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Flom E, Krychowiak M, Schmitz O, König R, Barbui T, Henke F, Jakubowski M, Kwak S, Loch S, Muñoz Burgos J, Svensson J. Bayesian modeling of collisional-radiative models applicable to thermal helium beam plasma diagnostics. Nuclear Materials and Energy 2022. [DOI: 10.1016/j.nme.2022.101269] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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2
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Lee E, Kwak S, Shin H. EP13.01-005 Role of Artificial Intelligence on Chest Radiographs for Detecting Resectable Early Lung Cancer. J Thorac Oncol 2022. [DOI: 10.1016/j.jtho.2022.07.925] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
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3
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Beidler CD, Smith HM, Alonso A, Andreeva T, Baldzuhn J, Beurskens MNA, Borchardt M, Bozhenkov SA, Brunner KJ, Damm H, Drevlak M, Ford OP, Fuchert G, Geiger J, Helander P, Hergenhahn U, Hirsch M, Höfel U, Kazakov YO, Kleiber R, Krychowiak M, Kwak S, Langenberg A, Laqua HP, Neuner U, Pablant NA, Pasch E, Pavone A, Pedersen TS, Rahbarnia K, Schilling J, Scott ER, Stange T, Svensson J, Thomsen H, Turkin Y, Warmer F, Wolf RC, Zhang D. Publisher Correction: Demonstration of reduced neoclassical energy transport in Wendelstein 7-X. Nature 2021; 598:E5. [PMID: 34642470 PMCID: PMC8550957 DOI: 10.1038/s41586-021-04023-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- C D Beidler
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany.
| | - H M Smith
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
| | - A Alonso
- Laboratorio Nacional de Fusion, CIEMAT, Madrid, Spain
| | - T Andreeva
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
| | - J Baldzuhn
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
| | | | - M Borchardt
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
| | - S A Bozhenkov
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
| | - K J Brunner
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
| | - H Damm
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
| | - M Drevlak
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
| | - O P Ford
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
| | - G Fuchert
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
| | - J Geiger
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
| | - P Helander
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
| | - U Hergenhahn
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany.,Fritz-Haber-Institut der Max-Planck-Gesellschaft, Berlin, Germany
| | - M Hirsch
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
| | - U Höfel
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
| | - Ye O Kazakov
- Laboratory for Plasma Physics (LPP), École royale militaire/Koninklijke Militaire School (ERM/KMS), Brussels, Belgium
| | - R Kleiber
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
| | - M Krychowiak
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
| | - S Kwak
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
| | - A Langenberg
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
| | - H P Laqua
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
| | - U Neuner
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
| | - N A Pablant
- Princeton Plasma Physics Laboratory, Princeton, NJ, USA
| | - E Pasch
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
| | - A Pavone
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
| | - T S Pedersen
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
| | - K Rahbarnia
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
| | - J Schilling
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
| | - E R Scott
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
| | - T Stange
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
| | - J Svensson
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
| | - H Thomsen
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
| | - Y Turkin
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
| | - F Warmer
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
| | - R C Wolf
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
| | - D Zhang
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
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Kwak S, Park JB. Impact of atrial fibrillation on the progression and outcomes of isolated mild functional tricuspid regurgitation. Eur Heart J 2021. [DOI: 10.1093/eurheartj/ehab724.1702] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Abstract
Background
Atrial fibrillation (AF) is increasingly recognized as a cause of tricuspid regurgitation (TR) in the structurally normal tricuspid valve. However, there are limited data regarding the impact of AF on TR progression and its long-term cardiovascular outcomes.
Purpose
We aimed to investigate the association of AF with the significant TR progression and its impact on clinical outcomes among patients with isolated mild functional TR.
Methods
We studied 834 patients with mild function TR identified on the echocardiography between 2007 and 2019, whose follow-up echocardiography beyond 1-year was available. Major exclusion criteria were the overt causes of primary and secondary TR (i.e., concomitant left-sided heart disease). Primary endpoint was the significant TR progression to more than a moderate degree on the follow-up echocardiography. Composite cardiac event was defined as cardiovascular death, TR surgery, and heart failure admission due to TR.
Results
Of 834 patients with isolated mild functional TR (mean age 65.6 years, 41% men), 292 (35.0%) patients had AF at the baseline. Patients with AF were older and had larger left atrium compared to those without. During the median of 4.55 years follow-up (interquartile interval 2.56–7.24 years), 36 patients developed a significant TR ≥ moderate degree. The cumulative rate of TR progression was significantly higher in patients with AF than those without (11.3% versus 0.6%, P<0.001) (Figure 1). Multivariable Cox analyses showed that AF was associated with a 3-fold higher risk of TR progression (adjusted hazard ratio 3.50, 95% confidence interval 1.42–8.65). Regarding the cardiovascular outcomes, patients who developed significant TR had a higher rate of composite cardiac events compared to those who did not (cardiac events: 38.9% versus 6.3% P<0.001) (Figure 2).
Conclusions
AF is a strong risk factor for TR progression among patients with isolated mild functional TR. In addition, the development of significant TR is associated with worse cardiovascular outcomes. These findings highlight the important pathophysiology of AF on TR development and its clinical consequences.
Funding Acknowledgement
Type of funding sources: None.
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Affiliation(s)
- S Kwak
- Seoul National University Hospital, Seoul, Korea (Republic of)
| | - J B Park
- Seoul National University Hospital, Seoul, Korea (Republic of)
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Lee S, Kwak S, Park T, Son B, Yun HJ, Hur J, Yoo H. Synthesis of Lead-Free CaTiO 3 Oxide Perovskite Film through Solution Combustion Method and Its Thickness-Dependent Hysteresis Behaviors within 100 mV Operation. Molecules 2021; 26:molecules26185446. [PMID: 34576916 PMCID: PMC8471917 DOI: 10.3390/molecules26185446] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2021] [Revised: 08/31/2021] [Accepted: 09/02/2021] [Indexed: 11/26/2022] Open
Abstract
Perovskite is attracting considerable interest because of its excellent semiconducting properties and optoelectronic performance. In particular, lead perovskites have been used extensively in photovoltaic, photodetectors, thin-film transistors, and various electronic applications. On the other hand, the elimination of lead is essential because of its strong toxicity. This paper reports the synthesis of lead-free calcium titanate perovskite (CaTiO3) using a solution-processed combustion method. The chemical and morphological properties of CaTiO3 were examined as a function of its thickness by scanning electron microscopy, X-ray diffraction (XRD), atomic force microscopy, X-ray photoelectron spectroscopy, and ultraviolet–visible spectrophotometry. The analysis showed that thicker films formed by a cumulative coating result in larger grains and more oxygen vacancies. Furthermore, thickness-dependent hysteresis behaviors were examined by fabricating a metal-CaTiO3-metal structure. The electrical hysteresis could be controlled over an extremely low voltage operation, as low as 100 mV, by varying the grain size and oxygen vacancies.
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Affiliation(s)
- Subin Lee
- Department of Electronic Engineering, Gachon University, Seongnam 13120, Korea; (S.L.); (S.K.)
| | - Soyeon Kwak
- Department of Electronic Engineering, Gachon University, Seongnam 13120, Korea; (S.L.); (S.K.)
| | - Taehyun Park
- Department of Chemical and Biological Engineering, Gachon University, Seongnam 13120, Korea;
| | - Byoungchul Son
- Research Center for Materials Analysis, Korea Basic Science Institute (KBSI), Daejeon 34133, Korea; (B.S.); (H.J.Y.)
| | - Hyung Joong Yun
- Research Center for Materials Analysis, Korea Basic Science Institute (KBSI), Daejeon 34133, Korea; (B.S.); (H.J.Y.)
| | - Jaehyun Hur
- Department of Chemical and Biological Engineering, Gachon University, Seongnam 13120, Korea;
- Correspondence: (J.H.); (H.Y.)
| | - Hocheon Yoo
- Department of Electronic Engineering, Gachon University, Seongnam 13120, Korea; (S.L.); (S.K.)
- Correspondence: (J.H.); (H.Y.)
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Beidler CD, Smith HM, Alonso A, Andreeva T, Baldzuhn J, Beurskens MNA, Borchardt M, Bozhenkov SA, Brunner KJ, Damm H, Drevlak M, Ford OP, Fuchert G, Geiger J, Helander P, Hergenhahn U, Hirsch M, Höfel U, Kazakov YO, Kleiber R, Krychowiak M, Kwak S, Langenberg A, Laqua HP, Neuner U, Pablant NA, Pasch E, Pavone A, Pedersen TS, Rahbarnia K, Schilling J, Scott ER, Stange T, Svensson J, Thomsen H, Turkin Y, Warmer F, Wolf RC, Zhang D. Demonstration of reduced neoclassical energy transport in Wendelstein 7-X. Nature 2021; 596:221-226. [PMID: 34381232 PMCID: PMC8357633 DOI: 10.1038/s41586-021-03687-w] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2020] [Accepted: 06/02/2021] [Indexed: 02/07/2023]
Abstract
Research on magnetic confinement of high-temperature plasmas has the ultimate goal of harnessing nuclear fusion for the production of electricity. Although the tokamak1 is the leading toroidal magnetic-confinement concept, it is not without shortcomings and the fusion community has therefore also pursued alternative concepts such as the stellarator. Unlike axisymmetric tokamaks, stellarators possess a three-dimensional (3D) magnetic field geometry. The availability of this additional dimension opens up an extensive configuration space for computational optimization of both the field geometry itself and the current-carrying coils that produce it. Such an optimization was undertaken in designing Wendelstein 7-X (W7-X)2, a large helical-axis advanced stellarator (HELIAS), which began operation in 2015 at Greifswald, Germany. A major drawback of 3D magnetic field geometry, however, is that it introduces a strong temperature dependence into the stellarator's non-turbulent 'neoclassical' energy transport. Indeed, such energy losses will become prohibitive in high-temperature reactor plasmas unless a strong reduction of the geometrical factor associated with this transport can be achieved; such a reduction was therefore a principal goal of the design of W7-X. In spite of the modest heating power currently available, W7-X has already been able to achieve high-temperature plasma conditions during its 2017 and 2018 experimental campaigns, producing record values of the fusion triple product for such stellarator plasmas3,4. The triple product of plasma density, ion temperature and energy confinement time is used in fusion research as a figure of merit, as it must attain a certain threshold value before net-energy-producing operation of a reactor becomes possible1,5. Here we demonstrate that such record values provide evidence for reduced neoclassical energy transport in W7-X, as the plasma profiles that produced these results could not have been obtained in stellarators lacking a comparably high level of neoclassical optimization.
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Affiliation(s)
- C D Beidler
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany.
| | - H M Smith
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
| | - A Alonso
- Laboratorio Nacional de Fusion, CIEMAT, Madrid, Spain
| | - T Andreeva
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
| | - J Baldzuhn
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
| | | | - M Borchardt
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
| | - S A Bozhenkov
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
| | - K J Brunner
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
| | - H Damm
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
| | - M Drevlak
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
| | - O P Ford
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
| | - G Fuchert
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
| | - J Geiger
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
| | - P Helander
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
| | - U Hergenhahn
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
- Fritz-Haber-Institut der Max-Planck-Gesellschaft, Berlin, Germany
| | - M Hirsch
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
| | - U Höfel
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
| | - Ye O Kazakov
- Laboratory for Plasma Physics (LPP), École royale militaire/Koninklijke Militaire School (ERM/KMS), Brussels, Belgium
| | - R Kleiber
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
| | - M Krychowiak
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
| | - S Kwak
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
| | - A Langenberg
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
| | - H P Laqua
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
| | - U Neuner
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
| | - N A Pablant
- Princeton Plasma Physics Laboratory, Princeton, NJ, USA
| | - E Pasch
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
| | - A Pavone
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
| | - T S Pedersen
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
| | - K Rahbarnia
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
| | - J Schilling
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
| | - E R Scott
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
| | - T Stange
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
| | - J Svensson
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
| | - H Thomsen
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
| | - Y Turkin
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
| | - F Warmer
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
| | - R C Wolf
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
| | - D Zhang
- Max-Planck-Institut für Plasmaphysik, Greifswald, Germany
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Pavone A, Svensson J, Krychowiak M, Hergenhahn U, Winters V, Kornejew P, Kwak S, Hoefel U, Koenig R, Wolf RC. Neural network surrogates of Bayesian diagnostic models for fast inference of plasma parameters. Rev Sci Instrum 2021; 92:033531. [PMID: 33820062 DOI: 10.1063/5.0043772] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/11/2021] [Accepted: 02/28/2021] [Indexed: 06/12/2023]
Abstract
We present a framework for training artificial neural networks (ANNs) as surrogate Bayesian models for the inference of plasma parameters from diagnostic data collected at nuclear fusion experiments, with the purpose of providing a fast approximation of conventional Bayesian inference. Because of the complexity of the models involved, conventional Bayesian inference can require tens of minutes for analyzing one single measurement, while hundreds of thousands can be collected during a single plasma discharge. The ANN surrogates can reduce the analysis time down to tens/hundreds of microseconds per single measurement. The core idea is to generate the training data by sampling them from the joint probability distribution of the parameters and observations of the original Bayesian model. The network can be trained to learn the reconstruction of plasma parameters from observations and the model joint probability distribution from plasma parameters and observations. Previous work has validated the application of such a framework to the former case at the Wendelstein 7-X and Joint European Torus experiments. Here, we first give a description of the general methodological principles allowing us to generate the training data, and then we show an example application of the reconstruction of the joint probability distribution of an effective ion charge Zeff-bremsstrahlung model from data collected at the latest W7-X experimental campaign. One key feature of such an approach is that the network is trained exclusively on data generated with the Bayesian model, requiring no experimental data. This allows us to replicate the training scheme and generate fast, surrogate ANNs for any validated Bayesian diagnostic model.
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Affiliation(s)
- A Pavone
- Max-Planck-Institute for Plasma Physics, Greifswald 17491, Germany
| | - J Svensson
- Max-Planck-Institute for Plasma Physics, Greifswald 17491, Germany
| | - M Krychowiak
- Max-Planck-Institute for Plasma Physics, Greifswald 17491, Germany
| | - U Hergenhahn
- Max-Planck-Institute for Plasma Physics, Greifswald 17491, Germany
| | - V Winters
- Max-Planck-Institute for Plasma Physics, Greifswald 17491, Germany
| | - P Kornejew
- Max-Planck-Institute for Plasma Physics, Greifswald 17491, Germany
| | - S Kwak
- Max-Planck-Institute for Plasma Physics, Greifswald 17491, Germany
| | - U Hoefel
- Max-Planck-Institute for Plasma Physics, Greifswald 17491, Germany
| | - R Koenig
- Max-Planck-Institute for Plasma Physics, Greifswald 17491, Germany
| | - R C Wolf
- Max-Planck-Institute for Plasma Physics, Greifswald 17491, Germany
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Kwak S, Everett R, Ko T, Lee H, Lee W, Treibel T, Chin C, Captur G, Schulz-Menger J, Newby D, Greenwood J, Moon J, Dweck M, Lee S. Stratifying the prognostic capability of cardiovascular magnetic resonance in severe aortic stenosis: a machine learning approach. Eur Heart J 2020. [DOI: 10.1093/ehjci/ehaa946.0230] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Abstract
Background
Cardiovascular magnetic resonance (CMR) demonstrates promise in improving patient risk stratification in aortic stenosis (AS). We explored whether machine learning might provide further insights into the prognostic capability of CMR parameters.
Methods
Severe AS patients (n=440) undergoing AVR were prospectively enrolled across 10 international sites, and CMR performed prior to AVR. A machine learning prediction model using a random survival forest (RSF) was trained with 29 variables, including 13 CMR, 4 echocardiography, and 12 clinical parameters, using post-AVR mortality as an outcome. The impact of the important variables on the outcome (partial dependency) was examined.
Results
The most predictive CMR parameters in the RSF model were the extracellular volume fraction (ECV%), followed by right ventricular ejection fraction (RVEF), late gadolinium enhancement (LGE%), and indexed left ventricular end-diastolic volume (LVEDVi). Regarding the partial effects, the predicted mortality increased strongly once the ECV% exceeded 26.5% (Figure 1A). The LGE% was associated with an increased risk of mortality, which reached a plateau beyond the level of 2% (Figure 1C). There were U-shaped relationships between mortality and both RVEF and LVEDVi, with the lowest mortality seen at RVEF 70% and LVEDVi 68ml/m2 (Figure 1B, D). These trends of predicted outcomes by each variable were verified in the Kaplan-Meier curves and Cox analyses (Table). In both Cox and RSF models, the predictability was substantially increased when these four CMR parameters were added to conventional clinical risk factors. An AS-CMR risk score comprised of these four parameters presented a stepwise increase in mortality with increasing adverse CMR features (p<0.001).
Conclusions
Our machine learning analysis using RSF has identified ECV%, RVEF, LGE%, and LVEDVi as key prognostic markers in severe AS with a nonlinear influence of each parameter on mortality post-AVR.
Figure 1
Funding Acknowledgement
Type of funding source: Public grant(s) – National budget only. Main funding source(s): This study was supported by grants from the Korean Health Technology R & D Project, Ministry of Health, Welfare & Family Affairs, Republic of Korea (HI16C0225 and HI15C0399) and the National Institute for Health Research (NIHR) infrastructure at Leeds.
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Affiliation(s)
- S Kwak
- Seoul National University Hospital, Seoul, Korea (Republic of)
| | - R Everett
- University of Edinburgh, Edinburgh, United Kingdom
| | - T Ko
- Seoul National University Hospital, Seoul, Korea (Republic of)
| | - H Lee
- Seoul National University Hospital, Seoul, Korea (Republic of)
| | - W Lee
- Seoul National University Hospital, Seoul, Korea (Republic of)
| | - T Treibel
- Barts Health NHS Trust, London, United Kingdom
| | - C Chin
- National Heart Centre Singapore, Singapore, Singapore
| | - G Captur
- Royal Free Hospital, London, United Kingdom
| | | | - D Newby
- University of Edinburgh, Edinburgh, United Kingdom
| | | | - J Moon
- Barts Health NHS Trust, London, United Kingdom
| | - M.R Dweck
- University of Edinburgh, Edinburgh, United Kingdom
| | - S.P Lee
- Seoul National University Hospital, Seoul, Korea (Republic of)
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9
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Kwak S, Choi YS, Na HG, Bae CH, Song SY, Kim YD. Fipronil upregulates inflammatory cytokines and MUC5AC expression in human nasal epithelial cells. Rhinology 2020; 58:66-73. [PMID: 31680128 DOI: 10.4193/rhin19.172] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
BACKGROUND Airway inflammation and excessive mucin production are pathophysiological characteristics of airway diseases. Fipronil, a pesticide, is being extensively used in agriculture and veterinary medicine worldwide. However, this compound impairs immune function in non-target organisms. The present study aimed to evaluate the effect of fipronil on pro-inflammatory cytokine and mucus production and signalling pathways in human primary nasal METHODOLOGY: The effect of fipronil on pro-inflammatory cytokine and MUC5AC expression and the signalling pathway of fipronil were investigated using real-time PCR, enzyme immunoassays, immunofluorescence, and immunoblot analysis with specific inhibitors and small interfering RNA. RESULTS Fipronil treatment increased pro-inflammatory cytokine interleukin (IL)-1beta, IL-6, IL-8, and MUC5AC expression in human primary nasal epithelial cells. It also induced phosphorylation of extracellular signal-regulated kinase 1/2 (ERK1/2) mitogenactivated protein kinase (MAPK), p38 MAPK, and nuclear factor kappa-light-chain-enhancer of activated B cells (NF-kB). MAPK and NF-kB inhibitor treatment significantly inhibited increases in IL-1beta, IL-6, IL-8, and MUC5AC expression. Ex vivo data confirmed that fipronil-induced MUC5AC expression occurs through ERK1/2, p38, and NF-kB signalling pathways in nasal inferior turbinate tissue. CONCLUSIONS Fipronil induced pro-inflammatory cytokine IL-1beta, IL-6, IL-8, and MUC5AC expression via ERK1/2 MAPK, p38 MAPK, and NF-kB in human primary nasal epithelial cells.
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Affiliation(s)
- S Kwak
- Department of Medical Science, College of Medicine, Graduate School of Yeungnam University, Daegu, Republic of Korea; Department of Otorhinolaryngology-Head and Neck Surgery, College of Medicine, Yeungnam University, Daegu, Republic of Korea
| | - Y S Choi
- Department of Otorhinolaryngology-Head and Neck Surgery, College of Medicine, Yeungnam University, Daegu, Republic of Korea
| | - H G Na
- Department of Otorhinolaryngology-Head and Neck Surgery, College of Medicine, Yeungnam University, Daegu, Republic of Korea
| | - C H Bae
- Department of Otorhinolaryngology-Head and Neck Surgery, College of Medicine, Yeungnam University, Daegu, Republic of Korea
| | - S-Y Song
- Department of Otorhinolaryngology-Head and Neck Surgery, College of Medicine, Yeungnam University, Daegu, Republic of Korea
| | - Y-D Kim
- Department of Otorhinolaryngology-Head and Neck Surgery, College of Medicine, Yeungnam University, Daegu, Republic of Korea; Regional Center for Respiratory Diseases, Yeungnam University Medical Center, Daegu, Republic of Korea
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10
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Park Y, Kwon K, Kwak J, Kwak S, Yang D, Pontes D, Zhang M, Xu S, Rogers J. 826 Ultra-low profile, soft pressure sensors with wireless communication for wound healing applications. J Invest Dermatol 2020. [DOI: 10.1016/j.jid.2020.03.841] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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11
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Park JB, Park CS, Choi YJ, Kwak S, Moon I, Hwang IC, Park JJ, Lee SP, Park JH, Cho GY. P785 Left ventricular geometry and myocardial contractility modulate impact of statins on prognosis in patients with acute heart failure. Eur Heart J Cardiovasc Imaging 2020. [DOI: 10.1093/ehjci/jez319.444] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Abstract
Funding Acknowledgements
N/A
Background/Introduction: The benefit of statins in patients with heart failure (HF) remains controversial and the mechanism of action is largely speculative. We investigated whether survival benefit with statins differs according to left ventricular (LV) geometry and myocardial contractility in acute HF patients.
Methods
We enrolled 1792 acute HF patients receiving statins and 2296 patients not receiving statins admitted from 2009 to 2016. The LV and right ventricular (RV) global longitudinal strain (GLS) was assessed as a measure of myocardial contractility. Patients were classified into 2 groups based on ischemic etiology of HF and further divided into 4 subgroups according to the median values of LV-GLS or RV-GLS. The primary outcome was 5-year all-cause mortality. The study protocol was approved by the ethics committee at each institute and complied with the Declaration of Helsinki. The need for written informed consent was waived.
Results
During the 5-year follow-up, 1740 (40.4%) patients died and they had more unfavorable baseline characteristics. Statin therapy was significantly associated with improved survival in overall patients and in both groups with and without ischemic etiology (all p <0.001). Patients with concentric remodeling/hypertrophy and eccentric hypertrophy demonstrated survival benefit with statin therapy (P = 0.033, 0.004, and 0.008, respectively), while those with normal geometry did not (p = 0.123). In the non-ischemic HF group, survival benefit with statin therapy was confined to patients with low LV-GLS (p = 0.045) or those with low RV-GLS p = 0.003). On the contrary, in ischemic HF group, survival benefit with statin therapy was observed in all patients regardless of the values of LV-GLS or RV-GLS. Significant interactions were present between statin use and diabetes mellitus and IHD (p for interaction = 0.027 and 0.003, respectively) regarding mortality.
Conclusions
LV geometry and myocardial contractility may modulate the effects of statins in patients with acute HF. These echocardiographic measures can provide prognostic information to guide tailored statin treatment in this population. Our findings may also help to develop more well-designed prospective studies, in terms of a more homogenous study population, to confirm survival benefit with statin therapy.
Abstract P785 Figure. Multivariate Cox survival curves
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Affiliation(s)
- J B Park
- Seoul National University Hospital, Seoul, Korea (Republic of)
| | - C S Park
- Korea Advanced Institute of Science and Technology, Daejeon, Korea (Republic of)
| | - Y J Choi
- Seoul National University Hospital, Seoul, Korea (Republic of)
| | - S Kwak
- Seoul National University Hospital, Seoul, Korea (Republic of)
| | - I Moon
- Seoul National University Hospital, Seoul, Korea (Republic of)
| | - I C Hwang
- Seoul National University Bundang Hospital, Seongnam, Korea (Republic of)
| | - J J Park
- Seoul National University Bundang Hospital, Seongnam, Korea (Republic of)
| | - S P Lee
- Seoul National University Hospital, Seoul, Korea (Republic of)
| | - J H Park
- Chungnam National University Hospital, Daejeon, Korea (Republic of)
| | - G Y Cho
- Seoul National University Bundang Hospital, Seongnam, Korea (Republic of)
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12
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Kwak S, Hwang IC, Park JJ, Park JH, Cho GY, Park JB. P5002The impact of diabetes mellitus on global longitudinal strain of patients with acute heart failure. Eur Heart J 2019. [DOI: 10.1093/eurheartj/ehz746.0180] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Abstract
Introduction
Diabetes mellitus (DM) aggravates the clinical features and the prognosis of heart failure (HF) patients. However, the impact of DM on the ventricular systolic function of HF patients is not well delineated.
Purpose
The present study aimed to investigate the impact of DM on HF, regarding the systolic function presented by the global longitudinal strain (GLS).
Methods
In 4312 patients with acute HF, left ventricle (LV) and right ventricle (RV) GLS were acquired by speckle-tracking echocardiography. HF patients with DM were compared to those without DM from the entire cohort (n=4312), as well as the propensity-score matched cohort (n=3034).
Results
Our cohort consisted of 1750 DM patients (40.6%). Both LV-GLS and LVEF were significantly lower within the patients with DM (10.1±4.8% vs. 11.3±5.1%, p<0.001 for LV-GLS; 39.1±15.5% vs. 41.7±15.6%, p<0.001 for LVEF) in the entire cohort. In the propensity-score matched cohort, LV-GLS was significantly reduced in the patients with DM compared to those without DM (10.2±4.9% vs. 10.9±5.0%, p<0.001), even with the matched LVEF (Table 1). Decreased LV-GLS in the DM patients was consistently identified in both subgroups of preserved EF and reduced EF (Table 1). Although RV-GLS was slightly lower in the patients with DM from the matched cohort, it was not significant in neither the preserved EF nor the reduced EF subgroup. When comparing the adverse outcome in the propensity-score matched cohort, the survival of patients with DM was significantly lower (Figure 1-A, 1-B), except for the preserved EF group (Figure 1-C).
Comparison between heart failure patients with and without diabetes in the matched cohort Matched cohort p-value HFrEF (matched) p-value HFpEF (matched) p-value No-DM (n=1517) DM (n=1517) No-DM (n=823) DM (n=801) No-DM (n=652) DM (n=669) Age, years 71±14 71±11 0.962 69±14 70±11 0.305 75±11 74±10 0.061 Ischemic heart disease, n (%) 545 (35) 575 (37) 0.275 375 (36) 402 (39) 0.238 150 (34) 147 (34) 0.945 GFR, mL/min/1.73m2 56±27 55±27 0.282 58±28 56±27 0.253 54±27 54±26 1.000 HbA1C, % 5.7±0.4 7.3±1.4 <0.001 5.7±0.4 7.3±1.4 <0.001 5.7±0.4 7.2±1.4 <0.001 LV ejection fraction, % 39±15 39±15 0.871 31±9 31±10 0.99 59±5 59±6 0.279 LV-GLS, % 10.9±5.0 10.2±4.9 <0.001 9.1±3.8 8.3±3.6 <0.001 15.5±4.5 14.9±4.5 0.036 RV-GLS, % 13.1±6.5 12.7±6.2 0.045 12.1±6.2 11.8±5.9 0.188 15.6±6.5 15.0±6.4 0.157
Figure 1. Outcome by DM status
Conclusions
DM is associated with the impaired LV systolic function presented by GLS in HF patients, even with the adjustment of LVEF. The result indicates that GLS is a more sensitive marker of systolic function than LVEF, in terms of the DM status among the HF patients.
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Affiliation(s)
- S Kwak
- Seoul National University Hospital, Seoul, Korea (Republic of)
| | - I.-C Hwang
- Seoul National University Bundang Hospital, Seongnam-si, Gyeonggi-do, Korea (Republic of)
| | - J.-J Park
- Seoul National University Bundang Hospital, Seongnam-si, Gyeonggi-do, Korea (Republic of)
| | - J.-H Park
- Seoul National University Bundang Hospital, Seongnam-si, Gyeonggi-do, Korea (Republic of)
| | - G.-Y Cho
- Seoul National University Bundang Hospital, Seongnam-si, Gyeonggi-do, Korea (Republic of)
| | - J.-B Park
- Seoul National University Hospital, Seoul, Korea (Republic of)
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Gatsiou A, Tual-Chalot S, Bonini F, Cesarini V, Ortega-Gomez A, Schook K, Hoffmann J, Kwak S, Selzman CH, Martini M, Dimmeler S, Gallo A, Drakos S, Soehnlein O, Stellos K. 1438MicroRNA editing is integral for interleukin-6 trans-signalling and leukocyte trafficking to ischemic tissues. Eur Heart J 2019. [DOI: 10.1093/eurheartj/ehz748.0073] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Abstract
Background/Aim
Adenosine to inosine RNA editing is an essential post-transcriptional RNA modification catalysed by adenosine deaminase acting on RNA-1 and -2 (ADAR1; ADAR2). Endothelial cells (ECs) attract and guide leukocytes to sites of ischemic tissue injury. Here we studied the role of RNA editing in ischemic disease.
Methods
Primary human and murine vascular endothelial cell cultures were used to assess the EC responses to interleukin-6 (IL-6) or ischemia. For the animal studies, the effect of ADAR2 in acute and chronic ischemic disease was evaluated in cremaster muscle microcirculation by intravital microscopy, in peritoneal cavity after sterile peritonitis and in gastrocnemius muscle after hind-limb ischemia by 8-colour flow cytometry and immunohistochemistry (IHC) studies of Adar2−/−/tg as well as of i(nducible)EC-ADAR2 knockout (KO) mice. For the mechanistic studies, deep RNA sequencing, qRT-PCR, western blot, confocal microscopy, target-specific microRNA (miRNA) editing studies, RNA-immunoprecipitation, miRNA/plasmid silencing/overexpression and luciferase reporter assays were used among others. For human studies, ischemic tissues derived from patients with acute or chronic ischemic heart disease were processed.
Results
ADAR2, but not ADAR1, expression is induced by >2-fold in hypoxic ECs and in ischemic vascular ECs in mice and humans. Unbiased gene ontology analysis of the EC transcriptome indicated that ADAR2 controls inflammatory responses and predominantly the expression of interleukin-6-signal transducer (IL6ST), the co-receptor of IL-6. Subsequently, ADAR2 controls IL-6 trans-signalling in ECs as documented by the STAT3 phosphorylation and expression of the downstream leukocyte adhesion molecules, E-selectin and VCAM-1. IL-6-inflamed cremaster muscles showed that rolling and adhesion of leukocyte subsets to vascular wall were severely impaired in Adar2−/−/tg mice. Leukocyte transmigration was also diminished by >2-fold in Adar2−/−/tg and in iEC-ADAR2 KO mice in response to IL-6 or ischemia. Similar results were obtained for leukocyte rolling, adhesion and infiltration after acute (4h) and chronic (3d; 21d) ischemia from iEC-ADAR2 KO mice and human ischemic muscle tissues. Next we studied how ADAR2 controls IL6ST expression. ADAR2-deficient vascular EC miRNAome revealed the upregulation of a conserved group of miRNAs targeting the IL6ST mRNA including miR-199a-5p and miR-335-3p. At a single-nucleotide level, ADAR2-induced RNA editing of the stem loops of the primary miR-199a1/2 and miR-335 directly disrupted Drosha recruitment to both and thus inhibited their maturation process. Accordingly, rescue experiments using miRNA-inhibitors restored IL6ST levels after ADAR2 deficiency.
Conclusion
Taking together, inhibition of the microRNA maturation process by ADAR2-mediated RNA editing is integral for IL-6 trans-signalling in vascular endothelium and subsequent leukocyte trafficking to ischemic tissues in mice and humans.
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Affiliation(s)
- A Gatsiou
- Newcastle University, Newcastle upon Tyne, United Kingdom
| | - S Tual-Chalot
- Newcastle University, Newcastle upon Tyne, United Kingdom
| | - F Bonini
- Wolfgang Goethe University, Frankfurt am Main, Germany
| | - V Cesarini
- Bambino Gesu Children's Hospital, Rome, Italy
| | - A Ortega-Gomez
- Institute for Cardiovascular Prevention (IPEK), Munich, Germany
| | - K Schook
- Newcastle University, Newcastle upon Tyne, United Kingdom
| | - J Hoffmann
- Wolfgang Goethe University, Frankfurt am Main, Germany
| | - S Kwak
- University of Tokyo, Tokyo, Japan
| | - C H Selzman
- University of Utah, Salt Lake City, United States of America
| | - M Martini
- Polyclinic Agostino Gemelli, Rome, Italy
| | - S Dimmeler
- Wolfgang Goethe University, Frankfurt am Main, Germany
| | - A Gallo
- Bambino Gesu Children's Hospital, Rome, Italy
| | - S Drakos
- University of Utah, Salt Lake City, United States of America
| | - O Soehnlein
- Institute for Cardiovascular Prevention (IPEK), Munich, Germany
| | - K Stellos
- Newcastle University, Newcastle upon Tyne, United Kingdom
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14
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Zhang D, König R, Feng Y, Burhenn R, Brezinsek S, Jakubowski M, Buttenschön B, Niemann H, Pavone A, Krychowiak M, Kwak S, Svensson J, Gao Y, Pedersen TS, Alonso A, Baldzuhn J, Beidler CD, Biedermann C, Bozhenkov S, Brunner KJ, Damm H, Hirsch M, Giannone L, Drewelow P, Effenberg F, Fuchert G, Hammond KC, Höfel U, Killer C, Knauer J, Laqua HP, Laube R, Pablant N, Pasch E, Penzel F, Rahbarnia K, Reimold F, Thomsen H, Winters V, Wagner F, Klinger T. First Observation of a Stable Highly Dissipative Divertor Plasma Regime on the Wendelstein 7-X Stellarator. Phys Rev Lett 2019; 123:025002. [PMID: 31386539 DOI: 10.1103/physrevlett.123.025002] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/17/2019] [Indexed: 06/10/2023]
Abstract
For the first time, the optimized stellarator Wendelstein 7-X has operated with an island divertor. An operation regime in hydrogen was found in which the total plasma radiation approached the absorbed heating power without noticeable loss of stored energy. The divertor thermography recorded simultaneously a strong reduction of the heat load on all divertor targets, indicating almost complete power detachment. This operation regime was stably sustained over several energy confinement times until the preprogrammed end of the discharge. The plasma radiation is mainly due to oxygen and is located at the plasma edge. This plasma scenario is reproducible and robust at various heating powers, plasma densities, and gas fueling locations. These experimental results show that the island divertor concept actually works and displays good power dissipation potential, producing a promising exhaust concept for the stellarator reactor line.
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Affiliation(s)
- D Zhang
- Max-Planck-Institut für Plasmaphysik, 17491 Greifswald, Germany
| | - R König
- Max-Planck-Institut für Plasmaphysik, 17491 Greifswald, Germany
| | - Y Feng
- Max-Planck-Institut für Plasmaphysik, 17491 Greifswald, Germany
| | - R Burhenn
- Max-Planck-Institut für Plasmaphysik, 17491 Greifswald, Germany
| | - S Brezinsek
- Forschungszentrum Jülich GmbH, IEK-4 52425 Jülich, Germany
| | - M Jakubowski
- Max-Planck-Institut für Plasmaphysik, 17491 Greifswald, Germany
| | - B Buttenschön
- Max-Planck-Institut für Plasmaphysik, 17491 Greifswald, Germany
| | - H Niemann
- Max-Planck-Institut für Plasmaphysik, 17491 Greifswald, Germany
| | - A Pavone
- Max-Planck-Institut für Plasmaphysik, 17491 Greifswald, Germany
| | - M Krychowiak
- Max-Planck-Institut für Plasmaphysik, 17491 Greifswald, Germany
| | - S Kwak
- Max-Planck-Institut für Plasmaphysik, 17491 Greifswald, Germany
| | - J Svensson
- Max-Planck-Institut für Plasmaphysik, 17491 Greifswald, Germany
| | - Y Gao
- Forschungszentrum Jülich GmbH, IEK-4 52425 Jülich, Germany
| | - T S Pedersen
- Max-Planck-Institut für Plasmaphysik, 17491 Greifswald, Germany
| | - A Alonso
- Laboratorio Nacional de Fusion CIEMAT, 28040 Madrid, Spain
| | - J Baldzuhn
- Max-Planck-Institut für Plasmaphysik, 17491 Greifswald, Germany
| | - C D Beidler
- Max-Planck-Institut für Plasmaphysik, 17491 Greifswald, Germany
| | - C Biedermann
- Max-Planck-Institut für Plasmaphysik, 17491 Greifswald, Germany
| | - S Bozhenkov
- Max-Planck-Institut für Plasmaphysik, 17491 Greifswald, Germany
| | - K J Brunner
- Max-Planck-Institut für Plasmaphysik, 17491 Greifswald, Germany
| | - H Damm
- Max-Planck-Institut für Plasmaphysik, 17491 Greifswald, Germany
| | - M Hirsch
- Max-Planck-Institut für Plasmaphysik, 17491 Greifswald, Germany
| | - L Giannone
- Max-Planck-Institut für Plasmaphysik, 85748 Garching, Germany
| | - P Drewelow
- Max-Planck-Institut für Plasmaphysik, 17491 Greifswald, Germany
| | - F Effenberg
- University of Wisconsin, Madison, Wisconsin 53706, USA
| | - G Fuchert
- Max-Planck-Institut für Plasmaphysik, 17491 Greifswald, Germany
| | - K C Hammond
- Max-Planck-Institut für Plasmaphysik, 17491 Greifswald, Germany
| | - U Höfel
- Max-Planck-Institut für Plasmaphysik, 17491 Greifswald, Germany
| | - C Killer
- Max-Planck-Institut für Plasmaphysik, 17491 Greifswald, Germany
| | - J Knauer
- Max-Planck-Institut für Plasmaphysik, 17491 Greifswald, Germany
| | - H P Laqua
- Max-Planck-Institut für Plasmaphysik, 17491 Greifswald, Germany
| | - R Laube
- Max-Planck-Institut für Plasmaphysik, 17491 Greifswald, Germany
| | - N Pablant
- Princeton Plasma Physics Laboratory, Princeton, New Jersey 08540, USA
| | - E Pasch
- Max-Planck-Institut für Plasmaphysik, 17491 Greifswald, Germany
| | - F Penzel
- Max-Planck-Institut für Plasmaphysik, 85748 Garching, Germany
| | - K Rahbarnia
- Max-Planck-Institut für Plasmaphysik, 17491 Greifswald, Germany
| | - F Reimold
- Max-Planck-Institut für Plasmaphysik, 17491 Greifswald, Germany
| | - H Thomsen
- Max-Planck-Institut für Plasmaphysik, 17491 Greifswald, Germany
| | - V Winters
- University of Wisconsin, Madison, Wisconsin 53706, USA
| | - F Wagner
- Max-Planck-Institut für Plasmaphysik, 17491 Greifswald, Germany
| | - T Klinger
- Max-Planck-Institut für Plasmaphysik, 17491 Greifswald, Germany
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15
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Affiliation(s)
- H Kim
- Seoul National University
| | - S Kwak
- Seoul National University
| | - J Chey
- Seoul National University
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Pavone A, Svensson J, Langenberg A, Pablant N, Hoefel U, Kwak S, Wolf RC. Bayesian uncertainty calculation in neural network inference of ion and electron temperature profiles at W7-X. Rev Sci Instrum 2018; 89:10K102. [PMID: 30399785 DOI: 10.1063/1.5039286] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/07/2018] [Accepted: 07/16/2018] [Indexed: 06/08/2023]
Abstract
We make use of a Bayesian description of the neural network (NN) training for the calculation of the uncertainties in the NN prediction. Having uncertainties on the NN prediction allows having a quantitative measure for trusting the NN outcome and comparing it with other methods. Within the Bayesian framework, the uncertainties can be calculated under different approximations. The NN has been trained with the purpose of inferring ion and electron temperature profile from measurements of a X-ray imaging diagnostic at W7-X. The NN has been trained in such a way that it constitutes an approximation of a full Bayesian model of the diagnostic, implemented within the Minerva framework. The network has been evaluated using measured data and the uncertainties calculated under different approximations have been compared with each other, finding that neglecting the noise on the NN input can lead to an underestimation of the error bar magnitude in the range of 10%-30%.
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Affiliation(s)
- A Pavone
- Max-Planck-Institute for Plasma Physics, Greifswald 17491, Germany
| | - J Svensson
- Max-Planck-Institute for Plasma Physics, Greifswald 17491, Germany
| | - A Langenberg
- Max-Planck-Institute for Plasma Physics, Greifswald 17491, Germany
| | - N Pablant
- Princenton Plasma Physics Lab, Princeton, New Jersey 08543, USA
| | - U Hoefel
- Max-Planck-Institute for Plasma Physics, Greifswald 17491, Germany
| | - S Kwak
- Max-Planck-Institute for Plasma Physics, Greifswald 17491, Germany
| | - R C Wolf
- Max-Planck-Institute for Plasma Physics, Greifswald 17491, Germany
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17
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Gatsiou A, Soehnlein O, Garcia-Gonzalez C, Ortega-Gomez A, Kwak S, Selzman CH, Braun T, Drakos S, Dimmeler S, Stellos K. 27The RNA editor ADAR2 links inflammation to functional recovery from ischemic diseases. Cardiovasc Res 2018. [DOI: 10.1093/cvr/cvy060.010] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Affiliation(s)
- A Gatsiou
- JW Goethe University, Institute of Cardiovascular Regeneration, Frankfurt am Main, Germany
| | - O Soehnlein
- Institute for Cardiovascular Prevention (IPEK), Munich, Germany
| | - C Garcia-Gonzalez
- Max Planck Institute for Heart and Lung Research, Bad Nauheim, Germany
| | - A Ortega-Gomez
- Institute for Cardiovascular Prevention (IPEK), Munich, Germany
| | - S Kwak
- University of Tokyo, Tokyo, Japan
| | - C H Selzman
- University of Utah, Utah, United States of America
| | - T Braun
- Max Planck Institute for Heart and Lung Research, Bad Nauheim, Germany
| | - S Drakos
- University of Utah, Utah, United States of America
| | - S Dimmeler
- JW Goethe University, Institute of Cardiovascular Regeneration, Frankfurt am Main, Germany
| | - K Stellos
- JW Goethe University, Institute of Cardiovascular Regeneration, Frankfurt am Main, Germany
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18
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Choi G, Kwak S, Lee H, Chang M. Effect of high-frequency repetitive transcranial magnetic stimulation on chronic central pain after mild traumatic brain injury: A pilot study. J Rehabil Med 2018; 50:246-252. [PMID: 29392332 DOI: 10.2340/16501977-2321] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
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20
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Park I, Sun H, Chi H, Kim S, park J, Kwak S, Lee K, Jo J. Frozen thawed Embryo transfer with simple monitoring does not impair IVF outcomes in natural cycles. Fertil Steril 2015. [DOI: 10.1016/j.fertnstert.2015.07.611] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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21
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Sun H, PARK I, Kim S, Kwak S, Lee K, Chi H. Daily luteal phase support enhance pregnancy rates in COH/IUI cycles. Fertil Steril 2015. [DOI: 10.1016/j.fertnstert.2015.07.700] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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22
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Abstract
Spontaneous flexor tendon rupture is a rare condition and the aetiology is not clear. We report 12 elderly Korean farmers with spontaneous flexor tendon ruptures. We found the rupture in the dominant hand in ten patients. A rupture in the little finger was found in all 12 patients (seven with both flexor tendons ruptured and five with only the profundus ruptured), in the ring finger in four patients (the profundus ruptured in all and both flexor tendons in two patients), and in the middle finger a partial rupture of the profundus in one patient. The tendons were ruptured close to the hook of the hamate. Repetitive friction between the flexor tendons and the hamate hook may cause the ruptures. The hamate hook was excised and the ruptured profundus tendons were reconstructed with tendon transfers with quite favourable functional recovery at follow-up of 1 to 2 years. The ruptured superficialis tendons were not reconstructed. Level of Evidence IV.
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Affiliation(s)
- G J Lee
- MS Jaegeon Hospital, Seoul National University Hospital, Seoul, Korea
| | - S Kwak
- Department of Orthopedic Surgery, Seoul National University Hospital, Seoul, Korea
| | - H K Kim
- MS Jaegeon Hospital, Seoul National University Hospital, Seoul, Korea
| | - S H Ha
- MS Jaegeon Hospital, Seoul National University Hospital, Seoul, Korea
| | - H J Lee
- Department of Orthopedic Surgery, Seoul National University Hospital, Seoul, Korea
| | - G H Baek
- Department of Orthopedic Surgery, Seoul National University Hospital, Seoul, Korea
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Jones L, Gusella J, MacDonald M, Wheeler V, Lee JM, Myers R, Latourelle J, Jones L, Harold D, Holmans P, Orth M, Kwak S. A03 Genetic Modifiers Affecting The Age At Motor Onset In Huntington's Disease. J Neurol Psychiatry 2014. [DOI: 10.1136/jnnp-2014-309032.3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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24
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Tillack K, Mack V, Sedaghat Y, Scholz D, Gabrysiak C, Reichelt A, Kottig K, von der Kammer H, Munoz-Sanjuan I, Kwak S. M05 Prevention of Aggregate Formation by RNAI Knockdown of Huntingtin in the Q175 HD Mouse Model. J Neurol Psychiatry 2014. [DOI: 10.1136/jnnp-2014-309032.277] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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25
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Kang S, Lee M, Min J, Chung YJ, Kwak S, Cho H, Kim J, Kim MR. Successfully Removed Focal Adenomyosis by Robot-Assisted Laparoscopic Adenomyomectomy. J Minim Invasive Gynecol 2013. [DOI: 10.1016/j.jmig.2013.08.574] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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27
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Iwata NK, Aoki S, Okabe S, Arai N, Terao Y, Kwak S, Abe O, Kanazawa I, Tsuji S, Ugawa Y. Evaluation of corticospinal tracts in ALS with diffusion tensor MRI and brainstem stimulation. Neurology 2008; 70:528-32. [DOI: 10.1212/01.wnl.0000299186.72374.19] [Citation(s) in RCA: 103] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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28
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Ryu J, Lee H, Cho J, Kwak S, Lee H, Lee M, Lee M, Kim C. Gender difference in susceptibility to smoking in Korean lung cancer patients having smoking habits. J Clin Oncol 2006. [DOI: 10.1200/jco.2006.24.18_suppl.17158] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
17158 Background: There were some controversies whether women were more or less susceptible to the carcinogenic effect of cigarette smoke and the decline of forced expiratory volume in 1 second (FEV1) to pack-years compared to men. Methods: In this study, we included all lung cancer patients having smoking habits who was histologically diagnosed and performed pulmonary function testing at the time of diagnosis from September 2001 through December 2005. We estimated individual susceptibility to smoking using a formula (SI, susceptibility index) of (100% predicted FEV1)/pack-years. Results: Of 858 lung cancer patients, sex ratio (M/F) was 14.6 (803/55). Past smokers were in 236 (29.3%) for men, 11 (20.0%) for women. Most common hsitologic type was squamous cell carcinoma (477), adenocarcinoma (191), small cell carcinoma (147), adenosquamous cell carcinoma (14), large cell carcinoma (14), NSCLC cell type not specified (15). Pack-years were 41.3 ± 18.9 for men, 29.2 ± 20.4 for women (P = 0.000). FEV1 % was 78.7 ± 23.3 for men, 79.4 ± 22.9 for women (P = 0.832). As for SI, there were no differences between men (0.65 ± 1.1) and women (0.72 ± 1.6) (P = 0.688). Conclusions: Although lung cancer women having smoking habits showed lower pack-years, there were no gender differences in terms of FEV1 decline to cigarette smoking. No significant financial relationships to disclose.
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Affiliation(s)
- J. Ryu
- Inha University Hospital, Incheon, Republic of Korea; Social and Preventive Medicine, Incheon, Republic of Korea
| | - H. Lee
- Inha University Hospital, Incheon, Republic of Korea; Social and Preventive Medicine, Incheon, Republic of Korea
| | - J. Cho
- Inha University Hospital, Incheon, Republic of Korea; Social and Preventive Medicine, Incheon, Republic of Korea
| | - S. Kwak
- Inha University Hospital, Incheon, Republic of Korea; Social and Preventive Medicine, Incheon, Republic of Korea
| | - H. Lee
- Inha University Hospital, Incheon, Republic of Korea; Social and Preventive Medicine, Incheon, Republic of Korea
| | - M. Lee
- Inha University Hospital, Incheon, Republic of Korea; Social and Preventive Medicine, Incheon, Republic of Korea
| | - M. Lee
- Inha University Hospital, Incheon, Republic of Korea; Social and Preventive Medicine, Incheon, Republic of Korea
| | - C. Kim
- Inha University Hospital, Incheon, Republic of Korea; Social and Preventive Medicine, Incheon, Republic of Korea
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Abstract
A 66-year-old woman presented with a 3-year history of progressive right-sided hemiparkinsonism manifested by a right-hand resting tremor and right-sided bradykinesia. Magnetic resonance imaging (MRI) of the brain revealed a non-enhanced polycystic mass in the left midbrain. (11)C-methylspiperone ((11)C-NMSP) and (18)F-fluorodopa ((18)F-DOPA) positron emission tomography (PET) revealed a striatal hypometabolism that was restricted to the left side. These findings are consistent with a dysfunction in the left nigrostriatal dopaminergic pathway that is presumably induced by the cystic mass in the left midbrain. This case is significant due to the paucity of reports regarding the occurrence of a relatively pure parkinsonism that is associated with a mesencephalic space-occupying lesion.
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Affiliation(s)
- M Yoshimura
- Department of Neurology, Division of Neuroscience, Graduate School of Medicine, University of Tokyo, Tokyo, Japan.
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Takuma H, Kwak S, Yoshizawa T, Kanazawa I. Reduction of GluR2 RNA editing, a molecular change that increases calcium influx through AMPA receptors, selective in the spinal ventral gray of patients with amyotrophic lateral sclerosis. Ann Neurol 1999; 46:806-15. [PMID: 10589532 DOI: 10.1002/1531-8249(199912)46:6<806::aid-ana2>3.0.co;2-s] [Citation(s) in RCA: 143] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Enhancement of calcium influx through the alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionate (AMPA)/kainate receptor is a plausible mechanism underlying selective neuronal death in amyotrophic lateral sclerosis (ALS). The calcium conductance of the AMPA receptor is regulated by the GluR2 subunit that is edited at the glutamine/arginine residue site in the subunit assembly. We investigated the molecular changes of GluR2 mRNA in the spinal cord of ALS cases, those of cases with other neurological diseases, and those of normal cases using reverse transcription-polymerase chain reaction combined with restriction enzyme cleavage. We found that the editing efficiency was significantly lower only in the ventral gray of ALS cases (virtually 0% in 2 cases) than in any spinal region of the disease controls and normal controls. In addition, expression of GluR2 mRNA is lower in the ventral gray of the ALS cases and disease controls than in that of the normal controls. The above molecular changes of GluR2 mRNA in the ventral gray of ALS cases may enhance calcium influx through AMPA receptors, thereby promoting neuronal vulnerability. The decrement of GluR2 mRNA editing efficiency is unique to the ventral gray of ALS cases and may be closely linked to the etiology of ALS.
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Affiliation(s)
- H Takuma
- Department of Neurology, Graduate School of Medicine, University of Tokyo, Japan
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31
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Abstract
BACKGROUND AND PURPOSE Recent progress in noninvasive imaging techniques has resulted in increased detection of unruptured aneurysms. Although many neurosurgeons advocate surgical intervention for such unruptured aneurysms, the long-term results of surgery for unruptured aneurysms have not been carefully investigated. METHODS We analyzed 173 consecutive patients who had unruptured intracranial saccular aneurysm(s) detected by angiography that was performed for reasons other than subarachnoid hemorrhage (SAH). Of those, 115 cases were surgically treated and studied. All patients were followed up for either SAH, repeat treatment of aneurysms, or death. The median follow-up period was 8.8 years. RESULTS Four of the 115 patients suffered SAH either from a de novo aneurysm (2) or from regrowth of clipped aneurysm (1), or from regrowth after wrapping (1). Additionally, 1 patient also suffered SAH from an unstudied basilar aneurysm. One patient was incidentally found to have de novo aneurysm and underwent reoperation 14 years after the first operation. The cumulative risk for SAH for the 114 cases excluding the basilar aneurysm case was 1.4% in 10 years and 12.4% in 20 years. CONCLUSIONS Although this study confirmed the long-term efficacy of clipping unruptured aneurysms, the risk of SAH was high compared with that in the general population, even after treatment. Considering the high mortality rate of SAH, long-term follow-up by angiography may be warranted for patients with surgically treated unruptured aneurysms.
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Affiliation(s)
- K Tsutsumi
- Department of Neurosurgery, Aizu Chuou Hospital, Aizuwakamatsu, Fukushima, Japan
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32
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Jiang C, Giger ML, Chinander MR, Martell JM, Kwak S, Favus MJ. Characterization of bone quality using computer-extracted radiographic features. Med Phys 1999; 26:872-9. [PMID: 10436887 DOI: 10.1118/1.598604] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
Both bone mineral density (BMD) and trabecular structure are important determinates of bone mechanical properties. However, neither BMD or trabecular structural features can completely explain the variations in bone mechanical properties. In this study, we combine BMD and bone structural features to characterize bone mechanical behavior. Radiographs were obtained from 34 femoral neck specimens excised during total hip arthroplasties. Each neck radiograph was digitized and a region of interest (ROI) was selected from the medial side of the femoral neck. Textural features, the global Minkoswski dimension and trabecular orientation, were extracted from each ROI image using Minkowski dimension analysis. The BMD of each specimen was measured using dual-energy x-ray absorptiometry (DXA) and subsequently normalized by bone size as measured from a standard pelvis radiograph. Mechanical testing was performed on the trabecular bone cubes machined from each femoral neck to yield bone mechanical properties. Multiple regression was performed to select the best features to predict bone mechanical properties. The results suggest that, using multiple predictors including normalized BMD structural features, and patient age, the coefficients of determination (R2) improved over the use of BMD alone. For bone strength, the R2 was improved from 0.24 using conventional BMD to 0.48 using a four-predictor model. Similar results were obtained in the prediction of Young's modulus, i.e., the R2 was improved from 0.25 to 0.55 in going from the model using conventional BMD to a four-predictor model. This study demonstrates the contributions of normalized BMD, structural features, and age to bone mechanical properties, and suggests a potential method for the noninvasive evaluation of bone mechanical properties.
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Affiliation(s)
- C Jiang
- University of Chicago, Illinois 60637, USA
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33
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Abstract
A developmental anomaly of the long head of the biceps tendon was found in a cadaveric shoulder. Findings on arthroscopy, routine MR imaging, and MR arthrography were compared and correlated with results of anatomic dissection. MR arthrography appears to be a very good diagnostic imaging method for depicting this anomaly prior to arthroscopy.
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Affiliation(s)
- L Yeh
- Department of Radiology, Veterans Affairs Medical Center, San Diego, CA, USA
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34
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Abstract
BACKGROUND AND PURPOSE The neck clipping of cerebral aneurysms is a well-established treatment for subarachnoid hemorrhage (SAH) caused by aneurysmal rupture. However, it is still unclear how great a risk of recurrence patients with a successfully treated aneurysm carry over a long-term period. METHODS Of 425 patients with SAH surgically treated in Aizu Chuou Hospital from 1976 to 1994, 220 cases meeting the following criteria were studied: (1) all aneurysms detected by 3- or 4-vessel cerebral angiography were clipped, (2) complete obliteration of aneurysm(s) was confirmed by postoperative angiography, and (3) the patient survived >3 years. All patients were traced until January 1998 for recurrent SAH or death. The mean follow-up period was 9.9 (range, 3 to 21) years. RESULTS Six patients (2.7%) had recurrent SAH, each with an interval ranging from 3 to 17 years (mean, 11 years) since the original treatment. In addition, 2 patients were found to have regrowth of the originally operated aneurysms. The cumulative recurrence rate of SAH, calculated using the Kaplan-Meier method, was 2.2% at 10 years and 9. 0% at 20 years after the original treatment. CONCLUSIONS The recurrence rate was considerably higher than the previously reported risk of SAH in the normal population, and the rate increased with time. These data indicate that patients with ruptured cerebral aneurysms still carry higher risks for SAH in a long-term period, even after complete obliteration of the aneurysm, and that periodic examination to detect recurrent aneurysms may be indicated for such patients.
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Affiliation(s)
- K Tsutsumi
- Department of Neurosurgery, Aizu Chuou Hospital, Tokyo, Japan
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35
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Yeh L, Kwak S, Kim YS, Pedowitz R, Trudell D, Muhle C, Resnick D. Anterior labroligamentous structures of the glenohumeral joint: correlation of MR arthrography and anatomic dissection in cadavers. AJR Am J Roentgenol 1998; 171:1229-36. [PMID: 9798852 DOI: 10.2214/ajr.171.5.9798852] [Citation(s) in RCA: 50] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
OBJECTIVE The purpose of this study was to establish the accuracy of MR arthrography in depicting the morphology of the glenohumeral ligaments and the superior portion of the glenoid labrum. MATERIALS AND METHODS Findings on MR arthrography and those derived from careful dissection of gross specimens were compared in 15 cadaver shoulders, focusing on the morphology and size of the superior and middle glenohumeral ligaments and the morphology of the inferior glenohumeral ligament. The frequencies of sublabral recess and sublabral foramen seen on MR arthrography and at anatomic dissection were also compared. RESULTS For the superior and middle glenohumeral ligaments, moderate correlation of size was found between measurements made on MR arthrograms and at anatomic dissection, with the Spearman's rank correlation coefficient calculated as .69990 and .71133, respectively. Morphologic descriptions of the inferior glenohumeral ligament based on MR arthrography and on anatomic dissection also showed good association (Cohen's kappa = .8936). Dissection revealed that the sublabral recess was present in 11 specimens. Of these, 10 recesses were identified on MR arthrograms. MR arthrography also revealed a sublabral recess that was not found at dissection. Four sublabral foramina were identified by both MR arthrography and dissection, and two were revealed only by MR arthrography. CONCLUSION MR arthrography is useful in the evaluation of the glenohumeral ligaments and the superior portion of the labrum. Anatomic variations of these anterior intraarticular structures can be accurately shown by MR arthrography. In addition, estimation of the size of glenohumeral ligaments can be achieved with acceptable accuracy on MR arthrograms.
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Affiliation(s)
- L Yeh
- Department of Radiology, Veterans Affairs Medical Center and University of California, San Diego 92161, USA
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36
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Yeh LR, Kwak S, Kim YS, Chou DS, Muhle C, Skaf A, Trudell D, Resnick D. Evaluation of articular cartilage thickness of the humeral head and the glenoid fossa by MR arthrography: anatomic correlation in cadavers. Skeletal Radiol 1998; 27:500-4. [PMID: 9809879 DOI: 10.1007/s002560050427] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
OBJECTIVE To evaluate the accuracy of MR arthrography in determining the thickness of articular cartilage of the humeral head and glenoid fossa. DESIGN AND PATIENTS MR arthrography of the glenohumeral joint was performed in 17 cadaveric shoulders. Articular cartilage thickness was measured on the MR arthrographic images and corresponding anatomic sections. RESULTS The correlation coefficients for MR arthrographic measurement versus anatomic measurement of the cartilage thickness were 0.7324 and 0.8757 for humeral head and glenoid fossa, respectively. With regard to the humeral head, there was a tendency to overestimate regions of thin cartilage and underestimate regions of thick cartilage. This tendency was not found in the assessment of glenoid cartilage. The mean of the absolute value of MR-anatomic differences was similar on the glenoid side (0.27 mm) and the humeral side (0.29 mm). The accuracy of measurement was significantly better on the glenoid side (Fisher's r-to-Z transformation: Z=5.21, P=0.000001). CONCLUSION MR arthrography causes a moderate degree of error in the naked-eye measurement of the cartilage of the glenohumeral joint. The accuracy is higher on the glenoid side than on the humeral side.
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Affiliation(s)
- L R Yeh
- Department of Radiology, Veterans Affairs Medical Center, University of California San Diego, 92161, USA
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37
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Lee MY, Jensen E, Kwak S, Larson RA. Metastatic adenocarcinoma arising in a congenital foregut cyst of the esophagus: a case report with review of the literature. Am J Clin Oncol 1998; 21:64-6. [PMID: 9499261 DOI: 10.1097/00000421-199802000-00014] [Citation(s) in RCA: 43] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Benign tumors and cysts of the esophagus are rare, and malignant transformation of esophageal cysts is even more rare. In this article, we report on the first case to our knowledge of a patient presenting with metastatic adenocarcinoma arising in a congenital foregut cyst of the esophagus. A 37-year-old woman had multiple cysts along the aerodigestive tract and diffuse soft tissue metastases. Endoscopic biopsies of a mediastinal mass revealed an enteric cyst with a spectrum of columnar epithelium ranging from benign through adenomatous to frankly malignant. There was only transient response to radiotherapy and chemotherapy. Only three other cases of carcinoma arising from esophageal duplication foregut cysts have been reported, and none of these were metastatic. Given the rarity of malignant transformation within an esophageal cyst, prophylactic excision of known esophageal cysts is not warranted. However, biopsy of the cyst may be useful to exclude the possibility of malignancy, particularly if the onset of symptoms has been recent.
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Affiliation(s)
- M Y Lee
- Department of Medicine, Pritzker School of Medicine, University of Chicago, Illinois, USA
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38
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Hirata A, Nakamura R, Kwak S, Nagata N, Kamakura K. AMPA receptor-mediated slow neuronal death in the rat spinal cord induced by long-term blockade of glutamate transporters with THA. Brain Res 1997; 771:37-44. [PMID: 9383006 DOI: 10.1016/s0006-8993(97)00709-9] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Excitotoxicity secondary to the loss of glutamate transporters (GluT) has been proposed as a possible pathogenetic mechanism for neuronal degeneration in amyotrophic lateral sclerosis. We therefore investigated whether prolonged in vivo pharmacologic inhibition of GluT would result in neuronal damage in the rat. DL-Threo-beta-hydroxyaspartate (THA), a potent GluT inhibitor, and glutamate were continuously infused into the rat spinal subarachnoid space by using a mini-osmotic pump. Animals that received both THA and glutamate, but not those received either singly, displayed tail paralysis with or without hind-limb paralysis and urinary incontinence after the third postoperative day. Pathologically, symptomatic animals exhibited neuronal loss with a variable extent of gliosis preferentially involving the dorsal horn of the lumbosacral cord. In the rostral spinal segments adjacent to those regions of intense pathologic changes, small neurons in the dorsal horn were selectively destroyed, a pattern similar to the late-onset neuronal damage induced by continuous intrathecal administration of 1-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid (AMPA) [R. Nakamura et al., Brain Res. 654 (1994) 279-285]. These behavioral and pathologic changes were blocked by 6-cyano-7-nitroquinoxaline-2,3-dione (CNQX), suggesting that pharmacologic blockade of GluT causes selective neuronal damage in vivo by AMPA receptor activation.
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Affiliation(s)
- A Hirata
- Third Department of Internal Medicine, National Defense Medical College, Saitama, Japan
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39
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Nakamura R, Kamakura K, Hirata A, Kwak S. Concentration-dependent changes in motor behavior produced by continuous intrathecal infusion of excitatory amino acids in the rat spinal cord. Brain Res Brain Res Protoc 1997; 1:385-90. [PMID: 9384820 DOI: 10.1016/s1385-299x(97)00015-9] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
A growing body of evidence has suggested that glutamate receptors mediate selective degeneration of neurons in the central nervous system during the development of neurodegenerative diseases. Glutamate receptors are divided into N-methyl-D-aspartate (NMDA)-type and non-NMDA-type. Neurotoxicity mediated by the latter has attracted much interest as a possible causative mechanism underlying amyotrophic lateral sclerosis (ALS). As the clinical course of ALS is chronic and progressive, investigation of chronic effects of non-NMDA receptor agonists on neuronal function would be useful for evaluating the role of glutamate receptor-mediated neurotoxicity in ALS. However, chronic non-NMDA receptor-mediated neurotoxicity has been investigated less thoroughly than acute neurotoxicity. We infused an aqueous solution of R,S-alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionate (AMPA) intrathecally and continuously by an osmotic minipump in rats. This method of continuous infusion enabled us to keep the drug concentration relatively constant in the cerebrospinal fluid surrounding the spinal cord. The present method of AMPA administration is more suitable for investigating ALS pathogenesis than acute injections, in view of the gradual progression of the disease and the selectivity of lesions produced.
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Affiliation(s)
- R Nakamura
- Third Department of Internal Medicine, National Defense Medical College, Saitama, Japan
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40
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Nagao S, Kwak S, Kanazawa I. EAAT4, a glutamate transporter with properties of a chloride channel, is predominantly localized in Purkinje cell dendrites, and forms parasagittal compartments in rat cerebellum. Neuroscience 1997; 78:929-33. [PMID: 9174061 DOI: 10.1016/s0306-4522(97)00021-3] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Glutamate transporters play a pivotal role in terminating glutamatergic transmission by eliminating glutamate from the synaptic cleft. Four different glutamate transporter cDNAs have been isolated thus far, and their tissue distribution has been investigated using northern blot and immunohistochemical analysis. We raised site-directed antisera against a synthetic oligopeptide corresponding to the C-terminal of EAAT4, a recently cloned human glutamate transporter, and investigated the distribution of EAAT4 in rat cerebellum. Western blot analysis demonstrated that the affinity-purified antiserum SAE4 recognized specifically a single band (about 62 kDa) in the rat cerebellum, cerebrum and spinal cord. The SAE4-immunoreactivity was localized predominantly in the dendritic spines and distal dendrites of Purkinje cells. The intensity of the immunoreactivity was uneven among Purkinje cells, forming parasagittal compartments. Since EAAT4 also has the properties of a glutamate-gated chloride channel, it should be able to modulate the transmission at the parallel fiber-Purkinje cell synapses.
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Affiliation(s)
- S Nagao
- Department of Neurology, Institute for Brain Research, Faculty of Medicine, University of Tokyo, Bungkyo-ku, Japan
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41
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Abstract
A new surgical method for the treatment of chronic subdural haematoma is presented. A small craniostomy is made on the superior lateral angle of the forehead just beneath the hair line without hair removal using a high-speed drill. Through this aperture, evacuation and irrigation of the haematoma can be carried out safely. No infections occurred in a series of patients treated in this way, and the recurrence rate was 10% (2/20). The surgical wound was negligible. Because of its simplicity, and the lack of a need for hair removal, the procedure appears to be acceptable as an optional therapeutic modality.
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Affiliation(s)
- Y Yoshimoto
- Neurosurgical Institute, Higashi Yokohama Hospital, Kanagawa, Japan
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42
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Abstract
The demonstration of a genetic linkage between the copper-zinc superoxide dismutase (SOD1) gene and familial amyotrophic lateral sclerosis has aroused interest in the role of SOD1 in motoneuronal death. We investigated the expression of the human SOD1 gene at a cellular level in the motoneurons of patients with sporadic amyotrophic lateral sclerosis, patients with familial amyotrophic lateral sclerosis, and normal control subjects, using a quantitative in situ hybridization technique. There were no significant differences between the amounts of SOD1 messenger RNA observed in patients with sporadic disease, patients with familial disease, and normal control subjects. However, many of the atrophic motoneurons from patients with sporadic or familial disease had significantly lower levels of SOD1 messenger RNA, compared to morphologically intact motoneurons. Moreover, motoneurons in the normal spinal ventral horn and precentral motor cortex exhibited significantly higher levels of SOD1 messenger RNA than did other neurons. Our study indicated that vulnerable neurons in amyotrophic lateral sclerosis exhibit high levels of SOD1 messenger RNA, suggesting a close relationship between the SOD1 gene and the pathogenesis of amyotrophic lateral sclerosis.
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Affiliation(s)
- K Nishiyama
- Department of Neurology, School of Medicine, University of Tokyo, Bunkyo-ku, Japan
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43
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Kwak S. [Protection of excitotoxicity]. No To Shinkei 1996; 48:1077-85. [PMID: 8990475] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Affiliation(s)
- S Kwak
- Department of Neurology, Faculty of Medicine, University of Tokyo, Japan
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44
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Abstract
Two experiments explored the representation of the tonal hierarchy in Western music among older (aged 60 to 80) and younger (aged 15 to 22) musicians and nonmusicians. A probe tone technique was used: 4 notes from the major triad were presented, followed by 1 note chosen from the 12 notes of the chromatic scale. Whereas musicians had a better sense of the tonal hierarchy than nonmusicians, older adults were no worse than younger adults in differentiating the notes according to musical principles. However, older adults were more prone than younger adults to classify the notes by frequency proximity (pitch height) when proximity was made more salient, as were nonmusicians compared with musicians. With notes having ambiguous pitch height, pitch height effects disappeared among older adults but not nonmusicians. Older adults seem to have internalized tonal structure, but they sometimes fail to inhibit less musically relevant information.
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Affiliation(s)
- A R Halpern
- Department of Psychology, Bucknell University, Lewisburg, Pennsylvania 17837, USA.
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45
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Kwak S, Miyamoto M, Ishida M, Shinozaki H. Neurotoxicity of (2S,1'R,2'R,3'R)-2-(2,3-dicarboxycyclopropyl)glycine, a potent agonist for class II metabotropic glutamate receptors, in the rat. Neuroscience 1996; 73:687-95. [PMID: 8809790 DOI: 10.1016/0306-4522(96)00043-7] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Neurotoxicity of (2S,1'R,2'R,3'R)-2-(2,3-dicarboxycyclopropyl)glycine (DCG-IV), a potent agonist for metabotropic glutamate receptors negatively coupled to adenylyl cyclase, was investigated in vivo by the intraventricular administration in the rat, compared with that of (2S,1'S,2'S)-2-(carboxycyclopropyl)glycine (L-CCG-I) and (1S,3R)-1-aminocyclopentane-1,3-dicarboxylic acid [(1S,3R)-ACPD]. Neither L-CCG-I nor (1S,3R)-ACPD caused any apparent pathological change in the brain at an intraventricular dose of 1 mumol, whereas DCG-IV induced selective neuronal damage in some rats at higher doses than 3 nmol. The neurotoxicity was intensified in a dose-dependent manner, and at a dose of 50 nmol DCG-IV caused repetitive seizures and selective neuronal damage in all cases. Neuronal damage was pronounced in the cingulate cortex, lateral septum and hippocampus, and a few degenerating neurons were observed also in other brain areas, such as the striatum, thalamus or neocortex. Since DCG-IV activates N-methyl-D-aspartate-type receptors as well at relatively high concentrations, the protective effect of a competitive antagonist for N-methyl-D-aspartate receptors, 3-[(RS)-2-carboxypiperazin-4-yl]propyl-1-phosphonic acid (CPP), was examined on the neurotoxicity of DCG-IV. Although a combined treatment with CPP (0.1 nmol) completely blocked the neurotoxicity of N-methyl-D-aspartate (100 nmol), at least 3 nmol of CPP was necessary to decrease the neurotoxicity of DCG-IV (50 nmol) to a considerable extent. The synergistic activation of metabotropic glutamate receptors and N-methyl-D-aspartate receptors is suggested as a possible mechanism underlying the selective neuronal damage induced by DCG-IV, although a direct participation of metabotropic glutamate receptors in glutamate neurotoxicity is not deniable.
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Affiliation(s)
- S Kwak
- Department of Pharmacology, Tokyo Metropolitan Institute of Medical Science, Japan
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46
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Nishiyama K, Kwak S, Takekoshi S, Watanabe K, Kanazawa I. In situ nick end-labeling detects necrosis of hippocampal pyramidal cells induced by kainic acid. Neurosci Lett 1996; 212:139-42. [PMID: 8832658 DOI: 10.1016/0304-3940(96)12794-4] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
It is believed that in situ nick end-labeling (ISNEL) is an easy and selective method for detecting apoptosis in situ. To test whether ISNEL selectively detects apoptosis but not necrosis, we investigated the kainic acid (KA)-induced neuronal death with ISNEL, comparing with the results of gel electrophoresis and electron microscopy. Many degenerating neurons (ca. 50%) in the hippocampal CA1 area and amygdaloid complex were intensely stained with ISNEL 1-3 days after intraperitoneal injection of KA. Although most of the ISNEL-positive neurons displayed a pathological feature of necrosis, a small number of them displayed apoptosis-like changes when examined by electron microscopic observation. It should be noteworthy that ISNEL recognizes at least a certain form of necrosis and is not selective for apoptosis.
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Affiliation(s)
- K Nishiyama
- Department of Neurology, School of Medicine, University of Tokyo, Japan
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47
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Abstract
Two experiments explored the representation of the tonal hierarchy in Western music among older (aged 60 to 80) and younger (aged 15 to 22) musicians and nonmusicians. A probe tone technique was used: 4 notes from the major triad were presented, followed by 1 note chosen from the 12 notes of the chromatic scale. Whereas musicians had a better sense of the tonal hierarchy than nonmusicians, older adults were no worse than younger adults in differentiating the notes according to musical principles. However, older adults were more prone than younger adults to classify the notes by frequency proximity (pitch height) when proximity was made more salient, as were nonmusicians compared with musicians. With notes having ambiguous pitch height, pitch height effects disappeared among older adults but not nonmusicians. Older adults seem to have internalized tonal structure, but they sometimes fail to inhibit less musically relevant information.
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Affiliation(s)
- A R Halpern
- Department of Psychology, Bucknell University, Lewisburg, Pennsylvania 17837, USA.
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48
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Hanajima R, Terao Y, Ugawa Y, Kwak S, Kanazawa I. [Involuntary movements observed in a patient with Russian spring summer encephalitis]. Rinsho Shinkeigaku 1996; 36:571-6. [PMID: 8810852] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
A 38-year-old woman had an episode of headache, fever and convulsion in October, 1993. She became alert in two weeks, though weakness and atrophy remained in the upper limb muscles. She was diagnosed as Russian spring summer encephalitis (RSSE) based on several serological studies. Three kinds of involuntary movements were noted after recovery. These were spontaneous muscle jerks in the left arm, action tremor in the right arm and pathological associated-movement in the right leg. The movements were studied physiologically by electroencephalogram (EEG)-electromyogram (EMG) polygraphic recordings, jerk-locked averaging (JLA), magnetencephalography (MEG), and sensory evoked potentials (SEPs). The jerky movements in her left arm were observed at rest and aggravated by emotional stress. EEG-EMG polygraph showed that the jerks were sometimes associated with small spikes thus were considered to be due to epilepsia partialis continua (EPC). JLA analysis revealed a pre-myoclonus spike on the right hemisphere which preceded the onset of the jerk in the left first dorsal interosseous muscle by 25.2ms, which was equal to the magnetic cortical latency of that muscle. Jerk-locked magnetic field, obtained by averaging neuromagnetic activities with respect to the onset of myoclonus, showed that the spike preceding the jerk, originated from the right motor cortex. The spontaneous spikes were localized mainly on the right motor cortex. Sensory evoked potentials (SEPs) were normal in both size and latency. No hyperexcitability of the sensory cortex was demonstrated even by using paired stimulation SEPs. Based on these results, we conclude that the jerky movements in this patient were produced by abnormal spontaneous discharges in the motor cortex. The action tremor had a frequency of 4-5 Hz and its clinical features were compatible with cerebellar tremor. This is thought to result from a lesion in the left thalamus, affecting the cerebellothalamic pathways. Her right leg unintentionally moved whenever she began to move the hands. This was considered to be a pathological associated-movement due to dysfunction of the pyramidal tracts.
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Affiliation(s)
- R Hanajima
- Department of Neurology, School of Medicine, University of Tokyo
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49
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Abstract
We investigated the characteristics of the neurotoxicity mediated by non-N-methyl-D-aspartic acid (NMDA)-type glutamate receptors in the spinal cord by infusing rats intrathecally with three specific agonists (acromelic acid A (ACRO), kainic acid and 1-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid (AMPA)). When ACRO was infused intrathecally continuously for 2 h, the rats developed dose-dependent flaccid paraplegia during the infusion, followed by pure motor, rigid-spastic, long-lasting paraparesis (ED50: 220 pmol/h). The paraparetic rats showed selective degeneration of interneurons in the spinal cord with about 50% loss of their contents of glycine and aspartic and glutamic acids. The alpha-motoneurons in the ventral horns were largely free from permanent damage. These changes were selectively ameliorated by concomitant administration of 6-cyano-7-nitroquinoxaline-2,3-dione (CNQX), an antagonist at non-NMDA receptors. Kainate induced long-lasting paraplegia with neuronal damage at doses about 40-times higher than those of ACRO that caused paraplegia. When examined 30 days after kainate infusion, the neurotransmitter markers had decreased markedly in the lumbar cords of the rats with long-lasting paraplegia. Intrathecal infusion of large doses of AMPA caused long-lasting flaccid paraplegia, which were accompanied by extensive necrosis in the caudal spinal cord. It seems that ACRO exerts its unique pharmacological actions by activating a subclass of non-NMDA receptors distinct from those activated by kainate and AMPA, and may become a useful tool for investigating the biological roles of glutamate receptors.
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Affiliation(s)
- S Kwak
- Department of Neurology, University of Tokyo, Japan
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50
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Abstract
The factors contributing to neurological deterioration after early surgery for aneurysmal subarachnoid hemorrhage (SAH) were investigated. One hundred forty-two patients who underwent surgery within 3 days after SAH and recovered consciousness were divided into three age groups: 49 years of age or younger (Group A), 50 to 64 years old (Group B), and 65 years of age or older (Group C). Among these, 40 patients (28%) overall showed neurological deterioration; these cases were analyzed in detail. Although the highest incidence of deterioration was noted in patients in Group C (42%), angiographic vasospasm, quantified by measuring the change in the ratio of the diameters of the intracranial arteries to the extracranial internal carotid artery, was negatively correlated with age. In elderly patients, the severity of angiographic vasospasm was not related to the reversibility of symptoms or the outcome. At the time of aggravation, associated systemic complications such as cardiac decompensation, hypoxia, and electrolyte imbalance were noted in two (18%) of 11 patients in Group A, five (38%) of 13 in Group B, and eight (50%) of 16 in Group C, and these complications were significantly correlated with poor outcome in Group C. Although arterial narrowing is a leading cause of neurological deterioration after early aneurysmal surgery, the etiology is often multifactorial, especially in elderly patients, suggesting that hypervolemic therapy, which might provoke various complications, should be performed carefully under intensive monitoring.
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Affiliation(s)
- Y Yoshimoto
- Neurosurgical Institute of Higashi Yokohama Hospital, Kanagawa, Japan
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