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Macion A, Schäfer R. Ionization potentials of metal clusters studied with a broad range, tunable vacuum ultraviolet light source. Rev Sci Instrum 2023; 94:063101. [PMID: 37862487 DOI: 10.1063/5.0151238] [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] [Subscribe] [Scholar Register] [Received: 03/20/2023] [Accepted: 05/11/2023] [Indexed: 10/22/2023]
Abstract
In this work, we present an alternative to complex laser setups or synchrotron light sources to accurately measure the ionization potentials of metal clusters. The setup is based on a commercial Xe flash lamp, combined with a vacuum monochromator, and has been applied to determine the ionization potentials of Snn clusters with n = 8-12 atoms. The uncertainty in the determination of the ionization potentials is mainly caused by the bandwidth of the monochromator. The adiabatic ionization potentials (AIPs) are extracted from experimental photoionization efficiency curves. Franck-Condon simulations are additionally used to interpret the shape and onset of the photo-ion yield. The obtained AIPs are (all energies are in eV) Sn8 (6.53 ± 0.05), Sn9 (6.69 ± 0.04), Sn10 (6.93 ± 0.03), Sn11 (6.34 ± 0.05), and Sn12 (IsoI 6.64 ± 0.04 and IsoIII 6.36 ± 0.05). Furthermore, the impact of multiple isomers present in the experiment on the photo-ion yield is addressed and compared with other experimental data in the literature.
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Affiliation(s)
- A Macion
- Technical University of Darmstadt, Eduard-Zintl-Institut, Alarich-Weiss-Straße 8, 64287 Darmstadt, Germany
| | - R Schäfer
- Technical University of Darmstadt, Eduard-Zintl-Institut, Alarich-Weiss-Straße 8, 64287 Darmstadt, Germany
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2
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Motta S, Christensen JB, Togno M, Schäfer R, Safai S, Lomax AJ, Yukihara EG. Characterization of LiF:Mg,Ti thermoluminescence detectors in low-LET proton beams at ultra-high dose rates. Phys Med Biol 2023; 68. [PMID: 36696696 DOI: 10.1088/1361-6560/acb634] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2022] [Accepted: 01/25/2023] [Indexed: 01/26/2023]
Abstract
Objective.This work aims at characterizing LiF:Mg,Ti thermoluminescence detectors (TLDs) for dosimetry of a 250 MeV proton beam delivered at ultra-high dose rates (UHDR). Possible dose rate effects in LiF:Mg,Ti, as well as its usability for dosimetry of narrow proton beams are investigated.Approach.LiF:Mg,Ti (TLD-100TMMicrocubes, 1 mm × 1 mm × 1 mm) was packaged in matrices of 5 × 5 detectors. The center of each matrix was irradiated with single-spot low-LET (energy >244 MeV) proton beam in the (1-4500) Gy s-1average dose rates range. A beam reconstruction procedure was applied to the detectors irradiated at the highest dose rate (Gaussian beam sigma <2 mm) to correct for volumetric averaging effects. Reference dosimetry was carried out with a diamond detector and radiochromic films. The delivered number of protons was measured by a Faraday cup, which was employed to normalize the detector responses.Main results.The lateral beam spread obtained from the beam reconstruction agreed with the one derived from the radiochromic film measurements. No dose rates effects were observed in LiF:Mg,Ti for the investigated dose rates within 3% (k= 1). On average, the dose response of the TLDs agreed with the reference detectors within their uncertainties. The largest deviation (-5%) was measured at 4500 Gy s-1.Significance.The dose rate independence of LiF:Mg,Ti TLDs makes them suitable for dosimetry of UHDR proton beams. Additionally, the combination of a matrix of TLDs and the beam reconstruction can be applied to determine the beam profile of narrow proton beams.
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Affiliation(s)
- S Motta
- Department of Radiation Safety and Security, Paul Scherrer Institute, Villigen PSI, Switzerland.,Department of Physics, ETH Zürich, Zürich, Switzerland
| | - J B Christensen
- Department of Radiation Safety and Security, Paul Scherrer Institute, Villigen PSI, Switzerland
| | - M Togno
- Center for Proton Therapy, Paul Scherrer Institute, Villigen PSI, Switzerland
| | - R Schäfer
- Center for Proton Therapy, Paul Scherrer Institute, Villigen PSI, Switzerland
| | - S Safai
- Center for Proton Therapy, Paul Scherrer Institute, Villigen PSI, Switzerland
| | - A J Lomax
- Center for Proton Therapy, Paul Scherrer Institute, Villigen PSI, Switzerland.,Department of Physics, ETH Zürich, Zürich, Switzerland
| | - E G Yukihara
- Department of Radiation Safety and Security, Paul Scherrer Institute, Villigen PSI, Switzerland
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3
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Togno M, Nesteruk KP, Schäfer R, Psoroulas S, Meer D, Grossmann M, Christensen JB, Yukihara EG, Lomax AJ, Weber DC, Safai S. Ultra-high dose rate dosimetry for pre-clinical experiments with mm-small proton fields. Phys Med 2022; 104:101-111. [PMID: 36395638 DOI: 10.1016/j.ejmp.2022.10.019] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/07/2022] [Revised: 10/10/2022] [Accepted: 10/23/2022] [Indexed: 11/15/2022] Open
Abstract
PURPOSE To characterize an experimental setup for ultra-high dose rate (UHDR) proton irradiations, and to address the challenges of dosimetry in millimetre-small pencil proton beams. METHODS At the PSI Gantry 1, high-energy transmission pencil beams can be delivered to biological samples and detectors up to a maximum local dose rate of ∼9000 Gy/s. In the presented setup, a Faraday cup is used to measure the delivered number of protons up to ultra-high dose rates. The response of transmission ion-chambers, as well as of different field detectors, was characterized over a wide range of dose rates using the Faraday cup as reference. RESULTS The reproducibility of the delivered proton charge was better than 1 % in the proposed experimental setup. EBT3 films, Al2O3:C optically stimulated luminescence detectors and a PTW microDiamond were used to validate the predicted dose. Transmission ionization chambers showed significant volume ion-recombination (>30 % in the tested conditions) which can be parametrized as a function of the maximum proton current density. Over the considered range, EBT3 films, inorganic scintillator-based screens and the PTW microDiamond were demonstrated to be dose rate independent within ±3 %, ±1.8 % and ±1 %, respectively. CONCLUSIONS Faraday cups are versatile dosimetry instruments that can be used for dose estimation, field detector characterization and on-line dose verification for pre-clinical experiments in UHDR proton pencil beams. Among the tested detectors, the commercial PTW microDiamond was found to be a suitable option to measure real time the dosimetric properties of narrow pencil proton beams for dose rates up to 2.2 kGy/s.
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Affiliation(s)
- M Togno
- Center for Proton Therapy, Paul Scherrer Institut, Villigen, Switzerland.
| | - K P Nesteruk
- Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, USA
| | - R Schäfer
- Center for Proton Therapy, Paul Scherrer Institut, Villigen, Switzerland
| | - S Psoroulas
- Center for Proton Therapy, Paul Scherrer Institut, Villigen, Switzerland
| | - D Meer
- Center for Proton Therapy, Paul Scherrer Institut, Villigen, Switzerland
| | - M Grossmann
- Center for Proton Therapy, Paul Scherrer Institut, Villigen, Switzerland
| | - J B Christensen
- Department of Radiation Safety and Security, Paul Scherrer Institut, Villigen, Switzerland
| | - E G Yukihara
- Department of Radiation Safety and Security, Paul Scherrer Institut, Villigen, Switzerland
| | - A J Lomax
- Center for Proton Therapy, Paul Scherrer Institut, Villigen, Switzerland; Department of Physics, ETH Zurich, Zurich, Switzerland
| | - D C Weber
- Center for Proton Therapy, Paul Scherrer Institut, Villigen, Switzerland; Department of Radiation Oncology, University Hospital Zurich, Zurich, Switzerland; Department of Radiation Oncology, Inselspital, Bern University Hospital, University of Bern, Switzerland
| | - S Safai
- Center for Proton Therapy, Paul Scherrer Institut, Villigen, Switzerland
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4
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Leyvraz S, Schütte M, Kessler T, Lamping M, Burock S, Ochsenreither S, Amstislavskiy V, Risch T, Jelas I, Ulrich C, Dobos G, Klauschen F, Schäfer R, Lange B, Klinghammer K, Yaspo ML, Keilholz U. 847P Precision oncology for resistant acral, mucosal and cutaneous melanomas: A prospective broad high throughput genomics feasibility study. Ann Oncol 2022. [DOI: 10.1016/j.annonc.2022.07.973] [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: 11/25/2022] Open
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5
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Hu B, Lelek S, Spanjaard B, El-Sammak H, Simões MG, Mintcheva J, Aliee H, Schäfer R, Meyer AM, Theis F, Stainier DYR, Panáková D, Junker JP. Origin and function of activated fibroblast states during zebrafish heart regeneration. Nat Genet 2022; 54:1227-1237. [PMID: 35864193 PMCID: PMC7613248 DOI: 10.1038/s41588-022-01129-5] [Citation(s) in RCA: 31] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2022] [Accepted: 06/09/2022] [Indexed: 12/12/2022]
Abstract
The adult zebrafish heart has a high capacity for regeneration following injury. However, the composition of the regenerative niche has remained largely elusive. Here, we dissected the diversity of activated cell states in the regenerating zebrafish heart based on single-cell transcriptomics and spatiotemporal analysis. We observed the emergence of several transient cell states with fibroblast characteristics following injury, and we outlined the proregenerative function of collagen-12-expressing fibroblasts. To understand the cascade of events leading to heart regeneration, we determined the origin of these cell states by high-throughput lineage tracing. We found that activated fibroblasts were derived from two separate sources: the epicardium and the endocardium. Mechanistically, we determined Wnt signalling as a regulator of the endocardial fibroblast response. In summary, our work identifies specialized activated fibroblast cell states that contribute to heart regeneration, thereby opening up possible approaches to modulating the regenerative capacity of the vertebrate heart. Single-cell RNA sequencing and spatiotemporal analysis of the regenerating zebrafish heart identify transient proregenerative fibroblast-like cells that are derived from the epicardium and the endocardium. Wnt signalling regulates the endocardial fibroblast response.
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Affiliation(s)
- Bo Hu
- Max Delbrück Center for Molecular Medicine in the Helmholtz Association, Berlin Institute for Medical Systems Biology, Berlin, Germany
| | - Sara Lelek
- Max Delbrück Center for Molecular Medicine in the Helmholtz Association, Berlin, Germany.,DZHK (German Centre for Cardiovascular Research) partner site, Berlin, Germany
| | - Bastiaan Spanjaard
- Max Delbrück Center for Molecular Medicine in the Helmholtz Association, Berlin Institute for Medical Systems Biology, Berlin, Germany
| | - Hadil El-Sammak
- Department of Developmental Genetics, Max Planck Institute for Heart and Lung Research, Bad Nauheim, Germany.,DZHK (German Centre for Cardiovascular Research) partner site Rhine/Main, Frankfurt, Germany
| | - Mariana Guedes Simões
- Max Delbrück Center for Molecular Medicine in the Helmholtz Association, Berlin, Germany
| | - Janita Mintcheva
- Max Delbrück Center for Molecular Medicine in the Helmholtz Association, Berlin Institute for Medical Systems Biology, Berlin, Germany
| | - Hananeh Aliee
- Helmholtz Center Munich - German Research Center for Environmental Health, Institute of Computational Biology, Neuherberg, Munich, Germany
| | - Ronny Schäfer
- Max Delbrück Center for Molecular Medicine in the Helmholtz Association, Berlin Institute for Medical Systems Biology, Berlin, Germany
| | - Alexander M Meyer
- Max Delbrück Center for Molecular Medicine in the Helmholtz Association, Berlin, Germany
| | - Fabian Theis
- Helmholtz Center Munich - German Research Center for Environmental Health, Institute of Computational Biology, Neuherberg, Munich, Germany
| | - Didier Y R Stainier
- Department of Developmental Genetics, Max Planck Institute for Heart and Lung Research, Bad Nauheim, Germany.,DZHK (German Centre for Cardiovascular Research) partner site Rhine/Main, Frankfurt, Germany
| | - Daniela Panáková
- Max Delbrück Center for Molecular Medicine in the Helmholtz Association, Berlin, Germany. .,DZHK (German Centre for Cardiovascular Research) partner site, Berlin, Germany.
| | - Jan Philipp Junker
- Max Delbrück Center for Molecular Medicine in the Helmholtz Association, Berlin Institute for Medical Systems Biology, Berlin, Germany. .,DZHK (German Centre for Cardiovascular Research) partner site, Berlin, Germany.
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Borsato M, Cid Vidal X, Tsai Y, Vázquez Sierra C, Zurita J, Alonso-Álvarez G, Boyarsky A, Brea Rodríguez A, Buarque Franzosi D, Cacciapaglia G, Casais Vidal A, Du M, Elor G, Escudero M, Ferretti G, Flacke T, Foldenauer P, Hajer J, Henry L, Ilten P, Kamenik J, Kishor Jashal B, Knapen S, Kostiuk I, Redi FL, Low M, Liu Z, Oyanguren Campos A, Polycarpo E, Ramos M, Ramos Pernas M, Salvioni E, Rangel MS, Schäfer R, Sestini L, Soreq Y, Tran VQ, Timiryasov I, van Veghel M, Westhoff S, Williams M, Zupan J. Unleashing the full power of LHCb to probe stealth new physics. Rep Prog Phys 2022; 85:024201. [PMID: 34942603 DOI: 10.1088/1361-6633/ac4649] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/25/2021] [Accepted: 12/23/2021] [Indexed: 06/14/2023]
Abstract
In this paper, we describe the potential of the LHCb experiment to detect stealth physics. This refers to dynamics beyond the standard model that would elude searches that focus on energetic objects or precision measurements of known processes. Stealth signatures include long-lived particles and light resonances that are produced very rarely or together with overwhelming backgrounds. We will discuss why LHCb is equipped to discover this kind of physics at the Large Hadron Collider and provide examples of well-motivated theoretical models that can be probed with great detail at the experiment.
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Affiliation(s)
- M Borsato
- Physikalisches Institut, Ruprecht-Karls-Universität Heidelberg, Heidelberg, Germany
| | - X Cid Vidal
- Instituto Galego de Física de Altas Enerxías (IGFAE), Universidade de Santiago de Compostela, Santiago de Compostela, Spain
| | - Y Tsai
- Maryland Center for Fundamental Physics, Department of Physics, University of Maryland, College Park, MD 20742-4111, United States of America
- Department of Physics, University of Notre Dame, South Bend, IN 46556, United States of America
| | - C Vázquez Sierra
- European Organization for Nuclear Research (CERN), Geneva, Switzerland
| | - J Zurita
- Instituto de Física Corpuscular (CSIC-UV), Valencia, Spain
| | - G Alonso-Álvarez
- Department of Physics & McGill Space Institute, McGill University, 3600 Rue University, Montréal, QC, H3A 2T8, Canada
| | - A Boyarsky
- Intituut-Lorentz, Leiden University, 2333 CA Leiden, The Netherlands
| | - A Brea Rodríguez
- Instituto Galego de Física de Altas Enerxías (IGFAE), Universidade de Santiago de Compostela, Santiago de Compostela, Spain
| | - D Buarque Franzosi
- Department of Physics, Chalmers University of Technology, Fysikgården, 41296 Göteborg, Sweden
- Physics Department, University of Gothenburg, 41296 Göteborg, Sweden
| | - G Cacciapaglia
- University of Lyon, Université Claude Bernard Lyon 1, F-69001 Lyon, France
- Institut de Physique des 2 Infinis (IP2I) de Lyon, CNRS/UMR5822, F-69622 Villeurbanne, France
| | - A Casais Vidal
- Instituto Galego de Física de Altas Enerxías (IGFAE), Universidade de Santiago de Compostela, Santiago de Compostela, Spain
| | - M Du
- Department of Physics, Nanjing University, Nanjing 210093, People's Republic of China
| | - G Elor
- Department of Physics, University of Washington, Seattle, WA 98195, United States of America
| | - M Escudero
- Physik-Department, Technische Universität, München, James-Franck-Straße, 85748 Garching, Germany
| | - G Ferretti
- Department of Physics, Chalmers University of Technology, Fysikgården, 41296 Göteborg, Sweden
| | - T Flacke
- Center for Theoretical Physics of the Universe, Institute for Basic Science (IBS), Daejeon 34126, Republic of Korea
| | - P Foldenauer
- Institute for Particle Physics Phenomenology, Durham University, Durham DH1 3LE, United Kingdom
| | - J Hajer
- Centre for Cosmology, Particle Physics and Phenomenology, Université catholique de Louvain, Louvain-la-Neuve B-1348, Belgium
- Department of Physics, Universität Basel, Klingelbergstraße 82, CH-4056 Basel, Switzerland
| | - L Henry
- European Organization for Nuclear Research (CERN), Geneva, Switzerland
- Instituto de Física Corpuscular (CSIC-UV), Valencia, Spain
- INFN Sezione di Milano, Milano, Italy
| | - P Ilten
- Department of Physics, University of Cincinnati, Cincinnati, Ohio 45221, United States of America
| | - J Kamenik
- Jožef Stefan Institute, Jamova 39, 1000 Ljubljana, Slovenia
- Faculty of Mathematics and Physics, University of Ljubljana, Jadranska 19, 1000 Ljubljana, Slovenia
| | | | - S Knapen
- European Organization for Nuclear Research (CERN), Geneva, Switzerland
| | - Igor Kostiuk
- Nikhef National Institute for Subatomic Physics, Amsterdam, The Netherlands
| | - F L Redi
- Institute of Physics, Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland
| | - M Low
- Theoretical Physics Department, Fermilab, PO Box 500, Batavia, IL 60510, United States of America
| | - Z Liu
- Department of Physics, Nanjing University, Nanjing 210093, People's Republic of China
- Center for High Energy Physics, Peking University, Beijing 100871, People's Republic of China
- CAS Center for Excellence in Particle Physics, Beijing 100049, People's Republic of China
| | | | - E Polycarpo
- Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, Brazil
| | - M Ramos
- CAFPE and Departamento de Física Teórica y del Cosmos, Universidad de Granada, Campus de Fuentenueva, E-18071 Granada, Spain
- Laboratório de Instrumentaçao e Física Experimental de Partículas, Departamento de Física da Universidade do Minho, Campus de Gualtar, 4710-057 Braga, Portugal
| | - M Ramos Pernas
- Department of Physics, University of Warwick, Coventry, United Kingdom
| | - E Salvioni
- European Organization for Nuclear Research (CERN), Geneva, Switzerland
| | - M S Rangel
- Universidade Federal do Rio de Janeiro (UFRJ), Rio de Janeiro, Brazil
| | - R Schäfer
- Institute for Theoretical Physics, Heidelberg University, 69120 Heidelberg, Germany
| | - L Sestini
- Istituto Nazionale di Fisica Nucleare (INFN), Padova Division, Padova, Italy
| | - Y Soreq
- Physics Department, Technion-Israel Institute of Technology, Haifa 3200003, Israel
| | - V Q Tran
- Department of Physics, Nanjing University, Nanjing 210093, People's Republic of China
| | - I Timiryasov
- Institute of Physics, Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland
| | - M van Veghel
- Van Swinderen Institute, University of Groningen, Groningen, The Netherlands
| | - S Westhoff
- Institute for Theoretical Physics, Heidelberg University, 69120 Heidelberg, Germany
| | - M Williams
- Laboratory for Nuclear Science, Massachusetts Institute of Technology, Cambridge, MA 02139, United States of America
| | - J Zupan
- Department of Physics, University of Cincinnati, Cincinnati, Ohio 45221, United States of America
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7
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Willer H, Thielemann C, Elvers-Hornung S, Spohn G, Delorme, Giesen M, Schäfer R, Bieback K. Repeated administration of human bone marrow derived MSC expanded in virally inactivated human platelet lysate improves wound healing in diabetic rats. Cytotherapy 2021. [DOI: 10.1016/s1465324921003406] [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: 11/30/2022]
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8
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Schmidt T, Schlander D, Jüchter V, Baranyai J, Neuberger F, Schäfer R. Design of a compact and versatile radiation heater with an additively manufactured Nb radiation shield for UHV high-temperature sample preparation. Rev Sci Instrum 2021; 92:025111. [PMID: 33648129 DOI: 10.1063/5.0023982] [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] [Subscribe] [Scholar Register] [Received: 08/03/2020] [Accepted: 01/29/2021] [Indexed: 06/12/2023]
Abstract
A compact, ultrahigh vacuum, radiative heater based on pyrolytic boron nitride that efficiently directs nearly all of its radiation to the sample was designed and constructed. It is shown that the heater reaches temperatures of 1300 K experimentally at 60% of its maximum power. A COMSOL Multiphysics® simulation and an analytical model predict an ultimate temperature of up to 1500 K. Furthermore, the heater does not introduce any contamination to the sample. This is accomplished by a custom-made Nb radiation shield, which was manufactured by selective laser melting and holds a flag-style sample holder. Before manufacturing, the whole assembly was simulated with COMSOL Multiphysics to validate the design of the radiation shield.
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Affiliation(s)
- T Schmidt
- Eduard-Zintl-Institut, TU Darmstadt, 64287 Darmstadt, Germany
| | - D Schlander
- Eduard-Zintl-Institut, TU Darmstadt, 64287 Darmstadt, Germany
| | - V Jüchter
- Heraeus Additive Manufacturing GmbH, 63405 Hanau, Germany
| | - J Baranyai
- Eduard-Zintl-Institut, TU Darmstadt, 64287 Darmstadt, Germany
| | - F Neuberger
- Eduard-Zintl-Institut, TU Darmstadt, 64287 Darmstadt, Germany
| | - R Schäfer
- Eduard-Zintl-Institut, TU Darmstadt, 64287 Darmstadt, Germany
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9
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Moreno-Ayala R, Olivares-Chauvet P, Schäfer R, Junker JP. Variability of an Early Developmental Cell Population Underlies Stochastic Laterality Defects. Cell Rep 2021; 34:108606. [PMID: 33440143 PMCID: PMC7809618 DOI: 10.1016/j.celrep.2020.108606] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2020] [Revised: 10/28/2020] [Accepted: 12/15/2020] [Indexed: 12/11/2022] Open
Abstract
Embryonic development seemingly proceeds with almost perfect precision. However, it is largely unknown how much underlying microscopic variability is compatible with normal development. Here, we quantify embryo-to-embryo variability in vertebrate development by studying cell number variation in the zebrafish endoderm. We notice that the size of a sub-population of the endoderm, the dorsal forerunner cells (DFCs, which later form the left-right organizer), exhibits significantly more embryo-to-embryo variation than the rest of the endoderm. We find that, with incubation of the embryos at elevated temperature, the frequency of left-right laterality defects is increased drastically in embryos with a low number of DFCs. Furthermore, we observe that these fluctuations have a large stochastic component among fish of the same genetic background. Hence, a stochastic variation in early development leads to a remarkably strong macroscopic phenotype. These fluctuations appear to be associated with maternal effects in the specification of the DFCs. High embryo-to-embryo variability of dorsal forerunner cell numbers Fluctuations of dorsal forerunner cells have a large stochastic component Embryos with fewer dorsal forerunner cells frequently develop laterality defects Variability of dorsal forerunner cell numbers is associated to maternal effects
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Affiliation(s)
- Roberto Moreno-Ayala
- Max Delbrück Center for Molecular Medicine, Berlin Institute for Medical Systems Biology, Hannoversche Strasse 28, 10115 Berlin, Germany
| | - Pedro Olivares-Chauvet
- Max Delbrück Center for Molecular Medicine, Berlin Institute for Medical Systems Biology, Hannoversche Strasse 28, 10115 Berlin, Germany
| | - Ronny Schäfer
- Max Delbrück Center for Molecular Medicine, Berlin Institute for Medical Systems Biology, Hannoversche Strasse 28, 10115 Berlin, Germany
| | - Jan Philipp Junker
- Max Delbrück Center for Molecular Medicine, Berlin Institute for Medical Systems Biology, Hannoversche Strasse 28, 10115 Berlin, Germany.
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10
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Lorenz KW, Schäfer R. [TEG-guided treatment of a dabigatran overdose in a patient with acute kidney failure]. Anaesthesist 2020; 69:573-578. [PMID: 32564188 DOI: 10.1007/s00101-020-00801-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2020] [Revised: 04/30/2020] [Accepted: 05/16/2020] [Indexed: 11/25/2022]
Abstract
This article presents the case of a multimorbid male patient with an accidental dabigatran overdose caused by kidney failure in the context of an acute intestinal disorder. After effective initial antagonizing of the dabigatran effect using idarucizumab a dabigatran rebound was detected caused by a single hemodialysis leading to a severe intrapulmonary hemorrhage. As dabigatran plasma level testing was not available and conventional coagulation analysis was out of interpretable range due to the impact of dabigatran, continuous thrombelastography (TEG) was used to detect the effect of dabigatran and monitor the treatment results. The most significant parameter used in the kaolin activated clotting time was the R‑time parameter, which was massively prolonged by the interrupted coagulation cascade.
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Affiliation(s)
- K-W Lorenz
- Klinik für Anästhesie, operative Intensiv- und Palliativmedizin, Klinikum Würzburg Mitte - Standort Juliusspital, Juliuspromenade 19, 97070, Würzburg, Deutschland.
| | - R Schäfer
- Klinik für Anästhesie, operative Intensiv- und Palliativmedizin, Klinikum Würzburg Mitte - Standort Juliusspital, Juliuspromenade 19, 97070, Würzburg, Deutschland
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11
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Schäfer R. [RAS mutations at the molecular tumor conference]. Pathologe 2019; 40:355-359. [PMID: 31754788 DOI: 10.1007/s00292-019-00702-w] [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] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Members of the rat sarcoma (RAS) gene family belong to the most frequently mutated genes that drive pathogenesis and therapy response. As the discovery of their malignant potential dates back more than three decades, cellular mutated RAS genes and their products belong to the best characterized cancer genes. Despite urgent clinical needs, RAS therapies are still elusive and limited to preclinical studies. However, very recently, novel and promising approaches have become a reality in clinical applications and trials. In the near future, interesting therapeutic options will emerge that are capable of targeting "undruggable" RAS. This will be even more important as the detection of RAS mutations has already been an integral part of routine molecular diagnostics for many years.
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Affiliation(s)
- R Schäfer
- Comprehensive Cancer Center, Charité - Universitätsmedizin Berlin, Charitéplatz 1, 10117, Berlin, Deutschland.
- Deutsches Krebsforschungszentrum Heidelberg, Deutsches Konsortium für Translationale Krebsforschung (DKTK), Heidelberg, Deutschland.
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12
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Janssen G, Pourhassan M, Lenzen-Großimlinghaus R, Jäger M, Schäfer R, Spamer C, Cuvelier I, Volkert D, Wirth R. The Refeeding Syndrome revisited: you can only diagnose what you know. Eur J Clin Nutr 2019; 73:1458-1463. [PMID: 31127188 DOI: 10.1038/s41430-019-0441-x] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2019] [Revised: 05/10/2019] [Accepted: 05/13/2019] [Indexed: 02/08/2023]
Abstract
BACKGROUND/OBJECTIVES The Refeeding Syndrome (RFS) is a serious complication in patients receiving nutrition support after a period of severe malnutrition. We frequently recognize and diagnose the RFS due to increased awareness. Thus, we observe that many physicians do not know the RFS and that it is rarely diagnosed. The aim of the study was to determine whether physicians in Germany know the RFS. SUBJECTS/METHODS A questionnaire with a case vignette about an older person who developed the RFS after initiation of nutritional therapy was submitted to German physicians and fifth year medical students, who were participants of educational lectures. RESULTS Of the 281 participants who answered the respective question, 40 participants (14%) correctly diagnosed the RFS of the case vignette and 21 participants (8%) gave nearly correct answers. Indeed, the majority of the participants did not diagnose the RFS. CONCLUSIONS Although the RFS may lead to fatal complications, it is unknown to the majority of the queried physicians. Therefore, there is a call to implement the RFS in respective curricula and increase systematic education on this topic.
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Affiliation(s)
- G Janssen
- Department for Geriatric Medicine, Marien Hospital Herne - University Hospital, Ruhr-Universität Bochum, Herne, Germany
| | - M Pourhassan
- Department for Geriatric Medicine, Marien Hospital Herne - University Hospital, Ruhr-Universität Bochum, Herne, Germany
| | | | - M Jäger
- Hüttenhospital, Dortmund, Germany
| | - R Schäfer
- GFO Kliniken Rhein-Berg, Bergisch Gladbach, Germany
| | | | - I Cuvelier
- Department of Geriatric Medicine, ViDia Christliche Kliniken Karlsruhe, Karlsruhe, Germany
| | - D Volkert
- Institute for Biomedicine of Aging, Friedrich-Alexander-Universität Erlangen-Nürnberg, Nürnberg, Germany
| | - R Wirth
- Department for Geriatric Medicine, Marien Hospital Herne - University Hospital, Ruhr-Universität Bochum, Herne, Germany.
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13
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14
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Khong S, Lee M, Khong D, Kosaric N, Duscher D, Dong Y, Schäfer R, Gurtner G. 1407 Single-cell transcriptomics of human mesenchymal stem cells reveal age-related cellular subpopulation depletion and impaired regenerative gene expression. J Invest Dermatol 2018. [DOI: 10.1016/j.jid.2018.03.1425] [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: 11/25/2022]
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15
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Schäfer R, Strnad V, Polgár C, Uter W, Hildebrandt G, Ott O, Kauer-Dorner D, Knauerhase H, Major T, Lyczek J, Guinot J, Dunst J, Gutierrez Miguelez C, Slampa P, Allgäuer M, Lössl K, Kovacs G, Fietkau R, Resch A, Kulik A, Arribas L, Niehoff P, Guedea F, Gall C, Polat B. OC-0326: QOL After APBI (Multicatheter Brachytherapy) Versus WBI: 5-Year Results, Phase 3 GEC-ESTRO Trial. Radiother Oncol 2018. [DOI: 10.1016/s0167-8140(18)30636-4] [Citation(s) in RCA: 1] [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: 11/29/2022]
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16
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Shayeghi A, Pašteka LF, Götz DA, Schwerdtfeger P, Schäfer R. Spin–orbit effects in optical spectra of gold–silver trimers. Phys Chem Chem Phys 2018; 20:9108-9114. [DOI: 10.1039/c8cp00672e] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [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
Photodissociation spectra of cationic gold–silver trimers are analysed using relativistic electronic structure theories paying special attention to the importance of spin–orbit and charge transfer effects.
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Affiliation(s)
- A. Shayeghi
- Vienna Center for Quantum Science and Technology
- Faculty of Physics
- University of Vienna
- A-1090 Vienna
- Austria
| | - L. F. Pašteka
- Centre for Theoretical Chemistry and Physics
- The New Zealand Institute for Advanced Study
- Massey University Auckland
- 0632 Auckland
- New Zealand
| | - D. A. Götz
- Eduard-Zintl-Institut
- Technische Universität Darmstadt
- 64287 Darmstadt
- Germany
| | - P. Schwerdtfeger
- Centre for Theoretical Chemistry and Physics
- The New Zealand Institute for Advanced Study
- Massey University Auckland
- 0632 Auckland
- New Zealand
| | - R. Schäfer
- Eduard-Zintl-Institut
- Technische Universität Darmstadt
- 64287 Darmstadt
- Germany
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17
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Strunk D, Lozano M, Marks DC, Loh YS, Gstraunthaler G, Schennach H, Rohde E, Laner-Plamberger S, Öller M, Nystedt J, Lotfi R, Rojewski M, Schrezenmeier H, Bieback K, Schäfer R, Bakchoul T, Waidmann M, Jonsdottir-Buch SM, Montazeri H, Sigurjonsson OE, Iudicone P, Fioravanti D, Pierelli L, Introna M, Capelli C, Falanga A, Takanashi M, Lόpez-Villar O, Burnouf T, Reems JA, Pierce J, Preslar AM, Schallmoser K. International Forum on GMP-grade human platelet lysate for cell propagation: summary. Vox Sang 2017; 113:80-87. [PMID: 29076169 DOI: 10.1111/vox.12593] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Affiliation(s)
- D Strunk
- Institute of Experimental and Clinical Cell Therapy, Paracelsus Medical University, Salzburg, Austria
| | - M Lozano
- Hospital Clinic, Department of Hemotherapy and Hemostasis, Hospital Clínic University of Barcelona , Barcelona, Spain
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | - K Schallmoser
- Department of Blood Group Serology and Transfusion Medicine, Paracelsus Medical University Hospital Salzburg, Salzburg, Austria
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18
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Strunk D, Lozano M, Marks DC, Loh YS, Gstraunthaler G, Schennach H, Rohde E, Laner-Plamberger S, Öller M, Nystedt J, Lotfi R, Rojewski M, Schrezenmeier H, Bieback K, Schäfer R, Bakchoul T, Waidmann M, Jonsdottir-Buch SM, Montazeri H, Sigurjonsson OE, Iudicone P, Fioravanti D, Pierelli L, Introna M, Capelli C, Falanga A, Takanashi M, López-Villar O, Burnouf T, Reems JA, Pierce J, Preslar AM, Schallmoser K. International Forum on GMP-grade human platelet lysate for cell propagation. Vox Sang 2017; 113:e1-e25. [PMID: 29071726 DOI: 10.1111/vox.12594] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Affiliation(s)
| | | | - D C Marks
- Australian Red Cross Blood Service, Research and Development, 17 O'Riordan Street, Sydney, New South Wales, 2015, Australia
| | - Y S Loh
- Australian Red Cross Blood Service, Research and Development, 17 O'Riordan Street, Sydney, New South Wales, 2015, Australia
| | - G Gstraunthaler
- Division of Physiology, Medical University Innsbruck, Schöpfstr. 41, Innsbruck, A-6020, Austria
| | - H Schennach
- Central Institute of Blood Transfusion and Immunology, University Hospital Innsbruck, Anichstr. 35, Innsbruck, A-6020, Austria
| | - E Rohde
- Department of Blood Group Serology and Transfusion Medicine, Spinal Cord Injury and Tissue Regeneration Center Salzburg, Paracelsus Medical University, Lindhofstrasse 20-22, Salzburg, 5020, Austria
| | - S Laner-Plamberger
- Department of Blood Group Serology and Transfusion Medicine, Spinal Cord Injury and Tissue Regeneration Center Salzburg, Paracelsus Medical University, Lindhofstrasse 20-22, Salzburg, 5020, Austria
| | - M Öller
- Department of Blood Group Serology and Transfusion Medicine, Spinal Cord Injury and Tissue Regeneration Center Salzburg, Paracelsus Medical University, Lindhofstrasse 20-22, Salzburg, 5020, Austria
| | - J Nystedt
- Finnish Red Cross Blood Service, Advanced Cell Therapy Centre, Kivihaantie 7, FI-00310, Helsinki, Finland
| | - R Lotfi
- Institute for Transfusion Medicine and Immunogenetics Ulm, German Red Cross Blood Service, Baden-Wuerttemberg-Hessen , University Hospital Ulm, University of Ulm, Helmholtzstr. 10, Ulm, 89081, Germany
| | - M Rojewski
- Institute for Transfusion Medicine and Immunogenetics Ulm, German Red Cross Blood Service, Baden-Wuerttemberg-Hessen , University Hospital Ulm, University of Ulm, Helmholtzstr. 10, Ulm, 89081, Germany
| | - H Schrezenmeier
- Institute for Transfusion Medicine and Immunogenetics Ulm, German Red Cross Blood Service, Baden-Wuerttemberg-Hessen , University Hospital Ulm, University of Ulm, Helmholtzstr. 10, Ulm, 89081, Germany
| | - K Bieback
- Institute of Transfusion Medicine and Immunology, Medical Faculty Mannheim, German Red Cross Blood Service Baden-Württemberg - Hessen, Heidelberg University, Friedrich-Ebert Str. 107, Mannheim, D-68167, Germany
| | - R Schäfer
- Institute for Transfusion Medicine and Immunohematology, German Red Cross Blood Donor Service Baden-Württemberg- Hessen gGmbH, Goethe-University Hospital, Sandhofstrasse 1, Frankfurt am Main, D-60528, Germany
| | - T Bakchoul
- Center for Clinical Transfusion Medicine, Otfried-Müller-Strasse 4/1, D-72076 , Tuebingen, Germany
| | - M Waidmann
- Center for Clinical Transfusion Medicine, Otfried-Müller-Strasse 4/1, D-72076 , Tuebingen, Germany
| | - S M Jonsdottir-Buch
- The Blood Bank, Landspitali University Hospital, Snorrabraut 60, 101, Reykjavik, Iceland.,Faculty of Medicine, University of Iceland, Vatnsmyrarvegur 16, 101, Reykjavik, Iceland.,Platome Biotechnology, Alfaskeid 27, 220, Hafnarfjordur, Iceland
| | - H Montazeri
- The Blood Bank, Landspitali University Hospital, Snorrabraut 60, 101, Reykjavik, Iceland.,Platome Biotechnology, Alfaskeid 27, 220, Hafnarfjordur, Iceland
| | - O E Sigurjonsson
- The Blood Bank, Landspitali University Hospital, Snorrabraut 60, 101, Reykjavik, Iceland.,Platome Biotechnology, Alfaskeid 27, 220, Hafnarfjordur, Iceland.,School of Science and Engineering, University of Reykjavik, Menntavegur 1, 101, Reykjavik, Iceland
| | - P Iudicone
- San Camillo Forlanini Hospital, Circonvallazione Gianicolense 87, Rome, 00152, Italy
| | - D Fioravanti
- San Camillo Forlanini Hospital, Circonvallazione Gianicolense 87, Rome, 00152, Italy
| | - L Pierelli
- Department of Experimental Medicine, Sapienza University, Piazzale Aldo Moro 5, Rome, 00185, Italy
| | - M Introna
- QP USS Centro di Terapia Cellulare 'G. Lanzani', USC Ematologia, ASST Papa Giovanni XXIII, Via Garibaldi 11/13, Bergamo, 24124, Italy
| | - C Capelli
- USS Centro di Terapia Cellulare 'G. Lanzani', USC Ematologia, ASST Papa Giovanni XXIII, Via Garibaldi 11/13, Bergamo, 24124, Italy
| | - A Falanga
- Division of Immunohematology and Transfusion Medicine, ASST Papa Giovanni XXIII, Piazza OMS 1, Bergamo, 24127, Italy
| | - M Takanashi
- Japanese Red Cross Blood Service Headquarters, 1-2-1 Shiba-koen, Minato-ku, Tokyo, 105-0011, Japan
| | - O López-Villar
- Department of Hematology, University Hospital of Salamanca, P/San Vicente 58-182, Salamanca, 37007, Spain
| | - T Burnouf
- Graduate Institute of Biomedical Materials and Tissue Engineering, International PhD Program in Biomedical Engineering, College of Biomedical Engineering, Taipei Medical University, 250 Wu-Shin Street, Taipei, 101, Taiwan
| | - J A Reems
- Division of Hematology and Hematologic Malignancies, Department of Medicine, University of Utah Cell Therapy and Regenerative Medicine, 675 Arapeen, Suite 300, Salt Lake City, Utah, 84108, USA
| | - J Pierce
- Division of Hematology and Hematologic Malignancies, Department of Medicine, University of Utah Cell Therapy and Regenerative Medicine, 675 Arapeen, Suite 300, Salt Lake City, Utah, 84108, USA
| | - A M Preslar
- Division of Hematology and Hematologic Malignancies, Department of Medicine, University of Utah Cell Therapy and Regenerative Medicine, 675 Arapeen, Suite 300, Salt Lake City, Utah, 84108, USA
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19
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Abstract
A new technique for contrast separation in wide-field magneto-optical Kerr microscopy is introduced. Utilizing the light from eight light emitting diodes, guided to the microscope by glass fibers and being switched synchronously with the camera exposure, domain images with orthogonal in-plane sensitivity can be displayed simultaneously at real-time, and images with pure in-plane or polar contrast can be obtained. The benefit of this new method of contrast separation is demonstrated for Permalloy films, a NdFeB sinter magnet, and a cobalt crystal. Moreover, the new technique is shown to strongly enhance the sensitivity of Kerr microscopy by eliminating parasitic contrast contributions occurring in conventional setups. A doubling of the in-plane domain contrast and a sensitivity to Kerr rotations as low as 0.6 mdeg is demonstrated.
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Affiliation(s)
- I V Soldatov
- Institute for Metallic Materials, Leibniz Institute for Solid State and Materials Research (IFW) Dresden, Helmholtzstrasse 20, D-01069 Dresden, Germany and Institute of Natural Sciences, Ural Federal University, 620002 Ekaterinburg, Russia
| | - R Schäfer
- Institute for Metallic Materials, Leibniz Institute for Solid State and Materials Research (IFW) Dresden, Helmholtzstrasse 20, D-01069 Dresden, Germany and Institute for Materials Science, TU Dresden, 01062 Dresden, Germany
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20
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Elger B, Schmidt T, Krähling S, Neuberger F, Schäfer R. Electrostatic simulation of a complete cluster deposition apparatus. Rev Sci Instrum 2017; 88:063303. [PMID: 28667987 DOI: 10.1063/1.4984968] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
A complete electrostatic model of a cluster deposition apparatus is presented using SIMION. It consists of fifteen different ion optical components including a quadrupole mass filter and a quadrupole ion deflector. The accuracy of the model was tested by comparing calculated cationic cluster transmissions with experimental ion currents by varying the electrostatic potential of different components. Considering the negatively charged particles produced by the magnetron cluster source as a charged background with a density of 5⋅10-7 cm-3, the influence of the first components on cluster transmission is well reproduced in comparison to the experimental results. This background was included by increasing the charge of the clusters from zero to an elementary charge using a sigmoidal function. The inflection point of this function was found to depend on the first components' electrostatic potential but in good approximation, not on later ones. All of the calculated transmissions represent the experimental data quite well; therefore, the simulation is validated and helps us to understand the influence of the electrostatic components on cluster transmission and improve the target efficiency. Furthermore, this understanding opens the possibility for a global optimization scheme to be employed in the ion optics' geometries.
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Affiliation(s)
- B Elger
- Eduard-Zintl-Institut für Anorganische und Physikalische Chemie, Technische Universität Darmstadt, Alarich-Weiss-Straße 8, 64287 Darmstadt, Germany
| | - T Schmidt
- Eduard-Zintl-Institut für Anorganische und Physikalische Chemie, Technische Universität Darmstadt, Alarich-Weiss-Straße 8, 64287 Darmstadt, Germany
| | - S Krähling
- Eduard-Zintl-Institut für Anorganische und Physikalische Chemie, Technische Universität Darmstadt, Alarich-Weiss-Straße 8, 64287 Darmstadt, Germany
| | - F Neuberger
- Eduard-Zintl-Institut für Anorganische und Physikalische Chemie, Technische Universität Darmstadt, Alarich-Weiss-Straße 8, 64287 Darmstadt, Germany
| | - R Schäfer
- Eduard-Zintl-Institut für Anorganische und Physikalische Chemie, Technische Universität Darmstadt, Alarich-Weiss-Straße 8, 64287 Darmstadt, Germany
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21
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Redmer T, Walz I, Klinger B, Khouja S, Welte Y, Schäfer R, Regenbrecht C. The role of the cancer stem cell marker CD271 in DNA damage response and drug resistance of melanoma cells. Oncogenesis 2017; 6:e291. [PMID: 28112719 PMCID: PMC5294251 DOI: 10.1038/oncsis.2016.88] [Citation(s) in RCA: 49] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2016] [Revised: 10/31/2016] [Accepted: 11/25/2016] [Indexed: 12/14/2022] Open
Abstract
Several lines of evidence have suggested that stemness and acquired resistance to targeted inhibitors or chemotherapeutics are mechanistically linked. Here we observed high cell surface and total levels of nerve growth factor receptor/CD271, a marker of melanoma-initiating cells, in sub-populations of chemoresistant cell lines. CD271 expression was increased in drug-sensitive cells but not resistant cells in response to DNA-damaging chemotherapeutics etoposide, fotemustine and cisplatin. Comparative analysis of melanoma cells engineered to stably express CD271 or a targeting short hairpin RNA by expression profiling provided numerous genes regulated in a CD271-dependent manner. In-depth analysis of CD271-responsive genes uncovered the association of CD271 with regulation of DNA repair components. In addition, gene set enrichment analysis revealed enrichment of CD271-responsive genes in drug-resistant cells, among them DNA repair components. Moreover, our comparative screen identified the fibroblast growth factor 13 (FGF13) as a target of CD271, highly expressed in chemoresistant cells. Further we show that levels of CD271 determine drug response. Knock-down of CD271 in fotemustine-resistant cells decreased expression of FGF13 and at least partly restored sensitivity to fotemustine. Together, we demonstrate that expression of CD271 is responsible for genes associated with DNA repair and drug response. Further, we identified 110 CD271-responsive genes predominantly expressed in melanoma metastases, among them were NEK2, TOP2A and RAD51AP1 as potential drivers of melanoma metastasis. In addition, we provide mechanistic insight in the regulation of CD271 in response to drugs. We found that CD271 is potentially regulated by p53 and in turn is needed for a proper p53-dependent response to DNA-damaging drugs. In summary, we provide for the first time insight in a CD271-associated signaling network connecting CD271 with DNA repair, drug response and metastasis.
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Affiliation(s)
- T Redmer
- German Cancer Consortium (DKTK), German Cancer Research Center (DKFZ), Heidelberg, Germany.,Laboratory of Molecular Tumor Pathology, Institute of Pathology, Charité-Universitätsmedizin Berlin, Berlin, Germany
| | - I Walz
- Laboratory of Molecular Tumor Pathology, Institute of Pathology, Charité-Universitätsmedizin Berlin, Berlin, Germany
| | - B Klinger
- Laboratory of Molecular Tumor Pathology, Institute of Pathology, Charité-Universitätsmedizin Berlin, Berlin, Germany.,Institute for Theoretical Biology, Humboldt-Universität zu Berlin, Berlin, Germany
| | - S Khouja
- Laboratory of Molecular Tumor Pathology, Institute of Pathology, Charité-Universitätsmedizin Berlin, Berlin, Germany
| | - Y Welte
- Laboratory of Molecular Tumor Pathology, Institute of Pathology, Charité-Universitätsmedizin Berlin, Berlin, Germany
| | - R Schäfer
- German Cancer Consortium (DKTK), German Cancer Research Center (DKFZ), Heidelberg, Germany.,Laboratory of Molecular Tumor Pathology, Institute of Pathology, Charité-Universitätsmedizin Berlin, Berlin, Germany
| | - C Regenbrecht
- Laboratory of Molecular Tumor Pathology, Institute of Pathology, Charité-Universitätsmedizin Berlin, Berlin, Germany.,CPO-Cellular Phenomics and Oncology Berlin-Buch GmbH, Berlin, Germany
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22
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Rohr I, Sehouli J, En-Nia A, Heinrich M, Richter R, Chekerov R, Dechend R, Heidecke H, Dragun D, Schäfer R, Gorny X, Lindquist J, Brandt S, Braicu E, Mertens P. Y-box protein-1/p18 as novel serum marker for ovarian cancer diagnosis: A study by the Tumor Bank Ovarian Cancer (TOC). Geburtshilfe Frauenheilkd 2016. [DOI: 10.1055/s-0036-1593015] [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: 10/20/2022] Open
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23
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Kasack K, Schäfer R, Koch H, Küster B. Pan-omic profiling of RAS oncogene-mediated transformation and therapy resistance. Eur J Cancer 2016. [DOI: 10.1016/s0959-8049(16)61620-9] [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: 10/21/2022]
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24
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Beerling E, Seinstra D, de Wit E, Kester L, van der Velden D, Maynard C, Schäfer R, van Diest P, Voest E, van Oudenaarden A, Vrisekoop N, van Rheenen J. Plasticity between Epithelial and Mesenchymal States Unlinks EMT from Metastasis-Enhancing Stem Cell Capacity. Cell Rep 2016; 14:2281-8. [PMID: 26947068 PMCID: PMC4802222 DOI: 10.1016/j.celrep.2016.02.034] [Citation(s) in RCA: 195] [Impact Index Per Article: 24.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2015] [Revised: 12/16/2015] [Accepted: 02/02/2016] [Indexed: 12/20/2022] Open
Abstract
Forced overexpression and/or downregulation of proteins regulating epithelial-to-mesenchymal transition (EMT) has been reported to alter metastasis by changing migration and stem cell capacity of tumor cells. However, these manipulations artificially keep cells in fixed states, while in vivo cells may adapt transient and reversible states. Here, we have tested the existence and role of epithelial-mesenchymal plasticity in metastasis of mammary tumors without artificially modifying EMT regulators. In these tumors, we found by intravital microscopy that the motile tumor cells have undergone EMT, while their epithelial counterparts were not migratory. Moreover, we found that epithelial-mesenchymal plasticity renders any EMT-induced stemness differences, as reported previously, irrelevant for metastatic outgrowth, because mesenchymal cells that arrive at secondary sites convert to the epithelial state within one or two divisions, thereby obtaining the same stem cell potential as their arrived epithelial counterparts. We conclude that epithelial-mesenchymal plasticity supports migration but additionally eliminates stemness-enhanced metastatic outgrowth differences. Direct evidence of EMT obtained in unperturbed breast tumors by real-time visualization EMT exists in breast tumors without experimentally altering EMT inducers Tumor cells that underwent EMT are the migratory cells within a tumor Outgrowth potential differences between states are irrelevant due to plasticity
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Affiliation(s)
- Evelyne Beerling
- Cancer Genomics Center-Hubrecht Institute-KNAW & University Medical Centre Utrecht, Uppsalalaan 8, 3584 CT Utrecht, the Netherlands
| | - Daniëlle Seinstra
- Cancer Genomics Center-Hubrecht Institute-KNAW & University Medical Centre Utrecht, Uppsalalaan 8, 3584 CT Utrecht, the Netherlands
| | - Elzo de Wit
- Cancer Genomics Center-Hubrecht Institute-KNAW & University Medical Centre Utrecht, Uppsalalaan 8, 3584 CT Utrecht, the Netherlands; Netherlands Cancer Institute, Plesmanlaan 121, 1066 CX Amsterdam, the Netherlands
| | - Lennart Kester
- Cancer Genomics Center-Hubrecht Institute-KNAW & University Medical Centre Utrecht, Uppsalalaan 8, 3584 CT Utrecht, the Netherlands
| | | | - Carrie Maynard
- Cancer Genomics Center-Hubrecht Institute-KNAW & University Medical Centre Utrecht, Uppsalalaan 8, 3584 CT Utrecht, the Netherlands
| | - Ronny Schäfer
- Cancer Genomics Center-Hubrecht Institute-KNAW & University Medical Centre Utrecht, Uppsalalaan 8, 3584 CT Utrecht, the Netherlands
| | - Paul van Diest
- Department of Pathology, University Medical Centre Utrecht, Heidelberglaan 100, 3584 CX Utrecht, the Netherlands
| | - Emile Voest
- Netherlands Cancer Institute, Plesmanlaan 121, 1066 CX Amsterdam, the Netherlands
| | - Alexander van Oudenaarden
- Cancer Genomics Center-Hubrecht Institute-KNAW & University Medical Centre Utrecht, Uppsalalaan 8, 3584 CT Utrecht, the Netherlands
| | - Nienke Vrisekoop
- Cancer Genomics Center-Hubrecht Institute-KNAW & University Medical Centre Utrecht, Uppsalalaan 8, 3584 CT Utrecht, the Netherlands.
| | - Jacco van Rheenen
- Cancer Genomics Center-Hubrecht Institute-KNAW & University Medical Centre Utrecht, Uppsalalaan 8, 3584 CT Utrecht, the Netherlands.
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25
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Geisen C, Kann G, Strecker T, Wolf T, Schüttfort G, van Kraaij M, MacLennan S, Rummler S, Weinigel C, Eickmann M, Fehling SK, Krähling V, Seidl C, Seifried E, Schmidt M, Schäfer R. Pathogen-reduced Ebola virus convalescent plasma: first steps towards standardization of manufacturing and quality control including assessment of Ebola-specific neutralizing antibodies. Vox Sang 2016; 110:329-35. [PMID: 26766162 DOI: 10.1111/vox.12376] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2015] [Revised: 12/08/2015] [Accepted: 12/09/2015] [Indexed: 01/16/2023]
Abstract
BACKGROUND Ebola virus disease is a public health emergency of international concern, and enormous efforts are being made in the development of vaccines and therapies. Ebola virus convalescent plasma is a promising anti-infective treatment of Ebola virus disease. Therefore, we developed and implemented a pathogen-reduced Ebola virus convalescent plasma concept in accordance with national, European and global regulatory framework. MATERIALS AND METHODS Ebola virus convalescent plasma manufacture and distribution was managed by a collection centre, two medical centres and an expert group from the European Blood Alliance. Ebola virus convalescent plasma was collected twice with an interval of 61 days from a donor recovering from Ebola virus disease in Germany. After pathogen reduction, the plasma was analysed for Ebola virus-specific immunoglobulin G (IgG) antibodies and its Ebola virus neutralizing activity. RESULTS Convalescent plasma could be collected without adverse events. Anti-Ebola virus IgG titres and Ebola-specific neutralizing antibodies in convalescent plasma were only slightly reduced after pathogen reduction treatment with S59 amotosalen/UVA. A patient in Italy with Ebola virus disease was treated with convalescent plasma without apparent adverse effects. DISCUSSION As proof of principle, we describe a concept and practical implementation of pathogen-reduced Ebola virus convalescent plasma manufacture, quality control and its clinical application to an Ebola virus disease patient.
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Affiliation(s)
- C Geisen
- Institute for Transfusion Medicine and Immunohaematology, German Red Cross Blood Donor Service Baden-Württemberg-Hessen gGmbH, Goethe University Hospital, Frankfurt am Main, Germany
| | - G Kann
- Department of Infectious Diseases, Goethe University Hospital, Frankfurt am Main, Germany
| | - T Strecker
- Institute of Virology, Philipps University Marburg, Marburg, Germany
| | - T Wolf
- Department of Infectious Diseases, Goethe University Hospital, Frankfurt am Main, Germany
| | - G Schüttfort
- Department of Infectious Diseases, Goethe University Hospital, Frankfurt am Main, Germany
| | | | | | - S Rummler
- Institute of Transfusion Medicine, University Hospital Jena, Jena, Germany
| | - C Weinigel
- Institute of Transfusion Medicine, University Hospital Jena, Jena, Germany
| | - M Eickmann
- Institute of Virology, Philipps University Marburg, Marburg, Germany
| | - S K Fehling
- Institute of Virology, Philipps University Marburg, Marburg, Germany
| | - V Krähling
- Institute of Virology, Philipps University Marburg, Marburg, Germany
| | - C Seidl
- Institute for Transfusion Medicine and Immunohaematology, German Red Cross Blood Donor Service Baden-Württemberg-Hessen gGmbH, Goethe University Hospital, Frankfurt am Main, Germany
| | - E Seifried
- Institute for Transfusion Medicine and Immunohaematology, German Red Cross Blood Donor Service Baden-Württemberg-Hessen gGmbH, Goethe University Hospital, Frankfurt am Main, Germany
| | - M Schmidt
- Institute for Transfusion Medicine and Immunohaematology, German Red Cross Blood Donor Service Baden-Württemberg-Hessen gGmbH, Goethe University Hospital, Frankfurt am Main, Germany
| | - R Schäfer
- Institute for Transfusion Medicine and Immunohaematology, German Red Cross Blood Donor Service Baden-Württemberg-Hessen gGmbH, Goethe University Hospital, Frankfurt am Main, Germany
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Shayeghi A, Schäfer R, Rayner DM, Johnston RL, Fielicke A. Charge-induced dipole vs. relativistically enhanced covalent interactions in Ar-tagged Au-Ag tetramers and pentamers. J Chem Phys 2015; 143:024310. [PMID: 26178108 DOI: 10.1063/1.4923255] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Vibrational spectra of Au(n)Ag(m)(+)⋅Ar(k) (n + m = 4, 5; k = 1-4) clusters are determined by far-infrared resonant multiple photon dissociation spectroscopy in the range ν̃=100-250 cm(-1). The experimental spectra are assigned using density functional theory for geometries obtained by the Birmingham cluster genetic algorithm. Putative global minimum candidates of the Ar complexes are generated by adding Ar atoms to the Au(n)Ag(m)(+) low energy isomers and subsequent local optimization. Differential Ar binding energies indicate exceptionally strong Au-Ar bonds in Au-rich clusters, leading to fundamental changes to the IR spectra. The stronger Ar binding is attributed to a relativistically enhanced covalent character of the Au-Ar bond, while in Au-rich species charge-induced dipole interactions overcompensate the relativistic affinity to Au. Moreover, not only the absolute composition but also the topologies are essential in the description of Ar binding to a certain cluster.
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Affiliation(s)
- A Shayeghi
- Eduard-Zintl-Institut, Technische Universität Darmstadt, Alarich-Weiss-Straße 8, 64287 Darmstadt, Germany
| | - R Schäfer
- Eduard-Zintl-Institut, Technische Universität Darmstadt, Alarich-Weiss-Straße 8, 64287 Darmstadt, Germany
| | - D M Rayner
- National Research Council of Canada, 100 Sussex Drive, Ottawa, Ontario K1A 0R6, Canada
| | - R L Johnston
- School of Chemistry, University of Birmingham, Edgbaston, Birmingham B15 2TT, United Kingdom
| | - A Fielicke
- Institut für Optik und Atomare Physik, Technische Universität Berlin, Hardenbergstrasse 36, 10623 Berlin, Germany
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Zomer A, Maynard C, Verweij FJ, Kamermans A, Schäfer R, Beerling E, Schiffelers RM, de Wit E, Berenguer J, Ellenbroek SIJ, Wurdinger T, Pegtel DM, van Rheenen J. In Vivo imaging reveals extracellular vesicle-mediated phenocopying of metastatic behavior. Cell 2015; 161:1046-1057. [PMID: 26000481 PMCID: PMC4448148 DOI: 10.1016/j.cell.2015.04.042] [Citation(s) in RCA: 621] [Impact Index Per Article: 69.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2014] [Revised: 02/06/2015] [Accepted: 04/02/2015] [Indexed: 12/21/2022]
Abstract
Most cancer cells release heterogeneous populations of extracellular vesicles (EVs) containing proteins, lipids, and nucleic acids. In vitro experiments showed that EV uptake can lead to transfer of functional mRNA and altered cellular behavior. However, similar in vivo experiments remain challenging because cells that take up EVs cannot be discriminated from non-EV-receiving cells. Here, we used the Cre-LoxP system to directly identify tumor cells that take up EVs in vivo. We show that EVs released by malignant tumor cells are taken up by less malignant tumor cells located within the same and within distant tumors and that these EVs carry mRNAs involved in migration and metastasis. By intravital imaging, we show that the less malignant tumor cells that take up EVs display enhanced migratory behavior and metastatic capacity. We postulate that tumor cells locally and systemically share molecules carried by EVs in vivo and that this affects cellular behavior.
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Affiliation(s)
- Anoek Zomer
- Cancer Genomics Netherlands, Hubrecht Institute-KNAW & University Medical Center Utrecht, Uppsalalaan 8, 3584 CT Utrecht, the Netherlands
| | - Carrie Maynard
- Cancer Genomics Netherlands, Hubrecht Institute-KNAW & University Medical Center Utrecht, Uppsalalaan 8, 3584 CT Utrecht, the Netherlands
| | - Frederik Johannes Verweij
- Department of Pathology, VU University Medical Center, Cancer Center Amsterdam, De Boelelaan 1117, 1081 HV Amsterdam, the Netherlands
| | - Alwin Kamermans
- Cancer Genomics Netherlands, Hubrecht Institute-KNAW & University Medical Center Utrecht, Uppsalalaan 8, 3584 CT Utrecht, the Netherlands
| | - Ronny Schäfer
- Cancer Genomics Netherlands, Hubrecht Institute-KNAW & University Medical Center Utrecht, Uppsalalaan 8, 3584 CT Utrecht, the Netherlands
| | - Evelyne Beerling
- Cancer Genomics Netherlands, Hubrecht Institute-KNAW & University Medical Center Utrecht, Uppsalalaan 8, 3584 CT Utrecht, the Netherlands
| | - Raymond Michel Schiffelers
- Laboratory Clinical Chemistry & Haematology, University Medical Center Utrecht, Heidelberglaan 100, 3584 CX Utrecht, the Netherlands
| | - Elzo de Wit
- Cancer Genomics Netherlands, Hubrecht Institute-KNAW & University Medical Center Utrecht, Uppsalalaan 8, 3584 CT Utrecht, the Netherlands
| | - Jordi Berenguer
- Department of Neurosurgery, VU University Medical Center, Cancer Center Amsterdam, De Boelelaan 1117, 1081 HV Amsterdam, the Netherlands
| | - Saskia Inge Johanna Ellenbroek
- Cancer Genomics Netherlands, Hubrecht Institute-KNAW & University Medical Center Utrecht, Uppsalalaan 8, 3584 CT Utrecht, the Netherlands
| | - Thomas Wurdinger
- Department of Neurosurgery, VU University Medical Center, Cancer Center Amsterdam, De Boelelaan 1117, 1081 HV Amsterdam, the Netherlands; Department of Neurology, Massachusetts General Hospital and Harvard Medical School, 149 13th Street, Charlestown, MA 02129, USA
| | - Dirk Michiel Pegtel
- Department of Pathology, VU University Medical Center, Cancer Center Amsterdam, De Boelelaan 1117, 1081 HV Amsterdam, the Netherlands
| | - Jacco van Rheenen
- Cancer Genomics Netherlands, Hubrecht Institute-KNAW & University Medical Center Utrecht, Uppsalalaan 8, 3584 CT Utrecht, the Netherlands.
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Korbmacher B, Botzet K, Ulbrich S, Dalyanoglu H, Schipke J, Franz M, Lichtenberg A, Schäfer R. Indication for Perioperative Psychotherapeutic Interventions in Indentified CABG and Mitral Valve Patients. Thorac Cardiovasc Surg 2015. [DOI: 10.1055/s-0035-1544338] [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: 10/24/2022]
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Shayeghi A, Götz D, Davis JBA, Schäfer R, Johnston RL. Pool-BCGA: a parallelised generation-free genetic algorithm for the ab initio global optimisation of nanoalloy clusters. Phys Chem Chem Phys 2014; 17:2104-12. [PMID: 25482360 DOI: 10.1039/c4cp04323e] [Citation(s) in RCA: 75] [Impact Index Per Article: 7.5] [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
The Birmingham cluster genetic algorithm is a package that performs global optimisations for homo- and bimetallic clusters based on either first principles methods or empirical potentials. Here, we present a new parallel implementation of the code which employs a pool strategy in order to eliminate sequential steps and significantly improve performance. The new approach meets all requirements of an evolutionary algorithm and contains the main features of the previous implementation. The performance of the pool genetic algorithm is tested using the Gupta potential for the global optimisation of the Au10Pd10 cluster, which demonstrates the high efficiency of the method. The new implementation is also used for the global optimisation of the Au10 and Au20 clusters directly at the density functional theory level.
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Affiliation(s)
- A Shayeghi
- Eduard-Zintl-Institut, Technische Universität Darmstadt, Alarich-Weiss-Straße 8, 64287 Darmstadt, Germany.
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Shayeghi A, Johnston RL, Schäfer R. Communication: Global minimum search of Ag 10+ with molecular beam optical spectroscopy. J Chem Phys 2014; 141:181104. [DOI: 10.1063/1.4901109] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Affiliation(s)
- A. Shayeghi
- Eduard-Zintl-Institut, Technische Universität Darmstadt, Alarich-Weiss-Straße 8, 64287 Darmstadt, Germany
| | - R. L. Johnston
- School of Chemistry, University of Birmingham, Edgbaston, Birmingham B15 2TT, United Kingdom
| | - R. Schäfer
- Eduard-Zintl-Institut, Technische Universität Darmstadt, Alarich-Weiss-Straße 8, 64287 Darmstadt, Germany
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Abstract
We present experimental and theoretical studies of the optical response of mixed Ag(n)Au(+)(4-n) (n=1-3) clusters in the photon energy range ℏω = 1.9-3.5 eV. Absorption spectra are recorded by a newly built longitudinal molecular beam depletion spectroscopy apparatus providing lower limits to absolute photodissociation cross sections. The experimental data are compared to optical response calculations in the framework of long-range corrected time-dependent density functional theory with initial cluster geometries obtained by the unbiased Birmingham Cluster Genetic Algorithm coupled with density functional theory. Experiments and excited state calculations shed light on the structural and electronic properties of the mixed Ag-Au tetramer cations.
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Affiliation(s)
- A Shayeghi
- Eduard-Zintl-Institut, Technische Universität Darmstadt, Alarich-Weiss-Straße 8, 64287 Darmstadt, Germany
| | - C J Heard
- School of Chemistry, University of Birmingham, Edgbaston, Birmingham B15 2TT, United Kingdom
| | - R L Johnston
- School of Chemistry, University of Birmingham, Edgbaston, Birmingham B15 2TT, United Kingdom
| | - R Schäfer
- Eduard-Zintl-Institut, Technische Universität Darmstadt, Alarich-Weiss-Straße 8, 64287 Darmstadt, Germany
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33
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Mamlouk S, Childs L, Redmer T, Bläker H, Aust D, Schäfer R, Sers C. 685: Linking tumor evolution and therapy response using diagnostic targeted next generation sequencing in colorectal cancer. Eur J Cancer 2014. [DOI: 10.1016/s0959-8049(14)50604-1] [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: 10/25/2022]
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Abstract
The static electric polarizabilities a of silicon clusters with up to 60 atoms have been measured employing a mass selective molecular beam deflection method. The polarizability per atom αN = α/N of the SiN-clusters has been investigated for Si11 and the size ranges N = 14-28, 22-34, 28-44, 34-50, 41 -58, and 42-68. The results show that the polarizability per atom decreases from N = 11 until a minimum at N≥28 is reached. The polarizability per atom increases for N > 28, passes through a maximum at N≈36 and finally converges between N≈50-70 against the value αN =1.9Å3. If the model of a homogeneous dielectric sphere is applied to the larger clusters one calculates that the value αN =1.9Å3 corresponds to a dielectric constant of ε = 3.2. This value is significantly smaller than the dielectric constant of bulk silicon εb = 11.8.
The present paper focuses on the maximum in the polarizability at N≈36. This effect is discussed with special emphasis to recent Car-Parinello calculations which have predicted cage-like silicon structures that enclose a core of several highly coordinated atoms. This structure suggests an improved dielectric sphere model where the core is represented by a smaller sphere with its own dielectric constant εc. It is shown within this model that the observed maximum in polarizability is due to a significant enhancement of the core dielectric constant to a value of εc ≈50. This enhancement is related by means of a simple model to the effect that silicon becomes metallic under high pressure
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Affiliation(s)
- R. Schäfer
- Institut für Physikalische Chemie und Wissenschaftliches Zentrum für Materialwissenschaften, Philipps-Universität Marburg, D-35032 Marburg/Lahn, Germany
| | - J. Woenckhaus
- Institut für Physikalische Chemie und Wissenschaftliches Zentrum für Materialwissenschaften, Philipps-Universität Marburg, D-35032 Marburg/Lahn, Germany
| | - J. A. Becker
- Institut für Physikalische Chemie und Wissenschaftliches Zentrum für Materialwissenschaften, Philipps-Universität Marburg, D-35032 Marburg/Lahn, Germany
| | - F. Hensel
- Institut für Physikalische Chemie und Wissenschaftliches Zentrum für Materialwissenschaften, Philipps-Universität Marburg, D-35032 Marburg/Lahn, Germany
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Wirth R, Smoliner C, Spamer C, Marburger C, Schreiber FS, Willschrei HP, Lenzen-Großimlinghaus R, Schäfer R, Volkert D. Do doctors know how much nutrition patients need—a survey from Germany? Eur J Clin Nutr 2014; 68:840-3. [DOI: 10.1038/ejcn.2014.94] [Citation(s) in RCA: 8] [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] [Received: 02/11/2014] [Revised: 03/21/2014] [Accepted: 04/10/2014] [Indexed: 11/09/2022]
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36
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Götz DA, Shayeghi A, Johnston RL, Schwerdtfeger P, Schäfer R. Influence of spin-orbit effects on structures and dielectric properties of neutral lead clusters. J Chem Phys 2014; 140:164313. [DOI: 10.1063/1.4872369] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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37
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Fisc W, Bergf R, Pla C, Schäfer R, Schopfer P. Accumulation of Storage Materials, Precocious Germination and Development of Desiccation Tolerance During Seed Maturation in Mustard (Sinapis albaL.). ACTA ACUST UNITED AC 2014. [DOI: 10.1111/j.1438-8677.1988.tb00055.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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38
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Popescu R, Schäfer R, Califano R, Eckert R, Coleman R, Douillard JY, Cervantes A, Casali P, Sessa C, Van Cutsem E, de Vries E, Pavlidis N, Fumasoli K, Wörmann B, Samonigg H, Cascinu S, Cruz Hernández J, Howard A, Ciardiello F, Stahel R, Piccart M. The current and future role of the medical oncologist in the professional care for cancer patients: a position paper by the European Society for Medical Oncology (ESMO). Ann Oncol 2014; 25:9-15. [DOI: 10.1093/annonc/mdt522] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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39
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Malek A, Gyorffy B, Catapano CV, Schäfer R. Selection of optimal combinations of target genes for therapeutic multi-gene silencing based on miRNA co-regulation. Cancer Gene Ther 2013; 20:326-9. [DOI: 10.1038/cgt.2013.20] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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40
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Franz M, Weihrauch L, Schäfer R. PALME – Ankunft in der Wirklichkeit. Gesundheitswesen 2013; 77 Suppl 1:S131-2. [DOI: 10.1055/s-0032-1330026] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Affiliation(s)
- M. Franz
- Klinisches Institut für Psychosomatische Medizin und Psychotherapie, Universitätsklinikum Düsseldorf
| | - L. Weihrauch
- Klinisches Institut für Psychosomatische Medizin und Psychotherapie, Universitätsklinikum Düsseldorf
| | - R. Schäfer
- Klinisches Institut für Psychosomatische Medizin und Psychotherapie, Universitätsklinikum Düsseldorf
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41
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Ulbrich S, Dalyanoglu H, Lichtenberg A, Schipke J, Franz M, Schäfer R, Korbmacher B. Perioperative and Long-Term Development of Anxiety and Depression in CABG Patients. Thorac Cardiovasc Surg 2013; 61:676-81. [DOI: 10.1055/s-0032-1333326] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Affiliation(s)
- S. Ulbrich
- Clinic for Cardiovascular Surgery, University Hospital Düsseldorf, Düsseldorf, Germany
| | - H. Dalyanoglu
- Clinic for Cardiovascular Surgery, University Hospital Düsseldorf, Düsseldorf, Germany
| | - A. Lichtenberg
- Clinic for Cardiovascular Surgery, University Hospital Düsseldorf, Düsseldorf, Germany
| | - J. Schipke
- Research Group Experimental Surgery, Clinic for Cardiovascular Surgery, University Hospital Düsseldorf, Düsseldorf, Germany
| | - M. Franz
- Clinical Institute of Psychosomatic Medicine and Psychotherapy, University Hospital Düsseldorf, Düsseldorf, Germany
| | - R. Schäfer
- Clinical Institute of Psychosomatic Medicine and Psychotherapy, University Hospital Düsseldorf, Düsseldorf, Germany
| | - B. Korbmacher
- Clinic for Cardiovascular Surgery, University Hospital Düsseldorf, Düsseldorf, Germany
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Korbmacher B, Botzet K, Dalyanoglu H, Schipke JD, Franz M, Lichtenberg A, Schäfer R. Anxiety and depression in mitral valve patients: Perioperatively and 6 months after surgery. Thorac Cardiovasc Surg 2013. [DOI: 10.1055/s-0032-1332557] [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: 10/27/2022]
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43
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Shayeghi A, Johnston RL, Schäfer R. Evaluation of photodissociation spectroscopy as a structure elucidation tool for isolated clusters: a case study of Ag4+ and Au4+. Phys Chem Chem Phys 2013; 15:19715-23. [DOI: 10.1039/c3cp52160e] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
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44
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Prochnow D, Höing B, Kleiser R, Lindenberg R, Wittsack HJ, Schäfer R, Franz M, Seitz R. The neural correlates of affect reading: An fMRI study on faces and gestures. Behav Brain Res 2013; 237:270-7. [DOI: 10.1016/j.bbr.2012.08.050] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2012] [Revised: 08/22/2012] [Accepted: 08/29/2012] [Indexed: 12/30/2022]
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45
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Franz M, Weihrauch LIV, Schäfer R, Straß C. PALME: Ein bindungsorientiertes Elterntraining für alleinerziehende Mütter – Langzeiteffekte und Weiterentwicklung. Dtsch Med Wochenschr 2012. [DOI: 10.1055/s-0032-1323240] [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: 10/27/2022]
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46
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Iden S, van Riel WE, Schäfer R, Song JY, Hirose T, Ohno S, Collard JG. Tumor type-dependent function of the par3 polarity protein in skin tumorigenesis. Cancer Cell 2012; 22:389-403. [PMID: 22975380 DOI: 10.1016/j.ccr.2012.08.004] [Citation(s) in RCA: 96] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/26/2011] [Revised: 01/31/2012] [Accepted: 08/06/2012] [Indexed: 12/20/2022]
Abstract
Cell polarization is crucial during development and tissue homeostasis and is regulated by conserved proteins of the Scribble, Crumbs, and Par complexes. In mouse skin tumorigenesis, Par3 deficiency results in reduced papilloma formation and growth. Par3 mediates its tumor-promoting activity through regulation of growth and survival, since Par3 deletion increases apoptosis and reduces growth in vivo and in vitro. In contrast, Par3-deficient mice are predisposed to formation of keratoacanthomas, cutaneous tumors thought to originate from different cellular origin and frequently observed in humans. Par3 expression is reduced in both mouse and human keratoacanthomas, indicating tumor-suppressive properties of Par3. Our results identify a dual function of Par3 in skin cancer, with both pro-oncogenic and tumor-suppressive activity depending on the tumor type.
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Affiliation(s)
- Sandra Iden
- Division of Cell Biology I, The Netherlands Cancer Institute, 1066 CX Amsterdam, The Netherlands.
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47
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Becker J, Kind S, Buschke N, Schiefelbein S, Schäfer R, Wittmann C. Systems Metabolic Engineering von Corynebacterium glutamicum für die industrielle Bioproduktion. CHEM-ING-TECH 2012. [DOI: 10.1002/cite.201250138] [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: 11/07/2022]
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48
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Schäfer R, Buschke N, Becker J, Wittmann C. Systembiotechnologie von Corynebacterium glutamicum Nachhaltige Produktion von Lysin aus Hemicellulose. CHEM-ING-TECH 2012. [DOI: 10.1002/cite.201250137] [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: 11/06/2022]
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49
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Medina Perez P, Schäfer R. 350 Leukemogenic and Noonan Syndrome-related SHP-2 Mutations Promote Oncogenic Transformation. Eur J Cancer 2012. [DOI: 10.1016/s0959-8049(12)71040-7] [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: 10/28/2022]
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50
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Zomer A, Kamermans A, Schäfer R, Ritsma L, Beerling E, de Graaff A, Ellenbroek S, Vrisekoop N, van Rheenen J. 154 In Vivo Tracing of Tumor-initiating Cells in Transgenic Mice. Eur J Cancer 2012. [DOI: 10.1016/s0959-8049(12)70854-7] [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: 11/25/2022]
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