silico identification of potential surface antigens and virulence factors from parasites. Conclusion Systemic surveys for perfect amino acid repeats allowed basic comparisons between free-living and parasitic organisms that were directly applicable to predict proteins of serological and parasitological importance. An on-line tool is available at http://genomics.unibe.ch/dora.

  20. A Panel of Recombinant Mucins Carrying a Repertoire of Sialylated O-Glycans Based on Different Core Chains for Studies of Glycan Binding Proteins

    Directory of Open Access Journals (Sweden)

    Reeja Maria Cherian

    2015-08-01

    Full Text Available Sialylated glycans serve as key elements of receptors for many viruses, bacteria, and bacterial toxins. The microbial recognition and their binding specificity can be affected by the linkage of the terminal sugar residue, types of underlying sugar chains, and the nature of the entire glycoconjugate. Owing to the pathobiological significance of sialylated glycans, we have engineered Chinese hamster ovary (CHO cells to secrete mucin-type immunoglobulin-fused proteins carrying terminal α2,3- or α2,6-linked sialic acid on defined O-glycan core saccharide chains. Besides stably expressing P-selectin glycoprotein ligand-1/mouse immunoglobulin G2b cDNA (PSGL-1/mIgG2b, CHO cells were stably transfected with plasmids encoding glycosyltransferases to synthesize core 2 (GCNT1, core 3 (B3GNT6, core 4 (GCNT1 and B3GNT6, or extended core 1 (B3GNT3 chains with or without the type 1 chain-encoding enzyme B3GALT5 and ST6GAL1. Western blot and liquid chromatography-mass spectrometry analysis confirmed the presence of core 1, 2, 3, 4, and extended core 1 chains carrying either type 1 (Galb3GlcNAc or type 2 (Galb4GlcNAc outer chains with or without α2,6-linked sialic acids. This panel of recombinant mucins carrying a repertoire of sialylated O-glycans will be important tools in studies aiming at determining the fine O-glycan binding specificity of sialic acid-specific microbial adhesins and mammalian lectins.

  1. Two new FUT2 (fucosyltransferase 2 gene) missense polymorphisms, 739G→A and 839T→C, are partly responsible for non-secretor status in a Caucasian population from Northern Portugal

    Science.gov (United States)

    2004-01-01

    Secretor status is defined by the expression of H type 1 antigen on gastric surface epithelium and external secretions. The H type 1 structure, and other fucosylated carbohydrates (Lea, sialyl-Lea, Leb, Lex, sialyl-Lex and Ley), can serve as ligands for several pathogens, including Helicobacter pylori, and are cancer-associated antigens. Secretor individuals are more susceptible to some bacterial and viral infections of the genito-urinary and digestive tracts. The aim of the present study was to examine FUT2 (fucosyltransferase 2 gene) polymorphisms in a Caucasian population of non-secretor individuals (n=36) from northern Portugal and to evaluate the activity of the mutant FUT2 enzymes. The secretor status was determined by UEAI [Ulex europaeus (gorse) lectin] histochemistry in gastric mucosa, and FUT2 polymorphisms were studied by restriction-fragment-length polymorphism and direct sequencing. The majority of non-secretors (88.9%) were homozygous for 428G→A polymorphism; 5.6% were homozygous for 571C→T and 5.6% were homozygous for two new missense polymorphisms, 739G→A (2.8%) and 839T→C (2.8%). By kinetic studies it was demonstrated that the two new FUT2 mutants (739G→A and 839T→C) are almost inactive and are responsible for some non-secretor cases. PMID:15250822

  2. Generation of a monoclonal antibody against the glycosylphosphatidylinositol-linked protein Rae-1 using genetically engineered tumor cells.

    Science.gov (United States)

    Hu, Jiemiao; Vien, Long T; Xia, Xueqing; Bover, Laura; Li, Shulin

    2014-02-04

    Although genetically engineered cells have been used to generate monoclonal antibodies (mAbs) against numerous proteins, no study has used them to generate mAbs against glycosylphosphatidylinositol (GPI)-anchored proteins. The GPI-linked protein Rae-1, an NKG2D ligand member, is responsible for interacting with immune surveillance cells. However, very few high-quality mAbs against Rae-1 are available for use in multiple analyses, including Western blotting, immunohistochemistry, and flow cytometry. The lack of high-quality mAbs limits the in-depth analysis of Rae-1 fate, such as shedding and internalization, in murine models. Moreover, currently available screening approaches for identifying high-quality mAbs are excessively time-consuming and costly. We used Rae-1-overexpressing CT26 tumor cells to generate 60 hybridomas that secreted mAbs against Rae-1. We also developed a streamlined screening strategy for selecting the best anti-Rae-1 mAb for use in flow cytometry assay, enzyme-linked immunosorbent assay, Western blotting, and immunostaining. Our cell line-based immunization approach can yield mAbs against GPI-anchored proteins, and our streamlined screening strategy can be used to select the ideal hybridoma for producing such mAbs.

  3. Biomechanical comparison of traditional anchors to all-suture anchors in a double-row rotator cuff repair cadaver model.

    Science.gov (United States)

    Goschka, Andrew M; Hafer, Jason S; Reynolds, Kirk A; Aberle, Nicholas S; Baldini, Todd H; Hawkins, Monica J; McCarty, Eric C

    2015-10-01

    To further reduce the invasiveness of arthroscopic rotator cuff repair surgery the all-suture anchor has been developed. The all-suture anchor requires less bone removal and reduces the potential of loose body complications. The all-suture anchor must also have adequate biomechanical strength for the repair to heal. The hypothesis is there is no significant difference in the biomechanical performance of supraspinatus repairs using an all-suture anchor when compared to traditional solid-body suture anchors. Using nine shoulders per group, the supraspinatus tendon was dissected from the greater tuberosity. The four different double row repairs tested were (medial row/lateral row): A: ICONIX2/ICONIX2; B: ICONIX2/Stryker ReelX 3.9mm; C: ICONIX2/Stryker ReelX 4.5mm; D: Arthrex BioComposite CorkScrew FT 4.5mm/Arthrex BioComposite SwiveLock 4.75mm. The ICONIX2 was the only all-suture anchor tested. Tendons underwent cyclic loading from 10 to 100N for 500 cycles, followed by load-to-failure. Data was collected at cycles 5, 100, 200, 300, 400, and 500. One-way ANOVA analysis was used to assess significance (P≤0.05). The anchor combinations tested did not differ significantly in anterior (P>0.4) or posterior (P>0.3) gap formation, construct stiffness (P>0.7), ultimate load (P=0.06), or load to 5mm gap formation (P=0.84). The all-suture anchor demonstrated comparable biomechanical performance in multiple double-row anchor combinations to a combination of traditional solid-body anchors. Thus it may be an attractive option to further reduce the invasiveness of rotator cuff repairs. Copyright © 2015 Elsevier Ltd. All rights reserved.

  4. New 'one-step' method for the simultaneous synthesis and anchoring of organic monolith inside COC microchip channels

    International Nuclear Information System (INIS)

    Ladner, Yoann; Cretier, Gerard; Dugas, Vincent; Randon, Jerome; Faure, Karine; Bruchet, Anthony

    2012-01-01

    A new method for monolith synthesis and anchoring inside cyclic olefin copolymer (COC) microchannels in a single step is proposed. It is shown that type I photo-initiators, typically used in a polymerization mixture to generate free radicals during monolith synthesis, can simultaneously act as type II photo-initiators and react with the plastic surface through hydrogen abstraction. This mechanism is used to 'photo-graft' poly(ethylene glycol) methacrylate (PEGMA) on COC surfaces. Contact angle measurements were used to observe the changes in surface hydrophilicity when increasing initiator concentration and irradiation duration. The ability of type I photo-initiators to synthesize and anchor a monolith inside COC microchannels in a single step was proved through SEM observations. Different concentrations of photo-initiators were tried. Finally, electro-chromatographic separations of polycyclic aromatic hydrocarbons were realized to illustrate the beneficial effect of anchoring on chromatographic performances. The versatility of the method was demonstrated with two widely used photo-initiators: benzoin methyl ether (BME) and azobisisobutyronitrile (AIBN). (authors)

  5. Poor Anchoring Limits Dyslexics' Perceptual, Memory, and Reading Skills

    Science.gov (United States)

    Oganian, Yulia; Ahissar, Merav

    2012-01-01

    The basic deficits underlying the severe and persistent reading difficulties in dyslexia are still highly debated. One of the major topics of debate is whether these deficits are language specific, or affect both verbal and non-verbal stimuli. Recently, Ahissar and colleagues proposed the "anchoring-deficit hypothesis" (Ahissar, Lubin,…

  6. ER-mitochondria contacts control surface glycan expression and sensitivity to killer lymphocytes in glioma stem-like cells.

    Science.gov (United States)

    Bassoy, Esen Yonca; Kasahara, Atsuko; Chiusolo, Valentina; Jacquemin, Guillaume; Boydell, Emma; Zamorano, Sebastian; Riccadonna, Cristina; Pellegatta, Serena; Hulo, Nicolas; Dutoit, Valérie; Derouazi, Madiha; Dietrich, Pierre Yves; Walker, Paul R; Martinvalet, Denis

    2017-06-01

    Glioblastoma is a highly heterogeneous aggressive primary brain tumor, with the glioma stem-like cells (GSC) being more sensitive to cytotoxic lymphocyte-mediated killing than glioma differentiated cells (GDC). However, the mechanism behind this higher sensitivity is unclear. Here, we found that the mitochondrial morphology of GSCs modulates the ER-mitochondria contacts that regulate the surface expression of sialylated glycans and their recognition by cytotoxic T lymphocytes and natural killer cells. GSCs displayed diminished ER-mitochondria contacts compared to GDCs. Forced ER-mitochondria contacts in GSCs increased their cell surface expression of sialylated glycans and reduced their susceptibility to cytotoxic lymphocytes. Therefore, mitochondrial morphology and dynamism dictate the ER-mitochondria contacts in order to regulate the surface expression of certain glycans and thus play a role in GSC recognition and elimination by immune effector cells. Targeting the mitochondrial morphology, dynamism, and contacts with the ER could be an innovative strategy to deplete the cancer stem cell compartment to successfully treat glioblastoma. © 2017 The Authors.

  7. Sialylation potentials of the silkworm, Bombyx mori; B. mori possesses an active α2,6-sialyltransferase.

    Science.gov (United States)

    Kajiura, Hiroyuki; Hamaguchi, Yuichi; Mizushima, Hiroki; Misaki, Ryo; Fujiyama, Kazuhito

    2015-12-01

    N-Glycosylation is an important post-translational modification in most secreted and membrane-bound proteins in eukaryotic cells. However, the insect N-glycosylation pathway and the potentials contributing to the N-glycan synthesis are still unclear because most of the studies on these subjects have focused on mammals and plants. Here, we identified Bombyx mori sialyltransferase (BmST), which is a Golgi-localized glycosyltransferase and which can modify N-glycans. BmST was ubiquitously expressed in different organs and in various stages of development and localized at the Golgi. Biochemical analysis using Sf9-expressed BmST revealed that BmST encoded α2,6-sialyltransferase and transferred N-acetylneuraminic acid (NeuAc) to the nonreducing terminus of Galβ1-R, but exhibited the highest activity toward GalNAcβ1,4-GlcNAc-R. Unlike human α2,6-sialyltransferase, BmST required the post-translational modification, especially N-glycosylation, for its full activity. N-Glycoprotein analysis of B. mori fifth instar larvae revealed that high-mannose-type structure was predominant and GlcNAc-linked and fucosylated structures were observed but endogenous galactosyl-, N-acetylgalactosaminyl- and sialyl-N-glycoproteins were undetectable under the standard analytical approach. These results indicate that B. mori genome encodes an α2,6-sialyltransferase, but further investigations of the sialylation potentials are necessary. © The Author 2015. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  8. Monogenean anchor morphometry: systematic value, phylogenetic signal, and evolution

    Science.gov (United States)

    Soo, Oi Yoon Michelle; Tan, Wooi Boon; Lim, Lee Hong Susan

    2016-01-01

    Background. Anchors are one of the important attachment appendages for monogenean parasites. Common descent and evolutionary processes have left their mark on anchor morphometry, in the form of patterns of shape and size variation useful for systematic and evolutionary studies. When combined with morphological and molecular data, analysis of anchor morphometry can potentially answer a wide range of biological questions. Materials and Methods. We used data from anchor morphometry, body size and morphology of 13 Ligophorus (Monogenea: Ancyrocephalidae) species infecting two marine mugilid (Teleostei: Mugilidae) fish hosts: Moolgarda buchanani (Bleeker) and Liza subviridis (Valenciennes) from Malaysia. Anchor shape and size data (n = 530) were generated using methods of geometric morphometrics. We used 28S rRNA, 18S rRNA, and ITS1 sequence data to infer a maximum likelihood phylogeny. We discriminated species using principal component and cluster analysis of shape data. Adams’s Kmult was used to detect phylogenetic signal in anchor shape. Phylogeny-correlated size and shape changes were investigated using continuous character mapping and directional statistics, respectively. We assessed morphological constraints in anchor morphometry using phylogenetic regression of anchor shape against body size and anchor size. Anchor morphological integration was studied using partial least squares method. The association between copulatory organ morphology and anchor shape and size in phylomorphospace was used to test the Rohde-Hobbs hypothesis. We created monogeneaGM, a new R package that integrates analyses of monogenean anchor geometric morphometric data with morphological and phylogenetic data. Results. We discriminated 12 of the 13 Ligophorus species using anchor shape data. Significant phylogenetic signal was detected in anchor shape. Thus, we discovered new morphological characters based on anchor shaft shape, the length between the inner root point and the outer root

  9. The Holding Power of Anchors

    Indian Academy of Sciences (India)

    The efficiency of an anchor may be expressed as the ratio (holding force + weight of anchor). In dry sand .... the market at the beginning of the coming season in three sizes, namely 20, 35 and. 60 lb. These are ... Taylor frozen-flow hypothesis.

  10. Post-Golgi anterograde transport requires GARP-dependent endosome-to-TGN retrograde transport

    Science.gov (United States)

    Hirata, Tetsuya; Fujita, Morihisa; Nakamura, Shota; Gotoh, Kazuyoshi; Motooka, Daisuke; Murakami, Yoshiko; Maeda, Yusuke; Kinoshita, Taroh

    2015-01-01

    The importance of endosome-to–trans-Golgi network (TGN) retrograde transport in the anterograde transport of proteins is unclear. In this study, genome-wide screening of the factors necessary for efficient anterograde protein transport in human haploid cells identified subunits of the Golgi-associated retrograde protein (GARP) complex, a tethering factor involved in endosome-to-TGN transport. Knockout (KO) of each of the four GARP subunits, VPS51–VPS54, in HEK293 cells caused severely defective anterograde transport of both glycosylphosphatidylinositol (GPI)-anchored and transmembrane proteins from the TGN. Overexpression of VAMP4, v-SNARE, in VPS54-KO cells partially restored not only endosome-to-TGN retrograde transport, but also anterograde transport of both GPI-anchored and transmembrane proteins. Further screening for genes whose overexpression normalized the VPS54-KO phenotype identified TMEM87A, encoding an uncharacterized Golgi-resident membrane protein. Overexpression of TMEM87A or its close homologue TMEM87B in VPS54-KO cells partially restored endosome-to-TGN retrograde transport and anterograde transport. Therefore GARP- and VAMP4-dependent endosome-to-TGN retrograde transport is required for recycling of molecules critical for efficient post-Golgi anterograde transport of cell-surface integral membrane proteins. In addition, TMEM87A and TMEM87B are involved in endosome-to-TGN retrograde transport. PMID:26157166

  11. Interaction of angiotensin-converting enzyme (ACE) with membrane-bound carboxypeptidase M (CPM) - a new function of ACE.

    Science.gov (United States)

    Sun, Xiaoou; Wiesner, Burkhard; Lorenz, Dorothea; Papsdorf, Gisela; Pankow, Kristin; Wang, Po; Dietrich, Nils; Siems, Wolf-Eberhard; Maul, Björn

    2008-12-01

    Angiotensin-converting enzyme (ACE) demonstrates, besides its typical dipeptidyl-carboxypeptidase activity, several unusual functions. Here, we demonstrate with molecular, biochemical, and cellular techniques that the somatic wild-type murine ACE (mACE), stably transfected in Chinese Hamster Ovary (CHO) or Madin-Darby Canine Kidney (MDCK) cells, interacts with endogenous membranal co-localized carboxypeptidase M (CPM). CPM belongs to the group of glycosylphosphatidylinositol (GPI)-anchored proteins. Here we report that ACE, completely independent of its known dipeptidase activities, has GPI-targeted properties. Our results indicate that the spatial proximity between mACE and the endogenous CPM enables an ACE-evoked release of CPM. These results are discussed with respect to the recently proposed GPI-ase activity and function of sperm-bound ACE.

  12. 78 FR 45104 - Model Manufactured Home Installation Standards: Ground Anchor Installations

    Science.gov (United States)

    2013-07-26

    ... anchor capacity. In granular soils, large lateral movements may produce failure planes that can reduce..., Consumer protection, Intergovernmental relations, Manufactured homes, Reporting and recordkeeping... relative to the plane of the ground surface and shall be permitted to be rounded to the nearest 5-degree...

  13. InterProScan Result: FS774270 [KAIKOcDNA[Archive

    Lifescience Database Archive (English)

    Full Text Available FS774270 FS774270_5_ORF1 FB109746C115A036 PFAM PF04114 Gaa1 NA ? IPR007246 unintegrated Cellular... Component: integral to membrane (GO:0016021)|Cellular Component: GPI-anchor transamidase complex (GO:0042765) ...

  14. InterProScan Result: CK559994 [KAIKOcDNA[Archive

    Lifescience Database Archive (English)

    Full Text Available CK559994 CK559994_4_ORF2 020DFCD801EB69C2 PFAM PF04114 Gaa1 NA ? IPR007246 unintegrated Cellular... Component: integral to membrane (GO:0016021)|Cellular Component: GPI-anchor transamidase complex (GO:0042765) ...

  15. Enhanced Charge Separation Efficiency in Pyridine-Anchored Phthalocyanine-Sensitized Solar Cells by Linker Elongation.

    Science.gov (United States)

    Ikeuchi, Takuro; Agrawal, Saurabh; Ezoe, Masayuki; Mori, Shogo; Kimura, Mutsumi

    2015-11-01

    A series of zinc phthalocyanine sensitizers (PcS22-24) having a pyridine anchoring group are designed and synthesized to investigate the structural dependence on performance in dye-sensitized solar cells. The pyridine-anchor zinc phthalocyanine sensitizer PcS23 shows 79 % incident-photon to current-conversion efficiency (IPCE) and 6.1 % energy conversion efficiency, which are comparable with similar phthalocyanine dyes having a carboxylic acid anchoring group. Based on DFT calculations, the high IPCE is attributed with the mixture of an excited-state molecular orbital of the sensitizer and the orbitals of TiO2 . Between pyridine and carboxylic acid anchor dyes, opposite trends are observed in the linker-length dependence of the IPCE. The red-absorbing PcS23 is applied for co-sensitization with a carboxyl-anchor organic dye D131 that has a complementary spectral response. The site-selective adsorption of PcS23 and D131 on the TiO2 surface results in a panchromatic photocurrent response for the whole visible-light region of sun light. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  16. Anchoring effects on early autobiographical memories.

    Science.gov (United States)

    Greenberg, Daniel L; Bishara, Anthony J; Mugayar-Baldocchi, Marino A

    2017-10-01

    Studies of childhood memory typically show that our earliest memories come from between three and four years of age. This finding is not universal, however. The age estimate varies across cultures and is affected by social influences. Research from the judgments and decision-making literature suggests that these estimates might also involve a judgment under uncertainty. Therefore, they might be susceptible to less social influences such as heuristics and biases. To investigate this possibility, we conducted two experiments that used anchoring paradigms to influence participants' estimates of their age during early autobiographical memories. In Experiment 1, participants answered either a high-anchor or a low-anchor question, and were warned that the anchor was uninformative; they went on to estimate their age during their earliest autobiographical memory. In Experiment 2, we replicated Experiment 1 and extended the design to examine additional early autobiographical memories. In both experiments, participants in the low-anchor condition gave earlier age estimates than those in the high-anchor condition. These results provide new insights into the methods used to investigate autobiographical memory. Moreover, they show that reports of early autobiographical memories can be influenced by a relatively light touch - a change to a single digit in a single question.

  17. Glycosylphosphatidylinositol-Anchored Anti-HIV scFv Efficiently Protects CD4 T Cells from HIV-1 Infection and Deletion in hu-PBL Mice

    Science.gov (United States)

    Ye, Chaobaihui; Wang, Weiming; Cheng, Liang; Li, Guangming; Wen, Michael; Wang, Qi; Zhang, Qing; Li, Dan

    2016-01-01

    ABSTRACT Despite success in viral inhibition and CD4 T cell recovery by highly active antiretroviral treatment (HAART), HIV-1 is still not curable due to the persistence of the HIV-1 reservoir during treatment. One patient with acute myeloid leukemia who received allogeneic hematopoietic stem cell transplantation from a homozygous CCR5 Δ32 donor has had no detectable viremia for 9 years after HAART cessation. This case has inspired a field of HIV-1 cure research focusing on engineering HIV-1 resistance in permissive cells. Here, we employed a glycosylphosphatidylinositol (GPI)-scFv X5 approach to confer resistance of human primary CD4 T cells to HIV-1. We showed that primary CD4 T cells expressing GPI-scFv X5 were resistant to CCR5 (R5)-, CXCR4 (X4)-, and dual-tropic HIV-1 and had a survival advantage compared to control cells ex vivo. In a hu-PBL mouse study, GPI-scFv X5-transduced CD4 T cells were selected in peripheral blood and lymphoid tissues upon HIV-1 infection. Finally, GPI-scFv X5-transduced CD4 T cells, after being cotransfused with HIV-infected cells, showed significantly reduced viral loads and viral RNA copy numbers relative to CD4 cells in hu-PBL mice compared to mice with GPI-scFv AB65-transduced CD4 T cells. We conclude that GPI-scFv X5-modified CD4 T cells could potentially be used as a genetic intervention against both R5- and X4-tropic HIV-1 infections. IMPORTANCE Blocking of HIV-1 entry is one of most promising approaches for therapy. Genetic disruption of the HIV-1 coreceptor CCR5 by nucleases in T cells is under 2 clinical trials and leads to reduced viremia in patients. However, the emergence of viruses using the CXCR4 coreceptor is a concern for therapies applying single-coreceptor disruption. Here, we report that HIV-1-permissive CD4 T cells engineered with GPI-scFv X5 are resistant to R5-, X4-, or dual-tropic virus infection ex vivo. In a preclinical study using hu-PBL mice, we show that CD4 T cells were protected and that GPI-scFv X5

  18. Preclinical evaluation of the saponin derivative GPI-0100 as an immunostimulating and dose-sparing adjuvant for pandemic influenza vaccines

    NARCIS (Netherlands)

    Liu, Heng; Bungener, Laura; ter Veer, Wouter; Coller, Beth-Ann; Wilschut, Jan; Huckriede, Anke

    2011-01-01

    With the current global influenza vaccine production capacity the large demand for vaccines in case of a pandemic can only be fulfilled when antigen dose sparing strategies are employed. Here we used a murine challenge model to evaluate the potential of GPI-0100, a semi-synthetic saponin derivative,

  19. Immunization of breast cancer patients using a synthetic sialyl-Tn glycoconjugate plus Detox adjuvant.

    Science.gov (United States)

    MacLean, G D; Reddish, M; Koganty, R R; Wong, T; Gandhi, S; Smolenski, M; Samuel, J; Nabholtz, J M; Longenecker, B M

    1993-01-01

    We have synthesized various formulations that have potential for active specific immunotherapy (ASI) of human cancers. Sialyl-Tn (STn) is a potentially important target structure for ASI because its expression on mucins is a strong, independent predictor of poor prognosis, suggesting that it may have functional significance in the metastatic process. In this first pilot study of synthetic sialyl-Tn hapten conjugated to keyhole limpet hemocyanin (STn-KLH), with Detox adjuvant, toxicity and humoral immunogenicity were assessed in 12 patients with metastatic breast cancer. Toxicity was minimal, restricted to local cutaneous reactions (apart from transient nausea and vomiting following single low-dose cyclophosphamide treatment). Using STn-conjugated human serum albumin in a solid-phase enzyme-linked immunosorbent assay, it was shown that all patients developed IgM and IgG specific for the synthetic STn hapten. Following immunization, most patients were shown to develop increased titres of complement-mediated cytotoxic antibodies, partially inhibited by synthetic STn hapten, but not by the related TF hapten. We also detected IgM and IgG antibodies reactive with natural STn determinants expressed on ovine submaxillary mucin, the STn specificity of this reactivity being confirmed by hapten inhibition. Evaluation of clinical efficacy in a small pilot study is difficult. Five patients are alive 12 or more months after entry, and another 4 patients are alive 6 or more months after entry into the study. All 3 patients with known widespread bulky disease progressed despite ASI, 2 having died from widespread cancer. Two patients had partial responses, each lasting 6 months. While several patients had disease stability for 3-10 months, 1 patient with pulmonary metastases remains stable 15 months after entry into the program.

  20. An earth anchor system: installation and design guide.

    Science.gov (United States)

    R.L. Copstead; D.D. Studier

    1990-01-01

    A system for anchoring the guylines and skylines of cable yarding equipment is presented. A description of three types of tipping plate anchors is given. Descriptions of the installation equipment and methods specific to each type are given. Procedures for determining the correct number of anchors to install are included, as are guidelines for installing the anchors so...

  1. Towards robot-assisted anchor deployment in beating-heart mitral valve surgery.

    Science.gov (United States)

    Cheng, Lingbo; Sharifi, Mojtaba; Tavakoli, Mahdi

    2018-06-01

    Beating-heart intracardiac surgery promises significant benefits for patients compared with cardiopulmonary bypass based procedures. However, the fast motions of the heart introduce serious challenges for surgeons. In this work, a new impedance-controlled master-slave telerobotic system is developed to help perform anchor deployment for mitral valve annuloplasty under the guidance of live ultrasound images of the heart. The proposed bilateral teleoperation system can both reflect the non-oscillatory portion of slave-heart tissue interaction force on the surgeon's hand as haptic feedback and implement rapid compensation for the beating heart's motion. The surgical task involves performing anchor deployment on a simulated moving heart tissue to evaluate the effectiveness of the proposed strategy for safely interacting with a moving organ. The results obtained show that the telerobotic system increases the success rate of anchor deployment by 100% and reduces the excess force application rate by 70% compared with manual attempts. Copyright © 2018 John Wiley & Sons, Ltd.

  2. Exploring the Strengths and Limits of Strong and Weak Sustainability Indicators: A Case Study of the Assessment of China’s Megacities with EF and GPI

    Directory of Open Access Journals (Sweden)

    Lu Huang

    2018-01-01

    Full Text Available The perspective of strong/weak sustainability has a great impact on sustainability assessment. In this study, two most widely used indices, Ecological Footprint (EF and Genuine Progress Indicator (GPI for strong and weak sustainability assessment, were employed to evaluate the sustainability of China’s ten megacities between 1978 and 2015. The results showed that the ecological footprint had been enlarged in the past twenty years; while the genuine economic welfare started to increase since 2005. The cities of Xi’an, Chengdu, Chongqing, and Shanghai met the threshold of below 2.5 global hectares for EF/capita, and over 3000 dollars/capita (in 2010 US$ for GPI/capita. By analyzing and comparing the characteristics, the processes and results, and the complementary features of evaluation methods of EF and GPI, the research suggested that: (1 Strong and weak sustainability indicators, with their own pros/cons in sustainability assessment, should be used carefully; (2 Weak sustainability indicators could be analyzed from the perspective of strong sustainability; (3 Strong sustainability indicators need to be developed urgently. The results in this study could guide the selection of sustainability indicators, and help interpret the results of sustainability assessment.

  3. Anchored LH2 complexes in 2D polarization imaging.

    Science.gov (United States)

    Tubasum, Sumera; Sakai, Shunsuke; Dewa, Takehisa; Sundström, Villy; Scheblykin, Ivan G; Nango, Mamoru; Pullerits, Tõnu

    2013-09-26

    Protein is a soft material with inherently large structural disorder. Consequently, the bulk spectroscopies of photosynthetic pigment protein complexes provide averaged information where many details are lost. Here we report spectroscopy of single light-harvesting complexes where fluorescence excitation and detection polarizations are both independently rotated. Two samples of peripheral antenna (LH2) complexes from Rhodopseudomonas acidophila were studied. In one, the complexes were embedded in polyvinyl alcohol (PVA) film; in the other, they were anchored on the glass surface and covered by the PVA film. LH2 contains two rings of pigment molecules-B800 and B850. The B800 excitation polarization properties of the two samples were found to be very similar, indicating that orientation statistics of LH2s are the same in these two very different preparations. At the same time, we found a significant difference in B850 emission polarization statistics. We conclude that the B850 band of the anchored sample is substantially more disordered. We argue that both B800 excitation and B850 emission polarization properties can be explained by the tilt of the anchored LH2s due to the spin-casting of the PVA film on top of the complexes and related shear forces. Due to the tilt, the orientation statistics of two samples become similar. Anchoring is expected to orient the LH2s so that B850 is closer to the substrate. Consequently, the tilt-related strain leads to larger deformation and disorder in B850 than in B800.

  4. Evolutionary morphology in shape and size of haptoral anchors in 14 Ligophorus spp. (Monogenea: Dactylogyridae).

    Science.gov (United States)

    Rodríguez-González, Abril; Sarabeev, Volodimir; Balbuena, Juan Antonio

    2017-01-01

    The search for phylogenetic signal in morphological traits using geometric morphometrics represents a powerful approach to estimate the relative weights of convergence and shared evolutionary history in shaping organismal form. We assessed phylogenetic signal in the form of ventral and dorsal haptoral anchors of 14 species of Ligophorus occurring on grey mullets (Osteichthyes: Mugilidae) from the Mediterranean, the Black Sea and the Sea of Azov. The phylogenetic relationships among these species were mapped onto the morphospaces of shape and size of dorsal and ventral anchors and two different tests were applied to establish whether the spatial positions in the morphospace were dictated by chance. Overall significant phylogenetic signal was found in the data. Allometric effects on anchor shape were moderate or non-significant in the case of evolutionary allometry. Relatively phylogenetically distant species occurring on the same host differed markedly in anchor morphology indicating little influence of host species on anchor form. Our results suggest that common descent and shared evolutionary history play a major role in determining the shape and, to a lesser degree in the size of haptoral anchors in Ligophorus spp. The present approach allowed tracing paths of morphological evolution in anchor shape. Species with narrow anchors and long shafts were associated predominately with Liza saliens. This morphology was considered to be ancestral relative to anchors of species occurring on Liza haematocheila and M. cephalus possessing shorter shafts and longer roots. Evidence for phylogenetic signal was more compelling for the ventral anchors, than for the dorsal ones, which could reflect different functional roles in attachment to the gills. Although phylogeny and homoplasy may act differently in other monogeneans, the present study delivers a common framework to address effectively the relationships among morphology, phylogeny and other traits, such as host specificity

  5. Evolutionary morphology in shape and size of haptoral anchors in 14 Ligophorus spp. (Monogenea: Dactylogyridae.

    Directory of Open Access Journals (Sweden)

    Abril Rodríguez-González

    Full Text Available The search for phylogenetic signal in morphological traits using geometric morphometrics represents a powerful approach to estimate the relative weights of convergence and shared evolutionary history in shaping organismal form. We assessed phylogenetic signal in the form of ventral and dorsal haptoral anchors of 14 species of Ligophorus occurring on grey mullets (Osteichthyes: Mugilidae from the Mediterranean, the Black Sea and the Sea of Azov. The phylogenetic relationships among these species were mapped onto the morphospaces of shape and size of dorsal and ventral anchors and two different tests were applied to establish whether the spatial positions in the morphospace were dictated by chance. Overall significant phylogenetic signal was found in the data. Allometric effects on anchor shape were moderate or non-significant in the case of evolutionary allometry. Relatively phylogenetically distant species occurring on the same host differed markedly in anchor morphology indicating little influence of host species on anchor form. Our results suggest that common descent and shared evolutionary history play a major role in determining the shape and, to a lesser degree in the size of haptoral anchors in Ligophorus spp. The present approach allowed tracing paths of morphological evolution in anchor shape. Species with narrow anchors and long shafts were associated predominately with Liza saliens. This morphology was considered to be ancestral relative to anchors of species occurring on Liza haematocheila and M. cephalus possessing shorter shafts and longer roots. Evidence for phylogenetic signal was more compelling for the ventral anchors, than for the dorsal ones, which could reflect different functional roles in attachment to the gills. Although phylogeny and homoplasy may act differently in other monogeneans, the present study delivers a common framework to address effectively the relationships among morphology, phylogeny and other traits, such

  6. Improving performance by anchoring movement and "nerves".

    Science.gov (United States)

    Iso-Ahola, Seppo E; Dotson, Charles O; Jagodinsky, Adam E; Clark, Lily C; Smallwood, Lorraine L; Wilburn, Christopher; Weimar, Wendi H; Miller, Matthew W

    2016-10-01

    Golf's governing bodies' recent decision to ban all putting styles "anchoring one end of the club against the body" bridges an important practical problem with psychological theory. We report the first experiment testing whether anchoring provides technical and/or psychological advantage in competitive performance. Many "greats" of professional golf from Arnold Palmer and Jack Nicklaus to Tiger Woods have argued against anchoring, believing that it takes "nerves" out of competitive performance and therefore artificially levels the playing field. To shed more light on the issue, we tested participants' performance with anchored and unanchored putters under low and high pressure when controlling for the putter length. We found no statistically significant evidence for a technical advantage due to anchoring but a clear psychological advantage: participants who anchored their putters significantly outperformed unanchored counterparts under high, but not low, pressure. Results provide tentative evidence for the ban's justification from a competitive standpoint. However, before any definite conclusions can be made, more research is needed when using high-level golfers. Copyright © 2016 Elsevier B.V. All rights reserved.

  7. Testing and modeling of cyclically loaded rock anchors

    Directory of Open Access Journals (Sweden)

    Joar Tistel

    2017-12-01

    Full Text Available The Norwegian Public Roads Administration (NPRA is planning for an upgrade of the E39 highway route at the westcoast of Norway. Fixed links shall replace ferries at seven fjord crossings. Wide spans and large depths at the crossings combined with challenging subsea topography and environmental loads call for an extension of existing practice. A variety of bridge concepts are evaluated in the feasibility study. The structures will experience significant loads from deadweight, traffic and environment. Anchoring of these forces is thus one of the challenges met in the project. Large-size subsea rock anchors are considered a viable alternative. These can be used for anchoring of floating structures but also with the purpose of increasing capacity of fixed structures. This paper presents first a thorough study of factors affecting rock anchor bond capacity. Laboratory testing of rock anchors subjected to cyclic loading is thereafter presented. Finally, the paper presents a model predicting the capacity of a rock anchor segment, in terms of a ribbed bar, subjected to a cyclic load history. The research assumes a failure mode occurring in the interface between the rock anchor and the surrounding grout. The constitutive behavior of the bonding interface is investigated for anchors subjected to cyclic one-way tensile loads. The model utilizes the static bond capacity curve as a basis, defining the ultimate bond τbu and the slip s1 at τbu. A limited number of input parameters are required to apply the model. The model defines the bond-slip behavior with the belonging rock anchor capacity depending on the cyclic load level (τmax cy/τbu, the cyclic load ratio (R = τmin cy/τmax cy, and the number of load cycles (N. The constitutive model is intended to model short anchor lengths representing an incremental length of a complete rock anchor.

  8. Lower limit of strength wedge-type anchor bolts

    International Nuclear Information System (INIS)

    Arnedo Pena, A.; Frances Urmeneta, M.

    1998-01-01

    Simple expansion bolts, with a split expansion ring and a threaded bolt with an integral cone expander, called wedge type, are very used in securing and anchoring structures. The anchorage is obtained by a mechanism of torque-controlled expansion. Although less resistant than other types, its easy installation and low cost make them very competitive in light structures. In this paper, the minimum capacity values are analysed, when they are used to anchor safety-related equipment in NPP. The EPRI criteria developed in response to USI A-46 are applied and complemented by the new CEB Anchorage Design Guide. The results are compared with the information from european manufactures, adopting different safety factors for cracked and non-cracked concrete. With adequate control and inspection measures, including areas of noticeable cracking of concrete. minimum values for equipment can be obtained satisfying the strictest seismic validation requirements. (Author) 5 refs

  9. Influence of Anchoring on Burial Depth of Submarine Pipelines.

    Science.gov (United States)

    Zhuang, Yuan; Li, Yang; Su, Wei

    2016-01-01

    Since the beginning of the twenty-first century, there has been widespread construction of submarine oil-gas transmission pipelines due to an increase in offshore oil exploration. Vessel anchoring operations are causing more damage to submarine pipelines due to shipping transportation also increasing. Therefore, it is essential that the influence of anchoring on the required burial depth of submarine pipelines is determined. In this paper, mathematical models for ordinary anchoring and emergency anchoring have been established to derive an anchor impact energy equation for each condition. The required effective burial depth for submarine pipelines has then been calculated via an energy absorption equation for the protection layer covering the submarine pipelines. Finally, the results of the model calculation have been verified by accident case analysis, and the impact of the anchoring height, anchoring water depth and the anchor weight on the required burial depth of submarine pipelines has been further analyzed.

  10. The loss of luteal progesterone production in women is associated with a galectin switch via α2,6-sialylation of glycoconjugates.

    Science.gov (United States)

    Nio-Kobayashi, Junko; Boswell, Lyndsey; Amano, Maho; Iwanaga, Toshihiko; Duncan, W Colin

    2014-12-01

    Luteal progesterone is fundamental for reproduction, but the molecular regulation of the corpus luteum (CL) in women remains unclear. Galectin-1 and galectin-3 bind to the sugar chains on cells to control key biological processes including cell function and fate. The expression and localization of LGALS1 and LGALS3 were analyzed by quantitative PCR and histochemical analysis, with special reference to α2,6-sialylation of glycoconjugates in carefully dated human CL collected across the menstrual cycle and after exposure to human chorionic gonadotrophin (hCG) in vivo. The effects of hCG and prostaglandin E2 on the expression of galectins and an α2,6-sialyltransferase 1 (ST6GAL1) in granulosa lutein cells were analyzed in vitro. Galectin-1 was predominantly localized to healthy granulosa lutein cells and galectin-3 was localized to macrophages and regressing granulosa lutein cells. Acute exposure to luteotrophic hormones (hCG and prostaglandin E2) up-regulated LGALS1 expression (P progesterone synthesis. Luteotrophic hormones differentially regulate galectin-1 and galectin-3/α2,6-sialylation in granulosa lutein cells, suggesting a novel galectin switch regulated by luteotrophic stimuli during luteolysis and luteal rescue.

  11. Study on monitoring of deep foundation pit with SMW engineering method plus anchor cable retaining structure

    Science.gov (United States)

    Chen, Wenzhao; Cui, Wenping

    2018-03-01

    The SMW method has many advantages, such as little influence on the surrounding environment, good watertight performance, wide range of application, short construction period, low cost and so on. In this paper, we chose the SMW engineering method combined with anchor cable to support structure in the second phase deep foundation pit of Jinan LuJinDongCheng as the research object, monitored and analysed the horizontal displacement of the pile top, Peripheral surface subsidence and internal force of the anchor cable in the foundation pit. We also discussed the displacement, internal force of anchor cable and the settlement of surrounding environment in the excavation of foundation pit and in different stages of construction. Conclusion:(1)The maximum horizontal displacement of the retaining structure is closely related to the depth and time of excavation, the construction of anchor cable can well limit the deformation of pile body; (2)Groundwater seepage caused by foundation pit dewatering will change the effective stress of soil. The change of groundwater level has an important influence on the working behavior of smw anchor cable supporting structure.

  12. Chilling of Dormant Buds Hyperinduces FLOWERING LOCUS T and Recruits GA-Inducible 1,3-β-Glucanases to Reopen Signal Conduits and Release Dormancy in Populus[W][OA

    Science.gov (United States)

    Rinne, Päivi L.H.; Welling, Annikki; Vahala, Jorma; Ripel, Linda; Ruonala, Raili; Kangasjärvi, Jaakko; van der Schoot, Christiaan

    2011-01-01

    In trees, production of intercellular signals and accessibility of signal conduits jointly govern dormancy cycling at the shoot apex. We identified 10 putative cell wall 1,3-β-glucanase genes (glucan hydrolase family 17 [GH17]) in Populus that could turn over 1,3-β-glucan (callose) at pores and plasmodesmata (PD) and investigated their regulation in relation to FT and CENL1 expression. The 10 genes encode orthologs of Arabidopsis thaliana BG_ppap, a PD-associated glycosylphosphatidylinositol (GPI) lipid-anchored protein, the Arabidopsis PD callose binding protein PDCB, and a birch (Betula pendula) putative lipid body (LB) protein. We found that these genes were differentially regulated by photoperiod, by chilling (5°C), and by feeding of gibberellins GA3 and GA4. GA3 feeding upregulated all LB-associated GH17s, whereas GA4 upregulated most GH17s with a GPI anchor and/or callose binding motif, but only GA4 induced true bud burst. Chilling upregulated a number of GA biosynthesis and signaling genes as well as FT, but not CENL1, while the reverse was true for both GA3 and GA4. Collectively, the results suggest a model for dormancy release in which chilling induces FT and both GPI lipid-anchored and GA3-inducible GH17s to reopen signaling conduits in the embryonic shoot. When temperatures rise, the reopened conduits enable movement of FT and CENL1 to their targets, where they drive bud burst, shoot elongation, and morphogenesis. PMID:21282527

  13. Chilling of dormant buds hyperinduces FLOWERING LOCUS T and recruits GA-inducible 1,3-beta-glucanases to reopen signal conduits and release dormancy in Populus.

    Science.gov (United States)

    Rinne, Päivi L H; Welling, Annikki; Vahala, Jorma; Ripel, Linda; Ruonala, Raili; Kangasjärvi, Jaakko; van der Schoot, Christiaan

    2011-01-01

    In trees, production of intercellular signals and accessibility of signal conduits jointly govern dormancy cycling at the shoot apex. We identified 10 putative cell wall 1,3-β-glucanase genes (glucan hydrolase family 17 [GH17]) in Populus that could turn over 1,3-β-glucan (callose) at pores and plasmodesmata (PD) and investigated their regulation in relation to FT and CENL1 expression. The 10 genes encode orthologs of Arabidopsis thaliana BG_ppap, a PD-associated glycosylphosphatidylinositol (GPI) lipid-anchored protein, the Arabidopsis PD callose binding protein PDCB, and a birch (Betula pendula) putative lipid body (LB) protein. We found that these genes were differentially regulated by photoperiod, by chilling (5°C), and by feeding of gibberellins GA(3) and GA(4). GA(3) feeding upregulated all LB-associated GH17s, whereas GA(4) upregulated most GH17s with a GPI anchor and/or callose binding motif, but only GA(4) induced true bud burst. Chilling upregulated a number of GA biosynthesis and signaling genes as well as FT, but not CENL1, while the reverse was true for both GA(3) and GA(4). Collectively, the results suggest a model for dormancy release in which chilling induces FT and both GPI lipid-anchored and GA(3)-inducible GH17s to reopen signaling conduits in the embryonic shoot. When temperatures rise, the reopened conduits enable movement of FT and CENL1 to their targets, where they drive bud burst, shoot elongation, and morphogenesis.

  14. Ringstone anchors from Gujarat, west coast of India

    Digital Repository Service at National Institute of Oceanography (India)

    Gaur, A.S.; Sundaresh; Tripati, S.; Bandodkar, S.N.

    of Dwarka and Somanath have yielded several ringstone anchors along with other stone anchors such as triangular and grapnel types. The raw material used for these ring stones comprises basalt, sandstone and limestone. Earlier, these anchors were identified...

  15. Influence of Anchoring on Burial Depth of Submarine Pipelines.

    Directory of Open Access Journals (Sweden)

    Yuan Zhuang

    Full Text Available Since the beginning of the twenty-first century, there has been widespread construction of submarine oil-gas transmission pipelines due to an increase in offshore oil exploration. Vessel anchoring operations are causing more damage to submarine pipelines due to shipping transportation also increasing. Therefore, it is essential that the influence of anchoring on the required burial depth of submarine pipelines is determined. In this paper, mathematical models for ordinary anchoring and emergency anchoring have been established to derive an anchor impact energy equation for each condition. The required effective burial depth for submarine pipelines has then been calculated via an energy absorption equation for the protection layer covering the submarine pipelines. Finally, the results of the model calculation have been verified by accident case analysis, and the impact of the anchoring height, anchoring water depth and the anchor weight on the required burial depth of submarine pipelines has been further analyzed.

  16. Silver nanoparticles anchored reduced graphene oxide for enhanced electrocatalytic activity towards methanol oxidation

    Science.gov (United States)

    Kumar, Sanjeev; Mahajan, Mani; Singh, Rajinder; Mahajan, Aman

    2018-02-01

    In this report, silver nanoparticles (Ag NPs) anchored reduced graphene oxide (rGO) sheets (rGO/Ag) nanohybrid has been explored as anode material in direct methanol fuel cells (DMFCs). The synthesized rGO/Ag nanohybrid is characterized by XRD, XPS, FTIR spectroscopy and HRTEM techniques. Cyclic voltammograms demonstrate that the rGO/Ag nanohybrid exhibits higher electrocatalytic activity in comparison to rGO sheets for methanol oxidation reaction (MOR). This enhancement is attributed to the synergetic effect produced by the presence of more active sites provided by Ag NPs anchored on a conducting network of large surface area rGO sheets.

  17. Two new FUT2 (fucosyltransferase 2 gene) missense polymorphisms, 739G-->A and 839T-->C, are partly responsible for non-secretor status in a Caucasian population from Northern Portugal.

    Science.gov (United States)

    Serpa, Jacinta; Mendes, Nuno; Reis, Celso A; Santos Silva, Luis F; Almeida, Raquel; Le Pendu, Jacques; David, Leonor

    2004-11-01

    Secretor status is defined by the expression of H type 1 antigen on gastric surface epithelium and external secretions. The H type 1 structure, and other fucosylated carbohydrates (Le(a), sialyl-Le(a), Le(b), Le(x), sialyl-Le(x) and Le(y)), can serve as ligands for several pathogens, including Helicobacter pylori, and are cancer-associated antigens. Secretor individuals are more susceptible to some bacterial and viral infections of the genito-urinary and digestive tracts. The aim of the present study was to examine FUT2 (fucosyltransferase 2 gene) polymorphisms in a Caucasian population of non-secretor individuals (n=36) from northern Portugal and to evaluate the activity of the mutant FUT2 enzymes. The secretor status was determined by UEAI [Ulex europaeus (gorse) lectin] histochemistry in gastric mucosa, and FUT2 polymorphisms were studied by restriction-fragment-length polymorphism and direct sequencing. The majority of non-secretors (88.9%) were homozygous for 428G-->A polymorphism; 5.6% were homozygous for 571C-->T and 5.6% were homozygous for two new missense polymorphisms, 739G-->A (2.8%) and 839T-->C (2.8%). By kinetic studies it was demonstrated that the two new FUT2 mutants (739G-->A and 839T-->C) are almost inactive and are responsible for some non-secretor cases.

  18. Protein-anchoring therapy to target extracellular matrix proteins to their physiological destinations.

    Science.gov (United States)

    Ito, Mikako; Ohno, Kinji

    2018-02-20

    Endplate acetylcholinesterase (AChE) deficiency is a form of congenital myasthenic syndrome (CMS) caused by mutations in COLQ, which encodes collagen Q (ColQ). ColQ is an extracellular matrix (ECM) protein that anchors AChE to the synaptic basal lamina. Biglycan, encoded by BGN, is another ECM protein that binds to the dystrophin-associated protein complex (DAPC) on skeletal muscle, which links the actin cytoskeleton and ECM proteins to stabilize the sarcolemma during repeated muscle contractions. Upregulation of biglycan stabilizes the DPAC. Gene therapy can potentially ameliorate any disease that can be recapitulated in cultured cells. However, the difficulty of tissue-specific and developmental stage-specific regulated expression of transgenes, as well as the difficulty of introducing a transgene into all cells in a specific tissue, prevents us from successfully applying gene therapy to many human diseases. In contrast to intracellular proteins, an ECM protein is anchored to the target tissue via its specific binding affinity for protein(s) expressed on the cell surface within the target tissue. Exploiting this unique feature of ECM proteins, we developed protein-anchoring therapy in which a transgene product expressed even in remote tissues can be delivered and anchored to a target tissue using specific binding signals. We demonstrate the application of protein-anchoring therapy to two disease models. First, intravenous administration of adeno-associated virus (AAV) serotype 8-COLQ to Colq-deficient mice, resulting in specific anchoring of ectopically expressed ColQ-AChE at the NMJ, markedly improved motor functions, synaptic transmission, and the ultrastructure of the neuromuscular junction (NMJ). In the second example, Mdx mice, a model for Duchenne muscular dystrophy, were intravenously injected with AAV8-BGN. The treatment ameliorated motor deficits, mitigated muscle histopathologies, decreased plasma creatine kinase activities, and upregulated expression

  19. Glycosylphosphatidylinositol-anchored CD4 supports human immunodeficiency virus type 1 replication, but not cytopathic effect, in T-cell transfectants.

    OpenAIRE

    Marshall, W L; Mittler, E S; Avery, P; Lawrence, J P; Finberg, R W

    1994-01-01

    Despite equivalent p24 antigen production, HSB-2 T cells expressing glycosylphosphatidylinositol (GPi)-linked CD4 were productively infected without cell death or syncytium formation, unlike HSB-2 transfectants expressing wild-type CD4 (wtCD4). HSB-2 transfectants dually expressing wtCD4 and GPi-linked CD4 formed syncytia and died. Thus, wtCD4 expression is critical for human immunodeficiency virus cytopathic effect in HSB-2 transfectants.

  20. The Use of Comics-Based Cases in Anchored Instruction

    Science.gov (United States)

    Kneller, Matthew F.

    2009-01-01

    The primary purpose of this research was to understand how comics fulfill the role of anchor in an anchored instruction learning environment. Anchored instruction addresses the inert knowledge problem through the use of realistic multimedia stories, or "anchors," that embed a problem and the necessary data to solve it within the narrative. In the…

  1. Effects of accuracy motivation and anchoring on metacomprehension judgment and accuracy.

    Science.gov (United States)

    Zhao, Qin

    2012-01-01

    The current research investigates how accuracy motivation impacts anchoring and adjustment in metacomprehension judgment and how accuracy motivation and anchoring affect metacomprehension accuracy. Participants were randomly assigned to one of six conditions produced by the between-subjects factorial design involving accuracy motivation (incentive or no) and peer performance anchor (95%, 55%, or no). Two studies showed that accuracy motivation did not impact anchoring bias, but the adjustment-from-anchor process occurred. Accuracy incentive increased anchor-judgment gap for the 95% anchor but not for the 55% anchor, which induced less certainty about the direction of adjustment. The findings offer support to the integrative theory of anchoring. Additionally, the two studies revealed a "power struggle" between accuracy motivation and anchoring in influencing metacomprehension accuracy. Accuracy motivation could improve metacomprehension accuracy in spite of anchoring effect, but if anchoring effect is too strong, it could overpower the motivation effect. The implications of the findings were discussed.

  2. Dynamic performance of concrete undercut anchors for Nuclear Power Plants

    Energy Technology Data Exchange (ETDEWEB)

    Mahrenholtz, Christoph, E-mail: christoph@mahrenholtz.net; Eligehausen, Rolf

    2013-12-15

    Graphical abstract: - Highlights: • Behavior of undercut anchors under dynamic actions simulating earthquakes. • First high frequency load and crack cycling tests on installed concrete anchors ever. • Comprehensive review of anchor qualification for Nuclear Power Plants. - Abstract: Post-installed anchors are widely used for structural and nonstructural connections to concrete. In many countries, concrete anchors used for Nuclear Power Plants have to be qualified to ensure reliable behavior even under extreme conditions. The tests required for qualification of concrete anchors are carried out at quasi-static loading rates well below the rates to be expected for dynamic actions deriving from earthquakes, airplane impacts or explosions. To investigate potentially beneficial effects of high loading rates and cycling frequencies, performance tests on installed undercut anchors were conducted. After introductory notes on anchor technology and a comprehensive literature review, this paper discusses the qualification of anchors for Nuclear Power Plants and the testing carried out to quantify experimentally the effects of dynamic actions on the load–displacement behavior of undercut anchors.

  3. Primary structure determination of five sialylated oligosaccharides derived from bronchial- mucus glycoproteins of patients suffering from cystic fibrosis. The occurrence of the NeuAcα(2→3)Galα(1→4)[Fucα(1→3)]GlcNAcα(1→.) structural element revealed by 500-MHz 1H NMR spectroscopy

    NARCIS (Netherlands)

    Vliegenthart, J.F.G.; Lamblin, G.; Boersma, A.; Klein, A.; Roussel, P.; Halbeek, H. van

    1984-01-01

    The structure of sialylated carbohydrate units of bronchial mucins obtained from cystic fibrosis patients was investigated by 500-MHz 1H NMR spectroscopy in conjunction with sugar analysis. After subjecting the mucins to alkaline borohydride degradation, sialylated oligosaccharide-alditols were

  4. A study of planar anchor groups for graphene-based single-molecule electronics.

    Science.gov (United States)

    Bailey, Steven; Visontai, David; Lambert, Colin J; Bryce, Martin R; Frampton, Harry; Chappell, David

    2014-02-07

    To identify families of stable planar anchor groups for use in single molecule electronics, we report detailed results for the binding energies of two families of anthracene and pyrene derivatives adsorbed onto graphene. We find that all the selected derivatives functionalized with either electron donating or electron accepting substituents bind more strongly to graphene than the parent non-functionalized anthracene or pyrene. The binding energy is sensitive to the detailed atomic alignment of substituent groups over the graphene substrate leading to larger than expected binding energies for -OH and -CN derivatives. Furthermore, the ordering of the binding energies within the anthracene and pyrene series does not simply follow the electron affinities of the substituents. Energy barriers to rotation or displacement on the graphene surface are much lower than binding energies for adsorption and therefore at room temperature, although the molecules are bound to the graphene, they are almost free to move along the graphene surface. Binding energies can be increased by incorporating electrically inert side chains and are sensitive to the conformation of such chains.

  5. A study of planar anchor groups for graphene-based single-molecule electronics

    Energy Technology Data Exchange (ETDEWEB)

    Bailey, Steven; Visontai, David; Lambert, Colin J., E-mail: c.lambert@lancaster.ac.uk [Department of Physics, Lancaster University, Lancaster LA1 4YB (United Kingdom); Bryce, Martin R. [Department of Chemistry, Durham University, Durham DH1 3LE (United Kingdom); Frampton, Harry; Chappell, David [BP Exploration Operating Company Limited, Chertsey Road, Sunbury on Thames, Middlesex TW16 7BP (United Kingdom)

    2014-02-07

    To identify families of stable planar anchor groups for use in single molecule electronics, we report detailed results for the binding energies of two families of anthracene and pyrene derivatives adsorbed onto graphene. We find that all the selected derivatives functionalized with either electron donating or electron accepting substituents bind more strongly to graphene than the parent non-functionalized anthracene or pyrene. The binding energy is sensitive to the detailed atomic alignment of substituent groups over the graphene substrate leading to larger than expected binding energies for –OH and –CN derivatives. Furthermore, the ordering of the binding energies within the anthracene and pyrene series does not simply follow the electron affinities of the substituents. Energy barriers to rotation or displacement on the graphene surface are much lower than binding energies for adsorption and therefore at room temperature, although the molecules are bound to the graphene, they are almost free to move along the graphene surface. Binding energies can be increased by incorporating electrically inert side chains and are sensitive to the conformation of such chains.

  6. A study of planar anchor groups for graphene-based single-molecule electronics

    Science.gov (United States)

    Bailey, Steven; Visontai, David; Lambert, Colin J.; Bryce, Martin R.; Frampton, Harry; Chappell, David

    2014-02-01

    To identify families of stable planar anchor groups for use in single molecule electronics, we report detailed results for the binding energies of two families of anthracene and pyrene derivatives adsorbed onto graphene. We find that all the selected derivatives functionalized with either electron donating or electron accepting substituents bind more strongly to graphene than the parent non-functionalized anthracene or pyrene. The binding energy is sensitive to the detailed atomic alignment of substituent groups over the graphene substrate leading to larger than expected binding energies for -OH and -CN derivatives. Furthermore, the ordering of the binding energies within the anthracene and pyrene series does not simply follow the electron affinities of the substituents. Energy barriers to rotation or displacement on the graphene surface are much lower than binding energies for adsorption and therefore at room temperature, although the molecules are bound to the graphene, they are almost free to move along the graphene surface. Binding energies can be increased by incorporating electrically inert side chains and are sensitive to the conformation of such chains.

  7. A study of planar anchor groups for graphene-based single-molecule electronics

    International Nuclear Information System (INIS)

    Bailey, Steven; Visontai, David; Lambert, Colin J.; Bryce, Martin R.; Frampton, Harry; Chappell, David

    2014-01-01

    To identify families of stable planar anchor groups for use in single molecule electronics, we report detailed results for the binding energies of two families of anthracene and pyrene derivatives adsorbed onto graphene. We find that all the selected derivatives functionalized with either electron donating or electron accepting substituents bind more strongly to graphene than the parent non-functionalized anthracene or pyrene. The binding energy is sensitive to the detailed atomic alignment of substituent groups over the graphene substrate leading to larger than expected binding energies for –OH and –CN derivatives. Furthermore, the ordering of the binding energies within the anthracene and pyrene series does not simply follow the electron affinities of the substituents. Energy barriers to rotation or displacement on the graphene surface are much lower than binding energies for adsorption and therefore at room temperature, although the molecules are bound to the graphene, they are almost free to move along the graphene surface. Binding energies can be increased by incorporating electrically inert side chains and are sensitive to the conformation of such chains

  8. GPIHBP1 and Plasma Triglyceride Metabolism

    DEFF Research Database (Denmark)

    Fong, Loren G; Young, Stephen G; Beigneux, Anne P

    2016-01-01

    GPIHBP1, a GPI-anchored protein in capillary endothelial cells, is crucial for the lipolytic processing of triglyceride-rich lipoproteins (TRLs). GPIHBP1 shuttles lipoprotein lipase (LPL) to its site of action in the capillary lumen and is essential for the margination of TRLs along capillaries -...

  9. Employees’ work engagement and job commitment: The moderating role of career anchors

    Directory of Open Access Journals (Sweden)

    Melinde Coetzee

    2014-08-01

    Research purpose: The objective of the present study was to assess whether individuals’career anchors (measured by the career orientations inventory significantly moderate therelationship between their work engagement (measured by the Utrecht work engagementscale and job commitment (measured by the organisation-related commitment scale. Motivation for the study: Although the literature review suggests that people’s workengagement and job commitment may be influenced by their career anchors, there seems to bea paucity of research examining the interaction effects between these three variables. Research approach, design and method: A cross-sectional quantitative survey approach wasused. A non-probability purposive sample of adults (N = 318 employed in a human resourcecapacity in the South African service industry participated in the study. Stepwise hierarchicalmoderated regression analysis was performed to achieve the objective of the study. Main findings: The results showed that the work engagement-job commitment relationshipwas generally stronger for high career anchor preferences than for low career anchorpreferences.Practical/managerial implications: The results of the study can be useful when human resourceinterventions for enhancing employees’ engagement and commitment are developed. Contribution: The results of the study add new insights to the career literature by showing thatpeople’s career self-concepts (as reflected by their career anchors are important to consider inenhancing their work engagement and job commitment.

  10. End-anchored polymers in good solvents from the single chain limit to high anchoring densities.

    Science.gov (United States)

    Whitmore, Mark D; Grest, Gary S; Douglas, Jack F; Kent, Michael S; Suo, Tongchuan

    2016-11-07

    An increasing number of applications utilize grafted polymer layers to alter the interfacial properties of solid substrates, motivating refinement in our theoretical understanding of such layers. To assess existing theoretical models of them, we have investigated end-anchored polymer layers over a wide range of grafting densities, σ, ranging from a single chain to high anchoring density limits, chain lengths ranging over two orders of magnitude, for very good and marginally good solvent conditions. We compare Monte Carlo and molecular dynamics simulations, numerical self-consistent field calculations, and experimental measurements of the average layer thickness, h, with renormalization group theory, the Alexander-de Gennes mushroom theory, and the classical brush theory. Our simulations clearly indicate that appreciable inter-chain interactions exist at all simulated areal anchoring densities so that there is no mushroom regime in which the layer thickness is independent of σ. Moreover, we find that there is no high coverage regime in which h follows the predicted scaling, h ∼ Nσ 1/3 , for classical polymer brushes either. Given that no completely adequate analytic theory seems to exist that spans wide ranges of N and σ, we applied scaling arguments for h as a function of a suitably defined reduced anchoring density, defined in terms of the solution radius of gyration of the polymer chains and N. We find that such a scaling approach enables a smooth, unified description of h in very good solvents over the full range of anchoring density and chain lengths, although this type of data reduction does not apply to marginal solvent quality conditions.

  11. Studies on the mechanical behavior of rock anchors. ; Results of in-situ pull-out tests. Rock anchor no rikigaku kyodo ni kansuru kenkyu. ; Gen prime ichi shiken ni okeru anchor no kyodo

    Energy Technology Data Exchange (ETDEWEB)

    Arimoto, K.; Ebisu, S.; Nakagawa, M.; Usui, M.; Someya, T.; Machida, N. (Okumura Corp., Tokyo (Japan))

    1991-10-31

    The rock anchor method is planned to apply to some permanent structures but since this method was developed for temporary structures, the clarification of the transferring mechanism of force from an anchor to a rockmass, the fracture mechanism and the development of the dynamic model have not been established. This paper arranged the data obtained by a full-scale, in-situ pulling out test of a rock anchor as the first step to understand the dynamic behavior and analyzed by paying attetion to the modulus of deformation of the rockmass where the anchor was embedded to elucidate the affecting degree of rockmass modulus of deformation, the embedded length and the tendon diameter on the dynamic behavior of the anchor. The rock anchor behavior could be expressed accurately by applying a theoretical solution derived by the balancing condition of forces at the boundary face. Especially, when the rockmass is uniform and the fracture occurrs at the interface between the tendon and grout, this approach can express the fracture with the accuracy similar to that made by the finite element method. 6 refs., 11 figs.,1 tab.

  12. Containment liner plate anchors and steel embedments test results

    International Nuclear Information System (INIS)

    Chang-Lo, P.L.; Johnson, T.E.; Pfeifer, B.W.

    1977-01-01

    This paper summarizes test data on shear load and deformation capabilities for liner plate line anchors and structural steel embedments in reinforced and prestressed concrete nuclear containments. Reinforced and prestressed nuclear containments designed and constructed in the United States are lined with a minimum of 0.64 cm steel plate. The liner plates are anchored by the use of either studs or structural members (line anchors) which usually run in the vertical direction. This paper will only address line anchors. Static load versus displacement test data is necessary to assure that the design is adequate for the maximum loads. The test program for the liner anchors had the following major objectives: determine load versus displacement data for a variety of anchors considering structural tees and small beams with different weld configurations, from the preceding tests, determine which anchors would lead to an economical and extremely safe design and test these anchors for cyclic loads resulting from thermal fluctuations. Various concrete embeds in the containment and other structures are subjected to loads such as pipe rupture which results in shear. Since many of the loads are transient by nature, it is necessary to know the load-displacement relationship so that the energy absorption can be determined. The test program for the embeds had the following objectives: determine load-displacement relationship for various size anchors from 6.5 cm 2 to 26 cm 2 with maximum capacities of approximately 650 kN; determine the effect of various anchor width-to-thickness ratios for the same shear area

  13. Anomalous carrier life-time relaxation mediated by head group interaction in surface anchored MnSe quantum dots conjugated with albumin proteins

    Energy Technology Data Exchange (ETDEWEB)

    Sarma, Runjun; Mohanta, Dambarudhar, E-mail: best@tezu.ernet.in

    2017-02-01

    We report on the radiative emission decay dynamics of a less known, γ-phase manganese selenide quantum dot system (MnSe QDs) subjected to bio-functionalization. A short-ligand thioglycolic acid (TGA), and a long-chain sodium dodecyl sulfate (SDS) surfactants were used as surface anchors prior bioconjugation with albumin proteins (BSA). Time resolved photoluminescence (TR-PL) spectra of the QDs have revealed bi-exponential decay trends with the fast (τ{sub 1}) and slow (τ{sub 2}) decay parameters assigned to the core state recombination and surface trapped excitons; respectively. The average lifetime (τ{sub avg}) was found to get shortened from a value of ∼0.87 ns–0.72 ns in unconjugated and BSA conjugated MnSe-TGA QDs; respectively. Conversely, MnSe-SDS QDs with BSA conjugation exhibited nearly four-fold enhancement of τ{sub avg} with respect to its unconjugated counterpart. Moreover, a considerable amount of Förster resonance energy transfer (FRET) was found to occur from the TGA coated MnSe QDs to BSA and with an ensuing efficiency of ∼61%. The origin of anomalous carrier life-time relaxation features has also been encountered through a simplified model as regards head group interaction experienced by the MnSe QDs with different surfactant types. Exploiting luminescence decay characteristics of a magneto-fluorescent candidate could find immense scope in diverse biological applications including assays, labeling and imaging. - Highlights: • Surface anchored manganese selenide quantum dots (MnSe QDs) have been synthesized via a physico-chemical reduction route. • Time resolved luminescence spectra of the QDs have displayed bi-exponential decay trend. • Thioglycolic acid (TGA) coated QDs exhibited shorter lifetime as compared to sodium dodecyl sulfo-succinate (SDS) coated ones. • Upon BSA conjugation, the average life time is four-fold enhanced in MnSe-SDS QDs. • An efficient FRET process has been revealed in BSA conjugated TGA coated MnSe QDs.

  14. Editorial Commentary: All-Suture Anchors, Foam Blocks, and Biomechanical Testing.

    Science.gov (United States)

    Brand, Jefferson C

    2017-06-01

    Barber's biomechanical work is well known to Arthroscopy's readers as thorough, comprehensive, and inclusive of new designs as they become available. In "All-Suture Anchors: Biomechanical Analysis of Pullout Strength, Displacement, and Failure Mode," the latest iteration, Barber and Herbert test all-suture anchors in both porcine femurs and biphasic foam. While we await in vivo clinical trials that compare all-suture anchors to currently used anchors, Barber and Herbert have provided data to inform anchor choice, and using their biomechanical data at time zero from all-suture anchor trials in an animal model, we can determine the anchors' feasibility for human clinical investigations. Copyright © 2017 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.

  15. Spectroscopic and first principles investigation on 4-[(4-pyridinylmethylene)amino]-benzoic acid bearing pyridyl and carboxyl anchoring groups

    Science.gov (United States)

    Zhang, Lei; Wang, Qiaoyi

    2018-03-01

    We report a combined experimental and computational investigation on the structure and photophysics of 4-[(4-pyridinylmethylene)amino]-benzoic acid, a functional molecule bearing two anchoring groups for attachment onto a TiO2 surface and perovskite surface, for potential solar cell application. This molecule possesses interesting adsorption properties in perovskite solar cell because the pyridyl group serves as the Lewis base and targets Lewis acidic sites in the perovskite surface, while the carboxyl group targets TiO2 surface, improving the coupling between the perovskite surface and the TiO2 surface. The electronic structures of the molecule and its photochemistry are revealed by the UV-vis absorption spectra and the fluorescence spectra under visible light irradiation, which are combined with density functional theory (DFT) and time-dependent density functional theory (TDDFT) analysis. Considering the bi-anchoring groups and the conjugated π system embedded in the molecule, we anticipate it can molecular engineer the TiO2/perovskite interface in perovskite solar cell.

  16. Self-Assembled Monolayers on Gold of β-Cyclodextrin Adsorbates with Different Anchoring Groups

    NARCIS (Netherlands)

    Méndez Ardoy, Alejandro; Steentjes, Tom; Kudernac, Tibor; Huskens, Jurriaan

    2014-01-01

    We designed multivalent β-cyclodextrin-based adsorbates bearing different anchoring groups aiming to yield stable monolayers with improved packing and close contact of the cavity to the gold surface. Toward this end the primary rim of the β-cyclodextrin was decorated with several functional groups,

  17. Relation between anchorings of liquid crystals and conformation changes in aligning agents by the Langmuir-Blodgett film technique investigation

    International Nuclear Information System (INIS)

    Zhu, Y.; Lu, Z.; Wei, Y.

    1995-01-01

    The anchoring direction of liquid crystals on a solid substrate surface depends upon many parameters characterizing the liquid-crystal--substrate interface, a variation of which may change this anchoring direction leading to the so-called anchoring transition. Here, based on the Langmuir-Blodgett film technique, we present two model systems to study the relation between anchoring directions and the conformation changes in aligning agents. A double-armed crown ether liquid crystal and a side chain polymer liquid crystal at an air-water interface both show phase transitions, accompanied by conformation changes. However, when the monolayers in different phases were transferred onto solid substrates to orient liquid crystals, we found that for the crown ether material the conformation change can alter the anchoring of liquid crystals between homeotropic and homogeneous alignments, while for the polymer liquid crystal, despite the conformation changes, the liquid crystals can only be aligned homeotropically. The involved mechanisms were briefly discussed in terms of the Landau-type phenomenological theory

  18. Nanofabricated racks of aligned and anchored DNA substrates for single-molecule imaging.

    Science.gov (United States)

    Gorman, Jason; Fazio, Teresa; Wang, Feng; Wind, Shalom; Greene, Eric C

    2010-01-19

    Single-molecule studies of biological macromolecules can benefit from new experimental platforms that facilitate experimental design and data acquisition. Here we develop new strategies to construct curtains of DNA in which the molecules are aligned with respect to one another and maintained in an extended configuration by anchoring both ends of the DNA to the surface of a microfluidic sample chamber that is otherwise coated with an inert lipid bilayer. This "double-tethered" DNA substrate configuration is established through the use of nanofabricated rack patterns comprised of two distinct functional elements: linear barriers to lipid diffusion that align DNA molecules anchored by one end to the bilayer and antibody-coated pentagons that provide immobile anchor points for the opposite ends of the DNA. These devices enable the alignment and anchoring of thousands of individual DNA molecules, which can then be visualized using total internal reflection fluorescence microscopy under conditions that do not require continuous application of buffer flow to stretch the DNA. This unique strategy offers the potential for studying protein-DNA interactions on large DNA substrates without compromising measurements through application of hydrodynamic force. We provide a proof-of-principle demonstration that double-tethered DNA curtains made with nanofabricated rack patterns can be used in a one-dimensional diffusion assay that monitors the motion of quantum dot-tagged proteins along DNA.

  19. Outcomes of the modified Brostrom procedure using suture anchors for chronic lateral ankle instability--a prospective, randomized comparison between single and double suture anchors.

    Science.gov (United States)

    Cho, Byung-Ki; Kim, Yong-Min; Kim, Dong-Soo; Choi, Eui-Sung; Shon, Hyun-Chul; Park, Kyoung-Jin

    2013-01-01

    The present prospective, randomized study was conducted to compare the clinical outcomes of the modified Brostrom procedure using single and double suture anchors for chronic lateral ankle instability. A total of 50 patients were followed up for more than 2 years after undergoing the modified Brostrom procedure. Of the 50 procedures, 25 each were performed using single and double suture anchors by 1 surgeon. The Karlsson scale had improved significantly to 89.8 points and 90.6 points in the single and double anchor groups, respectively. Using the Sefton grading system, 23 cases (92%) in the single anchor group and 22 (88%) in the double anchor group achieved satisfactory results. The talar tilt angle and anterior talar translation on stress radiographs using the Telos device had improved significantly to an average of 5.7° and 4.6 mm in the single anchor group and 4.5° and 4.3 mm in the double anchor group, respectively. The double anchor technique was superior with respect to the postoperative talar tilt. The single and double suture anchor techniques produced similar clinical and functional outcomes, with the exception of talar tilt as a reference of mechanical stability. The modified Brostrom procedure using both single and double suture anchors appears to be an effective treatment method for chronic lateral ankle instability. Copyright © 2013 American College of Foot and Ankle Surgeons. Published by Elsevier Inc. All rights reserved.

  20. Brittle Culm1, a COBRA-Like Protein, Functions in Cellulose Assembly through Binding Cellulose Microfibrils

    Science.gov (United States)

    Zhang, Baocai; Liu, Xiangling; Yan, Meixian; Zhang, Lanjun; Shi, Yanyun; Zhang, Mu; Qian, Qian; Li, Jiayang; Zhou, Yihua

    2013-01-01

    Cellulose represents the most abundant biopolymer in nature and has great economic importance. Cellulose chains pack laterally into crystalline forms, stacking into a complicated crystallographic structure. However, the mechanism of cellulose crystallization is poorly understood. Here, via functional characterization, we report that Brittle Culm1 (BC1), a COBRA-like protein in rice, modifies cellulose crystallinity. BC1 was demonstrated to be a glycosylphosphatidylinositol (GPI) anchored protein and can be released into cell walls by removal of the GPI anchor. BC1 possesses a carbohydrate-binding module (CBM) at its N-terminus. In vitro binding assays showed that this CBM interacts specifically with crystalline cellulose, and several aromatic residues in this domain are essential for binding. It was further demonstrated that cell wall-localized BC1 via the CBM and GPI anchor is one functional form of BC1. X-ray diffraction (XRD) assays revealed that mutations in BC1 and knockdown of BC1 expression decrease the crystallite width of cellulose; overexpression of BC1 and the CBM-mutated BC1s caused varied crystallinity with results that were consistent with the in vitro binding assay. Moreover, interaction between the CBM and cellulose microfibrils was largely repressed when the cell wall residues were pre-stained with two cellulose dyes. Treating wild-type and bc1 seedlings with the dyes resulted in insensitive root growth responses in bc1 plants. Combined with the evidence that BC1 and three secondary wall cellulose synthases (CESAs) function in different steps of cellulose production as revealed by genetic analysis, we conclude that BC1 modulates cellulose assembly by interacting with cellulose and affecting microfibril crystallinity. PMID:23990797

  1. Brittle Culm1, a COBRA-like protein, functions in cellulose assembly through binding cellulose microfibrils.

    Directory of Open Access Journals (Sweden)

    Lifeng Liu

    Full Text Available Cellulose represents the most abundant biopolymer in nature and has great economic importance. Cellulose chains pack laterally into crystalline forms, stacking into a complicated crystallographic structure. However, the mechanism of cellulose crystallization is poorly understood. Here, via functional characterization, we report that Brittle Culm1 (BC1, a COBRA-like protein in rice, modifies cellulose crystallinity. BC1 was demonstrated to be a glycosylphosphatidylinositol (GPI anchored protein and can be released into cell walls by removal of the GPI anchor. BC1 possesses a carbohydrate-binding module (CBM at its N-terminus. In vitro binding assays showed that this CBM interacts specifically with crystalline cellulose, and several aromatic residues in this domain are essential for binding. It was further demonstrated that cell wall-localized BC1 via the CBM and GPI anchor is one functional form of BC1. X-ray diffraction (XRD assays revealed that mutations in BC1 and knockdown of BC1 expression decrease the crystallite width of cellulose; overexpression of BC1 and the CBM-mutated BC1s caused varied crystallinity with results that were consistent with the in vitro binding assay. Moreover, interaction between the CBM and cellulose microfibrils was largely repressed when the cell wall residues were pre-stained with two cellulose dyes. Treating wild-type and bc1 seedlings with the dyes resulted in insensitive root growth responses in bc1 plants. Combined with the evidence that BC1 and three secondary wall cellulose synthases (CESAs function in different steps of cellulose production as revealed by genetic analysis, we conclude that BC1 modulates cellulose assembly by interacting with cellulose and affecting microfibril crystallinity.

  2. Brittle Culm1, a COBRA-like protein, functions in cellulose assembly through binding cellulose microfibrils.

    Science.gov (United States)

    Liu, Lifeng; Shang-Guan, Keke; Zhang, Baocai; Liu, Xiangling; Yan, Meixian; Zhang, Lanjun; Shi, Yanyun; Zhang, Mu; Qian, Qian; Li, Jiayang; Zhou, Yihua

    2013-01-01

    Cellulose represents the most abundant biopolymer in nature and has great economic importance. Cellulose chains pack laterally into crystalline forms, stacking into a complicated crystallographic structure. However, the mechanism of cellulose crystallization is poorly understood. Here, via functional characterization, we report that Brittle Culm1 (BC1), a COBRA-like protein in rice, modifies cellulose crystallinity. BC1 was demonstrated to be a glycosylphosphatidylinositol (GPI) anchored protein and can be released into cell walls by removal of the GPI anchor. BC1 possesses a carbohydrate-binding module (CBM) at its N-terminus. In vitro binding assays showed that this CBM interacts specifically with crystalline cellulose, and several aromatic residues in this domain are essential for binding. It was further demonstrated that cell wall-localized BC1 via the CBM and GPI anchor is one functional form of BC1. X-ray diffraction (XRD) assays revealed that mutations in BC1 and knockdown of BC1 expression decrease the crystallite width of cellulose; overexpression of BC1 and the CBM-mutated BC1s caused varied crystallinity with results that were consistent with the in vitro binding assay. Moreover, interaction between the CBM and cellulose microfibrils was largely repressed when the cell wall residues were pre-stained with two cellulose dyes. Treating wild-type and bc1 seedlings with the dyes resulted in insensitive root growth responses in bc1 plants. Combined with the evidence that BC1 and three secondary wall cellulose synthases (CESAs) function in different steps of cellulose production as revealed by genetic analysis, we conclude that BC1 modulates cellulose assembly by interacting with cellulose and affecting microfibril crystallinity.

  3. Understanding the low uptake of bone-anchored hearing aids: a review.

    Science.gov (United States)

    Powell, R; Wearden, A; Pardesi, S M; Green, K

    2017-03-01

    Bone-anchored hearing aids improve hearing for patients for whom conventional behind-the-ear aids are problematic. However, uptake of bone-anchored hearing aids is low and it is important to understand why this is the case. A narrative review was conducted. Studies examining why people accept or decline bone-anchored hearing aids and satisfaction levels of people with bone-anchored hearing aids were reviewed. Reasons for declining bone-anchored hearing aids included limited perceived benefits, concerns about surgery, aesthetic concerns and treatment cost. No studies providing in-depth analysis of the reasons for declining or accepting bone-anchored hearing aids were identified. Studies of patient satisfaction showed that most participants reported benefits with bone-anchored hearing aids. However, most studies used cross-sectional and/or retrospective designs and only included people with bone-anchored hearing aids. Important avenues for further research are in-depth qualitative research designed to fully understand the decision-making process for bone-anchored hearing aids and rigorous quantitative research comparing satisfaction of people who receive bone-anchored hearing aids with those who receive alternative (or no) treatments.

  4. Career anchors and learning plan (part one

    Directory of Open Access Journals (Sweden)

    Daniela Brečko

    2006-12-01

    Full Text Available The article is divided into three parts. The first part concentrates on how important career is for an individual, organization and society. The author establishes that understanding of career has changed dramatically and does not only refer to climbing up the career ladder, but also moving off or even down the career ladder. The notion of career, as a lifelong and professional path, encompasses all aspects of human personality and their roles acquired through one's life. On basis of vast and longitudinal research, where the author has studied career anchors of individuals, it is the objective of the author to find out on basis of what grounds do the individuals decide to take certain directions in their careers and how learning contributes to such decisions. As a source the author has used Shein's theory of career anchors. Part one describes in greater detail 8 different career anchors and introduces their main features with the findings of the research, which refer to the analysis of professions (work positions and established career anchors. The author thus verifies the hypothesis that career anchors do exist in our area.

  5. Self-tapping ability of carbon fibre reinforced polyetheretherketone suture anchors.

    Science.gov (United States)

    Feerick, Emer M; Wilson, Joanne; Jarman-Smith, Marcus; Ó'Brádaigh, Conchur M; McGarry, J Patrick

    2014-10-01

    An experimental and computational investigation of the self-tapping ability of carbon fibre reinforced polyetheretherketone (CFR-PEEK) has been conducted. Six CFR-PEEK suture anchor designs were investigated using PEEK-OPTIMA® Reinforced, a medical grade of CFR-PEEK. Experimental tests were conducted to investigate the maximum axial force and torque required for self-taping insertion of each anchor design. Additional experimental tests were conducted for some anchor designs using pilot holes. Computational simulations were conducted to determine the maximum stress in each anchor design at various stages of insertion. Simulations also were performed to investigate the effect of wall thickness in the anchor head. The maximum axial force required to insert a self-tapping CFR-PEEK suture anchor did not exceed 150 N for any anchor design. The maximum torque required to insert a self-tapping CFR-PEEK suture anchor did not exceed 0.8 Nm. Computational simulations reveal significant stress concentrations in the region of the anchor tip, demonstrating that a re-design of the tip geometry should be performed to avoid fracture during self-tapping, as observed in the experimental component of this study. This study demonstrates the ability of PEEK-OPTIMA Reinforced suture anchors to self-tap polyurethane foam bone analogue. This provides motivation to further investigate the self-tapping ability of CFR-PEEK suture anchors in animal/cadaveric bone. An optimised design for CFR-PEEK suture anchors offers the advantages of radiolucency, and mechanical properties similar to bone with the ability to self-tap. This may have positive implications for reducing surgery times and the associated costs with the procedure. © The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

  6. Electrical properties and mechanical stability of anchoring groups for single-molecule electronics

    Directory of Open Access Journals (Sweden)

    Riccardo Frisenda

    2015-07-01

    Full Text Available We report on an experimental investigation of transport through single molecules, trapped between two gold nano-electrodes fabricated with the mechanically controlled break junction (MCBJ technique. The four molecules studied share the same core structure, namely oligo(phenylene ethynylene (OPE3, while having different aurophilic anchoring groups: thiol (SAc, methyl sulfide (SMe, pyridyl (Py and amine (NH2. The focus of this paper is on the combined characterization of the electrical and mechanical properties determined by the anchoring groups. From conductance histograms we find that thiol anchored molecules provide the highest conductance; a single-level model fit to current–voltage characteristics suggests that SAc groups exhibit a higher electronic coupling to the electrodes, together with better level alignment than the other three groups. An analysis of the mechanical stability, recording the lifetime in a self-breaking method, shows that Py and SAc yield the most stable junctions while SMe form short-lived junctions. Density functional theory combined with non-equlibrium Green’s function calculations help in elucidating the experimental findings.

  7. Career anchors and values from different career management perspectives

    Directory of Open Access Journals (Sweden)

    Rodrigo Cunha da Silva

    2016-06-01

    Full Text Available Purpose – To analyze the relationships between career anchors and young Generation Y professionals’ values, from the career concept perspective. Design/methodology/approach – Research concerning the proposed objective was carried out through quantitative research involving 189 Business Administration majors from a Catholic university in São Paulo, Brazil. We used two instruments to identify the career anchors and values of respondents: Schein (1990 and Schwartz (1994, respectively. We used statistical techniques to explore the relationships between career anchors and values. Findings – Among the results, mention should be made to the statistical relationships found between analyzed career anchors and values. It is also important to stress that, although the Lifestyle career anchor was predominantly present in the conglomerate division, this anchor was the predominant characteristic in the differentiation of the smaller group of respondents, the new career group. The General Management Career Anchor, which presents a lower incidence, is the predominant characteristic of the larger group, referring to organizational careers. As well as the Lifestyle career anchor, the Hedonism value was predominant among respondents. Originality/value – The need to consider the following was found: Generation Y presents generational characteristics that drive people management to propose work structures that offer activities to generate learning, pleasure, self-fulfillment and conciliation between work and personal life.

  8. Test Score Equating Using Discrete Anchor Items versus Passage-Based Anchor Items: A Case Study Using "SAT"® Data. Research Report. ETS RR-14-14

    Science.gov (United States)

    Liu, Jinghua; Zu, Jiyun; Curley, Edward; Carey, Jill

    2014-01-01

    The purpose of this study is to investigate the impact of discrete anchor items versus passage-based anchor items on observed score equating using empirical data.This study compares an "SAT"® critical reading anchor that contains more discrete items proportionally, compared to the total tests to be equated, to another anchor that…

  9. On Moderator Detection in Anchoring Research: Implications of Ignoring Estimate Direction

    Directory of Open Access Journals (Sweden)

    Nathan N. Cheek

    2018-05-01

    Full Text Available Anchoring, whereby judgments assimilate to previously considered standards, is one of the most reliable effects in psychology. In the last decade, researchers have become increasingly interested in identifying moderators of anchoring effects. We argue that a drawback of traditional moderator analyses in the standard anchoring paradigm is that they ignore estimate direction—whether participants’ estimates are higher or lower than the anchor value. We suggest that failing to consider estimate direction can sometimes obscure moderation in anchoring tasks, and discuss three potential analytic solutions that take estimate direction into account. Understanding moderators of anchoring effects is essential for a basic understanding of anchoring and for applied research on reducing the influence of anchoring in real-world judgments. Considering estimate direction reduces the risk of failing to detect moderation.

  10. Biased calculations: Numeric anchors influence answers to math equations

    Directory of Open Access Journals (Sweden)

    Andrew R. Smith

    2011-02-01

    Full Text Available People must often perform calculations in order to produce a numeric estimate (e.g., a grocery-store shopper estimating the total price of his or her shopping cart contents. The current studies were designed to test whether estimates based on calculations are influenced by comparisons with irrelevant anchors. Previous research has demonstrated that estimates across a wide range of contexts assimilate toward anchors, but none has examined estimates based on calculations. In two studies, we had participants compare the answers to math problems with anchors. In both studies, participants' estimates assimilated toward the anchor values. This effect was moderated by time limit such that the anchoring effects were larger when the participants' ability to engage in calculations was limited by a restrictive time limit.

  11. DRAGON, a GPI-anchored membrane protein, inhibits BMP signaling in C2C12 myoblasts.

    Science.gov (United States)

    Kanomata, Kazuhiro; Kokabu, Shoichiro; Nojima, Junya; Fukuda, Toru; Katagiri, Takenobu

    2009-06-01

    Bone morphogenetic proteins (BMPs) induce osteoblastic differentiation of myoblasts via binding to cell surface receptors. Repulsive guidance molecules (RGMs) have been identified as BMP co-receptors. We report here that DRAGON/RGMb, a member of the RGM family, suppressed BMP signaling in C2C12 myoblasts via a novel mechanism. All RGMs were expressed in C2C12 cells that were differentiated into myocytes and osteoblastic cells, but RGMc was not detected in immature cells. In C2C12 cells, only DRAGON suppressed ALP and Id1 promoter activities induced by BMP-4 or by constitutively activated BMP type I receptors. This inhibition by DRAGON was dependent on the secretory form of the von Willbrand factor type D domain. DRAGON even suppressed BMP signaling induced by constitutively activated Smad1. Over-expression of neogenin did not alter the inhibitory capacity of DRAGON. Taken together, these findings indicate that DRAGON may be an inhibitor of BMP signaling in C2C12 myoblasts. We also suggest that a novel molecule(s) expressed on the cell membrane may mediate the signal transduction of DRAGON in order to suppress BMP signaling in C2C12 myoblasts.

  12. Binding constants of membrane-anchored receptors and ligands: A general theory corroborated by Monte Carlo simulations.

    Science.gov (United States)

    Xu, Guang-Kui; Hu, Jinglei; Lipowsky, Reinhard; Weikl, Thomas R

    2015-12-28

    Adhesion processes of biological membranes that enclose cells and cellular organelles are essential for immune responses, tissue formation, and signaling. These processes depend sensitively on the binding constant K2D of the membrane-anchored receptor and ligand proteins that mediate adhesion, which is difficult to measure in the "two-dimensional" (2D) membrane environment of the proteins. An important problem therefore is to relate K2D to the binding constant K3D of soluble variants of the receptors and ligands that lack the membrane anchors and are free to diffuse in three dimensions (3D). In this article, we present a general theory for the binding constants K2D and K3D of rather stiff proteins whose main degrees of freedom are translation and rotation, along membranes and around anchor points "in 2D," or unconstrained "in 3D." The theory generalizes previous results by describing how K2D depends both on the average separation and thermal nanoscale roughness of the apposing membranes, and on the length and anchoring flexibility of the receptors and ligands. Our theoretical results for the ratio K2D/K3D of the binding constants agree with detailed results from Monte Carlo simulations without any data fitting, which indicates that the theory captures the essential features of the "dimensionality reduction" due to membrane anchoring. In our Monte Carlo simulations, we consider a novel coarse-grained model of biomembrane adhesion in which the membranes are represented as discretized elastic surfaces, and the receptors and ligands as anchored molecules that diffuse continuously along the membranes and rotate at their anchor points.

  13. Technical Note: Drifting vs. anchored flux chambers for measuring greenhouse gas emissions from running waters

    Science.gov (United States)

    Lorke, A.; Bodmer, P.; Noss, C.; Alshboul, Z.; Koschorreck, M.; Somlai, C.; Bastviken, D.; Flury, S.; McGinnis, D. F.; Maeck, A.; Müller, D.; Premke, K.

    2015-09-01

    Stream networks were recently discovered as major but poorly constrained natural greenhouse gas (GHG) sources. A fundamental problem is that several measurement approaches have been used without cross comparisons. Flux chambers represent a potentially powerful methodological approach if robust and reliable ways to use chambers on running water can be defined. Here we compare the use of anchored and freely drifting chambers on various streams having different flow velocities. The study clearly shows that (1) drifting chambers have a very small impact on the water turbulence under the chamber and thus generate more reliable fluxes, (2) anchored chambers enhance turbulence under the chambers and thus elevate fluxes, (3) the bias of the anchored chambers greatly depends on chamber design and sampling conditions, and (4) there is a promising method to reduce the bias from anchored chambers by using a flexible plastic foil seal to the water surface rather than having rigid chamber walls penetrating into the water. Altogether, these results provide novel guidance on how to apply flux chambers in running water, which will have important consequences for measurements to constrain the global GHG balances.

  14. Technical note: drifting versus anchored flux chambers for measuring greenhouse gas emissions from running waters

    Science.gov (United States)

    Lorke, A.; Bodmer, P.; Noss, C.; Alshboul, Z.; Koschorreck, M.; Somlai-Haase, C.; Bastviken, D.; Flury, S.; McGinnis, D. F.; Maeck, A.; Müller, D.; Premke, K.

    2015-12-01

    Stream networks have recently been discovered to be major but poorly constrained natural greenhouse gas (GHG) sources. A fundamental problem is that several measurement approaches have been used without cross-comparisons. Flux chambers represent a potentially powerful methodological approach if robust and reliable ways to use chambers on running water can be defined. Here we compare the use of anchored and freely drifting chambers on various streams with different flow velocities. The study clearly shows that (1) anchored chambers enhance turbulence under the chambers and thus elevate fluxes, (2) drifting chambers have a very small impact on the water turbulence under the chamber and thus generate more reliable fluxes, (3) the bias of the anchored chambers greatly depends on chamber design and sampling conditions, and (4) there is a promising method to reduce the bias from anchored chambers by using a flexible plastic foil collar to seal the chambers to the water surface, rather than having rigid chamber walls penetrating into the water. Altogether, these results provide novel guidance on how to apply flux chambers in running water, which will have important consequences for measurements to constrain the global GHG balances.

  15. [Construction of Lactobacillus rhamnosus GG particles surface display system].

    Science.gov (United States)

    Su, Runyu; Nie, Boyao; Yuan, Shengling; Tao, Haoxia; Liu, Chunjie; Yang, Bailiang; Wang, Yanchun

    2017-01-25

    To describe a novel particles surface display system which is consisted of gram-positive enhancer matrix (GEM) particles and anchor proteins for bacteria-like particles vaccines, we treated Lactobacillus rhamnosus GG bacteria with 10% heated-TCA for preparing GEM particles, and then identified the harvested GEM particles by electron microscopy, RT-PCR and SDS-PAGE. Meanwhile, Escherichia coli was induced to express hybrid proteins PA3-EGFP and P60-EGFP, and GEM particles were incubated with them. Then binding of anchor proteins were determined by Western blotting, transmission electron microscopy, fluorescence microscopy and spectrofluorometry. GEM particles preserved original size and shape, and proteins and DNA contents of GEM particles were released substantially. The two anchor proteins both had efficiently immobilized on the surface of GEM. GEM particles that were bounded by anchor proteins were brushy. The fluorescence of GEM particles anchoring PA3 was slightly brighter than P60, but the difference was not significant (P>0.05). GEM particles prepared from L. rhamnosus GG have a good binding efficiency with anchor proteins PA3-EGFP and P60-EGFP. Therefore, this novel foreign protein surface display system could be used for bacteria-like particle vaccines.

  16. Laser-Modified Surface Enhances Osseointegration and Biomechanical Anchorage of Commercially Pure Titanium Implants for Bone-Anchored Hearing Systems

    Science.gov (United States)

    Omar, Omar; Simonsson, Hanna; Palmquist, Anders; Thomsen, Peter

    2016-01-01

    Osseointegrated implants inserted in the temporal bone are a vital component of bone-anchored hearing systems (BAHS). Despite low implant failure levels, early loading protocols and simplified procedures necessitate the application of implants which promote bone formation, bone bonding and biomechanical stability. Here, screw-shaped, commercially pure titanium implants were selectively laser ablated within the thread valley using an Nd:YAG laser to produce a microtopography with a superimposed nanotexture and a thickened surface oxide layer. State-of-the-art machined implants served as controls. After eight weeks’ implantation in rabbit tibiae, resonance frequency analysis (RFA) values increased from insertion to retrieval for both implant types, while removal torque (RTQ) measurements showed 153% higher biomechanical anchorage of the laser-modified implants. Comparably high bone area (BA) and bone-implant contact (BIC) were recorded for both implant types but with distinctly different failure patterns following biomechanical testing. Fracture lines appeared within the bone ~30–50 μm from the laser-modified surface, while separation occurred at the bone-implant interface for the machined surface. Strong correlations were found between RTQ and BIC and between RFA at retrieval and BA. In the endosteal threads, where all the bone had formed de novo, the extracellular matrix composition, the mineralised bone area and osteocyte densities were comparable for the two types of implant. Using resin cast etching, osteocyte canaliculi were observed directly approaching the laser-modified implant surface. Transmission electron microscopy showed canaliculi in close proximity to the laser-modified surface, in addition to a highly ordered arrangement of collagen fibrils aligned parallel to the implant surface contour. It is concluded that the physico-chemical surface properties of laser-modified surfaces (thicker oxide, micro- and nanoscale texture) promote bone bonding

  17. Synthesis of highly dispersed Pt nanoclusters anchored graphene composites and their application for non-enzymatic glucose sensing

    International Nuclear Information System (INIS)

    Chang, Gang; Shu, Honghui; Huang, Qiwei; Oyama, Munetaka; Ji, Kai; Liu, Xiong; He, Yunbin

    2015-01-01

    Highlights: • PtNCs/graphene (PVP) composites were obtained by a clean and facile method. • The addition of graphene effectively promotes the catalytic performance of composites. • The highly dispersed PtNCs show superior electrocatalytic activity to glucose oxidation. • PtNCs/graphene (PVP) composites exhibit excellent stability and selectivity for nonenzymatic glucose detection. - Abstract: A facile and clean method by using ascorbic acid as mild reductant was developed to synthesize nanocomposites of graphene and platinum nanoclusters (PtNCs/graphene), in which Polyvinyl-Pyrrolidone (PVP) was added during the one-step reductive process so as to improve the dispersity of PtNCs on the graphene and decrease the size of PtNCs. By several characterization methods such as X-ray diffraction (XRD), field-emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy (XPS), we demonstrated that Pt nanoclusters have successfully anchored on the surface of graphene sheets with average diameter of 22 nm. It was found that with the assistant of PVP, Pt nanoclusters appeared with smaller particle size and narrower particle size distribution. Cyclic voltammetry and amperometric methods were used to evaluate the electro-catalytic activity of the synthesized nanocomposites toward the oxidation of glucose in neutral media (0.1 M PBS, pH 7.4). The PtNCs/graphene exhibited a rapid response time (about 3 s), a broad linear range (1 mM to 25 mM), good stability, and sensitivity estimated to be 1.21 μA cm −2 mM −1 (R = 0.995, 71.9 μA cm −2 mM −1 vs. geometric area). Additionally, the impact from the oxidation of interferences can be effectively limited by choosing the appropriate detection potential. These results indicated a great potential of PtNCs/graphene in fabricating novel non-enzymatic glucose sensors with high performance

  18. 76 FR 30301 - Commercial Acquisition; Anchor Tenancy

    Science.gov (United States)

    2011-05-25

    ... NATIONAL AERONAUTICS AND SPACE ADMINISTRATION 48 CFR Part 1812 RIN 2700-AD64 Commercial... consistent with NASA's authority under Section 401 of the Commercial Space Competitiveness Act (CSCA) of 1992. NASA may enter into multi-year anchor tenancy contracts for commercial space goods or services. Anchor...

  19. A comparison of lateral ankle ligament suture anchor strength.

    Science.gov (United States)

    Barber, F Alan; Herbert, Morley A; Crates, John M

    2013-06-01

    Lateral ankle ligament repairs increasingly use suture anchors instead of bone tunnels. Our purpose was to compare the biomechanical properties of a knotted and knotless suture anchor appropriate for a lateral ankle ligament reconstruction. In porcine distal fibulae, 10 samples of 2 different PEEK anchors were inserted. The attached sutures were cyclically loaded between 10N and 60N for 200 cycles. A destructive pull was performed and failure loads, cyclic displacement, stiffness, and failure mode recorded. PushLock 2.5 anchors failed before 200 cycles. PushLock 100 cycle displacement was less than Morphix 2.5 displacement (panchors completing 200 cycles was 86.5N (PushLock) and 252.1N (Morphix) (panchor breaking and suture breakage. The knotted Morphix demonstrated more displacement and greater failure strength than the knotless PushLock. The PushLock failed consistently with suture breaking. The Morphix anchor failed both by anchor breaking and by suture breaking. Copyright © 2012 European Foot and Ankle Society. Published by Elsevier Ltd. All rights reserved.

  20. Characterization of the aspects of osteoprogenitor cell interactions with physical tetracalcium phosphate anchorage on titanium implant surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Ko, Chia-Ling [Advanced Medical Devices and Composites Laboratory, Department of Fiber and Composite Materials, Feng Chia University, Taichung 40724, Taiwan (China); Dental Medical Devices and Materials Research Center, College of Dental Medicine, Kaohsiung Medical University, Kaohsiung 807, Taiwan (China); Chang, Ya-Yuan; Liou, Cian-Hua [Alliance Global Technology Co., Ltd., Kaohsiung Medical Device Special Zone in Southern Taiwan Science Park, Kaohsiung 82151, Taiwan (China); Chen, Wen-Cheng, E-mail: wencchen@fcu.edu.tw [Advanced Medical Devices and Composites Laboratory, Department of Fiber and Composite Materials, Feng Chia University, Taichung 40724, Taiwan (China)

    2015-04-01

    Well-designed implants are used not only to modify the geometry of the implant but also to change the chemical properties of its surfaces. The present study aims to assess the biofunctional effects of tetracalcium phosphate (TTCP) particles as a physical anchor on the implant surface derived through sandblasting. The characteristics of the surface, cell viability, and alkaline phosphatase (ALP) activity toward osteoprogenitor cells (D1) were obtained. D1 cells were cultured on a plain surface that underwent sandblasting and acid etching (SLA) (control SLA group) and on different SLA surfaces with different anchoring TTCP rates (new test groups, M and H). The mean anchoring rates were 57% (M) and 74% (H), and the anchored thickness was estimated to range from 12.6 μm to 18.3 μm. Compared with the control SLA surface on Ti substrate, the new test groups with different TTCP anchoring rates (M and H) failed to improve cell proliferation significantly but had a well-differentiated D1 cell phenotype that enhanced ALP expression in the early stage of cell cultures, specifically, at day 7. Results suggest that the SLA surface with anchored TTCP can accelerate progenitor bone cell mineralization. This study shows the potential clinical application of the constructed geometry in TTCP anchorage on Ti for dental implant surface modification. - Highlights: • TTCP (tetracalcium phosphate) as a physical anchorage on implant is characterized. • Theoretical values of anchored thickness and capping areas were estimated. • TTCP anchored by sandblasting can accelerate progenitor bone cell mineralization. • TTCP anchored on SLA (sandblasting and acid etching) surface is a promising method.

  1. Characterization of the aspects of osteoprogenitor cell interactions with physical tetracalcium phosphate anchorage on titanium implant surfaces

    International Nuclear Information System (INIS)

    Ko, Chia-Ling; Chang, Ya-Yuan; Liou, Cian-Hua; Chen, Wen-Cheng

    2015-01-01

    Well-designed implants are used not only to modify the geometry of the implant but also to change the chemical properties of its surfaces. The present study aims to assess the biofunctional effects of tetracalcium phosphate (TTCP) particles as a physical anchor on the implant surface derived through sandblasting. The characteristics of the surface, cell viability, and alkaline phosphatase (ALP) activity toward osteoprogenitor cells (D1) were obtained. D1 cells were cultured on a plain surface that underwent sandblasting and acid etching (SLA) (control SLA group) and on different SLA surfaces with different anchoring TTCP rates (new test groups, M and H). The mean anchoring rates were 57% (M) and 74% (H), and the anchored thickness was estimated to range from 12.6 μm to 18.3 μm. Compared with the control SLA surface on Ti substrate, the new test groups with different TTCP anchoring rates (M and H) failed to improve cell proliferation significantly but had a well-differentiated D1 cell phenotype that enhanced ALP expression in the early stage of cell cultures, specifically, at day 7. Results suggest that the SLA surface with anchored TTCP can accelerate progenitor bone cell mineralization. This study shows the potential clinical application of the constructed geometry in TTCP anchorage on Ti for dental implant surface modification. - Highlights: • TTCP (tetracalcium phosphate) as a physical anchorage on implant is characterized. • Theoretical values of anchored thickness and capping areas were estimated. • TTCP anchored by sandblasting can accelerate progenitor bone cell mineralization. • TTCP anchored on SLA (sandblasting and acid etching) surface is a promising method

  2. Human surfactant protein A2 gene mutations impair dimmer/trimer assembly leading to deficiency in protein sialylation and secretion.

    Directory of Open Access Journals (Sweden)

    Yi Song

    Full Text Available Surfactant protein A2 (SP-A2 plays an essential role in surfactant metabolism and lung host defense. SP-A2 mutations in the carbohydrate recognition domain have been related to familial pulmonary fibrosis and can lead to a recombinant protein secretion deficiency in vitro. In this study, we explored the molecular mechanism of protein secretion deficiency and the subsequent biological effects in CHO-K1 cells expressing both wild-type and several different mutant forms of SP-A2. We demonstrate that the SP-A2 G231V and F198S mutants impair the formation of dimmer/trimer SP-A2 which contributes to the protein secretion defect. A deficiency in sialylation, but not N-linked glycosylation, is critical to the observed dimmer/trimer impairment-induced secretion defect. Furthermore, both mutant forms accumulate in the ER and form NP-40-insoluble aggregates. In addition, the soluble mutant SP-A2 could be partially degraded through the proteasome pathway but not the lysosome or autophagy pathway. Intriguingly, 4-phenylbutyrate acid (4-PBA, a chemical chaperone, alleviates aggregate formation and partially rescued the protein secretion of SP-A2 mutants. In conclusion, SP-A2 G231V and F198S mutants impair the dimmer/trimer assembly, which contributes to the protein sialylation and secretion deficiency. The intracellular protein mutants could be partially degraded through the proteasome pathway and also formed aggregates. The treatment of the cells with 4-PBA resulted in reduced aggregation and rescued the secretion of mutant SP-A2.

  3. Link Anchors in Images: Is there Truth?

    NARCIS (Netherlands)

    Aly, Robin; McGuinness, Kevin; Kleppe, Martijn; Ordelman, Roeland J.F.; O'Connor, Noel; de Jong, Franciska M.G.

    2012-01-01

    While automatic linking in text collections is well understood, little is known about links in images. In this work, we investigate two aspects of anchors, the origin of a link, in images: 1) the requirements of users for such anchors, e.g. the things users would like more information on, and 2)

  4. Comprehensive Evaluation of Streptococcus sanguinis Cell Wall-Anchored Proteins in Early Infective Endocarditis▿ †

    OpenAIRE

    Turner, Lauren Senty; Kanamoto, Taisei; Unoki, Takeshi; Munro, Cindy L.; Wu, Hui; Kitten, Todd

    2009-01-01

    Streptococcus sanguinis is a member of the viridans group of streptococci and a leading cause of the life-threatening endovascular disease infective endocarditis. Initial contact with the cardiac infection site is likely mediated by S. sanguinis surface proteins. In an attempt to identify the proteins required for this crucial step in pathogenesis, we searched for surface-exposed, cell wall-anchored proteins encoded by S. sanguinis and then used a targeted signature-tagged mutagenesis (STM) a...

  5. The Effect of Mini and Midi Anchor Tests on Test Equating

    Science.gov (United States)

    Arikan, Çigdem Akin

    2018-01-01

    The main purpose of this study is to compare the test forms to the midi anchor test and the mini anchor test performance based on item response theory. The research was conducted with using simulated data which were generated based on Rasch model. In order to equate two test forms the anchor item nonequivalent groups (internal anchor test) was…

  6. Use of the ROC anchor in foot and ankle surgery. A retrospective study.

    Science.gov (United States)

    Kuwada, G T

    1999-05-01

    A retrospective study was conducted on the use of the ROC (Radial Osteo Compression) soft-tissue anchor in foot and ankle surgery. This article describes how the anchor is deployed, problematic aspects of using the anchor, and complications and success rates associated with the anchor in ankle stabilizations, posterior tibial tendon reconstruction, peroneus brevis tendon reconstruction after fracture of the base of the fifth metatarsal, and detachment and reattachment of the Achilles tendon. The ROC anchor consists of the anchor with nonabsorbable suture attached to the shaft, the deployment handle, and drill bits. The anchor and shaft are snapped into the deployment handle and inserted into the drill hole. Compression of the trigger deploys the anchor into the hole. The ROC anchor was found to be reliable, useful, and relatively easy to deploy, with outcomes similar to those of other soft-tissue anchors.

  7. Ultrastructure of the surface structures and haptor of Empleurosoma pyriforme (Ancyrocephalinae; Monopisthocotylea: Monogenea) from the gills of the teleost fish Therapon jarbua.

    Science.gov (United States)

    Ramasamy, P; Brennan, G P

    2000-02-01

    Infections with Empleurosoma pyriforme occur between successive secondary gill lamellae on both sides of the primary lamella of Therapon jarbua. The haptoral disc bears two pairs of anchors and a pair of connecting transverse bars. The attachment of the parasite to the host gill causes inflammation, erosion and degeneration of the gill epithelia. The ventral anchors consist of an inner core of irregularly arranged, electron-dense fibrils and a smooth outer core of electron-lucent fibrils, whereas the surface of the dorsal anchors is ridged. Both the dorsal and the ventral anchors may be extended or withdrawn. The connecting transverse bars consist of longitudinally arranged fibrils in an electron-dense matrix, whereas the tendons consist of fibrils, supported in a less electron-dense matrix, which interconnect the anchor erector-protractor muscles and the haptor muscles. Two types of perikarya are present. The less common type contain large multivesicular bodies and small electron-dense granules and are located only in the haptor region. The second and more common perikarya are present throughout the body surface. The cytoplasmic syncytium contains numerous electron-dense granules and electron-lucent vesicles. Beneath the syncytium, unicellular epidermal gland cells contain electron-dense granules. Neurones containing numerous electron-dense vesicles are present in the haptor region. Uniciliate presumed sensory receptors are distributed over the body surface. Groups of ciliated sensory structures are present in the forebody. Ciliated and non-ciliated presumed sensory receptors are present in the sleeve cavity of the anchors, on the haptor and in the vicinity of the oral apertures.

  8. Differential trypanosome surface coat regulation by a CCCH protein that co-associates with procyclin mRNA cis-elements.

    Directory of Open Access Journals (Sweden)

    Pegine Walrad

    2009-02-01

    Full Text Available The genome of Trypanosoma brucei is unusual in being regulated almost entirely at the post-transcriptional level. In terms of regulation, the best-studied genes are procyclins, which encode a family of major surface GPI-anchored glycoproteins (EP1, EP2, EP3, GPEET that show differential expression in the parasite's tsetse-fly vector. Although procyclin mRNA cis-regulatory sequences have provided the paradigm for post-transcriptional control in kinetoplastid parasites, trans-acting regulators of procyclin mRNAs are unidentified, despite intensive effort over 15 years. Here we identify the developmental regulator, TbZFP3, a CCCH-class predicted RNA binding protein, as an isoform-specific regulator of Procyclin surface coat expression in trypanosomes. We demonstrate (i that endogenous TbZFP3 shows sequence-specific co-precipitation of EP1 and GPEET, but not EP2 and EP3, procyclin mRNA isoforms, (ii that ectopic overexpression of TbZFP3 does not perturb the mRNA abundance of procyclin transcripts, but rather that (iii their protein expression is regulated in an isoform-specific manner, as evidenced by mass spectrometric analysis of the Procyclin expression signature in the transgenic cell lines. The TbZFP3 mRNA-protein complex (TbZFP3mRNP is identified as a trans-regulator of differential surface protein expression in trypanosomes. Moreover, its sequence-specific interactions with procyclin mRNAs are compatible with long-established predictions for Procyclin regulation. Combined with the known association of TbZFP3 with the translational apparatus, this study provides a long-sought missing link between surface protein cis-regulatory signals and the gene expression machinery in trypanosomes.

  9. Anchoring Proteins as Regulators of Signaling Pathways

    Science.gov (United States)

    Perino, Alessia; Ghigo, Alessandra; Scott, John D.; Hirsch, Emilio

    2012-01-01

    Spatial and temporal organization of signal transduction is coordinated through the segregation of signaling enzymes in selected cellular compartments. This highly evolved regulatory mechanism ensures the activation of selected enzymes only in the vicinity of their target proteins. In this context, cAMP-responsive triggering of protein kinase A is modulated by a family of scaffold proteins referred to as A-kinase anchoring proteins. A-kinase anchoring proteins form the core of multiprotein complexes and enable simultaneous but segregated cAMP signaling events to occur in defined cellular compartments. In this review we will focus on the description of A-kinase anchoring protein function in the regulation of cardiac physiopathology. PMID:22859670

  10. On the Robustness of Anchoring Effects in WTP and WTA Experiments

    OpenAIRE

    Drew Fudenberg; David K Levine; Zacharias Maniadis

    2010-01-01

    We reexamine the effects of the anchoring manipulation of Ariely, Loewenstein, and Prelec (2003) on the evaluation of common market goods and find very weak anchoring effects. We perform the same manipulation on the evaluation of binary lotteries, and find no anchoring effects at all. This suggests limits on the robustness of anchoring effects. (JEL C91, D12, D44)

  11. Involvement of detergent-insoluble complexes in the intracellular transport of intestinal brush border enzymes

    DEFF Research Database (Denmark)

    Danielsen, E M

    1995-01-01

    A number of transmembrane digestive enzymes of the porcine small intestinal brush border membrane were found to be partially Triton X-100-insoluble at 0 degree C and colocalized in gradient centrifugation experiments with the GPI-anchored alkaline phosphatase in low-density, detergent-insoluble c...... intracellularly. I therefore propose that, in the enterocyte, the brush border enzymes are targeted directly from the trans-Golgi network toward the apical cell surface......., and their insolubility increased to that of the steady-state level soon after they achieved their mature, complex glycosylation, i.e., after passage through the Golgi complex. Detergent-insoluble complexes isolated by density gradient centrifugation were highly enriched in brush border enzymes, and the enrichment...

  12. Career Paths, Images and Anchors: A Study with Brazilian Professionals

    Science.gov (United States)

    Kilimnik, Zelia Miranda; de Oliveira, Luiz Claudio Vieira; Sant'anna, Anderson De Souza; Barros, Delba Teixeira Rodrigues

    2011-01-01

    This article analyses career anchors changes associated to images and professionals trajectories. Its main question: Do anchors careers change through time? We conducted twelve interviews involving professionals from the Administration Area, applying Schein's Career Anchors Inventory (1993). We did the same two years later. In both of them, the…

  13. Stone anchors of India: Findings, classification and significance.

    Digital Repository Service at National Institute of Oceanography (India)

    Tripati, S.

    Various types of stone anchors have been observed during inshore and offshore explorations along the east and west coasts of India. The earliest stone anchors of India have been recorded from the Harappan sites (3rd millennium BC), but their shape...

  14. Decay accelerating factor (DAF) is anchored to membranes by a C-terminal glycolipid

    International Nuclear Information System (INIS)

    Medof, M.E.; Haas, R.; Walter, E.I.; Rosenberry, T.L.

    1986-01-01

    Purified 70 kDa membrane (m) DAF incorporates into cells when added in vitro. A 2 kDa smaller DAF form which functions extrinsically like C4bp but is unable to incorporate can be isolated from urine (u). Because of common deficits of mDAF and acetylcholinesterase (AChE) in erythrocytes (E) of patients with paroxysmal nocturnal hemoglobinuria (PNH), mDAF was analyzed for a O-terminal glycolipid membrane anchor similar to that in E AChE. Incubation of E with phosphatidylinositol-specific phospholipase C, an enzyme which cleaves a similar glycolipid anchor in trypanosome variant surface glycoproteins (mfVSGs), released 20% of the DAF antigen. The released DAF species resembled uDAF in size, extrinsic model of C4b2a decay, and lack of hydrophobicity. Reductive radiomethylation of mDAF with [ 14 C]HCHO and NaCNBH 3 revealed ethanolamine and glucosamine in proportions similar to those in the E AChE glycolipid anchor. Papain cleavage of radiomethylated mDAF released the labeled ethanolamine and glucosamine in small O-terminal fragments from the residual DAF that retained N-terminal Asp. Following labeling of the anchors of mDAF and E AChE with the lipophilic photoreagent 3-trifluoromethyl-3-(m-[ 125 I]iodophenyl)diazirine, cleavage at the glucosamine residue by deamination quantitatively released the label from both proteins. Biosynthetic labeling of Hela cells with [ 3 H]ethanolamine resulted in rapid 3 H incorporation into both 48 kDa proDAF and 70 kDa mDAF. These data indicate that mDAF is anchored by a glycolipid similar to that in E AChE, mfVSGs and Thy-1 antigen and raise the possibility that a defect in the assembly or attachment of this structure could account for the deficits of mDAF and E AChE in PNH

  15. Protein-Anchoring Therapy of Biglycan for Mdx Mouse Model of Duchenne Muscular Dystrophy.

    Science.gov (United States)

    Ito, Mikako; Ehara, Yuka; Li, Jin; Inada, Kosuke; Ohno, Kinji

    2017-05-01

    Duchenne muscular dystrophy (DMD) is a devastating muscle disease caused by loss-of-function mutations in DMD encoding dystrophin. No rational therapy is currently available. Utrophin is a paralog of dystrophin and is highly expressed at the neuromuscular junction. In mdx mice, utrophin is naturally upregulated throughout the muscle fibers, which mitigates muscular dystrophy. Protein-anchoring therapy was previously reported, in which a recombinant extracellular matrix (ECM) protein is delivered to and anchored to a specific target using its proprietary binding domains. Being prompted by a report that intramuscular and intraperitoneal injection of an ECM protein, biglycan, upregulates expression of utrophin and ameliorates muscle pathology in mdx mice, protein-anchoring therapy was applied to mdx mice. Recombinant adeno-associated virus serotype 8 (rAAV8) carrying hBGN encoding human biglycan was intravenously injected into 5-week-old mdx mice. The rAAV8-hBGN treatment improved motor deficits and decreased plasma creatine kinase activities. In muscle sections of treated mice, the number of central myonuclei and the distribution of myofiber sizes were improved. The treated mice increased gene expressions of utrophin and β1-syntrophin, as well as protein expressions of biglycan, utrophin, γ-sarcoglycan, dystrobrevin, and α1-syntrophin. The expression of hBGN in the skeletal muscle of the treated mice was 1.34-fold higher than that of the native mouse Bgn (mBgn). The low transduction efficiency and improved motor functions suggest that biglycan expressed in a small number of muscle fibers was likely to have been secreted and anchored to the cell surface throughout the whole muscular fibers. It is proposed that the protein-anchoring strategy can be applied not only to deficiency of an ECM protein as previously reported, but also to augmentation of a naturally induced ECM protein.

  16. Investigation of suction anchor pullout capacity under undrained conditions

    OpenAIRE

    Jarand, Pollestad

    2015-01-01

    Master's thesis in Offshore technology Floating units are dependent on reliable mooring systems to ensure safety during marine operations. Suction anchors have proved to be a technologically viable and cost-effective concept. They are capable of precision installation, re-use, and provide large resistive capacity. This thesis investigates load capacity and failure modes of suction anchors subjected to vertical, horizontal (lateral), and incline loading. Suction anchor design co...

  17. Formation of the food vacuole in Plasmodium falciparum: a potential role for the 19 kDa fragment of merozoite surface protein 1 (MSP1(19.

    Directory of Open Access Journals (Sweden)

    Anton R Dluzewski

    2008-08-01

    Full Text Available Plasmodium falciparum Merozoite Surface Protein 1 (MSP1 is synthesized during schizogony as a 195-kDa precursor that is processed into four fragments on the parasite surface. Following a second proteolytic cleavage during merozoite invasion of the red blood cell, most of the protein is shed from the surface except for the C-terminal 19-kDa fragment (MSP1(19, which is still attached to the merozoite via its GPI-anchor. We have examined the fate of MSP1(19 during the parasite's subsequent intracellular development using immunochemical analysis of metabolically labeled MSP1(19, fluorescence imaging, and immuno-electronmicroscopy. Our data show that MSP1(19 remains intact and persists to the end of the intracellular cycle. This protein is the first marker for the biogenesis of the food vacuole; it is rapidly endocytosed into small vacuoles in the ring stage, which coalesce to form the single food vacuole containing hemozoin, and persists into the discarded residual body. The food vacuole is marked by the presence of both MSP1(19 and the chloroquine resistance transporter (CRT as components of the vacuolar membrane. Newly synthesized MSP1 is excluded from the vacuole. This behavior indicates that MSP1(19 does not simply follow a classical lysosome-like clearance pathway, instead, it may play a significant role in the biogenesis and function of the food vacuole throughout the intra-erythrocytic phase.

  18. Treatment of ovarian cancer by targeting the tumor stem cell-associated carbohydrate antigen, Sialyl-Thomsen-nouveau.

    Science.gov (United States)

    Starbuck, Kristen; Al-Alem, Linah; Eavarone, David A; Hernandez, Silvia Fatima; Bellio, Chiara; Prendergast, Jillian M; Stein, Jenna; Dransfield, Daniel T; Zarrella, Bianca; Growdon, Whitfield B; Behrens, Jeff; Foster, Rosemary; Rueda, Bo R

    2018-05-01

    Recurrent ovarian cancer (OvCa) is thought to result in part from the inability to eliminate rare quiescent cancer stem cells (CSCs) that survive cytotoxic chemotherapy and drive tumor resurgence. The Sialyl-Thomsen-nouveau antigen (STn) is a carbohydrate moiety present on protein markers of CSCs in pancreatic, colon, and gastric malignancies. We have demonstrated that human OvCa cell lines contain varying levels of cells that independently express either STn or the ovarian CSC marker CD133. Here we determine co-expression of STn and CD133 in a subset of human OvCa cell lines. Analyses of colony and sphere forming capacity and of response to standard-of-care cytotoxic therapy suggest a subset of OvCa STn + cells display some CSC features. The effect of the anti-STn antibody-drug conjugates (ADCs) S3F-CL-MMAE and 2G12-2B2-CL-MMAE on OvCa cell viability in vitro and in vivo was also assessed. Treatment with S3F-CL-MMAE reduced the viability of two of three OvCa cell lines in vitro and exposure to either S3F-CL-MMAE or 2G12-2B2-CL-MMAE reduced OVCAR3-derived xenograft volume in vivo , depleting STn + tumor cells. In summary, STn + cells demonstrate some stem-like properties and specific therapeutic targeting of STn in ovarian tumors may be an effective clinical strategy to eliminate both STn + CSC and STn + non-CSC populations.

  19. Pyramidal anchor stone from Baga waters of Goa, west coast of India

    Digital Repository Service at National Institute of Oceanography (India)

    Tripati, S.

    . Pyramidal anchor stones have an apex hole which goes up to the round hole, however Goa anchor stone has no such perforation, but, instead has a rectangular cutting on the apex. The anchor stone is compared with Greek pyramidal anchor stones, and probably...

  20. Profiling and characterization of sialylated N-glycans by 2D-HPLC (HIAX/PGC) with online orbitrap MS/MS and offline MSn.

    Science.gov (United States)

    Hanneman, Andrew J S; Strand, James; Huang, Chi-Ting

    2014-02-01

    Glycosylation is a critical parameter used to evaluate protein quality and consistency. N-linked glycan profiling is fundamental to the support of biotherapeutic protein manufacturing from early stage process development through drug product commercialization. Sialylated glycans impact the serum half-life of receptor-Fc fusion proteins (RFPs), making their quality and consistency a concern during the production of fusion proteins. Here, we describe an analytical approach providing both quantitative profiling and in-depth mass spectrometry (MS)-based structural characterization of sialylated RFP N-glycans. Aiming to efficiently link routine comparability studies with detailed structural characterization, an integrated workflow was implemented employing fluorescence detection, online positive and negative ion tandem mass spectrometry (MS/MS), and offline static nanospray ionization-sequential mass spectrometry (NSI-MS(n)). For routine use, high-performance liquid chromatography profiling employs established fluorescence detection of 2-aminobenzoic acid derivatives (2AA) and hydrophilic interaction anion-exchange chromatography (HIAX) charge class separation. Further characterization of HIAX peak fractions is achieved by online (-) ion orbitrap MS/MS, offering the advantages of high mass accuracy and data-dependent MS/MS. As required, additional characterization uses porous graphitized carbon in the second chromatographic dimension to provide orthogonal (+) ion MS/MS spectra and buffer-free liquid chromatography peak eluants that are optimum for offline (+)/(-) NSI-MS(n) investigations to characterize low-abundance species and specific moieties including O-acetylation and sulfation. © 2013 Wiley Periodicals, Inc. and the American Pharmacists Association.

  1. The P9 pocket of HLA-DQ2 (non-Aspbeta57) has no particular preference for negatively charged anchor residues found in other type 1 diabetes-predisposing non-Aspbeta57 MHC class II molecules

    DEFF Research Database (Denmark)

    Quarsten, H; Paulsen, G; Johansen, B H

    1998-01-01

    Susceptibility and resistance to type 1 diabetes are associated with MHC class II alleles that carry non-Asp and Asp at residue 57 of their beta chain respectively. The effect of Asp or non-Aspbeta57 may relate to a differential ability of distinct class II molecules to bind specific immuno......-pathogenic peptides. Recent studies in man and mouse have revealed that some type 1 diabetes-predisposing non-Aspbeta57 class II molecules (i.e. DQ8, DR4Dw15 and I-Ag7) preferentially bind peptides with a negatively charged anchor residue at P9. It has been suggested that this is a common feature of type 1 diabetes......-predisposing class II molecules. The molecular explanation for such a phenomenon could be that class II beta chains with Aspbeta57 form a salt bridge between Aspbeta57 and a conserved Arg of the a chain, whereas in non-Aspbeta57 molecules the Arg is unopposed and free to interact with negatively charged P9 peptide...

  2. Anchor-Free Localization Method for Mobile Targets in Coal Mine Wireless Sensor Networks

    OpenAIRE

    Pei, Zhongmin; Deng, Zhidong; Xu, Shuo; Xu, Xiao

    2009-01-01

    Severe natural conditions and complex terrain make it difficult to apply precise localization in underground mines. In this paper, an anchor-free localization method for mobile targets is proposed based on non-metric multi-dimensional scaling (Multi-dimensional Scaling: MDS) and rank sequence. Firstly, a coal mine wireless sensor network is constructed in underground mines based on the ZigBee technology. Then a non-metric MDS algorithm is imported to estimate the reference nodes’ location. Fi...

  3. Peptide-Mediated Liposome Fusion: The Effect of Anchor Positioning

    Directory of Open Access Journals (Sweden)

    Niek S. A. Crone

    2018-01-01

    Full Text Available A minimal model system for membrane fusion, comprising two complementary peptides dubbed “E” and “K” joined to a cholesterol anchor via a polyethyleneglycol spacer, has previously been developed in our group. This system promotes the fusion of large unilamellar vesicles and facilitates liposome-cell fusion both in vitro and in vivo. Whilst several aspects of the system have previously been investigated to provide an insight as to how fusion is facilitated, anchor positioning has not yet been considered. In this study, the effects of placing the anchor at either the N-terminus or in the center of the peptide are investigated using a combination of circular dichroism spectroscopy, dynamic light scattering, and fluorescence assays. It was discovered that anchoring the “K” peptide in the center of the sequence had no effect on its structure, its ability to interact with membranes, or its ability to promote fusion, whereas anchoring the ‘E’ peptide in the middle of the sequence dramatically decreases fusion efficiency. We postulate that anchoring the ‘E’ peptide in the middle of the sequence disrupts its ability to form homodimers with peptides on the same membrane, leading to aggregation and content leakage.

  4. Testing methods of steel wi re ropes at the anchor

    Directory of Open Access Journals (Sweden)

    Stanislav Kropuch

    2012-12-01

    Full Text Available The present paper introduces an application of the acoustic andthermographic method in the defectoscopic testing of immobilesteel wire ropes at the most critical point, the anchor. Firstmeasurements and their results by these new defectoscopic methodsare shown. In defectoscopic tests at the anchor, the widelyused magnetic method gives unreliable results, and therefore presentsa problem for steel wire defectoscopy. Application of the two new methods in the steel wire defectoscopy at the anchor point will enableincreased safety measures at the anchor of steel wire ropes in bridge, roof, tower and aerial cable lift constructions.

  5. Retention in the Golgi apparatus and expression on the cell surface of Cfr/Esl-1/Glg-1/MG-160 are regulated by two distinct mechanisms.

    Science.gov (United States)

    Miyaoka, Yuichiro; Kato, Hidenori; Ebato, Kazuki; Saito, Shigeru; Miyata, Naoko; Imamura, Toru; Miyajima, Atsushi

    2011-11-15

    Cfr (cysteine-rich fibroblast growth factor receptor) is an Fgf (fibroblast growth factor)-binding protein without a tyrosine kinase. We have shown previously that Cfr is involved in Fgf18 signalling via Fgf receptor 3c. However, as Cfr is also known as Glg (Golgi apparatus protein)-1 or MG-160 and occurs in the Golgi apparatus, it remains unknown how the distribution of Cfr is regulated. In the present study, we performed a mutagenic analysis of Cfr to show that two distinct regions contribute to its distribution and stability. First, the C-terminal region retains Cfr in the Golgi apparatus. Secondly, the Cfr repeats in the extracellular juxtamembrane region destabilizes Cfr passed through the Golgi apparatus. This destabilization does not depend on the cleavage and secretion of the extracellular domain of Cfr. Furthermore, we found that Cfr with a GPI (glycosylphosphatidylinositol) anchor was predominantly expressed on the cell surface in Ba/F3 cells and affected Fgf18 signalling in a similar manner to the full-length Cfr, indicating that the interaction of Cfr with Fgfs on the cell surface is important for its function in Fgf signalling. These results suggest that the expression of Cfr in the Golgi apparatus and on the plasma membrane is finely tuned through two distinct mechanisms for exhibiting different functions.

  6. Synergism Analysis of Bedding Slope with Piles and Anchor Cable Support under Sine Wave Vehicle Load

    Directory of Open Access Journals (Sweden)

    Li Dan-Feng

    2016-01-01

    Full Text Available Slope instability under dynamic load is the technical difficulty in the engineering; the evaluation of slope stability under dynamic load and the control of dynamic load is particularly important. In this paper, taking the right side slope of K27+140 m~380 m typical section (K27 slope for short in Chongqing Fuling-Fengdu-Shizhu expresses highway as an example to calculate and analyze. The K27 slope is under sinusoidal vehicle load and supported by anchor cable and antislide pile to resist downslide strength; at the same time, the combined effect of them is studied. Three-dimensional finite element methodology (FEM is used to simulate the bedding slope with piles and anchor cable support; furthermore, the eigenvalue can be obtained. In order to reduce error of the elastic boundary conditions caused by the reflection effect of wavelengths, the combination of Lysmer surface viscous boundary and traditional ground support boundaries is utilized to analyze and calculate the time-histories during bedding slope under dynamic load. The dynamic response of pile anchor support to resist sliding force is obtained. The concept of the pile anchor supporting coordinate interval is put forward. Furthermore, it is verified that the pile anchor supporting coordinate interval can be used to evaluate the stability of the slope under dynamic load and provide a new method for the control of the dynamic load.

  7. Release of Glycoprotein (GP1 from the Tegumental Surface of Taenia solium by Phospholipase C from Clostridium perfringens Suggests a Novel Protein-Anchor to Membranes

    Directory of Open Access Journals (Sweden)

    Abraham Landa

    2010-01-01

    Full Text Available In order to explore how molecules are linked to the membrane surface in larval Taenia solium, whole cysticerci were incubated in the presence of phospholipase C from Clostridium perfringens (PLC. Released material was collected and analyzed in polyacrylamide gels with sodium dodecyl sulfate. Two major bands with apparent molecular weights of 180 and 43 kDa were observed. Western blot of released material and localization assays in cysticerci tissue sections using antibodies against five known surface glycoproteins of T. solium cysticerci indicated that only one, previously called GP1, was released. Similar localization studies using the lectins wheat-germ-agglutinin and Concanavalin A showed that N-acetyl-D-glucosamine, N-acetylneuraminic, sialic acid, αmethyl-D-mannoside, D-manose/glucose, and N-acetyl-D-glucosamine residues are abundantly present on the surface. On the other hand, we find that treatment with PLC releases molecules from the surface; they do not reveal Cross Reacting Determinant (CRD, suggesting a novel anchor to the membrane for the glycoprotein GP1.

  8. Glycoengineering of Chinese hamster ovary cells for enhanced erythropoietin N-glycan branching and sialylation

    DEFF Research Database (Denmark)

    Yin, Bojiao; Gao, Yuan; Chung, Cheng-yu

    2015-01-01

    Sialic acid, a terminal residue on complex N-glycans, and branching or antennarity can play key roles in both the biological activity and circulatory lifetime of recombinant glycoproteins of therapeutic interest. In order to examine the impact of glycosyltransferase expression on the N-glycosylat......Sialic acid, a terminal residue on complex N-glycans, and branching or antennarity can play key roles in both the biological activity and circulatory lifetime of recombinant glycoproteins of therapeutic interest. In order to examine the impact of glycosyltransferase expression on the N...... increased by 26%. The increase in sialic acid content was further verified by detailed profiling of the N-glycan structures using mass spectra (MS) analysis. In order to enhance antennarity/branching, UDP-N-acetylglucosamine: α-1,3-D-mannoside β1,4-N-acetylglucosaminyltransferase (GnTIV/Mgat4) and UDP...... a mean for enhancing both N-glycan branching complexity and sialylation with opportunities to generate tailored complex N-glycan structures on therapeutic glycoproteins in the future....

  9. Treatment response in Kawasaki disease is associated with sialylation levels of endogenous but not therapeutic intravenous immunoglobulin G.

    Science.gov (United States)

    Ogata, Shohei; Shimizu, Chisato; Franco, Alessandra; Touma, Ranim; Kanegaye, John T; Choudhury, Biswa P; Naidu, Natasha N; Kanda, Yutaka; Hoang, Long T; Hibberd, Martin L; Tremoulet, Adriana H; Varki, Ajit; Burns, Jane C

    2013-01-01

    Although intravenous immunoglobulin (IVIG) is highly effective in Kawasaki disease (KD), mechanisms are not understood and 10-20% of patients are treatment-resistant, manifesting a higher rate of coronary artery aneurysms. Murine models suggest that α2-6-linked sialic acid (α2-6Sia) content of IVIG is critical for suppressing inflammation. However, pro-inflammatory states also up-regulate endogenous levels of β-galactoside:α2-6 sialyltransferase-I (ST6Gal-I), the enzyme that catalyzes addition of α2-6Sias to N-glycans. We asked whether IVIG failures correlated with levels of α2-6Sia on infused IVIG or on the patient's own endogenous IgG. We quantified levels of α2-6Sia in infused IVIG and endogenous IgG from 10 IVIG-responsive and 10 resistant KD subjects using multiple approaches. Transcript levels of ST6GAL1, in patient whole blood and B cell lines were evaluated by RT-PCR. Plasma soluble (s)ST6Gal-I levels were measured by ELISA. There was no consistent difference in median sialylation levels of infused IVIG between groups. However, α2-6Sia levels in endogenous IgG, ST6GAL1 transcript levels, and ST6Gal-I protein in serum from IVIG-resistant KD subjects were lower than in responsive subjects at both pre-treatment and one-year time points (p treatment response in KD. Rather, lower sialylation of endogenous IgG and lower blood levels of ST6GALI mRNA and ST6Gal-I enzyme predict therapy resistance. These differences were stable over time, suggesting a genetic basis. Because IVIG-resistance increases risk of coronary artery aneurysms, our findings have important implications for the identification and treatment of such individuals.

  10. Assessing tether anchor labeling and usability in pickup trucks.

    Science.gov (United States)

    Klinich, Kathleen D; Manary, Miriam A; Malik, Laura A; Flannagan, Carol A; Jermakian, Jessica S

    2018-04-03

    The objective of this study was to investigate vehicle factors associated with child restraint tether use and misuse in pickup trucks and evaluate 4 labeling interventions designed to educate consumers on proper tether use. Volunteer testing was performed with 24 subjects and 4 different pickup trucks. Each subject performed 8 child restraint installations among the 4 pickups using 2 forward-facing restraints: a Britax Marathon G4.1 and an Evenflo Triumph. Vehicles were selected to represent 4 different implementations of tether anchors among pickups: plastic loop routers (Chevrolet Silverado), webbing routers (Ram), back wall anchors (Nissan Frontier), and webbing routers plus metal anchors (Toyota Tundra). Interventions included a diagram label, Quick Response (QR) Code linked to video instruction, coordinating text label, and contrasting text tag. Subjects used the child restraint tether in 93% of trials. However, tether use was completely correct in only 9% of trials. An installation was considered functional if the subject attached the tether to a tether anchor and had a tight installation (ignoring routing and head restraint position); 28% of subjects achieved a functional installation. The most common installation error was attaching the tether hook to the anchor/router directly behind the child restraint (near the top of the seatback) rather than placing the tether through the router and attaching it to the anchor in the adjacent seating position. The Nissan Frontier, with the anchor located on the back wall of the cab, had the highest rate of correct installations but also had the highest rate of attaching the tether to components other than the tether anchor (seat adjustor, child restraint storage hook, around head restraint). None of the labeling interventions had a significant effect on correct installation; not a single subject scanned the QR Code to access the video instruction. Subjects with the most successful installations spent extensive time

  11. Ultra-Fast Glyco-Coating of Non-Biological Surfaces

    Directory of Open Access Journals (Sweden)

    Eleanor Williams

    2016-01-01

    Full Text Available The ability to glycosylate surfaces has medical and diagnostic applications, but there is no technology currently recognized as being able to coat any surface without the need for prior chemical modification of the surface. Recently, a family of constructs called function-spacer-lipids (FSL has been used to glycosylate cells. Because it is known that lipid-based material can adsorb onto surfaces, we explored the potential and performance of cell-labelling FSL constructs to “glycosylate” non-biological surfaces. Using blood group A antigen as an indicator, the performance of a several variations of FSL constructs to modify a large variety of non-biological surfaces was evaluated. It was found the FSL constructs when optimised could in a few seconds glycosylate almost any non-biological surface including metals, glass, plastics, rubbers and other polymers. Although the FSL glycan coating was non-covalent, and therefore temporary, it was sufficiently robust with appropriate selection of spacer and surface that it could capture anti-glycan antibodies, immobilize cells (via antibody, and withstand incubation in serum and extensive buffer washing, making it suitable for diagnostic and research applications.

  12. Ru-bis(pyridine)pyrazolate (bpp)-Based Water-Oxidation Catalysts Anchored on TiO2: The Importance of the Nature and Position of the Anchoring Group.

    Science.gov (United States)

    Francàs, Laia; Richmond, Craig; Garrido-Barros, Pablo; Planas, Nora; Roeser, Stephan; Benet-Buchholz, Jordi; Escriche, Lluís; Sala, Xavier; Llobet, Antoni

    2016-04-04

    Three distinct functionalisation strategies have been applied to the in,in-[{Ru(II)(trpy)}2(μ-bpp)(H2O)2](3+) (trpy=2,2':6',2''-terpyridine, bpp=bis(pyridine)pyrazolate) water-oxidation catalyst framework to form new derivatives that can adsorb onto titania substrates. Modifications included the addition of sulfonate, carboxylate, and phosphonate anchoring groups to the terpyridine and bis(pyridyl)pyrazolate ligands. The complexes were characterised in solution by using 1D NMR, 2D NMR, and UV/Vis spectroscopic analysis and electrochemical techniques. The complexes were then anchored on TiO2-coated fluorinated tin oxide (FTO) films, and the reactivity of these new materials as water-oxidation catalysts was tested electrochemically through controlled-potential electrolysis (CPE) with oxygen evolution detected by headspace analysis with a Clark electrode. The results obtained highlight the importance of the catalyst orientation with respect to the titania surface in regard to its capacity to catalytically oxidize water to dioxygen. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  13. Archaeometallurgical investigation of the iron anchor from the Tantura F shipwreck

    Energy Technology Data Exchange (ETDEWEB)

    Aronson, A. [Faculty of Engineering, Tel Aviv University, Ramat Aviv 69978 (Israel); Ashkenazi, D., E-mail: dana@eng.tau.ac.il [Faculty of Engineering, Tel Aviv University, Ramat Aviv 69978 (Israel); Barkai, O.; Kahanov, Y. [Leon Recanati Institute for Maritime Studies, University of Haifa, Haifa 31905 (Israel)

    2013-04-15

    The Tantura F shipwreck was a coaster or a fishing vessel about 15.7 m long, discovered in the Dor/Tantura lagoon, Israel in 1995. It was dated to between the mid-7th and the end of the 8th centuries CE. Among the finds excavated were two T-shaped type iron anchors. Of the two anchors, one (anchor A) was thoroughly studied by archaeometallurgical methods in order to identify forge-welding lines, to determine the welding quality and to understand the manufacturing technology. The examinations included X-ray radiography, XRF analysis, optical microscopy, SEM/EDS observation and analysis, OES analysis and microhardness tests. The investigation included characterization of the composition, microstructure, thermal treatments, forge-welding junctions and slag analysis. The results revealed a heterogeneous microstructure, rich in glassy, fayalite and wüstite slag. Iron based phases included ferrite, pearlite, cementite and Widmanstätten plates, all typical to wrought iron. The forge-welds of Anchor A were located. Each arm was made of one piece, weighing about 2.5–3 kg and the shank was made of a few 1.5–2 kg pieces. The second anchor (anchor B) was only briefly examined visually and with a few radiographs, which support the results from anchor A. The research results revealed significant information about T-shaped anchors and their manufacturing process, including hot-working processes without any additional heat treatments, and folding techniques. The microstructure was similar to other ancient simple tools such as saws, sickles, axes and mortise chisels, and though the technology to make complicated structures and objects, such as swords, existed at that time, the anchors did not require this sophistication; thus simpler techniques were used, presumably because they were more cost-effective. - Highlights: ► Tantura F was a coaster dated to mid-7th–end-8th centuries. ► Two iron anchors were discovered at the Tantura F shipwreck-site. ► Anchor A was

  14. Do budget balance rules anchor budget balance expectations? -- Some international evidence

    OpenAIRE

    Rülke, Jan-Christoph; Frenkel, Michael; Lis, Eliza

    2013-01-01

    This is the first study that analyzes whether budget balance expectations are anchored and whether budget balance rules effectively anchor expectations. To this end, we use a unique data set which covers budget balance expectations in 17 countries that implemented a budget balance rules. While our results are mixed concerning the general impact of budget balance rules on anchoring expectations, we do find that specific features of budget balance rules are important to successfully anchor budg...

  15. Ultimate load capacities of expansion anchor bolts

    International Nuclear Information System (INIS)

    Czarnecki, R.M.; Manrique, M.A.; Samaddar, S.K.

    1993-01-01

    A summary of available experimental expansion anchor bolt test data is presented. These data were collected as part of programs by the nuclear industry to address generic issues related to verification of seismic adequacy of equipment in nuclear power plants. Some of the data presented are suitable for use in seismic probabilistic risk assessments. For example, mean values of ultimate strength, along with their standard deviation and coefficients of variation, for a range of most typical expansion anchor bolt sizes are presented. Effects of interaction between shear and tension, edge distance, spacing, and cracking of the concrete are presented in a manner that is more suitable for use in deterministic evaluations. Related industry programs to derive anchor bolt capacities are briefly discussed. Recommendations for areas of further investigation are also presented

  16. Do anchor investors create value for initial public offerings? An empirical investigation

    Directory of Open Access Journals (Sweden)

    Seshadev Sahoo

    2017-12-01

    Full Text Available The concept of anchor investors was introduced by the market regulator, Securities Exchange Board of India (SEBI, to bring transparency in the book building mechanism. We examine anchor investors' investment in initial public offerings (IPOs to determine how they create value for issuing firms and participating investors. Using a database of 135 IPOs issued in the Indian market through book building mechanism during 2009–2014, we find that anchor investors' investment in IPOs reduces underpricing. Larger subscription from retail investors for anchor-supported IPOs indicates that anchor investors' participation is viewed as a credible attestation of quality of the issue. We document that anchor-supported IPOs are more liquid and less volatile in the short run. We also find that by controlling for other factors such as offer size, subscription rate and age of the firm, a part of the underpricing is reduced by anchor investors.

  17. Considerations on the design of through-wall anchors

    International Nuclear Information System (INIS)

    Ricklefs, Ulf

    2012-01-01

    Connections to existing buildings are often the most difficult planning challenge for the realization of construction measures in case of piping system replacements in nuclear power plants. This is due to restricted space or limited load reserves of the building structure. Usually the realization of support connections to the existing buildings is achieved by anchor bolts. But in critical cases the preferred alternative solution uses through-wall anchors. Up to now uniform assessment thresholds are not available, no technical guidelines or regulations for construction variants exist. Through-wall anchors allow significantly higher load capacities for tensile and shear loads but require enhanced planning and realization efforts.

  18. Anchor enhanced capsulorraphy in bunionectomies using an L-shaped capsulotomy.

    Science.gov (United States)

    Gould, John S; Ali, Sheriff; Fowler, Rachel; Fleisig, Glenn S

    2003-01-01

    The objective of this study was to investigate potential benefit of a suture anchor-enhanced capsulorraphy in the early maintenance of correction in bunionectomies. We compared, retrospectively, in successive series, the loss of correction of the Hallux Valgus (HV) and intermetatarsal (IM) angle, in those repaired with an L-shaped capsulorraphy enhanced with anchors to those without. Intraoperative and second week postoperative simulated weightbearing anterior posterior (AP) X-rays were used to evaluate results. By using only intraoperative and early postoperative X-rays, we should have effectively eliminated extraneous factors that might have influenced our results. A Total of 106 cases were investigated, 65 of which were repaired using anchors, the remaining 41 without. In the anchor group, 38 underwent a proximal metatarsal concentric shelf osteotomy (CSO)/modified McBride procedure, while the remaining 27 had a distal Chevron correction. In the without-anchor group, 21 had a CSO/modified McBride procedure while 20 underwent the Chevron procedure. In the without-anchor group, the average HV and IM loss of correction was 4.60 degrees (range, -2 to 21 degrees) and 0.6 degrees (range, -1 to 9 degrees) respectively. In the anchor group, the corresponding loss was 2.8 degrees (range, -3 to 17 degrees) and 0.6 degrees (range, -2 to 14 degrees) respectively. These results, when statistically analyzed, demonstrated that while the IM angle change was not statistically significant, the HV angle change was statistically significant, implying that the anchor plays a significant role in maintaining the surgical correction in both the distal Chevron and CSO/ modified McBride bunionectomies.

  19. Surface Immobilization of Human Arginase-1 with an Engineered Ice Nucleation Protein Display System in E. coli.

    Directory of Open Access Journals (Sweden)

    Zhen Zhang

    Full Text Available Ice nucleation protein (INP is frequently used as a surface anchor for protein display in gram-negative bacteria. Here, MalE and TorA signal peptides, and three charged polypeptides, 6×Lys, 6×Glu and 6×Asp, were anchored to the N-terminus of truncated INP (InaK-N to improve its surface display efficiency for human Arginase1 (ARG1. Our results indicated that the TorA signal peptide increased the surface translocation of non-protein fused InaK-N and human ARG1 fused InaK-N (InaK-N/ARG1 by 80.7% and 122.4%, respectively. Comparably, the MalE signal peptide decreased the display efficiencies of both the non-protein fused InaK-N and InaK-N/ARG1. Our results also suggested that the 6×Lys polypeptide significantly increased the surface display efficiency of K6-InaK-N/ARG1 by almost 2-fold, while also practically abolishing the surface translocation of non-protein fused InaK-N, indicating the interesting roles of charged polypeptides in bacteria surface display systems. Cell surface-immobilized K6-InaK-N/ARG1 presented an arginase activity of 10.7 U/OD600 under the optimized conditions of 40°C, pH 10.0 and 1 mM Mn2+, which could convert more than 95% of L-Arginine (L-Arg to L-Ornithine (L-Orn in 16 hours. The engineered InaK-Ns expanded the INP surface display system, which aided in the surface immobilization of human ARG1 in E. coli cells.

  20. Stone anchors from the Okhamandal region, Gujarat Coast, India

    Digital Repository Service at National Institute of Oceanography (India)

    Sundaresh; Gaur, A.S.; Gudigar, P.; Tripati, S.; Vora, K.H.; Bandodkar, S.N.

    During marine archaeological explorations since 1983, off Dwarka, a large number of stone anchors were discovered and dated to 1400 BC, comparing with anchors found in Mediterranean waters. In recent archaeological explorations off Dwarka, Bet...

  1. Preclinical trial of a novel surface architecture for improved primary fixation of cementless orthopaedic implants.

    Science.gov (United States)

    Harrison, Noel; Field, John R; Quondamatteo, Fabio; Curtin, William; McHugh, Peter E; Mc Donnell, Pat

    2014-09-01

    A new surface architecture for cementless orthopaedic implants (OsteoAnchor), which incorporates a multitude of tiny anchor features for enhancing primary fixation, was tested in an ovine hemi-arthroplasty pilot study. Test animals were implanted with a hip stem component incorporating the OsteoAnchor surface architecture produced using additive layer manufacturing and control animals were implanted with stems containing a standard plasma sprayed titanium coating. Intra-operative surgeon feedback indicated that superior primary fixation was achieved for the OsteoAnchor stems and rapid return to normal gait and load bearing was observed post-operation. Following a 16-week recovery time, histological evaluation of the excised femurs revealed in-growth of healthy bone into the porous structure of the OsteoAnchor stems. Bone in-growth was not achieved for the plasma sprayed stems. These results indicate the potential for the OsteoAnchor surface architecture to enhance both the initial stability and long term lifetime of cementless orthopaedic implants. Copyright © 2014 Elsevier Ltd. All rights reserved.

  2. Mammalian Cell Surface Display as a Novel Method for Developing Engineered Lectins with Novel Characteristics

    Directory of Open Access Journals (Sweden)

    Keisuke Soga

    2015-07-01

    Full Text Available Leguminous lectins have a conserved carbohydrate recognition site comprising four loops (A–D. Here, we randomly mutated the sequence and length of loops C and D of peanut agglutinin (PNA and expressed the proteins on the surface of mouse green fluorescent protein (GFP-reporter cells. Flow cytometry, limiting dilution, and cDNA cloning were used to screen for several mutated PNAs with distinct properties. The mutated PNA clones obtained using NeuAcα2-6(Galβ1-3GalNAc as a ligand showed preference for NeuAcα2-6(Galβ1-3GalNAc rather than non-sialylated Galβ1-3GlcNAc, whereas wild-type PNA binds to Galβ1-3GlcNAc but not sialylated Galβ1-3GalNAc. Sequence analyses revealed that for all of the glycan-reactive mutated PNA clones, (i loop C was eight amino acids in length, (ii loop D was identical to that of wild-type PNA, (iii residue 127 was asparagine, (iv residue 125 was tryptophan, and (v residue 130 was hydrophobic tyrosine, phenylalanine, or histidine. The sugar-binding ability of wild-type PNA was increased nine-fold when Tyr125 was mutated to tryptophan, and that of mutated clone C was increased more than 30-fold after His130 was changed to tyrosine. These results provide an insight into the relationship between the amino acid sequences of the carbohydrate recognition site and sugar-binding abilities of leguminous lectins.

  3. Anchoring platinum on graphene using metallic adatoms: a first principles investigation

    International Nuclear Information System (INIS)

    Sen, F G; Alpas, A T; Qi, Y

    2012-01-01

    First principles calculations based on spin-polarized density functional theory were used to identify metallic adatoms that would strengthen the Pt(111)/graphene interface (with a low work of separation of 0.009 J m -2 ), when the adatom was placed between the Pt(111) and the graphene. It was shown that the strength of the Pt-adatom bond, which had a metallic character, increased with the amount of charge transferred from the adatom to the Pt. The carbon-adatom bond, on the other hand, had a mixed ionic and covalent character and was weaker than the Pt-adatom bond for each of the 25 elements considered. Consequently, the total Pt(111)/graphene interface strength and, hence, the anchoring effect of the adatom were controlled by the carbon-adatom bond strength. Metals with unfilled d orbitals increased the Pt/graphene interface strength to above 0.5 J m -2 . The carbon-adatom bond strength was proportional to the ratio between the charge transferred from the adatom to the graphene (ΔZ C ) and the charge transferred to the Pt surface (ΔZ Pt ); i.e., the ΔZ C /ΔZ Pt ratio defined the ability of an adatom to anchor Pt to graphene. For Ir, Os, Ru, Rh and Re, ΔZ C /ΔZ Pt > 1.0, making these elements the most effective adatoms for anchoring Pt to graphene. (paper)

  4. Design Analysis and Observed Performance of a Tieback Anchored Pile Wall in Sand

    Directory of Open Access Journals (Sweden)

    Jian-Yong Han

    2017-01-01

    Full Text Available This paper aims to study the design process and service performance of a deep excavation supported by tieback anchored pile walls. The design procedure and design approaches for deep excavation in China are described. Based on the excavation case history for Shenyang, China, design results obtained using the elastic method and the finite element method (FEM are compared and analyzed. Special emphasis is given to the analysis of horizontal wall deformations, internal forces in the wall, earth pressures on the wall, ground surface settlements, and stabilities of the excavation. The similarities and differences between the Chinese code (JGJ 120-2012 and the European code (EN 1997-1 for the design of geotechnical structures are presented based on a design example. Through the comparison, it is indicated that the Chinese code focuses on the design result, while the European code focuses on the design process. The crucial construction methods for reducing construction risk based on the excavation case history are described. The mechanical behaviors of the excavation retained by an anchored pile wall were investigated by analyzing observed field cases. The results provide good, practical guidelines for the design and construction of a tieback anchored pile wall retained excavation in sandy soil.

  5. Saponification of esters of chiral alpha-amino acids anchored through their amine function on solid support.

    Science.gov (United States)

    Cantel, Sonia; Desgranges, Stéphane; Martinez, Jean; Fehrentz, Jean-Alain

    2004-06-01

    Anchoring an alpha-amino acid residue by its amine function onto a solid support is an alternative to develop chemistry on its carboxylic function. This strategy can involve the use of amino-acid esters as precursors of the carboxylic function. A complete study on the Wang-resin was performed to determine the non racemizing saponification conditions of anchored alpha-amino esters. The use of LiOH, NaOH, NaOSi(Me)3, various solvents and temperatures were tested for this reaction. After saponification and cleavage from the support, samples were examined through their Marfey's derivatives by reversed phase HPLC to evaluate the percentage of racemization.

  6. Effectiveness of TAD-anchored maxillary protraction in late mixed dentition.

    Science.gov (United States)

    Feng, Xiaoxia; Li, Jianhua; Li, Yu; Zhao, Zhihe; Zhao, Sen; Wang, Jue

    2012-11-01

    To evaluate the effectiveness of temporary anchorage device (TAD)-anchored maxillary protraction (MP) in terms of the skeletal and dentoalveolar changes and to compare it with traditional tooth-anchored MP. A computerized literature search for relative randomized controlled trials and prospective controlled trials was performed in PubMed, MEDLINE, Cochrane Central Register of Controlled Trials, Embase, CNKI, and Google Scholar, complemented with manual search. Data extraction and quality assessment were carried out by two reviewers independently. Meta-analysis was followed when possible; otherwise, description was done. Forty articles were found, among which four trials were qualified for meta-analysis. The results showed that there was significant difference between TAD-anchored MP and untreated control in terms of maxillary advancement (weighted mean differences (WMD) 3.08 mm; 95% CI: 1.61 to approximately 4.56; P TAD-anchored MP might have a greater maxillary advancement effect and might reduce skeletal and dental side effects, compared with tooth-anchored MP.

  7. Investigation of edge plasmas in the anchor cell region of GAMMA 10

    International Nuclear Information System (INIS)

    Islam, Khairul; Nakashima, Yousuke; Yatsu, Kiyoshi

    2000-01-01

    The first results of Langmuir probe measurements at the outer transition region of the anchor cell of GAMMA 10 are given. A probe current asymmetry in vertical direction is found in this region. It is also found that the asymmetry of probe current increases in outward direction and the direction of the asymmetry is independent on movable limiter position. A relation of the plasma asymmetry with the main magnetic field configuration is investigated. Plasma flow through the non-asymmetric magnetic field configuration region is thought to be the source of plasma asymmetry in this region, i.e., ∇B and curvature drifts are responsible for the asymmetry. Possibility of cold plasma formation in the anchor cell region is obtained during plug electron cyclotron resonance heating (ECRH) and can be explained with the desorption of particles due to the collision of the drifted out particles with the wall. (author)

  8. Empirical evidence for resource-rational anchoring and adjustment.

    Science.gov (United States)

    Lieder, Falk; Griffiths, Thomas L; M Huys, Quentin J; Goodman, Noah D

    2018-04-01

    People's estimates of numerical quantities are systematically biased towards their initial guess. This anchoring bias is usually interpreted as sign of human irrationality, but it has recently been suggested that the anchoring bias instead results from people's rational use of their finite time and limited cognitive resources. If this were true, then adjustment should decrease with the relative cost of time. To test this hypothesis, we designed a new numerical estimation paradigm that controls people's knowledge and varies the cost of time and error independently while allowing people to invest as much or as little time and effort into refining their estimate as they wish. Two experiments confirmed the prediction that adjustment decreases with time cost but increases with error cost regardless of whether the anchor was self-generated or provided. These results support the hypothesis that people rationally adapt their number of adjustments to achieve a near-optimal speed-accuracy tradeoff. This suggests that the anchoring bias might be a signature of the rational use of finite time and limited cognitive resources rather than a sign of human irrationality.

  9. Inelastic seismic behavior of post-installed anchors for nuclear safety related structures: Generation of experimental database

    Energy Technology Data Exchange (ETDEWEB)

    Mahadik, Vinay, E-mail: vinay.mahadik@iwb.uni-stuttgart.de; Sharma, Akanshu; Hofmann, Jan

    2016-02-15

    for testing of fastening for use in NPP. The testing program consisted of monotonic and cyclic tests in non-cracked and cracked concrete specimens with different crack widths. In addition, crack cycling tests at design tension load, and simultaneous tension and crack cycling tests (in-phase and out-of-phase) were also conducted. The present paper deals with the details of the tests performed and the results obtained. The development of numerical models simulating anchor inelastic behavior based on the results given in the present paper will be presented in another paper.

  10. Thermal anchoring of wires in large scale superconducting coil test experiment

    International Nuclear Information System (INIS)

    Patel, Dipak; Sharma, A.N.; Prasad, Upendra; Khristi, Yohan; Varmora, Pankaj; Doshi, Kalpesh; Pradhan, S.

    2013-01-01

    Highlights: • We addressed how thermal anchoring in large scale coil test is different compare to small cryogenic apparatus? • We did precise estimation of thermal anchoring length at 77 K and 4.2 K heat sink in large scale superconducting coil test experiment. • We addressed, the quality of anchoring without covering entire wires using Kapton/Teflon tape. • We obtained excellent results in temperature measurement without using GE Varnish by doubling estimated anchoring length. -- Abstract: Effective and precise thermal anchoring of wires in cryogenic experiment is mandatory to measure temperature in milikelvin accuracy and to avoid unnecessary cooling power due to additional heat conduction from room temperature (RT) to operating temperature (OT) through potential, field, displacement and stress measurement instrumentation wires. Instrumentation wires used in large scale superconducting coil test experiments are different compare to cryogenic apparatus in terms of unique construction and overall diameter/area due to errorless measurement in large time-varying magnetic field compare to small cryogenic apparatus, often shielded wires are used. Hence, along with other variables, anchoring techniques and required thermal anchoring length are entirely different in this experiment compare to cryogenic apparatus. In present paper, estimation of thermal anchoring length of five different types of instrumentation wires used in coils test campaign at Institute for Plasma Research (IPR), India has been discussed and some temperature measurement results of coils test campaign have been presented

  11. Results of the ANCHOR prospective, multicenter registry of EndoAnchors for type Ia endoleaks and endograft migration in patients with challenging anatomy.

    Science.gov (United States)

    Jordan, William D; Mehta, Manish; Varnagy, David; Moore, William M; Arko, Frank R; Joye, James; Ouriel, Kenneth; de Vries, Jean-Paul

    2014-10-01

    Proximal attachment site complications continue to occur after endovascular repair of abdominal aortic aneurysms (EVAR), specifically type Ia endoleak and endograft migration. EndoAnchors (Aptus Endosystems, Sunnyvale, Calif) were designed to enhance endograft proximal fixation and sealing, and the current study was undertaken to evaluate the potential benefit of this treatment. During the 23-month period ending in December 2013, 319 subjects were enrolled at 43 sites in the United States and Europe. EndoAnchors were implanted in 242 patients (75.9%) at the time of an initial EVAR procedure (primary arm) and in 77 patients with an existing endograft and proximal aortic neck complications (revision arm). Technical success was defined as deployment of the desired number of EndoAnchors, adequate penetration of the vessel wall, and absence of EndoAnchor fracture. Procedural success was defined as technical success without a type Ia endoleak at completion angiography. Values are expressed as mean ± standard deviation and interquartile range. The 238 male (74.6%) and 81 female (25.4%) subjects had a mean age of 74.1 ± 8.2 years. Aneurysms averaged 58 ± 13 (51-63) mm in diameter at the time of EndoAnchor implantation (core laboratory measurements). The proximal aortic neck averaged 16 ± 13 (7-23) mm in length (42.7% <10 mm and 42.7% conical) and 27 ± 4 mm (25-30 mm) in diameter; infrarenal neck angulation was 24 ± 15 (13-34) degrees. The number of EndoAnchors deployed was 5.8 ± 2.1 (4-7). Technical success was achieved in 303 patients (95.0%) and procedural success in 279 patients (87.5%), 217 of 240 (89.7%) and 62 of 77 (80.5%) in the primary and revision arms, respectively. There were 29 residual type Ia endoleaks (9.1%) at the end of the procedure. During mean follow-up of 9.3 ± 4.7 months, 301 patients (94.4%) were free from secondary procedures. Among the 18 secondary procedures, eight were performed for residual type Ia endoleaks and the others

  12. Epididymosomes: transfer of fertility-modulating proteins to the sperm surface

    OpenAIRE

    Patricia A Martin-DeLeon

    2015-01-01

    A variety of glycosylphosphatidylinositol (GPI)-linked proteins are acquired on spermatozoa from epididymal luminal fluids (ELF) during sperm maturation. These proteins serve roles in immunoprotection and in key steps of fertilization such as capacitation, acrosomal exocytosis and sperm-egg interactions. Their acquisition on sperm cells is mediated both by membrane vesicles (epididymosomes, EP) which were first reported to dock on the sperm surface, and by lipid carriers which facilitate the ...

  13. Note on the hydrodynamic description of thin nematic films: Strong anchoring model

    KAUST Repository

    Lin, Te-Sheng; Cummings, Linda J.; Archer, Andrew J.; Kondic, Lou; Thiele, Uwe

    2013-01-01

    We discuss the long-wave hydrodynamic model for a thin film of nematic liquid crystal in the limit of strong anchoring at the free surface and at the substrate. We rigorously clarify how the elastic energy enters the evolution equation for the film thickness in order to provide a solid basis for further investigation: several conflicting models exist in the literature that predict qualitatively different behaviour. We consolidate the various approaches and show that the long-wave model derived through an asymptotic expansion of the full nemato-hydrodynamic equations with consistent boundary conditions agrees with the model one obtains by employing a thermodynamically motivated gradient dynamics formulation based on an underlying free energy functional. As a result, we find that in the case of strong anchoring the elastic distortion energy is always stabilising. To support the discussion in the main part of the paper, an appendix gives the full derivation of the evolution equation for the film thickness via asymptotic expansion. © 2013 AIP Publishing LLC.

  14. Influence of anchoring on miscarriage risk perception associated with amniocentesis.

    Science.gov (United States)

    Nuccio, Regina; Hashmi, S Shahrukh; Mastrobattista, Joan; Noblin, Sarah Jane; Refuerzo, Jerrie; Smith, Janice L; Singletary, Claire N

    2015-04-01

    One factor women consider when deciding whether to pursue amniocentesis is the risk of miscarriage. People use mechanisms like anchoring, or the prior belief regarding the magnitude of risk, as a frame of reference for new information. This study aimed to determine a woman's perception of miscarriage risk associated with amniocentesis before and after genetic counseling and to determine what factors anchor a woman's perception of miscarriage risk. One hundred thirteen women being seen for prenatal genetic counseling and possible amniocentesis at six Houston clinics participated in the two-part anonymous survey. While most women (56.7 %) perceived the risk as low or average pre-counseling and indicated the numeric risk of amniocentesis as risk as risk perception did not change after the genetic counseling session (60 %). Those who changed their feeling about the risk after counseling showed a decreased perception of the risk (p perception of the risk (p = 0.017) whereas those who declined amniocentesis were more likely to view the risk as high (p = 0.004). The only two anchoring factors that had an effect were having a friend or relative with a personal or family history of a genetic disorder (p = 0.001) and having a child already (p = 0.038); both were associated with a lower risk perception. The lack of significant factors may reflect the uniqueness of each patient's risk assessment framework and reinforces the importance of genetic counseling to elucidate individual concerns, particularly as non-invasive prenatal testing becomes more widely available and further complicates the prenatal testing landscape.

  15. Cyclic biomechanical testing of biocomposite lateral row knotless anchors in a human cadaveric model.

    Science.gov (United States)

    Barber, F Alan; Bava, Eric D; Spenciner, David B; Piccirillo, Justin

    2013-06-01

    The purpose of this study was to assess the mechanical performance of biocomposite knotless lateral row anchors based on both anchor design and the direction of pull. Two lateral row greater tuberosity insertion sites (anterior and posterior) were identified in matched pairs of fresh-frozen human cadaveric shoulders DEXA (dual energy X-ray absorptiometry) scanned to verify comparability. The humeri were stripped of all soft tissue and 3 different biocomposite knotless lateral row anchors: HEALIX Knotless BR (DePuy Mitek, Raynham MA), BioComposite PushLock (Arthrex, Naples, FL), and Bio-SwiveLock (Arthrex). Fifty-two anchors were distributed among the insertion locations and tested them with either an anatomic or axial pull. A fixed-gauge loop (15 mm) of 2 high-strength sutures from each anchor was created. After a 10-Nm preload, anchors were cycled from 10 to 45 Nm at 0.5 Hz for 200 cycles and tested to failure at 4.23 mm/second. The load to reach 3 mm and 5 mm displacement, ultimate failure load, displacement at ultimate failure, and failure mode were recorded. Threaded anchors (Bio-SwiveLock, P = .03; HEALIX Knotless, P = .014) showed less displacement with anatomic testing than did the nonthreaded anchor (BioComposite PushLock), and the HEALIX Knotless showed less overall displacement than did the other 2 anchors. The Bio-SwiveLock exhibited greater failure loads than did the other 2 anchors (P < .05). Comparison of axial and anatomic loading showed no maximum load differences for all anchors as a whole (P = .1084). Yet, anatomic pulling produced higher failure loads than did axial pulling for the Bio-SwiveLock but not for the BioComposite PushLock or the HEALIX Knotless. The nonthreaded anchor (BioComposite PushLock) displayed lower failure loads than did both threaded anchors with axial pulling. Threaded biocomposite anchors (HEALIX Knotless BR and Bio-SwiveLock) show less anatomic loading displacement and higher axial failure loads than do the nonthreaded

  16. The anchors of steel wire ropes, testing methods and their results

    Directory of Open Access Journals (Sweden)

    J. Krešák

    2012-10-01

    Full Text Available The present paper introduces an application of the acoustic and thermographic method in the defectoscopic testing of immobile steel wire ropes at the most critical point, the anchor. First measurements and their results by these new defectoscopic methods are shown. In defectoscopic tests at the anchor, the widely used magnetic method gives unreliable results, and therefore presents a problem for steel wire defectoscopy. Application of the two new methods in the steel wire defectoscopy at the anchor point will enable increased safety measures at the anchor of steel wire ropes in bridge, roof, tower and aerial cable lift constructions.

  17. Construction of Lactococcus lactis expressing secreted and anchored Eimeria tenella 3-1E protein and comparison of protective immunity against homologous challenge.

    Science.gov (United States)

    Ma, Chunli; Zhang, Lili; Gao, Mingyang; Ma, Dexing

    2017-07-01

    Two novel plasmids pTX8048-SP-Δ3-1E and pTX8048-SP-NAΔ3-1E-CWA were constructed. The plasmids were respectively electrotransformed into L. lactis NZ9000 to generate strain of L. lactis/pTX8048-SP-Δ3-1E in which 3-1E protein was expressed in secretion, and L. lactis/pTX8048-SP-NAΔ3-1E-CWA on which 3-1E protein was covalently anchored to the surface of bacteria cells. The expression of target proteins were examined by Western blot. The live lactococci expressing secreted 3-1E protein, anchored 3-1E protein, and cytoplasmic 3-1E protein was administered orally to chickens respectively, and the protective immunity and efficacy were compared by animal experiment. The results showed oral immunization to chickens with recombinant lactococci expressing anchored 3-1E protein elicited high 3-1E-specific serum IgG, increased high proportion of CD4 + and CD8α + cells in spleen, alleviated average lesion score in cecum, decreased the oocyst output per chicken compared to lactococci expressing cytoplasmic or secreted 3-1E protein. Taken together, these findings indicated the surface anchored Eimeria protein displayed by L. lacits can induce protective immunity and partial protection against homologous infection. Copyright © 2017 Elsevier Inc. All rights reserved.

  18. The anchoring bias reflects rational use of cognitive resources.

    Science.gov (United States)

    Lieder, Falk; Griffiths, Thomas L; M Huys, Quentin J; Goodman, Noah D

    2018-02-01

    Cognitive biases, such as the anchoring bias, pose a serious challenge to rational accounts of human cognition. We investigate whether rational theories can meet this challenge by taking into account the mind's bounded cognitive resources. We asked what reasoning under uncertainty would look like if people made rational use of their finite time and limited cognitive resources. To answer this question, we applied a mathematical theory of bounded rationality to the problem of numerical estimation. Our analysis led to a rational process model that can be interpreted in terms of anchoring-and-adjustment. This model provided a unifying explanation for ten anchoring phenomena including the differential effect of accuracy motivation on the bias towards provided versus self-generated anchors. Our results illustrate the potential of resource-rational analysis to provide formal theories that can unify a wide range of empirical results and reconcile the impressive capacities of the human mind with its apparently irrational cognitive biases.

  19. Changes in the sialylation and sulfation of secreted thyrotropin in congenital hypothyroidism

    International Nuclear Information System (INIS)

    Gyves, P.W.; Gesundheit, N.; Thotakura, N.R.; Stannard, B.S.; DeCherney, G.S.; Weintraub, B.D.

    1990-01-01

    The authors have examined the oligosaccharide structure of secreted thyrotropin (TSH) in perinatal and mature rats with congenital primary hypothyroidism. Rat pituitaries from euthyroid control animals and those rendered hypothyroid by methimazole treatment were incubated with [ 3 H]glucosamine in vitro. Secreted TSH was purified, and oligosaccharides were enzymatically released and characterized by anion-exchange HPLC. In perinatal hypothyroid animals compared with control animals, oligosaccharides from TSH α and β subunits contained more species with three or more negative charges. Moreover, perinatal hypothyroid animals demonstrated a dramatic increase in the ratio of sialylated to sulfated species within oligosaccharides of the same negative charge. In mature hypothyroid 9-week-old animals compared with control animals, changes were less pronounced, suggesting that endocrine regulation of oligosaccharide structure is dependent upon the maturational state of the animal. Together, these data provide direct evidence and characterization of specific changes in the structure of a secreted pituitary glycoprotein hormone occurring as a result of in vivo endocrine alterations during early development. Moreover, they provide a potential structural basis to explain the delayed clearance of both TSH and the gonadotropins with end-organ deficiency, which may have important implications for the in vivo biological activities of these hormones

  20. The relation between career anchors, occupational types and job satisfaction of midcareer employees

    Directory of Open Access Journals (Sweden)

    J. A. Ellison

    2000-06-01

    Full Text Available The objective of this research was to determine the value of the career anchor model in career decision-making. Career models that can provide the individual with greater self-insight can serve as an important guide when making career choices in todays turbulent working environment. Two hundred and ninety-five midcareer employees (managerial and non-managerial completed questionnaires to determine their career anchor, occupation type and levels of general, intrinsic and extrinsic job satisfaction. The differences in job satisfaction between employees with a fit between career anchor and occupational type and those with no such fit were compared. It was found that respondents with a fit had a significantly higher level of general and intrinsic job satisfaction than those with no such fit. It is therefore suggested that the career anchor construct could probably serve as a useful tool for midcareer employees to make career choices. Opsomming Die doel van hierdie ondersoek was om die waarde van die loopbaanankermodel in loopbaanbesluitneming te bepaal. Loopbaanmodelle wat individue van groter insig kan voorsien kan as n belangrike riglyn in vandag se turbulente werksomgewing dien. Tweehonderd vyf-en-negentig middelloopbaan-werknemers (bestuur en nie-bestuur het vraelyste voltooi om hulle loopbaanankers, beroepstipe en vlakke van algemene, intrinsieke en ekstrinsieke werkstevredenheid te bepaal. Die verskille in werkstevredenheid tussen werknemers met n passing tussen loopbaananker en beroepstipe en die sender n sodanige passing, is vergelyk. Daar is bevind dat respondente met n passing 'n beduidende hoer vlak van algemene en intrinsieke werkstevredenheid het as die sender so 'n passing. Daar word derhalwe voorgestel dat die loopbaanankermodel waarskynlik as n nuttige instrument by middelloopbaan-werknemers gebruik kan word om loopbaanbesluite te neem.

  1. Unintended anchors: Building rating systems and energy performance goals for U.S. buildings

    International Nuclear Information System (INIS)

    Klotz, Leidy; Mack, Daniel; Klapthor, Brent; Tunstall, Casey; Harrison, Jennilee

    2010-01-01

    In the U.S., where buildings account for 40% of energy use, commercial buildings use more energy per unit area than ever before. However, exemplary buildings demonstrate the feasibility of much better energy performance at no additional first cost. This research examines one possible explanation for this inconsistency. The aim is to investigate whether the anchoring bias, which refers to our tendency to gravitate towards a pre-defined standard regardless of its relevance, influences energy performance goals in building design. The scope examines professionals who help set energy performance goals for U.S. buildings. Prior to being asked to set an energy performance goal, these professionals were randomly directed to one of three series of questions. One series set an anchor of 90% energy reduction beyond standard practice, one set a 30% anchor, and one set no anchor. Respondents exposed to the 90% anchor, and respondents exposed to no anchor at all, set higher energy performance goals than respondents exposed to the 30% anchor. These results suggest that building rating systems that only reward incremental energy improvements may inadvertently create anchors, thereby discouraging more advanced energy performance goals and inhibiting energy performance that is technically and economically feasible.

  2. Anchor stabilization of trapped particle modes in mirror machines

    International Nuclear Information System (INIS)

    Berk, H.L.; Roslyakov, G.V.

    1986-07-01

    It is shown that for trapped particle modes in tandem mirrors, the pressure of the passing particles in the anchor region introduces a stabilizing term proportional to the sum of the anchor's field line curvature and total diamagnetic pressure. The theory is applied to the proposed gas dynamic trap experiment

  3. Anchor stabilization of trapped particle modes in mirror machines

    International Nuclear Information System (INIS)

    Berk, H.L.; Roslyakov, G.V.

    1986-04-01

    It is shown that for trapped particle modes in tandem mirrors, the pressure of the passing particles in the anchor region introduces a stabilizing term proportional to the sum of the anchor's field line curvature and total diamagnetic pressure. The theory is applied to the proposed gas dynamic trap experiment

  4. Fucosylated but not sialylated milk oligosaccharides diminish colon motor contractions.

    Directory of Open Access Journals (Sweden)

    John Bienenstock

    Full Text Available Human milk oligosaccharides (HMO are being studied by different groups exploring a broad range of potential beneficial effects to the breastfed infant. Many of these effects have been attributed to a growth promotion effect on certain gut organisms such as bifidobacteria. Additionally, evidence indicates that HMO are able to directly promote positive changes in gut epithelium and immune responses under certain conditions. This study utilizes a standardized ex vivo murine colon preparation to examine the effects of sialylated, fucosylated and other HMO on gut motor contractions. Only the fucosylated molecules, 2'FL and 3'FL, decreased contractility in a concentration dependent fashion. On the basis of IC50 determinations 3'FL was greater than 2 times more effective than 2'FL. The HMO 3'SL and 6'SL, lacto-N-neotetraose (LNnT, and galactooligosaccharides (GOS elicited no effects. Lactose was used as a negative control. Fucosylation seems to underlie this functional regulation of gut contractility by oligosaccharides, and L-fucose, while it was also capable of reducing contractility, was substantially less effective than 3'FL and 2'FL. These results suggest that specific HMO are unlikely to be having these effects via bifidogenesis, but though direct action on neuronally dependent gut migrating motor complexes is likely and fucosylation is important in providing this function, we cannot conclusively shown that this is not indirectly mediated. Furthermore they support the possibility that fucosylated sugars and fucose might be useful as therapeutic or preventative adjuncts in disorders of gut motility, and possibly also have beneficial central nervous system effects.

  5. Infectious Entry and Neutralization of Pathogenic JC Polyomaviruses

    Directory of Open Access Journals (Sweden)

    Eileen M. Geoghegan

    2017-10-01

    Full Text Available Summary: Progressive multifocal leukoencephalopathy (PML is a lethal brain disease caused by uncontrolled replication of JC polyomavirus (JCV. JCV strains recovered from the brains of PML patients carry mutations that prevent the engagement of sialylated glycans, which are thought to serve as receptors for the infectious entry of wild-type JCV. In this report, we show that non-sialylated glycosaminoglycans (GAGs can serve as alternative attachment receptors for the infectious entry of both wild-type and PML mutant JCV strains. After GAG-mediated attachment, PML mutant strains engage non-sialylated non-GAG co-receptor glycans, such as asialo-GM1. JCV-neutralizing monoclonal antibodies isolated from patients who recovered from PML appear to block infection by preventing the docking of post-attachment co-receptor glycans in an apical pocket of the JCV major capsid protein. Identification of the GAG-dependent/sialylated glycan-independent alternative entry pathway should facilitate the development of infection inhibitors, including recombinant neutralizing antibodies. : Geoghegan et al. show that JC polyomavirus strains that cause brain disease infect cells via a pathway involving a heparin-like attachment receptor and a non-sialylated co-receptor. Candidate therapeutic human monoclonal antibodies neutralize by blocking co-receptor engagement. Keywords: polyomavirus, JC, BK, SV40, progressive multifocal leukoencephalopathy, PML, monoclonal antibody, mAb, virus entry, receptor

  6. Functionalized Nanostructures: Redox-Active Porphyrin Anchors for Supramolecular DNA Assemblies

    KAUST Repository

    Börjesson, Karl; Wiberg, Joanna; El-Sagheer, Afaf H.; Ljungdahl, Thomas; Må rtensson, Jerker; Brown, Tom; Nordén, Bengt; Albinsson, Bo

    2010-01-01

    , such as orientation, strength, homogeneity, and binding site size, was determined, suggesting that the porphyrin is well suited as a photophysical and redox-active lipid anchor, in comparison to the inert cholesterol anchor commonly used today. Furthermore

  7. Linear and non-linear simulation of joints contact surface using ...

    African Journals Online (AJOL)

    The joint modelling including non-linear effects needs accurate and precise study of their behaviors. When joints are under the dynamic loading, micro, macro- slip happens in contact surface which is non-linear reason of the joint contact surface. The non-linear effects of joint contact surface on total behavior of structure are ...

  8. E-selectin: sialyl Lewis, a dependent adhesion of colon cancer cells, is inhibited differently by antibodies against E-selectin ligands.

    Science.gov (United States)

    Srinivas, U; Påhlsson, P; Lundblad, A

    1996-09-01

    Recent studies have demonstrated that selectins, a new family of cell-adhesion molecules with similar domain structures, mediate the adhesion of peripheral blood cells to interleukin-1 (IL-1)-activated endothelium. In the present study the authors evaluated the role of E-selectin-Sialyl Lewis x (SLe(x))/ Sialyl Lewis a (SLe(a)) interaction in mediating in vitro adhesion of two colon cancer cell lines, HT-29 and COLO 201, to human umbilical cord endothelial cells (HUVEC). Colon cancer cell lines had a strong expression of blood group-related carbohydrate epitopes as evaluated by fluorescence-activated cell sorter (FACS) analysis. It was established that adhesion of HT-29 and COLO 201 cells to IL-1 stimulated HUVEC was calcium dependent and could be inhibited by a monoclonal antibody directed against E-selectin. Prior incubation of cells with two different antibodies directed against SLe(x) and antibodies directed against related Lewis epitopes, Le(x) and Le(a), had no significant effect on adhesion. Three antibodies directed against SLe(a) differed in their capacity to inhibit the adhesion of HT-29 and COLO 201 cells to HUVEC. Only one antibody directed against the SLe(a) structure was effective in inhibiting adhesion of both COLO 201 and HT-29 cells. The difference could not be attributed to titre, the type or number of glycoproteins, or to a difference in the amount of SLe(a) present on individual proteins, suggesting that presence and right presentation of SLe(a) epitope might be important for adhesion of colon cancer cells. Finally, in the in vitro system used, adhesion of HT-29 and COLO 201 cells to activated HUVEC is mediated predominantly by E-selectin/SLe(a) interaction. SLe(x) and related epitopes, Le(x) and Le(a), seem to have limited relevance for colon cancer cell recognition of E-selectin.

  9. Steel shear strength of anchors with stand-off base plates.

    Science.gov (United States)

    2013-09-01

    Sign and signal structures are often connected to concrete foundations through a stand-off annular base plate with a double-nut anchor bolt connection, which leaves exposed anchor bolt lengths below leveling nuts used in these connections. Cantilever...

  10. Simplified design of flexible expansion anchored plates for nuclear structures

    International Nuclear Information System (INIS)

    Mehta, N.K.; Hingorani, N.V.; Longlais, T.G.; Sargent and Lundy, Chicago, IL)

    1984-01-01

    In nuclear power plant construction, expansion anchored plates are used to support pipe, cable tray and HVAC duct hangers, and various structural elements. The expansion anchored plates provide flexibility in the installation of field-routed lines where cast-in-place embedments are not available. General design requirements for expansion anchored plate assemblies are given in ACI 349, Appendix B (1). The manufacturers recommend installation procedures for their products. Recent field testing in response to NRC Bulletin 79-02 (2) indicates that anchors, installed in accordance with manufacturer's recommended procedures, perform satisfactorily under static and dynamic loading conditions. Finite element analysis is a useful tool to correctly analyze the expansion anchored plates subject to axial tension and biaxial moments, but it becomes expensive and time-consuming to apply this tool for a large number of plates. It is, therefore, advantageous to use a simplified method, even though it may be more conservative as compared to the exact method of analysis. This paper presents a design method referred to as the modified rigid plate analysis approach to simplify both the initial design and the review of as-built conditions

  11. Biomechanical advantages of triple-loaded suture anchors compared with double-row rotator cuff repairs.

    Science.gov (United States)

    Barber, F Alan; Herbert, Morley A; Schroeder, F Alexander; Aziz-Jacobo, Jorge; Mays, Matthew M; Rapley, Jay H

    2010-03-01

    To evaluate the strength and suture-tendon interface security of various suture anchors triply and doubly loaded with ultrahigh-molecular weight polyethylene-containing sutures and to evaluate the relative effectiveness of placing these anchors in a single-row or double-row arrangement by cyclic loading and then destructive testing. The infraspinatus muscle was reattached to the original humeral footprint by use of 1 of 5 different repair patterns in 40 bovine shoulders. Two single-row repairs and three double-row repairs were tested. High-strength sutures were used for all repairs. Five groups were studied: group 1, 2 triple-loaded screw suture anchors in a single row with simple stitches; group 2, 2 triple-loaded screw anchors in a single row with simple stitches over a fourth suture passed perpendicularly ("rip-stop" stitch); group 3, 2 medial and 2 lateral screw anchors with a single vertical mattress stitch passed from the medial anchors and 2 simple stitches passed from the lateral anchors; group 4, 2 medial double-loaded screw anchors tied in 2 mattress stitches and 2 push-in lateral anchors capturing the medial sutures in a "crisscross" spanning stitch; and group 5, 2 medial double-loaded screw anchors tied in 2 mattress stitches and 2 push-in lateral anchors creating a "suture-bridge" stitch. The specimens were cycled between 10 and 180 N at 1.0 Hz for 3,500 cycles or until failure. Endpoints were cyclic loading displacement (5 and 10 mm), total displacement, and ultimate failure load. A single row of triply loaded anchors was more resistant to stretching to a 5- and 10-mm gap than the double-row repairs with or without the addition of a rip-stop suture (P row repair (P row created by 2 medial double-loaded suture anchors and 2 lateral push-in anchors stretched more than any other group (P row repairs with either crossing sutures or 4 separate anchor points were more likely to fail (5- or 10-mm gap) than a single-row repair loaded with 3 simple sutures

  12. Configuration of an inelastic flexible anchored cable

    Directory of Open Access Journals (Sweden)

    T. P. Dreyer

    1992-07-01

    Full Text Available Consider an inelastic, perfectly flexible cable with given external forces acting on the total length of the cable. The one end-point is fixed in the origin and the other end-point is anchored at a given point (a;b;c in space. The resulting configuration of the cable in space can be modelled by a system of non-linear differential equations. In this article it is shown that this continuous model of the cable can always be solved in terms of an integral. In the special case of a constant (i.e. independent of the position on the cable external force per unit length the solution is given explicitly in terms of three constants that describe the tension at the origin. These three constants are determined by the boundary values a, b and c at the other end-point, and must be calculated in general by a numerical procedure from the three resulting simultaneous non-linear equations. A few applications of this method are shown.

  13. Management of subluxated capsular bag-fixated intraocular lenses using a capsular anchor

    NARCIS (Netherlands)

    Ton, Yokrat; Naftali, Modi; Lapid Gortzak, Ruth; Assia, Ehud I.

    2016-01-01

    We describe the use of the capsular anchor (AssiAnchor) to manage a subluxated intraocular lens (IOL) in the capsular bag. The anchor comprises 2 prongs that hold the anterior lens capsule and a central rod that is sutured to the scleral wall, enabling centration of the IOL-capsular bag complex. Six

  14. Suture slippage in knotless suture anchors resulting in subacromial-subdeltoid bursitis.

    Science.gov (United States)

    Hayeri, Mohammad Reza; Keefe, Daniel T; Chang, Eric Y

    2016-05-01

    Rotator cuff repair using a suture bridge and knotless suture anchors is a relatively new, but increasingly used technique. The suture bridge technique creates an anatomically similar and more secure rotator cuff repair compared with conventional arthroscopic techniques and the use of knotless anchors eliminates the challenges associated with knot tying during arthroscopic surgery. However, previous in vitro biomechanical tests have shown that the hold of the suture in a knotless suture anchor is far lower than the pullout strength of the anchor from bone. Up until now slippage has been a theoretical concern. We present a prospectively diagnosed case of in vivo suture loosening after rotator cuff repair using a knotless bridge technique resulting in subacromial-subdeltoid bursitis.

  15. Understanding Rasch Measurement: Partial Credit Model and Pivot Anchoring.

    Science.gov (United States)

    Bode, Rita K.

    2001-01-01

    Describes the Rasch measurement partial credit model, what it is, how it differs from other Rasch models, and when and how to use it. Also describes the calibration of instruments with increasingly complex items. Explains pivot anchoring and illustrates its use and describes the effect of pivot anchoring on step calibrations, item hierarchy, and…

  16. Model test of anchoring effect on zonal disintegration in deep surrounding rock masses.

    Science.gov (United States)

    Chen, Xu-Guang; Zhang, Qiang-Yong; Wang, Yuan; Liu, De-Jun; Zhang, Ning

    2013-01-01

    The deep rock masses show a different mechanical behavior compared with the shallow rock masses. They are classified into alternating fractured and intact zones during the excavation, which is known as zonal disintegration. Such phenomenon is a great disaster and will induce the different excavation and anchoring methodology. In this study, a 3D geomechanics model test was conducted to research the anchoring effect of zonal disintegration. The model was constructed with anchoring in a half and nonanchoring in the other half, to compare with each other. The optical extensometer and optical sensor were adopted to measure the displacement and strain changing law in the model test. The displacement laws of the deep surrounding rocks were obtained and found to be nonmonotonic versus the distance to the periphery. Zonal disintegration occurs in the area without anchoring and did not occur in the model under anchoring condition. By contrasting the phenomenon, the anchor effect of restraining zonal disintegration was revealed. And the formation condition of zonal disintegration was decided. In the procedure of tunnel excavation, the anchor strain was found to be alternation in tension and compression. It indicates that anchor will show the nonmonotonic law during suppressing the zonal disintegration.

  17. Model Test of Anchoring Effect on Zonal Disintegration in Deep Surrounding Rock Masses

    Directory of Open Access Journals (Sweden)

    Xu-Guang Chen

    2013-01-01

    Full Text Available The deep rock masses show a different mechanical behavior compared with the shallow rock masses. They are classified into alternating fractured and intact zones during the excavation, which is known as zonal disintegration. Such phenomenon is a great disaster and will induce the different excavation and anchoring methodology. In this study, a 3D geomechanics model test was conducted to research the anchoring effect of zonal disintegration. The model was constructed with anchoring in a half and nonanchoring in the other half, to compare with each other. The optical extensometer and optical sensor were adopted to measure the displacement and strain changing law in the model test. The displacement laws of the deep surrounding rocks were obtained and found to be nonmonotonic versus the distance to the periphery. Zonal disintegration occurs in the area without anchoring and did not occur in the model under anchoring condition. By contrasting the phenomenon, the anchor effect of restraining zonal disintegration was revealed. And the formation condition of zonal disintegration was decided. In the procedure of tunnel excavation, the anchor strain was found to be alternation in tension and compression. It indicates that anchor will show the nonmonotonic law during suppressing the zonal disintegration.

  18. Calculation of anchor forces on penetration liners for the reactor vessel Schmehausen (Germany)

    International Nuclear Information System (INIS)

    Roennert, J.K.

    1976-01-01

    Penetrations through the walls of the single cavity PCPV Prestressed Concrete Pressure Vessel for the 300 MW(e) reactor are lined with steel penetration liners welded to the liner of the cavity. For gas-tightness of the system the penetrations are closed by covers. To secure their integration with the concrete, the liners are anchored to it by means of shear studs and/or angles. Being embedded in concrete, over the full width of the walls, the liners are exposed to lateral and longitudinal concrete deformations causing forces on the anchors. The axial blow-out force due to the pressure of the coolant on the closures must also be transferred through the anchors to the concrete. In the design of anchored penetration liners stress analyses are performed to determine anchor forces under different loading conditions and at several ages of the PCPV. The present paper deals with the mathematical estimation of the anchor forces on the basis of given concrete deformations, temperature of liners, and pressure in the vessel by the method of replacing the penetration liners and their anchors by a spring model with linear stiffness characteristics for both the liner and the anchors. An example of the computations on a digital computer is shown. (author)

  19. A scale distortion theory of anchoring.

    Science.gov (United States)

    Frederick, Shane W; Mochon, Daniel

    2012-02-01

    We propose that anchoring is often best interpreted as a scaling effect--that the anchor changes how the response scale is used, not how the focal stimulus is perceived. Of importance, we maintain that this holds true even for so-called objective scales (e.g., pounds, calories, meters, etc.). In support of this theory of scale distortion, we show that prior exposure to a numeric standard changes respondents' use of that specific response scale but does not generalize to conceptually affiliated judgments rendered on similar scales. Our findings highlight the necessity of distinguishing response language effects from representational effects in places where the need for that distinction has often been assumed away.

  20. Retractable Robotic Anchor for Hard Rock and Granular Soils, Phase II

    Data.gov (United States)

    National Aeronautics and Space Administration — ProtoInnovations, LLC, is developing an innovative retractable robotic anchor that works in hard rock and granular soils permitting anchoring and subsequent...

  1. Effects of carboxyl and ester anchoring groups on solar conversion efficiencies of TiO2 dye-sensitized solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Sepehrifard, A.; Stublla, A.; Haftchenary, S.; Chen, S.; Potvin, P.; Morin, S. [York Univ., Toronto, ON (Canada). Dept. of Chemistry

    2008-07-01

    This paper reported on a study in which 2 new Ruthenium (Ru(2)) dyes bearing different anchoring groups were applied to sensitize TiO2 for dye-sensitized solar cells (DSSCs). The solar conversion efficiencies were measured. Results for 2 of the dyes which carried ester and carboxyl anchoring groups were presented. The extent and nature of the surface binding was studied using electrochemical, UV-visible, fluorescence and FTIR measurements. Solar cell performance was discussed in terms of surface concentration of chemisorbed dyes, electronic properties of the photoanodes and electrochemical properties of adsorbed dyes. The study showed that carboxylic acid groups offer better dye adsorption than ester groups. However, sensitization with warm solutions improved the adsorption of the esterified dye, most likely through transesterification. It was concluded that this may be a useful means of improving solar conversion efficiencies of ester-bearing dyes. 6 refs., 1 tab., 2 figs.

  2. Software Note: Using BILOG for Fixed-Anchor Item Calibration

    Science.gov (United States)

    DeMars, Christine E.; Jurich, Daniel P.

    2012-01-01

    The nonequivalent groups anchor test (NEAT) design is often used to scale item parameters from two different test forms. A subset of items, called the anchor items or common items, are administered as part of both test forms. These items are used to adjust the item calibrations for any differences in the ability distributions of the groups taking…

  3. Not all nutrition claims are perceived equal: anchoring effects and moderating mechanisms in food advertising.

    Science.gov (United States)

    Paek, Hye-Jin; Yoon, Hye Jin; Hove, Thomas

    2011-03-01

    Despite the increased use of health claims in food advertising, few studies have investigated how specific nutrition claims have differential effects depending on how they are presented. In this context, the current study tests the anchoring hypothesis. Anchoring refers to a common human tendency to evaluate information differently depending on the presence or absence of a numerical "anchor" or reference point. Two (pilot and main) experimental studies explore anchoring effects on audience response to food advertising both directly and moderated by cognitive, motivational, and message factors. The pilot study finds that food product ads employing nutrition claims with an anchor rather than without an anchor generate two results: First, participants perceive the product to have lower fat/lower calorie contents (anchoring hypothesis); second, they prefer the messages with an anchor over those without an anchor. The main study reports that when anchoring is successfully evoked, it produces favorable attitudes toward the ad, favorable attitudes toward the brand, and purchase intention-but only when moderated by health orientation, claim believability, and nutrition knowledge. Practical implications are provided with respect to regulatory guidelines and effective communication strategies for promoting low-fat and low-calorie products in food advertising.

  4. Career Anchors: Results of an Organisational Study in the UK.

    Science.gov (United States)

    Yarnall, Jane

    1998-01-01

    Career anchors of 374 British employees were identified using Schein's questionnaire. Age, gender, and length of service had no significant effect on distribution of anchors. Job level had some relationship. The information could be used to determine appropriate career-development strategies. (SK)

  5. Assessment of behavior, design and testing of anchors for fastening to concrete

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, Young Soo; Choi, Han Tae; Jung, Woo Young; Park, Sung Kyun [Korea Univ., Seoul (Korea, Republic of)

    1998-11-15

    This report presents the evaluation of behavior and the prediction of tensile capacity of anchors that fail concrete, as the design basis for anchorage. Tests of cast-in place headed anchors, domestically manufactured and installed in uncracked, unreinforced concrete were performed to investigate the behavior of single anchors and multiple anchors with the consideration of various embedment lengths and edge distances. The failure mode and the load-deformation response of these anchors are discussed and the concrete failure data then compared with capacities by the two exiting methods : the 45 degree cone method of ACI 349, appendix B and the Concrete Capacity Design (CCD) method. Discrepancies between the test results and these two prediction methods are assessed and also the basic differences in philosophy and the factors contributing to the philosophical differences in these two methods are addressed.

  6. Effects of anchoring and adjustment in the evaluation of product pricing.

    Science.gov (United States)

    Elaad, Eitan; Sayag, Neta; Ezer, Aliya

    2010-08-01

    Anchoring and adjustment comprise a heuristic that creates expectations. Two types of anchors were applied on participants' evaluation of products: the price reference of the product (maximum, minimum, or no price reference) and the context in which the products were evaluated (the prestige of the shopping center). Results showed that both factors anchored evaluations of products' value. Context effects were explained by the different expectations of visitors in prestigious (looking for quality) and less prestigious (seeking a bargain) centers.

  7. Characterization of the C-terminal ER membrane anchor of PTP1B

    International Nuclear Information System (INIS)

    Anderie, Ines; Schulz, Irene; Schmid, Andreas

    2007-01-01

    The tyrosine phosphatase PTP1B is an important regulator of cell function. In living cells PTP1B activity is restricted to the vicinity of the endoplasmic reticulum (ER) by post-translational C-terminal attachment of PTP1B to the ER membrane network. In our study we investigated the membrane anchor of PTP1B by use of EGFP fusion proteins. We demonstrate that the membrane anchor of PTP1B cannot be narrowed down to a unique amino acid sequence with a defined start and stop point but rather is moveable within several amino acids. Removal of up to seven amino acids from the C-terminus, as well as exchange of single amino acids in the putative transmembrane sequence did not influence subcellular localization of PTP1B. With the method of bimolecular fluorescence complementation we could demonstrate dimerization of PTP1B in vivo. Homodimerization was, in contrast to other tail-anchored proteins, not dependent on the membrane anchor. Our data demonstrate that the C-terminal membrane anchor of PTP1B is formed by a combination of a single stretch transmembrane domain (TMD) followed by a tail. TMD and tail length are variable and there are no sequence-specific features. Our data for PTP1B are consistent with a concept that explains the ER membrane anchor of tail-anchored proteins as a physicochemical structure

  8. Bone anchors or interference screws? A biomechanical evaluation for autograft ankle stabilization.

    Science.gov (United States)

    Jeys, Lee; Korrosis, Sotiris; Stewart, Todd; Harris, Nicholas J

    2004-01-01

    Autograft stabilization uses free semitendinosus tendon grafts to anatomically reconstruct the anterior talofibular ligament. Study aims were to evaluate the biomechanical properties of Mitek GII anchors compared with the Arthrex Bio-Tenodesis Screw for free tendon reconstruction of the anterior talofibular ligament. There are no differences in load to failure and percentage specimen elongation at failure between the 2 methods. Controlled laboratory study using porcine models. Sixty porcine tendon constructs were failure tested. Re-creating the pull of the anterior talofibular ligament, loads were applied at 70 degrees to the bones. Thirty-six tendons were fixed to porcine tali and tested using a single pull to failure; 10 were secured with anchors and No. 2 Ethibond, 10 with anchors and FiberWire, 10 with screws and Fiberwire, and 6 with partially gripped screws. Cyclic preloading was conducted on 6 tendons fixed by anchors and on 6 tendons fixed by screws before failure testing. Two groups of 6 components fixed to the fibula were also tested. The talus single-pull anchor group produced a mean load of 114 N and elongation of 37% at failure. The talus single-pull screw group produced a mean load of 227 N and elongation of 22% at failure (P anchors. The improved biomechanics of interference screws suggests that these may be more suited to in vivo reconstruction of the anterior talofibular ligament than are bone anchors.

  9. Anchoring in a novel bimanual coordination pattern.

    Science.gov (United States)

    Maslovat, Dana; Lam, Melanie Y; Brunke, Kirstin M; Chua, Romeo; Franks, Ian M

    2009-02-01

    Anchoring in cyclical movements has been defined as regions of reduced spatial or temporal variability [Beek, P. J. (1989). Juggling dynamics. PhD thesis. Amsterdam: Free University Press] that are typically found at movement reversal points. For in-phase and anti-phase movements, synchronizing reversal points with a metronome pulse has resulted in decreased anchor point variability and increased pattern stability [Byblow, W. D., Carson, R. G., & Goodman, D. (1994). Expressions of asymmetries and anchoring in bimanual coordination. Human Movement Science, 13, 3-28; Fink, P. W., Foo, P., Jirsa, V. K., & Kelso, J. A. S. (2000). Local and global stabilization of coordination by sensory information. Experimental Brain Research, 134, 9-20]. The present experiment examined anchoring during acquisition, retention, and transfer of a 90 degrees phase-offset continuous bimanual coordination pattern (whereby the right limb lags the left limb by one quarter cycle), involving horizontal flexion about the elbow. Three metronome synchronization strategies were imposed: participants either synchronized maximal flexion of the right arm (i.e., single metronome), both flexion and extension of the right arm (i.e., double metronome within-limb), or flexion of each arm (i.e., double metronome between-limb) to an auditory metronome. In contrast to simpler in-phase and anti-phase movements, synchronization of additional reversal points to the metronome did not reduce reversal point variability or increase pattern stability. Furthermore, practicing under different metronome synchronization strategies did not appear to have a significant effect on the rate of acquisition of the pattern.

  10. Conceptualization and Exploration of Composite Career Anchors: An Analysis of Information Systems Personnel.

    Science.gov (United States)

    Ramakrishna, Hindupur V.; Potosky, Denise

    2003-01-01

    Information systems professionals (n=163) completed measures of career anchors and outcomes (career/job satisfaction, job performance, perceived advancement prospects); 46% had multiple dominant anchors and these individuals did not have significantly different career outcomes than those with single dominant anchors. (Contains 26 references.) (SK)

  11. An anchoring system for fish habitat structures: field technique, evaluation, and application.

    Science.gov (United States)

    Barbara L. Fontaine; Thomas D. Merritt

    1988-01-01

    Steel cable can be used to bind rocks and logs together to construct fish habitat structures in streams. Cables must be securely anchored if structures are to withstand floods. This paper describes a way to anchor cables into bedrock or ballast boulders. Anchor tensile strength ranged from 7,500 to 36,500 pounds and was related to type of resin and embedment depth....

  12. Knotless single-row rotator cuff repair: a comparative biomechanical study of 2 knotless suture anchors.

    Science.gov (United States)

    Efird, Chad; Traub, Shaun; Baldini, Todd; Rioux-Forker, Dana; Spalazzi, Jeffrey P; Davisson, Twana; Hawkins, Monica; McCarty, Eric

    2013-08-01

    The purpose of this study was to compare the gap formation during cyclic loading, maximum repair strength, and failure mode of single-row full-thickness supraspinatus repairs performed using 2 knotless suture anchors with differing internal suture-retention mechanisms in a human cadaver model. Nine matched pairs of cadaver shoulders were used. Full-thickness tears were induced by detaching the supraspinatus tendon from the greater tuberosity. Single-row repairs were performed with either type I (Opus Magnum PI; ArthroCare, Austin, Texas) or type II (ReelX STT; Stryker, Mahwah, New Jersey) knotless suture anchors. The repaired tendon was cycled from 10 to 90 N for 500 cycles, followed by load to failure. Gap formation was measured at 5, 100, 200, 300, 400, and 500 cycles with a video digitizing system. Anchor type or location (anterior or posterior) had no effect on gap formation during cyclic loading regardless of position (anterior, P=.385; posterior, P=.389). Maximum load to failure was significantly greater (P=.018) for repairs performed with type II anchors (288±62 N) compared with type I anchors (179±39 N). Primary failure modes were anchor pullout and tendon tearing for type II anchors and suture slippage through the anchor for type I anchors. The internal ratcheting suture-retention mechanism of type II anchors may have helped this anchor outperform the suture-cinching mechanism of type I anchors by supporting significantly higher loads before failure and minimizing suture slippage, potentially leading to stronger repairs clinically. Copyright 2013, SLACK Incorporated.

  13. Spatial Rearrangement and Mobility Heterogeneity of an Anionic Lipid Monolayer Induced by the Anchoring of Cationic Semiflexible Polymer Chains

    Directory of Open Access Journals (Sweden)

    Xiaozheng Duan

    2016-06-01

    Full Text Available We use Monte Carlo simulations to investigate the interactions between cationic semiflexible polymer chains and a model fluid lipid monolayer composed of charge-neutral phosphatidyl-choline (PC, tetravalent anionic phosphatidylinositol 4,5-bisphosphate (PIP2, and univalent anionic phosphatidylserine (PS lipids. In particular, we explore how chain rigidity and polymer concentration influence the spatial rearrangement and mobility heterogeneity of the monolayer under the conditions where the cationic polymers anchor on the monolayer. We find that the anchored cationic polymers only sequester the tetravalent PIP2 lipids at low polymer concentrations, where the interaction strength between the polymers and the monolayer exhibits a non-monotonic dependence on the degree of chain rigidity. Specifically, maximal anchoring occurs at low polymer concentrations, when the polymer chains have an intermediate degree of rigidity, for which the PIP2 clustering becomes most enhanced and the mobility of the polymer/PIP2 complexes becomes most reduced. On the other hand, at sufficiently high polymer concentrations, the anchoring strength decreases monotonically as the chains stiffen—a result that arises from the pronounced competitions among polymer chains. In this case, the flexible polymers can confine all PIP2 lipids and further sequester the univalent PS lipids, whereas the stiffer polymers tend to partially dissociate from the monolayer and only sequester smaller PIP2 clusters with greater mobilities. We further illustrate that the mobility gradient of the single PIP2 lipids in the sequestered clusters is sensitively modulated by the cooperative effects between anchored segments of the polymers with different rigidities. Our work thus demonstrates that the rigidity and concentration of anchored polymers are both important parameters for tuning the regulation of anionic lipids.

  14. Cell wall-anchored nuclease of Streptococcus sanguinis contributes to escape from neutrophil extracellular trap-mediated bacteriocidal activity.

    Directory of Open Access Journals (Sweden)

    Chisato Morita

    Full Text Available Streptococcus sanguinis, a member of the commensal mitis group of streptococci, is a primary colonizer of the tooth surface, and has been implicated in infectious complications including bacteremia and infective endocarditis. During disease progression, S. sanguinis may utilize various cell surface molecules to evade the host immune system to survive in blood. In the present study, we discovered a novel cell surface nuclease with a cell-wall anchor domain, termed SWAN (streptococcal wall-anchored nuclease, and investigated its contribution to bacterial resistance against the bacteriocidal activity of neutrophil extracellular traps (NETs. Recombinant SWAN protein (rSWAN digested multiple forms of DNA including NET DNA and human RNA, which required both Mg(2+ and Ca(2+ for optimum activity. Furthermore, DNase activity of S. sanguinis was detected around growing colonies on agar plates containing DNA. In-frame deletion of the swan gene mostly reduced that activity. These findings indicated that SWAN is a major nuclease displayed on the surface, which was further confirmed by immuno-detection of SWAN in the cell wall fraction. The sensitivity of S. sanguinis to NET killing was reduced by swan gene deletion. Moreover, heterologous expression of the swan gene rendered a Lactococcus lactis strain more resistant to NET killing. Our results suggest that the SWAN nuclease on the bacterial surface contributes to survival in the potential situation of S. sanguinis encountering NETs during the course of disease progression.

  15. Cell wall-anchored nuclease of Streptococcus sanguinis contributes to escape from neutrophil extracellular trap-mediated bacteriocidal activity.

    Science.gov (United States)

    Morita, Chisato; Sumioka, Ryuichi; Nakata, Masanobu; Okahashi, Nobuo; Wada, Satoshi; Yamashiro, Takashi; Hayashi, Mikako; Hamada, Shigeyuki; Sumitomo, Tomoko; Kawabata, Shigetada

    2014-01-01

    Streptococcus sanguinis, a member of the commensal mitis group of streptococci, is a primary colonizer of the tooth surface, and has been implicated in infectious complications including bacteremia and infective endocarditis. During disease progression, S. sanguinis may utilize various cell surface molecules to evade the host immune system to survive in blood. In the present study, we discovered a novel cell surface nuclease with a cell-wall anchor domain, termed SWAN (streptococcal wall-anchored nuclease), and investigated its contribution to bacterial resistance against the bacteriocidal activity of neutrophil extracellular traps (NETs). Recombinant SWAN protein (rSWAN) digested multiple forms of DNA including NET DNA and human RNA, which required both Mg(2+) and Ca(2+) for optimum activity. Furthermore, DNase activity of S. sanguinis was detected around growing colonies on agar plates containing DNA. In-frame deletion of the swan gene mostly reduced that activity. These findings indicated that SWAN is a major nuclease displayed on the surface, which was further confirmed by immuno-detection of SWAN in the cell wall fraction. The sensitivity of S. sanguinis to NET killing was reduced by swan gene deletion. Moreover, heterologous expression of the swan gene rendered a Lactococcus lactis strain more resistant to NET killing. Our results suggest that the SWAN nuclease on the bacterial surface contributes to survival in the potential situation of S. sanguinis encountering NETs during the course of disease progression.

  16. Enzymatic shaving of the tegument surface of live schistosomes for proteomic analysis: a rational approach to select vaccine candidates.

    Directory of Open Access Journals (Sweden)

    William Castro-Borges

    2011-03-01

    Full Text Available The membrane-associated and membrane-spanning constituents of the Schistosoma mansoni tegument surface, the parasite's principal interface with the host bloodstream, have recently been characterized using proteomic techniques. Biotinylation of live worms using membrane-impermeant probes revealed that only a small subset of the proteins was accessible to the reagents. Their position within the multilayered architecture of the surface has not been ascertained.An enzymatic shaving approach on live worms has now been used to release the most accessible components, for analysis by MS/MS. Treatment with trypsin, or phosphatidylinositol-specific phospholipase C (PiPLC, only minimally impaired membrane integrity. PiPLC-enriched proteins were distinguished from those released in parasite vomitus or by handling damage, using isobaric tagging. Trypsin released five membrane proteins, Sm200, Sm25 and three annexins, plus host CD44 and the complement factors C3 and C4. Nutrient transporters and ion channels were absent from the trypsin fraction, suggesting a deeper location in the surface complex; surprisingly, two BAR-domain containing proteins were released. Seven parasite and two host proteins were enriched by PiPLC treatment, the vaccine candidate Sm29 being the most prominent along with two orthologues of human CD59, potentially inhibitors of complement fixation. The enzymes carbonic anhydrase and APD-ribosyl cyclase were also enriched, plus Sm200 and alkaline phosphatase. Host GPI-anchored proteins CD48 and CD90, suggest 'surface painting' during worm peregrination in the portal system.Our findings suggest that the membranocalyx secreted over the tegument surface is not the inert barrier previously proposed, some tegument proteins being externally accessible to enzymes and thus potentially located within it. Furthermore, the detection of C3 and C4 indicates that the complement cascade is initiated, while two CD59 orthologues suggest a potential

  17. Extracellular glycosylphosphatidylinositol-anchored mannoproteins and proteases of Cryptococcus neoformans.

    Science.gov (United States)

    Eigenheer, Richard A; Jin Lee, Young; Blumwald, Eduardo; Phinney, Brett S; Gelli, Angie

    2007-06-01

    Extracellular proteins of Cryptococcus neoformans are involved in the pathogenesis of cryptococcosis, and some are immunoreactive antigens that may potentially serve as candidates for vaccine development. To further study the extracellular proteome of the human fungal pathogen Cry. neoformans, we conducted a proteomic analysis of secreted and cell wall-bound proteins with an acapsular strain of Cry. neoformans. Proteins were identified from both intact cells and cell walls. In both cases, extracellular proteins were removed with trypsin or beta-glucanase, and then all proteins/peptides were purified by solid-phase extraction, spin dialysis, and HPLC, and identified by liquid chromatography-mass spectrometry. This study identified 29 extracellular proteins with a predicted N-terminal signal sequence and also a predicted glycosylphosphatidylinositol anchor motif in more than half. Among the novel proteins identified were five glycosylphosphatidylinositol-anchored proteins with extensive Ser/Thr-rich regions but no apparent functional domains, a glycosylphosphatidylinositol-anchored aspartic protease, and a metalloprotease with structural similarity to an elastinolytic metalloprotease of Aspergillus fumigatus. This study suggests that Cry. neoformans has the machinery required to target glycosylphosphatidylinositol-anchored proteins to the cell wall, and it confirms the extracellular proteolytic ability of Cry. neoformans.

  18. Apical serine protease activity is necessary for assembly of a high-resistance renal collecting duct epithelium

    DEFF Research Database (Denmark)

    Steensgaard, Mette; Svenningsen, Per; Tinning, Anne R

    2010-01-01

    Abstract AIM: We hypothesized that the serine protease prostasin is necessary for differentiation of a high resistance renal collecting duct epithelium governed by glucocorticoid. METHODS: Postnatal rat kidney and adult human kidney was used to study expression and localization of prostasin......-cadherin distribution did not change. CONCLUSION: Apical, GPI-anchored, lipid raft-associated serine protease activity, compatible with prostasin, is necessary for development of a high-resistance collecting duct epithelium....

  19. Development of a Behaviorally Anchored Rating Scale for Leadership

    Science.gov (United States)

    2018-01-01

    Research Product 2018-06 Development of a Behaviorally Anchored Rating Scale for Leadership Tatiana H. Toumbeva Krista L...anchored Rating Scale for Leadership 5a. CONTRACT NUMBER W5J9CQ-11-D-0004 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 62278 6...observer- based behavioral measure to help instructors more reliably and accurately evaluate the development of leadership attributes and competencies

  20. Enhancement of Orthodontic Anchor Screw Stability Under Immediate Loading by Ultraviolet Photofunctionalization Technology.

    Science.gov (United States)

    Takahashi, Maiko; Motoyoshi, Mitsuru; Inaba, Mizuki; Hagiwara, Yoshiyuki; Shimizu, Noriyoshi

    Ultraviolet (UV)-mediated photofunctionalization technology is intended to enhance the osseointegration capability of titanium implants. There are concerns about orthodontic anchor screws loosening under immediate loading protocols in adolescent orthodontic treatment. The purpose of this in vivo study was to evaluate the effects of photofunctionalization on the intrabony stability of orthodontic titanium anchor screws and bone-anchor screw contact under immediate loading in growing rats. Custom-made titanium anchor screws (1.4 mm in diameter and 4.0 mm in length) with or without photofunctionalization pretreatment were placed on the proximal epiphysis of the tibial bone in 6-week-old male Sprague-Dawley rats and were loaded immediately after placement. After 2 weeks of loading, the stability of the anchor screws was evaluated using a Periotest device, and the bone-anchor screw contact ratio (BSC) was assessed by a histomorphometric analysis using field-emission scanning electron microscopy. In the unloaded group, Periotest values (PTVs) were ~25 for UV-untreated screws and 13 for UVtreated screws (P < .01), while in the immediate-loading group, PTVs were 28 for UV-untreated screws and 16 for UV-treated screws (P < .05). Significantly less screw mobility was observed in both UV-treated groups regardless of the loading protocol. The BSC was increased ~1.8 fold for UV-treated screws, compared with UV-untreated screws, regardless of the loading protocol. Photofunctionalization enhanced the intrabony stability of orthodontic anchor screws under immediate loading in growing rats by increasing bone-anchor screw contact.

  1. Management of subluxated capsular bag-fixated intraocular lenses using a capsular anchor.

    Science.gov (United States)

    Ton, Yokrat; Naftali, Modi; Gortzak, Ruth Lapid; Assia, Ehud I

    2016-05-01

    We describe the use of the capsular anchor (AssiAnchor) to manage a subluxated intraocular lens (IOL) in the capsular bag. The anchor comprises 2 prongs that hold the anterior lens capsule and a central rod that is sutured to the scleral wall, enabling centration of the IOL-capsular bag complex. Six pseudophakic patients presenting with subluxated posterior chamber IOLs in the capsular bag were operated on using the device. The anchor was used successfully in all cases, although in 2 cases only 1 prong was placed under the capsulorhexis edge. In 1 eye, 2 anchors were used 1 month apart following repeated traumatic zonular injury. The capsular bag holding the IOL remained centered and stable throughout the follow-up period. The anchoring device, which was originally designed to preserve the lens capsule and stabilize subluxated crystalline lenses, can also be used to treat subluxation of a capsular bag-fixated IOL. Dr. Assia is the inventor of the AssiAnchor, has a licensed patent of the anchor, and is consultant to Hanita Lenses. Dr. Lapid-Gortzak is a consultant to and speaker for Alcon Surgical, Inc., Hanita Lenses, Orca Surgical, and Sanoculis Ltd.; a speaker for Santen; and a consultant to Icon. Drs. Ton and Naftali have no financial or proprietary interest in any material or method mentioned. Copyright © 2016 ASCRS and ESCRS. Published by Elsevier Inc. All rights reserved.

  2. Giant High-Flow Type Pulmonary Arteriovenous Malformation: Coil Embolization with Flow Control by Balloon Occlusion and an Anchored Detachable Coil

    International Nuclear Information System (INIS)

    Kanematsu, Masayuki; Kondo, Hiroshi; Goshima, Satoshi; Tsuge, Yusuke; Watanabe, Haruo; Moriyama, Noriyuki

    2012-01-01

    Pulmonary arteriovenous malformations (PAVMs) are often treated by pushable fibered or non-fibered microcoils, using an anchor or scaffold technique or with an Amplatzer plug through a guiding sheath. When performing percutaneous transcatheter microcoil embolization, there is a risk of coil migration, particularly with high-flow type PAVMs. The authors report on a unique treatment in a patient with a giant high-flow PAVM whose nidus had a maximum diameter of 6 cm. A detachable coil, not detached from a delivery wire (an anchored detachable coil), was first placed in the feeding artery under flow control by balloon occlusion, and then multiple microcoils were packed proximally to the anchored detachable coil. After confirming the stability of the microcoils during a gradual deflation of the balloon, we finally released the first detachable coil. The nidus was reduced in size to 15 mm at one year postoperatively.

  3. HKUST-1 Membranes Anchored on Porous Substrate by Hetero MIL-110 Nanorod Array Seeds.

    Science.gov (United States)

    Mao, Yiyin; Cao, Wei; Li, Junwei; Sun, Luwei; Peng, Xinsheng

    2013-09-02

    Great anchors and seeds: Hetero-seeding growth processes and anchored nanorod arrays were successfully utilized in the synthesis of HKUST-1 membranes. These arrays were firmly anchored on porous substrates by using a MIL-110 nanorod array as both the anchor and seed. The resulting HKUST-1 membranes demonstrated good separation factors for binary gases exceeding the Knudson selectivity. Copyright © 2013 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim.

  4. Smos Land Product Validation Activities at the Valencia Anchor Station

    Science.gov (United States)

    Lopez-Baeza, Ernesto

    ABSTRACT Soil moisture is a key parameter controlling the exchanges between the land surface and the atmosphere. In spite of being important for weather and climate modeling, this parameter is not well observed at a global scale. The SMOS (Soil Moisture and Ocean Salinity) Mission was designed by the European Space Agency (ESA) to measure soil moisture over continental surfaces as well as surface salinity over the oceans. Since 2001, the Valencia Anchor Station is currently being prepared for the validation of SMOS land products, namely soil moisture content and vegetation water content. The site has recently been selected by the Mission as a core validation site, mainly due to the reasonable homogeneous characteristics of the area which make it appropriate to undertake the validation of SMOS Level 2 land products during the Mission Commissioning Phase, before attempting more complex areas. Close to SMOS launch, ESA has defined and designed a SMOS V alidation Rehearsal C ampaign P lan which purpose is to repeat the Commissioning Phase execution with all centers, all tools, all participants, all structures, all data available, assuming all tools and structures are ready and trying to produce as close as possible the post-launch conditions. The aim is to test the readiness, the ensemble coordination and the speed of operations, and to avoid as far as possible any unexpected deficiencies of the plan and procedure during the real C ommissioning P hase campaigns. For the rehearsal activity, a control area of 10 x 10 km2 has been chosen at the Valencia Anchor Station study area where a network of ground soil moisture measuring stations is being set up based on the definition of homogeneous physio-hydrological units, attending to climatic, soil type, lithology, geology, elevation, slope and vegetation cover conditions. These stations are linked via a wireless communication system to a master post accessible via internet. The ground soil moisture stations will also be used

  5. Decay accelerating factor of complement is anchored to cells by a C-terminal glycolipid

    International Nuclear Information System (INIS)

    Medof, M.E.; Walter, E.I.; Roberts, W.L.; Haas, R.; Rosenberry, T.L.

    1986-01-01

    Membrane-associated decay accelerating factor (DAF) of human erythrocytes (E/sup hu/) was analyzed for a C-terminal glycolipid anchoring structure. Automated amino acid analysis of DAF following reductive radiomethylation revealed ethanolamine and glucosamine residues in proportions identical with those present in the E/sup hu/ acetylcholinesterase (AChE) anchor. Cleavage of radiomethylated 70-kilodalton (kDa) DAF with papain released the labeled ethanolamine and glucosamine and generated 61- and 55-kDa DAF products that retained all labeled Lys and labeled N-terminal Asp. Incubation of intact E/sup hu/ with phosphatidylinositol-specific phospholipase C (PI-PLC), which cleaves the anchors in trypanosome membrane form variant surface glycoproteins (mfVSGs) and murine thymocyte Thy-1 antigen, released 15% of the cell-associated DAF antigen. The released 67-kDa PI-PLC DAF derivative retained its ability to decay the classical C3 convertase C4b2a but was unable to membrane-incorporate and displayed physicochemical properties similar to urine DAF, a hydrophilic DAF form that can be isolated for urine. Nitrous acid deamination cleavage of E/sup hu/ DAF at glucosamine following labeling with the lipophilic photoreagent 3-(trifluoromethyl)-3-(m-[ 125 I]iodophenyl)diazirine ([ 125 I]TID) released the [ 125 I]TID label in a parallel fashion as from [ 125 I]TID-labeled AChE. Biosynthetic labeling of HeLa cells with [ 3 H] ethanolamine resulted in rapid 3 H incorporation into both 48-kDa pro-DAF and 72-kDa mature epithelial cell DAF. The findings indicate that DAF and AChE are anchored in E/sup hu/ by the same or a similar glycolipid structure and that, like VSGs, this structure is incorporated into DAF early in DAF biosynthesis prior to processing of pro-DAF in the Golgi

  6. Suture anchor tenodesis in repair of distal Achilles tendon injuries.

    Science.gov (United States)

    Kiliçoğlu, Onder; Türker, Mehmet; Yildız, Fatih; Akalan, Ekin; Temelli, Yener

    2014-01-01

    Distal Achilles tendon avulsions are in the form of either bony and nonbony avulsion of Achilles tendon from its calcaneal insertion. Four patients with distal Achilles tendon avulsions or ruptures which were treated with tendon to bone repair using suture anchors are presented here. Operated leg was immobilized in above-knee cast for 4 weeks while the patient walked non-weight-bearing. Then, cast was changed to below knee, and full weight-bearing was allowed. Patients underwent gait analysis minimum at first postoperative year. Mean American Orthopedics Foot Ankle Society ankle/hindfoot score of patients at last visit was 88.75 (range 85-100), and Achilles tendon total rupture score was 77.75 (range 58-87). Mean passive dorsiflexion of injured ankles (14° ± 5°) was lower than uninjured ankles (23° ± 9°). All the kinematic parameters of gait analysis were comparable to the uninjured side. Maximum plantar flexion power of injured ankle was 1.40 W/kg, and this was significantly lower than the contralateral side value 2.38 W/kg; (P = 0.0143). There were no visually altered gait or problems in daily life. Suture anchor tenodesis technique of distal Achilles tendon avulsions was successful in achieving durable osteotendinous repairs.

  7. Murasaki: a fast, parallelizable algorithm to find anchors from multiple genomes.

    Directory of Open Access Journals (Sweden)

    Kris Popendorf

    Full Text Available BACKGROUND: With the number of available genome sequences increasing rapidly, the magnitude of sequence data required for multiple-genome analyses is a challenging problem. When large-scale rearrangements break the collinearity of gene orders among genomes, genome comparison algorithms must first identify sets of short well-conserved sequences present in each genome, termed anchors. Previously, anchor identification among multiple genomes has been achieved using pairwise alignment tools like BLASTZ through progressive alignment tools like TBA, but the computational requirements for sequence comparisons of multiple genomes quickly becomes a limiting factor as the number and scale of genomes grows. METHODOLOGY/PRINCIPAL FINDINGS: Our algorithm, named Murasaki, makes it possible to identify anchors within multiple large sequences on the scale of several hundred megabases in few minutes using a single CPU. Two advanced features of Murasaki are (1 adaptive hash function generation, which enables efficient use of arbitrary mismatch patterns (spaced seeds and therefore the comparison of multiple mammalian genomes in a practical amount of computation time, and (2 parallelizable execution that decreases the required wall-clock and CPU times. Murasaki can perform a sensitive anchoring of eight mammalian genomes (human, chimp, rhesus, orangutan, mouse, rat, dog, and cow in 21 hours CPU time (42 minutes wall time. This is the first single-pass in-core anchoring of multiple mammalian genomes. We evaluated Murasaki by comparing it with the genome alignment programs BLASTZ and TBA. We show that Murasaki can anchor multiple genomes in near linear time, compared to the quadratic time requirements of BLASTZ and TBA, while improving overall accuracy. CONCLUSIONS/SIGNIFICANCE: Murasaki provides an open source platform to take advantage of long patterns, cluster computing, and novel hash algorithms to produce accurate anchors across multiple genomes with

  8. A Study on the Holding Capacity Safety Factors for Torpedo Anchors

    Directory of Open Access Journals (Sweden)

    Luís V. S. Sagrilo

    2012-01-01

    Full Text Available The use of powerful numerical tools based on the finite-element method has been improving the prediction of the holding capacity of fixed anchors employed by the offshore oil industry. One of the main achievements of these tools is the reduction of the uncertainty related to the holding capacity calculation of these anchors. Therefore, it is also possible to reduce the values of the associated design safety factors, which have been calibrated relying on models with higher uncertainty, without impairing the original level of structural safety. This paper presents a study on the calibration of reliability-based safety factors for the design of torpedo anchors considering the statistical model uncertainty evaluated using results from experimental tests and their correspondent finite-element-based numerical predictions. Both working stress design (WSD and load and resistance factors design (LRFD design methodologies are investigated. Considering the WSD design methodology, the single safety is considerably lower than the value typically employed in the design of torpedo anchors. Moreover, a LRFD design code format for torpedo anchors is more appropriate since it leads to designs having less-scattered safety levels around the target value.

  9. A study on plate anchor detailing systems of shear re-bar

    International Nuclear Information System (INIS)

    Tsurumaki, S.; Ujiie, K.; Nishikawa, T.; Kitayama, K.

    1995-01-01

    For shell walls and base slabs in reactor buildings, besides a large amount of main bars, numerous shear re-bars have been employed to resist to out-of-plane force. As a result , detailing work involving shear re-bar is extremely involved. For example, the employed re-bar anchor method differs from the ordinary methods in which, a end of shear re-bar with 135-degrees hook or with anchor plate type and another re-bar end with 90-degrees hook are used. However the structural characteristics in members using shear re-bar of the bolt-mounted anchor plate have not yet been examined. A test was performed to confirm the effects of anchor methods for shear re-bars on shearing behavior of members. This paper describes the test plan, method and results. (author). 12 figs., 7 tabs

  10. Grapnel stone anchors from Saurashtra: Remnants of Indo-Arab trade on the Indian coast

    Digital Repository Service at National Institute of Oceanography (India)

    Gaur, A.S.; Sundaresh; Tripati, S.

    Stone anchors have been used as a primary source of information on ancient navigation by marine archaeologists since long. These anchors used by ancient mariners are often noticed underwater at various places across the world. Stone anchors are also...

  11. Attaching transmitters to waterbirds using one versus two subcutaneous anchors: Retention and survival trade-offs

    Science.gov (United States)

    Lewis, Tyler; Esler, Daniel N.; Uher-Koch, Brian D.; Dickson, Rian D.; Anderson, Eric M.; Evenson, Joseph R.; Hupp, Jerry; Flint, Paul L.

    2017-01-01

    A major challenge of wildlife telemetry is choosing an attachment technique that maximizes transmitter retention while minimizing negative side effects. For waterbirds, attachment of transmitters with subcutaneous anchors has been an effective and well-established technique, having been used on >40 species. This method was recently modified to include a second subcutaneous anchor, presumably increasing transmitter retention beyond that of single-anchor attachments. This putative benefit may be offset, however, by increased health risks related to additional incisions and subcutaneous protrusions. To test this potential trade-off, we attached radiotransmitters to molting and wintering surf (Melanitta perspicillata) and white-winged scoters (M. fusca) during 2008 and 2009 in Washington State and southeast Alaska, USA, using single- (121 scoters) and double-anchor (128 scoters) attachment techniques. We estimated daily probabilities of survival and radio retention for each group, this being apparent retention for wintering scoters because we could not differentiate shed transmitters from flighted emigration. For scoters during the flightless remigial molt, we found that addition of a second anchor increased cumulative retention probability (±SE) over a 49-day period from 0.69 ± 0.11 for single-anchor to 0.88 ± 0.07 for double-anchor attachments, while having no effect on survival. However, during winter, scoters with double-anchor attachments experienced no improvement in apparent retention, while having significantly lower survival during their first 14 days following transmitter attachment; of 15 mortalities during this period, 11 had 2 subcutaneous anchors. From day 15 onward, winter survival rates were nearly identical for single- versus double-anchor attachments, indicating that adverse effects of subcutaneous anchors were mainly limited to the 14-day postattachment period. Overall, given that the survival cost of adding a second subcutaneous anchor

  12. Electrochromic mirror using viologen-anchored nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Han Na [Electronics and Telecommunications Research Institute, Nature-mimic I/O interface Research Section, 218 Gajeong-roYuseong-gu, Daejeon 305-700 (Korea, Republic of); University of Science and Technology, Advanced Device Technology, 217 Gajeong-roYuseong-gu, Daejeon 305-350 (Korea, Republic of); Cho, Seong M.; Ah, Chil Seong; Song, Juhee; Ryu, Hojun; Kim, Yong Hae [Electronics and Telecommunications Research Institute, Nature-mimic I/O interface Research Section, 218 Gajeong-roYuseong-gu, Daejeon 305-700 (Korea, Republic of); Kim, Tae-Youb, E-mail: youby@etri.re.kr [Electronics and Telecommunications Research Institute, Nature-mimic I/O interface Research Section, 218 Gajeong-roYuseong-gu, Daejeon 305-700 (Korea, Republic of); University of Science and Technology, Advanced Device Technology, 217 Gajeong-roYuseong-gu, Daejeon 305-350 (Korea, Republic of)

    2016-10-15

    Highlights: • Three types of ECM device were fabricated using viologen-anchored ECDs. • The devices were investigated according to their optical structures. • The anti-reflection material affects the reflectance and the coloration efficiency. • The device design of ECMs is a crucial factor for clear reflected images. - Abstract: Electrochromic mirrors (ECMs) that are used in automobile mirrors need to have high reflectance, a high contrast ratio, and a clear image. In particular, it is critical that distortions of clear images are minimized for safety. Therefore, an ECM is fabricated using viologen-anchored nanoparticles and a magnesium fluoride (MgF{sub 2}) layer with an anti-reflection function. The ECM has approximately 30.42% in the reflectance dynamic range and 125 cm{sup 2}/C high coloration efficiency.

  13. Quantizing non-Lagrangian gauge theories: an augmentation method

    International Nuclear Information System (INIS)

    Lyakhovich, Simon L.; Sharapov, Alexei A.

    2007-01-01

    We discuss a recently proposed method of quantizing general non-Lagrangian gauge theories. The method can be implemented in many different ways, in particular, it can employ a conversion procedure that turns an original non-Lagrangian field theory in d dimensions into an equivalent Lagrangian, topological field theory in d+1 dimensions. The method involves, besides the classical equations of motion, one more geometric ingredient called the Lagrange anchor. Different Lagrange anchors result in different quantizations of one and the same classical theory. Given the classical equations of motion and Lagrange anchor as input data, a new procedure, called the augmentation, is proposed to quantize non-Lagrangian dynamics. Within the augmentation procedure, the originally non-Lagrangian theory is absorbed by a wider Lagrangian theory on the same space-time manifold. The augmented theory is not generally equivalent to the original one as it has more physical degrees of freedom than the original theory. However, the extra degrees of freedom are factorized out in a certain regular way both at classical and quantum levels. The general techniques are exemplified by quantizing two non-Lagrangian models of physical interest

  14. Unimpeded permeation of water through biocidal graphene oxide sheets anchored on to 3D porous polyolefinic membranes

    Science.gov (United States)

    Mural, Prasanna Kumar S.; Jain, Shubham; Kumar, Sachin; Madras, Giridhar; Bose, Suryasarathi

    2016-04-01

    3D porous membranes were developed by etching one of the phases (here PEO, polyethylene oxide) from melt-mixed PE/PEO binary blends. Herein, we have systematically discussed the development of these membranes using X-ray micro-computed tomography. The 3D tomograms of the extruded strands and hot-pressed samples revealed a clear picture as to how the morphology develops and coarsens over a function of time during post-processing operations like compression molding. The coarsening of PE/PEO blends was traced using X-ray micro-computed tomography and scanning electron microscopy (SEM) of annealed blends at different times. It is now understood from X-ray micro-computed tomography that by the addition of a compatibilizer (here lightly maleated PE), a stable morphology can be visualized in 3D. In order to anchor biocidal graphene oxide sheets onto these 3D porous membranes, the PE membranes were chemically modified with acid/ethylene diamine treatment to anchor the GO sheets which were further confirmed by Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS) and surface Raman mapping. The transport properties through the membrane clearly reveal unimpeded permeation of water which suggests that anchoring GO on to the membranes does not clog the pores. Antibacterial studies through the direct contact of bacteria with GO anchored PE membranes resulted in 99% of bacterial inactivation. The possible bacterial inactivation through physical disruption of the bacterial cell wall and/or reactive oxygen species (ROS) is discussed herein. Thus this study opens new avenues in designing polyolefin based antibacterial 3D porous membranes for water purification.3D porous membranes were developed by etching one of the phases (here PEO, polyethylene oxide) from melt-mixed PE/PEO binary blends. Herein, we have systematically discussed the development of these membranes using X-ray micro-computed tomography. The 3D tomograms of the extruded strands and

  15. Cell recognition molecule L1 promotes embryonic stem cell differentiation through the regulation of cell surface glycosylation

    Energy Technology Data Exchange (ETDEWEB)

    Li, Ying [Department of Biochemistry and Molecular Biology, Dalian Medical University, Dalian 116044 (China); Department of Clinical Laboratory, Second Affiliated Hospital of Dalian Medical University, Dalian 116023 (China); Huang, Xiaohua [Department of Biochemistry and Molecular Biology, Dalian Medical University, Dalian 116044 (China); Department of Clinical Biochemistry, College of Laboratory Medicine, Dalian Medical University, Dalian 116044 (China); An, Yue [Department of Clinical Laboratory, Second Affiliated Hospital of Dalian Medical University, Dalian 116023 (China); Ren, Feng [Department of Biochemistry and Molecular Biology, Dalian Medical University, Dalian 116044 (China); Yang, Zara Zhuyun; Zhu, Hongmei; Zhou, Lei [The Key Laboratory of Stem Cell and Regenerative Medicine, Institute of Molecular and Clinical Medicine, Kunming Medical University, Kunming 650228 (China); Department of Anatomy and Developmental Biology, Monash University, Clayton 3800 (Australia); He, Xiaowen; Schachner, Melitta [Keck Center for Collaborative Neuroscience and Department of Cell Biology and Neuroscience, Rutgers University, New Brunswick, NJ (United States); Xiao, Zhicheng, E-mail: zhicheng.xiao@monash.edu [The Key Laboratory of Stem Cell and Regenerative Medicine, Institute of Molecular and Clinical Medicine, Kunming Medical University, Kunming 650228 (China); Department of Anatomy and Developmental Biology, Monash University, Clayton 3800 (Australia); Ma, Keli, E-mail: makeli666@aliyun.com [Department of Biochemistry and Molecular Biology, Dalian Medical University, Dalian 116044 (China); Li, Yali, E-mail: yalilipaper@gmail.com [Department of Biochemistry and Molecular Biology, Dalian Medical University, Dalian 116044 (China); Department of Anatomy, National University of Singapore, Singapore 119078 (Singapore)

    2013-10-25

    Highlights: •Down-regulating FUT9 and ST3Gal4 expression blocks L1-induced neuronal differentiation of ESCs. •Up-regulating FUT9 and ST3Gal4 expression in L1-ESCs depends on the activation of PLCγ. •L1 promotes ESCs to differentiate into neuron through regulating cell surface glycosylation. -- Abstract: Cell recognition molecule L1 (CD171) plays an important role in neuronal survival, migration, differentiation, neurite outgrowth, myelination, synaptic plasticity and regeneration after injury. Our previous study has demonstrated that overexpressing L1 enhances cell survival and proliferation of mouse embryonic stem cells (ESCs) through promoting the expression of FUT9 and ST3Gal4, which upregulates cell surface sialylation and fucosylation. In the present study, we examined whether sialylation and fucosylation are involved in ESC differentiation through L1 signaling. RNA interference analysis showed that L1 enhanced differentiation of ESCs into neurons through the upregulation of FUT9 and ST3Gal4. Furthermore, blocking the phospholipase Cγ (PLCγ) signaling pathway with either a specific PLCγ inhibitor or knockdown PLCγ reduced the expression levels of both FUT9 and ST3Gal4 mRNAs and inhibited L1-mediated neuronal differentiation. These results demonstrate that L1 promotes neuronal differentiation from ESCs through the L1-mediated enhancement of FUT9 and ST3Gal4 expression.

  16. Cell recognition molecule L1 promotes embryonic stem cell differentiation through the regulation of cell surface glycosylation

    International Nuclear Information System (INIS)

    Li, Ying; Huang, Xiaohua; An, Yue; Ren, Feng; Yang, Zara Zhuyun; Zhu, Hongmei; Zhou, Lei; He, Xiaowen; Schachner, Melitta; Xiao, Zhicheng; Ma, Keli; Li, Yali

    2013-01-01

    Highlights: •Down-regulating FUT9 and ST3Gal4 expression blocks L1-induced neuronal differentiation of ESCs. •Up-regulating FUT9 and ST3Gal4 expression in L1-ESCs depends on the activation of PLCγ. •L1 promotes ESCs to differentiate into neuron through regulating cell surface glycosylation. -- Abstract: Cell recognition molecule L1 (CD171) plays an important role in neuronal survival, migration, differentiation, neurite outgrowth, myelination, synaptic plasticity and regeneration after injury. Our previous study has demonstrated that overexpressing L1 enhances cell survival and proliferation of mouse embryonic stem cells (ESCs) through promoting the expression of FUT9 and ST3Gal4, which upregulates cell surface sialylation and fucosylation. In the present study, we examined whether sialylation and fucosylation are involved in ESC differentiation through L1 signaling. RNA interference analysis showed that L1 enhanced differentiation of ESCs into neurons through the upregulation of FUT9 and ST3Gal4. Furthermore, blocking the phospholipase Cγ (PLCγ) signaling pathway with either a specific PLCγ inhibitor or knockdown PLCγ reduced the expression levels of both FUT9 and ST3Gal4 mRNAs and inhibited L1-mediated neuronal differentiation. These results demonstrate that L1 promotes neuronal differentiation from ESCs through the L1-mediated enhancement of FUT9 and ST3Gal4 expression

  17. Yeast cell surface display for lipase whole cell catalyst and its applications

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Yun; Zhang, Rui; Lian, Zhongshuai; Wang, Shihui; Wright, Aaron T.

    2014-08-01

    The cell surface display technique allows for the expression of target proteins or peptides on the microbial cell surface by fusing an appropriate protein as an anchoring motif. Yeast display systems, such as Pichia pastoris, Yarowia lipolytica and Saccharomyces cerevisiae, are ideal, alternative and extensive display systems with the advantage of simple genetic manipulation and post-translational modification of expressed heterologous proteins. Engineered yeasts show high performance characteristics and variant utilizations. Herein, we comprehensively summarize the variant factors affecting lipase whole cell catalyst activity and display efficiency, including the structure and size of target proteins, screening anchor proteins, type and chain length of linkers, and the appropriate matching rules among the above-mentioned display units. Furthermore, we also address novel approaches to enhance stability and activity of recombinant lipases, such as VHb gene co-expression, multi-enzyme co-display technique, and the micro-environmental interference and self-assembly techniques. Finally, we represent the variety of applications of whole cell surface displayed lipases on yeast cells in non-aqueous phases, including synthesis of esters, PUFA enrichment, resolution of chiral drugs, organic synthesis and biofuels. We demonstrate that the lipase surface display technique is a powerful tool for functionalizing yeasts to serve as whole cell catalysts, and increasing interest is providing an impetus for broad application of this technique.

  18. Inflation targeting and the anchoring of inflation expectations in the CEE countries

    Directory of Open Access Journals (Sweden)

    Nedeljković Milan

    2017-01-01

    Full Text Available This paper studies the time evolution in the degree and level of anchoring of inflation expectations in four Central and Eastern European inflation targeting countries. The results suggest that the degree of anchoring of inflation expectations increased gradually in all countries over the last decade, while the level of implied inflation targets moved towards the official target. The extent of anchoring increased more strongly in the first years following the IT adoption and more gradually over the later period. We also find that smooth changes of the official target had a positive impact on anchoring. [Project of the Serbian Ministry of Education, Science and Technological Development, Grant no. 47028: Advancing Serbia’s Competitiveness in the Process of EU Accession

  19. Reduction of lateral loads in abutments using ground anchors

    OpenAIRE

    Laefer, Debra F.; Truong-Hong, Linh; Le, Khanh Ba

    2013-01-01

    In bridge design, economically addressing large, lateral earth pressures on bridge abutments is a major challenge. Traditional approaches employ enlargement of the abutment components to resist these pressures. This approach results in higher construction costs. As an alternative, a formal approach using ground anchors to resist lateral soil pressure on bridge abutments is proposed herein. The ground anchors are designed to minimise lateral forces at the pile cap base. Design examples for hig...

  20. Biomechanical Analysis of Suture Anchor vs Tenodesis Screw for FHL Transfer.

    Science.gov (United States)

    Drakos, Mark C; Gott, Michael; Karnovsky, Sydney C; Murphy, Conor I; DeSandis, Bridget A; Chinitz, Noah; Grande, Daniel; Chahine, Nadeen

    2017-07-01

    Chronic Achilles injury is often treated with flexor hallucis longus (FHL) tendon transfer to the calcaneus using 1 or 2 incisions. A single incision avoids the risks of extended dissections yet yields smaller grafts, which may limit fixation options. We investigated the required length of FHL autograft and biomechanical profiles for suture anchor and biotenodesis screw fixation. Single-incision FHL transfer with suture anchor or biotenodesis screw fixation to the calcaneus was performed on 20 fresh cadaveric specimens. Specimens were cyclically loaded until maximal load to failure. Length of FHL tendon harvest, ultimate load, stiffness, and mode of failure were recorded. Tendon harvest length needed for suture anchor fixation was 16.8 ± 2.1 mm vs 29.6 ± 2.4 mm for biotenodesis screw ( P = .002). Ultimate load to failure was not significantly different between groups. A significant inverse correlation existed between failure load and donor age when all specimens were pooled (ρ = -0.49, P Anchor failure occurred mostly by suture breakage (n = 8). Adequate FHL tendon length could be harvested through a single posterior incision for fixation to the calcaneus with either fixation option, but suture anchor required significantly less graft length. Stiffness, fixation strength, and load to failure were comparable between groups. An inverse correlation existed between failure load and donor age. Younger specimens with screw fixation demonstrated significantly greater failure loads. Adequate harvest length for FHL transfer could be achieved with a single posterior incision. There was no difference in strength of fixation between suture anchor and biotenodesis screw.

  1. The Effect of Suture Anchor Insertion Angle on Calcaneus Pullout Strength: Challenging the Deadman's Angle.

    Science.gov (United States)

    Weiss, William M; Saucedo, Ramon P; Robinson, John D; Lo, Chung-Chieh Jason; Morris, Randal P; Panchbhavi, Vinod K

    2017-10-01

    Refractory cases of Achilles tendinopathy amenable to surgery may include reattachment of the tendon using suture anchors. However, there is paucity of information describing the optimal insertion angle to maximize the tendon footprint and anchor stability in the calcaneus. The purpose of this investigation is to compare the fixation strength of suture anchors inserted at 90° and 45° (the Deadman's angle) relative to the primary compressive trabeculae of the calcaneus. A total of 12 matched pairs of adult cadaveric calcanei were excised and potted to approximate their alignment in vivo. Each pair was implanted with 5.5-mm bioabsorbable suture anchors placed either perpendicular (90°) or oblique (45°) to the primary compressive trabeculae. A tensile load was applied until failure of anchor fixation. Differences in failure load and stiffness between anchor fixation angles were determined by paired t-tests. No significant differences were detected between perpendicular and oblique suture anchor insertion relative to primary compressive trabeculae in terms of load to failure or stiffness. This investigation suggests that the fixation strength of suture anchors inserted perpendicular to the primary compression trabeculae and at the Deadman's angle are possibly comparable. Biomechanical comparison study.

  2. Solid phase extraction of uranium(VI) onto benzoylthiourea-anchored activated carbon

    International Nuclear Information System (INIS)

    Zhao Yongsheng; Liu Chunxia; Feng Miao; Chen Zhen; Li Shuqiong; Tian Gan; Wang Li; Huang Jingbo; Li Shoujian

    2010-01-01

    A new solid phase extractant selective for uranium(VI) based on benzoylthiourea anchored to activated carbon was developed via hydroxylation, amidation and reaction with benzoyl isothiocyanate in sequence. Fourier transform infrared spectroscopy and total element analysis proved that benzoylthiourea had been successfully grafted to the surface of the activated carbon, with a loading capacity of 1.2 mmol benzoylthiourea per gram of activated carbon. The parameters that affect the uranium(VI) sorption, such as contact time, solution pH, initial uranium(VI) concentration, adsorbent dose and temperature, have been investigated. Results have been analyzed by Langmuir and Freundlich isotherm; the former was more suitable to describe the sorption process. The maximum sorption capacity (82 mg/g) for uranium(VI) was obtained at experimental conditions. The rate constant for the uranium sorption by the as-synthesized extractant was 0.441 min -1 from the first order rate equation. Thermodynamic parameters (ΔH 0 = -46.2 kJ/mol; ΔS 0 = -98.0 J/mol K; ΔG 0 = -17.5 kJ/mol) showed the adsorption of an exothermic process and spontaneous nature, respectively. Additional studies indicated that the benzoylthiourea-anchored activated carbon (BT-AC) selectively sorbed uranyl ions in the presence of competing ions, Na + , Co 2+ , Sr 2+ , Cs + and La 3+ .

  3. Stone anchors from Sindhudurg Fort on the west coast of India

    Digital Repository Service at National Institute of Oceanography (India)

    Tripati, S.; Gaur, A.S.

    , of which there are triangular and three grapnet-type, used to construct the jetty along with the locally available sand stone. The two remaining grapnet-type anchors are erected on the jetty for mooring purposes. It is found that none of the anchors were...

  4. Non-covalently anchored multi-walled carbon nanotubes with hexa-decafluorinated zinc phthalocyanine as ppb level chemiresistive chlorine sensor

    Science.gov (United States)

    Sharma, Anshul Kumar; Mahajan, Aman; Bedi, R. K.; Kumar, Subodh; Debnath, A. K.; Aswal, D. K.

    2018-01-01

    A cost effective solution assembly method has been explored for preparing zinc(II)1,2,3,4,8,9,10,11,15,16,17,18,22,23,24,25-hexa-decafluoro-29H,31H-phthalocyanine/multi-walled carbon nanotubes (F16ZnPc/MWCNTs-COOH) hybrid. Fourier transform infrared spectroscopy (FT-IR), Raman spectroscopy, transmission electron microscopy (TEM) and field emission scanning electron microscopy (FE-SEM) investigations confirm the non-covalent anchoring of F16ZnPc onto MWCNTs-COOH through п-п stacking interactions. Further, a highly sensitive and selective chemiresistive Cl2 sensor has been fabricated using F16ZnPc/MWCNTs-COOH hybrid. The response of sensor is found to be 21.28% for 2 ppm of Cl2 with a response time of 14 s and theoretical detection limit of the sensor is found down to 0.06 ppb. The improved Cl2 sensing characteristics of hybrid are found to be originated from the synergetic interaction between F16ZnPc and MWCNTs-COOH. The underlying mechanism for improved gas sensing performance of F16ZnPc/MWCNTs-COOH sensor towards Cl2 has been explained using Raman, X-ray photoelectron spectroscopy (XPS) and electrochemical impedance spectroscopy (EIS) studies.

  5. Characterization of the Sclerotinia sclerotiorum cell wall proteome.

    Science.gov (United States)

    Liu, Longzhou; Free, Stephen J

    2016-08-01

    We used a proteomic analysis to identify cell wall proteins released from Sclerotinia sclerotiorum hyphal and sclerotial cell walls via a trifluoromethanesulfonic acid (TFMS) digestion. Cell walls from hyphae grown in Vogel's glucose medium (a synthetic medium lacking plant materials), from hyphae grown in potato dextrose broth and from sclerotia produced on potato dextrose agar were used in the analysis. Under the conditions used, TFMS digests the glycosidic linkages in the cell walls to release intact cell wall proteins. The analysis identified 24 glycosylphosphatidylinositol (GPI)-anchored cell wall proteins and 30 non-GPI-anchored cell wall proteins. We found that the cell walls contained an array of cell wall biosynthetic enzymes similar to those found in the cell walls of other fungi. When comparing the proteins in hyphal cell walls grown in potato dextrose broth with those in hyphal cell walls grown in the absence of plant material, it was found that a core group of cell wall biosynthetic proteins and some proteins associated with pathogenicity (secreted cellulases, pectin lyases, glucosidases and proteases) were expressed in both types of hyphae. The hyphae grown in potato dextrose broth contained a number of additional proteins (laccases, oxalate decarboxylase, peroxidase, polysaccharide deacetylase and several proteins unique to Sclerotinia and Botrytis) that might facilitate growth on a plant host. A comparison of the proteins in the sclerotial cell wall with the proteins in the hyphal cell wall demonstrated that sclerotia formation is not marked by a major shift in the composition of cell wall protein. We found that the S. sclerotiorum cell walls contained 11 cell wall proteins that were encoded only in Sclerotinia and Botrytis genomes. © 2015 The Authors. Molecular Plant Pathology published by British Society for Plant Pathology and John Wiley & Sons Ltd.

  6. Evaluating non-stick properties of different surface materials for contact frying

    DEFF Research Database (Denmark)

    Ashokkumar, Saranya; Adler-Nissen, Jens

    2011-01-01

    to evaluate non-stick and cleaning properties of the coatings. In accordance with industry standards pancake was selected as the food model for the non-stick properties. The performance of different frying surfaces (stainless steel, aluminium, PTFE (polytetrafluoroethylene) and three ceramic coatings with two...... on their non-stick properties, so that the smoother surfaces gave a higher force of adhesion between pancake and surface....

  7. Mimicry of the regulatory role of urokinase in lamellipodia formation by introduction of a non-native interdomain disulfide bond in its receptor

    DEFF Research Database (Denmark)

    Gårdsvoll, Henrik; Kjærgaard, Magnus; Jacobsen, Benedikte

    2011-01-01

    The high-affinity interaction between the urokinase-type plasminogen activator (uPA) and its glycolipid-anchored receptor (uPAR) plays a regulatory role for both extravascular fibrinolysis and uPAR-mediated adhesion and migration on vitronectin-coated surfaces. We have recently proposed that the ......The high-affinity interaction between the urokinase-type plasminogen activator (uPA) and its glycolipid-anchored receptor (uPAR) plays a regulatory role for both extravascular fibrinolysis and uPAR-mediated adhesion and migration on vitronectin-coated surfaces. We have recently proposed...... that the adhesive function of uPAR is allosterically regulated via a "tightening" of its three-domain structure elicited by uPA binding. To challenge this proposition, we redesigned the uPAR structure to limit its inherent conformational flexibility by covalently tethering domains DI and DIII via a non...... adhering to vitronectin. In this respect, the engineered constraint in uPAR(H47C-N259C) thus bypasses the regulatory role of uPA binding, resulting in a constitutively active uPAR. In conclusion, our data argue for a biological relevance of the interdomain dynamics of the glycolipid-anchored u...

  8. Expression of Membrane-Bound Human AminopeptidaseP as a Soluble Enzyme and an Investigation into Its Efficacy Towards Offering Protection Against the Toxicity of Chemical Warfare Nerve Agents

    Science.gov (United States)

    2016-09-01

    APP appears to be the cleavage of an N-terminal amino acid residue from peptides exhibiting a proline at P-1 residue such as bradykinin [11]. In...amino acid residue 658, replacing the Trp codon (TGG) immediately upstream of the hydrophobic peptide acting as the GPI-anchoring signal. A 6...hydrolase activity between human and chimeric recombinant mammalian paraoxonase-1 enzymes. Biochemistry, 2009. 48(43): p. 10416-22. 19. Aleti, V., et al

  9. The Membrane-anchored Serine Protease Prostasin (CAP1/PRSS8) Supports Epidermal Development and Postnatal Homeostasis Independent of Its Enzymatic Activity

    DEFF Research Database (Denmark)

    Peters, Diane E; Szabo, Roman; Friis, Stine

    2014-01-01

    The membrane-anchored serine protease prostasin (CAP1/PRSS8) is part of a cell surface proteolytic cascade that is essential for epithelial barrier formation and homeostasis. Here, we report the surprising finding that prostasin executes these functions independent of its own enzymatic activity. ...

  10. Morphometric quantification of biodegradable PLDLLA-anchor implant-beds on magnetic resonance images of the humeral head

    International Nuclear Information System (INIS)

    Chatterjee, D.

    2009-01-01

    An overview of the functional anatomy of the human shoulder joint is the base for understanding of rotator cuff tears and its surgical repair by means of suture anchors. These anchors, manufactured of biodegradable polymers, do not (or not totally) degrade in the period of time postulated by the manufactures. Bone healing seems to be impaired. Radiological follow-ups of 8 months to years postoperative revealed osteolysis and even cystic deformation of the implant beds (=anchor-holes). In this present study the anchor-holes are morphometrically measured for the first time on MRT-images. For this prospective study MRIs from altogether 38 patients (20 female/18 male, age 43.9a - 81.6a) were selected after arthroscopic rotator cuff repair with 1-4 biodegradable suture anchors (PLDLLA 'Bio-Corkscrews', Arthrex Inc., Naples FL, USA) at a single institution. After signing an informed consent form patients' MRIs could be evaluated after a mean follow-up period of 15.8 and 36 months. The shapes of the bony implant beds were subjectively categorized and for the computer-assisted morphometry of the anchor-hole areas Adobe Photoshop; CS3 Extended (Version 10.0) was used and adapted. The results were statistically analyzed and correlated with the clinical success rate (Constant Score=CS). All anchor-holes were discernable for up to 42 months. A significant shift of threaded to cylindric anchor-hole shapes was evident from the 1 st to 2 nd follow-up. Only 11.5% of the anchor-holes showed a cystic enlargement. At the 1 st follow-up the anchor-hole areas increased on average by 50.87% compared to original anchor size. However, at the 2 nd follow-up all anchor-hole areas decreased significantly (p st follow-up. The average preoperative CS improved from 38.5 points to 87.4 (1 st follow-up) and then remained at 87 points (2 nd follow-up). Anchor-holes of biodegradable suture anchor are, as opposed to the time period claimed by the manufacturers, visible and thus not totally degraded

  11. Synthesis of new copper nanoparticle-decorated anchored type ligands: Applications as non-enzymatic electrochemical sensors for hydrogen peroxide

    Energy Technology Data Exchange (ETDEWEB)

    Ensafi, Ali A., E-mail: Ensafi@cc.iut.ac.ir; Zandi-Atashbar, N.; Ghiaci, M.; Taghizadeh, M.; Rezaei, B.

    2015-02-01

    In this work, copper nanoparticles (CuNPs) decorated on two new anchored type ligands were utilized to prepare two electrochemical sensors. These ligands are made from bonding amine chains to silica support including SiO{sub 2}–pro–NH{sub 2} (compound I) and SiO{sub 2}–pro–NH–cyanuric–NH{sub 2} (compound II). The morphology of synthesized CuNPs was characterized by transmission electron microscopy (TEM). The nano-particles were in the range of 13–37 nm with the average size of 23 nm. These materials were used to modify carbon paste electrode. Different electrochemical techniques, including cyclic voltammetry, electrochemical impedance spectroscopy and hydrodynamic chronoamperometry, were used to study the sensor behavior. These electrochemical sensors were used as a model for non-enzymatic detection of hydrogen peroxide (H{sub 2}O{sub 2}). To evaluate the abilities of the modified electrodes for H{sub 2}O{sub 2} detection, the electrochemical signals were compared in the absence and presence of H{sub 2}O{sub 2}. From them, two modified electrodes showed significant responses vs. H{sub 2}O{sub 2} addition. The amperograms illustrated that the sensors were selective for H{sub 2}O{sub 2} sensing with linear ranges of 5.14–1250 μmol L{sup −1} and 1.14–1120 μmol L{sup −1} with detection limits of 0.85 and 0.27 μmol L{sup −1} H{sub 2}O{sub 2}, sensitivities of 3545 and 11,293 μA mmol{sup −1} L and with response times less than 5 s for I/CPE and II/CPE, respectively. As further verification of the selected sensor, H{sub 2}O{sub 2} contained in milk sample was analyzed and the obtained results were comparable with the ones from classical control titration method. - Highlights: • Copper nanoparticles decorating on two new anchored type ligands were prepared. • Ligands are bonding to silica support as SiO{sub 2}–pro–NH{sub 2} and SiO{sub 2}–pro–NH–cyanuric–NH{sub 2}. • These materials were used as electrochemical sensors for H

  12. Assembly and activation of alternative complement components on endothelial cell-anchored ultra-large von Willebrand factor links complement and hemostasis-thrombosis.

    Directory of Open Access Journals (Sweden)

    Nancy A Turner

    Full Text Available Vascular endothelial cells (ECs express and release protein components of the complement pathways, as well as secreting and anchoring ultra-large von Willebrand factor (ULVWF multimers in long string-like structures that initiate platelet adhesion during hemostasis and thrombosis. The alternative complement pathway (AP is an important non-antibody-requiring host defense system. Thrombotic microangiopathies can be associated with defective regulation of the AP (atypical hemolytic-uremic syndrome or with inadequate cleavage by ADAMTS-13 of ULVWF multimeric strings secreted by/anchored to ECs (thrombotic thrombocytopenic purpura. Our goal was to determine if EC-anchored ULVWF strings caused the assembly and activation of AP components, thereby linking two essential defense mechanisms.We quantified gene expression of these complement components in cultured human umbilical vein endothelial cells (HUVECs by real-time PCR: C3 and C5; complement factor (CF B, CFD, CFP, CFH and CFI of the AP; and C4 of the classical and lectin (but not alternative complement pathways. We used fluorescent microscopy, monospecific antibodies against complement components, fluorescent secondary antibodies, and the analysis of >150 images to quantify the attachment of HUVEC-released complement proteins to ULVWF strings secreted by, and anchored to, the HUVECs (under conditions of ADAMTS-13 inhibition. We found that HUVEC-released C4 did not attach to ULVWF strings, ruling out activation of the classical and lectin pathways by the strings. In contrast, C3, FB, FD, FP and C5, FH and FI attached to ULVWF strings in quantitative patterns consistent with assembly of the AP components into active complexes. This was verified when non-functional FB blocked the formation of AP C3 convertase complexes (C3bBb on ULVWF strings.AP components are assembled and activated on EC-secreted/anchored ULVWF multimeric strings. Our findings provide one possible molecular mechanism for clinical

  13. Simulation of liquid crystals. Disclinations and surface modification

    International Nuclear Information System (INIS)

    Downton, M.

    2001-01-01

    In this thesis we investigate the behaviour of molecular models liquid crystals in several different situations. Basic introductory material on liquid crystals and computer simulations is discussed in the first two chapters, we then discuss the research. The third chapter investigates the interaction between a liquid crystal and a modified surface. A confined system of hard spherocylinders in a slab geometry is examined. The surface consists of planar hard walls with elongated molecules grafted perpendicularly onto them. The concentration of grafted molecules is varied to give different surfaces. Several different behaviours are found including planar, homeotropic and tilted anchorings of the liquid crystal. Molecular dynamics simulations of a nematic liquid crystal in slab geometry with twisted boundary conditions are performed. By arranging the initial configuration suitably it is possible to create a simulation cell with two regions of opposite twist separated by a strength half disclination line. The properties of the line are examined both with and without an applied external field. Finally, we again examine the system of grafted molecules on a flat substrate using an atomistic model of both the liquid crystal and the surface molecules. Again the effect of varying the density of grafted molecules is found to change the anchoring characteristics of the surface; both homeotropic and planar anchorings are observed. (author)

  14. Characterizing the flow of stirred vessels with anchor type impellers

    Directory of Open Access Journals (Sweden)

    S.M.C. Peixoto

    2000-12-01

    Full Text Available Despite its importance in chemical industries, there are few works which studies anchor type impellers and only a fraction of the works investigate these systems under a computational approach. The great majority refers to turbine impellers, specially Rushton turbines, under turbulent flow. Anchor impellers are used specially for highly viscous flow, typical of polymer reactions. The viscosity is normally in the range 1000-10000 cp. Since this range of viscosity describe highly viscous flows, the reactions for anchor agitated systems are normally carried out under laminar flow. This work presents a detailed computational fluid dynamics (CFD approach to study the behaviour of stirred vessels using anchor impellers. The axial plane of the tank, which is being modelled, is divided into small control volumes, which collectively is referred to as the mesh, or grid. In each of these cells the momentum balance, energy and mass conservation, which describes the model, are rewritten algebraically using the finite volumes method to relate such variables as velocity, pressure and temperature to values in neighbouring cells. The equations are then solved numerically, and the results yield the flow corresponding to the model. Since the geometry of a vessel with anchor impellers strictly calls for a three dimensional method, an approximation is made to account for the effect of the blades (Kuncewics, 1992. The main objective of this work is to give a detailed description of the flow generated by this axial impeller with a view to indicate ways in which the design and operation of these systems can be improved.

  15. Model for ion confinement in a hot-electron tandem mirror anchor

    International Nuclear Information System (INIS)

    Baldwin, D.E.

    1980-01-01

    Anisotropic, hot electrons trapped in local minimum-B wells have been proposed as MHD-stabilizing anchors to an otherwise axisymmetric tandem configuration. This work describes a model for plasma confinement between the anchors and the remainder of the system and calcuates the power loss implied by maintenance of this plasma

  16. Bioabsorbable Suture Anchor Migration to the Acromioclavicular Joint: How Far Can These Implants Go?

    Directory of Open Access Journals (Sweden)

    Giovanna Medina

    2014-01-01

    Full Text Available Few complications regarding the use of bioabsorbable suture anchors in the shoulder have been reported. What motivated this case report was the unusual location of the anchor, found in the acromioclavicular joint which, to our knowledge, has never been reported so far. A 53-year old male with previous rotator cuff (RC repair using bioabsorbable suture anchors presented with pain and weakness after 2 years of surgery. A suspicion of retear of the RC led to request of a magnetic resonance image, in which the implant was found located in the acromioclavicular joint. The complications reported with the use of metallic implants around the shoulder led to the development of bioabsorbable anchors. Advantages are their absorption over time, minimizing the risk of migration or interference with revision surgery, less artifacts with magnetic resonance imaging, and tendon-to-bone repair strength similar to metallic anchors. Since the use of bioabsorbable suture anchors is increasing, it is important to know the possible complications associated with these devices.

  17. The cellular prion protein interacts with the tissue non-specific alkaline phosphatase in membrane microdomains of bioaminergic neuronal cells.

    Directory of Open Access Journals (Sweden)

    Myriam Ermonval

    Full Text Available BACKGROUND: The cellular prion protein, PrP(C, is GPI anchored and abundant in lipid rafts. The absolute requirement of PrP(C in neurodegeneration associated to prion diseases is well established. However, the function of this ubiquitous protein is still puzzling. Our previous work using the 1C11 neuronal model, provided evidence that PrP(C acts as a cell surface receptor. Besides a ubiquitous signaling function of PrP(C, we have described a neuronal specificity pointing to a role of PrP(C in neuronal homeostasis. 1C11 cells, upon appropriate induction, engage into neuronal differentiation programs, giving rise either to serotonergic (1C11(5-HT or noradrenergic (1C11(NE derivatives. METHODOLOGY/PRINCIPAL FINDINGS: The neuronal specificity of PrP(C signaling prompted us to search for PrP(C partners in 1C11-derived bioaminergic neuronal cells. We show here by immunoprecipitation an association of PrP(C with an 80 kDa protein identified by mass spectrometry as the tissue non-specific alkaline phosphatase (TNAP. This interaction occurs in lipid rafts and is restricted to 1C11-derived neuronal progenies. Our data indicate that TNAP is implemented during the differentiation programs of 1C11(5-HT and 1C11(NE cells and is active at their cell surface. Noteworthy, TNAP may contribute to the regulation of serotonin or catecholamine synthesis in 1C11(5-HT and 1C11(NE bioaminergic cells by controlling pyridoxal phosphate levels. Finally, TNAP activity is shown to modulate the phosphorylation status of laminin and thereby its interaction with PrP. CONCLUSION/SIGNIFICANCE: The identification of a novel PrP(C partner in lipid rafts of neuronal cells favors the idea of a role of PrP in multiple functions. Because PrP(C and laminin functionally interact to support neuronal differentiation and memory consolidation, our findings introduce TNAP as a functional protagonist in the PrP(C-laminin interplay. The partnership between TNAP and PrP(C in neuronal cells may

  18. Experimental Study On Lateral Load Capacity of Bamboo RC Beam Column Joints Strengthened By Bamboo Mechanical Anchors

    Directory of Open Access Journals (Sweden)

    Sri Umniati B.

    2017-01-01

    Full Text Available In this paper, the prospective of bamboos which available abundantly especially in Indonesia as rebars and mechanical anchors are studied. And also the endurance of the bamboos mechanical anchors to withstand cyclic loading were observed. Nine classes of bamboos bar were evaluated: consist of 3 different anchors (0, 4 and 8 anchors and 3 different compressive strength (19.19 MPa, 29.61 MPa and 37.96 MPa means 3 × 3 parameters. The results show that the lateral load capacity increased significantly with the present of bamboo anchors specimens: 26.04 % for 4 anchors specimens (C2 and 25 % for the 8 anchors specimens (C3 compared to zero anchor specimens (C1. On the other hand, the compressive strength of concrete have no significant effects to the lateral load capacity. Overall it can be concluded that, bamboo can be used as mechanical anchorage to strengthen beam column joint.

  19. Lipid transfer proteins do their thing anchored at membrane contact sites… but what is their thing?

    Science.gov (United States)

    Wong, Louise H; Levine, Tim P

    2016-04-15

    Membrane contact sites are structures where two organelles come close together to regulate flow of material and information between them. One type of inter-organelle communication is lipid exchange, which must occur for membrane maintenance and in response to environmental and cellular stimuli. Soluble lipid transfer proteins have been extensively studied, but additional families of transfer proteins have been identified that are anchored into membranes by transmembrane helices so that they cannot diffuse through the cytosol to deliver lipids. If such proteins target membrane contact sites they may be major players in lipid metabolism. The eukaryotic family of so-called Lipid transfer proteins Anchored at Membrane contact sites (LAMs) all contain both a sterol-specific lipid transfer domain in the StARkin superfamily (related to StART/Bet_v1), and one or more transmembrane helices anchoring them in the endoplasmic reticulum (ER), making them interesting subjects for study in relation to sterol metabolism. They target a variety of membrane contact sites, including newly described contacts between organelles that were already known to make contact by other means. Lam1-4p target punctate ER-plasma membrane contacts. Lam5p and Lam6p target multiple contacts including a new category: vacuolar non-NVJ cytoplasmic ER (VancE) contacts. These developments confirm previous observations on tubular lipid-binding proteins (TULIPs) that established the importance of membrane anchored proteins for lipid traffic. However, the question remaining to be solved is the most difficult of all: are LAMs transporters, or alternately are they regulators that affect traffic more indirectly? © 2016 Authors; published by Portland Press Limited.

  20. Extremal surface barriers

    International Nuclear Information System (INIS)

    Engelhardt, Netta; Wall, Aron C.

    2014-01-01

    We present a generic condition for Lorentzian manifolds to have a barrier that limits the reach of boundary-anchored extremal surfaces of arbitrary dimension. We show that any surface with nonpositive extrinsic curvature is a barrier, in the sense that extremal surfaces cannot be continuously deformed past it. Furthermore, the outermost barrier surface has nonnegative extrinsic curvature. Under certain conditions, we show that the existence of trapped surfaces implies a barrier, and conversely. In the context of AdS/CFT, these barriers imply that it is impossible to reconstruct the entire bulk using extremal surfaces. We comment on the implications for the firewall controversy

  1. Career anchors and career resilience: Supplementary constructs?

    Directory of Open Access Journals (Sweden)

    L. J. Van Vuuren

    2000-06-01

    Full Text Available Previously the authors reported on a study in which an attempt was made at defining and measuring the construct career resilience (Fourie & Van Vuuren, 1998. The present article continues this investigation by reporting on the relationship between career resilience and career anchors, as defined in Scheins (1975; 1978; 1990; 1992 career anchor model. The aim of the study was to determine whether career anchor patterning could potentially inhibit or facilitate individuals' levels of career resilience. The "Career Resilience Questionnaire" (CRQ (Fourie & Van Vuuren, 1998 together with Scheins (1990 "Career Orientations Inventory" (COI were administered to 352 skilled employees. The findings regarding the statistical relationship between the two constructs are discussed. Opsomming Loopbaanankers en loopbaangehardheid: supplementere konstrukte? In n vorige publikasie van Fourie en Van Vuuren (1998 is die bevindinge aangaande die afbakening en meting van die konstruk, loopbaangehardheid, gerapporteer. In die huidige artikel word die ondersoek voortgesit met 'n beskrywing van die verwantskap tussen loopbaangehardheid en loopbaanankers, soos gedefinieer in die loopbaanankermodel van Schein (1975; 1978; 1990; 1992. Die doel met die studie was om te bepaal of die mate van loopbaanankerontplooiing individuele vlakke van loopbaangehardheid potensieel fasiliteer ofinhibeer. Die "Career Resilience Questionnaire" (CRQ (Fourie & Van Vuuren, 1998 is tesame met die "Career Orientation Inventory" (COI (Schein, 1990 op 352 geskoolde werknemers geadministreer. Die bevindinge betreffende die statistiese verwantskap tussen die twee konstrukte word bespreek.

  2. Robust non-wetting PTFE surfaces by femtosecond laser machining.

    Science.gov (United States)

    Liang, Fang; Lehr, Jorge; Danielczak, Lisa; Leask, Richard; Kietzig, Anne-Marie

    2014-08-08

    Nature shows many examples of surfaces with extraordinary wettability,which can often be associated with particular air-trapping surface patterns. Here,robust non-wetting surfaces have been created by femtosecond laser ablation of polytetrafluoroethylene (PTFE). The laser-created surface structure resembles a forest of entangled fibers, which support structural superhydrophobicity even when the surface chemistry is changed by gold coating. SEM analysis showed that the degree of entanglement of hairs and the depth of the forest pattern correlates positively with accumulated laser fluence and can thus be influenced by altering various laser process parameters. The resulting fibrous surfaces exhibit a tremendous decrease in wettability compared to smooth PTFE surfaces; droplets impacting the virgin or gold coated PTFE forest do not wet the surface but bounce off. Exploratory bioadhesion experiments showed that the surfaces are truly air-trapping and do not support cell adhesion. Therewith, the created surfaces successfully mimic biological surfaces such as insect wings with robust anti-wetting behavior and potential for antiadhesive applications. In addition, the fabrication can be carried out in one process step, and our results clearly show the insensitivity of the resulting non-wetting behavior to variations in the process parameters,both of which make it a strong candidate for industrial applications.

  3. Robust Non-Wetting PTFE Surfaces by Femtosecond Laser Machining

    Directory of Open Access Journals (Sweden)

    Fang Liang

    2014-08-01

    Full Text Available Nature shows many examples of surfaces with extraordinary wettability, which can often be associated with particular air-trapping surface patterns. Here, robust non-wetting surfaces have been created by femtosecond laser ablation of polytetrafluoroethylene (PTFE. The laser-created surface structure resembles a forest of entangled fibers, which support structural superhydrophobicity even when the surface chemistry is changed by gold coating. SEM analysis showed that the degree of entanglement of hairs and the depth of the forest pattern correlates positively with accumulated laser fluence and can thus be influenced by altering various laser process parameters. The resulting fibrous surfaces exhibit a tremendous decrease in wettability compared to smooth PTFE surfaces; droplets impacting the virgin or gold coated PTFE forest do not wet the surface but bounce off. Exploratory bioadhesion experiments showed that the surfaces are truly air-trapping and do not support cell adhesion. Therewith, the created surfaces successfully mimic biological surfaces such as insect wings with robust anti-wetting behavior and potential for antiadhesive applications. In addition, the fabrication can be carried out in one process step, and our results clearly show the insensitivity of the resulting non-wetting behavior to variations in the process parameters, both of which make it a strong candidate for industrial applications.

  4. Factors related to furniture anchoring: a method for reducing harm during earthquakes.

    Science.gov (United States)

    Haraoka, Tomoko; Hayasaka, Shinya; Murata, Chiyoe; Yamaoka, Taiji; Ojima, Toshiyuki

    2013-02-01

    Fatalities and injuries during an earthquake can be reduced by taking preemptive measures before-hand, and furniture anchoring is an important safety measure for all residents. This study sought to clarify the factors associated with furniture anchoring within the home. A self-administered mail survey was completed from July to August 2010 by 3500 men and women between the ages of 20 and 69 years who were chosen at random from an official government resident registry of 2 cities in Japan. Of the 1729 valid responses, 37.1% reported furniture anchoring. An association with furniture anchoring was observed for having viewed earthquake intensity maps or damage predictions (odds ratio [OR] 1.92, 95% C1 1.54-2.39), expressing concern about a future earthquake (OR 2.07, 95% C1 1.36-3.15), feelings of urgency (OR 1.90, 95% CI 1.47-2.45), accuracy of the government disaster preparedness information (OR 1.68, 95% CI 1.17-2.42), knowledge of the meaning of emergency earthquake warnings (OR 1.67, 95% CI 1.12-2.48), and participation in voluntary disaster preparedness activities (OR 1.40, 95% C1 1.12-1.75). Furniture anchoring was found to be associated with risk awareness, risk perception, disaster preparedness information provided by government to residents, knowledge of earthquakes, participation in voluntary disaster preparedness activities, nonwooden structures, and marital status. An increase in furniture anchoring is important and can be achieved through education and training in daily life.

  5. Small-angle light scattering symmetry breaking in polymer-dispersed liquid crystal films with inhomogeneous electrically controlled interface anchoring

    Energy Technology Data Exchange (ETDEWEB)

    Loiko, V. A., E-mail: loiko@ifanbel.bas-net.by; Konkolovich, A. V. [National Academy of Sciences of Belarus, Stepanov Institute of Physics (Belarus); Zyryanov, V. Ya. [Russian Academy of Sciences, Kirensky Institute of Physics, Federal Research Center “Krasnoyarsk Scientific Center,” Siberian Branch (Russian Federation); Miskevich, A. A. [National Academy of Sciences of Belarus, Stepanov Institute of Physics (Belarus)

    2017-03-15

    We have described the method of analyzing and reporting on the results of calculation of the small-angle structure of radiation scattered by a polymer-dispersed liquid crystal film with electrically controlled interfacial anchoring. The method is based on the interference approximation of the wave scattering theory and the hard disk model. Scattering from an individual liquid crystal droplet has been described using the anomalous diffraction approximation extended to the case of droplets with uniform and nonuniform interface anchoring at the droplet–polymer boundary. The director field structure in an individual droplet is determined from the solution of the problem of minimizing the volume density of the free energy. The electrooptical effect of symmetry breaking in the angular distribution of scattered radiation has been analyzed. This effect means that the intensities of radiation scattered within angles +θ{sub s} and–θ{sub s} relative to the direction of illumination in the scattering plane can be different. The effect is of the interference origin and is associated with asymmetry of the phase shift of the wavefront of an incident wave from individual parts of the droplet, which appears due to asymmetry of the director field structure in the droplet, caused by nonuniform anchoring of liquid crystal molecules with the polymer on its surface. This effect is analyzed in the case of normal illumination of the film depending on the interfacial anchoring at the liquid crystal–polymer interface, the orientation of the optical axes of droplets, their concentration, sizes, anisometry, and polydispersity.

  6. Career Anchors: Distribution and Impact on Job Satisfaction, the Israeli Case

    Science.gov (United States)

    Danziger, Nira; Valency, Rony

    2006-01-01

    Purpose: The purpose of this paper is to examine the career anchor concept developed by Edgar Schein. Design/methodology/approach: The paper focuses on the distribution of the eight career anchors, on a large heterogeneous sample and the differences in the distribution by gender and type of employment; and the impact of the congruence on job…

  7. Contact area and pressure in suture bridge rotator cuff repair using knotless lateral anchors.

    Science.gov (United States)

    Tompkins, Marc; Monchik, Keith O; Plante, Matthew J; Fleming, Braden C; Fadale, Paul D

    2011-10-01

    To evaluate whether the use of knotless lateral anchors in a suture bridge construct produces better contact area and pressure parameters than a suture bridge construct with standard lateral anchors that require knots or a double-row repair. The hypothesis was that knotless lateral anchors would produce better contact area and pressure parameters than the other two constructs. A total of fifteen matched pairs of cadaveric shoulders were divided into three groups. In Group 1, a suture bridge using knotless anchors for the lateral row was performed on five shoulders. A suture bridge using standard lateral row anchors that require knots was performed on the contralateral shoulders. In Group 2, suture bridge with knotless lateral row anchors was compared with double-row repair. In Group 3, suture bridge using standard lateral row anchors was compared with double-row repair. The contact conditions of the rotator cuff footprint were measured using pressure-sensitive film. There were no statistically significant differences between any of the techniques regarding contact area F(2, 15.7) = 3.09, P = 0.07 or mean contact pressure F(2, 15.1) = 2.35, P = 0.12. A post hoc power analysis suggests differences between techniques are likely less than 91-113 mm(2) for area and 0.071-0.089 N for pressure. The use of knotless anchors in the lateral row of a suture bridge repair did not increase the footprint contact area or contact pressure when compared to a suture bridge repair requiring knots laterally or to a double-row repair.

  8. Straightforward and robust synthesis of monodisperse surface-functionalized gold nanoclusters

    Directory of Open Access Journals (Sweden)

    Silvia Varela-Aramburu

    2016-09-01

    Full Text Available Gold nanoclusters are small (1–3 nm nanoparticles with a high surface area that are useful for biomedical studies and drug delivery. The synthesis of small, surface-functionalized gold nanoclusters is greatly dependent on the reaction conditions. Here, we describe a straightforward, efficient and robust room temperature one-pot synthesis of 2 nm gold nanoclusters using thioglucose as a reducing and stabilizing agent, which was discovered by serendipity. The resultant monodisperse gold nanoclusters are more stable than those generated using some other common methods. The carboxylic acid contained in the stabilizing agent on the cluster surface serves as anchor for nanocluster functionalization. Alternatively, the addition of thiols serves to functionalize the nanoclusters. The resulting non-cytotoxic nanoclusters are taken up by cells and constitute a tuneable platform for biomedical applications including drug delivery.

  9. Solid phase extraction of uranium(VI) onto benzoylthiourea-anchored activated carbon

    Energy Technology Data Exchange (ETDEWEB)

    Zhao Yongsheng; Liu Chunxia; Feng Miao; Chen Zhen; Li Shuqiong; Tian Gan; Wang Li; Huang Jingbo [College of Chemistry, Sichuan University, 29 Wangjiang Lu, Chengdu, 610064, Sichuan (China); Li Shoujian, E-mail: sjli000616@scu.edu.cn [College of Chemistry, Sichuan University, 29 Wangjiang Lu, Chengdu, 610064, Sichuan (China)

    2010-04-15

    A new solid phase extractant selective for uranium(VI) based on benzoylthiourea anchored to activated carbon was developed via hydroxylation, amidation and reaction with benzoyl isothiocyanate in sequence. Fourier transform infrared spectroscopy and total element analysis proved that benzoylthiourea had been successfully grafted to the surface of the activated carbon, with a loading capacity of 1.2 mmol benzoylthiourea per gram of activated carbon. The parameters that affect the uranium(VI) sorption, such as contact time, solution pH, initial uranium(VI) concentration, adsorbent dose and temperature, have been investigated. Results have been analyzed by Langmuir and Freundlich isotherm; the former was more suitable to describe the sorption process. The maximum sorption capacity (82 mg/g) for uranium(VI) was obtained at experimental conditions. The rate constant for the uranium sorption by the as-synthesized extractant was 0.441 min{sup -1} from the first order rate equation. Thermodynamic parameters ({Delta}H{sup 0} = -46.2 kJ/mol; {Delta}S{sup 0} = -98.0 J/mol K; {Delta}G{sup 0} = -17.5 kJ/mol) showed the adsorption of an exothermic process and spontaneous nature, respectively. Additional studies indicated that the benzoylthiourea-anchored activated carbon (BT-AC) selectively sorbed uranyl ions in the presence of competing ions, Na{sup +}, Co{sup 2+}, Sr{sup 2+}, Cs{sup +} and La{sup 3+}.

  10. A reusable suture anchor for arthroscopy psychomotor skills training.

    Science.gov (United States)

    Tillett, Edward D; Rogers, Rainie; Nyland, John

    2003-03-01

    For residents to adequately develop the early arthroscopy psychomotor skills required to better learn how to manage the improvisational situations they will encounter during actual patient cases, they need to experience sufficient practice repetitions within a contextually relevant environment. Unfortunately, the cost of suture anchors can be a practice repetition-limiting factor in learning arthroscopic knot-tying techniques. We describe a technique for creating inexpensive reusable suture anchors and provide an example of their application to repair the anterior glenoid labrum during an arthroscopy psychomotor skills laboratory training session.

  11. Analysis of AISI 304 Tensile Strength as an Anchor Chain of Mooring System

    Science.gov (United States)

    Hamidah, I.; Wati, R.; Hamdani, R. A.

    2018-05-01

    The background of this research is the use of mild steel (i.e., St37) as anchor chain that works on the corrosive environment of seawater which is possible to decrease its tensile strength. The longer soaked in seawater, the more significant the lowering of its tensile strength. Anchor chain needs to be designed by considering its tensile strength and corrosion resistance, so it’s able to support mooring system well. The primary purpose of this research is obtaining the decreasing of stainless steel 304 (AISI 304) tensile strength which is corroded by seawater as anchor chain of the mooring system. It is also essential to obtain the lifetime of AISI304 and St37 as anchor chain with the same load, the corrosion rate of AISI 304, and St 37 in seawater. The method which was employed in this research is an experiment with four pieces of stainless steel AISI 304, and of St 37 corrosion testing samples, six pieces of stainless steel 304, and six pieces of St 37 for tensile testing samples. The result of this research shows that seawater caused stainless steel AISI 304 as anchor chain has decreased of tensile strength about 1.68 % during four weeks. Also, it indicates that AISI 304 as anchor chain has a lifetime about 130 times longer than St 37. Further, we found that the corrosion rate of stainless steel 304 in seawater is 0.2042 mpy in outstanding category, while the St 37 samples reached up to 27.0247 mpy ranked as fair category. This result recommends that AISI 304 more excellence than St 37 as anchor chain of the mooring system.

  12. NMR detection and characterization of sialylated glycoproteins and cell surface polysaccharides

    International Nuclear Information System (INIS)

    Barb, Adam W.; Freedberg, Darón I.; Battistel, Marcos D.; Prestegard, James H.

    2011-01-01

    Few solution NMR pulse sequences exist that are explicitly designed to characterize carbohydrates (glycans). This is despite the essential role carbohydrate motifs play in cell–cell communication, microbial pathogenesis, autoimmune disease progression and cancer metastasis, and despite that fact that glycans, often shed to extra-cellular fluids, can be diagnostic of disease. Here we present a suite of two dimensional coherence experiments to measure three different correlations (H3–C2, H3–C1, and C1–C2) on sialic acids, a group of nine-carbon carbohydrates found on eukaryotic cell surfaces that often play a key role in disease processes. The chemical shifts of the H3, C2, and C1 nuclei of sialic acids are sensitive to carbohydrate linkage, linkage conformation, and ionization state of the C1 carboxylate. The experiments reported include rigorous filter elements to enable detection and characterization of isotopically labeled sialic acids with high sensitivity in living cells and crude isolates with minimal interference from unwanted signals arising from the ∼1% 13 C-natural abundance of cellular metabolites. Application is illustrated with detection of sialic acids on living cells, in unpurified mixtures, and at the terminus of the N-glycan on the 55 kDa immunoglobulin G Fc.

  13. Rigid multipodal platforms for metal surfaces

    Directory of Open Access Journals (Sweden)

    Michal Valášek

    2016-03-01

    Full Text Available In this review the recent progress in molecular platforms that form rigid and well-defined contact to a metal surface are discussed. Most of the presented examples have at least three anchoring units in order to control the spatial arrangement of the protruding molecular subunit. Another interesting feature is the lateral orientation of these foot structures which, depending on the particular application, is equally important as the spatial arrangement of the molecules. The numerous approaches towards assembling and organizing functional molecules into specific architectures on metal substrates are reviewed here. Particular attention is paid to variations of both, the core structures and the anchoring groups. Furthermore, the analytical methods enabling the investigation of individual molecules as well as monomolecular layers of ordered platform structures are summarized. The presented multipodal platforms bearing several anchoring groups form considerably more stable molecule–metal contacts than corresponding monopodal analogues and exhibit an enlarged separation of the functional molecules due to the increased footprint, as well as restrict tilting of the functional termini with respect to the metal surface. These platforms are thus ideally suited to tune important properties of the molecule–metal interface. On a single-molecule level, several of these platforms enable the control over the arrangement of the protruding rod-type molecular structures (e.g., molecular wires, switches, rotors, sensors with respect to the surface of the substrate.

  14. Testing Anchoring effect in CV Data from Dichotomous Choice with a Follow-up Questioning

    Energy Technology Data Exchange (ETDEWEB)

    Shin, Young Cheol [Dae-Jin University, Pocheon (Korea)

    1998-09-01

    A questionnaire of dual bisected selection of CVM, which is an induced approach of intended payment, was suggested to overcome statistical inefficiency of a questionnaire of single bisected selection. In spite of several advantages of it, it is doubted that there would be an occurrence of anchoring effect, which is a psychological source of convenient starting point. Therefore, the general intended payment model, which can review the anchoring effect from CV questionnaire of dual bisected selection, was suggested and a mechanism that can review the anchoring effect from the model. This model is combining the dual variation model by Cameron and Quiggin (1994) with the results of bisected selective responses of a firstly presented particular amount as an explanatory variable of the second interior intended payment amount. If the sign of coefficient of the results of bisected selective responses of a firstly presented particular amount was negative and statistically significant, then it can be said that there is an anchoring effect. However, when there is uncertainty of occurrence of anchoring effect from the coefficient review, there is no need to worry about the anchoring effect if the average of estimated values of intended payment amount from two responses were different. As a result of applying this model and mechanism to CV materials on the improvement of water quality of the Han River, there is no need to worry about the anchoring effect. (author). 21 refs., 4 tabs.

  15. Evaluation of periodontal status adjacent to interproximal surfaces restored with composite resin, in comparison with non-restored interproximal surfaces

    Directory of Open Access Journals (Sweden)

    Elvia Christina Barros de Almeida

    2008-01-01

    Full Text Available Objective: The purpose of this study was to evaluate the periodontal status of interproximal surfaces restored with composite resin, in comparison with non-restored interproximal surfaces. Methods: In 65 patients, we analyzed 145 restored surfaces and 145 non-restored surfaces. Results: Most of the restored surfaces (54.3% showed radiographic alterations, which was shown to be higher among restorations with clinically detected proximal excess (56.8% x 52.8%; with lack of restorative material (64.5% x 51.4%; in restorations with proximal overhang (67.7% x 44.4%; in teeth with gingival inflammation?/bleeding (55.1% x 40.0% and in teeth with probing depth exceeding 3 mm (64.3% x 52.9%. However, there were no significant associations for these variables. Of the non-restored surfaces, 24.4% showed radiographic alterations, however there were no significant associations. Conclusion: The results showed a statistical significance for radiographic alterations in restored and non-restored surfaces.

  16. Development of a New Nondestructive Inspection Strategy for Corroded Multistrand Anchor Cables

    Science.gov (United States)

    2016-07-01

    parking structures, rock and soil anchors, houses, and many other structures. Figure 1 (left) and (middle) show a typical cable and multistrand anchor...primary tool to identify the ideal propagating modes, the inspection itself is typically carried out in the time domain. The selected tone- burst

  17. Bone-anchored hearing devices in children with unilateral conductive hearing loss: a patient-carer perspective.

    Science.gov (United States)

    Banga, Rupan; Doshi, Jayesh; Child, Anne; Pendleton, Elizabeth; Reid, Andrew; McDermott, Ann-Louise

    2013-09-01

    We sought to determine the outcome of implantation of a bone-anchored hearing device in children with unilateral conductive hearing loss. A retrospective case note analysis was used in a tertiary referral pediatric hospital to study 17 consecutive cases of pediatric patients with unilateral conductive hearing loss who were fitted with a bone-anchored hearing device between 2005 and 2010. The average age of the patients at the time of bone-anchored hearing device fitting was 10 years 6 months (range, 6 years 3 months to 16 years). Qualitative subjective outcome measures demonstrated benefit. The vast majority of patients reported improved social and physical functioning and improved quality of life. All 17 patients are currently using their bone-anchored hearing device on a daily basis after a follow-up of 6 months. This study has shown improved quality of life in children with unilateral hearing loss after implantation of their bone-anchored hearing device. There was a high degree of patient satisfaction and improvement in health status reported by children and/or carers. Bone-anchored hearing devices have an important role in the management of children with symptomatic unilateral hearing loss. Perhaps earlier consideration of a bone-anchored hearing device would be appropriate in selected cases.

  18. Monolayer Assemblies of a De Novo Designed 4-alpha-Helix Bundle Carboprotein and Its Sulfur Anchor Fragment on Au(111) Surfaces Addressed by Voltammetry and In Situ Scanning Tunneling Microscopy

    DEFF Research Database (Denmark)

    Brask, Jesper; Wackerbarth, Hainer; Jensen, Knud J.

    2003-01-01

    carboprotein without thiol anchor have been prepared and investigated for comparison. Cyclic and differential pulse voltammetry (DPV) of the proteins show desorption peaks around -750 mV (SCE), whereas the thiol anchor desorption peak is at -685 mV. The peaks are by far the highest for thiol monomeric 4-R...

  19. The detrimental consequences for seagrass of ineffective marine park management related to boat anchoring.

    Science.gov (United States)

    La Manna, G; Donno, Y; Sarà, G; Ceccherelli, G

    2015-01-15

    Posidonia oceanica (L.) Delile meadows are recognized as priority habitat for conservation by the EU Habitats Directive. The La Maddalena Archipelago National Park (Mediterranean Sea) P. oceanica meadow, the dominant coastal habitat of the area, is mostly threatened by boat anchoring. 12 years after the establishment of mooring fields and anchoring restrictions, a study was conducted to measure their effectiveness on the conservation of seagrass and the mitigation of anchoring damage. We found that: (i) the condition of P. oceanica was disturbed, both in the mooring fields and in control locations; (ii) mooring fields and anchoring restrictions did not show to be an efficient system for the protection of seagrass, in fact anchor scars increased after the tourist season; (iii) the mooring systems had an impact on the surrounding area of the meadow, probably due to their misuse. On the basis of these results, management recommendations for marine parks are proposed. Copyright © 2014 Elsevier Ltd. All rights reserved.

  20. Damage Mechanism in Counter Pairs Caused by Bionic Non-smoothed Surface

    Directory of Open Access Journals (Sweden)

    ZHANG Zhan-hui

    2016-08-01

    Full Text Available Four biomimetic non-smoothed surface specimens with different shapes were prepared by laser processing. Tests were conducted on MMU-5G wear and abrasion test machine to study the influencing rule of non-smoothed surfaces on counter pairs. The results show that the mass loss of the friction pair matching with the non-smoothed units is much greater than the ones matching with the smooth specimens. The pairs matching with different non-smoothed units suffer differently. The non-smoothed surface protruding zone exerts micro cutting on counter pairs. The striation causes the greatest mass loss of the pairs than the other non-smoothed units, which almost doubles the damage of the grid ones suffering the least. The difference in pairs damage is attributed to the different mechanism of undertaking the load in the process of wear. The damage can be alleviated effectively by changing the shapes of the units without increasing or decreasing the area ratio of the non-smoothed units.

  1. The Holding Power of Anchors

    Indian Academy of Sciences (India)

    as the chain begins to drag along the ground; and it also serves, by lying flat on the ground, to keep the palm set at the correct angle as it buries itself. In stockless anchors there are two digging blades set on opposite sides of the shank, and hinged to it by a horizontal hinge which allows them to set themselves at the correct.

  2. Influence of polymer size, liposomal composition, surface charge, and temperature on the permeability of pH-sensitive liposomes containing lipid-anchored poly(2-ethylacrylic acid

    Directory of Open Access Journals (Sweden)

    Lu T

    2012-09-01

    Full Text Available Tingli Lu,1 Zhao Wang,2 Yufan Ma,1 Yang Zhang,2 Tao Chen1,21Key Laboratory for Space Bioscience and Biotechnology, School of Life Science, Northwestern Polytechnical University, 2Liposome Research Centre, Xi'an, ChinaBackground: Liposomes containing pH-sensitive polymers are promising candidates for the treatment of tumors and localized infection. This study aimed to identify parameters influencing the extent of contents release from poly(ethylacrylic acid (PEAA vesicles, focusing on the effects of polymer size, lipid composition, vesicle surface charge, and temperature.Methods: Anchored lipid pH-sensitive PEAA was synthesized using PEAA with a molecular weight of 8.4 kDa. PEAA vesicles were prepared by insertion of the lipid-anchored PEAA into preformed large unilamellar vesicles. The preformed liposomes were manipulated by varying the phosphocholine and cholesterol content, and by adding negative or positive charges to the liposomes. A calcein release assay was used to evaluate the effects of polymer size, liposome composition, surface charge, and temperature on liposomal permeability.Results: The release efficiency of the calcein-entrapped vesicles was found to be dependent on the PEAA polymer size. PEAA vesicles containing a phosphatidylcholine to cholesterol ratio of 60:40 (mol/mol released more than 80% of their calcein content when the molecular weight of PEAA was larger than 8.4 kDa. Therefore, the same-sized polymer of 8.4 kDa was used for the rest of study. The calcein release potential was found to decrease as the percentage of cholesterol increased and with an increase in the phosphocholine acyl chain length (DMPC . DPPC . DSPC. Negatively charged and neutral vesicles released similar amounts of calcein, whereas positively charged liposomes released a significant amount of their contents. pH-sensitive release was dependent on temperature. Dramatic content release was observed at higher temperatures.Conclusion: The observed

  3. Return to football and long-term clinical outcomes after thumb ulnar collateral ligament suture anchor repair in collegiate athletes.

    Science.gov (United States)

    Werner, Brian C; Hadeed, Michael M; Lyons, Matthew L; Gluck, Joshua S; Diduch, David R; Chhabra, A Bobby

    2014-10-01

    To evaluate return to play after complete thumb ulnar collateral ligament (UCL) injury treated with suture anchor repair for both skill position and non-skill position collegiate football athletes and report minimum 2-year clinical outcomes in this population. For this retrospective study, inclusion criteria were complete rupture of the thumb UCL and suture anchor repair in a collegiate football athlete performed by a single surgeon who used an identical technique for all patients. Data collection included chart review, determination of return to play, and Quick Disabilities of the Arm, Shoulder, and Hand (QuickDASH) outcomes. A total of 18 collegiate football athletes were identified, all of whom were evaluated for follow-up by telephone, e-mail, or regular mail at an average 6-year follow-up. Nine were skill position players; the remaining 9 played in nonskill positions. All players returned to at least the same level of play. The average QuickDASH score for the entire cohort was 1 out of 100; QuickDASH work score, 0 out of 100; and sport score, 1 out of 100. Average time to surgery for skill position players was 12 days compared with 43 for non-skill position players. Average return to play for skill position players was 7 weeks postoperatively compared with 4 weeks for non-skill position players. There was no difference in average QuickDASH overall scores or subgroup scores between cohorts. Collegiate football athletes treated for thumb UCL injuries with suture anchor repair had quick return to play, reliable return to the same level of activity, and excellent long-term clinical outcomes. Skill position players had surgery sooner after injury and returned to play later than non-skill position players, with no differences in final level of play or clinical outcomes. Management of thumb UCL injuries in collegiate football athletes can be safely and effectively tailored according to the demands of the player's football position. Therapeutic IV. Copyright © 2014

  4. Anchoring effect on first passage process in Taiwan financial market

    Science.gov (United States)

    Liu, Hsing; Liao, Chi-Yo; Ko, Jing-Yuan; Lih, Jiann-Shing

    2017-07-01

    Empirical analysis of the price fluctuations of financial markets has received extensive attention because a substantial amount of financial market data has been collected and because of advances in data-mining techniques. Price fluctuation trends can help investors to make informed trading decisions, but such decisions may also be affected by a psychological factors-the anchoring effect. This study explores the intraday price time series of Taiwan futures, and applies diffusion model and quantitative methods to analyze the relationship between the anchoring effect and price fluctuations during first passage process. Our results indicate that power-law scaling and anomalous diffusion for stock price fluctuations are related to the anchoring effect. Moreover, microscopic price fluctuations before switching point in first passage process correspond with long-term price fluctuations of Taiwan's stock market. We find that microscopic trends could provide useful information for understanding macroscopic trends in stock markets.

  5. Career Anchors of United States Air Force Information Systems Workers: A Turnover Predictor

    National Research Council Canada - National Science Library

    Wynne, Lee

    2002-01-01

    ...) and the work of Schein (1987) to measure the career anchors, job satisfaction, and turnover intention of AF IS workers to determine if those whose job type and career anchor match report higher satisfaction and lower turnover...

  6. Bulk-mediated surface diffusion: non-Markovian desorption dynamics

    International Nuclear Information System (INIS)

    Revelli, Jorge A; Budde, Carlos E; Prato, Domingo; Wio, Horacio S

    2005-01-01

    Here we analyse the dynamics of adsorbed molecules within the bulk-mediated surface diffusion framework, when the particle's desorption mechanism is characterized by a non-Markovian process, while the particle's adsorption as well as its motion in the bulk is governed by Markovian dynamics. We study the diffusion of particles in both semi-infinite and finite cubic lattices, analysing the conditional probability to find the system on the reference absorptive plane as well as the surface dispersion as functions of time. The results are compared with known Markovian cases showing the differences that can be exploited to distinguish between Markovian and non-Markovian desorption mechanisms in experimental situations

  7. Comparison between suture anchor and transosseous suture for the modified-Broström procedure.

    Science.gov (United States)

    Cho, Byung-Ki; Kim, Yong-Min; Kim, Dong-Soo; Choi, Eui-Sung; Shon, Hyun-Chul; Park, Kyoung-Jin

    2012-06-01

    This prospective, randomized study was conducted to compare clinical outcomes of the modified Broström procedure using suture anchor or transosseous suture technique for chronic ankle instability. Forty patients were followed for more than 2 years after modified Broström procedure. Twenty procedures using a suture anchor and 20 procedures using a transosseous suture were performed by one surgeon. The clinical evaluation consisted of the Karlsson scale and the Sefton grading system. Talar tilt and anterior talar translation were measured on anterior and varus stress radiographs. The Karlsson scale had improved significantly to 90.8 points in the suture anchor group, and to 89.2 points in the transosseous suture group. According to Sefton grading system, 18 patients (90%) in suture anchor group and 17 patients (85%) in transosseous suture group achieved satisfactory results. The talar tilt angle and anterior talar translation improved significantly to 5.9 degrees and 4.2 mm in suture anchor group, and to 5.4 degrees and 4.1 mm in transosseous suture group, respectively. No significant differences existed in clinical and functional outcomes between the two techniques for ligament reattachment. Both modified Broström procedures using the suture anchor and transosseous suture seem to be effective treatment methods for chronic lateral ankle instability.

  8. PI3KC2{alpha}, a class II PI3K, is required for dynamin-independent internalization pathways

    DEFF Research Database (Denmark)

    Krag, Claudia; Malmberg, Emily Kim; Salcini, Anna Elisabetta

    2010-01-01

    as fluid-phase endocytosis. Our data suggest a general role for PI3KC2a in regulating physiologically relevant dynamin-independent internalization pathways by recruiting early endosome antigen 1 (EEA1) to vesicular compartments, a step required for the intracellular trafficking of vesicles generated...... screen using a cell line expressing a diphtheria toxin receptor (DTR, officially known as HBEGF) anchored to GPI (DTR-GPI), which internalizes diphtheria toxin (DT, officially known as DTX) in a dynamin-independent manner, identified PI3KC2a, a class II phosphoinositide 3-kinase (PI3K), as a specific...... regulator of dynamin-independent DT internalization. We found that the internalization of several proteins that enter the cell through dynamin-independent pathways led to a relocalization of PI3KC2a to cargo-positive vesicles. Furthermore, downregulation of PI3KC2a impaired internalization of CD59 as well...

  9. Site-selective growth of surface-anchored metal-organic frameworks on self-assembled monolayer patterns prepared by AFM nanografting

    Directory of Open Access Journals (Sweden)

    Tatjana Ladnorg

    2013-10-01

    Full Text Available Surface anchored metal-organic frameworks, SURMOFs, are highly porous materials, which can be grown on modified substrates as highly oriented, crystalline coatings by a quasi-epitaxial layer-by-layer method (liquid-phase epitaxy, or LPE. The chemical termination of the supporting substrate is crucial, because the most convenient method for substrate modification is the formation of a suitable self-assembled monolayer. The choice of a particular SAM also allows for control over the orientation of the SURMOF. Here, we demonstrate for the first time the site-selective growth of the SURMOF HKUST-1 on thiol-based self-assembled monolayers patterned by the nanografting technique, with an atomic force microscope as a structuring tool. Two different approaches were applied: The first one is based on 3-mercaptopropionic acid molecules which are grafted in a 1-decanethiolate SAM, which serves as a matrix for this nanolithography. The second approach uses 16-mercaptohexadecanoic acid, which is grafted in a matrix of an 1-octadecanethiolate SAM. In both cases a site-selective growth of the SURMOF is observed. In the latter case the roughness of the HKUST-1 is found to be significantly higher than for the 1-mercaptopropionic acid. The successful grafting process was verified by time-of-flight secondary ion mass spectrometry and atomic force microscopy. The SURMOF structures grown via LPE were investigated and characterized by atomic force microscopy and Fourier-transform infrared microscopy.

  10. Site-selective growth of surface-anchored metal-organic frameworks on self-assembled monolayer patterns prepared by AFM nanografting

    Science.gov (United States)

    Ladnorg, Tatjana; Welle, Alexander; Heißler, Stefan; Wöll, Christof

    2013-01-01

    Summary Surface anchored metal-organic frameworks, SURMOFs, are highly porous materials, which can be grown on modified substrates as highly oriented, crystalline coatings by a quasi-epitaxial layer-by-layer method (liquid-phase epitaxy, or LPE). The chemical termination of the supporting substrate is crucial, because the most convenient method for substrate modification is the formation of a suitable self-assembled monolayer. The choice of a particular SAM also allows for control over the orientation of the SURMOF. Here, we demonstrate for the first time the site-selective growth of the SURMOF HKUST-1 on thiol-based self-assembled monolayers patterned by the nanografting technique, with an atomic force microscope as a structuring tool. Two different approaches were applied: The first one is based on 3-mercaptopropionic acid molecules which are grafted in a 1-decanethiolate SAM, which serves as a matrix for this nanolithography. The second approach uses 16-mercaptohexadecanoic acid, which is grafted in a matrix of an 1-octadecanethiolate SAM. In both cases a site-selective growth of the SURMOF is observed. In the latter case the roughness of the HKUST-1 is found to be significantly higher than for the 1-mercaptopropionic acid. The successful grafting process was verified by time-of-flight secondary ion mass spectrometry and atomic force microscopy. The SURMOF structures grown via LPE were investigated and characterized by atomic force microscopy and Fourier-transform infrared microscopy. PMID:24205458

  11. Facile solid-state synthesis of highly dispersed Cu nanospheres anchored on coal-based activated carbons as an efficient heterogeneous catalyst for the reduction of 4-nitrophenol

    Science.gov (United States)

    Wang, Shan; Gao, Shasha; Tang, Yakun; Wang, Lei; Jia, Dianzeng; Liu, Lang

    2018-04-01

    Coal-based activated carbons (AC) were acted as the support, Cu/AC catalysts were synthesized by a facile solid-state reaction combined with subsequent heat treatment. In Cu/AC composites, highly dispersed Cu nanospheres were anchored on AC. The catalytic activity for 4-nitrophenol (4-NP) was investigated, the effects of activation temperature and copper loading on the catalytic performance were studied. The catalysts exhibited very high catalytic activity and moderate chemical stability due to the unique characteristics of the particle-assembled nanostructures, the high surface area and the porous structure of coal-based AC and the good dispersion of metal particles. Design and preparation of non-noble metal composite catalysts provide a new direction for improving the added value of coal.

  12. Bone suture anchor fixation in the lower extremity: a review of insertion principles and a comparative biomechanical evaluation.

    Science.gov (United States)

    Scranton, Pierce E; Lawhon, S Michael; McDermott, John E

    2005-07-01

    Suture anchors have been developed for the fixation of ligaments, capsules, or tendons to bone. These devices have led to improved fixation, smaller incisions, earlier limb mobility, and improved outcomes. They were originally developed for use in shoulder reconstructions but are now used in almost all extremities. In the lower leg they are used in the tibia, the talus, the calcaneus, tarsal bones, and phalanges. Nevertheless, techniques for insertion and mechanisms of failure are not well described. Five suture anchors were studied to determine the pullout strength in four distal cadaver femurs and four proximal cadaver tibias from 55- and 62-year-old males. Eight hundred ninety Newton line was used, testing the anchors to failure with an Instron testing device (Instron, Norwood, MA). The anchor devices were inserted randomly and tested blindly (12 tests per anchor device, 60 tests in all). Two anchors in each group tested failed at low loads. Both types of plastic anchors had failures at the eyelet. Average pullout strength varied from 85.4 to 185.6 N. Insertion techniques are specific for each device, and they must be followed for optimal fixation. In this study, in all five groups of anchors tested two of the 12 anchors in each group failed with minimal force. On the basis of this finding we recommend that, if suture anchor fixation is necessary, at least two anchors should be used. Since there appears to be a percentage of failure in all devices, the second anchor can serve as a backup. It is imperative that surgeons be familiar with the insertion techniques of each device before use.

  13. On the dielectric and optical properties of surface-anchored metal-organic frameworks: A study on epitaxially grown thin films

    Science.gov (United States)

    Redel, Engelbert; Wang, Zhengbang; Walheim, Stefan; Liu, Jinxuan; Gliemann, Hartmut; Wöll, Christof

    2013-08-01

    We determine the optical constants of two highly porous, crystalline metal-organic frameworks (MOFs). Since it is problematic to determine the optical constants for the standard powder modification of these porous solids, we instead use surface-anchored metal-organic frameworks (SURMOFs). These MOF thin films are grown using liquid phase epitaxy (LPE) on modified silicon substrates. The produced SURMOF thin films exhibit good optical properties; these porous coatings are smooth as well as crack-free, they do not scatter visible light, and they have a homogenous interference color over the entire sample. Therefore, spectroscopic ellipsometry (SE) can be used in a straightforward fashion to determine the corresponding SURMOF optical properties. After careful removal of the solvent molecules used in the fabrication process as well as the residual water adsorbed in the voids of this highly porous solid, we determine an optical constant of n = 1.39 at a wavelength of 750 nm for HKUST-1 (stands for Hong Kong University of Science and Technology-1; and was first discovered there) or [Cu3(BTC)2]. After exposing these SURMOF thin films to moisture/EtOH atmosphere, the refractive index (n) increases to n = 1.55-1.6. This dependence of the optical properties on water/EtOH adsorption demonstrates the potential of such SURMOF materials for optical sensing.

  14. Anhydride-functional silane immobilized onto titanium surfaces induces osteoblast cell differentiation and reduces bacterial adhesion and biofilm formation

    International Nuclear Information System (INIS)

    Godoy-Gallardo, Maria; Guillem-Marti, Jordi; Sevilla, Pablo; Manero, José M.; Gil, Francisco J.

    2016-01-01

    Bacterial infection in dental implants along with osseointegration failure usually leads to loss of the device. Bioactive molecules with antibacterial properties can be attached to titanium surfaces with anchoring molecules such as silanes, preventing biofilm formation and improving osseointegration. Properties of silanes as molecular binders have been thoroughly studied, but research on the biological effects of these coatings is scarce. The aim of the present study was to determine the in vitro cell response and antibacterial effects of triethoxysilypropyl succinic anhydride (TESPSA) silane anchored on titanium surfaces. X-ray photoelectron spectroscopy confirmed a successful silanization. The silanized surfaces showed no cytotoxic effects. Gene expression analyses of Sarcoma Osteogenic (SaOS-2) osteoblast-like cells cultured on TESPSA silanized surfaces reported a remarkable increase of biochemical markers related to induction of osteoblastic cell differentiation. A manifest decrease of bacterial adhesion and biofilm formation at early stages was observed on treated substrates, while favoring cell adhesion and spreading in bacteria–cell co-cultures. Surfaces treated with TESPSA could enhance a biological sealing on implant surfaces against bacteria colonization of underlying tissues. Furthermore, it can be an effective anchoring platform of biomolecules on titanium surfaces with improved osteoblastic differentiation and antibacterial properties. - Highlights: • TESPSA silane induces osteoblast differentiation. • TESPSA reduces bacterial adhesion and biofilm formation. • TESPSA is a promising anchoring platform of biomolecules onto titanium.

  15. Anhydride-functional silane immobilized onto titanium surfaces induces osteoblast cell differentiation and reduces bacterial adhesion and biofilm formation

    Energy Technology Data Exchange (ETDEWEB)

    Godoy-Gallardo, Maria, E-mail: maria.godoy.gallardo@upc.edu [Biomaterials, Biomechanics and Tissue Engineering Group, Department of Materials Science and Metallurgy, Technical University of Catalonia (UPC), ETSEIB, Av. Diagonal 647, 08028 Barcelona (Spain); Centre for Research in NanoEngineering (CRNE) — UPC, C/ Pascual i Vila 15, 08028 Barcelona (Spain); Guillem-Marti, Jordi, E-mail: jordi.guillem.marti@upc.edu [Biomaterials, Biomechanics and Tissue Engineering Group, Department of Materials Science and Metallurgy, Technical University of Catalonia (UPC), ETSEIB, Av. Diagonal 647, 08028 Barcelona (Spain); Centre for Research in NanoEngineering (CRNE) — UPC, C/ Pascual i Vila 15, 08028 Barcelona (Spain); Sevilla, Pablo, E-mail: psevilla@euss.es [Department of Mechanics, Escola Universitària Salesiana de Sarrià (EUSS), C/ Passeig de Sant Bosco, 42, 08017 Barcelona (Spain); Manero, José M., E-mail: jose.maria.manero@upc.edu [Biomaterials, Biomechanics and Tissue Engineering Group, Department of Materials Science and Metallurgy, Technical University of Catalonia (UPC), ETSEIB, Av. Diagonal 647, 08028 Barcelona (Spain); Centre for Research in NanoEngineering (CRNE) — UPC, C/ Pascual i Vila 15, 08028 Barcelona (Spain); Gil, Francisco J., E-mail: francesc.xavier.gil@upc.edu [Biomaterials, Biomechanics and Tissue Engineering Group, Department of Materials Science and Metallurgy, Technical University of Catalonia (UPC), ETSEIB, Av. Diagonal 647, 08028 Barcelona (Spain); Centre for Research in NanoEngineering (CRNE) — UPC, C/ Pascual i Vila 15, 08028 Barcelona (Spain); and others

    2016-02-01

    Bacterial infection in dental implants along with osseointegration failure usually leads to loss of the device. Bioactive molecules with antibacterial properties can be attached to titanium surfaces with anchoring molecules such as silanes, preventing biofilm formation and improving osseointegration. Properties of silanes as molecular binders have been thoroughly studied, but research on the biological effects of these coatings is scarce. The aim of the present study was to determine the in vitro cell response and antibacterial effects of triethoxysilypropyl succinic anhydride (TESPSA) silane anchored on titanium surfaces. X-ray photoelectron spectroscopy confirmed a successful silanization. The silanized surfaces showed no cytotoxic effects. Gene expression analyses of Sarcoma Osteogenic (SaOS-2) osteoblast-like cells cultured on TESPSA silanized surfaces reported a remarkable increase of biochemical markers related to induction of osteoblastic cell differentiation. A manifest decrease of bacterial adhesion and biofilm formation at early stages was observed on treated substrates, while favoring cell adhesion and spreading in bacteria–cell co-cultures. Surfaces treated with TESPSA could enhance a biological sealing on implant surfaces against bacteria colonization of underlying tissues. Furthermore, it can be an effective anchoring platform of biomolecules on titanium surfaces with improved osteoblastic differentiation and antibacterial properties. - Highlights: • TESPSA silane induces osteoblast differentiation. • TESPSA reduces bacterial adhesion and biofilm formation. • TESPSA is a promising anchoring platform of biomolecules onto titanium.

  16. A group of 20 stone anchors from the waters of Dwarka, on the Gujarat Coast, India

    Digital Repository Service at National Institute of Oceanography (India)

    Gaur, A.S; Sundaresh; Tripati, S.; Gudigar, P.; Vora, K.H.; Bandodkar, S.N.

    A large number of stone anchors were discovered in a water depth of 10-14 m off Dwarka during the 1998-99 season. The seabed near the anchors consists of a ledge with an average height of 1 m. Several anchors were found trapped between the rocks...

  17. Membrane curvature enables N-Ras lipid anchor sorting to liquid-ordered membrane phases

    DEFF Research Database (Denmark)

    Larsen, Jannik Bruun; Jensen, Martin Borch; Bhatia, Vikram Kjøller

    2015-01-01

    Trafficking and sorting of membrane-anchored Ras GTPases are regulated by partitioning between distinct membrane domains. Here, in vitro experiments and microscopic molecular theory reveal membrane curvature as a new modulator of N-Ras lipid anchor and palmitoyl chain partitioning. Membrane...

  18. Talar anchor placement for modified Brostrom lateral ankle stabilization procedure.

    Science.gov (United States)

    Angirasa, Arush K; Barrett, Michael J

    2008-01-01

    The modified Brostrom procedure has been a proven procedure with excellent utility in the treatment of lateral ankle instability within limitation. Multiple variations of the original technique have been described in the literature to date. Included in these variations are differences in anchor placement, suture technique, or both. In this research study, we propose placing a bone screw anchor into the lateral shoulder of the talus rather than the typical placement at the lateral malleolus for anatomic reconstruction of the lateral ankle ligaments.

  19. Career Anchors: A New Concept in Career Development for the Professional Educator.

    Science.gov (United States)

    DeLong, Thomas J.

    Created by Dr. Edgar Schein of the Massachusetts Institute of Technology (MIT), the career anchor model suggests that certain motivational/talent/value drives, formed through work experience, function to guide and constrain entire careers; and that such anchors are the source of stability that permits growth and change in other areas. The concept…

  20. The Double-Anchoring Theory of Lightness Perception: A Comment on Bressan (2006)

    Science.gov (United States)

    Howe, Piers D. L.; Sagreiya, Hersh; Curtis, Dwight L.; Zheng, Chengjie; Livingstone, Margaret S.

    2007-01-01

    Comments on an article by Bressan. Recently, a double-anchoring theory (DAT) of lightness perception was proposed (P. Bressan, 2006), which offers explanations for all the data explained by the original anchoring theory (A. Gilchrist et al., 1999), as well as a number of additional lightness phenomena. Consequently, DAT can account for an…