1
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Asakura M, Higo T, Matsuo T, Uesugi R, Nishio-Hamane D, Nakatsuji S. Observation of Omnidirectional Exchange Bias at All Antiferromagnetic Polycrystalline Heterointerface. Adv Mater 2024:e2400301. [PMID: 38531113 DOI: 10.1002/adma.202400301] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/07/2024] [Revised: 03/13/2024] [Indexed: 03/28/2024]
Abstract
Due to promising functionalities that may dramatically enhance spintronics performance, antiferromagnets are the subject of intensive research for developing the next-generation active elements to replace ferromagnets. In particular, the recent experimental demonstration of the tunneling magnetoresistance and electrical switching using chiral antiferromagnets has sparked expectations for the practical integration of antiferromagnetic materials into device architectures. To further develop the technology to manipulate the magnetic anisotropies in all-antiferromagnetic devices, it is essential to realize exchange bias through the interface between antiferromagnetic multilayers. Here, we report our first observation on the omnidirectional exchange bias at an all-antiferromagnetic polycrystalline heterointerface. Our experiment demonstrates that the interfacial energy causing the exchange bias between the chiral-antiferromagnet Mn3Sn/collinear-antiferromagnet MnN layers is comparable to those found at the conventional ferromagnet/antiferromagnet interface at room temperature. In sharp contrast with previous reports using ferromagnets, the magnetic field control of the unidirectional anisotropy is found to be omnidirectional due to the absence of the shape anisotropy in the antiferromagnetic multilayer. The realization of the omnidirectional exchange bias at the interface between polycrystalline antiferromagnets on amorphous templates, highly compatible with existing Si-based devices, paves the way for developing ultra-low power and ultra-high speed memory devices based on antiferromagnets. This article is protected by copyright. All rights reserved.
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Affiliation(s)
- Mihiro Asakura
- Department of Physics, The University of Tokyo, Bunkyo-ku, Tokyo, 113-0033, Japan
| | - Tomoya Higo
- Department of Physics, The University of Tokyo, Bunkyo-ku, Tokyo, 113-0033, Japan
- Institute for Solid State Physics, The University of Tokyo, Kashiwa, Chiba, 277-8581, Japan
- CREST Japan Science and Technology Agency, Kawaguchi, Saitama, 332-0012, Japan
| | - Takumi Matsuo
- Department of Physics, The University of Tokyo, Bunkyo-ku, Tokyo, 113-0033, Japan
- Institute for Solid State Physics, The University of Tokyo, Kashiwa, Chiba, 277-8581, Japan
- Institute for Quantum Matter and Department of Physics and Astronomy, Johns Hopkins University, Baltimore, MD, 21218, USA
| | - Ryota Uesugi
- Institute for Solid State Physics, The University of Tokyo, Kashiwa, Chiba, 277-8581, Japan
| | - Daisuke Nishio-Hamane
- Institute for Solid State Physics, The University of Tokyo, Kashiwa, Chiba, 277-8581, Japan
| | - Satoru Nakatsuji
- Department of Physics, The University of Tokyo, Bunkyo-ku, Tokyo, 113-0033, Japan
- Institute for Solid State Physics, The University of Tokyo, Kashiwa, Chiba, 277-8581, Japan
- CREST Japan Science and Technology Agency, Kawaguchi, Saitama, 332-0012, Japan
- Institute for Quantum Matter and Department of Physics and Astronomy, Johns Hopkins University, Baltimore, MD, 21218, USA
- Trans-scale Quantum Science Institute, The University of Tokyo, Bunkyo-ku, Tokyo, 113-0033, Japan
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2
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Tanaka H, Higo T, Uesugi R, Yamagata K, Nakanishi Y, Machinaga H, Nakatsuji S. Roll-to-Roll Printing of Anomalous Nernst Thermopile for Direct Sensing of Perpendicular Heat Flux. Adv Mater 2023; 35:e2303416. [PMID: 37343181 DOI: 10.1002/adma.202303416] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/12/2023] [Revised: 06/12/2023] [Indexed: 06/23/2023]
Abstract
The anomalous Nernst effect (ANE) converts heat flux perpendicular to the plane into electricity, in sharp contrast with the Seebeck effect (SE), enabling mass production, large area, and flexibility of their devices through ordinary thin-film fabrication techniques. Heat flux sensors, one of the most promising applications of ANE, are powerful devices for evaluating heat flow and can lead to energy savings through efficient thermal management. In reality, however, SE caused by the in-plane heat flux is always superimposed on the measurement signal, making it difficult to evaluate the perpendicular heat flux. Here, ANE-type heat flux sensors that selectively detect a perpendicular heat flux are fabricated by adjusting the net Seebeck coefficient in their thermopile circuit with mass-producible roll-to-roll sputtering methods. The direct sensing of perpendicular heat flux using ANE-based flexible thermopiles, as well as their simple fabrication process, paves the way for the practical application of thin-film thermoelectric devices.
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Affiliation(s)
- Hirokazu Tanaka
- Laboratory for Magnetic and Electronic Properties at Interface, The University of Tokyo, 7-3-1 Bunkyo-ku, Tokyo, 113-0033, Japan
- Core Technology Research Center, Nitto Denko Corporation, 1-1-2 Ibaraki, Osaka, 567-8680, Japan
| | - Tomoya Higo
- Laboratory for Magnetic and Electronic Properties at Interface, The University of Tokyo, 7-3-1 Bunkyo-ku, Tokyo, 113-0033, Japan
- Department of Physics, The University of Tokyo, 7-3-1 Bunkyo-ku, Tokyo, 113-0033, Japan
- Institute for Solid State Physics, The University of Tokyo, 5-1-5 Kashiwa, Chiba, 277-8581, Japan
| | - Ryota Uesugi
- Institute for Solid State Physics, The University of Tokyo, 5-1-5 Kashiwa, Chiba, 277-8581, Japan
| | - Kazuto Yamagata
- Laboratory for Magnetic and Electronic Properties at Interface, The University of Tokyo, 7-3-1 Bunkyo-ku, Tokyo, 113-0033, Japan
- Core Technology Research Center, Nitto Denko Corporation, 1-1-2 Ibaraki, Osaka, 567-8680, Japan
| | - Yosuke Nakanishi
- Laboratory for Magnetic and Electronic Properties at Interface, The University of Tokyo, 7-3-1 Bunkyo-ku, Tokyo, 113-0033, Japan
- Core Technology Research Center, Nitto Denko Corporation, 1-1-2 Ibaraki, Osaka, 567-8680, Japan
| | - Hironobu Machinaga
- Laboratory for Magnetic and Electronic Properties at Interface, The University of Tokyo, 7-3-1 Bunkyo-ku, Tokyo, 113-0033, Japan
- Core Technology Research Center, Nitto Denko Corporation, 1-1-2 Ibaraki, Osaka, 567-8680, Japan
| | - Satoru Nakatsuji
- Laboratory for Magnetic and Electronic Properties at Interface, The University of Tokyo, 7-3-1 Bunkyo-ku, Tokyo, 113-0033, Japan
- Department of Physics, The University of Tokyo, 7-3-1 Bunkyo-ku, Tokyo, 113-0033, Japan
- Institute for Solid State Physics, The University of Tokyo, 5-1-5 Kashiwa, Chiba, 277-8581, Japan
- Trans-scale Quantum Science Institute, The University of Tokyo, 7-3-1 Bunkyo-ku, Tokyo, 113-0033, Japan
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3
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Matsuda T, Higo T, Koretsune T, Kanda N, Hirai Y, Peng H, Matsuo T, Yoshikawa N, Shimano R, Nakatsuji S, Matsunaga R. Ultrafast Dynamics of Intrinsic Anomalous Hall Effect in the Topological Antiferromagnet Mn_{3}Sn. Phys Rev Lett 2023; 130:126302. [PMID: 37027855 DOI: 10.1103/physrevlett.130.126302] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/02/2022] [Accepted: 02/06/2023] [Indexed: 06/19/2023]
Abstract
We investigate ultrafast dynamics of the anomalous Hall effect (AHE) in the topological antiferromagnet Mn_{3}Sn with sub-100 fs time resolution. Optical pulse excitations largely elevate the electron temperature up to 700 K, and terahertz probe pulses clearly resolve ultrafast suppression of the AHE before demagnetization. The result is well reproduced by microscopic calculation of the intrinsic Berry-curvature mechanism while the extrinsic contribution is clearly excluded. Our work opens a new avenue for the study of nonequilibrium AHE to identify the microscopic origin by drastic control of the electron temperature by light.
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Affiliation(s)
- Takuya Matsuda
- The Institute for Solid State Physics, The University of Tokyo, Kashiwa, Chiba 277-8581, Japan
| | - Tomoya Higo
- Department of Physics, The University of Tokyo, Bunkyo-ku, Tokyo, 113-0033, Japan
| | | | - Natsuki Kanda
- The Institute for Solid State Physics, The University of Tokyo, Kashiwa, Chiba 277-8581, Japan
| | - Yoshua Hirai
- Department of Physics, The University of Tokyo, Bunkyo-ku, Tokyo, 113-0033, Japan
| | - Hanyi Peng
- Department of Physics, The University of Tokyo, Bunkyo-ku, Tokyo, 113-0033, Japan
| | - Takumi Matsuo
- Department of Physics, The University of Tokyo, Bunkyo-ku, Tokyo, 113-0033, Japan
| | - Naotaka Yoshikawa
- Department of Physics, The University of Tokyo, Bunkyo-ku, Tokyo, 113-0033, Japan
| | - Ryo Shimano
- Department of Physics, The University of Tokyo, Bunkyo-ku, Tokyo, 113-0033, Japan
- Cryogenic Research Center, The University of Tokyo, Bunkyo-ku, Tokyo, 113-0032, Japan
| | - Satoru Nakatsuji
- The Institute for Solid State Physics, The University of Tokyo, Kashiwa, Chiba 277-8581, Japan
- Department of Physics, The University of Tokyo, Bunkyo-ku, Tokyo, 113-0033, Japan
- Trans-scale Quantum Science Institute, The University of Tokyo, Bunkyo-ku, Tokyo, 113-0033, Japan
- Institute for Quantum Matter and Department of Physics and Astronomy, Johns Hopkins University, Baltimore, 21218 Maryland, USA
| | - Ryusuke Matsunaga
- The Institute for Solid State Physics, The University of Tokyo, Kashiwa, Chiba 277-8581, Japan
- Trans-scale Quantum Science Institute, The University of Tokyo, Bunkyo-ku, Tokyo, 113-0033, Japan
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4
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Chen X, Higo T, Tanaka K, Nomoto T, Tsai H, Idzuchi H, Shiga M, Sakamoto S, Ando R, Kosaki H, Matsuo T, Nishio-Hamane D, Arita R, Miwa S, Nakatsuji S. Octupole-driven magnetoresistance in an antiferromagnetic tunnel junction. Nature 2023; 613:490-495. [PMID: 36653566 PMCID: PMC9849134 DOI: 10.1038/s41586-022-05463-w] [Citation(s) in RCA: 14] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2022] [Accepted: 10/19/2022] [Indexed: 01/19/2023]
Abstract
The tunnelling electric current passing through a magnetic tunnel junction (MTJ) is strongly dependent on the relative orientation of magnetizations in ferromagnetic electrodes sandwiching an insulating barrier, rendering efficient readout of spintronics devices1-5. Thus, tunnelling magnetoresistance (TMR) is considered to be proportional to spin polarization at the interface1 and, to date, has been studied primarily in ferromagnets. Here we report observation of TMR in an all-antiferromagnetic tunnel junction consisting of Mn3Sn/MgO/Mn3Sn (ref. 6). We measured a TMR ratio of around 2% at room temperature, which arises between the parallel and antiparallel configurations of the cluster magnetic octupoles in the chiral antiferromagnetic state. Moreover, we carried out measurements using a Fe/MgO/Mn3Sn MTJ and show that the sign and direction of anisotropic longitudinal spin-polarized current in the antiferromagnet7 can be controlled by octupole direction. Strikingly, the TMR ratio (about 2%) of the all-antiferromagnetic MTJ is much larger than that estimated using the observed spin polarization. Theoretically, we found that the chiral antiferromagnetic MTJ may produce a substantially large TMR ratio as a result of the time-reversal, symmetry-breaking polarization characteristic of cluster magnetic octupoles. Our work lays the foundation for the development of ultrafast and efficient spintronic devices using antiferromagnets8-10.
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Affiliation(s)
- Xianzhe Chen
- Department of Physics, University of Tokyo, Tokyo, Japan.,Institute for Solid State Physics, University of Tokyo, Chiba, Japan
| | - Tomoya Higo
- Department of Physics, University of Tokyo, Tokyo, Japan.,Institute for Solid State Physics, University of Tokyo, Chiba, Japan.,CREST, Japan Science and Technology Agency, Saitama, Japan
| | - Katsuhiro Tanaka
- Research Center for Advanced Science and Technology, University of Tokyo, Tokyo, Japan
| | - Takuya Nomoto
- Research Center for Advanced Science and Technology, University of Tokyo, Tokyo, Japan.,PRESTO, Japan Science and Technology Agency, Saitama, Japan
| | - Hanshen Tsai
- Department of Physics, University of Tokyo, Tokyo, Japan.,Institute for Solid State Physics, University of Tokyo, Chiba, Japan
| | - Hiroshi Idzuchi
- Department of Physics, University of Tokyo, Tokyo, Japan.,Institute for Solid State Physics, University of Tokyo, Chiba, Japan
| | - Masanobu Shiga
- Institute for Solid State Physics, University of Tokyo, Chiba, Japan
| | - Shoya Sakamoto
- Institute for Solid State Physics, University of Tokyo, Chiba, Japan
| | - Ryoya Ando
- Institute for Solid State Physics, University of Tokyo, Chiba, Japan
| | - Hidetoshi Kosaki
- Institute for Solid State Physics, University of Tokyo, Chiba, Japan
| | - Takumi Matsuo
- Department of Physics, University of Tokyo, Tokyo, Japan
| | | | - Ryotaro Arita
- CREST, Japan Science and Technology Agency, Saitama, Japan.,Research Center for Advanced Science and Technology, University of Tokyo, Tokyo, Japan.,RIKEN, Center for Emergent Matter Science, Saitama, Japan
| | - Shinji Miwa
- Institute for Solid State Physics, University of Tokyo, Chiba, Japan.,CREST, Japan Science and Technology Agency, Saitama, Japan.,Trans-scale Quantum Science Institute, University of Tokyo, Tokyo, Japan
| | - Satoru Nakatsuji
- Department of Physics, University of Tokyo, Tokyo, Japan. .,Institute for Solid State Physics, University of Tokyo, Chiba, Japan. .,CREST, Japan Science and Technology Agency, Saitama, Japan. .,Trans-scale Quantum Science Institute, University of Tokyo, Tokyo, Japan. .,Canadian Institute for Advanced Research, Toronto, Ontario, Canada.
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5
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Enzan N, Matsushima S, Ide T, Tohyama T, Funakoshi K, Higo T, Tsutsui H. The use of angiotensin receptor blockers is associated with greater recovery of cardiac function than angiotensin-converting-enzyme inhibitors among patients with dilated cardiomyopathy. Eur Heart J 2021. [DOI: 10.1093/eurheartj/ehab724.0782] [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: 11/14/2022] Open
Abstract
Abstract
Background
We previously showed that angiotensin-converting-enzyme inhibitors (ACEi) or angiotensin receptor blockers (ARB) were associated with heart failure with recovered ejection fraction (HFrecEF) in patients with dilated cardiomyopathy (DCM). However, the different effects of these drugs on cardiac reverse remodeling have not been fully elucidated. The aim of this study was to assess comparative effectiveness of ACEi versus ARB on recovery of left ventricular ejection fraction (LVEF) among patients with DCM.
Methods
We analyzed the clinical personal records of DCM, a national database of Japanese Ministry of Health, Labour and Welfare, from 2003 to 2014. Patients with LVEF <40% and on either ACEi or ARB were included. Eligible patients were divided into two groups according to the use of ACEi or ARB. A one-to-one propensity case-matched analysis was used. A propensity score was estimated by fitting a logistic-regression model which adjusted for age, sex, duration of HF, NYHA functional class (I-II vs. III-IV), systolic blood pressure, diastolic blood pressure, heart rate, atrial fibrillation, pacing, left bundle branch block, LVEF, hypertension, diabetes mellitus, hyperuricemia, chronic kidney disease, B-type natriuretic peptide (BNP), beta-blockers, mineralocorticoid receptor antagonists, loop diuretics, thiazides, digitalis, amiodarone, and oral inotropes. The primary outcome was defined as LVEF ≥40% at 3 years of follow-up.
Results
Out of 4,618 eligible patients, 2,238 patients received ACEi and 2,380 patients received ARB. Propensity score matching yielded 1,341 pairs. Mean age was 56.0 years and 2,041 (76.1%) was male. Mean LVEF was 27.6%, and median duration of HF was 1 year. The primary outcome was observed more frequently in ARB group than in ACEi group (59.8% vs. 54.1%; odds ratio [OR] 1.26; 95% confidence interval [CI] 1.08–1.47; P=0.003). The change in LVEF from baseline to 3 years of follow-up was greater in ARB group than in ACEi group (15.8±0.4 vs. 14.0±0.4%, P=0.002). In the ACEi group, 946 patients (70.6%) continued to receive ACEi at 3 years of follow-up, while 1,088 patients (81.3%) continued to receive ARB in the ARB group. Per-protocol analysis consistently showed that ARB increased the prevalence of HFrecEF (62.0% vs. 54.0%; OR 1.39; 95% CI 1.17–1.66; P<0.001). Subgroup analysis showed that ARB increased frequency of HFrecEF regardless systolic blood pressure, heart rate, LVEF, chronic kidney disease, and concomitant use of beta-blockers and mineralocorticoid receptor antagonists.
Conclusions
The use of ARB was associated with HFrecEF more frequently than ACEi among patients with DCM and reduced LVEF.
Funding Acknowledgement
Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Health Sciences Research Grants from the Japanese Ministry of Health, Labour and Welfare (Comprehensive Research on Cardiovascular Diseases)Japan Agency for Medical Research and Development (AMED) grant
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Affiliation(s)
- N Enzan
- Kyushu University, Department of Cardiovascular Medicine, Faculty of Medical Sciences, Fukuoka, Japan
| | - S Matsushima
- Kyushu University, Department of Cardiovascular Medicine, Faculty of Medical Sciences, Fukuoka, Japan
| | - T Ide
- Kyushu University, Department of Experimental and Clinical Cardiovascular Medicine, Graduate School of Medical Sciences, Fukuoka, Japan
| | - T Tohyama
- Kyushu University Hospital, Center for Clinical and Translational Research, Fukuoka, Japan
| | - K Funakoshi
- Kyushu University Hospital, Center for Clinical and Translational Research, Fukuoka, Japan
| | - T Higo
- Kyushu University Hospital, Department of Cardiovascular Medicine, Fukuoka, Japan
| | - H Tsutsui
- Kyushu University, Department of Cardiovascular Medicine, Faculty of Medical Sciences, Fukuoka, Japan
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6
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Miwa S, Iihama S, Nomoto T, Tomita T, Higo T, Ikhlas M, Sakamoto S, Otani Y, Mizukami S, Arita R, Nakatsuji S. Giant Effective Damping of Octupole Oscillation in an Antiferromagnetic Weyl Semimetal. Small Science 2021. [DOI: 10.1002/smsc.202000062] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Affiliation(s)
- Shinji Miwa
- The Institute for Solid State Physics The University of Tokyo Kashiwa Chiba 277-8581 Japan
- Trans-scale Quantum Science Institute The University of Tokyo Bunkyo Tokyo 113-0033 Japan
- CREST Japan Science and Technology Agency (JST) Kawaguchi Saitama 332-0012 Japan
| | - Satoshi Iihama
- CREST Japan Science and Technology Agency (JST) Kawaguchi Saitama 332-0012 Japan
- Frontier Research Institute for Interdisciplinary Sciences (FRIS) Tohoku University Sendai Miyagi 980-8578 Japan
- Advanced Institute for Materials Research (AIMR) Tohoku University Sendai Miyagi 980-8577 Japan
- Center for Spintronics Research Network (CSRN) Tohoku University Sendai Miyagi 980-8577 Japan
| | - Takuya Nomoto
- CREST Japan Science and Technology Agency (JST) Kawaguchi Saitama 332-0012 Japan
- Department of Applied Physics The University of Tokyo Tokyo 113-8656 Japan
| | - Takahiro Tomita
- The Institute for Solid State Physics The University of Tokyo Kashiwa Chiba 277-8581 Japan
- CREST Japan Science and Technology Agency (JST) Kawaguchi Saitama 332-0012 Japan
| | - Tomoya Higo
- CREST Japan Science and Technology Agency (JST) Kawaguchi Saitama 332-0012 Japan
- Department of Physics The University of Tokyo Tokyo 113-0033 Japan
| | - Muhammad Ikhlas
- The Institute for Solid State Physics The University of Tokyo Kashiwa Chiba 277-8581 Japan
| | - Shoya Sakamoto
- The Institute for Solid State Physics The University of Tokyo Kashiwa Chiba 277-8581 Japan
| | - YoshiChika Otani
- The Institute for Solid State Physics The University of Tokyo Kashiwa Chiba 277-8581 Japan
- Trans-scale Quantum Science Institute The University of Tokyo Bunkyo Tokyo 113-0033 Japan
- CREST Japan Science and Technology Agency (JST) Kawaguchi Saitama 332-0012 Japan
- RIKEN, Center for Emergent Matter Science (CEMS) Wako Saitama 351-0198 Japan
| | - Shigemi Mizukami
- Advanced Institute for Materials Research (AIMR) Tohoku University Sendai Miyagi 980-8577 Japan
- Center for Spintronics Research Network (CSRN) Tohoku University Sendai Miyagi 980-8577 Japan
- Center for Science and Innovation in Spintronics (CSIS) Tohoku University Sendai Miyagi 980-8577 Japan
| | - Ryotaro Arita
- CREST Japan Science and Technology Agency (JST) Kawaguchi Saitama 332-0012 Japan
- Department of Applied Physics The University of Tokyo Tokyo 113-8656 Japan
- RIKEN, Center for Emergent Matter Science (CEMS) Wako Saitama 351-0198 Japan
| | - Satoru Nakatsuji
- The Institute for Solid State Physics The University of Tokyo Kashiwa Chiba 277-8581 Japan
- Trans-scale Quantum Science Institute The University of Tokyo Bunkyo Tokyo 113-0033 Japan
- CREST Japan Science and Technology Agency (JST) Kawaguchi Saitama 332-0012 Japan
- Department of Physics The University of Tokyo Tokyo 113-0033 Japan
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7
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Tsai H, Higo T, Kondou K, Sakamoto S, Kobayashi A, Matsuo T, Miwa S, Otani Y, Nakatsuji S. Large Hall Signal due to Electrical Switching of an Antiferromagnetic Weyl Semimetal State. Small Science 2021. [DOI: 10.1002/smsc.202000025] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Affiliation(s)
- Hanshen Tsai
- Institute for Solid State Physics University of Tokyo Kashiwa Chiba 277-8581 Japan
- CREST Japan Science and Technology Agency Kawaguchi Saitama 332-0012 Japan
| | - Tomoya Higo
- Institute for Solid State Physics University of Tokyo Kashiwa Chiba 277-8581 Japan
- CREST Japan Science and Technology Agency Kawaguchi Saitama 332-0012 Japan
| | - Kouta Kondou
- Institute for Solid State Physics University of Tokyo Kashiwa Chiba 277-8581 Japan
- CREST Japan Science and Technology Agency Kawaguchi Saitama 332-0012 Japan
- RIKEN Center for Emergent Matter Science (CEMS) Wako Saitama 351-0198 Japan
| | - Shoya Sakamoto
- Institute for Solid State Physics University of Tokyo Kashiwa Chiba 277-8581 Japan
| | - Ayuko Kobayashi
- Institute for Solid State Physics University of Tokyo Kashiwa Chiba 277-8581 Japan
| | - Takumi Matsuo
- Institute for Solid State Physics University of Tokyo Kashiwa Chiba 277-8581 Japan
| | - Shinji Miwa
- Institute for Solid State Physics University of Tokyo Kashiwa Chiba 277-8581 Japan
- CREST Japan Science and Technology Agency Kawaguchi Saitama 332-0012 Japan
- Trans-scale Quantum Science Institute University of Tokyo Bunkyo-ku Tokyo 113-0033 Japan
| | - Yoshichika Otani
- Institute for Solid State Physics University of Tokyo Kashiwa Chiba 277-8581 Japan
- CREST Japan Science and Technology Agency Kawaguchi Saitama 332-0012 Japan
- RIKEN Center for Emergent Matter Science (CEMS) Wako Saitama 351-0198 Japan
- Trans-scale Quantum Science Institute University of Tokyo Bunkyo-ku Tokyo 113-0033 Japan
| | - Satoru Nakatsuji
- Institute for Solid State Physics University of Tokyo Kashiwa Chiba 277-8581 Japan
- CREST Japan Science and Technology Agency Kawaguchi Saitama 332-0012 Japan
- Trans-scale Quantum Science Institute University of Tokyo Bunkyo-ku Tokyo 113-0033 Japan
- Department of Physics University of Tokyo Bunkyo-ku Tokyo 113-0033 Japan
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8
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Valentine ME, Higo T, Nambu Y, Chaudhuri D, Wen J, Broholm C, Nakatsuji S, Drichko N. Impact of the Lattice on Magnetic Properties and Possible Spin Nematicity in the S=1 Triangular Antiferromagnet NiGa_{2}S_{4}. Phys Rev Lett 2020; 125:197201. [PMID: 33216581 DOI: 10.1103/physrevlett.125.197201] [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: 05/12/2020] [Accepted: 09/22/2020] [Indexed: 06/11/2023]
Abstract
NiGa_{2}S_{4} is a triangular lattice S=1 system with strong two dimensionality of the lattice, actively discussed as a candidate to host spin-nematic order brought about by strong quadrupole coupling. Using Raman scattering spectroscopy we identify a phonon of E_{g} symmetry which can modulate magnetic exchange J_{1} and produce quadrupole coupling. Additionally, our Raman scattering results demonstrate a loss of local inversion symmetry on cooling, which we associate with sulfur vacancies. This will lead to disordered Dzyaloshinskii-Moriya interactions, which can prevent long-range magnetic order. Using magnetic Raman scattering response we identify 160 K as a temperature of an upturn of magnetic correlations. The temperature range below 160 K, but above 50 K where antiferromagnetic correlations start to increase, is a candidate for spin-nematic regime.
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Affiliation(s)
- Michael E Valentine
- Institute for Quantum Matter and Department of Physics and Astronomy, Johns Hopkins University, Baltimore, Maryland 21218, USA
| | - Tomoya Higo
- Institute for Solid State Physics, University of Tokyo, Kashiwa, Chiba 277-8581, Japan
- CREST, Japan Science and Technology Agency, Kawaguchi, Saitama 332-0012, Japan
| | - Yusuke Nambu
- Institute for Solid State Physics, University of Tokyo, Kashiwa, Chiba 277-8581, Japan
- Institute for Materials Research, Tohoku University, Sendai, Miyagi 980-8577, Japan
| | - Dipanjan Chaudhuri
- Institute for Quantum Matter and Department of Physics and Astronomy, Johns Hopkins University, Baltimore, Maryland 21218, USA
| | - Jiajia Wen
- Institute for Quantum Matter and Department of Physics and Astronomy, Johns Hopkins University, Baltimore, Maryland 21218, USA
| | - Collin Broholm
- Institute for Quantum Matter and Department of Physics and Astronomy, Johns Hopkins University, Baltimore, Maryland 21218, USA
- NIST Center for Neutron Research, National Institute of Standards and Technology, Gaithersburg, Maryland 20899, USA
- Department of Materials Science and Engineering, Whiting School, Johns Hopkins University, Baltimore, Maryland 21218, USA
| | - Satoru Nakatsuji
- Institute for Quantum Matter and Department of Physics and Astronomy, Johns Hopkins University, Baltimore, Maryland 21218, USA
- Institute for Solid State Physics, University of Tokyo, Kashiwa, Chiba 277-8581, Japan
- CREST, Japan Science and Technology Agency, Kawaguchi, Saitama 332-0012, Japan
- Department of Physics, University of Tokyo, Bunkyo-ku, Tokyo 113-0033, Japan
- Trans-scale Quantum Science Institute, University of Tokyo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Natalia Drichko
- Institute for Quantum Matter and Department of Physics and Astronomy, Johns Hopkins University, Baltimore, Maryland 21218, USA
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9
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Enzan N, Matsushima S, Ide T, Kaku H, Tohyama T, Funakoshi K, Higo T, Tsutsui H. Use of direct oral anticoagulants is associated with better long-term outcomes in patients with atrial fibrillation and heart failure as compared with vitamin K antagonists. Eur Heart J 2020. [DOI: 10.1093/ehjci/ehaa946.1060] [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: 11/14/2022] Open
Abstract
Abstract
Background
Direct oral anticoagulants (DOACs) have been shown to be safe and effective in patients with atrial fibrillation (AF) as compared with warfarin, a vitamin K antagonist. However, the safety and efficacy of DOACs in patients with AF and heart failure (HF) have been unclear.
Purpose
The purpose of this study was to determine whether DOACs can improve long-term outcomes in patients with AF and HF as compared with warfarin.
Methods
We analyzed the JROADHF registry, which was a multicenter registry of patients hospitalized for the worsening HF in Japan. Baseline data were collected during the episode of index hospitalization from April 2013 to March 2014. Follow-up data were collected up to 4.5 years after the index hospitalization. Patients with AF and creatinine clearance ≥15 ml/min/1.73m2 were included. Valvular heart disease, congenital heart disease, and constrictive pericarditis were excluded. Eligible patients were divided into two groups according to the use of warfarin or DOACs. The primary outcome was defined as all-cause death. The secondary outcomes were defined as cardiovascular death, composite of all-cause death or cardiovascular hospitalization, and composite of stroke death or stroke related hospitalization. A one to one propensity case-matched analysis was used. Complete case analysis and multiple imputation analysis were also conducted as sensitivity analyses.
Results
Out of the 14,847 patients in this registry, 2,175 had AF, creatinine clearance ≥15 ml/min/1.73m2 and discharged alive. Propensity score matching yielded 475 pairs. In matching cohort, mean age was 76.5 years and 513 (54.0%) was male. Mean left ventricular ejection fraction was 48.6±16.4%. During a mean follow-up of 3.2 years, patients with DOACs had a lower incidence rate of all-cause death than those with warfarin (75.2 vs. 99.9 death per 1000 patient-years; rate ratio (RR) 0.75; 95% confidence interval [CI] 0.59–0.96; P=0.022). The incidence of cardiovascular death tended to be lower in DOAC group (30.9 vs. 43.1; incidence rate ratio 0.72; 95% CI 0.49–1.04; P=0.081). There were no significant differences in the incidence of composite of all cause death or cardiovascular hospitalization (252.3 vs. 269.4; RR 0.94; 95% CI 0.79–1.11; P=0.45) or composite of stroke death or stroke related hospitalization (13.1 vs. 16.7; RR 0.79; 95% CI 0.39–1.59; P=0.50). Cox regression model showed that DOAC was associated with lower mortality than warfarin (hazard ratio (HR) 0.75; 95% CI 0.59–0.96; P=0.023). Complete case analysis (HR 0.78; 95% CI 0.63–0.98; P=0.035) and multiple imputation analysis (HR 0.78; 95% CI 0.68–0.84; P<0.001) also showed the same results. A restricted cubic spline analysis demonstrated that the effectiveness of DOACs over warfarin waned with age, and DOACs were effective in patients younger than 80 years old.
Conclusion
Use of DOACs was associated with better long-term outcome in patients with HF as compared with warfarin.
Funding Acknowledgement
Type of funding source: Public grant(s) – National budget only. Main funding source(s): Japan Agency for Medical Research and Development
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Affiliation(s)
- N Enzan
- Kyushu University, Department of Cardiovascular Medicine, Faculty of Medical Sciences, Fukuoka, Japan
| | - S Matsushima
- Kyushu University Hospital, Department of Cardiovascular Medicine, Fukuoka, Japan
| | - T Ide
- Kyushu University, Department of Experimental and Clinical Cardiovascular Medicine, Graduate School of Medical Sciences, Fukuoka, Japan
| | - H Kaku
- Kyushu University, Department of Cardiovascular Medicine, Faculty of Medical Sciences, Fukuoka, Japan
| | - T Tohyama
- Kyushu University Hospital, Center for Clinical and Translational Research, Fukuoka, Japan
| | - K Funakoshi
- Kyushu University Hospital, Center for Clinical and Translational Research, Fukuoka, Japan
| | - T Higo
- Kyushu University, Department of Cardiovascular Medicine, Faculty of Medical Sciences, Fukuoka, Japan
| | - H Tsutsui
- Kyushu University, Department of Cardiovascular Medicine, Faculty of Medical Sciences, Fukuoka, Japan
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10
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Enzan N, Matsushima S, Ide T, Kaku H, Higo T, Tsutsui H. Beta-blocker use is associated with prevention of left ventricular remodeling in recovered dilated cardiomyopathy. Eur Heart J 2020. [DOI: 10.1093/ehjci/ehaa946.0911] [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
Withdrawal of optimal medical therapy has been reported to relapse cardiac dysfunction in patients with dilated cardiomyopathy (DCM) whose cardiac function had improved. However, it is unknown whether beta-blockers can prevent deterioration of cardiac function in those patients.
Purpose
We examined the effect of beta-blockers on left ventricular ejection fraction (LVEF) in recovered DCM.
Methods
We analyzed the clinical personal records of DCM, a national database of Japanese Ministry of Health, Labor and Welfare, between 2003 and 2014. Recovered DCM was defined as a previously documented LVEF <40% and a current LVEF ≥40%. Patients with recovered DCM were divided into two groups according to the use of beta-blockers. The primary outcome was defined as a decrease in LVEF >10% at two years of follow-up. A one to one propensity case-matched analysis was used. A per-protocol analysis was also performed. Considering intra- and inter-observer variability of echocardiographic evaluations, we also examined outcomes by multivariable logistic regression model after changing the inclusion criteria as follows; (1) previous LVEF <40% and current LVEF ≥40%; (2) previous LVEF <35% and current LVEF ≥40%; (3) previous LVEF <30% and current LVEF ≥40%; (4) previous LVEF <40% and current LVEF ≥50%. Outcomes were also changed as (1) decrease in LVEF ≥5% (2) decrease in LVEF ≥10% (3) decrease in LVEF ≥15%. The analysis of outcomes by using combination of multiple imputation and inverse probability of treatment weighting was also conducted to assess the effects of missing data and selection bias attributable to propensity score matching on outcomes.
Results
From 2003 to 2014, 40,794 consecutive patients with DCM were screened. Out of 5,338 eligible patients, 4,078 received beta-blockers. Propensity score matching yielded 998 pairs. Mean age was 61.7 years and 1,497 (75.0%) was male. Mean LVEF was 49.1±8.1%. The primary outcome was observed less frequently in beta-blocker group than in no beta-blocker group (18.0% vs. 23.5%; odds ratio [OR] 0.72; 95% confidence interval [CI] 0.58–0.89; P=0.003). The prevalence of increases in LVDd (11.5% vs. 15.8%; OR 0.70; 95% CI 0.54–0.91; P=0.007) and LVDs (23.1% vs. 27.2%; OR 0.80; 95% CI 0.65–0.99; P=0.041) was also lower in the beta-blocker group. Similar results were obtained in per-protocol analysis. These results were robust to several sensitivity analyses. As a result of preventing a decrease in LVEF, the deterioration to HFrEF was also prevented by the use of beta-blocker (23.6% vs. 30.6%). Subgroup analysis demonstrated that beta-blocker prevented decrease in LVEF regardless of atrial fibrillation.
Conclusion
Use of beta-blocker was associated with prevention of decrease in left ventricular ejection fraction in patients with recovered DCM.
Funding Acknowledgement
Type of funding source: Public grant(s) – National budget only. Main funding source(s): Health Sciences Research Grants from the Japanese Ministry of Health, Labour and Welfare (Comprehensive Research on Cardiovascular Diseases)
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Affiliation(s)
- N Enzan
- Kyushu University, Department of Cardiovascular Medicine, Faculty of Medical Sciences, Fukuoka, Japan
| | - S Matsushima
- Kyushu University Hospital, Department of Cardiovascular Medicine, Fukuoka, Japan
| | - T Ide
- Kyushu University, Department of Experimental and Clinical Cardiovascular Medicine, Graduate School of Medical Sciences, Fukuoka, Japan
| | - H Kaku
- Kyushu University, Department of Cardiovascular Medicine, Faculty of Medical Sciences, Fukuoka, Japan
| | - T Higo
- Kyushu University Hospital, Department of Cardiovascular Medicine, Fukuoka, Japan
| | - H Tsutsui
- Kyushu University, Department of Cardiovascular Medicine, Faculty of Medical Sciences, Fukuoka, Japan
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11
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Sakai A, Minami S, Koretsune T, Chen T, Higo T, Wang Y, Nomoto T, Hirayama M, Miwa S, Nishio-Hamane D, Ishii F, Arita R, Nakatsuji S. Iron-based binary ferromagnets for transverse thermoelectric conversion. Nature 2020; 581:53-57. [DOI: 10.1038/s41586-020-2230-z] [Citation(s) in RCA: 87] [Impact Index Per Article: 21.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2019] [Accepted: 02/04/2020] [Indexed: 11/09/2022]
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12
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Matsuda T, Kanda N, Higo T, Armitage NP, Nakatsuji S, Matsunaga R. Room-temperature terahertz anomalous Hall effect in Weyl antiferromagnet Mn 3Sn thin films. Nat Commun 2020; 11:909. [PMID: 32060261 PMCID: PMC7021706 DOI: 10.1038/s41467-020-14690-6] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2019] [Accepted: 01/24/2020] [Indexed: 12/03/2022] Open
Abstract
Antiferromagnetic spin motion at terahertz (THz) frequencies attracts growing interests for fast spintronics, however, their smaller responses to external field inhibit device application. Recently the noncollinear antiferromagnet Mn3Sn, a Weyl semimetal candidate, was reported to show large anomalous Hall effect (AHE) at room temperature comparable to ferromagnets. Dynamical aspect of such large responses is an important issue to be clarified for future THz data processing. Here the THz anomalous Hall conductivity in Mn3Sn thin films is investigated by polarization-resolved spectroscopy. Large anomalous Hall conductivity \documentclass[12pt]{minimal}
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\begin{document}$${\mathrm{Re}}\;\sigma _{xy}\left( \omega \right) \sim 20\;{\mathrm{\Omega }}^{ - 1}{\mathrm{cm}}^{ - 1}$$\end{document}Reσxyω~20Ω−1cm−1 at THz frequencies is clearly observed as polarization rotation. A peculiar temperature dependence corresponding to the breaking/recovery of symmetry in the spin texture is also discussed. Observation of the THz AHE at room temperature demonstrates the ultrafast readout for the antiferromagnetic spintronics using Mn3Sn, and will also open new avenue for studying nonequilibrium dynamics in Weyl antiferromagnets. Antiferromagnets promise great potential for spintronic applications due to their spin excitations at terahertz frequencies, however, read out of the spin state is hindered by the small response to external fields. Here the authors demonstrate all optical readout of the spin state of antiferromagnetic Mn3Sn at THz frequency.
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Affiliation(s)
- Takuya Matsuda
- The Institute for Solid State Physics, The University of Tokyo, Kashiwa, Chiba, 277-8581, Japan
| | - Natsuki Kanda
- The Institute for Solid State Physics, The University of Tokyo, Kashiwa, Chiba, 277-8581, Japan
| | - Tomoya Higo
- The Institute for Solid State Physics, The University of Tokyo, Kashiwa, Chiba, 277-8581, Japan.,CREST, Japan Science and Technology Agency, Kawaguchi, Saitama, 332-0012, Japan
| | - N P Armitage
- The Institute of Quantum Matter, Department of Physics and Astronomy, The Johns Hopkins University, Baltimore, MA, 21218, USA
| | - Satoru Nakatsuji
- The Institute for Solid State Physics, The University of Tokyo, Kashiwa, Chiba, 277-8581, Japan.,CREST, Japan Science and Technology Agency, Kawaguchi, Saitama, 332-0012, Japan.,The Institute of Quantum Matter, Department of Physics and Astronomy, The Johns Hopkins University, Baltimore, MA, 21218, USA.,Department of Physics, The University of Tokyo, Hongo, Bunkyo-Ku, Tokyo, 113-0033, Japan
| | - Ryusuke Matsunaga
- The Institute for Solid State Physics, The University of Tokyo, Kashiwa, Chiba, 277-8581, Japan. .,PRESTO, Japan Science and Technology Agency, 4-1-8 Honcho, Kawaguchi, Saitama, 332-0012, Japan.
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13
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Higo T, Man H, Gopman DB, Wu L, Koretsune T, van ’t Erve OMJ, Kabanov YP, Rees D, Li Y, Suzuki MT, Patankar S, Ikhlas M, Chien CL, Arita R, Shull RD, Orenstein J, Nakatsuji S. Large magneto-optical Kerr effect and imaging of magnetic octupole domains in an antiferromagnetic metal. Nat Photonics 2018; 12:73-78. [PMID: 29910828 PMCID: PMC5997294 DOI: 10.1038/s41566-017-0086-z] [Citation(s) in RCA: 63] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/29/2017] [Accepted: 12/13/2017] [Indexed: 05/15/2023]
Abstract
When a polarized light beam is incident upon the surface of a magnetic material, the reflected light undergoes a polarization rotation1. This magneto-optical Kerr effect (MOKE) has been intensively studied in a variety of ferro- and ferrimagnetic materials because it provides a powerful probe for electronic and magnetic properties2, 3 as well as for various applications including magneto-optical recording4. Recently, there has been a surge of interest in antiferromagnets (AFMs) as prospective spintronic materials for high-density and ultrafast memory devices, owing to their vanishingly small stray field and orders of magnitude faster spin dynamics compared to their ferromagnetic counterparts5-9. In fact, the MOKE has proven useful for the study and application of the antiferromagnetic (AF) state. Although limited to insulators, certain types of AFMs are known to exhibit a large MOKE, as they are weak ferromagnets due to canting of the otherwise collinear spin structure10-14. Here we report the first observation of a large MOKE signal in an AF metal at room temperature. In particular, we find that despite a vanishingly small magnetization of M ~0.002 µB/Mn, the non-collinear AF metal Mn3Sn15 exhibits a large zero-field MOKE with a polar Kerr rotation angle of 20 milli-degrees, comparable to ferromagnetic metals. Our first-principles calculations have clarified that ferroic ordering of magnetic octupoles in the non-collinear Néel state16 may cause a large MOKE even in its fully compensated AF state without spin magnetization. This large MOKE further allows imaging of the magnetic octupole domains and their reversal induced by magnetic field. The observation of a large MOKE in an AF metal should open new avenues for the study of domain dynamics as well as spintronics using AFMs.
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Affiliation(s)
- Tomoya Higo
- Institute for Solid State Physics, University of Tokyo, Kashiwa, Chiba 277-8581, Japan
- CREST, Japan Science and Technology Agency, Kawaguchi, Saitama 332-0012, Japan
| | - Huiyuan Man
- Institute for Solid State Physics, University of Tokyo, Kashiwa, Chiba 277-8581, Japan
| | - Daniel B. Gopman
- Materials Science and Engineering Division, National Institute of Standards and Technology, Gaithersburg, MD 20899, USA
| | - Liang Wu
- Department of Physics, University of California, Berkeley, California 94720, USA
- Materials Science Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
- Department of Physics and Astronomy, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA
| | - Takashi Koretsune
- CREST, Japan Science and Technology Agency, Kawaguchi, Saitama 332-0012, Japan
- Department of Physics, Tohoku University, Sendai, Miyagi 980-8578, Japan
- RIKEN-CEMS, Wako, Saitama 351-0198, Japan
| | - Olaf M. J. van ’t Erve
- Materials Science and Technology Division, U.S. Naval Research Laboratory, Washington, DC 20375, USA
| | - Yury P. Kabanov
- Materials Science and Engineering Division, National Institute of Standards and Technology, Gaithersburg, MD 20899, USA
- Institute of Solid State Physics, Russian Academy of Sciences, Chernogolovka, Moscow Region 142432, Russia
| | - Dylan Rees
- Department of Physics, University of California, Berkeley, California 94720, USA
- Materials Science Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
| | - Yufan Li
- Department of Physics and Astronomy, Johns Hopkins University, Baltimore, MD 21218, USA
| | - Michi-To Suzuki
- CREST, Japan Science and Technology Agency, Kawaguchi, Saitama 332-0012, Japan
- RIKEN-CEMS, Wako, Saitama 351-0198, Japan
| | - Shreyas Patankar
- Department of Physics, University of California, Berkeley, California 94720, USA
- Materials Science Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
| | - Muhammad Ikhlas
- Institute for Solid State Physics, University of Tokyo, Kashiwa, Chiba 277-8581, Japan
- CREST, Japan Science and Technology Agency, Kawaguchi, Saitama 332-0012, Japan
| | - C. L. Chien
- Department of Physics and Astronomy, Johns Hopkins University, Baltimore, MD 21218, USA
| | - Ryotaro Arita
- CREST, Japan Science and Technology Agency, Kawaguchi, Saitama 332-0012, Japan
- RIKEN-CEMS, Wako, Saitama 351-0198, Japan
| | - Robert D. Shull
- Materials Science and Engineering Division, National Institute of Standards and Technology, Gaithersburg, MD 20899, USA
| | - Joseph Orenstein
- Department of Physics, University of California, Berkeley, California 94720, USA
- Materials Science Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
| | - Satoru Nakatsuji
- Institute for Solid State Physics, University of Tokyo, Kashiwa, Chiba 277-8581, Japan
- CREST, Japan Science and Technology Agency, Kawaguchi, Saitama 332-0012, Japan
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14
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Higo T, Aramaki S, Yasunaga T. PB-11Molecular Mechanism of Actin Cytoskeleton Repair In Nerve Cell Elucidated by Light and Electron Microscopy. Microscopy (Oxf) 2017. [DOI: 10.1093/jmicro/dfx112] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Affiliation(s)
- Tomoya Higo
- Department of Creative Informatics, Kyushu Institute of Technology, Fukuoka, Japan,
| | | | - Takuo Yasunaga
- Department of Bioscience and Bioinformatics, Faculty of Computer Science and Systems Engineering, Kyushu Institute of Technology, Fukuoka, Japan
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15
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Yasunaga T, Aramaki S, Higo T. 2S-A1-2Cell Architecture Elucidated by Three-dimensional Cryo-electron Microscopy. Microscopy (Oxf) 2017. [DOI: 10.1093/jmicro/dfx050] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Affiliation(s)
- Takuo Yasunaga
- Dept. of Biosci. and Bioinfo., School of Comp. Sci. and Sys. Eng., Kyushu Institute of Technology, Fukuoka, Japan, and
- ABiS, Japan
| | - Shinji Aramaki
- Dept. of Biosci. and Bioinfo., School of Comp. Sci. and Sys. Eng., Kyushu Institute of Technology, Fukuoka, Japan, and
| | - Tomoya Higo
- Dept. of Biosci. and Bioinfo., School of Comp. Sci. and Sys. Eng., Kyushu Institute of Technology, Fukuoka, Japan, and
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16
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17
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Nakatsuji S, Kiyohara N, Higo T. Large anomalous Hall effect in a non-collinear antiferromagnet at room temperature. Nature 2015; 527:212-5. [PMID: 26524519 DOI: 10.1038/nature15723] [Citation(s) in RCA: 224] [Impact Index Per Article: 24.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2015] [Accepted: 09/01/2015] [Indexed: 11/09/2022]
Abstract
In ferromagnetic conductors, an electric current may induce a transverse voltage drop in zero applied magnetic field: this anomalous Hall effect is observed to be proportional to magnetization, and thus is not usually seen in antiferromagnets in zero field. Recent developments in theory and experiment have provided a framework for understanding the anomalous Hall effect using Berry-phase concepts, and this perspective has led to predictions that, under certain conditions, a large anomalous Hall effect may appear in spin liquids and antiferromagnets without net spin magnetization. Although such a spontaneous Hall effect has now been observed in a spin liquid state, a zero-field anomalous Hall effect has hitherto not been reported for antiferromagnets. Here we report empirical evidence for a large anomalous Hall effect in an antiferromagnet that has vanishingly small magnetization. In particular, we find that Mn3Sn, an antiferromagnet that has a non-collinear 120-degree spin order, exhibits a large anomalous Hall conductivity of around 20 per ohm per centimetre at room temperature and more than 100 per ohm per centimetre at low temperatures, reaching the same order of magnitude as in ferromagnetic metals. Notably, the chiral antiferromagnetic state has a very weak and soft ferromagnetic moment of about 0.002 Bohr magnetons per Mn atom (refs 10, 12), allowing us to switch the sign of the Hall effect with a small magnetic field of around a few hundred oersted. This soft response of the large anomalous Hall effect could be useful for various applications including spintronics--for example, to develop a memory device that produces almost no perturbing stray fields.
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Affiliation(s)
- Satoru Nakatsuji
- Institute for Solid State Physics, University of Tokyo, Kashiwa 277-8581, Japan.,PRESTO, Japan Science and Technology Agency (JST), 4-1-8 Honcho Kawaguchi, Saitama 332-0012, Japan
| | - Naoki Kiyohara
- Institute for Solid State Physics, University of Tokyo, Kashiwa 277-8581, Japan
| | - Tomoya Higo
- Institute for Solid State Physics, University of Tokyo, Kashiwa 277-8581, Japan
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18
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Koshinuma S, Inoue Y, Yamada S, Takamori S, Shibutani A, Adachi T, Murakami T, Higo T, Yokoe Y, Yamamoto G. A case of obstructive sleep apnea syndrome caused by a huge epidermoid cyst. Int J Oral Maxillofac Surg 2015. [DOI: 10.1016/j.ijom.2015.08.646] [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: 11/17/2022]
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19
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Koshinuma S, Yamamoto A, Kagawa T, Kosasa Y, Shibutani A, Murakami T, Kurimoto N, Higo T, Yamada N, Yamamoto G. Treatment of bilateral, residual temporomandibular joint dislocation in a schizophrenic patient. Int J Oral Maxillofac Surg 2015. [DOI: 10.1016/j.ijom.2015.08.200] [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: 11/24/2022]
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20
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Fujita K, Makimoto K, Higo T, Shigematsu M, Hotokebuchi T. Changes in the WOMAC, EuroQol and Japanese lifestyle measurements among patients undergoing total hip arthroplasty. Osteoarthritis Cartilage 2009; 17:848-55. [PMID: 19147375 DOI: 10.1016/j.joca.2008.11.012] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.5] [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] [Received: 02/27/2008] [Accepted: 11/16/2008] [Indexed: 02/02/2023]
Abstract
OBJECTIVE To assess changes in the health outcomes of Japanese patients before and after total hip arthroplasty (THA), and to assess the impact of THA on commonly performed postures or body positions requiring deep flexion of the hip joint such as the use of Japanese squat toilets. METHODS Consecutive patients undergoing primary THA between July 2003 and July 2004 were eligible for the study. The Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) and the EuroQol 5D (EQ-5D) were administered at the preoperative period and two postoperative periods of 6 weeks and 6 months. The patients were also asked to rate three items regarding common activities of daily living in Japan such as squatting. Changes in scores were examined using effect size and proportion at the floor and ceiling. RESULTS Four-hundred and fifty-one patients completed both pre- and post-THA surveys. Significant improvements in pain and physical function as measured by WOMAC and EQ-5D were evident within 6 weeks. Changes in WOMAC and EQ-5D subscale scores and scores for each item from the three time periods were highly significant (P=0.000). The effect size was 1.56 for WOMAC pain and 1.38 for physical function at 6 months. In contrast, two items (Japanese toilet and seiza) became significantly worse at the 6-week postoperative period (P=0.000) and returned to preoperative levels by the 6-month postoperative period. CONCLUSION These results highlight the importance of evaluating culturally sensitive physical functions in addition to conventional measurements for the health outcomes of THA patients.
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Affiliation(s)
- K Fujita
- Division of Nursing, Faculty of Medicine, Saga University, Saga, Japan.
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21
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Higo T, Mukaisho K, Ling ZQ, Oue K, Chen KH, Araki Y, Sugihara H, Yamamoto G, Hattori T. An animal model of intrinsic dental erosion caused by gastro-oesophageal reflux disease. Oral Dis 2009; 15:360-5. [PMID: 19371399 DOI: 10.1111/j.1601-0825.2009.01561.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
OBJECTIVES To explore the association between dental erosion and gastro-oesophageal reflux disease (GORD), we used an animal model of GORD. MATERIALS AND METHODS We performed an operation to force gastro-duodenal contents reflux in male Wistar rats, and examined the teeth in the reflux rats at 15 or 30 weeks postoperatively. Dental erosion was evaluated based on a slightly modified index from a previous report. Estimation of pH was employed in the oesophageal and gastric contents. RESULTS Macroscopically, dental erosion was only detected in the reflux rats. Histopathologically, dentin exposure was detected in three of the seven cases after 30 weeks. Alveolar bone destruction and osteomyelitis were also noted in severe cases. The pH of the oesophageal and stomach contents was 6.93 +/- 0.15 and 3.7 +/- 0.39, respectively. CONCLUSIONS We confirmed the relationship between dental erosion and GORD. First step of dental erosion caused by GORD is the loss of surface enamel induced by regurgitation of an acidic liquid and acidic gas. Subsequently, further destruction of dental hard tissues and tooth supporting structure is accelerated by mixed juice with gastric and duodenal contents. The reflux animal model is a useful tool to examine the mechanism of dental erosion in GORD.
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Affiliation(s)
- T Higo
- Department of Pathology, Shiga University of Medical Science, Otsu, Shiga, Japan
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Abstract
OBJECTIVE Curcumin and quercetin are antioxidant molecules with anti-proliferative, anti-inflammatory and immunosuppressive activities. The objective of this study was to investigate the inhibitory activity of these agents using four assays of inflammatory aspects of arthritis. METHODS Crystal-induced neutrophil activation was measured by luminol-dependent chemiluminescence. Synoviocyte proliferation was measured by an MTS assay using HIG-82 rabbit synoviocytes in cell culture. Chondrocyte (cultured primary cells) expression of the matrix metalloproteinases collagenase and stromelysin was measured by Northern Blot analysis. Angiogenesis was measured using the chorioallantoic membrane of the chick embryo. RESULTS Both agents inhibited neutrophil activation, synoviocyte proliferation and angiogenesis. Curcumin strongly inhibited collagenase and stromelysin expression at micromolar concentrations whereas quercetin had no effect in this assay. CONCLUSION These studies suggest that curcumin and to a lesser extent quercetin may offer therapeutic potential for the treatment of crystal-induced arthritis or rheumatoid arthritis.
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Affiliation(s)
- J K Jackson
- Faculty of Pharmaceutical Sciences, University of British Columbia, 2146 East Mall, Vancouver BC, Canada V6T 1Z3
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23
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Mawatari M, Higo T, Tsutsumi Y, Shigematsu M, Hotokebuchi T. Effectiveness of autologous fibrin tissue adhesive in reducing postoperative blood loss during total hip arthroplasty: a prospective randomised study of 100 cases. J Orthop Surg (Hong Kong) 2006; 14:117-21. [PMID: 16914772 DOI: 10.1177/230949900601400202] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.3] [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: 12/22/2022] Open
Abstract
PURPOSE To evaluate the effectiveness of autologous fibrin tissue adhesive (auto-FTA) in reducing blood loss during cementless total hip arthroplasty (THA). METHODS From September 2000 to August 2001, 100 patients who predonated 400 ml of autologous blood were randomised to undergo either standard treatment with auto-FTA (auto-FTA group) or standard treatment alone (control group). The volume of postoperative blood loss and the decrease in haemoglobin level were measured. All patients were followed up for 3 years to evaluate the rate of bone ingrowth and heterotopic ossification. RESULTS The mean postoperative blood loss was 580 ml (standard deviation [SD], 240 ml) in the auto-FTA group and 810 ml (SD, 341 ml) in the control group; the difference was significant (230 ml, p<0.001). The decrease in haemoglobin concentration was 17 g/l (SD, 11 g/l) in the auto-FTA group and 22 g/l (SD, 12 g/l) in the control group. The difference was significant (5 g/l, p=0.03). The percentage of total blood loss of >1200 ml in any single patient was significantly lower in the auto-FTA group (4%) than in the control group (20%) [p=0.01]. CONCLUSION Auto-FTA is a safe and effective means of reducing perioperative blood loss in THA.
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Affiliation(s)
- M Mawatari
- Department of Orthopaedic Surgery, Saga University, Saga-City, Japan.
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Honda Y, Kubo K, Anderson S, Araki S, Bane K, Brachmann A, Frisch J, Fukuda M, Hasegawa K, Hayano H, Hendrickson L, Higashi Y, Higo T, Hirano K, Hirose T, Iida K, Imai T, Inoue Y, Karataev P, Kuriki M, Kuroda R, Kuroda S, Luo X, McCormick D, Matsuda M, Muto T, Nakajima K, Naito T, Nelson J, Nomura M, Ohashi A, Omori T, Okugi T, Ross M, Sakai H, Sakai I, Sasao N, Smith S, Suzuki T, Takano M, Taniguchi T, Terunuma N, Turner J, Toge N, Urakawa J, Vogel V, Woodley M, Wolski A, Yamazaki I, Yamazaki Y, Yocky G, Young A, Zimmermann F. Achievement of ultralow emittance beam in the accelerator test facility damping ring. Phys Rev Lett 2004; 92:054802. [PMID: 14995314 DOI: 10.1103/physrevlett.92.054802] [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: 08/05/2003] [Indexed: 05/24/2023]
Abstract
For high luminosity in electron-positron linear colliders, it is essential to generate low vertical emittance beams. We report on the smallest vertical emittance achieved in single-bunch-mode operation of the Accelerator Test Facility, which satisfies the requirement of the x-band linear collider. The emittances were measured with a laser-wire beam-profile monitor installed in the damping ring. The bunch length and the momentum spread of the beam were also recorded under the same conditions. The smallest vertical rms emittance measured at low intensity is 4 pm at a beam energy of 1.3 GeV, which corresponds to the normalized emittance of 1.0x1.0(-8) m. It increases by a factor of 1.5 for a bunch intensity of 10(10) electrons. The measured data agreed to the calculation of intrabeam scattering within much better than a factor of 2.
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Affiliation(s)
- Y Honda
- Department of Physics, Kyoto University, Kyoto, Japan
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25
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Kubo K, Akemoto M, Anderson S, Aoki T, Araki S, Bane KLF, Blum P, Corlett J, Dobashi K, Emma P, Frisch J, Fukuda M, Guo Z, Hasegawa K, Hayano H, Higo T, Higurashi A, Honda Y, Iimura T, Imai T, Jobe K, Kamada S, Karataev P, Kashiwagi S, Kim E, Kobuki T, Kotseroglou T, Kurihara Y, Kuriki M, Kuroda R, Kuroda S, Lee T, Luo X, McCormick DJ, McKee B, Mimashi T, Minty M, Muto T, Naito T, Naumenko G, Nelson J, Nguyen MN, Oide K, Okugi T, Omori T, Oshima T, Pei G, Potylitsyn A, Qin Q, Raubenheimer T, Ross M, Sakai H, Sakai I, Schmidt F, Slaton T, Smith H, Smith S, Smith T, Suzuki T, Takano M, Takeda S, Terunuma N, Toge N, Turner J, Urakawa J, Vogel V, Woodley M, Yocky J, Young A, Zimmermann F. Extremely low vertical-emittance beam in the accelerator test facility at KEK. Phys Rev Lett 2002; 88:194801. [PMID: 12005637 DOI: 10.1103/physrevlett.88.194801] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/18/2001] [Indexed: 05/23/2023]
Abstract
Electron beams with the lowest, normalized transverse emittance recorded so far were produced and confirmed in single-bunch-mode operation of the Accelerator Test Facility at KEK. We established a tuning method of the damping ring which achieves a small vertical dispersion and small x-y orbit coupling. The vertical emittance was less than 1% of the horizontal emittance. At the zero-intensity limit, the vertical normalized emittance was less than 2.8 x 10(-8) rad m at beam energy 1.3 GeV. At high intensity, strong effects of intrabeam scattering were observed, which had been expected in view of the extremely high particle density due to the small transverse emittance.
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Affiliation(s)
- K Kubo
- High Energy Accelerator Research Organization, Tsukuba 305-0801, Japan
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26
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Kaito C, Kai M, Higo T, Takayama E, Fukamachi H, Sekimizu K, Shiokawa K. Activation of the maternally preset program of apoptosis by microinjection of 5-aza-2'-deoxycytidine and 5-methyl-2'-deoxycytidine-5'-triphosphate in Xenopus laevis embryos. Dev Growth Differ 2001; 43:383-90. [PMID: 11473545 DOI: 10.1046/j.1440-169x.2001.00579.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [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: 11/20/2022]
Abstract
The present study examines the effects on embryogenesis of microinjecting Xenopus laevis fertilized eggs with 5-aza-2'-deoxycytidine (5-Aza-CdR), which induces hypomethylation of DNA, and 5-methyl-2'- deoxycytidine-5'-triphosphate (5-methyl-dCTP), which induces hypermethylation of DNA. Embryos injected with either one of these analogs cleaved normally until the mid-blastula stage, but underwent massive cell dissociation and stopped development at the early gastrula stage. Dissociated cells that appeared here were positive by terminal deoxyribonucleotidyl transferase-mediated deoxyuridine triphosphate-digoxigenin nick end-labeling and contained fragmented nuclei with condensed chromatin. The DNA from these cells formed a "ladder" on electrophoresis. Furthermore, the induction of cell dissociation by 5-Aza-CdR and 5-methyl-dCTP was postponed by 2-3 h by co-injection of Bcl-2 mRNA and the normal metabolite (CdR and dCTP, respectively). Using a specific antibody against 5-methyl-cytosine, we confirmed that 5-Aza-CdR induces hypomethylation, whereas 5-methyl-dCTP induces hypermethylation in X. laevis embryos before the onset of cell dissociation. Incorporation of radioactive precursors revealed that synthesis of DNA, and also RNA, is inhibited significantly in both 5-Aza-CdR-injected and 5-methyl-dCTP-injected embryos. These results show that 5-Aza-CdR and 5-methyl-dCTP are incorporated into DNA and induce apoptosis, probably through alteration of DNA methylation coupled with inhibition of DNA replication and/or transcription.
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Affiliation(s)
- C Kaito
- Laboratory of Molecular Embryology, Department of Biological Sciences, Graduate School of Science, University of Tokyo, Hongo 7-3-1, Bunkyo-ku, Tokyo 113-0033, Japan
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27
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Miyata K, Shimokawa H, Kandabashi T, Higo T, Morishige K, Eto Y, Egashira K, Kaibuchi K, Takeshita A. Rho-kinase is involved in macrophage-mediated formation of coronary vascular lesions in pigs in vivo. Arterioscler Thromb Vasc Biol 2000; 20:2351-8. [PMID: 11073837 DOI: 10.1161/01.atv.20.11.2351] [Citation(s) in RCA: 145] [Impact Index Per Article: 6.0] [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: 11/16/2022]
Abstract
We have previously shown that long-term treatment with an inflammatory cytokine from the adventitia causes the development of coronary vascular lesions, with the accumulation of macrophages. Recent studies in vitro have suggested that small G-protein Rho and its effector, Rho-kinase/ROK/ROCK, may be the key molecules for various cellular functions, including cell adhesion and movement. In this study, we examined whether adventitia-derived macrophages cause the formation of coronary vascular lesions in vivo and, if so, whether Rho-kinase is involved in the process. Porcine coronary segments from the adventitia were chronically treated with monocyte chemoattractant protein-1 alone, oxidized low density lipoprotein alone, or both. Vascular lesion formation (neointimal formation and development of vascular remodeling) was mostly enhanced at the coronary segment cotreated with monocyte chemoattractant protein-1 and oxidized low density lipoprotein, where the phosphorylation of myosin binding subunit of myosin phosphatase was increased, indicating an increased activity of Rho-kinase in vivo. Histological examination demonstrated that macrophages were accumulated at the adventitia and thereafter migrated into the vascular wall. Long-term oral treatment with fasudil, which is metabolized to a specific Rho-kinase inhibitor (hydroxyfasudil) after oral absorption, markedly inhibited the myosin binding subunit phosphorylation, the macrophage accumulation and migration, and the coronary lesion formation in vivo. These results indicate that Rho-kinase is involved in macrophage-mediated formation of coronary vascular lesions in our porcine model in vivo.
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Affiliation(s)
- K Miyata
- Department of Cardiovascular Medicine, Kyushu University Graduate School of Medical Sciences, Fukuoka, Japan
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28
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Abstract
To clarify whether acute medial necrosis of the aorta induces aneurysms and intimal thickening at a later stage, we first attempted to induce acute aortic medial necrosis in 47 normal rabbits by the administration of Russell's viper venom intraperitoneally and of angiotensin II intravenously as used in a previous study and then followed the rabbits for 1 and 2 months respectively. As a control, 18 adult normal rabbits were used. Six control and 20 treated rabbits were sacrificed after aortagraphy at the end of one month, while the remaining 12 control and 27 treated rabbits were sacrificed at the end of 2 months. We evaluated the aortic lesions by gross observations and both light and electron microscopic examinations. In addition, at the end of one month, aortagraphy was performed to measure the luminal diameter of the aorta of the 6 control and 20 treated rabbits. We macroscopically found the saccular lesions to be surrounded by small crater like lesions mainly at the thoracic aortas in 18 out of 47 treated rabbits. These lesions consisted of the necrosis and calcification of the aortic media and the destruction of the elastic fiber along with intimal thickening. However, no aneurysmal dilatation was found in the aortagraphy findings. We thus conclude that acute medial necrosis produced saccular and crater like lesions but these lesions were not confirmed by aortagraphy.
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Affiliation(s)
- M Nakamura
- The Graduate School of Health and Nutrition Sciences, Nakamura Gakuen University, Fukuoka, Japan
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29
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Kai M, Higo T, Yokoska J, Kaito C, Kajita E, Fukamachi H, Takayama E, Igarashi K, Shiokawa K. Overexpression of S-adenosylmethionine decarboxylase (SAMDC) activates the maternal program of apoptosis shortly after MBT in Xenopus embryos. Int J Dev Biol 2000; 44:507-10. [PMID: 11032186] [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] [Subscribe] [Scholar Register] [Indexed: 02/17/2023]
Abstract
Overexpression of S-adenosylmethionine decarboxylase (SAMDC) mRNA in 1- and 2-cell stage Xenopus embryos induces cell autonomous dissociation at the late blastula stage and developmental arrest at the early gastrula stage. The induction of cell dissociation took place "punctually" at the late blastula stage in the SAMDC-overexpressing cells, irrespective of the stage of the microinjection of SAMDC mRNA. When we examined the cells undergoing the dissociation, we found that they were TUNEL-positive and contained fragmented nuclei with condensed chromatin and fragmented DNA. Furthermore, by injecting Xenopus Bcl-2 mRNA together with SAMDC mRNA, we showed that SAMDC-overexpressing embryos are rescued completely by Bcl-2 and becometadpoles. These results indicatethat cell dissociation induced by SAMDC overexpression is due to apoptotic cell death. Since the level of S-adenosylmethionine (SAM) is greatly reduced in SAMDC-overexpressing embryos and this induces inhibition of protein synthesis accompanied by the inhibition of DNA and RNA syntheses, we conclude that deficiency in SAM induced by SAMDC overexpression activates the maternal program of apoptosis in Xenopus embryos at the late blastula stage, but not before. We propose that this mechanism serves as a surveillance mechanism to check and eliminate cells physiologically damaged during the cleavage stage.
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Affiliation(s)
- M Kai
- Department of Biological Sciences, Graduate School of Science, University of Tokyo, Japan
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30
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Shiokawa K, Kai M, Higo T, Kaito C, Yokoska J, Yasuhiko Y, Kajita E, Nagano M, Yamada Y, Shibata M, Muto T, Shinga J, Hara H, Takayama E, Fukamachi H, Yaoita Y, Igarashi K. Maternal program of apoptosis activated shortly after midblastula transition by overexpression of S-adenosylmethionine decarboxylase in Xenopus early embryos. Comp Biochem Physiol B Biochem Mol Biol 2000; 126:149-55. [PMID: 10874162 DOI: 10.1016/s0305-0491(00)00193-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [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
When we studied polyamine metabolism in Xenopus embryos, we cloned the cDNA for Xenopus S-adenosylmethionine decarboxylase (SAMDC), which converts SAM (S-adenosylmethionine), the methyl donor, into decarboxylated SAM (dcSAM), the aminopropyl donor, and microinjected its in vitro transcribed mRNA into Xenopus fertilized eggs. We found here that the mRNA injection induces a SAM deficient state in early embryos due to over-function of the overexpressed SAMDC, which in turn induces inhibition of protein synthesis. Such embryos developed quite normally until blastula stage, but stopped development at the early gastrula stage, due to induction of massive cell dissociation and cell autolysis, irrespective of the dosage and stage of the mRNA injection. We found that the dissociated cells were TUNEL-positive, contained fragmented nuclei with ladder-forming DNA, and furthermore, rescued completely by coinjection of Bcl-2 mRNA. Thus, overexpression of SAMDC in Xenopus embryos appeared to switch on apoptotic program, probably via inhibition of protein synthesis. Here, we briefly review our results together with those reported from other laboratories. After discussing the general importance of this newly discovered apoptotic program, we propose that the maternal program of apoptosis serves as a surveillance mechanism to eliminate metabolically severely-damaged cells and functions as a 'fail-safe' mechanism for normal development in Xenopus embryos.
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Affiliation(s)
- K Shiokawa
- Laboratory of Molecular Embryology, Department of Biological Sciences, Graduate School of Science, University of Tokyo, Japan.
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Abstract
Primary vaginal adenocarcinoma unrelated to in utero exposure to diethylstilbestrol (DES) is very uncommon. We report a case of 65-year-old Japanese woman who presented with primary adenocarcinoma in the anterior wall of the vagina, where the left ureter-like metanephric duct remnant abnormally terminated. Histological examination in serial sections revealed the direct connection between the carcinoma and the metanephric duct remnant. Moreover, the remnant epithelium showed varying degrees of dysplastic changes, including carcinoma in situ in close proximity to the carcinoma. This patient also had a bicornate uterus and left renal aplasia. To our knowledge, this is the first reported case of a primary vaginal adenocarcinoma arising from the metanephric duct remnant. Although the precise mechanism involved in carcinogenesis in this clinicopathological setting remains unknown, adenocarcinoma should be included in the differential diagnosis of vaginal tumors in patients with renal aplasia and/or an ectopic termination of the ureter or metanephric duct remnant, especially when the tumor is in the anterior wall.
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Affiliation(s)
- Y Shimao
- Department of Pathology, Miyazaki Medical College Hospital, Kiyotake, Japan
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32
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Kandabashi T, Shimokawa H, Miyata K, Kunihiro I, Kawano Y, Fukata Y, Higo T, Egashira K, Takahashi S, Kaibuchi K, Takeshita A. Inhibition of myosin phosphatase by upregulated rho-kinase plays a key role for coronary artery spasm in a porcine model with interleukin-1beta. Circulation 2000; 101:1319-23. [PMID: 10725293 DOI: 10.1161/01.cir.101.11.1319] [Citation(s) in RCA: 180] [Impact Index Per Article: 7.5] [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: 11/16/2022]
Abstract
BACKGROUND We recently demonstrated that the Rho-kinase-mediated pathway plays an important role for coronary artery spasm in our porcine model with interleukin-1beta (IL-1beta). In this study, we examined whether or not Rho-kinase is upregulated at the spastic site and if so, how it induces vascular smooth muscle hypercontraction. METHODS AND RESULTS Segments of the left porcine coronary artery were chronically treated from the adventitia with IL-1beta-bound microbeads. Two weeks after the operation, as reported previously, intracoronary serotonin repeatedly induced coronary hypercontractions at the IL-1beta-treated site both in vivo and in vitro, which were markedly inhibited by Y-27632, one of the specific inhibitors of Rho-kinase. Reverse transcription-polymerase chain reaction analysis demonstrated that the expression of Rho-kinase mRNA was significantly increased in the spastic compared with the control segment. Western blot analysis showed that during the serotonin-induced contractions, the extent of phosphorylation of the myosin-binding subunit of myosin phosphatase (MBS), one of the major substrates of Rho-kinase, was significantly greater in the spastic than in the control segment and that the increase in MBS phosphorylations was also markedly inhibited by Y-27632. There was a highly significant correlation between the extent of MBS phosphorylations and that of contractions. CONCLUSIONS These results indicate that Rho-kinase is upregulated at the spastic site and plays a key role in inducing vascular smooth muscle hypercontraction by inhibiting myosin phosphatase through the phosphorylation of MBS in our porcine model.
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Affiliation(s)
- T Kandabashi
- Departments of Cardiovascular Medicine, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
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Morishige K, Shimokawa H, Yamawaki T, Miyata K, Eto Y, Kandabashi T, Yogo K, Higo T, Egashira K, Ueno H, Takeshita A. Local adenovirus-mediated transfer of C-type natriuretic peptide suppresses vascular remodeling in porcine coronary arteries in vivo. J Am Coll Cardiol 2000; 35:1040-7. [PMID: 10732906 DOI: 10.1016/s0735-1097(99)00625-7] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.5] [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: 10/18/2022]
Abstract
OBJECTIVE This study was designed to examine whether or not adenovirus-mediated gene transfer of C-type natriuretic peptide (CNP) can prevent coronary restenotic changes after balloon injury in pigs in vivo. BACKGROUND Gene therapy to prevent restenosis after percutaneous transluminal coronary angioplasty (PTCA) might be useful but requires a method applicable for in vivo gene delivery into the coronary artery as well as the efficient vector encoding a potent antiproliferative substance. We tested whether the adenovirus-mediated gene transfer of CNP by use of an infiltrator angioplasty balloon catheter (IABC) might prevent the coronary restenotic changes after balloon injury. METHODS Balloon angioplasty was performed in the left anterior descending and the left circumflex coronary artery in pigs. Immediately after the balloon injury, adenovirus solution encoding either CNP (AdCACNP) or beta-galactosidase (AdCALacZ) gene was injected with IABC into the balloon-injured coronary segments. Expression of CNP was assessed by immunohistochemical staining and cyclic guanosine 3',5'-monophosphate (cGMP) measurement. Coronary restenotic changes were evaluated by both angiographic and histological examinations. RESULTS CNP was highly expressed in the media and the adventitia of the coronary artery at the AdCACNP-transfected but not at the AdCALacZ-transfected segment. In the AdCALacZ-transfected segment, vascular cGMP levels tended to be reduced as compared with the untreated segment, whereas in the AdCACNP-transfected segment, vascular cGMP levels were restored. Angiographic coronary stenosis was significantly less at the AdCACNP-transfected than at the AdCALacZ-transfected segment. Histological examination revealed that this was achieved primarily by the marked inhibition of the geometric remodeling of the coronary artery by the CNP gene transfer. CONCLUSIONS Adenovirus-mediated CNP gene transfer with the IABC system may be a useful gene therapy to prevent restenosis after PTCA in vivo.
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Affiliation(s)
- K Morishige
- Department of Cardiovascular Medicine, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
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Miyata K, Shimokawa H, Higo T, Yamawaki T, Katsumata N, Kandabashi T, Tanaka E, Takamura Y, Yogo K, Egashira K, Takeshita A. Sarpogrelate, a selective 5-HT2A serotonergic receptor antagonist, inhibits serotonin-induced coronary artery spasm in a porcine model. J Cardiovasc Pharmacol 2000; 35:294-301. [PMID: 10672864 DOI: 10.1097/00005344-200002000-00018] [Citation(s) in RCA: 53] [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: 11/25/2022]
Abstract
Serotonin is one of the most important vasoactive substances and has been implicated in the pathogenesis of coronary artery spasm and of acute coronary syndrome. We have recently demonstrated that local and long-term treatment with interleukin-1beta(IL-1beta) causes coronary arteriosclerotic changes and hyperconstrictive responses to serotonin in pigs in vivo. However, it remains to be examined which serotonergic (5-HT) receptor subtype mediates coronary spasm and whether alterations in serotonergic receptors are involved in the abnormality. In this study, we examined the inhibitory effect of sarpogrelate, a selective 5-HT2A serotonergic receptor antagonist, on the serotonin-induced coronary spasm as well as the possible alterations of serotonergic receptors in our porcine model. A segment of the porcine coronary artery was carefully dissected and aseptically wrapped with cotton mesh absorbing IL-1beta-bound microbeads from the adventitia. Two weeks after the procedure, angiographic study was performed, followed by binding assay for 5-HT1B and 5-HT2A serotonergic receptors and reverse transcription-polymerase chain reaction (RT-PCR) analysis for mRNA of those receptors. Angiographic study showed coronary vasospastic responses to serotonin at the IL-1beta-treated site. Sarpogrelate dose-dependently inhibited the serotonin-induced coronary spasm, but it did not affect the prostaglandin F2alpha-induced vasoconstriction. Radiolabeled receptor-binding assay showed that receptor affinity or receptor number of the 5-HT1B, or 5-HT2A receptors did not differ significantly between the spastic and the control sites. Furthermore, RT-PCR analysis showed that the expression of neither 5-HT2A nor 5-HT1B receptor mRNA was significantly altered at the spastic site. These results indicate that serotonin-induced coronary spasm is mediated primarily by 5-HT2A receptor in our porcine model, although the 5-HT2A receptor was not up-regulated, suggesting that alteration in the signal-transduction pathway for vascular smooth muscle contraction beyond the 5-HT2A receptor plays a primary role in the pathogenesis of coronary spasm in our porcine model.
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Affiliation(s)
- K Miyata
- Department of Cardiovascular Medicine, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan
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Miyata K, Shimokawa H, Yamawaki T, Kunihiro I, Zhou X, Higo T, Tanaka E, Katsumata N, Egashira K, Takeshita A. Endothelial vasodilator function is preserved at the spastic/inflammatory coronary lesions in pigs. Circulation 1999; 100:1432-7. [PMID: 10500045 DOI: 10.1161/01.cir.100.13.1432] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.8] [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: 11/16/2022]
Abstract
BACKGROUND The question of whether or not endothelial vasodilator function in the spastic coronary artery is preserved is still controversial. We recently developed a porcine model in which long-term and local treatment with interleukin-1beta (IL-1beta) from the adventitial site causes coronary arteriosclerotic changes and vasospastic responses to autacoids. The aim of this study was to examine the endothelial vasodilator function in our new porcine model of the spasm both in vivo and in vitro. METHODS AND RESULTS A segment of the porcine coronary artery was aseptically wrapped with cotton mesh that held absorbed IL-1beta-bound microbeads. Two weeks after the procedure, intracoronary administration of serotonin caused coronary vasospasm at the IL-1beta-treated site (n = 10). Coronary vasodilatation to bradykinin, substance P, or an increase in coronary blood flow was preserved at the spastic site. Vasodilator responses to 3-morpholinosydnonimine (an NO donor) and nitroglycerin also were comparable between the 2 sites. The vasoconstricting response to N(G)-monomethyl-L-arginine and the extent of the augmentation of the serotonin-induced vasoconstriction were comparable between the 2 sites. Organ chamber experiments showed that endothelium-dependent relaxations to bradykinin, the calcium ionophore A23187, and even the vasospastic agonist serotonin were preserved at the spastic site, whereas contractions to serotonin were augmented at the spastic site regardless of the presence or absence of the endothelium (n = 6). Endothelium-independent relaxations to sodium nitroprusside were also preserved at the spastic site. CONCLUSIONS These results indicate that endothelial vasodilator function is preserved at the spastic site and that the spasm is caused primarily by smooth muscle hypercontraction in our porcine model.
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Affiliation(s)
- K Miyata
- Research Institute of Angiocardiology and Cardiovascular Clinic, Kyushu University School of Medicine, Fukuoka, Japan
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36
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Shiokawa K, Kai M, Higo T, Fukamachi H, Takayama E. [Transcription in Xenopus early embryos and apoptotic program preset in the fertilized egg]. Tanpakushitsu Kakusan Koso 1999; 44:32-41. [PMID: 10025171] [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: 02/10/2023]
Affiliation(s)
- K Shiokawa
- Department of Biological Sciences, Graduate School of Science, University of Tokyo, Japan
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Yamawaki T, Shimokawa H, Kozai T, Miyata K, Higo T, Tanaka E, Egashira K, Shiraishi T, Tamai H, Igaki K, Takeshita A. Intramural delivery of a specific tyrosine kinase inhibitor with biodegradable stent suppresses the restenotic changes of the coronary artery in pigs in vivo. J Am Coll Cardiol 1998; 32:780-6. [PMID: 9741527 DOI: 10.1016/s0735-1097(98)00312-x] [Citation(s) in RCA: 109] [Impact Index Per Article: 4.2] [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: 11/17/2022]
Abstract
OBJECTIVES This study was designed to examine whether or not intramural delivery of ST638 (a specific tyrosine kinase inhibitor) with biodegradable stent can suppress the restenotic changes of the coronary artery in vivo. BACKGROUND Clinical and animal studies demonstrated that restenosis after coronary intervention results from a combined effect of neointimal formation and geometric remodeling (decrease in total cross-sectional area). Thus, the most effective strategy to prevent the restenosis appears to inhibit both the neointimal formation and geometric remodeling by antiproliferative agent and stent, respectively. We have previously shown that ST638 markedly suppresses the restenotic changes of the porcine coronary artery when applied from the adventitial site. METHODS A poly-L-lactic acid biodegradable stent was coated with either ST638 (0.8 mg) or equimolar of its inactive metabolite, ST494. A pair of these stents were implanted alternatively in the left anterior descending or circumflex coronary artery in pigs (n=6). Three weeks after the procedure, coronary stenosis was assessed by angiography followed by histological examination. RESULTS Coronary stenosis was significantly less at the ST638 stent site than at the ST494 stent site (47+/-5% vs. 25+/-4%, p < 0.01). Histological examination also showed that the extent of neointimal formation and that of geometric remodeling were significantly less at the ST638 stent site than at the ST494 stent site (p < 0.05). CONCLUSIONS These results indicate that intramural delivery of a specific tyrosine kinase inhibitor with biodegradable stent overcomes the proliferative stimuli caused by balloon injury, the stent itself, and the drug coating on the stent, resulting in the suppression of the restenotic changes of the coronary artery in vivo. This strategy might also be useful in the clinical setting in humans.
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Affiliation(s)
- T Yamawaki
- Research Institute of Angiocardiology and Cardiovascular Clinic, Kyushu University School of Medicine, Fukuoka, Japan
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Abstract
Twenty-one days of magnesium sulfate tocolysis were performed on a 28-year-old woman because of preterm labor at 31 weeks gestation. In association with this tocolysis, urinary calculus of magnesium ammonium phosphate occurred at 34 weeks gestation.
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Affiliation(s)
- H Sameshima
- Perinatal Center, Miyazaki Medical College, Japan
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Nakamura T, Hasebe M, Yamakawa M, Higo T, Suzuki H, Kobayashi K. Effect of dietary fiber on bowel mucosal integrity and bacterial translocation in burned rats. J Nutr Sci Vitaminol (Tokyo) 1997; 43:445-54. [PMID: 9328863 DOI: 10.3177/jnsv.43.445] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [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
The response of the bowel mucosa to enteral formula supplemented with dietary fiber was examined in rats with 30% full-thickness burns. The rats were fed a standard enteral formula without fiber or with one of two types of fiber (insoluble soy fiber or soluble guar gum fiber). Seventy-two hours after burn injury, the mesenteric lymph nodes were excised aseptically for bacterial culturing. Samples of the jejunum, ileum and cecum were also collected for histological examination. There were significantly fewer bacterial colonies in the lymph node cultures from rats given soy fiber compared to those from rats fed no fiber. In rats given soy fiber, the integrity of the bowel mucosa was maintained in the jejunum, ileum and cecum. In rats given guar gum fiber, however, the repair of mucosal erosions was observed in the jejunum and ileum as well as flattening of the cecal mucosa. These findings indicate that soy fiber is superior to guar gum fiber for maintaining bowel mucosal integrity and preventing bacterial translocation in burned rats receiving enteral feeding.
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Affiliation(s)
- T Nakamura
- Third Department of Surgery, Faculty of Medicine, Tokyo University, Japan
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Tokunaga Y, Nakayama N, Ishikawa Y, Nishitai R, Irie A, Kaganoi J, Ohsumi K, Higo T. Surgical risks of acute cholecystitis in elderly. Hepatogastroenterology 1997; 44:671-6. [PMID: 9222669] [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] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
BACKGROUND/AIMS For the elderly patient, an emergency biliary procedure carries a higher risk than an elective operation. Recently introduced advances in ultrasonography and critical care medicine have affected the clinical risks of surgery for acute cholecystitis in the elderly. This study evaluated the clinical risks of open cholecystectomy for the elderly with acute cholecystitis. MATERIALS AND METHODS During a 10 year period (1985-1994), a total of 145 patients were diagnosed with acute cholecystitis and underwent cholecystectomy. According to their age, the patients were divided into 3 groups (Group A < 59 years of age; Group B between 60-69 years of age; Group C > 70 years of age). The characteristics and the surgical risk factors in open cholecystectomy for the elderly with acute cholecystitis were evaluated. RESULTS The rate of acalculous cholecystitis and choledochal stones were significantly (p < 0.05) high in Group C. Septic complication, gangrenous changes, and positive bile culture were also increased parallel to the increase in age. A noteworthy finding was an incidental carcinoma found in a case in group B and in 3 cases in group C. Hospital stay was significantly longer in Group C than in the other groups due to pre-operative complications and post-operative morbidity. CONCLUSION With respect to increase in elderly patients with acute cholecystitis who present more frequent gangrenous changes and carcinomatous changes as well as high rate of septic complication, successful treatment of these patients is increased when early surgery can be performed on the basis of accurate and prompt diagnosis using imaging modalities and meticulous peri-operative management.
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Affiliation(s)
- Y Tokunaga
- Department of Surgery, Maizuru Municipal Hospital
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Adolphsen C, Bane K, Higo T, Kubo K, Miller R, Ruth R, Thompson K, Wang J. Measurement of wake-field suppression in a detuned X-band accelerator structure. Phys Rev Lett 1995; 74:2475-2478. [PMID: 10057937 DOI: 10.1103/physrevlett.74.2475] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
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Kaneko M, Haruyama Y, Higo T, Fujisaki S. [A case of cor triatriatum diagnosed in pregnancy]. Nihon Sanka Fujinka Gakkai Zasshi 1993; 45:387-90. [PMID: 8509675] [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: 01/31/2023]
Affiliation(s)
- M Kaneko
- Department of Obstetrics and Gynecology, Miyazaki Prefectural Nichinan Hospital
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Hakoshima T, Oka K, Toda S, Tanaka M, Goda K, Higo T, Itoh T, Minami H, Tomita K, Nishikawa S. Crystallographic characterization of wild-type and mutant ribonuclease T1 complexes with several ribonucleotides. J Biochem 1990; 108:695-8. [PMID: 2081729 DOI: 10.1093/oxfordjournals.jbchem.a123265] [Citation(s) in RCA: 3] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Ribonuclease T1 and the mutant enzymes were cocrystallized with several ribonucleotides, including non-hydrolyzable substrate analogs of di- and triribonucleotides, which have a novel guanylate in which the 2'-hydroxyl group of the ribose is replaced by a fluorine atom. One of the mutant enzymes has a tryptophan residue, instead of Tyr45 of the wild-type enzyme, to enhance the binding of ribonucleotides to the enzyme and the other mutant enzyme has histidine and aspartate residues, instead of Asn43 and Asn44, respectively, to reproduce the natural substitutions found in ribonuclease Ms. Polymorphism of the crystals was observed for wild-type and mutant enzymes. However, orthorhombic crystals, which are virtually all isomorphous to each other, were successfully obtained from wild-type and mutant (Y45W) enzymes by the macroscopic seeding technique using mother crystals of the wild-type ribonuclease T1 complexed with 2'GMP or 3'GMP. The diffraction patterns of these crystals extend beyond 2.5 A resolution and the diffraction data were collected from some of the crystals on a diffractometer up to a range of 2.5 to 1.8 A resolution.
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Affiliation(s)
- T Hakoshima
- Faculty of Pharmaceutical Sciences, Osaka University, Suita
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Takagu M, Higo T, Mori H, Sato Y. [Comlications of epidural anesthesia. 1. Case of incomplete paralysis of the sciatic nerve]. Masui 1973; 22:1502-6. [PMID: 4799487] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
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