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Yagdiran A, Otto-Lambertz C, Sondermann B, Ernst A, Jochimsen D, Sobottke R, Siewe J, Eysel P, Jung N. Can we predict favourable quality of life after surgically treated vertebral osteomyelitis? Analysis of a prospective study. Arch Orthop Trauma Surg 2022; 143:2317-2324. [PMID: 35359162 PMCID: PMC10110645 DOI: 10.1007/s00402-022-04431-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/14/2021] [Accepted: 03/12/2022] [Indexed: 11/02/2022]
Abstract
PURPOSE Vertebral osteomyelitis (VO) is a severe clinical entity associated with significant morbidity and mortality. Several studies have showed that successful treatment of VO patients leads to significantly improved quality of life (QoL). Nevertheless, QoL levels of these patients remained below those of the general population. There are rarely studies focusing on predicting factors for favourable QoL after surgically treated VO. The aim of this study was to identify factors influencing positively the QoL of patients undergoing surgery for VO. METHODS We conducted a prospective monocentric study including surgically treated VO patients from 2008 to 2016. Data were collected before (T0) and 1 year (T1) after surgery. Primary outcome was favourable QoL defined as back pain with disability restricting normal life activity with a cutoff value ≥ 12 on Oswestry Disability Index (ODI). ETHICS Ethical approval was given by the Faculty of Medicine at the University of Cologne (09-182). RESULTS A total of 119 patients surviving 1 year after surgically treated VO were analysed. Favourable QoL was achieved in 35/119 patients. On multivariate analysis, younger age (hazard ratio = HR: 0.95; 95% CI 0.91-0.99; p = 0.022), lower albumin (HR: 0.9; 0.83-0.98; p = 0.019) an ASA score ≤ 2 (HR:4.24; 95%CI 1.42-12.68; p = 0.010), and a lower preoperative leg pain on the VAS (HR: 0.86; 95% CI 0.76-0.97; p = 0.018) were identified as independent risk factors for favourable QoL. Interestingly, the absence of neurological deficits was not predictive for a favourable outcome by means of QoL. CONCLUSION One-third of surgically treated VO patients (29%) in our cohort achieved favourable QoL by means of ODI. Our findings can facilitate an estimation of the prognosis when informing the patient before surgery, and underscore that spine disability questionnaires, such as ODI, measuring QoL, are mandatory to evaluate comprehensively the outcome of this entity.
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Altay L, Liakopoulos S, Berghold A, Rosenberger KD, Ernst A, de Breuk A, den Hollander AI, Fauser S, Schick T. Genetic and environmental risk factors for reticular pseudodrusen in the EUGENDA study. Mol Vis 2021; 27:757-767. [PMID: 35136347 PMCID: PMC8763662] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2020] [Accepted: 12/30/2021] [Indexed: 12/03/2022] Open
Abstract
PURPOSE The purpose of this study was to analyze genetic and nongenetic associations with reticular pseudodrusen (RPD) in patients with and without age-related macular degeneration (AMD). METHODS This case-control study included 2,719 consecutive subjects from the prospective multicenter European Genetic Database (EUGENDA). Color fundus photographs and optical coherence tomography (OCT) scans were evaluated for the presence of AMD and RPD. Association of RPD with 39 known AMD polymorphisms and various nongenetic risk factors was evaluated. Stepwise backward variable selection via generalized linear models (GLMs) was performed based on models including the following: a) age, sex, and genetic factors and b) all predictors. Receiver operating characteristic (ROC) curves and the areas under the curve (AUCs) were determined. RESULTS RPD were present in 262 cases (no AMD, n = 9 [0.7%; early/intermediate AMD, n = 75 [12.4%]; late AMD, n = 178 [23.8%]). ROC analysis of the genetic model including age, APOE rs2075650, ARMS2 rs10490924, CFH rs800292, CFH rs12144939, CFI rs10033900, COL8A1 rs13081855, COL10A1 rs3812111, GLI3 rs2049622, and SKIV2L rs4296082 revealed an AUC of 0.871. Considering all possible predictors, backward selection revealed a slightly different set of genetic factors, as well as the following nongenetic risk factors: smoking, rheumatoid arthritis, steroids, antiglaucomatous drugs, and past sunlight exposure; the results showed an AUC of 0.886. CONCLUSIONS RPD share a variety of genetic and nongenetic risk factors with AMD. Future AMD grading systems should integrate RPD as an important risk phenotype.
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Petrov EK, Ernst A, Menshchikova TV, Chulkov EV. Intrinsic Magnetic Topological Insulator State Induced by the Jahn-Teller Effect. J Phys Chem Lett 2021; 12:9076-9085. [PMID: 34516740 DOI: 10.1021/acs.jpclett.1c02396] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
The Jahn-Teller effect is a geometrical distortion which lowers the system symmetry and lifts orbital degeneracy in molecules and solids. It affects a wide range of properties, including magnetic and band structures. In this work we propose a family of Cr-containing intrinsic magnetic topological insulator materials which are subjected to a pseudo-Jahn-Teller effect-CrBi2Se4, CrBi2Te2Se2, and CrBi2Te4. Using first-principles calculations we study their properties and investigate the impact of Jahn-Teller distortions on the electronic and magnetic properties. We show that these distortions can significantly affect magnetic anisotropy energy and band structure. Without the distortions accounted for, all three of the compounds exhibit a semimetallic band structure. The distortions open a band gap, which in the cases of CrBi2Te2Se2 and CrBi2Te4 is inverted. We also investigate the CrBi2Te2Se2 and CrBi2Te4 surface band structure and demonstrate that the surface states have a topological origin.
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Steinmetz T, Ernst A, Hellmich M, Heinz M, Totzke U. Effectiveness of Long-Term Treatment of Multiple Myeloma in Regular Care: Comparison of a Longitudinal and a Cross-Sectional Analysis Approach. Oncol Res Treat 2021; 44:662-671. [PMID: 34530428 DOI: 10.1159/000519419] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2021] [Accepted: 09/01/2021] [Indexed: 11/19/2022]
Abstract
INTRODUCTION New drugs for multiple myeloma have considerably increased the options for consecutive treatment lines in regular care. Official treatment guidelines still discuss several regimens per line, and therefore, current practice is of topical interest. Large cross-sectional studies revealed a greater than linear loss of patients reaching consecutive treatment lines of ever decreasing effectiveness. METHODS In a longitudinal approach, we analyzed data of all 145 multiple myeloma patients treated in our outpatient clinic in Germany between January 1, 2012, and December 31, 2019, using a time-to-event analysis with death as competitive risk. RESULTS The estimated incidences of reaching the 2nd, 3rd, 4th, and 5th lines of therapy were 88, 66, 44, and 30%, respectively. Median times to subsequent treatment lines were 34, 18, 14, 13, and 15 months, respectively. DISCUSSION Percentages of patients reaching later therapy lines were considerably greater than predicted by cross-sectional studies and median times after the 1st line did not suggest a further decrease in effectiveness, while use of new drug regimens was similar to that reported in cross-sectional studies. CONCLUSION Effectiveness of later therapy lines appears to be underestimated by cross-sectional analyses, and the conveyed focus on 1st-line treatment for multiple myeloma needs to be scrutinized.
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Fedorov AV, Poelchen G, Eremeev SV, Schulz S, Generalov A, Polley C, Laubschat C, Kliemt K, Kaya N, Krellner C, Chulkov EV, Kummer K, Usachov DY, Ernst A, Vyalikh DV. Insight into the Temperature Evolution of Electronic Structure and Mechanism of Exchange Interaction in EuS. J Phys Chem Lett 2021; 12:8328-8334. [PMID: 34428055 DOI: 10.1021/acs.jpclett.1c02274] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Discovered in 1962, the divalent ferromagnetic semiconductor EuS (TC = 16.5 K, Eg = 1.65 eV) has remained constantly relevant to the engineering of novel magnetically active interfaces, heterostructures, and multilayer sequences and to combination with topological materials. Because detailed information on the electronic structure of EuS and, in particular, its evolution across TC is not well-represented in the literature but is essential for the development of new functional systems, the present work aims at filling this gap. Our angle-resolved photoemission measurements complemented with first-principles calculations demonstrate how the electronic structure of EuS evolves across a paramagnetic-ferromagnetic transition. Our results emphasize the importance of the strong Eu 4f-S 3p mixing for exchange-magnetic splittings of the sulfur-derived bands as well as coupling between f and d orbitals of neighboring Eu atoms to derive the value of TC accurately. The 4f-3p mixing facilitates the coupling between 4f and 5d orbitals of neighboring Eu atoms, which mainly governs the exchange interaction in EuS.
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Berthold F, Rosswog C, Christiansen H, Frühwald M, Hemstedt N, Klingebiel T, Fröhlich B, Schilling FH, Schmid I, Simon T, Hero B, Fischer M, Ernst A. Clinical and molecular characterization of patients with stage 4(M) neuroblastoma aged less than 18 months without MYCN amplification. Pediatr Blood Cancer 2021; 68:e29038. [PMID: 33826231 DOI: 10.1002/pbc.29038] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/25/2021] [Revised: 02/23/2021] [Accepted: 03/13/2021] [Indexed: 11/06/2022]
Abstract
INTRODUCTION The survival of children with stage 4(M) neuroblastoma without MYCN amplification and below the age of 18 months is considered better than the still dismal outcome of older high-risk neuroblastoma patients. This study analyzes the impact of clinical and molecular characteristics on the long-term outcome. PATIENTS AND METHODS Clinical presentation, survival, and recurrence patterns of patients enrolled onto trials NB90, NB97, and NB2004 were retrospectively analyzed. Gene expression signatures based on RNA microarrays (TH10) were investigated if tumor material was available. RESULTS Between 1990 and 2015, 177 patients with stage 4(M) MYCN nonamplified neuroblastoma aged less than 18 months at diagnosis were eligible. After a median follow-up of 9.7 years (IQR 5.0, 13.4), the proportions of 10-year event-free survival (EFS) and overall survival (OS) were 73% (95% confidence interval [CI] 67-79%) and 86% (95% CI 80-92%), respectively. Of the 27 neuroblastoma recurrences, 44% occurred in more than one site. Four additional patients presented histologically mature ganglioneuroma at recurrence. Six patients developed a secondary malignancy. The secondary 5-year EFS and OS of the 27 patients with neuroblastoma recurrence were 44% and 59%, respectively. TH10 gene expression signature was not prognostically predictive in the investigated subcohort. CONCLUSION The outcome of patients with stage 4(M) neuroblastoma aged less than 18 months is favorable when treated with high-risk or otherwise intensive therapy. The development of secondary malignancies and the potential of maturation to ganglioneuroma call for a controlled stepwise reduction of treatment intensity.
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Paischer S, Buczek PA, Buczek N, Eilmsteiner D, Ernst A. Eigenmodes of a disordered FeCo magnonic crystal at finite temperatures. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2021; 33:335804. [PMID: 34102617 DOI: 10.1088/1361-648x/ac0939] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/12/2021] [Accepted: 06/08/2021] [Indexed: 06/12/2023]
Abstract
In this report we present a systematic study of the magnonic modes in the disordered Fe0.5Co0.5alloy based on the Heisenberg Hamiltonian using two complementary approaches. In order to account for substitutional disorder, on the one hand we directly average the transverse magnetic susceptibility in real space over different disorder configurations and on the other hand we use the coherent potential approximation (CPA). While the method of direct averaging is numerically exact, it is computationally expensive and limited by the maximal size of the supercell which can be simulated on a computer. On the contrary the CPA does not suffer from this drawback and yields a cheap numerical scheme. Therefore, we additionally compare the results of these two approaches and show that the CPA gives very good results for most of the magnetic properties considered in this report, including the magnon energies and the spatial shape of the eigenmodes. However, it turns out that while reproducing the general trend, the CPA systematically underestimates the disorder induced damping of the magnons. This provides evidence that the physics of impurity scattering in this system is governed by non-local effects missing in the CPA. Finally, we study the real space eigenmodes of the system, including their spatial shapes, and analyze their temperature dependence within the random phase approximation.
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Rieg S, Ernst A, Peyerl-Hoffmann G, Joost I, Camp J, Hellmich M, Kern WV, Kaasch AJ, Seifert H. Combination therapy with rifampicin or fosfomycin in patients with Staphylococcus aureus bloodstream infection at high risk for complications or relapse: results of a large prospective observational cohort. J Antimicrob Chemother 2021; 75:2282-2290. [PMID: 32355950 DOI: 10.1093/jac/dkaa144] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2019] [Revised: 03/17/2020] [Accepted: 03/23/2020] [Indexed: 01/27/2023] Open
Abstract
OBJECTIVES To investigate whether Staphylococcus aureus bloodstream infection (SAB) patients at high risk for complications or relapse benefit from combination therapy with adjunctive rifampicin or fosfomycin. METHODS In this post hoc analysis, SAB patients with native valve infective endocarditis, osteoarticular infections or implanted foreign devices were included. The co-primary endpoints were all-cause 90 day mortality and death or SAB-related late complications within 180 days. To overcome treatment selection bias and account for its time dependence, inverse probability of treatment weights were calculated and included in marginal structural Cox proportional hazard models (MSCMs). RESULTS A total of 578 patients were included in the analysis, of which 313 (54%) received combination therapy with either rifampicin (n = 242) or fosfomycin (n = 58). In the multivariable MSCM, combination therapy was associated with a better outcome, that is, a lower rate of death or SAB-related late complications within 180 days (HR 0.65, 95% CI 0.46-0.92). This beneficial effect was primarily seen in patients with implanted foreign devices, in which combination therapy was associated with a lower rate of death or SAB-related late complications within 180 days (HR 0.53, 95% CI 0.35-0.79) and a lower 90 day mortality (HR 0.57, 95% CI 0.36-0.91). Upon agent-specific stratification, we found no significant differences in outcomes between combination therapy containing rifampicin and fosfomycin; however, the number of patients in most subgroups was not large enough to draw firm conclusions. CONCLUSIONS In patients with implanted foreign devices, combination therapy was associated with a better long-term outcome. Larger prospective studies are needed to validate these findings.
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Cicalese PA, Rizvi SA, Roufosse C, Batal I, Hellmich M, Ernst A, Moos K, Clahsen-van Groningen M, Weidemann A, Mohan C, Nguyen HV, Becker JU. MO078DEEP LEARNING DIAGNOSIS OF ANTIBODY-MEDIATED REJECTION (AMR) ON GLOMERULAR TRANSECTIONS. Nephrol Dial Transplant 2021. [DOI: 10.1093/ndt/gfab078.0014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Abstract
Background and Aims
Antibody-mediated rejection (AMR) is among the most common causes for kidney transplant loss. The histological diagnosis is hampered by significant intra- and interobserver variability. Training a deep learning classifier for the recognition of AMR on glomerular transections as the most decisive compartment could establish a reliable and perfectly reproducible diagnostic method.
Method
We identified 48 biopsies with AMR (all positive for donor-specific antibody) and 38 biopsies without AMR according to Banff 2017 from our archive. Photographs were taken from all non-globally sclerosed glomeruli on two PAS-stained level sections, yielding a total of 1,655 images as a training set. 1,503 images could be labeled by three experienced nephropathologists conclusively as AMR or non-AMR in a blinded fashion. We trained a DenseNet-121 classifier (pre-trained on ImageNet) with basic online augmentation. In addition, we implemented StyPath++, a data augmentation algorithm that leverages a style transfer mechanism, addressing significant domain shifts in histopathology. Each sample was assigned a consensus label generated by the pathologists.
Results
Five-fold cross validation schemes produced a weighted glomerular level performance of 88.1%, exceeding the baseline performance by 5%. The improved generalization ability of the StyPath++ augmented model shows that it is possible to construct reliable glomerular classification algorithms with scarce datasets.
Conclusion
We created a deep learning classifier with excellent performance and reproducibility for the diagnosis of AMR on glomerular transections. We plan to expand the training set, including challenging cases of differential diagnoses like glomerulonephritis or other glomerulopathies. We are also interested in external clinicopathological datasets to further validate our results.
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Maryenko D, Kawamura M, Ernst A, Dugaev VK, Sherman EY, Kriener M, Bahramy MS, Kozuka Y, Kawasaki M. Interplay of spin-orbit coupling and Coulomb interaction in ZnO-based electron system. Nat Commun 2021; 12:3180. [PMID: 34039969 PMCID: PMC8155003 DOI: 10.1038/s41467-021-23483-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/11/2020] [Accepted: 04/30/2021] [Indexed: 11/09/2022] Open
Abstract
Spin-orbit coupling (SOC) is pivotal for various fundamental spin-dependent phenomena in solids and their technological applications. In semiconductors, these phenomena have been so far studied in relatively weak electron-electron interaction regimes, where the single electron picture holds. However, SOC can profoundly compete against Coulomb interaction, which could lead to the emergence of unconventional electronic phases. Since SOC depends on the electric field in the crystal including contributions of itinerant electrons, electron-electron interactions can modify this coupling. Here we demonstrate the emergence of the SOC effect in a high-mobility two-dimensional electron system in a simple band structure MgZnO/ZnO semiconductor. This electron system also features strong electron-electron interaction effects. By changing the carrier density with Mg-content, we tune the SOC strength and achieve its interplay with electron-electron interaction. These systems pave a way to emergent spintronic phenomena in strong electron correlation regimes and to the formation of quasiparticles with the electron spin strongly coupled to the density.
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Eremeev SV, Rusinov IP, Koroteev YM, Vyazovskaya AY, Hoffmann M, Echenique PM, Ernst A, Otrokov MM, Chulkov EV. Topological Magnetic Materials of the (MnSb 2Te 4)·(Sb 2Te 3) n van der Waals Compounds Family. J Phys Chem Lett 2021; 12:4268-4277. [PMID: 33908787 DOI: 10.1021/acs.jpclett.1c00875] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Using density functional theory, we propose the (MnSb2Te4)·(Sb2Te3)n family of stoichiometric van der Waals compounds that harbor multiple topologically nontrivial magnetic phases. In the ground state, the first three members of the family (n = 0, 1, 2) are 3D antiferromagnetic topological insulators, while for n ≥ 3 a special phase is formed, in which a nontrivial topological order coexists with a partial magnetic disorder in the system of the decoupled 2D ferromagnets, whose magnetizations point randomly along the third direction. Furthermore, due to a weak interlayer exchange coupling, these materials can be field-driven into the FM Weyl semimetal (n = 0) or FM axion insulator states (n ≥ 1). Finally, in two dimensions, we reveal these systems to show intrinsic quantum anomalous Hall and AFM axion insulator states, as well as quantum Hall state, achieved under external magnetic field. Our results demonstrate that MnSb2Te4 is not topologically trivial as was previously believed that opens possibilities of realization of a wealth of topologically nontrivial states in the (MnSb2Te4)·(Sb2Te3)n family.
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Berthold F, Spix C, Erttmann R, Hero B, Michaelis J, Treuner J, Ernst A, Schilling FH. Neuroblastoma Screening at 1 Year of Age: The Final Results of a Controlled Trial. JNCI Cancer Spectr 2021; 5:pkab041. [PMID: 34240006 PMCID: PMC8259619 DOI: 10.1093/jncics/pkab041] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2020] [Revised: 02/06/2021] [Accepted: 04/28/2021] [Indexed: 12/21/2022] Open
Abstract
Background Neuroblastoma screening aims to reduce neuroblastoma-related mortality. A controlled trial showed no reduction in stage 4 disease incidence and preliminary mortality data. This article presents epidemiologic and clinical data 20 years after cessation of the screening program. Methods The patients with detected disease in the screening area were compared with the clinically diagnosed patients in the control area and in the prestudy and poststudy cohorts. All statistical tests were 2-sided. Results The cumulative incidence for children aged 1 to 6 years in the birth study cohorts (1994-1999) in the screening arm was 13.4 cases per 100 000 births (95% confidence interval [CI] = 12.2 to 14.6) based on 61.2% of screening participants and 38.8% of nonparticipants. Screening participants had a cumulative incidence of 15.7 (95% CI = 14.0 to 17.4) per 100 000 births. The cumulative incidence in the contemporary control cohort was 9.3 (95% CI = 8.2 to 10.3) per 100 000 births, 7.6 (95% CI = 6.8 to 8.4) in the prestudy cohort, and 8.1 (95% CI = 7.4 to 8.9) in the poststudy cohort from 2000 to 2004 (P < .001 each). The increased incidence in the screening cohort was restricted to stages 1 through 3, while stage 4 incidence was not reduced. The cumulative mortality for deaths within 10 years from diagnosis and per 100 000 births remained unchanged. Patients with stage 4 disease detected by screening had better biological characteristics and an improved outcome compared with those stage 4 cases not detected by screening. Conclusions Neuroblastoma screening at 1 year of age reduced neither stage 4 incidence nor neuroblastoma mortality and was affected by overdiagnosis, leading to unnecessary treatment. A few screening-detected stage 4 cases represent a biologically interesting subgroup but do not change the recommendation to close the “catecholamine-based neuroblastoma screening book.”
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Zakeri K, Hjelt A, Maznichenko IV, Buczek P, Ernst A. Nonlinear Decay of Quantum Confined Magnons in Itinerant Ferromagnets. PHYSICAL REVIEW LETTERS 2021; 126:177203. [PMID: 33988456 DOI: 10.1103/physrevlett.126.177203] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/29/2021] [Accepted: 04/06/2021] [Indexed: 06/12/2023]
Abstract
Quantum confinement leads to the emergence of several magnon modes in ultrathin layered magnetic structures. We probe the lifetime of these quantum confined modes in a model system composed of three atomic layers of Co grown on different surfaces. We demonstrate that the quantum confined magnons exhibit nonlinear decay rates, which strongly depend on the mode number, in sharp contrast to what is assumed in the classical dynamics. Combining the experimental results with those of linear-response density-functional calculations we provide a quantitative explanation for this nonlinear damping effect. The results provide new insights into the decay mechanism of spin excitations in ultrathin films and multilayers and pave the way for tuning the dynamical properties of such structures.
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Eilmsteiner D, Wang XG, Chotorlishvili L, Paischer S, Hoffmann M, Buczek P, Ernst A. Asymmetry in the propagation of vortex domain wall artificial skyrmion composite system. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2021; 33:185803. [PMID: 33711837 DOI: 10.1088/1361-648x/abee39] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/21/2020] [Accepted: 03/12/2021] [Indexed: 06/12/2023]
Abstract
We studied the propagation of an artificial skyrmion coupled to the vortex domain wall (VDW). We discovered the following effect: depending on the propagation's direction, the dynamics of the coupled skyrmion VDW can be faster than the isolated VDW's velocity. The reason for such behavior is the structural distortion that occurs in the coupled system. We interpret the numerical results in terms of the modified Thiele's equation. In particular, increasing the Thiele's equation counteractive coefficient leads to the perfect fitting with the micromagnetic simulation results.
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Reid MJA, Prado P, Brosnan H, Ernst A, Spindler H, Celentano J, Wall-Shui M, Sachdev D. Assessing Testing Strategies and Duration of Quarantine in Contact Tracing for SARS-CoV-2: A Retrospective Study of San Francisco's COVID-19 Contact Tracing Program, June-August 2020. Open Forum Infect Dis 2021; 8:ofab171. [PMID: 34316499 PMCID: PMC8083597 DOI: 10.1093/ofid/ofab171] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2021] [Accepted: 03/31/2021] [Indexed: 02/01/2023] Open
Abstract
We sought to assess the proportion of elicited close contacts diagnosed with coronavirus disease 2019 at the start of and before exiting quarantine in San Francisco. From June 8 to August 31, 6946 contacts were identified: 3008 (46.3%) were tested, 940 (13.5%) tested positive, and 90% tested positive in the first 9 days of quarantine.
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Schumacher-Kuckelkorn R, Atra A, Belli ML, den Engelsman G, Fréneaux P, Gauthier A, Heijlaerts-Klever A, Scuderi F, Senent Peris L, Tewari S, Zapletal O, Ernst A, Berthold F. The reliability of bone marrow cytology as response criterion in metastatic neuroblastoma. Pediatr Blood Cancer 2021; 68:e28819. [PMID: 33245195 DOI: 10.1002/pbc.28819] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/10/2020] [Revised: 10/20/2020] [Accepted: 11/03/2020] [Indexed: 12/27/2022]
Abstract
BACKGROUND The quantitative assessment of neuroblastoma cell content in bone marrow aspirates for response evaluation has been introduced recently. Data on the concordance of interobserver reports are lacking so far. METHODS Investigators of seven European countries representing national reference or large oncological centers convened in 2016. They agreed to quantitatively assess routine bone marrow smears of the participating institutions and to discuss the discrepant results in joint meetings. RESULTS From 2017 through 2019, three cytology rounds with 24, 28, and 28 bone marrow samples were run evaluating the representativity of the smears (yes/[restricted]/no) and the presence of tumor cells (yes/no and %). The comparison of the reports using κ (Fleiss) and α (Krippendorff) statistics demonstrated no robust reliabilities. The agreement on the representativity was moderate to poor, on the presence of tumor cells moderate to good, and on the percentage of tumor cells slight to moderate. Though the value of cytology is unquestioned to detect even tiny metastatic cells in bone marrow, the investigators unanimously agreed that a reliable quantification of the tumor cell content in bone marrow smears is unrealistic. For the key issue of representativity, a new practical definition was developed. CONCLUSION For any work with bone marrow aspirates, the representativity of the material is of paramount importance. A practical definition is proposed. A reliable quantitative cytological assessment of tumor cell content in bone marrow aspirates is not feasible in metastatic neuroblastoma. Therefore, its use as response criterion should be reconsidered.
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Wang XG, Chotorlishvili L, Arnold N, Dugaev VK, Maznichenko I, Barnaś J, Buczek PA, Parkin SSP, Ernst A. Plasmonic Skyrmion Lattice Based on the Magnetoelectric Effect. PHYSICAL REVIEW LETTERS 2020; 125:227201. [PMID: 33315433 DOI: 10.1103/physrevlett.125.227201] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/29/2020] [Revised: 08/04/2020] [Accepted: 10/01/2020] [Indexed: 06/12/2023]
Abstract
The physical mechanism of the plasmonic skyrmion lattice formation in a magnetic layer deposited on a metallic substrate is studied theoretically. The optical lattice is the essence of the standing interference pattern of the surface plasmon polaritons created through coherent or incoherent laser sources. The nodal points of the interference pattern play the role of lattice sites where skyrmions are confined. The confinement appears as a result of the magnetoelectric effect and the electric field associated with the plasmon waves. The proposed model is applicable to yttrium iron garnet and single-phase multiferroics and combines plasmonics and skyrmionics.
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Renner RA, Groß VJ, Ernst A, Hellmich M, Erren TC. [Epidemiological Studies on the Association between Chronic Exposure to Road Traffic Noise and Blood Pressure: A Systematic Review with Meta-Analyses]. DAS GESUNDHEITSWESEN 2020; 83:384-397. [PMID: 32693422 DOI: 10.1055/a-1165-1797] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
AIM The aim of this study was to review epidemiological studies on the association between chronic exposures to road traffic noise and prevalence of arterial hypertension as well as blood pressure by using meta-analyses. METHODS A systematic literature search in the databases Medline® and Web of science™ as well as the database OpenGrey was conducted to identify suitable studies, namely epidemiological observational studies assessing objective exposures to road traffic noise at the subject's home place with analysis of their potential associations with arterial hypertension or blood pressure. Whenever possible, overall effects for the different relationships were estimated with meta-analyses. For statistical analyses R for windows was used. RESULTS A total of 31 eligible studies were identified. Meta-analyses were conducted for potential association between road traffic noise and prevalence of arterial hypertension in adults and for association with systolic and diastolic blood pressure in adults and children. There was a significant (p<0.01) increase of risk for arterial hypertension in adults when exposed to chronic road traffic noise with an increment of 7% per 5 dB(A). Overall effects for systolic blood pressure were positive but weak for children as well as adults without any statistical significance. For diastolic blood pressure there appeared to be no relationship with chronic exposure to road traffic noise in either of the two groups. CONCLUSION Considering the multiple methodological limitations of studies examined as well as the high level of heterogeneity in all random effects models, the estimated overall effects must be interpreted with caution. To examine potential associations between road traffic noise and arterial hypertension or measured blood pressure appropriately, more prospective cohort studies are necessary with precise assessments of noise exposure as well as clinical endpoints and with adjustments for relevant cofactors.
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Kjersgaard C, Arendt L, Ernst A, Lindhard M, Olsen J, Henriksen T, Strandberg-Larsen K, Ramlau-Hansen C. Maternal lifestyle in pregnancy and hypospadias: A study within two large Danish birth cohorts. EUR UROL SUPPL 2020. [DOI: 10.1016/s2666-1683(20)33230-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022] Open
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Becker JU, Mayerich D, Padmanabhan M, Barratt J, Ernst A, Boor P, Cicalese PA, Mohan C, Nguyen HV, Roysam B. Artificial intelligence and machine learning in nephropathology. Kidney Int 2020; 98:65-75. [PMID: 32475607 PMCID: PMC8906056 DOI: 10.1016/j.kint.2020.02.027] [Citation(s) in RCA: 44] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2019] [Revised: 01/03/2020] [Accepted: 02/12/2020] [Indexed: 12/15/2022]
Abstract
Artificial intelligence (AI) for the purpose of this review is an umbrella term for technologies emulating a nephropathologist's ability to extract information on diagnosis, prognosis, and therapy responsiveness from native or transplant kidney biopsies. Although AI can be used to analyze a wide variety of biopsy-related data, this review focuses on whole slide images traditionally used in nephropathology. AI applications in nephropathology have recently become available through several advancing technologies, including (i) widespread introduction of glass slide scanners, (ii) data servers in pathology departments worldwide, and (iii) through greatly improved computer hardware to enable AI training. In this review, we explain how AI can enhance the reproducibility of nephropathology results for certain parameters in the context of precision medicine using advanced architectures, such as convolutional neural networks, that are currently the state of the art in machine learning software for this task. Because AI applications in nephropathology are still in their infancy, we show the power and potential of AI applications mostly in the example of oncopathology. Moreover, we discuss the technological obstacles as well as the current stakeholder and regulatory concerns about developing AI applications in nephropathology from the perspective of nephropathologists and the wider nephrology community. We expect the gradual introduction of these technologies into routine diagnostics and research for selective tasks, suggesting that this technology will enhance the performance of nephropathologists rather than making them redundant.
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Wang Z, Vergniory MG, Kushwaha S, Hirschberger M, Chulkov EV, Ernst A, Ong NP, Cava RJ, Bernevig BA. Publisher's Note: Time-Reversal-Breaking Weyl Fermions in Magnetic Heusler Alloys [Phys. Rev. Lett. 117, 236401 (2016)]. PHYSICAL REVIEW LETTERS 2020; 124:239901. [PMID: 32603160 DOI: 10.1103/physrevlett.124.239901] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/21/2020] [Indexed: 06/11/2023]
Abstract
This corrects the article DOI: 10.1103/PhysRevLett.117.236401.
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Berthold F, Faldum A, Ernst A, Boos J, Dilloo D, Eggert A, Fischer M, Frühwald M, Henze G, Klingebiel T, Kratz C, Kremens B, Krug B, Leuschner I, Schmidt M, Schmidt R, Schumacher-Kuckelkorn R, von Schweinitz D, Schilling FH, Theissen J, Volland R, Hero B, Simon T. Extended induction chemotherapy does not improve the outcome for high-risk neuroblastoma patients: results of the randomized open-label GPOH trial NB2004-HR. Ann Oncol 2020; 31:422-429. [PMID: 32067684 DOI: 10.1016/j.annonc.2019.11.011] [Citation(s) in RCA: 26] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2019] [Revised: 11/12/2019] [Accepted: 11/13/2019] [Indexed: 01/10/2023] Open
Abstract
BACKGROUND Long-term survival of high-risk neuroblastoma patients is still below 50% despite intensive multimodal treatment. This trial aimed to address whether the addition of two topotecan-containing chemotherapy courses compared to standard induction therapy improves event-free survival (EFS) of these patients. PATIENTS AND METHODS An open-label, multicenter, prospective randomized controlled trial was carried out at 58 hospitals in Germany and Switzerland. Patients aged 1-21 years with stage 4 neuroblastoma and patients aged 6 months to 21 years with MYCN-amplified tumors were eligible. The primary endpoint was EFS. Patients were randomly assigned to standard induction therapy with six chemotherapy courses or to experimental induction chemotherapy starting with two additional courses of topotecan, cyclophosphamide, and etoposide followed by standard induction chemotherapy (eight courses in total). After induction chemotherapy, all patients received high-dose chemotherapy with autologous hematopoietic stem cell rescue and isotretinoin for consolidation. Radiotherapy was applied to patients with active tumors at the end of induction chemotherapy. RESULTS Of 536 patients enrolled in the trial, 422 were randomly assigned to the control arm (n = 211) and the experimental arm (n = 211); the median follow-up time was 3.32 years (interquartile range 1.65-5.92). At data lock, the 3-year EFS of experimental and control patients was 34% and 32% [95% confidence Interval (CI) 28% to 40% and 26% to 38%; P = 0.258], respectively. Similarly, the 3-year overall survival of the patients did not differ [54% and 48% (95% CI 46% to 62% and 40% to 56%), respectively; P = 0.558]. The response to induction chemotherapy was not different between the arms. The median number of non-fatal toxicities per patient was higher in the experimental group while the median number of toxicities per chemotherapy course was not different. CONCLUSION While the burden for the patients was increased by prolonging the induction chemotherapy and the toxicity, the addition of two topotecan-containing chemotherapy courses did not improve the EFS of high-risk neuroblastoma patients and thus cannot be recommended. CLINICAL TRIALS. GOV NUMBER NCT number 03042429.
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Qin HJ, Tsurkan S, Ernst A, Zakeri K. Experimental Realization of Atomic-Scale Magnonic Crystals. PHYSICAL REVIEW LETTERS 2019; 123:257202. [PMID: 31922781 DOI: 10.1103/physrevlett.123.257202] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/05/2019] [Indexed: 06/10/2023]
Abstract
We introduce a new approach of materials design for terahertz magnonics making use of quantum confinement of terahertz magnons in layered ferromagnets. We show that in atomically designed multilayers composed of alternating atomic layers of ferromagnetic metals one can efficiently excite different magnon modes associated with the quantum confinement in the third dimension, i.e., the direction perpendicular to the layers. We demonstrate experimentally that the magnonic band structure of these systems can be tuned by changing the material combination and the number of atomic layers. We realize the idea of opening band gaps, with a size of up to several tens of millielectronvolts, between different terahertz magnon bands and thereby report on the first step toward the realization of atomic-scale magnonic crystals.
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Ernst A. [Pediatric balance disorders]. HNO 2019; 68:359. [PMID: 31659378 DOI: 10.1007/s00106-019-00765-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Kreitz K, Ernst A, Schmidt R, Simon T, Fischer M, Volland R, Hero B, Berthold F. A new risk score for patients after first recurrence of stage 4 neuroblastoma aged ≥18 months at first diagnosis. Cancer Med 2019; 8:7236-7243. [PMID: 31631570 PMCID: PMC6885891 DOI: 10.1002/cam4.2562] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2019] [Revised: 08/22/2019] [Accepted: 08/23/2019] [Indexed: 11/06/2022] Open
Abstract
BACKGROUND The prognosis of patients with recurrences from stage 4 neuroblastoma is not uniformly dismal. The evaluation of new therapies therefore needs to consider the individual risks of the treated patients. This study aims to define clinically useful risk criteria. PATIENTS AND METHODS Inclusion criteria were: first recurrence of neuroblastoma stage 4 aged ≥18 months and enrollment in first line trials between 1997 and 2016. Patients were randomized into a training set (N = 310) and an independent validation set (N = 159). The primary endpoint was secondary event-free survival. The individual treatment elements the patients received during initial and recurrent disease were analyzed as binary and time-dependent variables. A five-step multiple time-dependent Cox regression analysis was performed on the training set to identify prognostic variables adjusted for the individual frontline treatment. The selected variables resulted in a prognostic index (PI) and were used to build a risk score system. The score was validated with the validation set. RESULTS Of the 469 patients, 372 were treated with curative intent and 97 with palliative intent. The PI included the variables number of recurrence organs (hazard ratio [HR] = 2.27), time to recurrence (HR = 2.03), liver metastasis at diagnosis (HR = 1.77), first recurrence at site of the primary tumor (HR = 1.55), and age (HR = 1.29). Three risk groups were built and confirmed in the validation set. The scoring system was likewise useful for the curatively or palliatively treated subgroups. CONCLUSION A new risk score system for patients with first recurrence of stage 4 neuroblastoma aged ≥18 months at diagnosis is proposed.
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