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Paschke K, Diestelkamp S, Zapf A, Busch K, Arnaud N, Prehn-Kristensen A, Reis O, Stark M, Cloes JO, Schulz AL, Brauer H, Krömer T, Thomasius R. An app-based training for adolescents with problematic digital-media use and their parents (Res@t digital): protocol for a cluster-randomized clinical trial. Front Psychiatry 2024; 14:1245536. [PMID: 38328520 PMCID: PMC10847547 DOI: 10.3389/fpsyt.2023.1245536] [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] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/23/2023] [Accepted: 12/29/2023] [Indexed: 02/09/2024] Open
Abstract
Background Digital media-use disorders (DMUD) in adolescents are a rising phenomenon associated with psychological distress, comorbid mental disorders, and high burden on affected families. Since the ICD-11 introduced criteria for gaming disorder, these can now be transferred to describe additional DMUD associated with social media platforms and streaming services. Most evidence for effective treatments comes from cognitive-behavioral therapy (CBT). However, interventions based on theoretical models for adolescents and their parents are widely missing, leading to a significant clinical gap. Methods Res@t digital (Resource-Strengthening Training for Adolescents with Problematic Digital-Media Use and their Parents) is the app-based translation of the first model-based digital intervention for adolescents with DMUD and their parents based on CBT. It comprises separate but content-related modules for adolescents (Res@t-A) and parents (Res@t-P), applying multimodal techniques. The effectiveness of Res@t will be evaluated within a multicenter cluster-randomized controlled evaluator-blinded pre-post follow-up trial with the waitlist control group (CG). In addition to the Res@t program in the intervention group, both groups will receive treatment as usual within primary child and adolescent psychiatric/psychotherapeutic healthcare. The primary outcome addresses DMUD symptom reduction after 10 weeks. Secondary outcomes are related to a reduction in psychological and family-related problems and an increase in parental self-efficacy. All outcomes will be assessed using standardized self-report measures. A total of 1,334 participating adolescent-parent dyads from a large clinical network throughout Germany are planned to be included in the primary analyses based on an intention-to-treat approach, applying linear mixed models. Discussion Assuming superiority of Res@t over the control condition, the intervention has the potential to provide evidence-based treatment for a significant number of help-seeking families, supporting local healthcare structures and resources. It is a promising program for practicable implementation and flexible use in different settings. Clinical trial registration https://drks.de, DRKS00031043.
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Affiliation(s)
- Kerstin Paschke
- German Center for Addiction Research in Childhood and Adolescence (DZSKJ), University Medical Center Hamburg-Eppendorf (UKE), Hamburg, Germany
| | - Silke Diestelkamp
- German Center for Addiction Research in Childhood and Adolescence (DZSKJ), University Medical Center Hamburg-Eppendorf (UKE), Hamburg, Germany
| | - Antonia Zapf
- Institute of Medical Biometry and Epidemiology (IMBE), University Medical Center Hamburg-Eppendorf (UKE), Hamburg, Germany
| | - Katharina Busch
- German Center for Addiction Research in Childhood and Adolescence (DZSKJ), University Medical Center Hamburg-Eppendorf (UKE), Hamburg, Germany
| | - Nicolas Arnaud
- German Center for Addiction Research in Childhood and Adolescence (DZSKJ), University Medical Center Hamburg-Eppendorf (UKE), Hamburg, Germany
| | - Alexander Prehn-Kristensen
- Institute of Child and Adolescent Psychiatry, Center for Integrative Psychiatry, School of Medicine, Christian-Albrecht University Kiel, Kiel, Germany
| | - Olaf Reis
- Department for Child and Adolescent Psychiatry and Neurology, Rostock University Medical Center, Rostock, Germany
| | - Maria Stark
- Institute of Medical Biometry and Epidemiology (IMBE), University Medical Center Hamburg-Eppendorf (UKE), Hamburg, Germany
| | - Jan-Ole Cloes
- German Center for Addiction Research in Childhood and Adolescence (DZSKJ), University Medical Center Hamburg-Eppendorf (UKE), Hamburg, Germany
| | - Anna-Lena Schulz
- German Center for Addiction Research in Childhood and Adolescence (DZSKJ), University Medical Center Hamburg-Eppendorf (UKE), Hamburg, Germany
| | - Hannah Brauer
- Institute of Child and Adolescent Psychiatry, Center for Integrative Psychiatry, School of Medicine, Christian-Albrecht University Kiel, Kiel, Germany
| | - Thomas Krömer
- Collaborative Practice for Child and Adolescent Psychiatry, Psychotherapy and Psychosomatics, Hamburg, Germany
| | - Rainer Thomasius
- German Center for Addiction Research in Childhood and Adolescence (DZSKJ), University Medical Center Hamburg-Eppendorf (UKE), Hamburg, Germany
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Ruggeri K, Ashcroft-Jones S, Abate Romero Landini G, Al-Zahli N, Alexander N, Andersen MH, Bibilouri K, Busch K, Cafarelli V, Chen J, Doubravová B, Dugué T, Durrani AA, Dutra N, Garcia-Garzon E, Gomes C, Gracheva A, Grilc N, Gürol DM, Heidenry Z, Hu C, Krasner R, Levin R, Li J, Messenger AME, Miralem M, Nilsson F, Oberschulte JM, Obi T, Pan A, Park SY, Pascu DS, Pelica S, Pyrkowski M, Rabanal K, Ranc P, Mekiš Recek Ž, Symeonidou A, Tutuska OS, Vdovic M, Yuan Q, Stock F. The persistence of cognitive biases in financial decisions across economic groups. Sci Rep 2023; 13:10329. [PMID: 37365245 DOI: 10.1038/s41598-023-36339-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2022] [Accepted: 06/01/2023] [Indexed: 06/28/2023] Open
Abstract
While economic inequality continues to rise within countries, efforts to address it have been largely ineffective, particularly those involving behavioral approaches. It is often implied but not tested that choice patterns among low-income individuals may be a factor impeding behavioral interventions aimed at improving upward economic mobility. To test this, we assessed rates of ten cognitive biases across nearly 5000 participants from 27 countries. Our analyses were primarily focused on 1458 individuals that were either low-income adults or individuals who grew up in disadvantaged households but had above-average financial well-being as adults, known as positive deviants. Using discrete and complex models, we find evidence of no differences within or between groups or countries. We therefore conclude that choices impeded by cognitive biases alone cannot explain why some individuals do not experience upward economic mobility. Policies must combine both behavioral and structural interventions to improve financial well-being across populations.
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Affiliation(s)
- Kai Ruggeri
- Department of Health Policy and Management, Columbia University, 722 W 168th Street, New York, NY, 10032, USA
- Centre for Business Research, Judge Business School, University of Cambridge, Cambridge, CB2 1AG, UK
| | | | | | - Narjes Al-Zahli
- Department of Computer Science, Columbia University, 500 W 120th Street, New York, NY, 10027, USA
- Department of Psychology, Columbia University, 1180 Amsterdam Avenue, New York, NY, 10027, USA
| | | | - Mathias Houe Andersen
- Department of Psychology and Behavioural Sciences, Aarhus University, Bartholins Allé 11, 8000, Aarhus, Denmark
| | - Katherine Bibilouri
- Department of Psychology, Columbia University, 1180 Amsterdam Avenue, New York, NY, 10027, USA
| | - Katharina Busch
- German Center for Addiction Research in Childhood and Adolescence, University Medical Center Hamburg-Eppendorf, Martinistr 52, 20246, Hamburg, Germany
| | - Valentina Cafarelli
- Department of Health Policy and Management, Columbia University, 722 W 168th Street, New York, NY, 10032, USA
| | - Jennifer Chen
- Department of Economics, Columbia University, 420 W 118th Street, New York, NY, 10027, USA
| | - Barbora Doubravová
- Department of Psychology, Faculty of Social Studies, Masaryk University, Joštova 218/10, 60200, Brno, Czech Republic
| | - Tatianna Dugué
- Department of Psychology, Columbia University, 1180 Amsterdam Avenue, New York, NY, 10027, USA
| | - Aleena Asfa Durrani
- Department of Health Policy and Management, Columbia University, 722 W 168th Street, New York, NY, 10032, USA
| | - Nicholas Dutra
- Department of Psychology, Columbia University, 1180 Amsterdam Avenue, New York, NY, 10027, USA
| | | | - Christian Gomes
- Department of Psychology, Columbia University, 1180 Amsterdam Avenue, New York, NY, 10027, USA
| | - Aleksandra Gracheva
- Department of Political Science, Columbia University, 420 W 118th Street, New York, NY, 10027, USA
| | - Neža Grilc
- Department of Life Sciences, University of Roehampton, Whitelands College, London, SW15 4JD, UK
| | | | - Zoe Heidenry
- Department of Psychology, Columbia University, 1180 Amsterdam Avenue, New York, NY, 10027, USA
| | - Clara Hu
- Department of Psychology, Columbia University, 1180 Amsterdam Avenue, New York, NY, 10027, USA
| | - Rachel Krasner
- Department of Psychology, Barnard College, Columbia University, 3009 Broadway, New York, NY, 10027, USA
| | - Romy Levin
- Department of Psychology, Barnard College, Columbia University, 3009 Broadway, New York, NY, 10027, USA
| | - Justine Li
- Department of Biological Sciences, Columbia University, 1212 Amsterdam Avenue, New York, NY, 10027, USA
| | | | | | - Fredrik Nilsson
- Department of Clinical Neuroscience, Division of Psychology, Karolinska Institutet, Solna, 171 77, Stockholm, Sweden
| | | | - Takashi Obi
- Department of Public Administration, Columbia University, 420 West 118th Street, New York, NY, 10027, USA
| | - Anastasia Pan
- Department of Psychology, Barnard College, Columbia University, 3009 Broadway, New York, NY, 10027, USA
| | - Sun Young Park
- Department of Psychology, Columbia University, 1180 Amsterdam Avenue, New York, NY, 10027, USA
| | - Daria Stefania Pascu
- Department of Developmental Psychology and Socialisation, University of Padua, Via Venezia 12, 35131, Padua, PD, Italy
| | - Sofia Pelica
- Department of Social and Organizational Psychology, Iscte-University Institute of Lisbon, Avenida das Forças Armadas, 1649-026, Lisbon, Portugal
| | | | - Katherinne Rabanal
- Department of Cognitive Science, Columbia University, 116th & Broadway, New York, NY, 10027, USA
| | - Pika Ranc
- Department of Psychology, University of Ljubljana, Aškerčeva Cesta 2, 1000, Ljubljana, Slovenia
| | - Žiga Mekiš Recek
- Department of Psychology, University of Ljubljana, Aškerčeva Cesta 2, 1000, Ljubljana, Slovenia
| | - Alexandra Symeonidou
- Department of Clinical Psychology, Leiden University, Wassenaarseweg 52, 2333 AK, Leiden, South Holland, The Netherlands
| | - Olivia Symone Tutuska
- Department of Sociology, Columbia University, 606 W 122nd Street, New York, NY, 10027, USA
| | - Milica Vdovic
- Department of Psychology, Faculty of Media and Communications, Singidunum University, Karadjordjeva 65, Belgrade, 11000, Serbia
| | - Qihang Yuan
- Department of Psychology, Columbia University, 1180 Amsterdam Avenue, New York, NY, 10027, USA
| | - Friederike Stock
- University of Cologne, Albertus-Magnus-Platz, 50923, Cologne, Germany
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Kalita A, Zhong Q, Busch K, El-Ganainy R. Quantum-inspired multicore optical fiber. Opt Lett 2022; 47:2526-2529. [PMID: 35561394 DOI: 10.1364/ol.454684] [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: 01/28/2022] [Accepted: 04/19/2022] [Indexed: 06/15/2023]
Abstract
We introduce a new, to the best of our knowledge, type of multicore optical fiber having a quantum-inspired network topology and unique spectral features. Particularly, the connectivity between the cores is generated by unfolding a circular array of coupled quantum oscillators in Fock space. We show that in such a fiber geometry, the eigenvalues of the optical supermodes exhibit partial degeneracy and form a ladder. In turn, this leads to revival dynamics, allowing for a periodic re-imaging of the input intensity. As an example, we present a realistic design with six cores in silica glass platforms.
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Busch K, Kny M, Huang N, Klassert TE, Stock M, Hahn A, Graeger S, Todiras M, Schmidt S, Chamling B, Willenbrock M, Groß S, Biedenweg D, Heuser A, Scheidereit C, Butter C, Felix SB, Otto O, Luft FC, Slevogt H, Fielitz J. Inhibition of the NLRP3/IL-1β axis protects against sepsis-induced cardiomyopathy. J Cachexia Sarcopenia Muscle 2021; 12:1653-1668. [PMID: 34472725 PMCID: PMC8718055 DOI: 10.1002/jcsm.12763] [Citation(s) in RCA: 63] [Impact Index Per Article: 21.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/11/2020] [Revised: 06/03/2021] [Accepted: 07/09/2021] [Indexed: 12/18/2022] Open
Abstract
BACKGROUND Septic cardiomyopathy worsens the prognosis of critically ill patients. Clinical data suggest that interleukin-1β (IL-1β), activated by the NLRP3 inflammasome, compromises cardiac function. Whether or not deleting Nlrp3 would prevent cardiac atrophy and improve diastolic cardiac function in sepsis was unclear. Here, we investigated the role of NLRP3/IL-1β in sepsis-induced cardiomyopathy and cardiac atrophy. METHODS Male Nlrp3 knockout (KO) and wild-type (WT) mice were exposed to polymicrobial sepsis by caecal ligation and puncture (CLP) surgery (KO, n = 27; WT, n = 33) to induce septic cardiomyopathy. Sham-treated mice served as controls (KO, n = 11; WT, n = 16). Heart weights and morphology, echocardiography and analyses of gene and protein expression were used to evaluate septic cardiomyopathy and cardiac atrophy. IL-1β effects on primary and immortalized cardiomyocytes were investigated by morphological and molecular analyses. IonOptix and real-time deformability cytometry (RT-DC) analysis were used to investigate functional and mechanical effects of IL-1β on cardiomyocytes. RESULTS Heart morphology and echocardiography revealed preserved systolic (stroke volume: WT sham vs. WT CLP: 33.1 ± 7.2 μL vs. 24.6 ± 8.7 μL, P < 0.05; KO sham vs. KO CLP: 28.3 ± 8.1 μL vs. 29.9 ± 9.9 μL, n.s.; P < 0.05 vs. WT CLP) and diastolic (peak E wave velocity: WT sham vs. WT CLP: 750 ± 132 vs. 522 ± 200 mm/s, P < 0.001; KO sham vs. KO CLP: 709 ± 152 vs. 639 ± 165 mm/s, n.s.; P < 0.05 vs. WT CLP) cardiac function and attenuated cardiac (heart weight-tibia length ratio: WT CLP vs. WT sham: -26.6%, P < 0.05; KO CLP vs. KO sham: -3.3%, n.s.; P < 0.05 vs. WT CLP) and cardiomyocyte atrophy in KO mice during sepsis. IonOptix measurements showed that IL-1β decreased contractility (cell shortening: IL-1β: -15.4 ± 2.3%, P < 0.001 vs. vehicle, IL-1RA: -6.1 ± 3.3%, P < 0.05 vs. IL-1β) and relaxation of adult rat ventricular cardiomyocytes (time-to-50% relengthening: IL-1β: 2071 ± 225 ms, P < 0.001 vs. vehicle, IL-1RA: 564 ± 247 ms, P < 0.001 vs. IL-1β), which was attenuated by an IL-1 receptor antagonist (IL-1RA). RT-DC analysis indicated that IL-1β reduced cardiomyocyte size (P < 0.001) and deformation (P < 0.05). RNA sequencing showed that genes involved in NF-κB signalling, autophagy and lysosomal protein degradation were enriched in hearts of septic WT but not in septic KO mice. Western blotting and qPCR disclosed that IL-1β activated NF-κB and its target genes, caused atrophy and decreased myosin protein in myocytes, which was accompanied by an increased autophagy gene expression. These effects were attenuated by IL-1RA. CONCLUSIONS IL-1β causes atrophy, impairs contractility and relaxation and decreases deformation of cardiomyocytes. Because NLRP3/IL-1β pathway inhibition attenuates cardiac atrophy and cardiomyopathy in sepsis, it could be useful to prevent septic cardiomyopathy.
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Affiliation(s)
- Katharina Busch
- Experimental and Clinical Research Center (ECRC), Charité-Universitätsmedizin Berlin, Max Delbrück Center (MDC) for Molecular Medicine in the Helmholtz Association, Berlin, Germany
| | - Melanie Kny
- Experimental and Clinical Research Center (ECRC), Charité-Universitätsmedizin Berlin, Max Delbrück Center (MDC) for Molecular Medicine in the Helmholtz Association, Berlin, Germany
| | - Nora Huang
- Experimental and Clinical Research Center (ECRC), Charité-Universitätsmedizin Berlin, Max Delbrück Center (MDC) for Molecular Medicine in the Helmholtz Association, Berlin, Germany.,Department of Cardiology, Heart Center Brandenburg and Medical School Brandenburg (MHB), Bernau, Germany
| | - Tilman E Klassert
- ZIK Septomics, Host Septomics, Jena, Germany.,Jena University Hospital, Integrated Research and Treatment Center - Center for Sepsis Control and Care (CSCC), Jena, Germany
| | - Magdalena Stock
- ZIK Septomics, Host Septomics, Jena, Germany.,Jena University Hospital, Integrated Research and Treatment Center - Center for Sepsis Control and Care (CSCC), Jena, Germany
| | - Alexander Hahn
- Experimental and Clinical Research Center (ECRC), Charité-Universitätsmedizin Berlin, Max Delbrück Center (MDC) for Molecular Medicine in the Helmholtz Association, Berlin, Germany
| | - Sebastian Graeger
- DZHK (German Center for Cardiovascular Research), Partner Site Greifswald, Greifswald, Germany
| | - Mihail Todiras
- Laboratory of Molecular Biology of Peptide Hormones, Max Delbrück Center for Molecular Medicine, Berlin, Germany.,Nicolae Testemiţanu State University of Medicine and Pharmacy, Chișinău, Moldova
| | - Sibylle Schmidt
- Experimental and Clinical Research Center (ECRC), Charité-Universitätsmedizin Berlin, Max Delbrück Center (MDC) for Molecular Medicine in the Helmholtz Association, Berlin, Germany
| | - Bishwas Chamling
- DZHK (German Center for Cardiovascular Research), Partner Site Greifswald, Greifswald, Germany.,Department of Internal Medicine B, Molecular Cardiology, University Medicine Greifswald, Greifswald, Germany
| | - Michael Willenbrock
- Signal Transduction in Development and Cancer, Max Delbrück Center for Molecular Medicine, Berlin, Germany
| | - Stefan Groß
- DZHK (German Center for Cardiovascular Research), Partner Site Greifswald, Greifswald, Germany.,Department of Internal Medicine B, Molecular Cardiology, University Medicine Greifswald, Greifswald, Germany
| | - Doreen Biedenweg
- DZHK (German Center for Cardiovascular Research), Partner Site Greifswald, Greifswald, Germany.,Centre for Innovation Competence - Humoral Immune Response in Cardiovascular Diseases, University of Greifswald, Greifswald, Germany
| | - Arnd Heuser
- Animal Phenotyping Facility, Max Delbrück Center for Molecular Medicine, Berlin, Germany
| | - Claus Scheidereit
- Signal Transduction in Development and Cancer, Max Delbrück Center for Molecular Medicine, Berlin, Germany
| | - Christian Butter
- Department of Cardiology, Heart Center Brandenburg and Medical School Brandenburg (MHB), Bernau, Germany
| | - Stephan B Felix
- DZHK (German Center for Cardiovascular Research), Partner Site Greifswald, Greifswald, Germany.,Department of Internal Medicine B, Molecular Cardiology, University Medicine Greifswald, Greifswald, Germany
| | - Oliver Otto
- DZHK (German Center for Cardiovascular Research), Partner Site Greifswald, Greifswald, Germany.,Centre for Innovation Competence - Humoral Immune Response in Cardiovascular Diseases, University of Greifswald, Greifswald, Germany
| | - Friedrich C Luft
- Experimental and Clinical Research Center (ECRC), Charité-Universitätsmedizin Berlin, Max Delbrück Center (MDC) for Molecular Medicine in the Helmholtz Association, Berlin, Germany
| | - Hortense Slevogt
- ZIK Septomics, Host Septomics, Jena, Germany.,Jena University Hospital, Integrated Research and Treatment Center - Center for Sepsis Control and Care (CSCC), Jena, Germany
| | - Jens Fielitz
- Experimental and Clinical Research Center (ECRC), Charité-Universitätsmedizin Berlin, Max Delbrück Center (MDC) for Molecular Medicine in the Helmholtz Association, Berlin, Germany.,DZHK (German Center for Cardiovascular Research), Partner Site Greifswald, Greifswald, Germany.,Department of Internal Medicine B, Molecular Cardiology, University Medicine Greifswald, Greifswald, Germany
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Busch K, Andersen A, Petersen J, Petersen S, Rønde H, Bentzen L, Pilskog S, Skyt P, Nørrevang O, Muren L. PO-1551 Towards range-guidance in proton therapy to detect organ motion induced dose degradations. Radiother Oncol 2021. [DOI: 10.1016/s0167-8140(21)08002-6] [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: 11/15/2022]
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Busch K, Andersen A, Petersen J, Skyt P, Nørrevang O, Muren L. PO-1461: Benchmarking proton therapy water equivalent path length calculations against TPS algorithms. Radiother Oncol 2020. [DOI: 10.1016/s0167-8140(21)01479-1] [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: 10/22/2022]
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Reiche D, Busch K, Intravaia F. Nonadditive Enhancement of Nonequilibrium Atom-Surface Interactions. Phys Rev Lett 2020; 124:193603. [PMID: 32469548 DOI: 10.1103/physrevlett.124.193603] [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: 10/18/2019] [Accepted: 04/06/2020] [Indexed: 06/11/2023]
Abstract
The motion-induced drag force acting on a particle moving parallel to an arrangement of N objects is analyzed. Particular focus is placed on the nonequilibrium statistics of the interaction and on the interplay between the system's geometry and the different dissipative processes occurring in realistic setups. We show that the drag force can exhibit a markedly nonadditive enhancement with respect to the corresponding additive approximation. The specific case of a planar cavity-a relevant configuration for many experiments-is calculated, showing an enhancement of about one order of magnitude. This and similar configurations are of significant potential interest for future measurements that aim to detect the drag force.
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Affiliation(s)
- D Reiche
- Humboldt-Universität zu Berlin, Institut für Physik, AG Theoretische Optik & Photonik, 12489 Berlin, Germany
- Max-Born-Institut, 12489 Berlin, Germany
| | - K Busch
- Humboldt-Universität zu Berlin, Institut für Physik, AG Theoretische Optik & Photonik, 12489 Berlin, Germany
- Max-Born-Institut, 12489 Berlin, Germany
| | - F Intravaia
- Humboldt-Universität zu Berlin, Institut für Physik, AG Theoretische Optik & Photonik, 12489 Berlin, Germany
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Abstract
An atom moving in a vacuum at constant velocity and parallel to a surface experiences a frictional force induced by the dissipative interaction with the quantum fluctuations of the electromagnetic field. We show that the combination of nonequilibrium dynamics, the anomalous Doppler effect, and spin-momentum locking of light mediates an intriguing interplay between the atom's translational and rotational motion. In turn, this deeply affects the drag force in a way that is reminiscent of classical rolling friction. Our fully non-Markovian and nonequilibrium description reveals counterintuitive features characterizing the atom's velocity-dependent rotational dynamics. These results prompt interesting directions for tuning the interaction and for investigating nonequilibrium dynamics as well as the properties of confined light.
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Affiliation(s)
- F Intravaia
- Humboldt-Universität zu Berlin, Institut für Physik, AG Theoretische Optik & Photonik, 12489 Berlin, Germany
| | | | - D Reiche
- Max-Born-Institut, 12489 Berlin, Germany
| | - D A R Dalvit
- Theoretical Division, MS B213, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
| | - K Busch
- Humboldt-Universität zu Berlin, Institut für Physik, AG Theoretische Optik & Photonik, 12489 Berlin, Germany
- Max-Born-Institut, 12489 Berlin, Germany
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Busch K, Wehner A, Dorsch R, Hartmann K, Unterer S. Akuter blutiger Durchfall als Vorstellungsgrund bei einem Hund mit primärem Hypoadrenokortizismus. Tierarztl Prax Ausg K 2018. [DOI: 10.1055/s-0038-1623781] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Abstract
ZusammenfassungEin 7 Jahre alter, männlich-kastrierter Schäferhundmischling wurde wegen akuten blutigen Erbrechens und wässrig-blutigen Durchfalls vorgestellt. Aufgrund klinischer Präsentation, unspezifischer Laborwertveränderungen, unauffälliger Elektrolytwerte und schneller klinischer Besserung auf Infusionstherapie wurde die Diagnose “hämorrhagische Gastroenteritis” (HGE) gestellt. Bei erneuter Vorstellung des Hundes wegen Leistungsschwäche einen Monat später bestanden Elektrolytverschiebungen (Hyperkaliämie und Hyponatriämie), die charakteristisch für einen typischen Hypoadrenokortizismus sind. Mittels ACTH-Stimulationstest wurde eine Unterfunktion der Nebennierenrinde bestätigt. Dieser Fallbericht zeigt, dass sich Patienten in einer Addison-Krise mit akutem hämorrhagischem Durchfall präsentieren können. Durch Erbrechen und Durchfall kann es zu einem Kaliumverlust über den Gastrointestinaltrakt kommen, wodurch typische Elektrolytverschiebungen für einen Morbus Addison verschleiert werden. Im Zweifelsfall sollte bei jedem Patienten mit blutigem Durchfall zum Ausschluss eines Hypoadrenokortizismus eine Bestimmung der basalen Kortisolkonzentration erfolgen.
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Busch K, Chandra R, Buckenham T, Kiat H. Detection of Anomalous Cervical Internal Carotid Artery Branches by Colour Duplex Ultrasound. Eur J Vasc Endovasc Surg 2017; 53:776-782. [PMID: 28455146 DOI: 10.1016/j.ejvs.2017.03.008] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [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: 09/29/2016] [Accepted: 03/07/2017] [Indexed: 11/25/2022]
Abstract
OBJECTIVES Conventional anatomical descriptions of the cervical internal carotid artery (ICA) report that no branches arise from this segment. However reports of ICA branches exist. The study aim was to determine the prevalence of anomalous branches of the ICA using colour duplex ultrasound (CDU). METHODS Four hundred consecutive patients (800 carotid vessels) referred to a tertiary hospital vascular laboratory for investigation of carotid disease were included. A clear differentiation of a low resistive ICA and a high resistive external carotid artery (ECA) waveform was required. CDU was performed on a Philips IU22 ultrasound system with a 9-3 MHz linear array transducer employing a standard carotid imaging protocol. The origin of each ICA branch was identified using B-mode and CDU. Anatomical orientation of ICA branches and distance from bifurcation was recorded and spectral CDU analysis was performed. RESULTS Twenty ICA branches, tracking cephaladly, were detected in 16 patients (4%), or 2.5% (20/800) vessels. The median age was 73 years; 50% were female and 50% male. All patients demonstrated a single branch [unilateral anomaly (n = 12 patients), bilateral anomaly (n = 4) patients]. Eighty-five percent arose from the posterior wall of the ICA. The median distance from ICA bifurcation was 4 mm (range 0-18 mm). ICA branch diameters ranged from 1.2 mm to 2.4 mm (median 1.4 mm, mean 1.6 mm). Eighty percent of ICA branches had less than 50% stenosis. Spectral analysis revealed high resistive waveforms in all branches. CONCLUSIONS Branches from the ICA exist and can be characterised with CDU. Prevalence in a tertiary hospital referral cohort is 4%. Given their potential clinical implications, standard carotid imaging protocols should consider routine assessment and reporting of ICA branches.
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Affiliation(s)
- K Busch
- Faculty of Medicine and Health Sciences, Macquarie University, Sydney, Australia.
| | - R Chandra
- Interventional Neuroradiology Unit, Monash Imaging, Monash Health, Melbourne, Australia
| | - T Buckenham
- Monash Imaging, Monash Health and Department of Surgery, Monash University, Melbourne, Australia
| | - H Kiat
- Faculty of Medicine and Health Sciences, Macquarie University, Sydney, Australia
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Huang N, Kny M, Riediger F, Busch K, Schmidt S, Luft FC, Slevogt H, Fielitz J. Deletion of Nlrp3 protects from inflammation-induced skeletal muscle atrophy. Intensive Care Med Exp 2017; 5:3. [PMID: 28097512 PMCID: PMC5241267 DOI: 10.1186/s40635-016-0115-0] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [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: 07/22/2016] [Accepted: 12/29/2016] [Indexed: 11/17/2022] Open
Abstract
Background Critically ill patients develop atrophic muscle failure, which increases morbidity and mortality. Interleukin-1β (IL-1β) is activated early in sepsis. Whether IL-1β acts directly on muscle cells and whether its inhibition prevents atrophy is unknown. We aimed to investigate if IL-1β activation via the Nlrp3 inflammasome is involved in inflammation-induced atrophy. Methods We performed an experimental study and prospective animal trial. The effect of IL-1β on differentiated C2C12 muscle cells was investigated by analyzing gene-and-protein expression, and atrophy response. Polymicrobial sepsis was induced by cecum ligation and puncture surgery in Nlrp3 knockout and wild type mice. Skeletal muscle morphology, gene and protein expression, and atrophy markers were used to analyze the atrophy response. Immunostaining and reporter-gene assays showed that IL-1β signaling is contained and active in myocytes. Results Immunostaining and reporter gene assays showed that IL-1β signaling is contained and active in myocytes. IL-1β increased Il6 and atrogene gene expression resulting in myocyte atrophy. Nlrp3 knockout mice showed reduced IL-1β serum levels in sepsis. As determined by muscle morphology, organ weights, gene expression, and protein content, muscle atrophy was attenuated in septic Nlrp3 knockout mice, compared to septic wild-type mice 96 h after surgery. Conclusions IL-1β directly acts on myocytes to cause atrophy in sepsis. Inhibition of IL-1β activation by targeting Nlrp3 could be useful to prevent inflammation-induced muscle failure in critically ill patients. Electronic supplementary material The online version of this article (doi:10.1186/s40635-016-0115-0) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Nora Huang
- Experimental and Clinical Research Center (ECRC), Charité-Universitätsmedizin Berlin, Max Delbrück Center (MDC) for Molecular Medicine in the Helmholtz Association, Berlin, Germany.,Department of Cardiology, Heart Center Brandenburg and Medical University Brandenburg (MHB), Bernau, Germany
| | - Melanie Kny
- Experimental and Clinical Research Center (ECRC), Charité-Universitätsmedizin Berlin, Max Delbrück Center (MDC) for Molecular Medicine in the Helmholtz Association, Berlin, Germany
| | - Fabian Riediger
- Experimental and Clinical Research Center (ECRC), Charité-Universitätsmedizin Berlin, Max Delbrück Center (MDC) for Molecular Medicine in the Helmholtz Association, Berlin, Germany.,Department of Cardiology and Pneumology, Medical University Brandenburg (MHB), Brandenburg, Germany
| | - Katharina Busch
- Experimental and Clinical Research Center (ECRC), Charité-Universitätsmedizin Berlin, Max Delbrück Center (MDC) for Molecular Medicine in the Helmholtz Association, Berlin, Germany
| | - Sibylle Schmidt
- Experimental and Clinical Research Center (ECRC), Charité-Universitätsmedizin Berlin, Max Delbrück Center (MDC) for Molecular Medicine in the Helmholtz Association, Berlin, Germany
| | - Friedrich C Luft
- Experimental and Clinical Research Center (ECRC), Charité-Universitätsmedizin Berlin, Max Delbrück Center (MDC) for Molecular Medicine in the Helmholtz Association, Berlin, Germany.,Berlin Institute of Health (BIH), Kapelle-Ufer 2, 10117, Berlin, Germany
| | - Hortense Slevogt
- ZIK Septomics, Host Septomics, Jena, Germany.,Integrated Research and Treatment Center-Center for Sepsis Control and Care (CSCC), Jena University Hospital, Jena, Germany
| | - Jens Fielitz
- Experimental and Clinical Research Center (ECRC), Charité-Universitätsmedizin Berlin, Max Delbrück Center (MDC) for Molecular Medicine in the Helmholtz Association, Berlin, Germany. .,Department of Cardiology, Heart Center Brandenburg and Medical University Brandenburg (MHB), Bernau, Germany. .,Berlin Institute of Health (BIH), Kapelle-Ufer 2, 10117, Berlin, Germany.
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Intravaia F, Behunin RO, Henkel C, Busch K, Dalvit DAR. Failure of Local Thermal Equilibrium in Quantum Friction. Phys Rev Lett 2016; 117:100402. [PMID: 27636458 DOI: 10.1103/physrevlett.117.100402] [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] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/10/2016] [Indexed: 06/06/2023]
Abstract
Recent progress in manipulating atomic and condensed matter systems has instigated a surge of interest in nonequilibrium physics, including many-body dynamics of trapped ultracold atoms and ions, near-field radiative heat transfer, and quantum friction. Under most circumstances the complexity of such nonequilibrium systems requires a number of approximations to make theoretical descriptions tractable. In particular, it is often assumed that spatially separated components of a system thermalize with their immediate surroundings, although the global state of the system is out of equilibrium. This powerful assumption reduces the complexity of nonequilibrium systems to the local application of well-founded equilibrium concepts. While this technique appears to be consistent for the description of some phenomena, we show that it fails for quantum friction by underestimating by approximately 80% the magnitude of the drag force. Our results show that the correlations among the components of driven, but steady-state, quantum systems invalidate the assumption of local thermal equilibrium, calling for a critical reexamination of this approach for describing the physics of nonequilibrium systems.
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Affiliation(s)
| | - R O Behunin
- Department of Applied Physics, Yale University, New Haven, Connecticut 06511, USA
| | - C Henkel
- Institute of Physics and Astronomy, University of Potsdam, Karl-Liebknecht-Str. 24/25, 14476 Potsdam, Germany
| | - K Busch
- Max-Born-Institut, 12489 Berlin, Germany
- Humboldt-Universität zu Berlin, Institut für Physik, AG Theoretische Optik & Photonik, 12489 Berlin, Germany
| | - D A R Dalvit
- Theoretical Division, MS B213, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA
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13
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Busch K, Suchodolski JS, Kühner KA, Minamoto Y, Steiner JM, Mueller RS, Hartmann K, Unterer S. Clostridium perfringens
enterotoxin and Clostridium difficile
toxin A/B do not play a role in acute haemorrhagic diarrhoea syndrome in dogs. Vet Rec 2015; 176:253. [DOI: 10.1136/vr.102738] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Affiliation(s)
- K. Busch
- Clinic of Small Animal Medicine, LMU University of Munich; Veterinärstr. 13 Munich 80539 Germany
| | - J. S. Suchodolski
- Gastrointestinal Laboratory; Texas A&M University; College Station TX USA
| | - K. A. Kühner
- Clinic of Small Animal Medicine, LMU University of Munich; Veterinärstr. 13 Munich 80539 Germany
| | - Y. Minamoto
- Gastrointestinal Laboratory; Texas A&M University; College Station TX USA
| | - J. M. Steiner
- Gastrointestinal Laboratory; Texas A&M University; College Station TX USA
| | - R. S. Mueller
- Clinic of Small Animal Medicine, LMU University of Munich; Veterinärstr. 13 Munich 80539 Germany
| | - K. Hartmann
- Clinic of Small Animal Medicine, LMU University of Munich; Veterinärstr. 13 Munich 80539 Germany
| | - S. Unterer
- Clinic of Small Animal Medicine, LMU University of Munich; Veterinärstr. 13 Munich 80539 Germany
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14
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Busch K, Wehner A, Dorsch R, Hartmann K, Unterer S. [Acute haemorrhagic diarrhoea as a presenting sign in a dog with primary hypoadrenocorticism]. Tierarztl Prax Ausg K Kleintiere Heimtiere 2014; 42:326-330. [PMID: 25323215] [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] [Subscribe] [Scholar Register] [Received: 12/03/2013] [Accepted: 05/13/2014] [Indexed: 06/04/2023]
Abstract
A 7-year-old male castrated mixed breed dog was presented because of acute haemorrhagic vomiting and watery haemorrhagic diarrhoea. According to clinical signs, nonspecific clinicopathological abnormalities, normal electrolytes and a rapid improvement with fluid therapy, haemorrhagic gastroenteritis (HGE) was suspected. One month later the dog was represented with weakness and electrolyte changes characteristic for typical hypoadrenocorticism (hyperkalaemia and hyponatraemia) were found. The tentative diagnosis was confirmed using an ACTH stimulation test. This case report highlights that dogs with hypoadrenocorticism may be presented with acute haemorrhagic diarrhoea. Electrolyte changes characteristic for hypoadrenocorticism may not be present in case of gastrointestinal potassium loss because of vomiting and diarrhoea. To rule out hypoadrenocorticism, a basal cortisol measurement should be performed in every dog with acute haemorrhagic diarrhoea of unknown cause.
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Affiliation(s)
| | | | | | | | - S Unterer
- Dr. Stefan Unterer, Medizinische Kleintierklinik der Ludwig-Maximilians-Universität München, Veterinärstraße 13, 80539 München, E-Mail:
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15
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Unterer S, Busch K, Leipig M, Hermanns W, Wolf G, Straubinger RK, Mueller RS, Hartmann K. Endoscopically visualized lesions, histologic findings, and bacterial invasion in the gastrointestinal mucosa of dogs with acute hemorrhagic diarrhea syndrome. J Vet Intern Med 2013; 28:52-8. [PMID: 24205886 PMCID: PMC4895553 DOI: 10.1111/jvim.12236] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.5] [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: 05/17/2013] [Revised: 08/19/2013] [Accepted: 09/19/2013] [Indexed: 11/29/2022] Open
Abstract
BACKGROUND Etiology of hemorrhagic gastroenteritis (HGE) syndrome in dogs is unknown and histopathologic and microbial investigations have only been performed post mortem. OBJECTIVE To identify characteristic intra vitam endoscopic and histologic mucosal lesions, as well as bacterial species, within the mucosa of dogs with HGE. ANIMALS Ten dogs diagnosed with HGE were included. Eleven dogs with gastroduodenoscopy and different intestinal diseases were used as controls for microbial changes. Dogs pretreated with antibiotics or diagnosed with any disease known to cause bloody diarrhea were excluded from the study. METHODS In this prospective study, gastrointestinal biopsies were collected from 10 dogs with HGE. Endoscopic and histologic changes were assessed according to WSAVA guidelines. Biopsies from the stomach, duodenum, ileum, and colon were investigated by histology and by immunohistochemistry for the presence of Clostridium spp. and parvovirus. The first duodenal biopsy taken with a sterile forceps was submitted for bacterial culture. RESULTS Acute mucosal lesions were only found in the intestines, not in the stomach. Clostridium spp., identified as Clostridium perfringens in 6/9 cases, were detected on the small intestinal mucosa in all dogs with HGE, either by culture or immunohistopathology. In the control group, C. perfringens could only be cultured in one of 11 dogs. CONCLUSIONS AND CLINICAL IMPORTANCE The results of this study demonstrate an apparent association between C. perfringens and the occurrence of acute hemorrhagic diarrhea. The term "HGE," which implies the involvement of the stomach, should be renamed as "acute hemorrhagic diarrhea syndrome."
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Affiliation(s)
- S Unterer
- Clinic of Small Animal Medicine, LMU Munich, Munich, Germany
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16
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Leipig M, Busch K, Unterer S, Hermanns W. Histopathological Findings in Dogs with Haemorrhagic Gastroenteritis. J Comp Pathol 2013. [DOI: 10.1016/j.jcpa.2012.11.032] [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: 11/28/2022]
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17
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Staude I, von Freymann G, Essig S, Busch K, Wegener M. Waveguides in three-dimensional photonic-bandgap materials by direct laser writing and silicon double inversion. Opt Lett 2011; 36:67-69. [PMID: 21209689 DOI: 10.1364/ol.36.000067] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Three-dimensional complete photonic-bandgap materials offer unique opportunities regarding the integration of optical waveguide architectures in three dimensions. However, corresponding experimental realizations are truly sparse. Here, we fabricate such waveguides using direct laser writing and a silicon double-inversion procedure. The optical characterization is in good agreement with theoretical calculations, raising hopes that even more complex architectures may soon come into reach.
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Affiliation(s)
- I Staude
- Institut für Angewandte Physik and DFG-Center for Functional Nanostructures (CFN), Karlsruhe Institute of Technology (KIT), D-76128 Karlsruhe, Germany.
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18
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Röttgers S, Gombert M, Teigler-Schlegel A, Busch K, Gamerdinger U, Slany R, Harbott J, Borkhardt A. ALK fusion genes in children with atypical myeloproliferative leukemia. Leukemia 2010; 24:1197-200. [DOI: 10.1038/leu.2010.18] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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19
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Kolassa R, Mühlen H, Maraun M, Rose L, Hellenkamp A, Eberlein G, Donaubauer B, Busch K, Häußler RU, Jung R, Göbel R, Jansen I, Semmler S, Kohn W, Schulze-Schleppinghof B, Sack A, Bonnermann S, Thomas A. Nutzung des kontinuierlichen Glukosemonitorings (CGM) zur Ausschöpfung des Bolusmanagements von modernen Insulinpumpen. DIABETOL STOFFWECHS 2010. [DOI: 10.1055/s-0030-1253847] [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: 10/19/2022]
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20
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Staude I, Thiel M, Essig S, Wolff C, Busch K, von Freymann G, Wegener M. Fabrication and characterization of silicon woodpile photonic crystals with a complete bandgap at telecom wavelengths. Opt Lett 2010; 35:1094-1096. [PMID: 20364228 DOI: 10.1364/ol.35.001094] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
By using direct laser writing into a novel commercially available photoresist and a silicon-double-inversion procedure followed by tempering of the silicon structures, we realize high-quality centered-tetragonal woodpile photonic crystals with complete photonic bandgaps near 1.55 microm wavelength. The 6.9% gap-to-midgap ratio bandgap is evidenced by the comparison of measured transmittance and reflectance spectra with band-structure and scattering-matrix calculations.
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Affiliation(s)
- I Staude
- Institut für Angewandte Physik and DFG-Center for Functional Nanostructures (CFN), Karlsruhe Institute of Technology (KIT), D-76128 Karlsruhe, Germany.
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21
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Diener HC, Busch K, Weber R. Antithrombotische Therapien zur Schlaganfallprävention bei Patienten mit kardioembolischem Schlaganfall – Gegenwart und Zukunft. Akt Neurol 2009. [DOI: 10.1055/s-0029-1220441] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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22
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23
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Niederbichler A, Jokuszies A, Peters T, Steiert A, Knobloch K, Busch K, Vogt P. Extracorporeal life support devices (ECMO, ILA) in severely burned patients: Bridging the gap? Burns 2009. [DOI: 10.1016/j.burns.2009.06.179] [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: 11/24/2022]
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24
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Niesler FBP, Feth N, Linden S, Niegemann J, Gieseler J, Busch K, Wegener M. Second-harmonic generation from split-ring resonators on a GaAs substrate. Opt Lett 2009; 34:1997-9. [PMID: 19571978 DOI: 10.1364/ol.34.001997] [Citation(s) in RCA: 4] [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: 05/11/2023]
Abstract
We study second-harmonic generation from gold split-ring resonators on a crystalline GaAs substrate. By systematically varying the relative orientation of the split-ring resonators with respect to the incident linear polarization of light and the GaAs crystallographic axes, we unambiguously identify a nonlinear contribution that originates specifically from the interplay of the local fields of the split-ring resonators and the bulk GaAs second-order nonlinear-susceptibility tensor. The experimental results are in good agreement with theoretical modeling.
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Affiliation(s)
- F B P Niesler
- Institut for Angewandte Physik, DFG-Center for Functional Nanostructures, Universität Karlsruhe, Karlsruhe, Germany.
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25
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Weber KK, Lohmann T, Busch K, Donati-Hirsch I, Riel R. High frequency of unrecognized hypoglycaemias in patients with Type 2 diabetes is discovered by continuous glucose monitoring. Exp Clin Endocrinol Diabetes 2007; 115:491-4. [PMID: 17853331 DOI: 10.1055/s-2007-984452] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
AIMS To evaluate the use of a CGMS in the detection of hypoglycaemia in people with type 2 diabetes as an outpatient procedure. METHODS 31 type 2 diabetic patients underwent glucose monitoring by means of CGMS (Medtronic MiniMed) for up to three days. Patients took part in at least four SMBG (self monitoring blood glucose) tests per day. After three days of monitoring, the CGMS data was downloaded and analysed by a physician to identify the frequency of hypoglycaemias (< or =50 mg/dl) and borderline values (51-70 mg/dl), their duration and distribution. Findings were discussed with the patient and if necessary treatment was adjusted. Eight weeks later, monitoring was repeated to asses the effects of the adjusted treatment. RESULTS Average duration of sensor wear was 4.19 days. Correlation between the sensor and the SMBG readings was high. A high number of hypoglycaemias and borderline values were detected by the CGMS, most of them unrecognized by the patient. The frequency of hypoglycaemias and borderline values just as the duration could be significantly reduced from first to second monitoring. CONCLUSION Using the CGMS in type 2 diabetic patients achieved the detection of numerous hypoglycaemias and borderline values both nocturnal and/or unnoticed. The CGMS provides accurate data, which cannot be achieved by conventional SMBG tests. That opens the possibility for treatment adjustment and improvement in metabolic control. For patients it provides a better understanding of the effects of insulin or oral agents, nutrition and exercises to their glucose level.
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Affiliation(s)
- K K Weber
- Department of Internal Medicine, St.-Johannes-Hospital Dortmund, Johannesstrasse 9-17, 44137 Dortmund, Germany.
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26
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Woessmann W, Damm-Welk C, Busch K, Burkhardt B, Viehmann S, Oschlies I, Klapper W, Zimmermann M, Harbott J, Reiter A. Prognostic significance of circulating tumor cells in bone marrow or peripheral blood detected by qualitative and quantitative PCR in pediatric NPM-ALK positive anaplastic large cell lymphoma. J Clin Oncol 2007. [DOI: 10.1200/jco.2007.25.18_suppl.9559] [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: 11/20/2022] Open
Abstract
9559 Background: Clinical and histopathological characteristics have limited prognostic value for children with anaplastic large cell lymphoma (ALCL). We evaluated the presence, extent and prognostic impact of circulating tumor cells in bone marrow (BM) and peripheral blood (PB) of children and adolescents with NPM-ALK positive ALCL by real-time quantitative PCR for NPM-ALK. Methods: Qualitative and TaqMan-based quantitative PCR assays targeting NPM-ALK were developed with a sensitivity to detect 1 NPM-ALK positive cell among 105 cells. Numbers of NPM-ALK transcripts were normalized to 104 copies ABL (NCN). BM was analyzed from 80 and PB from 52 German patients registered into the subsequent protocols NHL-BFM95 and ALCL99. Results: BM was positive for NPM-ALK in 47.5% of patients, and positivity was significantly correlated with clinical stage, mediastinal or visceral involvement, microscopic BM involvement, and histological subtype, but not with skin or CNS involvement. Qualitative and quantitative PCR results in BM and PB strongly correlated. BM PCR was associated with the cumulative incidence of relapses (CI-R): CI-R was 50±10% for 38 PCR-positive and 15±7% for 42 PCR-negative patients (p10 NCN NPM-ALK in BM had a CI-R of 71±14% compared to a CI-R of 18±6% for 59 patients with =10 NCN (p10 NCN NPM-ALK in BM, clinical risk factors (skin, mediastinal or visceral involvement) and atypical histological subtype, only >10 NCN NPM-ALK remained a significant poor prognostic factor with a risk ratio of 4.74 (1.57–14.3; p<0.006). Conclusions: The detection of NPM-ALK positive cells by PCR in BM is associated with advanced stage disease, visceral involvement and atypical histology. Quantitative PCR in BM or PB allows identification of 20% of patients experiencing 60% of all relapses with an event-free survival of 20%. No significant financial relationships to disclose.
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Affiliation(s)
- W. Woessmann
- University Children`s Hospital, Giessen, Germany; University Hospital Schleswig-Holstein, Campus Kie, Kiel, Germany
| | - C. Damm-Welk
- University Children`s Hospital, Giessen, Germany; University Hospital Schleswig-Holstein, Campus Kie, Kiel, Germany
| | - K. Busch
- University Children`s Hospital, Giessen, Germany; University Hospital Schleswig-Holstein, Campus Kie, Kiel, Germany
| | - B. Burkhardt
- University Children`s Hospital, Giessen, Germany; University Hospital Schleswig-Holstein, Campus Kie, Kiel, Germany
| | - S. Viehmann
- University Children`s Hospital, Giessen, Germany; University Hospital Schleswig-Holstein, Campus Kie, Kiel, Germany
| | - I. Oschlies
- University Children`s Hospital, Giessen, Germany; University Hospital Schleswig-Holstein, Campus Kie, Kiel, Germany
| | - W. Klapper
- University Children`s Hospital, Giessen, Germany; University Hospital Schleswig-Holstein, Campus Kie, Kiel, Germany
| | - M. Zimmermann
- University Children`s Hospital, Giessen, Germany; University Hospital Schleswig-Holstein, Campus Kie, Kiel, Germany
| | - J. Harbott
- University Children`s Hospital, Giessen, Germany; University Hospital Schleswig-Holstein, Campus Kie, Kiel, Germany
| | - A. Reiter
- University Children`s Hospital, Giessen, Germany; University Hospital Schleswig-Holstein, Campus Kie, Kiel, Germany
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27
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Busch K, Keller T, Fuchs U, Yeh RF, Harbott J, Klose I, Wiemels J, Novosel A, Reiter A, Borkhardt A. Identification of two distinct MYC breakpoint clusters and their association with various IGH breakpoint regions in the t(8;14) translocations in sporadic Burkitt-lymphoma. Leukemia 2007; 21:1739-51. [PMID: 17541401 DOI: 10.1038/sj.leu.2404753] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The chromosomal translocation t(8;14) is the hallmark of Burkitt's-lymphoma (BL) and fuses the proto-oncogene c-MYC to the IGH locus. We analyzed the genomic structure of MYC/IGH fusions derived from a large series of 78 patients with t(8;14) and asked (i) whether distinct breakpoint clusters exist within the MYC gene and (ii) whether any pairwise association between particular IGH and MYC breakpoints exist. Identification of such associations will help elucidate the etiology of the breaks on the MYC locus. Scan statistic analyses revealed two distinct, but large clusters within c-MYC containing 60/78 (77%) of the breakpoints. Clusters 1 and 2 were 560 and 779 bp in length within a 4555 bp breakpoint cluster region. Breaks within IGH switch mu and joining region did not differ with respect to their corresponding MYC breakpoints. However, there was a highly significant correlation between breakpoints 5' of MYC cluster 1 and fusions to IGH switch gamma region and breakpoints downstream of MYC cluster 2 and fusions to IGH switch alpha region (chi(2)-test: P<0.005). Chromatin changes governing choice of IGH-Fc region recombination may parallel changes in the MYC gene 5' region chromatin leading to some degree of coordinated ontological specificity in breakpoint location.
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MESH Headings
- Adolescent
- Burkitt Lymphoma/genetics
- Child
- Child, Preschool
- Chromosome Breakage
- Chromosomes, Human, Pair 14/genetics
- Chromosomes, Human, Pair 8/genetics
- DNA, Neoplasm/genetics
- Female
- Genes, myc
- Humans
- Immunoglobulin Heavy Chains/genetics
- In Situ Hybridization, Fluorescence
- Male
- Molecular Sequence Data
- Proto-Oncogene Mas
- Repetitive Sequences, Nucleic Acid
- Translocation, Genetic/genetics
- Tumor Cells, Cultured
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Affiliation(s)
- K Busch
- Department of Pediatric Hematology and Oncology, Justus-Liebig-University, Giessen, Germany
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Abstract
The success of modern burn therapy is based on an understanding of the pathophysiology and application of burn intensive care implying fluid resuscitation and management of pulmonary or other organ failure. With the development of early eschar excision and wound closure by immediate grafting, survival and cosmetic outcome were further improved. Especially in post-acute therapy, early physical rehabilitation, early reintegration, and early plastic surgical correction of the sequelae are indispensable for the outcome.
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Affiliation(s)
- P M Vogt
- Klinik und Poliklinik für Plastische, Hand- und Wiederherstellungschirurgie, Zentrum für Schwerbrandverletzte, Medizinische Hochschule Hannover, Carl-Neuberg-Strasse 1, 30625, Hannover.
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Knobloch K, Gohritz A, Busch K, Spies M, Vogt PM. Hirudo medicinalis-Anwendungen in der plastischen und rekonstruktiven Mikrochirurgie - eine Literaturübersicht. HANDCHIR MIKROCHIR P 2007; 39:103-7. [PMID: 17497605 DOI: 10.1055/s-2007-965138] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022] Open
Abstract
Medical leech therapy has enjoyed a renaissance in the world of reconstructive microsurgery during recent years. Especially venous congestion is decreased using hirudo medicinalis application such as following replantation of amputated fingers or congested flaps. They provide a temporary relief to venous engorgement whilst venous drainage is re-established. Living in symbiosis with Aeromonas hydrophila, who can digest the sixfold blood meal related to their body weight, and a broad number of anticoagulant agents such as the thrombin inhibitor hirudin, apyrase as well as collagenase, hyaluronidase, Factor Xa inhibitor and fibrinase I and II, leeches decrease venous congestion. Laser Doppler flowmetry could demonstrate a significant increase in superficial skin perfusion following leech application 16 mm around the biting zone. Following the initial blood meal accounting for about 2.5 ml, the anticoagulant effect of the various leeches enzymes follows within the next 5-6 hours, which both account for the beneficial effects. Infection associated with leech therapy is a documented complication of leech application, with reported incidences ranging from 2.4 to 20 % and a chinolone antibiotic is currently recommended to face the potential Aeromonas hydrophila infection. Anemia is a second adverse effect during medicinal leech application which has to be taken account with repetitive blood samples. Besides the successful applications of leeches in various applications in plastic and reconstructive microsurgery, randomized-controlled trials are pending to elucidate the value of hirudo medicinalis according to evidence-based criteria above from case series and case studies.
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Affiliation(s)
- K Knobloch
- Plastische, Hand- und Wiederherstellungschirurgie, Medizinische Hochschule Hannover, Carl-Neuberg-Strasse 1, 30625 Hannover.
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Abstract
The surgical management of defects in the pelvic region is a great surgical challenge. Primary tumor recurrences have to be addressed and local infections require appropriate therapy such as rigorous debridement and antibiotic therapy. Plastic surgery provides tissue reconstruction by well perfused flaps and also reestablishment of anatomic structures in the ano-genital region. An early reconstruction also reduces the wound complications of adjuvant or post oncologic therapy and reduces the rate of wound healing problems.
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Affiliation(s)
- P M Vogt
- Klinik für Plastische, Hand- und Wiederherstellungschirurgie, der Medizinischen Hochschule Hannover, Univ.-Prof. Dr. med. P. M. Vogt, Carl-Wiechert-Allee 1, 30625 Hannover.
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Bobbert T, Göhring I, Mai K, Busch K, Krotzky A, Catchpoole G, Wilmitzer L, Pfeiffer A, Spranger J. Establishment of metabolome measurement in human plasma. Exp Clin Endocrinol Diabetes 2006. [DOI: 10.1055/s-2006-933029] [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: 10/19/2022]
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Vogt PM, Busch K, Spies M, Lahoda LU, Kall S, Klima U, Jokuszies A. [Breast cancer -- plastic surgical strategies for the treatment of tumour infiltration of the thoracic wall and brachial plexus]. ACTA ACUST UNITED AC 2006; 127:407-11. [PMID: 16341986 DOI: 10.1055/s-2005-836584] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Extensive locoregional recurrency or metastatic involvement of brachial plexopathy is a condition that is often associated with advanced systemic breast cancer. In the past the role of surgeon was restricted due to a scepticism as to whether any benefit will be provided for the patient. In the recent 25 years however safe and refined plastic surgical approaches have been developed that provide more options to treat even complex recurrent disease. The strategy of plastic surgery in an interdisciplinary approach of gynecology, oncology and radiotherapy as well as thoracic surgery is outlined.
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Affiliation(s)
- P M Vogt
- Klinik für Plastische, Hand und Wiederherstellungschirurgie, Klinikum Hannover Oststadt und Medizinische Hochschule Hannover.
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Busch K, Lehmann P, Chen H, Stewart M, Seidel D. Die Kombination mit Insulin führt bei Patienten, die unter der Fixkombination Rosiglitazon/Metformin unzureichend eingestellt sind zu einer besseren Blutzuckereinstellung als die Umstellung auf Insulin allein. DIABETOL STOFFWECHS 2006. [DOI: 10.1055/s-2006-943777] [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: 10/19/2022]
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Abstract
Insulin glulisine (glulisine), a human insulin analogue with a rapid-acting time-action profile, has been developed to fulfil the mealtime (bolus) insulin requirement in patients with diabetes. The aim of this multinational, multi-centre, controlled, open-label, randomized, parallel-group study was to compare the efficacy and safety of insulin glulisine (glulisine) to that of insulin lispro (lispro) in adults diagnosed with Type 1 diabetes. Of the 683 patients randomized, 672 received treatment (339 patients received glulisine, 333 patients received lispro). Over the 26-week study, a similar reduction in mean HbA1c occurred in both groups (adjusted mean change from baseline -0.14% in both groups). The basal insulin dose was relatively unchanged from baseline in the glulisine group but increased in the lispro group (glulisine: 0.12 IU vs. lispro: 1.82 IU; p = 0.0001). As a consequence, total daily insulin dose decreased in the glulisine group but increased in the lispro group (glulisine: -0.86 IU vs. lispro: 1.01 IU; p = 0.0123). There was no relevant difference between the two groups in the reporting of symptomatic hypoglycaemia (overall, nocturnal and severe). This study demonstrates that glulisine provides equivalent glycaemic control to lispro. The clinical relevance of any difference in total daily insulin dose remains to be established.
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Affiliation(s)
- M Dreyer
- Bethanien-Krankenhaus GmbH, Hamburg, Germany.
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Busch K, Aust M, Spies M, Vogt P. HIT Typ 2 als Folge der Thrombembolieprophylaxe bei freiem mikrochirurgischem Gewebetransfer mit Heparin. Konsequenzen für das perioperative Management? HANDCHIR MIKROCHIR P 2005. [DOI: 10.1055/s-2005-864861] [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: 10/19/2022] Open
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Aust M, Kolokythas P, Das Gupta K, Busch K, Vogt PM. Mikrochirurgische Techniken in der Plastischen Chirurgie unter DRG-Bedingungen. HANDCHIR MIKROCHIR P 2005. [DOI: 10.1055/s-2005-864859] [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: 10/19/2022] Open
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Abstract
Surgical or multimodal therapy of tumors of the pelvis often results in complex defects leading to functional and structural deficits, with the inability to sit or even lie without pain. Multimodal therapy may cause induration of soft tissues and muscles, obstruction of the small bowel, fistulas, and infected cavities. Early soft tissue reconstruction, preferably with myocutaneous flaps, reduces postoperative problems in these patients by early coverage of defects, closure of cavities, and prevention of wound healing complications and therefore allows earlier rehabilitation.
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Affiliation(s)
- K Das Gupta
- Klinik für Plastische, Hand- und Wiederherstellungschirurgie, Klinikum Hannover Oststadt-Medizinische Hochschule Hannover.
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Abstract
AIMS Diabetic patients with podopathy (diabetic foot syndrome) may need protective footwear, be it customized or industrially produced stock 'diabetic' shoes (SDS). The effectiveness of each type of 'diabetic' shoe needs to be proven clinically, e.g. in terms of prevention of foot ulceration. The following study assesses a new German SDS, the LucRo shoe, which consists of rocker-shaped walking sole, a standardized shock absorption insole, and soft uppers without stiff toe-caps. The LucRo SDS has been registered as a Medicinal Product according to the European Community Guideline 93/42/EC. PATIENTS AND METHODS A total of 92 high-risk diabetic patients (mean age 63 years, duration of diabetes 13 years) with healed foot ulcer were recruited prospectively over 31 months; 87 patients suffered from polyneuropathy, 24 patients had peripheral ischaemic vessel disease. One group of patients (n = 60) received the LucRo SDS and wore them, while the remaining patients (n = 32) did not receive the SDS and were forced to use their normal footwear. This allocation reflects the haphazard reimbursement policies of the individual patients' health insurance, and is in accordance with the current German legislation. The patients were followed up for up to 42 months until the first foot ulcer relapse, or the end of the study. RESULTS There were no differences between the groups concerning age, sex, type and duration of diabetes, prevalence of polyneuropathy and peripheral ischaemic vessel disease, frequency of foot care and mortality rate. The first year annual rate of foot ulcer relapse was significantly different between the groups: 60% without SDS vs. 15% with SDS. The overall cumulative ulcer-free survival was significantly greater with SDS (P < 0.0001, log rank test). CONCLUSION The LucRo stock 'diabetic' shoe appears effective in the prevention of foot re-ulceration in high-risk patients with diabetic podopathy.
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Affiliation(s)
- K Busch
- Diabetes-Fussambulanz, MNR-Klinik der Heinrich-Heine-Universität Düsseldorf, Düsseldorf, Germany
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Asatryan AA, Busch K, McPhedran RC, Botten LC, de Sterke CM, Nicorovici NA. Two-dimensional Green tensor and local density of states in finite-sized two-dimensional photonic crystals. ACTA ACUST UNITED AC 2003. [DOI: 10.1088/0959-7174/13/1/302] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Botten LC, McPhedran RC, Nicorovici NA, Asatryan AA, de Sterke CM, Robinson PA, Busch K, Smith GH, Langtry TN. Rayleigh Multipole Methods for Photonic Crystal Calculations. ACTA ACUST UNITED AC 2003. [DOI: 10.2528/pier02010802] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Abstract
The study of single molecules opens a new dimension in understanding nature down to its finest ramifications. While much progress was achieved in the last decade concerning the detection techniques, suitable techniques for manipulating and handling the biomolecules still bear a challenge. Primarily, the task is keeping an individual, active molecule of a certain lifespan in the spot. Here, we will focus on techniques for the functional immobilization of (single) molecules on surfaces to enable their observation at one position over a time period. Presenting the main methods of reversible immobilization we will accentuate the chelator lipid concept as combining all features prerequisite for functional, reversible and well-defined immobilization. This will also show that single molecule research in principle is the synthesis of an insight into the function of nature and nano-biotechnology (manipulation): thus of analytics, construction, and back.
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Affiliation(s)
- K Busch
- Institut für Physiologische Chemie, Philipps-Universiät Marburg, Germany
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Schilling J, Wehrspohn RB, Birner A, Müller F, Hillebrand R, Gösele U, Leonard SW, Mondia JP, Genereux F, Driel HMV, Kramper P, Sandoghdar V, Busch K. A model system for two-dimensional and three-dimensional photonic crystals: macroporous silicon. ACTA ACUST UNITED AC 2001. [DOI: 10.1088/1464-4258/3/6/362] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Asatryan AA, Busch K, McPhedran RC, Botten LC, de Sterke CM, Nicorovici NA. Two-dimensional Green's function and local density of states in photonic crystals consisting of a finite number of cylinders of infinite length. Phys Rev E Stat Nonlin Soft Matter Phys 2001; 63:046612. [PMID: 11308973 DOI: 10.1103/physreve.63.046612] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/27/2000] [Revised: 10/24/2000] [Indexed: 05/23/2023]
Abstract
Using the exact theory of multipole expansions, we construct the two-dimensional Green's function for photonic crystals, consisting of a finite number of circular cylinders of infinite length. From this Green's function, we compute the local density of states (LDOS), showing how the photonic crystal affects the radiation properties of an infinite fluorescent line source embedded in it. For frequencies within the photonic band gap of the infinite crystal, the LDOS decreases exponentially inside the crystal; within the bands, we find "hot" and "cold" spots. Our method can be extended to three dimensions as well as to treating disorder and represents an important and efficient tool for the design of photonic crystal devices.
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Affiliation(s)
- A A Asatryan
- School of Physics, University of Sydney, Sydney, NSW 2006, Australia
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Zhang F, Wolff MW, Williams D, Busch K, Lang SC, Murhammer DW, Linhardt RJ. Affinity purification of secreted alkaline phosphatase produced by baculovirus expression vector system. Appl Biochem Biotechnol 2001; 90:125-36. [PMID: 11297388 DOI: 10.1385/abab:90:2:125] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Human secreted alkaline phosphatase (SEAP) was produced in a stably-transformed Spodoptera frugiperda Sf-9 insect cell line (Sfb4GalT) following infection with a recombinant Autographa californica multiple nuclear polyhedrovirus containing the SEAP gene under control of the polyhedrin promoter. An affinity chromatographic column prepared by linking 4-amino-benzylphosphonic acid to histidyl-expoxy-Sepharose was used to isolate SEAP from the cell supernatant following removal of cells and virus and 10-fold concentration through ultrafiltration. We found that the binding of SEAP on the affinity matrix follows the Langmuir isotherm model. In addition, either recycling SEAP sample through the column for 24 h or loading high SEAP concentrations resulted in a high-purity product. Some nonspecific binding of protein on the matrix occurred when low concentrations of SEAP sample were loaded. Finally, we found that SEAP binding occurs rapidly, i.e., within 30 min of adding the SEAP sample to the affinity matrix.
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Affiliation(s)
- F Zhang
- Department of Chemical and Biochemical Engineering, University of Iowa, Iowa City 52242, USA
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Asatryan A, Fabre S, Busch K, McPhedran R, Botten L, de Sterke M, Nicorovici NA. Two-dimensional local density of states in two-dimensional photonic crystals. Opt Express 2001; 8:191-196. [PMID: 19417803 DOI: 10.1364/oe.8.000191] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
We calculate the two-dimensional local density of states (LDOS) for two-dimensional photonic crystals composed of a finite cluster of circular cylinders of infinite length. The LDOS determines the dynamics of radiation sources embedded in a photonic crystal. We show that the LDOS decreases exponentially inside the crystal for frequencies within a photonic band gap of the associated infinite array and demonstrate that there exist ;;hot' and ;;cold' spots inside the cluster even for wavelengths inside a gap, and also for wavelengths corresponding to pass bands. For long wavelengths the LDOS exhibits oscillatory behavior in which the local density of states can be more than 30 times higher than the vacuum level.
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de Sterke CM, Busch K. Introduction. Opt Express 2001; 8:166. [PMID: 19417800 DOI: 10.1364/oe.8.000166] [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] [Indexed: 05/27/2023]
Abstract
Progress in optics is intimately connected to the development of novel optical materials. This includes advances in synthesizing such materials as well as improvements in their theoretical understanding. Photonic Crystals represent a particularly lucid illustration of this principle: The advent of advanced microstructuring techniques has allowed the realization of two- and three-dimensional periodic arrays on sub-micron scales that provide Bragg-scattering for electromagnetic waves with frequencies in the near IR and the visible. Photonic band structure computations accurately predict crystal structures that posses complete photonic bandgaps and the minimal refractive index contrast that is needed to open them. The controlled fabrication, characterization and optimal design of cavities and waveguiding structures in photonic band gap materials represents another fascinating challenge for material scientists, spectroscopists and theorists alike. Finally, the incorporation of nonlinear and optically active materials into Photonic Crystal structures along with a detailed understanding of the optical properties of the resulting composite systems, may enhance the technological utility of Photonic Crystals over and above the conventional linear structures.
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Abstract
We introduce a novel algorithm for band structure computations based on multigrid methods. In addition, we demonstrate how the results of these band structure calculations may be used to compute group velocities and effective photon masses. The results are of direct relevance to studies of pulse propagation in such materials.
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Abstract
We present a detailed study of the mode structure of inverse opal photonic crystal materials with an emphasis on their potential use in optical trapping and cooling. In particular, we analyze the modes corresponding to the upper and lower band edges of a high refractive index inverse opal, i.e., the so-called ;;air' and ;;dielectric' bands. In the dielectric band, we demonstrate optical intensity enhancements of two orders of magnitude which may facilitate nonlinear optical effects in the solid. In the air band, dipolar optical trapping potentials for cold atoms in the voids arise when these modes are excited by an external laser field. In addition, we discuss aspects of atom cooling through the polarization gradients provided by these modes. The results suggest that optical trapping and cooling may be achieved within a photonic crystal using a single laser source.
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Busch K, Vats N, John S, Sanders BC. Radiating dipoles in photonic crystals. Phys Rev E Stat Phys Plasmas Fluids Relat Interdiscip Topics 2000; 62:4251-4260. [PMID: 11088954 DOI: 10.1103/physreve.62.4251] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/04/2000] [Indexed: 05/23/2023]
Abstract
The radiation dynamics of a dipole antenna embedded in a photonic crystal are modeled by an initially excited harmonic oscillator coupled to a non-Markovian bath of harmonic oscillators representing the colored electromagnetic vacuum within the crystal. Realistic coupling constants based on the natural modes of the photonic crystal, i.e., Bloch waves and their associated dispersion relation, are derived. For simple model systems, well-known results such as decay times and emission spectra are reproduced. This approach enables direct incorporation of realistic band structure computations into studies of radiative emission from atoms and molecules within photonic crystals. We therefore provide a predictive and interpretative tool for experiments in both the microwave and optical regimes.
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Affiliation(s)
- K Busch
- Department of Physics, University of Toronto, 60 St. George Street, Toronto, Ontario, Canada M5S 1A7 and Institut fur Theorie der Kondensierten Materie, Universitat Karlsruhe, P.O. Box 6980, 76128 Karlsruhe, Germany
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Busch K, Piehler J, Fromm H. Plant succinic semialdehyde dehydrogenase: dissection of nucleotide binding by surface plasmon resonance and fluorescence spectroscopy. Biochemistry 2000; 39:10110-7. [PMID: 10955999 DOI: 10.1021/bi000589e] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Recent kinetic studies revealed distinct modes of inhibition of mitochondrial Arabidopsis thaliana succinic semialdehyde dehydrogenase (At-SSADH1) by AMP and ATP. Inhibition of SSADH by ATP may represent an important mechanism of feedback regulation of the GABA shunt by the respiratory chain. Here we used two approaches to investigate the interaction of ATP with At-SSADH1. Cofactor displacement studies based on the reduced fluorescence intensity of free NADH versus that of enzyme-bound NADH revealed that both AMP and ATP decreased NADH-At-SSADH1 complex formation. The competitive inhibitor AMP displaced all bound NADH, while ATP, a noncompetitive inhibitor, could not, even in great excess, release all NADH from its binding site. To assess the effect of ATP on NAD-At-SSADH, we employed surface plasmon resonance to monitor nucleotide binding to immobilized At-SSADH1. For this, we used a Strep-tag II modified derivative of At-SSADH1 (designated ST-At-SSADH1). The tagged enzyme was tightly and reversibly captured by StrepTactin, which was covalently immobilized on a CM5 chip. The binding constants for NAD(+) and ATP were determined from titration curves and were in good agreement with the constants obtained from enzyme kinetics. Surface plasmon resonance measurements confirmed that ATP binds to a site different from the binding site for NAD(+). GTP competed with ATP. However, only ATP increased the dissociation constant of NAD(+) from SSADH. This explains the reduced affinity of NAD(+)/NADH to At-SSADH1 in the presence of ATP, as revealed by enzymatic kinetics, and supports our model of feedback regulation of SSADH and the GABA shunt by ATP.
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Affiliation(s)
- K Busch
- Departments of Plant Sciences and Biological Chemistry, The Weizmann Institute of Science, Rehovot, Israel.
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