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6. Prevalence of transthyretin amyloidosis among heart failure patients with preserved ejection fraction in Japan

Author

Naito, Takanori, Nakamura, Kazufumi, Abe, Yukio, Watanabe, Hiroyuki, Sakuragi, Satoru, Katayama, Yusuke, Kihara, Hajime, Okizaki, Atsutaka, Kawai, Yusuke, Yoshikawa, Masaki, Takaishi, Atsushi, Fujio, Hideki, Otsuka, Hiroaki, Ogura, Soichiro, Ito, Hiroshi, ATTR HFpEF Registry Investigators, Naito, Takanori, Nakamura, Kazufumi, Abe, Yukio, Watanabe, Hiroyuki, Sakuragi, Satoru, Katayama, Yusuke, Kihara, Hajime, Okizaki, Atsutaka, Kawai, Yusuke, Yoshikawa, Masaki, Takaishi, Atsushi, Fujio, Hideki, Otsuka, Hiroaki, Ogura, Soichiro, Ito, Hiroshi, and ATTR HFpEF Registry Investigators

Abstract

Aims Heart failure with preserved ejection fraction (HFpEF), which is caused by wide various conditions, has become a major public health problem. Transthyretin amyloid cardiomyopathy (ATTR-CM), which is thought to be an underdiagnosed disease, can cause HFpEF. Non-invasive diagnosis using 99mTechnetium (Tc)-pyrophosphate (PYP) scintigraphy enables accurate diagnosis of ATTR-CM. The aim of this study was to clarify the prevalence and characteristics of ATTR-CM among Japanese patients with HFpEF. Methods and results This study was a multicentre, prospective, observational study conducted in Japan. We enrolled 373 patients with HFpEF [left ventricular (LV) ejection fraction ≥50%] aged ≥65 years who were admitted to the department of cardiology from September 2018 to January 2022. A 99mTc-PYP scintigraphy scan was performed during admission in all eligible patients. Cardiac 99mTc-PYP retention was graded according to a previously reported visual scale ranging from 0 to 3 points. The scan was considered positive when it revealed moderate-to-severe 99mTc-PYP uptake (Grade 2–3) in both ventricles. Patients were divided into ATTR-CM and non-ATTR-CM patients according to positive (Grade 2–3) or negative (Grade 0–1) 99mTc-PYP scintigraphy, respectively. Medical history, blood tests, electrocardiogram, echocardiography, and magnetic resonance imaging in the two groups of patients were compared. Among the 373 patients with HFpEF, 53 patients (14.2%; 95% confidence interval: 10.7–17.7) showed positive uptake on 99mTc-PYP scintigraphy. An endomyocardial biopsy was performed in 32 patients and confirmed amyloidosis in all cases. There were no significant differences between the two groups in age, severity of heart failure as assessed by the New York Heart Association (NYHA) functional classification, renal function values, left ventricular ejection fraction, and tricuspid regurgitant pressure gradient (ATTR-CM, n = 53 vs. non-ATTR-CM, n = 320). Patients in the ATTR-CM group h

Published
2023

13. Possible Protective Effect of Remote Ischemic Preconditioning on Acute Kidney Injury Following Elective Percutaneous Coronary Intervention: Secondary Analysis of a Multicenter, Randomized Study

Author

Otsuka, Hiroaki, Miyoshi, Toru, Ejiri, Kentaro, Kohno, Kunihisa, Nakahama, Makoto, Doi, Masayuki, Munemasa, Mitsuru, Murakami, Masaaki, Nakamura, Kazufumi, and Ito, Hiroshi

Subjects
Aged, 80 and over, Male, stable angina, Contrast Media, Acute Kidney Injury, Middle Aged, Creatine, behavioral disciplines and activities, serum creatinine, Percutaneous Coronary Intervention, Humans, Female, remote ischemic preconditioning, Ischemic Preconditioning, Aged
Abstract

Remote ischemic preconditioning (RIPC) is a promising strategy for protecting against ischemic reperfusion injury. This study is a secondary analysis of a randomized study that aimed to evaluate the effect of RIPC on the early increase in serum creatinine (SCr) following percutaneous coronary intervention (PCI), which is associ-ated with contrast-induced acute kidney injury. Patients with stable angina undergoing elective PCI were assigned to control, RIPC, and continuous infusion of nicorandil (nicorandil) groups. The endpoint of this study was the incidence of the early increase in SCr, a predictor of contrast-induced acute kidney injury, which was defined as either a > 20% or absolute increase by 0.3 mg/dl of SCr levels after 24 h of PCI. This study included 220 patients for whom a dataset of SCr values was available. The incidence of the early increase in SCr was significantly lower in the RIPC than in the control (1.3% vs 10.8%, p = 0.03) group, but was not significantly different between the nicorandil and control groups. In multivariate analysis, RIPC remained a significant fac-tor associated with a reduction in the incidence of early increase in SCr. RIPC reduces the incidence of early increase in SCr in patients with stable angina following elective PCI.

Published
2021

14. Current status of a helicopter transportation system on remote islands for patients undergoing mechanical thrombectomy

Author

Hiu, Takeshi, Morimoto, Shimpei, Matsuo, Ayaka, Satoh, Kei, Otsuka, Hiroaki, Kutsuna, Fumiya, Ozono, Keisuke, Hirayama, Kosuke, Nakamichi, Chikaaki, Yamasaki, Kazumi, Ogawa, Yuka, Shiozaki, Eri, Morofuji, Yoichi, Kawahara, Ichiro, Horie, Nobutaka, Tateishi, Yohei, Ono, Tomonori, Haraguchi, Wataru, Izumo, Tsuyoshi, Tsujino, Akira, Matsuo, Takayuki, Tsutsumi, Keisuke, Hiu, Takeshi, Morimoto, Shimpei, Matsuo, Ayaka, Satoh, Kei, Otsuka, Hiroaki, Kutsuna, Fumiya, Ozono, Keisuke, Hirayama, Kosuke, Nakamichi, Chikaaki, Yamasaki, Kazumi, Ogawa, Yuka, Shiozaki, Eri, Morofuji, Yoichi, Kawahara, Ichiro, Horie, Nobutaka, Tateishi, Yohei, Ono, Tomonori, Haraguchi, Wataru, Izumo, Tsuyoshi, Tsujino, Akira, Matsuo, Takayuki, and Tsutsumi, Keisuke

Abstract

Background: Mechanical thrombectomy (MT) is standard treatment for acute ischemic stroke (AIS) with large-vessel occlusion within 6 h of symptom onset to treatment initiation (OTP). Recent trials have extended the therapeutic time window for MT to within 24 h. However, MT treatment remains low in remote areas. Nagasaki Prefecture, Japan has many inhabited islands with no neurointerventionalists. Our hospital on the mainland is a regional hub for eight island hospitals. We evaluated clinical outcomes of MT for patients with AIS on these islands versus on the mainland. Methods: During 2014–2019, we reviewed consecutive patients with AIS who received MT at our hospital. Patients comprised the Islands group and Mainland group. Patient characteristics and clinical outcomes were compared between groups. Results: We included 91 patients (Islands group: 15 patients, Mainland group: 76 patients). Seven patients (46.7%) in the Islands group versus 43 (56.6%) in the Mainland group achieved favorable outcomes. Successful recanalization was obtained in 11 patients (73.3%) on the islands and 67 (88.2%) on the mainland. The median OTP time in the Islands was 365 min. In both the Islands and Mainland groups, the OTP time and successful recanalization were associated with functional outcome. The modified Rankin Scale (mRS) score at 90 days ≤2 was obtained in two patients and mRS = 3 in four patients among eight patients with OTP time >6 h. Conclusions: Few patients with AIS on remote islands have received MT. Although patients who underwent MT on the islands had longer OTP, the clinical outcomes were acceptable. OTP time on remote islands must be shortened, as this is related to functional outcome. In some cases with successful recanalization, a favorable outcome can still be obtained even after 6 h. Even if OTP exceeds 6 h, it is desirable to appropriately select patients and actively perform MT., PLOS ONE, 16(1), e0245082; 2021

Published
2021

16. Fibrosis‐4 index reflects right ventricular function and prognosis in heart failure with preserved ejection fraction

Author

Nakashima, Mitsutaka, primary, Sakuragi, Satoru, additional, Miyoshi, Toru, additional, Takayama, Shin, additional, Kawaguchi, Tatsuto, additional, Kodera, Nobuhisa, additional, Akai, Hiroaki, additional, Koide, Yuji, additional, Otsuka, Hiroaki, additional, Wada, Tadashi, additional, Kawamoto, Kenji, additional, Tanakaya, Machiko, additional, Katayama, Yusuke, additional, and Ito, Hiroshi, additional

Published
2021
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17. Current status of a helicopter transportation system on remote islands for patients undergoing mechanical thrombectomy

Author

Hiu, Takeshi, primary, Morimoto, Shimpei, additional, Matsuo, Ayaka, additional, Satoh, Kei, additional, Otsuka, Hiroaki, additional, Kutsuna, Fumiya, additional, Ozono, Keisuke, additional, Hirayama, Kosuke, additional, Nakamichi, Chikaaki, additional, Yamasaki, Kazumi, additional, Ogawa, Yuka, additional, Shiozaki, Eri, additional, Morofuji, Yoichi, additional, Kawahara, Ichiro, additional, Horie, Nobutaka, additional, Tateishi, Yohei, additional, Ono, Tomonori, additional, Haraguchi, Wataru, additional, Izumo, Tsuyoshi, additional, Tsujino, Akira, additional, Matsuo, Takayuki, additional, and Tsutsumi, Keisuke, additional

Published
2021
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18. Case series of acute ischemic stroke with tandem lesions of intracranial large vessel occlusion and cervical internal carotid artery stenosis or occlusion

Author

Otsuka, Hiroaki, primary, Hiu, Takeshi, additional, Kawahara, Ichiro, additional, Iwanaga, Hiroshi, additional, Chikamatsu, Genki, additional, Matsuo, Ayaka, additional, Ono, Tomonori, additional, Haraguchi, Wataru, additional, Ushijima, Ryujiro, additional, and Tsutsumi, Keisuke, additional

Published
2021
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21. Flux pinning in Nb-Ti based nanoscale superconducting multilayers

Author

Oguma, Hidetaka, Osamura, Kozo, Sakai, akira, Otsuka, Hiroaki, and Ito, Ikuo

Subjects
Superconductors -- Research, Business, Electronics, Electronics and electrical industries
Abstract

Plastic deformation methods were used to fabricate nanoscale Nb-Ti/Nb/Cu-Ni-Si-Zn multilayers.

Published
2001

29. Efficacy of the Drip and Ship Method in 24-h Helicopter Transportation and Teleradiology for Isolated Islands

Author

HIU, Takeshi, primary, OZONO, Keisuke, additional, KAWAHARA, Ichiro, additional, YAMASAKI, Kazumi, additional, SATOH, Kei, additional, OTSUKA, Hiroaki, additional, NAKAMICHI, Chikaaki, additional, IWANAGA, Hiroshi, additional, FUKUDA, Yutaka, additional, HONDA, Kazuya, additional, HIU, Hiroyuki, additional, ONO, Tomonori, additional, HARAGUCHI, Wataru, additional, USHIJIMA, Ryujiro, additional, and TSUTSUMI, Keisuke, additional

Published
2019
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30. Fatigue‐resistant Fe‐Mn‐Si‐based alloy seismic dampers to counteract long‐period ground motion.

Author

Inoue, Yasuhiko, Kushibe, Atsumichi, Umemura, Kenji, Mizushima, Yasunori, Sawaguchi, Takahiro, Nakamura, Terumi, Otsuka, Hiroaki, and Chiba, Yuya

Subjects
SEISMIC response, STEEL framing, BUILDING performance, MOTION, FATIGUE life, ALLOYS, CYCLIC loads, STEEL fatigue
Abstract

In recent years, resonance in high‐rise buildings due to long‐period ground motion, which induces large‐amplitude cyclic deformation of seismic dampers, has become a matter of significant concern. Performance requirements for seismic dampers that are installed in vibration‐controlled buildings have become more stringent, and durability against cyclic deformation has become essential. An Fe‐15Mn‐4Si‐10Cr‐8Ni alloy with enhanced low‐cycle fatigue resistance has been developed to produce steel seismic dampers that are durable against large‐amplitude cyclic deformations. We used this alloy to develop two types of fatigue‐resistant seismic dampers (shear panel and brace‐type) that counteract long‐period ground motion. Furthermore, cyclic loading tests were conducted to validate the deformation performance and fatigue resistance of the developed damper. The results indicated that these dampers exhibit significantly better fatigue life than conventional steel dampers and exhibit outstanding deformation performance and durability under low‐cycle fatigue. The proposed two types of dampers were installed on steel structure buildings in Japan. These dampers ensured that the buildings with seismic performance margins can withstand long‐period and long‐duration ground motion and repeated after‐quakes. [ABSTRACT FROM AUTHOR]

Published
2021
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32. Magnetic shielding from alternating magnetic field by NbTi/Nb/Cu superconducting multilayer composite cylinder

Author

Otsuka, Hiroaki and Itoh, Ikuo

Subjects
Magnetic fields -- Analysis, Niobium alloys -- Analysis, Physics
Abstract

The NbTi/Nb/Cu superconducting multilayer composite cylinder is studied at liquid-helium temperatures after magnetic shielding from alternating magnetic fields. The alternating magnetic field has a frequency between 40 to 500 Hz. The cylinder exhibits a magnetic shielding to the order of 10 raised to the power of minus 4. The field frequency influences the magnetic shielding properties.

Published
1994

35. An increase in the coronary calcification score is associated with an increased risk of heart failure in patients without a history of coronary artery disease

Author

Sakuragi, Satoru, primary, Ichikawa, Keishi, additional, Yamada, Keiji, additional, Tanimoto, Masafumi, additional, Miki, Takashi, additional, Otsuka, Hiroaki, additional, Yamamoto, Kazuhiko, additional, Kawamoto, Kenji, additional, Katayama, Yusuke, additional, Tanakaya, Machiko, additional, and Ito, Hiroshi, additional

Published
2016
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37. Structural elements responsible for the glucosidic linkage-selectivity of a glycoside hydrolase family 13 exo-glucosidase

Author

Saburi, Wataru, Rachi-Otsuka, Hiroaki, Hondoh, Hironori, Okuyama, Masayuki, Mori, Haruhide, Kimura, Atsuo, Saburi, Wataru, Rachi-Otsuka, Hiroaki, Hondoh, Hironori, Okuyama, Masayuki, Mori, Haruhide, and Kimura, Atsuo

Abstract

Glycoside hydrolase family 13 contains exo-glucosidases specific for alpha-(1 -> 4)- and alpha-(1 -> 6)-linkages including alpha-glucosidase, oligo-1,6-glucosidase, and dextran glucosidase. The alpha-(1 -> 6)-linkage selectivity of Streptococcus mutans dextran glucosidase was altered to alpha-(1 -> 4)-linkage selectivity through site-directed mutations at Val195, Lys275, and Glu371. V195A showed 1300-fold higher k(cat)/K-m for maltose than wild-type, but its k(cat)/K-m for isomaltose remained 2-fold higher than for maltose. K275A and E371A combined with V195A mutation only decreased isomaltase activity. V195A/K275A, V195A/E371A, and V195A/K275A/E371A showed 27-, 26-, and 73-fold higher k(cat)/K-m for maltose than for isomaltose, respectively. Consequently, the three residues are structural elements for recognition of the alpha-(1 -> 6)-glucosidic linkage. (C) 2015 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved.

Published
2015

42. High Sensitivity Cardiac Troponin T Reflects Presence of Left Ventricular Hypertrophy and Diastolic Dysfunction and Predicts Incidence of Cardiac Events

Author

Otsuka, Hiroaki, primary, Sakuragi, Satoru, additional, Yamada, Keiji, additional, Tanimoto, Masafumi, additional, Fujiwara, Takashi, additional, Miki, Takashi, additional, Yamamoto, Kazuhiko, additional, Kawamoto, Kenji, additional, Katayama, Yusuke, additional, and Tanakaya, Machiko, additional

Published
2013
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