656 results on '"Michael Schwab"'
Search Results
2. Notes on Contributors
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Paulo de Assis and Michael Schwab
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- 2019
3. Untimeliness in Contemporary Times
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Paulo de Assis and Michael Schwab
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- 2019
4. Experimental Systems: Contemporaneity, Untimeliness, and Artistic Research
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Paulo de Assis and Michael Schwab
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- 2019
5. Working the Contemporary: History as a Project of Crisis, Today
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Paulo de Assis and Michael Schwab
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- 2019
6. Part 3: Problematising the Contemporary
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Paulo de Assis and Michael Schwab
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- 2019
7. Aporetic Temporalisations and Postconceptual Realism
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Paulo de Assis and Michael Schwab
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- 2019
8. The Crackle of Contemporaneity
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Paulo de Assis and Michael Schwab
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- 2019
9. On Aesthetic Experience as Anachronic Experience
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Paulo de Assis and Michael Schwab
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- 2019
10. Part 2: Contemporary Practices
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Paulo de Assis and Michael Schwab
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- 2019
11. Part 1: The Contemporary and the Untimely
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Paulo de Assis and Michael Schwab
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- 2019
12. The Question of the Contemporary in Agamben, Nancy, Danto: Between Nietzsche’s Artist and Nietzsche’s Spectator
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Paulo de Assis and Michael Schwab
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- 2019
13. The Contemporary: In the Midst of Multiple Hurricanes of Time
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Paulo de Assis and Michael Schwab
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- 2019
14. Half-Title, Title, Copyright
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Paulo de Assis and Michael Schwab
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- 2019
15. On the Question of Contemporaneity Today
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Paulo de Assis and Michael Schwab
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- 2019
16. Cover
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Paulo de Assis and Michael Schwab
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- 2019
17. Table of Contents
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Paulo de Assis and Michael Schwab
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- 2019
18. LSVT-BIG therapy in Parkinson’s disease: physiological evidence for proprioceptive recalibration
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Manuel Peterka, Thorsten Odorfer, Michael Schwab, Jens Volkmann, and Daniel Zeller
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Proprioception ,Amplitude ,Training ,Pointing error ,LSVT-big therapy ,Neurology. Diseases of the nervous system ,RC346-429 - Abstract
Abstract Background There is growing evidence for proprioceptive dysfunction in patients with Parkinson’s disease (PD). The Lee Silvermann Voice Treatment-BIG therapy (LSVT-BIG), a special training program aiming at an increase of movement amplitudes in persons with PD (PwPD), has shown to be effective on motor symptoms. LSVT-BIG is conceptionally based on improving bradykinesia, in particular the decrement of repetitive movements, by proprioceptive recalibration. Objective To assess proprioceptive impairment in PwPD as compared to matched controls and to probe potential recalibration effects of the LSVT-BIG therapy on proprioception. Methods Proprioceptive performance and fine motor skills were assessed in 30 PwPD and 15 matched controls. Measurements with significant impairment in PwPD were chosen as outcome parameters for a standardized 4 weeks amplitude-based training intervention (LSVT-BIG) in 11 PwPD. Proprioceptive performance served as primary outcome measure. Secondary outcome measures included the motor part of the MDS-UPDRS, the nine-hole-peg test, and a questionnaire on quality of life. Post-interventional assessments were conducted at weeks 4 and 8. Results Compared to the control group, PwPD showed significantly larger pointing errors. After 4 weeks of LSVT-BIG therapy and even more so after an additional 4 weeks of continued training, proprioceptive performance improved significantly. In addition, quality of life improved as indicated by a questionnaire. Conclusion LSVT-BIG training may achieve a recalibration of proprioceptive processing in PwPD. Our data indicates a probable physiological mechanism of a symptom-specific, amplitude-based behavioral intervention in PwPD.
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- 2020
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19. Corrigendum: Signal Disruption Leads to Changes in Bacterial Community Population
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Michael Schwab, Celine Bergonzi, Jonathan Sakkos, Christopher Staley, Qian Zhang, Michael J. Sadowsky, Alptekin Aksan, and Mikael Elias
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quorum sensing ,lactonase ,biofilm ,microbial community ,silica encapsulation ,Microbiology ,QR1-502 - Published
- 2021
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20. Correction: Evaluation of biological and enzymatic quorum quencher coating additives to reduce biocorrosion of steel.
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Siqian Huang, Celine Bergonzi, Michael Schwab, Mikael Elias, and Randall E Hicks
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Medicine ,Science - Abstract
[This corrects the article DOI: 10.1371/journal.pone.0217059.].
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- 2021
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21. Gut microbiota impairs insulin clearance in obese mice
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Kevin P. Foley, Soumaya Zlitni, Brittany M. Duggan, Nicole G. Barra, Fernando F. Anhê, Joseph F. Cavallari, Brandyn D. Henriksbo, Cassandra Y. Chen, Michael Huang, Trevor C. Lau, Roxanne Plante, Michael Schwab, André Marette, and Jonathan D. Schertzer
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Diabetes ,Glucose ,Insulin ,Microbiota ,Obesity ,Internal medicine ,RC31-1245 - Abstract
Objective: Hyperinsulinemia can be both a cause and consequence of obesity and insulin resistance. Hyperinsulinemia can result from increased insulin secretion and/or reduced insulin clearance. While many studies have focused on mechanisms triggering insulin secretion during obesity, the triggers for changes in insulin clearance during obesity are less defined. In this study, we investigated the role of the microbiota in regulating insulin clearance during diet-induced obesity. Methods: Blood glucose and insulin clearance were tested in conventional male mice treated with antibiotics and germ-free mice colonized with microbes from mice that were fed a control (chow) diet or an obesogenic high-fat diet (HFD). The composition of the fecal microbiota was analyzed using 16S rRNA sequencing. Results: Short-term HFD feeding and aging did not alter insulin clearance in the mice. Oral antibiotics mitigated impaired blood insulin clearance in the mice fed an HFD for 12 weeks or longer. Germ-free mice colonized with microbes from HFD-fed donor mice had impaired insulin but not C-peptide clearance. Microbe-transmissible insulin clearance impairment was only observed in germ-free mice after more than 6 weeks post-colonization upon HFD feeding. Five bacterial taxa predicted >90% of the variance in insulin clearance. Mechanistically, impaired insulin clearance was associated with lower levels of hepatic Ceacam-1 but increased liver and skeletal muscle insulin-degrading enzyme (IDE) activity. Conclusions: Gut microbes regulate insulin clearance during diet-induced obesity. A small cluster of microbes or their metabolites may be targeted for mitigating defects in insulin clearance and hyperinsulinemia during the progression of obesity and type 2 diabetes.
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- 2020
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22. Structural and Biochemical Characterization of AaL, a Quorum Quenching Lactonase with Unusual Kinetic Properties
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Celine Bergonzi, Michael Schwab, Tanushree Naik, David Daudé, Eric Chabrière, and Mikael Elias
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Medicine ,Science - Abstract
Abstract Quorum quenching lactonases are enzymes that are capable of disrupting bacterial signaling based on acyl homoserine lactones (AHL) via their enzymatic degradation. In particular, lactonases have therefore been demonstrated to inhibit bacterial behaviors that depend on these chemicals, such as the formation of biofilms or the expression of virulence factors. Here we characterized biochemically and structurally a novel representative from the metallo-β-lactamase superfamily, named AaL that was isolated from the thermoacidophilic bacterium Alicyclobacillus acidoterrestris. AaL is a potent quorum quenching enzyme as demonstrated by its ability to inhibit the biofilm formation of Acinetobacter baumannii. Kinetic studies demonstrate that AaL is both a proficient and a broad spectrum enzyme, being capable of hydrolyzing a wide range of lactones with high rates (kcat/KM > 105 M−1.s−1). Additionally, AaL exhibits unusually low KM values, ranging from 10 to 80 µM. Analysis of AaL structures bound to phosphate, glycerol, and C6-AHL reveals a unique hydrophobic patch (W26, F87 and I237), involved in substrate binding, possibly accounting for the enzyme’s high specificity. Identifying the specificity determinants will aid the development of highly specific quorum quenching enzymes as potential therapeutics.
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- 2018
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23. Signal Disruption Leads to Changes in Bacterial Community Population
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Michael Schwab, Celine Bergonzi, Jonathan Sakkos, Christopher Staley, Qian Zhang, Michael J. Sadowsky, Alptekin Aksan, and Mikael Elias
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quorum sensing ,lactonase ,biofilm ,microbial community ,silica encapsulation ,Microbiology ,QR1-502 - Abstract
The disruption of bacterial signaling (quorum quenching) has been proven to be an innovative approach to influence the behavior of bacteria. In particular, lactonase enzymes that are capable of hydrolyzing the N-acyl homoserine lactone (AHL) molecules used by numerous bacteria, were reported to inhibit biofilm formation, including those of freshwater microbial communities. However, insights and tools are currently lacking to characterize, understand and explain the effects of signal disruption on complex microbial communities. Here, we produced silica capsules containing an engineered lactonase that exhibits quorum quenching activity. Capsules were used to design a filtration cartridge to selectively degrade AHLs from a recirculating bioreactor. The growth of a complex microbial community in the bioreactor, in the presence or absence of lactonase, was monitored over a 3-week period. Dynamic population analysis revealed that signal disruption using a quorum quenching lactonase can effectively reduce biofilm formation in the recirculating bioreactor system and that biofilm inhibition is concomitant to drastic changes in the composition, diversity and abundance of soil bacterial communities within these biofilms. Effects of the quorum quenching lactonase on the suspension community also affected the microbial composition, suggesting that effects of signal disruption are not limited to biofilm populations. This unexpected finding is evidence for the importance of signaling in the competition between bacteria within communities. This study provides foundational tools and data for the investigation of the importance of AHL-based signaling in the context of complex microbial communities.
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- 2019
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24. Seção especial - The Exposition of Practice as Research as Experimental Systems
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Michael Schwab
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Arts in general ,NX1-820 ,Visual arts ,N1-9211 - Abstract
Seção especial - The Exposition of Practice as Research as Experimental Systems Michael Schwab Editor do Journal for Artistic Research (JAR) Tradução Osmar Yang e Yara Guasque Artigo publicado originalmente em Inglês (SCHWAB, Michael. “The Exposition of Practice as Research as Experimental Systems”, 2014, pp. 31-40) como capítulo do livro CRISPIN, Darla; GILMORE, Bob. (Eds.). Artistic Experimentation in Music. An Anthology. Leuven: Leuven University Press, 2014.
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- 2019
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25. Evaluation of biological and enzymatic quorum quencher coating additives to reduce biocorrosion of steel.
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Siqian Huang, Celine Bergonzi, Michael Schwab, Mikael Elias, and Randall E Hicks
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Medicine ,Science - Abstract
Microbial colonization can be detrimental to the integrity of metal surfaces and lead to microbiologically influenced corrosion (MIC). Biocorrosion is a serious problem for aquatic and marine industries in the world. In Minnesota (USA), where this study was conducted, biocorrosion severely affects the maritime transportation industry. The anticorrosion activity of a variety of compounds, including chemical (magnesium peroxide) and biological (surfactin, capsaicin, and gramicidin) molecules were investigated as coating additives. We also evaluated a previously engineered, extremely stable, non-biocidal enzyme known to interfere in bacterial signaling, SsoPox (a quorum quenching lactonase). Experimental steel coupons were submerged in water from the Duluth Superior Harbor (DSH) for 8 weeks in the laboratory. Biocorrosion was evaluated by counting the number and the coverage of corrosion tubercles on coupons and also by ESEM imaging of the coupon surface. Three experimental coating additives significantly reduced the formation of corrosion tubercles: surfactin, magnesium peroxide and the quorum quenching lactonase by 31%, 36% and 50%, respectively. DNA sequence analysis of the V4 region of the bacterial 16S rRNA gene revealed that these decreases in corrosion were associated with significant changes in the composition of bacterial communities on the steel surfaces. These results demonstrate the potential of highly stable quorum quenching lactonases to provide a reliable, cost-effective method to treat steel structures and prevent biocorrosion.
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- 2019
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26. Expositions in the research catalog / Exposições no catálogo de pesquisa
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Michael Schwab
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Arts in general ,NX1-820 ,Visual arts ,N1-9211 - Abstract
O Research Catalog, RC (Catálogo de Pesquisa)e o Journal for Artistic Research, JAR (Revista de Pesquisa Artística)são projetos interligados, mas com metas e propósitos muito diferentes. O RC é um espaço de trabalho gratuito online e basicamente privativo que permite a (auto-)publicação e pesquisa artística. JAR é um periódico acadêmico, avaliado pelos pares, de livre acesso, para a publicação e disseminação de pesquisa artística. JAR atua como o primeiro de uma série de portais planejados, especializados para pesquisas selecionadas publicadas no RC que utilizam a tecnologia disponibilizada, incluindo a interface de design e o procedimento integrado de envio e publicação.
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- 2018
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27. Emotional Intolerance and Core Features of Anorexia Nervosa: A Dynamic Interaction during Inpatient Treatment? Results from a Longitudinal Diary Study.
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Esther Stroe-Kunold, Hans-Christoph Friederich, Tatjana Stadnitski, Daniela Wesche, Wolfgang Herzog, Michael Schwab, and Beate Wild
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Medicine ,Science - Abstract
OBJECTIVE:The role of emotion dysregulation with regard to the psychopathology of anorexia nervosa (AN) is increasingly discussed. It is both assumed that AN symptoms have an impact on difficulties in tolerating aversive emotions and that-conversely-emotion dysregulation influences AN. To date, such conclusions are drawn on the basis of cross-sectional data not allowing for inferences on the temporal dynamics. The current study investigates the longitudinal interaction between emotional intolerance and core AN symptoms over the course of inpatient treatment by comparing patients with high (BMI
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- 2016
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28. Morphokinetic analysis of early human embryonic development and its relationship to endometriosis resection: a retrospective time-lapse study using the KIDScore™ D3 and D5 implantation data algorithm
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Saskia-Laureen Herbert, Claudia Staib, Theresa Wallner, Sanja Löb, Carolin Curtaz, Michael Schwab, Achim Wöckel, and Sebastian Häusler
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Obstetrics and Gynecology ,General Medicine - Abstract
Research question Does complete resection of endometriosis improve embryo quality as assessed by morphokinetic parameters using time-lapse microscopy? Design For this retrospective study we analysed 237 fertilised, cultured and transferred embryos from 128 fresh IVF and/ or ICSI transfer cycles. Endometriosis was confirmed or excluded by laparoscopy. Patients were stimulated with recombinant FSH using GnRH agonist and antagonist protocols. After fertilisation, a time-lapse incubation system was used for observation. Embryo quality was assessed using the KIDScore™ D3 and D5 implantation data algorithm. Results The analysis showed a median KIDScore™ D5 of 2.6 (on a scale of 1 to 9.9) for embryos from patients with endometriosis without complete resection. The control group without endometriosis achieved a score of 6.8 (p = 0.003). The median score for embryos from endometriosis patients with complete resection was 7.2, which was a significant increase compared to embryos from patients without complete resection (p = 0.002). We observed an effect size of r = 0.4 for complete resection versus no resection of endometriosis using the KIDScore™ D5. There were no differences in KIDScore™ D3 between the three patient groups. Pregnancy and miscarriage rates showed the same clinical trends. In three of our four case series of patients who underwent IVF/ ICSI cycles before and after complete resection, we found a marked improvement in embryo quality after complete resection. Conclusions Complete resection of endometriosis could significantly improve the otherwise poor embryo quality of patients undergoing IVF-procedures. The data, therefore, strongly support recommending surgery to patients with endometriosis prior to assisted reproduction.
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- 2023
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29. An analytical model to determine the impact force of drone strikes
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Uli Burger, Christian Hühne, Florian Franke, and Michael Schwab
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Mass distribution ,Aviation ,business.industry ,Orientation (computer vision) ,Computer science ,Aerospace Engineering ,Stiffness ,Transportation ,Nuclear reactor ,Drone ,law.invention ,Drone collision · Unmanned aerial vehicle · Analytic approach · Impact force · Drone strike · Numerical calculation ,law ,Windshield ,medicine ,Impact ,medicine.symptom ,Aerospace engineering ,business - Abstract
In addition to the well-known threats of bird and hail strikes, small unmanned aerial vehicles (sUAV) pose a new threat to manned aviation. Determining the severity of collisions between sUAVs and aircraft structures is essential for the safe use and integration of drones in airspace. A generic analytical calculation model needs to be developed to supplement the existing test and simulation data. This paper presents an analytic model for drone collisions with perpendicular and inclined targets. The targets have a rigid or elastic material behavior. The aircraft impact model, which is used for the design of nuclear reactor structures, is transferred and adjusted for sUAV impacts to calculate the impact force. A mass- and a burst load distribution are needed as input parameters. Both distributions are determined for an sUAV design depending on the flight direction. Compared to previous calculations, the new approach is to consider a moving target structure, which produces more realistic results. We compare the calculation results with simulation data from sUAV collisions with a commercial airliner windshield from the literature. The calculations show plausible results and a good agreement with literature data. Subsequently, the influence of the input parameters on the impact force is investigated. We see that spring stiffness, target mass, burst load distribution and damping have minor influence on the overall impact force. The impact velocity, mass distribution and flight orientation on the other hand have a major influence on the impact force. Further tests are needed to validate the impact model.
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- 2021
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30. Patients with higher vitamin D levels show stronger improvement of self-reported depressive symptoms in psychogeriatric day-care setting
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Jürgen Deckert, Stefan Unterecker, Maike Scherf-Clavel, Christine Daniels, Alexandra Herr, Linda D. Zech, and Michael Schwab
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Anti-depressive treatment ,medicine.medical_specialty ,Neurology ,Geriatric Psychiatry ,030209 endocrinology & metabolism ,vitamin D deficiency ,03 medical and health sciences ,0302 clinical medicine ,Rating scale ,Internal medicine ,medicine ,Vitamin D and neurology ,Humans ,030212 general & internal medicine ,ddc:610 ,Prospective Studies ,Vitamin D ,Prospective cohort study ,Vitamin D deficiency ,Biological Psychiatry ,Depression (differential diagnoses) ,Aged ,business.industry ,Depression ,Psychiatry and Preclinical Psychiatric Studies - Original Article ,Psycho-geriatrics ,medicine.disease ,Psychiatry and Mental health ,Quality of Life ,Geriatric Depression Scale ,Neurology (clinical) ,Self Report ,business ,Hormone - Abstract
Depression is a common psychiatric disorder among geriatric patients that decreases the quality of life and increases morbidity and mortality. Vitamin D as a neuro-steroid hormone might play a role in the onset and treatment of depression. In the present study, the association between depressive symptoms and vitamin D concentration in serum was evaluated. 140 patients of a psychogeriatric day-care unit were included. The geriatric depression scale (GDS) and the Hamilton depression rating scale (HDRS) were assessed at the beginning and end of treatment, GDS scores additionally 6 weeks after discharge from the day-care unit. Vitamin D levels were measured at the beginning of the treatment, routinely. Patients with levels below 30 µg/L were treated with 1000 IU vitamin D per day. There was no association between the severity of depressive symptoms and the concentration of vitamin D at the beginning of the treatment. Patients with higher vitamin D levels showed a stronger decline of depressive symptoms measured by the GDS during their stay in the day-care unit. We provide evidence that vitamin D serum levels might influence antidepressant therapy response in a geriatric population. Prospective studies are necessary to determine which patients may profit from add-on vitamin D therapy.
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- 2021
31. Multidrug-resistant high-risk clonal Escherichia coli lineages occur along an antibiotic residue gradient in the Baltic Sea
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Phillip Lübcke, Stefan E. Heiden, Timo Homeier-Bachmann, Jürgen A. Bohnert, Christian Schulze, Elias Eger, Michael Schwabe, Sebastian Guenther, and Katharina Schaufler
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Water supply for domestic and industrial purposes ,TD201-500 - Abstract
Abstract The global spread of multidrug-resistant Escherichia coli threatens human, animal, and environmental health. Despite the recognition of water bodies as potential reservoirs, research on antimicrobial resistance (AMR) and antibiotic residues in the Baltic Sea is limited. In this study, we examined the presence of ESBL-producing E. coli in surface water in northeastern Germany. We then conducted phenotypic and genotypic analyses of the strains, which encompassed AMR and heavy metal/metalloid tolerance, biofilm formation, and detailed plasmid examination. In addition, we used solid-phase extraction with ultra-high performance liquid chromatography and mass spectrometry to quantify antibiotic residues. Our analysis identified 30 ESBL-producing E. coli isolates, some of which were associated with clinically relevant high-risk clonal lineages. We detected antibiotic residues in the environmental samples, but the antibiotic concentrations were significantly lower compared to wastewater samples. These results suggest that the Baltic Sea surface water could serve as a reservoir for ESBL-producing E. coli and clinically relevant antibiotics.
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- 2024
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32. Analysis of mobile-originated interference in coexisting UMTS networks.
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Michael Schwab and Peter Seidenberg
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- 2002
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33. Reliability and Reproducibility of a Novel Grading System for Lesions of the Ligamentous-Fossa-Foveolar Complex in Young Patients Undergoing Open Hip Preservation Surgery
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Vera Maren Stetzelberger, Corinne Andrea Zurmühle, Matthieu Hanauer, Jonathan Laurençon, Darius Marti, Malin Kristin Meier, Vlad Popa, Joseph Michael Schwab, and Moritz Tannast
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Orthopedics and Sports Medicine ,610 Medicine & health - Abstract
Background: Several classification systems based on arthroscopy have been used to describe lesions of the ligamentum teres (LT) in young active patients undergoing hip-preserving surgery. Inspection of the LT and associated lesions of the adjuvant fovea capitis and acetabular fossa is limited when done arthroscopically but is much more thorough during open surgical hip dislocation. Therefore, we propose a novel grading system based on our findings during surgical dislocation comprising the full spectrum of ligamentous-fossa-foveolar complex (LFFC) lesions. Purpose: To determine (1) intraobserver reliability and (2) interobserver reproducibility of our new grading system. Study Design: Cohort study (diagnosis); Level of evidence, 3. Methods: We performed this validation study on 211 hips (633 images in total) with surgical hip dislocation (2013-2021). We randomly selected 5 images per grade for each LFFC item to achieve an equal representation of all grades (resulting in 75 images). The ligament, fossa, and fovea were subcategorized into normal, inflammation, degeneration, partial, and complete defects. All surgeries were performed in a standardized way by a single surgeon. The femur was disarticulated using a bone hook, the LT was inspected, documented and resected, then the fossa and fovea were documented with the femoral head in full dislocation using a 70° arthroscope. Six observers with different levels of expertise in hip-preserving surgery independently conducted the measurements twice, and intraclass correlation coefficients (ICC) were calculated to determine (1) intraobserver reliability and (2) interobserver reproducibility of the novel grading system. Results: For intraobserver reliability, excellent ICCs were found in both the junior and the experienced raters for grading the ligament, fossa, fovea, and total LFFC (ICCs ranged from 0.91 to 0.99 for the LFFC score). We found excellent interobserver reproducibility between raters for all items of the LFFC (all interobserver ICCs ≥ 0.76). Conclusion: Our new grading system for lesions of the LFFC is highly reliable and reproducible. It covers the full spectrum of damage more precisely than arthroscopic classifications do and offers a scientific basis for standardized intraoperative evaluation.
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- 2022
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34. Imbalanced Inflammatory Responses in Preterm and Term Cord Blood Monocytes and Expansion of the CD14+CD16+ Subset upon Toll-like Receptor Stimulation
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Kirsten Glaser, David Kern, Christian P. Speer, Nicolas Schlegel, Michael Schwab, Ulrich H. Thome, Christoph Härtel, and Clyde J. Wright
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Organic Chemistry ,General Medicine ,Toll-like receptor signaling ,neonatal immunology ,cytokines ,Catalysis ,Computer Science Applications ,Inorganic Chemistry ,monocyte subsets ,inflammation ,cord blood ,preterm infants ,Physical and Theoretical Chemistry ,monocytes ,Molecular Biology ,Spectroscopy - Abstract
Developmentally regulated features of innate immunity are thought to place preterm and term infants at risk of infection and inflammation-related morbidity. Underlying mechanisms are incompletely understood. Differences in monocyte function including toll-like receptor (TLR) expression and signaling have been discussed. Some studies point to generally impaired TLR signaling, others to differences in individual pathways. In the present study, we assessed mRNA and protein expression of pro- and anti-inflammatory cytokines in preterm and term cord blood (CB) monocytes compared with adult controls stimulated ex vivo with Pam3CSK4, zymosan, polyinosinic:polycytidylic acid, lipopolysaccharide, flagellin, and CpG oligonucleotide, which activate the TLR1/2, TLR2/6, TLR3, TLR4, TLR5, and TLR9 pathways, respectively. In parallel, frequencies of monocyte subsets, stimulus-driven TLR expression, and phosphorylation of TLR-associated signaling molecules were analyzed. Independent of stimulus, pro-inflammatory responses of term CB monocytes equaled adult controls. The same held true for preterm CB monocytes—except for lower IL-1β levels. In contrast, CB monocytes released lower amounts of anti-inflammatory IL-10 and IL-1ra, resulting in higher ratios of pro-inflammatory to anti-inflammatory cytokines. Phosphorylation of p65, p38, and ERK1/2 correlated with adult controls. However, stimulated CB samples stood out with higher frequencies of intermediate monocytes (CD14+CD16+). Both pro-inflammatory net effect and expansion of the intermediate subset were most pronounced upon stimulation with Pam3CSK4 (TLR1/2), zymosan (TR2/6), and lipopolysaccharide (TLR4). Our data demonstrate robust pro-inflammatory and yet attenuated anti-inflammatory responses in preterm and term CB monocytes, along with imbalanced cytokine ratios. Intermediate monocytes, a subset ascribed pro-inflammatory features, might participate in this inflammatory state.
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- 2023
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35. Female Adnexal Tumour of Probable Wolffian Origin (FATWO): Review of the Literature
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Theresa Barbara Hübner, Michael Schwab, Elena Hartmann, Doris Mayr, Achim Wöckel, Daniel Herr, Annette Thurner, and Thorsten A. Bley
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medicine.medical_specialty ,Hysterectomy ,biology ,business.industry ,CD117 ,medicine.medical_treatment ,borderline tumour ,Adnextumor ,Obstetrics and Gynecology ,Adnexal tumour ,medicine.disease ,FATWO ,Metastasis ,Mesonephric duct ,adnexal tumour ,Borderlinetumor ,Maternity and Midwifery ,medicine ,biology.protein ,Review/Übersicht ,Endocrine system ,GebFra Science ,Radiology ,business ,Surgical treatment - Abstract
FATWO (female adnexal tumour of probable Wolffian origin) denotes a rare tumour of the female adnexa which has been described in nearly 80 cases worldwide and which presumably originates in the remains of the Wolffian ducts. In 10 to 20 percent of patients, a metastasis or recurrence was seen subsequently and for this reason, a malignant potential is attributed to the FATWO. Because of the small number of cases, there is no clear therapeutic recommendation. The method of choice currently is surgical treatment with hysterectomy and adnexectomy. The benefit of radio- and chemotherapies is not clear and a small number of treatment attempts with imatinib have been made in cases of CD117 positivity or treatment attempts on an endocrine basis. This work provides an overview of the literature on epidemiology, imaging and histopathological diagnostic features as well as therapeutic options of this same tumour form.FATWO (female adnexal tumour of propable Wolffian origin) bezeichnet einen seltenen Tumor der weiblichen Adnexe, der weltweit in knapp 80 Fällen beschrieben wurde und dessen Ursprung vermutlich in den Residuen der Wolffʼschen Gänge liegt. Bei 10 bis 20 Prozent der Patientinnen zeigte sich im Verlauf eine Metastasierung oder ein Rezidiv, weshalb dem FATWO ein malignes Potenzial zugeschrieben wird. Aufgrund der kleinen Fallzahl existiert keine klare Therapieempfehlung. Methode der Wahl ist derzeit eine operative Sanierung mit Hysterektomie und Adnexektomie. Der Nutzen von Radio- und Chemotherapien ist nicht eindeutig, vereinzelt wurden Therapieversuche mit Imatinib bei CD117-Positivität oder Therapieversuche auf endokriner Basis unternommen. Diese Arbeit zeigt eine Literaturübersicht über Epidemiologie, bildgebende und histopathologische Diagnosemerkmale sowie Therapieoptionen dieser seltenen Tumorform.
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- 2019
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36. Colostrum as a source of ESBL-Escherichia coli in feces of newborn calves
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Lisa Bachmann, Laura Weber, Wendy Liermann, Harald M. Hammon, Cora Delling, Franziska Dengler, Katharina Schaufler, Michael Schwabe, Elias Eger, Karsten Becker, Anne Schütz, and Timo Homeier-Bachmann
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Medicine ,Science - Abstract
Abstract The aim of the present study was to determine if colostrum and the equipment for harvesting and feeding colostrum are sources of fecal ESBL/AmpC-producing Escherichia coli (ESBL/AmpC-E. coli) in calves. Therefore, 15 male calves fed with pooled colostrum on a dairy farm and held individually in an experimental barn, the colostrum pool and the equipment for harvesting and feeding colostrum were sampled and analyzed for the occurrence of ESBL/AmpC-E. coli. The ESBL-AmpC-E. coli suspicious isolates were subjected to whole-genome sequence analysis. Forty-three of 45 fecal samples were tested positive for ESBL/AmpC-E. coli. In the colostrum sample and in the milking pot, we also found ESBL/AmpC-E. coli. All 45 E. coli isolates were ESBL-producers, mainly commensal sequence type (ST) 10, but also human-extraintestinal pathogenic E. coli ST131 and ST117 were found. The clonal identity of six fecal isolates with the ESBL-E. coli isolate from the colostrum and of five fecal isolates with the strain from the milking pot demonstrates that the hygiene of colostrum or the colostrum equipment can play a significant role in the spread of ESBL-E. coli. Effective sanitation procedures for colostrum harvesting and feeding equipment are crucial to reduce the ESBL-E. coli shedding of neonatal dairy calves.
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- 2024
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37. Control of a COVID-19 outbreak in a nursing home by general screening and cohort isolation in Germany, March to May 2020
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Elisabeth Richter, Ulrich Vogel, Michael Schwab, Manuel Krone, and Annette Noffz
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Male ,medicine.medical_specialty ,Isolation (health care) ,Epidemiology ,030204 cardiovascular system & hematology ,Asymptomatic ,Disease Outbreaks ,03 medical and health sciences ,COVID-19 Testing ,0302 clinical medicine ,nursing ,Germany ,Virology ,Intervention (counseling) ,Homes for the Aged ,Humans ,Medicine ,Infection control ,030212 general & internal medicine ,Aged ,Retrospective Studies ,Aged, 80 and over ,SARS-CoV-2 ,business.industry ,Outbreaks ,Public Health, Environmental and Occupational Health ,COVID-19 ,Outbreak ,Retrospective cohort study ,infection control ,Nursing Homes ,Outcome and Process Assessment, Health Care ,Family medicine ,Quarantine ,Cohort ,Female ,medicine.symptom ,business ,Follow-Up Studies - Abstract
Elderly care facilities have become a major focus of coronavirus disease (COVID-19) control. Here, we describe an outbreak of COVID-19 in a nursing home in Germany from 8 March to 4 May 2020 (58 days), and the effect of an intervention of general screening and cohort isolation. COVID-19 cases among residents and staff were recorded on a daily basis from the first positive SARS-CoV-2 test from a resident on 8 March 2020, until 4 May 2020 when the last staff member was classified COVID-19 negative. Eighty of 160 residents (50%) and 37 of 135 staff members (27%) tested positive for SARS-CoV-2. Twenty-seven of the 80 residents were asymptomatic but tested positive during the first general screening. Cohort isolation of SARS-CoV-2 positive residents by reorganising the facility proved to be a major effort. After the intervention, four further asymptomatic residents tested positive in follow-up screenings within a period of 6 days, and were possibly infected prior to the intervention. Thereafter, no further infections were recorded among residents. The described outbreak was controlled by implementing general screening and rigorous cohort isolation, providing a blueprint for similar facilities.
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- 2021
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38. Hypertension Experience of Foreign-Born West African Immigrant Women in the United States: Access to and Utilization of Health Services
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Assumpta Onyinye Ude and Michael Schwab
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West african ,Health services ,Foreign born ,media_common.quotation_subject ,Political science ,Immigration ,Socioeconomics ,media_common - Abstract
BackgroundHypertension is a major risk factor for cardiovascular disease and the leading cause of premature deaths in the United States. Hypertension is a commonly reported chronic disease in foreign-born-adult immigrants living in the United States, and psychosocial-cultural factors such as lack of health insurance and poor transportation services have been reported particularly among foreign-born immigrant women with hypertension and other chronic diseases. However, little is known about the socio-cultural factors that influence access to and utilization of hypertension health services in West-African-born immigrant women in the United States.MethodsThis study utilized a qualitative design with a phenomenological approach to interview a purposeful sample of fifteen West-African-born immigrant women that reported diagnosis of hypertension (12 with health insurance and 3 without health insurance) in the Washington District of Columbia Metropolitan area. The Patient Centered Access to Health Care Model guided the conceptual framework of the study. Thematic analysis was used to identify patterns and generate categories and themes.ResultsFive themes emerged from the analysis: Health Insurance Coverage, Frequency of Hypertension Care Visits, Interaction with HCP, Culturally Sensitive HCP, and HTN Self-Care Incentives. Eighty percent of participants had medical insurance and transportation services, but delayed seeking HTN care because their health care providers did not listen to their concerns or discuss their preferences before prescribing treatment. More than 60 percent of the women reported that clinicians did not listen to their concerns or provide culturally appropriate guidance during their visits.ConclusionsThese findings could be helpful for larger scale studies, or smaller comparative studies in other regions of the United States. Cultural competence training should be included in the continuing education curriculum of healthcare providers serving the West-African-born immigrant population.
- Published
- 2020
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39. Gut microbiota impairs insulin clearance in obese mice
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Brandyn D. Henriksbo, Michael Schwab, Cassandra Y. Chen, Kevin P. Foley, Roxanne Plante, Brittany M. Duggan, Jonathan D. Schertzer, Nicole G. Barra, Joseph F. Cavallari, André Marette, Michael Huang, Trevor C. Lau, Fernando F. Anhê, and Soumaya Zlitni
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0301 basic medicine ,Blood Glucose ,Male ,lcsh:Internal medicine ,medicine.medical_specialty ,medicine.drug_class ,medicine.medical_treatment ,Antibiotics ,Mice, Obese ,030209 endocrinology & metabolism ,Type 2 diabetes ,Gut flora ,Diet, High-Fat ,03 medical and health sciences ,Feces ,Mice ,0302 clinical medicine ,Insulin resistance ,Diabetes mellitus ,Internal medicine ,Hyperinsulinism ,RNA, Ribosomal, 16S ,medicine ,Hyperinsulinemia ,Animals ,Insulin ,Obesity ,lcsh:RC31-1245 ,Molecular Biology ,2. Zero hunger ,biology ,business.industry ,Microbiota ,Diabetes ,Cell Biology ,medicine.disease ,biology.organism_classification ,3. Good health ,Gastrointestinal Microbiome ,Mice, Inbred C57BL ,030104 developmental biology ,Endocrinology ,Glucose ,Liver ,Insulin Resistance ,business - Abstract
Objective Hyperinsulinemia can be both a cause and consequence of obesity and insulin resistance. Hyperinsulinemia can result from increased insulin secretion and/or reduced insulin clearance. While many studies have focused on mechanisms triggering insulin secretion during obesity, the triggers for changes in insulin clearance during obesity are less defined. In this study, we investigated the role of the microbiota in regulating insulin clearance during diet-induced obesity. Methods Blood glucose and insulin clearance were tested in conventional male mice treated with antibiotics and germ-free mice colonized with microbes from mice that were fed a control (chow) diet or an obesogenic high-fat diet (HFD). The composition of the fecal microbiota was analyzed using 16S rRNA sequencing. Results Short-term HFD feeding and aging did not alter insulin clearance in the mice. Oral antibiotics mitigated impaired blood insulin clearance in the mice fed an HFD for 12 weeks or longer. Germ-free mice colonized with microbes from HFD-fed donor mice had impaired insulin but not C-peptide clearance. Microbe-transmissible insulin clearance impairment was only observed in germ-free mice after more than 6 weeks post-colonization upon HFD feeding. Five bacterial taxa predicted >90% of the variance in insulin clearance. Mechanistically, impaired insulin clearance was associated with lower levels of hepatic Ceacam-1 but increased liver and skeletal muscle insulin-degrading enzyme (IDE) activity. Conclusions Gut microbes regulate insulin clearance during diet-induced obesity. A small cluster of microbes or their metabolites may be targeted for mitigating defects in insulin clearance and hyperinsulinemia during the progression of obesity and type 2 diabetes.
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- 2020
40. Bewegungsberatung für Ältere in der hausärztlichen Versorgung: zwei Praxishilfen
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Karin Meng, Hermann Faller, Stefan Peters, and Michael Schwab
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General Medicine - Abstract
Zusammenfassung Hintergrund Beratung durch Ärzte in Bezug auf Lebensstil im Allgemeinen und das Bewegungsverhalten im Speziellen steht seit dem Inkrafttreten des Präventionsgesetzes in Deutschland wieder vermehrt im Fokus. Auch für die Bewegungstherapie spielt die Anknüpfung an ärztliche Beratung eine wichtige Rolle. Die Erwartungen an ärztliche Beratung sind dabei durchaus hoch, wohingegen es eine Vielzahl an Barrieren zu geben scheint. In einem Projekt (PATEN im Rahmen vom Forschungsverbund Capital4Health) zur Bewegungsförderung im Seniorenwohnstift wurde ein Informations- bzw. Schulungsangebot erprobt. Dabei wurden Praxishilfen entwickelt, die es Ärzten erleichtern sollen, das Thema Bewegung im zeitlich begrenzten Rahmen strukturiert anzusprechen. Konzeption Die beiden Praxishilfen (Tischvorlagen) beinhalten ein potenzielles Ablaufschema für eine Kurzberatung nach den so genannten 5 A‘s sowie eine grafische Darstellung von gängigen Bewegungsempfehlungen für Ältere. Letztere beziehen sich vornehmlich auf die deutschen Nationalen Empfehlungen für Bewegung und Bewegungsförderung. Die 5A-Methode (Ask / Assess, Agree, Advise, Assist, Arrange) ist evidenzbasiert, eignet sich für die primäre Gesundheitsversorgung und wird von gängigen Leitlinien empfohlen. Diskussion Interventionen zur Bewegungsförderung in der Arztpraxis können von unterschiedlichster Dauer und inhaltlicher Ausrichtung sein. Die vorliegenden Praxishilfen können zur flexiblen Umsetzung genutzt werden. Sie sind dabei auch von Bewegungsfachleuten und evtl. anderen Berufsgruppen einsetzbar.
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- 2018
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41. Temperatures above 37°C increase virulence of a convergent Klebsiella pneumoniae sequence type 307 strain
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Justus U. Müller, Michael Schwabe, Lena-Sophie Swiatek, Stefan E. Heiden, Rabea Schlüter, Max Sittner, Jürgen A. Bohnert, Karsten Becker, Evgeny A. Idelevich, Sebastian Guenther, Elias Eger, and Katharina Schaufler
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K. pneumoniae ,temperature-dependent virulence ,hypermucoviscosity ,hypervirulence ,plasmid copy number ,transcriptomics ,Microbiology ,QR1-502 - Abstract
BackgroundConvergence of Klebsiella pneumoniae (KP) pathotypes has been increasingly reported in recent years. These pathogens combine features of both multidrug-resistant and hypervirulent KP. However, clinically used indicators for hypervirulent KP identification, such as hypermucoviscosity, appear to be differentially expressed in convergent KP, potential outbreak clones are difficult to identify. We aimed to fill such knowledge gaps by investigating the temperature dependence of hypermucoviscosity and virulence in a convergent KP strain isolated during a clonal outbreak and belonging to the high-risk sequence type (ST)307.MethodsHypermucoviscosity, biofilm formation, and mortality rates in Galleria mellonella larvae were examined at different temperatures (room temperature, 28°C, 37°C, 40°C and 42°C) and with various phenotypic experiments including electron microscopy. The underlying mechanisms of the phenotypic changes were explored via qPCR analysis to evaluate plasmid copy numbers, and transcriptomics.ResultsOur results show a temperature-dependent switch above 37°C towards a hypermucoviscous phenotype, consistent with increased biofilm formation and in vivo mortality, possibly reflecting a bacterial response to fever-like conditions. Furthermore, we observed an increase in plasmid copy number for a hybrid plasmid harboring carbapenemase and rmpA genes. However, transcriptomic analysis revealed no changes in rmpA expression at higher temperatures, suggesting alternative regulatory pathways.ConclusionThis study not only elucidates the impact of elevated temperatures on hypermucoviscosity and virulence in convergent KP but also sheds light on previously unrecognized aspects of its adaptive behavior, underscoring its resilience to changing environments.
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- 2024
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42. The NTCP-inhibitor Myrcludex B: Effects on Bile Acid Disposition and Tenofovir Pharmacokinetics
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Thomas Bruckner, A. Alexandrov, Antje Blank, Nicolas Hohmann, Stephan Urban, Juergen Burhenne, Johanna Weiss, Katrin Meier, Gerd Mikus, Hans H. Maurer, Walter E. Haefeli, Michael Schwab, Annette Eidam, Mathias Haag, Meyer, and Sfj van de Graaf
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Adult ,Male ,0301 basic medicine ,Organic anion transporter 1 ,medicine.drug_class ,CYP3A ,Injections, Subcutaneous ,Administration, Oral ,Organic Anion Transporters, Sodium-Dependent ,Pharmacology ,Antiviral Agents ,Risk Assessment ,Bile Acids and Salts ,Lipopeptides ,Young Adult ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Pharmacokinetics ,Cholestasis ,medicine ,Cytochrome P-450 CYP3A ,Humans ,Drug Interactions ,Pharmacology (medical) ,Prospective Studies ,Tenofovir ,SLC10A1 ,Symporters ,biology ,Bile acid ,Chemistry ,Middle Aged ,Hepatitis B ,medicine.disease ,Taurocholic acid ,Up-Regulation ,030104 developmental biology ,biology.protein ,Reverse Transcriptase Inhibitors ,Female ,030211 gastroenterology & hepatology ,Biomarkers - Abstract
Myrcludex B acts as a hepatitis B and D virus entry inhibitor blocking the sodium taurocholate cotransporting polypeptide (SLC10A1). We investigated the effects of myrcludex B on plasma bile acid disposition, tenofovir pharmacokinetics, and perpetrator characteristics on cytochrome P450 (CYP) 3A. Twelve healthy volunteers received 300 mg tenofovir disoproxil fumarate orally and 10 mg subcutaneous myrcludex B. Myrcludex B increased total plasma bile acid exposure 19.2-fold without signs of cholestasis. The rise in conjugated bile acids was up to 124-fold (taurocholic acid). Coadministration of tenofovir with myrcludex B revealed no relevant changes in tenofovir pharmacokinetics. CYP3A activity slightly but significantly decreased by 29% during combination therapy. Myrcludex B caused an asymptomatic but distinct rise in plasma bile acid concentrations and had no relevant impact on tenofovir pharmacokinetics. Changes in CYP3A activity might be due to alterations in bile acid signaling. Long-term effects of elevated bile acids will require critical evaluation.
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- 2017
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43. Expression of the Peptidase 'Fibroblast Activation Protein' on Decidual Stromal Cells Facilitating Tissue Remodeling
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Catharina Bartmann, SE Segerer, Ulrike Kämmerer, and Michael Schwab
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Vascular Endothelial Growth Factor A ,Stromal cell ,Chemokine CXCL1 ,Gestational Age ,Proinflammatory cytokine ,Andrology ,chemistry.chemical_compound ,Fibroblast activation protein, alpha ,Pregnancy ,Interleukin-1alpha ,Endopeptidases ,medicine ,Decidua ,Chemokine CCL8 ,Humans ,Chemokine CCL2 ,Tumor Necrosis Factor-alpha ,Interleukin-8 ,Serine Endopeptidases ,Proteolytic enzymes ,Obstetrics and Gynecology ,Decidualization ,Membrane Proteins ,Fibroblasts ,Immunohistochemistry ,Vascular endothelial growth factor ,medicine.anatomical_structure ,Reproductive Medicine ,chemistry ,Gelatinases ,Tumor necrosis factor alpha ,Female ,Chemokines ,Stromal Cells - Abstract
Introduction: Expression of fibroblast activation protein (FAP) has been detected in activated fibroblasts participating in injury response, fibrotic and inflammatory conditions, and tumorigenesis. Human endometrium is equally characterized by rapid tissue remodeling events due to the reproductive tasks comprising the activity of proteolytic enzymes. Objective: We therefore hypothesized that FAP-positive fibroblasts could also be involved in physiological processes requiring tissue remodeling, such as decidualization during early pregnancy. Methods/Results: The expression of FAP was analyzed by immunohistochemistry in frozen sections of decidual tissue from early pregnancy (gestational weeks: 6–12). All tissue samples clearly displayed a strong expression of FAP on the surface of stromal fibroblasts. Additionally, the percentage of FAP-positive fibroblasts freshly isolated from the decidua of the corresponding gestational weeks was calculated by applying FACS analysis. Decidual fibroblasts of different gestational weeks showed a significant decrease in FAP expression between the 6th and 7th weeks of gestation, which was followed by a steady slow reconstitution. By analyzing the expression of cytokines, chemokines, and growth factors of isolated FAP-positive decidual fibroblasts, we detected high levels of monocyte-attracting chemokines (growth-related oncogene alpha and monocyte chemoattractant protein-1 and -2), granulocyte-attracting chemokines (e.g., IL-8), proinflammatory factors (IL-1α and tumor necrosis factor alpha), and angiogenic substances (e.g., vascular endothelial growth factor and IL-8), which all promote an optimal microenvironment for implantation and growth of the conceptus. Conclusions: Our data demonstrate that the healthy early pregnancy decidua is characterized by a general occurrence of FAP-positive fibroblasts possibly participating in active tissue remodeling during implantation.
- Published
- 2019
44. Experimental Systems
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Michael Schwab
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Philosophy - Published
- 2019
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45. Futures of the Contemporary
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Michael Schwab
- Subjects
Financial economics ,media_common.quotation_subject ,Art ,Futures contract ,media_common - Published
- 2019
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46. 1880-P: The Protein-Tyrosine Phosphatase Shp1 Interacts with PPAR Gamma and Regulates Its Transcriptional Activity through Dephosphorylation of Selected Tyrosine Sites
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Vanessa P. Houde, Kerstin Bellmann, Marie-Helene Lavallee-Bourget, Amit Kumar, André Marette, Michael Schwab, Marie-Pier Forest, Nicole Beauchemin, and Halim Maaroufi
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0301 basic medicine ,chemistry.chemical_classification ,medicine.medical_specialty ,biology ,Chemistry ,Endocrinology, Diabetes and Metabolism ,Peroxisome proliferator-activated receptor ,030209 endocrinology & metabolism ,Tyrosine phosphorylation ,Protein tyrosine phosphatase ,03 medical and health sciences ,Insulin receptor ,chemistry.chemical_compound ,030104 developmental biology ,0302 clinical medicine ,Endocrinology ,Internal medicine ,Internal Medicine ,medicine ,biology.protein ,Phosphorylation ,Glucose homeostasis ,Tyrosine ,Proto-oncogene tyrosine-protein kinase Src - Abstract
Src homology region 2 domain-containing phosphatase-1 (Shp1) plays an important role in modulating insulin signaling and thereby glucose homeostasis. Our laboratory has demonstrated that despite being more prone to hepatic steatosis, mice with a liver specific Shp1 knock out (Shp1H-KO) on high-fat diet (HFD) exhibit improved fasting glycaemia, reduced insulin resistance and lower inflammation than their flox/flox littermates. Microarray analysis of HFD-fed Shp1H-KO versus Shp1fl/fl livers revealed elevated levels of peroxisome proliferator-activated receptor gamma (PPARγ), an important transcription factor controlling adipogenesis. In addition, overexpression of Shp1 decreased PPARγ activity in vitro. The aim of this study was to investigate the mechanism of regulation of PPARγ by Shp1. Molecular modeling analyses suggested that Shp1 interaction with PPARγ depends on the tyrosine phosphorylation status of PPARγ. We found, by co-immunoprecipitation, that Shp1 N-terminal SH2-domains binds to PPARγ. We confirmed PPARγ tyrosine-phosphorylation and demonstrated that this phosphorylation could be reduced by Shp1 in vitro. Using mass spectrometry, we identified 5 phosphorylated tyrosine residues in PPARγ. Mutagenesis experiments showed that PPARγ significantly lost its activity when two of these sites were selectively and independently mutated to the non-phosphorylatable phenylalanine but did not interfere with the nuclear localization of PPARγ. Additionally, we generated Shp1 knockout HepG2 cells using CRISPR-Cas9 technology. We found that expression of several PPARγ regulated transcripts was upregulated in Shp1-KO cells as compared to control cells. Altogether, we show that PPARγ is a novel substrate of Shp1. Our results reveal a fine regulation of PPARγ tyrosine phosphorylation by Shp1, which might lead to novel therapeutic approaches for treating metabolic disorders related to obesity. Disclosure A. Kumar: None. M. Lavallee-Bourget: None. M. Forest: None. M. Schwab: None. K. Bellmann: None. V. Houde: None. H. Maaroufi: None. N. Beauchemin: None. A. Marette: Advisory Panel; Self; Plexus, Valbiotis. Consultant; Self; Danone Nutricia Research.
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- 2019
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47. The Structural Determinants Accounting for the Broad Substrate Specificity of the Quorum Quenching Lactonase GcL
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Michael Schwab, Tanushree Naik, Celine Bergonzi, and Mikael Elias
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Stereochemistry ,Homoserine ,Acyl-Butyrolactones ,010402 general chemistry ,01 natural sciences ,Biochemistry ,Substrate Specificity ,chemistry.chemical_compound ,Bacterial Proteins ,Catalytic Domain ,Hydrolase ,Lactonase ,Enzyme kinetics ,Bacillaceae ,Molecular Biology ,biology ,010405 organic chemistry ,Chemistry ,Organic Chemistry ,Biofilm ,food and beverages ,Substrate (chemistry) ,biochemical phenomena, metabolism, and nutrition ,0104 chemical sciences ,Quorum sensing ,Quorum Quenching ,biology.protein ,Molecular Medicine ,Carboxylic Ester Hydrolases ,Hydrophobic and Hydrophilic Interactions ,Protein Binding - Abstract
Quorum quenching lactonases are enzymes capable of hydrolyzing lactones, including N-acyl homoserine lactones (AHLs). AHLs are molecules known as signals in bacterial communication dubbed quorum sensing. Bacterial signal disruption by lactonases was previously reported to inhibit behavior regulated by quorum sensing, such as the expression of virulence factors and the formation of biofilms. Herein, we report the enzymatic and structural characterization of a novel lactonase representative from the metallo-β-lactamase superfamily, dubbed GcL. GcL is a broad spectrum and highly proficient lactonase, with kcat /KM values in the range of 104 to 106 m-1 s-1 . Analysis of free GcL structures and in complex with AHL substrates of different acyl chain length, namely, C4-AHL and 3-oxo-C12-AHL, allowed their respective binding modes to be elucidated. Structures reveal three subsites in the binding crevice: 1) the small subsite where chemistry is performed on the lactone ring; 2) a hydrophobic ring that accommodates the amide group of AHLs and small acyl chains; and 3) the outer, hydrophilic subsite that extends to the protein surface. Unexpectedly, the absence of structural accommodation for long substrate acyl chains seems to relate to the broad substrate specificity of the enzyme.
- Published
- 2019
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48. Phosphofructokinase-P Modulates P44/42 MAPK Levels in HeLa Cells
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Patricia Zancan, Thyago Rubens Cardim Pires, Mauro Sola-Penna, Renato S. Carvalho, Michael Schwab, Jamille Mansur Albanese, and Andre Marette
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0301 basic medicine ,MAPK/ERK pathway ,Cell ,Cell Biology ,Biology ,biology.organism_classification ,Biochemistry ,3. Good health ,Cell biology ,HeLa ,03 medical and health sciences ,030104 developmental biology ,0302 clinical medicine ,medicine.anatomical_structure ,Downregulation and upregulation ,030220 oncology & carcinogenesis ,Cancer cell ,medicine ,Gene silencing ,Viability assay ,Protein kinase A ,Molecular Biology - Abstract
It is known that interfering with glycolysis leads to profound modification of cancer cell proliferation. However, energy production is not the major reason for this correlation. Here, using HeLa cells as a model for cancer, we demonstrate that phosphofructokinase-P (PFK-P), which is overexpressed in diverse types of cancer including HeLa cells, modulates expression of P44/42 mitogen-activated protein kinase (MAPK). Silencing of PFK-P did not alter HeLa cell viability or energy production, including the glycolytic rate. On the other hand, silencing of PFK-P induced the downregulation of p44/42 MAPK, augmenting the sensitivity of HeLa cells to different drugs. Conversely, overexpression of PFK-P promotes the upregulation of p44/42 MAPK, making the cells more resistant to the drugs. These results indicate that overexpression of PFK-P by cancer cells is related to activation of survival pathways via upregulation of MAPK and suggest PFK-P as a promising target for cancer therapy. J. Cell. Biochem. 118: 1216-1226, 2017. © 2016 Wiley Periodicals, Inc.
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- 2017
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49. Futures of the Contemporary : Contemporaneity, Untimeliness, and Artistic Research
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Paulo de Assis, Michael Schwab, Paulo de Assis, and Michael Schwab
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- Arts--Philosophy, Contemporary, The
- Abstract
Transdisciplinary approaches to the notions of “the contemporary” and “contemporaneity” Futures of the Contemporary explores different notions and manifestations of “the contemporary” in music, visual arts, art theory, and philosophy. In particular, the authors in this collection of essays scrutinise the role of artistic research in critical and creative expressions of contemporaneity. When distinguished from “the contemporaneous” of a given historical time, “the contemporary” becomes a crucial concept, promoting or excluding objects and practices according to their ability to diagnose previously unnoticed aspects of the present. In this sense, the contemporary gains a critical function, involving particular modes of relating to history and one's own time. Written by major experts from fields such as music performance, composition, art theory, visual arts, art history, critical studies, and philosophy, this book offers challenging perspectives on contemporary art practices, the temporality of artistic works and phenomena, and new modes of problematising the production of art and its public apprehension.Contributors: Andrew Prior (University of Plymouth), Babette Babich (Fordham University), Geoff Cox (Fine Art at Plymouth University / Aarhus University), Heiner Goebbels (Justus Liebig University), Jacob Lund (Aarhus University), Michael Schwab (Orpheus Institute), Pal Capdevila (Autonomous University of Barcelona), Paulo de Assis (Orpheus Institute), Peter Osborne (Kingston University London), Ryan Nolan (University of Plymouth), Zsuzsa Baross (Trent University)This publication is GPRC-labeled (Guaranteed Peer-Reviewed Content).
- Published
- 2019
50. Diel discharge cycles explained through viscosity fluctuations in riparian inflow
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Michael Schwab, Markus Weiler, Julian Klaus, and Laurent Pfister
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Hydrology ,geography ,geography.geographical_feature_category ,0208 environmental biotechnology ,Growing season ,02 engineering and technology ,Inflow ,Vegetation ,020801 environmental engineering ,Viscosity ,Evapotranspiration ,Environmental science ,Maxima ,Diel vertical migration ,Water Science and Technology ,Riparian zone - Abstract
Diel (also called diurnal) discharge patterns with minima in the afternoon are generally explained by the daily cycle of evapotranspiration, while maxima in the afternoon are often linked to freeze-thaw cycles. In a schistose and forested headwater catchment in Luxembourg, we observed daily discharge maxima in the afternoon, although temperatures remained persistently above zero and vegetation was still in a dormant state. We show that diel water temperature fluctuations - and therefore viscosity fluctuations - in the upper layer of the riparian zone can be an explanation for the observed daily discharge maxima in the afternoon during the dormant season. In the transition period between the dormant and the growing season, the counteracting viscosity and evapotranspiration processes cancel each other out. Subsequently, during the growing season, evapotranspiration is the dominant process guiding the diel discharge pattern; nevertheless, the viscosity effect might still be present, but invisible. We believe this finding also to be of relevance when analyzing daily fluctuations of biogeochemicals in stream water. This article is protected by copyright. All rights reserved.
- Published
- 2016
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