77 results on '"Hametner C"'
Search Results
2. Vom Schlaganfall zur Reperfusion: Wie geht es schneller?
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Härtig, F., Purrucker, J., Hametner, C., and Poli, S.
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- 2016
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3. Efficient real driving emissions calibration of automotive powertrains under operating uncertainties.
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Wasserburger, A., Didcock, N., and Hametner, C.
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DISTRIBUTION (Probability theory) ,CALIBRATION ,AUTOMOBILE power trains - Abstract
The steady-state calibration of automotive powertrains is typically based on the assumption of one specific drive cycle and perfectly controllable operating conditions. During real operation, however, these assumptions are violated, which implies that the calibration might in fact not be optimal. Therefore, in order to achieve reliable performance in a real-world setting, these uncertainties have to have been considered already during the calibration process. In this article, a stochastic optimization approach that takes the mentioned operating uncertainties into account by including probability distributions of the disturbances, is suggested. Furthermore, an approximation is derived of the distribution of the optimization performance criterion that greatly reduces the computational load during optimization compared with Monte Carlo sampling. Simulation results show that the proposed probabilistic approach leads to lower expected values of emissions and consumption when compared with deterministic optimization approaches ignoring the stochastic influences. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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4. Efficient real driving emissions calibration of automotive powertrains under operating uncertainties
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Wasserburger, A., primary, Didcock, N., additional, and Hametner, C., additional
- Published
- 2021
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5. EndoVAscular treatment and ThRombolysis for Ischemic Stroke Patients (EVA-TRISP) registry: Basis and methodology of a pan-European prospective ischaemic stroke revascularisation treatment registry
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Nordanstig, A. Curtze, S. Gensicke, H. Zinkstok, S.M. Erdur, H. Karlsson, C. Karlsson, J.-E. Martinez-Majander, N. Sibolt, G. Lyrer, P. Traenka, C. Baharoglu, M.I. Scheitz, J.F. Bricout, N. Hénon, H. Leys, D. Eskandari, A. Michel, P. Hametner, C. Ringleb, P.A. Arnold, M. Fischer, U. Sarikaya, H. Seiffge, D.J. Pezzini, A. Zini, A. Padjen, V. Jovanovic, D.R. Luft, A. Wegener, S. Kellert, L. Feil, K. Kägi, G. Rentzos, A. Lappalainen, K. Leker, R.R. Cohen, J.E. Gomori, J. Brehm, A. Liman, J. Psychogios, M. Kastrup, A. Papanagiotou, P. Gralla, J. Magoni, M. Majoie, C.B.L.M. Bohner, G. Vukasinovic, I. Cvetic, V. Weber, J. Kulcsar, Z. Bendszus, M. Möhlenbruch, M. Ntaios, G. Kapsalaki, E. Jood, K. Nolte, C.H. Nederkoorn, P.J.J. Engelter, S. Strbian, D. Tatlisumak, T.
- Abstract
Purpose The Thrombolysis in Ischemic Stroke Patients (TRISP) collaboration was a concerted effort initiated in 2010 with the purpose to address relevant research questions about the effectiveness and safety of intravenous thrombolysis (IVT). The collaboration also aims to prospectively collect data on patients undergoing endovascular treatment (EVT) and hence the name of the collaboration was changed from TRISP to EVA-TRISP. The methodology of the former TRISP registry for patients treated with IVT has already been published. This paper focuses on describing the EVT part of the registry. Participants All centres committed to collecting predefined variables on consecutive patients prospectively. We aim for accuracy and completeness of the data and to adapt local databases to investigate novel research questions. Herein, we introduce the methodology of a recently constructed academic investigator-initiated open collaboration EVT registry built as an extension of an existing IVT registry in patients with acute ischaemic stroke (AIS). Findings to date Currently, the EVA-TRISP network includes 20 stroke centres with considerable expertise in EVT and maintenance of high-quality hospital-based registries. Following several successful randomised controlled trials (RCTs), many important clinical questions remain unanswered in the (EVT) field and some of them will unlikely be investigated in future RCTs. Prospective registries with high-quality data on EVT-treated patients may help answering some of these unanswered issues, especially on safety and efficacy of EVT in specific patient subgroups. Future plans This collaborative effort aims at addressing clinically important questions on safety and efficacy of EVT in conditions not covered by RCTs. The TRISP registry generated substantial novel data supporting stroke physicians in their daily decision making considering IVT candidate patients. While providing observational data on EVT in daily clinical practice, our future findings may likewise be hypothesis generating for future research as well as for quality improvement (on EVT). The collaboration welcomes participation of further centres willing to fulfill the commitment and the outlined requirements. © 2021 BMJ Publishing Group. All rights reserved.
- Published
- 2021
6. Risk-averse real driving emissions optimization considering stochastic influences
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Wasserburger, A., primary, Hametner, C., additional, and Didcock, N., additional
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- 2019
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7. Online estimation of the electrochemical impedance of polymer electrolyte membrane fuel cells using broad-band current excitation
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Ritzberger, D., primary, Striednig, M., additional, Simon, C., additional, Hametner, C., additional, and Jakubek, S., additional
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- 2018
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8. Risk-averse real driving emissions optimization considering stochastic influences.
- Author
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Wasserburger, A., Hametner, C., and Didcock, N.
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RISK aversion , *PROCESS optimization , *ENERGY consumption - Abstract
Optimization of vehicle powertrains is usually based on specific drive cycles and is performed on testbeds under reproducible conditions. However, in real-world operation, energy consumption and emissions differ significantly from the values obtained in testbed environments, which also implies breaching legislative thresholds. Therefore, in order to close the gap between testbed and real world, it is necessary to take random effects, like varying road and ambient conditions or various traffic situations, into account during the engine calibration process. In this article a stochastic optimization approach based on risk measures, that quantify the prevalent uncertainties, is presented. Rather than optimizing a deterministic value for one specific scenario described by a drive cycle, the distribution of possible outcomes is shaped in a way that it reflects the risk aversion and preferences of the decision maker. Simulation results show that incorporating randomness in the optimization process yields substantially more robust and reliable results. [ABSTRACT FROM AUTHOR]
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- 2020
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9. Isolation and characterisation of enzymatic zearalenone hydrolysis reaction products
- Author
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Vekiru, E., primary, Fruhauf, S., additional, Hametner, C., additional, Schatzmayr, G., additional, Krska, R., additional, Moll, W.D., additional, and Schuhmacher, R., additional
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- 2016
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10. Vom Schlaganfall zur Reperfusion
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Härtig, F., primary, Purrucker, J., additional, Hametner, C., additional, and Poli, S., additional
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- 2015
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11. Characterisation and determination of metabolites formed by microbial and enzymatic degradation of ergot alkaloids
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Hahn, I., primary, Thamhesl, M., additional, Apfelthaler, E., additional, Klingenbrunner, V., additional, Hametner, C., additional, Krska, R., additional, Schatzmayr, G., additional, Moll, W.-D., additional, Berthiller, F., additional, and Schwartz-Zimmermann, H.E., additional
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- 2015
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12. Enhanced catalytic activity of carbonate buffer for isomerization of D-galactose into D-tagatose.
- Author
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Milasing N, Toussaint V, Hametner C, Khuwijitjaru P, and Delidovich I
- Abstract
D-tagatose (Tag) is a rare monosaccharide with health benefits. In this work, catalytic activity of CAPS (pH 10.4), carbonate (pH 10.4), triethylamine (pH 11.2), quinuclidine (pH 11.5), and L-arginine (pH 12.5) was examined for isomerization of D-galactose (Gal) to Tag. The maximum yields of Tag were 15.0 % with CAPS, 15.2 % with carbonate, 19.3 % with triethylamine, 19.6 % with quinuclidine, and 18.1 % with L-arginine. Despite identical pH, the Tag formation rate with carbonate buffer was 3-8 times higher than with CAPS. For carbonate buffer, the reaction orders for hydroxide and carbonate anions were ∼ 1 and ∼ 0, respectively. Operando NMR studies of Gal-1-
13 C isomerization in carbonate and CAPS buffers indicate similar tautomeric distributions of the substrate in both buffers. The deuterium kinetic isotope effect demonstrated that carbonate facilitates isomerization through a proton transfer mechanism, with hydroxide anions acting as the catalytically active species whereas carbonate anions stabilize the enediolate anion and/or the transition state., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2025 Elsevier Ltd. All rights reserved.)- Published
- 2025
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13. Endovascular Treatment of Stroke Due to Medium-Vessel Occlusion.
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Goyal M, Ospel JM, Ganesh A, Dowlatshahi D, Volders D, Möhlenbruch MA, Jumaa MA, Nimjee SM, Booth TC, Buck BH, Kennedy J, Shankar JJ, Dorn F, Zhang L, Hametner C, Nardai S, Zafar A, Diprose W, Vatanpour S, Stebner A, Bosshart S, Singh N, Sebastian I, Uchida K, Ryckborst KJ, Fahed R, Hu SX, Vollherbst DF, Zaidi SF, Lee VH, Lynch J, Rempel JL, Teal R, Trivedi A, Bode FJ, Ogungbemi A, Pham M, Orosz P, Abdalkader M, Taschner C, Tarpley J, Poli S, Singh RJ, De Leacy R, Lopez G, Sahlas D, Chen M, Burns P, Schaafsma JD, Marigold R, Reich A, Amole A, Field TS, Swartz RH, Settecase F, Lenzsér G, Ortega-Gutierrez S, Asdaghi N, Lobotesis K, Siddiqui AH, Berrouschot J, Mokin M, Ebersole K, Schneider H, Yoo AJ, Mandzia J, Klostranec J, Jadun C, Patankar T, Sauvageau E, Lenthall R, Peeling L, Huynh T, Budzik R, Lee SK, Makalanda L, Levitt MR, Perry RJ, Hlaing T, Jahromi BS, Singh P, Demchuk AM, and Hill MD
- Abstract
Background: Whether the large effect size of endovascular thrombectomy (EVT) for stroke due to large-vessel occlusion applies to stroke due to medium-vessel occlusion is unclear., Methods: In a multicenter, prospective, randomized, open-label trial with blinded outcome evaluation, we assigned patients with acute ischemic stroke due to medium-vessel occlusion who presented within 12 hours from the time that they were last known to be well and who had favorable baseline noninvasive brain imaging to receive EVT plus usual care or usual care alone. The primary outcome was the modified Rankin scale score (range, 0 [no symptoms] to 6 [death]) at 90 days, reported as the percentage of patients with a score of 0 or 1., Results: A total of 530 patients from five countries were enrolled between April 2022 and June 2024, with 255 patients assigned to the EVT group and 275 to the usual-care group. Most patients (84.7%) had primary occlusions in a middle-cerebral-artery branch. A modified Rankin scale score of 0 or 1 at 90 days occurred in 106 of 255 patients (41.6%) in the EVT group and in 118 of 274 (43.1%) in the usual-care group (adjusted rate ratio, 0.95; 95% confidence interval [CI], 0.79 to 1.15; P = 0.61). Mortality at 90 days was 13.3% in the EVT group and 8.4% in the usual-care group (adjusted hazard ratio, 1.82; 95% CI, 1.06 to 3.12). Symptomatic intracranial hemorrhage occurred in 14 of 257 patients (5.4%) in the EVT group and in 6 of 272 (2.2%) in the usual-care group., Conclusions: Endovascular treatment for acute ischemic stroke due to medium-vessel occlusion within 12 hours did not lead to better outcomes at 90 days than usual care. (Funded by the Canadian Institutes for Health Research and Medtronic; ESCAPE-MeVO ClinicalTrials.gov number, NCT05151172.)., (Copyright © 2025 Massachusetts Medical Society.)
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- 2025
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14. Prognostic serum biomarkers of synaptic, neuronal and glial injury in patients with acute ischemic stroke of the anterior circulation.
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Barba L, Vollmuth C, Halbgebauer S, Ungethüm K, Hametner C, Essig F, Kollikowski AM, Pham M, Schuhmann MK, Heuschmann PU, Oeckl P, Steinacker P, Romoli M, D'Anna L, Abu-Rumeileh S, Haeusler KG, Stoll G, Neugebauer H, and Otto M
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- Humans, Male, Female, Aged, Prognosis, Aged, 80 and over, Neurofilament Proteins blood, Middle Aged, Neuroglia, Neurons pathology, Synapses, Biomarkers blood, Ischemic Stroke blood, Ischemic Stroke mortality, Glial Fibrillary Acidic Protein blood
- Abstract
Background: We aimed to investigate the prognostic role of β-synuclein in comparison to that of neurofilament light chain (NfL) and glial fibrillary acidic protein (GFAP) for predicting functional outcome after acute ischemic stroke (AIS)., Methods: We measured serum concentrations of β-synuclein, NfL and GFAP 24 h after hospital admission in 213 consecutive patients with moderate-to-severe AIS. We investigated the association between serum biomarkers and radiological/clinical characteristics, 3-months mortality and functional outcome on the modified Rankin Scale (mRS)., Results: In 213 patients with AIS [mean age: 76.1 (±12.5) years, 53.1% males, median NIHSS score on admission: 13 (IQR: 9-17)], higher levels of β-synuclein, NfL and GFAP were associated with higher NIHSS scores and with lower Alberta Stroke Program CT Score (ASPECTS) points on admission. Serum β-synuclein levels was significantly correlated with NfL (rho = 0.715, p < 0.001) and GFAP concentrations (rho = 0.684, p < 0.001). The inclusion of serum β-synuclein significantly improved the accuracy of prediction models without biomarkers for overall mortality (AUC: 0.836 vs. 0.752, p < 0.001) and mRS 3-6 vs. 0-2 (AUC: 0.812 vs. 0.624, p < 0.001). Combination models with NfL and/or GFAP showed a similar accuracy., Conclusions: Serum β-synuclein may be used to assess synaptic damage/dysfunction and to predict 3-months clinical outcomes in patients with AIS., (© 2024 The Author(s). European Journal of Neurology published by John Wiley & Sons Ltd on behalf of European Academy of Neurology.)
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- 2025
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15. A two-step identification approach for an extended nonlinear double-capacitor model.
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Genario de Oliveira J Jr, Aras C, Pallewar P, Charkhgard M, Sivaraman T, and Hametner C
- Abstract
Equivalent circuits are one of the most used models for Li-ion cells in the automotive area. However, it is a challenge to these models to be able to capture the cell discharge capacity under different loads, while still being accurate on both continuous charge and dynamic tests, fast to compute, and easy to parametrize from non-specialized data. To tackle this challenge, this paper proposes an extension of the nonlinear double capacitor model by increasing its order, parameter dependency with C-rate, and an identification procedure that exploits the pseudo-linear nature of the problem to find the parameter maps. An analogy between the parts of the circuit and the single particle model is also presented to reduce the search space of the identification algorithm and to enhance model interpretability. The performance of the proposed model extension is analyzed and compared to a state-of-the-art model on a challenging LiFePO4 dataset with different characteristics and validated on a realistic drive cycle, obtaining a mean absolute average error of around 20 mV for both training and validation tests., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024 The Authors.)
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- 2024
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16. MMP-9 release into collateral blood vessels before endovascular thrombectomy to assess the risk of major intracerebral haemorrhages and poor outcome for acute ischaemic stroke: a proof-of-concept study.
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Kollikowski AM, Pham M, März AG, Feick J, Vogt ML, Xiong Y, Strinitz M, Vollmuth C, Essig F, Neugebauer H, Haeusler KG, Hametner C, Zimmermann L, Stoll G, and Schuhmann MK
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- Humans, Male, Female, Aged, Middle Aged, Prognosis, Aged, 80 and over, Matrix Metalloproteinase 2 metabolism, Matrix Metalloproteinase 2 blood, Biomarkers, Treatment Outcome, Cross-Sectional Studies, ROC Curve, Collateral Circulation, Matrix Metalloproteinase 9 metabolism, Matrix Metalloproteinase 9 blood, Thrombectomy methods, Cerebral Hemorrhage etiology, Cerebral Hemorrhage metabolism, Ischemic Stroke metabolism, Ischemic Stroke etiology, Ischemic Stroke diagnosis, Ischemic Stroke therapy, Endovascular Procedures methods
- Abstract
Background: Matrix metalloproteinases (MMPs) are implied in blood-brain barrier degradation and haemorrhagic transformation following ischaemic stroke, but their local relevance in the hyperacute disease phase is unknown. We aimed to examine ultra-early MMP-9 and MMP-2 release into collateral blood vessels, and to assess its prognostic value before therapeutic recanalisation by endovascular thrombectomy (EVT)., Methods: We report a cross-sectional proof-of-concept study including patients undergoing EVT for large-vessel ischaemic stroke at the University Hospital Würzburg, Germany. We obtained liquid biopsies from the collateral circulation before recanalisation, and systemic control samples. Laboratory workup included quantification of MMP-9 and MMP-2 plasma concentrations by cytometric bead array, immunohistochemical analyses of cellular MMP-9 and MMP-2 expression, and detection of proteolytic activity by gelatine zymography. The clinical impact of MMP concentrations was assessed by stratification according to intracranial haemorrhagic lesions on postinterventional computed tomography (Heidelberg Bleeding Classification, HBC) and early functional outcome (modified Rankin Scale, mRS). We used multivariable logistic regression, receiver-operating-characteristic (ROC) curves, and fixed-level estimates of test accuracy measures to study the prognostic value of MMP-9 concentrations., Findings: Between August 3, 2018, and September 16, 2021, 264 matched samples from 132 patients (86 [65.2%] women, 46 [34.8%] men, aged 40-94 years) were obtained. Median (interquartile range, IQR) MMP-9 (279.7 [IQR 126.4-569.6] vs 441 [IQR 223.4-731.5] ng/ml, p < 0.0001) but not MMP-2 concentrations were increased within collateral blood vessels. The median MMP-9 expression level of invading neutrophils was elevated (fluorescence intensity, arbitrary unit: 2276 [IQR 1007-5086] vs 3078 [IQR 1108-7963], p = 0.0018). Gelatine zymography experiments indicated the locally confined proteolytic activity of MMP-9 but not of MMP-2. Pretherapeutic MMP-9 release into stroke-affected brain regions predicted the degree of intracerebral haemorrhages and clinical stroke severity after recanalisation, and independently increased the odds of space-occupying parenchymal haematomas (HBC1c-3a) by 1.54 times, and the odds of severe disability or death (mRS ≥5 at hospital discharge) by 2.33 times per 1000 ng/ml increase. Excessive concentrations of MMP-9 indicated impending parenchymal haematomas and severe disability or death with high specificity., Interpretation: Measurement of MMP-9 within collateral blood vessels is feasible and identifies patients with stroke at risk of major intracerebral haemorrhages and poor outcome before therapeutic recanalisation by EVT, thereby providing evidence of the concept validity of ultra-early local stroke biomarkers., Funding: This work was funded by the German Research Foundation (Deutsche Forschungsgemeinschaft, DFG) and the Interdisciplinary Centre for Clinical Research (IZKF) at the University of Würzburg., Competing Interests: Declaration of interests MP has received speaker honoraria from Bayer and Merck Serono; unrelated to the present study. KGH has received honoraria for acting as an advisor/speaker for Boehringer Ingelheim; unrelated to the present study. MKS declares a grant from CSL Behring, funding from the German Research Foundation (Deutsche Forschungsgemeinschaft, DFG) project No. 424778381—CRC/TR 295, and is a co-holder of patent PCT/EP2020/068464; all unrelated to the present study. All other authors have nothing to disclose., (Copyright © 2024 The Author(s). Published by Elsevier B.V. All rights reserved.)
- Published
- 2024
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17. An Atraumatic Mock Loop for Realistic Hemocompatibility Assessment of Blood Pumps.
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Bender M, Escher A, Messner B, Rohrich M, Fischer MB, Hametner C, Laufer G, Kertzscher U, Zimpfer D, Jakubek S, and Granegger M
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- Animals, Cattle, Equipment Design, Hemodynamics physiology, Materials Testing methods, Models, Cardiovascular, Humans, Heart-Assist Devices, Hemolysis physiology
- Abstract
Objective: Conventional mock circulatory loops (MCLs) cannot replicate realistic hemodynamic conditions without inducing blood trauma. This constrains in-vitro hemocompatibility examinations of blood pumps to static test loops that do not mimic clinical scenarios. This study aimed at developing an atraumatic MCL based on a hardware-in-the-loop concept (H-MCL) for realistic hemocompatibility assessment., Methods: The H-MCL was designed for 450 ± 50 ml of blood with the polycarbonate reservoirs, the silicone/polyvinyl-chloride tubing, and the blood pump under investigation as the sole blood-contacting components. To account for inherent coupling effects a decoupling pressure control was derived by feedback linearization, whereas the level control was addressed by an optimization task to overcome periodic loss of controllability. The HeartMate 3 was showcased to evaluate the H-MCL's accuracy at typical hemodynamic conditions. To verify the atraumatic properties of the H-MCL, hemolysis (bovine blood, n = 6) was evaluated using the H-MCL in both inactive (static) and active (minor pulsatility) mode, and compared to results achieved in conventional loops., Results: Typical hemodynamic scenarios were replicated with marginal coupling effects and root mean square error (RMSE) below 1.74 ± 1.37 mmHg while the fluid level remained within ±4% of its target value. The normalized indices of hemolysis (NIH) for the inactive H-MCL showed no significant differences to conventional loops ( ∆NIH = -1.6 mg/100 L). Further, no significant difference was evident between the active and inactive mode in the H-MCL ( ∆NIH = +0.3 mg/100 L)., Conclusion and Significance: Collectively, these findings indicated the H-MCL's potential for in-vitro hemocompatibility assessment of blood pumps within realistic hemodynamic conditions, eliminating inherent setup-related risks for blood trauma.
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- 2024
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18. Safety and effectiveness of IV Thrombolysis in retinal artery occlusion: A multicenter retrospective cohort study.
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Baumgartner P, Kook L, Altersberger VL, Gensicke H, Ardila-Jurado E, Kägi G, Salerno A, Michel P, Gopisingh KM, Nederkoorn PJ, Scheitz JF, Nolte CH, Heldner MR, Arnold M, Cordonnier C, Della Schiava L, Hametner C, Ringleb PA, Leker RR, Jubran H, Luft AR, Engelter ST, and Wegener S
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- Humans, Retrospective Studies, Thrombolytic Therapy adverse effects, Treatment Outcome, Intracranial Hemorrhages etiology, Stroke drug therapy, Retinal Artery Occlusion drug therapy
- Abstract
Background: Retinal artery occlusion (RAO) may lead to irreversible blindness. For acute RAO, intravenous thrombolysis (IVT) can be considered as treatment. However, due to the rarity of RAO, data about IVT safety and effectiveness is limited., Methods: From the multicenter database ThRombolysis for Ischemic Stroke Patients (TRISP), we retrospectively analyzed visual acuity (VA) at baseline and within 3 months in IVT and non-IVT treated RAO patients. Primary outcome was difference of VA between baseline and follow up (∆VA). Secondary outcomes were rates of visual recovery (defined as improvement of VA ⩾ 0.3 logMAR), and safety (symptomatic intracranial hemorrhage (sICH) according to ECASS II criteria, asymptomatic intracranial hemorrhage (ICH) and major extracranial bleeding). Statistical analysis was performed using parametric tests and a linear regression model adjusted for age, sex and baseline VA., Results: We screened 200 patients with acute RAO and included 47 IVT and 34 non-IVT patients with complete information about recovery of vision. Visual Acuity at follow up significantly improved compared to baseline in IVT patients (∆VA 0.5 ± 0.8, p < 0.001) and non-IVT patients (∆VA 0.40 ± 1.1, p < 0.05). No significant differences in ∆VA and visual recovery rate were found between groups at follow up. Two asymptomatic ICH (4%) and one (2%) major extracranial bleeding (intraocular bleeding) occurred in the IVT group, while no bleeding events were reported in the non-IVT group., Conclusion: Our study provides real-life data from the largest cohort of IVT treated RAO patients published so far. While there is no evidence for superiority of IVT compared to conservative treatment, bleeding rates were low. A randomized controlled trial and standardized outcome assessments in RAO patients are justified to assess the net benefit of IVT in RAO., Competing Interests: Declaration of conflicting interestsThe author(s) declared the following potential conflicts of interest with respect to the research, authorship, and/or publication of this article: PB: Research funds by the Gottfried and Julia Bangerter-Rhyner Foundation and Swiss Academy of Medical Sciences and funding for travel and conference fees from BMS/Pfizer. SW: Research funds by the Swiss National Science Foundation, the UZH Clinical research priority program (CRPP) stroke, the Swiss Heart foundation, the Zurich Neuroscience Center (ZNZ), speaker honoraria from Springer, Teva Pharma and consultancy fees from Bayer and Novartis. STE has received funding for travel or speaker honoraria from Bayer, Boehringer Ingelheim and Daiichi-Sankyo. He has served on scientific advisory boards for Bayer, Boehringer Ingelheim, BMS/Pfizer, and MindMaze and on the editorial board of Stroke. His institutions have received an educational grant from Pfizer, compensation from Stago for educational efforts and research support from Daiichi-Sankyo, the Science Funds [Wissenschaftsfonds] of the University Hospital Basel, the University Basel, from the “Wissenschaftsfonds Rehabilitation” of the University Department for Geriatric Medicine Felix Platter, the “Freiwillige Akademische Gesellschaft Basel,” the Swiss Heart Foundation, and the Swiss National Science Foundation. PR has received honoraria for advisory board participation from Boehringer Ingelheim and Pfizer and lecture fees from Boehringer Ingelheim, Bayer, Pfizer and Daiichi Sankyo. His institution has received a grant from Boehringer Ingelheim for the ECASS-4 Study. RRL received funding for speaker honoraria from Pfizer, Boehringer Ingelheim, Biogen and Iscehma View. He has served on scientific advisory boards for Novo-Nordisk and Bayer.
- Published
- 2023
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19. IV Thrombolysis With or Without Endovascular Treatment for Suspected Ischemic Stroke in Patients With Intracranial Tumors.
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Seystahl K, Martinez-Majander N, Salerno A, Beyeler M, Erdur H, Marto JP, Hametner C, Zedde M, Pezzini A, Leker R, Altersberger V, Costamagna G, Serôdio M, Migliaccio L, Pascarella R, Zini A, Mannismäki L, Béjot Y, Jung S, Gensicke H, Padjen V, Ringleb PA, Nolte C, Heldner MR, Michel P, Engelter ST, Curtze S, Weller M, and Wegener S
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- Humans, Fibrinolytic Agents therapeutic use, Thrombolytic Therapy adverse effects, Prospective Studies, Intracranial Hemorrhages etiology, Intracranial Hemorrhages chemically induced, Treatment Outcome, Ischemic Stroke drug therapy, Brain Ischemia diagnostic imaging, Brain Ischemia drug therapy, Brain Ischemia complications, Pituitary Neoplasms complications, Stroke diagnostic imaging, Stroke drug therapy, Stroke complications
- Abstract
Background and Objectives: IV thrombolysis (IVT) for suspected ischemic stroke in patients with intracranial neoplasms is off-label. However, data on risks of intracranial hemorrhage (ICH) are scarce., Methods: In a multicenter registry-based analysis within the European Thrombolysis in Ischemic Stroke Patients (TRISP) collaboration, we assessed frequencies of symptomatic and fatal ICH after IVT for suspected ischemic stroke in patients with intracranial tumors by descriptive statistics and analyzed associations with clinical and imaging characteristics by binary logistic regression. Definition of symptomatic ICH was based on the clinical criteria of the European Cooperative Acute Stroke-II trial including hemorrhage at any site in cranial imaging and concurrent clinical deterioration., Results: Screening data of 21,289 patients from 14 centers, we identified 105 patients receiving IVT; among them were 29 patients (28%) with additional endovascular treatment, with suspected, that is, imaging-based, or histologically confirmed diagnosis of intracranial tumors. Among 104 patients with CT or MRI after IVT available, symptomatic and fatal ICH were observed in 9 and 4 patients (9% and 4%, respectively). Among 82 patients with suspected or confirmed meningioma, symptomatic and fatal ICH occurred in 6 and 3 patients (7% and 4%), respectively. In 18 patients with intra-axial suspected or confirmed primary or secondary brain tumors, there was 1 symptomatic nonfatal ICH (6%). Of 4 patients with tumors of the pituitary region, 2 patients (50%) had symptomatic ICH including 1 fatal ICH (25%). Tumor size was not associated with the occurrence of symptomatic ICH (odds ratio 2.8, 95% CI 0.3-24.8, p = 0.34)., Discussion: In our dataset from routine clinical care, we provide insights on the safety of IVT for suspected ischemic stroke in patients with intracranial tumors, a population that is commonly withheld thrombolysis in clinical practice and prospective trials. Except for a potential high risk of symptomatic ICH after IVT in patients with tumors of the pituitary region, frequencies of symptomatic ICH in patients with intracranial tumors in our cohort seem to be in the upper range of rates observed in previous studies within the TRISP cooperation. These results may guide individual treatment decisions in patients with acute stroke and intracranial tumors with potential benefit of IVT., (© 2023 American Academy of Neurology.)
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- 2023
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20. Intravenous Thrombolysis 4.5-9 Hours After Stroke Onset: A Cohort Study from the TRISP Collaboration.
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Altersberger VL, Sibolt G, Enz LS, Hametner C, Scheitz JF, Henon H, Bigliardi G, Strambo D, Martinez-Majander N, Stolze LJ, Heldner MR, Grisendi I, Jovanovic DR, Bejot Y, Pezzini A, Leker RR, Kägi G, Wegener S, Cereda CW, Ntaios G, De Marchis GM, Bonati LH, Psychogios M, Lyrer P, Räty S, Tiainen M, Wouters A, Caparros F, Heyse M, Erdur H, Padjen V, Zedde M, Arnold M, Nederkoorn PJ, Michel P, Zini A, Cordonnier C, Nolte CH, Ringleb PA, Curtze S, Engelter ST, and Gensicke H
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- Humans, Cohort Studies, Prospective Studies, Thrombolytic Therapy methods, Intracranial Hemorrhages etiology, Treatment Outcome, Fibrinolytic Agents therapeutic use, Stroke diagnostic imaging, Stroke drug therapy, Ischemic Stroke complications, Brain Ischemia diagnostic imaging, Brain Ischemia drug therapy, Brain Ischemia complications
- Abstract
Objective: To investigate the safety and effectiveness of intravenous thrombolysis (IVT) >4.5-9 hours after stroke onset, and the relevance of advanced neuroimaging for patient selection., Methods: Prospective multicenter cohort study from the ThRombolysis in Ischemic Stroke Patients (TRISP) collaboration. Outcomes were symptomatic intracranial hemorrhage, poor 3-month functional outcome (modified Rankin scale 3-6) and mortality. We compared: (i) IVT >4.5-9 hours versus 0-4.5 hours after stroke onset and (ii) within the >4.5-9 hours group baseline advanced neuroimaging (computed tomography perfusion, magnetic resonance perfusion or magnetic resonance diffusion-weighted imaging fluid-attenuated inversion recovery) versus non-advanced neuroimaging., Results: Of 15,827 patients, 663 (4.2%) received IVT >4.5-9 hours and 15,164 (95.8%) within 4.5 hours after stroke onset. The main baseline characteristics were evenly distributed between both groups. Time of stroke onset was known in 74.9% of patients treated between >4.5 and 9 hours. Using propensity score weighted binary logistic regression analysis (onset-to-treatment time >4.5-9 hours vs onset-to-treatment time 0-4.5 hours), the probability of symptomatic intracranial hemorrhage (OR
adjusted 0.80, 95% CI 0.53-1.17), poor functional outcome (ORadjusted 1.01, 95% CI 0.83-1.22), and mortality (ORadjusted 0.80, 95% CI 0.61-1.04) did not differ significantly between both groups. In patients treated between >4.5 and 9 hours, the use of advanced neuroimaging was associated with a 50% lower mortality compared with non-advanced imaging only (9.9% vs 19.7%; ORadjusted 0.51, 95% CI 0.33-0.79)., Interpretation: This study showed no evidence in difference of symptomatic intracranial hemorrhage, poor outcome, and mortality in selected stroke patients treated with IVT between >4.5 and 9 hours after stroke onset compared with those treated within 4.5 hours. Advanced neuroimaging for patient selection was associated with lower mortality. ANN NEUROL 2023;94:309-320., (© 2023 The Authors. Annals of Neurology published by Wiley Periodicals LLC on behalf of American Neurological Association.)- Published
- 2023
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21. Recanalization Therapies for Large Vessel Occlusion Due to Cervical Artery Dissection: A Cohort Study of the EVA-TRISP Collaboration.
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Traenka C, Lorscheider J, Hametner C, Baumgartner P, Gralla J, Magoni M, Martinez-Majander N, Casolla B, Feil K, Pascarella R, Papanagiotou P, Nordanstig A, Padjen V, Cereda CW, Psychogios M, Nolte CH, Zini A, Michel P, Béjot Y, Kastrup A, Zedde M, Kägi G, Kellert L, Henon H, Curtze S, Pezzini A, Arnold M, Wegener S, Ringleb P, Tatlisumak T, Nederkoorn PJ, Engelter ST, and Gensicke H
- Abstract
Background and Purpose: This study aimed to investigate the effect of endovascular treatment (EVT, with or without intravenous thrombolysis [IVT]) versus IVT alone on outcomes in patients with acute ischemic stroke (AIS) and intracranial large vessel occlusion (LVO) attributable to cervical artery dissection (CeAD)., Methods: This multinational cohort study was conducted based on prospectively collected data from the EVA-TRISP (EndoVAscular treatment and ThRombolysis for Ischemic Stroke Patients) collaboration. Consecutive patients (2015-2019) with AIS-LVO attributable to CeAD treated with EVT and/or IVT were included. Primary outcome measures were (1) favorable 3-month outcome (modified Rankin Scale score 0-2) and (2) complete recanalization (thrombolysis in cerebral infarction scale 2b/3). Odds ratios with 95% confidence intervals (OR [95% CI]) from logistic regression models were calculated (unadjusted, adjusted). Secondary analyses were performed in the patients with LVO in the anterior circulation (LVOant) including propensity score matching., Results: Among 290 patients, 222 (76.6%) had EVT and 68 (23.4%) IVT alone. EVT-treated patients had more severe strokes (National Institutes of Health Stroke Scale score, median [interquartile range]: 14 [10-19] vs. 4 [2-7], P<0.001). The frequency of favorable 3-month outcome did not differ significantly between both groups (EVT: 64.0% vs. IVT: 86.8%; ORadjusted 0.56 [0.24-1.32]). EVT was associated with higher rates of recanalization (80.5% vs. 40.7%; ORadjusted 8.85 [4.28-18.29]) compared to IVT. All secondary analyses showed higher recanalization rates in the EVT-group, which however never translated into better functional outcome rates compared to the IVT-group., Conclusion: We observed no signal of superiority of EVT over IVT regarding functional outcome in CeAD-patients with AIS and LVO despite higher rates of complete recanalization with EVT. Whether pathophysiological CeAD-characteristics or their younger age might explain this observation deserves further research.
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- 2023
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22. Intravenous Thrombolysis in Patients With Ischemic Stroke Aged ≥90 Years: A Cohort Study From the TRISP Collaboration.
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Altersberger VL, Rusche N, Martinez-Majander N, Hametner C, Scheitz JF, Henon H, Dell'Acqua ML, Strambo D, Stolp J, Heldner MR, Grisendi I, Jovanovic DR, Bejot Y, Pezzini A, Leker RR, Kägi G, Wegener S, Cereda CW, Lindgren E, Ntaios G, Piot I, Polymeris AA, Lyrer PA, Räty S, Sibolt G, Tiainen M, Heyse M, Erdur H, Kaaouana O, Padjen V, Zedde M, Arnold M, Nederkoorn PJ, Michel P, Bigliardi G, Zini A, Cordonnier C, Nolte CH, Ringleb PA, Curtze S, Engelter ST, and Gensicke H
- Subjects
- Aged, 80 and over, Aged, Humans, Thrombolytic Therapy methods, Cohort Studies, Prospective Studies, Treatment Outcome, Intracranial Hemorrhages chemically induced, Intracranial Hemorrhages epidemiology, Intracranial Hemorrhages drug therapy, Fibrinolytic Agents adverse effects, Brain Ischemia drug therapy, Ischemic Stroke, Stroke drug therapy
- Abstract
Background: The probability to receive intravenous thrombolysis (IVT) for treatment of acute ischemic stroke declines with increasing age and is consequently the lowest in very elderly patients. Safety concerns likely influence individual IVT treatment decisions. Using data from a large IVT registry, we aimed to provide more evidence on safety of IVT in the very elderly., Methods: In this prospective multicenter study from the TRISP (Thrombolysis in Ischemic Stroke Patients) registry, we compared patients ≥90 years with those <90 years using symptomatic intracranial hemorrhage (ECASS [European Cooperative Acute Stroke Study]-II criteria), death, and poor functional outcome in survivors (modified Rankin Scale score 3-5 for patients with prestroke modified Rankin Scale score ≤2 and modified Rankin Scale score 4-5 for patients prestroke modified Rankin Scale ≥3) at 3 months as outcomes. We calculated adjusted odds ratio with 95% CI using logistic regression models., Results: Of 16 974 eligible patients, 976 (5.7%) were ≥90 years. Patients ≥90 years had higher median National Institutes of Health Stroke Scale on admission (12 versus 8) and were more often dependent prior to the index stroke (prestroke modified Rankin Scale score of ≥3; 45.2% versus 7.4%). Occurrence of symptomatic intracranial hemorrhage (5.7% versus 4.4%, odds ratio
adjusted 1.14 [0.83-1.57]) did not differ significantly between both groups. However, the probability of death (odds ratioadjusted 3.77 [3.14-4.53]) and poor functional outcome (odds ratioadjusted 2.63 [2.13-3.25]) was higher in patients aged ≥90 years. Results for the sample of centenarians (n=21) were similar., Conclusions: The probability of symptomatic intracranial hemorrhage after IVT in very elderly patients with stroke did not exceed that of their younger counterparts. The higher probability of death and poor functional outcome during follow-up in the very elderly seems not to be related to IVT treatment. Very high age itself should not be a reason to withhold IVT.- Published
- 2022
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23. Thrombolysis in stroke patients with elevated inflammatory markers.
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Altersberger VL, Enz LS, Sibolt G, Hametner C, Nannoni S, Heldner MR, Stolp J, Jovanovic DR, Zini A, Pezzini A, Wegener S, Cereda CW, Ntaios G, Räty S, Gumbinger C, Heyse M, Polymeris AA, Zietz A, Schaufelbuehl A, Strambo D, Padlina G, Slavova N, Tiainen M, Valkonen K, Velzen TJV, Bigliardi G, Stanarcevic P, Magoni M, Luft A, Bejot Y, Vandelli L, Padjen V, Nederkoorn PJ, Arnold M, Michel P, Ringleb PA, Curtze S, Engelter ST, and Gensicke H
- Subjects
- Fibrinolytic Agents adverse effects, Humans, Leukocytosis, Prospective Studies, Thrombolytic Therapy adverse effects, Treatment Outcome, Brain Ischemia complications, Leukopenia complications, Stroke complications, Stroke drug therapy, Stroke epidemiology, Thrombocytopenia
- Abstract
Objective: To investigate the prognostic value of white blood cell count (WBC) on functional outcome, mortality and bleeding risk in stroke patients treated with intravenous thrombolysis (IVT)., Methods: In this prospective multicenter study from the TRISP registry, we assessed the association between WBC on admission and 3-month poor outcome (modified Rankin Scale 3-6), mortality and occurrence of symptomatic intracranial hemorrhage (sICH; ECASS-II-criteria) in IVT-treated stroke patients. WBC was used as continuous and categorical variable distinguishing leukocytosis (WBC > 10 × 10
9 /l) and leukopenia (WBC < 4 × 109 /l). We calculated unadjusted/ adjusted odds ratios with 95% confidence intervals (OR [95% CI]) with logistic regression models. In a subgroup, we analyzed the association of combined leukocytosis and elevated C-reactive protein (CRP > 10 mg/l) on outcomes., Results: Of 10,813 IVT-treated patients, 2527 had leukocytosis, 112 leukopenia and 8174 normal WBC. Increasing WBC (by 1 × 109 /l) predicted poor outcome (ORadjusted 1.04[1.02-1.06]) but not mortality and sICH. Leukocytosis was independently associated with poor outcome (ORadjusted 1.48[1.29-1.69]) and mortality (ORadjusted 1.60[1.35-1.89]) but not with sICH (ORadjusted 1.17[0.94-1.45]). Leukopenia did not predict any outcome. In a subgroup, combined leukocytosis and elevated CRP had the strongest association with poor outcome (ORadjusted 2.26[1.76-2.91]) and mortality (ORadjusted 2.43[1.86-3.16]) when compared to combined normal WBC and CRP., Conclusion: In IVT-treated patients, leukocytosis independently predicted poor functional outcome and death. Bleeding complications after IVT were not independently associated with leukocytosis., (© 2022. The Author(s).)- Published
- 2022
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24. Beyond the Threshold: A Study of Chalcogenophene-Based Two-Photon Initiators.
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Lunzer M, Beckwith JS, Chalupa-Gantner F, Rosspeintner A, Licari G, Steiger W, Hametner C, Liska R, Fröhlich J, Vauthey E, Ovsianikov A, and Holzer B
- Abstract
A series of nine soluble, symmetric chalcogenophenes bearing hexyl-substituted triphenylamines, indolocarbazoles, or phenylcarbazoles was designed and synthesized as potential two-photon absorption (2PA) initiators. A detailed photophysical analysis of these molecules revealed good 2PA properties of the series and, in particular, a strong influence of selenium on the 2PA cross sections, rendering these materials especially promising new 2PA photoinitiators. Structuring and threshold tests proved the efficiency and broad spectral versatility of two selenium-containing lead compounds as well as their applicability in an acrylate resin formulation. A comparison with commercial photoinitiators Irg369 and BAPO as well as sensitizer ITX showed that the newly designed selenium-based materials TPA-S and TPA-BBS outperform these traditional initiators by far both in terms of reactivity and dose. Moreover, by increasing the ultralow concentration of TPA-BBS , a further reduction of the polymerization threshold can be achieved, revealing the great potential of this series for application in two-photon polymerization (2PP) systems where only low laser power is available., Competing Interests: The authors declare no competing financial interest., (© 2022 The Authors. Published by American Chemical Society.)
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- 2022
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25. Intensive care unit occupancy predictions in the COVID-19 pandemic based on age-structured modelling and differential flatness.
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Hametner C, Böhler L, Kozek M, Bartlechner J, Ecker O, Du ZP, Kölbl R, Bergmann M, Bachleitner-Hofmann T, and Jakubek S
- Abstract
The COVID-19 pandemic confronts governments and their health systems with great challenges for disease management. In many countries, hospitalization and in particular ICU occupancy is the primary measure for policy makers to decide on possible non-pharmaceutical interventions. In this paper a combined methodology for the prediction of COVID-19 case numbers, case-specific hospitalization and ICU admission rates as well as hospital and ICU occupancies is proposed. To this end, we employ differential flatness to provide estimates of the states of an epidemiological compartmental model and estimates of the unknown exogenous inputs driving its nonlinear dynamics. A main advantage of this method is that it requires the reported infection cases as the only data source. As vaccination rates and case-specific ICU rates are both strongly age-dependent, specifically an age-structured compartmental model is proposed to estimate and predict the spread of the epidemic across different age groups. By utilizing these predictions, case-specific hospitalization and case-specific ICU rates are subsequently estimated using deconvolution techniques. In an analysis of various countries we demonstrate how the methodology is able to produce real-time state estimates and hospital/ICU occupancy predictions for several weeks thus providing a sound basis for policy makers., Competing Interests: Conflict of interestThe authors declare that they have no conflict of interest., (© The Author(s) 2022.)
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- 2022
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26. Differential effects of the SARS-CoV-2 pandemic on patients presenting to a neurological emergency room depending on their triage score in an area with low COVID-19 incidence.
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Millán M, Nagel S, Gumbinger C, Busetto L, Purrucker JC, Hametner C, Ringleb PA, and Mundiyanapurath S
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- Communicable Disease Control, Emergency Service, Hospital, Humans, Incidence, Pandemics, Retrospective Studies, Triage, COVID-19, SARS-CoV-2
- Abstract
Background: We analyzed the effects of the SARS-CoV-2 pandemic on neurologic emergencies, depending on the patients' triage score in a setting with relatively few COVID-19 cases and without lack of resources., Methods: Consecutive patients of a tertiary care center with a dedicated neurologic emergency room (nER) were analyzed. The time period of the first lockdown in Germany (calendar weeks 12-17, 2020) was retrospectively compared to the corresponding period in 2019 regarding the number of patients presenting to the nER, the number of patients with specific triage scores (Heidelberg Neurological Triage Score), the number of patients with stroke, and the quality of stroke care., Results: A total of 4330 patients were included. Fewer patients presented themselves in 2020 compared to 2019 (median [interquartile range] per week: 134 [118-143] vs. 187 [182-192]; p = 0.015). The median numbers of patients per week with triage 1 (emergent) and 4 (non-urgent) were comparable (51 [43-58] vs. 59 [54-62]; p = 0.132, and 10 [4-16] vs. 16 [7-18]; p = 0.310, respectively).The median number of patients per week declined in categories 2 and 3 in 2020 (41 [37-45] vs. 57 [52-61]; p = 0.004, and 28 [23-35] vs. 61 [52-63]; p = 0.002, respectively. No change was observed in the absolute number of strokes (138 in 2019 and 141 in 2020). Quality metrics of stroke revascularization therapies (symptom-to-door time, door-to-needle time or relative number of therapies) and stroke severity remained constant., Conclusion: During the lockdown period in 2020, the number of patients with emergent symptoms remained constant, while fewer patients with urgent symptoms presented to the nER. This may imply behavioral changes in care-seeking behavior., (© 2020 The Authors. European Journal of Neurology published by John Wiley & Sons Ltd on behalf of European Academy of Neurology.)
- Published
- 2021
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27. EndoVAscular treatment and ThRombolysis for Ischemic Stroke Patients (EVA-TRISP) registry: basis and methodology of a pan-European prospective ischaemic stroke revascularisation treatment registry.
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Nordanstig A, Curtze S, Gensicke H, Zinkstok SM, Erdur H, Karlsson C, Karlsson JE, Martinez-Majander N, Sibolt G, Lyrer P, Traenka C, Baharoglu MI, Scheitz JF, Bricout N, Hénon H, Leys D, Eskandari A, Michel P, Hametner C, Ringleb PA, Arnold M, Fischer U, Sarikaya H, Seiffge DJ, Pezzini A, Zini A, Padjen V, Jovanovic DR, Luft A, Wegener S, Kellert L, Feil K, Kägi G, Rentzos A, Lappalainen K, Leker RR, Cohen JE, Gomori J, Brehm A, Liman J, Psychogios M, Kastrup A, Papanagiotou P, Gralla J, Magoni M, Majoie CBLM, Bohner G, Vukasinovic I, Cvetic V, Weber J, Kulcsar Z, Bendszus M, Möhlenbruch M, Ntaios G, Kapsalaki E, Jood K, Nolte CH, Nederkoorn PJJ, Engelter S, Strbian D, and Tatlisumak T
- Subjects
- Humans, Fibrinolytic Agents therapeutic use, Registries, Thrombectomy, Thrombolytic Therapy, Treatment Outcome, Brain Ischemia drug therapy, Endovascular Procedures, Ischemic Stroke, Stroke drug therapy
- Abstract
Purpose: The Thrombolysis in Ischemic Stroke Patients (TRISP) collaboration was a concerted effort initiated in 2010 with the purpose to address relevant research questions about the effectiveness and safety of intravenous thrombolysis (IVT). The collaboration also aims to prospectively collect data on patients undergoing endovascular treatment (EVT) and hence the name of the collaboration was changed from TRISP to EVA-TRISP. The methodology of the former TRISP registry for patients treated with IVT has already been published. This paper focuses on describing the EVT part of the registry., Participants: All centres committed to collecting predefined variables on consecutive patients prospectively. We aim for accuracy and completeness of the data and to adapt local databases to investigate novel research questions. Herein, we introduce the methodology of a recently constructed academic investigator-initiated open collaboration EVT registry built as an extension of an existing IVT registry in patients with acute ischaemic stroke (AIS)., Findings to Date: Currently, the EVA-TRISP network includes 20 stroke centres with considerable expertise in EVT and maintenance of high-quality hospital-based registries. Following several successful randomised controlled trials (RCTs), many important clinical questions remain unanswered in the (EVT) field and some of them will unlikely be investigated in future RCTs. Prospective registries with high-quality data on EVT-treated patients may help answering some of these unanswered issues, especially on safety and efficacy of EVT in specific patient subgroups., Future Plans: This collaborative effort aims at addressing clinically important questions on safety and efficacy of EVT in conditions not covered by RCTs. The TRISP registry generated substantial novel data supporting stroke physicians in their daily decision making considering IVT candidate patients. While providing observational data on EVT in daily clinical practice, our future findings may likewise be hypothesis generating for future research as well as for quality improvement (on EVT). The collaboration welcomes participation of further centres willing to fulfill the commitment and the outlined requirements., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2021. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)
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- 2021
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28. Maintenance of Acute Stroke Care Service During the COVID-19 Pandemic Lockdown.
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Altersberger VL, Stolze LJ, Heldner MR, Henon H, Martinez-Majander N, Hametner C, Nordanstig A, Zini A, Nannoni S, Gonçalves B, Nolte CH, Baumgartner P, Kastrup A, Papanagiotou P, Kägi G, Leker RR, Zedde M, Padovani A, Pezzini A, Padjen V, Cereda CW, Ntaios G, Bonati LH, Rinkel LA, Fischer U, Scheitz JF, Wegener S, Turc G, Michel P, Gentile M, Rentzos A, Ringleb PA, Curtze S, Cordonnier C, Arnold M, Nederkoorn PJ, Engelter ST, and Gensicke H
- Subjects
- Aged, Aged, 80 and over, Cardiology organization & administration, Cohort Studies, Critical Care, Europe epidemiology, Female, Humans, Male, Middle Aged, Pandemics, Physical Distancing, Registries, Severity of Illness Index, Stroke prevention & control, Thrombolytic Therapy, Time-to-Treatment, Treatment Outcome, COVID-19 epidemiology, Hospitalization, Stroke epidemiology, Stroke therapy
- Abstract
[Figure: see text].
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- 2021
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29. Age-Dependent Differences in the Rate and Symptoms of TIA Mimics in Patients Presenting With a Suspected TIA to a Neurological Emergency Room.
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Ippen FM, Walter F, Hametner C, Gumbinger C, Nagel S, Purrucker JC, and Mundiyanapurath S
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Background: Transient ischemic attack (TIA) needs further diagnostic evaluation to prevent future ischemic stroke. However, prophylaxis can be harmful in elderly if the diagnosis is wrong. We aimed at characterizing differences in TIA mimics in younger and older patients to enhance diagnostic accuracy in elderly patients. Methods: In a dedicated neurological emergency room (nER) of a tertiary care University hospital, patients with transient neurological symptoms suspicious of TIA (<24 h) were retrospectively analyzed regarding their final diagnoses and their symptoms. These parameters were compared between patients aged 18-70 and >70 years using descriptive, univariable, and multivariable statistics. Results: From November 2018 until August 2019, 386 consecutive patients were included. 271 (70%) had cardiovascular risk factors and all patients received cerebral imaging, mostly CT [376 (97%)]. There was no difference in the rate of diagnosed TIA between the age groups [85 (46%) vs. 58 (39%); p = 0.213].TIA mimics in the elderly were more often internal medicine diseases [35 (19%) vs. 7 (5%); p < 0.001] and epileptic seizures [48 (26%) vs. 24 (16%); p = 0.032] but less often migraine [2 (1%) vs. 20 (13%); p < 0.001]. The most frequent symptoms in all patients were aphasia and dysarthria [107 (28%) and 92 (24%)]. Sensory impairments were less frequent in elderly patients [23 (11%) vs. 54 (30%); p < 0.001]. Impaired consciousness and orientation were independent predictors for TIA mimics ( p < 0.001) whereas facial palsy ( p < 0.001) motor weakness ( p < 0.001), dysarthria ( p = 0.022) and sensory impairment ( p < 0.001) were independent predictors of TIA. Conclusion: TIA mimics in elderly patients are more likely to be internal medicine diseases and epilepsy compared to younger patients. Excluding internal medicine diseases seems to be important in elderly patients. Facial palsy, motor weakness, dysarthria and sensory impairment are associated with TIA., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Ippen, Walter, Hametner, Gumbinger, Nagel, Purrucker and Mundiyanapurath.)
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- 2021
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30. Estimation of exogenous drivers to predict COVID-19 pandemic using a method from nonlinear control theory.
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Hametner C, Kozek M, Böhler L, Wasserburger A, Du ZP, Kölbl R, Bergmann M, Bachleitner-Hofmann T, and Jakubek S
- Abstract
The currently ongoing COVID-19 pandemic confronts governments and their health systems with great challenges for disease management. Epidemiological models play a crucial role, thereby assisting policymakers to predict the future course of infections and hospitalizations. One difficulty with current models is the existence of exogenous and unmeasurable variables and their significant effect on the infection dynamics. In this paper, we show how a method from nonlinear control theory can complement common compartmental epidemiological models. As a result, one can estimate and predict these exogenous variables requiring the reported infection cases as the only data source. The method allows to investigate how the estimates of exogenous variables are influenced by non-pharmaceutical interventions and how imminent epidemic waves could already be predicted at an early stage. In this way, the concept can serve as an "epidemometer" and guide the optimal timing of interventions. Analyses of the COVID-19 epidemic in various countries demonstrate the feasibility and potential of the proposed approach. The generic character of the method allows for straightforward extension to different epidemiological models., Competing Interests: Conflicts of interestThe authors declare that they have no conflict of interest., (© The Author(s) 2021.)
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- 2021
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31. Prior Dual Antiplatelet Therapy and Thrombolysis in Acute Stroke.
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Altersberger VL, Sturzenegger R, Räty S, Hametner C, Scheitz JF, Moulin S, van den Berg SA, Zini A, Nannoni S, Heldner MR, Jovanovic DR, Martinez-Majander N, Tiainen M, Valkonen K, Berberich A, Erdur H, Cordonnier C, Peters N, Gopisingh KM, Bigliardi G, Strambo D, De Marchis GM, Ntaios G, Cereda CW, Wegener S, Kägi G, Pezzini A, Padjen V, Arnold M, Michel P, Vandelli L, Nederkoorn PJ, Leys D, Nolte CH, Ringleb PA, Curtze S, Engelter ST, and Gensicke H
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- Fibrinolysis, Humans, Thrombolytic Therapy, Platelet Aggregation Inhibitors, Stroke
- Published
- 2020
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32. Radiation exposure per thrombectomy attempt in modern endovascular stroke treatment in the anterior circulation.
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Weyland CS, Seker F, Potreck A, Hametner C, Ringleb PA, Möhlenbruch MA, Bendszus M, and Pfaff JAR
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- Aged, Female, Humans, Male, Middle Cerebral Artery, Radiation Exposure, Retrospective Studies, Treatment Outcome, Endovascular Procedures methods, Fluoroscopy methods, Stroke therapy, Surgery, Computer-Assisted methods, Thrombectomy methods
- Abstract
Objective: To quantify radiation exposure (RE) of endovascular stroke treatment (EST) in the anterior circulation per thrombectomy attempt and determine causes for interventions associated with high RE., Methods: A retrospective single-center study of an institutional review board-approved stroke database of patients receiving EST for large vessel occlusions in the anterior circulation between January 2013 and April 2018 to evaluate reference levels (RL) per thrombectomy attempt. ESTs with RE above the RL were analyzed to determine causes for high RE., Results: Overall, n = 544 patients (occlusion location, M1 and M2 segments of the middle cerebral artery 53.5% and 27.2%, carotid artery 17.6%; successful recanalization rate 85.7%) were analyzed. In the overall population, DAP (in Gy cm
2 , median (IQR)) was 113.7 (68.9-181.7) with a median fluoroscopy time of 31 min (IQR, 17-53) and a median of 2 (IQR, 1-4) thrombectomy attempts. RE increased significantly with every thrombectomy attempt (DAP1 , 68.7 (51.2-106.8); DAP2 , 106.4 (84.8-115.6); p value1vs2 , < 0.001; DAP3 , 130.2 (89.1-183.6); p value2vs3 , 0.044; DAP4 , 169.9 (128.4-224.1); p value3vs4 , 0.001; and DAP5 , 227.6 (146.3-294.6); p value4vs5 , 0.019). Procedures exceeding the 90th percentile of the attempt-dependent radiation exposure level were associated with procedural complications (n = 17/52, 29.8%) or a difficult vascular access (n = 8/52, 14%)., Conclusions: Radiation exposure in endovascular stroke treatment is depending on the number of thrombectomy attempts. Radiation exposure doubles when three attempts and triples when five attempts are necessary compared with single-maneuver interventions. Procedural complications and difficult vascular access were associated with a high radiation exposure in this collective., Key Points: • Radiation exposure of endovascular stroke treatment (EST) is dependent on the number of thrombectomy attempts. • Reference levels as means for quality control in hospitals performing endovascular stroke treatment should be defined by the number of thrombectomy attempts-we suggest 107 Gy cm2 , 156 Gy cm2 , 184 Gy cm2 , 244 Gy cm2 , and 295 Gy cm2 for 1 to 5 maneuvers, respectively, for EST of the anterior circulation • Cases with high rates of radiation exposure are associated with periprocedural complications and difficult anatomical access as a probable cause for a high radiation exposure.- Published
- 2020
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33. Live Monitoring of Strain-Promoted Azide Alkyne Cycloadditions in Complex Reaction Environments by Inline ATR-IR Spectroscopy.
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Svatunek D, Eilenberger G, Denk C, Lumpi D, Hametner C, Allmaier G, and Mikula H
- Abstract
The strain-promoted azide alkyne cycloaddition (SPAAC) is a powerful tool for forming covalent bonds between molecules even under physiological conditions, and therefore found broad application in fields ranging from biological chemistry and biomedical research to materials sciences. For many applications, knowledge about reaction kinetics of these ligations is of utmost importance. Kinetics are commonly assessed and studied by NMR measurements. However, these experiments are limited in terms of temperature and restricted to deuterated solvents. By using an inline ATR-IR probe we show that the cycloaddition of azides and alkynes can be monitored in aqueous and even complex biological fluids enabling the investigation of reaction kinetics in various solvents and even human blood plasma under controlled conditions in low reaction volumes., (© 2020 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA.)
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- 2020
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34. Association of prestroke metformin use, stroke severity, and thrombolysis outcome.
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Westphal LP, Widmer R, Held U, Steigmiller K, Hametner C, Ringleb P, Curtze S, Martinez-Majander N, Tiainen M, Nolte CH, Scheitz JF, Erdur H, Polymeris AA, Traenka C, Eskandari A, Michel P, Heldner MR, Arnold M, Zini A, Vandelli L, Coutinho JM, Groot AE, Padjen V, Jovanovic DR, Bejot Y, Brenière C, Turc G, Seners P, Pezzini A, Magoni M, Leys D, Gilliot S, Scherrer MJ, Kägi G, Luft AR, Gensicke H, Nederkoorn P, Tatlisumak T, Engelter ST, and Wegener S
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- Aged, Diabetes Mellitus, Type 2 drug therapy, Female, Fibrinolytic Agents therapeutic use, Humans, Male, Middle Aged, Retrospective Studies, Thrombolytic Therapy methods, Hypoglycemic Agents therapeutic use, Metformin therapeutic use, Recovery of Function drug effects, Stroke drug therapy, Stroke mortality, Stroke physiopathology
- Abstract
Objective: To evaluate whether pretreatment with metformin (MET) is associated with less stroke severity and better outcome after IV thrombolysis (IVT), we analyzed a cohort of 1,919 patients with stroke with type 2 diabetes mellitus in a multicenter exploratory analysis., Methods: Data from patients with diabetes and ischemic stroke treated with IVT were collected within the European Thrombolysis in Ischemic Stroke Patients (TRISP) collaboration. We applied propensity score matching (PSM) to obtain balanced baseline characteristics of patients treated with and without MET., Results: Of 1,919 patients with stroke with type 2 diabetes who underwent IVT, 757 (39%) had received MET before stroke (MET+), whereas 1,162 (61%) had not (MET-). MET+ patients were younger with a male preponderance. Hypercholesterolemia and pretreatment with statins, antiplatelets, or antihypertensives were more common in the MET+ group. After PSM, the 2 groups were well balanced with respect to demographic and clinical aspects. Stroke severity on admission (NIH Stroke Scale 10.0 ± 6.7 vs 11.3 ± 6.5), 3-month degree of independence on modified Rankin Scale (2 [interquartile range (IQR) 1.0-4.0] vs 3 [IQR 1.0-4.0]), as well as mortality (12.5% vs 18%) were significantly lower in the MET+ group. The frequency of symptomatic intracerebral hemorrhages did not differ between groups. HbA1c levels were well-balanced between the groups., Conclusions: Patients with stroke and diabetes on treatment with MET receiving IVT had less severe strokes on admission and a better functional outcome at 3 months. This suggests a protective effect of MET resulting in less severe strokes as well as beneficial thrombolysis outcome., (© 2020 American Academy of Neurology.)
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- 2020
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35. Effect of haemoglobin levels on outcome in intravenous thrombolysis-treated stroke patients.
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Altersberger VL, Kellert L, Al Sultan AS, Martinez-Majander N, Hametner C, Eskandari A, Heldner MR, van den Berg SA, Zini A, Padjen V, Kägi G, Pezzini A, Polymeris A, DeMarchis GM, Tiainen M, Räty S, Nannoni S, Jung S, Zonneveld TP, Maffei S, Bonati L, Lyrer P, Sibolt G, Ringleb PA, Arnold M, Michel P, Curtze S, Nederkoorn PJ, Engelter ST, and Gensicke H
- Abstract
Introduction: Alterations in haemoglobin levels are frequent in stroke patients. The prognostic meaning of anaemia and polyglobulia on outcomes in patients treated with intravenous thrombolysis is ambiguous., Patients and Methods: In this prospective multicentre, intravenous thrombolysis register-based study, we compared haemoglobin levels on hospital admission with three-month poor outcome (modified Rankin Scale 3-6), mortality and symptomatic intracranial haemorrhage (European Cooperative Acute Stroke Study II-criteria (ECASS-II-criteria)). Haemoglobin level was used as continuous and categorical variable distinguishing anaemia (female: <12 g/dl; male: <13 g/dl) and polyglobulia (female: >15.5 g/dl; male: >17 g/dl). Anaemia was subdivided into mild and moderate/severe (female/male: <11 g/dl). Normal haemoglobin level (female: 12.0-15.5 g/dl, male: 13.0-17.0 g/dl) served as reference group. Unadjusted and adjusted odds ratios with 95% confidence intervals were calculated with logistic regression models., Results: Among 6866 intravenous thrombolysis-treated stroke patients, 5448 (79.3%) had normal haemoglobin level, 1232 (17.9%) anaemia - of those 903 (13.2%) had mild and 329 (4.8%) moderate/severe anaemia - and 186 (2.7%) polyglobulia. Anaemia was associated with poor outcome (OR
adjusted 1.25 (1.05-1.48)) and mortality (ORadjusted 1.58 (1.27-1.95)). In anaemia subgroups, both mild and moderate/severe anaemia independently predicted poor outcome (ORadjusted 1.29 (1.07-1.55) and 1.48 (1.09-2.02)) and mortality (ORadjusted 1.45 (1.15-1.84) and ORadjusted 2.00 (1.46-2.75)). Each haemoglobin level decrease by 1 g/dl independently increased the risk of poor outcome (ORadjusted 1.07 (1.02-1.11)) and mortality (ORadjusted 1.08 (1.02-1.15)). Anaemia was not associated with occurrence of symptomatic intracranial haemorrhage. Polyglobulia did not change any outcome., Discussion: The more severe the anaemia, the higher the probability of poor outcome and death. Severe anaemia might be a target for interventions in hyperacute stroke., Conclusion: Anaemia on admission, but not polyglobulia, is a strong and independent predictor of poor outcome and mortality in intravenous thrombolysis-treated stroke patients., (© European Stroke Organisation 2019.)- Published
- 2020
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36. Symmetric Mixed Sulfur-Selenium Fused Ring Systems as Potential Materials for Organic Field-Effect Transistors.
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Holzer B, Dellago B, Thamm AK, Mathis T, Stöger B, Horkel E, Hametner C, Batlogg B, Fröhlich J, and Lumpi D
- Abstract
A reliable synthetic protocol toward a series of fused chalcogenopheno[1]benzochalcogenophene (CBC) building blocks was developed based on a Fiesselmann reaction. The obtained CBC units were applied in McMurry and Stille coupling reactions toward symmetric regioisomeric ene-linked dimers. These π-conjugated compounds were characterized regarding their photophysical and electrochemical properties and proved to be materials with reduced HOMO-LUMO gaps compared to their sulfur-based analogues. Single-crystal X-ray diffraction experiments revealed strong intermolecular selenium-selenium and selenium-carbon interactions depending on the position and number of incorporated selenium atoms. Good field-effect transistor performance with charge carrier mobilities up to 4×10
-3 cm2 V-1 s-1 and high on/off ratios could be observed., (© 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)- Published
- 2020
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37. Intravenous thrombolysis for suspected ischemic stroke with seizure at onset.
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Polymeris AA, Curtze S, Erdur H, Hametner C, Heldner MR, Groot AE, Zini A, Béjot Y, Dietrich A, Martinez-Majander N, von Rennenberg R, Gumbinger C, Schaedelin S, De Marchis GM, Thilemann S, Traenka C, Lyrer PA, Bonati LH, Wegener S, Ringleb PA, Tatlisumak T, Nolte CH, Scheitz JF, Arnold M, Strbian D, Nederkoorn PJ, Gensicke H, and Engelter ST
- Subjects
- Aged, Aged, 80 and over, Brain Ischemia complications, Brain Ischemia drug therapy, Brain Ischemia mortality, Female, Humans, Male, Middle Aged, Prognosis, Seizures mortality, Stroke mortality, Thrombolytic Therapy mortality, Treatment Outcome, Seizures etiology, Stroke complications, Stroke drug therapy, Thrombolytic Therapy methods
- Abstract
Objective: Seizure at onset (SaO) has been considered a relative contraindication for intravenous thrombolysis (IVT) in patients with acute ischemic stroke, although this appraisal is not evidence based. Here, we investigated the prognostic significance of SaO in patients treated with IVT for suspected ischemic stroke., Methods: In this multicenter, IVT-registry-based study we assessed the association between SaO and symptomatic intracranial hemorrhage (sICH, European Cooperative Acute Stroke Study II definition), 3-month mortality, and 3-month functional outcome on the modified Rankin Scale (mRS) using unadjusted and adjusted logistic regression, coarsened exact matching, and inverse probability weighted analyses., Results: Among 10,074 IVT-treated patients, 146 (1.5%) had SaO. SaO patients had significantly higher National Institutes of Health Stroke Scale score and glucose on admission, and more often female sex, prior stroke, and prior functional dependence than non-SaO patients. In unadjusted analysis, they had generally less favorable outcomes. After controlling for confounders in adjusted, matched, and weighted analyses, all associations between SaO and any of the outcomes disappeared, including sICH (odds ratio [OR]
unadjusted = 1.53 [95% confidence interval (CI) = 0.74-3.14], ORadjusted = 0.52 [95% CI = 0.13-2.16], ORmatched = 0.68 [95% CI = 0.15-3.03], ORweighted = 0.95 [95% CI = 0.39-2.32]), mortality (ORunadjusted = 1.49 [95% CI = 1.00-2.24], ORadjusted = 0.98 [95% CI = 0.5-1.92], ORmatched = 1.13 [95% CI = 0.55-2.33], ORweighted = 1.17 [95% CI = 0.73-1.88]), and functional outcome (mRS ≥ 3/ordinal mRS: ORunadjusted = 1.33 [95% CI = 0.96-1.84]/1.35 [95% CI = 1.01-1.81], ORadjusted = 0.78 [95% CI = 0.45-1.32]/0.78 [95% CI = 0.52-1.16], ORmatched = 0.75 [95% CI = 0.43-1.32]/0.45 [95% CI = 0.10-2.06], ORweighted = 0.87 [95% CI = 0.57-1.34]/1.00 [95% CI = 0.66-1.52]). These results were consistent regardless of whether patients had an eventual diagnosis of ischemic stroke (89/146) or stroke mimic (57/146 SaO patients)., Interpretation: SaO was not an independent predictor of poor prognosis. Withholding IVT from patients with assumed ischemic stroke presenting with SaO seems unjustified. ANN NEUROL 2019;86:770-779., (© 2019 American Neurological Association.)- Published
- 2019
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38. 2-O-Benzyloxycarbonyl protected glycosyl donors: a revival of carbonate-mediated anchimeric assistance for diastereoselective glycosylation.
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Weber J, Svatunek D, Krauter S, Tegl G, Hametner C, Kosma P, and Mikula H
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By reviving an old idea, we demonstrate that alkoxycarbonyl groups can be used in glycosylation reactions to achieve full stereocontrol through participation of a carbonate moiety at O-2. Various benzyloxycarbonyl-protected glycosyl donors were prepared and used for efficient 1,2-trans glycosylation of base-labile compounds and the synthesis of glycosyl esters.
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- 2019
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39. Zearalenone and ß-Zearalenol But Not Their Glucosides Inhibit Heat Shock Protein 90 ATPase Activity.
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Torres Acosta JA, Michlmayr H, Shams M, Schweiger W, Wiesenberger G, Mitterbauer R, Werner U, Merz D, Hauser MT, Hametner C, Varga E, Krska R, Berthiller F, and Adam G
- Abstract
The mycotoxin zearalenone (ZEN) is produced by many plant pathogenic Fusarium species. It is well known for its estrogenic activity in humans and animals, but whether ZEN has a role in plant-pathogen interaction and which process it is targeting in planta was so far unclear. We found that treatment of Arabidopsis thaliana seedlings with ZEN induced transcription of the AtHSP90.1 gene. This heat shock protein (HSP) plays an important role in plant-pathogen interaction, assisting in stability and functionality of various disease resistance gene products. Inhibition of HSP90 ATPase activity impairs functionality. Because HSP90 inhibitors are known to induce HSP90 gene expression and due to the structural similarity with the known HSP90 inhibitor radicicol (RAD), we tested whether ZEN and its phase I metabolites α- and ß-zearalenol are also HSP90 ATPase inhibitors. Indeed, At HSP90.1 and wheat Ta HSP90-2 were inhibited by ZEN and ß-zearalenol, while α-zearalenol was almost inactive. Plants can efficiently glycosylate ZEN and α/ß-zearalenol. We therefore tested whether glucosylation has an effect on the inhibitory activity of these metabolites. Expression of the A. thaliana glucosyltransferase UGT73C6 conferred RAD resistance to a sensitive yeast strain. Glucosylation of RAD, ZEN, and α/ß-zearalenol abolished the in vitro inhibitory activity with recombinant HSP90 purified from Escherichia coli . In conclusion, the mycotoxin ZEN has a very prominent target in plants, HSP90, but it can be inactivated by glycosylation. This may explain why there is little evidence for a virulence function of ZEN in host plants., (Copyright © 2019 Torres Acosta, Michlmayr, Shams, Schweiger, Wiesenberger, Mitterbauer, Werner, Merz, Hauser, Hametner, Varga, Krska, Berthiller and Adam.)
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- 2019
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40. The Fusarium metabolite culmorin suppresses the in vitro glucuronidation of deoxynivalenol.
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Woelflingseder L, Warth B, Vierheilig I, Schwartz-Zimmermann H, Hametner C, Nagl V, Novak B, Šarkanj B, Berthiller F, Adam G, and Marko D
- Subjects
- Animals, Biotransformation, Cell Line, Cell-Free System, Female, Gene Expression Regulation, Enzymologic drug effects, Glucuronides urine, Glucuronosyltransferase biosynthesis, Glucuronosyltransferase genetics, Humans, Inactivation, Metabolic, Male, Microsomes, Liver drug effects, Microsomes, Liver metabolism, Rats, Rats, Sprague-Dawley, Swine, Trichothecenes toxicity, Fusarium metabolism, Glucuronides metabolism, Sesquiterpenes pharmacology, Trichothecenes metabolism
- Abstract
Glucuronidation is a major phase II conjugation pathway in mammals, playing an important role in the detoxification and biotransformation of xenobiotics including mycotoxins such as deoxynivalenol (DON). Culmorin (CUL), a potentially co-occurring Fusarium metabolite, was recently found to inhibit the corresponding detoxification reaction in plants, namely DON-glucoside formation, raising the question whether CUL might affect also the mammalian counterpart. Using cell-free conditions, CUL when present equimolar (67 µM) or in fivefold excess, suppressed DON glucuronidation by human liver microsomes, reducing the formation of DON-15-glucuronide by 15 and 50%, and DON-3-glucuronide by 30 and 50%, respectively. Substantial inhibitory effects on DON glucuronidation up to 100% were found using the human recombinant uridine 5'-diphospho-glucuronosyltransferases (UGT) 2B4 and 2B7, applying a tenfold excess of CUL (100 µM). In addition, we observed the formation of a novel metabolite of CUL, CUL-11-glucuronide, identified for the first time in vitro as well as in vivo in piglet and human urine samples. Despite the observed potency of CUL to inhibit glucuronidation, no significant synergistic toxicity on cell viability was observed in combinations of CUL (0.1-100 µM) and DON (0.01-10 µM) in HT-29 and HepG2 cells, presumably reflecting the limited capacity of the tested cell lines for DON glucuronidation. However, in humans, glucuronidation is known to represent the main detoxification pathway for DON. The present results, including the identification of CUL-11-glucuronide in urine samples of piglets and humans, underline the necessity of further studies on the relevance of CUL as a potentially co-occurring modulator of DON toxicokinetics in vivo.
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- 2019
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41. Metabolism of nivalenol and nivalenol-3-glucoside in rats.
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Schwartz-Zimmermann HE, Binder SB, Hametner C, Miró-Abella E, Schwarz C, Michlmayr H, Reiterer N, Labudova S, Adam G, and Berthiller F
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- Animals, Biotransformation, Feces chemistry, Glucosides metabolism, Glucosides toxicity, Glucuronides metabolism, Leukocyte Count, Male, Mycotoxins pharmacokinetics, Rats, Rats, Sprague-Dawley, Trichothecenes pharmacokinetics, Trichothecenes toxicity, Mycotoxins metabolism, Trichothecenes metabolism
- Abstract
Plant-derived mycotoxin conjugates like deoxynivalenol-3-glucoside can be partly hydrolyzed to their aglycones in vivo, albeit to different extent depending on the mycotoxin conjugate and on the animal species. The aim of this work was to investigate the metabolization of the trichothecene mycotoxin nivalenol (NIV) and the fate of its modified form NIV-3-glucoside (NIV3G) in rats. To that end, 350 μg/kg body weight of NIV and the equimolar dose of NIV3G were administered to six rats by gavage in a 5 × 6 design and excreta were collected for 2 days after each treatment. For further analysis of NIV and NIV3G metabolites in rat urine and feces, seven novel NIV- and NIV3G metabolites including NIV sulfonates (NIVS) 1, 2 and 3, deepoxy-NIV (DNIV), DNIV sulfonate 2, NIV3G sulfonate (NIV3GS) 2 and NIV-3-glucuronide were produced, isolated and characterized. Subsequently, LC-MS/MS based methods for determination of NIV, NIV3G and their metabolites in excreta samples were developed, validated and applied. The biological recoveries of administered toxins in the form of their fecal and urinary metabolites were 57 ± 21% for NIV and 94 ± 36% for NIV3G. The majority of NIV and NIV3G metabolites was excreted into feces, with DNIV and NIVS 2 as major NIV metabolites and NIV3GS 2 and DNIV as major metabolites of NIV3G. Only 1.5% of the administered NIV3G was recovered in urine, with NIV3G itself as major urinary metabolite. The biological recovery of free NIV in urine was approximately 30 times lower after treatment with NIV3G than after administration of NIV, indicating that exposure of rats to NIV3G results in lower toxicity than exposure to NIV., (Copyright © 2019 The Author(s). Published by Elsevier B.V. All rights reserved.)
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- 2019
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42. Untargeted LC-MS based 13 C labelling provides a full mass balance of deoxynivalenol and its degradation products formed during baking of crackers, biscuits and bread.
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Stadler D, Lambertini F, Bueschl C, Wiesenberger G, Hametner C, Schwartz-Zimmermann H, Hellinger R, Sulyok M, Lemmens M, Schuhmacher R, Suman M, Berthiller F, and Krska R
- Subjects
- Carbon Isotopes, Chromatography, Liquid methods, Isotope Labeling, Reproducibility of Results, Trichothecenes metabolism, Bread analysis, Food Contamination analysis, Tandem Mass Spectrometry methods, Trichothecenes analysis
- Abstract
Deoxynivalenol (DON) is considered to be one of the most important contaminants in cereals and food commodities produced thereof. So far it is not clear i) to which extent DON is degraded during baking and ii) if a degradation results in reduced toxicity. We have elucidated the fate of DON during baking of crackers, biscuits and bread, which were produced from fortified dough and processed under pilot plant conditions. Untargeted stable isotope assisted liquid chromatography (LC) high resolution mass spectrometry was used to determine all extractable degradation products. Targeted LC - tandem mass spectrometry based quantification revealed that DON was partially degraded to isoDON (1.3-3.9%), norDON B (0.2-0.9%) and norDON C (0.3-1.2%). A DON degradation of 6% (crackers), 5% (biscuits) and 2% (bread), respectively, was observed. In vitro translation experiments indicate that isoDON is less toxic than DON., (Copyright © 2018 Elsevier Ltd. All rights reserved.)
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- 2019
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43. Correction to: Glucuronidation of deoxynivalenol (DON) by different animal species: identification of iso-DON glucuronides and iso-deepoxy-DON glucuronides as novel DON metabolites in pigs, rats, mice, and cows.
- Author
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Schwartz-Zimmermann HE, Hametner C, Nagl V, Fiby I, Macheiner L, Winkler J, Dänicke S, Clark E, Pestka JJ, and Berthiller F
- Abstract
The original article can be found online.
- Published
- 2018
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44. Cohort profile: Thrombolysis in Ischemic Stroke Patients (TRISP): a multicentre research collaboration.
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Scheitz JF, Gensicke H, Zinkstok SM, Curtze S, Arnold M, Hametner C, Pezzini A, Turc G, Zini A, Padjen V, Wegener S, Nordanstig A, Kellert L, Kägi G, Bejot Y, Michel P, Leys D, Nolte CH, Nederkoorn PJ, and Engelter ST
- Subjects
- Administration, Intravenous, Brain Ischemia complications, Endovascular Procedures adverse effects, Fibrinolytic Agents adverse effects, Humans, Intersectoral Collaboration, Prospective Studies, Stroke etiology, Brain Ischemia therapy, Fibrinolytic Agents therapeutic use, Registries, Stroke therapy, Thrombectomy adverse effects
- Abstract
Purpose: The ThRombolysis in Ischemic Stroke Patients (TRISP) collaboration aims to address clinically relevant questions about safety and outcomes of intravenous thrombolysis (IVT) and endovascular thrombectomy. The findings can provide observational information on treatment of patients derived from everyday clinical practice., Participants: TRISP is an open, investigator-driven collaborative research initiative of European stroke centres with expertise in treatment with revascularisation therapies and maintenance of hospital-based registries. All participating centres made a commitment to prospectively collect data on consecutive patients with stroke treated with IVT using standardised definitions of variables and outcomes, to assure accuracy and completeness of the data and to adapt their local databases to answer novel research questions., Findings to Date: Currently, TRISP comprises 18 centres and registers >10 000 IVT-treated patients. Prior TRISP projects provided evidence on the safety and functional outcome in relevant subgroups of patients who were excluded, under-represented or not specifically addressed in randomised controlled trials (ie, pre-existing disability, cervical artery dissections, stroke mimics, prior statin use), demonstrated deficits in organisation of acute stroke care (ie, IVT during non-working hours, effects of onset-to-door time on onset-to-needle time), evaluated the association between laboratory findings on outcome after IVT and served to develop risk estimation tools for prediction of haemorrhagic complications and functional outcome after IVT., Future Plans: Further TRISP projects to increase knowledge of the effect and safety of revascularisation therapies in acute stroke are ongoing. TRISP welcomes participation and project proposals of further centres fulfilling the outlined requirements. In the future, TRISP will be extended to include patients undergoing endovascular thrombectomy., Competing Interests: Competing interests: JFS has received speaker honoraria from W L Gore & Associates GmbH and travel support from Bayer and Boehringer-Ingelheim; HG has received research support from the Swiss National Science Foundation; AZ has received funding for speaker honoraria and consulting fees from Boehringer-Ingelheim and Medtronic-Covidien and consulting fees from Nestec; GK received grants from Swiss Parkinson Association, Swiss Heart Association, Swiss National Science Foundation and served on advisory boards for Boehringer-Ingelheim, Bayer, Daiichi Sankyo (Schweiz) AG, Zambon, Nestle, GE Healthcare within the last two years; YB received honoraria or consulting fees from AstraZeneca France, Daiichi-Sankyo, BMS-Pfizer, Covidiem, Bayer and MSD France; PM received research grants from the Swiss National Science Foundation, the Swiss Heart Foundation; speaker fees from Boehringer-Ingelheim, Bayer, Covidien and Stryker; honoraria from scientific advisory boards from Boehringer-Ingelheim, Bayer, Pfizer, Amgen; consulting fees from Pierre-Fabre and Astra-Zeneca; and travel support from Boehringer-Ingelheim and Bayer. All this support is received by the institution (CHUV) and is used for stroke education and research; DL participated during the last 5 years to 1 advisory boards, symposia or trials sponsored by Sanofi Aventis, BMS, Astrazeneca, Boeringher-Ingelheim, Servier, Ebewe, CoLucid Pharm, Brainsgate, Photothera, Lundbeck, GSK, Bayer, Pfizer et Allergan (honorarium paid to Adrinord or research account of the hospital) and was an associated editor of the Journal of neurology, neurosurgery and psychiatry 2004-2010 (personal financial compensation); CHN has received funding for travel or speaker honoraria from Bayer, Boehringer-Ingelheim, Takeda, and BMS/Pfizer; PJN has received consulting fees from Boehringer-Ingelheim; STE has received funding for travel or speaker honoraria from Bayer and Boehringer-Ingelheim, he has served on scientific advisory boards for Bayer, Boehringer-Ingelheim, BMS/Pfizer and Covidien and on the editorial board of Stroke. He has received an educational grant from Pfizer and research support from the Science Funds (Wissenschaftsfonds) of the University Hospital Basel, the University Basel, the Swiss Heart Foundation and the Swiss National Science Foundation., (© Author(s) (or their employer(s)) 2018. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)
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- 2018
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45. Non-office-hours admission affects intravenous thrombolysis treatment times and clinical outcome.
- Author
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Zonneveld TP, Curtze S, Zinkstok SM, Gensicke H, Moulin S, Scheitz JF, Seiffge DJ, Hametner C, Heldner MR, Traenka C, Erdur H, Baharoglu I, Martinez-Majander N, Pezzini A, Zini A, Padjen V, Correia PN, Strbian D, Michel P, Béjot Y, Arnold M, Leys D, Ringleb PA, Tatlisumak T, Nolte CH, Engelter ST, and Nederkoorn PJ
- Subjects
- Aged, Aged, 80 and over, Cohort Studies, Female, Humans, Male, Middle Aged, Time Factors, Treatment Outcome, Patient Admission, Stroke drug therapy, Thrombolytic Therapy, Time-to-Treatment
- Abstract
Competing Interests: Competing interests: None declared.
- Published
- 2018
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46. Chemical Glucosylation of Labile Natural Products Using a (2-Nitrophenyl)acetyl-Protected Glucosyl Acetimidate Donor.
- Author
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Weber J, Schwarz M, Schiefer A, Hametner C, Häubl G, Fröhlich J, and Mikula H
- Abstract
The synthesis of (2-nitrophenyl)acetyl (NPAc)-protected glucosyl donors is described that were designed for the neighboring-group assisted glucosylation of base-labile natural products also being sensitive to hydrogenolysis. Glycosylation conditions were optimized using a trichloroacetimidate glucosyl donor, and cyclohexylmethanol and (+)-menthol as model acceptors. The approach was then extended to a one-pot procedure for the synthesis of 1,2- trans -glycosides. This method was finally applied for improved synthesis of the masked mycotoxin T2- O -β,d-glucoside.
- Published
- 2018
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47. Chemical synthesis of culmorin metabolites and their biologic role in culmorin and acetyl-culmorin treated wheat cells.
- Author
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Weber J, Vaclavikova M, Wiesenberger G, Haider M, Hametner C, Fröhlich J, Berthiller F, Adam G, Mikula H, and Fruhmann P
- Subjects
- Cells, Cultured, Fusarium metabolism, Glucose chemistry, Glycosylation, Magnetic Resonance Spectroscopy, Mycotoxins pharmacology, Sesquiterpenes metabolism, Stereoisomerism, Sulfates chemistry, Triticum cytology, Sesquiterpenes chemical synthesis, Sesquiterpenes pharmacology, Triticum drug effects
- Abstract
The Fusarium metabolite culmorin (1) is receiving increased attention as an "emerging mycotoxin". It co-occurs with trichothecene mycotoxins and potentially influences their toxicity. Its ecological role and fate in plants is unknown. We synthesized sulfated and glucosylated culmorin conjugates as potential metabolites, which are expected to be formed in planta, and used them as reference compounds. An efficient procedure for the synthesis of culmorin sulfates was developed. Diastereo- and regioselective glucosylation of culmorin (1) was achieved by exploiting or preventing unexpected acyl transfer when using different glucosyl donors. The treatment of a wheat suspension culture with culmorin (1) revealed an in planta conversion of culmorin into culmorin-8-glucoside (6) and culmorin acetate, but no sulfates or culmorin-11-glucoside (7) was found. The treatment of wheat cells with the fungal metabolite 11-acetylculmorin (2) revealed its rapid deacetylation, but also showed the formation of 11-acetylculmorin-8-glucoside (8). These results show that plants are capable of extensively metabolizing culmorin.
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- 2018
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48. UDP-Glucosyltransferases from Rice, Brachypodium, and Barley: Substrate Specificities and Synthesis of Type A and B Trichothecene-3-O-β-d-glucosides.
- Author
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Michlmayr H, Varga E, Malachová A, Fruhmann P, Piątkowska M, Hametner C, Šofrová J, Jaunecker G, Häubl G, Lemmens M, Berthiller F, and Adam G
- Subjects
- Brachypodium enzymology, Glucosides metabolism, Glycosyltransferases metabolism, Hordeum enzymology, Oryza enzymology, Plant Proteins metabolism, Trichothecenes metabolism
- Abstract
Trichothecene toxins are confirmed or suspected virulence factors of various plant-pathogenic Fusarium species. Plants can detoxify these to a variable extent by glucosylation, a reaction catalyzed by UDP-glucosyltransferases (UGTs). Due to the unavailability of analytical standards for many trichothecene-glucoconjugates, information on such compounds is limited. Here, the previously identified deoxynivalenol-conjugating UGTs HvUGT13248 (barley), OsUGT79 (rice) and Bradi5g03300 ( Brachypodium ), were expressed in E. coli , affinity purified, and characterized towards their abilities to glucosylate the most relevant type A and B trichothecenes. HvUGT13248, which prefers nivalenol over deoxynivalenol, is also able to conjugate C-4 acetylated trichothecenes (e.g., T-2 toxin) to some degree while OsUGT79 and Bradi5g03300 are completely inactive with C-4 acetylated derivatives. The type A trichothecenes HT-2 toxin and T-2 triol are the kinetically preferred substrates in the case of HvUGT13248 and Bradi5g03300. We glucosylated several trichothecenes with OsUGT79 (HT-2 toxin, T-2 triol) and HvUGT13248 (T-2 toxin, neosolaniol, 4,15-diacetoxyscirpenol, fusarenon X) in the preparative scale. NMR analysis of the purified glucosides showed that exclusively β-D-glucosides were formed regio-selectively at position C-3-OH of the trichothecenes. These synthesized standards can be used to investigate the occurrence and toxicological properties of these modified mycotoxins., Competing Interests: The authors declare no conflict of interest.
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- 2018
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49. Less-toxic rearrangement products of NX-toxins are formed during storage and food processing.
- Author
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Varga E, Wiesenberger G, Woelflingseder L, Twaruschek K, Hametner C, Vaclaviková M, Malachová A, Marko D, Berthiller F, and Adam G
- Subjects
- Cell Survival drug effects, Colon cytology, Colon drug effects, Food Contamination analysis, Food Microbiology, Food Storage, Fusarium metabolism, HT29 Cells, Hot Temperature, Humans, Hydrogen-Ion Concentration, Molecular Structure, Structure-Activity Relationship, Edible Grain chemistry, Edible Grain microbiology, Food Handling, Fusarium growth & development, Trichothecenes chemistry, Trichothecenes isolation & purification, Trichothecenes toxicity
- Abstract
A new type A trichothecene mycotoxin, NX-2, was previously reported to be produced by North American isolates of the cereal pathogen Fusarium graminearum. Here we describe the isolation and structural characterization of a rearrangement product, called NX2-M1, and related compounds with different acetylation patterns (NX3-M1 and NX4-M1). In the NX-M1 derivatives, the epoxide ring is opened, and a covalent bridge between C-10 and C-12 of the trichothecene backbone is formed. In vitro translation assays showed that NX3-M1 is less toxic for eukaryotic ribosomes than NX-3. NX3-M1 also has a greatly reduced cytotoxic potential on two tested human colon cell lines. Formation of NX3-M1 can therefore be regarded as a detoxification reaction. The related F. graminearum mycotoxin deoxynivalenol (DON), which is frequently occurring worldwide, is very stable during food processing. Testing NX-3 at different pH-values and temperature conditions, as well as under conditions that simulate the storage of infected grains and bread-making process, revealed a strongly reduced stability of NX-3 and concurrent formation of NX3-M1. Although the NX-3 formed in planta is as toxic as DON, the extensive formation of the non-toxic rearrangement product should be taken into account for risk assessment of this emerging food contaminant., (Copyright © 2017 The Author(s). Published by Elsevier B.V. All rights reserved.)
- Published
- 2018
- Full Text
- View/download PDF
50. Intravenous thrombolysis and platelet count.
- Author
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Gensicke H, Al Sultan AS, Strbian D, Hametner C, Zinkstok SM, Moulin S, Bill O, Zini A, Padjen V, Kägi G, Pezzini A, Seiffge DJ, Traenka C, Räty S, Amiri H, Zonneveld TP, Lachenmeier R, Polymeris A, Roos YB, Gumbinger C, Jovanovic DR, Curtze S, Sibolt G, Vandelli L, Ringleb PA, Leys D, Cordonnier C, Michel P, Lyrer PA, Peters N, Tatlisumak T, Nederkoorn PJ, and Engelter ST
- Subjects
- Administration, Intravesical, Aged, Aged, 80 and over, Female, Humans, Male, Middle Aged, Platelet Count, Prospective Studies, Registries, Risk Factors, Stroke epidemiology, Survival Analysis, Thrombocytopenia epidemiology, Thrombocytosis epidemiology, Hemorrhage epidemiology, Stroke blood, Stroke drug therapy, Thrombolytic Therapy adverse effects
- Abstract
Objective: To study the effect of platelet count (PC) on bleeding risk and outcome in stroke patients treated with IV thrombolysis (IVT) and to explore whether withholding IVT in PC < 100 × 10
9 /L is supported., Methods: In this prospective multicenter, IVT register-based study, we compared PC with symptomatic intracranial hemorrhage (sICH; Second European-Australasian Acute Stroke Study [ECASS II] criteria), poor outcome (modified Rankin Scale score 3-6), and mortality at 3 months. PC was used as a continuous and categorical variable distinguishing thrombocytopenia (<150 × 109 /L), thrombocytosis (>450 × 109 /L), and normal PC (150-450 × 109 /L [reference group]). Moreover, PC < 100 × 109 /L was compared to PC ≥ 100 × 109 /L. Unadjusted and adjusted odds ratios (ORs) with 95% confidence intervals (CIs) from the logistic regression models were calculated., Results: Among 7,533 IVT-treated stroke patients, 6,830 (90.7%) had normal PC, 595 (7.9%) had thrombocytopenia, and 108 (1.4%) had thrombocytosis. Decreasing PC (every 10 × 109 /L) was associated with increasing risk of sICH (ORadjusted 1.03, 95% CI 1.02-1.05) but decreasing risk of poor outcome (ORadjusted 0.99, 95% CI 0.98-0.99) and mortality (ORadjusted 0.98, 95% CI 0.98-0.99). The risk of sICH was higher in patients with thrombocytopenic than in patients with normal PC (ORadjusted 1.73, 95% CI 1.24-2.43). However, the risk of poor outcome (ORadjusted 0.89, 95% CI 0.39-1.97) and mortality (ORadjusted 1.09, 95% CI 0.83-1.44) did not differ significantly. Thrombocytosis was associated with mortality (ORadjusted 2.02, 95% CI 1.21-3.37). Forty-four (0.3%) patients had PC < 100 × 109 /L. Their risks of sICH (ORunadjusted 1.56, 95% CI 0.48-5.07), poor outcome (ORadjusted 1.63, 95% CI 0.82-3.24), and mortality (ORadjusted 1.38, 95% CI 0.64-2.98) did not differ significantly from those of patients with PC ≥ 100 × 109 /L., Conclusion: Lower PC was associated with increased risk of sICH, while higher PC indicated increased mortality. Our data suggest that PC modifies outcome and complications in individual patients, while withholding IVT in all patients with PC < 100 × 109 /L is challenged., (© 2018 American Academy of Neurology.)- Published
- 2018
- Full Text
- View/download PDF
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