120 results on '"E. Miyata"'
Search Results
2. Development of prototype RICH detector with multi-anode photomultipliers for radioactive ions
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K. Chikaato, Takayuki Yamaguchi, N. Kanda, R. Ishii, Takuji Izumikawa, M. Machida, A. Homma, Takashi Ohtsubo, Jiro Shimaya, T. Tahara, E. Miyata, M. Nassurlla, Yukichi Tanaka, K. Ohnishi, M. Amano, Tetsuaki Moriguchi, S. Sato, Mitsunori Fukuda, A. Mizukami, Shigekazu Fukuda, Y. Kamisho, D. Nishimura, Jyunsei Chiba, Mototsugu Mihara, S. Yagi, Atsushi Kitagawa, M. Nagashima, H. Du, S. N. Nakamura, Shinji Suzuki, S. Kanbe, T. Hori, A. Ikeda, R. Kehl, M. Tanaka, Kensaku Matsuta, S. Yamaoka, Toshio Suzuki, R. Yanagihara, T. Sugihara, and Maya Takechi
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Physics ,Mass number ,Nuclear and High Energy Physics ,Photomultiplier ,010308 nuclear & particles physics ,Analytical chemistry ,01 natural sciences ,Particle identification ,Anode ,Ion ,0103 physical sciences ,Nuclide ,010306 general physics ,Instrumentation ,Beam (structure) ,Cherenkov radiation - Abstract
RI-RICH, a ring-imaging Cherenkov counter for radioactive ions, has been developed to measure the velocity of the ions at intermediate energies. Our RI-RICH system consists of six multi-anode photomultiplier tubes covered with 360-nm bandpass filters and a radiator made of quartz or BK7. For the primary 132Xe beam with a velocity of β = 0 . 712 , a velocity resolution of Δ β ∕ β = 4 . 9 × 1 0 − 4 (one standard deviation σ ) and a detection efficiency of more than 99.99% were achieved. For the secondary beams with Z = 44 – 55 and β ≃ 0 . 70 , we successfully performed particle identification using the B ρ - Δ E - β method. The velocity resolutions of RI-RICH for these nuclides were equivalent to a more than 6 σ separation for the mass number.
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- 2019
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3. A novel radiation detector based on Gd2O3 doped organic semiconductor for the detection of γ and β-particles
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E. Fukasawa, H. Miyata, E. Miyata, M. Katsumata, H. Sato, H. Ono, M. Watanabe, E. Saito, Y. Seino, A. Umeyama, M. Sato, M. Tamura, and T. Suzuki
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Nuclear and High Energy Physics ,Instrumentation - Published
- 2022
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4. Development of a Method to Deduce Point-proton Radii from Charge Changing Cross Sections
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D. Nagae, N. Kanda, M. Amano, K. Nishizuka, Maulen Nassurlla, A. S. Aimaganbetov, Tetsuaki Moriguchi, Daiki Kamioka, Yukichi Tanaka, Mototsugu Mihara, I. Kato, Kensaku Matsuta, H. Arakawa, Hans Geissel, H. Takeda, Takuji Izumikawa, C. Scheidenberger, N. Burtebayev, E. Miyata, Mitsunori Fukuda, S. Yagi, T. K. Zholdybayev, A. Homma, R. Yanagihara, T. Fujii, K. Chikaato, Momoko Tanaka, K. Nishimuro, Takashi Ohtsubo, Naohito Inabe, I. Kenzhina, K. Wakayama, Z. Korkulu, Masao Ohtake, T. Sugihara, D. Nishimura, T. Wada, Maya Takechi, H. Suzuki, Takayuki Yamaguchi, Toshio Suzuki, R. Igosawa, Kensuke Kusaka, A. Ikeda, K. Inomata, T. Hori, K. Ohnishi, Y. Shimizu, S. Hoshino, S. Ohmika, S. Bagchi, S. Nakamura, K. Itahashi, H. Du, A. Prochazka, Y. K. Tanaka, A. Ozawa, Hooi Jin Ong, Ye. Kuk, Y. Yanagisawa, S. Suzuki, N. Fukuda, K. H. Behr, K. Yoshida, Toshiyuki Sumikama, D. S. Ahn, and Hiroyoshi Sakurai
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Baryon ,Physics ,Proton ,Nuclear Theory ,Hadron ,Elementary particle ,Charge (physics) ,Atomic physics ,Nuclear Experiment ,Nucleon ,Glauber ,Energy (signal processing) - Abstract
Charge changing cross sections (\(\sigma _{\text{CC}}\)) for ^40–48K and ^42–51Ca have been measured using BigRIPS at RIBF, RIKEN. The \(\sigma _{\text{CC}}\) obtained along the long isotopic chain of K and Ca revealed the fact that \(\sigma _{\text{CC}}\) have strong proton separation energy () dependence. The data are compared with the calculation based on the Glauber model and also with the proton evaporation model. It is found that the \(\sigma _{\text{CC}}\) data are well reproduced when the proton evaporation effect is taken into account.
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- 2020
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5. Swelling of Doubly Magic Ca48 Core in Ca Isotopes beyond N=28
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K. Itahashi, M. Amano, H. Du, S. Nakamura, Isao Tanihata, R. Igosawa, K. Ohnishi, Mototsugu Mihara, Mitsunori Fukuda, Z. Korkulu, I. Kato, Naohito Inabe, H. Takeda, N. Burtebayev, Maulen Nassurlla, R. Yanagihara, Kensaku Matsuta, N. Kanda, Hiroyoshi Sakurai, I. Kenzhina, Y. Shimizu, Masao Ohtake, T. Sugihara, K. Inomata, Maya Takechi, T. Hori, H. Suzuki, K. Yoshida, T. Wada, T. K. Zholdybayev, E. Miyata, S. Yagi, Toshio Suzuki, Momoko Tanaka, S. Hoshino, Y. Kuk, S. Ebata, K. Wakayama, H. Arakawa, A. Ikeda, Kensuke Kusaka, A. Ozawa, S. Suzuki, N. Fukuda, K. Nishizuka, Hooi Jin Ong, A. Prochazka, D. Nagae, S. Bagchi, Y. Yanagisawa, S. Omika, K. H. Behr, Y. K. Tanaka, A. S. Aimaganbetov, Yukichi Tanaka, Takuji Izumikawa, C. Scheidenberger, A. Homma, Takashi Ohtsubo, Tetsuaki Moriguchi, D. Nishimura, Daiki Kamioka, T. Fujii, K. Chikaato, K. Nishimuro, Takayuki Yamaguchi, Wataru Horiuchi, D. S. Ahn, Hans Geissel, and Toshiyuki Sumikama
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Physics ,Isotope ,Nuclear Theory ,General Physics and Astronomy ,Neutron density ,01 natural sciences ,Skin thickness ,Mean field theory ,Neutron number ,0103 physical sciences ,medicine ,Neutron ,Swelling ,medicine.symptom ,Atomic physics ,Nuclear Experiment ,010306 general physics ,Nucleon - Abstract
Interaction cross sections for ^{42-51}Ca on a carbon target at 280 MeV/nucleon have been measured for the first time. The neutron number dependence of derived root-mean-square matter radii shows a significant increase beyond the neutron magic number N=28. Furthermore, this enhancement of matter radii is much larger than that of the previously measured charge radii, indicating a novel growth in neutron skin thickness. A simple examination based on the Fermi-type distribution, and mean field calculations point out that this anomalous enhancement of the nuclear size beyond N=28 results from an enlargement of the core by a sudden increase in the surface diffuseness of the neutron density distribution, which implies the swelling of the bare ^{48}Ca core in Ca isotopes beyond N=28.
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- 2020
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6. Hybrid semiconductor radiation detectors using conductive polymers
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M. Katsumata, A. Umeyama, Toshio Suzuki, E. Fukasawa, H. Miyata, M. Sato, E. Miyata, H. Abe, K. Kakizaki, and M. Tamura
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Physics ,Conductive polymer ,Nuclear and High Energy Physics ,Fabrication ,business.industry ,01 natural sciences ,Particle detector ,010305 fluids & plasmas ,Semiconductor detector ,Organic semiconductor ,chemistry.chemical_compound ,Semiconductor ,chemistry ,0103 physical sciences ,Polyaniline ,Electrode ,Optoelectronics ,010306 general physics ,business ,Instrumentation - Abstract
Organic semiconductor radiation detectors have been developed using conductive polymers as sensor materials. Unlike the commonly used inorganic semiconductor detectors, the use of organic semiconductor detectors has facilitated large-scale fabrication of cheap and flexible detectors. In this study, a sensor is fabricated to improve the radiation sensitivity by combining an n-type titanium oxide (TiO2) semiconductor as an additive with a p-type polyaniline (Pani) semiconductor. A maximum detection efficiency of 10% for β -rays was achieved using a new comb-type electrode. We report the performance of the newly developed hybrid sensors, such as the incident rate dependence of detection efficiency and the long-term stability.
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- 2020
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7. Development Of Ring-imaging Cherenkov Counter For Heavy Ions
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S. Yagi, E. Miyata, Shinji Sato, Mototsugu Mihara, Shigekazu Fukuda, Tetsuaki Moriguchi, M. Fukuda, S. Nakamura, N. Kanda, H. Hosokawa, M. Machida, K. Ohnishi, A. Ikeda, T. Tahara, H. Oikawa, D. Nishimura, Jyunsei Chiba, Tomofumi Yamaguchi, I. Kato, Atsushi Kitagawa, M. Tanaka, T. Suzuki, Takuji Izumikawa, J. Ohnishi, H. Du, A. Homma, Takashi Ohtsubo, M. Takechi, R. Ishii, M. Amano, and M. Tada
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Physics ,Nuclear physics ,Photon ,Meson ,Physics::Instrumentation and Detectors ,Ionization chamber ,Atomic number ,Particle identification ,Cherenkov radiation ,Lepton ,Ion - Abstract
Up to this day, RICHes have been mainly used for high energy experiments to identify leptons and mesons. On the other hand, the number of Cherenkov photons is proportional to square of the atomic number, so that application of a RICH for heavy ions is expected. Then we are developing a ring-imaging Cherenkov counter for heavy ions (HI-RICH). The experiment was performed at NIRS-HIMAC. As for the primary beam ($^{132}$Xe with an energy of 420 MeV/u), a velocity resolution $\Delta\beta/\beta=0.050\%$ (standard deviation $\sigma$) and a detection efficiency $\varepsilon=99.9\%$ were achieved. Regarding to the secondary beam, a particle identification was successfully performed with HI-RICH and an ion chamber.
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- 2017
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8. Preparation of new lipases derivatives with high activity–stability in anhydrous media: adsorption on hydrophobic supports plus hydrophilization with polyethylenimine
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Peter J. Halling, Jose M. Guisan, Roberto Fernandez-Lafuente, D Re, Pilar Sabuquillo, Gloria Fernández-Lorente, D Kennedy, Cesar Mateo, and E Miyata
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biology ,Immobilized enzyme ,Process Chemistry and Technology ,Triacylglycerol lipase ,Bioengineering ,Biochemistry ,Lauric acid ,Catalysis ,Enzyme catalysis ,Hydrophilization ,chemistry.chemical_compound ,Isoelectric point ,chemistry ,biology.protein ,Anhydrous ,Organic chemistry ,Lipase - Abstract
A novel method to prepare immobilized lipases derivatives is hereby proposed. Lipases are firstly adsorbed on supports having large internal surfaces covered by hydrophobic groups (e.g. polyacrylic resins covered by C18 moieties). Then, immobilized lipases are incubated in the presence of polyethyleneimine (PEI) at a pH value over the isoelectric point of the enzyme in order to cover the lipase surface with this polymer. In this way, we try to minimize all possible direct interactions between immobilized lipase and organic solvents when using these derivatives in anhydrous media. Lipases from Rhizomucor miehie (RML) and Candida rugosa (CRL) were immobilized according to the proposed protocol. These derivatives were very active and very stable when catalyzing esterifications and transesterifications in anhydrous media. For example, RML derivatives exhibited a very high synthetic activity (more than 1000 Units/g immobilized biocatalyst) even when catalyzing the esterification of lauric acid with octanol at water activity values very close to zero. On the contrary, covalently immobilized derivatives exhibited a much lower synthetic activity under similar conditions (less than 10 Units/g of immobilized biocatalyst). Moreover, these new RML derivatives preserve 100% activity after incubation for 3 days in anhydrous butanone in the presence of molecular sieves. Under the same conditions, commercial immobilized RML lost more than 90% of activity in less than 10 min.
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- 2001
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9. Case report: coexistence of pheochromocytoma and bilateral aldosterone-producing adenomas in a 36-year-old woman
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E Miyata, S Momosaki, S Sakata, Takuya Tsuchihashi, A Iguchi, and Yuko Ohta
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endocrine system ,medicine.medical_specialty ,Aldosterone ,endocrine system diseases ,Adenoma ,business.industry ,medicine.drug_class ,medicine.medical_treatment ,Aldosterone metabolism ,medicine.disease ,Pheochromocytoma ,chemistry.chemical_compound ,Steroid hormone ,Endocrinology ,chemistry ,Mineralocorticoid ,Internal medicine ,Internal Medicine ,medicine ,business - Abstract
Case report: coexistence of pheochromocytoma and bilateral aldosterone-producing adenomas in a 36-year-old woman
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- 2010
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10. The hard X-ray response of the XIS-CCD for Astro-E: qualification of the X-ray CCD detector
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Hiroshi Murakami, Masaaki Sakano, John P. Doty, Hisamitsu Awaki, M. Ozaki, Marshall W. Bautz, E Miyata, Kiyoshi Hayashida, H. Tsunemi, S. Kitamoto, Kenji Hamaguchi, Steven E. Kissel, Katsuji Koyama, George R. Ricker, Mamiko Nishiuchi, R. Foster, Tadayasu Dotani, and Takeshi Go Tsuru
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Physics ,Nuclear and High Energy Physics ,business.industry ,Astrophysics::High Energy Astrophysical Phenomena ,Resolution (electron density) ,X-ray ,Imaging spectrometer ,Linearity ,Optics ,Quantum efficiency ,Ccd detector ,business ,Instrumentation ,Line (formation) - Abstract
We report on the hard X-ray response of the CCD detector for the X-ray imaging spectrometer (XIS), to be launched on the next Japanese X-ray Astronomical Satellite, ASTRO-E, in February 2000. XIS is prepared by an international team, comprised of MIT (USA), ISAS, Osaka University and Kyoto University (JAPAN). We have evaluated the X-ray response of the XIS in its high-energy band (1.5–10 keV). Data from the fluorescent line emission of Al, Cl, Ti, Ni, Fe, Zn, Se were used to construct the response function of the CCD detectors. Details of the response function – including the energy-scale, linearity, energy resolution, quantum efficiency –, are given as a function of incident X-ray energy. We find that the tail component of high-energy photopeaks are produced by events with incomplete charge collection. We also conclude that the size of the charge clouds can be estimated using the shapes of the tail components.
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- 1999
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11. Nuclear Structure of $^{15,16}$C via Reaction Cross-section Measurements
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S. Yamaoka, Takuji Izumikawa, Takashi Ohtsubo, Daiki Nishimura, K. Hori, Toshio Suzuki, Shinji Suzuki, H. Du, I. Kato, Takayuki Yamaguchi, M. Tanaka, Maya Takechi, T. Takemoto, Shinji Sato, Y. Kanke, H. Kikuchi, D. Murooka, E. Miyata, U. Sayama, Y. Takeuchi, Atsushi Kitagawa, R. Tamura, Mototsugu Mihara, Yukichi Tanaka, J. Ohno, J. Nagumo, N. Tadano, H. Oikawa, Jiro Shimaya, K. Nishizuka, K. Abe, S. Fukuda, M. Fukuda, A. Mizukami, and S. Matsunaga
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Physics ,Nuclear physics ,Cross section (physics) ,010308 nuclear & particles physics ,0103 physical sciences ,Nuclear structure ,General Physics and Astronomy ,010306 general physics ,01 natural sciences - Published
- 2017
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12. Reaction Cross Sections for $^{13-15}$B and One-neutron Halo in $^{14}$B
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Y. Morita, Y. Kanke, J. Kohno, Takayuki Yamaguchi, Momoko Tanaka, Takashi Suzuki, E. Miyata, Daiki Nishimura, Y. Kamisho, H. Du, K. Ohnishi, H. Oikawa, R. Takagaki, M. Nagashima, S. Fukuda, I. Kato, M. Fukuda, D. Murooka, A. Honma, M. Takechi, S. Yamaki, T. Nagai, J. Ohno, J. Muraoka, Shinji Sato, Mototsugu Mihara, A. Takenouchi, S. Yagi, N. Tadano, Y. Takei, H. Shimamura, Kensaku Matsuta, N. Kanda, M. Machida, Takuji Izumikawa, Takashi Ohtsubo, K. Aoki, Yukichi Tanaka, Shinji Suzuki, A. Kitagawa, S. Yamaoka, and T. Sugihara
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Nuclear physics ,Physics ,010308 nuclear & particles physics ,0103 physical sciences ,General Physics and Astronomy ,Neutron ,Halo ,010306 general physics ,01 natural sciences - Published
- 2017
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13. Development of High Resolution TOF Detector for RI Beams Using Cherenkov Radiation
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A. Mizukami, A. Kitagawa, M. Tanaka, K. Abe, Toshio Suzuki, Takuji Izumikawa, Y. Kanke, Mitsunori Fukuda, J. Muraoka, K. Aoki, Takashi Ohtsubo, Ryosuke Kanbe, I. Kato, N. Tadano, Mototsugu Mihara, S. Ohmika, S. Yagi, S. Fukuda, Y. Takeuchi, Shinji Suzuki, E. Miyata, Yukichi Tanaka, M. Takechi, S. Yamaoka, Shinji Sato, H. Takahashi, K. Chikaato, T. Nishimura, K. Ohnishi, Takayuki Yamaguchi, Y. Takei, D. Nishimura, K. Yokoyama, H. Shimamura, H. Du, H. Kikuchi, R. Takagaki, T. Takenouchi, H. Oikawa, Jiro Shimaya, J. Nagumo, A. Ikeda, N. Kanda, M. Machida, and K. Nishizuka
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Physics ,Optics ,Cherenkov detector ,law ,business.industry ,Detector ,General Physics and Astronomy ,High resolution ,business ,Cherenkov radiation ,law.invention - Published
- 2017
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14. Articulated tracked vehicle with four degrees of freedom
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T. Yamada, S. Sasaki, and E. Miyata
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Economic efficiency ,Transport engineering ,Engineering ,Pitch control ,Adverse conditions ,business.industry ,Mechanical Engineering ,Degrees of freedom ,Terrain ,business ,Marine engineering - Abstract
Presently, silvicultural operations in Japan are limited because of problems associated with the lack of technically sound and economically efficient equipment and systems for use under the adverse working conditions encountered in Japan. Some characteristics that contribute to the adverse working conditions are steep slopes, fragile soils and rugged terrain. The Japanese Forestry and Forest Products Research Institute has been studying to develop an articulated tracked vehicle (all-terrain vehicle) for use under those adverse conditions. This paper describes the design, unique features and operational characteristics of the articulated tracked vehicle and presents preliminary results from the field test of the vehicle to examine the effect of the active pitch control for traveling on steep slopes.
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- 1991
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15. Performance and current status of Monitor of All-sky X-ray Image on the International Space Station
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M. Suzuki, M. Matsuoka, K. Kawasaki, S. Ueno, H. Tomida, M. Kohama, M. Ishikawa, H. Katayama, T. Mihara, N. Isobe, H. Tsunemi, E. Miyata, H. Negoro, M. Nakajima, N. Kawai, J. Kataoka, A. Yoshida, K. Yamaoka, M. Morii, M. Galassi, David Palmer, and Ed Fenimore
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Physics ,Sky ,media_common.quotation_subject ,International Space Station ,X ray image ,Astronomy ,Gamma-ray burst ,Remote sensing ,media_common - Abstract
Monitor of All‐sky X‐ray Image (MAXI) will be launched and attached on the International Space Station (ISS) next year. MAXI scans the sky while ISS goes around the Earth and provides an all sky X‐ray image every orbit. MAXI has two types of X‐ray instruments: gas‐proportional counters for 2–30 keV and CCD cameras for 0.5–10 keV. MAXI will be able to transmit alerts to the Internet on X‐ray transients including bright X‐ray afterglows.
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- 2008
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16. Quasi-resonant ZVS-PWM inverter-fed DC-DC converter for microwave oven and its input harmonic current evaluations
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S. Hishikawa, E. Miyata, K. Matsumoto, Izuo Hirota, D. Bessyo, Hideki Omori, K. Yasoi, and M. Nakaoka
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Engineering ,business.industry ,Buck converter ,Boost converter ,Electrical engineering ,Buck–boost converter ,Electronic engineering ,Power factor ,AC power ,business ,Pulse-width modulation ,AC/AC converter ,Negative impedance converter - Abstract
In this paper, a circuit topology of an active voltage clamped quasi-resonant PWM inverter-type DC-DC converter using IGBTs is proposed in order to improve the function of conventional single-ended soft switching converter for a magnetron drive. This converter includes some advantages capable of clamping the peak voltage across the main power semiconductor switching device. In addition, the anode current was reduced by up to 1.2 A with a magnetron as a load of this converter. Furthermore, the special modulation pattern for the operating frequency and PWM of the inverter is also proposed in order to improve line current distortion and power factor in utility AC power side. Harmonic current components in utility grid AC power side are regulated under the condition of the peak value limitation of the anode current of magnetron and soft switching PWM strategy.
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- 2003
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17. Internal states of pulse-type hardware neuron model with chaotic dynamics
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Hidekazu Shinozaki, Yoshifumi Sekine, E. Miyata, and Kazutaka Someya
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Nervous system ,Quantitative Biology::Neurons and Cognition ,Artificial neural network ,business.industry ,Computer science ,Property (programming) ,Chaotic ,Information processing ,Biological neuron model ,Type (model theory) ,Pulse (physics) ,medicine.anatomical_structure ,medicine ,business ,Computer hardware - Abstract
Information processing in living organisms is carried out by the nervous system. From an engineering viewpoint, the nervous system has various interesting features. So, it is necessary to study the hardware neuron model for its engineering applications. On the other hand, it is suggested that a new information processing structure can be realized in a neural network with a neuron model with chaotic dynamics. We discuss the internal states of a pulse-type hardware neuron model ("P-HNM"), and its response characteristics to periodic pulses. As a result, it is verified that the P-HNM has the properties of the chaotic neuron model, it also exhibits chaos phenomena, resembling the property of actual neurons, and it is available as the chaotic neuron model.
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- 2002
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18. A study on the bursting firing phenomena in neural network with the hardware neuron model
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E. Miyata, Y. Sekine, and K. Someya
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Physical neural network ,Nervous system ,Spiking neural network ,Neocortex ,Quantitative Biology::Neurons and Cognition ,Artificial neural network ,Time delay neural network ,Computer science ,business.industry ,Recurrent neural nets ,Biological neuron model ,Neurophysiology ,Winner-take-all ,Bursting ,medicine.anatomical_structure ,Recurrent neural network ,medicine ,business ,Computer hardware - Abstract
For information communication in a biological system, bursting firing phenomena are very often confirmed in thalamic and neocortex neurons of the brain, and contain various information on processing. We have been studying bursting firing phenomena of neurons with particular reference to the delay feedback of signals in the nervous system. We discuss bursting firing phenomena in the recurrent neural network. First, we show the negative resistance circuit and pulse type hardware neuron model with the circuit, which is an element of the neural network. Next, we show the dynamics in the self recurrent circuit and relay recurrent circuit, which are basic construction units of the recurrent neural network with the neuron model. As a result, it is verified that bursting firing phenomena can be simulated by the neural network models, where the dynamics is controlled by the external input and circuit parameters.
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- 2002
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19. Voltage-clamped soft switching PWM inverter-type DC-DC converter for microwave oven and its utility AC side harmonics evaluations
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T. Matsushige, E. Miyata, D. Bessyo, Manabu Ishitobi, Izuo Hirota, Hideki Omori, K. Yasui, and M. Nakaoka
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Engineering ,Total harmonic distortion ,business.industry ,Harmonics ,Electronic engineering ,Electrical engineering ,Inverter ,Insulated-gate bipolar transistor ,Power factor ,AC power ,business ,Power (physics) ,Voltage - Abstract
A single-ended quasi-resonant zero voltage soft-switching inverter type DC-DC converter is used to drive the magnetron for a microwave oven. This converter is simple, downsizing, high efficiency and low cost in addition to simple control scheme. However, this power conversion circuit has to control its input power under a condition of ZVS in accordance with the variable frequency regulation. The heater current variation of the magnetron becomes large when the power regulation of this inverter is implemented. The regulation range of input power is to be in order to achieve ZVS operation. For high power application, the peak voltage of IGBT in this inverter becomes large. This paper presents a new topology of the voltage-clamped ZVS-PWM high-frequency inverter-fed DC-DC converter for driving a microwave oven. This paper also describes how to improve line current distortion and power factor on the utility AC power side. Because the anode current of the magnetron must not exceed 1.2 A, because of the lifetime of the magnetron, the voltage-clamped ZVS-PWM high-frequency inverter-fed DC-DC converter is implemented and evaluated under suppression conditions of the anode peak current of the magnetron.
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- 2002
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20. [Oculomotor nerve palsy caused by the abscess of the clivus]
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E, Miyata
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Male ,Cranial Fossa, Posterior ,Oculomotor Nerve Diseases ,Humans ,Tomography, X-Ray Computed ,Magnetic Resonance Imaging ,Abscess ,Aged - Published
- 2002
21. [Intracranial lipoma in the sylvian fissure with convulsion]
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E, Miyata
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Male ,Brain Neoplasms ,Seizures ,Humans ,Lipoma ,Tomography, X-Ray Computed ,Magnetic Resonance Imaging ,Aged - Published
- 2001
22. [Cauda equina syndrome due to recurrent malignant lymphoma of the spinal cord. A case report]
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E, Miyata, H, Koga, H, Yamamoto, M, Okamoto, and M, Hirano
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Male ,Lymphoma, B-Cell ,Treatment Outcome ,Cauda Equina ,Humans ,Lymphoma, Large B-Cell, Diffuse ,Spinal Cord Neoplasms ,Polyradiculopathy ,Combined Modality Therapy ,Magnetic Resonance Imaging ,Aged - Abstract
A 50-year-old man noticed a mass in the right cervical region and presented to our hospital. He underwent biopsy of a cervical lymph node, which revealed non-Hodgkin's lymphoma (diffuse large B cell, lymphoblastic type) histologically. He was treated with chemotherapy (CHOP) and radiation, and achieved complete remission. Two months later, he was admitted because of distal pain and extensive numbness of the lower limb as well as weakness of the left leg. Lumbar MRI showed an area of abnormal intensity in the cauda equina. Cytological examination of cerebrospinal fluid showed class V (lymphoma cells), so he was diagnosed as having recurrent malignant lymphoma of the spinal cord. He was treated with intrathecal chemotherapy and irradiation. After the treatment the mass in the cauda equina disappeared and the neurological symptoms in his legs resolved. It is rare for malignant lymphoma to recur in the spinal cord, particularly the cauda equina. It is well known that cauda equina syndrome can be caused by vertebral lesions and primary spinal cord tumors, but it is also necessary to keep malignant lymphoma of the cauda equina in mind.
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- 2000
23. Observations of gamma-ray bursts with MAXI on the international space station
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N. Kawai, Hiroshi Tsunemi, E. Miyata, K. Torii, S. Ueno, A. Yoshida, Y. Shirasaki, M. Matsuoka, I. Sakurai, M. Yamauchi, H. Tomida, H. Negoro, M. Sugizaki, W. Yuan, and T. Mihara
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Physics ,Stellar wind ,Sky brightness ,Sky ,media_common.quotation_subject ,International Space Station ,Astronomy ,Field of view ,Astrophysics ,Gamma-ray burst ,media_common - Abstract
MAXI is an X-ray all-sky monitor mission which will be deployed on the Japanese Experiment Module of the International Space Station in 2004. It is designed to monitor X-ray sources by scanning the entire sky every 90 minutes, and can detect X-ray sources of 3 mCrab in one day. Although its instantaneous field of view is limited to narrow fan beams, one can expect ∼5 GRBs to occur in the field of view and ∼25 afterglows to be detected per year.
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- 2000
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24. 6639 Skeletal metastases in gastric cancer: analysis of skeletal-related events and plasma endothelin-1
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Naoyuki Katayama, Satoshi Tamaru, S. Kitano, E. Miyata, Yoshiki Yamashita, T. Mizuno, A. Hiasa, Kanako Saito, S. Kageyama, and H. Nomura
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Cancer Research ,Oncology ,business.industry ,Cancer research ,Skeletal related events ,Medicine ,Cancer ,business ,medicine.disease ,Endothelin 1 - Published
- 2009
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25. [MRI findings of acute relapsing disseminated encephalomyelitis with late onset]
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E, Miyata
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Acute Disease ,Humans ,Female ,Encephalomyelitis ,Magnetic Resonance Imaging ,Aged - Published
- 1999
26. [Spinal arteriovenous malformation with ischemic myelopathy diagnosed on high field-strength magnetic resonance imaging]
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E, Miyata, A, Kimura, M, Nomura, A, Yamamoto, and M, Shoda
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Arteriovenous Malformations ,Male ,Spinal Cord ,Ischemia ,Humans ,Magnetic Resonance Imaging ,Spinal Cord Diseases ,Aged - Published
- 1999
27. [Expiration-like movement and spino-bulbo-spinal reflex in a patient with apneic coma caused by anoxic encephalopathy]
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K, Nokura, H, Yamamoto, H, Ohsawa, E, Miyata, and H, Koga
- Subjects
Reflex, Stretch ,Medulla Oblongata ,Spinal Cord ,Apnea ,Humans ,Female ,Coma ,Parkinson Disease, Secondary ,Hypoxia, Brain ,Reflex, Abdominal ,Aged - Abstract
A 72-year-old female patient, hospitalized for parkinsonism, suffered cardiopulmonary arrest without any certain causes. The patient was successfully resuscitated and her life was sustained by artificial ventilator for 100 days. All brainstem reflexes were absent, and flat electroencephalogram and no response of brainstem auditory evoked potentials were confirmed twice with an interval of over 6 hours. Flexion of the arm induced reflex rectus abdominis muscle contraction, resembling expiratory movement. Muscle stretch reflexes on rectus abdominis were hyperactive. The expiration-like movement appeared in an apnea test seven minutes after a cessation of artificial ventilation. Electrical stimuli on femoral nerve induced complex action potentials with a 70.2 +/- 6.9 msec latency and 300 msec duration in rectus abdominis muscle, which were similar to the spino-bulbo-spinal reflex. Single photon emission tomography showed only slight cerebral cortical blood flow. The expiration-like movements observed in this case suggest a relationship not only with the spinal cord reflex but also with polysynaptic reflexes to reticular formation in the medulla oblongata.
- Published
- 1998
28. ASCA Observation of the Cygnus Loop Supernova Remnant
- Author
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E. Miyata and H. Tsunemi
- Subjects
High surface ,Physics ,Wavelength ,Brightness ,Cygnus Loop ,Astrophysics::High Energy Astrophysical Phenomena ,Astronomy ,Astrophysics ,Supernova remnant ,Near-Earth supernova ,Equivalent width ,Astrophysics::Galaxy Astrophysics - Abstract
The Cygnus Loop is the prototype shell-like supernova remnant (SNR) and one of the brighest SNRs in X-ray wavelength. We have observed the entire Cygnus Loop with the X-ray satellite, ASCA. Its large apparent size, high surface brightness, and low absorption features have made the Cygnus Loop to be an ideal target for the study of the spatially-resolved spectroscopic structure in detail. Part of this work was summarized in Miyata (1996). Here, we present the first X-ray image of the Cygnus Loop obtained with ASCA.
- Published
- 1998
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29. Non-carcinogenicity of 2,2'--(4-aminophenyl)imino-bisethanol sulfate in a long-term feeding study in Fischer 344 rats
- Author
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Akihiro Hagiwara, M.-A. Shibata, Seiko Tamano, Masao Hirose, E. Miyata, S. Sugiura, and M. Inoue
- Subjects
Male ,Carcinogenicity Tests ,Hair Dyes ,Thyroid Gland ,Physiology ,Phenylenediamines ,Toxicology ,Body weight ,Statistics, Nonparametric ,chemistry.chemical_compound ,Neoplasms ,medicine ,Animals ,Thyroid Neoplasms ,Sulfate ,Adverse effect ,Survival rate ,Carcinogen ,Incidence (epidemiology) ,Thyroid ,Body Weight ,General Medicine ,Organ Size ,Rats, Inbred F344 ,Rats ,Survival Rate ,medicine.anatomical_structure ,chemistry ,Toxicity ,Female ,Food Science - Abstract
2,2'-[(4-aminophenyl)imino]bisethanol sulfate (4APE) was administered at dietary levels of 0 (control), 300, 1000 and 3000 ppm to groups of 50 male and 50 female Fischer 344/DuCrj rats for 104 wk. As slight body weight retardation was observed in the male 3000 ppm group in the preliminary 13-wk feeding study, this dose was selected for the highest exposure level. Mean body weights of both sexes in the 3000 ppm group were lower than those of the controls from wk 2 to termination. However, there were no treatment-related clinical signs or adverse effects on survival rate, food consumption or haematology data. Very slight but statistically significant increases in relative thyroid weights were found in males of the 3000 ppm group, but there was no significant treatment-related increase in the incidence of any non-neoplastic or neoplastic lesions. Thus, under the experimental conditions used, 4APE was not carcinogenic in Fischer 344 rats of either sex.
- Published
- 1996
30. [Clinical usefulness of MRI in acute phase of spinal multiple sclerosis--influence of high-dose steroid therapy in acute phase]
- Author
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M, Nomura, A, Suzumura, H, Anno, E, Miyata, S, Koga, and H, Yamamoto
- Subjects
Adult ,Gadolinium DTPA ,Male ,Multiple Sclerosis ,Adolescent ,Middle Aged ,Pentetic Acid ,Magnetic Resonance Imaging ,Methylprednisolone ,Spinal Cord Diseases ,Spinal Cord ,Acute Disease ,Organometallic Compounds ,Humans ,Female ,Aged - Abstract
Magnetic resonance imaging (MRI) is useful for detecting spinal cord lesions in multiple sclerosis (MS). In this study, we have examined MRI for 14 patients (26 cases) with clinically definite MS and investigated the correlations between neurological and MRI findings before and after high-dose corticosteroid therapy (pulse therapy). High signal intensity areas on T2-weighted images (T2WI) were found in 25 of 26 cases. In 22 cases spinal level of clinically suspected lesions were involved in these high intensity areas. T1-weighted images (T1WI) after intravenous gadolinium with diethylenetriamine pentaacetic acid (Gd-DTPA) were also obtained and in 12 of 17 cases before pulse therapy, the symptoms and enhancement of lesions correlated well. The symptoms regressed in all cases after pulse therapy, and high-intensity areas in T2WI became less distinct. Gd-DTPA enhanced areas disappeared in 6 cases and became smaller in 3 of 12 cases. Additional pulse therapy in 3 cases effectively diminished the enhanced areas in these cases. In one patient who had repeated pulse therapy, MRI showed no enhancement. In two other patients who continued on decreased steroid dose had relapses, pulse therapy was therefore started again, providing a good recovery both clinically and radiologically. The changes of MRI findings and clinical course suggest that the pathological changes in spinal MS may be caused not only by demyelination but also by parenchymal edema. Clinical and MRI concordance was significantly better with Gd-DTPA enhanced T1WI than the high-intensity areas in T2WI. Contrast enhancement gives more information about disease activity and the reaction to therapy.
- Published
- 1995
31. 2 cases of antiphospholipid syndrome with amaurosis fugax as the major symptom
- Author
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H, Kogen, K, Ishiguro, H, Ishihara, E, Miyata, F, Sobue, I, Miyashita, K, Yamamoto, and K, Ota
- Subjects
Adult ,Male ,Humans ,Antiphospholipid Syndrome ,Blindness - Published
- 1993
32. Direct Measurement of the CCD with a Subpixel Resolution by Using a New Technique
- Author
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K. Yoshita, S. Kitamoto, E. Miyata, H. Tsunemi, and K. C. Gendreau
- Abstract
The response function of the front-illuminated CCD, like SIS on ASCA, can be devided into three parts: the gate structure transmission, the absorption efficiency in the depletion region and the charge spreading after the photo-absorption. These effect depend on both the incident X-ray energy and the landing posion of the X-ray inside the CCD pixel. Then, the measurement of the X-ray efficiency within the pixel is important for the response function of the CCD. By using a new technique, we performed an experiment using the SIS CCD chip in the GSFC in order to measure how the various types of events are formed.
- Published
- 1998
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33. [Untitled]
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K Taketa, T Kobayashi, T Takano, T Ogawa, E Miyata, T Miyazaki, Y Kaneshige, and K Kosalca
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Hepatology - Published
- 1968
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34. The earth station for TV-relay from the Antarctic continent
- Author
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K. Tsunoda, S. Mizuarai, M. Takahashi, and E. Miyata
- Subjects
Ground support equipment ,Meteorology ,Aviation ,business.industry ,Satellite television ,law.invention ,Low noise ,Geography ,Installation ,Relay ,law ,Communications satellite ,Earth (chemistry) ,business - Published
- 1980
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35. [For the healthy growth of infants--experience at the Kagoshima Tamasato Nursery]
- Author
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E, Miyata
- Subjects
Child Development ,Nurseries, Hospital ,Infant Care - Published
- 1971
36. [Treatment of nurses and working conditions hoped for]
- Author
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N, Nagumo, M, Suzuki, E, Miyata, S, Ichinose, and K, Hayakawa
- Subjects
Japan ,Economics, Nursing - Published
- 1969
37. Long-term clinical and endoscopic outcomes of ustekinumab in pediatric Crohn's disease with anti-tumor necrosis factor failure.
- Author
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Yamamoto Y, Takeuchi I, Shimizu H, Fujikawa H, Toda M, Miyata E, To H, Nagata S, and Arai K
- Abstract
Background and Aim: Only a few studies have reported the long-term effects of ustekinumab on pediatric Crohn's disease. Therefore, this study aimed to describe the long-term clinical and endoscopic outcomes of ustekinumab and its safety profile in pediatric-onset Crohn's disease with anti-tumor necrosis factor failure., Methods: Medical records of patients with pediatric-onset Crohn's disease in whom anti-tumor necrosis factor therapy failed and ustekinumab treatment was initiated from 2017 to 2022 at a Japanese tertiary children's hospital were retrospectively reviewed. The primary outcome was the continuation rates at weeks 8, 52, and 106. The secondary outcomes were the steroid-free remission rates at weeks 8, 52, and 106, changes in the Simple Endoscopic Score for Crohn's Disease, and adverse events during follow-up., Results: Forty-three patients were enrolled. The median ages at diagnosis and ustekinumab introduction were 9.7 (interquartile range: 6.7-13.0) years and 13.6 (interquartile range: 8.0-16.0) years. The median follow-up period was 136 (interquartile range: 102-172) weeks. The continuation rates were 100%, 91%, and 80% at weeks 8, 52, and 106, respectively. The incidence of discontinuation was 6.2% per patient-year of follow-up. The steroid-free remission rates were 44%, 71%, and 80% at weeks 8, 52, and 106, respectively. The Simple Endoscopic Score for Crohn's Disease of patients in clinical remission at the last follow-up significantly decreased (P < 0.01), and the safety profile was acceptable., Conclusions: Ustekinumab appeared effective in maintaining long-term clinical remission with endoscopic improvement in pediatric-onset Crohn's disease with anti-tumor necrosis factor failure., (© 2024 Journal of Gastroenterology and Hepatology Foundation and John Wiley & Sons Australia, Ltd.)
- Published
- 2024
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38. Unveiling the Threat of Maternal Advanced Glycation End Products to Fetal Muscle: Palmitoleic Acid to the Rescue.
- Author
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Yoshizaki H, Kawaharada R, Tsutsumi S, Okami H, Toriumi A, Miyata E, and Nakamura A
- Subjects
- Female, Animals, Pregnancy, Rats, Cell Line, Cell Survival drug effects, Mice, Dietary Supplements, Proto-Oncogene Proteins c-akt metabolism, Oxidative Stress drug effects, Insulin Resistance, Humans, Phosphorylation, Rats, Sprague-Dawley, Pregnancy in Diabetics metabolism, Pregnancy in Diabetics drug therapy, Male, Fetal Development drug effects, Fatty Acids, Monounsaturated pharmacology, Glycation End Products, Advanced metabolism, Receptor for Advanced Glycation End Products metabolism, Muscle, Skeletal metabolism, Muscle, Skeletal drug effects, Reactive Oxygen Species metabolism
- Abstract
Advanced glycation end products (AGEs) accumulate in the plasma of pregnant women with hyperglycemia, potentially inducing oxidative stress and fetal developmental abnormalities. Although intrauterine hyperglycemia has been implicated in excessive fetal growth, the effects of maternal AGEs on fetal development remain unclear. We evaluated the differentiation regulators and cellular signaling in the skeletal muscles of infants born to control mothers (ICM), diabetic mothers (IDM), and diabetic mothers supplemented with either cis-palmitoleic acid (CPA) or trans-palmitoleic acid (TPA). Cell viability, reactive oxygen species levels, and myotube formation were assessed in AGE-exposed C2C12 cells to explore potential mitigation by CPA and TPA. Elevated receptors for AGE expression and decreased Akt and AMPK phosphorylation were evident in rat skeletal muscles in IDM. Maternal palmitoleic acid supplementation alleviated insulin resistance by downregulating RAGE expression and enhancing Akt phosphorylation. The exposure of the C2C12 cells to AGEs reduced cell viability and myotube formation and elevated reactive oxygen species levels, which were attenuated by CPA or TPA supplementation. This suggests that maternal hyperglycemia and plasma AGEs may contribute to skeletal muscle disorders in offspring, which are mitigated by palmitoleic acid supplementation. Hence, the maternal intake of palmitoleic acid during pregnancy may have implications for fetal health.
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- 2024
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39. Accuracy of Transperineal Ultrasonography for Assessing Rectal Lesions in Paediatric Ulcerative Colitis: A Prospective Study.
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Jimbo K, Hosoi K, Suzuki M, Kyodo R, Maruyama K, Arai N, Sato M, Miyata E, Hoshino E, Kudo T, and Shimizu T
- Subjects
- Child, Humans, Prospective Studies, Severity of Illness Index, Colonoscopy, Ultrasonography, Leukocyte L1 Antigen Complex, Colitis, Ulcerative diagnostic imaging, Colitis, Ulcerative pathology
- Abstract
Background and Aims: Transabdominal ultrasonography [TAUS] appears comparable to colonoscopy for evaluating ulcerative colitis [UC] activity, but it has low accuracy in rectal evaluation. In this study, the accuracy of transperineal ultrasonography [TPUS] for evaluating rectal activity was compared to that of colonoscopy in paediatric UC cases., Methods: Faecal calprotectin [FCP] values and TPUS and colonoscopic findings were compared prospectively in paediatric UC cases. Rectal wall thickening [RWT] and rectal wall flow [RWF] on power Doppler evaluated by TPUS were compared with the colonoscopy findings and were also measured on TAUS and assessed for the concordance rate of each finding., Results: Thirty Mayo endoscopic sub-score [MES] 0-1 UC cases and 57 MES 2-3 UC cases were enrolled. FCP, RWT and RWF showed significant differences between the two groups [p < 0.05]. RWT and RWF were independent predictors of UC endoscopic activity, showing sensitivity of 95.8% and specificity of 100% with RWT ≥ 4.5 mm and positive RWF. The concordance rates between TPUS and TAUS findings in MES 2-3 were moderate to fair, whereas those in MES 0-1 were fair to poor. The concordance rates between ultrasonic examiners were good for both TAUS and TPUS., Conclusions: TPUS may evaluate rectal activity of UC with accuracy comparable to endoscopy. If accurate ultrasonic screening for the total colon can be performed by TPUS and TAUS, repeated evaluation of short-term treatment response may be possible., (© The Author(s) 2023. Published by Oxford University Press on behalf of European Crohn’s and Colitis Organisation. All rights reserved. For permissions, please email: journals.permissions@oup.com.)
- Published
- 2023
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40. Refractory pediatric ulcerative colitis responding to high dose tofacitinib.
- Author
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Miyata E, Arai K, Takeuchi I, Shimizu H, and Shimizu T
- Subjects
- Child, Humans, Pyrimidines therapeutic use, Piperidines, Colitis, Ulcerative diagnosis, Colitis, Ulcerative drug therapy
- Published
- 2023
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- View/download PDF
41. Potential Anti-allergic Effects of Bibenzyl Derivatives from Liverworts, Radula perrottetii.
- Author
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Asai H, Kato K, Suzuki M, Takahashi M, Miyata E, Aoi M, Kumazawa R, Nagashima F, Kurosaki H, Aoyagi Y, and Fukuishi N
- Subjects
- Animals, Cell Degranulation, Immunoglobulin E, Interleukin-4 metabolism, Interleukin-4 pharmacology, Leukotriene B4 metabolism, Leukotriene B4 pharmacology, Mast Cells, Mice, Mice, Inbred C57BL, Phospholipase C gamma metabolism, Phospholipase C gamma pharmacology, Receptors, IgE metabolism, Anti-Allergic Agents pharmacology, Bibenzyls metabolism, Bibenzyls pharmacology, Hepatophyta
- Abstract
The liverwort Radula perrottetii contains various bibenzyl derivatives which are known to possess various biological activities, such as anti-inflammatory effects. Mast cells (MC) play crucial roles in allergic and inflammatory diseases; thus, inhibition of MC activation is pivotal for the treatment of allergic and inflammatory disorders. We investigated the effects of perrottetin D (perD), isolated from Radula perrottetii , and perD diacetate (Ac-perD) on antigen-induced activation of MCs. Bone marrow-derived MCs (BMMCs) were generated from C57BL/6 mice. The degranulation ratio, histamine release, and the interleukin (IL)-4 and leukotriene B
4 productions on antigen-triggered BMMC were investigated. Additionally, the effects of the bibenzyls on binding of IgE to Fc ε RI were observed by flow cytometry, and signal transduction proteins was examined by Western blot. Furthermore, binding of the bibenzyls to the Fyn kinase domain was calculated. At 10 µM, perD decreased the degranulation ratio (p < 0.01), whereas 10 µM Ac-perD down-regulated IL-4 production (p < 0.05) in addition to decreasing the degranulation ratio (p < 0.01). Both compounds tended to decrease histamine release at a concentration of 10 µM. Although 10 µM perD reduced only Syk phosphorylation, 10 µM Ac-perD diminished phosphorylation of Syk, Gab2, PLC- γ , and p38. PerD appeared to selectively bind Fyn, whereas Ac-perD appeared to act as a weak but broad-spectrum inhibitor of kinases, including Fyn. In conclusion, perD and Ac-perD suppressed the phosphorylation of signal transduction molecules downstream of the Fc ε RI and consequently inhibited degranulation, and/or IL-4 production. These may be beneficial potential lead compounds for the development of novel anti-allergic and anti-inflammatory drugs., Competing Interests: This work was partially supported by a Kinjo Gakuin University Research Grant., (Thieme. All rights reserved.)- Published
- 2022
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42. Risk Factors for Perforation During Endoscopic Papillary Large Balloon Dilation and Bile Duct Stone Removal.
- Author
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Yamauchi H, Iwai T, Okuwaki K, Miyata E, Kawaguchi Y, Matsumoto T, Uehara K, Tamaki A, Araki M, Ohno T, Imaizumi H, Kida M, and Koizumi W
- Subjects
- Aged, Cholangiopancreatography, Endoscopic Retrograde adverse effects, Dilatation adverse effects, Humans, Male, Retrospective Studies, Risk Factors, Treatment Outcome, Gallstones etiology, Sphincterotomy, Endoscopic adverse effects
- Abstract
Background: Stone removal using endoscopic papillary large balloon dilation (EPLBD) is extremely effective. However, limited research exists regarding the risk factors for perforation of the duodenal papilla and bile duct, which may be fatal., Aims: We aimed to investigate the risk factors for perforation during EPLBD + stone removal., Methods: We included patients who underwent EPLBD + stone removal at four medical facilities between January 2008 and December 2018. We retrospectively analyzed the risk factors for perforation and their relationship between overdilation and adverse events. Overdilation was defined as a ratio of the balloon diameter to the diameter of the bile duct that exceeded 100%. The diameter of the distal bile duct was measured using the diameter of the intrapancreatic bile duct at a point 10 mm toward the liver from the narrow distal segment on a cholangiogram., Results: We included 310 patients (177 males; median age: 79 years [range: 46-102 years]). Perforation occurred in five patients (1.6%). Multivariate analysis indicated that no surrounding-pancreas (half or less of the circumference of the intrapancreatic bile duct was surrounded by the pancreatic parenchyma) was a significant risk factor (perforation rate: 8.3%, p = 0.011, odds ratio: 12.7 [95% confidence interval: 1.8-90.5]). No significant difference was found between the overdilation and non-overdilation groups regarding the occurrence of pancreatitis, bleeding, and cholangitis. Perforation rate in patients with no surrounding pancreas + overdilation was 16.7% (2/12). Patients with perforation underwent conservative therapy, which improved their conditions., Conclusions: EPLBD + stone removal should be avoided in patients with no surrounding pancreas. Overdilation is not a risk factor for adverse procedural events; however, it should be limited in patients with surrounding pancreas., (© 2021. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)
- Published
- 2022
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43. Differentiation of Yersinia enterocolitica enteritis from other bacterial enteritides by ultrasonography: A single-center case-control study.
- Author
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Miyata E, Jimbo K, Kyodo R, Suzuki M, Kudo T, and Shimizu T
- Subjects
- Case-Control Studies, Child, Humans, Retrospective Studies, Ultrasonography, Bacterial Infections, Enteritis diagnostic imaging, Yersinia Infections diagnostic imaging, Yersinia Infections microbiology, Yersinia enterocolitica
- Abstract
Background: The diagnosis of Yersinia enterocolitica (Ye) enteritis is not easy because detection from stool culture is more difficult for Ye than for other bacterial enteritides. The establishment of characteristic ultrasonographic findings for Ye enteritis would help improve the detection rate of Ye enteritis along with performance of several cold cultures. This would facilitate appropriate selection of antibiotics based on antimicrobial susceptibility testing and contribute to a more accurate understanding of local public health. This study aimed to retrospectively compare ultrasonographic findings and clinical features between children with Ye enteritis and other bacterial enteritides., Methods: We identified patients treated for Ye enteritis (Ye group; n = 27) or other bacterial enteritides (Other enteritis group; n = 29) between 2014 and 2018. Ultrasonographic findings (including mean maximum diameter and mean major-minor axis ratio of ileocecal lymph nodes, wall thickness of the terminal ileum, and presence of a pericecal hyperechoic region), clinical symptoms, and laboratory findings at first visit were compared between groups., Results: No difference in mean maximum diameter of ileocecal lymph nodes was seen between groups. However, mean major-minor axis ratio of ileocecal lymph nodes was lower in the Ye group than in the Other enteritis group (p < 0.001). Presence of a pericecal hyperechoic region was more frequent in the Ye group than in the Other enteritis group (p < 0.001). The combined presence of a mean ileocecal lymph node major-minor axis ratio <1.51 and a pericecal hyperechoic region offered 100% sensitivity., Conclusion: Characteristic ultrasonographic findings identified in this study may improve ultrasonographic differentiation of Y. enterocolitica enteritis from other bacterial enteritides., Competing Interests: Declaration of competing interest The authors declare that they have no conflict of interest., (Copyright © 2022 Taiwan Pediatric Association. Published by Elsevier B.V. All rights reserved.)
- Published
- 2022
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44. Expression of Oncogenic Molecules in Pediatric Ulcerative Colitis.
- Author
-
Arai N, Kudo T, Tokita K, Kyodo R, Sato M, Miyata E, Hosoi K, Ikuse T, Jimbo K, Ohtsuka Y, and Shimizu T
- Subjects
- Adult, Child, Humans, Intestinal Mucosa pathology, Colitis, Ulcerative pathology, Irritable Bowel Syndrome pathology
- Abstract
Introduction: Long-term disease duration of ulcerative colitis (UC) is known to increase the risk of developing colorectal cancer in adults; however, this association has not been genetically analyzed in children with UC. Herein, we examined the expression of cancer-related genes in the colonic mucosa of pediatric UC patients and their risk of developing colorectal cancer., Methods: Microarray analysis of cancer-related gene expression was conducted on rectal mucosa biopsy specimens randomly selected from pediatric cases, including 4 active-phase UC cases, 3 remission-phase UC cases, and 3 irritable bowel syndrome control cases. The subject pool was then expanded to 10 active-phase cases, 10 remission-phase cases, and 10 controls, which were analyzed by real-time polymerase chain reaction (PCR) and immunohistochemical staining., Results: The microarray results indicated significantly higher expression levels of cancer-related genes PIM2 and SPI1 in the active group than in the remission and control groups (p < 0.05). Real-time PCR confirmed that PIM2 and SPI1 expression levels were significantly higher, whereas TP53 and APC expression levels were significantly lower, in the active-phase group than in the remission and control groups (p < 0.05). Immunohistochemical staining for PIM2, SPI1, TP53, and APC proteins supported the real-time PCR results., Conclusions: Expression levels of previously unreported cancer-related genes in adult UC patients were significantly higher in pediatric UC patients than in controls. Inflammation of the gastrointestinal mucosa increased the expression levels of cancer-related genes even in childhood-onset UC cases, suggesting that chronic inflammation from childhood may increase the risk of colorectal cancer development., (© 2021 The Author(s) Published by S. Karger AG, Basel.)
- Published
- 2022
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45. Novel pediatric granulomatosis with polyangiitis with a marked bloody pericardial effusion and bloody stool: a case report.
- Author
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Kato M, Jimbo K, Nagata M, Endo Y, Kashiwagi K, Maruyama K, Ito N, Tokushima K, Arai N, Kyodo R, Sato M, Miyata E, Hosoi K, Inage E, Ikuse T, Fukunaga H, Kudo T, and Shimizu T
- Abstract
Background: Granulomatosis with polyangiitis (GPA) is a syndrome of refractory vasculitis involving the upper respiratory tract, lungs, kidneys, and systemic small and medium-sized arteries that affects all age groups. No pediatric case with a bloody pericardial effusion resulting in cardiac tamponade and co-existing hematochezia has been reported., Case Presentation: A 14-year-old boy was referred for evaluation of prolonged fever, chest pain, and intermittent hematochezia. Diagnostic imaging showed a prominent pericardial effusion. Immediately after admission, his systolic blood pressure decreased. Emergent pericardiocentesis resulted in aspiration of a massive amount of bloody pericardial fluid. This was diagnosed as cardiac tamponade because his blood pressure recovered immediately after the drainage. The patient had an elevated serine proteinase 3-anti-neutrophil cytoplasmic antibody (PR3-ANCA) level on serological examination. Head MRI showed thickening of nasal and sinusoidal mucosa and a cystic mass in the left sphenoid sinus. After ruling out malignancy based on the cytology of the effusion, chest MRI, and gallium scintigraphy, total colonoscopy showed multiple irregular-shaped aphthae from the right transverse colon to the cecum on the contralateral side of the mesenteric attachments. Biopsy specimens of aphthous lesions confirmed necrotizing granulomatous inflammation. A diagnosis of GPA was made based on these findings, and oral prednisolone (PSL) and azathioprine were started. The hematochezia disappeared rapidly, and no recurrence of pericardial effusion was seen after PSL tapering was completed. The PR3-ANCA level decreased into the normal range immediately after the initial therapy., Conclusions: Pericarditis is a common cardiac complication of GPA, but there have been no reports of resultant cardiac tamponade. This is the first case of pediatric GPA with cardiac and gastrointestinal complications preceding the common symptoms such as respiratory or renal symptoms. A case of pediatric GPA with hematochezia is also extremely rare. In conclusion, serial measurement of ANCA levels is important in patients with persistent fever and bloody stool, such as in inflammatory bowel disease, to make the diagnosis of a vasculitic syndrome., (© 2021. The Author(s).)
- Published
- 2021
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46. Effects of Lee Silverman Voice Treatment (LSVT LOUD) on Swallowing in Patients with Progressive Supranuclear Palsy: A Pilot Study.
- Author
-
Nozaki S, Fujiu-Kurachi M, Tanimura T, Ishizuka K, Miyata E, Sugishita S, Imai T, Nishiguchi M, Furuta M, and Yorifuji S
- Abstract
Objectives: Progressive supranuclear palsy (PSP) is an uncommon progressive neurodegenerative disease with no effective cure at present. The initial symptoms resemble those of Parkinson's disease; however, the prevalence of PSP is about one-tenth that of Parkinson's disease. In many cases, dysphagia is severe, and the development of dysphagia is an early predictor of life expectancy. The aim of the current study was to define the effects of Lee Silverman Voice Treatment (LSVT LOUD) on swallowing and voice/speech in seven patients with PSP., Methods: : Each patient underwent swallowing and voice/speech evaluations before and after 4 weeks of LSVT. Swallowing motility disorders were defined, temporal measures of swallowing were determined by videofluoroscopic evaluation, and voice measures of maximum phonation and speech intelligibility in reading and monologue were examined., Results: After LSVT, the median duration of opening of the upper esophageal sphincter (from the beginning of the posterior movement of the bolus to upper esophageal sphincter opening) on videofluoroscopy was significantly shortened from 0.42 to 0.38 s (Wilcoxon signed-rank test P=0.016). The oral transit duration was decreased in five patients, but the decrease was not significant. Voice changes after LSVT included increases in voice intensity and in sustained duration were not significant., Conclusion: In this small study, it was found that LSVT may improve swallowing functions in patients with PSP., Competing Interests: CONFLICTS OF INTEREST: The authors have no conflicts of interests directly relevant to the content of this article., (©2021 The Japanese Association of Rehabilitation Medicine.)
- Published
- 2021
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47. Eradication therapy for Helicobacter pylori infection based on the antimicrobial susceptibility test in children: A single-center study over 12 years.
- Author
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Miyata E, Kudo T, Ikuse T, Tokita K, Arai N, Oka I, Kyodo R, Sato M, Hosoi K, Jimbo K, Aoyagi Y, Ohtsuka Y, and Shimizu T
- Subjects
- Breath Tests, Child, Clarithromycin therapeutic use, Drug Therapy, Combination, Gastric Mucosa, Helicobacter pylori, Humans, Anti-Bacterial Agents therapeutic use, Drug Resistance, Bacterial, Helicobacter Infections drug therapy, Microbial Sensitivity Tests
- Abstract
Background: Helicobacter pylori (H. pylori) infection causes chronic gastritis, duodenal and to a lesser extent, gastric ulcers, and gastric cancer. Most H. pylori infections are acquired in childhood, and effective treatment of childhood infection is very important. Esophagogastroduodenoscopy (EGD) is useful for endoscopic diagnosis, mucosal tissue biopsy, and culture examination for H. pylori in children and adults. In this paper, we report results of susceptibility tests and eradication rates in H. pylori-positive children who underwent EGD over a 12-year period., Materials and Methods: The subjects were H. pylori-positive pediatric patients who had gastrointestinal symptoms and underwent EGD in the Department of Pediatrics, Juntendo University Hospital (January 2007-December 2018). Patients underwent serum IgG antibody tests, fecal antigen tests, or urea breath tests, and subsequently, culture tests by gastric mucosal biopsy during EGD. H. pylori positivity was defined as a positive result on both tests. Patients received triple therapy for 14 days using our regimen, and eradication was assessed at 2, 6, and 12 months after therapy., Results: Forty-five patients were H. pylori-positive, and the overall clarithromycin (CAM) resistance rate was 71.1 % (32/45). The CAM resistance rate for the 2013-2018 period was significantly higher than the 2007-2012 period (52.6% vs. 84.6%, P < 0.05). According to the results of the antimicrobial susceptibility test, we prescribed effective antibiotics, and this resulted in a primary eradication rate of 97.7%., Conclusions: We suggest that antimicrobial susceptibility testing can significantly improve rates of primary eradication of H. pylori infection., (© 2020 John Wiley & Sons Ltd.)
- Published
- 2021
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48. Effectiveness of Biological Agents in the Treatment of Pediatric Patients with Crohn's Disease and Anal Fistulae.
- Author
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Arai N, Kudo T, Tokita K, Kyodo R, Sato M, Miyata E, Hosoi K, Ikuse T, Jimbo K, Ohtsuka Y, and Shimizu T
- Subjects
- Biological Factors, Child, Cross-Sectional Studies, Female, Humans, Male, Quality of Life, Retrospective Studies, Treatment Outcome, Crohn Disease complications, Crohn Disease drug therapy, Rectal Fistula drug therapy, Rectal Fistula etiology, Rectal Fistula surgery
- Abstract
Introduction: Anal fistulae have a significant impact on the quality of life of patients with Crohn's disease (CD). In this cross-sectional study, we aimed to determine whether biological agents were effective in treating anal fistulae in patients with CD., Methods: Fifty-three patients diagnosed with CD were retrospectively enrolled. Their data regarding symptoms, treatments, and disease progression from January 2007 to December 2016 were reviewed from the medical records. Fifteen (28%) patients with CD were complicated by anal fistulae., Results: The male-to-female ratio was 13:2, and the mean age at onset was 11 years and 6 months. Among the 15 patients, 14 (93%) had anal fistulae as an initial symptom. Almost all patients were treated by providing elemental diet, 5-aminosalicylic acid, and steroids as induction therapy. Biological agents were used in 8 patients (53.3%), and fistula closure was confirmed in all of them. Among the 7 patients not treated with biological agents, 1 (14.3%) had a recurrent anal fistula, while another had incomplete fistula closure. Regarding surgical management, 2 patients were treated using the seton method, and no patients required a colostomy., Conclusion: Treatment with biological agents is highly effective concerning the closure of anal fistulae in patients with CD, and reducing pain may improve their quality of life., (© 2021 The Author(s) Published by S. Karger AG, Basel.)
- Published
- 2021
- Full Text
- View/download PDF
49. Early voice therapy for unilateral vocal fold paralysis improves subglottal pressure and glottal closure.
- Author
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Miyata E, Miyamoto M, Shiromoto O, Kobayashi Y, Yagi M, Kitawaki T, Kawaura T, Tomoda K, and Iwai H
- Subjects
- Aged, Esophageal Neoplasms surgery, Esophagectomy adverse effects, Female, Humans, Male, Middle Aged, Phonation, Postoperative Complications etiology, Recovery of Function, Retrospective Studies, Time Factors, Vocal Cord Paralysis diagnosis, Vocal Cord Paralysis etiology, Vocal Cord Paralysis physiopathology, Glottis physiopathology, Postoperative Complications therapy, Pressure, Vocal Cord Paralysis therapy, Voice Training
- Abstract
Purpose: In cases of unilateral vocal fold paralysis (UVFP), voice disorders caused by glottic insufficiency can lead to a considerable reduction in the patient's quality of life. Voice therapy (VT) is an effective treatment that must be started early after the onset of vocal fold paralysis. This study examined the effect of early VT for patients with UVFP occurring after esophagectomy., Materials and Methods: Patients who had residual UVFP at 1 month postoperatively after esophagectomy for esophageal cancer between November 2014 and March 2017 were evaluated. Seventeen patients were divided into the VT group (n = 6) and non-VT group (n = 11). We compared these two groups and retrospectively examined the effect of early VT. The study endpoints included aerodynamic tests, laryngeal endoscopy, laryngeal stroboscopy, and glottal closure. All of these evaluations were performed at preoperatively and at 1 and 3 months postoperatively., Results: Subglottal pressure reduced notably in the VT group, and both the mean flow rate and maximum phonation time tended to improve after VT. Conversely, there were no significant differences in MFR and MPT in the non-VT group. Furthermore, although UVFP remained after VT, we achieved glottal closure for all three patients. Conversely, only two of the six patients with glottic insufficiency in the non-VT group achieved glottal closure., Conclusion: VT may be effective for improving impaired vocal function in patients with UVFP. It is reasonable to expect that VT can be initiated 1 month after the onset of vocal fold paralysis., (Copyright © 2020 Elsevier Inc. All rights reserved.)
- Published
- 2020
- Full Text
- View/download PDF
50. A non-selective endothelin receptor antagonist bosentan modulates kinetics of bone marrow-derived cells in ameliorating pulmonary hypertension in mice.
- Author
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Kato T, Mitani Y, Masuya M, Maruyama J, Sawada H, Ohashi H, Ikeyama Y, Otsuki S, Yodoya N, Shinohara T, Miyata E, Zhang E, Katayama N, Shimpo H, Maruyama K, Komada Y, and Hirayama M
- Abstract
The aim of this study was to investigate whether a dual endothelin receptor antagonist bosentan modulates the kinetics of bone marrow-derived stem cells in inhibiting the development of pulmonary hypertension. Bone marrow chimeric mice, transplanted with enhanced green fluorescent protein (eGFP)-positive bone marrow mononuclear cells, were exposed to hypobaric hypoxia or kept in the ambient air, and were daily treated with bosentan sodium salt or saline for 21 days. After the treatment period, right ventricular pressure was measured and pulmonary vascular morphometry was conducted. Incorporation of bone marrow-derived cells was analyzed by immunohistochemistry. Gene expression and protein level in the lung tissue were evaluated by quantitative real-time PCR and western blotting, respectively. The results showed that, in hypoxic mice, right ventricular pressure and the percentage of muscularized vessel were increased and pulmonary vascular density was decreased, each of which was reversed by bosentan. Bone marrow-derived endothelial cells and macrophages in lungs were increased by hypoxia. Bosentan promoted bone marrow-derived endothelial cell incorporation but inhibited macrophage infiltration into lungs. Quantitative real-time PCR analysis revealed that interleukin 6, stromal cell-derived factor-1, and monocyte chemoattractant protein-1 were upregulated by hypoxia, in which interleukin 6 and monocyte chemoattractant protein-1 were downregulated and stromal cell-derived factor-1 was upregulated by bosentan. Protein level of endothelial nitric oxide synthase (eNOS) in the whole lung was significantly upregulated by hypoxia, which was further upregulated by bosentan. Bosentan modulated kinetics of bone marrow-derived ECs and macrophages and related gene expression in lungs in ameliorating pulmonary hypertension in mice. Altered kinetics of bone marrow-derived stem cells may be a novel mechanism of the endothelin receptor blockade in vivo and confer a new understanding of the therapeutic basis for pulmonary hypertension., (© The Author(s) 2020.)
- Published
- 2020
- Full Text
- View/download PDF
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