152 results on '"Alexander Berger"'
Search Results
2. Dynamics of task preparation processes revealed by effect course analysis on response times and error rates
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Alexander Berger, Wilfried Kunde, and Markus Kiefer
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Medicine ,Science - Abstract
Abstract Cuing or executing a task impacts processing pathways for task-relevant information. While there is ample evidence that processing associated with task execution changes with practice, such evidence regarding cue-induced task preparation is scarce. Here we explored practice-related changes of processing pathways by task cuing in order to assess the plasticity of task preparation. We first developed and validated a new method for the study of practice-related changes, the effect course analysis. The effect course analysis is a model-free, non-parametric method designed to reveal effect changes within an experimental session on a continuous time scale. Then we applied this method to a new study in which cued task sets were supposed to remain activated during assessment of task-relevant pathways, as potential task execution was postponed at the end of the trial. The results showed that, with little practice, task cuing amplified task-relevant pathways, whereas this effect vanished with practice, suggesting that practice prompts fundamental changes of how task cues are used for task preparation. Hence, if one cannot be certain that cognitive processing is stationary, investigating the time course of experimental effects appears to be crucial to determine how cognitive processing is influenced by practice.
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- 2024
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3. Aon: a service to augment Alliance Genome Resource data with additional species
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Sophie K. Kearney, Alexander Berger, and Erich Baker
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Ortholog ,Homology ,AGR ,Medicine ,Biology (General) ,QH301-705.5 ,Science (General) ,Q1-390 - Abstract
Abstract Objective Cross-species comparative genomics requires access to accurate homology data across the entire range of annotated genes. The Alliance of Genome Resources (AGR) provides an open-source and comprehensive database of homology data calculated using a wide array of algorithms at differing stringencies to elucidate orthologous relationships. However, the current AGR application program interface (API) is limited to five homology endpoints for nine species. While AGR provides a robust resource for several canonical species, its utility can be greatly enhanced by increased filtering and data processing options and incorporating additional species. Results Here, we describe a novel API tool, AON, that expands access to the AGR orthology resource by creating a data structure that supports 50 additional endpoints. More importantly, it provides users with a framework for adding bespoke endpoints, custom species, and additional orthology data. We demonstrate AON’s functionality by incorporating the service into the GeneWeaver ecosystem for supporting cross-species data analysis.
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- 2023
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4. Long‐term prognostic value of vasodilator stress cardiac magnetic resonance in patients with atrial fibrillation
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Karl J. Weiss, Sarah B. Nasser, Tamar Bigvava, Adelina Doltra, Bernhard Schnackenburg, Alexander Berger, Markus S. Anker, Christian Stehning, Patrick Doeblin, Mohamed Abdelmeguid, Mohamed Talat, Rolf Gebker, Wael E‐Naggar, Burkert Pieske, and Sebastian Kelle
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Atrial fibrillation ,Perfusion ,Ischaemia ,Prognosis ,Cardiac magnetic resonance ,Late gadolinium enhancement ,Diseases of the circulatory (Cardiovascular) system ,RC666-701 - Abstract
Abstract Aims Although the prevalence of coronary artery disease (CAD) is high among patients with atrial fibrillation (AF), studies on stress perfusion cardiac magnetic resonance (CMR) imaging frequently exclude patients with AF, and its prognostic and diagnostic value in high‐risk patients with suspected or known CAD remains unclear. Methods and results In this longitudinal cohort study, we included 164 consecutive patients with AF during vasodilator perfusion CMR. Diagnostic value was evaluated regarding invasive coronary angiography in a subset of patients. We targeted a follow‐up of >5 years and used CMR results as stratification, and the primary outcome was major adverse cardiac events [MACE, cardiovascular (CV) death and myocardial infarction (MI)]. Secondary outcomes included late coronary revascularization or stroke and the components of the primary outcome. Of the whole cohort (73.8% male, mean age 72.2 years ± 7.8 SD), 99.4% were successfully scanned (163/164 patients). Median CHA2DS2‐VASc score was 4 [interquartile range (IQR) 3–5], and median 10‐year risk for CV events based on SMART risk score was high (24%, IQR 16–32%). Thirty‐two patients (19.6%) presented with ischaemia and 52 patients (31.9%) with late gadolinium enhancement (LGE). A combination of LGE and inducible ischaemia was present in 20 patients (12.3%). Diagnostic accuracy was 86.2% [confidence interval (CI) 68.3–96.1%]. The median follow‐up was 6.6 years (IQR 3.6–7.8). Ischaemia in vasodilator perfusion CMR was significantly associated with the occurrence of MACE [P
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- 2022
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5. Isolated atrial amyloidosis suspected by electrophysiological voltage mapping and diagnosed by 99mTc‐DPD scintigraphy
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Doreen Schöppenthau, Imke Schatka, Alexander Berger, Burkert Pieske, Kathrin Hahn, Fabian Knebel, Felix Kleefeld, Tobias Alexander, Jin‐Hong Gerds‐Li, and Daniel Messroghli
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HFpEF ,Isolated atrial amyloidosis ,Cardiac amyloidosis ,Nuclear imaging ,DPD scan ,Catheter ablation ,Diseases of the circulatory (Cardiovascular) system ,RC666-701 - Abstract
Abstract We present not‐yet‐seen multimodal images of a 55‐year‐old female patient with isolated atrial amyloidosis (IAA) who clinically suffered from multiple atrial arrhythmias and heart failure symptoms with preserved left ventricular ejection fraction. We aim to show structural and functional abnormalities detected by electrophysiological voltage mapping, cardiac magnetic resonance imaging (MRI) [cMRI; atrial strain measurements, late gadolinium enhancement (LGE) visualization], and 99mTc‐DPD scintigraphy. Bipolar voltage mapping performed during two electrophysiological procedures showed diffuse left atrial low‐voltage areas (bipolar
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- 2020
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6. Implementation of a Spatially-Variant and Tissue-Dependent Positron Range Correction for PET/CT Imaging
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Hunor Kertész, Thomas Beyer, Vladimir Panin, Walter Jentzen, Jacobo Cal-Gonzalez, Alexander Berger, Laszlo Papp, Peter L. Kench, Deepak Bharkhada, Jorge Cabello, Maurizio Conti, and Ivo Rausch
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positron emission tomography ,image reconstruction ,positron range correction ,PET quantification ,PRC ,Physiology ,QP1-981 - Abstract
AimTo develop and evaluate a new approach for spatially variant and tissue-dependent positron range (PR) correction (PRC) during the iterative PET image reconstruction.Materials and MethodsThe PR distributions of three radionuclides (18F, 68Ga, and 124I) were simulated using the GATE (GEANT4) framework in different material compositions (lung, water, and bone). For every radionuclide, the uniform PR kernel was created by mapping the simulated 3D PR point cloud to a 3D matrix with its size defined by the maximum PR in lung (18F) or water (68Ga and 124I) and the PET voxel size. The spatially variant kernels were composed from the uniform PR kernels by analyzing the material composition of the surrounding medium for each voxel before implementation as tissue-dependent, point-spread functions into the iterative image reconstruction. The proposed PRC method was evaluated using the NEMA image quality phantom (18F, 68Ga, and 124I); two unique PR phantoms were scanned and evaluated following OSEM reconstruction with and without PRC using different metrics, such as contrast recovery, contrast-to-noise ratio, image noise and the resolution evaluated in terms of full width at half maximum (FWHM).ResultsThe effect of PRC on 18F-imaging was negligible. In contrast, PRC improved image contrast for the 10-mm sphere of the NEMA image quality phantom filled with 68Ga and 124I by 33 and 24%, respectively. While the effect of PRC was less noticeable for the larger spheres, contrast recovery still improved by 5%. The spatial resolution was improved by 26% for 124I (FWHM of 4.9 vs. 3.7 mm).ConclusionFor high energy positron-emitting radionuclides, the proposed PRC method helped recover image contrast with reduced noise levels and with improved spatial resolution. As such, the PRC approach proposed here can help improve the quality of PET data in clinical practice and research.
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- 2022
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7. Transcatheter Restoration of the Left Ventricular Outlet in a Patient With an Implanted Apicoaortic Conduit
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Axel Unbehaun, MD, Ulrich Gerckens, MD, Christoph Klein, MD, Alexander Berger, MD, Mazen Alhaloush, MD, Jan Knierim, MD, Alexander Mladenow, MD, Natalia Solowjowa, MD, Volkmar Falk, MD, and Joerg Kempfert, MD
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aortic valve bypass ,aortic valve stenosis ,porcelain aorta ,transcatheter aortic valve replacement ,Diseases of the circulatory (Cardiovascular) system ,RC666-701 - Abstract
We describe the transcatheter management of severe aortic regurgitation in a middle-aged patient with a porcelain aorta who underwent implantation of an apicoaortic valved conduit 12 years ago. Instantaneous relief of heart failure symptoms was achieved by restoring antegrade blood flow to the ascending aorta. (Level of Difficulty: Advanced.)
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- 2020
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8. COVID-19 vs. Classical Myocarditis Associated Myocardial Injury Evaluated by Cardiac Magnetic Resonance and Endomyocardial Biopsy
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Radu Tanacli, Patrick Doeblin, Collin Götze, Victoria Zieschang, Alessandro Faragli, Christian Stehning, Grigorios Korosoglou, Jennifer Erley, Jakob Weiss, Alexander Berger, Felix Pröpper, Fridolin Steinbeis, Titus Kühne, Franziska Seidel, Dominik Geisel, Thula Cannon Walter-Rittel, Philipp Stawowy, Martin Witzenrath, Karin Klingel, Sophie Van Linthout, Burkert Pieske, Carsten Tschöpe, and Sebastian Kelle
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COVID-19 ,myocarditis ,Lake Louise Criteria ,CMR ,biopsy ,inflammation ,Diseases of the circulatory (Cardiovascular) system ,RC666-701 - Abstract
Background: Despite the ongoing global pandemic, the impact of COVID-19 on cardiac structure and function is still not completely understood. Myocarditis is a rare but potentially serious complication of other viral infections with variable recovery, and is, in some cases, associated with long-term cardiac remodeling and functional impairment.Aim: To assess myocardial injury in patients who recently recovered from an acute SARS-CoV-2 infection with advanced cardiac magnetic resonance imaging (CMR) and endomyocardial biopsy (EMB).Methods: In total, 32 patients with persistent cardiac symptoms after a COVID-19 infection, 22 patients with acute classic myocarditis not related to COVID-19, and 16 healthy volunteers were included in this study and underwent a comprehensive baseline CMR scan. Of these, 10 patients post COVID-19 and 13 with non-COVID-19 myocarditis underwent a follow-up scan. In 10 of the post-COVID-19 and 15 of the non-COVID-19 patients with myocarditis endomyocardial biopsy (EMB) with histological, immunohistological, and molecular analysis was performed.Results: In total, 10 (31%) patients with COVID-19 showed evidence of myocardial injury, eight (25%) presented with myocardial oedema, eight (25%) exhibited global or regional systolic left ventricular (LV) dysfunction, and nine (28%) exhibited impaired right ventricular (RV) function. However, only three (9%) of COVID-19 patients fulfilled updated CMR–Lake Louise criteria (LLC) for acute myocarditis. Regarding EMB, none of the COVID-19 patients but 87% of the non-COVID-19 patients with myocarditis presented histological findings in keeping with acute or chronic inflammation. COVID-19 patients with severe disease on the WHO scale presented with reduced biventricular longitudinal function, increased RV mass, and longer native T1 times compared with those with only mild or moderate disease.Conclusions: In our cohort, CMR and EMB findings revealed that SARS-CoV-2 infection was associated with relatively mild but variable cardiac involvement. More symptomatic COVID-19 patients and those with higher clinical care demands were more likely to exhibit chronic inflammation and impaired cardiac function compared to patients with milder forms of the disease.
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- 2021
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9. The Association Between Test Anxiety, Self-Efficacy, and Mental Images Among University Students: Results From an Online Survey
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Anna Maier, Caroline Schaitz, Julia Kröner, Alexander Berger, Ferdinand Keller, Petra Beschoner, Bernhard Connemann, and Zrinka Sosic-Vasic
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test anxiety ,anxiety ,self-efficacy ,mental images ,imagery ,Psychiatry ,RC435-571 - Abstract
Background and Objectives: A substantial portion of students report test anxiety, and those reporting low levels of self-efficacy seem to be especially affected. Previous research has indicated the relevance of mental images in the maintenance of anxiety disorders, however, no data are available with respect to test anxiety. In order to close this gap, the present study investigates the association between test anxiety, self-efficacy and mental images.Method: One hundred sixty-three university students completed an online survey. Test anxiety (PAF), general self-efficacy (WIRKALL-r), study-related self-efficacy (WIRK_STUD), intrusiveness of mental images (IFES), spontaneous use of imagery (SUIS) and vividness of imagery (VVIQ) were examined.Results: Test-related mental images were frequently reported among the surveyed students. Test anxiety showed a positive correlation with IFES and a negative correlation with self-efficacy. Mediation analyses showed that about one fifth of the influence of self-efficacy on test anxiety is mediated by IFES.Discussion: The present study gives first indication about an association between test anxiety, self-efficacy and mental images, even though the results are limited with respect to generalizability. Further investigations with respect to the impact of test-related mental images on the self-efficacy/test-anxiety linkage are needed.
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- 2021
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10. Cardiac Magnetic Resonance Reveals Incipient Cardiomyopathy Traits in Adult Patients With Phenylketonuria
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Radu Tanacli, Jan‐Hendrik Hassel, Rolf Gebker, Alexander Berger, Michael Gräfe, Christopher Schneeweis, Patrick Doeblin, Eckart Fleck, Christian Stehning, Frank Tacke, Burkert Pieske, Joachim Spranger, Ursula Plöckinger, Athanasia Ziagaki, and Sebastian Kelle
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cardiac magnetic resonance ,cardiomyopathy ,dyslipidemia ,phenylketonuria ,T1 native ,Diseases of the circulatory (Cardiovascular) system ,RC666-701 - Abstract
Background Phenylketonuria is the most common inborn error of amino acid metabolism, where oxidative stress and collateral metabolic abnormalities are likely to cause cardiac structural and functional modifications. We aim herein to characterize the cardiac phenotype of adult subjects with phenylketonuria using advanced cardiac imaging. Methods and Results Thirty‐nine adult patients with phenylketonuria (age, 30.5±8.7 years; 10‐year mean phenylalanine concentration, 924±330 µmol/L) and 39 age‐ and sex‐matched healthy controls were investigated. Participants underwent a comprehensive cardiac magnetic resonance and echocardiography examination. Ten‐year mean plasma levels of phenylalanine and tyrosine were used to quantify disease activity and adherence to treatment. Patients with phenylketonuria had thinner left ventricular walls (septal end‐diastolic thickness, 7.0±17 versus 8.8±1.7 mm [P1200 µmol/L (909±48 ms). Both mean phenylalanine (P=0.013) and tyrosine (P=0.035) levels were independently correlated with T1; and in a multiple regression model, higher phenylalanine levels and higher left ventricular mass associate with lower T1. Conclusions Cardiac phenotype of adult patients with phenylketonuria reveals some traits of an early‐stage cardiomyopathy. Regular cardiology follow‐up, tighter therapeutic control, and prophylaxis of cardiovascular risk factors, in particular dyslipidemia, are recommended.
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- 2021
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11. Comparison of Different Response Time Outlier Exclusion Methods: A Simulation Study
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Alexander Berger and Markus Kiefer
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response time ,reaction time ,outlier exclusion ,simulation study ,mental chronometry ,Psychology ,BF1-990 - Abstract
In response time (RT) research, RT outliers are typically excluded from statistical analysis to improve the signal-to-noise ratio. Nevertheless, there exist several methods for outlier exclusion. This poses the question, how these methods differ with respect to recovering the uncontaminated RT distribution. In the present simulation study, two RT distributions with a given population difference were simulated in each iteration. RTs were replaced by outliers following two different approaches. The first approach generated outliers at the tails of the distribution, the second one inserted outliers overlapping with the genuine RT distribution. We applied ten different outlier exclusion methods and tested, how many pairs of distributions significantly differed. Outlier exclusion methods were compared in terms of bias. Bias was defined as the deviation of the proportion of significant differences after outlier exclusion from the proportion of significant differences in the uncontaminated samples (before introducing outliers). Our results showed large differences in bias between the exclusion methods. Some methods showed a high rate of Type-I errors and should therefore clearly not be used. Overall, our results showed that applying an exclusion method based on z-scores / standard deviations introduced only small biases, while the absence of outlier exclusion showed the largest absolute bias.
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- 2021
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12. Total Synthesis of the Antimycobacterial Natural Product Chlorflavonin and Analogs via a Late-Stage Ruthenium(II)-Catalyzed ortho-C(sp2)-H-Hydroxylation
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Alexander Berger, Talea Knak, Anna-Lene Kiffe-Delf, Korana Mudrovcic, Vinayak Singh, Mathew Njoroge, Bjoern B. Burckhardt, Mohanraj Gopalswamy, Beate Lungerich, Lutz Ackermann, Holger Gohlke, Kelly Chibale, Rainer Kalscheuer, and Thomas Kurz
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Mycobacterium tuberculosis ,natural product ,flavonoid ,acetohydroxyacid synthase inhibitor ,ortho-C(sp2)-H-hydroxylation ,4H-chromen-4-one ,Medicine ,Pharmacy and materia medica ,RS1-441 - Abstract
The continuous, worldwide spread of multidrug-resistant (MDR) and extensively drug-resistant (XDR) tuberculosis (TB) endanger the World Health Organization’s (WHO) goal to end the global TB pandemic by the year 2035. During the past 50 years, very few new drugs have been approved by medical agencies to treat drug-resistant TB. Therefore, the development of novel antimycobacterial drug candidates to combat the threat of drug-resistant TB is urgent. In this work, we developed and optimized a total synthesis of the antimycobacterial natural flavonoid chlorflavonin by selective ruthenium(II)-catalyzed ortho-C(sp2)-H-hydroxylation of a substituted 3′-methoxyflavonoid skeleton. We extended our methodology to synthesize a small compound library of 14 structural analogs. The new analogs were tested for their antimycobacterial in vitro activity against Mycobacterium tuberculosis (Mtb) and their cytotoxicity against various human cell lines. The most promising new analog bromflavonin exhibited improved antimycobacterial in vitro activity against the virulent H37Rv strain of Mtb (Minimal Inhibitory Concentrations (MIC90) = 0.78 μm). In addition, we determined the chemical and metabolic stability as well as the pKa values of chlorflavonin and bromflavonin. Furthermore, we established a quantitative structure–activity relationship model using a thermodynamic integration approach. Our computations may be used for suggesting further structural changes to develop improved derivatives.
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- 2022
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13. Case Report: Early Transplant Rejection of a Methanol-Intoxicated Donor Heart in a Young Female Patient. A Diagnostic Approach With CMR, Cardiac Biopsy, and Genetic Risk Assessment
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Lukas Stoiber, Felix Schoenrath, Christoph Knosalla, Hendrik Milting, Karin Klingel, Carsten Tschöpe, Radu Tanacli, Rolf Gebker, Alexander Berger, Burkert Pieske, and Sebastian Kelle
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cardiac magnetic resonance imaging (CMR) ,heart transplantation ,gene sequence ,cardiomyopathy ,mapping - magnetic resonance imaging ,Immunologic diseases. Allergy ,RC581-607 - Abstract
This case report describes the contributions of multimodality imaging, cardiac biopsy, and genetic sequencing to the diagnosis and management of heart transplant rejection in a 23-year old patient with dilated cardiomyopathy.
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- 2021
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14. Preclinical Efficacy and Toxicity Analysis of the Pan-Histone Deacetylase Inhibitor Gossypol for the Therapy of Colorectal Cancer or Hepatocellular Carcinoma
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Mascha Mayer, Alexander Berger, Christian Leischner, Olga Renner, Markus Burkard, Alexander Böcker, Seema Noor, Timo Weiland, Thomas S. Weiss, Christian Busch, Ulrich M. Lauer, Stephan C. Bischoff, and Sascha Venturelli
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gossypol ,histone deacetylase ,epigenetics ,AT-101 ,colon cancer ,liver cancer ,Medicine ,Pharmacy and materia medica ,RS1-441 - Abstract
Gossypol, a sesquiterpenoid found in cotton seeds, exerts anticancer effects on several tumor entities due to inhibition of DNA synthesis and other mechanisms. In clinical oncology, histone deacetylase inhibitors (HDACi) are applied as anticancer compounds. In this study, we examined whether gossypol harbors HDAC inhibiting activity. In vitro analyses showed that gossypol inhibited class I, II, and IV HDAC, displaying the capability to laterally interact with the respective catalytic center and is, therefore, classified as a pan-HDAC inhibitor. Next, we studied the effects of gossypol on human-derived hepatoma (HepG2) and colon carcinoma (HCT-116) cell lines and found that gossypol induced hyperacetylation of histone protein H3 and/or tubulin within 6 h. Furthermore, incubation with different concentrations of gossypol (5–50 µM) over a time period of 96 h led to a prominent reduction in cellular viability and proliferation of hepatoma (HepG2, Hep3B) and colon carcinoma (HCT-116, HT-29) cells. In-depth analysis of underlying mechanisms showed that gossypol induced apoptosis via caspase activation. For pre-clinical evaluation, toxicity analyses showed toxic effects of gossypol in vitro toward non-malignant primary hepatocytes (PHH), the colon-derived fibroblast cell line CCD-18Co, and the intestinal epithelial cell line CCD 841 CoN at concentrations of ≥5 µM, and embryotoxicity in chicken embryos at ≥2.5 µM. In conclusion, the pronounced inhibitory capacity of gossypol on cancer cells was characterized, and pan-HDACi activity was detected in silico, in vitro, by inhibiting individual HDAC isoenzymes, and on protein level by determining histone acetylation. However, for clinical application, further chemical optimization is required to decrease cellular toxicity.
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- 2022
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15. Ground Contact Time Estimating Wearable Sensor to Measure Spatio-Temporal Aspects of Gait
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Severin Bernhart, Stefan Kranzinger, Alexander Berger, and Gerfried Peternell
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algorithm design and analysis ,gait recognition ,medical diagnosis ,motion estimation ,wearable sensors ,Chemical technology ,TP1-1185 - Abstract
Inpatient gait analysis is an essential part of rehabilitation for foot amputees and includes the ground contact time (GCT) difference of both legs as an essential component. Doctors communicate improvement advice to patients regarding their gait pattern based on a few steps taken at the doctor’s visit. A wearable sensor system, called Suralis, consisting of an inertial measurement unit (IMU) and a pressure measuring sock, including algorithms calculating GCT, is presented. Two data acquisitions were conducted to implement and validate initial contact (IC) and toe-off (TO) event detection algorithms as the basis for the GCT difference determination for able-bodied and prosthesis wearers. The results of the algorithms show a median GCT error of −51.7 ms (IMU) and 14.7 ms (sensor sock) compared to the ground truth and thus represent a suitable possibility for wearable gait analysis. The wearable system presented, therefore, enables a continuous feedback system for patients and, above all, a remote diagnosis of spatio-temporal aspects of gait behaviour based on reliable data collected in everyday life.
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- 2022
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16. Cardiac Myxomas Show Elevated Native T1, T2 Relaxation Time and ECV on Parametric CMR
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Sarah B. Nasser, Patrick Doeblin, Adelina Doltra, Bernhard Schnackenburg, Katharina Wassilew, Alexander Berger, Rolf Gebker, Tamuna Bigvava, Felix Hennig, Burkert Pieske, and Sebastian Kelle
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ECV ,T1 mapping ,T2 mapping ,CMR ,cardiac myxoma ,magnetic resonance ,Diseases of the circulatory (Cardiovascular) system ,RC666-701 - Abstract
Introduction: While cardiac tumors are rare, their identification and differentiation has wide clinical implications. Recent cardiac magnetic resonance (CMR) parametric mapping techniques allow for quantitative tissue characterization. Our aim was to examine the range of values encountered in cardiac myxomas in correlation to histological measurements.Methods and Results: Nine patients with histologically proven cardiac myxomas were included. CMR (1.5 Tesla, Philips) including parametric mapping was performed in all patients pre-operatively. All data are reported as mean ± standard deviation. Compared to myocardium, cardiac myxomas demonstrated higher native T1 relaxation times (1,554 ± 192 ms vs. 1,017 ± 58 ms, p < 0.001), ECV (46.9 ± 13.0% vs. 27.1 ± 2.6%, p = 0.001), and T2 relaxation times (209 ± 120 ms vs. 52 ± 3 ms, p = 0.008). Areas with LGE showed higher ECV than areas without (54.3 ± 17.8% vs. 32.7 ± 18.6%, p = 0.042), with differences in native T1 relaxation times (1,644 ± 217 ms vs. 1,482 ± 351 ms, p = 0.291) and T2 relaxation times (356 ± 236 ms vs. 129 ± 68 ms, p = 0.155) not reaching statistical significance.Conclusions: Parametric CMR showed elevated native T1 and T2 relaxation times and ECV values in cardiac myxomas compared to normal myocardium, reflecting an increased interstitial space and fluid content. This might help in the differentiation of cardiac myxomas from other tumor entities.
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- 2020
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17. 3D-Printed Facet Optics: Novel Adjustable Technical Optics Inspired by Compound Eyes
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Manfred Drack, Alexander Berger, Bernhard Ettinger, and Ille C. Gebeshuber
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apposition compound eyes ,biomimetics ,bioinspiration ,imaging ,fiber optics ,zooming ,Technology - Abstract
Bio-inspired by compound eyes in insects, the authors identify advantages of such an optical system and propose a novel optics that combines basic principles from compound eyes with an additional technical zooming feature. The 3D-printed, bio-inspired fiber optic set-up is based on ommatidia, the small single components of compound eyes. The advantageous aspects that are transferred from the inspiring organisms are that no focusing on objects is needed and a maximum depth of focus is always achieved. Two adjustable technical features are an adjustable field of view per pixel and a zooming possibility, not found in animals. Prototypes were produced as a proof of concept. One of them was manufactured using a stereolithography 3D printer. They were positively tested with regard to the implemented features. Optional further functionalities and developments are discussed. Possible applications of the 3D-printed, bio-inspired designs are optical devices that benefit from adjusting the field of view per pixel to zooming. Suggested are novel microscopes and screens with built-in cameras enabling online eye-to-eye communication without having to concentrate on the location of a camera.
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- 2020
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18. Systematic Review of Gossypol/AT-101 in Cancer Clinical Trials
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Olga Renner, Mascha Mayer, Christian Leischner, Markus Burkard, Alexander Berger, Ulrich M. Lauer, Sascha Venturelli, and Stephan C. Bischoff
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oral gossypol ,AT-101 ,clinical trial ,cancer ,oncologic patients ,Medicine ,Pharmacy and materia medica ,RS1-441 - Abstract
The potential of gossypol and of its R-(−)-enantiomer (R-(−)-gossypol acetic acid, AT-101), has been evaluated for treatment of cancer as an independent agent and in combination with standard chemo-radiation-therapies, respectively. This review assesses the evidence for safety and clinical effectiveness of oral gossypol/AT-101 in treating various types of cancer. The databases PubMed, MEDLINE, Cochrane, and ClinicalTrials.gov were examined. Phase I and II trials as well as single arm and randomized trials were included in this review. Results were screened to determine if they met inclusion criteria and then summarized using a narrative approach. A total of 17 trials involving 759 patients met the inclusion criteria. Overall, orally applied gossypol/AT-101 at low doses (30 mg daily or lower) was determined as well tolerable either as monotherapy or in combination with chemo-radiation. Adverse events should be strictly monitored and were successfully managed by dose-reduction or treating symptoms. There are four randomized trials, two performed in patients with advanced non-small cell lung cancer, one in subjects with head and neck cancer, and one in patients with metastatic castration-resistant prostate cancer. Thereby, standard chemotherapy (either docetaxel (two trials) or docetaxel plus cisplatin or docetaxel plus prednisone) was tested with and without AT-101. Within these trials, a potential benefit was observed in high-risk patients or in some patients with prolongation in progression-free survival or in overall survival. Strikingly, the most recent clinical trial combined low dose AT-101 with docetaxel, fluorouracil, and radiation, achieving complete responses in 11 of 13 patients with gastroesophageal carcinoma (median duration of 12 months) and a median progression-free survival of 52 months. The promising results shown in subsets of patients supports the need of further specification of AT-101 sensitive cancers as well as for the establishment of effective AT-101-based therapy. In addition, the lowest recommended dose of gossypol and its precise toxicity profile need to be confirmed in further studies. Randomized placebo-controlled trials should be performed to validate these data in large cohorts.
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- 2022
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19. 6- and 8-Prenylnaringenin, Novel Natural Histone Deacetylase Inhibitors Found in Hops, Exert Antitumor Activity on Melanoma Cells
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Sascha Venturelli, Heike Niessner, Tobias Sinnberg, Alexander Berger, Markus Burkard, Corinna Urmann, Kathrin Donaubauer, Alexander Böcker, Christian Leischner, Herbert Riepl, Jan Frank, Ulrich M Lauer, Claus Garbe, and Christian Busch
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6-prenylnaringenin ,8-prenylnaringenin ,6-PN ,8-PN ,HDAC ,Histone deacetalyse inhibition ,Melanoma ,Therapy ,Hops ,Physiology ,QP1-981 ,Biochemistry ,QD415-436 - Abstract
Background/Aims: Prenylnaringenins are natural prenylflavonoids with anticancer properties. However, the underlying mechanisms have not been elucidated yet. Here we report a novel mode of action of 6- and 8-prenylnaringenin (PN) on human melanoma cells: Inhibition of cellular histone deacetylases (HDACs). Methods: We performed in silico and in vitro analyses using 6-PN or 8-PN to study a possible interaction of 6-PN or 8-PN with HDAC as well as Western blot and FACS analyses, real-time cell proliferation and cell viability assays to assess the impact of 6-PN and 8-PN on human metastatic melanoma cells. Results: In silico, 6-PN and 8-PN fit into the binding pocket of HDAC2, 4, 7 and 8, binding to the zinc ion of their catalytic center that is essential for enzymatic activity. In vitro, 100 µmol/L of 6-PN or 8-PN inhibited all 11 conserved human HDAC of class I, II and IV. In clinical oncology HDAC inhibitors are currently investigated as new anticancer compounds. In line, treatment of SK-MEL-28 cells with 6-PN or 8-PN induced a hyperacetylation of histone complex H3 within 2 h. Further, 6-PN or 8-PN mediated a prominent, dose-dependent reduction of cellular proliferation and viability of SK-MEL-28 and BLM melanoma cells. This effect was apoptosis-independent and accompanied by down-regulation of mTOR-specific pS6 protein via pERK/pP90 in SK-MEL-28 cells. Conclusion: The identification of a broad inhibitory capacity of 6-PN and 8-PN for HDAC enzymes with antiproliferative effects on melanoma cells opens the perspective for clinical application as novel anti-melanoma drugs and the usage as innovative lead structures for chemical modification to enhance pharmacology or inhibitory activities.
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- 2018
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20. Resveratrol as a pan-HDAC inhibitor alters the acetylation status of histone [corrected] proteins in human-derived hepatoblastoma cells.
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Sascha Venturelli, Alexander Berger, Alexander Böcker, Christian Busch, Timo Weiland, Seema Noor, Christian Leischner, Sabine Schleicher, Mascha Mayer, Thomas S Weiss, Stephan C Bischoff, Ulrich M Lauer, and Michael Bitzer
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Medicine ,Science - Abstract
The polyphenolic alcohol resveratrol has demonstrated promising activities for the prevention and treatment of cancer. Different modes of action have been described for resveratrol including the activation of sirtuins, which represent the class III histone deacetylases (HDACs). However, little is known about the activity of resveratrol on the classical HDACs of class I, II and IV, although these classes are involved in cancer development or progression and inhibitors of HDACs (HDACi) are currently under investigation as promising novel anticancer drugs. We could show by in silico docking studies that resveratrol has the chemical structure to inhibit the activity of different human HDAC enzymes. In vitro analyses of overall HDAC inhibition and a detailed HDAC profiling showed that resveratrol inhibited all eleven human HDACs of class I, II and IV in a dose-dependent manner. Transferring this molecular mechanism into cancer therapy strategies, resveratrol treatment was analyzed on solid tumor cell lines. Despite the fact that hepatocellular carcinoma (HCC) is known to be particularly resistant against conventional chemotherapeutics, treatment of HCC with established HDACi already has shown promising results. Testing of resveratrol on hepatoma cell lines HepG2, Hep3B and HuH7 revealed a dose-dependent antiproliferative effect on all cell lines. Interestingly, only for HepG2 cells a specific inhibition of HDACs and in turn a histone hyperacetylation caused by resveratrol was detected. Additional testing of human blood samples demonstrated a HDACi activity by resveratrol ex vivo. Concluding toxicity studies showed that primary human hepatocytes tolerated resveratrol, whereas in vivo chicken embryotoxicity assays demonstrated severe toxicity at high concentrations. Taken together, this novel pan-HDACi activity opens up a new perspective of resveratrol for cancer therapy alone or in combination with other chemotherapeutics. Moreover, resveratrol may serve as a lead structure for chemical optimization of bioavailability, pharmacology or HDAC inhibition.
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- 2013
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21. Correction: Resveratrol as a Pan-HDAC Inhibitor Alters the Acetylation Status of Jistone Proteins in Human-Derived Hepatoblastoma Cells.
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Sascha Venturelli, Alexander Berger, Alexander Böcker, Christian Busch, Timo Weiland, Seema Noor, Christian Leischner, Sabine Schleicher, Mascha Mayer, Thomas S. Weiss, Stephan C. Bischoff, Ulrich M. Lauer, and Michael Bitzer
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Medicine ,Science - Published
- 2013
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22. Selective protection of human liver tissue in TNF-targeting of cancers of the liver by transient depletion of adenosine triphosphate.
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Timo Weiland, Kathrin Klein, Martina Zimmermann, Tobias Speicher, Sascha Venturelli, Alexander Berger, Heike Bantel, Alfred Königsrainer, Martin Schenk, Thomas S Weiss, Albrecht Wendel, Matthias Schwab, Michael Bitzer, and Ulrich M Lauer
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Medicine ,Science - Abstract
BackgroundTumor necrosis factor alpha (TNF) is able to kill cancer cells via receptor-mediated cell death requiring adenosine triphosphate (ATP). Clinical usage of TNF so far is largely limited by its profound hepatotoxicity. Recently, it was found in the murine system that specific protection of hepatocytes against TNF's detrimental effects can be achieved by fructose-mediated ATP depletion therein. Before employing this quite attractive selection principle in a first clinical trial, we here comprehensively investigated the interdependence between ATP depletion and TNF hepatotoxicity in both in vitro and ex vivo experiments based on usage of primary patient tissue materials.MethodsPrimary human hepatocytes, and both non-tumorous and tumorous patient-derived primary liver tissue slices were used to elucidate fructose-induced ATP depletion and TNF-induced cytotoxicity.ResultsPHH as well as tissue slices prepared from non-malignant human liver specimen undergoing a fructose-mediated ATP depletion were both demonstrated to be protected against TNF-induced cell death. In contrast, due to tumor-specific overexpression of hexokinase II, which imposes a profound bypass on hepatocytic-specific fructose catabolism, this was not the case for human tumorous liver tissues.ConclusionNormal human liver tissues can be protected transiently against TNF-induced cell death by systemic pretreatment with fructose used in non-toxic/physiologic concentrations. Selective TNF-targeting of primary and secondary tumors of the liver by transient and specific depletion of hepatocytic ATP opens up a new clinical avenue for the TNF-based treatment of liver cancers.
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- 2012
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23. Delayed contrast-enhanced MRI of the coronary artery wall in takayasu arteritis.
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Christopher Schneeweis, Bernhard Schnackenburg, Matthias Stuber, Alexander Berger, Udo Schneider, Jing Yu, Rolf Gebker, Robert G Weiss, Eckart Fleck, and Sebastian Kelle
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Medicine ,Science - Abstract
Takayasu arteritis (TA) is a rare form of chronic inflammatory granulomatous arteritis of the aorta and its major branches. Late gadolinium enhancement (LGE) with magnetic resonance imaging (MRI) has demonstrated its value for the detection of vessel wall alterations in TA. The aim of this study was to assess LGE of the coronary artery wall in patients with TA compared to patients with stable CAD.We enrolled 9 patients (8 female, average age 46±13 years) with proven TA. In the CAD group 9 patients participated (8 male, average age 65±10 years). Studies were performed on a commercial 3T whole-body MR imaging system (Achieva; Philips, Best, The Netherlands) using a 3D inversion prepared navigator gated spoiled gradient-echo sequence, which was repeated 34-45 minutes after low-dose gadolinium administration.No coronary vessel wall enhancement was observed prior to contrast in either group. Post contrast, coronary LGE on IR scans was detected in 28 of 50 segments (56%) seen on T2-Prep scans in TA and in 25 of 57 segments (44%) in CAD patients. LGE quantitative assessment of coronary artery vessel wall CNR post contrast revealed no significant differences between the two groups (CNR in TA: 6.0±2.4 and 7.3±2.5 in CAD; p = 0.474).Our findings suggest that LGE of the coronary artery wall seems to be common in patients with TA and similarly pronounced as in CAD patients. The observed coronary LGE seems to be rather unspecific, and differentiation between coronary vessel wall fibrosis and inflammation still remains unclear.
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- 2012
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24. Komplexe Baugruben‐ und Gründungsvarianten in einer U‐Bahn‐Schutzzone in Frankfurt
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Simon Meißner, Maximilian Kies, and Alexander Berger
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Geotechnical Engineering and Engineering Geology - Published
- 2023
25. Disconnected and Unplugged: Experiences of Technology Induced Anxieties and Tensions While Traveling.
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Cody Morris Paris, Edward Alexander Berger, Simon Rubin, and Mallory Casson
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- 2015
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26. Electrophysiological correlates of response time outliers: Outlier related potentials
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Alexander Berger and Markus Kiefer
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Neuropsychology and Physiological Psychology ,Developmental Neuroscience ,Neurology ,Endocrine and Autonomic Systems ,Cognitive Neuroscience ,General Neuroscience ,Experimental and Cognitive Psychology ,Biological Psychiatry - Published
- 2023
27. Supplementary Figure 2 from Differential Induction of Apoptosis and Senescence by the DNA Methyltransferase Inhibitors 5-Azacytidine and 5-Aza-2′-Deoxycytidine in Solid Tumor Cells
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Michael Bitzer, Ulrich M. Lauer, Ricky W. Johnstone, Bence Sipos, Simone Fulda, Helmut R. Salih, Klaus Schulze-Osthoff, Martin Schenk, Sabine Häcker, Tina Nuebling, Michaela Waibel, Frank Essmann, Timo Weiland, Alexander Berger, and Sascha Venturelli
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PDF file - 32K, Induction of apoptosis and activation of caspase 3/7 by 5-aza- CR but not 5-aza-dC in hepatoma cell lines.
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- 2023
28. Supplementary Figure 3 from Differential Induction of Apoptosis and Senescence by the DNA Methyltransferase Inhibitors 5-Azacytidine and 5-Aza-2′-Deoxycytidine in Solid Tumor Cells
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Michael Bitzer, Ulrich M. Lauer, Ricky W. Johnstone, Bence Sipos, Simone Fulda, Helmut R. Salih, Klaus Schulze-Osthoff, Martin Schenk, Sabine Häcker, Tina Nuebling, Michaela Waibel, Frank Essmann, Timo Weiland, Alexander Berger, and Sascha Venturelli
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PDF file - 18K, p53 expression of HepG2 and Hep3B cells.
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- 2023
29. Supplementary Figure 4 from Differential Induction of Apoptosis and Senescence by the DNA Methyltransferase Inhibitors 5-Azacytidine and 5-Aza-2′-Deoxycytidine in Solid Tumor Cells
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Michael Bitzer, Ulrich M. Lauer, Ricky W. Johnstone, Bence Sipos, Simone Fulda, Helmut R. Salih, Klaus Schulze-Osthoff, Martin Schenk, Sabine Häcker, Tina Nuebling, Michaela Waibel, Frank Essmann, Timo Weiland, Alexander Berger, and Sascha Venturelli
- Abstract
PDF file - 104K, 5-aza-CR induces a decrease of p53 protein levels, whereas 5-aza-dC increases -galactosidase in various tumor entities.
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- 2023
30. Supplementary Table 1 from Differential Induction of Apoptosis and Senescence by the DNA Methyltransferase Inhibitors 5-Azacytidine and 5-Aza-2′-Deoxycytidine in Solid Tumor Cells
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Michael Bitzer, Ulrich M. Lauer, Ricky W. Johnstone, Bence Sipos, Simone Fulda, Helmut R. Salih, Klaus Schulze-Osthoff, Martin Schenk, Sabine Häcker, Tina Nuebling, Michaela Waibel, Frank Essmann, Timo Weiland, Alexander Berger, and Sascha Venturelli
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PDF file - 32K, 5-aza-dC induces an increase of cellular diameter in HepG2 cells.
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- 2023
31. Supplementary Figure 1 from Differential Induction of Apoptosis and Senescence by the DNA Methyltransferase Inhibitors 5-Azacytidine and 5-Aza-2′-Deoxycytidine in Solid Tumor Cells
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Michael Bitzer, Ulrich M. Lauer, Ricky W. Johnstone, Bence Sipos, Simone Fulda, Helmut R. Salih, Klaus Schulze-Osthoff, Martin Schenk, Sabine Häcker, Tina Nuebling, Michaela Waibel, Frank Essmann, Timo Weiland, Alexander Berger, and Sascha Venturelli
- Abstract
PDF file - 157K, Change of cytokine release of HepG2 cells under treatment.
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- 2023
32. Supplementary Figure Legend from Differential Induction of Apoptosis and Senescence by the DNA Methyltransferase Inhibitors 5-Azacytidine and 5-Aza-2′-Deoxycytidine in Solid Tumor Cells
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Michael Bitzer, Ulrich M. Lauer, Ricky W. Johnstone, Bence Sipos, Simone Fulda, Helmut R. Salih, Klaus Schulze-Osthoff, Martin Schenk, Sabine Häcker, Tina Nuebling, Michaela Waibel, Frank Essmann, Timo Weiland, Alexander Berger, and Sascha Venturelli
- Abstract
PDF file - 28K
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- 2023
33. Data from Differential Induction of Apoptosis and Senescence by the DNA Methyltransferase Inhibitors 5-Azacytidine and 5-Aza-2′-Deoxycytidine in Solid Tumor Cells
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Michael Bitzer, Ulrich M. Lauer, Ricky W. Johnstone, Bence Sipos, Simone Fulda, Helmut R. Salih, Klaus Schulze-Osthoff, Martin Schenk, Sabine Häcker, Tina Nuebling, Michaela Waibel, Frank Essmann, Timo Weiland, Alexander Berger, and Sascha Venturelli
- Abstract
Epigenetic alterations are a hallmark of cancer that govern the silencing of genes. Up to now, 5-azacytidine (5-aza-CR, Vidaza) and 5-aza-2′-deoxycytidine (5-aza-dC, Dacogen) are the only clinically approved DNA methyltransferase inhibitors (DNMTi). Current effort tries to exploit DNMTi application beyond acute leukemia or myelodysplastic syndrome, especially to solid tumors. Although both drugs only differ by a minimal structural difference, they trigger distinct molecular mechanisms that are highly relevant for a rational choice of new combination therapies. Therefore, we investigated cell death pathways in vitro in human hepatoma, colon, renal, and lung cancer cells and in vivo in chorioallantoic membrane and xenograft models. Real-time cancer cell monitoring and cytokine profiling revealed a profoundly distinct response pattern to both drugs. 5-aza-dC induced p53-dependent tumor cell senescence and a high number of DNA double-strand breaks. In contrast, 5-aza-CR downregulated p53, induced caspase activation and apoptosis. These individual response patterns of tumor cells could be verified in vivo in chorioallantoic membrane assays and in a hepatoma xenograft model. Although 5-aza-CR and 5-aza-dC are viewed as drugs with similar therapeutic activity, they induce a diverse molecular response in tumor cells. These findings together with other reported differences enable and facilitate a rational design of new combination strategies to further exploit the epigenetic mode of action of these two drugs in different areas of clinical oncology. Mol Cancer Ther; 12(10); 2226–36. ©2013 AACR.
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- 2023
34. Exploring the Role of Facebook in Re-Shaping Backpacker's Social Interactions.
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Edward Alexander Berger and Cody Morris Paris
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- 2014
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35. Academic training increases grounding of scientific concepts in experiential brain systems
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Martin Ulrich, Marcel Harpaintner, Natalie M Trumpp, Alexander Berger, and Markus Kiefer
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Cellular and Molecular Neuroscience ,Cognitive Neuroscience - Abstract
Scientific concepts typically transcendent our sensory experiences. Traditional approaches to science education therefore assume a shift towards amodal or verbal knowledge representations during academic training. Grounded cognition approaches, in contrast, predict a maintenance of grounding of the concepts in experiential brain networks or even an increase. To test these competing approaches, the present study investigated the semantic content of scientific psychological concepts and identified the corresponding neural circuits using functional magnetic resonance imaging (fMRI) in undergraduate psychology students (beginners) and in graduated psychologists (advanced learners). During fMRI scanning, participants were presented with words denoting scientific psychological concepts within a lexical decision task (e.g. “conditioning”, “habituation”). The individual semantic property content of each concept was related to brain activity during abstract concept processing. In both beginners and advanced learners, visual and motor properties activated brain regions also involved in perception and action, while mental state properties increased activity in brain regions also recruited by emotional–social scene observation. Only in advanced learners, social constellation properties elicited brain activity overlapping with emotional–social scene observation. In line with grounded cognition approaches, the present results highlight the importance of experiential information for constituting the meaning of abstract scientific concepts during the course of academic training.
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- 2022
36. The Influence of the BDNF Val66Met Polymorphism on Mechanisms of Semantic Priming: Analyses with Drift-Diffusion Models of Masked and Unmasked Priming
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Markus Kiefer, Simon Sanwald, Christian Montag, and Alexander Berger
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Psychiatry and Mental health ,Clinical Psychology ,General Neuroscience ,Attentional modulation ,Lexical decision task ,Val66met polymorphism ,Experimental and Cognitive Psychology ,Psychology (miscellaneous) ,Neuroscience ,Priming (psychology) ,Applied Psychology ,Stroop effect ,Mathematics - Abstract
Automatic and strategic processes in semantic priming can be investigated with masked and unmasked priming tasks. Unmasked priming is thought to enable strategic processes due to the conscious processing of primes, while masked priming exclusively depends on automatic processes due to the invisibility of the prime. Besides task properties, interindividual differences may alter priming effects. In a recent study, masked and unmasked priming based on mean response time (RT) and error rate (ER) differed as a function of the BDNF Val66Met polymorphism (Sanwald et al., 2020). The BDNF Val66Met polymorphism is related to the integrity of several cognitive executive functions and might thus influence the magnitude of priming. In the present study, we reanalyzed this data with drift-diffusion models. Drift-diffusion models conjointly analyze single trial RT and ER data and serve as a framework to elucidate cognitive processes underlying priming. Masked and unmasked priming effects were observed for the drift rates ν, presumably reflecting semantic preactivation. Priming effects on nondecision time t0 were especially pronounced in unmasked priming, suggesting additional conscious processes to be involved in the t0 modulation. Priming effects on the decision thresholds a may reflect a speed-accuracy tradeoff. Considering the BDNF Val66Met polymorphism, we found lowered drift rates and decision thresholds for Met allele carriers, possibly reflecting a superficial processing style in Met allele carriers. The present study shows that differences in cognitive tasks between genetic groups can be elucidated using drift-diffusion modeling.
- Published
- 2021
37. Transcatheter Restoration of the Left Ventricular Outlet in a Patient With an Implanted Apicoaortic Conduit
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Jan Knierim, Christoph Klein, Mazen Alhaloush, Joerg Kempfert, Axel Unbehaun, Alexander Berger, Ulrich Gerckens, Volkmar Falk, Natalia Solowjowa, and Alexander Mladenow
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0301 basic medicine ,medicine.medical_specialty ,Case Report ,aortic valve stenosis ,Regurgitation (circulation) ,030105 genetics & heredity ,Valved conduit ,porcelain aorta ,03 medical and health sciences ,0302 clinical medicine ,Clinical Case ,dPmean, mean transvalvular pressure gradient ,medicine ,Diseases of the circulatory (Cardiovascular) system ,NYHA, New York Heart Association ,AVB, aortic valve bypass ,Apicoaortic Conduit ,TAVR, transcatheter aortic valve replacement ,business.industry ,medicine.disease ,Surgery ,DLZ, device landing zone ,TTE, transthoracic echocardiography ,RC666-701 ,Aortic valve stenosis ,cardiovascular system ,transcatheter aortic valve replacement ,TAVR -transcatheter aortic valve replacement ,aortic valve bypass ,Cardiology and Cardiovascular Medicine ,Porcelain aorta ,business ,030217 neurology & neurosurgery - Abstract
We describe the transcatheter management of severe aortic regurgitation in a middle-aged patient with a porcelain aorta who underwent implantation of an apicoaortic valved conduit 12 years ago. Instantaneous relief of heart failure symptoms was achieved by restoring antegrade blood flow to the ascending aorta. (Level of Difficulty: Advanced.), Graphical abstract
- Published
- 2020
38. Isolated atrial amyloidosis suspected by electrophysiological voltage mapping and diagnosed by 99m Tc‐DPD scintigraphy
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Imke Schatka, Burkert Pieske, Felix Kleefeld, Daniel Messroghli, Alexander Berger, Fabian Knebel, Jin-Hong Gerds-Li, Tobias Alexander, Doreen Schöppenthau, and Kathrin Hahn
- Subjects
medicine.medical_specialty ,medicine.medical_treatment ,Case Report ,Catheter ablation ,Case Reports ,Cardiac amyloidosis ,030204 cardiovascular system & hematology ,Scintigraphy ,03 medical and health sciences ,0302 clinical medicine ,Cardiac magnetic resonance imaging ,Internal medicine ,medicine ,Voltage mapping ,Diseases of the circulatory (Cardiovascular) system ,Isolated atrial amyloidosis ,cardiovascular diseases ,030212 general & internal medicine ,DPD scan ,Fibrotic atrial cardiomyopathy ,Ejection fraction ,medicine.diagnostic_test ,business.industry ,Amyloidosis ,HFpEF ,medicine.disease ,RC666-701 ,Heart failure ,cardiovascular system ,Cardiology ,Atrial substrate ,Cardiology and Cardiovascular Medicine ,business ,Nuclear imaging - Abstract
We present not‐yet‐seen multimodal images of a 55‐year‐old female patient with isolated atrial amyloidosis (IAA) who clinically suffered from multiple atrial arrhythmias and heart failure symptoms with preserved left ventricular ejection fraction. We aim to show structural and functional abnormalities detected by electrophysiological voltage mapping, cardiac magnetic resonance imaging (MRI) [cMRI; atrial strain measurements, late gadolinium enhancement (LGE) visualization], and 99mTc‐DPD scintigraphy. Bipolar voltage mapping performed during two electrophysiological procedures showed diffuse left atrial low‐voltage areas (bipolar
- Published
- 2020
39. The Innsbruck Domestic Violence screening questions (IDV-3) effectively help to identify victims of domestic violence during clinical routine - Results of an observational single-center study
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Thomas Beck, Alexander Berger, Lydia Stix, and David Riedl
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Psychiatry and Mental health ,Domestic Violence ,Humans ,Mass Screening - Published
- 2022
40. What should we agree on about the repugnant conclusion?
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Kevin Kuruc, Michelle Hutchinson, H. Orri Stefánsson, Clinton Castro, Michal Masny, Nick Beckstead, William MacAskill, Susumu Cato, Hilary Greaves, Katie Steele, Diane Coffey, Dean Spears, Tim S. Campbell, Christian Tarsney, Marc Fleurbaey, John Broome, Torbjörn Tännsjö, Geir B. Asheim, Jeff Sebo, Marcus Pivato, Lisa Forsberg, Toby Ord, Stéphane Zuber, Nikhil Venkatesh, Alexander Berger, Johan E. Gustafsson, Mark Budolfson, Nicholas Lawson, Yew-Kwang Ng, Centre d'économie de la Sorbonne (CES), Université Paris 1 Panthéon-Sorbonne (UP1)-Centre National de la Recherche Scientifique (CNRS), Paris School of Economics (PSE), École des Ponts ParisTech (ENPC)-École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris 1 Panthéon-Sorbonne (UP1)-Centre National de la Recherche Scientifique (CNRS)-École des hautes études en sciences sociales (EHESS)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), University of Texas at Austin [Austin], Théorie économique, modélisation et applications (THEMA), CY Cergy Paris Université (CY)-Centre National de la Recherche Scientifique (CNRS), ANR-17-EURE-0001,PGSE,Ecole d'Economie de Paris(2017), and Centre National de la Recherche Scientifique (CNRS)-CY Cergy Paris Université (CY)
- Subjects
Filosofi ,education.field_of_study ,Sociology and Political Science ,05 social sciences ,Population ,[SHS.PHIL]Humanities and Social Sciences/Philosophy ,Environmental ethics ,06 humanities and the arts ,B Philosophy (General) ,[SHS.DEMO]Humanities and Social Sciences/Demography ,0603 philosophy, ethics and religion ,[SHS.ECO]Humanities and Social Sciences/Economics and Finance ,Population ethics ,Philosophy ,Quality of life (healthcare) ,060302 philosophy ,0502 economics and business ,JEL: Z - Other Special Topics/Z.Z1 - Cultural Economics • Economic Sociology • Economic Anthropology/Z.Z1.Z13 - Economic Sociology • Economic Anthropology • Social and Economic Stratification ,050206 economic theory ,Sociology ,education - Abstract
The Repugnant Conclusion is an implication of some approaches to population ethics. It states, in Derek Parfit's original formulation, For any possible population of at least ten billion people, all with a very high quality of life, there must be some much larger imaginable population whose existence, if other things are equal, would be better, even though its members have lives that are barely worth living. (Parfit 1984: 388)
- Published
- 2021
41. Stress myocardial blood flow reduced after severe COVID-19, not related to symptoms
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P. Doeblin, Ebraham Alskaf, F Steinbeis, Sebastian Kelle, Martin Witzenrath, S Al-Tabatabaee, B. Pieske, Amedeo Chiribiri, A. Faragli, Cian M. Scannell, C Goetze, Alexander Berger, and Christian Stehning
- Subjects
Stress (mechanics) ,medicine.medical_specialty ,Coronavirus disease 2019 (COVID-19) ,business.industry ,Internal medicine ,Cardiology ,Medicine ,Blood flow ,Cardiology and Cardiovascular Medicine ,business - Abstract
Introduction Persistent cardiopulmonary symptoms after COVID-19 are reported in a large number of patients and the underlying pathology is still poorly understood. (1) Histopathologic studies revealed myocardial macrophage infiltrates in deceased patients, likely an unspecific finding of severe illness, and increased prevalence of micro- and macrovascular thrombi. (2) We examined whether microvascular perfusion, measured by quantitative cardiac magnetic resonance under vasodilator stress, was altered post COVID-19. Methods Our population consisted of 12 patients from the Pa-COVID-19-Study of the Charité Berlin, which received a cardiac MRI as part of a systematic follow up post discharge, 10 patients that presented at the German Heart Center Berlin with persistent cardiac symptoms post COVID-19 and 12 patients from the Kings College London referred for stress MRI and previous COVID-19. The scan protocol included standard functional, edema and scar imaging and quantitative stress and rest perfusion to assess both macro- and microvascular coronary artery disease. The pharmacological stress agent was regadenosone in 20 and adenosine in 13 of the patients. To control for the higher heart rate increase under regadenosone compared to adenosine, we calculated the myocardial blood flow per heartbeat (MBF_HRi) under stress. Results The median time between first positive PCR for COVID-19 and the CMR exam was 2 months (Range 0 to 12). None of the 33 patients exhibited signs of myocardial edema. One patient with a previous history of myocarditis had focal fibrosis. Three patients with known coronary artery disease showed ischemic Late Enhancement. Five patients had a small pericardial effusion; one of these four patients showed slight focal pericardial edema and LGE, consistent with mild focal pericarditis. Five Patients had a stress-induced focal perfusion deficit. Mean Stress MBF_HRi was 32.5±6.5 μl/beat/g. Stress MBF_HRi was negatively correlated with COVID-19 severity (rho=−0.361, P=0.039) and age (r=−0.452, P=0.009). The correlation with COVID-19 severity remained significant after controlling for age (rho=−0.390, P=0.027). There was no apparent difference in stress MBF_HRi between patients with and without persistent chest pain (34.5 vs. 31.5 μl/beat/g, P=0.229) Conclusion While vasodilator-stress myocardial blood flow after COVID-19 was negatively correlated to COVID-19 severity, it was not correlated to the presence of chest pain. The etiology of persistent cardiac symptoms after COVID-19 remains unclear. Funding Acknowledgement Type of funding sources: Private company. Main funding source(s): Philips Figure 1. A) Quantitative regadenosone stress myocardial blood flow (MBF) map, medial short axis slice, in a patient with persistent cardiac symptoms after COVID-19. B) Boxplot of stress MBF per heart beat by COVID-19 severity, showing decreasing MBF with increasing COVID-19 severity.
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- 2021
42. Cardiac Magnetic Resonance Reveals Incipient Cardiomyopathy Traits in Adult Patients With Phenylketonuria
- Author
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Ursula Plöckinger, Athanasia Ziagaki, Sebastian Kelle, Eckart Fleck, Jan-Hendrik Hassel, Patrick Doeblin, Frank Tacke, Rolf Gebker, Joachim Spranger, Michael Gräfe, Radu Tanacli, Burkert Pieske, Alexander Berger, Christian Stehning, and Christopher Schneeweis
- Subjects
Adult ,medicine.medical_specialty ,Magnetic Resonance Spectroscopy ,Phenylalanine ,Cardiomyopathy ,phenylketonuria ,medicine.disease_cause ,cardiac magnetic resonance ,Imaging ,Young Adult ,Internal medicine ,Phenylketonurias ,medicine ,Humans ,Diseases of the circulatory (Cardiovascular) system ,Amino acid metabolism ,T1 native ,Original Research ,Heart Failure ,Metabolic Syndrome ,Adult patients ,business.industry ,dyslipidemia ,medicine.disease ,Phenotype ,RC666-701 ,Cardiology ,Tyrosine ,Cardiology and Cardiovascular Medicine ,business ,Cardiac magnetic resonance ,Cardiomyopathies ,cardiomyopathy ,Dyslipidemia ,Oxidative stress - Abstract
Background Phenylketonuria is the most common inborn error of amino acid metabolism, where oxidative stress and collateral metabolic abnormalities are likely to cause cardiac structural and functional modifications. We aim herein to characterize the cardiac phenotype of adult subjects with phenylketonuria using advanced cardiac imaging. Methods and Results Thirty‐nine adult patients with phenylketonuria (age, 30.5±8.7 years; 10‐year mean phenylalanine concentration, 924±330 µmol/L) and 39 age‐ and sex‐matched healthy controls were investigated. Participants underwent a comprehensive cardiac magnetic resonance and echocardiography examination. Ten‐year mean plasma levels of phenylalanine and tyrosine were used to quantify disease activity and adherence to treatment. Patients with phenylketonuria had thinner left ventricular walls (septal end‐diastolic thickness, 7.0±17 versus 8.8±1.7 mm [ P P =0.004]), more dilated left ventricular cavity (end‐diastolic volume, 87±14 versus 80±14 mL/m 2 [ P =0.0178]; end‐systolic volume, 36±9 versus 29±8 mL/m 2 [ P P P =0.027]), and lower left ventricular mass (38.2±7.9 versus 47.8±11.0 g/m 2 [ P P 1200 µmol/L (909±48 ms). Both mean phenylalanine ( P =0.013) and tyrosine ( P =0.035) levels were independently correlated with T1; and in a multiple regression model, higher phenylalanine levels and higher left ventricular mass associate with lower T1. Conclusions Cardiac phenotype of adult patients with phenylketonuria reveals some traits of an early‐stage cardiomyopathy. Regular cardiology follow‐up, tighter therapeutic control, and prophylaxis of cardiovascular risk factors, in particular dyslipidemia, are recommended.
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- 2021
43. Review of safety reports of cardiac MR-imaging in patients with recently implanted coronary artery stents at various field strengths
- Author
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Alexander Berger, Burkert Pieske, Christian Stehning, Christian David Schenk, Rolf Gebker, and Sebastian Kelle
- Subjects
medicine.medical_specialty ,medicine.medical_treatment ,Biomedical Engineering ,Coronary Artery Disease ,030204 cardiovascular system & hematology ,Coronary artery disease ,03 medical and health sciences ,0302 clinical medicine ,Medicine ,Stent implantation ,Humans ,In patient ,business.industry ,Stent ,General Medicine ,medicine.disease ,Mr imaging ,Coronary Vessels ,Magnetic Resonance Imaging ,Re stenosis ,medicine.anatomical_structure ,Treatment Outcome ,Surgery ,Stents ,Radiology ,business ,030217 neurology & neurosurgery ,Artery - Abstract
Background: Aim of this study was to review current literature and data regarding the effects of MRI-examination post stent implantation on re-occlusion rates. Methods: We focused on representative...
- Published
- 2020
44. Cardiac Magnetic Resonance Reveals Incipient Cardiomyopathy Traits in Adult Patients with Phenylketonuria
- Author
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Bernhard Schnackenburg, Frank Tacke, Burkert Pieske, Ursula Plöckinger, Jan-Hendrik Hassel, Athanasia Ziagaki, Eckart Fleck, Michael Gräfe, Radu Tanacli, Alexander Berger, Rolf Gebker, Sebastian Kelle, and Christopher Schneeweis
- Subjects
medicine.medical_specialty ,medicine.diagnostic_test ,business.industry ,Neuropsychology ,Diastole ,Cardiomyopathy ,Disease ,medicine.disease ,Cardiac magnetic resonance imaging ,Internal medicine ,medicine ,Cardiology ,Stage (cooking) ,business ,Dyslipidemia ,Cardiac imaging - Abstract
Background: Phenylketonuria (PKU) is the most common inborn error of amino-acid metabolism, which, when untreated results to severe neuropsychological complications. . New born screenings programs and immediate beginning of phenylalanine-restricted diet, greatly ameliorate the prognosis. However, previous studies have shown that PKU patients have elevated levels of oxidative stress and collateral metabolic abnormalities such as dyslipidemia, predisposing to cardiovascular disease. The purpose of this study was to characterize the cardiac phenotype of adult subjects with PKU using advanced cardiac imaging. Methods: Thirty-nine adult patients with PKU (age 30.5±8.7 year old, median 10 year phenylalanine concentration (Phe) 924±330 µmol/L) and thirty-nine age- and gender- matched healthy controls were investigated. Participants underwent a comprehensive cardiac magnetic resonance imaging (CMR) and echocardiography examination to determine systolic and diastolic left (LV) and right (RV) ventricular function, LV mass, ventricular fibrosis, left atrial function and aortic distensibility. CMR parametric mapping was used to characterize structural tissue modification. All available quarterly plasma levels of Phe and tyrosine (Tyr) levels were averaged for 10 years prior to the CMR scan to evaluate therapeutic efficacy and compliance. Results: PKU patients had thinner LV walls (Septal end-diastolic (ED) thickness 7.0±17 vs 8.8±1.7 mm, p 1200µmol/L (909±48 ms). Both mean Phe (p=0.013) and Tyr (p=0.035) concentration levels were independently predictive for lower T1 values in a regression model. Conclusion: Taken together our findings indicate an early stage LV dysfunction in patients with PKU which associates lower T1 native levels probably reflecting an infiltration with lipids of the myocardium. These results suggest the importance of regular cardiac follow-up in clinical monitoring of the adult subjects with PKU. Funding Statement: Sebastian Kelle is supported by a grant from Philips Healthcare and received funding from the DZHK (German Centre for Cardiovascular Research) and by the BMBF (German Ministry of Education and Research). Declaration of Interests: None of the other authors reports a relationship with industry and other relevant entities – financial or otherwise – that might pose a conflict of interest in connection with the submitted article. The following authors report financial activities outside the submitted work: Radu Tanacli reports no conflict of interest. Burkert Pieske reports having received consultancy and lecture honoraria from Bayer Daiichi Sankyo, MSD, Novartis, Sanofi-Aventis, Stealth Peptides and Vifor Pharma; and editor honoraria from the Journal of the American College of Cardiology. Radu Tanacli and the other co-authors report no conflict of interest. Ethics Approval Statement: The study was approved by the Ethics Committee of the Charite University of Medicine in Berlin, complied with the Declaration of Helsinki and was registered at the German Register for Clinical Studies (DRKS00001120).
- Published
- 2020
45. Why the EU and NATO have failed to manage the Russia-Ukraine Crisis?
- Author
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Alexander Berger
- Subjects
Political science - Abstract
The world observed a well-developed Russian strategy and military model have had destabilizing consequences and wide-ranging implications for international security, in particular for Europe, and global stability since the Ukraine crisis. Needless to say, most European countries and notably NATO conclude that Russian policy, military strategy, and military practice in the Ukraine crisis challenge the European security and carry significant implications for NATO, therefore the Ukraine crisis force the EU and NATO to concentrate on measures against Russian strategy.[1] In reality, Russia has already given the signals of its intentions via the Military Doctrine 2010 and Defense Strategy 2013 that list destabilization of the near abroad, in other words buffer zone, and NATO or the EU expansion, including deployment of military forces, as most relevant military threats. Both documents highlight that “Russia faced the very real threat of being side-lined in international affairs.” [2] Furthermore MacKinnon suggests that in line with its new regime change strategy, the United States forced the former Soviet Union’s member states to establish their political institutions, provided funds for the opposition, and supported revolutions in Georgia, Ukraine, and Kyrgyzstan. Thus, the revolutions added to the Kremlin’s perception that “Washington’s chief objective might have been to change the regime in Russia as well.”[3] Likewise, Russian Foreign Minister Sergei Lavrov said “NATO’s expansion by pulling more Russia’s neighboring countries into the alliance is unacceptable”.[4] Therefore it could be concluded from Russian point of view that everything should be done to prevent NATO and the EU expansion which can be characterized as the greatest threat to Russian security, and that’s why Russia must restore its status as a great power inside its own sphere of influence. It is the aim of this analytic paper to search why the EU and NATO have failed to manage the crisis emanating from Russian aggression and expansion in Ukraine, and to address the current strategic environment as well. I shall try to analyze the drivers and the reasons of NATO and the EU’s poor reaction against Russia, and finally I will emphasize why and how the roles of NATO and the European Security Strategy should be reconsidered in the light of energy security policy of the EU, and why NATO and the EU needs to improve their responsiveness rather than readiness.
- Published
- 2018
46. Chemovirotherapy for pancreatic cancer: Gemcitabine plus oncolytic measles vaccine virus
- Author
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Markus Burkard, Christian Leischner, Sascha Venturelli, Verena May, Ulrich M. Lauer, Alexander Berger, Nisar P. Malek, and Susanne Berchtold
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0301 basic medicine ,Cancer Research ,business.industry ,Cancer ,Articles ,Cell cycle ,medicine.disease ,Gemcitabine ,Virus ,Oncolytic virus ,03 medical and health sciences ,030104 developmental biology ,0302 clinical medicine ,Oncology ,Viral replication ,030220 oncology & carcinogenesis ,Pancreatic cancer ,medicine ,Cancer research ,Virotherapy ,business ,medicine.drug - Abstract
Oncolytic virotherapy with vaccine viruses employs replicative vectors, which quite selectively infect tumor cells leading to massive virus replication followed by subsequent profound tumor cell death (oncolysis). Measles vaccine virus (MeV) has already shown great oncolytic activity against different types of cancers, including pancreatic cancer. Gemcitabine is a first line chemotherapeutic drug used for pancreatic cancer in palliative treatment plans. Furthermore, this drug can be used to induce senescence, a permanent cell cycle arrest, in tumor cells. In our preclinical work, three well-characterized immortalized human pancreatic cancer cell lines were used to investigate the combinatorial effect of MeV-based virotherapy together with the chemotherapeutic compound gemcitabine. Viability assays revealed that the combination of only small amounts of MeV together with subtherapeutic concentrations of gemcitabine resulted in a tumor cell mass reduction of >50%. To further investigate the replication of the oncolytic MeV vectors under these distinct combinatorial conditions, viral growth curves were generated. As a result, viral replication was found to be only slightly diminished in the presence of gemcitabine. As gemcitabine induces senescence, the effect of MeV on that phenomenon was explored using a senescence-associated β-galactosidase assay. Notably, gemcitabine-induced tumor cell senescence was not impaired by MeV. Accordingly, the chemovirotherapeutic combination of gemcitabine plus oncolytic MeV constitutes a novel therapeutic option for advanced pancreatic carcinoma that is characterized by the mutual improvement of the effectiveness of each therapeutic component.
- Published
- 2019
47. Curating gene sets: challenges and opportunities for integrative analysis
- Author
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Alexander Berger, Jason A. Bubier, Jake Emerson, Timothy Reynolds, David P. Hill, Gaurab Mukherjee, Erich J. Baker, Judith A. Blake, and Elissa J. Chesler
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Jaccard index ,Computer science ,Interface (Java) ,Context (language use) ,Information repository ,General Biochemistry, Genetics and Molecular Biology ,Workflow ,03 medical and health sciences ,Stress, Physiological ,Databases, Genetic ,Data Curation ,030304 developmental biology ,Biological Phenomena ,0303 health sciences ,Data curation ,Suite ,030302 biochemistry & molecular biology ,Gene sets ,Data science ,ComputingMethodologies_PATTERNRECOGNITION ,Genes ,Data_GENERAL ,Original Article ,ComputingMethodologies_GENERAL ,General Agricultural and Biological Sciences ,Software ,Information Systems - Abstract
Genomic data interpretation often requires analyses that move from a gene-by-gene focus to a focus on sets of genes that are associated with biological phenomena such as molecular processes, phenotypes, diseases, drug interactions or environmental conditions. Unique challenges exist in the curation of gene sets beyond the challenges in curation of individual genes. Here we highlight a literature curation workflow whereby gene sets are curated from peer-reviewed published data into GeneWeaver (GW), a data repository and analysis platform. We describe the system features that allow for a flexible yet precise curation procedure. We illustrate the value of curation by gene sets through analysis of independently curated sets that relate to the integrated stress response, showing that sets curated from independent sources all share significant Jaccard similarity. A suite of reproducible analysis tools is provided in GW as services to carry out interactive functional investigation of user-submitted gene sets within the context of over 150 000 gene sets constructed from publicly available resources and published gene lists. A curation interface supports the ability of users to design and maintain curation workflows of gene sets, including assigning, reviewing and releasing gene sets within a curation project context.
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- 2019
48. Data-driven, projection-based respiratory motion compensation of PET data for cardiac PET/CT and PET/MR imaging
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Martin Lyngby, Lassen, Thomas, Beyer, Alexander, Berger, Dietrich, Beitzke, Sazan, Rasul, Florian, Büther, Marcus, Hacker, and Jacobo, Cal-González
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Aged, 80 and over ,Male ,Phantoms, Imaging ,Systole ,Movement ,Myocardium ,Respiration ,Reproducibility of Results ,Heart ,Stroke Volume ,Magnetic Resonance Imaging ,Ventricular Function, Left ,Electrocardiography ,Diastole ,Fluorodeoxyglucose F18 ,Positron Emission Tomography Computed Tomography ,Image Processing, Computer-Assisted ,Humans ,Computer Simulation ,Female ,Aged - Abstract
Respiratory patient motion causes blurring of the PET images that may impact accurate quantification of perfusion and infarction extents in PET myocardial viability studies. In this study, we investigate the feasibility of correcting for respiratory motion directly in the PET-listmode data prior to image reconstruction using a data-driven, projection-based, respiratory motion compensation (DPR-MoCo) technique.The DPR-MoCo method was validated using simulations of a XCAT phantom (Biograph mMR PET/MR) as well as experimental phantom acquisitions (Biograph mCT PET/CT). Seven patient studies following a dual-tracer (The DPR-MoCo and the No-MoCo images presented with similar noise-properties (CoV) (P = .12), while the RTA-MoCo and reference-gate images showed increased noise levels (P = .05). TBRThe projection-based DPR-MoCo method helps to improve PET image quality of the myocardium without the need for external devices for motion tracking.
- Published
- 2018
49. High-dose dobutamine stress steady-state free precession (SSFP) cine MRI at 3T with patient adaptive local radiofrequency (RF) shimming using dual-source RF transmission
- Author
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Christopher Schneeweis, Alexander Berger, Christoph Klein, Rolf Gebker, Marc Kouwenhoven, Eckart Fleck, Sebastian Kelle, and Bernhard Schnackenburg
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medicine.diagnostic_test ,Image quality ,business.industry ,Magnetic resonance imaging ,Steady-state free precession imaging ,Dobutamine stress ,medicine.disease ,Coronary artery disease ,Flip angle ,medicine ,Radiology, Nuclear Medicine and imaging ,Dobutamine ,Nuclear medicine ,business ,Electrocardiography ,medicine.drug - Abstract
Purpose To prospectively assess the feasibility, image quality, and diagnostic accuracy of high-dose dobutamine stress magnetic resonance imaging (DSMR) using steady-state free precession (SSFP) cine imaging at 3T applying a dual-source radiofrequency (RF) excitation magnetic resonance imaging (MRI) system with parallel transmission and patient adaptive local RF shimming. Materials and Methods DSMR using SSFP cine imaging was performed in 44 patients at 3T scheduled for a clinically indicated coronary angiography. The effect of conventional versus dual-source RF transmission was assessed regarding homogeneity of the B1 field, contrast-to-noise ratios (CNRs) at rest, image quality, and diagnostic accuracy of DSMR using long and short axis. Results The mean percentage of the intended flip angle within the heart increased from 88 ± 9.1% with single-source to 103 ± 5.6% (P < 0.001) dual-source RF transmission. CNR increased for dual-source particularly at the apex (63.4 ± 24.2 vs. 36.5 ± 16.5, P < 0.001) but also at the base of the left ventricle (LV) (50.1 ± 14.8 vs. 39.3 ± 15.8, P < 0.001). Image quality of dual-source was higher both at rest (2.8 ± 0.5 vs. 2.6 ± 0.7, P < 0.001) and stress (2.5 ± 0.7 vs. 2.0 ± 1.0, P < 0.001). The number of segments with severe artifacts or nondiagnostic image quality at stress was lower with dual-source RF transmission (8% vs. 27%, P < 0.001). The diagnostic accuracy of DSMR in coronary territories using dual-source RF transmission was significantly higher (77% vs. 65%, P = 0.04). Conclusion Patient adaptive local RF shimming using dual-source RF transmission provided significantly improved image quality and higher diagnostic accuracy of SSFP during DSMR at 3T compared to conventional RF transmission. J. Magn. Reson. Imaging 2015;42:746–753.
- Published
- 2015
50. Isolated atrial amyloidosis suspected by electrophysiological voltage mapping and diagnosed by 99mTc‐DPD scintigraphy.
- Author
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Doreen, Schöppenthau, Imke, Schatka, Alexander, Berger, Burkert, Pieske, Hahn, Kathrin, Fabian, Knebel, Felix, Kleefeld, Alexander, Tobias, Jin‐Hong, Gerds‐Li, and Daniel, Messroghli
- Subjects
AMYLOIDOSIS diagnosis ,RADIONUCLIDE imaging ,CATHETER ablation - Abstract
We present not‐yet‐seen multimodal images of a 55‐year‐old female patient with isolated atrial amyloidosis (IAA) who clinically suffered from multiple atrial arrhythmias and heart failure symptoms with preserved left ventricular ejection fraction. We aim to show structural and functional abnormalities detected by electrophysiological voltage mapping, cardiac magnetic resonance imaging (MRI) [cMRI; atrial strain measurements, late gadolinium enhancement (LGE) visualization], and 99mTc‐DPD scintigraphy. Bipolar voltage mapping performed during two electrophysiological procedures showed diffuse left atrial low‐voltage areas (bipolar < 0.5 mV) and also a moderately diseased right atrium suspected of infiltrative cardiomyopathy. Catheter ablation did successfully treat a left atrial and two right atrial focal tachycardias. For further diagnostics, a 3T cMRI was performed, revealing a subendocardial circumferential left atrial LGE and pathological atrial strain measurements, especially during conduit and reservoir phase. Afterwards, nuclear imaging with 559 MBq of 99mTc‐DPD was performed. The scan revealed amyloid infiltration of the left atrium. Neither an uptake in the ventricular myocardium nor an extra‐cardiac uptake of DPD was seen. Genetic testing for transthyretin amyloidosis mutations in this patient was negative, and peripheral neuropathy was ruled out by electromyogram analysis. The synopsis of these findings reveals IAA as the most possible diagnosis and showed isolated atrial nuclear tracer uptake with 99mTc‐DPD scintigraphy for the first time. Non‐invasive imaging techniques might help in suggesting IAA but need further investigation. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
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