1
|
Firoozabadi S, Kükelhan P, Beyer A, Lehr J, Volz K. Quantitative composition determination by ADF-STEM at a low angular regime: a combination of EFSTEM and 4DSTEM. Ultramicroscopy 2022; 240:113550. [DOI: 10.1016/j.ultramic.2022.113550] [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] [Received: 01/18/2022] [Revised: 04/26/2022] [Accepted: 05/04/2022] [Indexed: 10/18/2022]
|
2
|
Firoozabadi S, Kükelhan P, Hepp T, Beyer A, Volz K. Optimization of imaging conditions for composition determination by annular dark field STEM. Ultramicroscopy 2021; 230:113387. [PMID: 34619567 DOI: 10.1016/j.ultramic.2021.113387] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2021] [Revised: 08/15/2021] [Accepted: 08/23/2021] [Indexed: 10/20/2022]
Abstract
Quantitative scanning transmission electron microscopy (STEM) allows composition determination for nanomaterials at an atomic scale. To improve the accuracy of the results obtained, optimized imaging parameters should be chosen for annular dark field imaging. In a simulation study, we investigate the influence of imaging parameters on the accuracy of the composition determination with the example of ternary III-V semiconductors. It is shown that inner and outer detector angles and semi-convergence angle can be optimized, also in dependence on specimen thickness. Both, a minimum sampling of the image and a minimum electron dose are required. These findings are applied experimentally by using a fast pixelated detector to allow free choice of detector angles.
Collapse
Affiliation(s)
- S Firoozabadi
- Materials Science Center and Faculty of Physics, Philipps-Universität Marburg, Hans-Meerweinstraße 6, Marburg, Germany
| | - P Kükelhan
- Materials Science Center and Faculty of Physics, Philipps-Universität Marburg, Hans-Meerweinstraße 6, Marburg, Germany
| | - T Hepp
- Materials Science Center and Faculty of Physics, Philipps-Universität Marburg, Hans-Meerweinstraße 6, Marburg, Germany
| | - A Beyer
- Materials Science Center and Faculty of Physics, Philipps-Universität Marburg, Hans-Meerweinstraße 6, Marburg, Germany.
| | - K Volz
- Materials Science Center and Faculty of Physics, Philipps-Universität Marburg, Hans-Meerweinstraße 6, Marburg, Germany.
| |
Collapse
|
3
|
He F, Steige KA, Kovacova V, Göbel U, Bouzid M, Keightley PD, Beyer A, de Meaux J. Cis-regulatory evolution spotlights species differences in the adaptive potential of gene expression plasticity. Nat Commun 2021; 12:3376. [PMID: 34099660 PMCID: PMC8184852 DOI: 10.1038/s41467-021-23558-2] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2020] [Accepted: 04/29/2021] [Indexed: 11/09/2022] Open
Abstract
Phenotypic plasticity is the variation in phenotype that a single genotype can produce in different environments and, as such, is an important component of individual fitness. However, whether the effect of new mutations, and hence evolution, depends on the direction of plasticity remains controversial. Here, we identify the cis-acting modifications that have reshaped gene expression in response to dehydration stress in three Arabidopsis species. Our study shows that the direction of effects of most cis-regulatory variants differentiating the response between A. thaliana and the sister species A. lyrata and A. halleri depends on the direction of pre-existing plasticity in gene expression. A comparison of the rate of cis-acting variant accumulation in each lineage indicates that the selective forces driving adaptive evolution in gene expression favors regulatory changes that magnify the stress response in A. lyrata. The evolutionary constraints measured on the amino-acid sequence of these genes support this interpretation. In contrast, regulatory changes that mitigate the plastic response to stress evolved more frequently in A. halleri. Our results demonstrate that pre-existing plasticity may be a stepping stone for adaptation, but its selective remodeling differs between lineages.
Collapse
Affiliation(s)
- F He
- CEPLAS, University of Cologne, Cologne, Germany
| | - K A Steige
- CEPLAS, University of Cologne, Cologne, Germany
| | - V Kovacova
- CECAD, University of Cologne, Cologne, Germany
| | - U Göbel
- CEPLAS, University of Cologne, Cologne, Germany
| | - M Bouzid
- CEPLAS, University of Cologne, Cologne, Germany
| | - P D Keightley
- Institute of Evolutionary Biology, University of Edinburgh, Edinburgh, UK
| | - A Beyer
- CEPLAS, University of Cologne, Cologne, Germany
| | - J de Meaux
- CEPLAS, University of Cologne, Cologne, Germany.
| |
Collapse
|
4
|
Hsu R, Brunet L, Fusco J, Beyer A, Prajapati G, Wyatt C, Wohlfeiler M, Fusco G. Risk of chronic kidney disease in people living with HIV by tenofovir disoproxil fumarate (TDF) use and baseline D:A:D chronic kidney disease risk score. HIV Med 2021; 22:325-333. [PMID: 33247876 PMCID: PMC8246783 DOI: 10.1111/hiv.13019] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/21/2020] [Indexed: 12/14/2022]
Abstract
OBJECTIVES To assess the risk of chronic kidney disease (CKD) associated with tenofovir disoproxil fumarate (TDF) use by baseline D:A:D CKD risk score. METHODS Adult antiretroviral therapy (ART)-naïve people living with HIV (PLWH) initiating treatment, with estimated glomerular filtration rate (eGFR) ≥ 60 mL/min/1.73 m2 , were identified in the OPERA cohort. CKD was defined as two or more consecutive eGFR < 60 mL/min/1.73 m2 , > 90 days apart. Associations between TDF use, baseline D:A:D CKD risk and incident CKD were assessed with incidence rates (IRs; Poisson regression) and adjusted pooled logistic regression. The impact of pharmacoenhancers on the observed association between TDF and CKD was also evaluated. RESULTS Of 9802 PLWH included, 6222 initiated TDF and 3580 did not (76% and 79% low D:A:D CKD risk, respectively). Overall, 125 CKD events occurred over 24 382 person-years of follow-up. Within strata of D:A:D CKD risk score, IRs were similar across TDF exposure, with high baseline CKD risk associated with highest incidence. Compared with the low-risk group without TDF, there was no statistical difference in odds of incident CKD in the low-risk group with TDF (adjusted odds ratio = 0.55, 95% confidence interval: 0.19-1.54). Odds of incident CKD did not differ statistically significantly by pharmacoenhancer exposure, with or without TDF. CONCLUSIONS In this large cohort of ART-naïve PLWH, incident CKD following ART initiation was infrequent and strongly associated with baseline CKD risk. TDF-containing regimens did not increase the odds of CKD in those with a low baseline D:A:D CKD risk, the largest group of ART-naïve PLWH, and may remain a viable treatment option in appropriate settings.
Collapse
Affiliation(s)
- R Hsu
- NYU Langone Health CenterNew YorkNYUSA
- AIDS Healthcare FoundationNew YorkNYUSA
| | | | | | - A Beyer
- Merck & Co., Inc.KenilworthNJUSA
| | | | | | | | | |
Collapse
|
5
|
Mannix S, Beyer A, Strand V, Hanrahan L, Abél C, Flamion B, Hareendran A. AB1249 ASSESSMENT OF FATIGUE IN ADULTS WITH MODERATE-TO-SEVERE SYSTEMIC LUPUS ERYTHEMATOSUS (SLE): A QUALITATIVE STUDY TO EXPLORE WHAT PATIENTS FEEL SHOULD BE MEASURED IN CLINICAL TRIALS. Ann Rheum Dis 2020. [DOI: 10.1136/annrheumdis-2020-eular.3849] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
Background:Fatigue is one of the most common symptoms reported by patients with systemic lupus erythematosus (SLE)—it is responsible for considerable loss of work time and greatly impaired quality of life. The Functional Assessment of Chronic Illness Therapy-Fatigue (FACIT-F) has been used to assess fatigue in SLE clinical trials1; however, assessment of the content validity of the FACIT-F in adults with SLE suggested that closer evaluation may be warranted.2Objectives:This qualitative study aimed to understand SLE patients’ experience of fatigue and assess the content validity of the FACIT-F.Methods:The evaluation was informed by literature and guided by a project steering committee (PSC; patient advocate, clinical expert, outcomes measure expert). The institutional review board-approved study involved focus groups (Round 1) and cognitive interviews (Round 2) with adults with moderate-to-severely active SLE. All participants provided written informed consent. Round 1 included three focus groups to understand the disease and fatigue-related concepts that were most important to patients; participants also provided high-level feedback on the FACIT-F. Round 2 included 13 one-on-one cognitive interviews on the relevance of content, clarity, and comprehensiveness of the FACIT-F. Interviews were audio-recorded and transcribed and a content analysis was completed. The PSC reviewed results and contributed to decision-making. Specific focus was on determining patient understanding of the FACIT-F, comprehensiveness, and any gaps in concept coverage to evaluate fatigue in the context of a clinical trial.Results:Twenty-eight patients with moderate-to-severely active SLE participated; they were mostly female (n=27), had a mean age of 45.5 ± 12.1 years (range: 18–75), and 23 (82%) had moderate and five (18%) severely active SLE. All participants were receiving SLE treatment, and most (n=23, 82%) reported fatigue among their top three most important SLE-related symptoms. Fatigue was described as having a profound impact on daily life, including ability to perform chores and work-related activities, maintain personal hygiene, exercise, and participate in hobbies. Study participants reported the FACIT-F covered concepts most relevant to their fatigue experience. Participants were able to understand the FACIT-F instructions, items, and response options and felt the recall period of seven days was appropriate.Conclusion:Fatigue was one of the most important symptoms, having a significant impact on adults with moderate-to-severely active SLE, limiting their ability to perform necessary or desired activities. The FACIT-F was found to be an appropriate measure for the assessment of fatigue in this sample.3Evidence of the content validity of the FACIT-F in adults with SLE was confirmed for use to support endpoints in the Cenerimod Assessing S1P1Receptor Modulation in SLE (CARE) clinical trial.References:[1]Izadi Z, Gandrup J, Katz PP, Yazdany J. Patient-reported outcome measures for use in clinical trials of SLE: a review. Lupus Sci Med. 2018;5(1):e000279.[2]Kosinski M, Gajria K, Fernandes A, Cella D. Qualitative validation of the FACIT-Fatigue scale in systemic lupus erythematosus. Lupus. 2013;22(5):422-430.[3]Mannix S, Beyer A, Strand V, Hanrahan L, Abel C, Flamion B, Hareendran A. Assessment of Fatigue in Adults with Moderate to Severe Systemic Lupus Erythematosus (SLE): A Qualitative Study to Explore What Patients Feel Should Be Measured in Clinical Trials [abstract]. Arthritis Rheumatol. 2019; 71 (suppl 10).Acknowledgments:We thank Dr. David Cella, developer of the FACIT-F, for his time discussing the measure, interim findings, and PSC feedback; the site staff for patient recruitment; Andrea Schulz and Rodolfo Matos, who conducted interviews.Disclosure of Interests:Sally Mannix Employee of: Evidera, Andrea Beyer Employee of: Idorsia Pharmaceuticals, Vibeke Strand Consultant of: AbbVie, Amgen, Biogen, Celltrion, Consortium of Rheumatology Researchers of North America, Crescendo Bioscience, Eli Lilly, Genentech/Roche, GlaxoSmithKline, Hospira, Janssen, Merck, Novartis, Pfizer, Regeneron Pharmaceuticals, Inc., Sanofi, UCB, Leslie Hanrahan: None declared, Cristina Abél Employee of: Evidera, Bruno Flamion Shareholder of: Idorsia Pharmaceuticals, Employee of: Idorsia Pharmaceuticals, Asha Hareendran Employee of: Evidera
Collapse
|
6
|
Mills AM, Schulman KL, Fusco JS, Brunet L, Hsu R, Beyer A, Prajapati G, Mounzer K, Fusco GP. Validation of the Data Collection on Adverse Events of Anti-HIV Drugs (D:A:D) chronic kidney disease risk score in HIV-infected patients in the USA. HIV Med 2020; 21:299-308. [PMID: 31985887 PMCID: PMC7217174 DOI: 10.1111/hiv.12826] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [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] [Accepted: 10/29/2019] [Indexed: 12/30/2022]
Abstract
Objectives The aim of the study was to assess the validity of an easy‐to‐calculate chronic kidney disease (CKD) risk score developed by the Data Collection on Adverse Events of Anti‐HIV Drugs (D:A:D) group in a longitudinal observational study of people living with HIV (PLWH) in the USA. Methods PLWH (2002–2016) without prior exposure to potentially nephrotoxic antiretroviral agents and with at least three estimated glomerular filtration rate (eGFR) test results were identified in the Observational Pharmaco‐Epidemiology Research and Analysis (OPERA®) cohort. Three samples were drawn independently using the same eligibility criteria but each using a different eGFR equation, specifically the Cockcroft–Gault (C‐G), Modification of Diet in Renal Disease (MDRD) or Chronic Kidney Disease Epidemiology Collaboration (CKD‐EPI) eGFR estimation method. Full and short D:A:D risk scores were applied. CKD was defined as a confirmed decrease in eGFR to < 60 mL/min/1.73 m2 (stages 3–5). Poisson models estimated the association between CKD incidence and a one‐point increase in the continuous risk score. The incidence rate ratio (IRR), adjusted IRR (aIRR), and Harrell's discrimination statistic were used to assess validity. Results There were 19 444, 22 727 and 22 748 PLWH in the OPERA C‐G, CKD‐EPI and MDRD samples, respectively. The median (minimum–maximum) follow‐up duration was 6.1 (0.3–9.1) years in the D:A:D cohort and ranged from 3.2 to 3.5 (0.2–15.5) years in the OPERA validation samples. The observation time for the majority of PLWH in the D:A:D cohort began prior to 2006, in stark contrast to the OPERA validation samples, where the majority of PLWH were observed after 2011. The CKD incidence ranged from 7.3 per 1000 person‐years [95% confidence interval (CI) 6.8, 7.9 per 1000 person‐years] in OPERA C‐G to 11.0 (95% CI 10.4, 11.6 per 1000 person‐years) in OPERA MDRD. In OPERA samples, IRRs by risk group and adjusted IRRs (full risk score) were similar to those in the D:A:D derivation cohort (adjusted IRR 1.3; 95% CI 1.3, 1.3). Harrell's c‐statistic ranged from 0.87 to 0.92 in the OPERA samples, comparable to that in the derivation cohort (0.92). Results for short scores were similar. Conclusions The findings support the validity of the D:A:D risk scoring method for assessing CKD (stages 3–5) probability in an exclusively USA‐based sample regardless of eGFR method.
Collapse
Affiliation(s)
- A M Mills
- Men's Health Foundation, Los Angeles, CA, USA
| | | | | | - L Brunet
- Epividian, Inc., Durham, NC, USA
| | - R Hsu
- NYU Langone Health, New York, NY, USA.,AIDS Healthcare Foundation, New York, NY, USA
| | - A Beyer
- Merck & Co., Inc., Kenilworth, NJ, USA
| | | | - K Mounzer
- Philadephia Fight, Philadelphia, PA, USA
| | | |
Collapse
|
7
|
Kükelhan P, Hepp T, Firoozabadi S, Beyer A, Volz K. Composition determination for quaternary III-V semiconductors by aberration-corrected STEM. Ultramicroscopy 2019; 206:112814. [PMID: 31310886 DOI: 10.1016/j.ultramic.2019.112814] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2019] [Revised: 07/04/2019] [Accepted: 07/07/2019] [Indexed: 10/26/2022]
Abstract
Quantitative scanning transmission electron microscopy (STEM) is a powerful tool for the characterization of nano-materials. Absolute composition determination for ternary III-V semiconductors by direct comparison of experiment and simulation is well established. Here, we show a method to determine the composition of quaternary III-V semiconductors with two elements on each sub lattice from the intensities of one STEM image. As an example, this is applied to (GaIn)(AsBi). The feasibility of the method is shown in a simulation study that also explores the influence of detector angles and specimen thickness. Additionally, the method is applied to an experimental STEM image of a (GaIn)(AsBi) quantum well grown by metal organic vapour phase epitaxy. The obtained concentrations are in good agreement with X-ray diffraction and photoluminescence results.
Collapse
Affiliation(s)
- P Kükelhan
- Materials Science Centre and Faculty of Physics, Philipps University Marburg, Hans-Meerwein-Straße 6, Marburg, Germany
| | - T Hepp
- Materials Science Centre and Faculty of Physics, Philipps University Marburg, Hans-Meerwein-Straße 6, Marburg, Germany
| | - S Firoozabadi
- Materials Science Centre and Faculty of Physics, Philipps University Marburg, Hans-Meerwein-Straße 6, Marburg, Germany
| | - A Beyer
- Materials Science Centre and Faculty of Physics, Philipps University Marburg, Hans-Meerwein-Straße 6, Marburg, Germany.
| | - K Volz
- Materials Science Centre and Faculty of Physics, Philipps University Marburg, Hans-Meerwein-Straße 6, Marburg, Germany
| |
Collapse
|
8
|
Farin P, Marquardt M, Martyanov W, Belz J, Beyer A, Volz K, Lenz A. Three-dimensional structure of antiphase domains in GaP on Si(0 0 1). J Phys Condens Matter 2019; 31:144001. [PMID: 30625435 DOI: 10.1088/1361-648x/aafcfb] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Antiphase domains are three-dimensional crystal defects commonly arising at the interface of III-V semiconductors and Si. While control over their formation has been achieved, the geometry of the antiphase domain itself that is separated from the mainphase of the crystal by the so-called antiphase boundary, has not yet been fully understood. In this work, we first investigate the interface between GaP and Si itself by cross-sectional scanning tunneling microscopy (XSTM) to reveal possible intermixing within an 8 monolayers wide region. Furthermore, we present an extensive analysis combining transmission electron microscopy and XSTM to elucidate the shape of antiphase domains in GaP. To create a true-to-scale, three-dimensional model of an antiphase domain, firstly, plan-view transmission electron microscopy images are drawn on. Subsequently, the progression of many antiphase boundaries through the GaP crystal as viewed from the (1 1 0) and (1 [Formula: see text] 0) cleavage planes is analyzed all the way down to the atomic level by means of XSTM. This enables a detailed analysis of the shape and physical dimensions of the antiphase domains. A typical measured extension in growth directions is found to be a maximum of 60 nm and the maximum measured extension of the base plane in [[Formula: see text] 1 0] and [1 1 0] directions is about 160 nm and 50 nm, respectively. They appear as pyramids with anisotropic base planes whose side facets kink many times.
Collapse
Affiliation(s)
- P Farin
- Institut für Festkörperphysik, Technische Universität Berlin, Hardenbergstraße 36, D-10623 Berlin, Germany
| | | | | | | | | | | | | |
Collapse
|
9
|
Brixius K, Beyer A, Mette G, Güdde J, Dürr M, Stolz W, Volz K, Höfer U. Second-harmonic generation as a probe for structural and electronic properties of buried GaP/Si(0 0 1) interfaces. J Phys Condens Matter 2018; 30:484001. [PMID: 30406767 DOI: 10.1088/1361-648x/aae85b] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Optical second-harmonic generation is demonstrated to be a sensitive probe of the buried interface between the lattice-matched semiconductors gallium phosphide and silicon with (0 0 1) orientation. Ex situ rotational anisotropy measurements on GaP/Si heterostructures show a strong isotropic component of the second-harmonic response not present for pure Si(0 0 1) or GaP(0 0 1). The strength of the overlaying anisotropic response directly correlates with the quality of the interface as determined by atomically resolved scanning transmission electron microscopy. Systematic comparison of samples fabricated under different growth conditions in metal-organic vapor phase epitaxy reveals that the anisotropy for different polarization combinations can be used as a selective fingerprint for the occurrence of anti-phase domains and twins. This all-optical technique can be applied as an in situ and non-invasive monitor even during growth.
Collapse
Affiliation(s)
- K Brixius
- Fachbereich Physik und Zentrum für Materialwissenschaften, Philipps-Universität Marburg, 35032 Marburg, Germany
| | | | | | | | | | | | | | | |
Collapse
|
10
|
Wurm S, Beyer A, Wolff JK, Spuling SM. SOCIAL CHANGE IN SELF-PERCEPTIONS OF AGING ACROSS TWO DECADES. Innov Aging 2018. [DOI: 10.1093/geroni/igy023.3096] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Affiliation(s)
- S Wurm
- Friedrich-Alexander-University Erlangen-Nürnberg, Nürnberg, Bayern, Germany
| | - A Beyer
- Friedrich-Alexander-University Erlangen-Nürnberg (FAU), Nürnberg, Germany
| | - J K Wolff
- Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), Nürnberg, Germany; IGES Institute, Berlin, Germany
| | - S M Spuling
- German Centre of Gerontology, Berlin, Germany
| |
Collapse
|
11
|
Beyer A. Continuous Improvement 4.0 Prozessoptimierung im Zeitalter der Digitalisierung. CHEM-ING-TECH 2018. [DOI: 10.1002/cite.201855356] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- A. Beyer
- TrendMiner; Customer Success; Kempische Steenweg 297 3500 Hasselt Belgien
| |
Collapse
|
12
|
Abstract
Liquid phase exfoliation (LPE) of layered compounds towards few- or monolayers has been established as one of the prime methods in the growing field of 2D material research. Here, we present first steps towards an effective LPE of bismuth(iii) iodide, a semiconductor with potential as a photovoltaic absorber material. We highlight guidelines in the choice of exfoliating solvent, which differ significantly from those used with transition metal dichalcogenides or graphene. We also present first evidence of successful few-layer formation from spectroscopic, electron microscopy and electron diffraction investigations.
Collapse
Affiliation(s)
- N Heidary
- Department of Chemistry and Material Sciences Center, Philipps-Universität Marburg, Hans-Meerwein-Straße, 35043 Marburg, Germany.
| | | | | | | |
Collapse
|
13
|
Wurm S, Beyer A, Wolff J. SOCIAL CHANGE OF VIEWS ON AGING OVER TWO DECADES: ARE THEY GETTING MORE POSITIVE? Innov Aging 2017. [DOI: 10.1093/geroni/igx004.4894] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- S. Wurm
- Friedrich-Alexander-University Erlangen-Nuremberg (FAU), Nuremberg, Germany,
| | - A. Beyer
- Friedrich-Alexander-University Erlangen-Nuremberg (FAU), Nuremberg, Germany,
| | - J.K. Wolff
- German Centre of Gerontology, Berlin, Germany
| |
Collapse
|
14
|
Toro-Tapia G, Villaseca S, Leal JI, Beyer A, Fuentealba J, Torrejón M. Xenopus as a model organism to study heterotrimeric G-protein pathway during collective cell migration of neural crest. Genesis 2017; 55. [PMID: 28095644 DOI: 10.1002/dvg.23008] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [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: 11/18/2016] [Revised: 11/22/2016] [Accepted: 11/24/2016] [Indexed: 01/03/2023]
Abstract
Collective cell migration is essential in many fundamental aspects of normal development, like morphogenesis, organ formation, wound healing, and immune responses, as well as in the etiology of severe pathologies, like cancer metastasis. In spite of the huge amount of data accumulated on cell migration, such a complex process involves many molecular actors, some of which still remain to be functionally characterized. One of these signals is the heterotrimeric G-protein pathway that has been studied mainly in gastrulation movements. Recently we have reported that Ric-8A, a GEF for Gα proteins, plays an important role in neural crest migration in Xenopus development. Xenopus neural crest cells, a highly migratory embryonic cell population induced at the border of the neural plate that migrates extensively in order to differentiate in other tissues during development, have become a good model to understand the dynamics that regulate cell migration. In this review, we aim to provide sufficient evidence supporting how useful Xenopus model with its different tools, such as explants and transplants, paired with improved in vivo imaging techniques, will allow us to tackle the multiple signaling mechanisms involved in neural crest cell migration.
Collapse
Affiliation(s)
- G Toro-Tapia
- Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias Biológicas, Universidad de Concepción, Casilla 160-C, Concepción, Chile
| | - S Villaseca
- Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias Biológicas, Universidad de Concepción, Casilla 160-C, Concepción, Chile
| | - J I Leal
- Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias Biológicas, Universidad de Concepción, Casilla 160-C, Concepción, Chile
| | - A Beyer
- Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias Biológicas, Universidad de Concepción, Casilla 160-C, Concepción, Chile
| | - J Fuentealba
- Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias Biológicas, Universidad de Concepción, Casilla 160-C, Concepción, Chile
| | - M Torrejón
- Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias Biológicas, Universidad de Concepción, Casilla 160-C, Concepción, Chile
| |
Collapse
|
15
|
de Gregorio N, Beyer A, Friedl TWP, Mian E, Schramm A, Blankenstein T, Rempen A, Mahner S, Janni W, Ebner F. Vergleich von Rezidivraten und Überleben nach Sentinel-Lymphknotenbiopsie oder inguinaler Lymphknotenentfernung bei Patientinnen mit nodal-negativem Vulvakarzinom. Geburtshilfe Frauenheilkd 2016. [DOI: 10.1055/s-0036-1593255] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
|
16
|
Beyer A, Maisenbacher L, Matveev A, Pohl R, Khabarova K, Chang Y, Grinin A, Lamour T, Shi T, Yost DC, Udem T, Hänsch TW, Kolachevsky N. Active fiber-based retroreflector providing phase-retracing anti-parallel laser beams for precision spectroscopy. Opt Express 2016; 24:17470-17485. [PMID: 27464193 DOI: 10.1364/oe.24.017470] [Citation(s) in RCA: 3] [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: 06/06/2023]
Abstract
We present an active fiber-based retroreflector providing high quality phase-retracing anti-parallel Gaussian laser beams for precision spectroscopy of Doppler sensitive transitions. Our design is well-suited for a number of applications where implementing optical cavities is technically challenging and corner cubes fail to match the demanded requirements, most importantly retracing wavefronts and preservation of the laser polarization. To illustrate the performance of the system, we use it for spectroscopy of the 2S-4P transition in atomic hydrogen and demonstrate an average suppression of the first order Doppler shift to 4 parts in 106 of the full collinear shift. This high degree of cancellation combined with our cryogenic source of hydrogen atoms in the metastable 2S state is sufficient to enable determinations of the Rydberg constant and the proton charge radius with competitive uncertainties. Advantages over the usual Doppler cancellation based on corner cube type retroreflectors are discussed as well as an alternative method using a high finesse cavity.
Collapse
|
17
|
Wischnewski N, Zuschneid I, Beyer A. Medizinische Versorgung von Flüchtlingen in Berlin am Beispiel eines Bezirks. Gesundheitswesen 2016. [DOI: 10.1055/s-0036-1578860] [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]
|
18
|
Cording L, Boettcher A, Schattschneider R, Beyer A, Busch S. Fachärztinnen und -ärzte an der Schnittstelle zwischen medizinischen und nicht-medizinischen Versorgungssystemen. Gesundheitswesen 2015. [DOI: 10.1055/s-0035-1562974] [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: 10/23/2022]
|
19
|
Boettcher A, Beyer A, Schattenschneider R, Busch S. Die Netzwerkanalyse in der Quartiersentwicklung – Evaluation des „Projektforum Lohbrügge“ als regionales, themenzentriertes Demenznetzwerk. Gesundheitswesen 2015. [DOI: 10.1055/s-0035-1563111] [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: 10/23/2022]
|
20
|
Hockenberry J, Zinkevitch N, Beyer A, Gutterman D. Acute and Chronic Inhibition of NOS Causes a Switch in Vasodilator Mechanism from Nitric Oxide to Hydrogen Peroxide in the Human Microcirculation. FASEB J 2015. [DOI: 10.1096/fasebj.29.1_supplement.794.2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- J. Hockenberry
- Dept. of MedicineMCW MKEWIUnited States
- CVRC MCW MKEWIUnited States
| | - N. Zinkevitch
- Dept. of MedicineMCW MKEWIUnited States
- CVRC MCW MKEWIUnited States
| | - A Beyer
- Dept. of MedicineMCW MKEWIUnited States
- CVRC MCW MKEWIUnited States
| | - D. Gutterman
- Dept. of MedicineMCW MKEWIUnited States
- CVRC MCW MKEWIUnited States
| |
Collapse
|
21
|
Kinder S, Ossig C, Wienecke M, Beyer A, von der Hagen M, Storch A, Smitka M. Novel frameshift mutation in the CACNA1A gene causing a mixed phenotype of episodic ataxia and familiar hemiplegic migraine. Eur J Paediatr Neurol 2015; 19:72-4. [PMID: 25468264 DOI: 10.1016/j.ejpn.2014.10.005] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/22/2014] [Revised: 10/18/2014] [Accepted: 10/24/2014] [Indexed: 11/19/2022]
Abstract
Episodic ataxia type 2 (EA2, MIM#108500) is the most common form of EA and an autosomal-dominant inherited disorder characterized by paroxysmal episodes of ataxia. The disease causative gene CACNA1A encodes for the alpha 1A subunit of the voltage-gated P/Q-type calcium channel. We report on a family with a novel mutation in the CACNA1A gene. The clinical symptoms within the family varied from the typical clinical presentation of EA2 with dysarthria, gait ataxia and oculomotor symptoms to migraine and dystonia. A novel nonsense mutation of the CACNA1A gene was identified in all affected family members and is most likely the disease causing molecular defect. The pharmacological treatment with acetazolamide (AAA) was successful in three family members so far. Treatment with AAA led to a reduction of migraine attacks and an improvement of the dystonia. This relationship confirmed the hypothesis that this novel mutation results in a heterogeneous phenotype and confutes the coincidence with common migraine. Dystonia is potentially included as a further part of the phenotype spectrum of CACNA1A gene mutations.
Collapse
Affiliation(s)
- S Kinder
- Abteilung Neuropädiatrie, Medizinische Fakultät Carl Gustav Carus, Technische Universität Dresden, Germany.
| | - C Ossig
- Klinik für Neurologie, Medizinische Fakultät Carl Gustav Carus, Technische Universität Dresden, Germany
| | - M Wienecke
- Klinik für Neurologie, Medizinische Fakultät Carl Gustav Carus, Technische Universität Dresden, Germany
| | - A Beyer
- Institut für Klinische Genetik, Medizinische Fakultät Carl Gustav Carus, Technische Universität Dresden, Germany
| | - M von der Hagen
- Abteilung Neuropädiatrie, Medizinische Fakultät Carl Gustav Carus, Technische Universität Dresden, Germany
| | - A Storch
- Klinik für Neurologie, Medizinische Fakultät Carl Gustav Carus, Technische Universität Dresden, Germany
| | - M Smitka
- Abteilung Neuropädiatrie, Medizinische Fakultät Carl Gustav Carus, Technische Universität Dresden, Germany
| |
Collapse
|
22
|
Abstract
In situ emission and absorption FTIR methods were employed to characterize the spatially resolved structure of binary Co–Cu oxides for low-temperature oxidation of CO and propene. Co–Cu oxide catalysts were controllably synthesized by pulsed-spray evaporation chemical vapor deposition. XRD, FTIR, XPS, UV-vis and helium ion microscopy (HIM) were employed to characterize the as-prepared thin films in terms of structure, composition, optical and thermal properties as well as morphology. In situ emission FTIR spectroscopy indicates that Co3O4, CuCo2O4 and CuO are thermally stable at 650, 655 and 450 °C, respectively. The catalytic tests with absorption FTIR display that the involvement of Co–Cu oxides can initiate CO and C3H6 oxidation at lower temperatures. The results indicate that in situ emission and absorption FTIR are useful techniques to explore the thermal properties and catalytic performance of functional materials, allowing many potential applications in tailoring their temporally and spatially resolved structure-property relationships.
Collapse
Affiliation(s)
- Z. Y. Tian
- Institute of Engineering Thermophysics
- Chinese Academy of Sciences
- Beijing 100190
- China
- Department of Chemistry
| | - H. Vieker
- Department of Physics
- Bielefeld University
- Universitätsstraβe. 25
- D-33615 Bielefeld
- Germany
| | | | - A. Beyer
- Department of Physics
- Bielefeld University
- Universitätsstraβe. 25
- D-33615 Bielefeld
- Germany
| |
Collapse
|
23
|
Schukfeh MI, Storm K, Hansen A, Thelander C, Hinze P, Beyer A, Weimann T, Samuelson L, Tornow M. Formation of nanogaps in InAs nanowires by selectively etching embedded InP segments. Nanotechnology 2014; 25:465306. [PMID: 25360747 DOI: 10.1088/0957-4484/25/46/465306] [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] [Indexed: 06/04/2023]
Abstract
We present a method to fabricate nanometer scale gaps within InAs nanowires by selectively etching InAs/InP heterostructure nanowires. We used vapor-liquid-solid grown InAs nanowires with embedded InP segments of 10-60 nm length and developed an etching recipe to selectively remove the InP segment. A photo-assisted wet etching process in a mixture of acetic acid and hydrobromic acid gave high selectivity, with accurate removal of InP segments down to 20 nm, leaving the InAs wire largely unattacked, as verified using scanning electron and transmission electron microscopy. The obtained nanogaps in InAs wires have potential as semiconducting electrodes to investigate electronic transport in nanoscale objects. We demonstrate this functionality by dielectrophoretically trapping 30 nm diameter gold nanoparticles into the gap.
Collapse
Affiliation(s)
- M I Schukfeh
- Institut für Halbleitertechnik, Technische Universität Braunschweig, Germany
| | | | | | | | | | | | | | | | | |
Collapse
|
24
|
Schrader I, Wittig L, Richter K, Vieker H, Beyer A, Gölzhäuser A, Hartwig A, Swiderek P. Formation and structure of copper(II) oxalate layers on carboxy-terminated self-assembled monolayers. Langmuir 2014; 30:11945-11954. [PMID: 25225717 DOI: 10.1021/la5026312] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Copper(II) oxalate was grown on carboxy-terminated self-assembled monolayers using a step-by-step approach by dipping the surfaces alternately in ethanolic solutions of copper(II) acetate and oxalic acid with intermediate thorough rinsing steps. The deposition was monitored by reflection absorption infrared spectroscopy (RAIRS), a quartz microbalance with dissipation measurement (QCM-D), scanning electron microscopy (SEM), and helium ion microscopy (HIM). Amounts of material corresponding to a coverage of 75% of a monolayer are deposited in each dipping step in copper(II) acetate solution while deposition of oxalic acid produces a viscoelastic layer that is partially removed by rinsing. This points toward initial aggregation but acid not bound to Cu(2+) ions as oxalate ions is removed by the rinsing steps. RAIRS further indicates that the material grows as copper(II) oxalate ribbons similar to the crystal structure but with ribbons oriented roughly parallel to the surface. SEM and HIM give evidence of the formation of needle-shaped structures which are a possible explanation for the viscoelastic behavior of the layer.
Collapse
Affiliation(s)
- I Schrader
- Institute of Applied and Physical Chemistry, University of Bremen , Fachbereich 2 (Chemie/Biologie), Leobener Straße/NW 2, Postfach 330440, D-28334 Bremen, Germany
| | | | | | | | | | | | | | | |
Collapse
|
25
|
Mountapmbeme Kouotou P, Vieker H, Tian ZY, Tchoua Ngamou PH, El Kasmi A, Beyer A, Gölzhäuser A, Kohse-Höinghaus K. Structure–activity relation of spinel-type Co–Fe oxides for low-temperature CO oxidation. Catal Sci Technol 2014. [DOI: 10.1039/c4cy00463a] [Citation(s) in RCA: 72] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
|
26
|
Beyer A, Parthey CG, Kolachevsky N, Alnis J, Khabarova K, Pohl R, Peters E, Yost DC, Matveev A, Predehl K, Droste S, Wilken T, Holzwarth R, Hänsch TW, Abgrall M, Rovera D, Salomon C, Laurent P, Udem T. Precision Spectroscopy of Atomic Hydrogen. ACTA ACUST UNITED AC 2013. [DOI: 10.1088/1742-6596/467/1/012003] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
|
27
|
van Dorp WF, Beyer A, Mainka M, Gölzhäuser A, Hansen TW, Wagner JB, Hagen CW, De Hosson JTM. Focused electron beam induced processing and the effect of substrate thickness revisited. Nanotechnology 2013; 24:345301. [PMID: 23899908 DOI: 10.1088/0957-4484/24/34/345301] [Citation(s) in RCA: 4] [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: 05/28/2023]
Abstract
The current understanding in the study of focused electron beam induced processing (FEBIP) is that the growth of a deposit is mainly the result of secondary electrons (SEs). This suggests that the growth rate for FEBIP is affected by the SE emission from the support. Our experiments, with membranes thinner than the SE escape depth, confirm this hypothesis. We used membranes of 1.4 and 4.3 nm amorphous carbon as supports. At the very early stage, the growth is support-dominated and the growth rate on a 4.3 nm thick membrane is three times higher than on a 1.4 nm thick membrane. This is consistent with Monte Carlo simulations for SE emission. The results suggest that SEs are dominant in the dissociation of W(CO)6 on thin membranes. The best agreement between simulations and experiment is obtained for SEs with energies between 3 and 6 eV.With this work we revisit earlier experiments, working at a precursor pressure 20 times lower than previously. Then, despite using membranes thinner than the SE escape depth, we did not see an effect on the experimental growth rate. We explain our current results by the fact that very early in the process, the growth becomes dominated by the growing deposit itself.
Collapse
Affiliation(s)
- W F van Dorp
- Materials Science, Zernike Institute for Advanced Materials, University of Groningen, Nijenborg 4, 9747 AG Groningen, The Netherlands.
| | | | | | | | | | | | | | | |
Collapse
|
28
|
Beyer A, John U, Kastirke N, Sannemann J, Hannöver W, Meyer C, Ulbricht S. [The home environment of families with children as address for a public health action for reduction of tobacco smoke]. Gesundheitswesen 2012; 75:77-81. [PMID: 23073981 DOI: 10.1055/s-0032-1311625] [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: 10/27/2022]
Abstract
AIM There is limited research about the acceptance of population-based prevention activities, offered systematically and directly at home. Screening data about smoking behaviour in families with children younger than 3 years were used. We examined associations between family variables (education, employment, number of children in the household), the "proportion of persons on social welfare" (PPSW) in the population aged 15-65 years and the following dependent variables: participation rate in a systematic screening, proportion of smokers within the sample of screened families and participation rate in counselling. METHODS For postal and personal contacts reporting data of children aged < 3 years, resident in Stralsund (due date 01.06.2008, N=1 298) were used. A total number of 827 families participated in the screening. The counselling was offered if at least 1 adult had smoked at least 1 cigarette per day in the last 4 weeks. Associations between family variables, PPSW and dependent variables were analysed using multilevel statistics. RESULTS The higher the PPSP the lower is the probability for participation in the screening (odds ratio=0.982; 95% confidence interval=0.970-0.996). There was at least one adult smoker in 425 (51.4%) of these 827 families participating in the screening. The counselling was offered in 425 families, whereby 65.9% (280) participated. There was no association between family variables, PPSW and participation in the counselling. CONCLUSION Differences in participation in the screening procedure are low: a high proportion of families in districts with a high PPSW took part. Even in districts with a PPSW rate of more than 30%, 71.3% of the families were successfully contacted. There is the recommendation to offer prevention measures in social< deprived city areas in a more proactive way considering the association between the prevalence of smoking in families and the proportion of PPSW.
Collapse
Affiliation(s)
- A Beyer
- Institut für Epidemiologie und Sozialmedizin, Universitätsmedizin Greifswald.
| | | | | | | | | | | | | |
Collapse
|
29
|
Greiner JFW, Hauser S, Widera D, Müller J, Qunneis F, Zander C, Martin I, Mallah J, Schuetzmann D, Prante C, Schwarze H, Prohaska W, Beyer A, Rott K, Hütten A, Gölzhäuser A, Sudhoff H, Kaltschmidt C, Kaltschmidt B. Efficient animal-serum free 3D cultivation method for adult human neural crest-derived stem cell therapeutics. Eur Cell Mater 2011; 22:403-19. [PMID: 22179938 DOI: 10.22203/ecm.v022a30] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
Due to their broad differentiation potential and their persistence into adulthood, human neural crest-derived stem cells (NCSCs) harbour great potential for autologous cellular therapies, which include the treatment of neurodegenerative diseases and replacement of complex tissues containing various cell types, as in the case of musculoskeletal injuries. The use of serum-free approaches often results in insufficient proliferation of stem cells and foetal calf serum implicates the use of xenogenic medium components. Thus, there is much need for alternative cultivation strategies. In this study we describe for the first time a novel, human blood plasma based semi-solid medium for cultivation of human NCSCs. We cultivated human neural crest-derived inferior turbinate stem cells (ITSCs) within a blood plasma matrix, where they revealed higher proliferation rates compared to a standard serum-free approach. Three-dimensionality of the matrix was investigated using helium ion microscopy. ITSCs grew within the matrix as revealed by laser scanning microscopy. Genetic stability and maintenance of stemness characteristics were assured in 3D cultivated ITSCs, as demonstrated by unchanged expression profile and the capability for self-renewal. ITSCs pre-cultivated in the 3D matrix differentiated efficiently into ectodermal and mesodermal cell types, particularly including osteogenic cell types. Furthermore, ITSCs cultivated as described here could be easily infected with lentiviruses directly in substrate for potential tracing or gene therapeutic approaches. Taken together, the use of human blood plasma as an additive for a completely defined medium points towards a personalisable and autologous cultivation of human neural crest-derived stem cells under clinical grade conditions.
Collapse
Affiliation(s)
- J F W Greiner
- Molecular Neurobiology, University of Bielefeld, Universitaetsstr. 25, D-33501 Bielefeld, Germany
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
30
|
Brunnett R, Deneke C, Beyer A, Schmoecker M, Westenhöfer J, Buchaker S. Gesundheit und Gesundheitsverhalten älterer Männer und Frauen mit türkischem Migrationshintergrund – Ergebnisse einer empirischen Befragung. Gesundheitswesen 2011. [DOI: 10.1055/s-0031-1283417] [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: 10/17/2022]
|
31
|
Gorniak T, Heine R, Mancuso AP, Staier F, Christophis C, Pettitt ME, Sakdinawat A, Treusch R, Guerassimova N, Feldhaus J, Gutt C, Grübel G, Eisebitt S, Beyer A, Gölzhäuser A, Weckert E, Grunze M, Vartanyants IA, Rosenhahn A. X-ray holographic microscopy with zone plates applied to biological samples in the water window using 3rd harmonic radiation from the free-electron laser FLASH. Opt Express 2011; 19:11059-11070. [PMID: 21716334 DOI: 10.1364/oe.19.011059] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
The imaging of hydrated biological samples - especially in the energy window of 284-540 eV, where water does not obscure the signal of soft organic matter and biologically relevant elements - is of tremendous interest for life sciences. Free-electron lasers can provide highly intense and coherent pulses, which allow single pulse imaging to overcome resolution limits set by radiation damage. One current challenge is to match both the desired energy and the intensity of the light source. We present the first images of dehydrated biological material acquired with 3rd harmonic radiation from FLASH by digital in-line zone plate holography as one step towards the vision of imaging hydrated biological material with photons in the water window. We also demonstrate the first application of ultrathin molecular sheets as suitable substrates for future free-electron laser experiments with biological samples in the form of a rat fibroblast cell and marine biofouling bacteria Cobetia marina.
Collapse
Affiliation(s)
- T Gorniak
- Applied Physical Chemistry, University of Heidelberg, Heidelberg, Germany.
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
32
|
Huge V, Müller E, Beyer A, Kraft E, Azad SC. [Patients with chronic pain syndromes. Impact of an individual outpatient therapy program on pain and health-related quality of life]. Schmerz 2011; 24:459-67. [PMID: 20821234 DOI: 10.1007/s00482-010-0968-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
BACKGROUND The study was performed to reveal the effect of an individualized personal outpatient therapy program, based on a multidisciplinary assessment, on pain and health-related quality of life in patients with chronic pain. METHODS Fifty patients were prospectively evaluated before and 3 months after establishment of an individualized outpatient therapy program. Health-related quality of life, pain and pain-related disability, depression and motivation to adopt self-management of chronic pain were assessed. Therapy adherence was tested with a structured interview. RESULTS Only marginal improvements were observed in terms of pain and health-related quality of life. Therapy adherence varied between the different therapies. CONCLUSIONS An individualized personal outpatient therapy program has only marginal effects on pain and health-related quality of life in patients with chronic pain.
Collapse
Affiliation(s)
- V Huge
- Klinik für Anaesthesiologie, Ludwig-Maximilians-Universität München, Campus Grosshadern, Marchioninistr. 15, 81377 München.
| | | | | | | | | |
Collapse
|
33
|
van Dorp WF, Lazić I, Beyer A, Gölzhäuser A, Wagner JB, Hansen TW, Hagen CW. Ultrahigh resolution focused electron beam induced processing: the effect of substrate thickness. Nanotechnology 2011; 22:115303. [PMID: 21301081 DOI: 10.1088/0957-4484/22/11/115303] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/19/2023]
Abstract
It is often suggested that the growth in focused electron beam induced processing (FEBIP) is caused not only by primary electrons, but also (and even predominantly) by secondary electrons (SEs). If that is true, the growth rate for FEBIP can be changed by modifying the SE yield. Results from our Monte Carlo simulations show that the SE yield changes strongly with substrate thickness for thicknesses below the SE escape depth. However, our experimental results show that the growth rate is independent of the substrate thickness. Deposits with an average size of about 3 nm were written on 1 and 9 nm thick carbon substrates. The apparent contradiction between simulation and experiment is explained by simulating the SE emission from a carbon substrate with platinum deposits on the surface. It appears that the SE emission is dominated by the deposits rather than the carbon substrate, even for deposits as small as 0.32 nm(3).
Collapse
Affiliation(s)
- W F van Dorp
- Faculty of Applied Sciences, Delft University of Technology, Delft, The Netherlands.
| | | | | | | | | | | | | |
Collapse
|
34
|
Brusco L, Barone I, Gu G, Beyer A, Fuqua SAW. Abstract P5-06-02: Loss of Rho GDIa Function and Tamoxifen Resistance in ERa-Positive Breast Cancer Cells. Cancer Res 2010. [DOI: 10.1158/0008-5472.sabcs10-p5-06-02] [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: 11/16/2022]
Abstract
Abstract
Background: We have previously shown that increased phosphorylation of the S305 site in ERa via mutation of ERa can lead to tamoxifen (Tam) resistance. We have also discovered that shRNA knockdown of the Rho disassociation inhibitor (Rho GDIa) can render estrogen receptor (ERa)- positive breast cancer cells more aggressive via an increase in their metastatic ability. Rho GDIa is a negative regulator of the Rho family of proteins, which play an important role in the regulation of the actin cytoskeleton. While the Rho pathway is known to influence metastasis in breast and other types of cancers, it is unclear how this pathway impacts on Tam sensitivity. Since loss of Rho GDIa causes an increase in the activity of the downstream Rho proteins (Rho, Rac, and Cdc42), it is possible that increased activity of downstream Rho effectors may lead to Tam resistance through crosstalk with the ERa signaling pathway. Materials and Methods: Rho GDIa was stably silenced in MCF-7 cells using shRNA and its levels validated using Western blot analysis. Kinase assays were perfomed using GST-tagged ERa fragments to assess the effect of various kinases on ERa. ERE-luciferase reporter assays were used to look at ERa transactivation with estrogen and Tam treatment. In vitro-derived Tam-resistant cells were generated by culturing MCF-7 cells in Tam for >6 months.
Results: Knockdown of Rho GDIa in ER-positive breast cancer cells resulted in Tam-resistant growth in vivo. Tam stimulated primary tumor growth in athymic nude mice. Mice injected with Rho GDIa knockdown cells exhibited metastatic lesions to the lung when treated with either estrogen or Tam. No lung tumors were detected in vector control transfected MCF-7 cells. Rhotekin pulldown assays revealed that Rho (A, B, and C), Rac1, and Cdc42 had higher activity in the Rho GDIa knockdown cells as compared to vector control cells. Immunecomplex kinase assays revealed that PAK1, a known downstream effector of the Rho pathway, exhibited increased activation in the Rho GDIa knockdown cells, and that this increased activity led to increased phosphorylation of ERa on the S305 residue. As expected, the acetylation of ERa was decreased when S305 was phosphorylated and this decrease in acetylation was dependent on phosphorylation of S305 since transfection of a plasmid containing a S305A mutation did not display decreased acetylation. ERE-luciferase assays showed that Rho GDIa knockdown cells had higher levels of estrogen and tamoxifen-induced activity in Rho GDIa knockdown cells as compared to vector control cells. Further possible effectors of Rho GDIa are being investigated as possible candidates playing roles in the crosstalk between these two pathways. Interestingly, cells which became Tam-resistant due to long term culture in the presence of Tam, also exhibited a decrease in endogenous Rho GDIa levels.
Discussion: Loss of Rho GDIa in ERa-positive breast cancer cells conferred a Tam-resistant and metastatic phenotype. Cells with decreased Rho GDIa levels displayed increased phosphorylation of ERa, suggesting that there is a level of crosstalk between the Rho family of signaling entwork and the ERa signaling pathway. We hypothesize that disruption of this crosstalk may be an approach to prevent or reverse Tam resistance in patients.
Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P5-06-02.
Collapse
Affiliation(s)
- L Brusco
- Baylor College of Medicine, Houston, TX; University of Calabria, Arcavacata di Rende, Cosenza, Italy
| | - I Barone
- Baylor College of Medicine, Houston, TX; University of Calabria, Arcavacata di Rende, Cosenza, Italy
| | - G Gu
- Baylor College of Medicine, Houston, TX; University of Calabria, Arcavacata di Rende, Cosenza, Italy
| | - A Beyer
- Baylor College of Medicine, Houston, TX; University of Calabria, Arcavacata di Rende, Cosenza, Italy
| | - SAW. Fuqua
- Baylor College of Medicine, Houston, TX; University of Calabria, Arcavacata di Rende, Cosenza, Italy
| |
Collapse
|
35
|
Vyhnalek B, Heilmeier B, Beyer A, Lorenzl S, Schlemmer M, Borasio GD. Spezialisierte Ambulante Palliativversorgung im städtischen Ballungsraum – Erfahrungen der ersten 6 Monate. Palliativmedizin 2010. [DOI: 10.1055/s-0030-1265443] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
|
36
|
Beyer A, Ulbricht S, Bandelin E, Bruß K, Fehlhaber C, Goeze C, Kastirke N, Klinger D, Meyer C, Sannemann J, Hannöver W, John U. Akzeptanz eines gesundheitsfördernden Angebots bei jungen Familien – eine Analyse nach sozialen Merkmalen von Stadtgebieten. Gesundheitswesen 2010. [DOI: 10.1055/s-0030-1266554] [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]
|
37
|
Kastirke N, Ulbricht S, Bandelin E, Beyer A, Bruß K, Fehlhaber C, Goeze C, Klinger D, Sannemann J, John U. Ein proaktives Kurzinterventionsangebot zu gesundheitsriskantem Verhalten: Erreichbarkeit junger Familien im häuslichen Umfeld. Gesundheitswesen 2010. [DOI: 10.1055/s-0030-1266718] [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]
|
38
|
Beyer A, Biziuk M. Comparison of efficiency of different sorbents used during clean-up of extracts for determination of polychlorinated biphenyls and pesticide residues in low-fat food. Food Res Int 2010. [DOI: 10.1016/j.foodres.2009.11.018] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
|
39
|
Bätzing-Feigenbaum J, Pruckner U, Beyer A, Sinn G, Dinter A, Mankertz A, Siedler A, Schubert A, Suckau M. Spotlight on measles 2010: preliminary report of an ongoing measles outbreak in a subpopulation with low vaccination coverage in Berlin, Germany, January-March 2010. Euro Surveill 2010; 15:19527. [PMID: 20394713] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/29/2023] Open
Abstract
Since early January 2010, Berlin has been experiencing a measles outbreak with 62 cases as of 31 March. The index case acquired the infection in India. In recent years, measles incidence in Berlin has been lower than the German average and vaccination coverage in school children has increased since 2001. However, this outbreak involves schools and kindergartens with low vaccination coverage and parents with critical attitudes towards vaccination, which makes the implementation of public health interventions challenging.
Collapse
Affiliation(s)
- J Bätzing-Feigenbaum
- Infectious Disease Protection and Epidemiology Unit, State Office for Health and Social Affairs (LAGeSo), Federal State of Berlin, Berlin, Germany.
| | | | | | | | | | | | | | | | | |
Collapse
|
40
|
Bätzing-Feigenbaum J, Pruckner U, Beyer A, Sinn G, Dinter A, Mankertz A, Siedler A, Schubert A, Suckau M. Spotlight on measles 2010: Preliminary report of an ongoing measles outbreak in a subpopulation with low vaccination coverage in Berlin, Germany, January-March 2010. Euro Surveill 2010. [DOI: 10.2807/ese.15.13.19527-en] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Since early January 2010, Berlin has been experiencing a measles outbreak with 62 cases as of 31 March. The index case acquired the infection in India. In recent years, measles incidence in Berlin has been lower than the German average and vaccination coverage in school children has increased since 2001. However, this outbreak involves schools and kindergartens with low vaccination coverage and parents with critical attitudes towards vaccination, which makes the implementation of public health interventions challenging.
Collapse
Affiliation(s)
- J Bätzing-Feigenbaum
- Infectious Disease Protection and Epidemiology Unit, State Office for Health and Social Affairs (LAGeSo), Federal State of Berlin, Berlin, Germany
| | - U Pruckner
- District Health Office Steglitz-Zehlendorf of Berlin, Berlin, Germany
| | - A Beyer
- District Health Office Steglitz-Zehlendorf of Berlin, Berlin, Germany
| | - G Sinn
- District Health Office Charlottenburg-Wilmersdorf of Berlin, Berlin, Germany
| | - A Dinter
- District Health Office Tempelhof-Schöneberg of Berlin, Berlin, Germany
| | - A Mankertz
- National Reference Centre for Measles, Mumps and Rubella at the Robert Koch-Institute (RKI), Berlin, Germany
| | - A Siedler
- Vaccination Unit, Robert Koch-Institute (RKI), Berlin, Germany
| | - A Schubert
- Infectious Disease Protection and Epidemiology Unit, State Office for Health and Social Affairs (LAGeSo), Federal State of Berlin, Berlin, Germany
| | - M Suckau
- Department for Health, Environment and Consumers Protection (SenGUV), Federal State of Berlin, Berlin, Germany
| |
Collapse
|
41
|
Finsterer U, Betz J, Braun S, Beyer A, Jensen U, Kellermann W. Metabolism of phosphate and calcium after severe accidental trauma. Scandinavian Journal of Clinical and Laboratory Investigation 2010. [DOI: 10.1080/00365518309169096] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
|
42
|
Barone I, Beyer A, Covington K, Tsimelzon A, Ando' S, Fuqua S. Phosphorylation of the Mutant K303R Estrogen Receptor α at Serine 305 Impacts Aromatase Inhibitor Sensitivity. Cancer Res 2009. [DOI: 10.1158/0008-5472.sabcs-09-5053] [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: 11/16/2022]
Abstract
Abstract
Aromatase inhibitors (AIs) are challenging tamoxifen as the treatment of choice for both early and advanced breast cancer in postmenopausal women with estrogen receptor (ER) α-positive diseases. However, resistance frequently occurs. Previously, we identified a lysine to arginine transition at residue 303 (K303R) in ERα in premalignant breast lesions and invasive breast cancers, which confers estrogen hypersensitivity and resistance to the AI Anastrozole (Ana) when transfected in MCF-7 breast cancer cells. To identify genes whose expression was associated with the development of aromatase inhibitor resistance (AIR), we performed microarray analysis, and found a marked increase in the gene expression of different IGF family members in the mutant cells. Immunoblot analysis also revealed elevated constitutive phosphorylation of the IGF-1R/IRS-1/Akt pathway in K303R-expressing cells. Treatment with IGF-1R and Akt inhibitors drastically inhibited proliferation of the K303R-mutant expressing cells, while wild-type ERα-expressing clones showed little reduction of growth by these inhibitors, confirming the increased IGF signaling activation in the mutant cells.Post-translational modifications of ERα, such as phosphorylation, tightly regulate its function, and the K303R mutation resides at a major post-translational modification site, serine (S) residue 305. We found that the mutant was more efficiently phosphorylated than the WT receptor by Akt in vitro, and that the mutant cells exhibited enhanced S305 phosphorylation in vivo. Mutation of S305 to alanine (A) to destroy this phosphorylation site prevented in vitro and in vivo Akt-mediated phosphorylation.The ERα S305 residue is an important site that modifies response to tamoxifen; thus, we questioned whether the S305 site could also influence AI response. To address the role of S305 phosphorylation on AIR, we generated pools of stable transfectants expressing exogenous WT, K303R, or K303R/S305A mutant receptors, and then evaluated for the effects of Ana in soft agar assays. Expression of the K303R/S305A mutant resulted in a significant reduction in the basal non-stimulated growth and sensitivity to Ana compared to K303R ERα-expressing pools, thus mimicking the same response profile of wild-type ERα clones. A selective blocking peptide (S305 peptide, residues 298-308) able to antagonize this phosphorylation reversed AIR. Blockade of S305 phosphorylation also resulted in a specific inhibition of IGF-1R/IRS-1/Akt activation, but only in the mutant cells.Our data suggest that the K303/S305 residues of the ERα mutation may be a novel determinant of aromatase inhibitor response in breast cancer, and blockade of S305 ERα phosphorylation represents a new therapeutic strategy to overcome resistance to hormonal therapies in tumors with the ERα mutation.
Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 5053.
Collapse
Affiliation(s)
| | - A. Beyer
- 1Baylor College of Medicine, TX,
| | | | | | - S. Ando'
- 2University of Calabria, Calabria, Italy
| | - S. Fuqua
- 1Baylor College of Medicine, TX,
| |
Collapse
|
43
|
Lettau M, Beyer A, Janssen O. The PCH family member CIP4 is released from T cells upon activation-induced cell death. Cell Commun Signal 2009. [PMCID: PMC4291844 DOI: 10.1186/1478-811x-7-s1-a81] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2022] Open
|
44
|
Ulbricht S, Beyer A, Meyer C, Rumpf H, John U. Gesunde Atemluft zu Hause – ein Projekt zur Reduzierung der Tabakrauchexposition in Haushalten mit Kleinkindern. Gesundheitswesen 2009. [DOI: 10.1055/s-0029-1239072] [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]
|
45
|
Beyer A, Richter K, Eribo O. Zwei Verlaufsbeobachtungen eines Hamman-Rich-Syndromes mit rezidivierendem Spontanpneumothorax. ROFO-FORTSCHR RONTG 2009. [DOI: 10.1055/s-0029-1226770] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
|
46
|
Beyer A. Die Bewegungsunschärfe intrakardialer Verkalkungen im Schichtbild als diagnostisches Hilfsmittel. ROFO-FORTSCHR RONTG 2009. [DOI: 10.1055/s-0029-1227565] [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]
|
47
|
|
48
|
Händel A, Jünemann AGM, Prokosch HU, Beyer A, Ganslandt T, Grolik R, Klein A, Mrosek A, Michelson G, Kruse FE. [Web-based electronic patient record as an instrument for quality assurance within an integrated care concept]. Klin Monbl Augenheilkd 2009; 226:161-7. [PMID: 19294586 DOI: 10.1055/s-0028-1109193] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
OBJECTIVE A prerequisite for integrated care programmes is the implementation of a communication network meeting quality assurance standards. Against this background the main objective of the integrated care project between the University Eye Hospital Erlangen and the health insurance company AOK Bayern was to evaluate the potential and the acceptance of a web-based electronic patient record in the context of cataract and retinal surgery. METHODS Standardised modules for capturing pre-, intra- and post-operative data on the basis of clinical pathway guidelines for cataract- and retinal surgery have been developed. There are 6 data sets recorded per patient (1 pre-operative, 1 operative, 4-6 post-operative). For data collection, a web-based communication system (Soarian Integrated Care) has been chosen which meets the high requirements in data security, as well as being easy to handle. This teleconsultation system and the embedded electronic patient record are independent of the software used by respective offices and hospitals. Data transmission and storage were carried out in real-time. RESULTS At present, 101 private ophthalmologists are taking part in the IGV contract with the University Eye Hospital Erlangen. This corresponds to 52% of all private ophthalmologists in the region. During the period from January 1st 2006 to December 31st 2006, 1844 patients were entered. Complete documentation was achieved in 1390 (75%) of all surgical procedures. For evaluation of this data, a multidimensional report and analysis tool (Cognos) was used. The deviation from target refraction as one quality indicator was in the mean 0.09 diopter. CONCLUSIONS The web-based patient record used in this project was highly accepted by the private ophthalmologists. However there are still general concerns against the exchange of medical data via the internet. Nevertheless, the web-based patient record is an essential tool for a functional integration between the ambulatory and stationary health-care units. In addition to the telemedicine functions of the system, we achieved the export of the data to a data warehouse system in order to provide a flexible and powerful tool for quality assurance analysis and reporting.
Collapse
Affiliation(s)
- A Händel
- Augenklinik, Universitätsklinikum Erlangen, Erlangen.
| | | | | | | | | | | | | | | | | | | |
Collapse
|
49
|
|
50
|
|