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Hoffmann A. Reliability, validity, and utility of tests and scores. Eur J Prev Cardiol 2024; 31:667. [PMID: 37939792 DOI: 10.1093/eurjpc/zwad345] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/30/2023] [Accepted: 11/02/2023] [Indexed: 11/10/2023]
Affiliation(s)
- Andreas Hoffmann
- Cardiology Department, University of Basel, Socinstrasse 23, Basel CH 4051, Switzerland
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Gauer C, Battis K, Schneider Y, Florio JB, Mante M, Kim HY, Rissman RA, Hoffmann A, Winkler J. CSF1R-mediated myeloid cell depletion shifts the ratio of motor cortical excitatory to inhibitory neurons in a multiple system atrophy model. Exp Neurol 2024; 374:114706. [PMID: 38311020 DOI: 10.1016/j.expneurol.2024.114706] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2023] [Accepted: 01/28/2024] [Indexed: 02/06/2024]
Abstract
Motor cortical circuit functions depend on the coordinated fine-tuning of two functionally diverse neuronal populations: glutamatergic pyramidal neurons providing synaptic excitation and GABAergic interneurons adjusting the response of pyramidal neurons through synaptic inhibition. Microglia are brain resident macrophages which dynamically refine cortical circuits by monitoring perineuronal extracellular matrix and remodelling synapses. Previously, we showed that colony-stimulating factor 1 receptor (CSF1R)-mediated myeloid cell depletion extended the lifespan, but impaired motor functions of MBP29 mice, a mouse model for multiple system atrophy. In order to better understand the mechanisms underlying these motor deficits we characterized the microglial involvement in the cortical balance of GABAergic interneurons and glutamatergic pyramidal neurons in 4-months-old MBP29 mice following CSF1R inhibition for 12 weeks. Lack of myeloid cells resulted in a decreased number of COUP TF1 interacting protein 2-positive (CTIP2+) layer V pyramidal neurons, however in a proportional increase of calretinin-positive GABAergic interneurons in MBP29 mice. While myeloid cell depletion did not alter the expression of important presynaptic and postsynaptic proteins, the loss of cortical perineuronal net area was attenuated by CSF1R inhibition in MBP29 mice. These cortical changes may restrict synaptic plasticity and potentially modify parvalbumin-positive perisomatic input. Collectively, this study suggests, that the lack of myeloid cells shifts the neuronal balance toward an increased inhibitory connectivity in the motor cortex of MBP29 mice thereby potentially deteriorating motor functions.
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Affiliation(s)
- C Gauer
- Department of Molecular Neurology, University Hospital Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), 91054 Erlangen, Germany
| | - K Battis
- Department of Molecular Neurology, University Hospital Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), 91054 Erlangen, Germany
| | - Y Schneider
- Department of Molecular Neurology, University Hospital Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), 91054 Erlangen, Germany
| | - J B Florio
- Department of Neurosciences, University of California-San Diego, La Jolla, CA 92093, USA
| | - M Mante
- Department of Neurosciences, University of California-San Diego, La Jolla, CA 92093, USA
| | - H Y Kim
- Department of Neurosciences, University of California-San Diego, La Jolla, CA 92093, USA
| | - R A Rissman
- Department of Neurosciences, University of California-San Diego, La Jolla, CA 92093, USA
| | - A Hoffmann
- Department of Molecular Neurology, University Hospital Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), 91054 Erlangen, Germany; UK Dementia Research Institute at The University of Edinburgh, Edinburgh, UK; Keenan Research Centre for Biomedical Science and Barlo Multiple Sclerosis Centre, St. Michael's Hospital, Toronto, Ontario, Canada.
| | - J Winkler
- Department of Molecular Neurology, University Hospital Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), 91054 Erlangen, Germany.
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Rothoeft T, Maier C, Talarico A, Hoffmann A, Schlegtendal A, Lange B, Petersmann A, Denz R, Timmesfeld N, Toepfner N, Vidal-Blanco E, Pfaender S, Lücke T, Brinkmann F. Natural and hybrid immunity after SARS-CoV-2 infection in children and adolescents. Infection 2024:10.1007/s15010-024-02225-w. [PMID: 38499828 DOI: 10.1007/s15010-024-02225-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] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2023] [Accepted: 02/24/2024] [Indexed: 03/20/2024]
Abstract
PURPOSE In contrast to adults, immune protection against SARS-CoV-2 in children and adolescents with natural or hybrid immunity is still poorly understood. The aim of this study was to analyze different immune compartments in different age groups and whether humoral immune reactions correlate with a cellular immune response. METHODS 72 children and adolescents with a preceding SARS-CoV-2 infection were recruited. 37 were vaccinated with an RNA vaccine (BNT162b2). Humoral immunity was analyzed 3-26 months (median 10 months) after infection by measuring Spike protein (S), nucleocapsid (NCP), and neutralizing antibodies (nAB). Cellular immunity was analyzed using a SARS-CoV-2-specific interferon-γ release assay (IGRA). RESULTS All children and adolescents had S antibodies; titers were higher in those with hybrid immunity (14,900 BAU/ml vs. 2118 BAU/ml). NCP antibodies were detectable in > 90%. Neutralizing antibodies (nAB) were more frequently detected (90%) with higher titers (1914 RLU) in adolescents with hybrid immunity than in children with natural immunity (62.5%, 476 RLU). Children with natural immunity were less likely to have reactive IGRAs (43.8%) than adolescents with hybrid immunity (85%). The amount of interferon-γ released by T cells was comparable in natural and hybrid immunity. CONCLUSION Spike antibodies are the most reliable markers to monitor an immune reaction against SARS-CoV-2. High antibody titers of spike antibodies and nAB correlated with cellular immunity, a phenomenon found only in adolescents with hybrid immunity. Hybrid immunity is associated with markedly higher antibody titers and a higher probability of a cellular immune response than a natural immunity.
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Affiliation(s)
- T Rothoeft
- University Hospital of Pediatrics and Adolescent Medicine, St. Josef-Hospital, Ruhr-University, Bochum, Germany.
| | - C Maier
- University Hospital of Pediatrics and Adolescent Medicine, St. Josef-Hospital, Ruhr-University, Bochum, Germany
| | - A Talarico
- University Hospital of Pediatrics and Adolescent Medicine, St. Josef-Hospital, Ruhr-University, Bochum, Germany
| | - A Hoffmann
- University Hospital of Pediatrics and Adolescent Medicine, St. Josef-Hospital, Ruhr-University, Bochum, Germany
| | - A Schlegtendal
- University Hospital of Pediatrics and Adolescent Medicine, St. Josef-Hospital, Ruhr-University, Bochum, Germany
| | - B Lange
- Department of Epidemiology, Helmholtz Centre for Infection Research, Brunswick, Germany
| | - A Petersmann
- University Institute of Clinical Chemistry and Laboratory Medicine, University Medicine Oldenburg, Oldenburg, Germany
- University Institute of Clinical Chemistry and Laboratory Medicine, University Medicine Greifswald, Greifswald, Germany
| | - R Denz
- Department of Medical Informatics, Biometry and Epidemiology, Ruhr-University Bochum, Bochum, Germany
| | - N Timmesfeld
- Department of Medical Informatics, Biometry and Epidemiology, Ruhr-University Bochum, Bochum, Germany
| | - N Toepfner
- Department of Pediatrics, Faculty of Medicine, University Hospital Carl Gustav Carus, Technische Universität Dresden, Dresden, Germany
| | - E Vidal-Blanco
- Department of Molecular and Medical Virology, Ruhr University Bochum, Bochum, Germany
| | - S Pfaender
- Department of Molecular and Medical Virology, Ruhr University Bochum, Bochum, Germany
| | - T Lücke
- University Hospital of Pediatrics and Adolescent Medicine, St. Josef-Hospital, Ruhr-University, Bochum, Germany
| | - F Brinkmann
- University Hospital of Pediatrics and Adolescent Medicine, St. Josef-Hospital, Ruhr-University, Bochum, Germany
- University Children's Hospital, Lübeck, Germany
- Airway Research Center North (ARCN), German Center for Lung Research (DZL), Lübeck, Germany
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Schneider Y, Gauer C, Andert M, Hoffmann A, Riemenschneider MJ, Krebs W, Chalmers N, Lötzsch C, Naumann UJ, Xiang W, Rothhammer V, Beckervordersandforth R, Schlachetzki JCM, Winkler J. Distinct forebrain regions define a dichotomous astrocytic profile in multiple system atrophy. Acta Neuropathol Commun 2024; 12:1. [PMID: 38167307 PMCID: PMC10759635 DOI: 10.1186/s40478-023-01699-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2023] [Accepted: 11/28/2023] [Indexed: 01/05/2024] Open
Abstract
The growing recognition of a dichotomous role of astrocytes in neurodegenerative processes has heightened the need for unraveling distinct astrocytic subtypes in neurological disorders. In multiple system atrophy (MSA), a rare, rapidly progressing atypical Parkinsonian disease characterized by increased astrocyte reactivity. However the specific contribution of astrocyte subtypes to neuropathology remains elusive. Hence, we first set out to profile glial fibrillary acidic protein levels in astrocytes across the human post mortem motor cortex, putamen, and substantia nigra of MSA patients and observed an overall profound astrocytic response. Matching the post mortem human findings, a similar astrocytic phenotype was present in a transgenic MSA mouse model. Notably, MSA mice exhibited a decreased expression of the glutamate transporter 1 and glutamate aspartate transporter in the basal ganglia, but not the motor cortex. We developed an optimized astrocyte isolation protocol based on magnetic-activated cell sorting via ATPase Na+/K+ transporting subunit beta 2 and profiled the transcriptomic landscape of striatal and cortical astrocytes in transgenic MSA mice. The gene expression profile of astrocytes in the motor cortex displayed an anti-inflammatory signature with increased oligodendroglial and pro-myelinogenic expression pattern. In contrast, striatal astrocytes were defined by elevated pro-inflammatory transcripts accompanied by dysregulated genes involved in homeostatic functions for lipid and calcium metabolism. These findings provide new insights into a region-dependent, dichotomous astrocytic response-potentially beneficial in the cortex and harmful in the striatum-in MSA suggesting a differential role of astrocytes in MSA-related neurodegenerative processes.
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Affiliation(s)
- Y Schneider
- Department of Molecular Neurology, University Hospital Erlangen, Friedrich-Alexander-University Erlangen-Nürnberg, Schwabachanlage 6, 91054, Erlangen, Germany
| | - C Gauer
- Department of Molecular Neurology, University Hospital Erlangen, Friedrich-Alexander-University Erlangen-Nürnberg, Schwabachanlage 6, 91054, Erlangen, Germany
| | - M Andert
- Department of Molecular Neurology, University Hospital Erlangen, Friedrich-Alexander-University Erlangen-Nürnberg, Schwabachanlage 6, 91054, Erlangen, Germany
| | - A Hoffmann
- Department of Molecular Neurology, University Hospital Erlangen, Friedrich-Alexander-University Erlangen-Nürnberg, Schwabachanlage 6, 91054, Erlangen, Germany
- UK Dementia Research Institute, The University of Edinburgh, Edinburgh, UK
- Keenan Research Centre for Biomedical Science, St Michael's Hospital, Toronto, ON, Canada
- Department of Immunology, The University of Toronto, Toronto, ON, Canada
| | - M J Riemenschneider
- Department of Neuropathology, Regensburg University Hospital, 93053, Regensburg, Germany
| | - W Krebs
- Core Unit Bioinformatics, Data Integration and Analysis (CUBiDA), University Hospital Erlangen, Friedrich-Alexander-Universität Erlangen-Nürnberg, 91054, Erlangen, Germany
| | - N Chalmers
- Institute of Biochemistry, Friedrich-Alexander-University Erlangen-Nürnberg, 91054, Erlangen, Germany
| | - C Lötzsch
- Institute of Biochemistry, Friedrich-Alexander-University Erlangen-Nürnberg, 91054, Erlangen, Germany
| | - U J Naumann
- Department of Neurology, University Hospital Erlangen, Friedrich-Alexander-University Erlangen-Nürnberg, 91054, Erlangen, Germany
| | - W Xiang
- Department of Molecular Neurology, University Hospital Erlangen, Friedrich-Alexander-University Erlangen-Nürnberg, Schwabachanlage 6, 91054, Erlangen, Germany
| | - V Rothhammer
- Department of Neurology, University Hospital Erlangen, Friedrich-Alexander-University Erlangen-Nürnberg, 91054, Erlangen, Germany
| | - R Beckervordersandforth
- Institute of Biochemistry, Friedrich-Alexander-University Erlangen-Nürnberg, 91054, Erlangen, Germany
| | - J C M Schlachetzki
- Department of Cellular and Molecular Medicine, University of California-San Diego, La Jolla, CA, 92093, USA
| | - J Winkler
- Department of Molecular Neurology, University Hospital Erlangen, Friedrich-Alexander-University Erlangen-Nürnberg, Schwabachanlage 6, 91054, Erlangen, Germany.
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Westmark S, Hessellund T, Hoffmann A, Madsen BB, Jensen TS, Gielen M, Bøggild H, Leutscher PDC. Increasing use of computed tomography scans in the North Denmark Region raises patient safety concern. Eur J Radiol 2023; 166:110997. [PMID: 37499480 DOI: 10.1016/j.ejrad.2023.110997] [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] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2023] [Revised: 07/04/2023] [Accepted: 07/19/2023] [Indexed: 07/29/2023]
Abstract
PURPOSE Use of computed tomography (CT) scans raises safety concern as lifetime cumulative ionising radiation exposure is associated with risk of developing malignancies. This study aimed to investigate use of abdominal CT scans in the Danish health care sector. METHODS Data on abdominal CT scans performed annually in the North Denmark Region between 2005 and 2018 were extracted from the regional registry with emphasis on patients with a medical history of a repeated abdominal CT scan within 28 days. An audit of the medical files was subsequently conducted in 100 randomly selected patient cases to evaluate clinical information being provided, in addition to justification for a repeated abdominal CT scan, and finally if other radiology modalities could have been applied. RESULTS Number of annually performed abdominal CT scans in this demographically stable regional population increased by a factor 4.3 from 15 in 2005 to 65 in 2018 per 1,000 inhabitants. The audit revealed that 31% of the secondabdominal CT scans within a 28 days period were categorized as either doubtful whether justified or not justified. Moreover, 20% of theCT scans were considered replaceable by ultrasonography. CONCLUSIONS Annual performance of abdominal CT scans increased fourfold during the 14 years period. This tendency is probably attributable to changes in the Danish health care sector by which CT scan examination are used more frequently aiming at more accelerated patient investigation flow in conjunction with shorter length of hospitalization stay. Alertness is strongly warranted towards the associated risk of cancer due to life-time cumulative ionising radiation exposure by this strategy.
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Affiliation(s)
- Signe Westmark
- Centre for Clinical Research, North Denmark Regional Hospital, Hjoerring, Denmark
| | - Thomas Hessellund
- Department of Radiology, Clinic for Diagnostics, North Denmark Regional Hospital, Hjoerring, Denmark
| | - Andreas Hoffmann
- Department of Radiology, Gødstrup Regional Hospital, Gødstrup, Denmark
| | | | - Trine S Jensen
- Centre for Clinical Research, North Denmark Regional Hospital, Hjoerring, Denmark
| | - Mahican Gielen
- Department of Radiology, Clinic for Diagnostics, North Denmark Regional Hospital, Hjoerring, Denmark
| | - Henrik Bøggild
- Public Health and Epidemiology Group, Department of Health Science and Technology, Aalborg University, Aalborg, Denmark; Unit of Clinical Biostatistics, Aalborg University Hospital, Aalborg, Denmark
| | - Peter Derek Christian Leutscher
- Centre for Clinical Research, North Denmark Regional Hospital, Hjoerring, Denmark; Department of Clinical Medicine, Aalborg University, Aalborg, Denmark.
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Ulmer A, Heilrath A, Senfftleben B, O'Connell-Lopez SMO, Kruse B, Seiffert L, Kolatzki K, Langbehn B, Hoffmann A, Baumann TM, Boll R, Chatterley AS, De Fanis A, Erk B, Erukala S, Feinberg AJ, Fennel T, Grychtol P, Hartmann R, Ilchen M, Izquierdo M, Krebs B, Kuster M, Mazza T, Montaño J, Noffz G, Rivas DE, Schlosser D, Seel F, Stapelfeldt H, Strüder L, Tiggesbäumker J, Yousef H, Zabel M, Ziołkowski P, Meyer M, Ovcharenko Y, Vilesov AF, Möller T, Rupp D, Tanyag RMP. Generation of Large Vortex-Free Superfluid Helium Nanodroplets. Phys Rev Lett 2023; 131:076002. [PMID: 37656857 DOI: 10.1103/physrevlett.131.076002] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/14/2023] [Accepted: 06/22/2023] [Indexed: 09/03/2023]
Abstract
Superfluid helium nanodroplets are an ideal environment for the formation of metastable, self-organized dopant nanostructures. However, the presence of vortices often hinders their formation. Here, we demonstrate the generation of vortex-free helium nanodroplets and explore the size range in which they can be produced. From x-ray diffraction images of xenon-doped droplets, we identify that single compact structures, assigned to vortex-free aggregation, prevail up to 10^{8} atoms per droplet. This finding builds the basis for exploring the assembly of far-from-equilibrium nanostructures at low temperatures.
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Affiliation(s)
- Anatoli Ulmer
- Institute of Optics and Atomic Physics, Technische Universität Berlin, Hardenbergstraße 36, 10623 Berlin, Germany
- Department of Physics, Universität Hamburg, Luruper Chaussee 149, 22761 Hamburg, Germany
| | - Andrea Heilrath
- Institute of Optics and Atomic Physics, Technische Universität Berlin, Hardenbergstraße 36, 10623 Berlin, Germany
- Max-Born-Institute for Nonlinear Optics and Short Pulse Spectroscopy, Max-Born-Straße 2A, 12489 Berlin, Germany
| | - Björn Senfftleben
- Max-Born-Institute for Nonlinear Optics and Short Pulse Spectroscopy, Max-Born-Straße 2A, 12489 Berlin, Germany
- European XFEL, Holzkoppel 4, 22869 Schenefeld, Germany
| | - Sean M O O'Connell-Lopez
- Department of Chemistry, University of Southern California, 920 Bloom Walk, Los Angeles, California 90089, USA
| | - Björn Kruse
- Institute for Physics, Universität Rostock, Albert-Einstein-Straße 23, 18059 Rostock, Germany
| | - Lennart Seiffert
- Institute for Physics, Universität Rostock, Albert-Einstein-Straße 23, 18059 Rostock, Germany
| | - Katharina Kolatzki
- Max-Born-Institute for Nonlinear Optics and Short Pulse Spectroscopy, Max-Born-Straße 2A, 12489 Berlin, Germany
- Laboratory for Solid State Physics, Swiss Federal Institute of Technology in Zurich, John-von-Neumann-Weg 9, 8093 Zurich, Switzerland
| | - Bruno Langbehn
- Institute of Optics and Atomic Physics, Technische Universität Berlin, Hardenbergstraße 36, 10623 Berlin, Germany
| | - Andreas Hoffmann
- Max-Born-Institute for Nonlinear Optics and Short Pulse Spectroscopy, Max-Born-Straße 2A, 12489 Berlin, Germany
| | | | - Rebecca Boll
- European XFEL, Holzkoppel 4, 22869 Schenefeld, Germany
| | - Adam S Chatterley
- Department of Chemistry, Aarhus University, Langelandsgade 140, 8000 Aarhus C, Denmark
| | | | - Benjamin Erk
- Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, 22607 Hamburg, Germany
| | - Swetha Erukala
- Department of Chemistry, University of Southern California, 920 Bloom Walk, Los Angeles, California 90089, USA
| | - Alexandra J Feinberg
- Department of Chemistry, University of Southern California, 920 Bloom Walk, Los Angeles, California 90089, USA
| | - Thomas Fennel
- Institute for Physics, Universität Rostock, Albert-Einstein-Straße 23, 18059 Rostock, Germany
| | | | | | - Markus Ilchen
- European XFEL, Holzkoppel 4, 22869 Schenefeld, Germany
- Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, 22607 Hamburg, Germany
| | | | - Bennet Krebs
- Institute for Physics, Universität Rostock, Albert-Einstein-Straße 23, 18059 Rostock, Germany
| | - Markus Kuster
- European XFEL, Holzkoppel 4, 22869 Schenefeld, Germany
| | - Tommaso Mazza
- European XFEL, Holzkoppel 4, 22869 Schenefeld, Germany
| | | | - Georg Noffz
- Institute of Optics and Atomic Physics, Technische Universität Berlin, Hardenbergstraße 36, 10623 Berlin, Germany
| | | | | | - Fabian Seel
- Institute of Optics and Atomic Physics, Technische Universität Berlin, Hardenbergstraße 36, 10623 Berlin, Germany
| | - Henrik Stapelfeldt
- Department of Chemistry, Aarhus University, Langelandsgade 140, 8000 Aarhus C, Denmark
| | | | - Josef Tiggesbäumker
- Institute for Physics, Universität Rostock, Albert-Einstein-Straße 23, 18059 Rostock, Germany
- Department "Life, Light and Matter," Universität Rostock, Albert-Einstein-Straße 23, 18059 Rostock, Germany
| | - Hazem Yousef
- European XFEL, Holzkoppel 4, 22869 Schenefeld, Germany
| | - Michael Zabel
- Institute for Physics, Universität Rostock, Albert-Einstein-Straße 23, 18059 Rostock, Germany
| | | | - Michael Meyer
- European XFEL, Holzkoppel 4, 22869 Schenefeld, Germany
| | | | - Andrey F Vilesov
- Department of Chemistry, University of Southern California, 920 Bloom Walk, Los Angeles, California 90089, USA
- Department of Physics and Astronomy, University of Southern California, 920 Bloom Walk, Los Angeles, California 90089, USA
| | - Thomas Möller
- Institute of Optics and Atomic Physics, Technische Universität Berlin, Hardenbergstraße 36, 10623 Berlin, Germany
| | - Daniela Rupp
- Max-Born-Institute for Nonlinear Optics and Short Pulse Spectroscopy, Max-Born-Straße 2A, 12489 Berlin, Germany
- Laboratory for Solid State Physics, Swiss Federal Institute of Technology in Zurich, John-von-Neumann-Weg 9, 8093 Zurich, Switzerland
| | - Rico Mayro P Tanyag
- Institute of Optics and Atomic Physics, Technische Universität Berlin, Hardenbergstraße 36, 10623 Berlin, Germany
- Department of Chemistry, Aarhus University, Langelandsgade 140, 8000 Aarhus C, Denmark
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Hoffmann A, Franz A, Walther T, Löser C. Utilization of delactosed whey permeate for the synthesis of ethyl acetate with Kluyveromyces marxianus. Appl Microbiol Biotechnol 2023; 107:1635-1648. [PMID: 36786916 PMCID: PMC10006051 DOI: 10.1007/s00253-023-12419-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2022] [Revised: 12/21/2022] [Accepted: 01/30/2023] [Indexed: 02/15/2023]
Abstract
Ethyl acetate is an important organic solvent and currently produced from fossil carbon resources. Microbial synthesis of this ester from sugar-rich waste could be an interesting alternative. Therefore, synthesis of ethyl acetate by Kluyveromyces marxinanus DSM 5422 from delactosed whey permeate (DWP) was studied in an aerated stirred bioreactor at 40 °C. DWP is mainly composed of residual lactose and minerals. The minerals inhibited yeast growth, as witnessed by an increased lag period, a reduced growth rate, and an extended process duration. All experiments were therefore carried out with diluted DWP. In a series of batch experiments, the pH of iron-deficient DWP medium varied between 4.8 and 5.9. The pH of the cultivation medium significantly influenced cell growth and product syntheses, with the highest ethyl acetate yield of 0.347 g g-1 and lowest by-product formation achieved at pH 5.1. It is likely that this effect is due to pH-dependent iron chelation, which affects the iron bioavailability and the intracellular iron content, thus affecting growth and metabolite synthesis. The viability of yeast cells was always high despite the harsh conditions in DWP medium, which enabled extended usage of the biomass in repeated-batch and fed-batch cultivations. These two culture techniques increased the volume of DWP processed per time by 32 and 84% for the repeated-batch and the fed-batch cultivation, respectively, without a drop of the ester yield. KEY POINTS: • Delactosed whey permeate was converted to ethyl acetate with a high rate and yield. • The formation of ethyl acetate in DWP medium at iron limitation is pH-dependent. • Highly active yeasts from batch processes enabled extension as fed and repeated batch.
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Affiliation(s)
- Andreas Hoffmann
- Bioprocess Engineering, Institute of Natural Materials Technology, Technische Universität Dresden, 01062, Dresden, Germany
| | - Alexander Franz
- Bioprocess Engineering, Institute of Natural Materials Technology, Technische Universität Dresden, 01062, Dresden, Germany
- Biophysical Chemistry, Institute of Biochemistry, University of Leipzig, 04103, Leipzig, Germany
| | - Thomas Walther
- Bioprocess Engineering, Institute of Natural Materials Technology, Technische Universität Dresden, 01062, Dresden, Germany
| | - Christian Löser
- Bioprocess Engineering, Institute of Natural Materials Technology, Technische Universität Dresden, 01062, Dresden, Germany.
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8
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Hoffmann A. Risk prediction in theory and practice. Eur J Prev Cardiol 2023; 30:6-7. [PMID: 36125218 DOI: 10.1093/eurjpc/zwac216] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/10/2022] [Revised: 09/15/2022] [Indexed: 01/14/2023]
Affiliation(s)
- Andreas Hoffmann
- University of Basel, Socinstrasse 23, CH 4051 Basel, Switzerland
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9
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Filipova V, Stuerzebecher PE, Kralisch S, Schubert MR, Hoffmann A, Oliveira F, Sheikh B, Blueher M, Kogel A, Scholz M, Miehle K, Ebert T, Laufs U, Toenjes A, Boeckel JN. Leptin mediates protective effects on the vasculature. Eur Heart J 2022. [DOI: 10.1093/eurheartj/ehac544.3057] [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] [Indexed: 11/12/2022] Open
Abstract
Abstract
Introduction and purpose
Lipodystrophy (LD) syndromes are characterized by the loss of adipose tissue resulting in metabolic complications and accelerated atherosclerosis. The systemic concentration of the adipokine leptin is reduced in LD as a result of adipose tissue deficiency. A therapeutical option to treat LD is the substitution of leptin, which improves metabolic complications and reduces mortality. However, the vascular effects of leptin remain largely unknown.
Here we analyze the direct effects of leptin on the vascular system and the development of atherosclerosis.
Methods and results
Treatment of human endothelial cells (ECs) with leptin reduced endothelial inflammation and the process of endothelial-to-mesenchymal transition (EndMT) (CNN1, −41.4%, p<0.05, n=4). In addition, leptin administration prevented the EndMT-induced increase of endothelial permeability. The protective effect of leptin on EndMT was confirmed in vivo in a combined lipodystrophic and atherosclerosis-prone mouse model (LDLR−/−; aP2-nSrebp1c). Treatment of the mice with leptin (3.0 mg/kg body weight daily for 8 weeks) decreased EndMT. Leptin showed no effect on plaques size but reduced the protrusion of plaques in atherosclerotic areas of the aortic roots (−31%, p<0.05, n=4–6).
Cytokine screening revealed an increase of the growth differentiation factor 15 (GDF15) in serum of LD patients (+26.2%, p<0.05, n=53–58) and in ECs after EndMT (+138%, p<0.05, n=6743–10920). This increase was reversed using leptin treatment in ECs undergoing EndMT, in the LD mice model, and in LD patients after 4 weeks of leptin administration. Indeed, treatment of endothelial cells with GDF15 induced EndMT (CNN1, +7.7-fold-control, p<0.05, n=3), and impaired EC barrier function. Neutralizing antibodies targeting GDF15 inhibited EndMT-mediated expression of mesenchymal genes (CNN1, −54%, p<0.05, n=4). The treatment of ECs with serum from LD patients induced EndMT and the increase of mesenchymal marker expression was inhibited with additional administration with neutralizing antibodies targeting GDF15 (CNN1, −28%, p<0.05, n=3).
Conclusion
Our findings indicate that EndMT is part of the cardiovascular disease progression in lipodystrophy syndromes. Leptin treatment has direct protective vascular effects by preventing inflammation, EndMT, and maintaining endothelial integrity.
Funding Acknowledgement
Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Funded by the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation)
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Affiliation(s)
- V Filipova
- University Hospital Leipzig , Leipzig , Germany
| | | | - S Kralisch
- University of Leipzig Medical Center , Leipzig , Germany
| | | | - A Hoffmann
- University Hospital Wuerzburg , Wuerzburg , Germany
| | - F Oliveira
- University of Leipzig and University Hospital Leipzig, Helmholtz Institute for Metabolic, Obesity and Vascular Research of the Helmholtz Zentrum Munich , Leipzig , Germany
| | - B Sheikh
- University of Leipzig and University Hospital Leipzig, Helmholtz Institute for Metabolic, Obesity and Vascular Research of the Helmholtz Zentrum Munich , Leipzig , Germany
| | - M Blueher
- University of Leipzig Medical Center , Leipzig , Germany
| | - A Kogel
- University Hospital Leipzig , Leipzig , Germany
| | - M Scholz
- University of Leipzig , Leipzig , Germany
| | - K Miehle
- University of Leipzig Medical Center , Leipzig , Germany
| | - T Ebert
- University of Leipzig Medical Center , Leipzig , Germany
| | - U Laufs
- University Hospital Leipzig , Leipzig , Germany
| | - A Toenjes
- University of Leipzig Medical Center , Leipzig , Germany
| | - J N Boeckel
- University Hospital Leipzig , Leipzig , Germany
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10
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Hoffmann A, Tin A, Vickers A, Shahrokni A. Preoperative Frailty vs. Impaired Sensorium, Which One Matters the Most for Postoperative Delirium (POD)? J Geriatr Oncol 2022. [DOI: 10.1016/s1879-4068(22)00364-2] [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: 11/05/2022]
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11
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Hoffmann A, Spiegel S, Burger D, Klemens J, Scharfer P, Schabel W. About the slot die coating process of lithium‐ion battery electrodes with regard to an optimized layer structure and edge quality. CHEM-ING-TECH 2022. [DOI: 10.1002/cite.202255273] [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: 11/09/2022]
Affiliation(s)
- A. Hoffmann
- Karlsruhe Institute of Technology Thin Film Technology Straße am Forum 7 76131 Karlsruhe Germany
| | - S. Spiegel
- Karlsruhe Institute of Technology Thin Film Technology Straße am Forum 7 76131 Karlsruhe Germany
| | - D. Burger
- Karlsruhe Institute of Technology Thin Film Technology Straße am Forum 7 76131 Karlsruhe Germany
| | - J. Klemens
- Karlsruhe Institute of Technology Thin Film Technology Straße am Forum 7 76131 Karlsruhe Germany
| | - P. Scharfer
- Karlsruhe Institute of Technology Thin Film Technology Straße am Forum 7 76131 Karlsruhe Germany
| | - W. Schabel
- Karlsruhe Institute of Technology Thin Film Technology Straße am Forum 7 76131 Karlsruhe Germany
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12
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Burger D, Hoffmann A, Klemens J, Scharfer P, Schabel W. Optimizing the production of Li‐ion batteries: Efficient drying of electrodes and savings by multilayer approach. CHEM-ING-TECH 2022. [DOI: 10.1002/cite.202255278] [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: 11/05/2022]
Affiliation(s)
- D. Burger
- Karlsruhe Institute of Technology (KIT) Thin Film Technology (TFT) Straße am Forum 7 76131 Karlsruhe Germany
| | - A. Hoffmann
- Karlsruhe Institute of Technology (KIT) Thin Film Technology (TFT) Straße am Forum 7 76131 Karlsruhe Germany
| | - J. Klemens
- Karlsruhe Institute of Technology (KIT) Thin Film Technology (TFT) Straße am Forum 7 76131 Karlsruhe Germany
| | - P. Scharfer
- Karlsruhe Institute of Technology (KIT) Thin Film Technology (TFT) Straße am Forum 7 76131 Karlsruhe Germany
| | - W. Schabel
- Karlsruhe Institute of Technology (KIT) Thin Film Technology (TFT) Straße am Forum 7 76131 Karlsruhe Germany
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13
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Rose A, Rodriguez-Aguilera J, Schicht G, Lohrenz A, Tvardovskiy A, Büscher J, Hoffmann A, Damm G, Laufs U, Seehofer D, Blüher M, Sheikh B. The impact of cholesterol lowering drugs on metabolism and epigenetics. Atherosclerosis 2022. [DOI: 10.1016/j.atherosclerosis.2022.06.746] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
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14
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Hoffmann A, Rohrbach F, Uhl M, Ceblin M, Bauer T, Mallah M, Jacob T, Heuermann H, Kuehne AJC. Atmospheric pressure
plasma‐jet
treatment of polyacrylonitrile
‐nonwovens
—Stabilization and
roll‐to‐roll
processing. J Appl Polym Sci 2022. [DOI: 10.1002/app.52887] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Andreas Hoffmann
- Institute of Organic and Macromolecular Chemistry, Ulm University Ulm Germany
| | - Felix Rohrbach
- Institute for Microwave and Plasma Technology, FH Aachen ‐ University of Applied Sciences Aachen Germany
- Fricke & Mallah Microwave Technology GmbH Peine Germany
| | - Matthias Uhl
- Institute of Electrochemistry, Ulm University Ulm Germany
| | | | - Thomas Bauer
- DIENES Apparatebau GmbH Mühlheim am Main Germany
| | - Marcel Mallah
- Fricke & Mallah Microwave Technology GmbH Peine Germany
| | - Timo Jacob
- Institute of Electrochemistry, Ulm University Ulm Germany
| | - Holger Heuermann
- Institute for Microwave and Plasma Technology, FH Aachen ‐ University of Applied Sciences Aachen Germany
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15
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Hoffmann A, De Prins M, Sree SP, Vanbutsele G, Smet S, Chandran CV, Radhakrishnan S, Breynaert E, Martens JA. Selective catalytic reduction of NO x with ammonia (NH 3-SCR) over copper loaded LEV type zeolites synthesized with different templates. Phys Chem Chem Phys 2022; 24:15428-15438. [PMID: 35708199 DOI: 10.1039/d2cp01512a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
LEV type zeolites were synthesized with four different structure-directing agents and converted to copper loaded NH3-SCR catalysts. The synthesis recipe was found to impact the respective Al population in the two topologically different framework sites in double and single 6-rings, resolvable by 27Al MAS NMR spectroscopy. Hydrothermal stability was found to be related to the silanol concentration, Si/Al ratio, particle size, crystal morphology, crystal defects, external surface area, and microporosity. Catalytic activity in NH3-SCR was dependent on preferential Al siting in the double 6-rings. Levinite synthesized using adamantylamine showed the strongest preference for Al atoms sitting in double 6-ring sites, and showed the highest catalytic turnover frequency. Unfortunately, because of the large crystal size, copper loading of this sample was limited to 0.6 wt% while other samples could be loaded with copper up to 3.3 wt%. An optimum combination of hydrothermal stability and catalytic activity was obtained with N,N'-bis-dimethylpentanediyldiammonium dibromide as structure-directing agent.
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Affiliation(s)
- Andreas Hoffmann
- Center for Surface Chemistry and Catalysis: Characterization and Application Team, KU Leuven, Celestijnenlaan 200F, Box 2461, 3001 Heverlee, Leuven, Belgium.
| | - Michiel De Prins
- Center for Surface Chemistry and Catalysis: Characterization and Application Team, KU Leuven, Celestijnenlaan 200F, Box 2461, 3001 Heverlee, Leuven, Belgium.
| | - Sreeprasanth Pulinthanathu Sree
- Center for Surface Chemistry and Catalysis: Characterization and Application Team, KU Leuven, Celestijnenlaan 200F, Box 2461, 3001 Heverlee, Leuven, Belgium.
| | - Gina Vanbutsele
- Center for Surface Chemistry and Catalysis: Characterization and Application Team, KU Leuven, Celestijnenlaan 200F, Box 2461, 3001 Heverlee, Leuven, Belgium.
| | - Sam Smet
- Center for Surface Chemistry and Catalysis: Characterization and Application Team, KU Leuven, Celestijnenlaan 200F, Box 2461, 3001 Heverlee, Leuven, Belgium.
| | - C Vinod Chandran
- Center for Surface Chemistry and Catalysis: Characterization and Application Team, KU Leuven, Celestijnenlaan 200F, Box 2461, 3001 Heverlee, Leuven, Belgium.
| | - Sambhu Radhakrishnan
- Center for Surface Chemistry and Catalysis: Characterization and Application Team, KU Leuven, Celestijnenlaan 200F, Box 2461, 3001 Heverlee, Leuven, Belgium.
| | - Eric Breynaert
- Center for Surface Chemistry and Catalysis: Characterization and Application Team, KU Leuven, Celestijnenlaan 200F, Box 2461, 3001 Heverlee, Leuven, Belgium.
| | - Johan A Martens
- Center for Surface Chemistry and Catalysis: Characterization and Application Team, KU Leuven, Celestijnenlaan 200F, Box 2461, 3001 Heverlee, Leuven, Belgium.
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16
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Potreck A, Weyland CS, Seker F, Neuberger U, Herweh C, Hoffmann A, Nagel S, Bendszus M, Mutke MA. Correction to: Accuracy and Prognostic Role of NCCT-ASPECTS Depend on Time from Acute Stroke Symptom-onset for both Human and Machine-learning Based Evaluation. Clin Neuroradiol 2022; 32:585. [PMID: 35389098 PMCID: PMC9187542 DOI: 10.1007/s00062-022-01158-x] [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] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Affiliation(s)
- A Potreck
- Department of Neuroradiology, Heidelberg University Hospital, Heidelberg, Germany
| | - C S Weyland
- Department of Neuroradiology, Heidelberg University Hospital, Heidelberg, Germany
| | - F Seker
- Department of Neuroradiology, Heidelberg University Hospital, Heidelberg, Germany
| | - U Neuberger
- Department of Neuroradiology, Heidelberg University Hospital, Heidelberg, Germany
| | - C Herweh
- Department of Neuroradiology, Heidelberg University Hospital, Heidelberg, Germany
| | - A Hoffmann
- Department of Neuroradiology, Heidelberg University Hospital, Heidelberg, Germany.,Institute of Diagnostic and Interventional Neuroradiology, Inselspital Bern University Hospital, Bern, Switzerland
| | - S Nagel
- Department of Neurology, Heidelberg University Hospital, Heidelberg, Germany
| | - M Bendszus
- Department of Neuroradiology, Heidelberg University Hospital, Heidelberg, Germany
| | - M A Mutke
- Department of Neuroradiology, Heidelberg University Hospital, Heidelberg, Germany.
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17
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Hoffmann A, Jiménez‐Calvo P, Bansmann J, Strauss V, Kuehne AJC. On‐Chip Direct Laser Writing of PAN‐Based Carbon Supercapacitor Electrodes. Macromol Rapid Commun 2022. [DOI: 10.1002/marc.202270019] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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18
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Hoffmann A, Jiménez-Calvo P, Bansmann J, Strauss V, Kuehne AJC. On-chip Direct Laser Writing of PAN-based Carbon Supercapacitor Electrodes. Macromol Rapid Commun 2022; 43:e2100731. [PMID: 35064608 DOI: 10.1002/marc.202100731] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2021] [Revised: 01/19/2022] [Indexed: 11/07/2022]
Abstract
We report carbonization of polyacrylonitrile by direct laser writing to produce microsupercapacitors directly on-chip. We demonstrate the process by producing interdigitated carbon finger electrodes directly on a printed circuit board, which we then employ to characterize our supercapacitor electrodes. By varying the laser power, we are able to tune the process from carbonization to material ablation. This allows to not only convert pristine polyacrylonitrile films into carbon electrodes, but also to pattern and cut away non-carbonized material to produce completely freestanding carbon electrodes. While the carbon electrodes adhere well to the printed circuit board, non-carbonized polyacrylonitrile is peeled off the substrate. We achieve specific capacities as high as 260 μF/cm2 in a supercapacitor with 16 fingers. This article is protected by copyright. All rights reserved.
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Affiliation(s)
- Andreas Hoffmann
- Institute of Organic and Macromolecular Chemistry, Ulm University, Albert-Einstein-Allee 11, Ulm, 89081, Germany
| | - Pablo Jiménez-Calvo
- Department of Colloid Chemistry, Max-Planck-Institute of Colloids and Interfaces, Am Mühlenberg 1, Potsdam, 14476, Germany
| | - Joachim Bansmann
- Institute of Surface Chemistry and Catalysis, Ulm University, Albert-Einstein-Allee 47, Ulm, 89069, Germany
| | - Volker Strauss
- Department of Colloid Chemistry, Max-Planck-Institute of Colloids and Interfaces, Am Mühlenberg 1, Potsdam, 14476, Germany
| | - Alexander J C Kuehne
- Institute of Organic and Macromolecular Chemistry, Ulm University, Albert-Einstein-Allee 11, Ulm, 89081, Germany
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19
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Hoffmann A. Humans are not meant to live alone. Eur J Prev Cardiol 2022; 28:e14. [PMID: 33611535 DOI: 10.1177/2047487320920757] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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20
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Tarras Madsen D, Ciucani U, Hoffmann A, Pantleon W. Thermal stability of thin rolled potassium-doped tungsten sheets during annealing at temperatures up to 1400 °C. Nuclear Materials and Energy 2022. [DOI: 10.1016/j.nme.2022.101126] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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21
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Kell A, Link M, Breyer M, Hoffmann A, Köhl M, Gao K. A compact and fast magnetic coil for the manipulation of quantum gases with Feshbach resonances. Rev Sci Instrum 2021; 92:093202. [PMID: 34598519 DOI: 10.1063/5.0049518] [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: 03/05/2021] [Accepted: 08/27/2021] [Indexed: 06/13/2023]
Abstract
Cold atom experiments commonly use broad magnetic Feshbach resonances to manipulate the interaction between atoms. In order to induce quantum dynamics by a change in the interaction strength, rapid (∼μs) magnetic field changes over several tens of Gauss are required. Here, we present a compact design of a coil and its control circuit for a change in the magnetic field up to 36 G in 3 µs. The setup comprises two concentric solenoids with minimal space requirements, which can be readily added to existing apparatuses. This design makes the observation of non-equilibrium physics with broad Feshbach resonances accessible.
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Affiliation(s)
- A Kell
- Physikalisches Institut, University of Bonn, Wegelerstrasse 8, 53115 Bonn, Germany
| | - M Link
- Physikalisches Institut, University of Bonn, Wegelerstrasse 8, 53115 Bonn, Germany
| | - M Breyer
- Physikalisches Institut, University of Bonn, Wegelerstrasse 8, 53115 Bonn, Germany
| | - A Hoffmann
- Physikalisches Institut, University of Bonn, Wegelerstrasse 8, 53115 Bonn, Germany
| | - M Köhl
- Physikalisches Institut, University of Bonn, Wegelerstrasse 8, 53115 Bonn, Germany
| | - K Gao
- Physikalisches Institut, University of Bonn, Wegelerstrasse 8, 53115 Bonn, Germany
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22
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Bolsi A, Hoffmann A. SP-0581 Patterns of practice and guideline development: A status update from the EPTN image guidance working group. Radiother Oncol 2021. [DOI: 10.1016/s0167-8140(21)08632-1] [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: 11/16/2022]
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23
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Windisch R, Soliman S, Hoffmann A, Chen-Wichmann L, Lutz S, Kellner C, Redondo-Monte E, Vosberg S, Hartmann L, Schneider S, Beier F, Strobl C, Weigert O, Schuendeln M, Bernhagen J, Humpe A, Brendel C, Klump H, Greif P, Wichmann C. Converting a leukemic transcription factor into a powerful tool for large-scale ex vivo production of human phagocytes. Cytotherapy 2021. [DOI: 10.1016/s1465324921003844] [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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Schultheiss K, Sato N, Matthies P, Körber L, Wagner K, Hula T, Gladii O, Pearson JE, Hoffmann A, Helm M, Fassbender J, Schultheiss H. Time Refraction of Spin Waves. Phys Rev Lett 2021; 126:137201. [PMID: 33861132 DOI: 10.1103/physrevlett.126.137201] [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: 09/09/2020] [Accepted: 03/04/2021] [Indexed: 06/12/2023]
Abstract
We present an experimental study of time refraction of spin waves (SWs) propagating in microscopic waveguides under the influence of time-varying magnetic fields. Using space- and time-resolved Brillouin light scattering microscopy, we demonstrate that the broken translational symmetry along the time coordinate results in a loss of energy conservation for SWs and thus allows for a broadband and controllable shift of the SW frequency. With an integrated design of SW waveguide and microscopic current line for the generation of strong, nanosecond-long, magnetic field pulses, a conversion efficiency up to 39% of the carrier SW frequency is achieved, significantly larger compared to photonic systems. Given the strength of the magnetic field pulses and its strong impact on the SW dispersion relation, the effect of time refraction can be quantified on a length scale comparable to the SW wavelength. Furthermore, we utilize time refraction to excite SW bursts with pulse durations in the nanosecond range and a frequency shift depending on the pulse polarity.
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Affiliation(s)
- K Schultheiss
- Helmholtz-Zentrum Dresden - Rossendorf, Institute of Ion Beam Physics and Materials Research, 01328 Dresden, Germany
| | - N Sato
- Helmholtz-Zentrum Dresden - Rossendorf, Institute of Ion Beam Physics and Materials Research, 01328 Dresden, Germany
| | - P Matthies
- Helmholtz-Zentrum Dresden - Rossendorf, Institute of Ion Beam Physics and Materials Research, 01328 Dresden, Germany
- Fakultät Physik, Technische Universität Dresden, 01062 Dresden, Germany
| | - L Körber
- Helmholtz-Zentrum Dresden - Rossendorf, Institute of Ion Beam Physics and Materials Research, 01328 Dresden, Germany
- Fakultät Physik, Technische Universität Dresden, 01062 Dresden, Germany
| | - K Wagner
- Helmholtz-Zentrum Dresden - Rossendorf, Institute of Ion Beam Physics and Materials Research, 01328 Dresden, Germany
| | - T Hula
- Helmholtz-Zentrum Dresden - Rossendorf, Institute of Ion Beam Physics and Materials Research, 01328 Dresden, Germany
| | - O Gladii
- Helmholtz-Zentrum Dresden - Rossendorf, Institute of Ion Beam Physics and Materials Research, 01328 Dresden, Germany
| | - J E Pearson
- Materials Science Division, Argonne National Laboratory, Argonne, Illinois 60439, USA
| | - A Hoffmann
- Materials Science Division, Argonne National Laboratory, Argonne, Illinois 60439, USA
| | - M Helm
- Helmholtz-Zentrum Dresden - Rossendorf, Institute of Ion Beam Physics and Materials Research, 01328 Dresden, Germany
- Fakultät Physik, Technische Universität Dresden, 01062 Dresden, Germany
| | - J Fassbender
- Helmholtz-Zentrum Dresden - Rossendorf, Institute of Ion Beam Physics and Materials Research, 01328 Dresden, Germany
- Fakultät Physik, Technische Universität Dresden, 01062 Dresden, Germany
| | - H Schultheiss
- Helmholtz-Zentrum Dresden - Rossendorf, Institute of Ion Beam Physics and Materials Research, 01328 Dresden, Germany
- Fakultät Physik, Technische Universität Dresden, 01062 Dresden, Germany
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25
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Löser C, Kupsch C, Walther T, Hoffmann A. A new approach for balancing the microbial synthesis of ethyl acetate and other volatile metabolites during aerobic bioreactor cultivations. Eng Life Sci 2021; 21:137-153. [PMID: 33716613 PMCID: PMC7923609 DOI: 10.1002/elsc.202000047] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2020] [Accepted: 10/23/2020] [Indexed: 01/05/2023] Open
Abstract
Ethyl acetate is an organic solvent with many industrial applications, currently produced by energy-intensive chemical processes based on fossil carbon resources. Ethyl acetate can be synthesized from renewable sugars by yeasts like Kluyveromyces marxianus in aerobic processes. However, ethyl acetate is highly volatile and thus stripped from aerated cultivation systems which complicate the quantification of the produced ester. Synthesis of volatile metabolites is commonly monitored by repeated analysis of metabolite concentrations in both the gas and liquid phase. In this study, a model-based method for quantifying the synthesis and degradation of volatile metabolites was developed. This quantification of volatiles is solely based on repeatedly measured gas-phase concentrations and allows calculation of reaction rates and yields in high temporal resolution. Parameters required for these calculations were determined in abiotic stripping tests. The developed method was validated for ethyl acetate, ethanol and acetaldehyde which were synthesized by K. marxianus DSM 5422 during an iron-limited batch cultivation; it was shown that the presented method is more precise and less time-consuming than the conventional method. The biomass-specific synthesis rate and the yield of ethyl acetate varied over time and exhibited distinct momentary maxima of 0.50 g g‒1h‒1 and 0.38 g g‒1 at moderate iron limitation.
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Affiliation(s)
- Christian Löser
- Chair of Bioprocess Engineering, Institute of Natural Materials TechnologyTechnische Universität DresdenDresdenGermany
| | - Christian Kupsch
- Chair of Bioprocess Engineering, Institute of Natural Materials TechnologyTechnische Universität DresdenDresdenGermany
| | - Thomas Walther
- Chair of Bioprocess Engineering, Institute of Natural Materials TechnologyTechnische Universität DresdenDresdenGermany
| | - Andreas Hoffmann
- Chair of Bioprocess Engineering, Institute of Natural Materials TechnologyTechnische Universität DresdenDresdenGermany
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26
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Hoffmann A, Kupsch C, Walther T, Löser C. Synthesis of ethyl acetate from glucose by Kluyveromyces marxianus, Cyberlindnera jadinii and Wickerhamomyces anomalus depending on the induction mode. Eng Life Sci 2021; 21:154-168. [PMID: 33716614 PMCID: PMC7923572 DOI: 10.1002/elsc.202000048] [Citation(s) in RCA: 3] [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] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2020] [Revised: 10/28/2020] [Accepted: 11/12/2020] [Indexed: 11/17/2022] Open
Abstract
Ethyl acetate is currently produced from fossil carbon resources. This ester could also be microbially synthesized from sugar-rich wastes of the food industry. Wild-type strains with GRAS status are preferred for such applications. Production of ethyl acetate by wild-type yeasts has been repeatedly reported, but comparative studies with several strains at various induction modes are largely missing. Here, synthesis of ethyl acetate by three yeasts with GRAS status, Kluyveromyces marxianus DSM 5422, Cyberlindnera jadinii DSM 2361 and Wickerhamomyces anomalus DSM 6766, was studied under identical and well-defined conditions in an aerated bioreactor, by inducing the ester synthesis via iron or oxygen limitation. Balancing the ester synthesis was based on measured concentrations of ethyl acetate in the exhaust gas, delivering masses of synthesized ester and synthesis rates in a high temporal resolution. All tested yeasts synthesized ethyl acetate under these conditions, but the intensity varied with the strain and induction mode. The highest yields were achieved under iron limitation with K. marxianus (0.182 g g-1) and under oxygen limitation with W. anomalus (0.053 g g-1). Iron limitation proved to be the better inducer for ester synthesis while oxygen limitation favored ethanol formation. K. marxianus DSM 5422 was the most potent producer of ethyl acetate exhibiting the highest biomass-specific synthesis rate of 0.5 g g-1h-1 under moderate iron limitation.
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Affiliation(s)
- Andreas Hoffmann
- Chair of Bioprocess EngineeringInstitute of Natural Materials TechnologyTechnische Universität DresdenDresdenGermany
| | - Christian Kupsch
- Chair of Bioprocess EngineeringInstitute of Natural Materials TechnologyTechnische Universität DresdenDresdenGermany
| | - Thomas Walther
- Chair of Bioprocess EngineeringInstitute of Natural Materials TechnologyTechnische Universität DresdenDresdenGermany
| | - Christian Löser
- Chair of Bioprocess EngineeringInstitute of Natural Materials TechnologyTechnische Universität DresdenDresdenGermany
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27
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Affiliation(s)
- Andreas Hoffmann
- Department of Cardiology, University of Basel, Socinstrasse 23, 4051 Basel, Switzerland
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28
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Bang W, Silvani R, Hoffmann A, Ketterson JB, Montoncello F, Jungfleisch MB. Ferromagnetic resonance in single vertices and 2D lattices macro-dipoles of elongated nanoelements: measurements and simulations. J Phys Condens Matter 2021; 33:065803. [PMID: 33091893 DOI: 10.1088/1361-648x/abc402] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
We report broadband ferromagnetic resonance measurements of the in-plane magnetic field response of three- and four-fold symmetric vertices formed by non-contacting permalloy nano-ellipses together with extended lattices constructed from them. Complementing the experimental data with simulations, we are able to show that, as far as the most intense FMR responses are concerned, the spectra of vertices and lattices can largely be interpreted in terms of a superposition of the underlying hysteretic responses of the individual ellipses, as elemental building blocks of the system. This property suggest that it is possible to understand the orientation of the individual magnetic dipole moments in a dipole network in terms of dynamic measurements alone, thereby offering a powerful tool to analyze the alignment statistics in frustrated systems that are exposed to various magnetic histories.
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Affiliation(s)
- Wonbae Bang
- Department of Physics and Astronomy, Northwestern University, Evanston, IL 60208, United States of America
- Materials Science Division, Argonne National Laboratory, Argonne, IL 60439, United States of America
| | - R Silvani
- Dipartimento di Fisica e Geologia, Università di Perugia, Perugia, I-06123, Italy
- Istituto Nazionale di Ricerca Metrologica, Torino, I-10135, Italy
| | - A Hoffmann
- Materials Science Division, Argonne National Laboratory, Argonne, IL 60439, United States of America
- Department of Materials Science and Engineering, University of Illinois at Urbana-Champaign, Urbana, IL 61801, United States of America
| | - J B Ketterson
- Department of Physics and Astronomy, Northwestern University, Evanston, IL 60208, United States of America
- Department of Electrical and Computer Engineering, Northwestern University, Evanston, IL 60208, United States of America
| | - F Montoncello
- Dipartimento di Fisica e Scienze della Terra, Università di Ferrara, Ferrara, I-44121, Italy
| | - M B Jungfleisch
- Department of Physics and Astronomy, University of Delaware, Newark, DE 19716, United States of America
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Hoffmann A, Cardoso AS, Fonseca NVB, Romanzini EP, Siniscalchi D, Berndt A, Ruggieri AC, Reis RA. Effects of supplementation with corn distillers' dried grains on animal performance, nitrogen balance, and enteric CH 4 emissions of young Nellore bulls fed a high-tropical forage diet. Animal 2021; 15:100155. [PMID: 33573951 DOI: 10.1016/j.animal.2020.100155] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [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: 03/26/2020] [Revised: 11/16/2020] [Accepted: 11/17/2020] [Indexed: 11/27/2022] Open
Abstract
The inclusion of corn-dried distillers' grains (DDG) could be an alternative supplement to increase animal performance, nitrogen efficiency usage (NEU), and decrease enteric methane (CH4) emissions. Our goal was to determine whether DDG could replace a traditional supplement (cottonseed meal) without affecting animal performance, N balance, and CH4 emissions. The experiment was conducted during the forage growing season (December to April), with 15 d adaptation, and a 112 d experimental period. The experimental design was completely randomized with four treatments: a mineral supplement (MS), cottonseed meal supplement (CS), 50% replacement of CS by DDG (50DDG), and 100% replacement of CS by DDG (100DDG). Cottonseed meal and DDG were used as protein supplement. A total of 12 paddocks, 3 per treatment, were used to measure forage mass: morphological and chemical composition of forage, forage allowance, and animal performance. Six animals per treatment were used to evaluate DM intake, digestibility, CH4 emissions, microbial protein production (MCP), and NEU of each treatment. Eighty-one Young Nellore bulls (48 testers, 12 per treatments and 33 adjusters) with initial BW of 255 ± 5 kg (10-12 months old) were supplemented with each supplement type at a level of 0.3% of BW. Pasture management was continuous stocking with a variable stocking rate (put-and-take). Enteric CH4 was measured using the gas tracer technique. The MCP was quantified using purine derivatives and the NEU mass balance. No differences were found in nutrient intake (P > 0.228). Individual animal performance and gain per area were higher in the treatments with concentrates compared with that of MS; however, there was no difference among treatments CS, 50DDG, and 100DDG. The ADG was 0.83 for MS and 1.08 kg/animal/d when supplemented (P < 0.05). Gain per hectare was 709 kg/ha for MS and 915 kg/ha when supplemented with concentrates (P < 0.05). There was no difference in CH4 production among treatments that average 180 g/animal/d; however, CH4 per kg of gain was reduced with CS. The CH4 conversion factor averaged 5.91%. There was no difference in the synthesis of MCP and NEU. Corn DDG can replace 100% of cottonseed meal as a protein source for supplementation of young Nellore bulls grazing in tropical pastures without affecting animal performance, NEU, MCP, and CH4 emissions.
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Affiliation(s)
- A Hoffmann
- Department of Animal Science, São Paulo State University - Unesp, Jaboticabal, São Paulo, Brazil; Trouw Nutrition, Campinas, São Paulo, Brazil
| | - A S Cardoso
- Department of Animal Science, São Paulo State University - Unesp, Jaboticabal, São Paulo, Brazil.
| | - N V B Fonseca
- Department of Animal Science, São Paulo State University - Unesp, Jaboticabal, São Paulo, Brazil
| | - E P Romanzini
- Department of Animal Science, São Paulo State University - Unesp, Jaboticabal, São Paulo, Brazil
| | - D Siniscalchi
- Department of Animal Science, São Paulo State University - Unesp, Jaboticabal, São Paulo, Brazil
| | - A Berndt
- Embrapa Pecuária Sudeste, São Carlos, São Paulo, Brazil
| | - A C Ruggieri
- Department of Animal Science, São Paulo State University - Unesp, Jaboticabal, São Paulo, Brazil
| | - R A Reis
- Department of Animal Science, São Paulo State University - Unesp, Jaboticabal, São Paulo, Brazil
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Kretschmar M, Tuemmler J, Schütte B, Hoffmann A, Senfftleben B, Mero M, Sauppe M, Rupp D, Vrakking MJJ, Will I, Nagy T. Thin-disk laser-pumped OPCPA system delivering 4.4 TW few-cycle pulses. Opt Express 2020; 28:34574-34585. [PMID: 33182922 DOI: 10.1364/oe.404077] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/29/2020] [Accepted: 10/07/2020] [Indexed: 06/11/2023]
Abstract
We present an optical parametric chirped pulse amplification (OPCPA) system delivering 4.4 TW pulses centered at 810 nm with a sub-9 fs duration and a carrier-envelope phase stability of 350 mrad. The OPCPA setup pumped by sub-10 ps pulses from two Yb:YAG thin-disk lasers at 100 Hz repetition rate is optimized for a high conversion-efficiency. The terawatt pulses of the OPCPA are utilized for generating intense extreme ultraviolet (XUV) pulses by high-order harmonic generation, achieving XUV pulse energies approaching the microjoule level.
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31
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Schellhammer S, Gantz S, Karsch L, Van der Kraaij E, Smeets J, Serra A, Pawelke J, Hoffmann A. OC-0679: On-line MRI-based proton beam range verification: first experimental proof-of-concept. Radiother Oncol 2020. [DOI: 10.1016/s0167-8140(21)00701-5] [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: 11/15/2022]
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32
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De Prins M, Verheyen E, Hoffmann A, Vanbutsele G, Sree SP, Kerkhofs S, Van Tendeloo L, Schütze FW, Martens J. Structural parameters governing low temperature activity of small pore copper zeolites in NH3-SCR. J Catal 2020. [DOI: 10.1016/j.jcat.2020.08.003] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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33
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Zeng FL, Ren ZY, Li Y, Zeng JY, Jia MW, Miao J, Hoffmann A, Zhang W, Wu YZ, Yuan Z. Intrinsic Mechanism for Anisotropic Magnetoresistance and Experimental Confirmation in Co_{x}Fe_{1-x} Single-Crystal Films. Phys Rev Lett 2020; 125:097201. [PMID: 32915598 DOI: 10.1103/physrevlett.125.097201] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/18/2020] [Revised: 07/13/2020] [Accepted: 07/31/2020] [Indexed: 06/11/2023]
Abstract
Using first-principles transport calculations, we predict that the anisotropic magnetoresistance (AMR) of single-crystal Co_{x}Fe_{1-x} alloys is strongly dependent on the current orientation and alloy concentration. An intrinsic mechanism for AMR is found to arise from the band crossing due to magnetization-dependent symmetry protection. These special k points can be shifted towards or away from the Fermi energy by varying the alloy composition and hence the exchange splitting, thus allowing AMR tunability. The prediction is confirmed by delicate transport measurements, which further reveal a reciprocal relationship of the longitudinal and transverse resistivities along different crystal axes.
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Affiliation(s)
- F L Zeng
- Department of Physics, State Key Laboratory of Surface Physics, Fudan University, Shanghai 200433, China
| | - Z Y Ren
- School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing 100083, China
- Center for Advanced Quantum Studies and Department of Physics, Beijing Normal University, Beijing 100875, China
| | - Y Li
- Department of Physics, Oakland University, Rochester, Michigan 48309, USA
- Materials Science Division, Argonne National Laboratory, Lemont, Illinois 60439, USA
| | - J Y Zeng
- Department of Physics, State Key Laboratory of Surface Physics, Fudan University, Shanghai 200433, China
| | - M W Jia
- Department of Physics, State Key Laboratory of Surface Physics, Fudan University, Shanghai 200433, China
| | - J Miao
- School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing 100083, China
| | - A Hoffmann
- Materials Science Division, Argonne National Laboratory, Lemont, Illinois 60439, USA
| | - W Zhang
- Department of Physics, Oakland University, Rochester, Michigan 48309, USA
- Materials Science Division, Argonne National Laboratory, Lemont, Illinois 60439, USA
| | - Y Z Wu
- Department of Physics, State Key Laboratory of Surface Physics, Fudan University, Shanghai 200433, China
- Shanghai Research Center for Quantum Sciences, Shanghai 201315, China
| | - Z Yuan
- Center for Advanced Quantum Studies and Department of Physics, Beijing Normal University, Beijing 100875, China
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34
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Banti C, Kourkoumelis N, Hatzidimitriou A, Antoniadou I, Dimou A, Rallis M, Hoffmann A, Schmidtke M, McGuire K, Busath D, Kolocouris A, Hadjikakou S. Amantadine copper(II) chloride conjugate with possible implementation in influenza virus inhibition. Polyhedron 2020. [DOI: 10.1016/j.poly.2020.114590] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
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35
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Fehrmann A, Franz M, Hoffmann A, Rudzik L, Wüst E. Dairy Product Analysis: Identification of Microorganisms by Mid-Infrared Spectroscopy and Determination of Constituents by Raman Spectroscopy. J AOAC Int 2020. [DOI: 10.1093/jaoac/78.6.1537] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
Abstract
Identification of microorganisms by traditional microbiological methods is time consuming. The German Federal Health Office has developed a method using mid-infrared spectroscopy to identify microorganisms rapidly. This method has been modified for application to microorganisms important in the dairy industry. Mid- and near-infrared spectroscopies are well-established methods for quantitative measurements of fat, protein, lactose, and solid content in a variety of products. A disadvantage of both methods is the huge absorption due to water; extraction of other components is complicated and can be achived only statistically. With Raman spectroscopy, water causes less absorption. We investigated the use of Raman spectroscopy as a quantitative method for milk powder.
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Affiliation(s)
- Angela Fehrmann
- Milchwirtschaftliche Lehr- und Untersuchungsanstalt und Fachhochschule Hannover Heisterbergallee 12, 30453 Hanover, Germany
| | - Monika Franz
- Milchwirtschaftliche Lehr- und Untersuchungsanstalt und Fachhochschule Hannover Heisterbergallee 12, 30453 Hanover, Germany
| | - Andreas Hoffmann
- Milchwirtschaftliche Lehr- und Untersuchungsanstalt und Fachhochschule Hannover Heisterbergallee 12, 30453 Hanover, Germany
| | - Lutz Rudzik
- Milchwirtschaftliche Lehr- und Untersuchungsanstalt und Fachhochschule Hannover Heisterbergallee 12, 30453 Hanover, Germany
| | - Eberhard Wüst
- Milchwirtschaftliche Lehr- und Untersuchungsanstalt und Fachhochschule Hannover Heisterbergallee 12, 30453 Hanover, Germany
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Wieczorek J, Cichon M, Wieczorek P, Hoffmann A, Wnuk-Wojnar A, Szydlo K, Lasek-Bal A, Mizia-Stec K. P1816 Cerebral microembolism in low-risk patients with paroxysmal atrial fibrillation before and after pulmonary vein isolationCerebral microembolism in low-risk patients with paroxysmal atrial fibrillation. Eur Heart J Cardiovasc Imaging 2020. [DOI: 10.1093/ehjci/jez319.1164] [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] [Indexed: 11/13/2022] Open
Abstract
Abstract
BACKGROUND
Invasive treatment of atrial fibrillation (AF) becomes more suitable and effective therapy. There are no consistent data describing the occurrence of potential neurological complications in low-risk patients with paroxysmal AF.
AIM
to determine the occurrence, consequences and risk factors for brain white matter hiperintensities (WMH) assessed in magnetic resonance imaging (MRI) in low-risk patients before and after pulmonary vein isolation (PVI) treatment.
METHODS
Eighty patients with symptomatic paroxysmal AF (median age: 58 years (IQR 50-63), K/M: 30/50), CHA2DS2-Vasc ≤ 3 (CHA2DS2-Vasc: 2 (IQR 1-2.5)) were included in the study. Before and after a minimum of 6-month period after PVI-RF treatment (med. 9,9 months, IQR 7.6-11.8 months) a clinical evaluation with brain MRI and Mini Mental State Examination (MMSE) test were determined. Severity of brain WMH in MRI was assessed in the Fazekas scale (pic 1). The efficacy of PVI-RF treatment analyzed in a 7-day Holter monitoring was confirmed in 43 (53.8%) patients.
RESULTS
Baseline WMH lesions were found in 55 (68.8%) patients. Patients with baseline WMH lesion obtained similar results in the MMSE test, compared to patients with a normal brain image in the MRI study. There was a statistically significant more frequent occurrence of cerebral WMH lesions among older patients, with a higher CHA2DS2-Vasc score, with left atrial (LA) dilatation and dysfunction. Factors affecting the severity of the WMH were: the co-occurrence of the patent foramen ovale (PFO) and coronary artery disease (CAD).
After PVI-RF treatment there were no significant changes in the presence and severity of WMH lesions. Similarly, there were no significant changes in the cognitive abilities assessed with MMSE test compared to the pre-procedural evaluation. There were also similar factors predisposing to brain WMH changes: older age, higher CHA2DS2-Vasc score and higher BMI. In turn, the degree of the brain WMH severity after observation period was dependent on age, higher CHA2DS2-Vasc score, presence of PFO and CAD and the initial LA function.
CONCLUSIONS Cerebral microembolism assessed in MRI is often found in low-risk patients with paroxysmal AF, and its presence and severity are associated with LA dilatation and dysfunction, age and higher CHA2DS2-Vasc score. Additional factors affecting the severity of WMH lesions are: the co-occurrence of PFO and CAD. PVI-RF procedure and its efficacy does not influence on MRI lesions. In the population of relatively young AF patients with no significant cardiovascular disease burden, cerebral microembolism is not related to cognitive impairment.
Abstract P1816 Figure. pic 1
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Affiliation(s)
- J Wieczorek
- Medical University of Silesia, 1st Department of Cardiology, Katowice, Poland
| | - M Cichon
- Medical University of Silesia, 1st Department of Cardiology, Katowice, Poland
| | - P Wieczorek
- Medical University of Silesia, 1st Department of Cardiology, Katowice, Poland
| | - A Hoffmann
- Medical University of Silesia, 1st Department of Cardiology, Katowice, Poland
| | - A Wnuk-Wojnar
- Medical University of Silesia, 1st Department of Cardiology, Katowice, Poland
| | - K Szydlo
- Medical University of Silesia, 1st Department of Cardiology, Katowice, Poland
| | - A Lasek-Bal
- 7th Public Hospital of the Silesian Medical University, Department of Neurology, Katowice, Poland
| | - K Mizia-Stec
- Medical University of Silesia, 1st Department of Cardiology, Katowice, Poland
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37
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Robbat A, Hoffmann A, Namara KM, Huang Y. Quantitative Identification of Pesticides as Target Compounds and Unknowns by Spectral Deconvolution of Gas Chromatographic/Mass Spectrometric Data. J AOAC Int 2019. [DOI: 10.1093/jaoac/91.6.1467] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [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]
Abstract
Abstract
The results of gas chromatography/mass spectrometry (MS), with Ion Signature Technology, Inc. (North Smithfield, RI) quantitative deconvolution software, are discussed for pesticides identified both as target compounds by using retention and MS data and as unknowns by using only mass spectra. Target compound analysis of 32 pesticides, surrogates, and an internal standard added to lemon oil over a wide concentration range produced precision and accuracy that are well within the acceptable criteria of 25 and 50 for complex samples. When 112 pesticides were added to orange oil and searched as unknowns, 110 of the 112 compounds were correctly identified, with an average pesticide recovery of 101 19. The injection volume of the orange oil fortified with pesticides was selected so that 4 ng per compound was injected on column. No false negatives were found, because ion signals for the 2 unidentified pesticides were not acquired by the instrument in either the standard mixture or the oil. No false positives were detected, although >750 widely different compounds were included in the library search.
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Affiliation(s)
- Albert Robbat
- Tufts University, Chemistry Department, 62 Talbot Ave, Medford, MA 02155
| | - Andreas Hoffmann
- Gerstel GmbH & Co. KG, Eberhard-Gerstel-Platz 1, D-45473 Mlheim an der Ruhr, Germany
| | - Kevin Mac Namara
- Irish Distillers-Pernod Ricard, Midleton Distillery, Midleton, Cork, Ireland
| | - Yongli Huang
- Tufts University, Chemistry Department, 62 Talbot Ave, Medford, MA 02155
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Raschka C, Hoffmann A, Andre J. Doping-Epidemiologie in Fitnessstudios im Großraum Würzburg. Rechtsmedizin (Berl) 2019. [DOI: 10.1007/s00194-019-00348-1] [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: 10/26/2022]
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39
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Tello K, Hoffmann A, Beutel B, Greulich T, Vogelmeier CF, Richter MJ, Kuhnert S, Böselt T, Alter P, Holland A, Idzko M, Buhl R, Koczulla AR. Anti-interleukin-5 therapy (mepolizumab) in life-threatening asthma attack: A case-based discussion. Respir Med Case Rep 2019; 28:100927. [PMID: 31485410 PMCID: PMC6715903 DOI: 10.1016/j.rmcr.2019.100927] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2019] [Revised: 08/14/2019] [Accepted: 08/21/2019] [Indexed: 02/03/2023] Open
Abstract
We report about a case of a compassionate off-label use of the anti-interleukin-5-agent mepolizumab in a ventilated patient with life-threatening asthma attack in eosinophilic asthma. The patient suffered from severe eosinophilic asthma and was transmitted to our hospital with an asthma attack and a life-threatening respiratory state under ventilation. Since high dose steroids had not yielded a sufficient respiratory improvement mepolizumab was administered subcutaneously. After administration of mepolizumab respiratory state and ventilation parameter improved significantly. Two days after administration the patient was weaned could be extubated 8 days later and recovered completely from the asthma attack. The presented clinical case is suggestive of future clinical trials or registry studies to evaluate potential clinical benefits of anti-interleukin-5 treatment in patients with severe exacerbations of eosinophilic asthma.
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Affiliation(s)
- Khodr Tello
- Department of Medicine, Pulmonary and Critical Care Medicine, University Medical Center Giessen and Marburg, Philipps-University Marburg, Germany.,Member of the German Center for Lung Research (DZL), Germany.,Department of Internal Medicine, Justus Liebig University Giessen, Universities of Giessen and Marburg Lung Center (UGMLC), Germany
| | - Andreas Hoffmann
- Schoen Klinik Berchtesgadener Land, Department of Pneumology, Member of the German Center for Lung Research (DZL), Schoenau am Königssee, Germany
| | - Björn Beutel
- Department of Medicine, Pulmonary and Critical Care Medicine, University Medical Center Giessen and Marburg, Philipps-University Marburg, Germany.,Member of the German Center for Lung Research (DZL), Germany
| | - Timm Greulich
- Department of Medicine, Pulmonary and Critical Care Medicine, University Medical Center Giessen and Marburg, Philipps-University Marburg, Germany.,Member of the German Center for Lung Research (DZL), Germany
| | - Claus Franz Vogelmeier
- Department of Medicine, Pulmonary and Critical Care Medicine, University Medical Center Giessen and Marburg, Philipps-University Marburg, Germany.,Member of the German Center for Lung Research (DZL), Germany
| | - Manuel Jonas Richter
- Department of Internal Medicine, Justus Liebig University Giessen, Universities of Giessen and Marburg Lung Center (UGMLC), Germany
| | - Stefan Kuhnert
- Department of Internal Medicine, Justus Liebig University Giessen, Universities of Giessen and Marburg Lung Center (UGMLC), Germany
| | - Tobias Böselt
- Department of Medicine, Pulmonary and Critical Care Medicine, University Medical Center Giessen and Marburg, Philipps-University Marburg, Germany.,Member of the German Center for Lung Research (DZL), Germany
| | - Peter Alter
- Department of Medicine, Pulmonary and Critical Care Medicine, University Medical Center Giessen and Marburg, Philipps-University Marburg, Germany.,Member of the German Center for Lung Research (DZL), Germany
| | - Angelique Holland
- Department of Medicine, Pulmonary and Critical Care Medicine, University Medical Center Giessen and Marburg, Philipps-University Marburg, Germany.,Member of the German Center for Lung Research (DZL), Germany
| | - Marco Idzko
- Department of Pneumology, University Hospital Freiburg, Freiburg, Germany
| | - Roland Buhl
- Pulmonary Department, Mainz University Hospital, Mainz, Germany
| | - Andreas Rembert Koczulla
- Department of Medicine, Pulmonary and Critical Care Medicine, University Medical Center Giessen and Marburg, Philipps-University Marburg, Germany.,Member of the German Center for Lung Research (DZL), Germany.,Schoen Klinik Berchtesgadener Land, Department of Pneumology, Member of the German Center for Lung Research (DZL), Schoenau am Königssee, Germany
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Hoffmann A. Run for your health!…or lift weight? Eur J Prev Cardiol 2019; 26:1645-1646. [PMID: 31180757 DOI: 10.1177/2047487319857835] [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] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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41
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Jung B, Iacono P, Hahn M, Borsch M, Hoffmann A, Nickolaus P. P275 Both BI 443651 and BI 1265162 demonstrate inhibition of the liquid absorption from the rat airway epithelium in vivo. J Cyst Fibros 2019. [DOI: 10.1016/s1569-1993(19)30568-5] [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: 10/26/2022]
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42
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Gantz S, Riemann L, Smeets J, Pawelke J, Hoffmann A. PO-1021 Influence of beamline and scanning magnets on the magnetic fringe field at a proton PBS nozzle. Radiother Oncol 2019. [DOI: 10.1016/s0167-8140(19)31441-0] [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: 11/16/2022]
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43
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Thiele J, Schneider S, Valentini C, Lohaus F, Sarah S, Haak D, Krause M, Hoffmann A, Troost E. PO-1094 Use of an individual abdominal corset in patients with upper-GI tumors treated with proton therapy. Radiother Oncol 2019. [DOI: 10.1016/s0167-8140(19)31514-2] [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: 10/26/2022]
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44
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Hoffmann A. SP-0460 Integration of MR and particle therapy – how far are we? Radiother Oncol 2019. [DOI: 10.1016/s0167-8140(19)30880-1] [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: 11/29/2022]
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45
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Schneider S, Dolde K, Alimusay M, Fluegel B, Saito N, Hoffmann A, Pfaffenberger A. EP-1971 Comparison of pancreatic respiratory motion using three abdominal corsets for particle therapy. Radiother Oncol 2019. [DOI: 10.1016/s0167-8140(19)32391-6] [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: 10/26/2022]
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46
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Tönjes A, Kralisch S, Hoffmann A, Schleinitz D, Kratzsch J, Blüher M, Stumvoll M, Kovacs P, Fasshauer M, Ebert T. Circulating Pro-Neurotensin in gestational diabetes mellitus. Nutr Metab Cardiovasc Dis 2019; 29:23-29. [PMID: 30527352 DOI: 10.1016/j.numecd.2018.09.011] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/05/2018] [Revised: 09/21/2018] [Accepted: 09/24/2018] [Indexed: 11/24/2022]
Abstract
BACKGROUND AND AIMS Pro-Neurotensin (NT), a stable surrogate parameter of NT, has recently been introduced as a peptide predicting the development of obesity, diabetes mellitus, cardiovascular diseases, and cardiovascular mortality. However, regulation of Pro-NT in gestational diabetes mellitus (GDM) remains uninvestigated. METHODS AND RESULTS Pro-NT was quantified in 74 women with GDM, 74 healthy, gestational age-matched, pregnant controls, as well as in a second cohort comprising of 74 healthy, non-pregnant control women, using a chemiluminometric sandwich immunoassay. Pro-NT was correlated to measures of obesity, hypertension, glucose and lipid metabolism, renal function, and inflammation. Mean ± standard deviation of circulating Pro-NT levels were not significantly different in women with GDM (100.2 ± 75.7 pmol/l) as compared to healthy, pregnant controls (103.2 ± 37.4 pmol/l) and healthy, non-pregnant female controls (105.9 ± 38.9 pmol/l) (p = 0.661). Homeostasis model assessment of insulin resistance (HOMA-IR) and creatinine positively correlated with serum Pro-NT in multivariate regression analysis. In contrast, free fatty acids (FFA) were inversely correlated with circulating Pro-NT. Results sustained adjustment for pregnancy status. CONCLUSIONS Circulating Pro-NT is not independently associated with GDM, but is with HOMA-IR, creatinine, and FFA even after adjustment for pregnancy status.
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Affiliation(s)
- A Tönjes
- University of Leipzig, Department of Endocrinology and Nephrology, 04103, Leipzig, Germany
| | - S Kralisch
- University of Leipzig, Department of Endocrinology and Nephrology, 04103, Leipzig, Germany; Leipzig University Medical Center, IFB AdiposityDiseases, 04103, Leipzig, Germany
| | - A Hoffmann
- University of Leipzig, Department of Endocrinology and Nephrology, 04103, Leipzig, Germany
| | - D Schleinitz
- Leipzig University Medical Center, IFB AdiposityDiseases, 04103, Leipzig, Germany
| | - J Kratzsch
- University of Leipzig, Institute of Laboratory Medicine, 04103, Leipzig, Germany
| | - M Blüher
- University of Leipzig, Department of Endocrinology and Nephrology, 04103, Leipzig, Germany
| | - M Stumvoll
- University of Leipzig, Department of Endocrinology and Nephrology, 04103, Leipzig, Germany
| | - P Kovacs
- Leipzig University Medical Center, IFB AdiposityDiseases, 04103, Leipzig, Germany
| | - M Fasshauer
- University of Leipzig, Department of Endocrinology and Nephrology, 04103, Leipzig, Germany; Leipzig University Medical Center, IFB AdiposityDiseases, 04103, Leipzig, Germany; Justus-Liebig-University, Institute of Nutritional Science, 35390, Giessen, Germany
| | - T Ebert
- University of Leipzig, Department of Endocrinology and Nephrology, 04103, Leipzig, Germany; Leipzig University Medical Center, IFB AdiposityDiseases, 04103, Leipzig, Germany.
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47
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Kaux JF, Janssen L, Drion P, Nusgens B, Libertiaux V, Pascon F, Heyeres A, Hoffmann A, Lambert C, Le Goff C, Denoël V, Defraigne JO, Rickert M, Crielaard JM, Colige A. Vascular Endothelial Growth Factor-111 (VEGF-111) and tendon healing: preliminary results in a rat model of tendon injury. Muscles Ligaments Tendons J 2019. [DOI: 10.32098/mltj.01.2014.05] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Affiliation(s)
- J.-F. Kaux
- Physical Medicine Service, Department of Motility Sciences, University and University Hospital of Liège, Belgium
| | - L. Janssen
- Culture and Therapy Unit, Assistance Publique des Hôpitaux de Marseille, France
| | - P. Drion
- Culture and Therapy Unit, Assistance Publique des Hôpitaux de Marseille, France
| | - B. Nusgens
- Laboratory of Connective Tissues Biology, GIGA-R, University of Liège, Belgium
| | | | - F. Pascon
- Department ARGENCO, University of Liège, Belgium
| | - A. Heyeres
- Laboratory of Connective Tissues Biology, GIGA-R, University of Liège, Belgium
| | - A. Hoffmann
- Laboratory of Connective Tissues Biology, GIGA-R, University of Liège, Belgium
| | - C. Lambert
- Laboratory of Connective Tissues Biology, GIGA-R, University of Liège, Belgium
| | - C. Le Goff
- Department of Clinical Biology, University and University Hospital of Liège, Belgium
| | - V. Denoël
- Department ARGENCO, University of Liège, Belgium
| | - J.-O. Defraigne
- CREDEC, Laboratory of Experimental Surgery, University of Liège, Belgium
| | - M. Rickert
- Department of Orthopaedic Surgery, University of Giessen, Germany
| | - J.-M. Crielaard
- Physical Medicine Service, Department of Motility Sciences, University and University Hospital of Liège, Belgium
| | - A. Colige
- Animal Facility of University Hospital of Liège, ULg-GIGA-R, University of Liège, Belgium
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48
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Renesto D, Araújo T, Hoffmann A, Maneck Delevatti L, Ferrari A, Leite R, Rincão G, Reis R. PSXIII-15 Substitution of protein source by corn DDGS in the supplementation of Nellore young bulls during the rearing phase. J Anim Sci 2018. [DOI: 10.1093/jas/sky404.950] [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: 11/13/2022] Open
Affiliation(s)
- D Renesto
- Sao Paulo State University,Jaboticabal, Brazil
| | - T Araújo
- Sao Paulo State University,Jaboticabal, Brazil
| | - A Hoffmann
- Sao Paulo State University,Jaboticabal, Brazil
| | | | - A Ferrari
- Sao Paulo State University,Jaboticabal, Brazil
| | - R Leite
- Sao Paulo State University,Jaboticabal, Brazil
| | - G Rincão
- Sao Paulo State University,Jaboticabal, Brazil
| | - R Reis
- Sao Paulo State University,Jaboticabal, Brazil
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49
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Hoffmann A, Haas C, Hennig S, Ostermann K, Bley T, Löser C, Walther T. Modeling population dynamics in a microbial consortium under control of a synthetic pheromone-mediated communication system. Eng Life Sci 2018; 19:400-411. [PMID: 32625018 DOI: 10.1002/elsc.201800107] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [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: 06/23/2018] [Revised: 10/10/2018] [Accepted: 10/24/2018] [Indexed: 11/06/2022] Open
Abstract
Microbial consortia can be used to catalyze complex biotransformations. Tools to control the behavior of these consortia in a technical environment are currently lacking. In the present study, a synthetic biology approach was used to build a model consortium of two Saccharomyces cerevisiae strains where growth and expression of the fluorescent marker protein EGFP by the receiver strain is controlled by the concentration of α-factor pheromone, which is produced by the emitter strain. We have developed a quantitative experimental and theoretical framework to describe population dynamics in the model consortium. We measured biomass growth and metabolite production in controlled bioreactor experiments, and used flow cytometry to monitor changes of the subpopulations and protein expression under different cultivation conditions. This dataset was used to parameterize a segregated mathematical model, which took into account fundamental growth processes, pheromone-induced growth arrest and EGFP production, as well as pheromone desensitization after extended exposure. The model was able to predict the growth dynamics of single-strain cultures and the consortium quantitatively and provides a basis for using this approach in actual biotransformations.
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Affiliation(s)
- Andreas Hoffmann
- Institute of Natural Materials Technology Technische Universität Dresden Dresden Germany
| | - Christiane Haas
- Institute of Natural Materials Technology Technische Universität Dresden Dresden Germany
| | - Stefan Hennig
- Institute of Genetics Technische Universität Dresden Dresden Germany
| | - Kai Ostermann
- Institute of Genetics Technische Universität Dresden Dresden Germany
| | - Thomas Bley
- Institute of Natural Materials Technology Technische Universität Dresden Dresden Germany
| | - Christian Löser
- Institute of Natural Materials Technology Technische Universität Dresden Dresden Germany
| | - Thomas Walther
- Institute of Natural Materials Technology Technische Universität Dresden Dresden Germany
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50
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Jayakumar N, Sollapur R, Hoffmann A, Grigorova T, Hartung A, Schwuchow A, Bierlich J, Kobelke J, Schmidt MA, Spielmann C. Polarization evolution in single-ring antiresonant hollow-core fibers. Appl Opt 2018; 57:8529-8535. [PMID: 30461919 DOI: 10.1364/ao.57.008529] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/10/2018] [Accepted: 09/01/2018] [Indexed: 06/09/2023]
Abstract
Understanding polarization in waveguides is of fundamental importance for any photonic device and is particularly relevant within the scope of fiber optics. Here, we investigate the dependence of the geometry-induced polarization behavior of single-ring antiresonant hollow-core fibers on various parameters from the experimental perspective, showing that structural deviations from an ideal polygonal shape impose birefringence and polarization-dependent loss, confirmed by a toy model. The minimal output ellipticity was found at the wavelength of lowest loss near the center of the transmission band, whereas birefringence substantially increases toward the resonances. The analysis that qualitatively also applies to other kinds of hollow-core fibers showed that maximizing the amount of linearly polarized light at the fiber output demands both operating at the wavelength of lowest loss, as well as carefully choosing the relative orientation of input polarization. This should correspond to the situation in which the difference of the core extent along the two corresponding orthogonal polarization directions is minimal. Due to their practical relevance, we expect our findings to be very important in fields such as nonlinear photonics or metrology.
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