1,324 results on '"Markus, C."'
Search Results
2. Conformation-dependent ligand hot spots in the spliceosomal RNA helicase BRR2
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Karen Vester, Alexander Metz, Simon Huber, Bernhard Loll, and Markus C. Wahl
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binding modes ,conformation ,RNA helicase BRR2 ,Structural Biology ,fragment screening ,ligand hot spots ,500 Naturwissenschaften und Mathematik::540 Chemie::540 Chemie und zugeordnete Wissenschaften ,drug discovery - Abstract
The conversion of hits to leads in drug discovery involves the elaboration of chemical core structures to increase their potency. In fragment-based drug discovery, low-molecular-weight compounds are tested for protein binding and are subsequently modified, with the tacit assumption that the binding mode of the original hit will be conserved among the derivatives. However, deviations from binding mode conservation are rather frequently observed, but potential causes of these alterations remain incompletely understood. Here, two crystal forms of the spliceosomal RNA helicase BRR2 were employed as a test case to explore the consequences of conformational changes in the target protein on the binding behaviour of fragment derivatives. The initial fragment, sulfaguanidine, bound at the interface between the two helicase cassettes of BRR2 in one crystal form. Second-generation compounds devised by structure-guided docking were probed for their binding to BRR2 in a second crystal form, in which the original fragment-binding site was altered due to a conformational change. While some of the second-generation compounds retained binding to parts of the original site, others changed to different binding pockets of the protein. A structural bioinformatics analysis revealed that the fragment-binding sites correspond to predicted binding hot spots, which strongly depend on the protein conformation. This case study offers an example of extensive binding-mode changes during hit derivatization, which are likely to occur as a consequence of multiple binding hot spots, some of which are sensitive to the flexibility of the protein.
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- 2023
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3. Exo‐ and endophytic fungi enable rapid transfer of nutrients from ant waste to orchid tissue
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Christian Gegenbauer, Anke Bellaire, Arno Schintlmeister, Markus C. Schmid, Markus Kubicek, Hermann Voglmayr, Gerhard Zotz, Andreas Richter, and Veronika E. Mayer
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Physiology ,Plant Science - Published
- 2023
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4. N,N′-Substituted quinacridones for organic electronic device applications
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Donia Saadi, Felix Mayr, Cigdem Yumusak, Dominik Wielend, Munise Cobet, Bilge Kahraman, Cristian Vlad Irimia, Yasin Kanbur, Mateusz Bednorz, Kamil Kotwica, Amel Ben Fredj, Samir Romdhane, Markus C. Scharber, Niyazi Serdar Sariciftci, and Mihai Irimia-Vladu
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Chemistry (miscellaneous) ,General Materials Science - Abstract
N,N′-Substituted quinacridones are a novel class of commercially available quinacridones for organic electronics which are reported here.
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- 2023
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5. Large-Scale Crystallographic Fragment Screening Expedites Compound Optimization and Identifies Putative Protein–Protein Interaction Sites
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Tatjana Barthel, Jan Wollenhaupt, Gustavo M. A. Lima, Markus C. Wahl, and Manfred S. Weiss
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Binding Sites ,Drug Discovery ,Proteins ,Molecular Medicine ,Crystallography, X-Ray ,Ligands ,Protein Binding - Abstract
The identification of starting points for compound development is one of the key steps in early-stage drug discovery. Information-rich techniques such as crystallographic fragment screening can potentially increase the efficiency of this step by providing the structural information of the binding mode of the ligands in addition to the mere binding information. Here, we present the crystallographic screening of our 1000-plus-compound F2X-Universal Library against the complex of the yeast spliceosomal Prp8 RNaseH-like domain and the snRNP assembly factor Aar2. The observed 269 hits are distributed over 10 distinct binding sites on the surface of the protein-protein complex. Our work shows that hit clusters from large-scale crystallographic fragment screening campaigns identify known interaction sites with other proteins and suggest putative additional interaction sites. Furthermore, the inherent binding pose validation within the hit clusters may accelerate downstream compound optimization.
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- 2022
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6. Two Cases of Monkeypox-Associated Encephalomyelitis — Colorado and the District of Columbia, July–August 2022
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Daniel M. Pastula, Matthew J. Copeland, Markus C. Hannan, Samuel Rapaka, Takashi Kitani, Elizabeth Kleiner, Adrienne Showler, Cindy Yuen, Elizabeth M. Ferriman, Jennifer House, Shannon O’Brien, Alexis Burakoff, Bhavik Gupta, Kelli M. Money, Elizabeth Matthews, J. David Beckham, Lakshmi Chauhan, Amanda L. Piquet, Rebecca N. Kumar, Carlo S. Tornatore, Kia Padgett, Kevin O’Laughlin, Anil T. Mangla, Princy N. Kumar, Kenneth L. Tyler, and Siobhán M. O’Connor
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Male ,Colorado ,Health (social science) ,Epidemiology ,Health, Toxicology and Mutagenesis ,Monkeypox ,General Medicine ,Exanthema ,United States ,Sexual and Gender Minorities ,Health Information Management ,District of Columbia ,Humans ,Homosexuality, Male ,Monkeypox virus ,Encephalomyelitis - Abstract
Monkeypox virus (MPXV) is an orthopoxvirus in the Poxviridae family. The current multinational monkeypox outbreak has now spread to 96 countries that have not historically reported monkeypox, with most cases occurring among gay, bisexual, and other men who have sex with men (1,2). The first monkeypox case in the United States associated with this outbreak was identified in May 2022 in Massachusetts (1); monkeypox has now been reported in all 50 states, the District of Columbia (DC), and one U.S. territory. MPXV is transmitted by close contact with infected persons or animals; infection results in a febrile illness followed by a diffuse vesiculopustular rash and lymphadenopathy. However, illness in the MPXV current Clade II outbreak has differed: the febrile prodrome is frequently absent or mild, and the rash often involves genital, anal, or oral regions (3,4). Although neuroinvasive disease has been previously reported with MPXV infection (5,6), it appears to be rare. This report describes two cases of encephalomyelitis in patients with monkeypox disease that occurred during the current U.S. outbreak. Although neurologic complications of acute MPXV infections are rare, suspected cases should be reported to state, tribal, local, or territorial health departments to improve understanding of the range of clinical manifestations of and treatment options for MPXV infections during the current outbreak.
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- 2022
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7. Negative association between fatigue and signs of sleep apnoea in patients after COVID-19
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Markus C. Hayden, Gabriele Schwarzl, Matthias Limbach, Sorin Mitrea, Michael Schuler, Dennis Nowak, and Konrad Schultz
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Pulmonary and Respiratory Medicine - Published
- 2022
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8. Vorwort
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Blaich, Markus C.
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Nachrichten aus Niedersachsens Urgeschichte, Bd. 88 (2019): Nachrichten aus Niedersachsens Urgeschichte
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- 2023
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9. Prof. Dr.-Ing. Karl Bernhard Kruse (1952 – 2020)
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Blaich, Markus C.
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Nachrichten aus Niedersachsens Urgeschichte, Bd. 89 (2020): Nachrichten aus Niedersachsens Urgeschichte
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- 2023
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10. Vorwort
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Blaich, Markus C.
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Nachrichten aus Niedersachsens Urgeschichte, Bd. 89 (2020): Nachrichten aus Niedersachsens Urgeschichte
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- 2023
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11. Pfalz Königsdahlum – wieder gefunden und doch entschwunden?
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Blaich, Markus C.
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Nachrichten aus Niedersachsens Urgeschichte, Bd. 89 (2020): Nachrichten aus Niedersachsens Urgeschichte
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- 2023
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12. Walter Hauser, Martin Mittermair (Hrsg.) Schloss Tirol
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Blaich, Markus C.
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Rezension zu: Walter Hauser, Martin Mittermair (Hrsg.) Schloss Tirol – Band 1 Baugeschichte: Die Burg Tirol von ihren Anfängen bis zum 21. Jahrhundert. Mit Beiträgen von I. Heitmeier, J. Goll, H. Nothdurfter, H. Stadler, E. Flatscher, W. Landi, M. Mittermair, W. Hauser, C. Meckseper, G. Faccani, L. Andergassen, C. Wolfgang, E. Crettaz-Stürzel, K. Nicolussi, P. Mirwald und A. Recheis. Athesia Verlag, Bozen, 2017. 575 Seiten mit zahlreichen, meist farbigen Abbildungen, dazu Planmappe und DVD. ISBN 978 – 88-95523 – 25-5 Martin Mittermair (Hrsg.) Schloss Tirol – Band 2 Raumbuch: Die bauhistorischen und archäologischen Befunde. Mit Beiträgen von E. Flatscher, M. Schick und F. Messner. Athesia Verlag, Bozen, 2017. 511 Seiten mit zahlreichen, meist farbigen Abbildungen. ISBN 978 – 88-95523 – 24-8 Harald Stadler, Elias Flatscher (Hrsg.) Schloss Tirol – Band 3 Archäologie: Die archäologischen Befunde und Funde. Mit Beiträgen von A. Awad-Konrad, F. Brenker, C. Bürger, B. Denicoló, E. Flatscher, D. Jaumann, S. Leib, F. Messner, B. Nutz, M. Schick, A. Torggler und D. Zanetti. Athesia Verlag, Bozen, 2018. 454 Seiten mit zahlreichen, meist farbigen Abbildungen. ISBN 978 – 88-95523 – 18-7, Nachrichten aus Niedersachsens Urgeschichte, Bd. 89 (2020): Nachrichten aus Niedersachsens Urgeschichte
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- 2023
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13. Rolf Bärenfänger und Jan F. Kegler (Hrsg.), Ihlow II. Archäologische und anthropologische Forschungen zu einem ehemaligen Zisterzienserkloster in Ostfriesland
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Blaich, Markus C.
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Rezension zu: Rolf Bärenfänger und Jan F. Kegler (Hrsg.), Ihlow II. Archäologische und anthropologische Forschungen zu einem ehemaligen Zisterzienserkloster in Ostfriesland mit Beiträgen von Bernhard Thiemann und Melanie Timmermann Beiträge zur Archäologie in Niedersachsen, Band 21 Verlag Marie Leidorf, Rahden / Westf., 2020 412 Seiten, 249 Abbildungen, Tabellen und Tafeln. ISBN 978 – 3-89646 – 941-0, Nachrichten aus Niedersachsens Urgeschichte, Bd. 89 (2020): Nachrichten aus Niedersachsens Urgeschichte
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- 2023
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14. Volker Hemmerich, Kloster Lüne. Die mittelalterliche Baugeschichte
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Blaich, Markus C.
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Rezension zu: Volker Hemmerich Kloster Lüne. Die mittelalterliche Baugeschichte Petersberg, Michael Imhof Verlag, 2018 176 Seiten, 234 Abbildungen ISBN 978-3-7319-0786-2, Nachrichten aus Niedersachsens Urgeschichte, Bd. 88 (2019): Nachrichten aus Niedersachsens Urgeschichte
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- 2023
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15. Stefan Albrecht (Hrsg.): Großmähren und seine Nachbarn
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Blaich, Markus C.
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Rezension zu: Stefan Albrecht (Hrsg.): Großmähren und seine Nachbarn (Forschungen zu Geschichte und Kultur der Böhmischen Länder 5). Berlin/Bern/Wien: Peter Lang 2021. 314 Seiten, 25 Abbildungen, ISBN 978-3-63184-571-4 (Hardcover)/ 978-3-63185-362-7 (Download PDF), Mitteilungen der Deutschen Gesellschaft für Archäologie des Mittelalters und der Neuzeit, Bd. 35 (2022): Mitteilungen der DGAMN: Tiere in Stadt und Land (und Kloster)
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- 2023
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16. Supplementary Figure 1 from Targeted and Nontargeted Effects of Ionizing Radiation That Impact Genomic Instability
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Mary Helen Barcellos-Hoff, Bahram Parvin, Shraddha A. Ravani, Rishi Gupta, Arnaud Boissière, Anna C. Erickson, Sylvain V. Costes, Markus C. Fleisch, and Christopher A. Maxwell
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Supplementary Figure 1 from Targeted and Nontargeted Effects of Ionizing Radiation That Impact Genomic Instability
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- 2023
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17. Retrospective cohort study to devise a treatment decision score predicting adverse 24-month radiological activity in early multiple sclerosis
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Alexander Hapfelmeier, Begum Irmak On, Mark Mühlau, Jan S. Kirschke, Achim Berthele, Christiane Gasperi, Ulrich Mansmann, Alexander Wuschek, Matthias Bussas, Martin Boeker, Antonios Bayas, Makbule Senel, Joachim Havla, Markus C. Kowarik, Klaus Kuhn, Ingrid Gatz, Helmut Spengler, Benedikt Wiestler, Lioba Grundl, Dominik Sepp, and Bernhard Hemmer
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Pharmacology ,Neurology ,Original Research ,machine learning ,multiple sclerosis ,personalized medicine ,predictive factor ,predictive model ,treatment effect ,Neurology (clinical) ,ddc:610 ,ddc - Abstract
Background: Multiple sclerosis (MS) is a chronic neuroinflammatory disease affecting about 2.8 million people worldwide. Disease course after the most common diagnoses of relapsing-remitting multiple sclerosis (RRMS) and clinically isolated syndrome (CIS) is highly variable and cannot be reliably predicted. This impairs early personalized treatment decisions. Objectives: The main objective of this study was to algorithmically support clinical decision-making regarding the options of early platform medication or no immediate treatment of patients with early RRMS and CIS. Design: Retrospective monocentric cohort study within the Data Integration for Future Medicine (DIFUTURE) Consortium. Methods: Multiple data sources of routine clinical, imaging and laboratory data derived from a large and deeply characterized cohort of patients with MS were integrated to conduct a retrospective study to create and internally validate a treatment decision score [Multiple Sclerosis Treatment Decision Score (MS-TDS)] through model-based random forests (RFs). The MS-TDS predicts the probability of no new or enlarging lesions in cerebral magnetic resonance images (cMRIs) between 6 and 24 months after the first cMRI. Results: Data from 65 predictors collected for 475 patients between 2008 and 2017 were included. No medication and platform medication were administered to 277 (58.3%) and 198 (41.7%) patients. The MS-TDS predicted individual outcomes with a cross-validated area under the receiver operating characteristics curve (AUROC) of 0.624. The respective RF prediction model provides patient-specific MS-TDS and probabilities of treatment success. The latter may increase by 5–20% for half of the patients if the treatment considered superior by the MS-TDS is used. Conclusion: Routine clinical data from multiple sources can be successfully integrated to build prediction models to support treatment decision-making. In this study, the resulting MS-TDS estimates individualized treatment success probabilities that can identify patients who benefit from early platform medication. External validation of the MS-TDS is required, and a prospective study is currently being conducted. In addition, the clinical relevance of the MS-TDS needs to be established.
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- 2023
18. Branch point strength controls species-specific CAMK2B alternative splicing and regulates LTP
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Andreas Franz, A Ioana Weber, Marco Preußner, Nicole Dimos, Alexander Stumpf, Yanlong Ji, Laura Moreno-Velasquez, Anne Voigt, Frederic Schulz, Alexander Neumann, Benno Kuropka, Ralf Kühn, Henning Urlaub, Dietmar Schmitz, Markus C Wahl, and Florian Heyd
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Cancer Research ,Ecology ,Health, Toxicology and Mutagenesis ,species-specific CAMK2B ,500 Naturwissenschaften und Mathematik::570 Biowissenschaften ,Biologie::570 Biowissenschaften ,Biologie ,Plant Science ,Technology Platforms ,Function and Dysfunction of the Nervous System ,Biochemistry, Genetics and Molecular Biology (miscellaneous) - Abstract
Regulation and functionality of species-specific alternative splicing has remained enigmatic to the present date. Calcium/calmodulin-dependent protein kinase IIβ (CaMKIIβ) is expressed in several splice variants and plays a key role in learning and memory. Here, we identify and characterize several primate-specificCAMK2Bsplice isoforms, which show altered kinetic properties and changes in substrate specificity. Furthermore, we demonstrate that primate-specificCAMK2Balternative splicing is achieved through branch point weakening during evolution. We show that reducing branch point and splice site strengths during evolution globally renders constitutive exons alternative, thus providing novel mechanistic insight intocis-directed species-specific alternative splicing regulation. Using CRISPR/Cas9, we introduce a weaker, human branch point sequence into the mouse genome, resulting in strongly alteredCamk2bsplicing in the brains of mutant mice. We observe a strong impairment of long-term potentiation in CA3-CA1 synapses of mutant mice, thus connecting branch point–controlledCAMK2Balternative splicing with a fundamental function in learning and memory.
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- 2023
19. Cystic fibrosis transmembrane conductance regulator modulators attenuate platelet activation and aggregation in blood of healthy donors and COVID-19 patients
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Erik Asmus, Weronika Karle, Markus C. Brack, Corey Wittig, Felix Behrens, Leander Reinshagen, Moritz Pfeiffer, Sabrina Schulz, Bertina Mandzimba-Maloko, Lasti Erfinanda, Paul L. Perret, Laura Michalick, Patrick J. Smeele, Endry H.T. Lim, Charissa E. van den Brom, Alexander B.A. Vonk, Toralf Kaiser, Norbert Suttorp, Stefan Hippenstiel, Leif E. Sander, Florian Kurth, Ursula Rauch, Ulf Landmesser, Arash Haghikia, Robert Preissner, Harm J. Bogaard, Martin Witzenrath, Wolfgang M. Kuebler, Robert Szulcek, Szandor Simmons, Graduate School, Intensive Care Medicine, AII - Amsterdam institute for Infection and Immunity, ANS - Amsterdam Neuroscience, Pulmonary medicine, ACS - Microcirculation, Anesthesiology, Intensive care medicine, Cardio-thoracic surgery, ACS - Atherosclerosis & ischemic syndromes, ACS - Heart failure & arrhythmias, and ACS - Pulmonary hypertension & thrombosis
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Pulmonary and Respiratory Medicine ,Cystic Fibrosis ,Health Status ,Mutation ,COVID-19 ,Cystic Fibrosis Transmembrane Conductance Regulator/genetics ,Humans ,Platelet Activation - Abstract
Cystic fibrosis transmembrane conductance regulator (CFTR) modulators reduce agonist-induced platelet activation and function. CFTR modulators, such as ivacaftor, present a promising therapeutic strategy in thrombocytopathies, including severe COVID-19. https://bit.ly/3HJykdt
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- 2023
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20. A non‐native C‐terminal extension of the β’ subunit compromises <scp>RNA</scp> polymerase and Rho functions
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Maura Mittermeier, Bing Wang, Nelly Said, Daniela Gjorgjevikj, Markus C. Wahl, and Irina Artsimovitch
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Transcription, Genetic ,Escherichia coli Proteins ,Operon ,Escherichia coli ,Trans-Activators ,DNA-Directed RNA Polymerases ,Transcriptional Elongation Factors ,Peptide Elongation Factors ,Molecular Biology ,Microbiology ,Article ,Transcription Factors - Abstract
Escherichia coli RfaH abrogates Rho-mediated polarity in lipopolysaccharide core biosynthesis operons, and ΔrfaH cells are hypersensitive to antibiotics, bile salts, and detergents. Selection for rfaH suppressors that restore growth on SDS identified a temperature-sensitive mutant in which 46 C-terminal residues of the RNA polymerase (RNAP) β’ subunit are replaced with 23 residues carrying a net positive charge. Based on similarity to rpoC397, which confers a temperature-sensitive phenotype and resistance to bacteriophages, we named this mutant rpoC397*. We show that SDS resistance depends on a single nonpolar residue within the C397* tail, whereas basic residues are dispensable. In line with its mimicry of RfaH, C397* RNAP is resistant to Rho but responds to pause signals, NusA, and NusG in vitro similarly to the wild-type enzyme and binds to Rho and Nus factors in vivo. Strikingly, the deletion of rpoZ, which encodes the ω “chaperone” subunit, restores rpoC397* growth at 42 °C but has no effect on SDS sensitivity. Our results suggest that the C397* tail traps the ω subunit in an inhibitory state through direct contacts and hinders Rho-dependent termination through long-range interactions. We propose that the dynamic and hypervariable β’•ω module controls RNA synthesis in response to niche-specific signals.
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- 2022
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21. CryoEM analysis of small plant biocatalysts at sub-2 Å resolution
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Nicole Dimos, Carl P. O. Helmer, Andrea M. Chánique, Markus C. Wahl, Robert Kourist, Tarek Hilal, and Bernhard Loll
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Models, Molecular ,Molecular Structure ,high resolution ,green chemistry ,cryo electron microscopy ,camphor ,terpenes ,borneol dehydrogenases ,plant biocatalysts ,Cryoelectron Microscopy ,fungi ,food and beverages ,cryo-electron microscopy ,Plants ,Protein Engineering ,Research Papers ,Catalysis ,Enzymes ,Alcohol Oxidoreductases ,Structural Biology ,Salvia ,Salvia officinalis ,500 Naturwissenschaften und Mathematik::540 Chemie::540 Chemie und zugeordnete Wissenschaften - Abstract
Although cryo-electron microscopy has revolutionized structural biology, its applicability to high-resolution structural analysis of comparatively small enzymes so far remains largely unexplored. Here, two cryo-EM structures of plant borneol dehydrogenases of ∼120 kDa at or below 2 Å resolution are reported., Enzyme catalysis has emerged as a key technology for developing efficient, sustainable processes in the chemical, biotechnological and pharmaceutical industries. Plants provide large and diverse pools of biosynthetic enzymes that facilitate complex reactions, such as the formation of intricate terpene carbon skeletons, with exquisite specificity. High-resolution structural analysis of these enzymes is crucial in order to understand their mechanisms and modulate their properties by targeted engineering. Although cryo-electron microscopy (cryoEM) has revolutionized structural biology, its applicability to high-resolution structural analysis of comparatively small enzymes has so far been largely unexplored. Here, it is shown that cryoEM can reveal the structures of plant borneol dehydrogenases of ∼120 kDa at or below 2 Å resolution, paving the way for the rapid development of new biocatalysts that can provide access to bioactive terpenes and terpenoids.
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- 2022
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22. Wide-bandgap organic solar cells with a novel perylene-based non-fullerene acceptor enabling open-circuit voltages beyond 1.4 V
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Jakob Hofinger, Stefan Weber, Felix Mayr, Anna Jodlbauer, Matiss Reinfelds, Thomas Rath, Gregor Trimmel, and Markus C. Scharber
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Renewable Energy, Sustainability and the Environment ,General Materials Science ,General Chemistry - Abstract
A novel wide-bandgap perylene-based acceptor (PMI-FF-PMI) allows the fabrication of efficient organic solar cells with an extraordinary high open-circuit voltage beyond 1.4 V.
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- 2022
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23. Ion-driven nanograin formation in early-stage degradation of tri-cation perovskite films
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Filipe Richheimer, David Toth, Bekele Hailegnaw, Mark A. Baker, Robert A. Dorey, Ferry Kienberger, Fernando A. Castro, Martin Kaltenbrunner, Markus C. Scharber, Georg Gramse, and Sebastian Wood
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General Materials Science - Abstract
The operational stability of organic-inorganic halide perovskite based solar cells is a challenge for widespread commercial adoption. The mobility of ionic species is a key contributor to perovskite instability since ion migration can lead to unfavourable changes in the crystal lattice and ultimately destabilisation of the perovskite phase. Here we study the nanoscale early-stage degradation of mixed-halide mixed-cation perovskite films under operation-like conditions using electrical scanning probe microscopy to investigate the formation of surface nanograin defects. We identify the nanograins as lead iodide and study their formation in ambient and inert environments with various optical, thermal, and electrical stress conditions in order to elucidate the different underlying degradation mechanisms. We find that the intrinsic instability is related to the polycrystalline morphology, where electrical bias stress leads to the build-up of charge at grain boundaries and lateral space charge gradients that destabilise the local perovskite lattice facilitating escape of the organic cation. This mechanism is accelerated by enhanced ionic mobility under optical excitation. Our findings highlight the importance of inhibiting the formation of local charge imbalance, either through compositions preventing ionic redistribution or local grain boundary passivation, in order to extend operational stability in perovskite photovoltaics.
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- 2022
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24. Overcoming intra-molecular repulsions in PEDTT by sulphate counter-ion
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T. Greunz, Niyazi Serdar Sariciftci, Achim Walter Hassel, Dominik Farka, Christoph Cobet, Cezarina Cela Mardare, Markus C. Scharber, Cigdem Yumusak, and David Stifter
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chemistry.chemical_classification ,pedtt ,Materials science ,Inorganic chemistry ,Focus on Optical, magnetic and electronic device materials ,106 Metallic materials ,pedot ,201 Electronics / Semiconductor / TCOs ,301 Chemical syntheses / processing ,chemistry ,metal–insulator transition ,TA401-492 ,General Materials Science ,105 Low-Dimension (1D/2D) materials ,Counterion ,203 Magnetics / Spintronics / Superconductors ,conducting polymers ,magnetotransport ,Materials of engineering and construction. Mechanics of materials ,500 Characterization ,TP248.13-248.65 ,Research Article ,Biotechnology - Abstract
We set out to demonstrate the development of a highly conductive polymer based on poly-(3,4-ethylenedithia thiophene) (PEDTT), PEDOTs structural analogue historically notorious for structural disorder and limited conductivities. The caveat therein was previously described to lie in intra-molecular repulsions. We demonstrate how a tremendous >2600-fold improvement in conductivity and metallic features, such as magnetoconductivity can be achieved. This is achieved through a careful choice of the counter-ion (sulphate) and the use of oxidative chemical vapour deposition (oCVD). It is shown that high structural order on the molecular level was established and the formation of crystallites tens of nanometres in size was achieved. We infer that the sulphate ions therein intercalate between the polymer chains, thus forming densely packed crystals of planar molecules with extended π-systems. Consequently, room-temperature conductivities of above 1000 S cm−1 are achieved, challenging those of conventional PEDOT:PSS. The material is in the critical regime of the metal–insulator transition., GRAPHICAL ABSTRACTS
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- 2021
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25. Clinical-Radiological Mismatch in Multiple Sclerosis Patients during Acute Relapse: Discrepancy between Clinical Symptoms and Active, Topographically Fitting MRI Lesions
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Jutta Dünschede, Christoph Ruschil, Benjamin Bender, Annerose Mengel, Tobias Lindig, Ulf Ziemann, and Markus C. Kowarik
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multiple sclerosis ,disease activity ,relapse ,magnetic resonance imaging (MRI) ,clinical-radiological mismatch ,General Medicine - Abstract
Background: Relapses in multiple sclerosis (MS) patients are usually defined as subacute clinical symptoms that last for at least 24 h. To validate a clinical relapse on magnetic resonance imaging (MRI), an anatomically fitting lesion with gadolinium enhancement in the central nervous system (CNS) would be mandatory. The aim of this study was to validate clinical relapses in regard to the concomitant detection of active, anatomically fitting MRI lesions. Methods: We performed a retrospective analysis of 199 MS patients with acute relapse who had received an MRI scan before the initiation of methylprednisolone (MPS) therapy. Clinical data and MRIs were systematically reanalyzed by correlating clinical symptoms with their anatomical representation in the CNS. Patients were then categorized into subgroups with a clinical-radiological match (group 1) or clinical-radiological mismatch (group 2) between symptoms and active, topographically fitting lesions and further analyzed in regard to clinical characteristics. Results: In 43% of our patients, we observed a clinical-radiological mismatch (group 2). Further analysis of patient characteristics showed that these patients were significantly older at the time of relapse. MS patients in group 2 also showed a significantly longer disease duration and significantly more previous relapses when compared to group 1. Comparing symptom clusters, the appearance of motor dysfunction during the current relapse was significantly more frequent in group 2 than in group 1. The overall dose of MPS treatment was significantly lower in group 2 than in group 1 with a similar treatment response in both groups. Conclusions: The substantial clinical-radiological mismatch during acute relapse in our study could be explained by several factors, including a psychosomatic component or disturbance of network connectivity. Alternatively, secondary progression or a diffuse neuro-inflammatory process might cause clinical symptoms, especially in older patients with a longer disease duration. As a consequence, treatment of clinical relapses and the definition of breakthrough disease should be reconsidered in regard to combined clinical and MRI criteria and/or additional biomarkers. Further studies are necessary to address the contribution of diffuse neuro-inflammation to the clinical presentation of symptoms.
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- 2023
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26. Iron and Manganese Alginate for Rechargeable Battery Electrodes
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Lindah K. Kiriinya, Markus C. Kwakernaak, Simone C. D. Van den Akker, Guy L. M. M. Verbist, Stephen J. Picken, and Erik M. Kelder
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alginates ,Polymers and Plastics ,polysaccharide ,General Chemistry ,electrode material ,rechargeable battery - Abstract
We present a sustainable, inherently safe battery chemistry that is based on widely available and cheap materials, that is, iron and manganese hosted in alginate bio-material known from the food and medical industry. The resulting battery can be recycled to allow circularity. The electrodes were synthesised by the alginate caging the multi-valent metals to form a hydrogel in an aqueous environment. Characterisation includes FTIR, XPS and Mössbauer spectroscopy. The electrochemical performance of the electrodes was investigated by performing cyclic voltammetry (CV) and (dis)charge experiments. Mn and Fe ions show good co-ordination with the alginic acid with higher oxidation states demonstrating complex bonding behaviour. The non-optimised iron and manganese alginate electrodes already exhibit a cycling efficiency of 98% and 69%, respectively. This work shows that Fe and Mn atomically disperse in a bio-based host material and can act as electrodes in an aqueous battery chemistry. While demonstrated at cell level, it is furthermore explained how these materials can form the basis for a (semi-solid) flow cell.
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- 2023
27. The MerR-family regulator NmlR is involved in the defense against oxidative stress in Streptococcus pneumoniae
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Verena Nadin Fritsch, Nico Linzner, Tobias Busche, Nelly Said, Christoph Weise, Jörn Kalinowski, Markus C. Wahl, and Haike Antelmann
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Streptococcus pneumoniae ,H2O2 ,Life Sciences Building Blocks of Life Structure and Function ,NmlR ,HOCl ,500 Naturwissenschaften und Mathematik::570 Biowissenschaften ,Biologie::570 Biowissenschaften ,Biologie ,Molecular Biology ,Microbiology ,thiol switches - Abstract
Streptococcus pneumoniae has to cope with the strong oxidant hypochlorous acid (HOCl), during host–pathogen interactions. Thus, we analyzed the global gene expression profile of S. pneumoniae D39 towards HOCl stress. In the RNA-seq transcriptome, the NmlR, SifR, CtsR, HrcA, SczA and CopY regulons and the etrx1-ccdA1-msrAB2 operon were most strongly induced under HOCl stress, which participate in the oxidative, electrophile and metal stress response in S. pneumoniae. The MerR-family regulator NmlR harbors a conserved Cys52 and controls the alcohol dehydrogenase-encoding adhC gene under carbonyl and NO stress. We demonstrated that NmlR senses also HOCl stress to activate transcription of the nmlR-adhC operon. HOCl-induced transcription of adhC required Cys52 of NmlR in vivo. Using mass spectrometry, NmlR was shown to be oxidized to intersubunit disulfides or S-glutathionylated under oxidative stress in vitro. A broccoli-FLAP-based assay further showed that both NmlR disulfides significantly increased transcription initiation at the nmlR promoter by RNAP in vitro, which depends on Cys52. Phenotype analyses revealed that NmlR functions in the defense against oxidative stress and promotes survival of S. pneumoniae during macrophage infections. In conclusion, NmlR was characterized as HOCl-sensing transcriptional regulator, which activates transcription of adhC under oxidative stress by thiol switches in S. pneumoniae.
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- 2023
- Full Text
- View/download PDF
28. Extended DNA threading through a dual-engine motor module of the activating signal co-integrator 1 complex
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Junqiao Jia, Tarek Hilal, Katherine E. Bohnsack, Aleksandar Chernev, Ning Tsao, Juliane Bethmann, Aruna Arumugam, Lane Parmely, Nicole Holton, Bernhard Loll, Nima Mosammaparast, Markus T. Bohnsack, Henning Urlaub, and Markus C. Wahl
- Subjects
Multidisciplinary ,DNA repair enzymes ,Cryoelectron microscopy ,Enzyme mechanisms ,General Physics and Astronomy ,500 Naturwissenschaften und Mathematik::570 Biowissenschaften ,Biologie::570 Biowissenschaften ,Biologie ,General Chemistry ,DNA ,General Biochemistry, Genetics and Molecular Biology - Abstract
Activating signal co-integrator 1 complex (ASCC) subunit 3 (ASCC3) supports diverse genome maintenance and gene expression processes, and contains tandem Ski2-like NTPase/helicase cassettes crucial for these functions. Presently, the molecular mechanisms underlying ASCC3 helicase activity and regulation remain unresolved. We present cryogenic electron microscopy, DNA-protein cross-linking/mass spectrometry as well as in vitro and cellular functional analyses of the ASCC3-TRIP4 sub-module of ASCC. Unlike the related spliceosomal SNRNP200 RNA helicase, ASCC3 can thread substrates through both helicase cassettes. TRIP4 docks on ASCC3 via a zinc finger domain and stimulates the helicase by positioning an ASC-1 homology domain next to the C-terminal helicase cassette of ASCC3, likely supporting substrate engagement and assisting the DNA exit. TRIP4 binds ASCC3 mutually exclusively with the DNA/RNA dealkylase, ALKBH3, directing ASCC3 for specific processes. Our findings define ASCC3-TRIP4 as a tunable motor module of ASCC that encompasses two cooperating NTPase/helicase units functionally expanded by TRIP4.
- Published
- 2023
29. Constraints for precise and accurate fluid inclusion stable isotope analysis using water-vapour saturated CRDS techniques
- Author
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Therese Weissbach, Tobias Kluge, Stéphane Affolter, Markus C. Leuenberger, Hubert Vonhof, Dana F.C. Riechelmann, Jens Fohlmeister, Marie-Christin Juhl, Benedikt Hemmer, Yao Wu, Sophie F. Warken, Martina Schmidt, Norbert Frank, and Werner Aeschbach
- Subjects
Physics - Geophysics ,Geochemistry and Petrology ,FOS: Physical sciences ,Geology ,Geophysics (physics.geo-ph) - Abstract
Hydrogen (δ2H) and oxygen (δ18O) isotopes of water extracted from speleothem fluid inclusions are important proxies used for paleoclimate reconstruction. In our study we use a cavity ring-down laser spectroscopy system for analysis and modified the approach of Affolter et al. (2014) for sample extraction. The method is based on crushing of small sub-gram speleothem samples in a heated and continuously water-vapour purged extraction line. The following points were identified: Injection of reference water shows a precision (1σ) of 0.4–0.5 ‰ for δ18O values and 1.1–1.9 ‰ for δ2H values for water amounts of 0.1–0.5 μl, which improves with increasing water amount to 0.1–0.3 ‰ and 0.2–0.7 ‰, respectively, above 1 μl. The accuracy of measurements of water injections and water-filled glass capillaries crushed in the system is better than 0.08 ‰ for δ18O and 0.3 ‰ for δ2H values. The reproducibility (1σ) based on replicate analysis of speleothem fluid inclusion samples with water amounts >0.2 μl is 0.5 ‰ for δ18O and 1.2 ‰ for δ2H values, respectively. Isotopic differences between the water vapour background of the extraction system and the fluid inclusions have no significant impact on the measured fluid inclusion isotope values if they are within 10 ‰ for δ18O and 50 ‰ for δ2H values of the background. Tests of potential adsorption effects with inclusion free spar calcite confirm that the isotope values are unaffected by adsorption for water contents of about 1 μl (fluid inclusion) water per g of carbonate or above. Fluid inclusion analysis on three different modern to late Holocene speleothems from caves in northwest Germany resulted in δ18O and δ2H values that follow the relationship as defined by the meteoric water line and that correspond to the local drip water. Yet, due to potential isotope exchange reactions for oxygen atoms, hydrogen isotope measurements are preferentially to be used for temperature reconstructions. We demonstrate this in a case study with a Romanian stalagmite, for which we reconstruct the 20th century warming with an amplitude of approximately 1 °C, with a precision for each data point of better than ±0.5 °C.
- Published
- 2023
30. The Effects of Relative Performance Information and Training Type on Employees’ Skill Development: An Experimental Investigation
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Markus C. Arnold, Bei Shi, Ivo Tafkov, and Elien Voermans
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History ,Polymers and Plastics ,Business and International Management ,Industrial and Manufacturing Engineering - Published
- 2023
- Full Text
- View/download PDF
31. Materials Advances / N,N′-Substituted quinacridones for organic electronic device applications
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Saadi, Donia, Mayr, Felix, Yumusak, Cigdem, Wielend, Dominik, Cobet, Munise, Kahraman, Bilge, Irimia, Cristian Vlad, Kanbur, Yasin, Bednorz, Mateusz, Kotwica, Kamil, Fredj, Amel Bel, Romdhane, Samir, Scharber, Markus C., Sariciftci, Niyazi Serdar, and Irimia-Vladu, Mihai
- Abstract
N,N′-Substituted quinacridones are a novel class of commercially available quinacridones for organic electronics which are reported here. In this study, we performed in-depth investigations of the material properties of these molecules i.e. their optical and charge transport properties, infrared-active vibrations (FTIR), electrochemical reduction and oxidation properties, thin film forming and processability, and finally performance in organic field effect transistor devices. We show that substitution plays a critical role in the charge transport properties, with methyl substituted amine being the most favorable, followed by di-phenyl and finally di-butyl. Osterreichische Forschungsforderungsgesellschaft 888408 Version of record
- Published
- 2023
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- View/download PDF
32. Broadband Photon Harvesting in Organic Photovoltaic Devices Induced by Large-Area Nanogrooved Templates
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Debasree Chowdhury, Shaimaa A. Mohamed, Giacomo Manzato, Beatrice Siri, Roberto Chittofrati, Maria Caterina Giordano, Mohamed Hussein, Mohamed F. O. Hameed, Salah S. A. Obayya, Philipp Stadler, Markus C. Scharber, Giuseppe Della Valle, and Francesco Buatier de Mongeot
- Subjects
General Materials Science ,ddc:620 ,Engineering & allied operations - Abstract
Thin-film organic photovoltaic (OPV) devices represent an attractive alternative to conventional silicon solar cells due to their lightweight, flexibility, and low cost. However, the relatively low optical absorption of the OPV active layers still represents an open issue in view of efficient devices that cannot be addressed by adopting conventional light coupling strategies derived from thick PV absorbers. The light coupling to thin-film solar cells can be boosted by nanostructuring the device interfaces at the subwavelength scale. Here, we demonstrate broadband and omnidirectional photon harvesting in thin-film OPV devices enabled by highly ordered one-dimensional (1D) arrays of nanogrooves. Laser interference lithography, in combination with reactive ion etching (RIE), provides the controlled tailoring of the height and periodicity of the silica grooves, enabling effective tuning of the anti-reflection properties in the active organic layer (PTB7:PCBM). With this strategy, we demonstrate a strong enhancement of the optical absorption, as high as 19% with respect to a flat device, over a broadband visible and near-infrared spectrum. The OPV device supported on these optimized nanogrooved substrates yields a 14% increase in short-circuit current over the corresponding flat device, highlighting the potential of this large-scale light-harvesting strategy in the broader context of thin-film technologies.
- Published
- 2023
33. Constraints for precise and accurate fluid inclusion stable isotope analysis using water-vapour saturated CRDS techniques
- Author
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Weissbach, Therese, Kluge, Tobias, Affolter, Stéphane, Leuenberger, Markus C., Vonhof, Hubert, Riechelmann, Dana F. C., Fohlmeister, Jens, Juhl, Marie-Christin, Hemmer, Benedikt, Wu, Yao, Warken, Sophie F., Schmidt, Martina, Frank, Norbert, and Aeschbach, Werner
- Subjects
cavity-ring-down measurement ,Geography & travel ,water isotopes ,speleothems ,paleoclimate ,laser spectroscopy ,small samples ,ddc:910 - Abstract
Hydrogen (δ2H) and oxygen (δ18O) isotopes of water extracted from speleothem fluid inclusions are important proxies used for paleoclimate reconstruction. In our study we use a cavity ring-down laser spectroscopy system for analysis and modified the approach of Affolter et al. (2014) for sample extraction. The method is based on crushing of small sub-gram speleothem samples in a heated and continuously water-vapour purged extraction line. The following points were identified: Injection of reference water shows a precision (1σ) of 0.4-0.5 permil for δ18O values and 1.1-1.9 permil for δ2H values for water amounts of 0.1-0.5 μl, which improves with increasing water amount to 0.1-0.3 permil and 0.2-0.7 permil, respectively, above 1 μl. The accuracy of measurements of water injections and water-filled glass capillaries crushed in the system is better than 0.08 permil for δ18O and 0.3 permil for δ2H values. The reproducibility (1σ) based on replicate analysis of speleothem fluid inclusion samples with water amounts > 0.2 μl is 0.5 permil for δ18O and 1.2 permil for δ2H values, respectively. Isotopic differences between the water vapour background of the extraction system and the fluid inclusions have no significant impact on the measured fluid inclusion isotope values if they are within 10 permil for δ18O and 50 permil for δ2H values of the background. Tests of potential adsorption effects with inclusion free spar calcite confirm that the isotope values are unaffected by adsorption for water contents of about 1 μl (fluid inclusion) water per g of carbonate or above. Fluid inclusion analysis on three different modern to late Holocene speleothems from caves in northwest Germany resulted in δ18O and δ2H values that follow the relationship as defined by the meteoric water line and that correspond to the local drip water. Yet, due to potential isotope exchange reactions for oxygen atoms, hydrogen isotope measurements are preferentially to be used for temperature reconstructions. We demonstrate this in a case study with a Romanian stalagmite, for which we reconstruct the 20th century warming with an amplitude of approximately 1 °C, with a precision for each data point of better than ±0.5 °C
- Published
- 2023
- Full Text
- View/download PDF
34. Preclinical Assessment of Bacteriophage Therapy against Experimental Acinetobacter baumannii Lung Infection
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Sandra-Maria Wienhold, Markus C. Brack, Geraldine Nouailles, Gopinath Krishnamoorthy, Imke H. E. Korf, Claudius Seitz, Sarah Wienecke, Kristina Dietert, Corinne Gurtner, Olivia Kershaw, Achim D. Gruber, Anton Ross, Holger Ziehr, Manfred Rohde, Jens Neudecker, Jasmin Lienau, Norbert Suttorp, Stefan Hippenstiel, Andreas C. Hocke, Christine Rohde, Martin Witzenrath, and Publica
- Subjects
Acinetobacter baumannii ,Infectious Diseases ,antibiotic resistance ,bacteriophage ,Virology ,pneumonia ,600 Technik, Medizin, angewandte Wissenschaften::610 Medizin und Gesundheit::616 Krankheiten ,preclinical development ,Microbiology ,QR1-502 - Abstract
Respiratory infections caused by multidrug-resistant Acinetobacter baumannii are difficult to treat and associated with high mortality among critically ill hospitalized patients. Bacteriophages (phages) eliminate pathogens with high host specificity and efficacy. However, the lack of appropriate preclinical experimental models hampers the progress of clinical development of phages as therapeutic agents. Therefore, we tested the efficacy of a purified lytic phage, vB_AbaM_Acibel004, against multidrug-resistant A. baumannii clinical isolate RUH 2037 infection in immunocompetent mice and a human lung tissue model. Sham- and A. baumannii-infected mice received a single-dose of phage or buffer via intratracheal aerosolization. Group-specific differences in bacterial burden, immune and clinical responses were compared. Phage-treated mice not only recovered faster from infection-associated hypothermia but also had lower pulmonary bacterial burden, lower lung permeability, and cytokine release. Histopathological examination revealed less inflammation with unaffected inflammatory cellular recruitment. No phage-specific adverse events were noted. Additionally, the bactericidal effect of the purified phage on A. baumannii was confirmed after single-dose treatment in an ex vivo human lung infection model. Taken together, our data suggest that the investigated phage has significant potential to treat multidrug-resistant A. baumannii infections and further support the development of appropriate methods for preclinical evaluation of antibacterial efficacy of phages.
- Published
- 2022
35. Tumefactive demyelinating CNS lesion in a 60-year-old woman with familial Mediterranean fever
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Markus C. Kowarik, Till-Karsten Hauser, Ulf Ziemann, Constanze Trostel, Kornelia Laichinger, Jörg Henes, Sebastian Jonas Saur, and Markus Krumbholz
- Subjects
In vivo magnetic resonance spectroscopy ,Pathology ,medicine.medical_specialty ,Multiple Sclerosis ,Magnetic Resonance Spectroscopy ,Contrast enhancement ,Central nervous system ,Familial Mediterranean fever ,Choline ,Lesion ,medicine ,Humans ,Lactic Acid ,business.industry ,Multiple sclerosis ,Cns lesion ,General Medicine ,Middle Aged ,medicine.disease ,Magnetic Resonance Imaging ,Familial Mediterranean Fever ,ddc ,medicine.anatomical_structure ,Concomitant ,Main Topic ,Familiar Mediterranean fever ,Demyelination ,Tumefactive CNS lesion ,MR spectroscopy ,Familiäres Mittelmeerfieber ,Demyelinisierung ,Tumefaktive ZNS-Läsion ,Multiple Sklerose ,MR-Spektroskopie ,Female ,medicine.symptom ,business - Abstract
We here report on a 60-year-old woman with familial Mediterranean fever (FMF) who developed cognitive impairment 16 years after initial diagnosis. On MRI, a new extensive white matter lesion in the right frontal lobe with mild local mass effect but without contrast enhancement was detectable and classified as a tumefactive lesion. Additional MR spectroscopy showed markedly increased choline levels accompanied by a significant lactate peak, highly suggestive of a low-florid demyelinating process. Although diffuse central nervous system (CNS) lesions have been described in single FMF cases, tumefactive lesions have not been observed in FMF patients without concomitant multiple sclerosis. In summary, this case highlights rare differential diagnoses of atypical, inflammatory CNS lesions and the clinical utility of MR spectroscopy.Die Autoren berichten in dem vorgestellten Fall von einer 60-jährigen Frau mit vorbekanntem familiärem Mittelmeerfieber (FMF), die 16 Jahre nach Diagnosestellung subakut kognitive Defizite entwickelt hatte. In der Bildgebung mittels Magnetresonanztomographie (MRT) zeigte sich als mögliche Erklärung dafür eine neue, frontal rechts gelegene Läsion mit leichtem Masseneffekt, aber ohne Kontrastmittelaufnahme, die als tumefaktive Läsion eingestuft wurde. Eine ergänzende MR-Spektroskopie zeigte einen deutlich erhöhten Cholin-Peak zusammen mit einem Laktat-Peak, was einen niedrigfloriden demyelinisierenden Prozess nahelegte. Auch wenn diffuse Läsionen des zentralen Nervensystems (ZNS) bei FMF vorbekannt sind, so wurden bislang tumefaktive Läsionen bei FMF ohne begleitende Multiple Sklerose nicht beschrieben. Zusammenfassend werden anhand dieses Falls seltene Differenzialdiagnosen von atypischen ZNS-Läsionen und der klinische Nutzen der MR-Spektroskopie hervorgehoben.
- Published
- 2021
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- View/download PDF
36. Author Correction: Wheat Pm4 resistance to powdery mildew is controlled by alternative splice variants encoding chimeric proteins
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Javier Sánchez-Martín, Victoria Widrig, Gerhard Herren, Thomas Wicker, Helen Zbinden, Julien Gronnier, Laurin Spörri, Coraline R. Praz, Matthias Heuberger, Markus C. Kolodziej, Jonatan Isaksson, Burkhard Steuernagel, Miroslava Karafiátová, Jaroslav Doležel, Cyril Zipfel, and Beat Keller
- Subjects
Plant Science - Published
- 2023
- Full Text
- View/download PDF
37. Fluorogenic RNA aptamers to probe transcription initiation and co-transcriptional RNA folding by multi-subunit RNA polymerases
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Yong-Heng, Huang, Vilma, Trapp, Oskari, Puro, Janne J, Mäkinen, Mikko, Metsä-Ketelä, Markus C, Wahl, and Georgiy A, Belogurov
- Subjects
RNA Folding ,Green Fluorescent Proteins ,RNA ,DNA-Directed RNA Polymerases ,Aptamers, Nucleotide ,Fluorescent Dyes - Abstract
Transcription is the first and most highly regulated step in gene expression. Experimental techniques for monitoring transcription are, thus, important for studying gene expression and gene regulation as well as for translational research and drug development. Fluorescence methods are often superior to other techniques for real-time monitoring of biochemical processes. Green fluorescent proteins have long served as valuable tools for studying the process of translation. Here we present two methods that utilize fluorescent light-up RNA aptamers (FLAPs), the RNA mimics of green fluorescent proteins, to monitoring transcription and co-transcriptional RNA folding. FLAPs adopt defined three-dimensional folds that bind low molecular weight compounds called fluorogens with concomitant increase in fluorescence by many folds. FLAPs provide a strong fluorescence signal with low background that allows monitoring of transcription in real time in vitro and in vivo. However, it takes several seconds for RNA polymerase to synthesize FLAPs and the subsequent folding of the fluorogen-binding platform takes additional seconds or minutes. Here we show that Broccoli-FLAP is well suited for monitoring the rate of transcription initiation in a multi-round setup that mitigates the slow rate of the FLAP maturation. Furthermore, we demonstrate that a relatively slow and inefficient folding of iSpinach-FLAP can be taken advantage of for monitoring the action of RNA folding chaperones.
- Published
- 2022
38. TRoponin of Unknown origin in STroke evaluated by multi-component cardiac Magnetic resonance Imaging – The TRUST-MI study
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Mengel, Annerose, Nenova, Lilyana, Müller, Karin A. L., Poli, Sven, Kowarik, Markus C., Feil, Katharina, Mizera, Lars, Geisler, Tobias, Kübler, Jens, Mahrholdt, Heiko, Ernemann, Ulrike, Hennersdorf, Florian, Ziemann, Ulf, Nikolaou, Konstantin, Gawaz, Meinrad, Krumm, Patrick, and Greulich, Simon
- Subjects
Cardiology and Cardiovascular Medicine - Published
- 2022
- Full Text
- View/download PDF
39. Branch point evolution controls species-specific alternative splicing and regulates long term potentiation
- Author
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Andreas Franz, A. Ioana Weber, Marco Preußner, Nicole Dimos, Alexander Stumpf, Yanlong Ji, Laura Moreno-Velasquez, Anne Voigt, Frederic Schulz, Alexander Neumann, Benno Kuropka, Ralf Kühn, Henning Urlaub, Dietmar Schmitz, Markus C. Wahl, and Florian Heyd
- Subjects
Cancer Research ,Technology Platforms ,Function and Dysfunction of the Nervous System - Abstract
Regulation and functionality of species-specific alternative splicing has remained enigmatic to the present date. Calcium/calmodulin-dependent protein kinase IIβ (CaMKIIβ) is expressed in several splice variants and plays a key role in learning and memory. Here, we identify and characterize several primate-specific CAMK2B splice isoforms, which show altered kinetic properties and changes in substrate specificity. Furthermore, we demonstrate that primate-specific Camk2β alternative splicing is achieved through branch point weakening during evolution. We show that reducing branch point and splice site strengths during evolution globally renders constitutive exons alternative, thus providing a paradigm for cis-directed species-specific alternative splicing regulation. Using CRISPR/Cas9 we introduced a weaker human branch point into the mouse genome, resulting in human-like CAMK2B splicing in the brain of mutant mice. We observe a strong impairment of long-term potentiation in CA3-CA1 synapses of mutant mice, thus connecting branch point-controlled, species-specific alternative splicing with a fundamental function in learning and memory.
- Published
- 2022
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- View/download PDF
40. The Oncolytic Adenovirus XVir-N-31, in Combination with the Blockade of the PD-1/PD-L1 Axis, Conveys Abscopal Effects in a Humanized Glioblastoma Mouse Model
- Author
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Naumann, Moritz Klawitter, Ali El-Ayoubi, Jasmin Buch, Jakob Rüttinger, Maximilian Ehrenfeld, Eva Lichtenegger, Marcel A. Krüger, Klaus Mantwill, Florestan J. Koll, Markus C. Kowarik, Per Sonne Holm, and Ulrike
- Subjects
glioblastoma ,oncolytic virotherapy ,immune checkpoint inhibition ,abscopal effects ,XVir-N-31 - Abstract
Glioblastoma (GBM) is an obligatory lethal brain tumor with a median survival, even with the best standard of care therapy, of less than 20 months. In light of this fact, the evaluation of new GBM treatment approaches such as oncolytic virotherapy (OVT) is urgently needed. Based on our preliminary preclinical data, the YB-1 dependent oncolytic adenovirus (OAV) XVir-N-31 represents a promising therapeutic agent to treat, in particular, therapy resistant GBM. Preclinical studies have shown that XVir-N-31 prolonged the survival of GBM bearing mice. Now using an immunohumanized mouse model, we examined the immunostimulatory effects of XVir-N-31 in comparison to the wildtype adenovirus (Ad-WT). Additionally, we combined OVT with the inhibition of immune checkpoint proteins by using XVir-N-31 in combination with nivolumab, or by using a derivate of XVir-N-31 that expresses a PD-L1 neutralizing antibody. Although in vitro cell killing was higher for Ad-WT, XVir-N-31 induced a much stronger immunogenic cell death that was further elevated by blocking PD-1 or PD-L1. In vivo, an intratumoral injection of XVir-N-31 increased tumor infiltrating lymphocytes (TILs) and NK cells significantly more than Ad-WT not only in the virus-injected tumors, but also in the untreated tumors growing in the contralateral hemisphere. This suggests that for an effective treatment of GBM, immune activating properties by OAVs seem to be of greater importance than their oncolytic capacity. Furthermore, the addition of immune checkpoint inhibition (ICI) to OVT further induced lymphocyte infiltration. Consequently, a significant reduction in contralateral non-virus-injected tumors was only visible if OVT was combined with ICI. This strongly indicates that for an effective eradication of GBM cells that cannot be directly targeted by an intratumoral OV injection, additional ICI therapy is required.
- Published
- 2022
- Full Text
- View/download PDF
41. Treatment of progressive multiple sclerosis with high-dose all-trans retinoic acid – no clear evidence of positive disease modifying effects
- Author
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Marcus M Schittenhelm, Maria-Ioanna Stefanou, Felix Bischof, Evelyn Dubois, Markus C. Kowarik, Markus Krumbholz, Ulf Ziemann, and Christoph Ruschil
- Subjects
0301 basic medicine ,Acute promyelocytic leukemia ,medicine.medical_specialty ,Neurology ,medicine.medical_treatment ,Lymphocyte subsets ,Retinoic acid ,Neurosciences. Biological psychiatry. Neuropsychiatry ,Peripheral blood mononuclear cell ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,medicine ,Cytotoxic T cell ,Vitamin A ,RC346-429 ,B cell ,Chemotherapy ,business.industry ,All-trans retinoic acid ,Multiple sclerosis ,medicine.disease ,030104 developmental biology ,medicine.anatomical_structure ,chemistry ,Immunology ,Neurology. Diseases of the nervous system ,Progressive multiple sclerosis ,business ,030217 neurology & neurosurgery ,Research Article ,RC321-571 - Abstract
Background All-trans retinoic acid (ATRA) is an acid derivative of vitamin A which is discussed as a promising candidate to ameliorate the disease course of multiple sclerosis (MS) by immunomodulation or even by promoting regeneration in progressive MS. Here we report a patient who significantly improved for MS related disability following administration of chemotherapy including ATRA for mitoxantrone-related acute promyelocytic leukemia and assess the effect of high-dose ATRA in three additional patients with progressive MS. Methods Patients with progressive MS who had failed previous therapies were treated with high-dose ATRA. Patients underwent clinical and routine laboratory monitoring. Additionally, PBMCs were analyzed by flow cytometry for lymphocyte subsets. Results ATRA was well tolerated and no pathological laboratory abnormalities were observed. After initial mild (not statistically significant) improvement of EDSS and mean MSFC z-score, ongoing disease progression was observed. One patient subacutely experienced severe cognitive and motor worsening. Cerebral MRI revealed persistent gadolinium-enhancing lesions. Flow cytometric alterations of peripheral blood naïve, central memory and effector memory CD4 and CD8 T cells, B lymphocytes, plasma cells, memory B cells, plasmablasts and natural killer (NK) cells did not reach statistical significance. Conclusions Stand-alone therapy with ATRA did not ameliorate progressive MS in our limited cohort and we did not observe consistent alterations of T and B cell subsets. Intriguingly, application of ATRA may have caused marked disease exacerbation in one patient.
- Published
- 2021
42. Do Job Candidates' Effort Promises Matter When the Labor Market is Competitive? Experimental Evidence
- Author
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Robert A. Grasser and Markus C. Arnold
- Subjects
media_common.quotation_subject ,Perspective (graphical) ,Affect (psychology) ,ComputingMethodologies_ARTIFICIALINTELLIGENCE ,Microeconomics ,Competition (economics) ,Bargaining power ,Principal (commercial law) ,Accounting ,Perception ,Selection (linguistics) ,Relevance (law) ,Business ,Business and International Management ,media_common - Abstract
Using an experiment, we investigate whether job candidates' noncontractible effort promises increase their actual effort in the work relationship when the labor market is competitive. Due to promise-keeping preferences, individuals tend to keep promises even if doing so is costly. However, when promises can be made strategically to influence hiring decisions, it is unclear whether workers are less likely to keep their promises. We develop theory to predict that making effort promises matters even more when labor markets are competitive. We find workers promise higher effort levels when competing for jobs than when they do not, but do not keep promises to a lesser extent although the costs of promise-keeping increase with the promise size, thereby increasing the total effort provided. The results enhance our understanding of the effects of worker-employer communication during hiring, particularly in a competitive setting in which such communication is most likely to occur.
- Published
- 2021
- Full Text
- View/download PDF
43. Pfalz Werla – Die Ausgrabung von Tor II aus dem 10. Jahrhundert und seine Visualisierung 2012
- Author
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Blaich, Markus C., Geschwinde, Michael, and Lowes, Christoph
- Abstract
Burgen und Schlösser - Zeitschrift für Burgenforschung und Denkmalpflege, Bd. 54 Nr. 1 (2013): Burgen und Schlösser. Zeitschrift für Burgenforschung und Denkmalpflege
- Published
- 2022
- Full Text
- View/download PDF
44. The Role of Vascular Risk Factors in Post-Stroke Delirium: A Systematic Review and Meta-Analysis
- Author
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Vasileios, Siokas, Robert, Fleischmann, Katharina, Feil, Ioannis, Liampas, Markus C, Kowarik, Yang, Bai, Maria-Ioanna, Stefanou, Sven, Poli, Ulf, Ziemann, Efthimios, Dardiotis, and Annerose, Mengel
- Abstract
Vascular risk factors may predispose to post-stroke delirium (PSD). A systematic review and meta-analysis were performed by searching PubMed, Web of Science, and Scopus. The primary outcome was the prevalence of vascular risk factors in PSD vs. non-PSD patients. Odds ratios (ORs) with 95% confidence intervals (CIs) and mean differences (MDs) with 95% CIs were calculated for categorical and continuous variables, respectively. Fixed effects or random effects models were used in case of low- or high-statistical heterogeneity, respectively. We found an increased prevalence of atrial fibrillation (OR = 1.74
- Published
- 2022
45. Matthias Hardt: Gold und Herrschaft. Die Schätze europäischer Könige und Fürsten im ersten Jahrtausend. Europa im Mittelalter
- Author
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Blaich, Markus C.
- Abstract
Rezension zu: Matthias Hardt: Gold und Herrschaft. Die Schätze europäischer Könige und Fürsten im ersten Jahrtausend. Europa im Mittelalter. Bd. 6, Akademie Verlag. Berlin 2004. 369 Seiten, 20 Abbildungen., Jahresschrift für mitteldeutsche Vorgeschichte, Bd. 89 (2005): Jahresschrift für Mitteldeutsche Vorgeschichte
- Published
- 2022
- Full Text
- View/download PDF
46. The Oncolytic Adenovirus XVir-N-31, in Combination with the Blockade of the PD-1/PD-L1 Axis, Conveys Abscopal Effects in a Humanized Glioblastoma Mouse Model
- Author
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Moritz, Klawitter, Ali, El-Ayoubi, Jasmin, Buch, Jakob, Rüttinger, Maximilian, Ehrenfeld, Eva, Lichtenegger, Marcel A, Krüger, Klaus, Mantwill, Florestan J, Koll, Markus C, Kowarik, Per Sonne, Holm, and Ulrike, Naumann
- Subjects
Oncolytic Virotherapy ,Disease Models, Animal ,Mice ,Cell Line, Tumor ,Programmed Cell Death 1 Receptor ,Animals ,Glioblastoma ,B7-H1 Antigen ,Adenoviridae - Abstract
Glioblastoma (GBM) is an obligatory lethal brain tumor with a median survival, even with the best standard of care therapy, of less than 20 months. In light of this fact, the evaluation of new GBM treatment approaches such as oncolytic virotherapy (OVT) is urgently needed. Based on our preliminary preclinical data, the YB-1 dependent oncolytic adenovirus (OAV) XVir-N-31 represents a promising therapeutic agent to treat, in particular, therapy resistant GBM. Preclinical studies have shown that XVir-N-31 prolonged the survival of GBM bearing mice. Now using an immunohumanized mouse model, we examined the immunostimulatory effects of XVir-N-31 in comparison to the wildtype adenovirus (Ad-WT). Additionally, we combined OVT with the inhibition of immune checkpoint proteins by using XVir-N-31 in combination with nivolumab, or by using a derivate of XVir-N-31 that expresses a PD-L1 neutralizing antibody. Although in vitro cell killing was higher for Ad-WT, XVir-N-31 induced a much stronger immunogenic cell death that was further elevated by blocking PD-1 or PD-L1. In vivo, an intratumoral injection of XVir-N-31 increased tumor infiltrating lymphocytes (TILs) and NK cells significantly more than Ad-WT not only in the virus-injected tumors, but also in the untreated tumors growing in the contralateral hemisphere. This suggests that for an effective treatment of GBM, immune activating properties by OAVs seem to be of greater importance than their oncolytic capacity. Furthermore, the addition of immune checkpoint inhibition (ICI) to OVT further induced lymphocyte infiltration. Consequently, a significant reduction in contralateral non-virus-injected tumors was only visible if OVT was combined with ICI. This strongly indicates that for an effective eradication of GBM cells that cannot be directly targeted by an intratumoral OV injection, additional ICI therapy is required.
- Published
- 2022
47. Zur Diskussion um die Baugeschichte des 'Kaiserhauses' in der Pfalz Goslar
- Author
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Blaich, Markus C.
- Abstract
Burgen und Schlösser - Zeitschrift für Burgenforschung und Denkmalpflege, Bd. 54 Nr. 2 (2013): Burgen und Schlösser. Zeitschrift für Burgenforschung und Denkmalpflege
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- 2022
- Full Text
- View/download PDF
48. TRoponin of Unknown origin in STroke evaluated by multi-component cardiac Magnetic resonance Imaging - The TRUST-MI study
- Author
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Annerose, Mengel, Lilyana, Nenova, Karin A L, Müller, Sven, Poli, Markus C, Kowarik, Katharina, Feil, Lars, Mizera, Tobias, Geisler, Jens, Kübler, Heiko, Mahrholdt, Ulrike, Ernemann, Florian, Hennersdorf, Ulf, Ziemann, Konstantin, Nikolaou, Meinrad, Gawaz, Patrick, Krumm, and Simon, Greulich
- Abstract
Increased high-sensitive cardiac troponin I (hs-cTnI) levels are common in patients with acute ischemic stroke. However, only a minority demonstrates culprit lesions on coronary angiography, suggesting other mechanisms, e.g., inflammation, as underlying cause of myocardial damage. Late Gadolinium Enhancement (LGE)-cardiac magnetic resonance (CMR) with mapping techniques [T1, T2, extracellular volume (ECV)] allow the detection of both focal and diffuse myocardial abnormalities. We investigated the prevalence of culprit lesions by coronary angiography and myocardial tissue abnormalities by a comprehensive CMR protocol in troponin-positive stroke patients.Patients with troponin-positive acute ischemic stroke and no history of coronary artery disease were prospectively enrolled. Coronary angiography and CMR (LGE, T1 + T2 mapping, ECV) were performed within the first days of the acute stroke. Twenty-five troponin-positive patients (mean age 62 years, 44% females) were included. 2 patients (8%) had culprit lesions on coronary angiography and underwent percutaneous coronary intervention. 13 patients (52%) demonstrated LGE: (i)Our data show a low prevalence of culprit lesions in troponin-positive stroke patients. However,50% of the patients demonstrated myocardial scars (ischemic + non-ischemic) by LGE-CMR. Mapping revealed additional myocardial abnormalities (mostly inflammatory) in the majority of LGE-negative patients. Therefore, a comprehensive CMR protocol gives important insights in the etiology of troponin which might have implications for the further work-up of troponin-positive stroke patients.
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- 2022
49. Crystal structures of glycoprotein D of equine alphaherpesviruses reveal potential binding sites to the entry receptor MHC-I
- Author
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Viviane Kremling, Bernhard Loll, Szymon Pach, Ismail Dahmani, Christoph Weise, Gerhard Wolber, Salvatore Chiantia, Markus C. Wahl, Nikolaus Osterrieder, and Walid Azab
- Subjects
Microbiology (medical) ,Microbiology - Abstract
Cell entry of most alphaherpesviruses is mediated by the binding of glycoprotein D (gD) to different cell surface receptors. Equine herpesvirus type 1 (EHV-1) and EHV-4 gDs interact with equine major histocompatibility complex I (MHC-I) to initiate entry into equine cells. We have characterized the gD-MHC-I interaction by solving the crystal structures of EHV-1 and EHV-4 gDs (gD1, gD4), performing protein-protein docking simulations, surface plasmon resonance (SPR) analysis, and biological assays. The structures of gD1 and gD4 revealed the existence of a common V-set immunoglobulin-like (IgV-like) core comparable to those of other gD homologs. Molecular modeling yielded plausible binding hypotheses and identified key residues (F213 and D261) that are important for virus binding. Altering the key residues resulted in impaired virus growth in cells, which highlights the important role of these residues in the gD-MHC-I interaction. Taken together, our results add to our understanding of the initial herpesvirus-cell interactions and will contribute to the targeted design of antiviral drugs and vaccine development.Author summaryEquine herpesvirus type 1 (EHV-1) and type 4 (EHV-4) are endemic in horses and cause great suffering as well as substantial economic losses to the equine industry. Current vaccines do not prevent infections and treatment is difficult. A prerequisite for vaccine and drug development is an in-depth understanding of the virus replication cycle, especially the virus entry process in order to block the infection at early stages. Entry of alphaherpesviruses into the host cell is mediated by a set of virus envelope glycoproteins including glycoprotein D (gD) that triggers the internalization of the virus particle. The structure of gD and the interaction with the entry receptor equine major histocompatibility complex class I (MHC-I) remains elusive. Here, we solved the crystal structures of gD1 and gD4 that allowed us to model virus-receptor interaction and to determine the key residues for virus entry. Alterations of these key residues impaired virus growth in cell culture. The overall structure of gD1 and gD4 shows classical features of other alphaherpesvirus gDs making it possible to gain further insights into human pathogens as well.
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- 2022
- Full Text
- View/download PDF
50. The Unintended Consequences of Headquarters' Involvement in Decentralized Transfer Price Negotiations: Experimental Evidence
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Florian Elsinger, Markus C. Arnold, Frederick W. Rankin, Partnerships Resource Centre, Department of Accounting & Control, and Accounting Group
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050208 finance ,Delegation ,Unintended consequences ,business.industry ,Strategy and Management ,media_common.quotation_subject ,05 social sciences ,Transfer pricing ,050201 accounting ,Management Science and Operations Research ,Public relations ,650 Management & public relations ,330 Economics ,Microeconomics ,Negotiation ,0502 economics and business ,Business ,Inefficiency ,Disadvantage ,Autonomy ,media_common ,Overconfidence effect - Abstract
This study investigates how headquarters involvement affects the efficiency of decentralized transfer price negotiations. Prior research assumes that decentralized managers negotiate transfer prices autonomously. However, evidence suggests that headquarters can become involved in transfer price negotiations, particularly after negotiation failure. While the intention of headquarters involvement is to overcome inefficiencies arising from decentralized managers’ inability to agree on a transfer price, we suggest that such involvement is likely to have the unintended consequences of further reducing both agreement frequency and the efficiency of negotiated transfer pricing. Reduced agreement is likely to occur because decentralized managers are likely to feel less responsible for the negotiation outcome and may be overly optimistic about headquarters’ decision. Reduced efficiency is likely to result because overconfidence is likely to make headquarters underestimate its informational disadvantage compared to decentralized managers and, consequently, induces inefficient transfer decisions. For the same reasons, inefficiency is likely to be the larger, the more decision authority headquarters takes over after negotiation failure. In an experiment, we manipulate whether headquarters involvement is absent vs. present. Nested within headquarters involvement present are two conditions: one where, after negotiation failure, headquarters suggests a transfer price that either decentralized manager can reject (weak involvement) and one where it can impose a price at which they must trade (strong involvement). Consistent with our predictions, we find that headquarters involvement reduces the frequency of negotiation agreement and the efficiency of transfer pricing. Additionally, we find that efficiency is reduced more when headquarters involvement is strong rather than weak. We contribute to the literature on negotiated transfer pricing by providing evidence about headquarters’ biased perceptions of negotiation impasse and the unintended consequences of its involvement. Additionally, our study informs organizations about the benefits of committing to non-involvement in decentralized transfer price negotiations.
- Published
- 2021
- Full Text
- View/download PDF
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