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Structural comparison and evolutionary relationships between ceruloplasmin, hephaestin and blood coagulation factor VIII. Acta Crystallogr A Found Adv 2019. [DOI: 10.1107/s2053273319093641] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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2
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Structural comparison of two mammalian multicopper oxidases, hephaestin and ceruloplasmin. Acta Crystallogr A Found Adv 2019. [DOI: 10.1107/s2053273319094191] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
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3
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Human epidermal growth factor receptor (HER-1:HER-3) Fc-mediated heterodimer has broad antiproliferative activity in vitro and in human tumor xenografts. Mol Cancer Ther 2008; 7:3223-36. [PMID: 18852126 DOI: 10.1158/1535-7163.mct-07-2151] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
All four members of the human epidermal growth factor (EGF) receptor (HER) family are implicated in human cancers. Although efficacious in a subset of patients, resistance to single-targeted anti-HER therapy [i.e., cetuximab (Erbitux) and trastuzumab (Herceptin)] is often associated with coexpression of other HER family members. This may be overcome by a HER ligand binding molecule that sequesters multiple EGF-like ligands, preventing ligand-dependent receptor activation. Toward this end, we have combined the HER-1/EGFR and HER-3 ligand binding domains, dimerized with fusion of an Fc fragment of human IgG1. This resulted in a mixture of HER-1/Fc homodimer (HFD100), HER-3/Fc homodimer (HFD300), and HER-1/Fc:HER-3/Fc heterodimer (RB200), also termed Hermodulins. The purified first-generation RB200 bound EGF and neuregulin 1 (NRG1)-beta1 ligands, determined by cross-linking and direct binding studies. The binding affinity for both was approximately 10 nmol/L by dissociation-enhanced lanthanide fluorescence immunoassay using europium (Eu)-labeled ligands. Competition studies with RB200 using Eu-EGF or Eu-NRG1-beta1 revealed that RB200 bound HER-1 ligands, including transforming growth factor-alpha and heparin-binding EGF, and HER-3 ligands NRG1-alpha and NRG1-beta3. RB200 inhibited EGF- and NRG1-beta1-stimulated tyrosine phosphorylation of HER family proteins, proliferation of a diverse range of tumor cells in monolayer cell growth assays, tumor cell proliferation as a single agent and in synergy with tyrosine kinase inhibitors, lysophosphatidic acid-stimulated cell proliferation, and tumor growth in two human tumor xenograft nude mouse models. Taken together, the data reveal that RB200 has the potential to sequester multiple HER ligands and interfere with signaling by HER-1, HER-2, and HER-3.
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Erratum: Development, inheritance, and linkage-group assignment of 60 novel microsatellite markers for the gray, short-tailed opossum Monodelphis domestica. Genome 2006. [DOI: 10.1139/g06-012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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5
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Development, inheritance, and linkage-group assignment of 60 novel microsatellite markers for the gray, short-tailed opossum Monodelphis domestica. Genome 2005; 48:1019-27. [PMID: 16391671 DOI: 10.1139/g05-059] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Short-tandem-repeat (SSR) or microsatellite polymorphisms are some of the most extensively employed genetic markers in contemporary linkage mapping studies. To date, only a limited number of microsatellites have been isolated in the gray, short-tailed opossum Monodelphis domestica, a South American marsupial widely used for comparative biological and biomedical research. To increase the number of potentially useful mapping markers, we screened 2 microsatellite-enriched genomic libraries containing alternatively (CA)n or (GA)n repeats. A total of 184 clones were sequenced, from which 60 polymorphic microsatellite markers were successfully optimized. The efficiency of this enrichment protocol for M. domestica microsatellite isolation is discussed, and suggestions to improve the outcome are made. All 60 loci showed high allelic diversity, with allele numbers ranging from 2 to 10 in a subset of 33 unrelated animals. Normal Mendelian inheritance was confirmed for all loci by analyzing allelic segregation in 5 two-generation families. One microsatellite appeared to be X linked, and null alleles were found in 5 others. Two-point linkage analyses were implemented using the data on the 5 families, leading to the assignment of 59 of these loci to the existing linkage groups. The 60 novel microsatellites developed in this study will contribute significantly to the M. domestica linkage map, and further QTL mapping studies.Key words: Monodelphis domestica, marsupial, microsatellite, enriched libraries, genetic linkage analysis.
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Structure of the hybrid cluster protein (HCP) from Desulfovibrio desulfuricans ATCC 27774 containing molecules in the oxidized and reduced states. ACTA CRYSTALLOGRAPHICA SECTION D: BIOLOGICAL CRYSTALLOGRAPHY 2003; 59:2065-71. [PMID: 14646063 DOI: 10.1107/s0907444903025861] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/12/2003] [Accepted: 11/04/2003] [Indexed: 11/10/2022]
Abstract
The hybrid cluster protein (HCP) from the sulfate-reducing bacteria Desulfovibrio desulfuricans ATCC 27774 has been isolated and crystallized anaerobically. The protein sample used in the crystallization studies was several months old, having been stored at 193 K, and initial crystal structure studies were unable to fully resolve details of the hybrid cluster despite the use of high-resolution data to 1.25 A collected at the ESRF, Grenoble, France. Full elucidation of the structure has only become possible with the complete knowledge of the as-isolated and fully reduced crystal structures. The analysis clarifies the significant movements in the position of the Fe atom linked to the persulfide moiety in the oxidized as-isolated protein and the S atom of the persulfide itself as the protein is reduced. The structures of the as-isolated and reduced states are discussed in terms of the putative function of the HCP proteins.
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Reduced hybrid cluster proteins (HCP) from Desulfovibrio desulfuricans ATCC 27774 and Desulfovibrio vulgaris (Hildenborough): X-ray structures at high resolution using synchrotron radiation. J Biol Inorg Chem 2003; 8:540-548. [PMID: 12764602 DOI: 10.1007/s00775-003-0443-x] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2002] [Accepted: 01/14/2003] [Indexed: 10/18/2022]
Abstract
The hybrid cluster proteins from the sulfate reducing bacteria Desulfovibrio desulfuricans ATCC 27774 ( Dd) and Desulfovibrio vulgaris strain Hildenborough ( Dv) have been isolated and crystallized anaerobically. In each case, the protein has been reduced with dithionite and the crystal structure of the reduced form elucidated using X-ray synchrotron radiation techniques at 1.25 A and 1.55 A resolution for Dd and Dv, respectively. Although the overall structures of the proteins are unchanged upon reduction, there are significant changes at the hybrid cluster centres. These include significant movements in the position of the iron atom linked to the persulfide moiety in the oxidized as-isolated proteins and the sulfur atom of the persulfide itself. The nature of these changes is described and the implications with respect to the function of hybrid cluster proteins are discussed.
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The nature of the di-iron site in the bacterioferritin from Desulfovibrio desulfuricans. Nat Struct Mol Biol 2003; 10:285-90. [PMID: 12627224 DOI: 10.1038/nsb909] [Citation(s) in RCA: 96] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2002] [Accepted: 02/03/2003] [Indexed: 11/08/2022]
Abstract
The first crystal structure of a native di-iron center in an iron-storage protein (bacterio)ferritin is reported. The protein, isolated from the anaerobic bacterium Desulfovibrio desulfuricans, has the unique property of having Fe-coproporphyrin III as its heme cofactor. The three-dimensional structure of this bacterioferritin was determined in three distinct catalytic/redox states by X-ray crystallography (at 1.95, 2.05 and 2.35 A resolution), corresponding to different intermediates of the di-iron ferroxidase site. Conformational changes associated with these intermediates support the idea of a route for iron entry into the protein shell through a pore that passes through the di-iron center. Molecular surface and electrostatic potential calculations also suggest the presence of another ion channel, distant from the channels at the three- and four-fold axes proposed as points of entry for the iron atoms.
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Hybrid cluster protein (HCP) from Desulfovibrio vulgarisand Desulfovibrio desulfuricans: aerobic, anaerobic and reduced structural studies. Acta Crystallogr A 2002. [DOI: 10.1107/s0108767302089699] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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10
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Abstract
Alkaline phosphatases are non-specific phosphomonoesterases that are distributed widely in species ranging from bacteria to man. This study has concentrated on the tissue-nonspecific alkaline phosphatase from arctic shrimps (shrimp alkaline phosphatase, SAP). Originating from a cold-active species, SAP is thermolabile and is used widely in vitro, e.g. to dephosphorylate DNA or dNTPs, since it can be inactivated by a short rise in temperature. Since alkaline phosphatases are zinc-containing enzymes, a multiwavelength anomalous dispersion (MAD) experiment was performed on the zinc K edge, which led to the determination of the structure to a resolution of 1.9 A. Anomalous data clearly showed the presence of a zinc triad in the active site, whereas alkaline phosphatases usually contain two zinc and one magnesium ion per monomer. SAP shares the core, an extended beta-sheet flanked by alpha-helices, and a metal triad with the currently known alkaline phosphatase structures (Escherichia coli structures and a human placental structure). Although SAP lacks some features specific for the mammalian enzyme, their backbones are very similar and may therefore be typical for other higher organisms. Furthermore, SAP possesses a striking feature that the other structures lack: surface potential representations show that the enzyme's net charge of -80 is distributed such that the surface is predominantly negatively charged, except for the positively charged active site. The negatively charged substrate must therefore be directed strongly towards the active site. It is generally accepted that optimization of the electrostatics is one of the characteristics related to cold-adaptation. SAP demonstrates this principle very clearly.
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11
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Hybrid cluster proteins (HCPs) from Desulfovibrio desulfuricans ATCC 27774 and Desulfovibrio vulgaris (Hildenborough): X-ray structures at 1.25 A resolution using synchrotron radiation. J Biol Inorg Chem 2002; 7:514-25. [PMID: 11941509 DOI: 10.1007/s00775-001-0326-y] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2001] [Accepted: 11/28/2001] [Indexed: 11/24/2022]
Abstract
The structures of the hybrid cluster proteins (HCPs) from the sulfate-reducing bacteria Desulfovibrio desulfuricans (ATCC 27774) and Desulfovibrio vulgaris (Hildenborough) have been elucidated at a resolution of 1.25 A using X-ray synchrotron radiation techniques. In the case of the D. desulfuricans protein, protein isolation, purification, crystallization and X-ray data collection were carried out under strict anaerobic conditions, whereas for the D. vulgaris protein the conditions were aerobic. However, both structures are essentially the same, comprising three domains and two iron-sulfur centres. One of these centres situated near the exterior of the molecules in domain 1 is a cubane [4Fe-4S] cluster, whereas the other, located at the interface of the three domains, contains the unusual four-iron cluster initially found in the D. vulgaris protein. Details of the structures and the associated EPR spectroscopy of the D. desulfuricans protein are reported herein. These structures show that the nature of the hybrid cluster, containing both oxygen and sulfur bridges, is independent of the presence of oxygen in the isolation and crystallization procedure and also does not vary significantly with changes in the oxidation state. The structures and amino acid sequences of the HCP are compared with the recently elucidated structure of the catalytic subunit of a carbon monoxide dehydrogenase from Carboxydothermus hydrogenoformans and related dehydrogenases. Electronic supplementary material to this paper can be obtained by using the Springer Link server located at http://dx.doi.org/10.1007/s00775-001-0326-y.
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12
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Structural determination of Bacterioferritin from Desulfovibrio DesulfuricansATCC 27774. Acta Crystallogr A 2000. [DOI: 10.1107/s0108767300025952] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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13
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Abstract
Crystal structures for both native and recombinant forms of yeast fumarase from Saccharomyces cerevisiae have been completed to moderate resolution by two separate laboratories. The recombinant form was obtained by the construction of an expression plasmid for Escherichia coli. Despite a high level of amino acid sequence similarity, purification of the eukaryotic enzyme from the wild-type prokaryotic enzyme was feasible. The crystal structure of the native form, NY-fumarase, encompasses residues R22 through M484, while the recombinant form, RY-fumarase, consists of residues S27 through L485. Both crystal structures lack the N-terminal translocation segment. Each subunit of the homo-tetrameric protein has three domains. The active site is formed by segments from each of three polypeptide chains. The results of these studies on the eukaryotic proteins are unique, since the recombinant form was done in the absence of dicarboxylic acid and has an unoccupied active site. As a comparison, native fumarase was crystallized in the presence of the competitive inhibitor, meso-tartrate. Meso-tartrate occupies a position close to that of the bound citrate molecule found in the active site of the E. coli enzyme. This inhibitor participates in hydrogen bonding to an active-site water molecule. The independent determination of the two structures provides further evidence that an active-site water molecule may play an active role in the fumarase-catalyzed reaction.
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14
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A molecular model for the triplicated A domains of human factor VIII based on the crystal structure of human ceruloplasmin. Blood 1997; 89:2413-21. [PMID: 9116285] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
The hemophilia A mutation database lists more than 160 missense mutations: each represents a molecular defect in the FVIII molecule, resulting in the X-linked bleeding disorder hemophilia A with a clinical presentation varying from mild to severe. Without a three-dimensional FVIII structure it is in most cases impossible to explain biological dysfunction in terms of the underlying molecular pathology. However, recently the crystal structure of the homologous human plasma copper-binding protein ceruloplasmin (hCp) has been solved, and the A domains of FVIII share approximately 34% sequence identity with hCp. This advance has enabled the building of a molecular model of the A domains of FVIII based on the sequence identity between the two proteins. The model allows exploration of predictions regarding the general features of the FVIII molecule, such as the binding-sites for factor IXa and activated protein C; it has also allowed the mapping of more than 30 selected mutations with known phenotype from the database, and the prediction of hypothetical links to dysfunction in all but a few cases. A computer-generated molecular model such as that reported here cannot substitute for a crystal structure. However, until such a structure for FVIII becomes available, the model represents a significant advance in modeling FVIII; it should prove a useful tool for exploiting the increasing amount of information in the hemophilia A mutation database, and for selecting appropriate targets for investigation of the structure-function relationships via mutagenesis and expression in vitro.
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Crystallization and preliminary X-ray studies of nitrogenase component 1 (the MoFe protein) from Klebsiella pneumoniae. ACTA CRYSTALLOGRAPHICA SECTION D: BIOLOGICAL CRYSTALLOGRAPHY 1997; 53:227-8. [PMID: 15299965 DOI: 10.1107/s0907444996012681] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Two crystal forms of component 1 (the MoFe protein) of nitrogenase from Klebsiella pneumoniae have been isolated and characterized. The triclinic form has cell dimensions a = 76.0, b = 109.6, c = 144.6 A, alpha = 80.3, beta = 74.9 and gamma = 69.6 degrees, diffracts to around 3.0 A and has two molecules in the asymmetric unit. The monoclinic form belongs to space group P2(1) with a = 76.6, b = 127.8, c = 109.1 A and beta = 104.6 degrees (frozen at 100 K), diffracts to 1.5 A and has one molecule in the asymmetric unit. At this resolution the outstanding questions concerning the structure and the operation of the enzyme, in particular the linkage between the Fe(4)S(4) units in the P clusters, the true geometry of the apparently trigonal Fe atoms in the FeMoco and the reduction site itself, should be answerable.
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Crystallization and preliminary X-ray crystallographic analysis of the putative [6Fe–6S] prismane protein from Desulfovibrio vulgaris (Hildenborough). ACTA CRYSTALLOGRAPHICA SECTION D: BIOLOGICAL CRYSTALLOGRAPHY 1996; 52:1211-3. [PMID: 15299589 DOI: 10.1107/s0907444996007767] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Crystals of the prismane protein from Desulfovibrio vulgaris (Hildenborough) containing a putative [6Fe-6S] cluster have been obtained and X-ray data collected to a resolution of 1.7 A using synchrotron radiation. The unit cell is orthorhombic with a = 64.1, b = 65.1 and c = 154.1 A, space group P2(1)2(1)2(1) (No. 19). The unit cell will readily accommodate four molecules of molecular weight 60 kDa with a corresponding solvent content of approximately 48%.
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The structure of human ceruloplasmin at 3.0 Å resolution: the beginning of the end of an enigma. Acta Crystallogr A 1996. [DOI: 10.1107/s0108767396096298] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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18
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The X-ray structure of human serum ceruloplasmin at 3.1 Å: nature of the copper centres. J Biol Inorg Chem 1996. [DOI: 10.1007/s007750050018] [Citation(s) in RCA: 187] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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The haemophilia A mutation search test and resource site, home page of the factor VIII mutation database: HAMSTeRS. Nucleic Acids Res 1996; 24:100-2. [PMID: 8594555 PMCID: PMC145612 DOI: 10.1093/nar/24.1.100] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
In order to facilitate easy access to and aid understanding of the causes of haemophilia A at the molecular level we have constructed HAMSTeRS, the third release of the factor VIII mutation database and the first release of this database that may be accessed and interrogated over the internet through a World Wide Web browser. The database also presents a review of the structure and function of factor VIII and the molecular genetics of haemophilia A, a real time update of the biostatistics of each parameter in the database, a molecular model of the A1, A2 and A3 domains of the factor VIII protein (based on the crystal structure of caeruloplasmin) and a bulletin board for discussion of issues in the molecular biology of factor VIII.
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The structure of avian eye lens delta-crystallin reveals a new fold for a superfamily of oligomeric enzymes. NATURE STRUCTURAL BIOLOGY 1994; 1:724-34. [PMID: 7634077 DOI: 10.1038/nsb1094-724] [Citation(s) in RCA: 55] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
The crystal structure of turkey delta-crystallin, a principal soluble components of the avian lens, has been determined to a resolution of 2.5 A. It is a tetramer, of 200,000 M(r), with 222 symmetry. The subunit has a new fold composed of three mainly alpha-helical domains. One domain is a bundle of five long helices which forms a 20-helix bundle at the core of the tetramer. delta-crystallin shares approximately 90% sequence identity with the enzyme argininosuccinate lyase (EC 4.3.2.1), indicating that it is an example of a 'hijacked' enzyme. It is also distantly related to the class II fumarases, aspartases, adenylosuccinases and 3-carboxy-cis,cis-muconate lactonising enzyme. The structure reveals a putative active-site cleft which is located on the boundary between three subunits of the tetramer. This is the first three-dimensional structure of a representative of this superfamily of enzymes.
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22
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The effect of polymer architecture on the SIMS spectra of glycolide/trimethylene carbonate copolymers. SURF INTERFACE ANAL 1993. [DOI: 10.1002/sia.740201305] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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23
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Theoretical and methodological differentiation of moderation and mediation. Nurs Res 1993; 42:276-9. [PMID: 8415040] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
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24
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25
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Structural studies on serum transferrin: the central protein of iron metabolism. Acta Crystallogr A 1987. [DOI: 10.1107/s0108767387084654] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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26
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Structural studies on the lens β, γ crystallins. Acta Crystallogr A 1987. [DOI: 10.1107/s0108767387084514] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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27
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Bifunctional variations of the antidepressant amitriptyline theme. Chem Pharm Bull (Tokyo) 1985; 33:4847-55. [PMID: 3830418 DOI: 10.1248/cpb.33.4847] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
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28
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Abstract
Knowledge of the three-dimensional structure of bovine gamma II-crystallin has provided the basis for building molecular models using computer graphics of two human gamma-crystallins, the sequences of which have recently been determined. The tertiary structures of these gamma-crystallins are predicted to be highly conserved. They have extensive networks of interacting charges on their surfaces, which may contribute to their thermodynamic stability and partially define the degree of water retention in the lens. The human crystallins appear to be more hydrophobic than the bovine molecule. All have arrangements of cysteine thiols which may be important as electron sinks and reserve redox potential in the normal lens but which may contribute to protein aggregation in cataract.
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Abstract
We report the X-ray structure analysis and refinement at 1.9 A resolution of calf gamma-II crystallin, a lens-specific protein. The sequence of Croft (1972) has been modified to give a polypeptide chain of 174 residues (cf. 165). The protein has a symmetrical, hierarchical structure of two globular domains each comprising two similar "Greek key" motifs, consecutive along the polypeptide chain, and related by a pseudo 2-fold axis. The two domains pack together with a single connection and are related by a further pseudo 2-fold axis which bisects the angle between the intra-domain dyads. Forty-two pairs of C alpha positions for the two most similar motifs have root-mean-square separation at best fit of 0.69 A. The N and C-terminal domains gave root-mean-square separation of 0.89 A for 82 pairs of C alpha atoms at best fit. In each domain the two Greek key motifs form a pair of four-stranded antiparallel beta-pleated sheets, each sheet composed of three stands from one motif and one from the other. The sheets pack together in a wedge shape, closed at the top by the loops connecting the third and fourth strands of each motif. The first two strands of each motif form an extended beta-hairpin which is folded on to the beta-sheet. The packing of each motif into the globular domains involves a staggered bilayer of side-chains between each pair of beta-sheets which does not preserve the pseudo 2-fold axes observed in the C alpha position topology. In the core of each domain there are interactions between polarizable aromatic groups and sulphur-containing residues which may contribute to stability and may also serve to protect aromatic side-chains from ultraviolet light damage in the lens. At the surface of the molecule over half the ionic side-chains are closely paired, which probably stabilizes the tertiary fold and may reduce the water bound. Crystal lattice interactions are described which may be similar to those occurring in vivo in the lens between crystallins. Seven cysteine residues have been identified in the structure and these may have a role in the thermodynamic stability of the molecule, its intermolecular interactions under the normal reducing conditions of the lens, and also in the aggregation and cross-linking which occur in some forms of cataract. Three of these residues, Cys18, Cys23 and Cys74, form a cluster in the N-terminal domain.(ABSTRACT TRUNCATED AT 400 WORDS)
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Identification and management of psychosocial problems by health visitors. HEALTH VISITOR 1982; 55:165-9. [PMID: 6926421] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
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31
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Abstract
The three-dimensional structure of the eye lens protein, bovine gamma-crystallin II, has been determined at 2.6 A resolution. The protein has a tow domain beta-structure, folded into four remarkably similar 'Greed key' motifs, and shows the highest internal symmetry of any protein studied by X-ray analysis. Although the symmetrical structure seems very stable, the arrangement of the sulphydryl groups would allow intramolecular cross-linking leading to possible destabilization, and intermolecular cross-linking leading to aggregation, both of which may be important to cataract formation.
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Behavioural approaches. Nursing 1980:808-9. [PMID: 6904892] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
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33
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Vitamin D -- too much of a good thing? HEALTH VISITOR 1980; 53:318-9. [PMID: 6901728] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
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34
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Abstract
This paper concerns a new clinical role for psychiatric nurses--as case managers for selected adult neurotics with behaviour problems. The role involves unusual autonomy. The selection and training procedures are unusually rigorous and focus on general case-management as much as behavioural skills. The number of service posts offered these therapists is rising. These developments have wide implications for other personnel, particularly in respect of authority and responsibility boundaries, selection and training procedures, and team structure.
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Abstract
Fifty-one out-patients with social skills deficits (two-thirds men) completed ten weekly sessions of 75-minute group treatment; 44 were followed up for a mean of 16 months. Random assignment was to one of three conditions: (I) Cohesive group discussion; (2) Modelling and role-rehearsal; or (3) Modelling and role-rehearsal + daily social homework. All three treatment conditions produced significant but incomplete improvement at the end of treatment and follow-up. The two role-rehearsal conditions were significantly superior to group discussion on several measures. Patients who completed daily social homework assignments did significantly better than patients who completed control homework. Alcohol and drug abuse patients usually dropped out. Schizophrenic patients in remission had lost their improvement at follow-up. Patients with other diagnoses retained their gains to 16-month follow-up.
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Abstract
A young man was followed-up over three years who had severe obsessive-compulsive rituals and ruminations, interpersonal deficits, complicating depression and a history of childhood autism. Intensive behavioural treatment was given in an operant framework, with exposure in vivo, modelling, response prevention and social skills training. Compulsive rituals improved markedly and lastingly, but ruminations and social defects persisted. When intercurrent depression occurred dothiepin facilitated behavioural treatment. Adjustment remained fragile. Minimum maintenance treatment in the community could not be adequately arranged, so that gains made in hospital were partly lost at follow-up, despite continuing improvement in rituals.
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37
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Suicide. NURSING MIRROR AND MIDWIVES JOURNAL 1976; 143:suppl 9:i-iv. [PMID: 1047412] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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Nurse-therapists at work: six case studies. 6. Sexual deviation in a young man. NURSING MIRROR AND MIDWIVES JOURNAL 1975; 140:63-4. [PMID: 1039699] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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Nurse-therapists at work: six case studies. 1. Pigeon phobia. NURSING MIRROR AND MIDWIVES JOURNAL 1975; 140:58. [PMID: 1039694] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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