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Dohn AO, Markmann V, Nimmrich A, Haldrup K, Møller KB, Nielsen MM. Eliminating finite-size effects on the calculation of x-ray scattering from molecular dynamics simulations. J Chem Phys 2023; 159:124115. [PMID: 38127395 DOI: 10.1063/5.0164365] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2023] [Accepted: 09/01/2023] [Indexed: 12/23/2023] Open
Abstract
Structural studies using x-ray scattering methods for investigating molecules in solution are shifting focus toward describing the role and effects of the surrounding solvent. However, forward models based on molecular dynamics (MD) simulations to simulate structure factors and x-ray scattering from interatomic distributions such as radial distribution functions (RDFs) face limitations imposed by simulations, particularly at low values of the scattering vector q. In this work, we show how the value of the structure factor at q = 0 calculated from RDFs sampled from finite MD simulations is effectively dependent on the size of the simulation cell. To eliminate this error, we derive a new scheme to renormalize the sampled RDFs based on a model of the excluded volume of the particle-pairs they were sampled from, to emulate sampling from an infinite system. We compare this new correction method to two previous RDF-correction methods, developed for Kirkwood-Buff theory applications. We present a quantitative test to assess the reliability of the simulated low-q scattering signal and show that our RDF-correction successfully recovers the correct q = 0 limit for neat water. We investigate the effect of MD-sampling time on the RDF-corrections, before advancing to a molecular example system, comprised of a transition metal complex solvated in a series of water cells with varying densities. We show that our correction recovers the correct q = 0 behavior for all densities. Furthermore, we employ a simple continuum scattering model to dissect the total scattering signal from the solvent-solvent structural correlations in a solute-solvent model system to find two distinct contributions: a non-local density-contribution from the finite, fixed cell size in NVT simulations, and a local contribution from the solvent shell. We show how the second contribution can be approximated without also including the finite-size contribution. Finally, we provide a "best-practices"-checklist for experimentalists planning to incorporate explicit solvation MD simulations in future work, offering guidance for improving the accuracy and reliability of structural studies using x-ray scattering methods in solution.
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Affiliation(s)
- A O Dohn
- Department of Physics, Technical University of Denmark, 2800 Lyngby, Denmark
- Science Institute and Faculty of Physical Sciences, VR-III, University of Iceland, Reykjavík 107, Iceland
| | - V Markmann
- Department of Physics, Technical University of Denmark, 2800 Lyngby, Denmark
| | - A Nimmrich
- Department of Physics, Technical University of Denmark, 2800 Lyngby, Denmark
| | - K Haldrup
- Department of Physics, Technical University of Denmark, 2800 Lyngby, Denmark
| | - K B Møller
- Department of Chemistry, Technical University of Denmark, 2800 Lyngby, Denmark
| | - M M Nielsen
- Department of Physics, Technical University of Denmark, 2800 Lyngby, Denmark
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Klem L, Nielsen MM, Gestsdóttir SB, Frandsen SL, Prichardt S, Andreasen JT. Assessing attention and impulsivity in the variable stimulus duration and variable intertrial interval rodent continuous performance test schedules using dopamine receptor antagonists in female C57BL/6JRj mice. Psychopharmacology (Berl) 2023; 240:1651-1666. [PMID: 37378887 PMCID: PMC10349733 DOI: 10.1007/s00213-023-06387-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/27/2023] [Accepted: 05/10/2023] [Indexed: 06/29/2023]
Abstract
RATIONALE Dopaminergic dysfunction is implicated in disorders of impulsivity and inattention. The rodent continuous performance test (rCPT) has been used to quantify changes in attention and impulsivity. OBJECTIVE To examine the roles of dopamine receptors in attention and impulsivity behaviours measured in the rCPT variable stimulus duration (vSD) and the variable intertrial interval schedules (vITI) using DA receptor antagonists. METHODS Two cohorts of 35 and 36 female C57BL/6JRj mice were examined separately in the rCPT, vSD, and vITI schedules, respectively. Both cohorts received antagonists of the following receptors: D1/5 (SCH23390, SCH: 0.01, 0.02, 0.04 mg/kg) and D2/3 (raclopride, RAC 0.03, 0.10, 0.30 mg/kg) in consecutive balanced Latin square designs with flanking reference measurements. The antagonists were subsequently examined for effects on locomotor activity. RESULTS SCH showed similar effects in both schedules, and the effects were reference-dependent in the vITI schedule. SCH reduced responding, but improved response accuracy, impulsivity, discriminability, and locomotor activity. RAC showed mixed effects on responsivity, but improved accuracy and discriminability. The discriminability improvement was driven by an increase in hit rate in the vITI schedule and a reduction in false alarm rate in the vSD schedule. RAC also decreased locomotor activity. CONCLUSION Both D1/5 and D2/3 receptor antagonism reduced responding, but the outcome on discriminability differed, stemming from individual effects on hit and false alarm rate, and the weight of omissions within the calculation. The effects of SCH and RAC suggest that endogenous DA increases responding and impulsivity, but reduces accuracy and shows mixed effects on discriminability.
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Affiliation(s)
- L Klem
- Department of Drug Design and Pharmacology, University of Copenhagen, Universitetsparken 2, 2100, Copenhagen, Denmark
| | - M M Nielsen
- Department of Drug Design and Pharmacology, University of Copenhagen, Universitetsparken 2, 2100, Copenhagen, Denmark
| | - S B Gestsdóttir
- Department of Drug Design and Pharmacology, University of Copenhagen, Universitetsparken 2, 2100, Copenhagen, Denmark
| | - S L Frandsen
- Department of Drug Design and Pharmacology, University of Copenhagen, Universitetsparken 2, 2100, Copenhagen, Denmark
| | - S Prichardt
- Department of Drug Design and Pharmacology, University of Copenhagen, Universitetsparken 2, 2100, Copenhagen, Denmark
| | - J T Andreasen
- Department of Drug Design and Pharmacology, University of Copenhagen, Universitetsparken 2, 2100, Copenhagen, Denmark.
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Klem L, Nielsen MM, Gestsdóttir SB, Frandsen SL, Prichardt S, Andreasen JT. Assessing attention and impulsivity in the variable stimulus duration and variable intertrial interval rodent continuous performance test schedules using noradrenaline receptor antagonists in female C57BL/6JRj mice. Psychopharmacology (Berl) 2023; 240:1629-1650. [PMID: 37329343 PMCID: PMC10349758 DOI: 10.1007/s00213-023-06385-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/01/2022] [Accepted: 05/10/2023] [Indexed: 06/19/2023]
Abstract
RATIONALE Noradrenergic dysfunction is associated with disorders of impulsivity and inattention. The rodent continuous performance test (rCPT) quantifies changes in attention and impulsivity. OBJECTIVE To use NA receptor antagonists to examine the roles of NA on attention and impulsivity behaviours measured in the rCPT variable stimulus duration (vSD) and the variable intertrial interval (vITI) schedules. METHODS Two cohorts of 36 female C57BL/6JRj mice were examined separately in the rCPT vSD and vITI schedules. Both cohorts received antagonists of the following adrenoceptors: α1 (doxazosin, DOX: 1.0, 3.0, 10.0 mg/kg), α2 (yohimbine, YOH: 0.1, 0.3, 1.0 mg/kg), and β1/2 (propranolol, PRO: 1.0, 3.0, 10.0 mg/kg) in consecutive balanced Latin square designs with flanking reference measurements. The antagonists were subsequently examined for effects on locomotor activity. RESULTS DOX showed similar effects in both schedules, improving discriminability and accuracy, and reducing responding and impulsivity, and DOX also reduced locomotor activity. YOH showed prominent effects in the vSD schedule to increase responding and impulsivity, while impairing discriminability and accuracy. YOH did not affect locomotor activity. PRO increased responding and impulsivity, decreased accuracy, but did not affect discriminability or locomotor activity. CONCLUSION Antagonism of α2 or β1/2 adrenoceptors caused similar increases in responding and impulsivity and worsened attentional performance, while α1 adrenoceptor antagonism showed the opposite effects. Our results suggest that endogenous NA exerts bidirectional control of most behaviours in the rCPT. The parallel vSD and vITI studies showed a substantial overlap in effects, but also some differences that indicate differing sensitivity towards noradrenergic manipulations.
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Affiliation(s)
- L Klem
- Dept. of Drug Design and Pharmacology, University of Copenhagen, Universitetsparken 2, 2100, Copenhagen, Denmark
| | - M M Nielsen
- Dept. of Drug Design and Pharmacology, University of Copenhagen, Universitetsparken 2, 2100, Copenhagen, Denmark
| | - S B Gestsdóttir
- Dept. of Drug Design and Pharmacology, University of Copenhagen, Universitetsparken 2, 2100, Copenhagen, Denmark
| | - S L Frandsen
- Dept. of Drug Design and Pharmacology, University of Copenhagen, Universitetsparken 2, 2100, Copenhagen, Denmark
| | - S Prichardt
- Dept. of Drug Design and Pharmacology, University of Copenhagen, Universitetsparken 2, 2100, Copenhagen, Denmark
| | - J T Andreasen
- Dept. of Drug Design and Pharmacology, University of Copenhagen, Universitetsparken 2, 2100, Copenhagen, Denmark.
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Kong QY, Laursen MG, Haldrup K, Kjær KS, Khakhulin D, Biasin E, van Driel TB, Wulff M, Kabanova V, Vuilleumier R, Bratos S, Nielsen MM, Gaffney KJ, Weng TC, Koch MHJ. Initial metal-metal bond breakage detected by fs X-ray scattering in the photolysis of Ru 3(CO) 12 in cyclohexane at 400 nm. Photochem Photobiol Sci 2019; 18:319-327. [PMID: 30628601 DOI: 10.1039/c8pp00420j] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
Abstract
Using femtosecond resolution X-ray solution scattering at a free electron laser we were able to directly observe metal-metal bond cleavage upon photolysis at 400 nm of Ru3(CO)12, a prototype for the photochemistry of transition metal carbonyls. This leads to the known single intermediate Ru3(CO)11(μ-CO)*, with a bridging ligand (μCO) and where the asterisk indicates an open Ru3-ring. This loses a CO ligand on a picosecond time scale yielding a newly observed triple bridge intermediate, Ru3(CO)8(μ-CO)3*. This loses another CO ligand to form the previously observed Ru3(CO)10, which returns to Ru3(CO)12via the known single-bridge Ru3(CO)10(μ-CO). These results indicate that contrary to long standing hypotheses, metal-metal bond breakage is the only chemical reaction immediately following the photolysis of Ru3(CO)12 at 400 nm. Combined with previous picosecond resolution X-ray scattering data and time resolved infrared spectroscopy these results yield a new mechanism for the photolysis of Ru3(CO)12.
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Affiliation(s)
- Q Y Kong
- Synchrotron Soleil, L'Orme des Merisiers St Aubin, Gif-sur-Yvette, F-91192, France
| | - M G Laursen
- Department of Physics, Technical University of Denmark, Fysikvej 307, Kongens Lyngby, DK-2800, Denmark
| | - K Haldrup
- Department of Physics, Technical University of Denmark, Fysikvej 307, Kongens Lyngby, DK-2800, Denmark
| | - K S Kjær
- Department of Physics, Technical University of Denmark, Fysikvej 307, Kongens Lyngby, DK-2800, Denmark
| | - D Khakhulin
- European XFEL GmbH, Holzkoppel 4, Schenefeld, D-22869, Germany
| | - E Biasin
- Department of Physics, Technical University of Denmark, Fysikvej 307, Kongens Lyngby, DK-2800, Denmark.,PULSE Institute, SLAC National Accelerator Laboratory, Menlo Park, California, 94025, USA
| | - T B van Driel
- LCLS, SLAC National Accelerator Laboratory, Menlo Park, California, 94025, USA
| | - M Wulff
- European Synchrotron Radiation Facility, Grenoble Cedex, BP 220 F-38043, France
| | - V Kabanova
- European Synchrotron Radiation Facility, Grenoble Cedex, BP 220 F-38043, France
| | - R Vuilleumier
- Ecole Normale Supérieure, PSL Research University, UPMC Univ Paris 06, CNRS, Département de Chimie, PASTEUR, 24 rue Lhomond, Paris, F-75005, France.,Sorbonne Universités, UPMC Univ Paris 06, ENS, CNRS, PASTEUR, Paris, F-75005, France
| | - S Bratos
- Sorbonne Universités, UPMC Univ Paris 06, UMR 7600, LPTMC, Paris, F-75005, France
| | - M M Nielsen
- Department of Physics, Technical University of Denmark, Fysikvej 307, Kongens Lyngby, DK-2800, Denmark
| | - K J Gaffney
- PULSE Institute, SLAC National Accelerator Laboratory, Menlo Park, California, 94025, USA
| | - T C Weng
- Center for High Pressure Science & Technology Advanced Research, 1690 Cailun Rd, Bldg. 6-408, Pudong, Shanghai, 201203, China.
| | - M H J Koch
- European Molecular Biology Laboratory, Hamburg Outstation, EMBL c/o DESY, Notkestrasse 85, Hamburg, D-22603, Germany
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Affiliation(s)
- B Dyring-Andersen
- Department of Dermato-Allergology, Gentofte Hospital, University of Copenhagen, Hellerup, Denmark
| | - M M Nielsen
- Department of Immunology and Microbiology, University of Copenhagen, Copenhagen, Denmark
| | - C Geisler
- Department of Immunology and Microbiology, University of Copenhagen, Copenhagen, Denmark
| | - C M Bonefeld
- Department of International Health, Immunology and Microbiology, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark
| | - L Skov
- Department of Dermato-Allergology, Gentofte Hospital, University of Copenhagen, Hellerup, Denmark
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6
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Bressler C, Gawelda W, Galler A, Nielsen MM, Sundström V, Doumy G, March AM, Southworth SH, Young L, Vankó G. Solvation dynamics monitored by combined X-ray spectroscopies and scattering: photoinduced spin transition in aqueous [Fe(bpy)3]2+. Faraday Discuss 2014; 171:169-78. [DOI: 10.1039/c4fd00097h] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We have studied the photoinduced low spin (LS) to high spin (HS) conversion of aqueous Fe(bpy)3 with pulse-limited time resolution. In a combined setup permitting simultaneous X-ray diffuse scattering (XDS) and spectroscopic measurements at a MHz repetition rate we have unraveled the interplay between intramolecular dynamics and the intermolecular caging solvent response with 100 ps time resolution. On this time scale the ultrafast spin transition including intramolecular geometric structure changes as well as the concomitant bulk solvent heating process due to energy dissipation from the excited HS molecule are long completed. The heating is nevertheless observed to further increase due to the excess energy between HS and LS states released on a subnanosecond time scale. The analysis of the spectroscopic data allows precise determination of the excited population which efficiently reduces the number of free parameters in the XDS analysis, and both combined permit extraction of information about the structural dynamics of the first solvation shell.
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Affiliation(s)
- C. Bressler
- European XFEL
- 22761 Hamburg, Germany
- The Hamburg Centre for Ultrafast Imaging
- 22761 Hamburg, Germany
| | | | | | - M. M. Nielsen
- Centre for Molecular Movies
- Dept. of Physics
- Technical University of Denmark
- DK-2800 Kongens Lyngby, Denmark
| | - V. Sundström
- Dept. of Chemical Physics
- Lund University
- 22100 Lund, Sweden
| | - G. Doumy
- Argonne National Laboratory
- , USA
| | | | | | - L. Young
- Wigner Research Centre for Physics
- Hungarian Academy Sciences
- H-1525 Budapest, Hungary
| | - G. Vankó
- Wigner Research Centre for Physics
- Hungarian Academy Sciences
- H-1525 Budapest, Hungary
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Haldrup K, Vankó G, Gawelda W, Galler A, Doumy G, March AM, Kanter EP, Bordage A, Dohn A, van Driel TB, Kjær KS, Lemke HT, Canton SE, Uhlig J, Sundström V, Young L, Southworth SH, Nielsen MM, Bressler C. Guest–Host Interactions Investigated by Time-Resolved X-ray Spectroscopies and Scattering at MHz Rates: Solvation Dynamics and Photoinduced Spin Transition in Aqueous Fe(bipy)32+. J Phys Chem A 2012; 116:9878-87. [DOI: 10.1021/jp306917x] [Citation(s) in RCA: 100] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- K. Haldrup
- Centre for Molecular Movies,
Department of Physics, Technical University of Denmark, DK-2800 Lyngby, Denmark
| | - G. Vankó
- Wigner Research Centre for Physics, Hungarian Academy Sciences, H-1525 Budapest, POB 49,
Hungary
| | - W. Gawelda
- European XFEL, Albert-Einstein Ring 19, D-22 761 Hamburg, Germany
| | - A. Galler
- European XFEL, Albert-Einstein Ring 19, D-22 761 Hamburg, Germany
| | - G. Doumy
- Argonne National Laboratory, 9700 South Cass Avenue, Argonne, Illinois
60439, United States
| | - A. M. March
- Argonne National Laboratory, 9700 South Cass Avenue, Argonne, Illinois
60439, United States
| | - E. P. Kanter
- Argonne National Laboratory, 9700 South Cass Avenue, Argonne, Illinois
60439, United States
| | - A. Bordage
- Wigner Research Centre for Physics, Hungarian Academy Sciences, H-1525 Budapest, POB 49,
Hungary
| | - A. Dohn
- Chemistry
Department, Danish Technical University, DK-2800 Lyngby, Denmark
| | - T. B. van Driel
- Centre for Molecular Movies,
Department of Physics, Technical University of Denmark, DK-2800 Lyngby, Denmark
| | - K. S. Kjær
- Centre for Molecular Movies,
Niels Bohr Institute, University of Copenhagen, DK-2100 Copenhagen, Denmark
| | - H. T. Lemke
- Linac Coherent Light Source, SLAC National Accelerator Laboratory, Menlo Park, California
94025, United States
| | | | | | | | - L. Young
- Argonne National Laboratory, 9700 South Cass Avenue, Argonne, Illinois
60439, United States
| | - S. H. Southworth
- Argonne National Laboratory, 9700 South Cass Avenue, Argonne, Illinois
60439, United States
| | - M. M. Nielsen
- Centre for Molecular Movies,
Department of Physics, Technical University of Denmark, DK-2800 Lyngby, Denmark
| | - C. Bressler
- European XFEL, Albert-Einstein Ring 19, D-22 761 Hamburg, Germany
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Pasarín IS, Bovet N, Glyvradal M, Nielsen MM, Bohr J, Feidenhans'l R, Stipp SLS. Atomic modifications by synchrotron radiation at the calcite-ethanol interface. J Synchrotron Radiat 2012; 19:530-535. [PMID: 22713885 DOI: 10.1107/s0909049512021504] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/13/2011] [Accepted: 05/11/2012] [Indexed: 06/01/2023]
Abstract
This article reports on studies of the chemical alterations induced by synchrotron radiation at the calcite-ethanol interface, a simple model system for interfaces between minerals and more complex organic molecules containing OH groups. A combination of X-ray reflectivity and X-ray photoelectron spectroscopy of natural calcite, cleaved in distilled ethanol to obtain new clean interfaces, indicated that, during a 5 h period, the two top atomic layers of calcite, CaCO(3), transform into calcium oxide, CaO, by releasing CO(2). Also, the occupation of the first ordered layer of ethanol attached to calcite by hydrogen bonds almost doubles. Comparison between radiated and non-radiated areas of the same samples demonstrate that these effects are induced only by radiation and not caused by aging. These observations contribute to establishing a time limit for synchrotron experiments involving fluid-mineral interfaces where the polar OH group, as present in ethanol, plays a key role in their molecular structure and bonding. Also, the chemical evolution observed in the interface provides new insight into the behavior of some complex organic molecules involved in biomineralization processes.
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Affiliation(s)
- I S Pasarín
- Nano-Science Center, Department of Chemistry, University of Copenhagen, Denmark.
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Pasarín IS, Yang M, Bovet N, Glyvradal M, Nielsen MM, Bohr J, Feidenhans'l R, Stipp SLS. Molecular ordering of ethanol at the calcite surface. Langmuir 2012; 28:2545-50. [PMID: 22060260 DOI: 10.1021/la2021758] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
To produce biominerals, such as shells, bones, and teeth, living beings create organic compounds that control the growth of the solid phase. Investigating the atomic scale behavior of individual functional groups at the mineral-fluid interface provides fundamental information that is useful for constructing accurate predictive models for natural systems. Previous investigations of the activity of coccolith-associated polysaccharides (CAP) on calcite, using atomic force microscopy (AFM) [Henriksen, K., Young, J. R., Bown, P. R., and Stipp, S. L. S. Palentology 2004, 43 (Part 3), 725-743] and molecular dynamics (MD) modeling [Yang, M., Stipp, S. L. S., and Harding, J. H. Cryst. Growth Des. 2008, 8 (11), 4066-4074], have suggested that OH functional groups control polysaccharide attachment. The purpose of this work was to characterize, using X-ray reflectivity (XR) combined with molecular dynamics (MD) simulations, the structuring on calcite of a layer of the simplest carbon chain molecule that contains an OH group, ethanol (CH(3)-CH(2)-OH). We found evidence that EtOH forms a highly ordered structure at the calcite surface, where the first layer molecules bond with calcite. The ethanol molecules stand up perpendicularly at the interface or nearly so. As a consequence, the fatty, CH(3) ends form a new surface, about 6 Å from the termination of the bulk calcite, and beyond that, there is a thin gap where ethanol density is low. Following is a more disordered layer that is two to three ethanol molecules thick, about 14 Å, where density more resembles that of bulk liquid ethanol. The good agreement between theory and experiment gives confidence that a theoretical approach can offer information about behavior in more complex systems.
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Affiliation(s)
- I S Pasarín
- Nano-Science Center, Department of Chemistry, University of Copenhagen, Universitetsparken 5, 2100 Copenhagen, Denmark.
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Rubin IMC, Dabelsteen S, Nielsen MM, White IR, Johansen JD, Geisler C, Bonefeld CM. Repeated exposure to hair dye induces regulatory T cells in mice. Br J Dermatol 2010; 163:992-8. [PMID: 20716223 DOI: 10.1111/j.1365-2133.2010.09988.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
BACKGROUND We have recently shown that commercial p-phenylenediamine (PPD)-containing hair dyes are potent immune activators that lead to severe contact hypersensitivity in an animal model. However, only a minority of people exposed to permanent hair dyes develops symptomatic contact hypersensitivity. This suggests that the majority of people exposed to hair dyes does not become sensitized or develop immunological tolerance. OBJECTIVES To study the immune response in mice repeatedly exposed to PPD-containing hair dye in a consumer-like manner. METHODS A commercial hair dye containing PPD was tested in C57BL/6 mice. The local immune response was measured by ear swelling and by histological examinations. The immune response in the draining lymph nodes was analysed by flow cytometry. RESULTS The hair dye induced local inflammation as seen by swelling and cell infiltration of the treated ears. In addition, exposure to hair dye caused T-cell activation as seen by T-cell proliferation and production of interferon-γ and interleukin (IL)-17 within the draining lymph nodes. The inflammatory response peaked at the fourth exposure to hair dye. From this point on, an upregulation of regulatory T cells and IL-10-producing cells was seen. CONCLUSIONS This study shows that PPD-containing hair dyes strongly affect the immune system. In addition to being potent skin sensitizers that activate inflammatory T cells, hair dyes also induce anti-inflammatory mechanisms. This might explain why many consumers can use hair dyes repeatedly without developing noticeable allergies, but it also raises the question whether the immune modulatory effects of hair dyes might influence the development of autoimmune diseases and cancers.
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Affiliation(s)
- I M C Rubin
- Department of International Health, Immunology and Microbiology, Faculty of Health Sciences, University of Copenhagen, Blegdamsvej 3, DK-2200 Copenhagen, Denmark
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Krüger AC, Raarup MK, Nielsen MM, Kristensen M, Besenbacher F, Kjems J, Birkedal V. Interaction of hnRNP A1 with telomere DNA G-quadruplex structures studied at the single molecule level. Eur Biophys J 2010; 39:1343-50. [DOI: 10.1007/s00249-010-0587-x] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/27/2009] [Revised: 12/07/2009] [Accepted: 02/12/2010] [Indexed: 10/19/2022]
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Nielsen MM, Seo ES, Dilokpimol A, Andersen J, Abou Hachem M, Naested H, Willemoës M, Bozonnet S, Kandra L, Gyémánt G, Haser R, Aghajari N, Svensson B. Roles of multiple surface sites, long substrate binding clefts, and carbohydrate binding modules in the action of amylolytic enzymes on polysaccharide substrates. BIOCATAL BIOTRANSFOR 2009. [DOI: 10.1080/10242420701789528] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Ejdrup T, Lemke HT, Haldrup K, Nielsen TN, Arms DA, Walko DA, Miceli A, Landahl EC, Dufresne EM, Nielsen MM. Picosecond time-resolved laser pump/X-ray probe experiments using a gated single-photon-counting area detector. J Synchrotron Radiat 2009; 16:387-390. [PMID: 19395803 DOI: 10.1107/s0909049509004658] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/09/2008] [Accepted: 02/09/2009] [Indexed: 05/25/2023]
Abstract
The recent developments in X-ray detectors have opened new possibilities in the area of time-resolved pump/probe X-ray experiments; this article presents the novel use of a PILATUS detector to achieve X-ray pulse duration limited time-resolution at the Advanced Photon Source (APS), USA. The capability of the gated PILATUS detector to selectively detect the signal from a given X-ray pulse in 24 bunch mode at the APS storage ring is demonstrated. A test experiment performed on polycrystalline organic thin films of alpha-perylene illustrates the possibility of reaching an X-ray pulse duration limited time-resolution of 60 ps using the gated PILATUS detector. This is the first demonstration of X-ray pulse duration limited data recorded using an area detector without the use of a mechanical chopper array at the beamline.
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Affiliation(s)
- T Ejdrup
- Danish National Research Foundation Centre for Molecular Movies, Niels Bohr Institute, University of Copenhagen, Universitetsparken 5, 2100 Copenhagen Ø, Denmark.
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Abstract
Here, we report a detailed analysis of changes in gene expression in Drosophila melanogaster selected for ecologically relevant environmental stress resistance traits. We analysed females from seven replicated selection regimes and one control regime using whole genome gene expression arrays. When compared with gene expression profiles of control lines, we were able to detect consistent selection responses at the transcript level in each specific selection regime and also found a group of differentially expressed genes that were changed among all selected lines. Replicated selection lines showed similar changes in gene expression (compared with controls) and thus showed that 10 generations of artificial selection give a clear signal with respect to the resulting gene expression profile. The changes in gene expression in lines selected for increased longevity, desiccation and starvation resistance, respectively, showed high similarities. Cold resistance-selected lines showed little differentiation from controls. Different methods of heat selection (heat survival, heat knock down and constant 30 degrees C) showed little similarity verifying that different mechanisms are involved in high temperature adaptation. For most individual selection regimes, and in the comparison of all selected lines and controls, the gene expression changes were exclusively in one direction, although the different selection regimes varied in the direction of response. The responses to selection restricted to individual selection regimes can be interpreted as stress specific, whereas the response shared among all selected lines can be considered as a general stress response. Here, we identified genes belonging to both types of responses to selection for stress resistance.
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Affiliation(s)
- J G Sørensen
- Department of Ecology and Genetics, University of Aarhus, Aarhus C, Denmark.
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15
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Severinsen JE, Bjarkam CR, Kiaer-Larsen S, Olsen IM, Nielsen MM, Blechingberg J, Nielsen AL, Holm IE, Foldager L, Young BD, Muir WJ, Blackwood DHR, Corydon TJ, Mors O, Børglum AD. Evidence implicating BRD1 with brain development and susceptibility to both schizophrenia and bipolar affective disorder. Mol Psychiatry 2006; 11:1126-38. [PMID: 16924267 DOI: 10.1038/sj.mp.4001885] [Citation(s) in RCA: 68] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Linkage studies suggest that chromosome 22q12-13 may contain one or more shared susceptibility genes for schizophrenia (SZ) and bipolar affective disorder (BPD). In a Faeroese sample, we previously reported association between microsatellite markers located at 22q13.31-qtel and both disorders. The present study reports an association analysis across five genes (including 14 single nucleotide and two microsatellite polymorphisms) in this interval using a case-control sample of 162 BPD, 103 SZ patients and 200 controls. The bromodomain-containing 1 gene (BRD1), which encodes a putative regulator of transcription showed association with both disorders with minimal P-values of 0.0046 and 0.00001 for single marker and overall haplotype analysis, respectively. A specific BRD1 2-marker 'risk' haplotype showed a frequency of approximately 10% in the combined case group versus approximately 1% in controls (P-value 2.8 x 10(-7)). Expression analysis of BRD1 mRNA revealed widespread expression in mammalian brain tissue, which was substantiated by immunohistochemical detection of BRD1 protein in the nucleus, perikaryal cytosol and proximal dendrites of the neurons in the adult rat, rabbit and human CNS. Quantitative mRNA analysis in developing fetal pig brain revealed spatiotemporal differences with high expression at early embryonic stages, with intense nuclear and cytosolar immunohistochemical staining of the neuroepithelial layer and early neuroblasts, whilst more mature neurons at later embryonic stages had less nuclear staining. The results implicate BRD1 with SZ and BPD susceptibility and provide evidence that suggests a role for BRD1 in neurodevelopment.
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Affiliation(s)
- J E Severinsen
- Institute of Human Genetics, University of Aarhus, Aarhus, Denmark
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Abstract
Underlying the nuclear envelope (NE) of most eukaryotic cells is the nuclear lamina, a meshwork consisting largely of coiled-coil nuclear intermediate filament proteins that play a critical role in nuclear organization and gene expression, and are vital for the structural stability of the NE/nucleus. By confocal microscopy and micromanipulation of the NE in living cells and isolated nuclei, we show that the NE undergoes deformations without large-scale rupture and maintains structural stability when exposed to mechanical stress. In conjunction with image analysis, we have developed theory for a two-dimensional elastic material to quantify NE elastic behaviour. We show that the NE is elastic and exhibits characteristics of a continuous two-dimensional solid, including connections between lamins and the embedded nuclear pore complexes. Correlating models of NE lateral organization to the experimental findings indicates a heterogeneous lateral distribution of NE components on a mesoscopic scale.
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Affiliation(s)
- A C Rowat
- MEMPHYS-Center for Biomembrane Physics, Department of Physics, Campusvej 55, University of Southern Denmark, 5230 Odense M, Denmark
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Apitz D, Bertram RP, Benter N, Hieringer W, Andreasen JW, Nielsen MM, Johansen PM, Buse K. Investigation of chromophore-chromophore interaction by electro-optic measurements, linear dichroism, x-ray scattering, and density-functional calculations. Phys Rev E Stat Nonlin Soft Matter Phys 2005; 72:036610. [PMID: 16241595 DOI: 10.1103/physreve.72.036610] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/09/2005] [Indexed: 05/05/2023]
Abstract
Free-beam interferometry and angle-resolved absorption spectra are used to investigate the linear electro-optic coefficients and the linear dichroism in photoaddressable bis-azo copolymer thin films. From the first- and second order parameters deduced, the chromophore orientation distribution is calculated and displayed for several poling temperatures and chromophore concentrations. The influence of dipole-dipole interaction on the overall polymer dynamics is discussed. The first order parameter, and therefore the Pockels effect, peaks for a poling temperature of around 10 degrees C above the glass transition. The decrease of the Pockels effect above this temperature region is triggered by a head-to-tail chromophore orientation, i.e., a transition to a microcrystalline phase, increasing the second order parameter. Comparison of the experimentally observed absorption spectra and those obtained by density-functional calculations support the picture of differently aligned bis-azo dye molecules in a trans,trans configuration. Complementary wide-angle x-ray scattering is recorded to confirm the various kinds of ordering in samples poled at different temperatures.
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Affiliation(s)
- D Apitz
- Optics and Plasma Research Department, Risø National Laboratory, 4000 Roskilde, Denmark.
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Andreasen JW, Breiby DW, Hansen SR, Ramanujam PS, Drews M, Nielsen MM. Structural dynamics of the competing forces of light and matter. Acta Crystallogr A 2005. [DOI: 10.1107/s0108767305095218] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022] Open
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West K, Bay L, Nielsen MM, Velmurugu Y, Skaarup S. Electronic Conductivity of Polypyrrole−Dodecyl Benzene Sulfonate Complexes. J Phys Chem B 2004. [DOI: 10.1021/jp048153m] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Jensen LL, Nielsen MM, Justesen J, Hansen LL. Assignment of human NADH dehydrogenase (ubiquinone) 1 beta subcomplex 3 (NDUFB3) and of its four pseudogenes to human chromosomes 2q31.3, 1p13.3-->p13.1, 9q32-->q34.1, 14q22.3-->q23.1 and 14q32.2 by radiation hybrid mapping. Cytogenet Cell Genet 2001; 93:147-50. [PMID: 11474204 DOI: 10.1159/000056973] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Affiliation(s)
- L L Jensen
- Institute of Human Genetics, Bartholin Building, Aarhus University, DK-8000 Aarhus C, Denmark.
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21
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Knoop AS, Bentzen SM, Nielsen MM, Rasmussen BB, Rose C. Value of epidermal growth factor receptor, HER2, p53, and steroid receptors in predicting the efficacy of tamoxifen in high-risk postmenopausal breast cancer patients. J Clin Oncol 2001; 19:3376-84. [PMID: 11454885 DOI: 10.1200/jco.2001.19.14.3376] [Citation(s) in RCA: 87] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
PURPOSE Few studies have examined the possible importance of biologic prognostic factors in breast cancer connected with differentiation and growth in predicting response to a specific adjuvant treatment. HER2, epidermal growth factor receptor (EGFR), and p53 have all been suggested as possible markers of tamoxifen resistance. The aim of this study was to investigate interactions between adjuvant treatment with tamoxifen and the content of EGFR, HER2, and p53 in steroid receptor-positive patients. PATIENTS AND METHODS A total of 1,716 high-risk postmenopausal breast cancer patients were randomly assigned to treatment with tamoxifen (868 women) or to observation (848 women) in a prospective trial (Danish Breast Cancer Cooperative Group's 77c protocol). The content of the steroid receptors and expression of p53, EGFR, and HER2 were determined by immunohistochemical analysis of paraffin-embedded tissue. The length of follow-up was 10 years. The end point for this analysis was disease-free survival. RESULTS Multivariate analysis demonstrated no increased risk of recurrence after treatment with tamoxifen for HER2-, EGFR-, and p53-positive, high-risk, steroid receptor-positive patients. Patients with steroid receptor-positive tumors and positive immunohistochemical staining for HER2, EGFR or p53 benefited from treatment with tamoxifen for 1 year, although the latter variable contained independent prognostic information by itself. CONCLUSION With the statistical power of the present randomized study, we did not find support for the hypothesis that HER2/EGFR or p53 status predicts benefit from tamoxifen treatment in estrogen receptor-positive patients with early-stage breast cancer. Thus, neither HER2, EGFR, nor p53 overexpression/accumulation should be used as a contraindication for giving tamoxifen.
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Affiliation(s)
- A S Knoop
- Oncological Research Center, Odense University Hospital, Odense, Denmark.
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Pandey A, Fernandez MM, Steen H, Blagoev B, Nielsen MM, Roche S, Mann M, Lodish HF. Identification of a novel immunoreceptor tyrosine-based activation motif-containing molecule, STAM2, by mass spectrometry and its involvement in growth factor and cytokine receptor signaling pathways. J Biol Chem 2000; 275:38633-9. [PMID: 10993906 DOI: 10.1074/jbc.m007849200] [Citation(s) in RCA: 91] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
In an effort to clone novel tyrosine-phosphorylated substrates of the epidermal growth factor receptor, we have initiated an approach coupling affinity purification using anti-phosphotyrosine antibodies to mass spectrometry-based identification. Here, we report the identification of a signaling molecule containing a Src homology 3 domain as well as an immunoreceptor tyrosine-based activation motif (ITAM). This molecule is 55% identical to a previously isolated molecule designated signal transducing adaptor molecule (STAM) that was identified as an interleukin (IL)-2-induced phosphoprotein and is therefore designated STAM2. Tyrosine phosphorylation of STAM2 is induced by growth factors such as epidermal growth factor and platelet-derived growth factor as well as by cytokines like IL-3. Several of the deletion mutants tested except the one containing only the amino-terminal region underwent tyrosine phosphorylation upon growth factor stimulation, implying that STAM2 is phosphorylated on several tyrosine residues. STAM2 is downstream of the Jak family of kinases since coexpression of STAM2 with Jak1 or Jak2 but not an unrelated Tec family kinase, Etk, resulted in its tyrosine phosphorylation. In contrast to epidermal growth factor receptor-induced phosphorylation, this required the ITAM domain since mutants lacking this region did not undergo tyrosine phosphorylation. Finally, overexpression of wild type STAM2 led to an increase in IL-2-mediated induction of c-Myc promoter activation indicating that it potentiates cytokine receptor signaling.
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Affiliation(s)
- A Pandey
- Whitehead Institute for Biomedical Research, Cambridge, Massachusetts 02142, USA
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Nielsen MM, Christensen SV, Adams DL. Substitutional adsorption of Li on Al: The structure of the Al(111)-( sqrt 3 x sqrt 3)R30 degrees-Li phase. Phys Rev B Condens Matter 1996; 54:17902-17909. [PMID: 9985924 DOI: 10.1103/physrevb.54.17902] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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Christensen SV, Nerlov J, Nielsen K, Burchhardt J, Nielsen MM, Adams DL. Formation of surface ternary alloys by coadsorption of alkali metals on Al(111). Phys Rev Lett 1996; 76:1892-1895. [PMID: 10060547 DOI: 10.1103/physrevlett.76.1892] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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Burchhardt J, Nielsen MM, Adams DL, Lundgren E, Andersen JN, Stampfl C, Scheffler M, Schmalz A, Aminpirooz S, Haase J. Formation and structural analysis of a surface alloy: Al(111)-(2 x 2)-Na. Phys Rev Lett 1995; 74:1617-1620. [PMID: 10059074 DOI: 10.1103/physrevlett.74.1617] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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Høgsberg IM, Nielsen MM, Cold S, Rose C. [Chemotherapy in metastasing breast cancer--is it beneficial?]. Ugeskr Laeger 1994; 156:6549-6550. [PMID: 7825256] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Carcinoma of the breast is the most common type of cancer among women in Denmark (3,000 new cases a year). About half of the patients will at some time develop metastases. Treatment of extended disease is controversial. Public discussion has focused on whether it is desirable to treat these patients with chemotherapy or not. This case story describes four cases with long term survival (nine, ten, 14, 19 years after début of metastases). This underlines that it is possible within the existing types of treatment to achieve both extended survival and acceptable life quality. The doctor's dilemma is that he does not know whom treatment helps. We conclude that treatment should be offered to all patients. This will be of benefit to the whole group.
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Affiliation(s)
- I M Høgsberg
- Onkologisk Afdeling R, Odense Universitetshospital
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Burchhardt J, Nielsen MM, Adams DL, Lundgren E, Andersen JN. Structure of Al(111)-( sqrt 3 x sqrt 3 )R30 degrees-Na: A LEED study. Phys Rev B Condens Matter 1994; 50:4718-4724. [PMID: 9976780 DOI: 10.1103/physrevb.50.4718] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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Nielsen MM, Burchhardt J, Adams DL, Lundgren E, Andersen JN. Enhanced surface vibrations and reconstruction of the Al(111) surface induced by Rb adsorption. Phys Rev Lett 1994; 72:3370-3373. [PMID: 10056181 DOI: 10.1103/physrevlett.72.3370] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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Aminpirooz S, Schmalz A, Becker L, Pangher N, Haase J, Nielsen MM, Batchelor DR, Bogh E, Adams DL. Temperature-dependent local geometries in the system Al(100)-c(2 x 2)-Na: A surface extended x-ray-absorption fine-structure study. Phys Rev B Condens Matter 1992; 46:15594-15597. [PMID: 10003698 DOI: 10.1103/physrevb.46.15594] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/12/2023]
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Abstract
BACKGROUND AND PURPOSE Dichloroacetate facilitates a decrease in brain lactate during reperfusion after incomplete ischemia. This study examined the possible activation of pyruvate dehydrogenase enzyme by dichloroacetate to explain this effect. Because the duration of ischemia and hyperglycemia exacerbate ischemic brain damage, the effect of both of these factors on lactate reduction with and without dichloroacetate treatment after ischemia also was explored. METHODS The two-vessel occlusion and controlled blood loss model of stroke was applied to anesthetized rats. Samples of cerebral cortex were analyzed for lactate by enzyme fluorometry and for pyruvate dehydrogenase activity by radioassay. RESULTS Treatment with dichloroacetate produced no significant stimulation of pyruvate dehydrogenase after ischemia. When the duration of ischemia was increased or 50% glucose was infused before ischemia, brain lactate was significantly higher (p less than 0.01, Duncan's test). After 30 minutes of ischemia, treatment with a low dose of dichloroacetate (25 mg/kg) improved the reduction in lactate (p less than 0.01, Duncan's test). CONCLUSIONS These results indicate that although dichloroacetate reduces brain lactate after cerebral ischemia, the mechanism of action does not involve dichloroacetate's known ability to stimulate pyruvate dehydrogenase. However, these data support the use of dichloroacetate to lower cerebral lactate, especially in cases where ischemia is greater than or equal to 30 minutes in duration. They also suggest that early restoration and maintenance of perfusion after ischemia and discontinuing the use of 50% glucose before impending ischemia likewise would facilitate reduction of postischemic brain lactate.
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Affiliation(s)
- R V Dimlich
- Department of Emergency Medicine, College of Medicine, University of Cincinnati, OH 45267-0769
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Nielsen MM. Logistical implementation of cholesterol screening at the worksite. Appointment versus walk-in approach. AAOHN J 1991; 39:235-40. [PMID: 2025334] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Worksite cholesterol screening programs providing initial cholesterol screening, dietary consultation, and follow up evaluation are an excellent way to assist individuals to know their cholesterol. Two methods for implementation of cholesterol screening at the worksite include walk-in and appointment. These methods can be tailored to accommodate any worksite population. Guidelines for planning, implementation, follow-up, and evaluation of cholesterol screening programs are discussed.
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Keiding S, Freund L, Hobolth N, Holsteen V, Mac Intyre BH, Kirkegaard P, Nielsen MM, Rokkjaer M, Schaffalitzky de Muckadell OB, Skovby F. [Liver transplantation undertaken on Danes abroad]. Ugeskr Laeger 1989; 151:360-2. [PMID: 2645735] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
The indication for liver transplantation is the end stage of liver disease. Liver transplantations are not carried out in Denmark at present, one of the reasons being that it requires introduction of the brain death criterion, because the donor liver must be removed during maintained circulation. To date (November 1988), liver transplantations have been carried out abroad on seven Danes. One of these died after operation, one has chronic rejection and is to have retransplantation while the remaining five patients are well. In Europe (including Sweden, Norway and Finland) and USA, more than 5,000 patients have been liver transplanted. The one-year survival is approximately 75%. After this, only few liver-related deaths occur and the majority of patients can resume their previous activities. A total of 18 Danes have been assessed in transplantation centres abroad: Two are waiting for transplantation in the near future and seven have been accepted for transplantation at a later date, depending on the course of the disease. In a number of Danes, liver transplantation has been considered indicated but has not been effectuated because the disease was so advanced at the time of referral, that the patient died before transfer or the patient did not desire operation abroad.
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Illum N, Nielsen MM, Christensen E, Thelle T. [Lesch-Nyhan syndrome]. Ugeskr Laeger 1988; 150:2320-2. [PMID: 3206596] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
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Abstract
Five children, admitted with acute psychotic reactions after use of Scopolamine eye drops 0.2%, are presented. The predominant symptoms were visual hallucinations, strange behaviour, and restlessness. In one case peripheral symptoms were observed. Recovery was complete in 24 h. Prescription of Scopolamine eye drops should be followed by information of possible adverse effects. Cyclopentolate might be used instead.
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Nielsen MM, Hall FT, Monsen ER, Worthington B. Eating quality, nutritive value, and cost of ground round and hamburger. J Am Diet Assoc 1967; 50:201-3. [PMID: 6020003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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